JP2008185971A - Image forming apparatus - Google Patents

Abstract

An access failure caused by a difference between a timing for setting a process cartridge to a predetermined position and a timing for accessing the storage medium is prevented while accessing a storage medium mounted on the process cartridge as quickly as possible.
A plurality of process cartridges having electrostatic image characteristic process mechanism members are provided, the process cartridge is provided with a storage medium, and the apparatus main body is provided with a contact for enabling connection to the storage medium. The contact point is not set until the process cartridge is set to the predetermined holding position, and the urging means for urging the process cartridge to the predetermined holding position with respect to the apparatus main body is provided in the apparatus main body or the process cartridge. In the image forming apparatus in which access to the storage medium is possible through the storage medium, the storage medium is accessed from the apparatus main body side in the order in which the plurality of process cartridges are energized.
[Selection] Figure 5

Description

  The present invention relates to an image forming apparatus such as a printer, a copying machine, a fax machine, and a scanner, and more particularly to an image forming apparatus including a process cartridge having a storage medium mounted thereon.

  2. Description of the Related Art Conventionally, in a general image forming apparatus, particularly a small so-called low-end machine, a process cartridge system in which an electrophotographic process means is detachable from an image forming apparatus main body is used. At this time, the process means is a cartridge in which at least one of a charging means, a developing means, and a cleaning means and a photoconductor as an image carrier (these are electrostatic image forming process mechanism members) are integrated into a cartridge. By adopting the process cartridge system, when the photoconductor is consumed or when the developer is consumed, the user can perform work such as replacement of the photoconductor and replenishment of the developer without relying on a professional serviceman. The operability is greatly improved.

  The life of such a process cartridge is determined by the number of uses, etc., and therefore, it is necessary to perform management by grasping the process cartridge state such as the number of uses. The process cartridge has a nonvolatile memory (RAM) as a storage medium. The amount used in the main body of the image forming apparatus is stored in this non-volatile memory, and the use limit of the process cartridge is determined based on this information, and the user is prompted to replace it. Due to these functions and purposes, the main body of the image forming apparatus accesses the non-volatile memory of the process cartridge before and after image formation and after replacement of the process cartridge. Some are configured to detect the presence or absence of a process cartridge by accessing the nonvolatile memory of the process cartridge from the image forming apparatus main body. As a storage medium, there are a magnetic storage medium and an optical storage medium in addition to a nonvolatile memory.

  In a configuration in which process cartridge status information is obtained by accessing the storage medium of the process cartridge from the main body of the apparatus, or the attachment of the process cartridge is recognized, the connection between the main body of the apparatus and the storage medium is electrically connected. In general, the contact is performed by manual contact. However, since the process cartridge system is advantageous for the user's own maintenance work, various users will mount the process cartridge, and the mounting may be incomplete.

  If the connection between the main unit and the storage medium of the process cartridge is not reliable, it will be impossible to replace the process cartridge at an appropriate timing, or even if the process cartridge is correctly installed, it will be mistakenly set as a defective set by the user. Warnings may occur, reducing the reliability of the device. Therefore, in order to ensure electrical connection between the storage medium mounted on the process cartridge and the image forming apparatus main body, thereby preventing erroneous detection when detecting the presence or absence of the process cartridge or detecting abnormality of the storage medium itself, In Patent Document 1 and Patent Document 2, stabilization of the contact of the process cartridge power feeding unit is achieved by using a driving device (for example, a gear for driving a photosensitive member is used as a contact offset means, or a helical gear is also used as a gear. As a result, a hook is formed so that the engaging portion between the process cartridge and the apparatus main body generates a thrust force on the process cartridge). Patent Document 3 proposes a configuration in which the cartridge is pressed and positioned by a pressing means that interlocks with the closing operation of the cover so that the cartridge contact and the main body contact can be moved integrally in the cartridge mounting state.

Japanese Patent No. 3311249 Japanese Patent No. 3641683 JP 2006-65267 A

  Conventionally, in an image forming apparatus having a plurality of process cartridges in which each process cartridge is provided with a storage medium, as the access timing to the storage medium, all process cartridges (each storage If the device cartridge is accessed, the process cartridge is energized by closing the device housing cover, and if the access timing to the storage medium deviates slightly earlier than the timing when it is set to the proper position, an access failure will occur. It has occurred. Such a problem can be avoided if the access timing is delayed by a considerable amount (for example, several seconds) from the process cartridge set timing. However, the access timing can be achieved as quickly as possible, while the access failure due to the timing deviation is prevented. It is requested to do. The present invention is caused by the difference between the timing for setting the process cartridge to a predetermined position and the timing for accessing the storage medium while accessing the storage medium such as a nonvolatile memory mounted on the process cartridge as quickly as possible. It is an object to prevent access failure.

  According to the present invention, there is provided an image forming apparatus having a plurality of process cartridges each including an electrostatic image characteristic process mechanism member, wherein the process cartridge is provided with a storage medium, and the image forming apparatus body includes An image forming apparatus is provided in which a contact for enabling connection with a storage medium is provided, and biasing means for biasing the process cartridge to a predetermined holding position with respect to the image forming apparatus main body is provided in the apparatus main body or the process cartridge. In the image forming apparatus in which the storage medium can be accessed through the contact point only after the process cartridge is set to a predetermined holding position, each storage from the apparatus main body side in the order in which the plurality of process cartridges are energized. It is solved by being configured to access the medium.

  The urging means is preferably provided in an apparatus main body opening cover for attaching / detaching the process cartridge. The opening cover is a cover that rotates about the rotation axis, and is effective if it is biased from a process cartridge close to the rotation axis.

  It is advantageous if a drive transmission member interconnecting the process cartridge and the apparatus main body is provided, and the storage medium is accessed before the drive transmission member is driven. It is also assumed that the drive transmission member is made of a gear, and in such a case, a sufficient urging force is required to ensure that both the drive transmission members are engaged with each other so that they can be engaged even if there is tooth tip interference. The urging means is required to be provided.

  It is preferable to provide a detecting means for detecting that the process cartridge is energized. One detection means may be provided for a plurality of process cartridges, or may be provided for each process cartridge.

  The detection means is configured to detect an energization of the process cartridge by closing a cover that is an apparatus main body opening cover for attaching and detaching the process cartridge and that rotates around the rotation axis. Good. When only one detection means is provided, the detection means is preferably provided in the vicinity of the process cartridge far from the rotation axis of the cover.

  It is preferable that the access is performed again when the access to the storage medium is unsuccessful. A transfer device having means for moving the transfer member to and away from the photosensitive member, which is one of the electrostatic image characteristic process mechanism members, and accessing the storage medium before the transfer member contacts the photosensitive member; It is preferred that The process cartridge may be attached or detached in the vertical direction.

  According to the first aspect of the present invention, the storage medium can be accessed through the contact only after the process cartridge is set to a predetermined holding position, and the plurality of process cartridges are energized in the order in which they are energized. Since it is configured to access each storage medium from the main body side, it is possible to prevent an access failure caused by a deviation between the timing at which the process cartridge is energized and set at a normal position and the access timing to the storage medium.

  According to a second aspect of the present invention, if the urging means is provided in an apparatus body opening cover for attaching and detaching the process cartridge, the cartridge is urged simultaneously with the operation of closing the cover. Therefore, user operation is easy. According to a third aspect of the present invention, the opening cover is a cover that rotates about the rotation axis. If the opening cover is biased from a process cartridge that is close to the rotation axis, the rotation track of the cover is used. The storage medium can be easily accessed from the apparatus main body side in the order in which the plurality of process cartridges are energized.

  According to a fourth aspect of the present invention, there is provided a drive transmission member interconnected to each of the process cartridge and the apparatus main body, and if the storage medium is accessed before the drive transmission member is driven, it is determined whether or not the process cartridge can be used. Can be advanced by the drive rotation time, and the time until the image forming process can be shortened by the drive rotation time. In addition, troubles such as damage to the device caused by driving rotation can be avoided.

  According to a fifth aspect of the present invention, by providing a detection means for detecting that the process cartridge is energized, access is performed after detection, and the access timing is managed at an arbitrary time. Can do. Further, since the energization of the cartridge is directly detected, the time from the energization of the cartridge to the access can be shortened, or it can be managed at an arbitrary time. As described in claim 6, if only one detection means is provided for a plurality of process cartridges, the cost can be reduced. According to a seventh aspect of the present invention, when the apparatus main body opening cover for attaching and detaching the process cartridge is closed to detect the urging of the process cartridge, the detection means simultaneously with the operation of closing the cover. Since the cartridge urging and the urging detection operation are performed, the user operation is simple. If the opening cover is a cover that rotates about the rotation axis and the detection means is provided in the vicinity of the process cartridge that is far from the rotation axis of the cover, Shift in detection timing is unlikely to occur. If the detection means is provided for each process cartridge as in claim 9, the operation from cartridge energization to access is reliably performed, and the process cartridge detected earlier is quickly accessed. Will be able to. As described in claim 11, when an access failure occurs, the access failure can be recovered by performing the access again. If access failure occurs again, it is determined that the corresponding process cartridge cannot be stored in the predetermined holding position for some reason, and the output image cannot be guaranteed even if the image forming operation is performed, and the user is notified. Stop the device drive. According to a thirteenth aspect of the present invention, in the case where a transfer member that can be contacted and separated is provided, access to the storage medium is performed before the transfer member comes into contact with the photosensitive member, so that useless transfer when an access failure occurs It is not necessary to perform the contact operation of the member. Access failures that may occur due to the process cartridge floating due to the transfer roller contact pressure can be avoided by setting the biasing force of the biasing means higher than the transfer roller contact pressure.

Embodiments of the present invention will be described below.
FIG. 1 shows an overall configuration of a color laser printer 1 which is an embodiment of an image forming apparatus according to the present invention. As shown in FIG. 1, the printer 1 includes photosensitive drums 21K, 21C, 21M, 21Y, which rotate at a constant speed for each color of black (K), cyan (C), magenta (M), and yellow (Y). Development cartridges 22K, 22C, 22M, and 22Y as developer carriers, toner storage containers 23K, 23C, 23M, and 23Y, and other process cartridges 2K, 2C, and 2M that are configured integrally with an electrophotographic process. 2Y, an exposure device 3 for writing image information on the photosensitive drum, an intermediate transfer member 4 (intermediate transfer belt [transfer material] that holds the color image developed and transferred on the photosensitive drums 21K, 21C, 21M, and 21Y. P is also a conveying belt of P] 41, and is composed of a driving roller 42 that transmits drive, and a tension roller 43 that stretches an intermediate transfer belt), To the final transfer position of the intermediate transfer member 4 and a feeding device 5 for supplying the transfer material P from the paper feed cassette 51. In addition, a fixing device 6 that fixes the color image transferred onto the transfer material P to which the color image has been transferred, and a discharge roller 71 that discharges the transfer material 5 after image fixing to a paper discharge portion on the upper surface of the apparatus housing. A paper unit 7, a transport device 8 for transporting the transfer material P fed from the paper feed device 5, and a duplex printing mechanism 9 for forming images on both sides of the transfer material P are provided.

Next, the configuration of each part of the printer 1 will be described in detail.
The process cartridge shown in FIG. 2 (K, C, M, and Y indicating colors are omitted for simplification) includes the photosensitive drum 21, the developing roller 22, the toner container 23, and the like as described above. A charging unit 24 for uniformly charging the surface of the photosensitive drum 21 and an image carrier cleaning mechanism 25 are integrally configured. A drive transmission mechanism (for example, a helical gear) (not shown) (described later) coaxially with the photosensitive drum 21 is rotated by obtaining power from a drive device (not shown). After the surface of the photosensitive drum 21 is uniformly charged by the charging unit 24, an electrostatic latent image is formed on the photosensitive drum by each color LD light 31 from the exposure device 3. Further, the electrostatic latent image is visualized by the developing roller 22 and becomes a visible image with toner of each color of black, cyan, magenta, and yellow for each cartridge. The intermediate transfer belt 41 is rotated to multiplex-transfer the toner image of the photosensitive drum 21 visualized by each process cartridge during the image forming operation, and the toner image formed on the photosensitive drum 21 is transferred. At this time, the transfer belt 41 brings the transfer roller 44 into contact with the photosensitive drum 21 via the transfer belt 41 by a contact / separation mechanism (not shown). When the image is not transferred, it is separated to suppress wear. The intermediate transfer belt 41 that has received the multiple transfer transfers the color toner image onto the transfer material P at the final transfer position.

Next, an example of the configuration around the process cartridge, which is the center of the present invention, and the operation at the time of replacement will be described.
As shown in FIGS. 3, 4, and 5, in this example, the cover 101 that constitutes a part of the housing of the printer 1 rotates around the pivot point 102, and the opening 101 is formed by lifting the cover 101. The process cartridge 2 can be attached and detached. A biasing member 103 for biasing the process cartridge 2 is attached to the cover 101 at the bottom of the exposure apparatus 3 (FIG. 4). In this example, a coil spring is used as the biasing member 103, but a rigid member having no spring property may be used. However, a spring having a spring property such as a coil spring is advantageous in that the operation force can be adjusted. It is also possible to provide an urging member on the process cartridge side. After the process cartridge 2 is inserted into the printer 1, the cover 101 is closed again, so that an urging force is applied to the process cartridge 2 and the process cartridge 2 can be correctly pushed into a normal position (holding position) (FIG. 5). At this time, the normal position indicates a state where the shaft 27 arranged concentrically with the photosensitive drum 21 of the process cartridge 2 is in a position where it abuts the positioning portion A of the printer main body, as shown in FIG. Therefore, the state where the process cartridge is “not in the proper position” indicates “a state where the process cartridge is not urged or a state where the process is being urged”. In this example, a detecting means 104 for detecting that the process cartridge 2 is energized is provided. Thus, after the process cartridge 2 is urged to the proper position, the printer 1 can store the storage medium 26 (nonvolatile memory, magnetic memory, photo memory) mounted on the process cartridge 2 via the contact terminal 105 (FIG. 7). ) Can be accessed. The timing to access after detection is preferably before the photosensitive drum 21 is driven in order to promptly warn the replacement from the viewpoint of ensuring the output image and protecting the apparatus when the process cartridge 2 is abnormal. At this time, if the process cartridge 2 is not in the proper position, the storage medium 26 and the contact terminal 105 on the printer main body side cause a contact failure, resulting in an access failure. Factors that cause the process cartridge 2 not to be in the proper position include interference of tooth tips at the connecting portion between the drive gear 106 and the photosensitive member drive gear 28 as shown in FIG. 7, and contact of the transfer roller 44 as shown in FIG. It is conceivable that the process cartridge floats in the attaching / detaching direction due to the pressure.

  In the modification shown in FIGS. 9 and 10, a biasing member 103 for biasing the process cartridge 2 is attached to the printer cover 101 that rotates about the shaft fulcrum 102, and the process cartridge near the shaft fulcrum is biased. In consideration of this point, instead of the plurality of detecting means 104 as shown in FIG. 4, only one detecting means 104a is arranged between the process cartridges. Even the only detection means 104a can detect the urging means by closing the cover 101. According to the order in which the plurality of process cartridges 2 are energized, the printer 1 can access the storage medium 26 mounted on the process cartridge 2 via the contact terminals 105.

  When the detection means is set at the position 104a shown in FIGS. 9 and 10 due to layout restrictions, or when the detection means is detected by the operation of the urging means as shown in FIG. Since the detecting means may act before the process cartridge far from 102 is energized, access to the storage medium 26 of the process cartridge far from the pivot point 102 that is not in the proper position will cause an access failure. On the other hand, in the present invention in which the storage medium 26 is accessed in the order in which the process cartridge is energized, that is, in this example, from the process cartridge closer to the rotation shaft fulcrum 102, the rotation shaft fulcrum is activated after the detection means 104a is activated. Until the process cartridge far from 102 is energized, the access is made to the storage medium 26 of the process cartridge near the energized rotating shaft fulcrum 102, so that an access failure can be prevented. At this time, as the arrangement position of the detection means, as shown in FIG. 12, it is more effective to place the detection means 104b near the process cartridge farthest from the pivot point 102 of the cover 101.

  In the above embodiment, the cover is rotated and opened, and the process cartridge is attached to and detached from the process main body. However, the process cartridge is not rotated as shown in FIG. 13 or the process cartridge is attached from the front of the main body as shown in FIG. The same effect can be obtained in the detachable image forming apparatus by using the configuration of the present invention.

1 is a schematic configuration diagram of an image forming apparatus according to the present invention. It is a schematic block diagram of a process cartridge. FIG. 2 is a diagram illustrating how a process cartridge is attached to and detached from the image forming apparatus in FIG. 1. It is a figure explaining the attachment position of a biasing member. It is a figure which shows the state which urges | biases a process cartridge with an urging | biasing member. It is a figure explaining a mode that a detection means act | operates by a biasing member when a process cartridge is mounted in a regular position. FIG. 6 is a diagram illustrating a state in which a storage medium cannot be accessed due to tooth tip interference at a connecting portion between the drive gear and the photosensitive member drive gear. It is a figure explaining a mode that a process cartridge floats in the attachment or detachment direction by the transfer roller contact pressure. It is a figure explaining arrangement | positioning in case a detection means is one. FIG. 10 is a diagram illustrating a state in which the process cartridge is urged by the urging member in the configuration of FIG. 9. It is a figure in case a detection means is arrange | positioned in the position away from the biasing member by the relationship of the layout. It is a figure which shows the example which puts a detection means near the process cartridge furthest from the rotating shaft fulcrum of a cover. It is a figure which shows the structure which removes without rotating a main body cover. It is a figure which shows a mode that a process cartridge is attached or detached from the main body front.

Explanation of symbols

2 Process cartridge 21 Photoconductor 22 Developing roller 23 Toner container 24 Charging means 25 Image carrier cleaning mechanism 31 LD light 41 Transfer belt 44 Transfer roller

Claims (12)

An image forming apparatus having a plurality of process cartridges each including an electrostatic image characteristic process mechanism member, wherein the process cartridge is provided with a storage medium, and the image forming apparatus body can be connected to the storage medium. The image forming apparatus is provided with a contact, and an urging means for urging the process cartridge to a predetermined holding position with respect to the image forming apparatus main body is provided in the apparatus main body or the process cartridge, and the process cartridge holds the predetermined holding In the image forming apparatus in which the storage medium can be accessed through the contact point only after being set to the position.
An image forming apparatus configured to access each storage medium from the apparatus main body in the order in which the plurality of process cartridges are energized.   The image forming apparatus according to claim 1, wherein the urging unit is provided in an apparatus main body opening cover for attaching and detaching the process cartridge.   The image forming apparatus according to claim 1, wherein the opening cover is a cover that rotates about a rotation axis, and is biased from a process cartridge that is close to the rotation axis.   4. A drive transmission member interconnected to each of the process cartridge and the apparatus main body is provided, and the storage medium is accessed before the drive transmission member is driven. The image forming apparatus described in 1.   The image forming apparatus according to claim 1, further comprising a detection unit configured to detect that the process cartridge is energized.   6. The image forming apparatus according to claim 5, wherein only one detection unit is provided for a plurality of process cartridges.   The image forming apparatus according to claim 5, wherein the detection unit is capable of detecting the process cartridge urging by closing an apparatus main body opening cover for attaching and detaching the process cartridge.   8. The image forming apparatus according to claim 7, wherein the opening cover is a cover that rotates about a rotation axis, and the detection unit is provided in the vicinity of a process cartridge far from the rotation axis of the cover. apparatus.   The image forming apparatus according to claim 5, wherein the detection unit is provided for each process cartridge.   A drive transmission member interconnected to each of the process cartridge and the apparatus main body is provided, and the biasing means has a biasing force sufficient for the two drive transmission members to be engaged with each other. The image forming apparatus according to claim 1.   The image forming apparatus according to claim 1, wherein the image forming apparatus is configured to perform access again when at least one access to the storage medium is unsuccessful.   A transfer device having means for moving the transfer member to and away from the photosensitive member, which is one of the electrostatic image characteristic process mechanism members, and accessing the storage medium before the transfer member contacts the photosensitive member; The image forming apparatus according to claim 1.

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