JP7726345B2 - Image forming device - Google Patents

Description

The present invention relates to an image forming apparatus.

Electrophotographic image forming devices such as laser printers and LED printers are well known. A developer cartridge is used in these image forming devices. The developer cartridge has a developer roller for supplying toner. Conventional image forming devices are described, for example, in Patent Documents 1 and 2. The image forming device in Patent Document 1 has a drawer unit. The drawer unit has a photosensitive drum. The developer cartridge is attached to the drawer unit. When the developer cartridge is attached to the drawer unit, the photosensitive drum and the developer roller come into contact.

The developer cartridge in Patent Document 2 is attached to a drum cartridge. The drum cartridge has a photosensitive drum. When the developer cartridge is attached to the drum cartridge, the photosensitive drum comes into contact with the developing roller. The drum cartridge with the attached developer cartridge is then attached to the image forming device.

The image forming device performs a separation operation as needed. During this operation, the developing roller is temporarily separated from the photosensitive drum. For example, in a color printer, when performing monochrome printing, the developing rollers of the developer cartridges other than the black one are separated from the photosensitive drum. At this time, the position of the housing of the developer cartridge relative to the drawer unit or drum cartridge changes.

JP 2011-59510 A JP 2013-54058 A

Developer cartridges with storage media are also known. The storage medium is, for example, an IC chip. The storage medium has an electrical contact surface. The electrical contact surface of the storage medium contacts a terminal portion provided on the image forming device or the drawer unit. Developer cartridges with electrodes are also known. The electrodes receive power from the image forming device. The electrodes also have an electrical contact surface. The electrical contact surface of the electrodes contacts a terminal portion provided on the image forming device or the drawer unit.

However, when an image forming device performs a separation operation on a developer cartridge having an electrical contact surface, the relative positional relationship between the electrical contact surface and the terminal portion changes as the position of the housing changes. As a result, the electrical contact surface and the terminal portion rub against each other each time a separation operation is performed.

The object of the present invention is to reduce friction on electrical contact surfaces in an image forming apparatus that uses a developer cartridge having electrical contact surfaces.

To solve the above problem, the first invention of the present application is an image forming apparatus comprising: a photosensitive drum rotatable about a first axis extending in a first direction; a developer cartridge comprising a housing capable of containing developer, a developer roller rotatable about a second axis extending in the first direction, a storage medium having an electrical contact surface; and a holder located on one side of the housing in the first direction, extending in a second direction intersecting the electrical contact surface, and holding the electrical contact surface on a first outer surface located on one side of the second direction; and a frame to which the developer cartridge can be attached, the frame having electrical contacts that contact the electrical contact surface of the developer cartridge attached to the frame; and the housing is movable relative to the holder in a direction in which the developer roller moves away from the photosensitive drum while the electrical contact surface and the electrical contact are in contact.

The second invention of the present application is the image forming apparatus of the first invention, wherein the holder further comprises a second outer surface located on the other side of the second direction and movable in the second direction relative to the first outer surface, and an elastic member located between the first outer surface and the second outer surface and expandable in the second direction, and wherein the electrical contact surface comes into contact with the electrical contact due to the elastic force of the elastic member.

The third invention of the present application is the image forming apparatus of the second invention, characterized in that the frame has a first guide plate having the electrical contact and a second guide plate that contacts the second outer surface, and the length in the second direction between the electrical contact and the second guide plate is shorter than the length in the second direction between the electrical contact surface of the developer cartridge and the second outer surface before installation.

The fourth invention of the present application is the image forming apparatus of the third invention, characterized in that when the developer cartridge is inserted into the frame, the second outer surface moves along the second guide plate, bringing the second outer surface closer to the first outer surface and shortening the length of the elastic member in the second direction.

The fifth invention of the present application is an image forming apparatus according to the third or fourth invention, characterized in that the housing is movable in the separation direction relative to the holder while the second outer surface is in contact with the second guide plate and the electrical contact surface is in contact with the electrical contact.

The sixth aspect of the present invention is an image forming apparatus according to any one of the first to fifth aspects, further comprising a pressing member that presses the housing in the separating direction.

The seventh invention of the present application is the image forming apparatus of the sixth invention, characterized in that the pressure of the pressing member causes the developing roller and the photosensitive drum to change from a contact state in which they are in contact with each other to a separated state in which they are separated from each other, and in both the contact state and the separated state, the electrical contact surface and the electrical contact are in contact.

The eighth invention of the present application is an image forming apparatus according to any one of the first to seventh inventions, wherein the developing cartridge further has a holder cover fixed to the housing that holds the holder between the developing cartridge and the housing, and the housing and the holder cover are movable in the separating direction relative to the holder while the electrical contact surface and the electrical contact are in contact.

The ninth invention of the present application is an image forming apparatus according to any one of the first to eighth inventions, characterized in that the storage medium is an IC chip having the electrical contact surface.

The tenth aspect of the present invention is an image forming apparatus according to any one of the first to ninth aspects, characterized in that the frame includes the photosensitive drum.

The eleventh invention of the present application is the image forming apparatus of the tenth invention, characterized in that the frame has a plurality of slots into which the developing cartridges can be attached, and each slot is provided with a photosensitive drum.

The twelfth invention of the present application is an image forming apparatus comprising a developer cartridge including a housing capable of containing developer, a developing roller rotatable about an axis extending in a first direction, a storage medium having an electrical contact surface, and a holder located on one side of the housing in the first direction, extending in a second direction intersecting the electrical contact surface, and holding the electrical contact surface on a first outer surface located on one side of the second direction; and a frame into which the developer cartridge can be inserted in an insertion direction, wherein the frame has electrical contacts that contact the electrical contact surface of the developer cartridge attached to the frame, and the housing is movable in the insertion direction relative to the holder while the electrical contact surface and the electrical contact are in contact.

The thirteenth invention of the present application is an image forming apparatus comprising: a developer cartridge including a housing capable of containing developer, a developing roller, an electrical contact surface, and a holder that holds the electrical contact surface; and a frame to which the developer cartridge can be attached, wherein the frame has electrical contacts that come into contact with the electrical contact surface of the developer cartridge attached to the frame, and wherein, with the electrical contact surface and the electrical contacts in contact, the housing is movable relative to the holder in a direction that intersects with the direction in which the electrical contact surface and the electrical contacts face each other.

According to the first to thirteenth aspects of the present application, the housing can be moved relative to the holder while maintaining contact between the electrical contact surfaces and the electrical contacts. This reduces friction on the electrical contact surfaces.

Furthermore, according to the second invention of the present application, contact between the electrical contact surface and the electrical contact can be maintained by using an elastic member.

Furthermore, according to the third aspect of the present invention, the elastic member can be compressed in the second direction beyond its natural length to generate a repulsive force in the elastic member. This allows contact between the electrical contact surface and the electrical contact to be maintained.

Furthermore, according to the fifth aspect of the present invention, the holder can be fixed between the first guide plate and the second guide plate, while the housing can be smoothly moved away from the holder.

Furthermore, according to the eighth aspect of the present invention, the housing and holder cover can be moved smoothly relative to the holder.

FIG. 1 is a conceptual diagram of an image forming apparatus. FIG. 2 is a perspective view of the drawer unit and the developing cartridge. FIG. FIG. FIG. 2 is an exploded perspective view of an IC chip assembly. FIG. 2 is a cross-sectional view of an IC chip assembly. FIG. FIG. 4 is a cross-sectional view of a first guide plate and a second guide plate. FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. FIG. 10 is a diagram showing a state when a separating operation is performed.

A preferred embodiment of the present invention will be described below with reference to the drawings.

1. Configuration of Image Forming Apparatus
FIG. 1 is a conceptual diagram of an image forming apparatus 100. This image forming apparatus 100 is an electrophotographic printer. Examples of the image forming apparatus 100 include a laser printer and an LED printer. The image forming apparatus 100 includes four developer cartridges 1 and a drawer unit 90. The drawer unit 90 is a frame into which the four developer cartridges 1 can be attached. The image forming apparatus 100 forms an image on the recording surface of printing paper using developer (e.g., toner) supplied from the four developer cartridges 1.

Figure 2 is a perspective view of the drawer unit 90 and the developer cartridges 1. As shown in Figures 1 and 2, the four developer cartridges 1 can be individually replaced with respect to the drawer unit 90. When replacing a developer cartridge 1, the drawer unit 90 is pulled out from the front of the image forming apparatus 100. The developer cartridges 1 are then removed and installed into each of the four slots 91 provided in the drawer unit 90. The drawer unit 90 has four photosensitive drums 92. The photosensitive drums 92 are located near the bottom of each of the four slots 91. The photosensitive drums 92 are rotatable about a horizontally extending rotation axis (first axis). Hereinafter, the direction in which the rotation axis of the photosensitive drum 92 extends is referred to as the "first direction."

In this embodiment, four developer cartridges 1 are attached to one drawer unit 90. The four developer cartridges 1 contain developers of different colors (for example, cyan, magenta, yellow, and black). However, the number of developer cartridges 1 attached to the drawer unit 90 may be one to three, or may be five or more.

As shown in Figures 1 and 2, each of the four developer cartridges 1 has an IC chip 61. The IC chip 61 is a storage medium from which information can be read and written. The image forming device 100 also has a control unit 80. When the four developer cartridges 1 are attached to the drawer unit 90, the IC chip 61 of each developer cartridge 1 is electrically connected to the control unit 80. The control unit 80 is formed, for example, by a circuit board. The control unit 80 has a processor such as a CPU and various memories. The control unit 80 executes various processes in the image forming device 100 by causing the processor to operate in accordance with a program.

<2. Overall structure of developing cartridge>
3 and 4 are perspective views of the developer cartridge 1. As shown in Fig. 3 and 4, the developer cartridge 1 of this embodiment has a casing 10, an agitator 20, a development roller 30, a first gear portion 40, a second gear portion 50, and an IC chip assembly 60.

The casing 10 is a housing capable of containing developer. The casing 10 extends in a first direction between a first end face 11 and a second end face 12. The first gear portion 40 and the IC chip assembly 60 are located at the first end face 11. The second gear portion 50 is located at the second end face 12. A storage chamber 13 is provided inside the casing 10. The developer is stored in the storage chamber 13. The casing 10 has an opening 14. The opening 14 is located at the end of the casing 10 in the insertion direction of the developer cartridge 1 into the drawer unit 90. The storage chamber 13 communicates with the outside via the opening 14.

The agitator 20 has an agitator shaft 21 and an agitator blade 22. The agitator shaft 21 extends along the first direction. The agitator blade 22 extends radially outward from the agitator shaft 21. At least a portion of the agitator shaft 21 and the agitator blade 22 are disposed inside the storage chamber 13. A first agitator gear 44 and a second agitator gear 51, described below, are respectively connected to both ends of the agitator shaft 21 in the first direction. Therefore, the agitator shaft 21 and the agitator blade 22 rotate together with the first agitator gear 44 and the second agitator gear 51. When the agitator blade 22 rotates, the developer in the storage chamber 13 is agitated.

The developing roller 30 is a roller that can rotate about a rotation axis (second axis) that extends in the first direction. The developing roller 30 is disposed in the opening 14 of the casing 10. In this embodiment, the developing roller 30 has a developing roller main body 31 and a developing roller shaft 32. The developing roller main body 31 is a cylindrical member that extends in the first direction. The developing roller main body 31 is made of a material such as elastic rubber. The developing roller shaft 32 is a cylindrical member that penetrates the developing roller main body 31 in the first direction. The developing roller shaft 32 is made of a material such as metal or a conductive resin. The developing roller main body 31 is fixed to the developing roller shaft 32 so that it cannot rotate relative to it.

One end of the developing roller shaft 32 in the first direction is fixed to the developing roller gear 42 (described below) so that it cannot rotate relative to the developing roller gear 42. Therefore, when the developing roller gear 42 rotates, the developing roller shaft 32 also rotates, and the developing roller main body 31 rotates together with the developing roller shaft 32.

The developing roller shaft 32 does not have to penetrate the developing roller main body 31 in the first direction. For example, a pair of developing roller shafts 32 may extend in the first direction from both ends of the developing roller main body 31 in the first direction.

The developer cartridge 1 also has a supply roller (not shown). The supply roller is located between the developer roller 30 and the storage chamber 13. The supply roller is rotatable about a rotation axis extending in the first direction. When the developer cartridge 1 receives a driving force, developer is supplied from the storage chamber 13 inside the casing 10 to the outer circumferential surface of the developer roller 30 via the supply roller. At this time, the developer is frictionally charged between the supply roller and the developer roller 30. Meanwhile, a bias voltage is applied to the developer roller shaft 32 of the developer roller 30. Therefore, the developer is attracted to the outer circumferential surface of the developer roller body 31 due to the electrostatic force between the developer roller shaft 32 and the developer.

The developer cartridge 1 also has a layer thickness regulating blade (not shown). The layer thickness regulating blade shapes the developer supplied to the outer peripheral surface of the developing roller main body 31 to a uniform thickness. The developer on the outer peripheral surface of the developing roller main body 31 is then supplied to the photosensitive drum 92 provided in the drawer unit 90. At this time, the developer moves from the developing roller main body 31 to the photosensitive drum 92 in accordance with the electrostatic latent image formed on the outer peripheral surface of the photosensitive drum 92. This makes the electrostatic latent image visible on the outer peripheral surface of the photosensitive drum 92.

The first gear portion 40 is located on the first end surface 11 of the casing 10. Figure 3 is an oblique view of the developer cartridge 1 with the first gear portion 40 disassembled. As shown in Figure 3, the first gear portion 40 has a coupling 41, a developing roller gear 42, an idle gear 43, a first agitator gear 44, and a first cover 45. Note that Figure 3 does not show the multiple gear teeth of each gear.

The coupling 41 is the gear that first receives the driving force supplied from the image forming apparatus 100. The coupling 41 is capable of rotating about a rotation axis extending in the first direction. The coupling 41 has a coupling portion 411 and a coupling gear 412. The coupling portion 411 and the coupling gear 412 are integrally formed from, for example, resin. The coupling portion 411 is provided with a fastening hole 413 that is recessed in the first direction. In addition, the outer periphery of the coupling gear 412 is provided with a plurality of gear teeth at equal intervals around the entire circumference.

When the drawer unit 90 with the developer cartridge 1 installed is stored inside the image forming device 100, the drive shaft of the image forming device 100 is inserted into the fastening hole 413 of the coupling part 411. This connects the drive shaft and coupling part 411 so that they cannot rotate relative to each other. Therefore, when the drive shaft rotates, the coupling part 411 rotates, and the coupling gear 412 rotates along with the coupling part 411.

The developing roller gear 42 is a gear for rotating the developing roller 30. The developing roller gear 42 is capable of rotating about a rotation axis extending in the first direction. The outer periphery of the developing roller gear 42 is provided with multiple gear teeth at equal intervals around the entire circumference. Some of the multiple gear teeth of the coupling gear 412 and some of the multiple gear teeth of the developing roller gear 42 mesh with each other. The developing roller gear 42 is also fixed to the end of the developing roller shaft 32 in the first direction so that it cannot rotate relative to the developing roller gear 42. Therefore, when the coupling gear 412 rotates, the developing roller gear 42 rotates, and the developing roller 30 rotates along with the developing roller gear 42.

The idle gear 43 is a gear that transmits the rotation of the coupling gear 412 to the first agitator gear 44. The idle gear 43 is rotatable about a rotation axis extending in the first direction. The idle gear 43 has a large diameter gear portion 431 and a small diameter gear portion 432 arranged in the first direction. The small diameter gear portion 432 is located between the large diameter gear portion 431 and the first end face 11 of the casing 10. In other words, the large diameter gear portion 431 is farther from the first end face 11 than the small diameter gear portion 432. The diameter of the tip circle of the small diameter gear portion 432 is smaller than the diameter of the tip circle of the large diameter gear portion 431. The large diameter gear portion 431 and the small diameter gear portion 432 are integrally formed, for example, from resin.

The large diameter gear portion 431 and the small diameter gear portion 432 each have a plurality of gear teeth evenly spaced around the entire circumference on their outer peripheries. The number of gear teeth on the small diameter gear portion 432 is fewer than the number of gear teeth on the large diameter gear portion 431. Some of the gear teeth on the coupling gear 412 and some of the gear teeth on the large diameter gear portion 431 mesh with each other. Some of the gear teeth on the small diameter gear portion 432 mesh with some of the gear teeth on the first agitator gear 44. When the coupling gear 412 rotates, the large diameter gear portion 431 rotates, and the small diameter gear portion 432 rotates along with the large diameter gear portion 431. As the small diameter gear portion 432 rotates, the first agitator gear 44 also rotates.

The first agitator gear 44 is a gear for rotating the agitator 20 in the storage chamber 13. The first agitator gear 44 is rotatable about a rotation axis extending in the first direction. A plurality of gear teeth are provided at equal intervals around the outer periphery of the first agitator gear 44. As described above, some of the gear teeth of the small diameter gear portion 432 and some of the gear teeth of the first agitator gear 44 mesh with each other. The first agitator gear 44 is fixed to one end of the agitator shaft 21 in the first direction so as not to rotate relative to the agitator gear 44. Therefore, when power is transmitted from the coupling 41 to the first agitator gear 44 via the idle gear 43, the first agitator gear 44 rotates, and the agitator 20 rotates along with the first agitator gear 44.

The first cover 45 is fixed to the first end surface 11 of the casing 10, for example, by screws. The coupling gear 412, developing roller gear 42, idle gear 43, and first agitator gear 44 are housed between the first end surface 11 and the first cover 45. The fastening hole 413 of the coupling portion 411 is exposed to the outside of the first cover 45. The first cover 45 also has a first columnar protrusion 46 extending in the first direction. In this embodiment, the first cover 45 also serves as a holder cover that holds the holder 62 of the IC chip assembly 60, which will be described later. The structure of the first cover 45 as a holder cover will be described later.

The second gear portion 50 is located on the second end surface 12 of the casing 10. Figure 4 is an oblique view of the developer cartridge 1 with the second gear portion 50 disassembled. As shown in Figure 4, the second gear portion 50 has a second agitator gear 51, a detection gear 52, a conductive member 53, and a second cover 54. Note that Figure 4 omits the illustration of the multiple gear teeth of the second agitator gear 51.

The second agitator gear 51 is a gear that transmits the rotation of the agitator shaft 21 to the detection gear 52. The second agitator gear 51 is rotatable about a rotation axis that extends in the first direction. The outer periphery of the second agitator gear 51 is provided with multiple gear teeth that are evenly spaced around the entire circumference. When the developer cartridge 1 is new (unused), some of the multiple gear teeth of the second agitator gear 51 can mesh with some of the multiple gear teeth of the detection gear 52. The second agitator gear 51 is fixed to the other end of the agitator shaft 21 in the first direction so that it cannot rotate relative to the agitator shaft 21. Therefore, when the agitator shaft 21 rotates, the second agitator gear 51 also rotates.

The detection gear 52 is a gear that transmits information about the developer cartridge 1 to the image forming apparatus 100. The information about the developer cartridge 1 includes information about whether the developer cartridge 1 is a new (unused) developer cartridge or a used developer cartridge. The information about the developer cartridge 1 also includes the specifications of the developer cartridge 1. The specifications of the developer cartridge 1 include, for example, the amount of developer in the developer cartridge 1 or yield information that indicates the number of pages that can be printed using the developer.

The detection gear 52 is rotatable about a rotation axis extending in the first direction. The detection gear 52 has multiple gear teeth on a portion of its outer periphery. When a new developer cartridge 1 is attached to the drawer unit 90 and the drawer unit 90 is stored in the image forming device 100, the coupling 41 receives driving force from the image forming device 100. The second agitator gear 51 then rotates due to the driving force transmitted from the coupling 41 via the idle gear 43, the first agitator gear 44, and the agitator 20. The detection gear 52 rotates by meshing with the second agitator gear 51. However, the detection gear 52 has gear teeth only on a portion of its outer periphery. Therefore, when the detection gear 52 rotates a predetermined angle, the second agitator gear 51 and the detection gear 52 disengage, and the detection gear 52 stops rotating.

In this way, in a developer cartridge 1 that has been used once in the image forming device 100, the second agitator gear 51 and the detection gear 52 are no longer meshed together. Therefore, if a used developer cartridge 1 is removed from the image forming device 100 and then re-installed in the image forming device 100, the rotation of the second agitator gear 51 is not transmitted to the detection gear 52. Therefore, the detection gear 52 does not rotate.

Note that other gears may be disposed between the second agitator gear 51 and the detection gear 52. For example, the second gear section 50 may have a second idle gear that meshes with both the second agitator gear 51 and the detection gear 52. The rotation of the second agitator gear 51 may then be transmitted to the detection gear 52 via the second idle gear.

As shown in FIG. 4 , the detection gear 52 has a detection protrusion 521. The detection protrusion 521 protrudes in a first direction. The detection protrusion 521 also extends in an arc shape centered on the rotation axis of the detection gear 52. When the detection gear 52 rotates, the detection protrusion 521 also rotates. In other words, the position of the detection protrusion 521 changes as the detection gear 52 rotates.

The conductive member 53 is an electrically conductive member. The conductive member 53 is made of a conductive metal or a conductive resin. The conductive member 53 is located on the second end surface 12 of the casing 10. The conductive member 53 has a cylindrical gear shaft 531 that protrudes in the first direction. The detection gear 52 is supported by the gear shaft 531 and rotates around the gear shaft 531. The detection protrusion 521 partially covers the periphery of the gear shaft 531. The conductive member 53 also has a bearing portion 532. The bearing portion 532 contacts the developing roller shaft 32 of the developing roller 30.

The drawer unit 90 has a conductive lever (not shown) that contacts the gear shaft 531, and an optical sensor (not shown). When the lever contacts the gear shaft 531, the conductive member 53 and the developing roller shaft 32 become electrically conductive with the lever. When the image forming apparatus 100 is operating, the developing roller shaft 32 is maintained at a predetermined bias voltage by the power supplied from the lever.

The detection protrusion 521 partially covers the outer surface of the gear shaft 531. Therefore, when a new developer cartridge 1 is inserted into the drawer unit 90 and the detection gear 52 is rotating, the contact state between the lever and the gear shaft 531 changes depending on the shape of the detection gear 52. In other words, the lever temporarily separates from the gear shaft 531. The image forming device 100 detects the displacement of the lever using an optical sensor. The control unit 80 of the image forming device 100 then identifies whether the installed developer cartridge 1 is new and the specifications of the developer cartridge 1 based on the detection signal obtained from the optical sensor.

In this way, in this embodiment, the optical sensor detects the movement of the detection protrusion 521 via the lever. However, the optical sensor may also directly detect the movement of the first protrusion. Also, a magnetic sensor or contact sensor may be used instead of the optical sensor. Furthermore, the movement of the detection protrusion 521 may be detected based on the presence or absence of electrical conduction between the lever and the gear shaft 531.

In addition, in this embodiment, the gear shaft 531 is part of the conductive member 53. However, the gear shaft may be provided separately from the power supply path to the conductive member 53. For example, the casing 10 may further have a through hole penetrating the second end face 12 and a cap attached to the through hole, with the gear shaft extending from the cap in the first direction.

The circumferential position and length of the detection protrusion 521 may differ from the example shown in Figure 4. The detection gear 52 may also have multiple detection protrusions 521. The number of detection protrusions 521, the circumferential position of each detection protrusion 521, the circumferential length of each detection protrusion 521, and the radial length of each detection protrusion 521 may differ depending on the specifications of the developer cartridge 1. In this way, by providing variations in the number and shape of the detection protrusions 521, various specifications of the developer cartridge 1 can be presented to the image forming apparatus 100.

The detection gear 52 may also be composed of multiple components. For example, the detection gear 52 and the detection protrusion 521 may be separate components. The detection gear may also have a detection gear main body and an auxiliary member whose position changes in response to the rotation of the detection gear main body. The auxiliary member may then change the position of the lever. The detection gear may also have a detection gear main body, a cam that rotates in response to the rotation of the detection gear main body, and a detection protrusion that is displaced by the rotation of the cam.

The detection gear 52 may also be a movable gear that moves in a first direction as it rotates. The movement of the detection gear 52 in the first direction may disengage the second agitator gear 51 from the detection gear 52. In this case, multiple gear teeth may be provided around the entire outer periphery of the detection protrusion 521. The detection gear 52 may move in a direction away from the second end face 12, or in a direction toward the second end face 12.

The second cover 54 is fixed to the second end surface 12 of the casing 10, for example, by screws. The second agitator gear 51, the detection gear 52, and the conductive member 53 are housed between the second end surface 12 and the second cover 54. The second cover 54 also has an opening 541. A portion of the detection protrusion 521 and a portion of the gear shaft 531 are exposed through the opening 541. The lever described above comes into contact with the detection gear 52 or the gear shaft 531 through the opening 541.

As shown in FIG. 4 , the casing 10 also has a second columnar protrusion 55. The second columnar protrusion 55 protrudes in the first direction from the second end surface 12 of the casing 10. The second columnar protrusion 55 is exposed from the second cover 54.

<3. IC Chip Assembly>
The IC chip assembly 60 is disposed on the outside of the first end surface 11 of the casing 10. FIG. 5 is an exploded perspective view of the IC chip assembly 60. FIG. 6 is a cross-sectional view of the IC chip assembly 60 cut along a plane perpendicular to the first direction. As shown in FIGS. 3 to 6, the IC chip assembly 60 includes an IC chip 61, which is a storage medium, and a holder 62 that holds the IC chip 61. The IC chip 61 is fixed to the outer surface of the holder 62. The holder 62 is held between the casing 10 and the first cover 45. The IC chip 61 has an electrical contact surface 611. The electrical contact surface 611 is made of a metal, which is a conductor. The IC chip 61 can also store various pieces of information related to the developer cartridge 1.

Hereinafter, the direction intersecting the electrical contact surface 611 (in this embodiment, the direction perpendicular to the electrical contact surface 611) will be referred to as the "second direction." Furthermore, the insertion direction of the developer cartridge 1 into the slot 91 of the drawer unit 90 will be referred to as the "third direction."

A portion of the holder 62 is covered by the first cover 45. The holder 62 has a first boss 621a, a second boss 621b, and a third boss 621c. The first boss 621a and the second boss 621b each extend in a first direction from the surface of the holder 62 opposite the surface facing the casing 10 toward the first cover 45. The first boss 621a and the second boss 621b are aligned in the third direction. As shown in FIG. 3, the first cover 45 has a first through hole 451a and a second through hole 451b. The first through hole 451a and the second through hole 451b each penetrate the first cover 45 in the first direction. The first through hole 451a and the second through hole 451b are aligned in the third direction. The first boss 621a is inserted into the first through hole 451a. The second boss 621b is inserted into the second through-hole 451b.

The third boss 621c extends in a first direction from the surface of the holder 62 facing the casing 10 toward the casing 10. Meanwhile, the casing 10 has a recess 15. The recess 15 is recessed in the first direction in the first end surface 11 of the casing 10. The third boss 621c is inserted into the recess 15. The first boss 621a, the second boss 621b, and the third boss 621c may each have a cylindrical shape or another shape such as a rectangular pillar.

The size (internal dimension) of the first through hole 451a in the second direction is larger than the size (external dimension) of the first boss 621a. The size (internal dimension) of the second through hole 451b in the second direction is larger than the size (external dimension) of the second boss 621b. Furthermore, the size (internal dimension) of the recess 15 in the second direction is larger than the size (external dimension) of the third boss 621c. Therefore, the holder 62, together with the first boss 621a, second boss 621b, and third boss 621c, can move in the second direction relative to the casing 10 and first cover 45. When the holder 62 moves in the second direction, the IC chip 61 having the electrical contact surface 611 also moves in the second direction along with the holder 62.

The size (internal dimension) of the first through hole 451a in the third direction is larger than the size (external dimension) of the first boss 621a. The size (internal dimension) of the second through hole 451b in the third direction is larger than the size (external dimension) of the second boss 621b. The size (internal dimension) of the recess 15 in the third direction is larger than the size (external dimension) of the third boss 621c. Therefore, the holder 62, together with the first boss 621a, the second boss 621b, and the third boss 621c, can move in the third direction relative to the casing 10 and the first cover 45. When the holder 62 moves in the third direction, the IC chip 61 having the electrical contact surface 611 also moves in the third direction together with the holder 62.

The holder 62 may be movable in the first direction between the first end surface 11 of the casing 10 and the first cover 45. The number of bosses provided on the holder 62, the number of through holes provided in the first cover 45, and the number of recesses provided in the casing 10 are not limited to the example of this embodiment. Instead of through holes, the first cover 45 may have recesses into which the bosses are inserted.

As shown in Figures 5 and 6, the holder 62 has a first outer surface 710 and a second outer surface 720. The first outer surface 710 is located at one end of the holder 62 in the second direction. The second outer surface 720 is located at the other end of the holder 62 in the second direction. The second outer surface 720 is movable in the second direction relative to the first outer surface 710.

More specifically, the holder 62 of this embodiment has a first holder member 71, a second holder member 72, and a coil spring 73 positioned therebetween. The first holder member 71 is made of, for example, resin. The second holder member 72 is made of, for example, resin. The first holder member 71 has a first outer surface 710. The IC chip 61 is fixed to a holding surface 620 included in the first outer surface 710. The second holder member 72 has a second outer surface 720. In the assembled holder 62, the first outer surface 710 and the second outer surface 720 are spaced apart in the second direction.

The coil spring 73 is an elastic member that extends in the second direction. The coil spring 73 is disposed between the first outer surface 710 and the second outer surface 720 in the second direction. The coil spring 73 expands and contracts in the second direction at least between a first state and a second state that is more contracted than the first state. The length of the coil spring 73 in the second direction in the first state is longer than the length of the coil spring 73 in the second state. Therefore, the distance in the second direction between the first outer surface 710 and the second outer surface 720 in the first state is longer than the distance in the second direction between the first outer surface 710 and the second outer surface 720 in the second state. Furthermore, the length of the coil spring 73 in the second direction in at least the second state is shorter than the natural length of the coil spring 73.

As shown in Figures 5 and 6, the first holder member 71 has a first claw portion 715a and a second claw portion 715b. The first claw portion 715a and the second claw portion 715b each protrude from the first holder member 71 in a direction intersecting the second direction. Meanwhile, the second holder member 72 has a first opening 721a and a second opening 721b. The first claw portion 715a is inserted into the first opening 721a. The second claw portion 715b is inserted into the second opening 721b. In the first state, the first claw portion 715a contacts the second holder member 72 at the edge of the first opening 721a on the first outer surface 710 side. In the first state, the second claw portion 715b contacts the second holder member 72 at the edge of the second opening 721b on the first outer surface 710 side. This prevents the length of the coil spring 73 in the second direction from becoming longer than in the first state. It also prevents the first holder member 71 from being detached from the second holder member 72. Meanwhile, in the second state, the first claw portion 715a and the second claw portion 715b are separated from the second holder member 72.

Instead of an opening, the second holder member 72 may have a recess or step that can come into contact with the claw portion. Alternatively, the first holder member 71 may have an opening, recess, or step, and the second holder member 72 may have a claw portion.

The holding surface 620 of the holder 62 can move in the second direction relative to the casing 10 due to the dimensional difference between the first through hole 451a and the first boss 621a, the dimensional difference between the second through hole 451b and the second boss 621b, the dimensional difference between the recess 15 and the third boss 621c, and the expansion and contraction of the coil spring 73.

In the following, the position of the holding surface 620 in the second direction relative to the casing 10 before the developer cartridge 1 is installed in the drawer unit 90 is referred to as the "initial position." Furthermore, when installing the developer cartridge 1 in the drawer unit 90, the position of the holding surface 620 in the second direction relative to the casing 10 at the moment when the coil spring 73 is most compressed is referred to as the "intermediate position." Furthermore, the position of the holding surface 620 in the second direction relative to the casing 10 when the electrical contact surface 611 contacts the terminal portion 913 (described below) is referred to as the "contact position." Furthermore, the position of the holding surface 620 in the second direction relative to the casing 10 after installation of the developer cartridge 1 in the drawer unit 90 is complete is referred to as the "final position."

In addition to the holding surface 620 described above, the first outer surface 710 further includes a first surface 711, a second surface 712, a third surface 713, and a fourth surface 714.

The first surface 711 is provided on one of the two sides of the holding surface 620 in the third direction, closer to the developing roller 30. The first surface 711 is inclined with respect to the electrical contact surface 611 of the IC chip 61 held on the holding surface 620.

Here, one end of the first outer surface 710 in the third direction is defined as the first outer end position 711a. Furthermore, one end of the holding surface 620 in the third direction is defined as the first inner end position 711b. As shown in FIG. 6, the first surface 711 extends from the first outer end position 711a toward the electrical contact surface 611 to the first inner end position 711b. In both the second direction and the third direction, the first outer end position 711a is farther from the electrical contact surface 611 than the first inner end position 711b. Furthermore, as shown in FIG. 6, the distance d1 in the second direction between the first outer end position 711a and the first inner end position 711b is greater than the distance d2 in the second direction between the electrical contact surface 611 and the first inner end position 711b.

The second surface 712 is provided on one of the two sides of the holding surface 620 in the third direction, the side farthest from the developing roller 30. The second surface 712 is inclined with respect to the electrical contact surface 611 of the IC chip 61 held on the holding surface 620.

Here, the other end of the first outer surface 710 in the third direction is defined as the second outer end position 712a. The other end of the holding surface 620 in the third direction is defined as the second inner end position 712b. As shown in FIG. 6, the second surface 712 extends from the second outer end position 712a toward the electrical contact surface 611 to the second inner end position 712b. In both the second and third directions, the second outer end position 712a is farther from the electrical contact surface 611 than the second inner end position 712b. Also, as shown in FIG. 6, the distance d3 in the second direction between the second outer end position 712a and the second inner end position 712b is greater than the distance d4 in the second direction between the electrical contact surface 611 and the second inner end position 712b.

The third surface 713 is provided on one of the two sides of the electrical contact surface 611 in the first direction. The fourth surface 714 is provided on the other of the two sides of the electrical contact surface 611 in the first direction. The third surface 713 and the fourth surface 714 each extend in the third direction. Furthermore, the electrical contact surface 611 is positioned more recessed toward the coil spring 73 than the third surface 713 and the fourth surface 714. In other words, in the second direction, the third surface 713 and the fourth surface 714 are farther from the coil spring 73 than the electrical contact surface 611.

The first surface 711, second surface 712, third surface 713, and fourth surface 714 may each be flat or curved. However, it is preferable that the first surface 711, second surface 712, third surface 713, and fourth surface 714 each be a smooth surface without any steps, so that the developer cartridge 1 does not get caught when inserted into the drawer unit 90.

<4. About the drawer unit>
7 is a perspective view of the drawer unit 90. As described above, the drawer unit 90 has four slots 91 into which the developer cartridges 1 can be attached. Each slot 91 has an insertion opening 910. The insertion opening 910 is located at one of the two ends of the slot 91 in the third direction, opposite the photosensitive drum 92. Each slot 91 also has a first guide plate 911 and a second guide plate 912. The first guide plate 911 and the second guide plate 912 are located at one end of each slot 91 in the first direction.

Figure 8 is a cross-sectional view of the first guide plate 911 and the second guide plate 912, perpendicular to the first direction. As shown in Figures 7 and 8, the first guide plate 911 and the second guide plate 912 are arranged facing each other with a gap in the second direction. The first guide plate 911 and the second guide plate 912 extend along the first direction and the third direction, respectively.

The first guide plate 911 has a terminal portion 913. The terminal portion 913 is an electrical contact that can come into contact with the electrical contact surface 611 of the IC chip 61. The terminal portion 913 protrudes in the second direction from the surface of the first guide plate 911 toward the second guide plate 912. The terminal portion 913 is electrically connected to the control unit 80 within the image forming apparatus 100. The terminal portion 913 is made of a material that is, for example, a conductive metal.

As shown in the enlarged view in FIG. 7 and in FIG. 8, the first guide plate 911 has a guide protrusion 914. The guide protrusion 914 is located closer to the insertion opening 910 than the terminal portion 913. The guide protrusion 914 also protrudes from the first guide plate 911 toward the second guide plate 912. The first guide plate 911 also has a first guide surface 915. In the example of FIG. 8, the inclined surface of the guide protrusion 914 on the insertion opening side serves as the first guide surface 915. Meanwhile, the second guide plate 912 has a second guide surface 916. The distance in the second direction between the first guide surface 915 and the second guide surface 916 gradually decreases as the plate approaches the photosensitive drum 92 in the third direction.

When the developer cartridge 1 is inserted into the drawer unit 90, the first outer surface 710 of the holder 62 contacts the first guide surface 915, and the second outer surface 720 of the holder 62 contacts the second guide surface 916. This changes the distance in the second direction between the first outer surface 710 and the second outer surface 720.

The first guide plate 911 also has a third guide surface 917 and a fourth guide surface 918. The third guide surface 917 and the fourth guide surface 918 position the holder 62 in the first direction when the developer cartridge 1 is inserted into the drawer unit 90. The third guide surface 917 and the fourth guide surface 918 are located closer to the insertion opening 910 than the first guide surface 915. The third guide surface 917 and the fourth guide surface 918 are spaced apart in the first direction. The distance in the first direction between the third guide surface 917 and the fourth guide surface 918 gradually decreases as they approach the first guide surface 915.

As shown in FIG. 8 , the second guide plate 912 also has a stopper surface 919. The stopper surface 919 is a surface that limits movement of the holder 62 toward the photosensitive drum 92 after the developer cartridge 1 is inserted into the drawer unit 90. The stopper surface 919 is located closer to the photosensitive drum 92 than the second guide surface 916. The stopper surface 919 also extends from the surface of the second guide plate 912 facing the first guide plate 911 toward the first guide plate 911. In the example shown in FIG. 8 , the stopper surface 919 extends diagonally in the second and third directions.

The stopper surface may be provided on at least one of the first guide plate 911 and the second guide plate 912. That is, the first guide plate 911 may have the stopper surface. In this case, the stopper surface is located closer to the photosensitive drum 92 than the terminal portion 913. The stopper surface also extends from the surface of the first guide plate 911 facing the second guide plate 912 toward the second guide plate 912.

The first guide plate 911 also has a fifth guide surface 920. The fifth guide surface 920 is a surface that limits movement of the holder 62 toward the insertion opening 910 after the developer cartridge 1 is inserted into the drawer unit 90. The fifth guide surface 920 is located between the terminal portion 913 and the first guide surface 915 in the third direction. In the example of Figure 8, the inclined surface of the guide protrusion 914 on the terminal portion 913 side serves as the fifth guide surface 920. However, it is sufficient that the fifth guide surface 920 is provided on at least one of the first guide plate 911 and the second guide plate 912.

As shown in FIG. 7, the drawer unit 90 also has multiple separation levers 93. As shown in FIG. 8, the drawer unit 90 also has multiple pressure members 94 and multiple pressing members 95. The pressure members 94 are provided on both sides of each slot 91 in the first direction. The pressing members 95 are also provided on both sides of each slot 91 in the first direction. When a developer cartridge 1 is installed in the drawer unit 90, the first columnar protrusion 46 is positioned between the pressure member 94 and the pressing member 95 on one side of the slot 91 in the first direction. The second columnar protrusion 55 is positioned between the pressure member 94 and the pressing member 95 on the other side of the slot 91 in the first direction. The pressure member 94 presses the first columnar protrusion 46 and the second columnar protrusion 55 in the third direction toward the photosensitive drum 92.

The pressing member 95 works in conjunction with the separation lever 93. During the separation operation described below, the separation lever 93 is pressed by the driving force from the image forming apparatus 100. This causes the pressing member 95 to move in the third direction toward the pressure member 94. As a result, the first columnar projection 46 and the second columnar projection 55 are each pressed by the pressing member 95. Then, the first columnar projection 46 and the second columnar projection 55 each move against the pressure of the pressure member 94. As a result, the casing 10 and developing roller 30 of the developer cartridge 1 move in the third direction.

<5. Operation when wearing>
Next, a description will be given of the operation when the developer cartridge 1 is attached to the drawer unit 90. Figures 9 to 15 are diagrams showing the state when the developer cartridge 1 is attached to one slot 91 of the drawer unit 90.

When installing the developer cartridge 1 into the slot 91, first, as shown in Figure 9, the developer cartridge 1 is positioned opposite the insertion opening 910 of the slot 91. At this time, the first outer surface 710 and the second outer surface 720 of the holder 62 are not yet in contact with the drawer unit 90. Therefore, the coil spring 73 is in the first state described above. Furthermore, the position of the holding surface 620 in the second direction relative to the casing 10 is in the initial position described above. The developer cartridge 1 is inserted into the slot 91 in the third direction, as indicated by the dashed arrow in Figure 9.

When the developer cartridge 1 is inserted into the slot 91, as shown in Figure 10, the first surface 711 of the holder 62 comes into contact with the end of the first guide plate 911 in the third direction. The first surface 711 is then pressed against the first guide plate 911, causing the holder 62 to move in the second direction. This movement of the holder 62 is relative to the casing 10. As a result, the holder 62 is positioned in the second direction between the first guide plate 911 and the second guide plate 912.

Furthermore, the holder 62 is inserted in the third direction while contacting the third guide surface 917 and the fourth guide surface 918. This positions the holder 62 in the first direction. In this manner, in this embodiment, the holder 62 is positioned in the first direction before the electrical contact surface 611 contacts the terminal portion 913. Therefore, after the electrical contact surface 611 contacts the terminal portion 913, the position of the electrical contact surface 611 relative to the terminal portion 913 is prevented from shifting in the first direction. This prevents rubbing of the electrical contact surface 611.

As shown in FIG. 11 , the first outer surface 710 of the first holder member 71 contacts the first guide plate 911. The first outer surface 710 moves in the third direction along the surface of the first guide plate 911. Furthermore, the second outer surface 720 of the second holder member 72 contacts the second guide plate 912. The second outer surface 720 moves in the third direction along the surface of the second guide plate 912. The coil spring 73 contracts in the second direction more than in the first state.

When the developer cartridge 1 is further inserted in the third direction, the first holder member 71 contacts the first guide surface 915, and the second holder member 72 contacts the second guide surface 916. This causes the first holder member 71 and the second holder member 72 to approach each other in the second direction. That is, the first outer surface 710 and the second outer surface 720 approach each other in the second direction. Therefore, the length of the coil spring 73 in the second direction gradually shortens. Eventually, as shown in Figure 12, when the third surface 713 and the fourth surface 714 of the first holder member 71 contact the top of the guide protrusion 914, the length of the coil spring 73 in the second direction becomes its shortest. In other words, the coil spring 73 reaches its shortest state, which is shorter than the second state described above. Furthermore, the position of the holding surface 620 in the second direction relative to the casing 10 becomes the intermediate position described above.

In this way, this IC chip assembly 60 allows the position of the holding surface 620 that holds the IC chip 61 to be changed in the second direction when the developer cartridge 1 is inserted into the drawer unit 90. Therefore, the developer cartridge 1 can be inserted while changing the position of the holding surface 620 in the second direction along the guide protrusion 914. Therefore, the developer cartridge 1 can be inserted into the drawer unit 90 while suppressing friction on the electrical contact surface 611 of the IC chip 61.

In particular, in the developing cartridge 1 of this embodiment, the electrical contact surface 611 of the IC chip 61 is positioned in a recessed position relative to the third surface 713 and the fourth surface 714. Therefore, in the state shown in Figure 12, the top of the guide protrusion 914 contacts only the third surface 713 and the fourth surface 714, and does not contact the electrical contact surface 611. This prevents the guide protrusion 914 from rubbing against the electrical contact surface 611.

When the developer cartridge 1 is then further inserted in the third direction, the third surface 713 and the fourth surface 714 pass by the guide protrusion 914. Then, as shown in FIG. 13, the second surface 712 comes into contact with the guide protrusion 914. As a result, the coil spring 73 expands again from its shortest state and reaches the second state described above. As a result, as shown in FIG. 14, the electrical contact surface 611 of the IC chip 61 comes into contact with the terminal portion 913. This enables the control unit 80 of the image forming apparatus 100 to at least one of read information from and write information to the IC chip 61.

The length in the second direction of the coil spring 73 in the second state is shorter than the length in the second direction of the coil spring 73 in the first state, and longer than the length in the second direction of the coil spring 73 in the shortest state. Furthermore, the relative position in the second direction of the holding surface 620 with respect to the casing 10 is the contact position described above.

In this way, the electrical contact surface 611 comes into direct contact with the terminal portion 913 after the first outer surface 710 passes over the guide protrusion 914. Therefore, after contact, the contact position of the terminal portion 913 relative to the electrical contact surface 611 is unlikely to change. This further reduces friction on the electrical contact surface 611.

The length in the second direction between the terminal portion 913 and the second guide plate 912 is shorter than the length in the second direction between the electrical contact surface 611 and the second outer surface 720 of the developer cartridge 1 before installation. Therefore, in the state shown in Figure 14, the length in the second direction of the coil spring 73 is shorter than the natural length of the coil spring 73. As a result, the elastic force (repulsive force) of the coil spring 73 presses the electrical contact surface 611 against the terminal portion 913. This allows good contact to be maintained between the electrical contact surface 611 and the terminal portion 913.

The IC chip assembly 60 is fixed in a sandwiched state between the terminal portion 913 and the second guide plate 912. Then, in this embodiment, the casing 10 is tilted in the second direction, as indicated by the dashed arrow in Figure 15. This causes the developing roller 30 to contact the photosensitive drum 92 of the drawer unit 90. At this time, the second-direction position of the holding surface 620 relative to the casing 10 changes from the contact position described above to the final position. Furthermore, the first boss 621a moves in the second direction within the first through-hole 451a. The second boss 621b moves in the second direction within the second through-hole 451b. The third boss 621c moves in the second direction within the recess 15. This prevents the holder 62 from contacting the casing 10 and the first cover 45. Therefore, vibrations are less likely to be transmitted from the drive units, such as the first gear unit 40, to the IC chip assembly 60 during printing operations in the image forming apparatus 100. This allows for better maintenance of contact between the electrical contact surface 611 and the terminal portion 913.

<6. Separation Operation>
After the developer cartridge 1 is installed, the image forming apparatus 100 can temporarily separate the developer roller 30 from the photosensitive drum 92, that is, perform a so-called "separating operation."

When the operation indicated by the dashed arrow in Figure 15 is completed, the first columnar projection 46 and the second columnar projection 55 each come into contact with the pressure member 94. The pressure member 94 presses the first columnar projection 46 and the second columnar projection 55 in a direction that brings them closer to the photosensitive drum 92. This presses the developing roller 30 against the photosensitive drum 92. In other words, the developing roller 30 and the photosensitive drum 92 are maintained in contact with each other.

Figure 16 shows the state when the separation operation is performed. During the separation operation, the separation lever 93 is pressed by the driving force from the image forming apparatus 100. This causes the pressing member 95 to move in the third direction toward the pressure member 94. As a result, the pressing member 95 located on one side in the first direction contacts the first columnar protrusion 46 and presses the first columnar protrusion 46 toward the insertion opening 910 against the pressure of the pressure member 94. Meanwhile, the pressing member 95 located on the other side in the first direction contacts the second columnar protrusion 55 and presses the first columnar protrusion 46 toward the insertion opening 910 against the pressure of the pressure member 94. As a result, the casing 10 and developing roller 30 of the developer cartridge 1 move in the third direction, as indicated by the dashed arrow in Figure 16. As a result, the developing roller 30 and the photosensitive drum 92 are separated from each other.

In both the contact state and the separated state, the IC chip assembly 60 is fixed between the terminal portion 913 and the second guide plate 912. The electrical contact surface 611 is in contact with the terminal portion 913. The holder 62 is not in contact with the casing 10 and the first cover 45. The first guide plate 911 and the second guide plate 912 are also not in contact with the casing 10 and the first cover 45. Therefore, during the separation operation, the casing 10 can be moved relative to the holder 62 while the holder 62 is fixed between the first guide plate 911 and the second guide plate 912.

That is, during the separation operation, the casing 10 and developing roller 30 move in the third direction, but the position of the IC chip assembly 60 relative to the drawer unit 90 does not change. Furthermore, the state of the coil spring 73 remains unchanged, remaining in the second state. That is, the position of the casing 10 in the third direction changes while the position of the electrical contact surface 611 relative to the drawer unit 90 remains fixed. Therefore, the electrical contact surface 611 and the terminal portion 913 remain in contact. Furthermore, friction on the electrical contact surface 611 during the separation operation is reduced.

Furthermore, even when the image forming apparatus 100 is transported with the developer cartridge 1 attached to the drawer unit 90, the electrical contact surface 611 and the terminal portion 913 remain in contact with each other. This further reduces friction on the electrical contact surface 611.

In the above embodiment, the direction in which the developing roller 30 separates from the photosensitive drum 92 during the separation operation (separation direction) was the third direction. However, the separation direction may be a direction other than the third direction. The separation direction may be any direction that intersects with the direction in which the electrical contact surface 611 and the terminal portion 913 face each other.

7. Modifications
Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. Various modifications will be described below, focusing on the differences from the above embodiment.

In the above embodiment, both the first guide surface and the second guide surface were inclined with respect to the third direction. However, one of the first guide surface and the second guide surface may extend parallel to the third direction, with only the other surface inclined with respect to the third direction. Also, in the above embodiment, both the first guide surface and the second guide surface were flat surfaces. However, one or both of the first guide surface and the second guide surface may be curved.

In the above embodiment, the boss on the holder was inserted into a through-hole on the first cover. However, it is also possible to provide a boss on the first cover and provide a through-hole or recess on the holder 62 into which the boss is inserted. Also, in the above embodiment, the boss on the holder was inserted into a recess on the casing. However, it is also possible to provide a boss on the casing and provide a through-hole or recess on the holder 62 into which the boss is inserted.

In addition, in the above embodiment, a coil spring 73 was used as the elastic member. However, other types of springs, such as leaf springs or torsion springs, may be used instead of the coil spring 73. Furthermore, the IC chip assembly does not have to have an elastic member. In other words, the IC chip assembly does not have to expand or contract in the second direction. In this case, the image forming apparatus may have a mechanism that applies an external force to the IC chip assembly to press the electrical contact surface against the terminal portion.

In the above embodiment, the developer cartridge is attached to the drawer unit. However, the developer cartridge may be attached to a drum cartridge having a photosensitive drum, rather than to the drawer unit. The drum cartridge with the developer cartridge attached may then be attached to the image forming device. The developer cartridge may also be attached directly to the main body of the image forming device, without going through the drawer unit or drum cartridge. The photosensitive drum may be provided within the main body of the image forming device.

In the above embodiment, an IC chip having an electrical contact surface was fixed to the outer surface of the holder. However, only the electrical contact surface that contacts the electrical connector may be fixed to the outer surface of the holder, and the portion of the IC chip other than the electrical contact surface may be located elsewhere in the developer cartridge. The electrical contact surface may also be an electrode separate from the storage medium such as the IC chip. The separate electrode may be, for example, an electrode for supplying power to the developer roller 30. In this case, the electrical contact surface is electrically connected to the developer roller 30 via a harness.

In addition, in the above embodiment, the multiple gears in the first gear section and the second gear section are engaged with each other through meshing of gear teeth. However, the multiple gears in the first gear section and the second gear section may also be engaged with each other through frictional force. For example, instead of multiple gear teeth, a friction member (e.g., rubber) may be provided on the outer periphery of the two gears that engage with each other.

Furthermore, in the above embodiment, when performing the separation operation, the casing is moved in the third direction relative to the holder while maintaining contact between the electrical contact surface and the terminal portion. However, for a purpose other than the separation operation, the housing may be moved in the third direction relative to the holder while maintaining contact between the electrical contact surface and the terminal portion.

Furthermore, the detailed shapes of the components that make up the image forming apparatus may differ from those shown in the drawings of this application. Furthermore, the elements that appear in the above-described embodiments and variations may be combined as appropriate, provided no contradictions arise.

1 Developer cartridge 10 Casing 11 First end surface 12 Second end surface 13 Storage chamber 20 Agitator 30 Developing roller 40 First gear portion 41 Coupling 42 Developing roller gear 43 Idle gear 44 First agitator gear 45 First cover 46 First columnar projection 50 Second gear portion 51 Second agitator gear 52 Detection gear 53 Conductive member 54 Second cover 55 Second columnar projection 60 IC chip assembly 61 IC chip 62 Holder 71 First holder member 72 Second holder member 73 Coil spring 90 Drawer unit 91 Slot 92 Photosensitive drum 93 Separation lever 94 Pressure member 95 Pressing member 100 Image forming apparatus 521 Detection projection 611 Electrical contact surface 710 First outer surface 720 Second outer surface 911 First guide plate 912 Second guide plate 913 Terminal portion 914 Guide protrusion 915 First guide surface 916 Second guide surface 917 Third guide surface 918 Fourth guide surface 919 Stopper surface 920 Fifth guide surface

Claims (11)

An image forming apparatus,
a housing capable of accommodating a developer;
a storage medium having an electrical contact surface;
a first holder that holds the storage medium and moves relative to the housing;
a second holder connected to the housing and the first holder and movable relative to the housing and the first holder;
a developing cartridge including the
an electrical contact that contacts the electrical contact surface of the developer cartridge;
Equipped with
an electrical contact surface and an electrical contact point, the electrical contact point being in contact with each other; and a housing that is movable relative to the first holder and the second holder. 2. The image forming apparatus according to claim 1,
the housing has a boss,
The image forming apparatus is characterized in that the second holder has a through hole into which the boss is inserted. 2. The image forming apparatus according to claim 1,
an image forming apparatus comprising: a stretchable elastic member positioned between the first holder and the second holder; 4. The image forming apparatus according to claim 3,
The image forming apparatus is characterized in that the elastic member is a spring. 2. The image forming apparatus according to claim 1,
The developing cartridge is
An image forming apparatus comprising a developing roller supported by the housing, the developing roller being movable between a position in contact with the photosensitive drum and a position away from the photosensitive drum while the electrical contact surface and the electrical contact are in contact. 2. The image forming apparatus according to claim 1,
The image forming apparatus is characterized in that the electrical contact is electrically connected to a circuit board. a housing capable of accommodating a developer;
a storage medium having an electrical contact surface;
a first holder that holds the storage medium and moves relative to the housing;
a second holder connected to the housing and the first holder and movable relative to the housing and the first holder;
A developing cartridge comprising:
A developing cartridge, which is attached to an image forming apparatus and characterized in that the housing is movable relative to the first holder and the second holder with the electrical contact surface in contact with an electrical contact of the image forming apparatus . 8. The developing cartridge according to claim 7,
A developing cartridge comprising: an expandable elastic member positioned between the first holder and the second holder. 9. The developing cartridge according to claim 8 ,
The developing cartridge is characterized in that the elastic member is a spring. 8. The developing cartridge according to claim 7,
the housing has a boss,
The second holder has a through hole into which the boss is inserted. 8. The developing cartridge according to claim 7,
The developing cartridge is characterized in that it has a developing roller supported by the housing, and is movable between a position in contact with the photosensitive drum and a position away from the photosensitive drum while the electrical contact surface is in contact with an electrical contact provided in the image forming device.