JP2009047770A - Process cartridge and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a process cartridge capable of achieving miniaturization and reduction of cost by making the operating range of a shutter or a shutter opening/shutting member as narrow as possible while surely opening the shutter with simple constitution. <P>SOLUTION: The process cartridge 7 having a photoreceptor drum 1 and constituted to be freely attached to/detached from the image forming apparatus while it is guided by attaching guides 45 and 46 provided in the image forming apparatus includes the shutter 40 and the shutter opening/shutting member 42 opening/shutting the shutter 40. By biasing a part 42a3 to be biased of a shutter opening/shutting member provided in the shutter opening/shutting member 42, the shutter 40 is opened. By biasing the part 42a3 to be biased of the shutter opening/shutting member from the attaching guides 45 and 46 when the process cartridge 7 is attached to the image forming apparatus along the attaching guides 45 and 46, the shutter 40 is opened. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a process cartridge including an image carrier and an image forming apparatus including the process cartridge.

  2. Description of the Related Art Conventionally, in an image forming apparatus that employs an electrophotographic system, a process drum in which a photosensitive drum, a developing unit, and the like as an image carrier are integrally formed into a cartridge and the cartridge can be attached to and detached from the image forming apparatus main body The method is adopted.

  According to the process cartridge system, the maintenance of the apparatus main body can be performed by the user without relying on the service person, so that the operability of the apparatus main body can be remarkably improved.

  As such a process cartridge, there is known a cartridge provided with an openable / closable shutter provided to shield and protect the photosensitive drum from the outside, and a shutter opening / closing member for opening / closing the shutter.

  When an image is formed by attaching a process cartridge to the apparatus main body, the photosensitive drum is exposed from the process cartridge in order to irradiate the surface of the photosensitive drum with laser light emitted from an exposure unit provided adjacent to the process cartridge. There is a need. That is, it is necessary to open the shutter to a predetermined position.

  On the other hand, when removing the process cartridge from the main body of the image forming apparatus during maintenance work, etc., the photosensitive drum is shielded from the outside and protected to prevent the surface of the photosensitive drum from being contaminated or damaged. It is desirable to do. That is, it is desirable to close the shutter.

Therefore, there is a need for a process cartridge having an openable / closable shutter that can expose the photosensitive drum during image formation and otherwise shield the photosensitive drum from the outside. Therefore, Patent Documents 1 and 2 disclose the configuration of a process cartridge including such a shutter and an image forming apparatus.
Japanese Patent Laid-Open No. 10-104946 Japanese Patent Laid-Open No. 10-104947

  However, the process cartridge and the image forming apparatus according to the conventional example have the following problems.

  The process cartridge and the image forming apparatus according to the conventional example are provided with a shutter opening / closing member for opening / closing the shutter in the process cartridge, and the shutter opening / closing guide member for opening / closing the shutter by acting on the shutter opening / closing member in one image forming apparatus. Is provided. Further, the image forming apparatus is provided with a mounting guide for guiding the mounting of the process cartridge to the apparatus main body.

When the process cartridge is mounted on the image forming apparatus with this configuration, the process cartridge is first guided by the mounting guide and positioned at a predetermined position in the apparatus main body. During this time, the shutter opening / closing guide member of the image forming apparatus acts on the shutter opening / closing member of the process cartridge to open the shutter to a predetermined position. In other words, the shutter that was closed before mounting is in an open state after mounting on the image forming apparatus main body.

  However, in the process cartridge and the image forming apparatus according to the conventional example, the shutter opening / closing guide member of the image forming apparatus is provided as a separate component from the mounting guide for guiding the mounting operation of the process cartridge.

  When the shutter opening / closing guide member is provided independently in the image forming apparatus as described above, it is necessary to provide the shutter opening / closing guide member accurately in the image forming apparatus in order to cause the shutter opening / closing guide member to act accurately on the shutter opening / closing member. .

  If variations occur in the position where the shutter opening / closing guide member is attached, it is difficult to cause the shutter opening / closing guide member to act stably on the shutter opening / closing member, so it is difficult to open the shutter to a predetermined position.

  For this reason, in the process cartridge and the image forming apparatus according to the above-described conventional examples, the operating range of the shutter and the shutter opening / closing member is widened so that the shutter opening / closing guide member can be reliably opened / closed even when the mounting accuracy of the shutter opening / closing guide member is somewhat low. It was necessary to secure.

  As a result, the process cartridge and the image forming apparatus have been increased in size. Furthermore, since it is necessary to provide the shutter opening / closing guide member with high accuracy to the image forming apparatus, the manufacturing cost has increased due to an increase in the number of components and a complicated manufacturing process.

  An object of the present invention is to provide a process cartridge and an image forming apparatus capable of achieving downsizing and cost reduction.

  In order to achieve the above object, according to the present invention, in a process cartridge which is guided by a mounting guide provided in an image forming apparatus and is detachable from a mounting portion, the process cartridge includes an image carrier, A shutter that can take a shielding position that shields the image carrier and an exposure position that exposes the image carrier, and a biased portion that is biased to move the shutter from the shielding position to the exposure position; A guided portion that abuts the mounting guide, and when the mounting portion is mounted, the guided portion is guided by the mounting guide, and the biased portion is attached to the mounting guide. And the shutter is moved from the shielding position to the exposure position.

  Further, the image forming apparatus of the present invention includes an image carrier, a shutter that can take a shielding position that shields the image carrier and an exposure position that exposes the image carrier, and the shutter from the shielding position to the exposure position. A process cartridge having a biased portion that is biased to move to the mounting portion, a mounting portion to which the process cartridge is mounted, and the shutter when the process cartridge is mounted to the mounting portion. And a mounting guide for urging the urged portion to move the urged portion to the exposed position and guiding the guided portion provided in the process cartridge.

  According to the present invention, it is possible to provide a process cartridge and an image forming apparatus that achieve miniaturization and cost reduction.

  The best mode for carrying out the present invention will be exemplarily described in detail below based on the embodiments with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. Absent.

[Entire configuration of image forming apparatus]
With reference to FIG. 1, the overall configuration of the image forming apparatus according to the present embodiment will be described. FIG. 1 shows a schematic configuration in a cross section of an image forming apparatus according to the present embodiment.

  An image forming apparatus 100 that forms an image on a recording medium includes four detachable process cartridge mounting portions 99 (see FIG. 8) that are arranged in parallel with an inclination with respect to the horizontal direction. Each of the process cartridges 7 (7a to 7d) includes a photosensitive drum 1 (1a to 1d) as one image carrier. The process cartridge 7 will be described later.

  A scanner unit 3 (exposure unit) that emits laser light L to the surface of each photosensitive drum 1 based on image information is provided at a position adjacent to the process cartridge 7.

  The scanner unit 3 is provided substantially in parallel with the direction in which the process cartridges 7 are arranged, and has four light sources (not shown) therein. As described above, by providing the process cartridge 7 and the scanner unit 3 so as to be inclined with respect to the horizontal direction, it is possible to reduce the size of the image forming apparatus.

  When the laser light L is emitted from the scanner unit 3 and an electrostatic latent image is formed on the photosensitive drum 1 whose surface is uniformly charged in advance, toner is supplied to the electrostatic latent image in the process cartridge 7. The electrostatic latent image is developed as a toner image.

  The toner images are sequentially transferred (primary transfer) onto the intermediate transfer belt 5 at the nip portion between the primary transfer rollers 51 (51a to 51d) provided in contact with the respective photosensitive drums 1 and the photosensitive drums 1. The

  In the present embodiment, the toner image on the surface of the photosensitive drum 1 is negatively charged. Therefore, a toner image can be primarily transferred from the surface of the photosensitive drum 1 onto the intermediate transfer belt 5 by applying a positive bias to the primary transfer roller.

  The intermediate transfer belt 5 is moved in the direction of arrow A in FIG. 1 by the driving roller 56, and the primary transferred toner image is conveyed to the nip portion of the secondary transfer roller 52. Then, at the nip portion of the secondary transfer roller 52, the toner is applied to the sheet material (recording medium) S conveyed from the feeding tray 17 disposed at the lower part of the apparatus main body through the feeding roller 54, the conveying roller 76, and the registration roller 55. The image is transferred (secondary transfer). At this time, secondary transfer is performed by applying a positive bias to the secondary transfer roller 52.

  The sheet material S to which the toner image is transferred is conveyed to the fixing device 106, and the toner image on the sheet material S is fixed. Then, the sheet material S is discharged from the discharge roller pair 107 to the outside of the apparatus main body.

[Process cartridge configuration]
The configuration of the process cartridge 7 according to this embodiment will be described with reference to FIGS. FIG. 2 shows a schematic configuration in a cross section of the process cartridge 7 according to the present embodiment. In this embodiment, the process cartridges 7a to 7d are provided for each color of yellow, magenta, cyan, and black. However, these process cartridges have substantially the same configuration.

  The process cartridge 7 is a cartridge in which the charging unit 26 and the developing unit 4 are made into a cartridge. In FIG. 2, the right side is the charging unit 26, the left side is the developing unit 4, and both are connected by a pressure spring 38.

  Further, the process cartridge 7 is provided with a shutter 40 for protecting the photosensitive drum 1. The configuration of the shutter 40 will be described later.

  The charging unit 26 includes a photosensitive drum 1 that is driven to rotate, a charging roller 2 that contacts the surface of the photosensitive drum 1, a cleaning member 6, and a cleaning frame 27 as a frame.

  The photosensitive drum 1 is rotatably attached to the cleaning frame 27 via a bearing (not shown). Further, the charging roller shaft 2j is attached to the charging roller bearing 39, and the pressing member 46 urges the charging roller bearing 39 so that the charging roller 2 can move in the direction of arrow D in FIG.

  The cleaning member 6 is provided to remove the toner remaining on the surface of the photosensitive drum 1. As shown in FIG. 2, the cleaning member 6 rubs against the surface of the photosensitive drum 1, whereby the residual toner on the photosensitive drum 1 can be scraped off into the removed toner chamber 27a.

  The developing unit 4 includes a developing roller 25 that contacts the photosensitive drum 1 and rotates in the direction of arrow B in FIG. 2, a supply roller 34 that contacts the developing roller 25, and a toner conveying member 36. It is housed together.

  The developing roller 25 attaches toner to the electrostatic latent image formed on the surface of the photosensitive drum 1, and the developing blade 35 and the developing roller 25 rub against each other to charge the toner on the developing roller 25. It is a configuration.

  A supply roller 34 provided in contact with the developing roller 25 supplies the toner conveyed by the toner conveying member 36 from the toner accommodating portion 31a onto the developing roller 25, and is provided in the direction of arrow C in FIG. Rotate.

  A bearing member 32R (32L) is provided on the side surface of the developing frame 31 on the charging unit 26 side, and the shaft 37R (37L) is supported in the hole 32Rb (32Lb) formed in the bearing member 32. The developing unit 4 and the charging unit 26 are rotatably connected.

  With the above configuration, during image formation, the developing unit 4 is rotated about the shaft 37R (37L) by being biased by the pressure spring 38, and the developing unit 4 reaches a position where the developing roller 25 contacts the photosensitive drum 1 with a predetermined pressure. Rotates.

  On the other hand, when image formation is not performed, the developing unit 4 is rotated by a pressing unit (not shown), and the developing roller 25 is separated from the photosensitive drum 1.

[Configuration and operation of shutter]
With reference to FIGS. 3 to 7, the configuration and operation of the shutter in the present embodiment will be described. FIG. 3 shows a state when the process cartridge according to the present embodiment is mounted on the image forming apparatus 100, and FIGS. 4 to 7 show a schematic configuration of the process cartridge 7 according to the present embodiment. Is.

  In the state where the process cartridge 7 is mounted on the image forming apparatus, the shutter 40 in the present embodiment opens so that the surface of the photosensitive drum 1 in the process cartridge 7 is exposed to the scanner unit 3 (this position is set). Called exposure position). When the process cartridge 7 is detached from the image forming apparatus, the photosensitive drum 1 is closed so as to be shielded from the outside (this position is referred to as a shielding position). That is, the shutter 40 can take an exposure position and a shielding position.

  The shutter 40 is opened and closed by biasing a shutter opening / closing member biased portion 42a3 (biased portion) provided in the process cartridge 7 by a mounting guide that guides the mounting of the process cartridge 7. In the present embodiment, the shutter opening / closing member biased portion 42a3 provided as the biased portion is provided in the shutter opening / closing member 42 having a link mechanism.

  As described above, the present embodiment is characterized in that the mounting guide for guiding the mounting of the process cartridge 7 also plays a role of opening and closing the shutter 40.

  When attaching the process cartridge 7 to the image forming apparatus 100, the front cover 101 of the image forming apparatus 100 is opened in the M direction in FIG. 3, and each process is performed from the opening 82a formed in the front side plate 82 of the apparatus main body. The cartridge 7 is inserted in the direction of arrow I. At this time, the shutter 40 is closed, and the photosensitive drum 1 is not exposed to the outside.

  In the present embodiment, the side on which the opening 82a is provided is the front side of the apparatus main body (upstream side in the mounting direction), and the direction where the process cartridge 7 is inserted is the back side of the apparatus main body (downstream side in the mounting direction). Will be described.

  As shown in FIG. 3, a photosensitive drum front bearing 30 is provided on the front side of the photosensitive drum 1, and a positioning hole 30 a is formed in the photosensitive drum front bearing 30. On the other hand, an abutting portion 85 and a positioning member 84 are provided on the image forming apparatus 100 side.

  When the process cartridge 7 is inserted, the positioning hole 30 a comes into contact with the positioning member 84 and the photosensitive drum front bearing 30 comes into contact with the abutting portion 85, thereby positioning the process cartridge 7 with respect to the image forming apparatus.

  Next, the opening / closing operation of the shutter 40 will be described with reference to FIGS. 4 and 5 are perspective views of the process cartridge according to the present embodiment (FIG. 4: view from the downstream side in the mounting direction, FIG. 5: view from the upstream side in the mounting direction). 6 and 7 are schematic configuration diagrams when the process cartridge according to the present embodiment is viewed from the side surface on the downstream side in the mounting direction.

  The process cartridge 7 includes a shutter 40, a shutter shaft 41 that can be connected to the shutter 40 and moved, and a shutter opening / closing member 42.

  As shown in FIG. 6, on the downstream side in the mounting direction of the process cartridge 7, one end of the shutter shaft 41 is in the shutter shaft engaging portion 40 b of the shutter 40 and the other end is in the shutter shaft support hole 41 a provided in the cleaning frame body 27. It is mated.

  As shown in FIG. 5, one end of the shutter shaft 41 is also rotatably fitted in a shutter shaft support hole 41 b provided in the cleaning frame 27 on the upstream side in the mounting direction of the process cartridge 7.

According to this configuration, the shutter shaft 41 can be connected to the shutter 40 at the shutter shaft engaging portion 40b (see FIG. 6), and the shutter 40 can be movably locked to the process cartridge 7.

  A shutter opening / closing member 42 that opens and closes the shutter 40 is provided downstream of the process cartridge 7 in the mounting direction. The shutter 40 is opened when an external urging means urges the shutter opening / closing member urging portion 42a3 (showing urging portion) provided in the shutter opening / closing member 42. The opening / closing operation of the shutter 40 will be described later.

  As shown in FIGS. 6 and 7, the shutter opening / closing member 42 has a link mechanism including a first link 42a (arm) and a second link 42b (arm), and the link mechanism includes a shutter opening / closing member cover. An urging unit 42a3 (an urging unit) is connected.

  A first link hole 42a1 is formed at one end of the first link 42a, and a first link rotation shaft 42a2 is formed at the other end.

  The first link hole 42a1 is fitted into the support shaft 27d formed in the cleaning frame 27, and the first link turning shaft 42a2 is fitted into the second link turning hole 42b2 formed in the second link 42b. . Further, the shutter opening / closing member biased portion 42a3 is rotatably fitted to the support shaft 27d.

  Further, the second link turning hole 42b2 described above is formed at one end of the second link 42b, and the second link hole 42b1 is fitted into the support shaft 27e formed in the cleaning frame 27. The shutter support shaft 42b3 is formed at the other end.

  The shutter support shaft 42b3 is engaged with the shutter 40 at the engaging portion 40c. The second link 42 b receives a biasing force from a spring (not shown) and is biased toward the photosensitive drum 1 in a direction in which the shutter 40 is closed.

  That is, in the process cartridge 7 according to the present embodiment, the shutter opening / closing member biased portion 42a3, the first link 42a, and the second link 42b are connected as a series of link mechanisms.

  Further, since the shutter support shaft 42b3 provided at the end of the second link 42b is engaged with the shutter 40 at the engaging portion 40c, the shutter opening / closing member biased portion 42a3 is biased to open / close the shutter 40. Can be operated.

  For example, FIG. 6 shows a schematic configuration of the process cartridge 7 in a state in which the shutter 40 is closed. When the shutter opening / closing member biased portion 42a3 is biased in the direction of arrow F in this state, first, the first link 42a. Rotates in the direction of arrow G about the support shaft 27d.

  When the first link 42a rotates in the arrow G direction, the rotational motion is transmitted from the first link rotating shaft 42a2 to the second link rotating hole 42b2, and the second link 42b rotates in the arrow H direction around the support shaft 27e. To do.

  When the second link 42b rotates in the arrow H direction, the shutter 40 that engages with the second link 42b is opened in the engaging portion 40c, and the state shown in FIG. 7 is obtained.

  Conversely, when closing the shutter 40, the second link 42b is urged in the direction of the arrow H 'in FIG. 7 by a spring (not shown), so that the shutter 40 is closed and the second link 42b is moved in the direction opposite to that when the shutter 40 is opened. The one link 42a and the shutter opening / closing member biased portion 42a3 rotate.

  Specifically, the second link 42b rotates about the support shaft 27e in the direction of the arrow H ', and rotates from the second link rotation shaft hole 42b2 to the first link rotation shaft 42a2 in the direction of the arrow G'. Is transmitted.

  Then, the shutter opening / closing member biased portion 42a3 rotates about the support shaft 27d in the direction of the arrow F 'and moves to the position shown in FIG.

[Mounting mechanism of process cartridge to image forming apparatus main body]
With reference to FIGS. 8 and 9, a mounting process when the process cartridge according to the present embodiment is mounted on the image forming apparatus will be described. FIG. 8 shows a state when the process cartridge is mounted on the image forming apparatus as viewed from the right side when viewed from the front side of the image forming apparatus. FIG. 9 shows a state where the process cartridge is mounted on the image forming apparatus as viewed from the downstream side in the mounting direction.

  In the present embodiment, a mounting guide member (upper guide member 45, lower guide member 46) is provided in the image forming apparatus main body, and the process cartridge 7 is mounted on the image forming apparatus along the mounting guide member.

  Further, a shutter opening / closing member biased portion 42a3 provided in the shutter opening / closing member 42 is configured to abut against the upper guide member 45, and the upper guide member 45 can bias the shutter opening / closing member biased portion 42a3 when mounted. did.

  The configuration of the mounting guide members (upper guide member 45, lower guide member 46) in the present embodiment will be described.

  A first flat portion 45a, a first taper portion 45b, a second taper portion 45c, and a second flat portion 45d are formed on the upper guide member 45 sequentially from the upstream side in the process cartridge mounting direction (FIG. 8A). To (c)).

  In addition, a first flat portion 46a, a first taper portion 46b, and a second flat portion 46c are formed on the lower guide member 46 sequentially from the upstream side in the process cartridge mounting direction (FIGS. 8A to 8C). )).

  Then, the upper guided member 43 of the process cartridge 7 contacts the upper guide member 45 (that is, the upper guide member 45 guides the upper guided member 43). Further, the shutter opening / closing member biased portion 42a3 also contacts the upper guide member 45. Further, the lower guided portion 44 of the process cartridge 7 abuts against the lower guide member 46 (that is, the lower guide member 46 guides the lower guided portion 44). In this way, the process cartridge 7 is mounted on the mounting portion 99.

  When the process cartridge 7 is attached to the image forming apparatus, first, the first flat portion 45a of the upper guide member 45 and the first flat portion 46a of the lower guide member abut against the process cartridge 7, and the process cartridge 7 is attached. Guide in the I direction in FIG.

  While the process cartridge 7 is guided by the first flat portion 45a of the upper guide member 45 and the first flat portion 46a of the lower guide member 46, the shutter 40 is kept closed.

That is, as shown in FIG. 9A, the shutter opening / closing member biased portion 42a3 is substantially in contact with the first flat portion 45a of the upper guide member 45, but the shutter opening / closing member biased portion 42a3. Has not yet been urged downward, the shutter 40 does not open.

  When the process cartridge 7 is further inserted downstream in the mounting direction, the first taper portion 45b of the upper guide member 45 comes into contact with the shutter opening / closing member biased portion 42a3 (FIG. 8B).

  As shown in FIG. 8, the first tapered portion 45 b of the upper guide member 45 has a tapered surface in a direction in which the distance between the upper guide member 45 and the lower guide member 46 is narrowed. That is, in this section, the interval between the upper guide member 45 and the lower guide member 46 is narrowed.

  Therefore, the shutter opening / closing member biased portion 42a3 is pushed into the first tapered portion 45b of the upper guide member 45 and biased, and rotates downward. FIG. 9B shows a state where the shutter opening / closing member biased portion 42a3 is biased by the first tapered portion 45b of the upper guide member 45 and rotates in the F direction.

  Thus, as the process cartridge 7 advances along the first taper portion 45b of the upper guide member 45 along the mounting direction, the shutter opening / closing member biased portion 42a3 rotates downward and the shutter 40 begins to open to a predetermined position.

  When the process cartridge 7 is further inserted downstream in the mounting direction, the shutter opening / closing member biased portion 42 a 3 is at the second tapered portion 45 c of the upper guide member 45, and the lower guided portion 44 is at the first taper of the lower guide member 46. It contacts the part 46b. This state is shown in FIG.

  In this state, the shutter 40 is open to a desired position, and the distance between the second taper portion 45c of the upper guide member 45 and the first taper portion 46b of the lower guide member 46 does not change. The member biased portion 42a3 maintains a state of being biased downward. That is, the shutter 40 continues to be opened to a desired position (FIG. 9C).

  When the process cartridge 7 is further inserted downstream in the mounting direction, the shutter opening / closing member biased portion 42 a 3 is placed on the second flat portion 45 d of the upper guide member 45, and the lower guided portion 44 is placed on the second flat portion of the lower guide member 46. It contacts the part 46c. This state is shown in FIG.

  In this state, the shutter 40 is kept open. At that time, the positioning portion 29a of the photosensitive drum back side bearing 29 attached to the cleaning frame 27 enters the positioning hole 83a of the rear plate 83, and the abutting portion 29b contacts the rear plate 83, so that the process cartridge 7 Positioning in the mounting direction is performed.

  Further, the rotation stop shaft 27b attached to the cleaning frame 27 is fitted in the rotation stop groove 46g of the lower guide member 46, and the rotation of the process cartridge 7 with respect to the image forming apparatus is stopped.

  Thereafter, on the back side of the process cartridge 7, the positioning portion 29 a of the photosensitive drum back side bearing 29 is pressed in the direction of the arrow N by a pressing member (not shown) and is brought into contact with the positioning butting portion 83 b of the rear plate 83. The cartridge 7 is positioned on the image forming apparatus main body.

  Further, on the front side of the process cartridge 7, when positioning in the mounting direction of the process cartridge 7 is performed, the positioning hole 30 a of the photosensitive drum front side bearing 30 is fitted with the positioning member 84 mounted on the front side plate and is not illustrated. It is pressed in the direction of arrow N by the pressing member.

Then, the photosensitive drum front bearing 30 is brought into contact with the positioning butting portion 85 of the front plate, and the process cartridge 7 is positioned on the image forming apparatus main body.

  With the above operation, the mounting of the process cartridge 7 is completed, and the process cartridge 7 is positioned in the image forming apparatus. That is, this state is a state where the process cartridge 7 is mounted on the mounting portion 99.

  In this state, the shutter 40 is open, but the photosensitive drum 1 is not in contact with the intermediate transfer belt 5. The contact between the two is performed by controlling the intermediate transfer belt 5 by a control means (not shown) provided in the image forming apparatus after the process cartridge 7 is positioned on the image forming apparatus.

  As described above, in the present embodiment, in the process of mounting the process cartridge 7, the mounting guide 7 biases the shutter opening / closing member biased portion 42 a 3 to open the shutter 40.

  In the present embodiment, the upper guide member 45 is configured to bias the shutter opening / closing biased portion 42a3, but the lower guide member 46 is biased to the shutter opening / closing biased portion 42a3 to open the shutter. It may be a configuration.

  According to the configuration of the present embodiment, there is no need to separately provide a member (shutter opening / closing guide member) for urging the shutter opening / closing member urged portion 42a3, so the shutter opening / closing member urged portion 42a3 is urged with high accuracy. Thus, the shutter can be reliably opened and closed.

  Further, the shutter opening / closing member 42 is a link mechanism formed of a plurality of arms, so that the shutter 40 can be opened / closed by a sufficient amount while keeping the rotation range of the shutter opening / closing member biased portion 42a3 at a small stroke. Become.

  Further, in the process cartridge 7 according to the present embodiment, the axial direction (longitudinal direction) of the photosensitive drum 1 and the mounting direction of the process cartridge 7 are the same, and the shutter 40 is in a direction orthogonal to the mounting direction of the process cartridge 7. It can be opened and closed.

  According to this configuration, the surface of the photosensitive drum 1 can be exposed over the entire length direction only by opening the shutter 40 by a predetermined amount in the circumferential direction of the photosensitive drum 1. That is, the opening / closing range of the shutter 40 can be suppressed to a small range.

  As a result, since it is not necessary to ensure a large operating range of the shutter opening / closing member as in the prior art, the size of the shutter opening / closing member can be reduced, and the space around the process cartridge can be reduced.

  Also in the image forming apparatus according to the present embodiment, by providing a shutter opening / closing function in the mounting guide without separately providing a shutter opening / closing guide member, the cost can be reduced by reducing the number of parts.

  That is, while the process cartridge 7 is guided in the mounting direction by the upper guide member 45 and the lower guide member 46, a section in which the distance between the two guide members is narrowed is provided, so that the upper guide member 45 is provided with the shutter opening / closing member biased portion 42a3. Is configured to be energized. Therefore, it is not necessary to separately provide a member for urging the shutter opening / closing member urged portion 42a3.

In the present embodiment, the shutter 40 is configured to open in the direction indicated by the arrow H in FIG. 6, but the opening direction of the shutter 40 is not limited to this. That is, the structure opened in the direction opposite to the arrow H direction in FIG.

  As described above, in the process cartridge or the image forming apparatus according to the present embodiment, the shutter can be reliably opened with a simple configuration. Furthermore, it is possible to provide a process cartridge and an image forming apparatus capable of achieving downsizing and cost reduction by narrowing the operating range of the shutter or the shutter opening / closing member as much as possible.

Schematic configuration diagram of an image forming apparatus according to the present embodiment Schematic configuration diagram of a process cartridge according to the present embodiment The figure which shows the mounting method of the process cartridge which concerns on this Embodiment The perspective view of the process cartridge which concerns on this Embodiment The perspective view of the process cartridge which concerns on this Embodiment Schematic configuration diagram when the process cartridge according to the present embodiment is viewed from the side Schematic configuration diagram when the process cartridge according to the present embodiment is viewed from the side The figure which shows the mounting process of the process cartridge which concerns on this Embodiment The figure which shows the opening / closing operation | movement of the shutter in this Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photosensitive drum 7 Process cartridge 27 Cleaning frame 29 Photosensitive drum back side bearing 29a Positioning part 29b Abutting part 40 Shutter 41 Shutter shaft 42 Shutter opening / closing member 42a3 Shutter opening / closing member urging part 43 Upper guided part 45 Upper guide member 45a 1st flat part 45b 1st taper part 45c 2nd taper part 45d 2nd flat part 46 Lower guide member 46a 1st flat part 46b 1st taper part 46c 2nd flat part

Claims (9)

In a process cartridge that is detachable from the mounting portion while being guided by a mounting guide provided in the image forming apparatus,
The process cartridge is
An image carrier;
A shutter capable of taking a shielding position for shielding the image carrier and an exposure position for exposing the image carrier;
A biased portion that is biased to move the shutter from the shielding position to the exposure position;
A guided portion that comes into contact with the mounting guide;
Have
When mounted on the mounting portion, the guided portion is guided by the mounting guide, the biased portion is biased by the mounting guide, and the shutter moves from the shielding position to the exposed position. A process cartridge. The axial direction of the image carrier and the mounting direction of the process cartridge are the same,
The shutter is
The process cartridge according to claim 1, wherein the process cartridge can be opened and closed in a direction orthogonal to a mounting direction of the process cartridge. The biased part is
The process cartridge according to claim 1, wherein the process cartridge is provided on the downstream side in the mounting direction of the process cartridge. The process cartridge is
A shutter opening / closing member having a link mechanism formed of a plurality of arms connected to be movable;
The biased portion is provided on the shutter opening / closing member,
4. The process cartridge according to claim 1, wherein the shutter is opened and closed by connecting the biased portion and the shutter via the link mechanism. 5. In an image forming apparatus for forming an image on a recording medium,
An image carrier, a shutter that can take a shielding position that shields the image carrier and an exposure position that exposes the image carrier, and a subject that is biased to move the shutter from the shielding position to the exposure position. A process cartridge having an urging unit;
A mounting portion to which the process cartridge is mounted;
When the process cartridge is mounted on the mounting portion, the biased portion is biased to move the shutter from the shielding position to the exposed position, and the guided portion provided in the process cartridge A mounting guide that guides
An image forming apparatus comprising: The mounting guide is
An upper guide portion for guiding the upper side of the process cartridge;
A lower guide portion for guiding the lower side of the process cartridge;
With
In the image forming apparatus,
A section in which the interval between the upper guide and the lower guide is reduced along the mounting direction of the process cartridge is provided,
The structure is characterized in that, in the section, the shutter is opened by urging the urged portion to either the upper guide or the lower guide while guiding the mounting direction. The image forming apparatus according to 5. The axial direction of the image carrier and the mounting direction of the process cartridge are the same,
The shutter is
The image forming apparatus according to claim 5, wherein the image forming apparatus can be opened and closed in a direction orthogonal to a mounting direction of the process cartridge. The biased part is
The image forming apparatus according to claim 5, wherein the image forming apparatus is provided on a downstream side in the mounting direction of the process cartridge. The process cartridge is
A shutter opening / closing member having a link mechanism formed of a plurality of arms connected to be movable;
The biased portion is provided on the shutter opening / closing member,
The image forming apparatus according to claim 5, wherein the shutter is opened and closed by connecting the biased portion and the shutter via the link mechanism.

Images