JP2018180128A - Process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem in which a separation member easily removes, when a component in contact with a drum surface is separated too much and the holding power of the separation member is reduced.SOLUTION: A regulating part and a regulated part are provided that engage with each other, when a separation member performs a movement non-related to an assembling movement and to a separation releasing movement.SELECTED DRAWING: Figure 18

Description

  The present invention relates to a process cartridge and an image forming apparatus using the same. Here, the process cartridge is a cartridge integrally formed with the electrophotographic photosensitive drum and the process means acting on the electrophotographic photosensitive drum, and is detachably mounted to the main body of the electrophotographic image forming apparatus. It is a thing.

  For example, one in which at least one of an electrophotographic photosensitive drum and a developing unit, a charging unit, and a cleaning unit as the process unit are integrally formed into a cartridge can be mentioned. The electrophotographic image forming apparatus is an apparatus for forming an image on a recording medium using an electrophotographic image forming method.

  Examples of the electrophotographic image forming apparatus include, for example, an electrophotographic copying machine, an electrophotographic printer (LED printer, laser beam printer, etc.), a facsimile machine, a word processor, and the like.

  In an electrophotographic image forming apparatus (hereinafter, also simply referred to as "image forming apparatus"), an electrophotographic photosensitive member generally made into a drum shape as an image carrier, that is, an electrophotographic photosensitive drum is uniformly charged. Next, an electrostatic latent image (electrostatic image) is formed on the electrophotographic photosensitive drum by selectively exposing the charged electrophotographic photosensitive drum. Then, the electrostatic latent image formed on the electrophotographic photosensitive drum is developed as a toner image with a toner as a developer. Then, the toner image formed on the electrophotographic photosensitive drum is transferred to a recording material such as a recording sheet or a plastic sheet, and the toner image is further applied by applying heat or pressure to the toner image transferred onto the recording material. Image recording is performed by fixing on a recording material.

  Such an image forming apparatus generally requires toner replenishment and maintenance of various process means. In order to facilitate the toner replenishment and maintenance, the electrophotographic photosensitive drum, charging means, developing means, cleaning means, etc. are grouped in a frame and made into a cartridge, and a process cartridge which can be detached from the image forming apparatus main body is made. It has been put to practical use.

  According to this process cartridge system, since the maintenance of the apparatus can be performed by the user himself / herself, the operability can be remarkably improved, and an image forming apparatus excellent in usability can be provided. Therefore, this process cartridge system is widely used in image forming apparatuses.

  In the case of shipping the process cartridge described above, it may be transported, shipped, and sold in a state where the process cartridge is mounted on the main body of the image forming apparatus in consideration of the reduction of physical distribution costs and the convenience at the time of use for the user. To be done. At this time, there is known a separating member for separating components which abut on the surface of the electrophotographic photosensitive drum at the time of transportation (see Patent Document 1 and FIG. 1). Furthermore, in the separating member described in Patent Document 1, a locus for assembling the separating member and a locus for the separation releasing operation are provided on substantially the same plane (see Patent Document 1 and FIG. 15). This achieves space saving by coexistence of the space used for assembly and the space used for clearance release.

JP, 2016-110134, A

  In the configuration as described above, it is necessary to eliminate, as much as possible, an obstacle on a plane on which the locus of assembling the spacing member and the locus of the spacing release operation exist. However, when the obstacle is eliminated, there is no obstacle for restricting the movement of the separating member when the electrophotographic photosensitive drum and the parts in contact with the surface of the electrophotographic photosensitive drum become excessively separated and the holding force of the separating member decreases. Could easily come off.

  An object of the present invention is to provide a process cartridge in which the separation member is prevented from coming off at the time of excessive separation without inhibiting the assembling operation and the separation releasing operation of the separation member.

In order to achieve the above object, the process cartridge according to the present invention is
A process cartridge removable from an electrophotographic image forming apparatus for transferring a toner image to a recording medium by a transfer roller to form an image, comprising: an electrophotographic photosensitive drum; and a cleaning unit comprising the electrophotographic photosensitive drum. A regulating portion provided in the cleaning unit, a developing roller for developing toner on the electrophotographic photosensitive drum, and a development separating position including the developing roller and the developing roller separated from the electrophotographic photosensitive drum A developing unit movable to a developing position where the developing roller can develop, a separation member attached to the process cartridge, a development separation part provided on the separation member, a transfer separation part, and a regulated part Wherein the spacing member is movable between a first position and a second position. Ri, and the locus assembling the spacer member is a trajectory when assembled, the moving track the spacer member is moved to said second position from said first position is located substantially on the same plane,
When the separation member is in the first position, the development separation portion abuts on both a part of the cleaning unit and a part of the development unit, and holds the development unit in the development separation position. And the restricted portion restricts the movement of the separating member in the releasing direction by engaging with the restricting portion when the separating member moves in the separating direction different from the assembling locus and the movement locus. And when the transfer roller is mounted on the electrophotographic image forming apparatus, the transfer separation unit holds the transfer roller at a transfer separation position separated from the electrophotographic photosensitive drum different from the transfer position to which the transfer can be transferred; When the separation member is in the second position, the development separation portion releases the holding of the development unit to move the development unit from the development separation position to the development position. Ri, the transfer separation portion, by releasing the holding of the transfer roller, the transfer roller is characterized by comprising movable in the transfer position.

  According to the process cartridge of the present invention, the assembly operation and separation of the separation member can be performed by providing the restricting portion and the regulated portion which are engaged when the separation member performs the movement unrelated to the assembling operation and the separation releasing operation. It is possible to prevent the detachment of the spacing member at the time of excessive separation without inhibiting the release operation.

It is the side view which looked at the state where the separation member concerning a 1st embodiment to which the present invention is applicable was attached to a process cartridge, and was attached to the main part of a device from the drive side of a main part of a device. FIG. 1 is a cross-sectional view of an image forming apparatus main body and a process cartridge of an electrophotographic image forming apparatus according to a first embodiment to which the present invention is applicable. FIG. 1 is a cross-sectional view of a process cartridge according to a first embodiment to which the present invention is applicable. FIG. 5 is a cross-sectional view of the inside of the cleaning container of the process cartridge according to the first embodiment to which the present invention is applicable. FIG. 1 is a perspective view of an image forming apparatus main body in a state in which an open / close door of an electrophotographic image forming apparatus according to a first embodiment to which the present invention can be applied is opened. FIG. 2 is a perspective view of the image forming apparatus main body in a state in which the open / close door of the electrophotographic image forming apparatus according to the first embodiment to which the invention can be applied is opened and the tray is pulled out. The electrophotographic image forming apparatus according to the first embodiment to which the present invention can be applied is a perspective view of an image forming apparatus main body and a process cartridge when the process cartridge is attached to and detached from the tray with the door opened and the tray pulled out. It is. FIG. 2 is a perspective view of a process cartridge and a drive-side positioning portion of the image forming apparatus main body in a state where the process cartridge is mounted on the electrophotographic image forming apparatus main body according to the first embodiment to which the present invention is applicable. FIG. 2 is a perspective view of a non-driving side positioning portion of the process cartridge and the image forming apparatus main body in a state where the process cartridge is mounted on the electrophotographic image forming apparatus main body according to the first embodiment to which the present invention is applicable. It is an exploded view of a process cartridge concerning a 1st embodiment to which the present invention is applicable. It is an exploded view of a process cartridge concerning a 1st embodiment to which the present invention is applicable. It is an exploded view of a process cartridge concerning a 1st embodiment to which the present invention is applicable. It is an exploded view of a process cartridge concerning a 1st embodiment to which the present invention is applicable. It is the perspective view which showed the separation member which concerns on 1st Embodiment which can apply this invention. FIG. 6 is a perspective view illustrating the mounting of the spacing member according to the first embodiment to which the present invention is applicable to the process cartridge. It is a schematic side view seen from the drive side explaining the state where the separation member concerning the 1st embodiment which can apply the present invention was attached. It is the schematic side view seen from the drive side explaining the process in which the separation member which concerns on 1st Embodiment which can apply this invention moves to a 2nd position from a 1st position. FIG. 7 is a schematic side view as seen from the drive side when the process cartridge to which the separating member according to the first embodiment to which the present invention can be applied is attached is in the over-spacing state. FIG. 19 is a detail view of the periphery of a developing separation portion in FIG. 18;

First Embodiment
Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

  The direction of the rotational axis of the electrophotographic photosensitive drum is taken as the longitudinal direction. Further, in the longitudinal direction, the side to which the electrophotographic photosensitive drum receives the driving force from the image forming apparatus main body is set as the driving side, and the opposite side is set as the non-driving side.

  The entire configuration and the image forming process will be described with reference to FIGS. 2 and 3. FIG. 2 is a cross-sectional view of an image forming apparatus main body (hereinafter referred to as an apparatus main body A) and a process cartridge (hereinafter referred to as a cartridge B) of an electrophotographic image forming apparatus according to an embodiment of the present invention. . FIG. 3 is a cross-sectional view of the cartridge B. Here, the apparatus main body A is a portion of the electrophotographic image forming apparatus from which the cartridge B is removed.

<Overall Configuration of Electrophotographic Image Forming Apparatus>
The electrophotographic image forming apparatus shown in FIG. 2 is a laser beam printer using an electrophotographic technology in which the cartridge B is detachably attached to the apparatus main body A. When the cartridge B is mounted to the apparatus main body A, the exposure device 3 (laser scanner unit) for forming a latent image on the electrophotographic photosensitive drum 62 of the cartridge B is disposed. Further, below the cartridge B, a sheet tray 4 storing a recording medium (hereinafter, referred to as a sheet material P) to be an image forming object is disposed.

  Further, in the apparatus main body A, along the conveying direction D of the sheet material P, the pickup roller 5a, the pair of feeding rollers 5b, the pair of conveying rollers 5c, the transfer guide 6, the transfer roller 7, the conveyance guide 8, the fixing device 9, The discharge roller pair 10, the discharge tray 11 and the like are sequentially arranged. The fixing device 9 includes a heating roller 9a and a pressure roller 9b.

<Image formation process>
Next, an outline of the image forming process will be described.

  Based on the print start signal, the electrophotographic photosensitive drum (hereinafter referred to as the drum 62) is rotationally driven in the direction of arrow R at a predetermined circumferential speed (process speed). The charging roller 66 to which the bias voltage is applied is in contact with the outer peripheral surface of the drum 62, and uniformly charges the outer peripheral surface of the drum 62 uniformly.

  The exposure device 3 outputs a laser beam L according to the image information. The laser beam L passes through a laser opening 71 h provided in the cleaning frame 71 of the cartridge B, and scans and exposes the outer peripheral surface of the drum 62. Thereby, an electrostatic latent image corresponding to the image information is formed on the outer peripheral surface of the drum 62.

On the other hand, as shown in FIG. 3, in the developing unit 20 as the developing device, the toner T in the toner chamber 29 is stirred and transported by the rotation of the first transport member 43, the second transport member 44 and the third transport member 50. And sent to the toner supply chamber 28. The toner T is carried on the surface of the developing roller 32 by the magnetic force of the magnet roller 34 (fixed magnet). The toner T is frictionally charged by the developing blade 42 and the layer thickness on the circumferential surface of the developing roller 32 is regulated. The toner T is developed on the drum 62 according to the electrostatic latent image and visualized as a toner image.

  Further, as shown in FIG. 2, the sheet material P stored in the lower part of the apparatus main body A is a sheet tray by the pickup roller 5a, the pair of feeding rollers 5b, and the pair of conveying rollers 5c. It is sent out from 4. Then, the sheet material P is conveyed to the transfer position between the drum 62 and the transfer roller 7 via the transfer guide 6. At this transfer position, the toner image is sequentially transferred from the drum 62 to the sheet material P.

  The sheet material P on which the toner image has been transferred is separated from the drum 62 and conveyed to the fixing device 9 along the conveyance guide 8. Then, the sheet material P passes through the nip portion between the heating roller 9 a and the pressure roller 9 b which constitute the fixing device 9. The pressure and heat fixing process is performed at the nip portion, and the toner image is fixed to the sheet material P. The sheet material P subjected to the fixing process of the toner image is conveyed to the discharge roller pair 10 and discharged to the discharge tray 11.

  On the other hand, as shown in FIG. 3, the drum 62 after transfer has the residual toner on the outer peripheral surface removed by the cleaning blade 77, and is used again in the image forming process. The toner removed from the drum 62 is stored in the waste toner chamber 71 b of the cleaning unit 60.

  In the above, the charging roller 66, the developing roller 32, the transfer roller 7, and the cleaning blade 77 are process means for acting on the drum 62.

<Cartridge removal>
Next, mounting and demounting of the cartridge B with respect to the apparatus main body A will be described with reference to FIGS. 5 and 6. FIG. 5 is a perspective view of the apparatus main body A in which the open / close door 13 is opened in order to attach and detach the cartridge B. As shown in FIG. FIG. 6 is a perspective view of the apparatus main body A and the cartridge B in a state in which the open / close door 13 is opened and the tray 18 is pulled out in order to attach and detach the cartridge B. FIG. 7 is a perspective view of the apparatus main body A and the cartridge B when the cartridge B is attached and detached in a state in which the open / close door 13 is opened and the tray 18 is pulled out.

  The cartridge B is attachable to and detachable from the tray 18 along the attaching and detaching direction E. An opening / closing door 13 is rotatably attached to the apparatus main body A, and when the opening / closing door 13 is opened, a cartridge insertion port 17 is provided. In the cartridge insertion slot 17, a tray 18 for mounting the cartridge B to the apparatus main body A is provided. When the tray 18 is pulled out to a predetermined position, the cartridge B can be attached and detached. The cartridge B is mounted in the apparatus main body A along a guide rail (not shown) in the direction of arrow C in the drawing while being mounted on the tray 18.

  Further, a first drive shaft 14 and a second drive shaft 19 for transmitting a drive to the first coupling 70 and the second coupling 21 (FIG. 8) provided in the cartridge B are provided. The first drive shaft 14 and the second drive shaft 19 are driven by a motor (not shown) of the apparatus main body A. Thus, the drum 62 connected to the first coupling 70 receives the driving force from the apparatus main body A and rotates. Further, the drive is transmitted from the second coupling 21 and the developing roller 32 is rotated. Further, the charging roller 66 and the developing roller 32 are supplied with power from a power supply unit (not shown) of the apparatus main body A.

<Cartridge support>
As shown in FIG. 5, the apparatus main body A is provided with a driving side plate 15 and a non-driving side plate 16 for supporting the cartridge B. As shown in FIGS. 8 and 9, the drive side plate 15 is provided with the drive side first support portion 15a, the drive side second support portion 15b and the rotation support portion 15c of the cartridge B, and the non-drive side plate 16 is not driven. A side first support portion 16a, a non-drive side second support portion 16b, and a rotation support portion 16c are provided.

  On the other hand, as supported portions of the cartridge B, supported portions 73b of the drum bearing 73, supported portions 73d, driving side bosses 71a of the cleaning frame 71, non-driving side projections 71f and non-driving side bosses 71g are provided. ing. The supported portion 73b is supported by the drive-side first support portion 15a, and the supported portion 73d is supported by the drive-side second support portion 15b, and the drive-side boss 71a is supported by the rotation support portion 15c. Further, the non-drive side protrusion 71f is supported by the non-drive side first support portion 16a and the non-drive side second support portion 16b, and the non-drive side boss 71g is supported by the rotation support portion 16c, whereby the cartridge B is It is positioned in the device body A.

<Configuration of Entire Cartridge>
Next, the entire configuration of the cartridge B will be described with reference to FIGS. 3, 4, 10, 11, 12, and 13. FIG. 3 is a cross-sectional view of the cartridge B, and FIGS. 10, 11, 12 and 13 are perspective views for explaining the configuration of the cartridge B. FIG. FIGS. 11 and 13 are partially enlarged views in which the positions in the dotted line in FIGS. 10 and 12 are enlarged at different angles. In the present embodiment, the screws for connecting the components are omitted and described.

  The cartridge B has a cleaning unit 60 and a developing unit 20. Generally, a process cartridge is an electrophotographic image forming apparatus in which an electrophotographic photosensitive member and at least one of a charging unit, a developing unit, and a cleaning unit as a process unit acting on the electrophotographic photosensitive member are integrally formed into a cartridge. It is made detachable with respect to the main body of. In the present invention, the process cartridge at least has the cleaning unit 60 according to the present invention.

  As shown in FIG. 3, the cleaning unit 60 includes a drum 62, a charging roller 66, a cleaning member 77, a cleaning frame 71 for supporting them, and a cover member 72 fixed to the cleaning frame 71 by welding or the like. Have. In the cleaning unit 60, the charging roller 66 and the cleaning member 77 are disposed in contact with the outer peripheral surface of the drum 62, respectively.

  The cleaning member 77 has a rubber blade 77a, which is a blade-like elastic member formed of rubber as an elastic material, and a support member 77b for supporting the rubber blade. The rubber blade 77 a is in contact with the drum 62 in the counter direction with respect to the rotational direction of the drum 62. That is, the rubber blade 77 a is in contact with the drum 62 such that the tip end faces the upstream side in the rotational direction of the drum 62.

  FIG. 4 is a cross-sectional view of the cleaning frame 71. As shown in FIGS. 3 and 4, the waste toner removed from the surface of the drum 62 by the cleaning member 77 is conveyed by the first screw 86, the second screw 87, and the third screw 88 as waste toner conveying members. The toner is stored in a waste toner chamber 71 b formed by the cleaning frame 71 and the lid member 72.

  The first screw 86 is rotated by a drive (not shown) transmitted from the coupling 21 shown in FIG. The second screw 87 receives a driving force from the first screw 86, and the third screw 88 receives a driving force from the second screw 87, and rotates. The first screw 86 is disposed near the drum 62, the second screw 87 is disposed at the longitudinal end of the cleaning frame 71, and the third screw 88 is disposed in the waste toner chamber 71b. Here, the rotational axes of the first screw 86 and the third screw 88 are parallel to the rotational axis of the drum 62, and the rotational axis of the second screw 87 is orthogonal to the rotational axis of the drum 62.

  Further, as shown in FIG. 3, a squeeze sheet 65 for preventing the waste toner from leaking from the cleaning frame 71 is provided at the edge of the cleaning frame 71 so as to abut on the drum 62.

  The drum 62 is rotationally driven in the direction of arrow R in the figure in accordance with the image forming operation by receiving a driving force from a main body driving motor (not shown) which is a driving source.

  The charging roller 66 is rotatably attached to the cleaning unit 60 via a charging roller bearing 67 at both end portions of the cleaning frame 71 in the longitudinal direction (substantially parallel to the rotational axis direction of the drum 62). The charging roller 66 is in pressure contact with the drum 62 by the charging roller bearing 67 being pressed toward the drum 62 by the biasing member 68. The charging roller 66 is driven to rotate by the rotation of the drum 62.

  As shown in FIG. 3, the developing unit 20 has a developing roller 32, a developing container 23 supporting the developing roller 32, a developing blade 42 and the like. A magnet roller 34 is provided in the developing roller 32. Further, in the developing unit 20, a developing blade 42 for regulating the toner layer on the developing roller 32 is disposed. As shown in FIGS. 10 and 12, the spacing roller 38 is attached to both ends of the developing roller 32 on the developing roller 32, and the spacing roller 38 and the drum 62 are in contact with each other. It is held with 62 and a slight gap.

  Further, as shown in FIG. 3, a blowout preventing sheet 33 for preventing the toner from leaking from the developing unit 20 is provided at the edge of the bottom member 22 so as to abut on the developing roller 32. Further, in the toner chamber 29 formed by the developing container 23 and the bottom member 22, a first conveyance member 43, a second conveyance member 44, and a third conveyance member 50 are provided. The first conveying member 43, the second conveying member 44, and the third conveying member 50 agitate the toner stored in the toner chamber 29 and convey the toner to the toner supply chamber 28.

  As shown in FIGS. 10 and 12, the cartridge B is configured by combining the cleaning unit 60 and the developing unit 20.

  The cleaning unit 60 is provided with a cleaning frame 71, a cover member 72, a drum 62, a drum bearing 73 for rotatably supporting the drum 62, and a drum shaft 78. As shown in FIG. 13, on the drive side, the drum 62 is rotatably supported by the hole 73 a of the drum bearing 73 with the end member 63 provided on the drive side (hereinafter, the drive-side drum flange 63). . On the other hand, as shown in FIG. 11, on the non-driving side, the drum shaft 78 press-fitted into the hole 71c provided in the cleaning frame 71 can rotate the hole (not shown) of the non-driving side drum flange 64. Support the

  On the other hand, as shown in FIGS. 3, 10 and 12, the developing unit 20 comprises a bottom member 22, a developing container 23, a driving side developing side member 26, a developing blade 42, a developing roller 32 and the like. The developing roller 32 is rotatably attached to the developing container 23 by bearings 27 and 37 provided at both ends.

  Then, as shown in FIGS. 11 and 13, the cartridge B is configured by rotatably coupling the cleaning unit 60 and the developing unit 20 with the coupling pin 69. Specifically, at both ends in the longitudinal direction of the developing unit 20, a developing first support hole 23a and a developing second support hole 23b are provided in the developing container 23. Further, at both ends in the longitudinal direction of the cleaning unit 60, a first suspension hole 71i and a second suspension hole 71j are provided in the cleaning frame 71. The cleaning unit 60 and the developing unit 20 rotate relative to each other by fitting the first suspension hole 71i, the coupling pin 69 press-fitted and fixed to the second suspension hole 71j, and the development first support hole 23a and the development second support hole 23b. It is linked in a movable manner.

  The first hole 46Ra of the drive side biasing member 46R is hooked on the boss 73c of the drum bearing 73, and the second hole 46Rb is hooked on the boss 26a of the drive side developing side member 26. Further, the first hole 46Fa of the non-driving side biasing member 46F is hooked on the boss 71k of the cleaning frame 71, and the second hole 46Fb is hooked on the boss 37a of the bearing member 37.

  In the present embodiment, the drive side biasing member 46R and the non-drive side biasing member 46F are formed by tension springs, and the developing unit 20 is biased to the cleaning unit 60 by the biasing force of the springs. 32 is configured to be pressed firmly in the direction of the drum 62. The developing roller 32 is held at a predetermined distance from the drum 62 by the spacing members 38 attached to both ends of the developing roller 32.

<Configuration of Spacing Member>
Next, the separating member 48 will be described in detail with reference to FIGS. 14 and 15. FIG. 14 is a perspective view showing the spacing member 48. As shown in FIG. FIG. 15 is a perspective view illustrating the attachment of the spacer 48 to the cartridge B. As shown in FIG.

  As shown in FIG. 14, the separation member 48 has a development separation part 48a, a transfer separation part 48b, and a guide part 48c. Then, an arc-shaped elastically deformable portion 48d is provided outside the guide portion 48c. Further, a groove 48 h is formed in a space sandwiched between the guide portion 48 c and the elastic deformation portion 48 d. A portion of the elastically deformable portion 48d has a convex portion 48e having a shape projecting into the groove 48h. An engaging portion 48 f is engaged with an engaged portion 63 a provided on a driving side drum flange 63 of the drum 62 described later.

  As shown in FIG. 15, the cleaning unit 60 has a mounting portion 60a and a guided portion 60b in an arc shape centered on the axis of the drum 62, and the mounting portion 60a is formed by the guide portion 48c of the separating member 48 and the elastic deformation portion 48d. The separating member 48 is attached to the cleaning unit 60 by inserting the groove portion 48 h.

  Next, the separating member 48 is attached to the process cartridge B by inserting the separating portion 48 a between the contact portion 60 d of the cleaning unit 60 and the contact portion 20 a of the developing unit 20 (arrow U). Although the function will be described later, the drum 62 has a drive-side drum flange 63 as an end member at an axial end, and has an engaged portion 63a at a part thereof.

  FIG. 1 is a side view of a state where the separating member 48 is attached to the cartridge B and attached to the apparatus main body A from the drive side of the apparatus main body A. FIG. The separating member 48 is movable as the guide portion 48c is rotatably supported about the axis of the drum 62 along the guide portion 60b. The spacing member 48 which moves in the present description has a first position and a second position.

  The first position of the separating member 48 is a position at which the developing unit 20 is held such that the separating member 48 positions the developing roller 32 away from the drum 62, and the position at which the transfer roller 7 is separated from the drum 62. It is a position which holds transfer roller 7 so that it may become.

  The second position of the separating member 48 is a position at which the separating member 48 releases the holding of the developing unit 20, the developing roller 32 is at the image forming position, and the holding of the transfer roller 7 is released. At a position where the transfer roller 7 is in pressure contact with the drum 62.

  The separation and release of the drum 62 and the developing roller 32 and the separation and release of the drum 62 and the transfer roller 7 will be described with reference to FIG.

Separation of the drum and the developing roller
First, separation and release of the drum 62 and the developing roller 32 will be described in detail.

[Development roller separation state]
FIG. 1A shows a state in which the spacing member 48 is in the first position. The developing separating portion 48 a of the separating member 48 is inserted between the contact portion 60 d of the cleaning unit 60 and the contact portion 20 a of the developing unit 20 and is in contact with both.

  The developing unit 20 rotates about the first suspension hole 71i and the second suspension hole 71j (not shown) provided in the cleaning frame 71 of the cleaning unit 60 described above by the thickness of the inserted development separating portion 48a. It is rotated and held in the arrow V1 direction. The distance between the surface of the developing roller 32 and the surface of the drum 62 in this state is l1, and this distance l1 is larger than the distance l2 between the surface of the developing roller 32 and the surface of the drum 62 at the time of image formation described later.

  That is, the spacing member 38 and the drum 62 are separated or in contact with a pressure lower than the pressure required for image formation. By inserting the developing separation portion 48a, the distance between the drum 62 and the developing roller 32 is larger than the distance required for image formation (developing roller 32 separation).

[Development roller separation release]
FIG. 1B shows the state where the spacer member 48 is in the second position. As the separation member 48 moves from the first position to the second position, the development separation portion 48a moves to a position separated from the contact portion 20a. The first suspension hole 71i and the second suspension hole 71j (not shown) provided in the cleaning frame 71 of the cleaning unit 60 described above are eliminated because the contact between the development separating portion 48a and the abutting portion 20a is eliminated. Can be turned in the direction of the drum 62 (the direction of the arrow V2) about the turning center.

  By the rotation of the developing unit 20, the developing roller 32 is pressed in the direction of the drum 62 by the urging force of the driving side urging member 46R and the non-driving side urging member 46F, and the distance attached to both ends of the developing roller 32 The holding member 38 abuts on the drum 62. The surface of the developing roller 32 and the surface of the drum 62 remain at a predetermined distance (12) (developing roller 32 separation release).

<Separation and release of the drum and transfer roller>
Next, separation and release of the drum 62 and the transfer roller 7 will be described.

[Separation of transfer roller]
As described above, FIG. 1A shows the state in which the spacing member 48 is in the first position. The transfer roller 7 has an elastic roller portion 7b rotatable around a core 7a. Then, the elastic roller portion 7b is brought into pressure contact with the drum 62 by urging it in the direction of the drum 62 by a spring (not shown) via a bearing (not shown) rotatably supporting the core 7a. There is. The cored bar 7a is movable in the direction of arrow S within the biasing range of a spring (not shown).

  When the cartridge B in which the separating member 48 is in the first position is mounted on the apparatus main body A, the transfer separating portion 48 b and the core metal 7 a at both ends of the transfer roller 7 are in contact with each other.

  As the process cartridge B is mounted in the mounting direction (arrow C), the transfer separation portion 48b pushes the cored bar 7a in the '-' direction of the arrow S. As a result, the transfer roller 7 moves away from the drum 62.

  The restricting portion 48b holds the elastic roller portion 7b of the transfer roller 7 in a state of being separated from the surface of the drum 62 or in contact with a lower pressure than in pressure contact during image formation (transfer roller 7 separation).

[Release of separation of transfer roller]
As described above, FIG. 1 (b) shows the state in which the spacing member 48 is in the second position. As the spacer member 48 moves from the first position to the second position, the transfer spacer 48b moves to a position separated from the cored bar 7a. Since the contact between the transfer / separation portion 48b and the cored bar 7a is eliminated, the transfer roller 7 can move in the '+' direction of the arrow S. Then, the elastic roller portion 7b is in pressure contact with the drum 62, and the transfer roller 7 remains at the image forming position (transfer roller 7 separation release).

  When the separating member 48 having the contents described above is in the first position, one part simultaneously separates the developing roller 32 from the drum 62 and separates the transfer roller 7 from the drum 62 simultaneously. Is possible.

  When transporting the process cartridge B mounted on the apparatus main body A, the separating member 48 is in the first position. In this state, since the developing roller 32 and the transfer roller 7 are separated from the drum 62, the surface of the drum 62, the surface of the developing roller 32, the surface of the transfer roller 7 when impact or vibration due to physical distribution is applied in this state. It is possible to prevent the surface from being scratched.

  Further, the separating member 48 is in contact with and fixed at a plurality of positions (the abutting portion 60d of the cleaning unit 60 and the abutting portion 20a of the developing unit 20 are in contact with each other and the transfer roller 7). Hard to come off against vibration or vibration.

<Movement of Spacing Member from First Position to Second Position>
Next, the movement of the spacing member 48 from the first position to the second position will be described in detail. The state in which the spacing member 48 moves from the first position to the second position will be described using FIGS. 16 and 17. FIG. 16 is a schematic side view seen from the drive side of the apparatus main body A, illustrating the state in which the separating member 48 is attached. FIG. 17 is a schematic side view seen from the drive side of the apparatus main body A, illustrating the process of moving the spacer member 48 from the first position to the second position.

  The configuration of the mechanism for moving the spacing member 48 and the spacing member 48 will be described with reference to FIG.

  As described above, the separating member 48 is attached by inserting the groove portion 48h formed by the space between the guide portion 48c and the elastic deformation portion 48d into the attaching portion 60a. The separating member 48 can be rotationally moved about the axis of the drum 62 by the guide portion 48c being guided by the guided portion 60b. The guided portion 60b has an arc shape with a range of the angle α around the axis of the drum 62, and has an end point 60c on the downstream side of the rotation direction R of the drum 62. The separating member 48 is provided with a locking portion 48g at the tip of the elastically deformable portion 48d to prevent rotation in the direction opposite to the rotation direction R of the drum 62.

  Further, assuming that the width of the groove 48h is W1, the width of the groove 48h at the portion where the protrusion 48e is present is W2, and the width of the mounting portion 60a is W3, the relationship is W3 ≒ W1> W2. Further, when the distance of the engaged portion 63a provided on the drum flange 63 from the drum 62 axial center is r1, and the distance of the engaging portion 48f of the separating member 48 from the drum 62 axial center is r2, the relationship is r1> r2. It has become.

  As shown in FIG. 17A, when the drum 62 rotates in the R direction, the engaged portion 63a abuts on the engaging portion 48f. Then, when the rotation of the drum 62 continues, since the guide portion 48c of the separating member 48 is guided by the guided portion 60b as described above, the separating member 48 rotates and moves in the rotational direction R about the axis of the drum 62. Get started.

  As shown in FIG. 17B, when the movement proceeds further, the position where the projection 48e in the groove 48h comes in contact with the mounting portion 60a is reached.

  As described in FIG. 16, since the widths of both have the relationship of W3> W2, when the convex portion 48 e comes in contact with the mounting portion 60 a and tries to get over, the elastic deformation portion 48 d starts elastic deformation and the drum 62 axis It is deformed to the radius outside (arrow Q side) centering on. In addition, when the elastically deformable portion 48d is elastically deformed, the guide portion 48c reaches the end point 60c of the guided portion 60b.

  As shown in FIG. 17C, the protrusion 48e passes over the attachment portion 60a, thereby preventing the separation member 48 from rotating in the reverse direction (in the direction opposite to the direction of the arrow R) and preventing the protrusion 48e from guiding. By abutting on 60b, the posture of the separating member 48 is regulated and held.

  The position where the convex portion 48e is regulated and held is a distance from the axial center of the drum 62 to the convex portion 48e as r4, and from the axial center of the drum 62 when the separating member 48 described in FIG. The relationship is r4> r3 when the distance to the convex portion 48e is r3. That is, the convex portion 48e is held at a position spaced outward (in the direction of the arrow Q) in the radial direction of the central axis of the drum 62.

  The guide portion 48c is not guided by the guided portion 60b, and moves toward the radially outer side (arrow Q) centering on the axis of the drum 62 to return to the original shape with the convex portion 48e as a fixed point when returning to the original shape. It will be done. At the same time, the engaging portion 48f also moves in the arrow Q direction.

  The distance between the engaging portion 48f and the center of the axis of the drum 62 is r5, and the relationship between the center of the axis of the drum 62 and the engaged portion 62b is r1 <r5 as described above with reference to FIG. The engagement of the joint 62b is released. The rotation of the drum 62 is not transmitted to the spacing member 48, and the spacing member 48 is in the second position.

  Furthermore, in the present embodiment, the arrow U (FIG. 15), which is the mounting locus of the separating member 48, and the arrow R (FIG. 16), the moving locus from the first position to the second position of the separating member 48, are substantially identical. It is provided on a plane. This achieves space saving by coexistence of the space used for assembly and the space used for clearance release.

  Next, a configuration will be described in which the separating member is prevented from coming off when the separating member 48 is in the first position and further excessive separation occurs.

<Description of over distanced condition>
First, the excessive separation state will be described with reference to FIG. FIG. 18 is a schematic side view of the cartridge B in which excessive separation has occurred from the drive side. Here, in order to indicate that the transfer roller 7 is separated from the cartridge B, the transfer roller 7 is illustrated by a two-dot chain line.

  The cartridge B with the separating member 48 mounted at the first position is passed to the user's hand in the state mounted on the apparatus main body A, but before the separating member 48 is moved from the first position to the second position. The user may take out the cartridge B from the apparatus main body A.

  Since the transfer roller 7 is disposed in the apparatus main body A, when the cartridge B is removed from the apparatus main body A, the transfer roller 7 is separated from the cartridge B. As a result, the contact between the transfer / separation portion 48b of the separation member 48 and the cored bar 7a of the transfer roller 7 in the first position is released.

  Further, after the cartridge B is removed from the apparatus main body A, depending on the user's operation, a force may further act on the cleaning unit 60 to further rotate the developing unit 20 in the arrow V1 direction. At this time, the developing separating portion 48a of the separating member 48 in the first position and the abutting portion 20a of the developing unit 20 are separated to a position where they can not abut.

  As described above, the excessively separated state is a state in which the developing unit 20 and the transfer roller 7 are further separated from the state separated by the separating member 48.

<Configuration to prevent separation member from coming off>
As described above, the separating member 48 is in contact with and fixed at a plurality of positions (the contact portion 60d of the cleaning unit 60, the contact portion 20a of the developing unit 20, the core metal 7a of the transfer roller 7). It is hard to come off against

  However, when excessive separation occurs, these holding powers are lost, and the separation member 48 tends to be detached in the direction of the arrow S by pivoting about the mounting portion 60a. The direction of the arrow S points in a direction different from the arrow U which is an assembly trajectory of the spacing member 48 and the arrow R which is a movement trajectory from the first position to the second position of the spacing member 48.

  A specific direction will be described using FIG. FIG. 19 is a detailed view of the periphery of the development separation portion 48 a of the cartridge B (FIG. 18) in which excessive separation has occurred.

  The arrow U which is an assembly | attachment locus | trajectory of the separation member 48 turns to substantially horizontal direction in the end point vicinity of the arrow U which is just before completion of an assembly | attachment. Further, the arrow R, which is a movement locus from the first position of the spacing member 48 to the second position, is substantially horizontal in the vicinity of the start point of the arrow R at the start of movement. On the other hand, the arrow S which is the removal direction of the spacing member 48 faces obliquely downward in the vicinity of the start point of the arrow S which is the beginning of the removal. As described above, the out direction arrow S points in a direction different from the assembly path arrow U and the movement path arrow R, particularly when the spacing member 48 is close to the first position.

  In the present embodiment, as shown in FIGS. 18 and 19, the cleaning unit 60 is provided with the restricting portion 60e, and the separation member 48 is provided with the restricted portion 48i. When the separating member 48 moves in the direction of the arrow S in order to release it, the developing separating portion 48a pivots downward in the diagonal direction, so that the regulating portion 60e and the regulated portion 48i are engaged, the arrow S of the separating member 48 Movement in the direction is restricted.

  However, when the separating member 48 moves in the direction of the arrow U which is the mounting locus of the separating member 48 and the arrow R which is the moving locus from the first position of the separating member 48 to the second position, the developing separating portion 48a In this case, the restricting portion 60e and the restricted portion 48i do not engage with each other, and the movement of the separating member 48 is not inhibited.

  As a result, it is possible to prevent the separating member from being detached even at the time of excessive separation, without increasing the load of the assembling operation and the separation releasing operation.

  As described above, in the electrophotographic image forming apparatus according to the present invention, the movement of the separation member 48 in the direction in which the separation member 48 tends to come off during excessive separation is regulated, and the assembly direction of the separation member 48 and the separation release operation direction The control part 60e and the controlled part 48i which do not inhibit movement of are provided. As a result, it is possible to prevent the separating member from being detached even at the time of excessive separation, without increasing the load of the assembling operation and the separation releasing operation.

  The functions, materials, shapes and relative arrangements of components described in the present embodiment are not intended to limit the scope of the present invention to them unless otherwise specifically described.

3 Exposure device (laser scanner unit), 4 sheet tray,
5a pickup roller, 5b feed roller pair, 5c transport roller pair,
6 transfer guide, 7 transfer roller, 8 conveyance guide, 9 fixing device,
9a heating roller, 9b pressure roller, 10 discharge roller pair,
11 discharge tray, 13 opening / closing door, 14 ... first drive shaft, 15 drive side plate,
15a drive-side first support, 15b drive-side second support, 15c rotational support,
16 non-drive side plate, 16a non-drive side first support, 16b non-drive side second support,
16c rotary support, 17 cartridge insertion slot, 18 tray,
19 second drive shaft, 20 developing unit, 21 second coupling,
22 bottom member, 23 developer container, 23a development first support hole, 23b development second support hole,
26 drive side developing side member, 26a boss, 27 bearing member,
28 toner supply chamber, 29 toner chamber, 32 developing roller (developer carrier),
33 blowout prevention sheet, 34 magnet roller, 37 bearing member,
37a boss, 38 spacing member, 42 developing blade (developer regulating member),
43 first transport member, 44 second transport member, 46R drive side biasing member,
46Ra first hole, 46Rb second hole, 46F non-drive side biasing member,
46Fa first hole, 46Fb second hole, 48 separating members, 48a developing separating portion,
48b transfer separation portion, 48c guide portion, 48d elastic deformation portion, 48e convex portion,
48f engaging part, 48g locking part, 48h groove part, 48i controlled part,
50 third conveyance member, 60 cleaning unit, 60a attachment portion,
60b guided portion, 60c end point, 60d abutting portion, 60e restricting portion,
62 drum (electrophotographic photosensitive drum), 63 drive side drum flange,
64 non-driving side drum flange, 65 square sheet, 66 charging roller,
67 charging roller bearing, 68 biasing member, 69 coupling pin, 70 first coupling,
71 cleaning frame, 71a drive side boss, 71b waste toner chamber, 71c hole,
71f non-drive side projection, 71g non-drive side boss, 71h laser aperture,
71i first suspension hole, 71j second suspension hole, 71k boss, 72 lid member,
73 drum bearing, 73a hole, 73b supported portion, 73c boss,
73d Supported part, 77 cleaning blade, 77a rubber blade,
77b support member, 78 drum shaft, 86 first screw, 87 second screw,
88 Third screw, A Image forming apparatus main body (apparatus main body),
B process cartridge (cartridge), C insertion direction, D transport direction,
E Mounting direction, L laser light, T toner (developer),
U assembly direction (assembly trajectory), P sheet material (recording medium),
R rotation direction (movement locus), S deviation direction, V1, V2 rotation direction,
l1, l2 interval,

Claims (3)

A process cartridge detachably mountable to an electrophotographic image forming apparatus for transferring a toner image onto a recording medium by a transfer roller to form an image,
An electrophotographic photosensitive drum,
A cleaning unit having the electrophotographic photosensitive drum;
A regulation unit provided in the cleaning unit;
A developing roller for developing toner on the electrophotographic photosensitive drum;
Including the developing roller,
A development separation position in which the development roller is separated from the electrophotographic photosensitive drum;
A developing unit movable to a developing position where the developing roller is capable of developing;
A separation member attached to the process cartridge;
A development separating portion, a transfer separating portion, and a regulated portion provided on the separating member;
Process cartridge equipped with
The spacing member is movable to a first position and a second position;
An assembly locus which is a locus when the separating member is assembled, and a movement locus in which the separating member moves from the first position to the second position,
On the same plane,
When the spacing member is in the first position,
The development separating portion is
Contacting both a part of the cleaning unit and a part of the developing unit, and holding the developing unit in the developing separation position,
And the controlled portion is
When the separating member moves in a direction different from the assembling trajectory and the moving trajectory, engagement with the restricting portion restricts the movement of the separating member in the releasing direction.
Further, when mounted on the electrophotographic image forming apparatus,
The transfer separation portion is
The transfer roller is held at a transfer separation position apart from the electrophotographic photosensitive drum different from the transfer position where transfer is possible,
When the spacing member is in the second position,
The development separating portion is
By releasing the holding of the developing unit, the developing unit can be moved from the developing separation position to the developing position.
The transfer separation portion is
A process cartridge, wherein the transfer roller can be moved to the transfer position by releasing the holding of the transfer roller. An end member provided at an axial end of the electrophotographic photosensitive drum;
An engaged portion provided on the end member;
An engagement portion and an elastic deformation portion provided to the separation member;
Have
The spacing member is in the first position,
The engagement portion engages with the engaged portion by rotation of the electrophotographic photosensitive drum, whereby the separation member starts moving from the first position to the second position.
The elastically deformable portion is elastically deformed along with the movement of the separation member from the first position to the second position,
The separating member is in the second position,
The engagement between the engaging portion and the engaged portion is released by a force at which the elastic deformation of the elastic deformation portion is restored.
The process cartridge according to claim 1,   The process cartridge according to claim 1, wherein the spacing member is provided at both ends of an end of the electrophotographic photosensitive drum in the rotational axis direction.