JP2016110134A - Process cartridge, image forming apparatus, and separation member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform the separation of a process member acting on an image carrier from the image carrier and the release of the separation.SOLUTION: A process cartridge includes a drum 62 (image carrier), a separation member 48, and a movable operating part for moving the separation member 48. The separation member 48 includes a separation part 48a (first separation part) for separating a developing roller 32 (first process member) from the drum 62 and a regulation part 48b (second separation part) for separating a transfer roller 7 (second process member) from the drum 62. The separation member 48 takes a holding position where the developing roller 32 and the transfer roller 7 are held in a separated state from the drum 62 and an allowable position for allowing the developing roller 32 and the transfer roller 7 to approach the drum 62. The movable operating part is engaged with the separation member 48, to move the separation member 48 from the holding position to the allowable position, according to the rotation of the drum 62.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a process cartridge, an image forming apparatus, and a separation member.

  Here, the process cartridge is a cartridge in which an image carrier and a process member (process means) acting on the image carrier are integrated into a cartridge and detachably attached to the main body (device main body) of the image forming apparatus. It is what is done.

  An image forming apparatus forms an image on a recording medium.

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

  In an electrophotographic image forming apparatus (hereinafter, also simply referred to as “image forming apparatus”), an electrophotographic photosensitive member that is generally a drum type as an image carrier, that is, a photosensitive drum is uniformly charged. Next, an electrostatic latent image (electrostatic image) is formed on the photosensitive drum by selectively exposing the charged photosensitive drum. Next, the electrostatic latent image formed on the photosensitive drum is developed as a toner image with toner as a developer. The toner image formed on the photosensitive drum is transferred to a recording material such as recording paper or a plastic sheet, and the toner image is further transferred to the recording material by applying heat or pressure to the toner image transferred onto the recording material. The image is recorded by fixing it to the surface.

  Such an image forming apparatus generally requires toner replenishment and maintenance of various process means.

  In order to facilitate this toner replenishment and maintenance, the photosensitive drum, charging means, developing means, cleaning means, etc. are put together into a cartridge to form a cartridge, and a process cartridge that can be attached to and detached from the image forming apparatus main body is put into practical use. Has been.

  In order to protect the photosensitive drum during distribution of process cartridges, a separation member that separates the photosensitive drum and the developing roller is known (see Patent Document 1).

JP2012-3243 (FIG. 1)

  The present invention is a further development of the above technique. An object of the present invention is to separate an image carrier and a process member acting on the image carrier, and to release them.

In order to achieve the above object, a typical configuration according to the present invention is as follows.
In a process cartridge that can be attached to and detached from the main body of an image forming apparatus,
An image carrier for carrying an image;
A separation member for separating a process member acting on the image carrier from the image carrier;
A moving action part for moving the spacing member;
Have
The spacing member is
A first separation portion for separating the first process member from the image carrier;
A second separation portion for separating a second process member different from the first process member from the image carrier;
With
A holding position for holding the first process member and the second process member separated from the image carrier by the first separation part and the second separation part; and the first process member and the second process member An allowable position for allowing the image carrier to approach the image carrier,
The moving action part moves the spacing member from the holding position to the permissible position as the image carrier rotates by engaging with the spacing member.

  As described above, according to the invention of the present application, the image carrier and the process member acting on the image carrier can be separated and released.

FIG. 4 is a side view of a state where a process cartridge is mounted on the apparatus main body as viewed from the drive side of the apparatus main body. 2 is a cross-sectional view of an image forming apparatus main body and a process cartridge. FIG. It is sectional drawing of a process cartridge. It is sectional drawing inside the cleaning container of a process cartridge. 1 is a perspective view of an image forming apparatus main body. 1 is a perspective view of an image forming apparatus main body. 2 is a perspective view of an image forming apparatus main body and a process cartridge. FIG. FIG. 4 is a perspective view of a process cartridge and a drive side positioning portion of the image forming apparatus main body. FIG. 4 is a perspective view of a non-driving side positioning portion of a process cartridge and an image forming apparatus main body. It is an exploded view of a process cartridge. It is an exploded view of a process cartridge. It is an exploded view of a process cartridge. It is an exploded view of a process cartridge. It is the perspective view which showed the separation member. FIG. 6 is a perspective view illustrating that a separation member is attached to a process cartridge. It is the schematic side view seen from the drive side explaining the state to which the separation member was attached. It is the schematic side view seen from the drive side explaining the process in which the separation member moves from the first position to the second position. It is explanatory drawing explaining the moving structure of a developing unit.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  Note that the direction of the axis of rotation of the electrophotographic photosensitive drum is the longitudinal direction.

  In the longitudinal direction, the side on which the electrophotographic photosensitive drum receives driving force from the image forming apparatus main body is defined as a driving side, and the opposite side is defined as a non-driving side.

  The overall configuration and the image forming process will be described with reference to FIGS.

  FIG. 2 is a cross-sectional view of an image forming apparatus main body (hereinafter referred to as apparatus main body A) and a process cartridge (hereinafter referred to as 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 obtained by removing the cartridge B from the electrophotographic image forming apparatus.

<Entire configuration of electrophotographic image forming apparatus>
The electrophotographic image forming apparatus shown in FIG. 2 is a laser beam printer using an electrophotographic technique in which a cartridge B is detachable from the apparatus main body A. When the cartridge B is mounted on the apparatus main body A, an exposure device 3 (laser scanner unit) for forming a latent image on the electrophotographic photosensitive drum 62 of the cartridge B is disposed. In addition, a sheet tray 4 that stores a recording medium (hereinafter referred to as a sheet material P) that is an image forming target is disposed below the cartridge B.

  Further, the apparatus main body A includes a pickup roller 5a, a feeding roller pair 5b, a conveyance roller pair 5c, a transfer guide 6, a transfer roller 7, a conveyance guide 8, a fixing device 9, along the conveyance direction D of the sheet material P. A pair of discharge rollers 10, a 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 drum 62) is rotationally driven in the direction of arrow R with a predetermined peripheral speed (process speed).

  The charging roller 66 to which the bias voltage is applied contacts the outer peripheral surface of the drum 62 and uniformly charges the outer peripheral surface of the drum 62.

  The exposure device 3 outputs a laser beam L corresponding to the image information. The laser light 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. As a result, 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 a 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. Then, it is sent out to the toner supply chamber 28. The developing unit 20 supports the developing roller 32.

  The toner T is carried on the surface of the developing roller 32 by the magnetic force of the magnet roller 34 (fixed magnet) disposed inside the developing roller 32. The developing roller 32 is a developer carrier that carries a developer. The developing roller 32 is a process member (first process member) that acts on the drum 62.

  The layer thickness of the toner T on the peripheral surface of the developing roller 32 is regulated while being frictionally charged by the developing blade 42.

  The toner T is supplied from the developing roller 32 to the electrostatic latent image on the drum 62. As a result, the latent image on the drum 62 is developed as a toner image (developer image) and visualized. The drum 62 is an image carrier that carries an image (toner image, developer image).

  Further, as shown in FIG. 2, the sheet material P stored in the lower part of the apparatus main body A is moved to the sheet tray by the pickup roller 5a, the feeding roller pair 5b, and the conveying roller pair 5c in accordance with the output timing of the laser beam L. 4 is sent out. 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 images are sequentially transferred from the drum 62 to the sheet material P. The transfer roller 7 is a transfer member that transfers the toner image (developer image) formed on the drum 62 to the sheet material P. The transfer roller 7 is a process member (second process member) that acts on the drum 62.

  In this embodiment, since the direct transfer configuration is adopted, the transfer material to which the toner image is transferred from the drum 62 by the transfer roller 7 is the sheet material P. However, it is not necessary to transfer the toner image directly from the drum 62 to the sheet material P. For example, when an intermediate transfer belt (intermediate transfer member) is employed as the transfer target, the toner image is primarily transferred from the drum 62 to the intermediate transfer belt by the transfer roller 7. A configuration in which the toner image is secondarily transferred from the intermediate transfer belt to the sheet material P by a secondary transfer roller is also conceivable.

  The sheet material P to 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. The sheet material P passes through the nip portion between the heating roller 9a and the pressure roller 9b constituting the fixing device 9. A pressure / heat fixing process is performed in the nip portion, and the toner image is fixed on the sheet material P. The sheet material P that has undergone the toner image fixing process 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 the transfer is used again in the image forming process after the residual toner on the outer peripheral surface is removed by the cleaning blade 77. The toner removed from the drum 62 is stored in the waste toner chamber 71 b of the cleaning unit 60. The cleaning unit 60 is an image carrier unit (drum unit) that supports a drum (image carrier) 62.

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

<Removal of cartridge>
Next, attachment / detachment of the cartridge B to / from the apparatus main body A will be described with reference to FIGS.

  FIG. 5 is a perspective view of the apparatus main body A with the open / close door 13 opened in order to attach and detach the cartridge B. FIG. FIG. 6 is a perspective view of the apparatus main body A and the cartridge B in a state in which the opening / closing 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 with the open / close door 13 opened and the tray 18 pulled out. The cartridge B can be attached to and detached from the tray 18 along the attaching / detaching direction E.

  An opening / closing door 13 is rotatably attached to the apparatus main body A, and a cartridge insertion opening 17 is provided when the opening / closing door 13 is opened. A tray 18 for mounting the cartridge B to the apparatus main body A is provided in the cartridge insertion opening 17. 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 figure while being placed on the tray 18.

  In addition, a first drive shaft 14 and a second drive shaft 19 for transmitting 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. As a result, the drum 62 connected to the first coupling 70 is rotated by receiving a driving force from the apparatus main body A. Further, the driving force is transmitted from the second coupling 21, and the developing roller 32 rotates. 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 a drive side first support portion 15 a, a drive side second support portion 15 b and a rotation support portion 15 c of the cartridge B. The non-driving side plate 16 is provided with a non-driving side first support portion 16a, a non-driving side second support portion 16b, and a rotation support portion 16c.

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

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

  The cartridge B has a cleaning unit 60 and a developing unit 20. In general, a process cartridge is a cartridge in which at least one of an electrophotographic photosensitive member and a process means (process member) acting on the electrophotographic photosensitive member is integrally formed, and is removable from the main body of the electrophotographic image forming apparatus. It is what.

  Examples of process members include charging means, developing means, and cleaning means.

  The process cartridge has a cleaning unit 60.

  As shown in FIG. 3, the cleaning unit 60 includes a drum 62, a charging roller 66, a cleaning member 77, a cleaning frame body 71 that supports them, and a lid member 72 fixed to the cleaning frame body 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.

  The cleaning member 77 includes a rubber blade 77a that is a blade-like elastic member formed of rubber as an elastic material, and a support member 77b that supports the rubber blade. The rubber blade 77 a is in contact with the drum 62 in the counter direction with respect to the rotation direction of the drum 62. That is, the rubber blade 77 a is in contact with the drum 62 so that the tip end portion thereof faces the upstream side in the rotation 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 a first screw 86, a second screw 87, and a third screw 88 as waste toner conveying members. . The conveyed waste toner is stored in a waste toner chamber 71 b formed by the cleaning frame 71 and the lid member 72.

  Further, the first screw 86 is rotated by a drive transmitted from the coupling 21 shown in FIG. 13 by a gear (not shown). The second screw 87 receives the driving force from the first screw 86 and the third screw 88 rotates from the second screw 87, respectively. 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 rotation axes of the first screw 86 and the third screw 88 are parallel to the rotation axis of the drum 62, and the rotation axis of the second screw 87 is orthogonal to the rotation axis of the drum 62.

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

  The drum 62 is rotationally driven in the direction of arrow R in the drawing according to an image forming operation by receiving a driving force from a main body driving motor (not shown) as a driving source.

  The charging roller 66 is rotatably attached to the cleaning unit 60 via a charging roller bearing 67 at both ends in the longitudinal direction of the cleaning frame 71 (substantially parallel to the rotation 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 rotates following the rotation of the drum 62.

  As shown in FIG. 3, the developing unit 20 includes a developing roller 32, a developing container 23 that supports the developing roller 32, a developing blade 42, and the like. A magnet roller 34 is provided in the developing roller 32. In the developing unit 20, a developing blade 42 for restricting the toner layer on the developing roller 32 is disposed. As shown in FIGS. 10 and 12, a spacing member 38 is attached to the developing roller 32 at both ends of the developing roller 32, and the spacing roller 38 and the drum 62 abut so that the developing roller 32 is a drum. 62 and a slight gap. Further, as shown in FIG. 3, a blowout prevention 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 contact the developing roller 32. Further, the toner chamber 29 formed by the developing container 23 and the bottom member 22 is provided with a first transport member 43, a second transport member 44, and a third transport member 50. The first conveyance member 43, the second conveyance member 44, and the third conveyance 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 lid member 72, a drum 62, and a drum bearing 73 and a drum shaft 78 for rotatably supporting the drum 62. As shown in FIG. 13, a drive-side drum flange 63 as an end member is provided at the end of the drum 62 on the drive side. The drive side drum flange 63 is rotatably supported by the hole 73 a of the drum bearing 73.

  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. It is the structure which supports to.

  As shown in FIGS. 3, 10, and 12, the developing unit 20 includes 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 bearing members 27 and 37 provided at both ends.

  Then, as shown in FIGS. 11 and 13, the cartridge B is configured by coupling the cleaning unit 60 and the developing unit 20 so as to be rotatable with a coupling pin 69.

  Specifically, the development container 23 is provided with a development first support hole 23 a and a development second support hole 23 b at both ends in the longitudinal direction of the development unit 20. In addition, a first suspension hole 71 i and a second suspension hole 71 j are provided in the cleaning frame 71 at both longitudinal ends of the cleaning unit 60. The coupling unit 69 press-fitted and fixed in the first suspension hole 71i and the second suspension hole 71j is fitted with the development first support hole 23a and the development second support hole 23b, so that the cleaning unit 60 and the development unit 20 are rotated with each other. It is linked movably.

  The first hole 46Ra of the driving 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 driving side developing side member 26.

  Further, the first hole 46Fa of the non-driving side urging 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 this embodiment, the driving side urging member 46R and the non-driving side urging member 46F are formed by tension springs. The developing unit 20 is urged toward the cleaning unit 60 by the urging force of the spring so that the developing roller 32 is surely pressed toward the drum 62. The developing roller 32 is held at a predetermined interval from the drum 62 by a spacing holding member 38 attached to both ends of the developing roller 32.

<Development unit movement configuration>
Next, a configuration in which the developing unit 20 moves with respect to the cleaning unit 60 will be described with reference to FIG. As described above, the developing roller 32 is held at a predetermined interval from the drum 62 by the interval holding member 38 attached to both ends contacting the drum 62.

  However, if vibration or impact (for example, due to physical distribution) is applied to the cartridge B in this state, the contact portion of the spacing member 38 or the drum 62 may be deformed or damaged.

  Therefore, in the cartridge B of this embodiment, when not in use, the developing roller 32 is separated from the drum 62 so that the spacing member 38 does not come into contact with the drum 62.

  The developing unit 20 is configured to rotate in the direction of the arrow F around the developing first support hole 23a (and the developing second support hole 23b). When the developing unit 20 rotates in the direction of arrow F, the spacing member 38 provided on the developing roller 32 is separated from the drum 62 (FIG. 18B).

  This is a state in which the developing unit 20 has moved to the separated position. The separation position is a position for increasing the distance between the developing roller 32 and the drum 62 when the cartridge B is not used (during non-image formation) than when the cartridge B is used (during image formation). is there.

  On the other hand, when the image forming operation is performed, the developing unit 20 is held at a position where the spacing member 38 contacts the drum 62 (FIG. 18A). That is, the developing unit 20 is moved to the image forming position (developing position) as shown in FIG. The image forming position is a position (developing position) where the developing unit 20 develops the latent image on the drum 62 by the developing roller 32. When the developing unit 20 is at the image forming position, the developing roller 32 supplies developer to the latent image on the drum 62 and forms a developer image (toner image) on the drum 62.

  In this embodiment, the developing unit 20 is held in the separated position by the separating member 48, and will be described in detail below.

<Configuration of spacing member>
Next, the spacing member 48 will be described in detail with reference to FIGS. FIG. 14 is a perspective view showing the separation member 48. FIG. 15 is a perspective view illustrating that the separation member 48 is attached to the process cartridge B. FIG.

  As shown in FIG. 14, the spacing member 48 has a spacing portion (first spacing portion) 48a, a regulating portion (second spacing portion) 48b, and a guided portion 48c.

  And it has the circular-arc-shaped elastic deformation part 48d in the outer side of the to-be-guided part 48c. Further, a groove portion 48h is formed in a space between the guided portion 48c and the elastic deformation portion 48d.

  A part of the elastically deforming part 48d has a convex part 48e protruding into the groove part 48h.

  And it has the to-be-engaged part 48f engaged with the engaging part 63a provided in the drive side drum flange 63 of the drum 62 mentioned later.

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

  Next, the separation member 48 is attached to the process cartridge B by inserting the separation 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). The developing unit 20 is provided with a restricting portion 20 b that restricts the separation portion 48 a from moving outward in the axial direction of the drum 62. The separation portion 48a does not come off when a vibration or drop impact is applied.

  Although the function will be described later, the drum 62 has a drive-side drum flange 63 as an end member at the end of the axis, and a part thereof has an engaging portion 63a.

  FIG. 1 is a side view of the state in which the separation member 48 is attached to the process cartridge B and attached to the apparatus main body A as viewed from the drive side of the apparatus main body A.

  The separating member 48 is movable because a guided portion 48c is rotatably supported around the axis of the drum 62 along the guide portion 60b. The separating member 48 that moves in the present description is movable between a first position (holding position) and a second position (allowable position).

  The first position (holding position) of the spacing member 48 is a position where the spacing member 48 holds the developing unit 20 such that the developing roller 32 is spaced from the drum 62. The first position (holding position) is a position where the separating member 48 regulates the transfer roller 7 so that the transfer roller 7 is separated from the drum 62.

  The second position (allowable position) of the separating member 48 is a position where the separating member 48 releases the holding of the developing unit 20, and is a position that allows the developing roller 32 to move to the image forming position. Further, the allowable position is a position where the separating member 48 releases the restriction of the transfer roller 7 and is a position where the transfer roller 7 is allowed to come into pressure contact with the drum 62.

  With reference to FIG. 1, 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.

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

[Development roller separation]
FIG. 1A shows a state in which the separation member 48 is in the first position (holding position).

  A separation portion (first separation portion) 48 a of the separation 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 has the first suspension hole 71i and the second suspension hole 71j (not shown) provided in the cleaning frame body 71 of the cleaning unit 60 as described above as the center of rotation by the thickness of the inserted separation portion 48a, and an arrow. It is rotated and held in the V1 direction. In this state, the distance between the surface of the developing roller 32 and the surface of the drum 62 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 from each other, or are in contact with each other at a pressure lower than that required for image formation. By inserting the separating portion 48a, the distance between the drum 62 and the developing roller 32 is separated from the distance necessary for image formation. This is the separated state of the developing roller 32. When the separation member 48 is in the first position (FIG. 1A), the distance between the developing roller 32 and the drum 62 (both of them) is greater than when the separation member 48 is in the second position (FIG. 1B: described later). (Center-to-center distance or surface-to-surface distance) increases.

[Development roller separation release]
FIG. 1B shows a state in which the separation member 48 is in the second position.

  When the separation member 48 moves from the first position to the second position, the separation portion 48a moves to a position away from the contact portion 20a. Since the contact between the separation portion 48a and the contact portion 20a is eliminated, the developing unit 20 has a first suspension hole 71i and a second suspension hole 71j (not shown) provided in the cleaning frame 71 of the cleaning unit 60 described above. It is possible to rotate in the direction of the drum 62 (the direction of the arrow V2) about the rotation center.

  As the developing unit 20 rotates, the developing roller 32 is pressed toward the drum 62 by the urging force of the driving side urging member 46R and the non-driving side urging member 46F, and is attached to both ends of the developing roller 32. The holding member 38 contacts the drum 62. The surface of the developing roller 32 and the surface of the drum 62 remain at a predetermined interval (l2). This is a state where the separation of the developing roller 32 is released. That is, the developing roller 32 can act on the drum 62. When the developing roller 32 is in this state, the latent image (electrostatic latent image) formed on the drum 62 can be developed with a developer (toner).

<Separation of drum and transfer roller and release of separation>
Next, the 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 a state in which the separation member 48 is in the first position.

  The transfer roller 7 has an elastic roller portion 7b that can rotate around a metal core 7a. The elastic roller portion 7b is pressed against the drum 62 by urging it in the direction of the drum 62 by a spring (not shown) through a bearing (not shown) that rotatably supports the core metal 7a. Yes. The metal core 7a is movable in the direction of arrow S within the urging range of a spring (not shown).

  When the process cartridge B with the spacing member 48 in the first position is mounted on the apparatus main body A, the restricting portion (second spacing portion) 48b and the cored bar 7a at both ends of the transfer roller 7 are in contact with each other. It has become.

  As the process cartridge B is mounted in the mounting direction (arrow C), the restricting portion 48b pushes down 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 keeps the elastic roller portion 7b of the transfer roller 7 away from the surface of the drum 62 or in a state where it is in contact with a pressure lower than that during pressure contact during image formation. This is the separated state of the transfer roller 7. When the separating member 48 is in the first position (FIG. 1A), the distance between the transfer roller 7 and the drum 62 (between the centers of both) is larger than when the separating member 48 is in the second position (FIG. 1B). Distance or distance between surfaces) increases.

[Release release of transfer roller]
As described above, FIG. 1B shows a state in which the separation member 48 is in the second position.

  As the spacing member 48 moves from the first position to the second position, the restricting portion 48b moves to a position away from the cored bar 7a. Since the contact between the restricting 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 pressed against the drum 62, and the transfer roller 7 remains at the image forming position. This is a state where the separation of the transfer roller 7 is released. That is, the transfer roller 7 can act on the drum 62. When the transfer roller 7 is in this state, the developer image (toner image) carried on the drum 62 can be transferred to the transfer target (sheet material P).

  When the separating member 48 having the above-described contents is in the first position, two parts, that is, the separation of the developing roller 32 from the drum 62 and the separation of the transfer roller 7 from the drum 62 are simultaneously performed with one component. Is possible.

  When the process cartridge B is transported while being attached to the apparatus main body A, the separation 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, and the surface of the transfer roller 7 are subjected to an impact or vibration due to physical distribution in this state. It is possible to prevent damage to the surface.

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

<Movement of separation member from first position to second position>
Next, the movement of the separation member 48 from the first position to the second position will be described in detail.

  A state in which the separating member 48 moves from the first position (FIG. 16) to the second position (FIG. 17C) will be described with reference to FIGS.

  FIG. 16 is a schematic side view of the apparatus main body A as viewed from the driving side, explaining the state in which the separation member 48 is attached. FIG. 17 is a schematic side view seen from the driving side of the apparatus main body A, illustrating the process in which the separation member 48 moves from the first position to the second position.

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

  As described above, the separation member 48 is attached by inserting the groove portion 48h formed in the space between the guided portion 48c and the elastic deformation portion 48d into the attachment portion 60a.

  The spacing member 48 can be rotated about the axis of the drum 62 by guiding the guided portion 48c by the guide portion 60b.

  And the guide part 60b is circular arc shape provided in the range of angle (alpha) centering on the drum 62 axis line. That is, it is a curved guide along the rotation direction of the drum 62. And the guide part 60b has the end point 60c in the drum 62 rotation direction R downstream side. Furthermore, the guide part 60b has an attachment part 60a at its tip.

  The spacing member 48 is provided with a locked portion 48g that engages with the mounting portion 60a at the tip of the elastic deformation portion 48d. The engagement between the attachment portion 60a and the locked portion 48g prevents the separation member 48 from rotating in the direction opposite to the rotation direction R of the drum 62 when the separation member 48 is in the first position (holding position).

  That is, the attachment portion 60a is a locking portion (first locking portion) that suppresses the separation member 48 from moving from the first position to the upstream side (opposite side) in the drum rotation direction R. The locked portion 48g is a locked portion (first locked portion) whose movement is suppressed by engaging with the attachment portion 60a when the separating member 48 is in the first position.

  If the width of the groove 48h is W1, the width of the groove 48h 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, a distance from the axis (center) of the drum 62 to the engaging portion 63a provided on the drum flange 63 is r1, and a distance from the axis of the drum 62 to the engaged portion 48f of the separating member 48 is r2. The relationship between the distance r1 and the distance r2 is r1> r2.

  As shown in FIG. 17A, when the drum 62 rotates in the R direction, the engaging portion 63a and the engaged portion 48f come into contact with each other. Then, when the rotation of the drum 62 continues, the engaging portion 63a applies a force to the engaged portion 48f. As described above, since the guided portion 48c of the separation member 48 is guided by the guide portion 60b, the separation member 48 starts to rotate in the rotation direction R about the drum 62 axis.

  That is, the engaging part 63a is a moving action part that applies a force to the engaged part 48f by engaging with the engaged part 48f and moves the separation member 48. The engaged portion 48f is a moved action portion that receives a force for moving the separating member 48 from the engaging portion 63a.

  As shown in FIG. 17B, when the movement of the separating member 48 further proceeds, the projection 48e in the groove 48h and the mounting portion 60a come into contact with each other.

  As described with reference to FIG. 16, the width W2 of the groove 48h and the width W3 of the mounting portion 60a have a relationship of W3> W2. Therefore, the convex part 48e receives force from the attachment part 60a when it tries to contact the attachment part 60a and get over it. By this force, the elastic deformation portion 48 starts elastic deformation and deforms outward in the radial direction of the drum 62 (arrow Q side).

  When the elastic deformation portion 48 is deformed toward the outer side in the radial direction of the drum 62, the convex portion 48e provided on the elastic deformation portion 48 gets over the attachment portion 60a (FIG. 17B). That is, the convex part 48e passes the attachment part 60a. Then, the separation member 48 continues to move toward the second position.

  The attachment portion 60a is a deformation acting portion that applies a force for deforming the elastic deformation portion 48 to the convex portion 48e. The convex portion 48e is a deformed acting portion that receives a force for deforming the elastic deformation portion 48 from the attachment portion 60a.

  When the elastically deforming portion 48d is in a state of being elastically deformed, the guided portion 48c reaches the end point 60c of the guide portion 60b.

  As shown in FIG. 17 (c), the protrusion 48 e gets over the attachment portion 60 a, so that the separation member 48 is prevented from rotating in the direction opposite to the rotation direction R of the drum 62. At the same time, the protruding portion 48e abuts against the guide portion 60b, whereby the posture of the separating member 48 is regulated, and the separating member 48 is held at the second position (allowable position).

  The attachment portion 60a is a locking portion (second locking portion) for suppressing the separation member 48 in the second position from moving toward the upstream side (opposite side) in the rotation direction R. On the other hand, the convex portion 48e is a locked portion (second locked portion) whose movement is suppressed by the mounting portion 60a when the separating member 48 is in the second position.

  In addition, although the convex part 48e serves as a to-be-deformed action part, you may be comprised in the part from which a 2nd to-be-latched part and a to-be-deformed action part differ.

  Further, as described above, the attachment portion 60a also prevents the separation member 48 from moving from the first position toward the upstream in the rotation direction R (see FIG. 16). That is, the attachment portion 60a includes a locking portion (first locking portion) that suppresses the separation member 48 from moving from the first position, and a locking portion (first locking portion) that prevents the separation member 48 from moving from the second position. This is a structure that also serves as two locking portions. Furthermore, the attachment portion 60a also serves as a deformation action portion for deforming the elastic deformation portion 48d. However, the first locking portion, the second locking portion, and the deformation acting portion may be configured with different portions.

  In a state where the movement of the convex portion 48e is restricted by the attachment portion 60a and the guide portion 60b (a state in which the separation member 48 is in the second position), the distance from the axis of the drum 62 to the convex portion 48e is r4. Further, as described with reference to FIG. 16, the distance from the axis of the drum 62 to the convex portion 48e when the separating member 48 is in the first position is r3. At this time, the relationship between the distance r4 and the distance r3 is r4> r3.

  That is, when the separation member 48 moves to the second position, the convex portion 48 e is held at a position away from the center of the drum 62 toward the outside in the radial direction of the drum 62.

  When the separation member 48 moves to the second position, the guided portion 48c cancels the state guided by the guide portion 60b. That is, the two do not come into contact with each other (FIG. 17C).

  The guided portion 48c is elastically deformed when guided by the guide portion 60b, but when the guide state is canceled, the elastic deformation is also canceled and the original shape is restored. At this time, since the convex portion 48e is used as a fixed point and the shape returns to the original shape, the guided portion 48c moves together with the convex portion 48e in the outer direction (arrow Q) in the radial direction of the drum 62. At the same time, the engaged portion 48f also moves in the arrow Q direction.

  As a result, the distance from the axis of the drum 62 to the engaged portion 48f is r5. That is, the distance from the axis of the drum 62 to the engaged portion 48f is greater when the spacing member 48 is in the second position (FIG. 17C) than when the spacing member 48 is in the first position (FIG. 16). )) Is longer (r2 <r5).

  The relationship between the distance r1 (FIG. 16) from the axis of the drum 62 to the engaging portion 62b and the distance r5 is r1 <r5.

  For this reason, the engaged portion 48f and the engaged portion 62b are disengaged from each other, and the two do not contact each other. That is, when the separation member 48 moves to the second position, the rotation of the drum 62 is not transmitted to the separation member 48, and the separation member 48 does not move further from the second position.

  Finally, the configuration of this embodiment is summarized as follows.

  The process cartridge B includes a drum 62, a separation member 48, and an engaging portion 63a. The drum 62 is an image carrier that carries an image (toner image, developer image). The separation member 48 is for separating the process members (the developing roller 32 and the transfer roller 7) from the drum 62. The engaging portion 63a is a moving action portion that moves the separating member 48.

  The separation member 48 includes a separation portion (first separation portion) 48a for separating the developing roller 32 (first process member) and a regulation portion (second separation) for separating the transfer roller 7 (second process member). Part) 48b.

  The spacing member 48 can take a first position (holding position) where the developing roller 32 and the transfer roller 7 are separated from the drum 62 by the spacing portion 48a and the regulating portion 48b (see FIG. 1A). In addition, the separation member 48 can take a second position (allowable position) that allows the developing roller 32 and the transfer roller 7 to approach the drum 62 (FIG. 1B).

  The engaging portion 63a engages with the engaged portion 48f of the separating member 48 to move the separating member 48 as the drum 62 rotates in the direction of arrow R in FIG. That is, the engaging part 63a moves the separating member 48 from the first position (FIGS. 1A and 16) to the second position (FIGS. 1B and 17C).

  More specifically, the process cartridge B has a developing unit 20 that supports the developing roller 32 and a cleaning unit (image carrier unit) 60 that supports the drum 62 (see FIG. 3).

  The development unit 20 moves with respect to the cleaning unit 60, and can take a development position (FIGS. 18A and 1B) and a separation position (FIGS. 18B and 1A). . The development position is a position at which the latent image formed on the drum 62 can be developed by the development roller 32. On the other hand, the separation position is a position where the developing roller 32 is separated from the drum 62 rather than the development position.

  When the separation member 48 moves from the first position (FIGS. 1A and 16) to the second position (FIGS. 1B and 17C), the developing unit 20 is separated (FIG. 18). (B) Move from FIG. 1 (a) to the development position (FIG. 18 (a), FIG. 1 (b)).

  According to the configuration described above, the drum 62 and the process member can be separated by the separation member 48 during the distribution (transport) of the cartridge B or the image forming apparatus in which the cartridge B is mounted. This can prevent the drum 62 and the process member from being damaged.

  In the present embodiment, the plurality of process members can be separated from the drum 62 at a time by the separation member 48. Since it is not necessary to provide a plurality of separation members corresponding to each process member, it contributes to downsizing and cost reduction of the process cartridge B and the image forming apparatus.

  In addition, although the developing roller 32 and the transfer roller 7 were illustrated as an example of a process member, it is not restricted to this. For example, the separation member 48 may be configured to separate the charging roller 66 (FIG. 3) as a process member.

  Then, the separation member 48 can be moved from the first position to the second position by the rotation of the drum 62 of the process cartridge B.

  That is, by rotating the drum 62, it is possible to release the separation between the drum 62 and the developing roller and release the separation between the drum 62 and the transfer roller 7 at a time.

  In this embodiment, the description has been made on the assumption that the cartridge B includes the drum 62 and the developing roller 32 and the cartridge B can be attached to and detached from the apparatus main body A. However, the drum 62 and the developing roller 32 are not necessarily detached from the apparatus main body A.

  For example, the drum 62 and the developing roller 32 may not be removed from the apparatus main body A. Even in that case, it is possible to protect the drum 62 by separating the process member (the developing roller 32 and the transfer roller 7) from the drum 62 by the separating member 48 when the image forming apparatus is transported.

  Further, the separation members 48 may be provided at both ends of the cartridge B in the axial direction of the drum 62.

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

7 Transfer roller (second process member, transfer member)
32 Developing roller (first process member, developer carrier)
48 spacing member 48a spacing portion (first spacing portion)
48b Restriction part (second separation part)
62 drum (image carrier)
63a Engagement part (moving action part)
A Image forming apparatus body (apparatus body)
R direction of rotation

Claims (19)

In a process cartridge that can be attached to and detached from the main body of an image forming apparatus,
An image carrier for carrying an image;
A separation member for separating a process member acting on the image carrier from the image carrier;
A moving action part for moving the spacing member;
Have
The spacing member is
A first separation portion for separating the first process member from the image carrier;
A second separation portion for separating a second process member different from the first process member from the image carrier;
With
A holding position for holding the first process member and the second process member separated from the image carrier by the first separation part and the second separation part; and the first process member and the second process member An allowable position for allowing the image carrier to approach the image carrier,
The process cartridge according to claim 1, wherein the moving action portion engages with the separation member to move the separation member from the holding position to the permissible position as the image carrier rotates. The separation member includes a moved action portion that receives a force for moving from the holding position to the allowable position by engaging with the movement action portion,
2. The process cartridge according to claim 1, wherein engagement of the moved action portion and the movement action portion is released in a state where the separation member is moved to the permissible position.   The said movement action part cancels | releases engagement with the said movement action part by deform | transforming in the process in which the said separation member moves from the said holding position to the said permissible position. Process cartridge.   4. The distance from the axis of the image carrier to the moving action portion is longer when the separating member is at the allowable position than when the separating member is at the holding position. Process cartridge according to.   5. The process cartridge according to claim 2, further comprising a restricting portion that restricts outward movement of the first separation portion with respect to an axial direction of the image carrier.   The process according to any one of claims 1 to 5, further comprising a guide portion that guides the separation member from moving from the holding position to the permissible position by being in contact with the separation member. cartridge.   The guide portion engages with a first locked portion provided on the separation member, thereby suppressing the movement of the separation member from the holding position to the upstream side in the rotation direction of the image carrier. The process cartridge according to claim 6, further comprising one locking portion.   The guide portion engages with a second locked portion provided on the separation member, thereby suppressing the movement of the separation member from the holding position to the upstream side in the rotation direction of the image carrier. 8. The process cartridge according to claim 6, further comprising two locking portions.   9. The cartridge according to claim 8, wherein the second locked portion passes through the second locking portion when the separation member is deformed in the process of moving from the holding position to the permissible position. . The process cartridge has a developer carrier that carries a developer for developing a latent image formed on the image carrier,
The process cartridge according to claim 1, wherein the first process member is the developer carrying member. The process cartridge is
A developing unit for supporting the developer carrier;
An image carrier unit for supporting the image carrier;
Have
The developing unit moves with respect to the image carrier unit, so that the latent image can be developed by the developer carrier, and the developer carrier is placed closer to the image carrier than the development position. A separation position away from
The process cartridge according to claim 10, wherein the developing unit moves from the separated position to the developing position when the separating member moves from the holding position to the permissible position.   The process cartridge according to claim 11, wherein the first separation portion is inserted between the development unit and the image carrier unit to hold the development unit at the separation position. The apparatus main body includes a transfer member for transferring a developer image formed on the image carrier to a transfer target,
The process cartridge according to claim 1, wherein the second process member is the transfer member. The process cartridge has an end member provided at an end of the image carrier,
The process cartridge according to claim 1, wherein the moving action portion is provided on the end member.   The process cartridge according to claim 1, wherein the spacing members are provided at both ends of the process cartridge in the axial direction of the image carrier. In an image forming apparatus for forming an image on a recording medium,
An image carrier for carrying an image;
A separation member for separating a process member acting on the image carrier from the image carrier;
A first process member;
A second process member different from the first process member;
A moving action part for moving the spacing member;
Have
The spacing member is
A first separation portion for separating the first process member from the image carrier;
A second separation portion for separating the second process member from the image carrier;
With
A holding position for holding the first process member and the second process member separated from the image carrier by the first separation part and the second separation part; and the first process member and the second process member An allowable position for allowing the image carrier to approach the image carrier,
The image forming apparatus, wherein the moving action unit moves the spacing member from the holding position to the permissible position as the image carrier rotates by engaging with the spacing member.   The image forming apparatus according to claim 16, wherein the image carrier is detachable from the apparatus main body of the image forming apparatus as a part of a process cartridge.   The image forming apparatus according to claim 16, wherein the process cartridge is the process cartridge according to claim 1. In a separation member attached to a process cartridge including an image carrier and separating a process member acting on the image carrier from the image carrier,
A first separation portion for separating the first process member from the image carrier;
A second separation portion for separating a second process member different from the first process member from the image carrier;
A movable action portion that engages with a movement action portion provided in the process cartridge and receives a force for moving the separation member;
Have
The separation member holds the first process member and the second process member separated from the image carrier by the first separation portion and the second separation portion when attached to the process cartridge. A holding position and a permissible position allowing the first process member and the second process member to approach the image carrier;
The moving member is a separating member that receives the force from the moving member as the image carrier rotates, and moves the separating member from the holding position to the permissible position.

Images