Process cartridge

Abstract

To protect a cartridge, while scaling the cartridge down.SOLUTION: A process cartridge has: a drum unit that has a photoconductor drum with a first direction as a rotation axis direction, and a driving unit; a frame body that exposes a part of the drum unit from an opening part staying opened in a second direction; a shutter member that shields a surface of the photoconductor drum of the exposed part of the drum unit; and a link member that links the frame body to the shutter member, and is rotatable in a third direction. The shutter member is movable in the third direction from a shield position of the photoconductor drum to an open position due to rotation of the link member, a linkage part of the link member and shutter member in the shield position is positioned in a part on a third direction positive direction side in the shutter member, the link member has a first part that extends in a direction forward a non-driving side from a driving side in a first direction outside of the shutter member from the linkage part, the first part in the shield position has at least a part overlapped with the driving unit in the first direction, and has at least a part overlapped with the driving unit when viewing in the second direction.SELECTED DRAWING: Figure 1(a)

Description

Technical Field

[0001] The present invention relates to a process cartridge.

Background Art

[0002] In a process cartridge detachable from the main body of an image forming apparatus, if scratches or dents are formed on a photosensitive drum or a drive unit such as a gear unit that inputs a driving force to the photosensitive drum, image defects may occur. Therefore, even when the process cartridge is removed from the image forming apparatus, a configuration has been proposed to protect the photosensitive drum and the drive unit from being scratched or dented. For example, in Patent Document 1, a configuration is disclosed in which a photoreceptor and electrical contacts are protected by a link member and a shutter member for protecting the photosensitive drum.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, since both the photosensitive drum and the drive unit for driving the photosensitive drum are protected by a shutter member, a large-sized shutter member is required to cover both the photosensitive drum and the drive unit, which may cause the process cartridge to be enlarged.

[0005] An object of the present invention is to protect a cartridge while suppressing enlargement.

Means for Solving the Problems

[0006] The present invention is a process cartridge detachable from the main body of an image forming apparatus, A drum unit having a photosensitive drum rotatable about a rotation axis in a first direction, and a drive unit provided at an end of the photosensitive drum in the first direction. A frame that rotatably supports the drum unit, the frame having an opening that opens in a second direction intersecting the first direction, and being configured such that a part of the circumferential direction of the drum unit is exposed from the opening. A shutter member located downstream in the second direction with respect to the photosensitive drum exposed from the opening, the shutter member shielding the surface of the photosensitive drum among the part exposed from the opening of the drum unit. Taking a direction that rotates around an axis parallel to the first direction and intersects the second direction as a third direction, a link member that is rotatably supported by the frame in the third direction, to which the shutter member is attached, and that connects the frame and the shutter member. Having The shutter member is movable in the third direction between a shielding position where the shutter member rotates by the rotation of the link member and shields the exposed portion of the photosensitive drum, and an open position where the shutter member does not shield the exposed portion of the photosensitive drum. In the first direction, the side where the drive unit of the photosensitive drum is provided is defined as the drive side, and the side where the drive unit is not provided is defined as the non-drive side. In the third direction, the direction from the shielding position to the open position within the range where the shutter member is movable is defined as the positive direction. The link member is rotatably supported by a portion of the frame on the drive side in the first direction, and is attached to a portion of the shutter member on the drive side in the first direction. The connecting portion between the link member and the shutter member is located in a portion on the positive direction side in the third direction in a state where the shutter member is in the shielding position. The link member has a first portion that extends from the connecting portion to the outside of the shutter member in a direction from the non-drive side to the drive side in the first direction. In a state where the shutter member is in the shielding position, at least a part of the first portion overlaps with the driving portion in the first direction, and at least a part of the first portion overlaps with the driving portion when viewed in the second direction. A process cartridge characterized by this.

Advantages of the Invention

[0007] According to the present invention, it is possible to protect the cartridge while suppressing an increase in size.

Brief Description of the Drawings

[0008]

Fig. 1(a)

Fig. 1(b)

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Fig. 7

Fig. 8

Fig. 9

Fig. 10

Fig. 11

Fig. 12

Fig. 13(a)

Fig. 13(b)

Fig. 14

Fig. 15

Fig. 16(a)

Fig. 16(b)

Fig. 17(a)

Fig. 17(b)

Fig. 18

Best Mode for Carrying Out the Invention

[0009] Hereinafter, exemplary embodiments for carrying out the present invention will be described with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described in the following examples should be appropriately changed according to the configuration of the apparatus to which the present invention is applied and various conditions, and are not intended to limit the scope of the present invention to the following examples.

[0010] The following examples relate to an image forming apparatus that forms an image on a recording medium using an electrophotographic method. This is the case. Examples of electrophotographic image forming apparatuses include electrophotographic copiers, electrophotographic printers (such as LED printers, laser beam printers, etc.), facsimile apparatuses, and word processors. In an electrophotographic image forming apparatus, an electrophotographic photoreceptor as an image carrier is uniformly charged. Next, an electrostatic image is formed on the photoreceptor by selectively exposing the charged photoreceptor. Next, the electrostatic image formed on the photoreceptor is visualized as a toner image using toner as a developer. Then, the toner image formed on the photoreceptor is transferred to a recording material such as recording paper or a plastic sheet, and the toner image transferred onto the recording material is fixed to the recording material by applying heat or pressure to perform image recording.

[0011] Such an image forming apparatus generally requires maintenance of various process means. In order to facilitate the maintenance of these various process means, it has been put into practical use to integrate photoreceptors, charging means, developing means, cleaning means, etc. as described above into a cartridge within a frame and make it a process cartridge that is detachable from the apparatus main body of the image forming apparatus. According to the process cartridge method, an image forming apparatus with excellent usability can be provided.

[0012] <Example 1> Example 1 will be described with reference to FIGS. 1 to 18. First, the schematic configuration of the image forming apparatus of Example 1 will be described with reference to FIG. 2.

[0013] [Image Forming Apparatus] The image forming apparatus 200 of Example 1 is a laser printer using the electrophotographic method. As shown in FIG. 2, the image forming apparatus 200 includes an apparatus main body (printer main body) A, a process cartridge B as an image forming unit, and a toner cartridge C. In the apparatus main body A, a laser scanner 101, a sheet conveyance unit 102, a sheet feeding unit 103, a transfer roller 104, a fixing unit 105, a sheet discharge unit 110, a reverse conveyance unit 111, etc. are installed. Also, although it will be described in detail later, the process cartridge B and the toner cartridge C are detachably arranged in the apparatus main body A. For this purpose, the apparatus main body A has an opening / closing door 107.

[0014] Process cartridge B includes a photosensitive drum 11 as an image carrier and a photoreceptor, a charging roller 12 as a charging member, a developing unit 15, and a cleaning blade 17 as a cleaning member. Above the process cartridge B, a laser scanner 101 as an exposure device is disposed.

[0015] The charging roller 12 is disposed so as to contact the outer peripheral surface of the photosensitive drum 11, and charges the photosensitive drum 11 by applying a voltage from the apparatus main body A. Further, the charging roller 12 rotates passively as the photosensitive drum 11 rotates. The developing unit 15 includes a developing roller 16 as a developer carrier that carries and conveys toner as a developer. The developing roller 16 is disposed so as to face the photosensitive drum 11.

[0016] The cleaning blade 17 is an elastic member disposed so as to contact the outer peripheral surface of the photosensitive drum 11, and cleans the surface of the photosensitive drum 11. The cleaning blade 17 elastically contacts the photosensitive drum 11 at its tip, and removes toner remaining after a sheet S described later passes between the photosensitive drum 11 and the transfer roller 104 from the photosensitive drum 11.

[0017] The sheet feeding unit 103 includes a cassette 103a and a pickup roller 103b that feeds the uppermost sheet S housed in the cassette 103a. The sheet feeding unit 103 further includes a separation roller 103c and a separation pad 103d that separate the sheet S fed by the pickup roller 103b one by one. The sheet conveyance unit 102 includes a pair of conveyance rollers 102a that conveys the sheet S fed from the sheet feeding unit 103, and a pair of registration rollers 102b. The pair of registration rollers 102b conveys the sheet S to a transfer portion between the photosensitive drum 11 and the transfer roller 104 in synchronization with the toner image formed on the photosensitive drum 11.

[0018] The fixing unit 105 includes a fixing roller 105a heated by a heat source such as a heater, and a pressure roller 105b that forms a fixing nip for sandwiching the sheet between the fixing roller 105a. The sheet S onto which the toner image has been transferred in the transfer unit is conveyed to the fixing unit 105 and is heated and pressed at the fixing nip. Thereby, the toner image is fixed onto the sheet S.

[0019] The sheet discharge unit 110 has a pair of discharge rollers 110a, and discharges the sheet S onto which the toner image has been fixed to a discharge tray 106 by the pair of discharge rollers 110a. The reverse conveyance unit 111 has a pair of reverse conveyance rollers 111a. When forming images on both sides of the sheet S, the front and back of the sheet S that has passed through the fixing unit 105 are reversed and conveyed toward the pair of registration rollers 102b.

[0020] Subsequently, the operation of the image forming apparatus 200 will be described with reference to FIG. 2. The photosensitive drum 11 rotationally driven by a drive source (motor) (not shown) is uniformly charged to a predetermined potential by the charging roller 12. After charging, the photosensitive drum 11 is exposed based on image information by the laser scanner 101 on its surface, and the charges in the exposed portion are removed to form an electrostatic latent image. Toner is supplied from the developing roller 16 to the electrostatic latent image on the photosensitive drum 11 and visualized as a toner image.

[0021] On the other hand, in parallel with the formation operation of such a toner image, the sheet S is fed from the sheet feeding unit 103. The sheet S fed from the sheet feeding unit 103 is conveyed to the transfer unit by the registration roller pair 102b at the timing of forming a toner image on the photosensitive drum 11. When the sheet S passes through the transfer unit, a voltage is applied to the transfer roller 104 from the apparatus main body A, and the toner image on the photosensitive drum 11 is transferred to the sheet S as an unfixed image. Thereafter, the sheet S onto which the toner image has been transferred is conveyed to the fixing unit 105, and the unfixed image is heated and pressurized to be fixed on the surface of the sheet S. The sheet S on which the toner image has been fixed is discharged to the discharge tray 106 by the sheet discharge unit 110 and stacked. When forming an image on both sides of the sheet S, the sheet S is conveyed to the reverse conveyance unit 111, and a toner image is formed on the back surface of the sheet S in the same manner as described above.

[0022] [Process Cartridge] The process cartridge B will be described with reference to FIGS. 3 to 8. As shown in FIGS. 3 to 5, the process cartridge B includes a cleaning unit (first unit) 10 having a photosensitive drum 11, a cleaning blade 17, etc., and a developing unit (second unit) 15 having a developing roller 16. The cleaning unit 10 has a cleaning frame 20, and the developing unit 15 has a developing frame 24. The cartridge frame 75 constituting the process cartridge B includes, in addition to the cleaning frame 20 and the developing frame 24, bearing members 4 and 5, side covers 7, etc., which will be described later. The cleaning unit 10 has a photosensitive drum 11, a cleaning blade 17, a charging roller 12, a charging roller cleaner 14, a waste toner primary storage portion 10a, a first waste toner conveyance path 10b, and a second waste toner conveyance path 10c. The charging roller cleaner 14 is a cleaning member for the charging roller 12. The toner (waste toner) removed from the photosensitive drum 11 by the cleaning blade 17 is conveyed from the waste toner primary storage portion 10a to the toner cartridge C through the first waste toner conveyance path 10b and the second waste toner conveyance path 10c.

[0023] As shown in FIG. 6, the developing unit 15 includes a developing roller 16, a supply roller 13, a developing blade 18, a developing chamber 151, a developer storage chamber 152, and a toner receiving chamber 153. The developing roller 16 is disposed in the developing chamber 151. The developer storage chamber 152 supplies toner to the developing chamber 151. The toner receiving chamber 153 receives toner supplied from the toner cartridge C. The developing roller 16 rotates while carrying the toner and supplies the toner to the developing area of the photosensitive drum 11. Then, the developing roller 16 develops the electrostatic latent image formed on the photosensitive drum 11 using the toner. The supply roller 13 supplies the toner in the developing chamber 151 to the developing roller 16. Such a supply roller 13 is arranged so that the direction of its rotation axis is parallel to the direction of the rotation axis of the developing roller 16, and an elastic layer such as a sponge is formed on the outer peripheral surface so that the developer can be easily conveyed. The developing blade 18 abuts against the circumferential surface of the developing roller 16 and defines the amount of toner adhering to (carried on) the circumferential surface of the developing roller 16. Also, frictional charging charges are imparted to the toner.

[0024] The developer storage chamber 152 communicates with the developing chamber 151 and stores the toner to be supplied to the developing chamber 151. The toner stored in the developer storage chamber 152 is sent out to the developing chamber 151 by the rotation of the stirring member 154 and supplied to the developing roller 16. The remaining amount of the toner in the developer storage chamber 152 is detected by a remaining amount detection unit (not shown). Then, when the amount of toner in the developer storage chamber 152 becomes below a certain level, toner is supplied from the toner cartridge C to the process cartridge B.

[0025] The toner receiving chamber 153 communicates with the developer storage chamber 152 and supplies the toner replenished from the toner cartridge C to the developer storage chamber 152. The supply of toner from the toner cartridge C to the developing unit 15 of the process cartridge B is performed via the replenishing port 21c at the stage 21, the toner receiving chamber 153, and the transfer port 21d, and is stored in the developer storage chamber 152.

[0026] Next, with reference to FIGS. 4, 7(a), 7(b), 8(a), and 8(b), the configuration of the process cartridge B will be described in more detail. As described above, the cleaning unit 10 includes a photosensitive drum 11, a charging roller 12, and a cleaning blade 17. Similarly, the developing unit 15 includes a developing roller 16, a developing blade 18, a developing chamber 151, a developer storage chamber 152, and a toner receiving chamber 153.

[0027] As shown in FIGS. 7(a) and 7(b), the cleaning unit 10 is composed of a cleaning frame 20, which is a part of the cartridge frame 75, a stay 21, and a side cover 7. The cleaning frame 20 supports the cleaning blade 17, the charging roller 12, and the charging roller cleaner 14. As shown in FIG. 7(b), the photosensitive drum 11 is rotatably supported by a drum pin 22 attached to the cleaning frame 20 on one side and a photosensitive drum support portion 7b provided on the side cover 7 on the other side.

[0028] Also, as shown in FIGS. 7(a) and 7(b), bearing members 4 and 5 are arranged at the axial ends of the developing roller 16 in the rotational axis direction. The developing unit 15 is coupled to the cleaning unit 10 so as to be rotatable about a rocking axis 8 defined by a straight line including a support shaft 8a and a support shaft 8b. The rocking axis 8 is arranged substantially parallel to the rotational axis 11b of the photosensitive drum 11.

[0029] The configuration in which the developing unit 15 is supported by the cleaning unit 10 will be described in detail. As shown in FIG. 7(a), a cylindrical portion 5a provided on a bearing member 5, which is a part of the cartridge frame 75, is supported by a cylindrical hole portion 7a provided on a side cover 7, which is a part of the cartridge frame 75 of the cleaning unit 10. The support shaft 8a is defined by the common axis of the cylindrical hole portion 7a of the side cover 7 and the cylindrical portion 5a of the bearing member 5. Further, a developing coupling 155, as a drive input member for receiving drive from the apparatus main body A, is provided at the center of rotation of the cylindrical portion 5a of the bearing member 5.

[0030] Also, as shown in FIG. 7(b), the pin 6 is inserted so as to straddle the cylindrical hole portion 20a of the cleaning frame body 20 of the cleaning unit 10 and the cylindrical hole portion 4a of the bearing member 4 which is a part of the cartridge frame body 75. The support shaft 8b is defined by the common axis of the pin 6 and the cylindrical hole portion 4a of the bearing member 4. The support shaft 8a and the support shaft 8b are arranged substantially coaxially, and the swing axis 8 is defined by a straight line including the support shaft 8a and the support shaft 8b as described above.

[0031] As described above, the developing unit 15 is supported by the cleaning unit 10 so as to be rotatable about the swing axis 8. The developing unit 15 is biased toward the photosensitive drum 11 of the cleaning unit 10 by the pressing springs 19a and 19b which are elastic members, and the developing roller 16 abuts against the photosensitive drum 11.

[0032] Next, with respect to the contact and separation operation of the developing unit 15 with respect to the cleaning unit 10, it will be described with reference to FIGS. 8(a) and 8(b). FIGS. 8(a) and 8(b) are explanatory views in which the side cover 7 is omitted to show the separation mechanism 100 of the apparatus main body A. As shown in FIG. 8(a), in the bearing member 5, a convex portion 5b is provided at a position facing the separation mechanism 100. In the first embodiment, with the process cartridge B mounted on the apparatus main body A, the separation mechanism 100 is provided below the developing unit 15. The convex portion 5b is provided at the lower end portion of the bearing member 5. The separation mechanism 100 is provided in the apparatus main body A and is swingable substantially in the vertical direction about the swing shaft 100a by a drive source such as a motor (not shown).

[0033] As shown in FIG. 8(a), when the convex portion 5b is not in contact with the separation mechanism 100, the developing roller 16 abuts against the photosensitive drum 11 by the biasing force of the pressing springs 19a and 19b. This position is an image forming position where the electrostatic latent image formed on the surface of the photosensitive drum 11 can be developed by the developing roller 16.

[0034] As shown in FIG. 8(b), the separation mechanism 100 provided in the apparatus main body A swings about the swing shaft 100a and abuts against the convex portion 5b. When the convex portion 5b receives a force from the separation mechanism 100, the developing unit 15 rotates in the direction of arrow R2 about the swing axis 8 as the rotation center. As a result, the developing roller 16 separates from the photosensitive drum 11 against the biasing forces of the pressure springs 19a and 19b. This position becomes the non-image forming position retracted from the image forming position.

[0035] When the separation mechanism 100 returns from the position shown in FIG. 8(b) (separation position, non-image forming position) to the position shown in FIG. 8(a) (contact position, image forming position) which is the original position, the separation mechanism 100 separates from the convex portion 5b. Then, due to the biasing forces of the pressure spring 19a and the pressure spring 19b, the developing roller 16 comes into contact with the photosensitive drum 11 again. Thus, in the first embodiment, the position of the developing unit 15 can be switched between the contact position (image forming position) and the separation position (non-image forming position) by the separation mechanism 100. That is, the posture of the developing unit 15 in the process cartridge B can be switched between the contact position and the separation position with respect to the photosensitive drum 11. Thereby, deterioration of the toner can be suppressed and unnecessary toner consumption during non-image formation can be suppressed.

[0036] As described above, the developing unit 15 is configured to move between the contact position and the separation position by rotating about the swing axis 8 with respect to the cleaning unit 10. Therefore, when the developing unit 15 moves between the contact position and the separation position with respect to the cleaning unit 10, the change in the position of the developing coupling 155 can be suppressed to be very small, about the fitting play. Specifically, the cylindrical portion 5a of the bearing member 5 engages with the cylindrical hole portion 7a of the side cover 7 (FIG. 7(a)), but the cylindrical portion 5a of the bearing member 5 and the cylindrical hole portion 7a of the side cover 7 engage with a fitting play within 0.13 mm. Therefore, the position of the developing coupling 155 when the developing unit 15 moves between the contact position and the separation position does not change by more than the fitting play.

[0037] [Toner Cartridge] Next, the toner cartridge C will be described with reference to FIGS. 9 to 12. As shown in FIG. 9, the toner cartridge C includes a toner supply unit 30 and a waste toner storage unit 40. The toner cartridge C is detachable from the apparatus main body A together with the process cartridge B, and is also detachable from the process cartridge B. The toner supply unit 30 can supply toner to the process cartridge B. The waste toner storage unit 40 can store the waste toner collected by the process cartridge B.

[0038] [Toner Supply Unit] As shown in FIG. 10, the toner supply unit 30 has a toner supply container 31 as a first storage container for storing toner, and a toner discharge port 31a for discharging toner from the toner supply container 31 to the outside. The toner supply container 31 is formed of a supply unit frame body 32a having a toner storage portion 30a and a supply unit lid 32b. Further, the supply unit frame body 32a has a toner discharge port 31a for discharging toner from the toner storage portion 30a. Also, a shutter member 34 capable of opening and closing the toner discharge port 31a is provided. The shutter member 34 opens and closes the toner discharge port 31a by rotating in the direction of arrow R1 in conjunction with the attachment / detachment operation of the toner cartridge C with respect to the process cartridge B. The shutter member 34 is disposed outside the supply unit frame body 32a.

[0039] Further, the toner storage portion 30a has a toner storage portion screw member 35 as a toner transport member for transporting toner to the toner discharge port 31a, which transports toner toward the toner discharge port 31a. Also, it has a toner storage portion agitation transport unit 36 for transporting toner toward the toner storage portion screw member 35.

[0040] Also, as shown in FIGS. 12(a) and 12(b), the toner conveyed to the toner discharge port 31a is discharged outside the toner discharge port 31a due to the volume change of the pump 37a provided in the pump unit 37. The pump unit 37 is composed of a pump 37a that changes its volume by expanding and contracting, a cam 37b that expands and contracts the pump 37a by rotation, and a link arm 37c. Also, as shown in FIGS. 8(a), 8(b), 12(a), and 12(b), the toner supply unit 30 has a stirring drive input unit 38 and a pump-screw drive input unit 39 as a toner conveyance drive unit that drives the toner conveyance unit. The stirring drive input unit 38 drives the toner storage unit stirring and conveyance unit 36, and the pump-screw drive input unit 39 drives the pump unit 37 and the toner storage unit screw member 35. A rotational driving force is input to the pump-screw drive input unit 39 from the apparatus main body A via a pump-screw coupling part 39a having a protrusion shape. This rotational driving force is converted into a reciprocating motion by the cam 37b and the link arm 37c. Then, by using this reciprocating motion to expand and contract the bellows shape of the pump 37a, a volume change is obtained.

[0041] [Waste Toner Storage Unit] As shown in FIG. 11, the waste toner storage unit 40 has a waste toner inlet 42 for receiving waste toner from the process cartridge B and a waste toner storage container 41 as a second storage container for storing the waste toner received from the waste toner inlet 42.

[0042] The waste toner storage container 41 is formed by a waste toner storage unit frame body 41a having a waste toner storage unit 40a and a waste toner lid 41b. The waste toner lid 41b is provided with a waste toner inlet 42 for receiving waste toner recovered from the process cartridge. The waste toner lid 41b has a waste toner shutter member 43 for opening and closing the waste toner inlet 42. The waste toner shutter member 43 is opened and closed in the direction of arrow R3 in FIG. 11 in conjunction with the attachment and detachment of the toner cartridge C to and from the apparatus main body A.

[0043] As shown in FIGS. 11 and 12(a), inside the waste toner container unit 40, there are a partition member 46, a first waste toner storage screw 44 as a waste toner conveying member for conveying the waste toner in the waste toner storage section 40a, and a second waste toner storage screw 45. The partition member 46 partitions the space inside the waste toner container unit 40 into a plurality of storage sections. The first waste toner storage screw 44 conveys the waste toner that has fallen from the waste toner inlet 42 in the longitudinal direction of the toner cartridge C. The second waste toner storage screw 45 obtains driving force from the first waste toner storage screw 44 and conveys the waste toner conveyed by the first waste toner storage screw 44 obliquely upward.

[0044] As shown in FIGS. 12(a) and 12(b), the driving force input from the aforementioned stirring driving input section 38 is transmitted to the non-driven side of the toner supply unit 30 via the toner storage section stirring and conveying unit 36 and is transmitted to the non-driven side gear 38a of the toner storage section stirring member. From the non-driven side gear 38a of the toner storage section stirring member, the driving force is transmitted to the first waste toner storage screw 44 through the waste toner storage section gear train 47. A driving side toner cartridge side cover 50 is attached to the toner supply unit 30 side, and a non-driven side toner cartridge side cover 600 is attached to the waste toner container unit 40 side, respectively.

[0045] With the above configuration, even when the pump-screw driving input section 39 is not being driven, the stirring driving input section 38 can be driven. That is, even when the toner supply unit 30 is not supplying toner to the process cartridge B, the first waste toner storage screw 44 and the second waste toner storage screw 45 inside the waste toner container unit 40 can be driven to maintain a state where waste toner can be recovered.

[0046] In addition, since the drive input from the apparatus main body A can be applied to one end of the toner cartridge C, the gear train of the apparatus main body A can be simplified. Further, by using the toner storage unit agitation and conveyance unit 36 to transmit the drive from one end to the other end of the supply unit frame body 32a, the drive can be transmitted to the waste toner storage unit 40 without increasing the components for drive transmission. As a result, while suppressing the increase in size in the rotational axis direction of the toner cartridge C and the photosensitive drum 11 of the apparatus main body A due to the drive means of the toner cartridge C, waste toner can be stored in the toner cartridge C.

[0047] [Explanation of the shutter unit] The configuration of the shutter unit 60 will be described with reference to FIGS. 1, 13, and 14. In the following description, the rotational axis direction of the photosensitive drum 11 is defined as the first direction X, the side where the developing coupling 155 is provided is defined as the drive side, and the opposite side is defined as the non-drive side. The drive side is the upstream side in the first direction, and the non-drive side is the downstream side in the first direction. FIG. 1(a) is a bottom view of the drive side of the process cartridge B in a state where the shutter unit 60 is in the shielding position, and FIG. 1(b) is a side view of the process cartridge B in a state where the shutter unit 60 is in the shielding position as viewed from the drive side. FIG. 13(a) is a bottom view of the non-drive side of the process cartridge B in a state where the shutter unit 60 is in the shielding position, and FIG. 13(b) is a side view of the process cartridge B in a state where the shutter unit 60 is in the shielding position as viewed from the non-drive side. FIG. 14 is a perspective view of the shutter unit 60.

[0048] As shown in FIGS. 1, 13, 14, and 16(a), the drum unit 70 includes a photosensitive drum 11 and a drum gear 71. The photosensitive drum 11 is rotatable with the first direction X as the rotational axis direction. The drum gear 71 is a drive portion provided at the drive side end portion (the upstream end portion in the first direction X) of the photosensitive drum 11. In the first direction X, the side where the drum gear 71, which is the drive portion of the photosensitive drum 11, is provided is the drive side, and the side where the drum gear 71 is not provided is the non-drive side. The drum unit 70 is attached to the cleaning frame body 20 on the non-drive side It is rotatably supported by a driving-side drum pin 22 (see FIG. 7(b)) on a photosensitive drum support portion 7b (see FIG. 7(b)) provided on the side cover 7. The drum gear 71 receives driving force from a drum driving gear (not shown) provided in the apparatus main body A and rotates the photosensitive drum 11.

[0049] As shown in FIG. 4, the cartridge frame 75 has an opening 23 that opens in a second direction Y intersecting the first direction X. The cartridge frame 75 is configured such that a part of the circumferential direction (the rotation direction around the first direction X) of the drum unit 70 having the photosensitive drum 11 and the drum gear 71 is exposed from the opening 23. Therefore, in the opening 23, a part of the circumferential direction of the photosensitive drum 11 and the drum gear 71 is exposed. The side facing outward from the inside of the cartridge frame 75 through the opening 23 is defined as the downstream side in the Y direction.

[0050] The shutter unit 60 includes a link member 61, a shutter member 62, and an arm member 63.

[0051] The shutter member 62 is located downstream of the photosensitive drum 11 among the photosensitive drum 11 and the drum gear 71 exposed from the opening 23 in the second direction Y, and shields the surface of the exposed portion of the photosensitive drum 11. The shutter member 62 does not shield the surface of the drum gear 71 among the photosensitive drum 11 and the drum gear 71 exposed from the opening 23. The link member 61 is rotatably supported by the cartridge frame 75 around the rotation axis E parallel to the first direction, and the shutter member 62 is attached thereto, connecting the cartridge frame 75 and the shutter member 62. The shutter member 62 rotates around an axis parallel to the first direction X by the rotation of the link member 61. Thereby, the shutter member 62 can move between a shielding position (FIGS. 1, 13, 15) that shields the portion exposed from the opening 23 of the photosensitive drum 11 and an open position (FIGS. 16, 17) that does not shield the exposed portion. Hereinafter, in the range where the shutter member 62 can move from the shielding position to the open position, the direction from the shielding position to the open position is defined as the positive direction of the third direction R4. In the range where the shutter member 62 can move, the side where the shielding position is located is the upstream side in the third direction R4, and the side where the open position is located is the downstream side in the third direction R4. The third direction R4 is a direction that rotates around the first direction X and intersects (perpendicular in the first embodiment) the second direction Y.

[0052] The link member 61 has a first link portion 611, a second link portion 612, and a connected portion 61a that is a connecting portion connecting these, and the first link portion 611 and the second link portion 612 rotate integrally. The first link portion 611 is rotatably supported by a link member support portion 5c (see FIG. 1(b)) of the bearing member 5 which is a portion on the driving side (upstream side) in the first direction X of the cartridge frame 75. The second link portion 612 is a second link member rotatably supported by a link member support portion 4c of the bearing member 4 provided on the non-driving side of the developing unit 15 which is a portion on the non-driving side (downstream side) in the first direction X of the cartridge frame 75. The connected portion 61a extends in a direction parallel to the first direction X. Here, the link member support portion 4c of the bearing member 4 and the link member support portion (not shown) of the bearing member 5 are at the same position when viewed in the first direction X. Therefore, the link member 61 is rotatable around the rotation axis E.

[0053] The shutter member 62 extends in the first direction X. The first link portion 611 is attached to the portion of the shutter member 62 on the driving side (upstream side) in the first direction X. The second link portion 612 is attached to the portion of the shutter member 62 on the non-driving side (downstream side) in the first direction X. The connecting portion 62a between the link member 61 and the shutter member 62 is located in the portion of the shutter member 62 on the side (downstream side) closer to the open position in the positive direction of the third direction R4 in a state where the shutter member 62 is in the shielding position. The connecting portion 62a of the shutter member 62 is rotatably connected to the connected portion 61a of the link member 61. That is, the shutter member 62 is rotatably connected to the link member 61.

[0054] Further, the arm member 63 is a third link member that is rotatably supported by the arm member support portion 4b of the bearing member 4, which is the portion of the cartridge frame body 75 on the non-driving side (downstream side) in the first direction X. The arm member 63 is attached to an arm member connecting portion 62b provided in the portion of the shutter member 62 on the non-driving side (downstream side) in the first direction X (non-driving side end portion). The arm member connecting portion 62b, which is the connecting portion between the arm member 63 and the shutter member 62, is located at a position (upstream side) farther in the negative direction of the third direction R4 than the connecting portion 62a between the second link portion 612 of the link member 61 and the shutter member 62.

[0055] One end of the arm member 63 is provided with a shutter member connecting portion 63a, and the other end is provided with a cartridge frame body connecting portion 63b. The cartridge frame body connecting portion 63b is rotatably supported by the arm member support portion 4b of the bearing member 4 provided in the non-driving side portion of the developing unit 15 in the first direction X. The shutter member connecting portion 63a is rotatably supported by the arm member connecting portion 62b of the shutter member 62.

[0056] The arm member connecting portion 62b is provided at a position (upstream side) away from the connecting portion 62a in the negative direction of the third direction R4, and the arm member support portion 4b is provided at a position (upstream side) away from the link member support portion 4c in the negative direction of the third direction R4. Therefore, the arm member 63 is provided at a position (upstream side) away from the link member 61 in the negative direction of the third direction R4. Note that the arm member 63 has a role of determining the posture of the shutter member 62 that is rotatably connected to the link member 61.

[0057] Next, with reference to FIGS. 1 and 13 to 18, the configuration of the shutter unit 60 in the shielded position and the open position will be described. FIG. 15(a) is a side view of the process cartridge B viewed from the driving side in the first direction X with the shutter unit 60 in the shielded position. FIG. 15(b) is a diagram showing the projection of the protruding portion 61b and the drum gear 71 onto a virtual plane perpendicular to the second direction Y with the shutter unit 60 in the shielded position. FIG. 16(a) is a bottom view of a portion of the process cartridge B on the driving side in the first direction X with the shutter unit 60 in the open position. FIG. 16(b) is a side view of the process cartridge B viewed from the driving side in the first direction X with the shutter unit 60 in the open position. FIG. 17(a) is a bottom view of a portion of the process cartridge B on the non-driving side in the first direction X with the shutter unit 60 in the open position. FIG. 17(b) is a side view of the process cartridge B viewed from the non-driving side in the first direction X with the shutter unit 60 in the open position. FIG. 18 is a diagram showing the superposition of the state where the shutter unit 60 is in the shielded position and the open position, and is a side view of the process cartridge B viewed from the driving side in the first direction X with the side cover 7 not shown.

[0058] The shutter member 62 is movable in a third direction R4 between a shielding position that covers the photosensitive drum 11 and an open position that exposes the photosensitive drum 11 in accordance with the rotational movements of the link member 61 and the arm member 63. In the range where the shutter member 62 is movable, the direction from the shielding position toward the open position is defined as the positive direction of the third direction R4. As shown in FIG. 16(b), in this embodiment, the range where the shutter member 62 is movable is the range from the shielding position to the open position by rotating clockwise. When viewed in the first direction X, clockwise is the positive direction of the third direction R4, and counterclockwise is the negative direction of the third direction R4.

[0059] Using FIGS. 1 and 13, the case where the shutter member 62 is in the shielding position will be described. As shown in FIG. 1, in the state where the shutter member 62 is in the shielding position, the shutter member 62 is disposed at a position that covers the photosensitive drum 11. At this time, of the photosensitive drum 11, the drum gear 71 provided at the driving-side end in the first direction X is not covered by the shutter member 62. Also, in the first direction X, at least a part of the drum gear 71 overlaps at least a part of the convex portion 5b of the bearing member 5 and, of the shutter member 62, the driving-side end in the first direction X is provided inside the convex portion 5b of the bearing member 5.

[0060] The link member 61 has a first portion 61f that extends from the connecting portion 62a in the first direction X from the non-driving side to the driving side (upstream side) to the outside of the shutter member 62. The first portion 61f has a portion 61e that extends in the first direction X and a protruding portion 61b that protrudes from the portion 61e that extends in the first direction X toward the negative direction side (upstream side) of the third direction R4. As shown in FIGS. 15(a) and 15(b), in a state where the shutter member 62 is in the shielding position, a projection S1 of the protruding portion 61b onto a virtual plane V perpendicular to the second direction Y at least partially overlaps a projection S2 of the drum gear 71 onto the virtual plane V. In other words, as shown in FIG. 15(b), the protruding portion 61b is provided at a position where it at least partially overlaps the drum gear 71 in the first direction X and at least partially overlaps the drum gear 71 when viewed in the second direction Y. The protruding portion 61b protrudes from the connecting portion 62a toward the negative direction side (upstream side) of the third direction R4. As a result, the protruding portion 61b protrudes toward the side that covers the photosensitive drum 11 in a state where the shutter member 62 is in the shielding position. Therefore, in a state where the shutter member 62 is in the shielding position, the protruding portion 61b covers a part of the drum gear 71.

[0061] Also, as shown in FIG. 13, a biasing member 64 that biases the shutter unit 60 in the negative direction of the third direction R4 (the direction toward the shielding position) is provided on the bearing member 4 on the non-driving side in the first direction X. The biasing member 64 applies a force to move the shutter member 62 in the negative direction of the third direction R4 (the direction toward the shielding position) with respect to the link member 61. In the first embodiment, the biasing member 64 is a torsion coil spring, and by biasing the link member 61 in the negative direction of the third direction R4 (the direction toward the shielding position), the shutter member 62 is biased in the negative direction of the third direction R4 (the direction toward the shielding position). Therefore, while the process cartridge B is not mounted on the apparatus main body A, the shutter member 62 is maintained in the shielding position. By providing the biasing member 64 on the same side as the arm member 63, the shutter member 62 can be stably operated.

[0062] With reference to FIG. 15, the state where the process cartridge B is removed from the apparatus main body A will be described. In a state where the shutter member 62 is in the shielding position, when viewed in the first direction X, the portion of the protruding portion 61b that most protrudes in the negative direction (upstream side) of the third direction R4 is defined as the most protruding portion 61d. A straight line L connecting this most protruding portion 61d and the side cover 7 is located at a position separated from the drum gear 71 by a distance d1. As a result, when the process cartridge B is placed on a desk or the like in a posture such that the shutter member 62 faces downward, the protruding portion 61b (the most protruding portion 61d) and the side cover 7 come into contact with the surface of the desk or the like. Then, the drum gear 71 will be separated from the surface of the desk or the like by a distance d1 and will not contact the surface of the desk or the like. The straight line L can be said to be a virtual plane including the downstream end portion of the protruding portion 61b in the second direction Y and the downstream end portion in the second direction Y of the portion outside the passage region of the shutter member 62 in the first direction X of the cartridge frame body 75. Since this virtual plane is separated from the drum gear 71 in the second direction Y, even when the process cartridge B is placed on a desk or the like, it is possible to suppress the drum gear 71 not covered by the shutter member 62 from contacting the desk or the like. In the posture where the shutter member 62 faces downward as shown in FIG. 15(a), the second direction Y is a vertically downward direction or a direction having a vertically downward component.

[0063] Next, with reference to FIGS. 16 and 17, the case where the shutter member 62 is in the open position will be described. During the process of mounting the process cartridge B to the apparatus main body A, the link member 61 engages with an engaging portion 300 (see FIG. 2) provided on the apparatus main body A. As a result, the link member 61 and the arm member 63 are rotated and receive a force to move the shutter member 62 in the positive direction of the third direction R4. Thereby, the shutter member 62 moves to the open position. Regarding this movement locus, when viewed in the first direction X, the shutter member 62 moves from a position not overlapping with the bearing member 5 (see FIG. 1(b)) to a position overlapping with the bearing member 5. That is, the shutter member The opening and closing locus along which the shutter member 62 moves from the shielding position to the open position intersects the bearing member 5, and the convex portion 5b provided on the bearing member 5 protrudes beyond the opening and closing locus of the shutter member 62. Thus, outside the passage region of the shutter member 62 in the first direction X in the cartridge frame 75, there is a portion that overlaps the passage region when viewed in the first direction X. However, the size of the shutter member 62 in the first direction X is equal to or less than the size of the photosensitive drum 11 in the first direction X in the drum unit 70, and the driving side end portion of the shutter member 62 in the first direction X is provided inside the convex portion 5b of the bearing member 5. Therefore, the shutter member 62 and the bearing member 5 do not interfere with each other.

[0064] Here, the protruding portion 61b of the link member 61 overlaps with the convex portion 5b of the bearing member 5 in the first direction X. Also, the distance a3 from the rotation center 61c of the link member 61 to the convex portion 5b is farther than the distance a1 from the rotation center 61c to the connecting portion 62a and the connected portion 61a of the link member 61. Therefore, since the radii of rotation of the connecting portion 62a and the connected portion 61a are smaller than the distance a3 from the rotation center 61c to the convex portion 5b, the connecting portion 62a and the connected portion 61a are in a positional relationship where they interfere with the convex portion 5b. However, as described above, the driving-side end portion of the shutter member 62 in the first direction X is provided inside the convex portion 5b of the bearing member 5. Therefore, the shutter member 62 and the bearing member 5 do not interfere, and the connecting portion 62a and the connected portion 61a do not interfere with the convex portion 5b. On the other hand, as shown in FIGS. 1(a) and 16(a), in the first direction X, the protruding portion 61b of the link member 61 is provided at a position overlapping with the convex portion 5b of the bearing member 5. However, since the protruding portion 61b protrudes in the negative direction (upstream side) of the third direction R4, the distance a2 from the rotation center 61c is farther than the distance a1 from the rotation center 61c to the connecting portion 62a and the connected portion 61a. As a result, in the movement of the shutter member 62 from the shielding position to the open position (or from the open position to the shielding position), the radius of rotation of the protruding portion 61b becomes larger than the radii of rotation of the connecting portion 62a and the connected portion 61a. Also, the protruding portion 61b is provided such that the distance a2 from the rotation center 61c of the protruding portion 61b is larger than the distance a3 from the rotation center 61c to the convex portion 5b. For this reason, the radius of rotation of the protruding portion 61b becomes larger than the distance a3 from the rotation center 61c to the convex portion 5b, and interference between the protruding portion 61b and the convex portion 5b of the bearing member 5 can be avoided in the opening and closing locus of the shutter member 62.

[0065] Also, as described above, the connecting portion 62a is provided in a portion on the positive direction side (downstream side) in the third direction R4 of the shutter member 62 in a state where the shutter member 62 is in the shielding position. In the present embodiment, the connecting portion 62a is provided at the end portion on the positive direction side in the R4 direction of the region on the positive direction side (downstream side) in the third direction R4 of the shutter member 62. As shown in FIG. 18, when viewed in the first direction X, in a state where the shutter member 62 is in the shielding position, the connecting portion 62a is on the side of the line segment L1 connecting the rotation center 61c of the link member 61 and the rotation center 70a of the drum unit 70. That is, the intersection of the straight line passing through the rotation center 61c of the link member 61 and the rotation center 70a of the drum unit 70 and the perpendicular line dropped from the connecting portion 62a to the straight line in a state where the shutter member 62 is in the shielding position is between the rotation center 61c and the rotation center 70a. Further, the connecting portion 62a is arranged such that the line segment L2 is longer than the line segment L3. Here, the line segment L2 is a line segment connecting the connecting portion 62a and the rotation center 61c of the link member 61 in a state where the shutter member 62 is in the shielding position. The line segment L3 is a line segment connecting the connecting portion 62a and the rotation center 70a of the drum unit 70 in a state where the shutter member 62 is in the shielding position. With this configuration, it is possible to reduce the opening / closing locus D1 of the connecting portion 62a when the shutter member 62 moves from the shielding position to the open position.

[0066] As an example of a comparison target, a case where the connecting portion 62a is provided in a portion on the negative direction side (upstream side) in the third direction R4 of the shutter member 62 in a state where the shutter member 62 is in the shielding position is shown. For example, it is a case where the connecting portion 62a is at the end portion on the negative direction side (upstream side) in the third direction R4 of the shutter member 62. In FIG. 18, the shutter member 62 having such a configuration is shielded Shows the opening and closing locus D2 of the connecting part 62a when moving from the shielding position to the open position. The radius of the opening and closing locus D2 is larger than the radius of the opening and closing locus D1 (D2 > D1). For such a configuration, in this embodiment, since the opening and closing locus D1 of the shutter member 62 can be reduced, it leads to miniaturization of the product. Also, when the connecting part 62a is provided in the positive direction side of the shutter member 62 in the third direction R4, the moving amount of the connecting part 62a when moving from the shielding position to the open position is smaller than the moving amount when the connecting part 62a is provided in the negative direction side of the third direction R4. Thereby, the shutter member 62 can operate stably. Also, by arranging the line segment L2 to be longer than the line segment L3, since the connecting part 62a is provided at a position close to the photosensitive drum 11, the photosensitive drum 11 can be covered with a small shutter member 62. Therefore, it leads to miniaturization of the shutter member 62 and the product.

[0067] According to the configuration shown above, the protruding part 61b provided on the link member 61 can protect the drum gear 71 which is a driving part for driving the photosensitive drum 11. Specifically, in a state where the shutter member 62 is in the shielding position, since the protruding part 61b is configured to cover a part of the drum gear 71, it is possible to prevent the user from touching the drum gear 71. Thereby, it is possible to prevent the drum gear 71 from being scratched or dented.

[0068] In addition, when viewed in the first direction X, the straight line L (see FIG. 15) connecting the most protruding part 61d and the cartridge frame 75 (side cover 7) is at a position separated from the drum gear 71 by a distance d1. Thereby, even when the process cartridge B is removed from the apparatus main body A and placed on a desk or the like, since the drum gear 71 is configured not to contact the desk or the like, it is possible to suppress the drum gear 71 from contacting the desk or the like and being scratched or dented.

[0069] All of the above-described content is configured to protect the drum gear 71 by the protruding portion 61b provided on the link member 61 that is necessary for the operation of the shutter member 62 that protects the photosensitive drum 11. Therefore, the drum gear 71 can be protected without providing a separate member for protecting the drum gear 71, leading to cost reduction.

[0070] In addition, when viewed in the first direction X, the connecting portion 62a is on the side of the line segment L1 connecting the rotation center 61c of the link member 61 and the rotation center 70a of the drum unit 70. That is, when a perpendicular line is drawn from the connecting portion 62a in a state where the shutter member 62 is in the shielding position to the straight line passing through the rotation center 61c of the link member 61 and the rotation center 70a of the drum unit 70, the intersection point is between the rotation center 61c and the rotation center 70a. Further, the connecting portion 62a is arranged such that the line segment L2 connecting the connecting portion 62a and the rotation center 61c of the link member 61 is longer than the line segment L3 connecting the connecting portion 62a and the rotation center 70a of the drum unit 70 (L2 > L3). With this configuration, the opening and closing locus of the shutter member 62 can be reduced, leading to miniaturization of the process cartridge B. Also, since the connecting portion 62a is provided at a position close to the photosensitive drum 11, the photosensitive drum 11 can be covered with a small shutter member 62. Thus, it leads to miniaturization of the shutter member 62 and the process cartridge B.

[0071] In addition, it is configured to protect the drum gear 71 by the link member 61 instead of the shutter member 62 that protects the photosensitive drum 11. Thereby, it is possible to prevent grease or the like used for the drum gear 71 from being transmitted through the shutter member 62 and adhering to the photosensitive drum 11.

[0072] Also, Example 1 can be applied to an apparatus main body that enables the process cartridge to be detachable, and the same effects can be obtained. The functions, materials, shapes, and relative arrangements of the component parts described in Example 1 are not intended to limit the scope of this invention only to those, unless otherwise specifically described.

[0073] The disclosure of this embodiment includes the following configurations. (Configuration 1) A process cartridge detachable from the main body of an image forming apparatus, a drum unit having a photosensitive drum rotatable with the first direction as the rotation axis direction and a drive unit provided at an end of the photosensitive drum in the first direction, a frame body rotatably supporting the drum unit, the frame body having an opening opening in a second direction intersecting the first direction, and configured such that a part of the circumferential direction of the drum unit is exposed from the opening, a shutter member positioned downstream in the second direction with respect to the photosensitive drum exposed from the opening, the shutter member shielding the surface of the photosensitive drum among the part exposed from the opening of the drum unit, With a direction of rotation around an axis parallel to the first direction and intersecting the second direction as a third direction, it is supported by the frame body rotatably in the third direction, the shutter member is attached thereto, and a link member connecting the frame body and the shutter member, having, The shutter member is movable in the third direction between a shielding position where the shutter member rotates by the rotation of the link member and shields the exposed portion of the photosensitive drum and an open position where the exposed portion of the photosensitive drum is not shielded, In the first direction, the side where the drive unit of the photosensitive drum is provided is the drive side, the side where the drive unit is not provided is the non-drive side, and in the third direction, the direction from the shielding position to the open position within the range where the shutter member is movable is the positive direction, The link member is rotatably supported by a portion of the frame body on the drive side in the first direction and is attached to a portion of the shutter member on the drive side in the first direction, A connecting portion between the link member and the shutter member is located at a portion on the positive direction side in the third direction of the shutter member in a state where the shutter member is in the shielding position, The link member has a first portion that extends from the connecting portion to the outside of the shutter member in the first direction from the non-driving side to the driving side. In a state where the shutter member is in the shielding position, the first portion at least partially overlaps with the driving portion in the first direction, and at least partially overlaps with the driving portion when viewed in the second direction. A process cartridge characterized by this. (Configuration 2) The first portion has a portion extending in the first direction and a portion protruding from the portion extending in the first direction to the negative direction side in the third direction in a state where the shutter member is in the shielding position. The process cartridge according to Configuration 1. (Configuration 3) Among the frame bodies, a second link member that is rotatably supported by a portion on the non-driving side in the first direction and is attached to a portion on the non-driving side in the first direction of the shutter member. The process cartridge according to Configuration 1 or 2. (Configuration 4) It has a connecting portion that connects the link member and the second link member, and the link member and the second link member rotate integrally. The process cartridge according to Configuration 3. (Configuration 5) Among the frame bodies, a third link member that is rotatably supported by a portion on the non-driving side in the first direction and is attached to a portion on the non-driving side in the first direction of the shutter member. In a state where the shutter member is in the shielding position, the connecting portion between the third link member and the shutter member is located farther in the negative direction of the third direction than the connecting portion between the second link member and the shutter member. The process cartridge according to Configuration 3 or 4. (Configuration 6) The size of the shutter member in the first direction is less than or equal to the size of the photosensitive drum in the first direction of the drum unit. In the frame body, outside the passage area of the shutter member in the first direction, there is a portion that overlaps the passage area when viewed in the first direction. The process cartridge according to any one of Configurations 1 to 5. (Configuration 7) In a state where the shutter member is in the shielding position, a virtual plane including the downstream end of the first portion in the second direction and the downstream end of the portion of the frame body outside the passage area of the shutter member in the first direction in the second direction is separated from the drive unit in the second direction. The process cartridge according to any one of Configurations 1 to 6. (Configuration 8) When viewed in the first direction, the intersection of the straight line passing through the rotation center of the link member and the rotation center of the drum unit and the perpendicular line drawn from the connection portion between the link member and the shutter member in a state where the shutter member is in the shielding position to the straight line is between the rotation center of the link member and the rotation center of the drum unit. The process cartridge according to any one of Configurations 1 to 7. (Configuration 9) The line segment connecting the rotation center of the link member and the connection portion between the link member and the shutter member in a state where the shutter member is in the shielding position is longer than the line segment connecting the rotation center of the drum unit and the connection portion in a state where the shutter member is in the shielding position. The process cartridge according to any one of Configurations 1 to 8. (Configuration 10) The link member receives a force to move the shutter member from the shielding position to the open position by engaging with an engaging portion provided on the apparatus main body during the process of mounting the process cartridge on the apparatus main body. The process cartridge according to any one of Configurations 1 to 9. (Configuration 11) The link member has a biasing member that applies a force to move the shutter member in the negative direction of the third direction. The process cartridge according to any one of Configurations 1 to 10.

Explanation of Reference Numerals

[0074] 11: Photosensitive drum, 23: Opening, 61: Link member, 611: First link part, 61b: Protrusion, 61f: First part, 62: Shutter member, 62a: Connection part, 70: Drum unit, 71: Drum gear, 75: Cartridge frame, A: Apparatus main body, B: Process cartridge, R4: Third direction, X: First direction, Y: Second direction

Claims

1. A process cartridge detachable from a main body of an image forming apparatus, comprising: a drum unit having a photosensitive drum rotatable about a first direction as a rotation axis direction, and a driving unit provided at an end of the photosensitive drum in the first direction; a frame rotatably supporting the drum unit, the frame having an opening that opens in a second direction intersecting the first direction, and being configured such that a part of the circumferential direction of the drum unit is exposed from the opening; a shutter member positioned downstream in the second direction with respect to the photosensitive drum exposed from the opening, the shutter member shielding a surface of the photosensitive drum among the part exposed from the opening of the drum unit; a link member rotatably supported by the frame in a third direction, which is a direction of rotation about an axis parallel to the first direction and intersects the second direction, the shutter member being attached thereto, and connecting the frame and the shutter member; wherein: the shutter member is movable in the third direction between a shielding position where the shutter member rotates by rotation of the link member and shields the exposed portion of the photosensitive drum, and an open position where the shutter member does not shield the exposed portion of the photosensitive drum; in the first direction, a side where the driving unit of the photosensitive drum is provided is defined as a driving side, and a side where the driving unit is not provided is defined as a non-driving side, and in the third direction, a direction from the shielding position to the open position within a range where the shutter member is movable is defined as a positive direction; the link member is rotatably supported by a portion of the frame on the driving side in the first direction, and is attached to a portion of the shutter member on the driving side in the first direction; a connecting portion between the link member and the shutter member is located at a portion on the positive direction side in the third direction of the shutter member in a state where the shutter member is in the shielding position; the link member has a first portion extending from the connecting portion to the outside of the shutter member in a direction from the non-driving side to the driving side in the first direction; in a state where the shutter member is in the shielding position, the first portion at least partially overlaps the driving unit in the first direction and at least partially overlaps the driving unit when viewed in the second direction. A process cartridge characterized by the above.

2. The first part has a portion extending in the first direction and a portion protruding from the portion extending in the first direction toward the negative side in the third direction in a state where the shutter member is in the shielding position. The process cartridge according to claim 1.

3. Among the frame bodies, a second link member that is rotatably supported by a portion on the non-driving side in the first direction and is attached to a portion on the non-driving side in the first direction of the shutter member. The process cartridge according to claim 1 or 2.

4. The process cartridge according to claim 3, having a connecting portion that connects the link member and the second link member, and the link member and the second link member rotate integrally.

5. Among the frame bodies, a third link member that is rotatably supported by a portion on the non-driving side in the first direction and is attached to a portion on the non-driving side in the first direction of the shutter member. In a state where the shutter member is in the shielding position, a connecting portion between the third link member and the shutter member is located further in the negative direction of the third direction than a connecting portion between the second link member and the shutter member. The process cartridge according to claim 3.

6. The size of the shutter member in the first direction is equal to or less than the size of the photosensitive drum in the first direction among the drum units. Outside the passing region of the shutter member in the first direction in the frame body, there is a portion that overlaps the passing region when viewed in the first direction. The process cartridge according to claim 1 or 2.

7. In a state where the shutter member is in the shielding position, a virtual plane including a downstream end portion of the first part in the second direction and a downstream end portion of a portion outside the passing region of the shutter member in the first direction of the frame body in the second direction is separated from the driving portion in the second direction. The process cartridge according to claim 1 or 2.

8. When viewed in the first direction, an intersection point between a straight line passing through the rotation center of the link member and the rotation center of the drum unit and a perpendicular line dropped from a connecting portion between the link member and the shutter member in a state where the shutter member is in the shielding position to the straight line is located between the rotation center of the link member and the rotation center of the drum unit. The process cartridge according to claim 1 or 2.

9. The line segment connecting the rotation center of the link member and the connection portion between the link member and the shutter member in a state where the shutter member is in the shielding position is longer than the line segment connecting the rotation center of the drum unit and the connection portion in a state where the shutter member is in the shielding position. The process cartridge according to claim 1 or 2.

10. The link member receives a force for moving the shutter member from the shielding position to the open position by engaging with an engaging portion provided on the apparatus main body in the process of mounting the process cartridge on the apparatus main body. The process cartridge according to claim 1 or 2.

11. The process cartridge according to claim 1 or 2, further comprising a biasing member that applies a force to move the shutter member in the negative direction of the third direction to the link member.

Images