HK1152997B - Cartridge, and electrophotographic image forming apparatus which uses cartridge - Google Patents

Description

Cartridge and electrophotographic image forming apparatus using the same

Technical Field

The present invention relates to a cartridge, and an electrophotographic image forming apparatus to which the cartridge is detachably mounted.

Here, the electrophotographic image forming apparatus denotes an electrophotographic copying machine, an electrophotographic printer (laser printer, LED printer, etc.), and the like.

The cartridge denotes a developing cartridge as well as a process cartridge. Here, the developing cartridge denotes a cartridge having a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive member, which is detachably mountable in the main assembly of an electrophotographic image forming apparatus. Some electrophotographic image forming apparatuses are configured such that an electrophotographic photosensitive member is a part of the main assembly of the image forming apparatus, and some electrophotographic image forming apparatuses are configured to employ a process cartridge (process unit) composed of an electrophotographic photosensitive member and a developing roller. A process cartridge is a cartridge in which an electrophotographic photosensitive member and one or more process members, i.e., a charging member, a developing roller (developing member), and a cleaning means, are integrally arranged, and is detachably mountable in a main assembly of an electrophotographic image forming apparatus. More specifically, the process cartridge means a cartridge in which an electrophotographic photosensitive member and at least a developing roller (developing means) are integrally arranged so that they can be detachably mounted in the main assembly of the electrophotographic image forming apparatus; or a cartridge in which an electrophotographic photosensitive member, a developing roller (developing means), and a charging means are integrally arranged so that they can be detachably mounted in the main assembly of the electrophotographic image forming apparatus. The process cartridge also means a cartridge in which an electrophotographic photosensitive member, a developing roller (developing means), and a cleaning means are integrally arranged so that they can be detachably mounted in the main assembly of the electrophotographic image forming apparatus. Further, the process cartridge means a cartridge in which an electrophotographic photosensitive member, a developing roller (developing means), a cleaning means and a charging means are integrally arranged so that they can be detachably mounted in the main assembly of the electrophotographic image forming apparatus.

The developing cartridge or the process cartridge can be detachably mounted into the main assembly of the electrophotographic image forming apparatus by the user himself, so that the user can perform maintenance of the image forming apparatus by himself, that is, without relying on a maintenance person. Therefore, the developing cartridge or the process cartridge can significantly improve the operability of the electrophotographic image forming apparatus, particularly the maintenance operation.

Background

An electrophotographic image forming apparatus develops an electrostatic latent image formed on an electrophotographic photosensitive member, which is in the form of a drum (hereinafter referred to as a photosensitive drum), using a developing device (developing roller). Conventionally, an electrophotographic image forming apparatus is configured in the following manner.

In some conventional electrophotographic image forming apparatuses, a cartridge (developing cartridge or process cartridge) has a gear. The cartridge is mounted in the main assembly of the image forming apparatus in such a manner that the gear of the cartridge engages the gear which the main assembly has. In this way, the developing roller in the cartridge can be rotated by the rotational force transmitted to the developing roller from the motor provided in the main assembly through the gear of the main assembly and the gear of the cartridge (U.S. Pat. No.7,027,754).

In another conventional electrophotographic image forming apparatus, a cartridge has a cartridge portion of a developing cartridge coupling, and a main assembly has a main assembly portion of a developing roller coupling. Further, the main assembly has a member for moving (forwardly or rearwardly) the main assembly portion of the developing roller coupling so that the main assembly portion of the developing roller coupling is movable forwardly (toward the cartridge) in the axial direction of the coupling to engage the main assembly portion of the coupling with the cartridge portion of the coupling, or so that the main assembly portion of the developing roller coupling is movable rearwardly (away from the cartridge) in the axial direction of the coupling to disengage the main assembly portion of the coupling from the cartridge portion of the coupling.

In this way, when the main assembly portion of the developing roller coupling is rotated after the cartridge is properly mounted in the main assembly, the rotational force of the main assembly portion of the developing roller coupling is transmitted to the cartridge portion of the developing roller coupling, thereby rotating the developing roller (U.S. patent No.2007/0,160,384).

However, with the above-described conventional structural arrangement, it is necessary to move the main assembly portion of the developing roller coupling in the axial direction thereof when the cartridge is mounted to or dismounted from the main assembly of the image forming apparatus in a direction substantially perpendicular to the axis of the developing roller in the cartridge. That is, when the cartridge is mounted or dismounted, the main assembly portion of the developing roller coupling must be moved in the horizontal direction by the opening or closing movement of the cover disposed on the main assembly. That is, the opening movement of the main assembly cover must move the main assembly portion of the developing roller coupling in the direction of separation from the cartridge portion of the developing roller coupling, and the closing movement of the main assembly cover must move the main assembly portion of the developing roller coupling in the direction of engagement with the cartridge portion of the developing roller coupling.

In other words, one of the above-described conventional techniques has to configure the main assembly of the image forming apparatus such that the above-described rotating member (moving member) is moved in a direction parallel to the axis thereof by a movement of opening or closing the cartridge cover of the main assembly.

In another conventional structural arrangement, there is no need to move the cartridge driving gear of the main assembly forward or backward in a direction parallel to the axis of the driving gear when mounting or dismounting the cartridge into or from the main assembly of the image forming apparatus. Thus, this structural arrangement enables mounting or dismounting of the cartridge in a direction substantially perpendicular to the axis of the cartridge driving gear of the main assembly. However, with this structural arrangement, the portion for transmitting the driving force from the main assembly to the cartridge is the interface (meshing point) between the driving force transmitting gear of the main assembly and the driving force receiving gear of the cartridge, so that it is difficult to prevent the problem of the fluctuation in the rotational speed of the developing roller.

Disclosure of Invention

Accordingly, it is a primary object of the present invention to provide a cartridge that does not have the problems occurring in the conventional art described above, and an electrophotographic image forming apparatus compatible with the cartridge according to the present invention.

Another object of the present invention is to provide a cartridge whose developing roller can be smoothly rotated even when the cartridge is mounted in an electrophotographic image forming apparatus which does not have a mechanism for moving the main assembly portion of the coupling in a direction parallel to the axis of the coupling to transmit a rotational force to the developing roller, and further to provide an electrophotographic image forming apparatus to which the above-described cartridge can be detachably mounted.

Another object of the present invention is to provide a cartridge which is detachable from the main assembly of an electrophotographic image forming apparatus having a cartridge driving shaft in a direction substantially perpendicular to the axis of the cartridge driving shaft, and further to provide an electrophotographic image forming apparatus to which the above-described cartridge is detachably mountable.

Another object of the present invention is to provide a cartridge mountable in a main assembly of an electrophotographic image forming apparatus having a cartridge driving shaft in a direction substantially perpendicular to an axis of the cartridge driving shaft, and further to provide an electrophotographic image forming apparatus to which the above-described cartridge is detachably mountable.

Another object of the present invention is to provide a cartridge mountable to or dismountable from a main assembly of an electrophotographic image forming apparatus having a cartridge driving shaft in a direction substantially perpendicular to an axis of the cartridge driving shaft, and further to provide an electrophotographic image forming apparatus to which the above-described cartridge is detachably mountable.

Another object of the present invention is to provide a cartridge which is detachable in a direction substantially perpendicular to an axis of a cartridge driving shaft from a main assembly of an electrophotographic image forming apparatus having the cartridge driving shaft, a developing roller of which is smoothly rotatable, and an electrophotographic image forming apparatus to which the above-described cartridge is detachably mountable.

Another object of the present invention is to provide a process cartridge mountable in a main assembly of an electrophotographic image forming apparatus having a cartridge driving shaft in a direction substantially perpendicular to an axis of the cartridge driving shaft, a developing roller of which is smoothly rotatable, and an electrophotographic image forming apparatus to which the above-described cartridge is detachably mountable.

Another object of the present invention is to provide a cartridge mountable to or dismountable from a main assembly of an electrophotographic image forming apparatus having a cartridge driving shaft in a direction substantially perpendicular to an axis of the cartridge driving shaft, a developing roller of the cartridge being smoothly rotatable, and an electrophotographic image forming apparatus to which the above-described cartridge is detachably mountable.

Another object of the present invention is to provide a cartridge, the developing roller of which is more smoothly rotated than the developing roller in the cartridge, which receives a rotational force from the main assembly of the electrophotographic image forming apparatus by the engagement of the gear thereof with the gear of the main assembly, and an electrophotographic image forming apparatus to which the above-described cartridge can be detachably mounted.

It is another object of the present invention to provide a developing cartridge (developing device of a process cartridge) which reliably transmits a rotational force to a developing roller which has been accurately positioned with respect to a photosensitive drum and enables the developing roller to rotate smoothly, and an electrophotographic image forming apparatus to which the above-described process cartridge can be detachably mounted.

A so-called contact development method is known in which a developing roller is brought into contact with a photosensitive drum to develop an electrostatic latent image on the photosensitive drum.

Another object of the present invention is to provide a cartridge which enables its developing roller to be smoothly rotated even when it is moved in a direction of being separated from a photosensitive drum while being in contact with the photosensitive drum, and an electrophotographic image forming apparatus to which the cartridge can be detachably mounted.

There is known an electrophotographic image forming apparatus and a cartridge combination therefor, which is configured such that a rotational force for rotating a photosensitive drum and a rotational force for rotating a developing roller are received from an image forming apparatus main assembly, respectively.

Another object of the present invention is to provide a cartridge configured such that a coupling for transmitting a rotational force to rotate a photosensitive drum is moved forward or backward in a direction parallel to an axis thereof, and an electrophotographic image forming apparatus to which the above-described cartridge can be detachably mounted.

According to one aspect of the present invention, there is provided a cartridge for use with a main assembly of an electrophotographic image forming apparatus, the main assembly including a driving shaft having a rotational force applying portion, wherein the cartridge is detachable from the main assembly in a direction substantially perpendicular to an axial direction of the driving shaft, the cartridge comprising: i) a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive drum, the developing roller being rotatable about an axis thereof; and ii) a coupling member engageable with said rotational force applying portion to receive a rotational force for rotating said developing roller, said coupling member being capable of assuming a rotational force transmitting angular position for transmitting the rotational force for rotating said developing roller to said developing roller and a disengaging angular position in which said coupling member is inclined away from said rotational force transmitting angular position, wherein said coupling member is moved from said rotational force transmitting angular position to said disengaging angular position when said cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus in a direction substantially perpendicular to an axis of said developing roller.

According to another aspect of the present invention, there is provided an electrophotographic image forming apparatus to which a cartridge can be detachably mounted, the apparatus comprising: i) a drive shaft having a rotational force applying portion; and ii) a cartridge comprising: a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive drum, the developing roller being rotatable about an axis thereof; and a coupling member engageable with said rotational force applying portion to receive a rotational force for rotating said developing roller, said coupling member being capable of assuming a rotational force transmitting angular position for transmitting the rotational force for rotating said developing roller to said developing roller and a disengaging angular position in which said coupling member is inclined away from said rotational force transmitting angular position, wherein said coupling member is moved from said rotational force transmitting angular position to said disengaging angular position when said cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus in a direction substantially perpendicular to an axis of said developing roller.

The present invention can provide a cartridge which is detachable from a main assembly of an electrophotographic image forming apparatus having a cartridge driving shaft in a direction substantially perpendicular to an axis of the cartridge driving shaft, and further provide an electrophotographic image forming apparatus to which the above-described cartridge is detachably mountable.

The present invention can provide a cartridge mountable in a main assembly of an electrophotographic image forming apparatus having a cartridge driving shaft in a direction substantially perpendicular to an axis of the cartridge driving shaft, and further, an electrophotographic image forming apparatus to which the above-described cartridge is detachably mountable.

The present invention can provide a cartridge mountable to or dismountable from a main assembly of an electrophotographic image forming apparatus having a cartridge driving shaft in a direction substantially perpendicular to an axis of the cartridge driving shaft, and further provide an electrophotographic image forming apparatus to which the above-described cartridge is detachably mountable.

The present invention can provide a cartridge to be mounted into a main assembly of an electrophotographic image forming apparatus which is free from a mechanism for moving a coupling in an axial direction of the coupling to transmit a rotational force to a developing roller in the cartridge, but can still rotate its developing roller smoothly.

The present invention can provide a cartridge capable of smoothly rotating its developing roller even if it is structured such that the direction in which the cartridge is moved to be detached from the main assembly of the electrophotographic image forming apparatus is substantially perpendicular to the axis of the driving shaft provided to the main assembly.

The present invention can provide a cartridge which can smoothly rotate its developing roller even if it is configured such that the direction of moving the cartridge to mount the cartridge to the main assembly of the electrophotographic image forming apparatus is substantially perpendicular to the axis of the driving shaft provided to the main assembly.

The present invention can provide a cartridge capable of smoothly rotating its developing roller even if it is configured such that the direction in which the cartridge is moved to be mounted to or dismounted from the main assembly of the electrophotographic image forming apparatus is substantially perpendicular to the axis of the driving shaft provided to the main assembly.

The present invention can provide an electrophotographic image forming apparatus and a cartridge therefor which can rotate its developing roller more smoothly than the electrophotographic image forming apparatus and cartridge combination, which uses a set of gears to transmit a rotational force from the image forming apparatus main assembly to the cartridge.

The present invention can provide a combination of an electrophotographic image forming apparatus and a cartridge therefor, which can reliably transmit a rotational force to a developing roller in the cartridge and smoothly rotate it, even if the combination is configured such that the developing roller is positioned relative to a photosensitive drum provided to a main assembly.

The present invention can provide a combination of an electrophotographic image forming apparatus and a cartridge therefor, which can smoothly rotate a developing roller in the cartridge even if the developing roller in contact with a photosensitive drum is moved to be separated from the photosensitive drum.

The present invention can provide an electrophotographic image forming apparatus and a cartridge therefor, the mechanism for receiving a rotational force of a photosensitive drum being configured such that a coupling of the mechanism is movable in an axial direction of the coupling.

These and other objects, features and advantages of the present invention will become more apparent from the following description of the preferred embodiments of the present invention, which is to be taken in conjunction with the accompanying drawings.

Drawings

Fig. 1 is a side sectional view of a cartridge according to an embodiment of the present invention.

Fig. 2 is a perspective view of a cartridge according to an embodiment of the present invention.

Fig. 3 is a perspective view of a cartridge according to an embodiment of the present invention.

Fig. 4 is a side sectional view of the main assembly according to the embodiment of the present invention.

Fig. 5 is a perspective view of a developing roller according to an embodiment of the present invention.

FIG. 6 is a perspective and longitudinal cross-sectional view of a coupling according to an embodiment of the present invention.

FIG. 7 is a side view and a longitudinal cross-sectional view of a drive gear according to an embodiment of the present invention.

Fig. 8 is a view illustrating an assembly process of the coupling and the driving gear according to the embodiment of the present invention.

Fig. 9 is an exploded perspective view of a cartridge according to an embodiment of the present invention.

Fig. 10 is a longitudinal sectional view after assembling the cartridge according to the embodiment of the present invention.

Fig. 11 is a perspective view showing a connected state of the developing gear and the coupling.

Fig. 12 is a perspective view showing the coupler in an inclined state.

Fig. 13 is a perspective view and a longitudinal sectional view showing a main assembly driving structure according to an embodiment of the present invention.

Fig. 14 is a perspective view showing a driving structure of the developing roller according to the embodiment of the present invention.

Fig. 15 is a perspective view of a cartridge setting portion of the main assembly according to the embodiment of the present invention.

Fig. 16 is a sectional view showing a process of mounting the cartridge to the main assembly according to the embodiment of the present invention.

Fig. 17 is a perspective view illustrating a process in which the drive shaft and the coupling are engaged with each other according to the embodiment of the present invention.

Fig. 18 is a perspective view showing a process of mounting the coupling to the drive shaft according to the embodiment of the invention.

Fig. 19 is a perspective view of the coupling disposed in the main assembly and the coupling disposed in the cartridge according to the embodiment of the present invention.

Fig. 20 is a perspective view showing a process of mounting the coupling to the drive shaft according to the embodiment of the invention.

Fig. 21 is an exploded perspective view showing a drive shaft, a drive gear, a coupling, and a developing shaft according to an embodiment of the present invention.

Fig. 22 is a perspective view illustrating a process of separating the coupling from the driving shaft according to the embodiment of the present invention.

Fig. 23 is a perspective view showing a coupling according to a modified example of the embodiment of the present invention.

Fig. 24 is a perspective view showing a coupling according to a modified example of the embodiment of the present invention.

Fig. 25 is an exploded perspective view of a drive shaft according to a modified example of the embodiment of the present invention.

Fig. 26 is a perspective view of a coupling according to a modified example of the present invention.

Fig. 27 is an exploded perspective view showing only the drive shaft, the developing shaft, and the coupling according to the embodiment of the present invention.

Fig. 28 is a side view and a longitudinal cross-sectional view of a cartridge side according to an embodiment of the present invention.

Fig. 29 is a view from the apparatus and a perspective view of a cartridge setting portion of the main assembly according to the embodiment of the present invention.

Fig. 30 is a longitudinal sectional view showing a process of taking out the cartridge according to the embodiment of the present invention to the main assembly.

Fig. 31 is a longitudinal sectional view showing a mounting process of the cartridge to the main assembly according to the embodiment of the present invention.

Fig. 32 is a perspective view and a top view of a coupling according to a second embodiment of the present invention.

Fig. 33 is a perspective view showing the mounting operation of the cartridge according to the second embodiment of the present invention.

Fig. 34 is a plan view of the cartridge according to the second embodiment of the present invention as seen from the mounting direction in a state where the cartridge is mounted.

Fig. 35 is a perspective view showing the cartridge in a state where the driving of the cartridge according to the second embodiment of the present invention is stopped.

Fig. 36 is a perspective view and a longitudinal sectional view showing the taking-out operation of the process cartridge according to the second embodiment of the present invention.

Fig. 37 is a sectional view showing a state where a door provided in the main assembly is opened according to the second embodiment of the present invention.

Fig. 38 is a perspective view showing a mounting guide portion of the driving side of the main assembly according to the embodiment of the present invention.

Fig. 39 is a side view of the drive side of the cartridge according to an embodiment of the present invention.

Fig. 40 is a perspective view of the cartridge from the driving side according to the embodiment of the present invention.

Fig. 41 is a side view showing a state in which the cartridge is inserted into the main assembly according to the embodiment of the present invention.

Fig. 42 is an exploded perspective view showing a state in which a pressing member (specific to the present embodiment) is mounted to the development supporting member according to the embodiment of the present invention.

Fig. 43 is an exploded perspective view showing the development supporting member, the coupling, and the development shaft according to the embodiment of the present invention.

Fig. 44 is a perspective view showing a driving side of the cartridge according to the embodiment of the present invention.

Fig. 45 is a longitudinal sectional view showing an engaged state between the drive shaft and the coupling according to the embodiment of the invention.

Fig. 46 is a side view showing a driving side of the cartridge according to the embodiment of the present invention.

Fig. 47 is a perspective view showing a driving side of the main assembly guide according to the embodiment of the present invention.

Fig. 48 is a side view showing the relationship between the cartridge and the main assembly guide according to the embodiment of the present invention.

Fig. 49 is a side view and a perspective view showing the relationship between the main assembly guide and the coupling according to the embodiment of the present invention.

Fig. 50 is a side view of a process of mounting the cartridge according to the embodiment of the present invention to the main assembly as viewed from the driving side.

Fig. 51 is a side cross-sectional view of a cartridge according to an embodiment of the invention.

Fig. 52 is a perspective view of a cartridge according to an embodiment of the present invention.

Fig. 53 is a longitudinal sectional view of a cartridge according to an embodiment of the present invention.

Fig. 54 is a side cross-sectional view of a cartridge according to an embodiment of the invention.

Fig. 55 is a longitudinal sectional view of a cartridge according to an embodiment of the present invention.

Fig. 56 is a perspective view of a cassette according to an embodiment of the invention.

Fig. 57 is a perspective view showing a state where the development supporting member of the cartridge according to the embodiment of the present invention is omitted.

Fig. 58 is a side cross-sectional view of a cartridge according to an embodiment of the invention.

Fig. 59 is a perspective view showing a cartridge according to an embodiment of the present invention.

Fig. 60 is a side sectional view showing the main assembly according to the embodiment of the present invention.

Fig. 61 is a perspective view of a cartridge setting portion of the main assembly according to the embodiment of the present invention.

Fig. 62 is a schematic view of a process of mounting the process cartridge according to the embodiment of the present invention to the main assembly as seen from the upper part of the apparatus.

Fig. 63 is a perspective view of a process cartridge according to an embodiment of the present invention.

Detailed Description

(example 1)

First, the present invention will be described with reference to one example of the developing cartridge according to the present invention.

It should be noted herein that the developing cartridge is one example of the process cartridge.

(1) Description of developing Cartridge

First, referring to fig. 1 to 4, a developing cartridge B (hereinafter simply referred to as cartridge) according to an embodiment of the present invention is described. Fig. 1 is a sectional view of the cartridge B. Fig. 2 and 3 are perspective views of the cartridge B. Further, fig. 4 is a sectional view of the main assembly a of the electrophotographic image forming apparatus (hereinafter, referred to simply as main assembly a).

The cartridge B is mountable to or dismountable from the main assembly a by a user.

Referring to fig. 1 to 4, the cartridge B has a developing roller 110. Referring to fig. 4, the cartridge B is mounted in the main assembly a. When the cartridge B is properly positioned in its image forming position in the main assembly a, the cartridge B is rotated by receiving a rotational force from the main assembly a by a coupling mechanism (to be described later).

The developing roller 110 supplies the developer t to a portion of the electrophotographic photosensitive drum 107 (hereinafter simply referred to as a photosensitive drum) (fig. 4) in a developing region of the apparatus main assembly a. The developing roller develops the electrostatic latent image on the outer circumferential surface of the photosensitive drum 107 with the developer t. A magnetic roller 111 (fixed magnet) is provided in the developing roller 110.

The cartridge B has a developing blade 112 in contact with the developing roller 110. This developing blade 112 regulates the amount of developer t that can be held on the outer peripheral surface of the developing roller 110. It also frictionally charges the developer t.

The developer t is stored in the developer storage portion 114 of the cartridge B, and is conveyed into the developing chamber 113a of the cartridge B by the rotation of the toner agitating members 115 and 116 of the cartridge B. When a voltage is applied to the developing roller 110, the developing roller 110 rotates. Thus, the triboelectrically charged developer t layer is formed on the outer peripheral surface of the developing roller 110 by the developing roller 110. The charged toner particles in the triboelectrically charged developer layer are transferred onto the photosensitive drum 107 in the form of the above-described electrostatic latent image; the developing roller 110 develops the electrostatic latent image.

The image developed on the photosensitive drum 107 (i.e., the image formed by the developer t) is transferred onto one sheet of recording medium 102 by the transfer roller 104. The recording medium may be any medium on which an image can be formed (on which an image formed by a developer (toner) can be transferred). For example, it may be plain paper, an OHP sheet, or the like.

The cartridge B has a developing unit 119 constituted by the developing member holding frame 113 and the developer storage frame 114. More specifically, the developing unit 119 has a developing roller 110, a developing blade 112, a developing-member frame portion, a developing chamber 113a, a developer-storage frame portion 114, and agitating members 115 and 116.

The developing roller 110 is rotatable about its axis L1.

The apparatus main assembly a has a cartridge chamber 130a into which the cartridge B is mountable by a user gripping the cartridge B by gripping a handle T thereof. When the cartridge B is mounted, a coupling 150 (rotational force transmitting member, which will be described later) of the cartridge B is connected to a drive shaft 180 (fig. 17) provided to the apparatus main assembly a, so that the developing roller 110 and the like are rotated by receiving a rotational force from the apparatus main assembly a. When the user wants to take out the cartridge B from the cartridge chamber 130a of the apparatus main assembly a, the user pulls out the cartridge B by gripping the handle T. When the cartridge B is moved in the direction of being taken out from the apparatus main assembly a, the coupling 150 of the cartridge B is separated from the drive shaft 180.

The direction in which the cartridge B moves when the cartridge B is mounted into the apparatus main assembly a (the cartridge is mounted into the cartridge chamber 130a) or when the cartridge B is dismounted from the apparatus main assembly a (the cartridge is dismounted from the cartridge chamber 130a) is substantially perpendicular to the axis L3 of the drive shaft 180. This will be described in detail later.

(2) Description of electrophotographic image forming apparatus

Next, an electrophotographic image forming apparatus using the cartridge B is described with reference to fig. 4. The image forming apparatus 100 is a laser printer in this embodiment.

The main assembly of the image forming apparatus 100 is denoted by reference letter a. Incidentally, the apparatus main assembly a is a portion remaining after the cartridge B is taken out from the image forming apparatus 100.

The apparatus main assembly a has a charging roller 108 (charging member) in parallel with the photosensitive drum 107. The charging roller 108 charges the photosensitive drum 107 with a voltage applied from the apparatus main assembly a to the charging roller 108. The charging roller is in contact with the photosensitive drum 107, and is rotated by the rotation of the photosensitive drum 107.

The drum unit 120 has a photosensitive drum 107 and a cleaning blade 117a (cleaning member). The drum unit 120 further has: a storage bin 117b for storing the removed developer; a screw 117c for conveying the removed developer to a cartridge (not shown) provided to the apparatus main assembly a to store the removed developer; and a charging roller 108. These elements are integrally arranged in the apparatus main assembly a. That is, the drum unit 120 (cartridge B) and the apparatus main assembly a are configured such that the photosensitive drum 107 is accurately positioned at a predetermined position (cartridge position) in the apparatus main assembly a when the cartridge B is mounted into the apparatus main assembly a. More specifically, the drum unit 120 has a pair of bearings (not shown) projecting outward from both longitudinal end portions of the cartridge B, one at each end, each having an axis coinciding with the axis of the photosensitive drum 107. Thus, when the cartridge B is in the above-mentioned predetermined image forming position in the apparatus main assembly a, the cartridge B is supported by the pair of bearings in a pair of grooves (not shown), one for each bearing, which are provided in the apparatus main assembly a.

The above-described removed developer is the developer removed from the photosensitive drum 107 by the cleaning blade 117 a.

The drum unit 120 may be permanently connected to the apparatus main assembly a, or detachably mounted to the apparatus main assembly a. As for the structural arrangement for positioning the drum unit 120 in the apparatus main assembly a so that the photosensitive drum 107 in the drum unit 120 is accurately positioned relative to the main assembly a for image formation, any one of known structural arrangements may be employed.

The cartridge B is mounted in the apparatus main assembly a (cartridge chamber 130 a). Then, the user closes the cartridge door 109 provided to the apparatus main assembly a. When the cartridge chamber door 109 is closed, the cartridge B is pressed toward the photosensitive drum 107 by the elasticity of a pair of springs 192 provided inside the cartridge chamber door 109. Therefore, the developing roller 110 is kept pressed against the surface of the photosensitive drum 107 in such a manner that an appropriate distance is maintained between the developing roller 110 and the photosensitive drum 107 (fig. 4). That is, the cartridge B is accurately positioned with respect to the photosensitive drum 107. Thus, the developing roller 110 is also accurately positioned with respect to the photosensitive drum 107. More specifically, a pair of bearings 107a coaxial with the drum shaft are fitted to both longitudinal end portions of the drum shaft (not shown) of the photosensitive drum 107, one at each end. Further, the pair of bearings 107a are supported by a pair of bearing positioning portions 150 provided to the apparatus main assembly a. Thus, the photosensitive drum 107 is rotatable while maintaining accurate positioning relative to the apparatus main assembly a (fig. 4 and 5).

When the user needs to mount the cartridge B into the apparatus main assembly a, or when the user needs to take out the cartridge B from the apparatus main assembly a, the user opens the door 109.

An image forming operation performed by the electrophotographic image forming apparatus is as follows. The rotating photosensitive drum 107 is uniformly charged by the charging roller 108 on its portion of the outer peripheral surface that contacts the charging roller 108. Then, a laser beam is projected to the charged portion of the outer peripheral surface of the photosensitive drum 107 through an optical member 101 having a laser diode, a polygon mirror, a lens, and a deflection mirror (all not shown), while being modulated with information about an image to be formed. As a result, an electrostatic latent image reflecting information about an image to be formed is formed on the outer peripheral surface of the photosensitive drum 107. The latent image is developed by the developing roller 110 described above.

Meanwhile, one recording medium 102 in the recording medium cassette 103a is sent out of the recording medium cassette 103a in synchronization with the development of the electrostatic latent image, and then conveyed to the image transfer position by the recording medium conveying roller pairs 103c, 103d, and 103 e. A transfer roller 104 (transfer member) is provided at the transfer position. A voltage is applied from the apparatus main assembly a to the transfer roller 104. Thus, the developer image formed on the photosensitive drum 107 is transferred onto the sheet of recording medium 102.

The apparatus main assembly a has a cleaning blade 117a extending from one longitudinal end portion to the other longitudinal end portion of the photosensitive drum 107, and its cleaning edge is in elastic contact with the outer peripheral surface of the photosensitive drum 107. The cleaning blade 117a is used to remove the developer t remaining on the peripheral surface of the photosensitive drum 107 after the developer image is transferred onto the recording medium 102. After the developer t is removed from the peripheral surface of the photosensitive drum 107 with the cleaning blade 117a, the developer t is temporarily stored in the developer hopper 117 b. Then, the removed developer t in the developer hopper 117b is conveyed to the above-described magazine (not shown) for storing the removed developer by the developer conveying screw 117c in the developer hopper 117b, and then accumulated in the magazine.

After the developer image is transferred onto the recording medium 102, the recording medium 102 is conveyed to the fixing member 105 by the guide member 103 f. The fixing member 105 has a driving roller 105c and a fixing roller 105 including a heater 105 a. The fixing member 105 fixes the developer image onto the recording medium 102 by applying heat and pressure to the recording medium 102 while the recording medium 102 is conveyed past the fixing member 105. After an image is formed on the recording medium 102 (after a developer image is fixed on the recording medium 102), the recording medium 102 is further conveyed by a pair of rollers 103g and a pair of rollers 103h, and then discharged into a tray 106. The roller pairs 103c, 103d, and 103e, the guide member 103f, and the roller pairs 103g and 103h, and the like constitute the recording medium conveying member 103.

The cartridge chamber 130a is a chamber (space) in which the cartridge B is disposed. When the cartridge B is mounted in the chamber, a coupling 150 (to be described later) of the cartridge B is connected to a drive shaft 180 provided to the apparatus main assembly a. In this embodiment, the placement of the cartridge B in the cartridge chamber 130a means that the cartridge B is mounted to the apparatus main assembly a. Further, taking out the cartridge B from the cartridge chamber 130a means that the cartridge B is detached from the apparatus main assembly a.

(3) Structure of developing roller

Next, the structure of the developing roller 110 is described with reference to fig. 5. Fig. 5(a) is a perspective view of the developing roller 110 from the rotational force receiving side (hereinafter may be referred to as the driving force receiving side). Fig. 5(b) is a perspective view of the developing roller 110 as viewed from the side opposite to the driving force receiving side (hereinafter simply referred to as the opposite side).

The developing roller 110 is constituted by a developing roller cylinder 110a, a developing roller flange 151 (at a driving force receiving end), a developing roller flange 152 (at an opposite end), and a magnet roller 111.

The developing roller cylinder 110a is constituted by a cylinder made of an elastic conductive cylinder such as an aluminum cylinder and a coating layer. The outer circumferential surface of the barrel 110a carries developer. The developer carried on the cartridge 110a is charged. The longitudinal ends of the barrel 110a have openings 110a1 and 110a2, respectively, having a diameter substantially the same as the diameter of the barrel 110a, and may be fitted with the flanges 151 and 152, respectively, as described above.

The flange 151 is made of a metal material such as aluminum, stainless steel, or the like. However, it may be made of a resin material as long as it can withstand the amount of torque required to rotate the developing roller 110.

The flange 151 has a gear fitting portion 151c on which a developing roller gear 153 (fig. 8b) for driving the developer stirring members 115 and 116 (fig. 1) and the like is fitted. The flange 151 also has a bearing fitting portion 151d on which the developing roller bearing 138 is fitted to rotatably support the developing roller 110. The gear mounting portion 151c and the bearing mounting portion 151d are coaxial with the flange 151. The flange 151 also has an inner cavity for supporting the magnet roller 111, which will be described later. The flange 151 is fitted with a developing roller gear 153, and the developing roller gear 153 is fitted with a coupling 150 (to be described later) so that the coupling 150 can be inclined with respect to the axis of the developing roller 110 even when moving.

Like flange 151, flange 152 is made of a metallic material, such as aluminum or stainless steel. The flange 151 may also be made of a resin material as long as it can withstand the amount of load to which the developing roller 110 is subjected. Further, the axis of the cylinder fitting portion 152b substantially coincides with the axis of the bearing 152 a. Further, one longitudinal end of the magnet roller 111 extends beyond the corresponding longitudinal end of the developing roller 110, and is supported by a bearing 152 a.

The magnetic roller 111 is made of a magnetic material, or a resin material mixed with magnetic particles. The magnet roller 111 has two to six magnetic poles distributed in its circumferential direction. By holding the developer on the outer circumferential surface of the developing roller 110, conveyance of the developer is facilitated.

The above-described magnet roller 111 is in the developing roller tube 110a, and the fitting portion 151a of the flange 151 is fitted in the opening 110a1 of the developing roller tube 110 a. Further, the fitting portion 152b of the flange 152 is fitted in the opening 110a2 at the other longitudinal end of the developing roller cylinder 110 a. Methods of firmly attaching the flanges 151 and 152 to the developing roller cylinder 110a include adhesion, crimping, and the like. Further, a spacer 136, a developing roller bearing 138, and a developing roller gear (not shown) are assembled from the driving force receiving side of the developing roller 110. Further, the spacer 137 and the developing roller contact 156 are fitted from the opposite side of the developing roller 110.

The spacers 136 and 137 are members for regulating the gap between the developing roller 110 and the photosensitive drum 107. There is a cylindrical member made of a resin material, the thickness of which is about 200-. A spacer 136 is fitted on one longitudinal end of the developing roller cylinder 110a, and a spacer 137 is fitted on the other longitudinal end of the developing roller cylinder 110 a. The gap between the developing roller 110 and the photosensitive drum 107 is maintained at about 200-.

The bearing 138 is a bearing for rotatably supporting the developing roller 110 by the developing unit frame 113 (fig. 1).

The developing voltage contact 156 is made of a conductive material (mainly a metal material), and is formed in a coil shape. The inner surface or flange 152 of conductive developer roller cylinder 110a has a developer voltage contact 156 b. In this embodiment, the image forming apparatus is configured such that the developing voltage contact 156 contacts the flange 152. In this way, when the cartridge B is mounted in the apparatus main assembly a, an electrical connection is formed between the apparatus main assembly a and the cartridge B through an external electrical contact (not shown) of the cartridge B and the electrical contact 156a of the apparatus main assembly a. That is, when the cartridge B is in the image forming position in the apparatus main assembly a, an electrical contact (not shown) provided to the apparatus main assembly a is held in contact with an external electrical contact of the cartridge B, thereby enabling the cartridge B to receive a voltage from the apparatus main assembly a. The voltage received by the external electrical contacts of the cartridge B is supplied to the developing roller 110 through the electrical contacts 156.

(5) Rotational force transmitting part (coupling member)

Then, referring to fig. 6, an example of a coupling member as the rotational force transmitting portion is described. Fig. 6(a) is a perspective view of the coupling member as viewed from the main assembly side, and fig. 6(b) is a perspective view of the coupling member as viewed from the developing roller side. Fig. 6(c) is a view from a direction perpendicular to the coupler axis L2. Fig. 6(d) is a side view of the coupling member as viewed from the main assembly side, and fig. 6(e) is a view as viewed from the developing roller side. Fig. 6(f) is a sectional view taken along the line S3 in fig. 6 (d).

In a state where the cartridge B is placed in the setting portion 130a, the coupling member (coupling) 150 engages the drive shaft 180 of the main assembly a (fig. 17). By taking out the cartridge B from the main assembly a, the coupling 150 is separated from the drive shaft 180. In this case, the cartridge B is moved from the setting portion in the main assembly a in a direction substantially perpendicular to the direction of the axis L3 of the drive shaft 180. At the time of mounting, the cartridge B is moved to the setting portion of the main assembly a in a direction substantially perpendicular to the direction of the axis L3 of the drive shaft 180. In the state of engagement with the drive shaft 180, the coupling 150 receives a rotational force from a motor 186 (fig. 14) provided in the main assembly a through the drive shaft 180. Further, the coupling 150 transmits the rotational force to the developing roller 110. Thus, the developing roller 110 is rotated. Here, the material of the coupling 150 is a resin material composed of polyacetal, polycarbonate, PPS, or the like. However, in order to increase the rigidity of the coupling 150, glass fiber, carbon fiber, or the like may be mixed in the resin material according to the required load torque. When such materials are mixed, the rigidity of the coupling 150 is improved. Further, in the resin material, the rigidity can be further improved by inserting a metal member. Further, the entire coupling 150 may be made of metal or the like. Furthermore, the material of the coupling is also similar in the embodiments to be described below. The coupling 150 has three main parts (fig. 6 (c)).

The first part is a driven part 150a having a rotational force receiving surface (rotational force receiving part) 150e (150e1 to 150e4) for receiving a rotational force from the pin 182 by engaging with the drive shaft 180. The second portion is a driving portion 150b for transmitting the rotational force by engaging with the developing gear 153. Further, the third portion is an intermediate portion 150c interposed between the driven portion 150a and the driving portion 150 b. For example, the developing gear 153 transmits the rotational force received by the coupling 150 from the main assembly a to a developer supply roller (to be described later).

As shown in fig. 6(f), the driven portion 150a has a drive shaft insertion opening 150m, and the drive shaft insertion opening 150m is an enlarged portion that is conically enlarged away from the axis L2. As shown, the opening 150m constitutes a recess 150 z. The recess 150z is coaxial with the rotational axis L2 of the coupling 150.

The driving portion 150b has a spherical driving shaft receiving surface 150 i. By this receiving surface 150i, the coupling 150 is able to pivot (move) substantially relative to the axis L1 between the rotational force transmitting angular position and the pre-engagement angular position (or the disengaging angular position). In this way, the coupling 150 can engage the drive shaft 180 without being hindered by the free end portion 180b of the drive shaft 180 regardless of the rotational phase of the developing roller 110. As shown, the driving part 150b has a protruding structure.

Further, a plurality of drive receiving projections 150d1-d4 are provided on the circumference of the end face of the driven portion 150a (fig. 6(d), virtual circle c 1). Further, the drive receiving standby portions 150k1, 150k2, 150k3, 150k4 are provided between the adjacent projections 150d1 or 150d2 or 150d3, 150d 4. The interval of the adjacent protrusions 150d1-d4 is larger than the outer diameter of the pin 182 so that the pin (rotational force applying portion) 182 can enter the interval. These spaced gap portions are the standby portions 150k1-k 4. Further, in fig. 6(d), the clockwise downstream side of the projection 150d is provided with a rotational force receiving surface (rotational force receiving portion) 150e (150e1-e4) intersecting the rotational direction of the coupling 150. As the drive shaft 180 rotates, the pin 182 abuts one of the receiving surfaces 150e1-e 4. Further, the receiving surfaces 150e1-e4 are pushed by the outer periphery of the pin 182, thereby rotating the coupler 150 about the axis L2.

The driving part 150b has a spherical surface. For this reason, in the cartridge B, the coupling 150 can be pivoted (moved) substantially between the rotational force transmitting angular position and the pre-engagement angular position (or the separation angular position) regardless of the rotational phase of the developing roller 110. In the illustrated example, the driving portion 150b is constituted by a spherical developing shaft receiving surface 150i, and the developing shaft receiving surface 150i has the same axis L2 as the driving portion 150 b. Further, at a position passing through the center of the developing shaft receiving surface 150i, a fixing hole 150g through which a pin (rotational force transmitting portion) 155 passes is provided.

As described above, the coupling 150 has the recess 150z coaxial with the rotation axis L2 of the coupling 150. In the state where the coupling 150 is in the rotational force transmitting angular position, the recess 150z covers the free end of the drive shaft 180. Further, the rotational force receiving surfaces 150e (150e1 to 150e4) engage the free end portions of the rotational force transmitting pins (rotational force applying portions) 182 in the rotational direction of the coupling 150, the rotational force transmitting pins 182 projecting in the direction substantially perpendicular to the axis L3 of the drive shaft 180. The rotational force receiving surface 150e is a rotational force receiving portion. The pin 182 is a rotational force applying portion. In this way, the coupling 150 receives the rotational force from the driving shaft 180 to rotate. When the cartridge B is dismounted from the main assembly a, the cartridge B is moved so that the coupling 150 of the cartridge is moved in a direction substantially perpendicular to the axis L1 of the developing roller 110. In response to the movement of the cartridge B, the coupling 150 pivots (moves) from the rotational force transmitting angular position to the disengaging angular position, so that a part of the recess 150z (the free end position 150a1) sweeps the drive shaft 180. In this way, the coupling 150 can be separated from the drive shaft 180.

The rotational force receiving surface (rotational force receiving portion) 150e (150e1 to 150e4) is positioned on a virtual circle having a center S in the middle of the rotational force receiving surface 150e, the center S being on the rotational axis L2 of the coupling 150c1 (fig. 6 (d)). In this embodiment, the rotational force receiving surfaces 150e are provided at four positions.

Here, a uniform force is applied to the coupling 150 by the rotational force receiving surfaces 150e arranged oppositely. Therefore, the rotational accuracy of the coupling 150 can be improved.

In the state of being at the rotational force transmitting angular position, the axis L2 of the coupling 150 is substantially coaxial with the axis L1 of the developing roller 110. In the state where the coupling 150 is in the disengaging angular position, the coupling is inclined with respect to the axis L1 so that the upstream side (the free end portion 150A3) can sweep the free end of the drive shaft 180 from the main assembly a in the dismounting direction X6 of dismounting the cartridge B.

(6) Development gear

Referring to fig. 7, an example of the developing gear 153 supporting the coupling 150 is described. Fig. 7(a) is a view from the drive shaft side, and fig. 7(b) is a sectional view taken along the line S4-S4 in fig. 7 (a).

The opening 153g1 or 153g2 shown in fig. 7(a) is a groove extending in the rotational axis direction of the developing gear 153. A space 153f is provided between the openings 153g1 and 153g 2. When the coupling 150 is mounted to the developing gear 153, the pins 155 are received in the openings 153g1, 153g 2. Further, the developing shaft receiving surface 150i is accommodated in the space portion 153 f.

With the above-described structure, in the cartridge B, the coupling 150 can pivot (move) between the rotational force transmitting angular position and the pre-engagement angular position (or the disengaging angular position) regardless of the rotational phase of the developing roller 110 (the stop position of the pin 155).

In fig. 7(a), the clockwise upstream side of the openings 153g1, 153g2 is provided with rotational force transmitting surfaces (rotational force transmitted portions) 153h1, 153h 2. The side surface of the rotational force transmitting pin (rotational force transmitting portion) 155 of the coupling 150 contacts the transmitting surface 153h1 or 153h 2. Thus, the rotational force is transmitted from the coupling 150 to the developing roller 110. Here, the transfer surfaces 153h1-153h2 are surfaces facing the rotational direction of the developing gear 153. Thus, the transfer surfaces 153h1-153h2 are pushed by the sides of the pin 15155. In a state where the axis L1 and the axis L2 are substantially coaxial with each other, the coupling 150 rotates about the axis L2.

Here, the developing gear 153 has the transmitted portion 153h1 or 153h2, so they can be used as the rotational force transmitted member.

Similarly to the protrusion 15150d, it is desirable to provide the rotational force transmitting surfaces 15150h1, 15150h2 in a diametrically opposed manner on the circumference.

(7) Assembly of a coupling

Fig. 8 is a sectional view showing a process of assembling the coupling 150 into the developing gear 153.

Fig. 8(a) is a view showing a state where the drive transmission pin and the holding member 156 are assembled to the two-part coupling 150. Fig. 8(b) is a view of a process of assembling the thus assembled structure to the developing gear.

The holding member 156 is locked with the developing gear 153. In this way, the coupling 150 is mounted so as to be pivotable (movable) between the rotational force transmitting angular position and the pre-engagement angular position (or the disengagement angular position). Further, the movement of the coupling 150 in the direction of the axis L2 is restricted. To this end, the diameter D15 of the opening 156j is smaller than the diameter of the shaft receiving surface 150 i. More specifically, the movement of the coupling 150 is regulated by the developing gear 153 and the holding member 156. Thus, the coupling 150 is not separated from the developing roller (cartridge).

As shown in fig. 8, the driving portion 150b of the coupling 150 engages with the recess portion (space portion 153f) of the developing gear 153.

A specific mounting method of the coupler will be described below.

As shown in fig. 8(a), the driven portion 150a and the intermediate portion 150c are inserted in the direction X33 relative to a positioning member 150q having a shaft receiving surface 150i (driving portion 150 c). At this time, the holding member 156 is provided between the driven portion 150c and the positioning member 150q in advance. In this state, the pin 155 passes through the fixing hole 150g of the positioning member 150q and the fixing hole 150r of the intermediate portion 150 c. Thus, the positioning member 150q is fixed to the intermediate portion 150 c.

As shown in fig. 8(b), the coupling 150 is then moved in the direction X33. Thus, the coupling 150 is inserted into the developing gear 153. Then, the holding member 156 is inserted in the direction of arrow X33. Thus, the holding member 156 is fixed to the developing gear 153. Using this mounting method, the coupling 150 can be mounted such that there is a clearance (gap) between the positioning member 150q and the developing gear 153. In this way, the coupling 150 may change its orientation (tilt and/or shift relative to the axis L2).

The mounting method of the coupler is not limited to these mounting methods. For example, it is required that the coupling cannot move in the axial direction with respect to the developing gear 153 and can be inclined with respect to the axis of the developing gear 153 (developing roller 110).

In view of this, the coupling is formed integrally, for example. And, a flexible locking claw is provided on the developing gear 153, with which the shaft receiving surface 150i is locked. In this way retention can be achieved. Further, even in this case, a holding member may be used.

(8) Assembly of cartridge (developing cartridge)

Referring to fig. 9 and 10, the mounting of the cartridge is described. Fig. 9 is an exploded perspective view showing a driving side of the cartridge. Fig. 10(a) is a sectional view taken along line S4-S4 in fig. 2, in which axis L2 is coaxial with axis L1. Fig. 10(b) is a sectional view taken along line S5-S5 in fig. 2.

The developing gear 153 having the coupling 150 is fixed on one end portion (developing roller flange 151) of the developing roller 110 so that the driving portion 150a is exposed.

The driving side of the overall structure (developing roller 110, developing gear 153, coupling 150) is supported by the supporting member 157, and the non-driving side is supported by the developing supporting pin (not shown). Further, in this state, the entire structure is rotatably supported on the developing member frame 119. As such, they are integrally incorporated into the cartridge B (fig. 2 and 3).

In this state, the rotational force received from the drive shaft 180 is transmitted to the developing roller 110 through the coupling 150 and the developing gear 153.

Further, in this state, the axis L2 of the coupling 150 may be in a state of being substantially coaxial with the axis L1 of the developing roller 110 (fig. 10(a)), or in a state of being inclined with respect to the axis L1 (fig. 10 (b)).

Here, as shown in fig. 11, the coupling 150 is mounted to the developing member frame 119 such that the axis L2 can be inclined in any direction with respect to the axis L1. Fig. 11(a1) - (a5) are views seen in the direction of the drive shaft 180, and fig. 11(b1) - (b5) show perspective views of the elements. Here, fig. 11(b1) - (b5) show substantially the entire coupling 150 with the development gear 153 partially exploded.

In fig. 11(a1) and (b1), axis L2 is coaxial with respect to axis L1. Fig. 11(a2) and (b2) show a case where the coupling 150 is inclined upward from the above state. As shown in this figure, when the coupling 150 is tilted toward the opening 153g, the pin 155 moves along the opening 153 g. Therefore, the coupling 150 is inclined about the axis AX perpendicular to the opening 153 g.

In fig. 11(a3) and (b3), the coupling 150 is tilted to the right. As shown in this figure, when the coupling 150 is tilted in a direction perpendicular to the opening 153g, the pin 155 rotates in the opening 153 g. The pin 155 rotates about its central axis AY.

In fig. 11(a4) and (b4) and fig. 11(a5) and (b5), the case where the coupling 150 is inclined downward and to the left is shown. For the sake of brevity, the description of the rotation axes AX, AY is omitted.

In a direction different from the described tilting direction, for example, in a 45-degree direction of the direction shown in fig. 11(a1), the rotation in the direction of the rotation axis AX and the rotation in the direction of the rotation axis AY are combined, and thus such tilting (movement) is possible.

In this way, according to this embodiment, the axis L2 can be inclined in all directions with respect to the axis L1.

In this embodiment, the opening 151g extends in a direction intersecting the protruding direction of the pin 155.

Further, as shown in the figure, there is a gap between the developing gear (rotational force transmitted member) 153 and the coupling 150. As described above, the coupling 150 can be tilted (moved) in all directions.

More specifically, the transmitting surface (rotational force transmitted portion) 153h (153h1, 153h2) is movable relative to the pin 155 (rotational force transmitting portion). The pin 155 is movable relative to the transfer surface 153 h. In the rotational direction of the coupling, the transmission surface 153h and the pin 155 engage with each other. For this reason, there is a gap between the pin 155 and the transmission surface 153 h. As such, the coupler 150 may pivot in substantially all directions relative to the axis L1. In this way, the coupling 150 is mounted to the end of the developing roller 110.

It has been described that axis L2 can be tilted in all directions relative to axis L1. However, the coupling 150 does not have to be linearly inclined by a predetermined angle in any direction by 360 degrees. In this case, for example, the opening 150g is provided wider in the circumferential direction. If arranged in this manner, when axis L2 is inclined with respect to axis L1, coupling 150 can rotate by a small angle with respect to axis L2 even in the case where axis L2 cannot be linearly inclined by a predetermined angle. Thus, it can be tilted at a predetermined angle. In other words, the amount of clearance in the rotational direction of the opening 150g can be appropriately selected as needed.

This applies to all embodiments described in this specification.

In this manner, the coupler 150 is mounted to pivot in substantially any direction. For this reason, the coupling 150 is rotatable (movable) over substantially the entire circumference with respect to the developing gear 153 (the axis L1 of the developing roller 110). As described above (fig. 10), the spherical surface 150i of the coupling 150 contacts the holding portion (a part of the recess) 156 i. To this end, the coupling 150 is mounted concentrically with the center P2 of the spherical surface 150i (fig. 10). More specifically, the axis L2 of the coupling 150 can be inclined regardless of the phase of the developing gear 153 (developing roller 110).

In order to engage the coupling 150 with the drive shaft 180, immediately before the engagement, the axis L2 is inclined with respect to the axis L1 toward the downstream side in the cartridge B mounting direction. As shown in fig. 10(b), more specifically, the axis L2 is inclined such that the driven portion 150a is downstream of the axis L1 with respect to the mounting direction X4. In fig. 12(a) - (c), the position of the driven portion 150a is always downstream with respect to the mounting direction X4.

With the above-described structure, as shown in fig. 10, a transition from the state in which the axis L2 is substantially parallel to the axis L1 to the state in which the axis L2 is inclined can be achieved. The maximum possible inclination angle α 4 (fig. 10(b)) between the axis L1 and the axis L2 is an inclination angle at which the driven portion 15150a or the intermediate portion 15150c contacts the developing gear 153 or the bearing member 157. The inclination angle is an angle that allows the coupling 150 to engage and disengage with respect to the drive shaft 180 when the cartridge B is mounted to and dismounted from the main assembly a.

(9) Drive shaft and drive structure of main assembly

Next, referring to fig. 13 and 14, a developing roller driving structure of the main assembly a is described. Fig. 13 is a perspective view of the main assembly in a state where the cartridge B is not inserted, in which a side plate of the driving side is partially omitted. Fig. 14 is a perspective view showing only the developing roller driving structure.

The free end 180b of the drive shaft 180 is a spherical surface. It has a rotational force transmitting pin 182 as a rotational force applying portion, which passes substantially through the center of the cylindrical main body 180 a. Rotational force is transmitted by the pin 182 to the coupler 150.

Longitudinally opposite sides of the free end portion 180b have development drive gears 181 substantially coaxial with the axis L3. The gear 181 is non-rotatably fixed to the drive shaft 180. For this reason, when the gear 181 rotates, the drive shaft 180 also rotates.

The gear 181 receives a rotational force from the motor 186 through a pinion (motor pinion) 187, an idler gear 191, and a photosensitive drum drive gear 190. For this reason, when the motor 186 rotates, the driving shaft 180 also rotates.

The gear 181 is rotatably supported by the main assembly a by a supporting member (not shown). At this time, the gear 181 does not move in the direction of the axis L1. Accordingly, the gear 181 and the supporting member (not shown) may be closely arranged with respect to each other.

It has been described that the gear 181 receives the transmission of the rotational force from the gear 187 through a plurality of gears. But this is not necessarily so. For example, appropriate modifications may be made from the viewpoint of convenience in arrangement of the motor 186. The rotational force may be transmitted by a belt or the like.

Further, the drive shaft 180 does not move in the direction of the axis L3. For this reason, the clearance between the drive shaft 180 and the bearing members 183, 184 is a clearance for allowing the drive shaft 180 to rotate. Thus, the position of the gear 181 relative to the gear 187 can also be accurately determined relative to the diameter direction.

However, due to unavoidable dimensional tolerances, the drive shaft 180 may have a clearance (clearance) in the direction of the axis L3. In this case, in order to remove the clearance, a spring or the like may be used to elastically urge the drive shaft 180 or the gear 181 in the direction of the axis L3.

(10) Structure of cartridge guide portion of main assembly

Referring to fig. 15 and 16, the cartridge mounting member 130 in this embodiment has a pair of cartridge guides 130R1 and 130L1 provided to the main assembly a.

These guide portions 130R1 and 130L1 are in the space (cartridge chamber 130a) where the cartridge B is mounted. That is, the cartridge chamber 130a has the cartridge mounting member 130 whose cartridge guide portions 130R1 and 130L1 are provided in the vicinity of the end walls (left and right walls) thereof, respectively, and extend in the direction in which the cartridge B is inserted (mounted) into the cartridge chamber 130 a. The two guide portions 130R1 and 130L1 of the cartridge mounting member 130 are disposed near the left and right walls of the cartridge chamber 130a so that they are diametrically opposed to each other across the cartridge chamber 130a (fig. 15 shows the driven side of the cartridge, and fig. 16 shows the opposite side of the driven side of the cartridge). The cartridge mounting member 130 has a pair of cartridge guides 130R1 and 130L1 that guide the cartridge B when the cartridge is mounted in the cartridge chamber 130 a. As for the direction of mounting the cartridge B into the main assembly a, the guide portion 130R1 is provided at one end (right end as viewed from the direction of inserting the cartridge) of the cartridge chamber 130a, and the guide portion 130L1 is provided at the other end. The guides are positioned such that they oppose each other across the cartridge chamber 130 a. When the user mounts the cartridge B into the cartridge chamber 130a, the user inserts the cartridge B so that a pair of portions (projections, which will be described later) projecting from the longitudinal ends outside the cartridge frame are guided by the guides 130R1 and 130L 1. The step of mounting the cartridge B into the apparatus main assembly a is as follows. First, the user opens the door 109, and the door 109 can be opened or closed around the axis 109 a. Next, the user inserts the cartridge B into the cartridge chamber 130a while the above-described convex portions are guided by the guide portions 130R1 and 130L 1. Next, the user closes the door 109. Closing the door 109 completes the mounting of the cartridge B into the apparatus main assembly a. Incidentally, the door 109 is also opened when the user takes out the cartridge B from the apparatus main assembly a.

The slot 130R2 is on the cartridge drive side of the cartridge compartment 130a and serves as clearance for the coupling 150 until the coupling 150 engages the drive shaft 180.

The door 109 has a spring 192 on the inside of the door 109. When the door 109 is in the closed position, the spring 192 elastically presses the cartridge B, thereby maintaining a predetermined amount of distance between the developing roller 110 and the photosensitive drum 107. That is, the spring 192 elastically presses the cartridge B, thereby pressing the developing roller 110 toward the photosensitive drum 107.

(11) Structural arrangement for guiding and positioning developing cartridge

Referring to fig. 2 and 3, cartridge B has a pair of cartridge guides 140R1, 140R2, and a pair of cartridge guides 140L1, 140L 2. In terms of the axial (longitudinal) direction of the developing roller 110, the cartridge guides 140R1, 140R2 are at one longitudinal end of the cartridge B, and the cartridge guides 140L1, 140L2 are at the other longitudinal end.

In this embodiment, the guides 140R1, 140R2, 140L1, and 140L2 are integral parts of the developing unit frame 119, the developing roller supporting member 157, or the developing roller bearing 139, and are integrally molded therewith. They may protrude outside the cartridge B.

(12) Mounting operation of developing cartridge

Next, with reference to fig. 17, an operation for mounting the cartridge B into the apparatus main assembly a is described. Fig. 17(a) -17(c) are sectional views of the cartridge B and the cartridge chamber portion of the apparatus main assembly a, taken on the plane S6-S6 in fig. 15.

Referring to fig. 17(a), the user opens the door 109 of the apparatus main assembly a, and mounts the cartridge B into the cartridge mounting member 130 (cartridge chamber 130 a).

More specifically, referring to fig. 17(B), the cartridge B is mounted into the cartridge chamber 130a by inserting the cartridge B into the apparatus main assembly a so that the cartridge guides 140R1 and 140R2 on the driving force receiving side follow the cartridge guides 130R1 of the apparatus main assembly a, and so that the cartridge guides 140L1 and 140L2 on the opposite side of the driving force receiving side follow the cartridge guides 130L1 (fig. 16) of the apparatus main assembly a. When the cartridge B is inserted as described above, the coupling 150 on the driving force receiving side and the cylindrical portion 157c of the developing roller supporting member 157 (which surrounds the coupling 150) follow the groove 130R2 of the guide portion 130R1 without contact between the cylindrical portion 157c and the wall of the groove 130R 2.

Next, the cartridge B is further inserted in the direction indicated by the arrow X. When the cartridge B is inserted as described above, the coupling 150 engages the drive shaft 180, thereby allowing the cartridge B to be properly seated in the cartridge compartment 130a (a predetermined position in the cartridge compartment 130a), which will be described later in more detail. More specifically, referring to fig. 17(c), guide 140R1 contacts cartridge positioning portion 130R1a of guide 130R 1. Further, guide 140L1 contacts cartridge positioning portion 130L1a of guide 130L1 (fig. 16). As described above, the cartridge B is detachably mounted into the cartridge chamber 130a with the aid of the cartridge mounting member 130. At the end of mounting (inserting) the cartridge B into the cartridge compartment 130a, the coupling 150 engages the drive shaft 180. When the cartridge B remains properly positioned in the image forming position in the cartridge compartment 130a, the coupling 150 remains engaged with the drive shaft 180 so that the cartridge B can perform a part of the image forming operation. Incidentally, the cartridge chamber 130a is a space in the apparatus main assembly a, which is a space in which the cartridge B is located when the cartridge B is held in the apparatus main assembly a after the cartridge mounting member 130 assists the user to mount the cartridge B into the apparatus main assembly a.

As described above, the cartridge B has the pair of guide portions 140R1 and 140R2 that protrude from one longitudinal end (fig. 2) of the cartridge B. With respect to the direction X4 in which the cartridge B is mounted into the apparatus main assembly a, there is a predetermined amount of distance (gap) between the guides 140R1 and 140R 2. Further, the cartridge B has a pair of guide portions 140L1 and 140L2 that protrude from the other longitudinal end portion (fig. 3) of the cartridge B. With respect to the direction X4 in which the cartridge B is mounted into the apparatus main assembly a, there is a predetermined amount of distance (gap) between the guide portions 140L1 and 140L 2.

With the apparatus main assembly a, one end of its cartridge chamber 130a has guides 130R1 and 130R2 in a direction perpendicular to the cartridge mounting direction X4, which are aligned with each other in a direction parallel to the cartridge mounting direction X4, and the guide 130R1 is positioned higher than the guide 130R2 (fig. 15). The other end of the cartridge chamber 130a has guides 130L1 and 130L2, which are aligned with each other in a direction parallel to the cartridge mounting direction X4 (fig. 16).

In this way, when the cartridge B is mounted into the cartridge chamber 130a, the cartridge B is inserted into the cartridge chamber 130a such that the guides 140R1 and 140R2 are guided by the guide 130R1 and the bottom surface of the cartridge B is guided by the guide 130R2 (fig. 17). For the opposite sides of the guides 140R1 and 140R2, the guides 140L1 and 140L2 are guided by the guides 130L 1.

Further, after the coupling 150 engages the drive shaft 180, the guides 140R1 (fig. 17) and 140L1 (fig. 16) are accurately positioned with respect to the cartridge chamber 130a by the cartridge positioners 130R1a and 130L1a, respectively. That is, after the coupling 150 is engaged with the drive shaft 180, the cartridge B is accurately positioned in the cartridge chamber 130 a.

How the coupling 150 is engaged with the drive shaft 180 and how the coupling 150 is disengaged from the drive shaft 180 will be described later.

If it is necessary to take out the cartridge B from the cartridge chamber 130a, the cartridge B can be taken out from the cartridge chamber 130a only by performing the above-described cartridge mounting operation in reverse.

The above-described structural arrangement for the cartridge B and the apparatus main assembly a enables the cartridge B to be taken out of the cartridge chamber 130a by moving the cartridge B in a direction substantially perpendicular to the axis of the drive shaft 180. That is, the cartridge B can be mounted to or removed from the cartridge chamber 130a by moving the cartridge B in a direction substantially perpendicular to the axis of the drive shaft 180.

After the cartridge B is properly positioned at the image forming position in the cartridge chamber 130a of the apparatus main assembly a, the guide 140R1 is still under the pressure from the elasticity of the spring 188R provided to the apparatus main assembly a (fig. 2 and 15), and the guide 140L1 is still under the pressure from the elasticity of the spring 188L provided to the apparatus main assembly a (fig. 3 and 16). Then, after the door 19 is closed, the cartridge B is pressed against the cartridge holder 114a (fig. 4) due to the elasticity of the spring 192R (as for the spring 192L, i.e., the spring on the opposite side to the driving force receiving side, see fig. 16) connected to the inner surface of the door 109. In this way, the spacers 136 and 137 (fig. 2) fitted on both longitudinal end portions of the developing roller 110 in one-to-one correspondence are brought into contact with both longitudinal end portions of the photosensitive drum 107, thereby maintaining a predetermined amount of distance between the developing roller 110 and the photosensitive drum 107.

Further, the closing of the door 109 causes an opening and closing device (not shown) to be opened, thereby enabling the developing roller 110 to receive the rotational force for rotating the developing roller 110 from the apparatus main assembly a through the drive shaft 180 and the coupling 150.

As described above, the user detachably mounts the cartridge B into the cartridge chamber 130a under the guidance of the cartridge mounting member 130. That is, the cartridge B is mounted into the cartridge chamber 130a while being accurately positioned with respect to the apparatus main assembly a and the photosensitive drum 107. Further, after the cartridge B is accurately positioned in the cartridge chamber 130a, the drive shaft 180 and the coupling 150 are completely engaged.

That is, the coupling 150 is in the rotational force receiving state.

That is, the electrophotographic image forming apparatus in this embodiment can form an image by mounting the cartridge B into the cartridge chamber 130a of the image forming apparatus.

Incidentally, as to how the cartridge B is mounted, the apparatus main assembly a and the cartridge B may be structured such that the user himself can insert the cartridge B completely into the cartridge chamber 130a, or the user inserts the cartridge B partially so that the remaining portion of the mounting of the cartridge B can be completed using other means. For example, the apparatus main assembly a may be structured such that when the door 109 is closed, a part of the door 109 contacts the cartridge B which has been partially inserted, and then the cartridge B is pushed to its final position in the cartridge chamber 130a by the remaining part of the closing movement of the door 109. Alternatively, the cartridge B and the apparatus main assembly a may be structured such that the user partially pushes the cartridge B into the cartridge chamber 130a, and then the cartridge B is advanced to its final position in the cartridge chamber 130a by its own weight.

As shown in fig. 17, the cartridge B is mounted to and dismounted from the main assembly a by moving the cartridge B in a direction substantially perpendicular to the direction of the axis L3 (fig. 18) of the drive shaft 180. Further, the drive shaft 180 and the coupling 150 are in an engaged state or a disengaged state.

"substantially vertical" will be described herein.

In order to smoothly mount and dismount the cartridge B between the cartridge B and the main assembly a, a small gap is given therebetween. More specifically, there are small gaps between the longitudinal directions of guide 140R1 and guide 130R1, between the longitudinal directions of guide 140R2 and guide 130R1, between the longitudinal directions of guide 140L1 and guide 130L1, and between the longitudinal directions of guide 140L2 and guide 130L 2. Therefore, when the cartridge B is mounted to and dismounted from the main assembly a, the entire cartridge B may sometimes be slightly inclined within the limits of its gap. Therefore, strictly speaking, the mounting and the removal are sometimes not in the orthogonal direction. However, even in this case, the functional effects of the present invention can be achieved. Thus, "substantially vertical" includes the case where the cartridge is slightly tilted.

(13) Engagement operation and rotational force transmission between coupling and drive shaft

As described above, the coupling 150 of the cartridge B engages the drive shaft 180 immediately before being positioned in the mounting portion 130a (predetermined position), or engages the drive shaft 180 while being positioned in the predetermined position. More specifically, the coupling 150 is in the rotational force transmitting angular position. Here, the predetermined position is the setting portion 130 a.

Referring to fig. 18 and 19, an engaging operation between the coupling 150 and the drive shaft 180 is described. Fig. 18 is a perspective view showing the drive shaft and the main portion of the cartridge drive side. Fig. 19 is a longitudinal sectional view seen from the lower side of the main assembly. Here, the engagement refers to a state in which the axis L2 and the axis L3 are substantially coaxial with each other, in which a rotational force can be transmitted.

As shown in fig. 19, the cartridge B is mounted into the main assembly a in a direction (the direction of arrow X4) substantially perpendicular to the axis L3 of the drive shaft 180. Alternatively, it is detached from the main assembly a. The coupling 150 is in a pre-engagement angular position in which the axis L2 (fig. 19(a)) is inclined in advance toward the mounting direction X4 with respect to the axis L1 (fig. 19(a)) of the developing roller 110 (fig. 18(a) and 19 (a)).

As for the structure for tilting the coupler to the pre-engagement angular position, for example, the structure of embodiment 4 or the structure of embodiment 5, which will be described below, is used. However, the invention is not limited thereto, and other suitable configurations may be used.

By tilting the coupling 150 in the above-described direction, the free end position 150a1 of the coupling 150 downstream with respect to the mounting direction X4 is closer to the position of the developing roller 110 with respect to the direction of the axis L1 than the free end 180b3 of the drive shaft. Further, the upstream free end position 150a2 is closer to the position of the pin 182 with respect to the mounting direction X4 than the free end 180b3 of the drive shaft (fig. 19(a), (b)). Here, the free end position is a position farthest from the axis L2 at a position closest to the drive shaft in the direction of the axis L2 in the driven portion 150a shown in fig. 6(a) and (c). In other words, depending on the rotational phase of the coupling 150 (fig. 6(a) (c), 150A), it is an edge line of the driven portion 150A or an edge line of the protrusion 150d of the coupling 150.

First, the free end position 150a1 of the coupling 150 (a portion of the coupling 150) sweeps past the free end 180b3 of the drive shaft. And, after the coupling 150 sweeps over the free end 180b3 of the drive shaft, the receiving surface 150f or the projection 150d contacts the free end 180b or the pin 182 of the drive shaft 180 (fig. 19 (b)). The receiving surface 150f and the projection 150d are cartridge-side contact portions. The drive shaft 180 is a main assembly side engaging portion. The pin 182 is a main assembly side engaging portion and a rotational force applying portion. In the coupling 150, in response to the mounting operation of the cartridge B, the coupling 150 is tilted (fig. 19(c)) so that the axis L2 is coaxial with the axis L1. The coupling 150 is inclined from the pre-engagement angular position, pivoted (moved) to the rotational force transmitting angular position, at which the axis L2 of the coupling is substantially coaxial with the axis L1. Finally, the position of the cartridge B is determined relative to the main assembly a. At this time, the drive shaft 180 and the developing roller 110 are substantially coaxial with each other. Further, in this state, the receiving surface 150f is opposed to the spherical surface free end portion 180b of the drive shaft 180. And, the coupling 150 and the drive shaft 180 are engaged with each other (fig. 18(b) and 19 (d)). Further, at this time, the pin 155 (not shown) is positioned in the opening 150g (fig. 6 (b)). Further, the pin 182 is located at the standby position 150 k. Here, the coupler 150 covers the free end portion 180 b.

As described hereinabove, when the cartridge B is mounted to the main assembly a, the coupling 150 performs the following movement. More specifically, when the downstream portion (the free end position 150a1) of the coupling 150 with respect to the mounting direction X4 bypasses the drive shaft 180, the coupling 150 is inclined and moved from the pre-engagement angular position to the rotational force transmitting angular position. The receiving surface 150f constitutes a recess 150 z. The recess 150z has a conical shape. The mounting direction X4 is a direction in which the cartridge B is mounted to the main assembly a.

As described hereinabove, the coupler 150 is mounted for tilting movement relative to the axis L1. And, in response to the movement of the cartridge B, a part of the coupling 150 (the receiving surface 150f and/or the projection 150d) as a cartridge side contact portion contacts the main assembly side engaging portion (the drive shaft 180 and/or the pin 182). In this way, the pivotal movement of the coupling 150 is performed. As shown in fig. 19, the coupling 150 is mounted in a state of overlapping with the drive shaft 180 with respect to the direction of the axis L1. However, the coupling 150 may be engaged with the driving shaft 180 in an overlapped state by the pivotal movement of the coupling described above.

Further, the engagement operation of the coupling 150 described above can be performed regardless of the phase difference between the drive shaft 180 and the coupling 150. The reason for this is described with reference to fig. 11 and 20. Fig. 20 is a view showing respective phases of the coupling 150 and the drive shaft 180. Fig. 20(a) is a view showing a state in which the pin 182 and the receiving surface 150f are opposed to each other on the cartridge downstream side with respect to the mounting direction X4. Fig. 20(b) is a view showing a state in which the pin 182 and the projection 150d are opposed to each other. Fig. 20(c) is a view showing a state where the free end portion 180b and the projection 150d are opposed to each other. Fig. 20(d) is a view showing a state where the free end portion 180b and the receiving surface 150f are opposed to each other.

As shown in fig. 11, the coupling 150 may be inclined in all directions with respect to the axis L1 of the developing roller 110. More specifically, the coupling 150 is rotatable. As shown in fig. 20, for this reason, in the mounting direction X4 of the cartridge B, the coupling can be inclined regardless of the phase of the developing gear 153 (developing roller). Regardless of the phase of the drive shaft 180 and the coupling 150, the free end position 150a1 can be inclined within the set inclination angle range of the coupling 150 such that it exceeds the free end 180b3 of the drive shaft in the direction of the axis L1 on the developing roller side. Further, the inclination angle range of the coupling 150 is set such that the free end position 150a2 is positioned on the pin 182 side with respect to the free end 180b3 of the drive shaft. With this setting, in response to the mounting operation of the cartridge B, the free end position 150a1 with respect to the mounting direction X4 sweeps the free end 180B3 of the drive shaft. Also, in the case shown in fig. 20(a), the receiving surface 150f contacts the pin 182. In the case shown in fig. 20(b), the projection (engaging portion) 150d contacts the pin (rotational force applying portion) 182. In the case shown in fig. 20(c), the projection 150d contacts the free end portion 180 b. In the case shown in fig. 20(d), the receiving surface 150f contacts the free end portion 180 b. Further, by the contact force between the coupling 150 and the drive shaft 180 when the cartridge B is mounted, the coupling 150 is moved so that the axis L2 is substantially coaxial with the axis L1. More specifically, after the coupling 150 comes into contact with the drive shaft 180, the cartridge B moves until the axis L2 is substantially coaxial with the axis L1. Also, in the state where the axis L2 is substantially coaxial with the axis L1, the cartridge B is positioned in the main assembly a as described above. In this way, the coupling 150 engages the drive shaft 180. More specifically, the recess 150z covers the free end 180 b. Therefore, the coupling 150 can engage the drive shaft 180 (the pin 182) regardless of the phase of the drive shaft 180 and the coupling 150 or the developing gear 153 (developing roller).

Further, as shown in fig. 20, there is a gap between the development gear 153 and the coupling 150 to allow the inclination (movement) as described above.

In this embodiment, the case where the coupling 150 pivots in the plane of the drawing sheet of fig. 20 has been described. However, since the coupling 150 can also rotate as described above, pivoting in directions other than the in-plane direction of fig. 20 may also be included. Further, in this case, it is possible to transit from the state of fig. 20(a) to the state of fig. 20 (d). This applies to the following examples unless otherwise described.

Referring to fig. 21, the rotational force transmitting operation when the developing roller 110 rotates is described. The drive shaft 180 is rotated together with the gear 181 in the direction X8 in the drawing by the rotational force received from the drive source (motor 186). And, the pin 182(182a1, 182a2) integral with the drive shaft 180 contacts one of the rotational force receiving surfaces (rotational force receiving portions) 150e1 to 150e 4. More specifically, the pin 182a1 contacts one of the rotational force receiving surfaces 150e1 to 150e 4. Further, the pin 182a2 contacts one of the rotational force receiving surfaces 150e1 to 150e 4. Thus, the rotational force of the driving shaft 180 is transmitted to the coupling 150 to rotate it. Further, by the rotation of the coupling 150, the pin 155 (rotational force transmitting portion) of the coupling 150 contacts the developing gear 153. Thus, the rotational force of the drive shaft 180 is transmitted to the developing roller 110 through the coupling 150, the pin 155, the developing gear 153, and the developing roller flange 151. Thus, the developing roller 110 rotates.

Further, in the rotational force transmitting angular position, the free end portion 153b contacts the receiving surface 150 i. And, the free end portion (positioning portion) 180b of the drive shaft 180 contacts the receiving surface (positioned portion) 150 f. In this way, the coupling 150 is positioned relative to the drive shaft 180 in a state of being suspended on the drive shaft 180 (fig. 19 d).

Here, in this embodiment, the developing roller 110 is positioned with respect to the photosensitive drum 107 by a spacer. In contrast, the drive shaft 180 is positioned on a side plate or the like of the main assembly a. In other words, the axis L1 is positioned through the photosensitive drum relative to the axis L3. For this reason, the dimensional tolerance tends to become large. Therefore, the axis L3 and the axis L1 are easily deviated from the coaxial state. In this case, the coupling 150 can appropriately transmit the rotational force by being inclined at a slight angle. Even in this case, the coupling 150 can rotate without applying a large load to the developing gear 153 (developing roller 110) and the drive shaft 180. For this reason, the accuracy required for positioning adjustment is reduced at the time of assembly mounting of the drive shaft 180 and the developing roller 110 (developing cartridge). Therefore, the workability of the assembly is improved.

This is one of a plurality of advantageous effects according to the embodiment of the present invention, in addition to the effects described above as the effects of the present invention.

Further, as has been described with reference to fig. 14, the drive shaft 180 and the gear 181 are positioned at predetermined positions (mounting portions 130a) of the main assembly a with respect to the diametrical direction and the axial direction. Further, the cartridge B is positioned at the mounting portion 130a as described above. Also, the drive shaft 180 positioned in the mounting portion 130a and the cartridge B positioned in the mounting portion 130a are coupled to each other by the coupling 150. The coupling 150 is swingably pivoted with respect to the developing roller 110. Therefore, as described above, the coupling 150 can smoothly transmit the rotational force between the drive shaft 180 positioned at the predetermined position and the cartridge B positioned at the predetermined position. In other words, even if there is a slight deviation between the drive shaft 180 and the developing roller 110, the coupling 150 can smoothly transmit the rotational force.

This is also one of the effects of this embodiment according to the present invention.

The coupling 150 contacts the drive shaft 180. Thus, it has been described that the coupling 150 swings from the pre-engagement angular position to the rotational force transmitting angular position, but this is not necessarily so. For example, an abutting portion as a main assembly side engaging portion may be provided at a position other than the main assembly drive shaft. Also, during the mounting of the cartridge B, after the free end position 150a1 passes by the free end 180B3 of the drive shaft, a part of the coupling 150 (cartridge side contact portion) contacts the abutment portion. In this way, the coupling receives a force in the swinging direction (pivoting direction) and swings (pivots) so that the axis L2 is substantially coaxial with the axis L3. In other words, any other means may be used if the axis L1 can be substantially coaxial with the axis L3 as the mounting operation of the cartridge B progresses.

(14) Separating operation between coupling and drive shaft and operation for taking out cartridge

Referring to fig. 22, the operation of disengaging the coupling 150 from the drive shaft 180 when taking out the cartridge B from the main assembly a will be described. Fig. 22 is a sectional view seen from the lower side of the main assembly.

As shown in fig. 22, when the cartridge B is dismounted from the main assembly a, the cartridge B is dismounted in a direction (the direction of arrow X6) substantially perpendicular to the direction of the axis L3.

In a state where the developing gear 153 (developing roller 110) is not rotated, the axis L2 of the coupling 150 is substantially coaxial with the axis L1 at the rotational force transmitting angular position (fig. 22 (a)). Also, when the user takes out the cartridge B from the mounting portion 130a, the developing gear 153 moves together with the cartridge B in the taking-out direction X6. And, the receiving surface 150f or the projection 150d on the upstream side of the coupling 150 with respect to the take-out direction X6 contacts at least the free end portion 180b of the drive shaft 180 (fig. 22 (a)). Then, the axis L2 of the coupling 150 starts to incline toward the upstream side in the removal direction X6 (fig. 22 b). The direction in which the coupling 150 starts to incline is the same as the direction in which the coupling 150 inclines (pre-engagement angular position) when the cartridge B is mounted. By the operation of taking out the cartridge B from the main assembly a, the coupling 150 is moved while the free end portion 150A3 on the upstream side with respect to the taking-out direction X6 contacts the free end portion 180B. In more detail, the following movement of the coupling 150 is made in response to the movement of the cartridge B in the taking-out direction X6. More specifically, when a portion of the coupling 150 (the receiving surface 150f and/or the projection 150d) as the cartridge side contact portion contacts the main assembly side engaging portion (the drive shaft 180 and/or the pin 182), the coupling 150 is moved. Also, in the separation angle position, the axis L2 is inclined until the free end 150A3 contacts the free end 180b3 (fig. 22 (c)). Also, in this state, the coupling 150 sweeps the drive shaft 180, and separates from the drive shaft 180 while contacting the free end 180b3 (fig. 22 (d)). After that, the cartridge B is taken out from the main assembly a by a process reverse to the mounting process described in fig. 17.

As is apparent from the above description, the pre-engagement angular position has a greater angle with respect to the axis L1 than the disengagement angular position has with respect to the axis L1. In this way, it is ensured that the free end position (a portion of the coupling 150) 150a1 sweeps over the free end 180b3 when the coupling is engaged in the pre-engaged position, taking into account the dimensional tolerances of the components. This is because: in the pre-engagement angular position, there is a gap between the coupler 150 and the free end 180b3 (fig. 19 (b)). In contrast, when the coupling is disengaged, the axis L2 is inclined toward the disengagement angular position as the cartridge B is removed. To this end, the free end 150a3 of the coupler 150 follows the free end 180b 3. In other words, the upstream side of the coupling 150 with respect to the cartridge takeout direction X6 and the free end portion 180b of the drive shaft 180 are substantially at the same position (fig. 22 (c)). Thus, the angle with respect to the axis L1 is greater at the pre-engagement angular position than at the disengagement angular position.

Further, similarly to the case of mounting the cartridge B to the main assembly a, the cartridge B can be taken out from the main assembly a regardless of the phase of the coupling 150 and the pin 182.

As described hereinabove, in the state in which the cartridge B is set in the main assembly a, a part of the coupling 150 (the free end position 150a1) is located behind the drive shaft 180 as viewed from the direction opposite to the taking-out direction X6 (fig. 19 (d)). Also, when the cartridge B is detached from the main assembly a, the coupling 150 performs the following movement. When the cartridge B is moved in the direction substantially perpendicular to the axis L1, the coupling 150 is moved, being inclined from the rotational force transmitting angular position to the disengaging angular position, so that a part of the coupling 150 (the free end position 150a1) bypasses the drive shaft 180. In the state of mounting the cartridge B to the main assembly a, the coupling 150 receives the rotational force from the driving shaft to rotate at its rotational force transmitting angular position. More specifically, the rotational force transmitting angular position is an angular position for transmitting the rotational force of the rotating developing roller 110 to the developing roller 110. Fig. 21 shows a state where the coupling 150 is in the rotational force transmitting angular position.

The pre-engagement angular position of the coupling 150 is an angular position of the coupling 150 relative to the axis L1 before the coupling 150 is to engage the drive shaft 180, when the cartridge B is mounted to the main assembly a. More specifically, it is an angular position with respect to the axis L1 at which the downstream-side free end portion 150a1 of the coupling 150 can sweep the drive shaft 180 in the mounting direction of the cartridge B.

The disengaging angular position of the coupling 150 is an angular position of the coupling 150 with respect to the axis L1 when the coupling 150 is disengaged from the drive shaft 180 with the cartridge B removed from the main assembly a. More specifically, as shown in fig. 22, it is an angular position with respect to the axis L1 at which the free end 150A3 of the coupling 150 can pass over the drive shaft 180 in the direction of removal of the cartridge B.

The included angle θ 2 between the axis L2 and the axis L1 is larger in the pre-engagement angular position or the disengagement angular position than the included angle θ 1 between the axis L2 and the axis L1. The angle θ 1 is preferably zero. However, according to this embodiment, if the included angle θ 1 is less than about 15 degrees, smooth transmission of the rotational force can be achieved. Preferably, the included angle θ 2 is about 20-60 degrees.

As described hereinabove, the coupler is mounted so that it can tilt relative to the axis L1. And, in response to the removal operation of the cartridge B, the coupling 150 is tilted. In this way, the coupling 150 in the overlapped state with the drive shaft 180 with respect to the direction of the axis L1 can be separated from the drive shaft 180. More specifically, the cartridge B moves in a direction substantially perpendicular to the axial direction L3 of the drive shaft 180. Thus, the coupling 150 in a state of covering the driving shaft 180 can be separated from the driving shaft 180.

In the above description, as the cartridge B is moved in the take-out direction X6, the receiving surface 150f or the projection 150d of the coupling 150 contacts the free end portion 180B. Thus, the axis L2 starts to incline (move) toward the upstream side with respect to the take-out direction. However, this is not necessarily the case in this embodiment. For example, a structure may be adopted such that a thrust force (elastic force) is applied in advance to the upstream side of the coupling 150 with respect to the taking-out direction. And, in response to the movement of the cartridge B, the axis L2 starts to tilt (move) toward the downstream side with respect to the take-out direction by the urging force with respect to the coupling 150. The free end 150a3 sweeps past the free end 180b3 so that the coupling 150 is decoupled from the drive shaft 180. In other words, the coupling can be separated from the drive shaft 180 without contact between the upstream (with respect to the extraction direction of the coupling 150) receiving surface 150f or the projection 150d and the free end portion 180 b. Therefore, if the axis L2 can be inclined with the removal operation of the cartridge B, any structure may be adopted.

Immediately before the coupling 150 is to be mounted on the drive shaft 180, the driven portion of the coupling 150 is inclined toward the downstream side with respect to the mounting direction. In other words, the coupling 150 is moved to the pre-engagement angular position in advance.

The pivoting in the plane of the drawing of fig. 22 has been described, but may also include rotation, similar to the case of fig. 19.

As described above, the axis L2 of the coupling 150 may be inclined in all directions with respect to the axis L1 of the developing roller 110 (fig. 11).

More specifically, axis L2 may be inclined in any direction relative to axis L1. However, with the coupling 150, the axis L2 need not be capable of being linearly inclined by a predetermined angle in any direction within a range of 360 degrees. In this case, for example, the opening 150g is formed wider in the circumferential direction. With this opening, when the axis L2 is inclined with respect to L1, the coupling 150 can rotate by a small angle about the axis L2 even in the case where the coupling cannot be linearly inclined to a predetermined angle. In this way, the coupling 150 can be inclined at a predetermined angle. In other words, if necessary, the amount of clearance in the rotational direction of the opening 150g may be appropriately selected.

In this way, the coupling 150 can rotate (oscillate) over substantially the entire circumference with respect to the axis L1 of the developing roller 110. More specifically, the coupling 150 is pivotable substantially over the entire circumference with respect to the developing roller 110.

As is readily apparent from the above description, the coupling 150 is rotatable substantially over the entire circumference relative to the axis L1.

Here, the rotation of the coupling does not mean that the coupling itself rotates about its axis L2, but means that the inclined axis L2 rotates about the axis L1 of the developing roller 110. However, it is not excluded that the coupling 150 itself rotates about the axis L2 within the actually provided clearance or clearance range.

More specifically, the coupling 150 is rotatable so that the free end of the driven portion 150a draws a circle having a center on the axis L2 when the end of the driving portion 150b on the developing roller 110 side is positioned on the axis L2.

Further, the coupling 150 is provided on the end of the developing roller 110, pivotable substantially in all directions with respect to the axis L1. In this way, the coupling 150 can be smoothly pivoted among the pre-engagement angular position, the rotational force transmitting angular position and the disengaging angular position.

Here, the pivoting in substantially all directions is defined as follows. More specifically, when the user mounts the cartridge B to the main assembly a, the coupling 150 can be pivoted to the rotational force transmitting angular position regardless of the stop phase of the driving shaft 180 provided with the rotational force applying portion.

Further, when the user demounts the cartridge B from the main assembly a, the coupling 150 can be pivoted to the disengaging angular position regardless of the stop phase of the drive shaft 180.

Further, the coupling 150 has a gap between the rotational force transmitting portion (e.g., the pin 155) and the rotational force transmitted portion (e.g., the rotational force transmitting surfaces 153h1, 153h2) engaged with the rotational force transmitting portion, so that the coupling can be inclined substantially in all directions with respect to the axis L1. In this way, the coupling 150 is mounted to the end of the developing roller 110. Thus, the coupling 150 may be inclined in substantially all directions relative to the axis L1. As described above, the coupling of this embodiment is mounted such that its axis L2 can be moved obliquely in any direction with respect to the axis L1 of the developing roller 110. Here, the tilting (moving) includes, for example, pivoting, swinging, and rotating as described above.

Referring to fig. 23 to 24, a modified example of the coupling is described.

Fig. 23 shows a first modification example. The driving portion 1150b of the coupling 1150 of this modified example has an enlarged shape similar to the driven portion 1150 a. The developing shaft 1153 is coaxial with the developing roller.

The developing shaft 1153 has a cylindrical portion 1153 a; the diameter of the developing shaft 1153 is about 5-15mm in consideration of material, load, and interval. The cylindrical portion 1153a is fixed to an engaging portion (not shown) of the developing roller flange by press-fitting, bonding, insert molding, or the like. Thus, as described below, the developing shaft 1153 transmits the rotational force from the main assembly a to the developing roller 110 through the coupling 1150. Its cylindrical portion 1153a has a free end 1153 b. Free end 1153b has a spherical configuration such that when axis L2 of coupler 1150 is tilted, free end 1153b may also be smoothly tilted. In the vicinity of the free end of the developing shaft 1153, in order to receive the rotational force from the coupling, a drive transmission pin (rotational force transmitting portion, rotational force receiving portion) 1155 extends in a direction intersecting the axis L1 of the developing shaft 153.

The pin 1155 is made of metal, and is fixed with respect to the developing shaft 1153 by press-fitting, bonding, or the like. The position thereof may be any as long as it is a position where a rotational force is transmitted (in a direction intersecting the axis line L1 of the developing shaft 153 (developing roller 110)). Preferably, the pin may pass through the center of the spherical surface of the free end 1153b of the visualization shaft 1153.

The structure of the driven portion 1150a of the coupling 1150 is the same as that described above, and thus description is omitted for the sake of brevity.

The opening 1150g has a rotational force transmitting surface (rotational force transmitting portion) 1150 i. In a state where the coupler is set in the cartridge B, when the opening 1150i has a conical shape as an enlarged portion, it is enlarged to a side having the developing shaft 153. By the rotation of the coupling 1150, the rotational force transmitting surface 1150i pushes the pin 1155 to transmit the rotational force to the developing roller 110.

In this way, regardless of the rotational phase of the developing roller 110 in the cartridge B, the coupling 1150 is able to pivot (move) with respect to the axis L1 between the rotational force transmitting angular position, the pre-engagement angular position, and the disengaging angular position without being obstructed by the free end portion of the developing shaft 1153. In the illustrated example, the receiving surface 1150i has a standby opening 1150g (1150g1, 1150g 2). The coupling 1150 is mounted to the developing shaft 1153 such that the pin 1155 is received in the opening 1150g1 or 1150g 2. The size of the opening 1150g1 or 1150g2 is larger than the outer diameter of the pin 1155. In this way, regardless of the rotational phase of the developing roller 110 in the cartridge B, the coupling 1150 can pivot (move) between the rotational force transmitting angular position and the pre-engagement angular position (or the separation angular position) without being hindered by the pin 1155.

Also, by the rotation of the coupling 1150, the rotational force transmitting surface 115i pushes the pin 1155, thereby transmitting the rotational force to the developing roller 110.

Referring to fig. 24, a second modified example is described.

In the above-described embodiment, the drive shaft receiving surface or the developing shaft receiving surface of the coupling is conical. In this embodiment, a different structure is adopted.

The coupling 12150 shown in fig. 24 has three main parts similar to the coupling 150 shown in fig. 6. More specifically, the coupling 12150 has a driven portion 12150a that receives rotational force from the drive shaft 180, a driving portion 12150b that transmits the rotation to the developing shaft 153, and an intermediate portion 12150c that connects the driven portion 12150a and the driving portion 12150b (fig. 24 (c)).

The driven portion 12150a and the driving portion 12150b have a drive shaft insertion opening 12150m enlarged toward the drive shaft 180 and a developing shaft insertion opening 12150v enlarged toward the developing shaft 153 with respect to the axis L2, respectively (fig. 24 (b)). The opening 12150m and the opening 12150v constitute enlarged portions. The openings 12150m and 12150v are constituted by the drive shaft receiving surfaces 12150f and the developing shaft receiving surfaces 12150i in the shape of horns. The receiving surfaces 12150f and 12150i have recesses 12150x, 12150z (fig. 24). The recess 12150z opposes the free end of the drive shaft 180 when the rotational force is transmitted. More specifically, the recess 12150z covers the free end of the drive shaft 180.

As described hereinabove, the developing shaft receiving surface of the coupling has an enlarged shape, and therefore, the coupling can be mounted for tilting movement with respect to the axis of the developing shaft. Further, the drive shaft receiving surface of the coupling has an enlarged shape, and therefore, the coupling can be tilted without interfering with the drive shaft at the time of the mounting operation or the taking-out operation of the cartridge B. Thus, in this embodiment, effects similar to those of the first embodiment or the second embodiment can be obtained.

The structures of the openings 12150m, 12250m and 12150v, 12250v may each be a combination of a trumpet shape, a bell shape, and the like.

Referring to fig. 25, another embodiment of a drive shaft is described. Fig. 25 is a perspective view of the drive shaft and the development drive gear.

As shown in fig. 25, the free end of the drive shaft 1180 has a flat surface 1180 b. In this case, the structure of the drive shaft is simple, and therefore, the manufacturing cost can be reduced.

As shown in fig. 25(b), the rotational force applying part (drive transmitting part) 1280(1280c1, 1280c2) may be integrally molded with the drive shaft 1280. In the case where the drive shaft 1280 is a molded resin part, the rotational force applying portion may be integrally molded. In this case, the cost can be reduced. Further, a flat surface portion is indicated by 1280 b.

A method of positioning the developing roller 110 in the direction of the axis L1 will be described below. Here, for example, a coupling (fig. 24) which expands toward the developing roller in the axial direction is described, which is similar to the coupling of the first modified example. However, the present invention can also be applied to the coupling of the first embodiment.

The coupling 1350 has chamfered surfaces (inclined surfaces) 1350e, 1350 h. The tapered surfaces 1350e, 1350h generate thrust when the drive shaft 181 rotates. With this urging force, the coupling 130 and the developing roller 110 are correctly positioned in the direction of the axis L1. Another description is made with reference to fig. 26 and 27. Fig. 26 is a perspective view and a top view showing only the coupling. Fig. 27 is an exploded perspective view showing the drive shaft, the developing shaft, and the coupling.

As shown in fig. 26(b), the taper of the rotational force receiving surface 1350e (1350e1 to 1350e4, inclined surface, rotational force receiving portion) with respect to the axis L2 is α 5. When the drive shaft 180 rotates in the direction T1, the pin 182 and the rotational force receiving surface 1350e contact each other. Next, a component force is applied to the coupler 1350 in the direction T2 to move it in that direction. And, the coupling 1350 is not moved in the direction of the axis L2 until the drive shaft receiving surface 1350f (fig. 27a) contacts the free end 180b of the drive shaft 180. Thus, the orientation relative to axis L2 determines the position of coupling 1350. Further, the free end 180b of the drive shaft 180 is spherical. The receiving surface 1350f is conical. For this reason, the position of the driven portion 1350a relative to the drive shaft 180 is determined in the direction perpendicular to the axis L2. Further, in the case where the coupling 1350 is attached to the developing roller 110, the developing roller 110 is also moved in the axial direction by the force applied in the direction T2. In this case, the position of the developing roller 110 in the longitudinal direction with respect to the main assembly a is also determined. The developing roller 110 is mounted with a clearance in the longitudinal direction in the cartridge frame.

Further, as shown in fig. 26(c), the taper angle of the rotational force transmitting surface (rotational force transmitting portion) 1350h with respect to the axis L2 is α 6 (inclined surface). When the coupling 1350 rotates in the direction T1, the transmission surface 1350h and the pin 1155 contact each other. And, the transfer surface 1350h pushes the pin 1155. Next, a force component is applied to pin 1155 in direction T2 to move it in direction T2. The developing shaft 1153 does not move until the free end 1153b of the developing shaft 1153 contacts the developing shaft receiving surface 1350i of the coupling 1350 (fig. 27 (b)). Thus, the position of the developing shaft 1153 (developing roller) is determined in the direction of the axis L2. The developing shaft receiving surface 1350i is conical, and the free end 1153b of the developing shaft 1153 is spherical. The position of the driving portion 1350b relative to the developing shaft 1153 is determined in the direction perpendicular to the axis line L2.

The taper angles α 5, α 6 are selected so that a force sufficient to move the coupling and the developing roller in the pushing direction can be generated. This force may be different depending on the torque required for the developing roller 110. However, if other ways of positioning it in the pushing direction are used, the taper angles α 5, α 6 may be smaller.

As described hereinabove, the coupling 1350 has a tapered portion for generating the retracting thrust force in the direction of the axis L2 and a conical surface for positioning in the direction perpendicular to the axis L2. In this way, the position of the coupling 1350 in the direction of the axis L1 and the position in the vertical direction can be determined simultaneously. Further, the coupling 1350 can reliably transmit the rotational force. Compared with the case where the rotational force receiving surface (rotational force receiving portion) or the rotational force transmitting surface (rotational force transmitting portion) of the coupling 1350 does not have the above-described taper angle, the following effects are provided. In the present embodiment, it is possible to stabilize the contact between the pin 182 (rotational force applying portion) of the drive shaft 180 and the rotational force receiving surface 1350e of the coupling 1350. Further, it is possible to stabilize the contact between the pin (rotational force transmitted portion 1155) of the developing shaft 1153 and the transmission surface (rotational force transmitting portion) 1350h of the coupling 1350.

However, the above-described tapered surface (inclined surface) and the above-described conical surface of the coupling 1350 are not essential. For example, instead of the above-described chamfered portion, a member for applying a thrust force in the direction of the axis L2 may be added.

Referring to fig. 28, a regulating member for regulating the inclination direction of the coupler with respect to the cartridge B is described. Fig. 28(a) is a side view showing a main part of the cartridge driving side. Fig. 28(b) is a sectional view taken along line S7-S7 in fig. 28 (a). For example, a description is given of a coupling (fig. 24) of a first modified example. In the coupling of the first modified example, the drive portion is enlarged toward the developing roller in the axial direction. However, this embodiment can also be applied to the coupling of the first embodiment. The coupling of the first embodiment has a spherical drive portion.

In this embodiment employing the regulating member, the coupling 1150 and the drive shaft 180 can be further reliably engaged.

In this embodiment, the developing support member 1557 has regulating portions 1557h1, 1557h2 as regulating members. The swinging direction of the coupling 115 with respect to the cartridge B can be regulated by this regulating member. The regulating portion 1557h1 or 1557h2 contacts the flange portion 1150j to regulate the swinging direction of the coupling 1150. The regulating portions 1557h1 and 1557h2 are provided so as to be parallel to the mounting direction X4 of the cartridge B immediately before the coupling 1150 engages the drive shaft 180. Further, the interval D6 therebetween is slightly larger than the outer diameter D7 of the driving section 1150b of the coupling 1150 (fig. 28 (D)). Thus, the coupling 1150 can be tilted only toward the mounting direction X4 of the cartridge B. Further, the coupling 1150 may be inclined in all directions with respect to the developing shaft 1153. For this reason, the coupling 1150 can be inclined to the direction of regulation regardless of the phase of the developing shaft 1153. Accordingly, the drive shaft 180 can be more reliably accommodated in the opening 1150m of the coupling 1150. In this way, the coupling 1150 can be further reliably engaged with the drive shaft 180.

Referring to fig. 29, another structure for regulating the inclination direction of the coupling is described. Fig. 29(a) is a perspective view showing the inside of the driving side of the main assembly. Fig. 29(b) is a side view of the cartridge viewed from the upstream side in the mounting direction X4.

In the above description, the regulating portions 1557h1, 1557h2 are provided in the cartridge B. In this embodiment, a part of the mounting guide 1630R1 of the driving side of the main assembly a is a rib-like regulating portion 1630R1 a. Thus, the regulating portion 1630R1a is a regulating member for regulating the swinging direction of the coupling 1150. Also, when the user inserts the cartridge B, the outer periphery of the intermediate portion 1150c of the coupling 1150 contacts the upper surface 1630R1a-1 of the regulating portion 1630R1 a. Thus, coupler 1150 is guided by upper surface 1630R1 a-1. Thus, the tilt direction of the coupling 1150 is regulated. Further, similarly to the above-described embodiment, the coupling 1150 can be inclined to the regulating direction regardless of the phase of the developing shaft 1153.

In the embodiment shown in fig. 29(a), the regulating portion 1630R1a is provided below the coupling 1150. However, similarly to the regulating portion 1557h2 shown in fig. 28, more reliable regulation can be achieved when a regulating portion is added above.

As described hereinabove, it may be combined with a structure in which the regulating portion is provided in the cartridge B. In this case, reliable policing can be further achieved.

Further, a shaft is provided substantially coaxially with the axis of the coupling 150 (fig. 6) in the first embodiment, and another portion of the cartridge (e.g., a support member) may be used to regulate the shaft.

However, in this embodiment, a member for regulating the inclination direction of the coupling may not be provided. For example, the coupling 1150 is inclined toward the downstream side of the cartridge B with respect to the mounting direction. The drive shaft receiving surface 1150f of the coupling is enlarged. In this way, the drive shaft 180 and the coupling 1150 may engage each other.

In the above description, the pre-engagement angular position of the coupling 1150 is at a greater angle relative to the axis L1 than the disengagement angular position. However, this is not necessarily so.

This is described with reference to fig. 30. Fig. 30 is a longitudinal sectional view showing a process of taking out the cartridge B from the main assembly a. For example, the coupling of the first modified example is taken as an example. However, this may also be applied to the coupling of the first embodiment.

The angle of the separating angular position (fig. 30c) of the coupling 1750 with respect to the axis L1 in the process of taking out the cartridge B from the main assembly a may be as follows. The angle may be equal to the angle of the coupling 1150 relative to the axis L1 in the pre-engagement angular position when the coupling 1150 is engaged with the drive shaft 180. Here, the detaching process of the coupling 1150 is described with reference to fig. 30(a) - (b) - (c) - (d).

More specifically, when the free end 1150A3 sweeps over the free end 180b3 of the drive shaft 180 with respect to the upstream side in the extraction direction X6 of the coupling 1150, the distance between the free end 1150A3 and the free end 180b3 is equal to the distance at the pre-engagement angular position. With this arrangement, the coupling 1150 can be separated from the drive shaft 180.

For other operations when the cartridge B is taken out, the same operations as those described above can be applied. For this reason, the description is omitted for simplicity.

In the foregoing operation, when the cartridge B is mounted to the main assembly a, the coupling free end on the downstream side with respect to the mounting direction is closer to the developing shaft than the free end of the drive shaft 180. However, this is not necessarily so.

This is described with reference to fig. 31. For example, the coupling of the first modified example is taken as an example. However, this may also be applied to the coupling of the first embodiment.

Fig. 31 is a longitudinal sectional view showing a process of mounting the cartridge B. The mounting of the cartridge B is performed in the order of (a) - (B) - (c) - (d). In the state shown in fig. 31(a), in the direction of the axis L1, the free end position 1150a1 downstream with respect to the mounting direction X4 is closer to the pin 182 (rotational force applying portion) than the free end 180b3 of the drive shaft. In the state shown in fig. 31(b), the free end position 1150a1 contacts the free end 180b 3. At this time, the free end position 1150a1 moves along the free end 180b toward the developing shaft 1153. The free end position 1150a1 sweeps over the free end 180b3 (at which time the coupling 1150 is in the pre-engaged angular position) (fig. 31 (c)). Finally, the coupling 1150 and the drive shaft 180 are engaged with each other (rotational force transmitting angular position) (fig. 31 (d)).

In the developing cartridge using such a coupling, the following effects are provided in addition to the effects described above.

(1) An external force is applied to the cartridge by the meshing force between the gears. In the case where the external force is directed so that the developing roller and the photosensitive drum are separated from each other, image quality may be deteriorated. Therefore, the position of the cartridge gear or the swing center is restricted to generate a moment in a direction to bring the developing roller close to the photosensitive drum. For this reason, the design range is narrow. Therefore, the main assembly or the cartridge may be large. However, according to this embodiment, the range of the driving input position is wide. Therefore, the main assembly or the cartridge can be miniaturized.

(2) In the case of the operatively connecting gears between the cartridge B and the main assembly, in order to prevent the tooth tops between the gears from bearing when the cartridge is mounted, it is necessary to consider the positions of the gears so that the gears approach beyond the tangential direction. For this reason, the design range may be narrow and the main assembly or the cartridge may be large. However, according to this embodiment, the range of the driving input position is wide. Therefore, the main assembly or the cartridge can be miniaturized.

An example according to the present embodiment will be described.

The maximum outer diameter of the driven part 150a of the coupling 150 is Z4, the diameter of a virtual circle C1 contacting the inner end surfaces of the protrusions 150d1, 150d2, 150d3, 150d4 is Z5, and the maximum outer diameter of the driving part 150b is Z6 (fig. 6(d), (f)). The receiving surface 150f of the coupling 150 has an angle α 2. The drive shaft 180 has a shaft diameter Z7 and the pin 182 has a shaft diameter Z8 and a length Z9 (fig. 19). With respect to the axis L1, the angle at the rotational force transmitting angular position is β 1, the angle at the pre-engagement angular position is β 2, and the angle at the disengaging angular position is β 3. In this case, for example:

z 4-13 mm, z 5-8 mm, z 6-10 mm, z 7-6 mm, z 8-2 mm, z 9-14 mm, α 1-70 degrees, β 1-0 degrees, β 2-35 degrees, β 3-30 degrees.

It has been demonstrated that with the above-described settings, the coupling 150 can be engaged with the drive shaft 180. However, similar operation may be achieved using other settings. The coupling 150 can transmit the rotational force to the developing roller 110 with high accuracy. The above numerical values are examples, and the present invention is not limited to these numerical values.

In this embodiment, the pin (rotational force applying portion) 182 is provided at a position within 5mm from the free end of the drive shaft 180. The rotational force receiving surface (rotational force receiving portion) 150e on the projection 150d is provided at a position within 4mm from the free end of the coupling 150. In this way, the pin 182 is disposed on the free end of the drive shaft 180. The rotational force receiving surface 150e is provided on the free end portion of the coupling 150.

Thus, the drive shaft 180 and the coupling 150 can be smoothly engaged with each other when the cartridge B is mounted to the main assembly a. More specifically, the pin 182 and the rotational force receiving surface 150e can be smoothly engaged with each other.

When the cartridge B is dismounted from the main assembly a, the drive shaft 180 and the coupling 150 can be smoothly separated from each other. More specifically, the pin 182 and the rotational force receiving surface 150e can be smoothly separated from each other.

These values are examples and the present invention is not limited to these values. However, the above-described effects can be effectively provided by providing the pin (rotational force applying portion) 182 and the rotational force receiving surface 150e in these numerical ranges.

As described above, according to the embodiment of the invention, the coupling 150 can be in the rotational force transmitting angular position and the pre-engagement angular position. Here, the rotational force transmitting angular position is an angular position for transmitting the rotational force of the rotating developing roller 110 to the developing roller 110. The pre-engagement angular position is a position inclined in a direction away from the axis L1 of the developing roller 110 from the rotational force transmitting angular position. The coupling 150 can also be in the disengaging angular position, which is a position inclined in a direction away from the axis L1 of the developing roller 110 from the rotational force transmitting angular position. When the cartridge B is dismounted from the main assembly a in the direction substantially perpendicular to the axis L1, the coupling 150 is moved from the rotational force transmitting angular position to the disengaging angular position. Thus, the cartridge B can be detached from the main assembly a. When the cartridge B is mounted to the main assembly a in the direction substantially perpendicular to the axis L1, the coupling 150 is moved from the pre-engagement angular position to the rotational force transmitting angular position. Thus, the cartridge B can be mounted to the main assembly a. This can be applied to the latter embodiment. However, in embodiment 2, only the case of detaching the cartridge B from the main assembly a will be described.

(example 2)

A second embodiment of the present invention is described with reference to fig. 32-36. For example, the coupling of the first modified example is taken as an example. However, the present embodiment is also applicable to, for example, the coupling of the first embodiment. With regard to the structure of the coupling, a person skilled in the art can select a suitable structure.

In the description of this embodiment, the same reference numerals as in embodiment 1 are given to elements having corresponding functions in this embodiment, and detailed description is omitted for simplicity. The same applies to all the following embodiments.

This embodiment is applicable only to the case of detaching the cartridge B from the main assembly a.

In the case of stopping the drive shaft 180 by the control operation of the main assembly a, the drive shaft 180 is stopped at a predetermined phase (predetermined orientation of the pin 182). The phase of the coupling 14150(150) is set to align with the phase of the drive shaft 180. For example, the position of the standby portion 14150k (150k) is aligned with the stop position of the pin 182. With this setting, at the time of mounting the cartridge B to the main assembly a, the coupling 14150(150) is in a state opposed to the drive shaft 180 without pivoting (swinging, rotating). By the rotation of the drive shaft 180, the rotational force is transmitted from the drive shaft 180 to the coupling 14150 (150). In this way, the coupling 14150(150) can be rotated with high accuracy.

However, the structure according to embodiment 2 of the present invention is effective when the cartridge B is dismounted from the main assembly a in the direction substantially perpendicular to the direction of the axis L3. Here, the pin 182 and the rotational force receiving surfaces 14150e1, 14150e2(150e) are engaged with each other. This is because: in order to disengage the coupling 14150(150) from the drive shaft 180, the coupling 14150(150) must pivot.

In embodiment 1 described above, the coupling 14150(150) is inclined (moved) at the time of mounting and dismounting the cartridge B relative to the main assembly a. Therefore, in mounting the cartridge B to the main assembly a by the above-described control of the main assembly a, it is not necessary to align the phase of the coupling 14150(150) with the phase of the stopped drive shaft 180 in advance.

The description is made with reference to the accompanying drawings.

Fig. 32 is a perspective and top view of the coupling. Fig. 33 is a perspective view showing the mounting operation of the cartridge. Fig. 34 is a plan view seen from the mounting direction in a state when the cartridge is mounted. Fig. 35 is a perspective view showing a driving stop state of the cartridge (developing roller). Fig. 36 is a longitudinal sectional view and a perspective view showing an operation of taking out the cartridge.

In this embodiment, a cartridge detachably mountable to a main assembly a having a control means (not shown) for controlling the phase of the stop position of the pin 182 will be described.

Referring to fig. 32, a coupling for the present embodiment is described.

The coupling 14150(150) includes three main portions. As shown in fig. 32(c), they are a driven portion 14150a for receiving a rotational force from the drive shaft 180, a driving portion 14150b for transmitting the rotational force to the developing shaft 153, and an intermediate portion 14150c for connecting the driven portion 14150a and the driving portion 14150 b.

The driven portion 14150a has a drive shaft insertion portion 14150m including two surfaces enlarged from the axis L2. The driving portion 14150b has a developing shaft insertion portion 14150v including two surfaces enlarged from the axis L2.

The insertion portion 14150m has drive shaft receiving surfaces 14150f1, 14150f2 of a tapered shape. Each end face has a protrusion 14150d1, 14150d 2. The protrusions 14150d1, 14150d2 are disposed on a circumference centered on the axis L2 of the coupling 14150. As shown, the receiving surface 14150f1 or 14150f2 constitutes a recess 14150 z. As shown in fig. 32(d), the projections 14150d1, 14150d2 have rotational force receiving surfaces (rotational force receiving portions) 14150e (14150e1, 14150e2) on the downstream side in the clockwise direction. The pin (rotational force applying portion) 182 contacts the receiving surfaces 14150e1, 14150e 2. Thus, the rotational force is transmitted to the coupling 14150. The spacing W between adjacent projections 14150d1-d2 is greater than the outer diameter of pin 182 so as to accommodate pin 182. This interval serves as a standby portion 14150 k.

The insert 14150v is constituted by two surfaces 14150i1, 14150i 2. The standby opening 14150g1 or 14150g2 is provided in the surface 14150i1, 14150i2 (fig. 32(a) and 32 (e)). In fig. 32(e), a rotational force transmitting surface (rotational force transmitting portion) 14150h (14150h1, 14150h2) is provided on the upstream side of the openings 14150g1, 14150g2 in the clockwise direction (fig. 32(b), (e)). As described hereinabove, the pin (rotational force transmitted portion) 155a contacts the rotational force transmitting surfaces 14150h1, 14150h 2. Thus, the rotational force is transmitted from the coupling 14150 to the developing roller 110.

With this structure of the coupling 14150, in a state where the cartridge is mounted to the main assembly, the coupling covers the free end of the drive shaft. In this way, the effects as described below are provided.

The coupling 14150 has a structure similar to that of the first modified example, and is tiltable (movable) in all directions with respect to the developing shaft 153.

The mounting operation of the coupler is described with reference to fig. 33 and 34. Fig. 33(a) is a perspective view showing a state before the coupling is mounted. Fig. 33(b) is a perspective view showing the coupling in the engaged state. Fig. 34(a) is a plan view seen from the mounting direction. Fig. 34(b) is a plan view.

The axis L3 of the pin (rotational force applying portion) 182 is made parallel to the mounting direction X4 by the control device described above. For the cartridge, the phases are aligned (fig. 33(a)) so that the acceptance surfaces 14150f1, 14150f2 are opposed to each other in the direction perpendicular to the mounting direction X4. As shown, for example, as a structure for aligning the phases, one of the receiving surfaces 14150f1, 14150f2 is aligned with an alignment mark 14157z provided on the support member 14157. The above-described operation is performed when the cartridge is shipped from the factory. However, the user may perform this operation before mounting the cartridge B to the main assembly. In addition, other phase alignment approaches may be used. In this way, the coupling 14150 and the drive shaft 180 (pin 182) do not interfere with each other, as shown in fig. 34 (a). For this reason, the coupling 14150 and the drive shaft 180 are in an engageable positional relationship (fig. 33 (b)). The drive shaft 180 rotates in the direction X8 with the pin 182 contacting the receiving surfaces 14150e1, 14150e 2. Thus, the rotational force is transmitted to the developing roller 110.

Referring to fig. 35 and 36, the operation of disengaging the coupling 14150 from the drive shaft 180 following the operation of taking out the cartridge B from the main assembly a will be described. A control device (not shown) stops the pin 182 at a predetermined phase with respect to the drive shaft 180. From the viewpoint of facilitating mounting of the cartridge B, it is desirable to stop the pin 182 at a position parallel to the cartridge takeout direction X6 (fig. 35 (B)). Fig. 36 shows an operation when the cartridge B is taken out. In this state (fig. 36(a1) and (b1)), the axis L2 of the coupling 14150 is substantially coaxial with respect to the axis L1 at the rotational force transmitting angular position. Similarly to the case of the mounting cartridge B, at this time, the coupling 14150 can be tilted (moved) in all directions with respect to the developing shaft 153 (fig. 36(a1) and (B1)). For this reason, with the taking-out operation of the cartridge B, the axis L2 is inclined with respect to the axis L1 in the direction opposite to the taking-out direction. More specifically, the cartridge B is detached in a direction (the direction of arrow X6) substantially perpendicular to the axis L3. During the cartridge removal, the axis L2 is inclined to a position (separation angular position) at which the free end 14150A3 of the coupling 14150 follows the free end of the drive shaft 180. Alternatively, it is inclined up to the side of the axis L2 located with respect to the free end portion 180b3 to the developing shaft 153 (fig. 36(a2) and (b 2)). In this state, the coupling 14150 sweeps adjacent the free end 180b 3. In this way, the coupling 14150 is detached from the drive shaft 180.

In the state in which the cartridge B is mounted to the main assembly a, a part of the coupling 14150 (the free end 14150A3) is located behind the drive shaft 180 as viewed from the direction opposite to the taking-out direction X6 in which the cartridge B is dismounted from the main assembly a (fig. 36(a 1)). Also, when the cartridge B is removed from the main assembly a, the coupling 14150 performs the following movement when the cartridge B is moved in a direction substantially perpendicular to the axis L1 of the developing roller 110. More specifically, the coupling 150 is moved from the rotational force transmitting angular position to the disengaging angular position, so that the portion (the free end 14150a3) of the coupling 150 bypasses the drive shaft 180.

As shown in fig. 35(a), the axis of the pin 182 may stop in a direction perpendicular to the cartridge removing direction X6. In other words, the pin 182 is normally stopped at the position shown in fig. 35(b) by a control operation of a control device (not shown). However, when the power of the apparatus (printer) is turned off and the control device (not shown) is not operated, the pin 182 may stop at the position shown in fig. 35 (a). However, even in this case, the axis L2 may be inclined with respect to the axis L1 to allow disassembly. In the rest state of the device, the pin 182 is downstream of the projection 14150d2 in the extraction direction X6. To this end, the free end 14150A3 of the projection 14150d1 of the coupler is swept sideways closer to the developing shaft 153 than the pin 182 by the inclination axis L2. In this way, the coupling 14150 is detachable from the drive shaft 180.

In the case where the coupling 14150 is engaged with the drive shaft 180 in a certain method at the time of mounting the cartridge B and there is no means for controlling the phase of the drive shaft, the cartridge may be taken out by inclining the axis L2 with respect to the axis L1. In this way, the coupling 14150 can be separated from the drive shaft 180 only by the cartridge removing operation.

As described hereinabove, embodiment 2 is effective even in the case where only the detachment of the cartridge B from the main assembly a is considered.

As described above, embodiment 2 has the following structure.

The cartridge B is dismounted from the main assembly a having the drive shaft 180 by moving the cartridge B in a direction substantially perpendicular to the direction of the axis L3 of the drive shaft 180, which has the pin (rotational force applying portion) 182. The cartridge B has the developing roller 110 and the coupling 14150.

I > > the developing roller 110 is rotatable about its axis L1, and develops an electrostatic latent image formed on the photosensitive drum 7. II > > the coupling 14150 engages the pin 182 to receive the rotational force for rotating the developing roller 110. The coupling 14150 can be at a rotational force transmitting angular position for transmitting the rotational force of the rotating developing roller 110 to the developing roller 110 and at a disengaging angular position for disengaging the coupling 14150 from the drive shaft 180, at which the coupling is inclined from the rotational force transmitting angular position.

When the cartridge B is dismounted from the main assembly a in the direction substantially perpendicular to the axis L1 of the developing roller 110, the coupling 14150 is moved from the rotational force transmitting angular position to the disengaging angular position.

(example 3)

Embodiment 3 to which the present invention is applied is described with reference to fig. 37 to 41. The structure of the coupling is the same as that described in embodiment 2.

Fig. 37 is a sectional view showing a state where the door of the apparatus main assembly a2 is opened. Fig. 38 is a perspective view showing a state in which the door of the apparatus main assembly a2 is opened. Fig. 39 is an enlarged view of the driving side surface of the cartridge. Fig. 40 is a perspective view from the driving side of the cartridge. Fig. 41 is a schematic diagram showing, for simplicity, two states in a single drawing, including a state immediately before the cartridge is to be inserted into the apparatus main assembly and a state before the cartridge is mounted to a predetermined position.

In this embodiment, a case where the cartridge is mounted toward the lower portion in the vertical direction, for example, as a clamshell type image forming apparatus will be described. A typical clamshell imaging device is shown in fig. 37. The apparatus main assembly a2 can be divided into a lower casing D2 and an upper casing E2. The upper casing E2 has a door 2109 and an exposure part 2101 inside the door 2109. For this reason, when the upper case E2 is opened upward, the exposure member 2101 is retracted. Then, the upper portion of the cartridge mounting portion 2130a is opened. Therefore, the user only needs to lower cartridge B2 in the vertically downward direction (direction X42 in the drawing) when mounting cartridge B2 in mount portion 2130 a. In this way, the mounting of the cartridge is made easier. Further, jam clearance near the fixing member 105 can be performed from above the apparatus. Therefore, jam clearance can be easily performed. Here, jam clearance represents an operation for removing the recording material (medium) 102 jammed or jammed while being conveyed.

Next, the mounting portion 2130a will be described. As shown in fig. 38, the image forming apparatus (apparatus main assembly) a2 includes a driving side mounting guide portion 2130R as a mounting member 2130 and a non-driving side mounting guide portion (not shown) opposed to the driving side mounting guide portion 2130R. The mounting portion 2130a is a space surrounded by the facing guide portions. In a state where the cartridge B2 is mounted in the mounting portion 2130a, the rotational force is transmitted from the apparatus main assembly a2 to the coupling 150.

The mounting guide 2130R is provided with a groove 2130b in a substantially vertical direction. Further, a contact portion 2130Ra for positioning the cartridge B2 at a predetermined position is provided at the lowermost portion of the mounting guide 2130R. Further, the drive shaft 180 protrudes from the groove 2130B so as to transmit the rotational force from the apparatus main assembly a2 to the coupling 150 when the cartridge B2 is positioned at the predetermined position. Further, in order to reliably position the cartridge B2 at a predetermined position, an urging spring 2188R is provided at a lower portion of the mounting guide 2130R. With the above structure, the cartridge B2 is positioned at the mounting portion 2130 a.

As shown in fig. 39 and 40, cartridge-side mounting guides 2140R1 and 2140R2 are provided on the cartridge B2. With these guide portions, the posture of the cartridge B2 is stabilized during the mounting process. The mounting guide 2140R1 is formed integrally with the developing device supporting member 2157. Further, the mounting guide portions 2140R2 are disposed vertically above the mounting guide portions 2140R 1. The mounting guide 2140R2 is provided on the support member 2157 in the shape of a rib.

Incidentally, the guide portions 2140R1 and 2140R2 of the cartridge B2 and the mounting guide portion 2130R provided to the apparatus main assembly a2 constitute the above-described guide structure. That is, the guide structure in this embodiment is the same as the guide structure described with reference to fig. 2 and 3. The same applies to the guide structure at the other end. Therefore, the cartridge B2 is movable in a direction substantially perpendicular to the direction of the axis L3 of the drive shaft 180 and is mounted to the apparatus main assembly a2 (mounting portion 2130 a). Further, the cartridge B2 is detachable from the apparatus main assembly a2 (mounting portion 2130 a).

As shown in fig. 41, when the cartridge B is mounted, the casing E2 is rotated clockwise about the shaft 2109 a. Then, the user moves the cartridge B2 upward of the casing D2. At this time, the coupling 150 is inclined downward by its own weight (see also fig. 39). That is, the axis L2 of the coupling 150 is inclined with respect to the axis L1 such that the driven portion 150a of the coupling 150 points downward (angular position before engagement).

In this state, by fitting the mounting guides 2140R1 and 2140R2 of the cartridge B2 to the mounting guide 2130R of the apparatus main assembly a2, the user moves the cartridge B2 downward. The cartridge B2 can thus be mounted to the apparatus main assembly a2 (mounting portion 2130a) by this operation alone. During this installation, the coupling 150 may engage the drive shaft 180, similar to that in embodiment 1 (fig. 19). In this state, the coupling 150 is in the rotational force transmitting angular position. That is, by moving the cartridge B2 in a direction substantially perpendicular to the direction of the axis L3 of the drive shaft 180, the coupling 150 engages the drive shaft 180. Further, at the time of detaching the cartridge B2, the coupling 150 can be separated from the drive shaft 180 only by the cartridge detaching operation, similarly to that in embodiment 1. That is, the coupling 150 moves from the rotational force transmitting angular position to the disengaging angular position (fig. 22). In this way, by moving the cartridge B2 in a direction substantially perpendicular to the direction of the axis L3 of the drive shaft 180, the coupling 150 is separated from the drive shaft 180.

As described above, in the case of mounting the cartridge downward to the apparatus main assembly a2, the coupling 150 is inclined downward by its own weight. To this end, the coupling 150 may be engaged with the drive shaft 180.

In this embodiment, a clamshell type image forming apparatus is described. However, the present invention is not limited thereto. For example, this embodiment is applicable to the case when the mounting path of the cartridge is directed downward. The installation path may also be non-linear downward. For example, the mounting path of the cartridge may be inclined downward in the initial stage and directed downward in the final stage. In short, the mounting path is required to be directed downward only immediately before the cartridge reaches the predetermined position (the mounting portion 2130 a).

(example 4)

Embodiment 4 to which the present invention is applied is described with reference to fig. 42 to 45. The structure of the coupling is the same as that described in embodiment 2. In this embodiment, a means of maintaining the axis L2 in an inclined state with respect to the axis L1 will be described.

Fig. 42 is an exploded perspective view showing a state where a coupling urging member (peculiar to this embodiment) is mounted to the developing device supporting member. Fig. 43(a) and 43(b) are exploded perspective views showing the developing device supporting member, the coupling, and the developing shaft. Fig. 44 is an enlarged perspective view showing a main portion of the cartridge driving side. Fig. 45(a) -45(d) are longitudinal sectional views showing a process in which the drive shaft engages the coupling.

As shown in fig. 42, the developing device supporting member 4157 has a holding hole 4157j in a rib 4157 e. In the holding hole 4157j, coupling urging members 4159a and 4159b are mounted as holding members for holding the inclination of the coupling 4150. The urging members 4159a and 4159B urge the coupling 4150 so that the coupling 4150 is inclined toward the downstream side with respect to the mounting direction of the cartridge B2. The urging members 4159a and 4159b are compression springs (elastic members). As shown in fig. 43(a) and 43(b), the urging members 4159a and 4159b urge the flange portion 4150j of the coupling 4150 in the direction of the axis L1 (the direction indicated by the arrow X13 in fig. 43 (a)). The contact position of the urging member with the flange portion 4150j is disposed on the downstream side of the center of the developing shaft 153 with respect to the mounting direction X4. For this reason, the axis L2 is inclined with respect to the axis L1 by the elastic force of the urging members 4159a and 4159b such that the driven portion 4150a side is directed to the downstream side with respect to the cartridge mounting direction X4 (fig. 44).

Further, as shown in fig. 42, at the coupling-side end portions of the urging members 4159a and 4159b, contact members 4160a and 4160b are provided. The contact members 4160a and 4160b contact the flange portion 4150 j. Therefore, the material for the contact members 4160a and 4160b is selected from materials having good slidability. With this material, as described later, the urging force (elastic force) of the urging members 4159a and 4159b does not affect the rotation of the coupling 4150 during the transmission of the rotational force. However, when the load acting on the rotation is sufficiently small and the coupling 4150 can smoothly rotate, the contact members 4160a and 4160b may also be omitted.

In this embodiment, two urging members are used. However, when the axis L2 may be inclined downward with respect to the axis L2 in the cartridge mounting direction X4, the number of pushing members may be changed. For example, in the case of a single urging member, the desired urging position is the most downstream position of the cartridge mounting position. Therefore, the coupling 4150 can be stably inclined toward the downstream direction in the mounting direction X4.

In this embodiment, a compression coil spring is used as the urging member. However, as the urging member, any material may be appropriately selected, such as a plate spring, a torsion spring, rubber, or sponge, as long as the material can generate an elastic force. However, the urging member requires a certain degree of stroke in order to tilt the axis L2. For this reason, it is desirable that the material of the urging member is a coil spring or the like capable of giving the stroke.

Next, an installation method of the coupling 4150 is described with reference to fig. 43(a) and 43 (b).

As shown in fig. 43(a) and 43(b), the pin 155 is inserted into the standby space 4150g of the coupling 4150. Then, a part of the coupling 4150 is inserted into the space 4157b of the developing device supporting member 4157. At this time, as described above, the urging members 4159a and 4159b press the predetermined portion of the flange portion 4157a through the contact members 4160a and 4160 b. Further, the supporting member 4157 is fixed to the developing device frame 118 with bolts or the like. Therefore, the urging members 4159a and 4159b can obtain a force urging the coupling 4150. Thus, the axis L2 is inclined with respect to the axis L1 (the state of fig. 44).

Next, an operation (as a part of the cartridge mounting operation) in which the coupling 4150 engages the drive shaft 180 is described with reference to fig. 45. Fig. 45(a) and 45(c) show a state immediately before engagement, and fig. 45(d) shows an engaged state. In the state shown in fig. 45(a), the axis L2 of the coupling 4150 is preliminarily inclined with respect to the axis L1 in the mounting direction X4 (angular position before engagement). By the inclination of the coupling 4150, in the direction of the axis L1, the end position 4150a1 on the downstream side with respect to the mounting direction X4 is positioned closer to the developing roller 110 than the end 180b 3. Further, the end position 4150a2 on the upstream side with respect to the mounting direction X4 is positioned at a position closer to the pin 182 than the end 180b 3. That is, as described above, the flange portion 4150j of the coupling 4150 is pushed by the pushing member 4159. For this reason, the axis L2 is inclined with respect to the axis L1 by the thrust.

Therefore, by moving the cartridge B in the mounting direction X4, the end surface 180B or end portion (main assembly side engaging portion) of the pin (rotational force applying portion) 182 contacts the drive shaft receiving surface 4150f or projection (cartridge side contacting portion) 4150d of the coupling 4150. Fig. 45(c) shows a state where the pin 182 is in contact with the receiving surface 4150 f. Then, by the contact force (mounting force of the cartridge), the axis L2 approaches the direction parallel to the axis L1. Meanwhile, the urging portion 4150j1 is urged by the elastic force of the spring 4159 provided on the flange portion 4150j, thereby moving in the direction in which the compression spring 4159 is compressed. Then, axis L1 and axis L2 are ultimately substantially in line with each other. Then, the cartridge 4150 is placed in a standby state to perform the transmission of the rotational force (rotational force transmitting angular position) (fig. 45 (d)).

After that, similarly to embodiment 1, the rotational force is transmitted from the motor 186 to the developing roller 110 through the drive shaft 180, the coupling 4150, the pin 155, and the developing shaft 4153. During the rotation, the urging force of the urging member 4159 is exerted on the coupling 4150. However, as described above, the urging force of the urging member 4159 is exerted on the coupling 4150 through the contact member 4160. For this reason, the coupling 4150 can rotate in a state where the load is not large. Further, when there is a margin for the driving torque of the motor 186, the contact member 4160 may be omitted. In this case, the coupling 4150 can accurately transmit the rotational force even when the contact member is not provided.

Further, when the cartridge B is detached from the apparatus main assembly a, the steps thereof are reversed from the mounting steps (fig. 45(d) -fig. 45(c) -fig. 45(B) -fig. 45 (a)). That is, the cartridge 4150 is always pushed toward the downstream side with respect to the mounting direction X4 by the pushing member 4159. For this reason, in the process of removing the cartridge B, the receiving surface 4150 contacts the end portion 182A of the pin 182 on the upstream side with respect to the mounting direction X4 (the state between fig. 45(d) and 45 (d)). Further, on the downstream side with respect to the mounting direction X4, a gap n50 is always formed between the transmitting (receiving) surface 4150f and the end 180b of the drive shaft 180. In the above-described embodiment, in the process of removing the cartridge, it is described that the receiving surface 4150f or the projection 4150d located on the downstream side in the cartridge mounting direction X4 contacts at least the end portion 180b of the drive shaft 180 (e.g., fig. 19). However, in this embodiment, even when the receiving surface 4150f or the projection 4150d on the downstream side does not contact the end portion 180B of the drive shaft 180, the coupling 4150 can be separated from the drive shaft 180 with the removal operation of the cartridge B. Then, also after the coupling 4150 is separated from the drive shaft 180, the axis L2 is inclined downward (the detaching angular position) with respect to the axis L1 in the mounting direction X4 by the urging force of the urging member 4159. That is, in this embodiment, the angle relative to the axis L1 at the pre-engagement angular position is equal to the angle relative to the axis L1 at the removal angular position. This is because the coupling 4150 is urged by the elastic force of the spring.

The urging member 4159 has the effect of inclining the axis L2 and regulating the direction in which the coupling 4150 inclines. That is, the urging member 4159 also serves as a regulating means that regulates the inclination direction of the coupling 4150.

As described above, in this embodiment, the coupling 4150 is urged by the urging force of the urging member 4159 provided on the support member 4157. Accordingly, the axis L2 is inclined with respect to the axis L1. Accordingly, the inclined state of the coupling 4150 is maintained. Therefore, the coupling 4150 can be reliably engaged with the drive shaft 180.

Incidentally, in this embodiment, the urging member 4159 is provided on the rib 4157e of the support member 4157, but is not limited thereto. For example, the urging member 4159 may be provided on other portions of the support member 4157 or on a member other than the support member as long as the member is fixed to the cartridge B.

Further, in this embodiment, the urging direction of the urging member 4159 is the direction of the axis L1. However, the urging direction may be any direction that enables the axis L2 to be inclined (moved) toward the downstream side with respect to the mounting direction X4 of the cartridge B.

Further, in this embodiment, the flange portion 4150j is located at the urging position of the urging member 4159. However, the urging position may be any position of the coupling as long as the axis L2 can be inclined toward the downstream side in the cartridge mounting direction.

(example 5)

Embodiment 5 to which the present invention is applied is described with reference to fig. 46 to 50. The structure of the coupling is as described above.

In this embodiment, another manner for inclining the axis L2 with respect to the axis L1 will be described.

Fig. 46(a1), 46(a2), 46(b1), 46(b2) are enlarged side views of the cartridge driving side. Fig. 47 is a perspective view showing a driving side of the apparatus main assembly guide. Fig. 48(a) and 48(b) are side views showing the relationship between the cartridge and the apparatus main assembly guide. Fig. 49(a) and 49(b) are schematic views of the relationship between the apparatus main assembly guide and the coupling as viewed from the upstream side in the mounting direction. Fig. 50(a) -50(f) are side views showing the mounting process.

Fig. 46(a1) and 46(b1) are side views of the cartridge viewed from the drive shaft side. Fig. 46(a2) and 46(b2) are side views of the cartridge seen from the side opposite to the drive shaft side. As shown in these drawings, the coupling 7150 is attached to the developing device supporting member 7157 in a state where the coupling 7150 can be inclined toward the downstream side in the attaching direction X4. Further, with respect to the inclination direction, the coupling 7150 can be inclined only toward the downstream side of the mounting direction X4. Further, in the state of fig. 46(a1), the axis L2 of the coupling 7150 is inclined at an angle α 60 with respect to the horizontal line. The reason why the coupling 7150 is inclined at the angle α 60 is as follows. The flange portion 7150j of the coupling 7150 is regulated by regulating portions 7157h1 and 7157h2 (fig. 46(a2)) as regulating means. For this reason, the coupling 7150 may be inclined upward at an angle α 60 with respect to the downstream side of the mounting direction.

Next, referring to fig. 47, the main assembly guide portion 7130R is described. The main assembly guide portion 7130R mainly includes a guide rib 7130R1a for guiding the cartridge B, and cartridge positioning portions 7130R1e and 7130R1f, which pass through the coupling 7150. The rib 7130R1a is provided on the mounting route of the cartridge B. The rib 7130R1a extends to a portion in front of the drive shaft 180 in the mounting direction X4. Further, the height of the ribs 7130R1b near the drive shaft 180 is such that the ribs 7130R1b do not interfere with the coupling 7150 when the coupling 7150 engages the drive shaft 180. The main assembly guide portion 7130R2 mainly includes a guide portion 7130R2a and a cartridge positioning portion 7130R2c, and the guide portion 7130R2a serves to guide a part of the cartridge frame to determine the posture of the cartridge at the time of mounting.

Next, the relationship between the main assembly guide portion 7130R and the cartridge when the cartridge is mounted is described.

As shown in fig. 48(a), the cartridge B moves on the driving side in a state where the intermediate portion (force receiving portion) 7150c contacts the surface of the guide rib (fixing portion, contact portion) 7130R1 a. At this time, the cartridge guide portion 7157a of the support member 7157 is spaced from the guide surface 7130R1c by a distance n 59. For this reason, the self weight of the cartridge B is exerted on the coupling 7150. On the other hand, as described above, the coupling 7150 is disposed such that the downstream side portion of the mounting direction thereof can be inclined upward at the angle α 60 with respect to the mounting direction X4. For this reason, the coupling 7150 is inclined at the driven portion 7150a toward the downstream side with respect to the mounting direction X4 (a direction inclined at an angle α 6 along the driven portion 7150 a) (fig. 49 (a)).

The reason for tilting the coupling 7150 is as follows. The intermediate portion 7150c receives a reaction force of the self weight of the cartridge B from the guide rib 7130R1 a. This reaction force acts on the regulating portions 7157h1 and 7157h2 to regulate the inclination direction. Therefore, the coupling is inclined to a predetermined direction.

When the intermediate portion 7150c moves on the guide rib 7130R1a, a frictional force is generated between the intermediate portion 7150c and the guide rib 7130R1 a. Therefore, the coupling 7150 receives a force in the direction opposite to the mounting direction X4 due to the frictional force. However, the friction force generated by the friction coefficient between the intermediate portion 7150c and the guide rib 7130R1a is smaller than the force that tilts the coupling 7150 toward the downstream side with respect to the mounting direction X5 due to the reaction force. For this reason, by overcoming the frictional force, the coupling 7150 is inclined and moved downward with respect to the mounting direction X4.

Incidentally, the regulating portion 7157g (fig. 46(a1) and 46(b1)) of the support member 7157 may also serve as a regulating means for regulating the inclination. Therefore, the inclination direction of the coupling is regulated by the regulating portions 7157h1 and 7157h2 (fig. 46(a2) and 46(b2)) and the regulating portion 7157g at different positions with respect to the direction of the axis L2. Therefore, the inclination direction of the coupling 7150 can be reliably regulated. Further, the coupling 7150 can always be inclined at an angle α 60. Other ways of regulating the inclination of the coupling 7150 may also be used.

The guide rib 7130R is provided in a space 7150s formed by the driven portion 7150a, the driving portion 7150b, and the intermediate portion 7150 c. Therefore, during the mounting, the longitudinal position (direction relative to the axis L2) of the coupling 7150 in the apparatus main assembly a is regulated (fig. 48(a) and 48 (b)). By regulating the longitudinal position of the coupling 7150, the coupling 7150 can reliably engage the drive shaft 180.

Next, an engaging operation of the coupling 7150 with the drive shaft 180 is described. The joining operation is substantially the same as in embodiment 1 (fig. 19). In this embodiment, the relationship between the main assembly guide portion 7130R2 and the supporting member 7157 and the coupling 7150 during the engagement of the coupling 7150 with the drive shaft 180 is described with reference to fig. 50(a) to 50 (f). In the process in which the intermediate portion 7150c contacts the rib 7130R1a, the cartridge guide portion 7157a is in a state of being separated from the guide surface 7130R1 c. Therefore, the coupling 7150 is inclined (angular position between engagement) (fig. 50(a) and 50 (d)). Then, when the end 7150a1 of the inclined coupler 7150 passes the shaft end 180b3, the middle portion 7150c does not contact the guide rib 7130R1a (fig. 50(b) and 50 (e)). In this case, the cartridge guide portion 7157a passes through the guide surface 7130R1c and the inclined surface 7130R1d, and is in a state where the cartridge guide portion 7157a starts to contact the positioning surface 7130R1e (fig. 50(b) and 50 (e)). Thereafter, the receiving surface 7150f or the protrusion 7150d contacts the end 180b or the pin 182. Then, with the mounting operation of the cartridge, the axis L2 and the axis L1 are close to the same straight line, and the center position of the developing shaft and the center position of the coupling are close to the coaxial straight line. Then, finally as shown in fig. 50(c) and 50(f), axis L1 and axis L2 are substantially in line with each other. Therefore, the coupling 7150 is in the rotational standby state (rotational force transmitting angular position).

In the process of removing the cartridge B from the apparatus main assembly a, the steps thereof are substantially reversed from those of the engaging operation. Specifically, the cartridge B is moved in the detaching direction. Thus, the end 180b pushes the receiving surface 7150 f. As a result, the axis L2 begins to tilt relative to the axis L1. By the cartridge removing operation, the upstream-side end portion 7150a1 is moved in the removing direction X6 along the surface of the end portion 180b so that the axis L2 is inclined until the end portion a1 contacts the shaft end portion 180b 3. In this state, the coupling 7150 passes completely through the shaft end portion 180b3 (fig. 50 (b)). Thereafter, the coupler 7150 contacts the surface of the rib 7130R1a at the middle portion 7150 c. As a result, the coupling 7150 is detached in a state where the coupling 7150 is inclined toward the downstream side with respect to the mounting direction X4. That is, the coupling 7150 is inclined (swung) from the rotational force transmitting angular position to the detaching angular position.

As described above, by the mounting operation of the cartridge to the main assembly by the user, the coupling is swung into engagement with the main assembly drive shaft. Furthermore, a means for maintaining the attitude of the coupling is not particularly required. However, as shown in fig. 4, this structure of previously maintaining the posture of the coupling may also be implemented in combination with the structure of the present embodiment.

In this embodiment, the coupling is inclined in the mounting direction X4 by applying a self-weight to the guide rib. However, the elastic force of a spring or the like may be utilized in addition to the self weight.

In this embodiment, the middle portion of the coupler receives a force to tilt the coupler. However, the present invention is not limited thereto. For example, it is also possible to cause a portion other than the intermediate portion to come into contact with a contact portion of the main assembly when the coupling is inclined by receiving a force from the contact portion.

Further, this embodiment can also be combined with any one of embodiments 2 to 4. In this case, the engagement and disengagement of the coupling with the drive shaft can be further reliably achieved.

(example 6)

Example 6 is described with reference to fig. 51 to 55. In the above-described embodiment, the surface of the developing roller 6110 maintains a predetermined interval with respect to the photosensitive drum 107. In this state, the developing roller 6110 develops the latent image formed on the photosensitive drum 107. In the above-described embodiments, the cartridge using the non-contact type developing system is described. In this embodiment, in a cartridge employing a so-called contact development system, development is performed in a state where the surface of the developing roller is in contact with a latent image formed on the photosensitive drum. That is, a case where the embodiment of the present invention is applied to a cartridge employing a contact developing system will be described.

Fig. 51 is a sectional view of the developing cartridge of this embodiment. Fig. 52 is a perspective view showing the developing device side of the cartridge. Fig. 53 is a cross-sectional view of the cartridge taken along line S24-S24 in fig. 52. Fig. 54(a) and 54(b) are sectional views showing a state in which the developing cartridge is capable of developing and a state in which the developing cartridge is incapable of developing, respectively. Fig. 55(a) and 55(b) are longitudinal sectional views showing the drive connection in the state of fig. 54(a) and 54(b), respectively. The state in which development is not possible refers to a state in which the developing roller 6110 is separated from the photosensitive drum 107.

First, the structure of the developing cartridge B6 employing the contact developing system will be described with reference to fig. 51 and 52.

The cartridge B6 includes a developing roller 6110. During the developing action, the developing roller 6110 is rotated by receiving a rotational force from the apparatus main assembly a by a coupling mechanism described later.

The developer t is accommodated in a developer accommodating frame (developer accommodating portion) 6114. The developer is conveyed to the developing chamber 6113a by the rotation of the agitating member 6116. The conveyed developer is supplied onto the surface of the developing roller 6110 by the rotation of the sponge-like developer supply roller 6115 in the developing chamber 6113 a. Then, the developer is charged by friction between the thin plate-like developing blade 6112 and the developing roller 6110 to form a thin layer. The developer forming the thin layer is conveyed to the developing position by rotation. Next, a predetermined developing bias is applied to the developing roller 6110. Thus, in a state where the surface of the developing roller 6110 contacts the surface of the photosensitive drum 107, the developing roller 6110 develops the electrostatic latent image formed on the photosensitive drum 107. That is, the electrostatic latent image is developed by the developing roller 6110.

The developer not used for the development of the electrostatic latent image (i.e., the developer t remaining on the surface of the developing roller 6110) is removed by the developing roller supply roller 6115. At the same time, new developer t is supplied onto the surface of the developing roller 6110 by the supply roller 6115. Thus, the developing operation is continuously performed.

The cartridge B6 includes a developing unit 6119. The developing unit 6119 includes a developing device frame 6113 and a developer accommodating frame 6114. Further, the developing unit 6119 includes a developing roller 6110, a developing blade 6112, a developer supply roller 6115, a developing chamber 6113a, a developer accommodating frame 6114, and an agitating member 6116.

The developing roller 6110 rotates about the axis L1.

The structure of the apparatus main assembly a is substantially the same as that in embodiment 1, and therefore the description is omitted. However, as for the apparatus main assembly a applied to embodiment 6, in addition to the structure of the above-described main assembly a, a lever (force applying member shown in fig. 54(a) and 54(b)) 300 for bringing the surface of the photosensitive drum 107 and the surface of the developing roller 6110 into contact and separation is provided. Incidentally, the lever 300 will be described later. The user mounts the developing cartridge B described in embodiment 1 to the mounting portion 130a (fig. 3) by guiding the cartridge guides 6140L1, 6140R2, etc. into the apparatus main assembly a. Incidentally, similarly to the above-described cartridge, the cartridge B6 is also mounted to the mounting portion 130a by being moved in a direction substantially perpendicular to the axial direction of the drive shaft 180. Further, the cartridge B6 can be detached from the mounting portion 130 a.

Incidentally, when the cartridge B6 is mounted on the mounting portion 130a as described above, the guide portion (projection) 6140R1 of the cartridge B6 receives a pressing force applied by the elastic force of the urging spring (elastic member) 188R as shown in fig. 15 and 16. Further, due to the elastic force of the urging spring 188L, the guide portion (tenon) 6140L (fig. 52) of the cartridge B6 receives the applied pressure. Thus, the cartridge B6 is held by the apparatus main assembly a and is rotatable about the guides 6140R1 and 6140L 1. That is, the guide portion 6140R1 is rotatably supported by the main assembly guide portion 130R1, and the guide portion 6140L1 is rotatably supported by the main assembly guide portion 130L 1. Then, when the door 109 (fig. 3) is closed, the pushing portion 6114a (fig. 51 and 52) of the cartridge B6 receives an applied pressure due to the elastic force of the pushing spring 192R provided on the door 109 (and the pushing spring 192L on the non-driving side shown in fig. 16). Therefore, the cartridge B6 receives a rotational moment about the guide 6140. Next, nip width regulating members (interval regulating members) 6136 and 6137 (fig. 52) disposed on the end of the developing roller 6110 of the cartridge B6 contact the end of the photosensitive drum 107. For this reason, the developing roller 6110 and the photosensitive drum 107 maintain a constant contact nip. That is, the developing roller 6110 includes a developing shaft 6151 and a rubber portion (elastic member) 6110a (fig. 52 and 53). The developing roller 6110 contacts the photosensitive drum 107 in a state where the rubber portion 6110a is bent. In this state, the developing roller develops the electrostatic latent image formed on the photosensitive drum 107 with toner t.

Next, with reference to fig. 52 and 53, a structure of the developing roller 6110 and a mounting structure (supporting structure) of the coupling 6150 are described.

The developing shaft 6151 is an elongated member composed of a conductive material such as iron or the like. The developing shaft 6151 is rotatably supported by the developing device frame 6113 via a shaft supporting member 6152. Further, the developing gear 6150b is fixedly positioned on the developing shaft 6151 in a non-rotatable manner. The coupling 6150 is tiltably mounted on the developing gear 6150b, the same structure as described in embodiment 1. That is, the coupling 6150 is mounted such that the axis L2 can tilt relative to the axis L1. The rotational force received by the coupling 6150 from the apparatus main assembly a is transmitted to the developing roller 6110 through the drive transmitting pin (rotational force transmitting portion) 6155, the developing gear 6153 and the developing shaft 6151. Thus, the developing roller 6110 rotates.

The rubber portion 6110a is coated on the developing shaft 6151 so as to be coaxial with the developing shaft 6151. The outer peripheral surface of the rubber portion 6110a carries developer (toner) t, and a bias is applied to the developing shaft 6151. Thus, the rubber portion 6110a develops the electrostatic latent image with the developer t carried thereon.

The regulating members 6136 and 6137 are members for making the nip width pipe to a constant level when the surface of the developing roller 6110 contacts the surface of the photosensitive drum 107. That is, the regulating members 6136 and 6137 regulate the amount of pressing down of the surface of the developing roller 6110.

In the contact type developing system in this embodiment, when the state where the developing roller 6110 contacts the photosensitive drum 107 is maintained all the time, the rubber portion 6110a of the developing roller 6110 may be deformed. For this reason, during non-development, it is preferable that the developing roller 6110 be moved away from the photosensitive drum 107. That is, as shown in fig. 54(a) and 54(b), it is preferable that a state in which the developing roller 6110 contacts the photosensitive drum 107 (fig. 54(a)) and a state in which the developing roller 6110 is moved away from the photosensitive drum 107 (fig. 54(b)) are formed.

In a state where the cartridge B6 is mounted on the mounting portion 130a, an upper surface (force receiving portion) 6114a of the developer accommodating frame 6114 of the cartridge B6 is urged by elastic forces of the springs 192R and 192L. In this way, the cartridge B6 rotates (in the clockwise direction X67 in fig. 54(a)) about the guides (support points) 6140R and 6140L of the cartridge B6. Thus, the surface of the developing roller 6110 contacts the surface of the photosensitive drum 107 (the state shown in fig. 54 (a)).

Then, in this embodiment, the lever (urging member, force applying member) 300 provided to the apparatus main assembly a is rotated (i.e., rotated in the counterclockwise direction (the direction indicated by the arrow X45 in fig. 54(b)) by the force of the motor (not shown) rotated by the developing device separation signal. Then, the lever 300 pushes the bottom (force receiving portion) 6114a of the cartridge B6 (developer accommodating frame 6114). Therefore, the cartridge B6 rotates about the guide 6140 (i.e., rotates in the counterclockwise direction X47) against the elastic force action of the springs 192R and 192L. Therefore, the surface of the developing roller 6110 is in a state of being separated from the surface of the photosensitive drum 107 (the state shown in fig. 54 (b)). That is, the cartridge B6 rotates about the guides (bearing points) 6140R and 6140L to move in the direction X66.

The lever 300 is rotated (i.e., rotated in a clockwise direction (the direction indicated by the arrow X44 shown in fig. 54(b)) to the standby position by the force of a motor (not shown) rotated in the opposite direction by the developing device contact signal. Then, the cartridge B6 is returned to the developing device contact portion by the elastic force of the springs 192R and 192L (the state shown in fig. 54 (a)). That is, the cartridge B6 rotates about the guides (bearing points) 6140R and 6140L to move in the direction X46.

Here, the standby position of the lever 300 refers to a state (position) in which the lever 300 is separated from the cartridge B6 (the position shown in fig. 54 (a)).

According to this embodiment, although the developing roller 6110 is still rotating, the cartridge B6 can be moved from the state of fig. 54(B) to the state of fig. 54(a) and from the state of fig. 54(a) to the state of fig. 54 (B).

This operation is described below. Preferably, the rotation of the developing roller 6110 may be started immediately before the state of the cartridge B6 is changed from the state of fig. 54(B) to the state of fig. 54 (a). That is, the developing roller 6110 preferably contacts the photosensitive drum 107 while rotating. In this way, the developing roller 6110 is brought into contact with the photosensitive drum 107 while the developing roller 6110 is rotated, and the photosensitive drum 107 and the developing roller 6110 may be damaged. The same is true when the developing roller 6110 is moved away from the photosensitive drum 107, and therefore, it is preferable to separate the developing roller 6110 from the photosensitive drum 107.

Referring to fig. 55(a) and 55(b), an example of the driving input structure in this embodiment is described.

The state of fig. 55(a) corresponds to the state of fig. 54(a), i.e., the state in which the developing roller 6110 contacts the photosensitive drum 107 and is rotatable. That is, the axis L1 of the developing roller 6110 and the axis L2 of the coupling 6150 are substantially collinear, so that the coupling 6150 is in a state capable of receiving the rotational force from the drive shaft 180. When the development is completed, the cartridge B6 is moved from this state in the direction X66 (see fig. 54 (a)). At this time, the developing shaft 6153 is gradually moved in the direction X66 such that the axis L2 is gradually inclined. When the cartridge B6 is in the state of fig. 55(B), the developing roller 6110 is completely moved away from the photosensitive drum 107. After that, the rotation of the motor 186 is stopped. That is, even in the state of fig. 55(b), the motor 186 rotates for a certain time. According to this embodiment, even in the state where the axis L2 is inclined, the cartridge B6 can transmit the rotational force. Therefore, even in the state shown in fig. 55(B), the cartridge B5 can transmit the rotational force to the developing roller 6110. Therefore, according to the present invention, the developing roller 6110 can be moved away from the photosensitive drum 107 despite the rotation of the developing roller 6110.

Similar operations are performed when the state of the cartridge B6 changes from the state of fig. 55(B) to the state of fig. 55 (a). That is, the motor 186 is rotated from the state of fig. 55(b) so that the developing roller 6110 can be rotated. That is, according to this embodiment, the developing roller 6110 can contact the photosensitive drum 107 while rotating.

Incidentally, the engaging operation and the disengaging operation of the coupling 6150 with respect to the drive shaft 180 are the same as those described in embodiment 1, and therefore the description is omitted.

The structure described in example 6 is as follows.

The apparatus main assembly a described in embodiment 6 has a lever (urging member) 300 in addition to the above-described structure of the apparatus main assembly a.

The cartridge B6 in embodiment 6 includes a bottom (force receiving portion) 6114B. In the state where the cartridge B6 is mounted to the apparatus main assembly a, the bottom 6114B receives an urging force for moving the developing roller 6110 away from the photosensitive drum 107.

The cartridge B is urged by the elastic force of the springs 192R and 192L on the upper surface (force receiving portion) 6114a of the developer accommodating frame 6114. Therefore, the developing roller 6110 of the cartridge B6 is pressed against the photosensitive drum 107 rotatably positioned in the apparatus main assembly a. Therefore, the cartridge B6 is set in a contact state where the developing roller 6110 contacts the photosensitive drum 107.

When the upper surface (force receiving portion) 6114a of the cartridge B6 is pushed by the lever 300, the cartridge B6 is disposed in a separated state in which the developing roller 6110 is separated from the photosensitive drum 107.

Since the coupling 6150 is in the rotational force transmitting angular position described above, the cartridge B6 in the contact state or the separated state can transmit the rotational force from the coupling 6150 to the developing roller 6110. When the cartridge B6 is dismounted from the apparatus main assembly a in the direction substantially perpendicular to the axis L1, the coupling 6150 is moved from the above-described rotational force transmitting angular position to the above-described disengaging angular position. Therefore, the coupling 6150 can be separated from the drive shaft 180.

In this way, even when the cartridge B6 is in the above-described separated state and the axis L3 and the axis L1 are deviated from each other, with the coupling 6150 to which the present invention is applied, the rotational force can be smoothly transmitted from the drive shaft 180 to the developing roller 6110.

Incidentally, the axis L1 represents the rotation axis of the developing roller 6110, and the axis L3 represents the rotation axis of the drive shaft 180.

Thus, in embodiment 6, the effects of applying the embodiment of the present invention are effectively utilized.

As described above, even when the drive input position is not at the swing center, the rotational force can be transmitted to the developing roller in the state where the developing cartridge is moved away from the photosensitive drum. For this reason, a certain free range of the drive input position can be allowed, so that the cartridge and the apparatus main assembly can be downsized.

Incidentally, in this embodiment, the driving input position is coaxial with the developing roller. However, as described in the later embodiments, a similar effect can be achieved also in the case where the driving input position is not coaxial with the developing roller.

In this embodiment, the engagement and disengagement of the coupling during the disengagement of the developing device is described. However, in this embodiment, the engagement and disengagement of the coupling can also be applied to embodiment 1. Therefore, in this embodiment, the cartridge can be mounted/dismounted without providing the apparatus main assembly particularly with the drive connection mechanism and the release mechanism. Further, the drive connection and release can be achieved during the contact/separation of the developing roller of the cartridge with respect to the photosensitive drum.

That is, according to the cartridge B6 to which the present embodiment is applied, the cartridge B6 can be mounted to and dismounted from the apparatus main assembly a by being moved in the direction substantially perpendicular to the axis L3 of the drive shaft 180. Further, according to the cartridge B6, even during the separation of the developing device, the rotational force can be smoothly transmitted from the apparatus main assembly a to the developing roller 6110.

Here, "during separation of the developing device" means that the photosensitive drum 107 and the developing roller 6110, the surfaces of which have contacted each other, are separated (moved away) from each other.

The description of fig. 6 is an example of taking a so-called developing cartridge as a cartridge, but the present invention can also be applied to a so-called process cartridge as a cartridge.

The structure of the cartridge is not limited to that in embodiment 6, and may be changed to another structure as appropriate.

Embodiment 6 can also be applied to other embodiments.

(example 7)

Embodiment 7 is described with reference to fig. 56 and 57.

Embodiment 7 differs from embodiment 6 in the drive input position (coupling position) and structure for transmitting the rotational force from the coupling to the developing roller and the developer supply roller. Specifically, the coupling 8150 is not located on the axis L1 of the developing roller 8110, but is located at a position deviated from the axis L1.

Fig. 56 is a perspective view of the cartridge B8. Fig. 57 is a perspective view showing a driving portion of the cartridge B8.

The developing roller gear 8145 and the developer supply roller gear 8146 are arranged at a drive-side end portion of the developing roller 8110 and a drive-side end portion of the developer supply roller 6115 (fig. 51), respectively. Gears 8145 and 8146 are each secured to a shaft (not shown). These gears transmit the rotational force received from the apparatus main assembly a through the coupling 8150 to the other rotatable members (the developing roller 8110, the developer supplying roller 6115, the toner agitating member (not shown), etc.) of the cartridge B8.

Next, the drive input gear 8147 to which the coupling 8150 is mounted (by which the coupling 8150 is supported) will be described.

As shown in fig. 57, the gear 8147 is rotatably fixed at a position where the gear 8147 engages with the developing roller gear 8145 and the developer supply roller gear 8146. The gear 8147 includes a coupling accommodating portion 8147j similar to that in the developing roller gear 151 described in embodiment 1. The coupler 8150 is tiltably mounted to the gear 8147 by a retaining member 8156. That is, the coupling 8150 is not provided on the axis L1 of the developing roller 8110, but is provided at a position deviated from the axis L1. The rotational force received from the drive shaft 180 through the coupling 8150 is transmitted to the developing roller 8110 through the gears 8147 and 8145. The rotational force is further transmitted to the developer supply roller 6115 through the gears 8147 and 8146.

The support member 8157 has a bore defining an inner peripheral surface 8157i engageable with the gear 8147. The description of the engagement, drive, and disengagement of the coupling by the mounting and dismounting operations of the cartridge is the same as that in embodiment 1, and therefore the description is omitted.

Further, as a structure in which the axis L2 of the coupling 8150 is inclined to the pre-engagement angular position immediately before the coupling 8150 engages the drive shaft, any one of embodiments 2 to 5 may be employed.

As described above, the coupling 8150 need not be disposed at the end coaxial with the developing roller 8110. According to this embodiment, the design freedom range of the image forming apparatus main assembly and the cartridge can be improved.

(example 8)

Embodiment 8 is described with reference to fig. 58 to 62.

Fig. 58 is a front sectional view of the process cartridge B9 of this embodiment, and fig. 59 is a perspective view of the process cartridge B9. Fig. 60 is a main sectional view of the apparatus main assembly, and fig. 61 is a perspective view showing a mounting guide (driving side) and a driving connecting portion of the apparatus main assembly. Fig. 62(a) to 62(c) are schematic views showing a process of mounting the process cartridge into the apparatus main assembly as viewed from above the apparatus. The process cartridge is an example of the above-described cartridge.

In this embodiment, the present invention is applicable to a process cartridge which is made by integrally supporting a photosensitive drum and a developing roller as a unit and is detachably mountable to the apparatus main assembly. That is, this embodiment relates to a process cartridge which can be mounted to and dismounted from the apparatus main assembly a having a drive shaft by moving the process cartridge in a direction substantially perpendicular to the axial direction of the drive shaft. According to this embodiment, a process cartridge (hereinafter simply referred to as cartridge) includes two portions for receiving a rotational force from the apparatus main assembly.

That is, the cartridge to which the present invention is applied receives the rotational force for rotating the photosensitive drum from the apparatus main assembly and the rotational force for rotating the developing roller from the apparatus main assembly, respectively.

The present invention can also be applied to such a structure, and effects described later can be obtained. The charging roller 9108 in contact with the photosensitive drum 9107 functions as a charging member (process member).

Further, the cartridge B9 includes a developing roller 9110 as a developing member (process member). The developing roller 9110 supplies the developer t to the developing region of the photosensitive drum 9107. The developing roller 9110 develops an electrostatic latent image formed on the photosensitive drum 9107 by using the developer t. The developing roller 9110 includes a magnetic roller (fixed magnet) 9111.

A developing blade 9112 is provided in contact with the developing roller 9110. This developing blade 9112 determines the amount of developer t to be deposited on the outer peripheral surface of the developing roller 9110.

The developer accommodated in the developer accommodating chamber 9114 is fed by rotation of the agitating members 9115 and 9116. Then, a developer layer charged by the developing blade 9112 is formed on the surface of the developing roller 9110. Next, the developer t is transferred onto the photosensitive drum 9107 according to the latent image. Thus, the latent image is developed.

An elastic cleaning blade 9117a as a cleaning member (process member) is provided in contact with the photosensitive drum 9107. The blade 9117a removes the developer t remaining on the photosensitive drum 9107 after the developer image is transferred onto the recording material 9102. The developer t removed from the surface of the photosensitive drum 9107 by the scraper 9117a is collected in a developer-removing container 9117 b.

The cartridge B9 includes a first frame unit 9119 and a second frame unit 9120 that are swingably (rotatably) connected together.

The first frame unit (developing device) 9119 is constituted by a first frame 9113 as a part of a cartridge frame. The first frame unit 9119 includes a developing roller 9110, a developing blade 9112, a developing chamber 9113a, a developer accommodating chamber (developer accommodating portion) 9114, and agitating members 9115 and 9116.

The second frame unit 9120 is constituted by a second frame 9118 as a part of a cartridge frame. The second frame unit 9120 includes a photosensitive drum 9107, a cleaning blade 9117a, a developer removing container (developer removing accommodating portion) 9117b, and a charging roller 9108.

The first frame unit (developing device) 9119 and the second frame unit 9120 are rotatably connected by a pin P. The developing roller 9110 is pressed against the photosensitive drum 9107 by an elastic member (not shown) provided between the units 9119 and 9120. That is, the first frame unit (developing device) 9119 determines the position of the second frame unit 9120.

The user grasps the handle T and mounts the cartridge B9 to the cartridge mounting portion 9130a provided to the apparatus main assembly a 9. At this time, as described later, during the mounting operation of the cartridge B9, the drive shaft 9108 provided in the apparatus main assembly a9 and the cartridge-side developing roller coupling (rotational force transmitting portion) 9150 of the cartridge B9 are connected to each other. The developing roller 9110 or the like is rotated by receiving a rotational force from the apparatus main assembly a 9.

After the cartridge B9 was mounted to the apparatus main assembly a9, the door 109 was closed. With the closing operation of the door 109, the main assembly-side drum coupling 9190 and the cartridge-side drum coupling (rotational force transmitting portion) 9145 are connected to each other. Thus, by receiving the rotational force from the apparatus main assembly a9, the photosensitive drum 9107 rotates. The main assembly-side drum coupling 9190 is a non-circular twisted hole having a plurality of corners in cross section. The coupling 9190 is provided at a central portion of the rotatable drive member 9191. A gear (helical gear) 9191a is provided at an outer circumferential surface of the rotatable driving member 9191. The rotational force from the motor 196 is transmitted to the gear 9191 a.

Further, the cartridge-side drum coupler 9145 is a non-circular twisted protrusion having a plurality of corners in cross section. Coupling 9145 engages coupling 9190 to receive rotational force from motor 186. That is, in a state where the hole of the coupling 9145 and the protrusion of the coupling 9190 are engaged with each other, the rotatable member 9191 rotates. Therefore, in a state where the projection is subjected to a tensile force in the entry hole, the rotational force of the rotatable driving member 9191 is transmitted to the photosensitive drum 9107 through the projection.

The shape of the projection may be appropriately changed as long as the projection can receive the rotational force from the hole in the state of being engaged with the hole. In this embodiment, the apertures are substantially in the shape of equilateral triangles and the protrusions are substantially in the shape of twisted equilateral triangular prisms. Therefore, according to the present invention, it is possible to transmit the rotational force from the hole to the protrusion in a state where the axis of the hole and the axis of the protrusion are aligned with each other (center alignment) and the protrusion is subjected to the tensile force into the hole. Therefore, the photosensitive drum 9107 can be rotated accurately and smoothly. Further, the hole is provided coaxially with the axis of the shaft portion 9107a of the photosensitive drum 9107. The shaft portion 9107a is provided at one end portion of the photosensitive drum 9107, and is rotatably supported by the unit 9120.

As described later, the main assembly-side drum coupling 9190 (rotatable driving member 9191) is moved by a moving member (retractable mechanism) 9195 interlocked with the closing operation of the door 109. That is, the coupling 9190 is moved by the moving member 9195 in the direction of the rotation axis X70 of the coupling 9190 and in the direction X93 in which the coupling 9145 is provided. Thus, the coupling 9190 and the coupling 9145 are engaged with each other. Then, the rotational force of the coupling 9190 is transmitted to the coupling 9145 (fig. 62 (b)).

The coupling 9190 (rotatable driving member 9191) is moved in the direction of the rotation axis X70 and in the direction X95 in which the coupling 9190 is separated from the coupling 9145 by the moving member 9195 that is interlocked with the opening operation of the door 109. Thus, the coupling 9190 and the coupling 9145 are separated from each other. (FIG. 62 (c)).

That is, as described later, the coupling 9190 is moved toward and away from the coupling 9145 in the direction of the rotation axis X70 by the moving member (retractable member) 9195 (in the directions indicated by arrows X93 and X95 in fig. 62(b) and 62 (c)). Incidentally, since a known structure can be appropriately used as the structure of the moving member 9195, a description of the structural details of the moving member 9195 is omitted. The structures of the coupling 9145, the coupling 9190, and the moving member 9195 are described in, for example, japanese patent No. 2875203.

As shown in fig. 61, the mounting member 9130 in this embodiment includes main assembly guide portions 9130R1 and 9130R2 provided in the apparatus main assembly a 9.

These guide portions are oppositely provided in a cartridge mounting portion 9130a (cartridge mounting space) provided in the apparatus main assembly a 9. Fig. 61 shows a driving side surface, and a non-driving side has a shape symmetrical to the driving side, and thus description is omitted. The guide portions 9130R1 and 9130R2 are provided in the mounting direction of the cartridge B9.

When the cartridge B9 is mounted to the apparatus main assembly a9, a cartridge guide portion described later is inserted while being guided by the guide portions 9130R1 and 9130R 2. The cartridge B9 is mounted to the apparatus main assembly a9 in a state where the door 109 is opened about the shaft 9109a with respect to the apparatus main assembly a 9. By closing the door 109, the mounting of the cartridge B9 to the apparatus main assembly a9 is completed. Incidentally, when the cartridge B9 is detached from the apparatus main assembly a9, the detaching operation is also performed in a state where the door 109 is opened. These operations are performed by the user.

In this embodiment, as shown in fig. 59, the outer-end peripheral portion 9159a of the shaft support member 9195 also serves as a cartridge guide portion 9140R 1. That is, the shaft supporting member 9159 protrudes outward so that its outer circumferential surface has a guiding function.

At a longitudinal end portion (driving side) of the second frame unit 9120, the cartridge guide portion 9140R2 is disposed above the cartridge guide portion 9140R 1.

When the cartridge B9 is mounted to the apparatus main assembly a9 and the cartridge B9 is dismounted from the apparatus main assembly a9, the guide portion 9140R1 is guided by the guide portion 9130R1, and the guide portion 9140R2 is guided by the guide portion 9130R 2.

The guide structure of the apparatus main assembly other end side and the guide structure of the cartridge other end side are the same as those described above, and therefore the description is omitted here. In the above-described direction, the cartridge B9 is moved in the direction substantially perpendicular to the direction of the axis L3 of the drive shaft 9180 to be mounted to and dismounted from the apparatus main assembly a9 and 9.

When this cartridge B9 is mounted to the apparatus main assembly a9, the coupling 9150 engages the drive shaft 9180 of the apparatus main assembly a9, similarly to the above-described embodiment. Then, by the rotation motor 186, the drive shaft 9180 is rotated. The developing roller 9110 rotates by a rotational force transmitted to the developing roller 9110 by the coupling 9150. Incidentally, as for the drive transmission path in the cartridge, as described in embodiment 1, the coupling may be arranged coaxially with the developing roller 9110 or at a position deviated from the axis of the developing roller 9110. The engagement and disengagement between the coupling 9150 and the drive shaft 9180 are the same as described above, and therefore, the description is omitted.

As the structure of the cartridge-side developing roller coupler 1950, the structure of the above-described coupler can be suitably adopted.

Here, referring to fig. 62(a) to 62(c), a procedure of mounting the above-described process cartridge B9 to the mounting portion 9130a to establish driving connection between the apparatus main assembly a9 and the cartridge B9 is described.

In fig. 62(a), the cartridge B9 is mounted to the apparatus main assembly a 9. At this time, as described above, the axis L2 of the coupling 9150 is inclined toward the downstream side with respect to the mounting direction (X92). Further, the apparatus main assembly-side drum coupling 9190 to be engaged with the drum coupling 9145 is retracted so as not to obstruct the mounting path of the cartridge B9. In fig. 62(a), the retraction amount is represented by X91. In this figure, the drive shaft 9180 appears to be in the mounting (dismounting) path of the cartridge B9. However, as can be seen from fig. 61, the drum coupling 9145 and the developing roller coupling 9150 are deviated from each other in the cross-sectional direction (vertical direction) with respect to the moving path. Therefore, the drive shaft 1980 does not hinder the mounting and dismounting of the cartridge B9.

Next, from this state, when the user inserts the cartridge B into the apparatus main assembly a9, the cartridge B9 is mounted to the mounting portion 9130 a. Similar to the foregoing description, the coupling 9150 is engaged with the drive shaft 9180 by this operation. Thus, the coupling 9150 is in a state capable of transmitting the rotational force to the developing roller 9110.

Next, the drum coupling 9190 on the apparatus main assembly a9 side is moved in the direction X93 by the moving member 9195 moving in accordance with the closing operation (fig. 61) of the user closing door 109 (fig. 62 (b)). Then, the coupling 9190 engages the drum coupling 9145 of the cartridge B9 to be placed in a rotational force transmittable state. After that, by the image forming operation, the rotational force from the motor 186 is transmitted to the drum gear 9190 fixed to the drum coupling 9190. Further, the rotational force is transmitted to the developing gear 9181 fixed on the drive shaft 9180 for receiving the rotational force from the coupling 9150. Therefore, the rotational force from the motor 196 is transmitted to the photosensitive drum 9107 through the drum coupling 9190 and the drum gear 9190. Further, the rotational force from the motor 196 is transmitted to the developing roller 9110 through the coupling 9150, the rotational force receiving drive shaft 9180, and the developing gear 9181. Incidentally, the details of the transfer path from the coupling 9150 in the developing unit 9114 to the developing roller 9110 through the supporting member 9147 are the same as those described above, and therefore, the description is omitted. When the cartridge B9 is detached from the apparatus main assembly a9, the user opens the door 109 (fig. 61). The drum coupling 9190 on the apparatus main assembly a9 side is moved in the direction X95 opposite to the direction X93 by the moving member 9195 moving along with the opening operation of the door 109 (fig. 62 (c)). Thus, the coupling 9190 is disengaged from the drum coupling 9145. Thus, the cartridge B9 can be detached from the apparatus main assembly a 9.

As described above, in addition to the above-described structure of the apparatus main assembly a, the apparatus main assembly a9 in embodiment 8 further includes the moving member (retractable mechanism) 9195 for movement of the main assembly-side drum coupling 9190 and the coupling 9145 in their axial direction (rotation axis direction X70).

In embodiment 8, the cartridge (process cartridge) B9 integrally includes a photosensitive drum 9107 and a developing roller 9110.

In embodiment 8, when the cartridge B9 is detached from the apparatus main assembly a9 in the direction substantially perpendicular to the axis L1 of the developing roller 9110, the cartridge-side developing roller coupling 9150 is moved as described below. That is, the coupling 9150 is moved from the rotational force transmitting angular position to the disengaging angular position so as to be disengaged from the drive shaft 9180. Then, by the moving member 9185, the main assembly-side drum coupling 9190 is moved in the axial direction thereof and in the direction in which the coupling 9190 is separated from the cartridge-side drum coupling 9145. Thus, the cartridge-side drum coupling 9145 is separated from the main assembly-side drum coupling 9190.

According to embodiment 8, as for the coupling structure for transmitting the rotational force from the apparatus main assembly a9 to the photosensitive drum 9107 and the coupling structure for transmitting the rotational force from the apparatus main assembly a9 to the developing roller 9110, the number of moving members can be reduced as compared with those in which one moving member is required for each structure.

Therefore, according to embodiment 8, the apparatus main assembly can be downsized. Further, in designing the apparatus main assembly, an increased design freedom range can be allowed.

Further, this embodiment can also be applied to the case of the contact developing system as described in embodiment 6. In this case, the present embodiment is applicable not only to the mounting and dismounting of the cartridge but also to the drive connection at the time of separation of the developing device.

Further, in this embodiment, for the drive connection of the photosensitive drum, such a manner as in this embodiment is not employed, but a coupling as in this embodiment may also be arranged.

As described above, according to this embodiment, by applying the present invention to the case where at least the developing roller is rotated (i.e., the rotational force is transmitted to the developing device), the number of moving members (retractable mechanisms) can be reduced by at least one. Therefore, according to the embodiment, it is possible to reduce the size of the apparatus main assembly and increase the design free range.

Incidentally, in embodiment 8, as a cartridge-side drum coupling for receiving a rotational force from the apparatus main assembly to rotate the photosensitive drum, a twisted projection is described as an example. However, the present invention is not limited thereto. The present invention can be suitably applied to a coupling structure which allows the main assembly-side drum coupling to be movable (retractable) in the rotational direction of the cartridge-side drum coupling. That is, in the present invention, such a coupling structure is such that the main assembly-side drum coupling approaches to, and is engaged with, the cartridge-side drum coupling in the above-described moving direction, and departs from the cartridge-side drum coupling in the above-described moving direction. For applying embodiments of the invention, for example, a so-called pin-drive coupling arrangement may be applied.

According to embodiment 8, in the structure in which the rotational forces for rotating the photosensitive drum and the developing roller are transmitted from the apparatus main assembly, respectively, the number of moving structures for moving (retracting) the coupling relative to the rotational direction thereof can be reduced. That is, as the moving structure, only a structure that transmits the rotational force to the photosensitive drum may be used.

Therefore, according to embodiment 8, as compared with the case where the structure for transmitting the rotational force to the photosensitive drum and the structure for transmitting the rotational force to the developing roller both require the moving structure, the effect of simplifying the apparatus main assembly structure can be achieved.

(example 9)

Example 9 is described with reference to fig. 63.

In embodiment 9, the present invention is applied to both the coupling which receives a rotational force from the apparatus main assembly to rotate the photosensitive drum and the coupling which receives a rotational force from the apparatus main assembly to rotate the developing roller.

That is, the cartridge B10 to which the present invention is applied differs from the cartridge B9 described in embodiment 8 in that: by using a coupling structure similar to that of embodiment 8, the photosensitive drum 9107 also receives a rotational force from the apparatus main assembly.

According to embodiment 9, without using the moving member (retractable mechanism) described in embodiment 8, the process cartridge B10 can be moved in the direction substantially perpendicular to the direction of the axis L3 of the drive shaft 180 to be mounted to and dismounted from the apparatus main assembly.

The cartridge B10 in embodiment 9 is different from the cartridge B9 in embodiment 8 only in the cartridge-side drum coupling structure and the structure for transmitting the rotational force received by the coupling to the photosensitive drum, and the other structures are the same.

Further, as for the structure of the apparatus main assembly side, the two cartridges are different only in the drum coupling structure of the main assembly side.

The apparatus main assembly to which embodiment 9 is applied includes the drive shaft described in the foregoing embodiment in place of the main assembly-side drum coupling structure in embodiment 8, and therefore the description thereof is omitted. With the apparatus main assembly of the present embodiment (embodiment 9), there are provided a drive shaft (first drive shaft) 180 and a drive shaft (second drive shaft) (not shown) having the same structure as the drive shaft 180. However, similarly as in embodiment 8, the moving paths of the cartridge-side drum coupling 10150 and the cartridge-side developing roller coupling 9150 deviate from each other in the cross-sectional direction (vertical direction). Therefore, the first drive shaft 180 and the second drive shaft (not shown) do not hinder the attachment and detachment of the cartridge B10.

The cartridge-side drum coupling 10150 of the cartridge B10 has the same structure as the above-described embodiment, similarly to the case of the cartridge-side developing roller coupling 9150, and therefore the description will be made with reference to the above-described coupling structure.

According to embodiment 9, the cartridge B10 is moved in the direction substantially perpendicular to the direction of the axis L3 of the first drive shaft 180 and the second drive shaft (not shown) to be mounted to and dismounted from the apparatus main assembly.

Further, in embodiment 9, when the cartridge B10 is mounted on the cartridge mounting portion 130a, the first drive shaft 180 and the developing roller coupling 9150 are engaged with each other, so that the rotational force is transmitted from the drive shaft 180 to the coupling 9150. The developing roller 9110 rotates by the rotational force received by the coupling 9150.

Further, the second drive shaft and the drum coupling 10150 are engaged with each other, so that the rotational force is transmitted from the second drive shaft to the coupling 10150. The photosensitive drum 9107 rotates by the rotational force received by the coupling 10150.

With embodiment 9, the structure described in the above embodiments can be suitably applied.

According to this embodiment, without using the moving member (retractable mechanism) described in embodiment 8, by moving the process cartridge B10 in the direction substantially perpendicular to the direction of the drive shaft axis, it can be mounted to and dismounted from the apparatus main assembly.

Therefore, the structure of the apparatus main assembly can be simplified.

In the above-described embodiment, the apparatus main assembly includes the drive shaft (180, 1180, 9180) having the rotational force transmitting pin (rotational force applying portion) 182. Further, the cartridges (B, B2, B6, B8, B9, B10) are moved in a direction substantially perpendicular to the direction of the axis L3 of the drive shaft so as to be mounted to and dismounted from the apparatus main assembly (A, A2, a 9). Each of the cartridges described above includes a developing roller (110, 6110, 8110, 9110) and a coupler (150, 1150, 4150, 6150, 7150, 8150, 9150, 10150, 12150, 14150).

i) The developing roller (110, 6110, 8110, 9110) is rotatable about its axis L1 and develops an electrostatic latent image formed on the photosensitive drum (107, 9107).

ii) the coupling engages a rotational force transmitting pin (rotational force applying portion) (182, 1182, 9182) to receive a rotational force rotating the developing roller from the pin. The coupling may be one of couplings 150, 1150, 4150, 6150, 7150, 8150, 9150, 10150, 12150, 14150. The coupling may be at a rotational force transmitting angular position for transmitting the rotational force of the rotating developing roller to the developing roller. The coupling may be in a pre-engagement angular position inclined in a direction away from the developing roller axis L1 from the rotational force transmitting angular position and a disengaging angular position inclined from the rotational force transmitting angular position. When the cartridges (B, b-2, b6, b8, b9, b10) are mounted to the main assembly in the direction substantially perpendicular to the developing roller axis L1, the coupling is moved from the pre-engagement angular position to the rotational force transmitting angular position. Thus, the coupling is opposed to the drive shaft. When the cartridge is dismounted from the main assembly in the direction substantially perpendicular to the developing roller axis L1, the coupling is moved from the rotational force transmitting angular position to the disengaging angular position. In this way, the coupling is separated from the drive shaft.

In a state where the cartridge is set in the main assembly, a part of the coupling is located behind the drive shaft as viewed from a direction opposite to the taking-out direction X6 (e.g., fig. 19 (d)). One part of the coupling is one of the free end positions 150a1, 1150a1, 4150a1, 12150a1, 14150 A3. The taking-out direction X6 is a direction in which the cartridge is detached from the main assembly. When the cartridge B is detached from the main assembly a, the coupling performs the following actions as the cartridge moves in a direction substantially perpendicular to the axis L1 of the developing roller 110. The coupling is moved (inclined) from the rotational force transmitting angular position to the disengaging angular position so that the portion of the coupling bypasses the drive shaft.

When the cartridge is mounted to the main assembly, the coupling performs the following actions. The coupling is moved (inclined) from the pre-engagement angular position to the rotational force transmitting angular position such that the portion of the coupling on the downstream side with respect to the mounting direction X4 bypasses the drive shaft. The mounting direction X4 is a direction in which the cartridge is mounted to the main assembly.

In the state where the cartridge is mounted to the main assembly, the portion or member of the coupling is located behind the drive shaft as viewed from the direction opposite to the taking-out direction X6 in which the cartridge is dismounted from the main assembly. When the coupling is detached from the main assembly, the coupling performs the following actions. When the cartridge is moved in the direction substantially perpendicular to the axis L1 of the developing roller, the coupling is moved (inclined) from the rotational force transmitting angular position to the disengaging angular position so that the portion of the coupling bypasses the drive shaft.

In the above embodiments, the coupler has a recess (150z, 1150z, 1350z, 4150z, 6150z, 7150z, 9150z, 12150z, 14150z) coaxial with the coupler rotational axis L2. The recess covers the free end of the drive shaft 180 in the state where the coupling is in the rotational force transmitting angular position. The rotational force receiving surface (rotational force receiving portion) engages a rotational force transmitting pin (rotational force applying portion) (182, 1182, 9182) projecting at the free end portion of the drive shaft in a direction perpendicular to the drive shaft axis L3 in the rotational direction of the coupling. The rotational force receiving surface is one of the rotational force receiving surfaces 150e, 1150e, 1350e, 4150e, 6150e, 7150e, 9150e, 12150e, 14150 e. Thus, the coupling receives a rotational force from the drive shaft to rotate. When the cartridge is dismounted from the main assembly, the coupling performs the following actions. When the cartridge is moved in the direction substantially perpendicular to the axis L1 of the developing roller, the coupling is pivoted (inclined) from the rotational force transmitting angular position to the separating angular position, so that the portion of the recess bypasses the drive shaft. In this way, the coupling can be decoupled from the drive shaft. The portion is one of free ends 150a1, 1150a1, 4150a1, 12150a1, 14150 A3.

As described hereinabove, the coupler has a recess coaxial with its rotational axis L2. The recess covers the free end of the drive shaft in a state where the coupling is in the rotational force transmitting angular position. The rotational force receiving surface (rotational force receiving portion) engages the rotational force transmitting pin of the free end portion of the drive shaft in the rotational direction of the coupling. Thus, the coupling receives a rotational force from the drive shaft to rotate. When the cartridge is dismounted from the main assembly, the coupling performs the following actions. When the cartridge is moved in the direction substantially perpendicular to the axis L1 of the developing roller, the coupling is pivoted (moved) from the rotational force transmitting angular position to the disengaging angular position so that the portion of the recess bypasses the drive shaft. In this way, the coupling can be decoupled from the drive shaft.

The rotational force receiving surfaces (rotational force receiving portions) are provided such that they are positioned on a virtual circle C1 having a center S on the rotational axis L2 of the coupling (e.g., fig. 6 (d)). In this embodiment, four rotational force receiving surfaces are provided. Thus, according to the embodiment, the coupling can uniformly receive the force from the main assembly. Therefore, the coupling can be smoothly rotated.

In the state where the coupling is in the rotational force transmitting angular position, the axis L2 of the coupling is substantially coaxial with the axis L1 of the developing roller. In the state where the coupling is in the disengaged angular position, the coupling is inclined with respect to the axis L1 so that the upstream side thereof can sweep the free end of the drive shaft in the take-out direction X6. The upstream side is one of the free end positions 150a1, 1150a1, 4150a1, 12150a1, 14150 A3.

The above-described cartridge is a developing cartridge that does not include a photosensitive drum. Alternatively, the cartridge is a process cartridge including a photosensitive drum as one unit. By applying the present invention to these cartridges, the effects as described above are provided.

(other embodiments)

In the above-described embodiment, the cartridge is mounted or dismounted downward or upward at an angle with respect to the driving shaft of the main assembly. However, the present invention is not limited to this structure. The present invention can be suitably applied to a cartridge that can be attached and detached in a direction perpendicular to the axis of the drive shaft.

In the foregoing embodiment, the mounting path is straight with respect to the main assembly, but the present invention is not limited to this structure. The present invention can also be suitably applied to a case where the installation path includes a path provided in a combination of straight or curved paths.

The developing cartridge of each embodiment forms a monochrome image. However, the present invention can also be suitably applied to a cartridge having a plurality of developing members to form a color image (a two-color image, a three-color image, or a four-color image).

The process cartridge of each embodiment forms a monochrome image. However, the present invention can also be suitably applied to a cartridge that includes a plurality of photosensitive drums, a developing member, and a charging member to form a color image such as a two-color image, a three-color image, or a four-color image, respectively.

The developing cartridge includes at least a developing roller (developing member).

The process cartridge includes, as a unit, an electrophotographic photosensitive member and a process member which is actable on the electrophotographic photosensitive member and is detachably mountable to the main assembly of the electrophotographic image forming apparatus. For example, the process cartridge includes at least an electrophotographic photosensitive member and a developing part as a process part.

The cartridges (developing cartridge and process cartridge) are detachably mountable to the main assembly by a user. In view of this, the user can efficiently perform maintenance on the main assembly.

According to the foregoing embodiment, the coupling can be mounted and dismounted with respect to the main assembly, which is not provided with the mechanism for moving the main assembly-side coupling member for transmitting the rotational force in the axial direction thereof, in the direction substantially perpendicular to the drive shaft axis. The developing roller can be smoothly rotated.

According to the above-described embodiment, the cartridge can be detached from the main assembly of the electrophotographic image forming apparatus, which has the driving shaft, in the direction substantially perpendicular to the axis of the driving shaft.

According to the above-described embodiment, the cartridge can be mounted to the main assembly of the electrophotographic image forming apparatus, which has the driving shaft, in the direction substantially perpendicular to the axis of the driving shaft.

According to the above-described embodiment, the developing cartridge can be mounted to and dismounted from the main assembly of the electrophotographic image forming apparatus, which has the driving shaft, in the direction substantially perpendicular to the driving shaft axis with respect to the main assembly of the electrophotographic image forming apparatus.

According to the above-described embodiments, it is possible to move the developing cartridge in the direction substantially perpendicular to the axis of the driving shaft to mount and dismount it to and from the main assembly even if the driving motor (driving gear) provided in the main assembly is not moved in the direction of the axis thereof.

According to the above-described embodiment, the developing roller can be rotated smoothly as compared with the case where gear-gear engagement is employed between the main assembly and the cartridge.

According to the above-described embodiment, the removal of the cartridge in the direction substantially perpendicular to the axis of the drive shaft provided in the main assembly and the smooth rotation of the developing roller can be performed simultaneously.

According to the above-described embodiment, mounting the cartridge in the direction substantially perpendicular to the axis of the drive shaft provided in the main assembly and smoothly rotating the developing roller can be performed simultaneously.

According to the above-described embodiment, mounting and dismounting of the cartridge in the direction substantially perpendicular to the axis of the drive shaft provided in the main assembly and smooth rotation of the developing roller can be performed simultaneously.

According to the above-described embodiments, in the developing cartridge (or the developing device of the process cartridge) positioned with respect to the photosensitive drum, it is possible to reliably apply drive to the developing roller and achieve smooth rotation.

[ Industrial Applicability ]

As described hereinabove, in the present invention, the axis of the coupling member may be at different angular positions with respect to the axis of the developing roller. With this structure of the invention, the coupling member can engage the drive shaft in the direction substantially perpendicular to the drive shaft axis provided in the main assembly. Further, the coupling member may be decoupled from the drive shaft in a direction substantially perpendicular to the drive shaft axis. The present invention is applicable to a developing cartridge, an electrophotographic image forming apparatus using a detachably mountable developing cartridge, a process cartridge, and an electrophotographic image forming apparatus using a detachably mountable process cartridge.

The present invention can be applied to a so-called contact development system in which an electrostatic latent image formed on an electrophotographic photosensitive member is developed in a state in which the electrophotographic photosensitive member and a developing roller are in contact with each other.

The present invention can be applied to a so-called contact development system in which an electrostatic latent image formed on an electrophotographic photosensitive member is developed in a state in which the electrophotographic photosensitive member and a developing roller are separated from each other.

The developing roller can be smoothly rotated.

According to the embodiments of the present invention, the rotational force for rotating the photosensitive drum and the rotational force for rotating the developing roller can be received from the main assembly separately. According to various embodiments of the present invention, the structure for receiving the rotational force of the rotating photosensitive drum may employ a structure for moving the coupling in the axial direction thereof.

Although the present invention has been described with reference to the structures disclosed herein, it is not confined to the details set forth and this application is intended to cover such modifications or changes as may come within the purposes of the improvements or the scope of the following claims.

Claims (46)

1. A developing cartridge for use with a main assembly of an electrophotographic image forming apparatus, said main assembly including an electrophotographic photosensitive drum and a driving shaft having a rotational force applying portion, wherein said developing cartridge is detachable from the main assembly in a detaching direction substantially perpendicular to an axial direction of the driving shaft, said developing cartridge comprising:

i) a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive drum, the developing roller being rotatable about an axis thereof; and

ii) a coupling member engageable with the drive shaft to receive a rotational force for rotating the developing roller from the rotational force applying portion, the coupling member being capable of being at a rotational force transmitting angular position for transmitting the rotational force for rotating the developing roller to the developing roller and a disengaging angular position in which the coupling member is inclined away from the rotational force transmitting angular position,

wherein when the developing cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus in a dismounting direction substantially perpendicular to an axis of the developing roller, the coupling member is separated from the driving shaft by moving from the rotational force transmitting angular position to the separating angular position.

2. A developing cartridge for use with a main assembly of an electrophotographic image forming apparatus, said main assembly including an electrophotographic photosensitive drum and a driving shaft having a rotational force applying portion, wherein said developing cartridge is detachable from the main assembly in a detaching direction substantially perpendicular to an axial direction of the driving shaft, said developing cartridge comprising:

i) a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive drum, the developing roller being rotatable about an axis thereof; and

ii) a coupling member engageable with the drive shaft to receive a rotational force for rotating the developing roller from a rotational force applying portion, the coupling member being capable of being at a rotational force transmitting angular position for transmitting the rotational force for rotating the developing roller to the developing roller and a disengaging angular position in which the coupling member is inclined away from the rotational force transmitting angular position,

wherein in a state in which the developing cartridge is mounted to the main assembly of the electrophotographic image forming apparatus, a portion of the coupling member is located behind a driving shaft as viewed from a direction opposite to a detaching direction substantially perpendicular to an axis of the developing roller; wherein, when the developing cartridge is detached from the main assembly of the electrophotographic image forming apparatus, the coupling member is allowed to bypass the driving shaft by moving the coupling member from the rotational force transmitting angular position to the disengaging angular position, so that the coupling member is disengaged from the driving shaft.

3. A developing cartridge according to claim 1 or 2, wherein said coupling member has a recess extending coaxially with a rotational axis of said coupling member, and wherein said recess is above a free end of said driving shaft in a state in which said coupling member is at said rotational force transmitting angular position.

4. A developing cartridge according to claim 1 or 2, wherein said coupling member is rotated by a rotational force generated by engagement with a rotational force applying portion in a rotational direction of said coupling member, said rotational force applying portion projecting adjacent to the free end of the drive shaft in a direction substantially perpendicular to the axis of the drive shaft.

5. A developing cartridge according to claim 1 or 2, wherein when said developing cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus, said coupling member is pivoted from said rotational force transmitting angular position to said disengaging angular position, so that a part of the coupling member bypasses the driving shaft in accordance with the movement of said developing cartridge in the dismounting direction.

6. A cartridge according to claim 1 or 2, wherein a plurality of rotational force receiving portions are provided substantially at positions diametrically opposite to each other on a virtual circle having a center on the rotational axis of said coupling member.

7. A cartridge according to claim 1 or 2, wherein in a state in which the coupling member is at said rotational force transmitting angular position, a rotational axis of said coupling member is substantially coaxial or parallel with an axis of said developing roller.

8. A cartridge according to claim 7, wherein in a state in which said coupling member is at said detached angular position, a rotational axis of said coupling member is inclined with respect to an axis of said developing roller, thereby allowing an upstream portion of said coupling member to sweep a free end of the drive shaft in the detaching direction.

9. A cartridge according to claim 8, wherein in a state in which said coupling member is at said disengaging angular position, an angle at which a rotational axis of said coupling member is inclined with respect to an axis of said developing roller is 20 degrees to 60 degrees.

10. A developing cartridge according to claim 1 or 2, wherein the drum unit includes an electrophotographic photosensitive drum, and the drum unit is detachable from another portion of said main assembly.

11. A developing cartridge for use with a main assembly of an electrophotographic image forming apparatus, said main assembly including an electrophotographic photosensitive drum and a driving shaft having a rotational force applying portion, wherein said developing cartridge is mountable to and dismountable from the main assembly in a mounting direction substantially perpendicular to an axial direction of the driving shaft and in a dismounting direction opposite to the mounting direction, said developing cartridge comprising:

i) a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive drum, the developing roller being rotatable about an axis thereof; and

ii) a coupling member engageable with the drive shaft to receive a rotational force for rotating the developing roller from a rotational force applying portion, the coupling member being capable of assuming a rotational force transmitting angular position for transmitting the rotational force for rotating the developing roller to the developing roller, a pre-engagement angular position in which the coupling member is inclined away from the rotational force transmitting angular position, and a disengaging angular position in which the coupling member is inclined away from the rotational force transmitting angular position,

wherein the coupling member is engaged with the driving shaft by being moved from the pre-engagement angular position to the rotational force transmitting angular position when the developing cartridge is mounted to the main assembly of the electrophotographic image forming apparatus in a mounting direction substantially perpendicular to the developing roller axis; and wherein, when the developing cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus in a dismounting direction substantially perpendicular to the developing roller axis, the coupling member is separated from the driving shaft by moving from the rotational force transmitting angular position to the separating angular position.

12. A developing cartridge for use with a main assembly of an electrophotographic image forming apparatus, said main assembly including an electrophotographic photosensitive drum and a driving shaft having a rotational force applying portion, wherein said developing cartridge is mountable to and dismountable from the main assembly in a mounting direction substantially perpendicular to an axial direction of the driving shaft and in a dismounting direction opposite to the mounting direction, said developing cartridge comprising:

i) a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive drum, the developing roller being rotatable about an axis thereof; and

ii) a coupling member engageable with the drive shaft to receive a rotational force for rotating the developing roller from a rotational force applying portion, the coupling member being capable of assuming a rotational force transmitting angular position for transmitting the rotational force for rotating the developing roller to the developing roller, a pre-engagement angular position in which the coupling member is inclined away from the rotational force transmitting angular position, and a disengaging angular position in which the coupling member is inclined away from the rotational force transmitting angular position,

wherein, when the developing cartridge is mounted to the main assembly of the electrophotographic image forming apparatus in the mounting direction, the coupling member is pivoted from the pre-engagement angular position to the rotational force transmitting angular position such that a downstream portion of the coupling member with respect to the mounting direction bypasses the drive shaft; wherein, in a state in which the developing cartridge is mounted to the main assembly of the electrophotographic image forming apparatus, an upstream portion of the coupling member with respect to a dismounting direction is located behind a driving shaft as viewed from the mounting direction; and wherein, when said developing cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus in the dismounting direction, the coupling member is separated from the drive shaft by pivoting said coupling member from said rotational force transmitting angular position to said separating angular position so that the portion of the coupling member located behind the drive shaft bypasses the drive shaft in accordance with the movement of said developing cartridge in said dismounting direction.

13. A cartridge according to claim 11 or 12, wherein said coupling member has a recess in which a rotational axis of said coupling member extends.

14. A developing cartridge according to claim 11, wherein when said developing cartridge is mounted to the main assembly of the electrophotographic image forming apparatus in the mounting direction, said coupling member is pivoted from the pre-engagement angular position to the rotational force transmitting angular position such that a downstream portion of said coupling member with respect to the mounting direction bypasses the driving shaft.

15. A cartridge according to claim 13, wherein said recess is above a free end of said drive shaft in a state in which said coupling member is in said rotational force transmitting angular position.

16. A cartridge according to claim 11, wherein said coupling member is rotated by a rotational force generated by engagement with a rotational force applying portion in a rotational direction of said coupling member, said rotational force applying portion projecting adjacent to the free end of the drive shaft in a direction substantially perpendicular to the axis of the drive shaft.

17. A developing cartridge according to claim 11, wherein when said developing cartridge is dismounted in the dismounting direction from the main assembly of the electrophotographic image forming apparatus, said coupling member is separated from the driving shaft by pivoting said coupling member from said rotational force transmitting angular position to said separating angular position so that a part of said coupling member bypasses the driving shaft in accordance with the movement of said developing cartridge in the dismounting direction.

18. A developing cartridge according to claim 11 or 12, wherein a plurality of rotational force receiving portions are provided substantially at positions diametrically opposite to each other on a virtual circle having a center on the rotational axis of said coupling member.

19. A cartridge according to claim 11 or 12, wherein in the state in which the coupling member is at said rotational force transmitting angular position, a rotational axis of said coupling member is substantially coaxial or parallel with an axis of said developing roller.

20. A cartridge according to claim 19, wherein in a state in which the coupling member is at said detached angular position, a rotational axis of said coupling member is inclined with respect to an axis of said developing roller, thereby allowing an upstream portion of said coupling member to sweep a free end of the drive shaft in the detaching direction.

21. A cartridge according to claim 20, wherein in a state in which the coupling member is at said detached angular position, an angle at which a rotational axis of said coupling member is inclined with respect to an axis of said developing roller is 20 degrees to 60 degrees.

22. A cartridge according to claim 21, wherein in a state in which said coupling member is located at the pre-engagement angular position, said coupling member is inclined with respect to the axis of said developing roller so that a downstream portion of the coupling member with respect to the mounting direction passes over the free end of the drive shaft.

23. A cartridge according to claim 22, wherein in a state in which the coupling member is located at said pre-engagement angular position, an angle at which a rotational axis of said coupling member is inclined with respect to an axis of said developing roller is 20 degrees to 60 degrees.

24. A developing cartridge according to claim 11 or 12, wherein the drum unit includes an electrophotographic photosensitive drum, and the drum unit is detachable from another portion of said main assembly.

25. An electrophotographic image forming apparatus, comprising:

i) a main assembly of the electrophotographic image forming apparatus, the main assembly including an electrophotographic photosensitive drum and a driving shaft having a rotational force applying portion; and

ii) a developing cartridge detachably mountable to the main assembly, the developing cartridge including a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive drum, the developing roller being rotatable about an axis thereof, and a coupling member engageable with the driving shaft to receive a rotational force for rotating the developing roller from a rotational force applying portion, the coupling member being capable of assuming a rotational force transmitting angular position for transmitting the rotational force for rotating the developing roller to the developing roller and a disengaging angular position in which the coupling member is inclined away from the rotational force transmitting angular position,

wherein when the developing cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus in a dismounting direction substantially perpendicular to an axis of the developing roller, the coupling member is moved from the rotational force transmitting angular position to the disengaging angular position.

26. An electrophotographic image forming apparatus, comprising:

i) a main assembly of the electrophotographic image forming apparatus, the main assembly including an electrophotographic photosensitive drum and a driving shaft having a rotational force applying portion; and

ii) a developing cartridge detachably mountable to the main assembly, the developing cartridge including a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive drum, the developing roller being rotatable about an axis thereof, and a coupling member engageable with the driving shaft to receive a rotational force for rotating the developing roller from a rotational force applying portion, the coupling member being capable of assuming a rotational force transmitting angular position for transmitting the rotational force for rotating the developing roller to the developing roller and a disengaging angular position in which the coupling member is inclined away from the rotational force transmitting angular position,

wherein in a state in which the developing cartridge is mounted to the main assembly of the electrophotographic image forming apparatus, a part of the coupling member is located behind the driving shaft as viewed from a direction opposite to a detaching direction in which the developing cartridge is detached from the main assembly of the electrophotographic image forming apparatus; wherein when said developing cartridge is removed from the main assembly of the electrophotographic image forming apparatus, said coupling member is moved to the disengaging angular position from the rotational force transmitting angular position to allow said part of the coupling member to bypass the driving shaft, and thus said coupling member is disengaged from the driving shaft.

27. An apparatus according to claim 25 or 26, wherein said coupling member has a recess extending coaxially with a rotational axis of said coupling member, and wherein said recess is above a free end of said drive shaft in a state in which said coupling member is at said rotational force transmitting angular position.

28. An apparatus according to claim 25 or 26, wherein said coupling member is rotated by a rotational force generated by engagement with a rotational force applying portion in a rotational direction of said coupling member, said rotational force applying portion projecting adjacent to the free end of the drive shaft in a direction substantially perpendicular to the axis of the drive shaft.

29. An apparatus according to claim 25 or 26, wherein when said developing cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus, said coupling member is pivoted from said rotational force transmitting angular position to said disengaging angular position, so that a part of the coupling member bypasses the driving shaft in accordance with movement of said developing cartridge in the dismounting direction.

30. An apparatus according to claim 29, wherein a plurality of rotational force receiving portions are provided substantially at diametrically opposite positions to each other on a virtual circle having a center on the rotational axis of said coupling member.

31. An apparatus according to claim 25 or 26, wherein in the state in which the coupling member is in said rotational force transmitting angular position, a rotational axis of said coupling member is substantially coaxial or parallel with an axis of said developing roller.

32. An apparatus according to claim 31, wherein in a state in which said coupling member is at said separated angular position, a rotational axis of said coupling member is inclined with respect to an axis of said developing roller, thereby allowing an upstream portion of said coupling member to sweep a free end of the driving shaft in the detaching direction.

33. An apparatus according to claim 32, wherein in a state in which the coupling member is at said separated angular position, an angle at which a rotational axis of said coupling member is inclined with respect to an axis of said developing roller is 20 degrees to 60 degrees.

34. An electrophotographic image forming apparatus, comprising:

i) a main assembly of the electrophotographic image forming apparatus, the main assembly including an electrophotographic photosensitive drum and a driving shaft having a rotational force applying portion; and

ii) a developing cartridge detachably mountable to the main assembly, the developing cartridge including a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive drum, the developing roller being rotatable about an axis thereof, and a coupling member engageable with the driving shaft to receive a rotational force for rotating the developing roller from a rotational force applying portion, the coupling member being capable of assuming a rotational force transmitting angular position for transmitting the rotational force for rotating the developing roller to the developing roller, a pre-engagement angular position in which the coupling member is inclined away from the rotational force transmitting angular position, and a disengaging angular position in which the coupling member is inclined away from the rotational force transmitting angular position,

wherein when said developing cartridge is mounted to the main assembly of the electrophotographic image forming apparatus in a mounting direction substantially perpendicular to the developing roller axis, said coupling member is moved from the pre-engagement angular position to the rotational force transmitting angular position to engage with the driving shaft; and wherein when said developing cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus in a dismounting direction opposite to the mounting direction, said coupling member is separated from the driving shaft by being moved from said rotational force transmitting angular position to said separating angular position.

35. An electrophotographic image forming apparatus, comprising:

i) a main assembly of the electrophotographic image forming apparatus, the main assembly including an electrophotographic photosensitive drum and a driving shaft having a rotational force applying portion, the driving shaft being rotatable by a motor; and

ii) a developing cartridge detachably mountable to the main assembly, the developing cartridge including a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive drum, the developing roller being rotatable about an axis thereof, and a coupling member engageable with the driving shaft to receive a rotational force for rotating the developing roller from a rotational force applying portion, the coupling member being capable of assuming a rotational force transmitting angular position for transmitting the rotational force for rotating the developing roller to the developing roller, a pre-engagement angular position in which the coupling member is inclined away from the rotational force transmitting angular position, and a disengaging angular position in which the coupling member is inclined away from the rotational force transmitting angular position,

wherein, when the developing cartridge is mounted to the main assembly of the electrophotographic image forming apparatus in a mounting direction substantially perpendicular to the developing roller axis, the coupling member is pivoted from the pre-engagement angular position to the rotational force transmitting angular position such that a downstream portion of the coupling member with respect to the mounting direction bypasses the drive shaft; wherein, in a state in which the developing cartridge is mounted to the main assembly of the electrophotographic image forming apparatus, an upstream portion of the coupling member with respect to a dismounting direction opposite to the mounting direction is located behind the driving shaft as viewed from the mounting direction; and wherein, when said developing cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus, the coupling member is separated from the driving shaft by pivoting said coupling member from said rotational force transmitting angular position to said separating angular position so that a portion of the coupling member located behind the driving shaft passes by the driving shaft in accordance with the movement of said developing cartridge in the dismounting direction.

36. An apparatus according to claim 34 or 35, wherein said coupling member has a recess in which a rotational axis of said coupling member extends.

37. An apparatus according to claim 34 or 35, wherein when said developing cartridge is mounted to the main assembly of the apparatus in the mounting direction, said coupling member is pivoted from the pre-engagement angular position to the rotational force transmitting angular position such that a downstream portion of said coupling member with respect to the mounting direction bypasses the driving shaft.

38. An apparatus according to claim 36, wherein said recess is above a free end of said drive shaft in a state in which said coupling member is at said rotational force transmitting angular position.

39. An apparatus according to claim 34 or 35, wherein said coupling member is rotated by a rotational force generated by engagement with a rotational force applying portion in a rotational direction of said coupling member, said rotational force applying portion projecting adjacent to the free end of the drive shaft in a direction substantially perpendicular to the axis of the drive shaft.

40. An apparatus according to claim 34 or 35, wherein when said developing cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus in the dismounting direction, said coupling member is separated from the driving shaft by pivoting said coupling member from said rotational force transmitting angular position to said separating angular position so that a portion of said coupling member bypasses the driving shaft in accordance with the movement of said developing cartridge in the dismounting direction.

41. An apparatus according to claim 34 or 35, wherein a plurality of rotational force receiving portions are provided substantially at diametrically opposite positions to each other on a virtual circle having a center on the rotational axis of said coupling member.

42. An apparatus according to claim 34 or 35, wherein in the state in which the coupling member is in said rotational force transmitting angular position, a rotational axis of said coupling member is substantially coaxial or parallel with an axis of said developing roller.

43. An apparatus according to claim 42, wherein in a state in which the coupling member is at said separated angular position, a rotational axis of said coupling member is inclined with respect to an axis of said developing roller, thereby allowing an upstream portion of said coupling member to sweep a free end of the driving shaft in the detaching direction.

44. An apparatus according to claim 43, wherein in a state in which the coupling member is at said separated angular position, an angle at which a rotational axis of said coupling member is inclined with respect to an axis of said developing roller is 20 to 60 degrees.

45. An apparatus according to claim 44, wherein in a state in which said coupling member is located at the pre-engagement angular position, said coupling member is inclined with respect to the axis of said developing roller such that a downstream portion of the coupling member with respect to the mounting direction passes over the free end of the drive shaft.

46. An apparatus according to claim 45, wherein in a state in which the coupling member is located at said pre-engagement angular position, a rotational axis of said coupling member is inclined at an angle of 20 to 60 degrees with respect to an axis of said developing roller.