JP2005321580A - Process cartridge and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a process cartridge and an image forming apparatus constituted so that an operation of attaching/detaching a process cartridge to/from the image forming apparatus main body and an operation of positioning the process cartridge in the image forming apparatus body and an operation related to the release, can interlock, and then, a user can perform the attaching/detaching operation without a feeling of incompatibility. <P>SOLUTION: The process cartridge 4 is provided with a grip part 26 used for the attaching/detaching operation to/from the image forming apparatus main body 2, an engagement part 22 constituted so as to be engaged with a positioning member 11 arranged in the image forming apparatus main body 2, and a releasing member 24 constituted so as to release the engagement of the engagement part 22 with the positioning member 11. In detaching the process cartridge from the image forming apparatus main body 2, the engagement of the engagement part 22 with the positioning member 11 is released by the releasing member 24 cooperatively with an operation of grasping the releasing member 24 together with the grip part 26. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus using an electrophotographic system such as a copying machine, a printer, a facsimile, or a multifunction machine thereof, and a process cartridge that is detachably installed therein.

  Conventionally, in an image forming apparatus such as a laser printer, an image forming member such as a photosensitive drum (image carrier), a charging unit, a developing unit, a cleaning unit, etc. for the purpose of improving the workability of maintenance by the user himself / herself A process cartridge that is integrated into the image forming apparatus main body so as to be replaceable is widely used (see, for example, Patent Document 1).

The process cartridge installed in the main body of the image forming apparatus reaches the end of its life as the photosensitive drum, developer, etc. provided in the cartridge deteriorate or the toner is completely consumed with the subsequent operation. Then, the process cartridge that has reached the end of its life is taken out from the main body of the image forming apparatus by the user. A new process cartridge is newly installed in the apparatus main body by the user.
As described above, since the process cartridge is often replaced by the user, first, high detachability with respect to the image forming apparatus main body is required.

  On the other hand, the image forming process in the image forming apparatus is performed by an exposure unit and a transfer unit fixed to the apparatus main body, and each image forming member provided in the process cartridge. That is, the exposure light emitted from the exposure unit of the apparatus main body is irradiated onto the photosensitive drum of the process cartridge, and an electrostatic latent image is formed at a desired position on the photosensitive drum (exposure process). ). Further, the toner image formed on the photosensitive drum of the process cartridge is transferred to a desired position on the recording medium by the transfer unit of the apparatus main body (this is a transfer process).

  Accordingly, when the position accuracy of the process cartridge in the image forming apparatus main body is poor, the electrostatic latent image formed on the photosensitive drum is displaced from the desired position, or the toner image transferred onto the recording medium is displaced from the desired position. Thus, a desired output image cannot be obtained. Therefore, in an image forming apparatus provided with a process cartridge, secondly, it is required to accurately position the process cartridge at a desired position in the image forming apparatus main body.

  On the other hand, in Patent Document 1, etc., shaft portions are provided on both sides of the longitudinal direction of the process cartridge (the direction perpendicular to the attaching / detaching direction), and these shaft portions are engaged with recesses provided in the apparatus main body. A technique for positioning the process cartridge in the apparatus main body is disclosed.

JP 2003-208075 A

  The above-described conventional technology does not provide a sense of unity between the operation of attaching / detaching the process cartridge to / from the main body of the image forming apparatus and the operation related to the positioning and release of the process cartridge in the main body of the image forming apparatus, and may give the user a sense of incompatibility. there were.

That is, at the time of mounting the process cartridge, it is difficult for the user to realize how far the process cartridge is inserted to complete the mounting operation and position the process cartridge in the apparatus main body.
Further, at the time of the process cartridge detachment operation, the user does not know how much force can be pulled out with respect to the process cartridge positioned in the apparatus main body.

  As described above, there are cases where the user performs the attaching / detaching operation while feeling uneasy about the mounting failure or damage of the process cartridge. This is because the attachment / detachment operation and the positioning / release thereof are not completely linked, and the operations are difficult to understand.

  The present invention has been made to solve the above-described problems, and the attachment / detachment operation of the process cartridge with respect to the main body of the image forming apparatus and the operation related to the positioning and release of the process cartridge in the main body of the image forming apparatus are interlocked. Thus, it is an object of the present invention to provide a process cartridge and an image forming apparatus that allow a user to perform an attaching / detaching operation without feeling uncomfortable.

  A process cartridge according to a first aspect of the present invention is a process cartridge that is detachably installed in an image forming apparatus main body, a grip portion for performing an attaching / detaching operation to the image forming apparatus main body, and the image cartridge An engagement portion configured to be engageable with a positioning member provided in the forming apparatus main body, and a release member configured to be able to release engagement between the engagement portion and the positioning member, The releasing member is configured to release the engagement between the engaging portion and the positioning member in conjunction with an operation of being held together with the holding portion when performing a detachment operation from the image forming apparatus main body. Is.

  A process cartridge according to a second aspect of the present invention is the process cartridge according to the first aspect, wherein the release member is gripped together with the gripping portion when performing an attaching / detaching operation to the image forming apparatus main body. It is comprised as follows.

  The process cartridge according to a third aspect of the present invention is the process cartridge according to the first or second aspect, wherein the engaging portion is interlocked with a mounting operation to the image forming apparatus main body. It is comprised so that it may engage with.

  A process cartridge according to a fourth aspect of the present invention is the process cartridge according to any one of the first to third aspects, wherein the release member is a release lever supported so as to be swingable. The positioning member is a lock lever that is swingably supported by the image forming apparatus main body, and the engagement portion is engaged with the distal end portion of the lock lever, and one end of the release lever is provided in the vicinity. It is a hole.

  The process cartridge according to a fifth aspect of the present invention is the process cartridge according to the fourth aspect, wherein the release lever swings and the one end of the release lever abuts on the tip of the lock lever. When the lock lever swings, the engagement between the hole and the lock lever is released.

  The process cartridge according to a sixth aspect of the present invention is the process cartridge according to the fourth or fifth aspect, wherein the other end of the release lever via the swing center is gripped together with the grip portion. It is comprised so that it may be.

  A process cartridge according to a seventh aspect of the present invention is the process cartridge according to any one of the first to sixth aspects, wherein the urging member that urges the release member in a direction close to the gripping portion. It is provided.

  A process cartridge according to an eighth aspect of the present invention is the process cartridge according to the seventh aspect, wherein the biasing member is a torsion coil spring.

  An image forming apparatus according to a ninth aspect of the present invention includes the process cartridge according to any one of the first to eighth aspects, the main body of the image forming apparatus, and the positioning member. .

  In the present application, “process cartridge” means a charging unit (charging unit) for charging an image carrier, a developing unit (developing unit) for developing a latent image formed on the image carrier, and an image carrier. It is defined as a unit in which at least one of the cleaning means (cleaning unit) for cleaning the top and the image carrier are integrated and installed detachably with respect to the image forming apparatus main body.

  The present invention is configured such that an operation for attaching / detaching a process cartridge to / from the image forming apparatus main body and an operation related to positioning and releasing of the process cartridge in the image forming apparatus main body are interlocked. As a result, it is possible to provide a process cartridge and an image forming apparatus that allow a user to perform an attaching / detaching operation without a sense of incongruity.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the part which is the same or it corresponds, The duplication description is simplified or abbreviate | omitted suitably.

Embodiment 1 FIG.
The first embodiment of the present invention will be described in detail with reference to FIGS.
First, the configuration and operation of the entire image forming apparatus will be described with reference to FIG.
In FIG. 1, 1 is a main body of a laser printer as an image forming apparatus, 3 is an exposure unit that irradiates a photosensitive drum 18 with exposure light L based on image information, and 4 is detachably installed on the apparatus main body 1. 7 is a transfer unit that transfers the toner image formed on the photosensitive drum 18 to the recording medium P, 9 is a fixing unit that fixes an unfixed image on the recording medium P, and 10 is an output image. A paper discharge tray, 12 is a paper feed unit storing a recording medium P such as transfer paper, 13 is a registration roller for conveying the recording medium P to the transfer unit 7, and 15 is opened and closed when the process cartridge 4 is attached / detached. Show the door.

With reference to FIG. 1, an operation during normal image formation in the image forming apparatus will be described.
First, exposure light L such as laser light based on image information is emitted from the exposure unit 3 (writing unit) toward the photosensitive drum 18 of the process cartridge 4. The photoconductive drum 18 rotates in the clockwise direction in the drawing, and corresponds to image information on the photoconductive drum 18 through a predetermined image forming process (charging process, exposure process, developing process, cleaning process, charge eliminating process). A toner image is formed.
Thereafter, the toner image formed on the photosensitive drum 18 is transferred onto the recording medium P conveyed by the registration roller 13 in the transfer unit 7.

On the other hand, the recording medium P conveyed to the transfer unit 7 operates as follows.
First, the uppermost sheet of the recording medium P stored in the paper feeding unit 12 is transported toward the position of the transport path K. Thereafter, the recording medium P passes through the conveyance path K and reaches the position of the registration roller 13. Then, the recording medium P that has reached the position of the registration roller 13 is conveyed toward the transfer unit 7 at the same timing in order to align with the toner image formed on the photosensitive drum 18.

Then, the recording medium P after the transfer process passes through the position of the transfer unit 7 and then reaches the fixing unit 9 through the conveyance path. The recording medium P that has reached the fixing unit 9 is fed between the fixing roller and the pressure roller, and the toner image is fixed by heat received from the fixing roller and pressure received from both rollers. Thereafter, the recording medium P on which the toner image is fixed is discharged from the image forming apparatus main body 1 as an output image and placed on the paper discharge tray 10.
Thus, a series of image forming processes is completed.

Next, referring to FIG. 2, the configuration and operation of the image forming unit centering on the process cartridge 4 installed in the image forming apparatus main body 1 will be described in detail.
As shown in FIG. 2, the process cartridge 4 mainly includes a photosensitive drum 18 as an image carrier, a charging unit 19 (charging unit), a developing unit 20 (developing unit), and a cleaning unit 21 (cleaning unit). Are integrated with each other and are detachable from the image forming apparatus main body 1.

The photosensitive drum 18 is formed by forming a charge generation layer, a charge transport layer, and the like on a base tube made of aluminum.
The charging unit 19 is formed by forming a roller unit made of a conductive material in which conductive powder is dispersed in a resin on a shaft formed of stainless steel.
The cleaning unit 21 is provided with a cleaning blade 21 a made of a rubber material and cleaning the untransferred toner in contact with the photosensitive drum 18.

  The developing unit 20 mainly includes a developing roller 20a facing the photosensitive drum 18, a replenishing roller 20b that is in sliding contact with the developing roller 20a, and a stirring member that stirs and conveys toner T (one-component developer) in the developing unit 20. 20c, a doctor blade 20d in contact with the developing roller 20a, and a toner storage portion 20f that supplies toner stored by the toner supply roller 20e.

Hereinafter, the image forming process performed on the photosensitive drum 18 of the process cartridge 4 will be described in detail with reference to FIG.
The photosensitive drum 18 is rotationally driven in the clockwise direction in FIG. The surface of the photosensitive drum 18 is charged to a desired charging potential at a position where the photosensitive drum 18 faces the charging unit 19 (charging process).

Thereafter, the surface of the charged photosensitive drum 18 reaches the irradiation position of the exposure light L. Then, a desired electrostatic latent image corresponding to the image information is formed on the photosensitive drum 18 while being exposed in the scanning direction of the exposure light L (the direction perpendicular to the paper surface).
Thereafter, the surface of the photosensitive drum 18 on which the latent image is formed reaches a position facing the developing unit 20. The developing unit 20 develops the latent image on the photosensitive drum 18 to form a desired toner image.

Here, the developing roller 20a rotates in the direction of the arrow in FIG. The toner T in the developing unit 20 is stirred and conveyed by the stirring member 20c and reaches the position of the replenishing roller 20b. The toner T that has reached the position of the replenishing roller 20b is conveyed to a contact portion with the developing roller 20a, and is frictionally charged there. The toner T that is frictionally charged and carried on the developing roller 20a is thinned at the position of the doctor blade 20d, and then reaches a position facing the photosensitive drum 18. Then, the toner T on the developing roller 20a adheres to the latent image on the photosensitive drum 18.
The toner T stored in the toner storage unit 20f is appropriately supplied into the developing unit 20 by the rotation of the toner supply roller 20e as the toner T in the developing unit 20 is consumed.

  Thereafter, the surface of the photosensitive drum 18 on which the toner image is formed reaches a position facing the transfer unit 7 installed in the apparatus main body 1. Then, the toner image on the photosensitive drum 18 is transferred onto the recording medium P conveyed to the position of the transfer unit 7. At this time, a small amount of untransferred toner that has not been transferred to the recording medium P remains on the photosensitive drum 18.

Thereafter, the surface of the photosensitive drum 18 to which the untransferred toner is attached reaches the position of the cleaning blade 21a. Then, the untransferred toner on the photosensitive drum 18 is removed from the drum surface by the cleaning blade 21a that is in contact with the photosensitive drum 18. Untransferred toner removed from the surface of the photosensitive drum 18 is collected in a collection space of the cleaning unit 21. Thereafter, the surface of the photosensitive drum 18 reaches the irradiation position of the static elimination light emitted from the static elimination unit (not shown). Then, the surface potential on the photosensitive drum 18 is initialized while receiving the static elimination light.
Thus, a series of image forming processes performed on the photosensitive drum 18 is completed.

The process cartridge 4 configured and operating as described above is attached to and detached from the apparatus main body 1 as follows. First, the mounting operation of the process cartridge 4 will be described.
When the process cartridge 4 is attached to the apparatus main body 1, first, the door 15 of the apparatus main body 1 shown in FIG. Thereby, the accommodating part 2 in the apparatus main body 1 is exposed. Next, referring to FIG. 3 and FIG. 4, the process cartridge 4 is slid into the opened storage portion 2 (the movement in the direction of the arrow in FIG. 4).

Here, FIG. 3 is a perspective view showing a state in which the mounting operation of the process cartridge 4 is performed. 4 is a cross-sectional view of the vicinity of the release lever 24 of the process cartridge 4 of FIG.
As shown in FIGS. 3 and 4, on the back side of the process cartridge 4 (on the developing unit 20 side in FIG. 2), both ends in the longitudinal direction are gripped by the user when performing attachment / detachment operations. A portion 26 is provided. The grip portion 26 is lower in height than the center in the longitudinal direction and has a shape that is easy for the user to grip.

  A release lever 24 as a release member is provided above the grip portion 26. The release lever 24 is supported by the cartridge 4 so as to swing in the vertical direction in FIG. 4 with the shaft portion 25 as the swing center. A contact portion 24a is provided at one end of the release lever 24, and a bent portion 24b is provided at the other end.

The contact portion 24 a of the release lever 24 is disposed at a position close to the hole 22 as an engaging portion provided in the process cartridge 4. And the contact part 24a will contact | abut the front-end | tip part 11a of the lock lever 11 mentioned later.
On the other hand, the bent portion 24b of the release lever 24 is located close to the grip portion 26 and is disposed so that the user can easily grip it. Thus, the user grips the bent portion 24b of the release lever 24 together with the grip portion 26 when the process cartridge 4 is attached or detached.

  On the other hand, in the housing portion 2 of the image forming apparatus main body 1, lock levers 11 as positioning members are installed at both ends in the longitudinal direction. The two lock levers 11 are supported by the apparatus main body 1 so as to swing in the vertical direction in FIG. 4 with the shaft portion 12 as the swing center. One end of the lock lever 11 is provided with a pointed tip portion 11a. A distal end portion 11 a of the lock lever 11 protrudes into the housing portion 2 through an opening 2 a provided in the housing portion 2. Although not shown, the lock lever 11 is provided with a biasing member (for example, a torsion coil spring) that biases the lock lever 11 in the clockwise direction in FIG. .

Thereafter, when the mounting operation of the process cartridge 4 shown in FIGS. 3 and 4 proceeds, the mounting operation of the process cartridge 4 to the apparatus main body 1 is completed.
Specifically, referring to FIGS. 5 and 6, the tip end portion 11 a of the lock lever 11 protruding into the housing portion 2 through the opening 2 a engages with the hole 22 of the process cartridge 4. As a result, the position of the process cartridge 4 in the container 2 is determined. Further, the tip end portion 11 a of the lock lever 11 contacts the contact portion 24 a of the release lever 24 of the process cartridge 4. As a result, the release lever 24 swings about the shaft portion 25 (movement in the direction of the arrow in FIG. 6). Here, the force of the biasing member that biases the lock lever 11 described above is sufficient to swing the release lever 24.

  As described above, in the mounting operation of the process cartridge 4, the user can obtain a click feeling due to the engagement between the lock lever 11 and the hole 22, and visually raise the release lever 24 (swing). Since it can be confirmed, the completion of the mounting operation with positioning can be realized without anxiety. That is, in the mounting operation of the process cartridge 4, the positioning to the apparatus main body 1 is performed smoothly without a sense of incongruity.

Next, an operation for detaching the process cartridge 4 from the apparatus main body 1 will be described with reference to FIGS.
When the process cartridge 4 is detached from the apparatus main body 1, first, the door 15 of the apparatus main body 1 shown in FIG. Thereby, the accommodating part 2 which set the process cartridge 4 is exposed.

  Next, the bent portion 24b of the release lever 24 moving upward and the grip portion 26 in the process cartridge 4 with the back surface exposed are gripped. As a result, as shown in FIGS. 7 and 8, the release lever 24 swings around the shaft portion 25 (the movement in the clockwise direction indicated by the arrow in FIG. 8) and approaches the gripping portion 26. . Further, the distal end portion 11a of the lock lever 11 is pushed up by the contact portion 24a of the release lever 24 (the movement in the counterclockwise direction indicated by the arrow in FIG. 8), and the engagement with the hole 22 is released. . Here, in the release lever 24, the distance from the shaft portion 25 to the bent portion 24b is set sufficiently longer than the distance from the shaft portion 25 to the contact portion 24a. The force for releasing the engagement is appropriate for the user.

  Thereafter, the user slides the process cartridge 4 while holding the grip portion 26 and the bent portion 24b of the release lever 24 (moving in the right direction in FIG. 8). In this way, the detachment operation with the positioning release of the process cartridge 4 is completed.

  As described above, in the process of detaching the process cartridge 4, the user visually confirms the release lever 24 rising in the vicinity of the grip portion 26 and grips the release lever 24 together with the grip portion 26. At this time, the engagement between the lock lever 11 and the hole 22 is released in conjunction with the operation of gripping the grip portion 26 and the release lever 24. That is, in the separation operation of the process cartridge 4, the positioning in the apparatus main body 1 is smoothly released with a sense of unity.

  As described above, according to the configuration of the first embodiment, the attachment / detachment operation of the process cartridge 4 with respect to the apparatus main body 1 and the operations related to the positioning and release of the process cartridge 4 in the apparatus main body 1 are interlocked. The user can perform the attaching / detaching operation without a sense of incongruity.

  In the first embodiment, the process cartridge 4 is configured such that the photosensitive drum 18, the charging unit 19, the developing unit 20, and the cleaning unit 21 are integrated. In contrast, the process cartridge 4 may be configured such that one or two of the charging unit 19, the developing unit 20, and the cleaning unit 21 and the photosensitive drum 18 are integrated.

Embodiment 2. FIG.
A second embodiment of the present invention will be described in detail with reference to FIG.
FIG. 9 is a cross-sectional view showing the image forming apparatus according to the second embodiment, and corresponds to FIG. 8 in the first embodiment. The second embodiment is different from the first embodiment in that a torsion coil spring 28 for urging the release lever 24 of the process cartridge 4 is installed.

As shown in FIG. 9, a torsion coil spring 28 as an urging member is installed on the shaft portion 25 that supports the release lever 24 of the process cartridge 4. The torsion coil spring 28 has one leg hooked to the bent part 24 b side and the other leg abutting against the inner wall of the cartridge 4. Thereby, the torsion coil spring 28 biases the release lever 24 in a direction in which the bent portion 24b of the release lever 24 approaches the grip portion 26.
Here, the force of the biasing member that biases the lock lever 11 described in the first embodiment is sufficient to swing the release lever 24 on which the torsion coil spring 28 is installed.

  As described above, in the second embodiment, the biasing force of the torsion coil spring 28 always applies a force to the release lever 24 in the direction in which the release lever 24 is close to the grip portion 26. Therefore, during the attaching / detaching operation described in the first embodiment. The operation of the release lever 24 is ensured. That is, during the mounting operation, if the lock lever 11 is not securely engaged with the hole 22, the bent portion 24b of the release lever 24 will not rise. Further, during the disengagement operation, the operability of releasing the engagement of the lock lever 11 and the hole 22 by the release lever 24 is improved.

As described above, also in the configuration of the second embodiment, as in the first embodiment, the process cartridge 4 is attached to and detached from the apparatus main body 1, and the positioning and release of the process cartridge 4 in the apparatus main body 1 are performed. In conjunction with the related operation, the user can perform the attaching / detaching operation without a sense of incongruity.
Note that the urging member in the second embodiment is not limited to the torsion coil spring 28. For example, the release lever 24 can be urged toward the grip portion 26 by using a tension spring, a compression spring, a leaf spring, or the like.

  It should be noted that the present invention is not limited to the above-described embodiments, and within the scope of the technical idea of the present invention, the embodiments can be modified as appropriate in addition to those suggested in the above-described embodiments. it is obvious. Further, the number, position, shape, and the like of the constituent members are not limited to the above-described embodiments, and the number, position, shape, and the like that are suitable for implementing the present invention can be used.

1 is an overall configuration diagram illustrating an image forming apparatus according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view showing a process cartridge installed in the image forming apparatus of FIG. 1. FIG. 3 is a perspective view showing a state in which the process cartridge of FIG. 2 is mounted on the apparatus main body. It is sectional drawing which looked at the state of FIG. 3 from A viewing direction. FIG. 4 is a perspective view showing a state in which the mounting of the process cartridge in FIG. 3 is completed. It is sectional drawing which looked at the state of FIG. 5 from A viewing direction. FIG. 3 is a perspective view showing a state in which the process cartridge of FIG. 2 is detached from the apparatus main body. It is sectional drawing which looked at the state of FIG. 7 from the A viewing direction. It is sectional drawing which shows the image forming apparatus in Embodiment 2 of this invention.

Explanation of symbols

1 image forming apparatus body (apparatus body),
2 accommodating part, 2a opening part, 3 exposure part,
4 Process cartridge, 7 Transfer section, 9 Fixing section,
11 lock lever (positioning member), 11a tip, 15 door,
18 Photosensitive drum (image carrier), 19 Charging unit,
20 developing section, 21 cleaning section, 22 holes (engaging section),
24 release lever (release member), 24a contact part (one end),
24b bent part (other end), 25 shaft part (swing center),
26 gripping portion, 28 torsion coil spring (biasing member).

Claims (9)

A process cartridge that is detachably installed in the image forming apparatus main body,
A gripping part for performing an attaching / detaching operation with respect to the image forming apparatus main body;
An engaging portion configured to be engageable with a positioning member provided in the image forming apparatus main body;
A release member configured to be able to release the engagement between the engagement portion and the positioning member,
The releasing member is configured to release the engagement between the engaging portion and the positioning member in conjunction with an operation of being held together with the holding portion when performing a detachment operation from the image forming apparatus main body. A process cartridge characterized by that. The process cartridge according to claim 1, wherein the release member is configured to be gripped together with the grip portion when performing an attachment / detachment operation on the image forming apparatus main body. The process cartridge according to claim 1, wherein the engaging portion is configured to engage with the positioning member in conjunction with a mounting operation to the image forming apparatus main body. The release member is a release lever supported to be swingable,
The positioning member is a lock lever that is swingably supported by the image forming apparatus main body,
4. The process cartridge according to claim 1, wherein the engagement portion is a hole in which a distal end portion of the lock lever is engaged and one end of the release lever is provided close to the engagement portion. . The release lever swings, the one end of the release lever abuts on the tip of the lock lever, and the lock lever swings to release the engagement between the hole and the lock lever. The process cartridge according to claim 4. 6. The process cartridge according to claim 4, wherein the other end of the release lever via the swing center is gripped together with the grip portion. The process cartridge according to claim 1, further comprising an urging member that urges the release member in a direction close to the grip portion. The process cartridge according to claim 7, wherein the biasing member is a torsion coil spring. An image forming apparatus comprising the process cartridge according to claim 1, the image forming apparatus main body, and the positioning member.

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