JP7179932B2 - Cartridge and image forming device - Google Patents

Description

The present invention relates to an electrophotographic image forming apparatus (hereinafter referred to as an image forming apparatus) and a cartridge that can be attached to and detached from the main body of the image forming apparatus.

Here, the image forming apparatus forms an image on a recording medium using an electrophotographic image forming process. Examples of image forming apparatuses include electrophotographic copiers, electrophotographic printers (eg, laser beam printers, LED printers, etc.), facsimile machines, word processors, and the like.

Further, the cartridge refers to an electrophotographic photosensitive drum (hereinafter referred to as a drum, photoreceptor, or photoreceptor drum) as an image carrier, or process means acting on the drum (for example, a developer carrier (hereinafter referred to as a developing drum). At least one of the rollers)) is made into a cartridge which is detachable from the image forming apparatus. Cartridges include a cartridge in which a drum and a developing roller are integrally formed, and a cartridge in which a drum and a developing roller are separately formed. In particular, the latter having a drum is called a drum cartridge, and the latter having a developing roller is called a developing cartridge.

Further, the image forming apparatus main body is the rest of the image forming apparatus excluding the cartridge.

2. Description of the Related Art Conventionally, an image forming apparatus employs a process cartridge system in which a drum and process means acting on the drum are integrated into a cartridge, and the cartridge is detachable from the main body of the image forming apparatus.

According to this process cartridge system, maintenance of the image forming apparatus can be performed by the user himself/herself without relying on a serviceman, so that the operability can be improved remarkably.

Therefore, this process cartridge system is widely used in image forming apparatuses.

Here, a process cartridge (for example, reference document 1) or an image forming apparatus (for example, reference document 2) provided with a clutch for performing drive switching for driving the developing roller during image formation and interrupting the drive to the developing roller during non-image formation. ) has been proposed.

JP 2001-337511 JP 2003-208024

In Patent Document 1, a spring clutch for switching driving is provided at the end of the developing roller.

Further, in Patent Document 2, the image forming apparatus is provided with a clutch for switching the drive to the developing roller.

SUMMARY OF THE INVENTION It is an object of the present invention to improve the conventional clutch for switching the drive to the developing roller.

In order to achieve the above object, a representative configuration according to the present application is
a developing roller;
a driving input member for receiving driving force for rotating the developing roller from the outside of the cartridge;
a lever movable between a first position and a second position;
has
(a) the drive input member moves toward the outside of the cartridge when the lever moves from the second position to the first position; and (b) the lever moves from the first position to the second position. configured to move toward the interior of the cartridge by moving to a position;
When the cartridge takes a posture in which the developing roller is positioned below the cartridge and the axis of the developing roller is positioned below the axis of the drive input member, the lever is positioned below the cartridge. is located cartridge.

FIG. 2 is an exploded perspective view of the vicinity of the drive connecting portion of the process cartridge according to the first embodiment, viewed from the drive side; Sectional view of the image forming apparatus according to the first embodiment 1 is a perspective view of an image forming apparatus according to a first embodiment; FIG. Sectional view of the process cartridge according to the first embodiment FIG. 2 is an exploded perspective view of the process cartridge according to the first embodiment viewed from the drive side; FIG. 2 is an exploded perspective view of the process cartridge according to the first embodiment viewed from the non-drive side; FIG. 4A is a side view of the process cartridge according to the first embodiment, in which (a) is a contact state between the drum and the developing roller, (b) is a state in which the biasing force receiving portion has moved a distance δ1, and (c) is a biasing force receiving portion. shows a state in which the part has moved a distance δ2 FIG. 2 is an exploded perspective view of the vicinity of the drive connecting portion of the process cartridge according to the first embodiment, viewed from the non-drive side; 4A and 4B are schematic cross-sectional views of the vicinity of the cartridge-side drive transmission member according to the first embodiment, in which (a) shows a drive transmission state and (b) shows a drive interruption state; FIG. 2 is an exploded schematic diagram of a release cam and a developing cover member according to the first embodiment; FIG. 2 is an exploded schematic view of a release cam, a developer cover member, and a drive-side cartridge cover member according to the first embodiment; (a) is a schematic cross-sectional view of the cartridge-side drive transmission member according to the first embodiment, and (b) is a cross-sectional view of the cartridge-side drive transmission member moved in the N direction. FIG. 4A is a schematic cross-sectional view of the drive connection portion, and FIG. 4B is a perspective view of the drive connection portion, in the vicinity of the cartridge-side drive transmission member according to the first embodiment, in a developing contact/drive transmission state; FIG. 4A is a schematic cross-sectional view of the drive connecting portion, and FIG. 7B is a perspective view of the drive connecting portion. FIG. FIG. 4A is a schematic cross-sectional view of the drive connection portion, and FIG. 4B is a perspective view of the drive connection portion, in the vicinity of the cartridge-side drive transmission member according to the first embodiment, in the development separation/drive cutoff state; Schematic diagram of the positional relationship of the release cam, the drive-side cartridge cover member, and the guide for the developer cover member according to the first embodiment. A block diagram of an example of a gear arrangement of an image forming apparatus FIG. 11 is an exploded perspective view of the vicinity of the drive connecting portion of the process cartridge, viewed from the drive side, according to the second embodiment; FIG. 11 is an exploded perspective view of the vicinity of the drive connecting portion of the process cartridge according to the second embodiment, viewed from the non-drive side; 7A and 7B are schematic cross-sectional views of the vicinity of the cartridge-side drive transmission member according to the second embodiment, where (a) shows a drive transmission state and (b) shows a drive interruption state; 7A and 7B are schematic diagrams of the vicinity of the cartridge-side drive transmission member according to the second embodiment in a developer contact/drive transmission state, where (a) is a schematic cross-sectional view of the drive connection portion, and (b) is a perspective view of the drive connection portion; 7A and 7B are schematic diagrams of the vicinity of the cartridge-side drive transmission member according to the second embodiment in the development separation/drive transmission state, where (a) is a schematic cross-sectional view of the drive connection portion, and (b) is a perspective view of the drive connection portion; 7A and 7B are schematic diagrams of the vicinity of the cartridge-side drive transmission member according to the second embodiment in the development separation/drive cutoff state, where (a) is a schematic cross-sectional view of the drive connection portion, and (b) is a perspective view of the drive connection portion; FIG. 11 is an exploded perspective view of the vicinity of the drive connecting portion of the process cartridge according to the third embodiment, viewed from the drive side; FIG. 11 is an exploded perspective view of the vicinity of the driving connection portion of the process cartridge according to the third embodiment, viewed from the non-driving side; (a) Exploded view and (b) perspective view of the idler gear and the cartridge-side drive transmission member according to the third embodiment. 8A and 8B are schematic cross-sectional views of the vicinity of the cartridge-side drive transmission member according to the third embodiment, where (a) shows a drive transmission state and (b) shows a drive cutoff state; FIG. 11 is an exploded perspective view of the vicinity of the drive connecting portion of the process cartridge, viewed from the drive side, according to the fourth embodiment; FIG. 11 is an exploded perspective view of the vicinity of the driving connection portion of the process cartridge according to the fourth embodiment, viewed from the non-driving side; A perspective view of a release cam and a developer cover member according to the fourth embodiment. A perspective view of a cartridge-side drive transmission member, a release member, peripheral parts, and a drive-side cartridge cover member according to the fourth embodiment. A perspective view of a release cam and a developer cover member according to the fourth embodiment. 4A and 4B are schematic cross-sectional views showing the vicinity of a cartridge-side drive transmission member according to a fourth embodiment, where (a) shows a drive transmission state and (b) shows a drive interruption state; 7A and 7B are schematic diagrams of the vicinity of the cartridge-side drive transmission member according to the fourth embodiment in the development contact/drive transmission state, where (a) is a schematic cross-sectional view of the drive connection portion, and (b) is a perspective view of the drive connection portion; 7A and 7B are schematic diagrams of the vicinity of the cartridge-side drive transmission member according to the fourth embodiment in the development separation/drive transmission state, in which (a) is a schematic cross-sectional view of the drive connection portion, and (b) is a perspective view of the drive connection portion; 7A and 7B are schematic diagrams of the vicinity of the cartridge-side drive transmission member according to the fourth embodiment in the development separation/drive cutoff state, where (a) is a schematic cross-sectional view of the drive connection portion, and (b) is a perspective view of the drive connection portion; 4A is an exploded perspective view schematically showing forces acting on the developing unit 9, and FIG. schematic side view A diagram of the developing cartridge D according to the fourth embodiment (a) is an exploded perspective view of the vicinity of the driving connection portion of the developing cartridge according to the fourth embodiment, and (b) is a schematic side view of the driving side along the rotation axis X direction. FIG. 11 is an exploded perspective view of the vicinity of the drive connecting portion of the process cartridge according to the fifth embodiment, viewed from the drive side; FIG. 11 is an exploded perspective view of the vicinity of the driving connection portion of the process cartridge according to the fifth embodiment, viewed from the non-driving side; FIG. 11 is an exploded perspective view of the process cartridge according to the fifth embodiment, viewed from the drive side; FIG. 11 is an exploded perspective view of the process cartridge according to the fifth embodiment as viewed from the non-driving side; A perspective view of a release cam and a drive-side cartridge cover member according to a fifth embodiment. Schematic diagram of drive connecting portion, drive-side cartridge cover member, and bearing member according to the fifth embodiment 5A and 5B are schematic cross-sectional views of the vicinity of a cartridge-side drive transmission member according to a fifth embodiment, where (a) shows a drive transmission state and (b) shows a drive interruption state; 7A and 7B are schematic diagrams of the vicinity of the cartridge-side drive transmission member according to the fifth embodiment in a developer contact/drive transmission state, where (a) is a schematic cross-sectional view of the drive connection portion, and (b) is a perspective view of the drive connection portion; 7A and 7B are schematic diagrams of the vicinity of the cartridge-side drive transmission member according to the fifth embodiment in the development separation/drive transmission state, in which (a) is a schematic cross-sectional view of the drive connection portion, and (b) is a perspective view of the drive connection portion; 7A and 7B are schematic diagrams of the vicinity of the cartridge-side drive transmission member according to the fifth embodiment in the development separation/drive cutoff state, where (a) is a cross-sectional schematic diagram of the drive connection portion, and (b) is a perspective view of the drive connection portion; FIG. 11 is an exploded perspective view of the vicinity of the drive connecting portion of the process cartridge according to the sixth embodiment, viewed from the drive side; FIG. 11 is an exploded perspective view of the vicinity of the driving connection portion of the process cartridge according to the sixth embodiment, viewed from the non-driving side; FIG. 11 is an exploded perspective view of the process cartridge according to the sixth embodiment, viewed from the drive side; FIG. 11 is an exploded perspective view of the process cartridge according to the sixth embodiment as seen from the non-driving side; 6A and 6B are schematic cross-sectional views showing the vicinity of a cartridge-side drive transmission member according to a sixth embodiment, where (a) shows a drive transmission state and (b) shows a drive interruption state; A perspective view of a release cam and a release lever according to the sixth embodiment. A perspective view of a cartridge-side drive transmission member, a release member, peripheral parts, and a drive-side cartridge cover member according to a sixth embodiment. 6A and 6B are schematic diagrams of the vicinity of the cartridge-side drive transmission member according to the sixth embodiment in a developer contact/drive transmission state, where (a) is a cross-sectional schematic diagram of the drive connection portion and (b) is a perspective view of the drive connection portion; 7A and 7B are schematic views of the vicinity of the cartridge-side drive transmission member according to the sixth embodiment in the development separation/drive transmission state, where (a) is a schematic cross-sectional view of the drive connection portion, and (b) is a perspective view of the drive connection portion; 7A and 7B are schematic diagrams of the vicinity of the cartridge-side drive transmission member according to the sixth embodiment in the development separation/drive cutoff state, where (a) is a schematic cross-sectional view of the drive connection portion, and (b) is a perspective view of the drive connection portion; FIG. 11A is an exploded perspective view schematically showing the force acting on the developing unit 9, and FIG. Schematic side view from A perspective view of a release lever release cam and a developer cover member according to the sixth embodiment. 7A and 7B are schematic cross-sectional views of the vicinity of the cartridge-side drive transmission member according to the seventh embodiment, where (a) shows a drive transmission state and (b) shows a drive interruption state;

[Example 1]
[General Description of Electrophotographic Image Forming Apparatus]
A first embodiment of the present invention will be described below with reference to the drawings.

In the following embodiments, a full-color image forming apparatus in which four process cartridges are attachable and detachable is exemplified as an image forming apparatus. The number of process cartridges to be mounted on the image forming apparatus is not limited to this. It is appropriately set as needed. For example, in the case of an image forming apparatus that forms a monochrome image, the number of process cartridges mounted in the image forming apparatus is one. Further, in the embodiments described below, a printer is exemplified as an example of the image forming apparatus.

[Schematic Configuration of Image Forming Apparatus]
FIG. 2 is a schematic cross-sectional view of an electrophotographic image forming apparatus of this embodiment capable of forming an image on a recording medium. FIG. 3A is a perspective view of the image forming apparatus of this embodiment. 4 is a sectional view of the process cartridge P of this embodiment. 5 is a perspective view of the process cartridge P of this embodiment viewed from the driving side, and FIG. 6 is a perspective view of the process cartridge P of this embodiment viewed from the non-driving side.

As shown in FIG. 2, this image forming apparatus 1 is a four-color full-color laser printer using an electrophotographic image forming process, and forms a color image on a recording medium S. As shown in FIG. The image forming apparatus 1 is of a process cartridge type, and forms a color image on a recording medium S by detachably attaching a process cartridge to an electrophotographic image forming apparatus main body 2 .

Here, regarding the image forming apparatus 1, the side on which the front door 3 is provided is the front side (front side), and the side opposite to the front side is the back side (rear side). The right side of the image forming apparatus 1 is called the drive side, and the left side is called the non-drive side. FIG. 2 is a cross-sectional view of the image forming apparatus 1 viewed from the non-driving side. side.

The image forming apparatus main body 2 has four process cartridges: a first process cartridge PY (yellow), a second process cartridge PM (magenta), a third process cartridge PC (cyan), and a fourth process cartridge PK (black). Cartridges P (PY, PM, PC, PK) are arranged horizontally.

Each of the first to fourth process cartridges P (PY, PM, PC, PK) has a similar electrophotographic image forming process mechanism, and uses different developer colors. A rotational driving force is transmitted from the driving output section of the image forming apparatus main body 2 to the first to fourth process cartridges P (PY, PM, PC, PK). Details will be described later.

A bias voltage (charging bias, developing bias, etc.) is supplied from the image forming apparatus main body 2 to each of the first to fourth process cartridges P (PY, PM, PC, PK) (not shown).

As shown in FIG. 4, each of the first to fourth process cartridges P (PY, PM, PC, PK) of this embodiment includes a drum 4 as a photoreceptor and a process means acting on the drum 4. It has a photoreceptor drum unit 8 with charging means and cleaning means.

Each of the first to fourth process cartridges P (PY, PM, PC, PK) has a developing unit 9 having developing means for developing the electrostatic latent image on the drum 4 .

The first process cartridge PY contains yellow (Y) developer in the developing frame 29 and forms a yellow developer image on the surface of the drum 4 .

The second process cartridge PM accommodates a magenta (M) developer in the developing frame 29 and forms a magenta developer image on the surface of the drum 4 .
The third process cartridge PC accommodates cyan (C) developer in the developing frame 29 and forms a cyan developer image on the surface of the drum 4 .

The fourth process cartridge PK accommodates black (K) developer in the developing frame 29 and forms a black developer image on the surface of the drum 4 .

Above the first to fourth process cartridges P (PY, PM, PC, PK), a laser scanner unit LB as exposure means is provided. This laser scanner unit LB outputs a laser beam Z corresponding to image information. The laser beam Z passes through the exposure window 10 of the cartridge P to scan and expose the surface of the drum 4 .

An intermediate transfer belt unit 11 as a transfer member is provided below the first to fourth cartridges P (PY, PM, PC, PK). The intermediate transfer belt unit 11 has a driving roller 13 and tension rollers 14 and 15, and a flexible transfer belt 12 is stretched thereon.

The lower surfaces of the drums 4 of the first to fourth cartridges P (PY, PM, PC, PK) are in contact with the upper surface of the transfer belt 12 . The contact portion is the primary transfer portion. A primary transfer roller 16 is provided inside the transfer belt 12 so as to face the drum 4 .

A secondary transfer roller 17 is arranged at a position facing the tension roller 14 with the transfer belt 12 interposed therebetween. A contact portion between the transfer belt 12 and the secondary transfer roller 17 is a secondary transfer portion.

A feeding unit 18 is provided below the intermediate transfer belt unit 11 . The feeding unit 18 has a paper feed tray 19 and a paper feed roller 20 in which recording media S are stacked and accommodated.

A fixing unit 21 and a discharge unit 22 are provided in the upper left part of the apparatus main body 2 in FIG. A discharge tray 23 is provided on the upper surface of the apparatus main body 2 .

The recording medium S onto which the developer image has been transferred is fixed by fixing means provided in the fixing unit 21 , and then discharged to the discharge tray 23 .

The cartridge P is detachable from the apparatus main body 2 via a drawable cartridge tray 60 . 3A shows a state in which the cartridge tray 60 and the cartridge P are pulled out from the apparatus main body 2. FIG.

[Image forming operation]
The operation for forming a full-color image is as follows.

The drum 4 of each of the first to fourth cartridges P (PY, PM, PC, PK) is rotationally driven at a predetermined speed (direction of arrow D in FIG. 4, counterclockwise in FIG. 2). The transfer belt 12 is also rotationally driven at a speed corresponding to the speed of the drum 4 in the forward direction (direction of arrow C in FIG. 2) with the rotation of the drum 4 . Laser scanner unit LB is also driven. In synchronization with the driving of the scanner unit LB, the charging roller 5 uniformly charges the surface of the drum 4 to a predetermined polarity and potential. The laser scanner unit LB scans and exposes the surface of each drum 4 with a laser beam Z according to the image signal of each color. As a result, an electrostatic latent image corresponding to the image signal of the corresponding color is formed on the surface of each drum 4 . This electrostatic latent image is developed by a developing roller 6 that is rotationally driven (in the direction of arrow E in FIG. 4, clockwise in FIG. 2) at a predetermined speed. By such an electrophotographic image forming process, a yellow developer image corresponding to the yellow component of the full-color image is formed on the drum 4 of the first cartridge PY. Then, the developer image is primarily transferred onto the transfer belt 12 .

Similarly, a magenta developer image corresponding to the magenta component of the full-color image is formed on the drum 4 of the second cartridge PM. Then, the developer image is superimposed on the yellow developer image that has already been transferred onto the transfer belt 12 and is primarily transferred.

Similarly, a cyan developer image corresponding to the cyan component of the full-color image is formed on the drum 4 of the third cartridge PC. Then, the developer image is superimposed on the yellow and magenta developer images that have already been transferred onto the transfer belt 12 and is primarily transferred.

Similarly, a black developer image corresponding to the black component of the full-color image is formed on the drum 4 of the fourth cartridge PK. Then, the developer image is superimposed on the yellow, magenta, and cyan developer images that have already been transferred onto the transfer belt 12 and is primarily transferred.

In this manner, an unfixed developer image of four full colors of yellow, magenta, cyan, and black is formed on the transfer belt 12 .

On the other hand, the recording medium S is separated and fed one by one at a predetermined control timing. The recording medium S is introduced to the secondary transfer portion, which is the contact portion between the secondary transfer roller 17 and the transfer belt 12, at a predetermined control timing. As a result, the four-color superimposed developer image on the transfer belt 12 is successively transferred to the surface of the recording medium S all at once while the recording medium S is conveyed to the secondary transfer portion.

[Overall Configuration of Process Cartridge]
A configuration of a process cartridge for forming an electrophotographic image will be described. In this embodiment, the first to fourth cartridges P (PY, PM, PC, PK) have the same electrophotographic image forming process mechanism, and the color of the contained developer and the filling amount of the developer are determined. are different.

The cartridge P comprises a drum 4 and process means acting on the drum 4 . Here, the process means includes a charging roller 5 as charging means for charging the drum 4, a developing roller 6 as developing means for developing a latent image formed on the drum 4, and a residual developer remaining on the surface of the drum 4. There is a cleaning blade 7 or the like as a cleaning means for cleaning. The cartridge P is divided into a drum unit 8 and a developing unit 9 .

[Construction of drum unit]
As shown in FIGS. 4, 5, and 6, the drum unit 8 includes a drum 4 as a photoreceptor, a charging roller 5, a cleaning blade 7, a cleaning container 26 as a photoreceptor frame, a waste developer storage section 27, and a cartridge. It is composed of cover members (drive side cartridge cover member 24 and non-drive side cartridge cover member 25 in FIGS. 5 and 6). The photoreceptor frame in a broad sense includes not only the cleaning container 26, which is a photoreceptor frame in a narrow sense, but also the waste developer storage section 27, the driving side cartridge cover member 24, and the non-driving side cartridge cover member 25 ( The same applies to the following examples). Incidentally, when the cartridge P is attached to the apparatus main body 2 , the photoreceptor frame is fixed to the apparatus main body 2 .

The drum 4 is rotatably supported by cartridge cover members 24 and 25 provided at both longitudinal ends of the cartridge P. As shown in FIG. Here, the axial direction of the drum 4 is defined as the longitudinal direction.

The cartridge cover members 24 and 25 are fixed to the cleaning container 26 at both longitudinal ends of the cleaning container 26 .

As shown in FIG. 5, at one end in the longitudinal direction of the drum 4, there is provided a photoreceptor drive input portion (photoreceptor drive transmission portion) 4a, which is a coupling member for transmitting a driving force to the drum 4. is provided. FIG. 3B is a perspective view of the apparatus main body 2, in which the cartridge tray 60 and the cartridge P are not shown. The coupling members 4a of the cartridges P (PY, PM, PC, PK) are connected to drum drive output members 61 (61Y, 61M, 61C, 61K), and the driving force of the drive motor (not shown) of the apparatus main body is transmitted to the drum 4.

The charging roller 5 is supported by the cleaning container 26 so as to be in contact with the drum 4 and be rotated.

Further, the cleaning blade 7 is supported by the cleaning container 26 so as to contact the peripheral surface of the drum 4 with a predetermined pressure.

The transfer residual developer removed from the peripheral surface of the drum 4 by the cleaning means 7 is stored in the waste developer storage section 27 in the cleaning container 26 .

Further, the driving side cartridge cover member 24 and the non-driving side cartridge cover member 25 are provided with supporting portions 24a and 25a as sliding portions for rotatably supporting the developing unit 9 (see FIG. 6). ).

[Structure of development unit]
As shown in FIGS. 1 and 8, the developing unit 9 includes a developing roller 6, a developing blade 31, a developing frame 29, a bearing member 45, a developing cover member 32, and the like. Here, the developing device frame in a broad sense includes the bearing member 45, the developing device cover member 32, etc. in addition to the developing device frame 29 (the same applies to the following embodiments). It should be noted that the developing frame 29 is movable with respect to the apparatus main body 2 when the cartridge P is attached to the apparatus main body 2 .

Further, the broadly defined cartridge frame includes the above-described broadly defined photoreceptor frame and the broadly defined development frame (the same applies to the following embodiments).

The development frame 29 has a developer storage portion 49 that stores the developer to be supplied to the development roller 6 and a development blade 31 that regulates the layer thickness of the developer on the peripheral surface of the development roller 6 .

Further, as shown in FIG. 1, the bearing member 45 is fixed to one longitudinal end of the developing device frame 29 . This bearing member 45 rotatably supports the developing roller 6 . The developing roller 6 has a developing roller gear 69 as a developing roller drive transmission member at its longitudinal end. The bearing member 45 also rotatably supports a cartridge-side drive transmission member (drive input member) 74 for transmitting drive force to the developing roller gear 69 . The cartridge side drive transmission member (drive input member) 74 is configured to be capable of coupling with the development drive output member 62 (62Y, 62M, 62C, 62K) as the main body side drive transmission member of the apparatus main body 2 shown in FIG. 3(b). be done. That is, the cartridge-side drive transmission member and the development drive output member are engaged (coupled) to transmit the drive force from the drive motor (not shown) provided in the apparatus main body 2 . Details will be described later.

The developer cover member 32 is fixed outside the bearing member 45 in the longitudinal direction of the cartridge P. As shown in FIG. The developing cover member 32 is configured to cover the developing roller gear 69, a part of the cartridge-side drive transmission member 74, and the like.

[Assembling the drum unit and developing unit]
5 and 6 show how the developing unit 9 and the drum unit 8 are assembled. At one longitudinal end of the cartridge P, the outer diameter portion 32a of the cylindrical portion 32b of the developing cover member 32 is rotatably fitted to the supporting portion 24a of the driving side cartridge cover member 24. As shown in FIG. At the other longitudinal end of the cartridge P, a protrusion 29b protruding from the developing device frame 29 is rotatably fitted into the support hole 25a of the cartridge cover member 25 on the non-driving side. Thereby, the developing unit 9 is rotatably supported with respect to the drum unit 8 . Here, the axis of rotation that serves as the center of rotation of the developing unit 9 with respect to the drum unit is referred to as the axis of rotation X. As shown in FIG. The center of rotation X is an axis connecting the center of the opening 24e provided in the support 24a and the center of the support hole 25a.

[Contact between developing roller and drum]
As shown in FIGS. 4, 5, and 6, the developing unit 9 is biased by a pressure spring 95, which is an elastic member as a biasing member, so that the developing roller 6 rotates around the rotation axis X as a drum. 4 is configured to contact. That is, the developing unit 9 is pressed in the direction of arrow G in FIG.

As a result, the developing roller 6 can be brought into contact with the drum 4 with a predetermined pressure. The position of the developing unit 9 with respect to the drum unit 8 at this time is defined as the contact position. Further, the developing roller 6 can be separated from the drum 4 by moving the developing unit 9 in the direction opposite to the direction of the arrow G against the biasing force of the pressure spring 95 . That is, the developing roller 6 is constructed so as to be able to come into contact with and separate from the drum 4 .

[Separation between developing roller and drum]
FIG. 7 is a schematic side view of the cartridge P viewed from the driving side along the axis of rotation of the developing roller. In this figure, some parts are not shown for the sake of explanation. The drum unit 8 is positioned in the apparatus main body 2 when the cartridge P is attached to the apparatus main body 2 .

In this embodiment, the bearing member 45 is provided with an urging force receiving portion (spacing force receiving portion) 45a. Incidentally, the biasing force receiving portion (separation force receiving portion) 45a is not limited to the bearing member 45, and may be provided at any part of the cartridge P (for example, the developing frame or the like). The biasing force receiving portion (spacing force receiving portion) 45 a is configured to be engageable with a separation force biasing member (main body side biasing member) 80 as a main body side biasing member provided in the apparatus main body 2 . . A separation force urging member (main body side urging member) 80 as the main body side urging member receives a driving force from a motor (not shown) and is configured to be movable in the directions of arrows F1 and F2 along rails 81. It's becoming

The operation of separating the developing roller and the photoreceptor (drum) will be described below.

FIG. 7(a) shows a state in which the drum 4 and the developing roller 6 are in contact with each other. At this time, the biasing force receiving portion (separation force receiving portion) 45a and the separation force biasing member (main body side biasing member) 80 are separated from each other with a gap d.

FIG. 7(b) shows a state in which the separating force biasing member (main body side biasing member) 80 has moved in the direction of arrow F1 by a distance δ1 with reference to the state of FIG. 7(a). At this time, the biasing force receiving portion (separation force receiving portion) 45 a is engaged with the separation force biasing member (main body side biasing member) 80 . As described above, the developing unit 9 is rotatable with respect to the drum unit 8, and in FIG. It is in a rotated state. At this time, the drum 4 and the developing roller 6 are separated from each other by a distance ε1.

FIG. 7(c) shows a state in which the separation force biasing member (main body side biasing member) 80 has moved by δ2 (>δ1) in the direction of arrow F1 with reference to the state of FIG. 7(a). The developing unit 9 is rotated about the rotation axis X in the direction of the arrow K by an angle θ2. At this time, the drum 4 and the developing roller 6 are separated from each other by a distance ε2.

[Arrangement Relationship Between Developing Roller, Cartridge Side Drive Transmission Member, and Biasing Force Receiving Portion]
As shown in FIGS. 7A to 7C, when the cartridge P is viewed from the driving side along the rotation axis of the developing roller, the developing roller 6 is formed between the cartridge-side drive transmission member 74 and the biasing force receiving portion 45a. placed in between. That is, when the cartridge P is viewed along the rotation axis of the developing roller, the biasing force receiving portion (spacing force receiving portion) 45a is positioned substantially opposite to the drive input member 74 with respect to the developing roller 6. Protruding. Specifically, a line connecting the contact portion 45b of the biasing force receiving portion 45a that receives the force from the body-side biasing member 80 and the rotation axis 6z of the developing roller 6, the rotation axis 6z of the developing roller 6, and the cartridge side drive A line connecting the rotation axis of the transmission member 74 (coaxial with the rotation axis X in this embodiment) intersects at an angle and is not on the same straight line. Also, when the cartridge P is viewed along the rotation axis of the developing roller, a line connecting the contact portion 45b and the rotation axis of the cartridge-side drive transmission member 74 is arranged so as to pass through the developing roller 6. there is Including such a form, it is expressed that the developing roller 6 is disposed between the cartridge-side drive transmission member 74 and the biasing force receiving portion 45a. In this embodiment, the rotation axis X of the developing unit 9 with respect to the drum unit is coaxial with the rotation axis of the cartridge-side drive transmission member 74 .

Further, the rotation axis 6z of the developing roller 6 is arranged between the rotation axis 4z of the photosensitive member 4, the rotation axis (X) of the cartridge-side drive transmission member 74, and the contact portion 45b of the biasing force receiving portion 45a. be done. That is, when the cartridge P is viewed from the drive side along the rotation axis of the developing roller, the rotation axis 4z of the photosensitive member 4, the rotation axis X of the cartridge-side drive transmission member 74, and the contact portion 45b are connected. A rotation axis 6z of the developing roller 6 is arranged in a triangle surrounded by three straight lines.

Here, since the developing unit 9 rotates with respect to the drum unit 8, the positional relationship of the cartridge-side drive transmission member 74 and the biasing force receiving portion 45a with respect to the photosensitive member 4 changes. However, in either case, the rotation axis 6z of the developing roller 6 is arranged between the rotation axis 4z, the rotation axis (X) of the cartridge-side drive transmission member 74, and the contact portion 45b.

By arranging the developing roller between the contact portion 45b and the rotation axis X in this way, compared to a configuration in which the development roller is separated from the contact portion 45b and the rotation axis X, There is an effect that the separation and contact of the developing roller can be performed with high accuracy. Furthermore, when viewing the cartridge P along the rotation axis of the developing roller from the driving side, the distance between the rotation axis X and the rotation axis 6z of the developing roller 6 is calculated as follows: The longer the distance, the more precisely the separation/contact timing of the developing roller can be controlled.

In this embodiment (the same applies to the following embodiments), the distance between the portion where the biasing force receiving portion (separation force receiving portion) 45a abuts against the body side biasing member 80 and the rotation axis of the drum 4 is It ranges from 13 mm to 33 mm. Further, in this embodiment (the same applies to the following embodiments), the distance between the portion of the force receiving portion 45a that abuts on the body-side biasing member 80 and the rotation axis X is in the range of 27 mm to 32 mm. .

[Drive transmission to photosensitive drum]
Next, an outline of drive transmission to the photosensitive drum 4 will be described.

As described above, the photoreceptor drive input portion (photoreceptor drive transmission portion) 4a, which is a coupling member provided at the end of the drum 4 as a photoreceptor, is provided in the apparatus main body 2 shown in FIG. It engages with the drum driving output members 61 (61Y, 61M, 61C, 61K) and receives the driving force of the driving motor (not shown) of the apparatus main body. As a result, the drive from the apparatus body is transmitted to the drum 4 .

As shown in FIG. 1, from the opening 24d of the drive-side cartridge cover member 24, which is a frame provided at the longitudinal end of the cartridge P, the coupling member provided at the end of the photosensitive drum 4 is accessed. is exposed (photoreceptor drive transmission portion) 4a. More specifically, the photoreceptor drive input portion 4a is arranged to protrude toward the outside of the cartridge from the opening surface of the driving side cartridge cover member 24 where the opening portion 24d is provided. Here, the photoreceptor drive input portion 4a is fixed in the direction toward the inside of the cartridge P (the direction along the rotation axis of the photoreceptor), unlike the drive input portion 74b that is movable forward and backward. . That is, the photoreceptor drive input portion 4a is fixed to the drum 4. As shown in FIG.

[Drive transmission to developing roller]
(Drive connection and principle of release mechanism)
The configuration of the drive connecting portion will be described with reference to FIGS. 1 and 8. FIG. Here, the drive connection portion is a mechanism that receives drive from the development drive output member 62 as a main body drive transmission member of the apparatus main body 2 and transmits and interrupts the drive to the development roller 6 . The drive connecting portion of this embodiment is composed of the spring 70 , the drive input member 74 , the release cam 72 , the developing cover member 32 , and the driving side cartridge cover member 24 .

As shown in FIGS. 1 and 8, the cartridge-side drive transmission member 74 and the development drive output member 62 are engaged through the opening 24e, the opening 32d, and the opening 72f of the release cam 72. there is Specifically, as shown in FIG. 1, openings 24e and 24d, which are through-holes, are provided in a drive-side cartridge cover member 24, which is a frame provided at the longitudinal end of the cartridge. The developing cover member 32 combined with the driving side cartridge cover member 24 has a cylindrical portion 32b, and the cylindrical portion 32b is provided with an opening 32d as a through hole.

The cartridge-side drive transmission member 74 has a shaft-shaped shaft portion 74x, and a drive input portion 74b as a rotational force receiving portion is provided at the end portion of the shaft portion 74x. The shaft portion 74x is combined so as to pass through the opening 72f of the release cam, the opening 32d of the developer cover member 32, and the opening 24e of the driving side cartridge cover member 24, and the drive input portion 74b at the tip extends toward the outside of the cartridge. exposed. Specifically, the drive input portion 74b is arranged to protrude toward the outside of the cartridge from the opening surface of the driving side cartridge cover member 24 provided with the opening portion 24e. By coupling the convex portion of the drive input portion 74b with the concave portion 62b provided in the main body side drive transmission member 62, the drive from the main body side is transmitted to the drive input portion 74b. The drive input portion 74b has a shape in which a substantially triangular prism is slightly twisted (see FIG. 1).

Further, a gear portion 74g provided on the outer peripheral surface of the cartridge-side drive transmission member 74 engages with the developing roller gear 69. As shown in FIG. As a result, the drive transmitted to the drive input portion 74b of the cartridge-side drive transmission member 74 is transmitted to the developing roller 6 via the gear portion 74g of the cartridge-side drive transmission member 74 and the developing roller gear 69. FIG.

The drive input portion 74b of this embodiment is configured to be movable in the direction toward the inside of the cartridge. More specifically, the release cam 72 presses the urged portion 74c provided at the base of the shaft portion 74x of the cartridge-side drive transmission member 74, so that the drive input member 74 retreats toward the inside of the cartridge. As a result, it becomes possible to transmit and block the drive input from the main body side drive transmission member 62 .

In this embodiment and the following embodiments, the direction toward the inside of the cartridge is the direction along the rotation axis X, which is the direction N in FIG. However, even if the direction is slightly inclined with respect to the rotation axis X, as long as the direction in which the coupling between the drive input portion 74b and the main body side drive transmission member 62 is released, that direction is also directed toward the inside of the cartridge. Define direction.

(Structure of drive connecting portion)
A more detailed configuration will be described with reference to FIGS. 1, 8, and 9. FIG. Between the driving side cartridge cover member 24 arranged as a part of the frame at the longitudinal end of the cartridge P and the bearing member 45 with which the shaft of the developing roller is engaged, there is provided a driving side from the bearing member 45 Toward the cartridge cover member 24, a spring 70 which is an elastic portion as a biasing member, a drive input member 74 as a cartridge side drive transmission member biased by the spring 70, and a coupling release member which is a part of the release mechanism. A release cam 72 and a developing cover member 32 are provided as a release cam 72 . The rotation axes of these members are coaxial with the rotation axis of the drive input member 74, that is, are located on the same straight line. The same straight line (coaxial line) mentioned above is the same within the range of dimensional tolerance of each part, and the same applies to the following embodiments.

FIG. 9 shows a schematic cross-sectional view of the drive connecting portion.

As described above, the bearing portion 74p (cylindrical inner surface) of the drive input member 74 and the first bearing portion 45p (cylindrical outer surface) of the bearing member 45 are engaged with each other. Further, the cylindrical portion 74q of the drive input member 74 and the inner diameter portion 32q of the developing device cover member 32 are engaged with each other. That is, the driving input member 74 is rotatably supported at both ends by the bearing member 45 and the developing device cover member 32 .

Furthermore, the bearing member 45 rotatably supports the developing roller 6 . More specifically, the second bearing portion 45q (cylindrical inner surface) of the bearing member 45 rotatably supports the shaft portion 6a of the developing roller 6. As shown in FIG. A developing roller gear 69 is fitted to the shaft portion 6 a of the developing roller 6 . As described above, the outer peripheral surface of the drive input member 74 is a gear portion 74g that meshes with the developing roller gear 69. As shown in FIG. As a result, the rotational force is transmitted from the drive input member 74 to the developing roller 6 via the developing roller gear 69 .

Further, the centers of the first bearing portion 45p (outer cylindrical surface) of the bearing member 45 and the inner diameter portion 32q of the developing device cover member 32 are arranged on the same straight line as the rotation axis X of the developing unit 9. As shown in FIG. That is, the drive input member 74 is rotatably supported around the rotation axis X of the developing unit 9 .

Further, a drive-side cartridge cover member 24 is provided outside the developer cover member 32 in the longitudinal direction of the cartridge P. As shown in FIG. FIG. 9A is a schematic cross-sectional view showing a coupling state between the drive input portion 74b of the drive input member 74 and the development drive output member 62 of the apparatus main body. In this manner, the drive input portion 74b protrudes toward the outside of the cartridge with respect to the opening surface of the drive side cartridge cover member 24 provided with the opening 24e, and the rotational driving force from the development drive output member 62 is applied to the drive input portion. A first position of the drive input member 74 is a state in which the drive input member 74 can be transmitted to the drive input member 74b. A spring 70, which is an elastic member as a biasing member, is provided between the bearing member 45 and the drive input portion 74b so as to press the drive input portion 74b in the arrow M direction.

9A, when the release cam 72 and the drive input member 74 are projected onto an imaginary line parallel to the rotation axis of the developing roller 6, the area of the release cam 72 is the cartridge-side drive transmission member 74. located within the area of By forming at least a partial area of the release cam 72 and a partial area of the drive input member 74 to overlap each other, the size of the drive release mechanism can be reduced.

FIG. 9(b) is a schematic cross-sectional view showing a state in which the drive input portion 74b and the development drive output member 62 are separated from each other. The drive input portion 74b is configured to be movable in the arrow N direction against the pressing force of the spring 39 by being pressed by the release cam 72, which is an urging mechanism.

As shown in FIG. 9B, the position where the rotational driving force from the development drive output member 62 is not transmitted to the drive input portion 74b is defined as the second position of the drive input member 74. As shown in FIG. The second position is a position where the drive input portion 74b has moved toward the inside of the cartridge with respect to the first position. At the second position, it is desirable that the drive input portion 74b at the end of the cartridge drive input member is recessed with respect to the outer surface of the cartridge on which the opening surface of the frame is formed. However, as shown in FIG. 9B, the outer surface and the end surface of the drive input portion 74b may be substantially on the same surface, or the end surface of the drive input portion 74b may be slightly convex from the outer surface. It may be In either case, as long as the drive input portion 74 moves toward the inside of the cartridge from the first position and the coupling between the development drive output member 62 and the drive input member 74 is released. , is defined as the second position.

12 shows a cross-sectional view of the parts configuration of the bearing member 45, the spring 70, the drive input member 74, and the developing roller gear 69. As shown in FIG.

A first bearing portion 45p (cylindrical outer surface) as a first guide portion of the bearing member 45 rotatably supports a bearing portion 74p (cylindrical inner surface) as a first guided portion of the drive input member 74 . The drive input member 74 is movable along the rotation axis (rotation center) X in a state where the bearing portion 74p (cylindrical inner surface) is engaged with the first bearing portion 45p (cylindrical outer surface). In other words, the bearing member 45 holds the drive input member 74 along the rotation axis X so as to be slidable (reciprocable). Further in other words, the drive input member 74 is slidable in the arrow M or N direction with respect to the bearing member 45 .

12(b) shows a state in which the drive input member 74 has moved in the arrow N direction with respect to the bearing member 45 with reference to the state of FIG. 12(a). The drive input member 74 is configured to be movable in the arrow M and N directions while meshing with the developing roller gear 69 . In order to facilitate the movement of the drive input member 74 along the rotation axis X in the direction of arrow M (direction toward the outside of the cartridge) and the direction of N (direction toward the inside of the cartridge), the gear portion of the drive input member 74 is provided. 74g is preferably a spur gear rather than a helical gear. The position of the drive input member 74 in FIG. 12(a) corresponds to the first position described above, and the position of the drive input member 74 in FIG. 12(b) corresponds to the second position described above.

(Release mechanism)
Next, the drive release mechanism will be described.

As shown in FIGS. 1 and 8, between the gear portion 74g of the drive input member 74 and the developing device cover member 32, a release cam 72 is provided as a part of the release mechanism and as a coupling release member. . In other words, the release cam 72 is provided within the range of the drive input member 74 in the direction parallel to the rotation axis of the developing roller 6 .

10 shows the relationship between the release cam 72 and the developing cover member 32. As shown in FIG. The release cam 72 is provided with a substantially ring-shaped ring portion, and further has an outer peripheral portion which is an outer peripheral surface. A protruding portion 72i protruding from the ring portion is provided on the outer peripheral portion. In this embodiment, the protrusion 72i protrudes in the direction along the rotation axis of the developing roller. Further, the developing device cover member 32 has an inner peripheral surface 32i. The inner peripheral surface 32i is configured to engage with the outer peripheral surface. As a result, the release cam 72 is slidably supported on the developing cover member 32 (slidable along the axis of the developing roller 6). In other words, the release cam 72 can move substantially parallel to the rotation axis of the developing roller 6 with respect to the developing cover member 32 . Here, the centers of the outer peripheral surface of the release cam 72, the inner peripheral surface 32i of the developer cover member 32, and the outer diameter portion 32a of the developer cover member 32 are coaxially provided.

Further, a pressing surface 72c as a biasing portion is provided on the surface opposite to the direction in which the projecting portion 72i of the release cam 72 projects. The pressing surface 72c presses (biases) a pressed surface 74c of the drive input member 74, as will be described later.

The developing cover member 32 has a guide 32h as a second guide portion, and the release cam 72 has a guide groove 72h as a second guided portion. Both the guide 32h and the guide groove 72h are formed parallel to the axial direction. Here, the guide 32h of the developing cover member 32 engages with the guide groove 72h of the releasing cam 72 as the coupling releasing member. Since the guide 32h and the guide groove 72h are engaged with each other, the release cam 72 is slidable only in the axial direction (directions of arrows M and N) with respect to the developing cover member 32. there is

Both sides of the guide 32h and the guide groove 72 do not need to be parallel to the rotation axis X, and it is sufficient that only one side in contact with each other is formed parallel to the rotation axis X.

FIG. 11 shows the configuration of the release cam 72, the developer cover member 32, and the driving side cartridge cover member 24. As shown in FIG.

A drive-side cartridge cover member 24 is provided outside the developer cover member 32 in the longitudinal direction of the cartridge P. As shown in FIG.

The release cam 72 as a coupling release member has a contact portion (inclined surface) 72a as a force receiving portion that receives force generated by the device main body 2 (main body side biasing member 80). Further, the drive-side cartridge cover member 24 has a contact portion (inclined surface) 24b as an action member. Further, the developing device cover member 32 has another opening 32j around the opening 32d. The contact portion 72a of the release cam 72 and the contact portion 24b of the drive-side cartridge cover member 24 are configured to contact each other through the other opening 32j of the developer cover member 32. As shown in FIG.

In the above description, there are two contact portions 72a of the release cam 72 and two contact portions 24b of the drive-side cartridge cover member 24, but the number is not limited to this. For example, the number of contact portions may be three.

The number of contact portions may be one, but in that case, the force acting on the contact portions during drive transmission/release operation (details will be described later) causes the release cam 72 to move with respect to the axis X. There is a risk that the axis will fall over. There is concern that the drive switching performance, such as the timing of the drive connection/disengagement operation, may be deteriorated due to the occurrence of the shaft tilt. In order to suppress the axial inclination, it is possible to reinforce the supporting portion (the inner peripheral surface 32i of the developer cover member 32) that slidably supports the release cam 72 (slidable along the axis of the developing roller 6). desirable. On the other hand, it is desirable that the number of contact portions is plural and that they are arranged at substantially equal intervals in the circumferential direction with the axis X as the center. In this case, the resultant force acting on the contact portion acts as a moment to rotate the release cam 72 around the axis X. As shown in FIG. Therefore, the tilting of the release cam 72 with respect to the axis X can be suppressed. Furthermore, when three or more abutting portions are provided, it is possible to define a plane supporting the release cam 72 with respect to the axis X, thereby further suppressing axial inclination of the release cam 72 with respect to the axis X. . That is, the posture of the release cam 72 can be stabilized.

[Drive release operation]
The operation of the drive connecting portion when the developing roller 6 and the drum 4 change from being in contact with each other to being separated from each other will be described below with reference to FIGS. 7 and 13 to 15. FIG. 13 to 15, some parts are not shown for the sake of explanation, and a part of the structure of the release cam is schematically shown. In this embodiment, the arrow M along the rotation axis X in the drawing indicates the direction toward the outside of the cartridge, and the arrow M along the rotation axis X indicates the direction toward the inside of the cartridge.

[State 1]
As shown in FIG. 7A, the separation force biasing member 80 and the biasing force receiving portion (separation force receiving portion) 45a of the bearing member 45 are separated from each other with a gap d. At this time, the drum 4 and the developing roller 6 are in contact with each other. This state is referred to as state 1 of the separating force urging member 80 . FIG. 13 shows the configuration of the drive connecting portion at this time. In FIG. 13A, the pair of drive input member 74 and development drive output member 62 and the pair of release cam 72 and drive side cartridge cover member 24 are schematically shown separately. FIG. 13(b) shows a perspective view of the configuration of the drive connecting portion. In FIG. 13B, only a portion of the driving side cartridge cover member 24 including the contact portion 24b is shown, and only a portion of the developing device cover member 32 including the guide 32h is shown. Between the contact portion 72a of the release cam 72 and the contact portion 24b of the driving side cartridge cover member 24, there is a gap e. Further, at this time, the drive input member 74 and the development drive output member 62 are engaged with each other with an engagement amount q, so that drive transmission is possible. Further, as described above, the drive input member 74 is engaged with the developing roller gear 69 (see FIG. 12). Therefore, the driving force input from the apparatus main body 2 to the driving input member 74 is transmitted to the developing roller gear 69, and the developing roller 6 is driven. The above state of each part is called a contact position, and is called a development contact/drive transmission state. Further, the position of the drive input member 74 at this time is defined as the first position.

[State 2]
As shown in FIG. 7B, when the separation force biasing member (main body side biasing member) 80 is moved by δ1 in the direction of the arrow F1 in the drawing from the development contact/drive transmission state, as described above, the development occurs. The unit 9 rotates about the rotation axis X in the direction of the arrow K by an angle θ1. As a result, the developing roller 6 is separated from the drum 4 by a distance ε1. The releasing cam 72 and the developing cover member 32 incorporated in the developing unit 9 rotate in the direction of the arrow K by an angle θ1 in conjunction with the rotation of the developing unit 9 . On the other hand, when the cartridge P is attached to the apparatus main body 2 , the drum unit 8 , driving side cartridge cover member 24 and non-driving side cartridge cover member 25 are positioned and fixed to the apparatus main body 2 . That is, as shown in FIGS. 14A and 14B, the contact portion 24b of the driving side cartridge cover member 24 does not move. In the figure, the release cam 72 rotates in the direction of the arrow K in conjunction with the rotation of the developing unit 9, and the contact portion 72a of the release cam 72 and the contact portion 24b of the driving side cartridge cover member 24 contact each other. are starting to come into contact with each other. At this time, the drive input member 74 and the development drive output member 62 are kept engaged with each other (FIG. 14(a)). Therefore, the driving force input from the apparatus main body 2 to the drive input member 74 is transmitted to the developing roller 6 via the developing roller gear 69 . The above-described state of each component is referred to as the development separation/drive transmission state. The position of the drive input member 74 at this time is also the first position.

[State 3]
As shown in FIG. 7(c), when the separation force urging member (main body side urging member) 80 moves in the direction of the arrow F1 in the figure by δ2 from the development separation/drive transmission state, the drive connection portion The configuration is shown in FIGS. 15(a) and 15(b). The releasing cam 72 and the developing cover member 32 rotate in conjunction with the rotation of the developing unit 9 at an angle θ2 (>θ1). On the other hand, the drive-side cartridge cover member 24 does not change its position as described above, and the release cam 72 rotates in the arrow K direction in the figure. At this time, the contact portion 72 a of the release cam 72 receives a reaction force from the contact portion 24 b of the driving side cartridge cover member 24 . Further, as described above, the guide groove 72h of the release cam 72 is engaged with the guide 32h of the developing device cover member 32 so that the release cam 72 is restricted to move only in the axial direction (directions of arrows M and N) ( See Figure 10). As a result, the release cam 72 slides in the direction of the arrow N by the movement amount p with respect to the developing cover member. In conjunction with the movement of the release cam 72 in the direction of the arrow N, the pressing surface 72c, which is the biasing portion of the release cam 72 as a biasing member, presses (biases) the pressed surface 74c of the drive input member 74. do. As a result, the drive input member 74 slides in the direction of the arrow N by the movement amount p against the pressing force of the spring 70 (see FIGS. 15 and 12(b)).

At this time, since the movement amount p is larger than the engagement amount q between the drive input member 74 and the development drive output member 62, the engagement between the drive input member 74 and the development drive output member 62 is released. Along with this, the development drive output member 62 of the apparatus main body 2 continues to rotate, while the drive input member 74 stops. As a result, the developing roller gear 69 and the developing roller 6 stop rotating. The above-described state of each part is called a separated position, and is also called a developing separation/drive cutoff state. The position of the drive input member 74 at this time is defined as a second position.

In this way, the drive input member 74 is pushed by the biasing portion 72c of the release cam 72, and the drive input member 74 moves from the first position to the second position toward the inside of the cartridge. As a result, the engagement between the drive input member 74 and the development drive output member 62 is released, and the rotational force from the development drive output member 62 is no longer transmitted to the drive input member 74 .

The movement distance p by which the drive input member 74 moves from the first position to the second position is equal to or greater than the engagement amount q between the drive input member 74 and the development drive output member 62 (see FIG. 34), and more preferably It is equal to or greater than the height 74z (the length in the direction of the axis X) of the drive input portion 74b (see FIG. 12). Specifically, the moving distance p in this embodiment is 2.2 mm. In order to reliably transmit and release the driving force from the main body side, the moving distance p is preferably in the range of 2 mm or more and 3 mm or less.

The operation of shutting off the driving of the developing roller 6 in conjunction with the rotation of the developing unit 9 in the direction of the arrow K has been described above. By adopting the above configuration, the developing roller 6 can be separated from the drum 4 while rotating. As a result, the drive to the developing roller 6 can be interrupted according to the separation distance between the developing roller 6 and the drum 4 .

[Drive connection operation]
Next, the operation of the drive connecting portion when the developing roller 6 and the drum 4 change from the separated state to the contact state will be described. This operation is the reverse of the operation from the development contact state to the development separation state described above.

In the development separation state (the development unit 9 is rotated by an angle θ2 as shown in FIG. 7(c)), the drive connection portion is connected to the drive input member 74 and the development drive output member 62 as shown in FIG. is disengaged. That is, the drive input member 74 is in the second position.

From the above state, the developing unit 9 is gradually rotated in the direction of arrow H shown in FIG. , and the state shown in FIG. 14), the drive input member 74 is moved in the direction of arrow M by the pressing force of the spring 70, so that the drive input member 74 and the development drive output member 62 are engaged with each other.
As a result, the driving force from the apparatus main body 2 is transmitted to the developing roller 6, and the developing roller 6 is rotationally driven. That is, the drive input member 74 is in the first position. At this time, the developing roller 6 and the drum 4 are kept separated from each other.

Further, by gradually rotating the developing unit 9 in the direction of arrow H shown in FIG. 7 from the above state, the developing roller 6 and the drum 4 can be brought into contact with each other. Even in this state, the drive input member 74 is at the first position.

The operation of transmitting the driving force to the developing roller 6 in conjunction with the rotation of the developing unit 9 in the direction of the arrow H has been described above. With the above configuration, the developing roller 6 contacts the drum 4 while rotating, and the drive can be transmitted to the developing roller 6 according to the distance between the developing roller 6 and the drum 4 .

As described above, in this configuration, it is possible to uniquely determine the switching between the cutoff and transmission of drive to the developing roller 6 by the angle at which the developing unit 9 rotates.

In the above description, the contact portion 72a of the release cam 72 and the contact portion 24b of the drive-side cartridge cover member 24 are in face-to-face contact with each other, but this is not necessarily the case. For example, a configuration in which a surface and an edge line, a surface and a point, an edge line and an edge line, or an edge line and a point are in contact with each other may be employed.

[Release Mechanism]
Next, the mechanism of the release mechanism will be described with reference to the schematic diagram of FIG.

16(a) shows the development contact/drive transmission state, FIG. 16(b) the development separation/drive transmission state, and FIG. 16(c) the development separation/drive cutoff state. . These are the same states as shown in FIGS. 13, 14 and 15, respectively. In FIG. 16C, the release cam 72 and the driving side cartridge cover member 24 are in contact with each other at the contact portion 72a and the contact portion 24b that are inclined with respect to the rotation axis X. As shown in FIG. Here, in the development separation/driving cutoff state, the release cam 72 and the driving side cartridge cover member 24 may have the positional relationship shown in FIG. 16(d). That is, as shown in FIG. 16C, after the abutting portion 72a and the abutting portion 24b, which are inclined with respect to the rotation axis X, are in contact with each other, the developing unit 9 is further rotated. As a result, the release cam 72 and the drive-side cartridge cover member 24 are brought into contact with each other at the plane portions 72s and 24s perpendicular to the rotation axis X, respectively.

Here, when there is a gap f between the guide groove 72h of the release cam 72 and the guide 32h of the developing device cover member 32 as shown in FIG. The transition from the state to the development separation/drive cutoff state shown in FIG. 16(d) is the same as before. On the other hand, in the transition from the development separation/drive cut-off state shown in FIG. 16(d) to the drive connection state shown in FIG. There is no gap f between and (FIG. 16(e)). Next, the contact portion 72a and the contact portion 24b transition to the state immediately before contact (FIG. 16(f)). Next, the contact portion 72a and the contact portion 24b are in contact with each other (FIG. 16(c)). After that, the relative positional relationship between the release cam 72 and the driving side cartridge cover member 24 in the process of transitioning the developing unit 9 from the development separated state to the development contact state is the same as described above.

When there is a gap f between the guide groove 72h of the release cam 72 and the guide 32h of the developing cover member 32 as shown in FIG. The release cam 72 does not move in the arrow M direction until the By moving the release cam 72 in the direction of the arrow M, the driving connection between the drive input member 74 and the development drive output member 62 is performed. In other words, the timing of movement of the release cam 72 in the direction of arrow M and the timing of driving connection are synchronized. That is, the timing of drive connection can be controlled by the gap f between the guide groove 72h of the release cam 72 and the guide 32h of the developer cover member 32. FIG.

On the other hand, in the states shown in FIGS. 15 and 16(c), the configuration in which the development unit 9 is separated from the development and the drive is cut off will be described. That is, the state in which the release cam 72 and the driving side cartridge cover member 24 are in contact with each other at the abutment portions 72a and 24b that are inclined with respect to the rotation axis X is called the development separated/drive cutoff state. do. In that case, the timing at which the release cam 72 moves in the direction of arrow M does not depend on the gap f between the guide groove 72h of the release cam 72 and the guide 32h of the developing cover member 32 . That is, the timing of drive connection can be controlled with higher precision. Further, the amount of movement of the release cam 72 in the directions of the arrows M and N can be reduced, and the size of the process cartridge in the axial direction can be reduced.

[Difference from conventional example]
Here, differences from the conventional configuration will be described below.

In Japanese Patent Application Laid-Open No. 2002-100001, a coupling that receives a drive from the image forming apparatus main body and a spring clutch that switches the drive are provided at the end of the developing roller. Further, a link interlocking with the rotation of the developing unit is provided inside the process cartridge. When the developing unit rotates and the developing roller separates from the drum, the link acts on a spring clutch provided at the end of the developing roller to cut off the drive to the developing roller.

Variation exists in the spring clutch itself. That is, the configuration is such that a time lag is likely to occur between the actuation of the spring clutch and the actual release of drive transmission. Furthermore, due to variations in dimensions of the link mechanism and variations in the angle of rotation of the developing unit, variations in the timing at which the link mechanism acts on the spring clutch occur. Further, the link mechanism that acts on the spring clutch is provided at a portion of the developing unit and drum unit that is not the center of rotation.

On the other hand, in the present embodiment, the configuration for switching the drive transmission to the developing roller (the contact portion 72a of the release cam 72, the contact portion 24b acting on the contact portion 24b acting on the drive side cartridge cover member 24, the release cam 72 and the contact portion (sloped surface) 24b of the drive-side cartridge cover member 24, variation in control of the rotation time of the developing roller can be reduced.

Further, the structure of these clutches is arranged on the same straight line as the rotation center at which the developing unit is rotatably supported with respect to the drum unit. Here, the center of rotation has the smallest relative positional error between the drum unit and the developing unit. Therefore, by arranging the clutch for switching the drive transmission to the developing roller at the rotation center, it is possible to control the switching timing of the clutch with respect to the rotation angle of the developing unit with the highest accuracy. As a result, the rotation time of the developing roller can be controlled with high precision, and deterioration of the developing roller and the developer can be suppressed.

Further, in some conventional image forming apparatuses and process cartridges, the image forming apparatus is provided with a clutch for switching driving to the developing roller.

For example, when performing monochrome printing in a full-color image forming apparatus, a clutch is used to cut off drive to a developing device containing a developer of a color other than black. Also in a monochrome image forming apparatus, when the electrostatic latent image on the drum is developed by the developing device, the driving is transmitted to the developing device, and when the developing device is not developed, the driving to the developing device is cut off. You can also operate the clutch like this. It is possible to suppress the deterioration of the developing roller and the developer by cutting off the drive to the developing device when the image is not formed and suppressing the rotation time of the developing roller.

By providing the clutch in the process cartridge, the size of the clutch can be reduced as compared with the case where the image forming apparatus is provided with a clutch for switching the drive to the developing roller. FIG. 17 is a block diagram showing an example of the gear arrangement of the image forming apparatus when the drive from the motor (driving source) provided in the image forming apparatus is transmitted to the process cartridge. Drive is transmitted from the motor 83 to the process cartridge P(PK) via an idler gear 84(K), a clutch 85(K) and an idler gear 86(K). Further, when the drive is transmitted from the motor 83 to the process cartridges P (PY, PM, PC), it is performed via an idler gear 84 (YMC), a clutch 85 (YMC), and an idler gear 86 (YMC). The drive of motor 83 is branched to idler gear 84 (K) and idler gear 84 (YMC), and the drive from clutch 85 (YMC) is branched to idler gear 86 (Y), idler gear 86 (M), and idler gear 86 (C). ).

For example, when performing monochrome printing with a full-color image forming apparatus, the clutch 85 (YMC) is used to cut off the drive to the developing device containing developer of colors other than black. When performing full-color printing, the drive of the motor 83 is transmitted to each process cartridge P via the clutch 85 (YMC). At this time, the load for driving each process cartridge P concentrates on the aforementioned clutch 85 (YMC). In particular, a load that is three times the load applied to the clutch 85 (K) concentrates on the clutch 85 (YMC). Also, load fluctuations of each color developing device similarly act on one clutch 85 (YMC). Even if a concentrated load or a load fluctuation occurs, it is necessary to increase the rigidity of the clutch in order to transmit the drive without degrading the rotational accuracy of the developing roller. Therefore, there are cases where the clutch is made larger or made of a highly rigid material such as sintered metal. On the other hand, when each process cartridge is provided with a clutch, the load and load fluctuation acting on each clutch are only the load and load fluctuation of each developing device. Therefore, compared with the previous example, there is no need to increase the rigidity, and each clutch can be made smaller.

Furthermore, in the gear arrangement for transmitting drive to the black process cartridge P (PK) shown in FIG. 17, it is desirable to reduce the load applied to the clutch 85 (K) for switching drive as much as possible. In the gear arrangement for driving and transmitting the process cartridge P, considering the driving transmission efficiency of the gears, the closer to the process cartridge P, which is the driven body, the lower the load acting on each gear shaft. Therefore, the size of the clutch can be reduced by arranging the clutch between the cartridge and the apparatus main body, that is, in the cartridge, rather than arranging the clutch for switching the drive in the image forming apparatus main body.

[Example 2]
Next, a cartridge according to a second embodiment of the invention will be described. The description of the configuration similar to that of the first embodiment is omitted. A feature of this embodiment is that a universal joint (Oldham's coupling) is provided inside the cartridge so that the rotational axis X of the developing unit 9 with respect to the drum unit 8 and the rotational axis Z of the drive input member 274 are different. In the following embodiments, an example in which the rotation axis X is parallel to the rotation axis Z will be described.

The engagement relationship between the drive input member 274 and the development drive output member 62 of the apparatus main body in this embodiment is the engagement relationship between the drive input portion 74b of the drive input member 74 and the development drive output member 62 of the apparatus main body in the first embodiment. is equivalent to

Specifically, the cartridge-side drive transmission member 274 penetrates the opening 272f, the opening 232d, and the opening 224e of the release cam 272 and protrudes toward the outside of the cartridge. When the cartridge-side drive transmission member 274 is engaged with the development drive output member 62, the drive force (rotational force) for rotating the development roller is received from the apparatus main body.

Furthermore, the engagement relationship between the release cam 272 and the developing cover member 232, and the engagement relationship between the release cam 272, the developing cover member 232, and the drive side cartridge cover member 224 are also the same as those of the first embodiment (FIGS. See Figure 11).

Further, the structure of the photoreceptor drive input portion (photoreceptor drive transmission portion) 4a that receives the driving force for rotating the photoreceptor drum 4 is also the same as that of the first embodiment. Specifically, the photoreceptor drive input portion 4a protrudes through the opening 224d. By engaging the drum drive output member 61 (see FIG. 3), the photoreceptor drive input portion 4a receives the drive force (rotational force) from the apparatus main body.

[Construction of Drive Connection Part]
18 and 19, the configuration of the drive connecting portion of this embodiment will be described. The drive connecting portion in this embodiment includes a spring 70, an idler gear 271 as an Oldham coupling downstream member, an Oldham coupling intermediate body 42, a drive input member 274 as an Oldham coupling upstream member, and a part of a release mechanism. It is composed of a release cam 272, a developing cover member 232, and a driving side cartridge cover member 224 as members. Between the bearing member 45 and the drive-side cartridge cover member 224 , the above-described drive connection portions are provided in order from the bearing member 45 toward the drive-side cartridge cover member 224 .

Even when the developing unit 9 changes its position between the development contact state and the development separation state, it is necessary to reliably transmit the driving force input from the apparatus main body 2 to the developing roller 6 . At least the center line of the release cam 272 is arranged on the same straight line as the rotation axis X. is not on the same straight line with Therefore, when the developing unit 9 changes its position between the development contact state and the development separation state, the relative position between the drive input member 274 and the idler gear 271 changes. Therefore, a universal joint (Oldham's coupling) that can transmit the driving force even if the relative positional deviation occurs is arranged. Specifically, in the present embodiment, the three components of the drive input member 274, the Oldham coupling intermediate body 42, and the idler gear 271 constitute the Oldham coupling. FIG. 20 shows a schematic cross-sectional view of the drive coupling portion. FIG. 20A shows a state in which the drive input portion 74b of the drive input member 74 and the development drive output member 62 of the apparatus body are engaged with each other to transmit the drive to the developing roller 6. FIG. That is, the drive input member 74 is in the first position.

20B shows a state in which the drive input portion 274b of the drive input member 274 is disengaged from the development drive output member 62 of the apparatus main body, and the drive to the development roller 6 is cut off. That is, the drive input member 274 is in the second position.

As can be seen from these figures, the rotation axis of the idler gear 271 is on the rotation axis X. FIG. Further, the Oldham coupling intermediate 42 rotates so as to swing between the rotation axis X and the rotation axis Z. As shown in FIG. Furthermore, the center of the release cam 272 is on the rotation axis X. As shown in FIG.

[Drive release operation]
The operation of the drive connecting portion when the developing roller 6 and the drum 4 change from being in contact with each other to being separated from each other will be described below with reference to FIGS. 7 and 21 to 23. FIG.

21 to 23, some parts are not shown for the sake of explanation, and a part of the structure of the release cam is schematically shown. In this embodiment, the arrow M along the rotation axis X in the drawing indicates the direction toward the outside of the cartridge, and the arrow M along the rotation axis X indicates the direction toward the inside of the cartridge.

[State 1]
As shown in FIG. 7A, the separation force biasing member (body side biasing member) 80 and the biasing force receiving portion (spacing force receiving portion) 45a of the bearing member 45 are separated from each other with a gap d. ing. At this time, the drum 4 and the developing roller 6 are in contact with each other. This state is referred to as state 1 of the separating force biasing member (main body side biasing member) 80 . FIG. 21 shows the configuration of the drive connecting portion at this time.

In FIG. 21A, the pair of drive input member 274 and development drive output member 62 and the pair of release cam 272 and drive side cartridge cover member 224 are schematically shown separately.

FIG. 21(b) shows a perspective view of the configuration of the drive connecting portion. In FIG. 21B, only a portion of the driving side cartridge cover member 224 including the contact portion 224b is shown, and only a portion of the developing device cover member 232 including the guide 232h is shown. Between the contact portion 272a of the release cam 272 and the contact portion 224b of the driving side cartridge cover member 224, there is a gap e. Further, at this time, the drive input member 274 and the development drive output member 62 are engaged with each other with an engagement amount q, so that drive transmission is possible. Further, as described above, the drive input member 274 is engaged with the developing roller gear 69 as a developing roller drive transmission member (see FIG. 12). Therefore, the driving force input from the apparatus main body 2 to the driving input member 274 is transmitted to the developing roller gear 69, and the developing roller 6 is driven. The above state of each part is called a contact position, and is called a development contact/drive transmission state. Further, the position of the drive input member 274 at this time is defined as the first position.

[State 2]
As shown in FIG. 7B, when the separation force biasing member (main body side biasing member) 80 is moved by δ1 in the direction of the arrow F1 in the drawing from the development contact/drive transmission state, as described above, the development occurs. The unit 9 rotates about the rotation axis X in the direction of the arrow K by an angle θ1. As a result, the developing roller 6 is separated from the drum 4 by a distance ε1. The releasing cam 272 and the developing cover member 232 incorporated in the developing unit 9 rotate in the direction of the arrow K by an angle θ1 in conjunction with the rotation of the developing unit 9 . On the other hand, when the cartridge P is attached to the apparatus main body 2 , the drum unit 8 , driving side cartridge cover member 224 and non-driving side cartridge cover member 225 are positioned and fixed to the apparatus main body 2 . That is, as shown in FIGS. 22(a) and 22(b), the contact portion 224b of the driving side cartridge cover member 224 does not move. In the figure, the release cam 272 rotates in the direction of the arrow K in conjunction with the rotation of the developing unit 9, and the contact portion 72a of the release cam 272 and the contact portion 224b of the driving side cartridge cover member 224 contact each other. are starting to come into contact with each other. At this time, the drive input member 274 and the development drive output member 62 are kept engaged with each other (FIG. 22(a)). Therefore, the driving force input from the apparatus main body 2 to the drive input member 274 is transmitted to the developing roller 6 via the developing roller gear 69 . The above-described state of each component is referred to as the development separation/drive transmission state. The position of the drive input member 274 at this time is also the first position.

[State 3]
As shown in FIG. 7(c), when the separation force urging member (main body side urging member) 80 moves in the direction of the arrow F1 in the figure by δ2 from the development separation/drive transmission state, the drive connection portion The configuration is shown in FIGS. 23(a) and 23(b). The releasing cam 272 and the developing cover member 232 rotate in conjunction with the rotation of the developing unit 9 at an angle θ2 (>θ1). On the other hand, the drive-side cartridge cover member 224 does not change its position as described above, and the release cam 272 rotates in the arrow K direction in the figure. At this time, the contact portion 272 a of the release cam 272 receives a reaction force from the contact portion 224 b of the driving side cartridge cover member 224 . Further, as described above, the guide groove 272h of the release cam 272 is engaged with the guide 232h of the developer cover member 232 so that it can only move in the axial direction (directions of arrows M and N). See Figure 10). As a result, the release cam 272 slides in the direction of the arrow N with respect to the developing cover member by the movement amount p. In conjunction with the movement of the release cam 272 in the direction of the arrow N, the pressing surface 272c, which is the biasing portion of the release cam 272 as the biasing member, presses (biases) the pressed surface 274c of the drive input member 274. do. As a result, the drive input member 274 slides in the direction of the arrow N by the movement amount p against the pressing force of the spring 70 (see FIGS. 23 and 12B).

At this time, since the movement amount p is larger than the engagement amount q between the drive input member 274 and the development drive output member 62, the engagement between the drive input member 274 and the development drive output member 262 is released. Along with this, the development drive output member 62 of the apparatus main body 2 continues to rotate, while the drive input member 274 stops. As a result, the developing roller gear 69 and the developing roller 6 stop rotating. The above-described state of each part is called a separated position, and is also called a developing separation/drive cutoff state.

The position of the drive input member 274 at this time is the second position.

In this manner, the drive input member 274 is pressed by the biasing portion 272c of the release cam 272, so that the drive input member 274 moves from the first position to the second position toward the inside of the cartridge along the rotation axis Z. Moving. On the other hand, the idler gear 271 moves on the rotation axis X. As shown in FIG. As a result, the engagement between the drive input member 274 and the development drive output member 62 is released, and the rotational force from the development drive output member 62 is no longer transmitted to the drive input member 274 .

The operation of shutting off the driving of the developing roller 6 in conjunction with the rotation of the developing unit 9 in the direction of the arrow K has been described above. By adopting the above configuration, the developing roller 6 can be separated from the drum 4 while rotating. As a result, the drive to the developing roller 6 can be interrupted according to the separation distance between the developing roller 6 and the drum 4 .

[Drive connection operation]
Next, the operation of the drive connecting portion when the developing roller 6 and the drum 4 change from the separated state to the contact state will be described. This operation is the reverse of the operation from the development contact state to the development separation state described above.

In the development separation state (the development unit 9 is rotated by an angle θ2 as shown in FIG. 7(c)), the drive connection portion is connected to the drive input member 274 and the development drive output member 62 as shown in FIG. is disengaged. That is, the drive input member 274 is in the second position.

From the above state, the developing unit 9 is gradually rotated in the direction of arrow H shown in FIG. 22), the drive input member 274 is moved in the direction of arrow M by the pressing force of the spring 70, so that the drive input member 274 and the development drive output member 62 are engaged with each other.

As a result, the driving force from the apparatus main body 2 is transmitted to the developing roller 6, and the developing roller 6 is rotationally driven. That is, the drive input member 274 is in the first position. At this time, the developing roller 6 and the drum 4 are kept separated from each other.

Further, by gradually rotating the developing unit 9 in the direction of arrow H shown in FIG. 7 from the above state, the developing roller 6 and the drum 4 can be brought into contact with each other. Even in this state, the drive input member 274 is at the first position.

The operation of transmitting the driving force to the developing roller 6 in conjunction with the rotation of the developing unit 9 in the direction of the arrow H has been described above. With the above configuration, the developing roller 6 contacts the drum 4 while rotating, and the drive can be transmitted to the developing roller 6 according to the distance between the developing roller 6 and the drum 4 .

As described above, in this configuration, it is possible to uniquely determine the switching between the cutoff and transmission of drive to the developing roller 6 by the angle at which the developing unit 9 rotates.

In the above description, the contact portion 272a of the release cam 272 and the contact portion 224b of the drive-side cartridge cover member 224 are in face-to-face contact with each other, but this is not necessarily the case.

As described above, the release cam 272 arranged coaxially with the rotation axis X of the developing unit 9 moves in the longitudinal direction (directions of arrows M and N) according to the contact/separation operation of the developing unit 9. The configuration is similar to that of the first embodiment. Especially in the case of this embodiment, the idler gear 271, the Oldham coupling intermediate 42, and the drive input member 74 move in the longitudinal direction (directions of arrows M and N) in conjunction with the rotation of the developing unit 9. there is As a result, the drive input member 274 and the development drive output member 62 can be connected/disconnected.

[Example 3]
Next, a cartridge according to a third embodiment of the invention will be described. In addition, the description is abbreviate|omitted about the structure similar to previous embodiment. The drive input member 374 of this embodiment is configured to be axially movable inside the idler gear 371 as another cartridge-side drive transmission member. That is, unlike the above-described embodiment, the idler gear 371 engaged with the developing roller gear 69 does not need to be moved in the axial direction, so the wear of the idler gear 371 can be reduced.

The engagement relationship between the drive input member 374 and the development drive output member 62 of the apparatus main body in this embodiment is the engagement relationship between the drive input portion 74b of the drive input member 74 and the development drive output member 62 of the apparatus main body in the first embodiment. is equivalent to Further, the configuration of the photoreceptor drive input portion (photoreceptor drive transmission portion) 4a that receives the driving force for rotating the photoreceptor drum 4 is also the same as that of the first embodiment. Furthermore, the engagement relationship between the drive input member 374, the release cam 372, the developing cover member 232, and the driving side cartridge cover member 324 is also the same as in the first embodiment (see FIGS. 10 and 11).

[Construction of Drive Connection Part]
24 and 25, the configuration of the drive connecting portion of this embodiment will be described. The drive connecting portion in this embodiment includes an idler gear 371, a spring 70, a drive input member 374 as other cartridge-side drive transmission members, a release cam 372 as a release member that is a part of the release mechanism, a developing cover member 332, It is composed of the driving side cartridge cover member 324 . Between the bearing member 45 and the drive-side cartridge cover member 324 , the above-described drive connection portions are provided in order on the same straight line from the bearing member 45 toward the drive-side cartridge cover member 324 . That is, the idler gear 371 and the cartridge-side drive transmission member 374, which are other cartridge-side drive transmission members, are coaxially and directly engaged with each other. Also, the bearing member 45 rotatably supports the idler gear 371 . More specifically, the first bearing portion 45p (cylindrical outer surface) of the bearing member 45 rotatably supports the bearing portion 371p (cylindrical inner surface) of the idler gear 371 (see FIGS. 24, 25, and 27). ). Furthermore, the bearing member 45 rotatably supports the developing roller 6 . More specifically, the second bearing portion 45q (cylindrical inner surface) of the bearing member 45 rotatably supports the shaft portion 6a of the developing roller 6. As shown in FIG. A developing roller gear 69 as a developing roller drive transmission member is fitted to the shaft portion 6 a of the developing roller 6 . A gear portion 371 g that meshes with the developing roller gear 69 is provided on the outer peripheral portion of the idler gear 371 . As a result, the rotational force is transmitted from the idler gear 371 to the developing roller 6 via the developing roller gear 69 .

FIG. 26 shows the component configuration of the idler gear 371, the spring 70, and the drive input member 374. As shown in FIG. Also, FIG. 26(b) shows a state in which each part is assembled. The idler gear 371 has a substantially cylindrical shape and has a guide 371a as a first guide portion inside thereof. The guide portion 371a is a shaft portion formed substantially parallel to the rotation axis X. As shown in FIG. On the other hand, the drive input member 374 has a hole portion 374h as a first guided portion. The drive input member 374 can move along the rotation axis X in a state where the hole 374h is engaged with the guide 371a. In other words, the idler gear 371 internally holds the drive input member 374 slidably along its rotational axis. In other words, the drive input member 374 is slidable (reciprocable) in the direction of arrow M or N with respect to the idler gear 371 . The guide portion 371a receives a rotational force for rotating the developing roller 6 from the driving input member 374 by engaging with the hole portion 374h.
Four guides 371a of this embodiment are provided at intervals of 90 degrees so as to surround the rotation axis X as the center. Correspondingly, four holes 374h are provided at intervals of 90 degrees so as to surround the rotation axis X as the center. The number of guides 371a and holes 374h does not necessarily have to be four. It is desirable that a plurality of guides 371a and hole portions 374h be arranged in a circumferential direction around the rotation axis X at equal intervals. In this case, the resultant force acting on the guide 371a or the hole portion 374h acts as a moment to rotate the drive input member 374 and the idler gear 371 about the rotation axis X. FIG. Therefore, it is possible to suppress axial inclination of the drive input member 374 and the idler gear 371 with respect to the rotation axis X. As shown in FIG.

Further, when the drive input member 374 is viewed from the drive input portion 374b side along the direction in which the shaft portion of the drive input member 374 extends, the drive input portion 374b is arranged at the center of the drive input member 374, and the drive input portion 374b is arranged around it. A plurality of holes 374h are arranged, and the periphery thereof serves as a biased portion 374c of the drive input portion 374 that is pressed by the release cam 372. As shown in FIG.

Here, as shown in FIGS. 24 and 25, a release cam 372 is arranged between the drive input member 374 and the developer cover member 332 . As in the first embodiment, the release cam 372 is slidable only in the axial direction (directions of arrows M and N) with respect to the developing cover member 332 (see FIG. 10). Specifically, the drive input member 374 has a shaft-shaped shaft portion 374x, and a drive input portion 74b as a rotational force receiving portion is provided at the end thereof. The shaft portion 374x is combined so as to pass through the opening 372f of the release cam 372, the opening 332d of the developing cover member 332, and the opening 324e of the drive-side cartridge cover portion 324, and the driving input portion 374b at the tip extends outside the cartridge. exposed towards In other words, the drive input portion 374b is arranged to protrude toward the outside of the cartridge from the opening surface of the driving side cartridge cover member 324 provided with the opening portion 324e.

Further, the drive input portion 374b is configured to be movable in the direction toward the inside of the cartridge. That is, the drive input member 374 is retracted toward the inside of the cartridge when the urged portion 374c provided at the base of the shaft portion 374x of the drive input portion 374 is pressed by the release cam 372. As shown in FIG. As a result, it becomes possible to transmit and block the drive input from the main body side drive transmission member 62 .

Next, FIG. 27 shows a schematic cross-sectional view of the drive connecting portion. The cross-sectional view of the drive connecting portion shown in FIG. 27A shows a state in which the drive input portion 374b of the drive input member 374 and the development drive output member 62 are engaged with each other. That is, since the drive input portion 374b is located at a position where drive transmission from the development drive output member 62 is possible, the drive input member 374 is at the first position. Further, the cross-sectional view of the drive connecting portion shown in FIG. 27B shows a state in which the drive input portion 374b of the drive input member 374 and the development drive output member 62 are separated from each other.

That is, since the drive input portion 374b is located at a position where the drive from the development drive output member 62 is not transmitted, the drive input member 374 is at the second position.

As described above, the cylindrical portion 371p of the idler gear 371 and the first bearing portion 45p (outer cylindrical surface) of the bearing member 45 are engaged with each other. Further, the cylindrical portion 371q of the idler gear 371 and the inner diameter portion 332q of the developing device cover member 332 are engaged with each other. That is, the idler gear 371 is rotatably supported at both ends by the bearing member 45 and the developing roller cover member 332, and the drive input member 374 is slidable relative to the idler gear 371 (slidable along the axis of the developing roller). Supported.

Further, the center of the first bearing portion 45p (outer cylindrical surface) of the bearing member 45 and the center of the opening portion 332d provided in the inner diameter portion 332q of the developing device cover member 332 are on the same straight line as the rotation axis X of the developing unit 9. are placed. That is, the drive input member 374 is rotatably supported around the rotation axis X of the developing unit 9 .

A spring 70, which is an elastic member as a biasing member, is provided between the idler gear 371 and the drive input member 374. As shown in FIG. As schematically shown in FIG. 27, the spring 70 is provided inside the idler gear 371 and presses the drive input member 374 in the arrow M direction. That is, the drive input member 374 is configured to be movable inside the idler gear 371 against the elastic force of the spring 70 . The drive input member 374 is configured to be disengaged from the main body drive transmission member 62 by moving inside the idler gear 371 .

27, when the drive input member 374 and other cartridge-side drive transmission members (idler gears 371) are projected onto an imaginary line parallel to the rotation axis of the developing roller 6, part of the drive input member 374 The region and at least a part of the idler gear 371 are configured to overlap each other.

[Drive release/connection operation]
The operation of the drive connecting portion when the developing roller 6 and the drum 4 change from being in contact with each other to the separated state, and when the developing roller 6 and the drum 4 change from being separated from each other to being in contact with each other. The operation of the drive connection is similar to that of the first embodiment. Especially in the configuration of this embodiment, the drive input member 374 is configured to be movable in the axial direction (arrow M and N directions) within the idler gear 371 . That is, it is not necessary to move the idler gear 371 in the axial direction with respect to the developing roller gear 69 when switching between driving cutoff and driving transmission to the developing roller 6 . When each gear is a helical gear, a thrust force (force acting in the axial direction) is generated on the gear tooth surface in the gear drive transmission portion. Therefore, in the case of the first embodiment, in order to move the idler gear 371 in the axial direction (arrow M or N direction), a force is required to resist the thrust force.

On the other hand, in the case of this embodiment, it is not necessary to move the idler gear 371 in the axial direction (arrow M or N direction). The drive input member 374 can be moved in the axial direction (directions of arrows M and N) within the idler gear 371, and as a result, the force required to move the drive input member 374 in the axial direction can be reduced. can.

Furthermore, if the drive input member 374 can be arranged in the inner diameter portion of the idler gear 371, the size of the developing unit 9 as a whole can be reduced in the longitudinal direction. A width 374y of the drive input member 374, a movement space p of the drive input member 374, and a width 371x of the idler gear 371 are required in the axial direction. Here, by disposing at least part of the width 374y of the drive input member 374 and at least part of the movement space p within the width 371x of the idler gear 371, the size of the entire development unit 9 in the longitudinal direction can be reduced. .

[Example 4]
Next, a cartridge according to a fourth embodiment of the invention will be described. In addition, the description is abbreviate|omitted about the structure similar to previous embodiment. The feature of this embodiment is that the configuration of the release mechanism is different from that of the above-described embodiments.

[Construction of Drive Connection Part]
The engagement relationship between the drive input member 374 and the development drive output member 62 of the apparatus main body in this embodiment is the engagement relationship between the drive input portion 74b of the drive input member 74 and the development drive output member 62 of the apparatus main body in the first embodiment. is equivalent to Further, the configuration of the photoreceptor drive input portion (photoreceptor drive transmission portion) 4a that receives the driving force for rotating the photoreceptor drum 4 is also the same as that of the first embodiment. The shapes of the drive input member 474 and the idler gear 471 in this embodiment are the same as those in the third embodiment.

In detail, the configuration of the drive connecting portion of this embodiment will be described with reference to FIGS. 28 and 29. FIG. The drive connecting portion of the present embodiment includes the idler gear 471, the spring 70, the drive input member 474, which are other cartridge-side drive transmission members, and the release cam which is a part of the release mechanism and is a coupling release member and acting member. 472 and the developing cover member 432 . Between the bearing member 45 and the drive-side cartridge cover member 324 , the above-described drive connection portions are provided in order on the same straight line from the bearing member 45 toward the drive-side cartridge cover member 324 . That is, the idler gear 471, which is another cartridge-side drive transmission member, and the cartridge-side drive transmission member 474 are coaxially and directly engaged with each other.

Here, the cartridge-side drive transmission member 474 has a shaft-shaped shaft portion 474x, and a drive input portion 474b as a rotational force receiving portion is provided at the end portion of the shaft portion 474x. The shaft portion 474x is combined so as to pass through the opening 472d of the release cam, the opening 432d of the developing cover member 432, and the opening 424e of the drive-side cartridge cover member 424, and the drive input portion 474b at the tip extends toward the outside of the cartridge. exposed. In addition, the biased portion 474c provided at the base of the shaft portion 474x of the cartridge-side drive transmission member 474 is pressed by the biasing portion 472c of the release cam 472, so that the drive input member 474 moves toward the inside of the cartridge. evacuate.

FIG. 30 shows the relationship between the releasing cam 472 as a coupling releasing member and the developing cover member 432. As shown in FIG. The release cam 472 has a substantially ring-shaped ring portion 472j. The ring portion 472j has an outer peripheral surface serving as the second guided portion. A protruding portion 472i protruding from the ring portion is provided on the outer peripheral portion. In this embodiment, the projecting portion 472i is configured to protrude outward in the radial direction of the ring portion. Further, the developing device cover member 432 has an inner peripheral surface 432i as part of the second guide portion. The inner peripheral surface 432i is configured to engage with the outer peripheral surface of the release cam 472 described above.

The center of the outer peripheral surface of the release cam 472 and the center of the inner peripheral surface 432i of the developing device cover member 432 are both arranged on the same straight line (coaxially) with respect to the rotation axis X. In other words, the release cam 472 is slidably supported in the axial direction and rotatable about the rotation axis X with respect to the developer cover member 432 and the developer unit 9 .

Further, a pressing surface 472c as an urging portion is provided on the surface of the release cam 472 toward the inside of the cartridge (the surface opposite to the direction in which the developing cover member is located). This pressing surface presses (biases) the pressed surface 474c of the drive input member 474, thereby allowing the drive input member 474 to move toward the inside of the cartridge.

Further, the ring portion 472j of the release cam 472 as the coupling release member has a sloped contact portion 472a as a force receiving portion. Further, the developer cover member 432 has a sloped contact portion 432r which corresponds to the contact portion 472a of the release cam and is capable of contacting the contact portion 472a of the release cam. Further, the release cam 472 has a lever portion 472m as a projecting portion projecting in a direction substantially orthogonal to the rotation axis of the developing roller, ie, radially outward of the ring portion.

FIG. 31 shows the configuration of the drive connecting portion and the drive side cartridge cover member 424. As shown in FIG. The lever portion 472m as the projecting portion described above has a force receiving portion 472b as the second guided portion. The force receiving portion 472b receives force from the driving side cartridge cover member 424 by engaging with an engaging portion 424d that is a restricting portion as a part of the second guide portion of the driving side cartridge cover member 424 . The force receiving portion 472b protrudes from an opening 432c provided in a part of the cylindrical portion 432b of the developing device cover member 432 and engages with the engaging portion 424d of the driving side cartridge cover member 424. As shown in FIG. Since the engaging portion 424d and the force receiving portion 472b are engaged with each other, the release cam 472 can slide only in the axial direction (directions of arrows M and N) with respect to the driving side cartridge cover member 424. configuration. Further, as in the above-described embodiment, the outer diameter portion 432a of the cylindrical portion 432b of the developing device cover member 432 slides on the support portion 424a (cylindrical inner surface) as the sliding portion of the driving side cartridge cover member 424. It has become. That is, the outer diameter portion 432a is rotatably coupled to the support portion 424a as a sliding portion.

In the drive switching operation, which will be described later, when the release cam 472 slides in the axial direction (directions of arrows M and N), there is a possibility that the release cam 472 may be axially tilted with respect to the axial direction. There is concern that the drive switching performance, such as the timing of the drive connection/disengagement operation, may be deteriorated due to the occurrence of the shaft tilt. In order to suppress the axial inclination of the release cam 472, the sliding resistance between the outer peripheral surface of the release cam 472 and the inner peripheral surface 432i of the developer cover member 432, and the force receiving portion 472b of the release cam 472 and the driving side cartridge cover member 424 It is preferable to reduce the sliding resistance with the engaging portion 424d. Further, as shown in FIG. 32, the outer peripheral surface 4172i of the release cam 4172 and the inner peripheral surface 4132i of the developing device cover member 4132 are extended in the axial direction to increase the engagement amount of the release cam 4172 in the axial direction. good too.

In view of the above, the release cam 472 is configured so that the inner peripheral surface 432i of the developing device cover member 432, which is a part of the second guide portion, and the engaging portion 424d of the driving side cartridge cover member 424, which is a part of the second guide portion, and . That is, the release cam 472 is slidable (rotatable) in the axial direction (directions of arrows M and N) with respect to the developing unit 9 and in the direction of rotation about the rotation axis X. Further, it is configured to be slidable only in the axial direction (directions of arrows M and N) with respect to the driving side cartridge cover member 424 fixed to the drum unit 8 .

[Relationship between Forces Applied to Each Member of Cartridge]
Next, the relationship of forces applied to each member of the cartridge will be described. FIG. 37(a) is an exploded perspective view of the cartridge P schematically showing forces acting on the developing unit 9, and FIG. 37(b) shows the cartridge P along the rotation axis X direction from the driving side. Fig. 3 shows part of a viewed side view;

The developing unit 9 is acted upon by a reaction force Q1 from the pressure spring 95, a reaction force Q2 received from the drum 4 via the developing roller 6, and its own weight Q3. In addition, during the drive release operation, the release cam 472 engages with the driving side cartridge cover member 424 and receives a reaction force Q4 (details will be described later). A resultant force Q0 of these reaction forces Q1, Q2, Q4 and self weight Q3 is generated by the driving side cartridge cover member 424 which rotatably supports the developing unit 9 and the sliding portion of the non-driving side cartridge cover member 25. It acts on the support portions 424a and 25a as

That is, when the cartridge P is viewed along the axial direction (FIG. 37(b)), the supporting portion 424a as the sliding portion of the driving-side cartridge cover member 424 in contact with the developing cover member 432 is in the direction of the resultant force Q0. is required. That is, the supporting portion 424a as the sliding portion of the drive-side cartridge cover member 424 has a resultant force receiving portion that receives the resultant force Q0 (see FIG. 31). On the other hand, the cylindrical portion 432b of the developer cover member 432 and the support portion 424a of the drive-side cartridge cover member 424 are not necessarily required in directions other than the direction of the resultant force Q0. In this embodiment, in consideration of the above, a part of the cylindrical portion 432b of the developing device cover member 432 that slides on the driving side cartridge cover member 424 and in a direction other than the direction of the resultant force Q0 (in this embodiment, the resultant force An opening 432c is provided on the side opposite to Q0. Further, a releasing cam 472 that engages with the engaging portion 424d, which is the restricting portion of the driving side cartridge cover member 424, is arranged in the opening portion 432c.

[Arrangement Relationship Between Developing Roller, Cartridge Side Drive Transmission Member, and Biasing Force Receiving Portion]
As shown in FIG. 37(b), when the cartridge 9 is viewed from the drive side along the rotation axis of the developing roller, the rotation axis 4z of the photosensitive member 4 and the rotation axis of the cartridge-side drive transmission member 474 (in this embodiment, The rotation axis 6z of the developing roller 6 is arranged between the contact portion 45b of the urging force receiving portion 45a that receives the force from the body-side urging member 80 and the contact portion 45b of the urging force receiving portion 45a. That is, when the cartridge P is viewed from the drive side along the rotation axis of the developing roller, the rotation axis 4z of the photosensitive member 4, the rotation axis x of the cartridge-side drive transmission member 74, and the contact portion of the biasing force receiving portion 45a A rotation axis 6z of the developing roller 6 is arranged in a triangle surrounded by three straight lines connecting 45b.

FIG. 33 shows a schematic cross-sectional view of the drive connecting portion.

The cylindrical portion 471p (cylindrical inner surface) of the idler gear 471 and the first bearing portion 45p (cylindrical outer surface) of the bearing member 45 are engaged with each other. Further, the cylindrical portion 471q (cylindrical outer surface) of the idler gear 471 and the inner diameter portion 432q of the developing device cover member 432 are engaged with each other. That is, the idler gear 471 is rotatably supported at both ends by the bearing member 45 and the developing device cover member 432 .

Further, the shaft portion 474x of the drive input member 474 and the opening portion 432d of the developing device cover member 432 are engaged with each other. Thereby, the drive input member 474 is slidably (rotatably) supported with respect to the developing device cover member 432 .

Further, the center of the first bearing portion 45p (outer cylindrical surface) of the bearing member 45 and the center of the opening 432d provided in the inner diameter portion 432q of the developing device cover member 432 are aligned with the rotation axis X of the developing unit 9. placed on a line. That is, the drive input member 474 is rotatably supported around the rotation axis X of the developing unit 9 .

The sectional view of the drive connecting portion shown in FIG. 33(a) shows a state in which the drive input portion 474b of the drive input member 474 and the development drive output member 62 are engaged with each other. Further, the cross-sectional view of the drive connecting portion shown in FIG. 33(b) shows a state in which the drive input portion 474b of the drive input member 474 and the development drive output member 62 are separated from each other.

[Drive release operation]
The operation of the drive connecting portion when the developing roller 6 and the drum 4 change from being in contact with each other to being separated from each other will be described below with reference to FIGS. 7 and 34 to 36. FIG.

34 to 36, some parts are not shown for the sake of explanation, and a part of the structure of the release cam is schematically shown. In this embodiment, the arrow M along the rotation axis X in the drawing indicates the direction toward the outside of the cartridge, and the arrow M along the rotation axis X indicates the direction toward the inside of the cartridge.

[State 1]
As shown in FIG. 7A, the separation force biasing member (body side biasing member) 80 and the biasing force receiving portion (spacing force receiving portion) 45a of the bearing member 45 are separated from each other with a gap d. ing. At this time, the drum 4 and the developing roller 6 are in contact with each other. This state is referred to as state 1 of the separating force biasing member (main body side biasing member) 80 . FIG. 34 schematically shows the configuration of the drive connecting portion at this time. FIG. 34A schematically shows the pair of the drive input member 474 and the development drive output member 62 and the pair of the release cam 472 and the development cover member 432 separately.

FIG. 34(b) shows a perspective view of the drive connecting portion. In FIG. 34B, only a portion of the developing device cover member 432 including the contact portion 432r is shown, and only a portion of the driving side cartridge cover member 424 including the engaging portion 424d is shown. Between the contact portion 472a of the release cam 472 and the contact portion 432r of the developing device cover member 432, there is a gap e. Further, at this time, the drive input member 474b of the drive input member 474 and the development drive output member 62 are engaged with each other with an engagement amount q, so that drive transmission is possible. Further, as described above, the drive input member 474 is engaged with the idler gear 471 (see FIG. 26). Therefore, the driving force input from the apparatus main body 2 to the driving input member 474 is transmitted via the driving input member 474 to the idler gear 471 and the developing roller gear 69 as a developing roller driving transmission member. Thereby, the developing roller 6 is driven. The above state of each part is called a contact position, and is called a development contact/drive transmission state. Further, the position of the drive input member 474 at this time is defined as the first position.

[State 2]
As shown in FIG. 7B, when the separation force biasing member (main body side biasing member) 80 is moved by δ1 in the direction of the arrow F1 in the drawing from the development contact/drive transmission state, as described above, the development occurs. The unit 9 rotates about the rotation axis X in the direction of the arrow K by an angle θ1. As a result, the developing roller 6 is separated from the drum 4 by a distance ε1. The releasing cam 472 and the developing cover member 432 incorporated in the developing unit 9 rotate in the direction of the arrow K by an angle θ1 in conjunction with the rotation of the developing unit 9 . On the other hand, the release cam 472 is incorporated in the developing unit 9, but as shown in FIG. there is Therefore, even if the developing unit 9 rotates, the position of the release cam 472 does not change. That is, the release cam 472 moves relative to the developing unit 9 . As shown in FIGS. 35(a) and 35(b), the contact portion 472a of the release cam 472 and the contact portion 432r of the developing cover member 432 have begun to contact each other. At this time, the drive input member 474b of the drive input member 474 and the development drive output member 62 are kept engaged with each other (FIG. 35(a)). Therefore, the driving force input from the apparatus main body 2 to the driving input member 474 is transmitted to the developing roller 6 via the driving input member 474 , the idler gear 471 and the developing roller gear 69 . The above-described state of each component is referred to as the development separation/drive transmission state. Note that in state 1 described above, the force receiving portion 472b does not necessarily have to be in contact with the engaging portion 424d of the driving side cartridge cover member 424. FIG. That is, in State 1, the force receiving portion 472b may be arranged with a gap with respect to the engaging portion 424d of the driving side cartridge cover member 424. FIG. In this case, during the operation from state 1 to state 2, the gap between the force receiving portion 472b and the engaging portion 424d of the driving side cartridge cover member 424 disappears, and the force receiving portion 472b moves toward the driving side cartridge cover member 424. contact with the engaging portion 424d. The position of the drive input member 474 at this time is also the first position.

[State 3]
As shown in FIG. 7(c), when the separation force urging member (main body side urging member) 80 moves in the direction of the arrow F1 in the figure by δ2 from the development separation/drive transmission state, the drive connection portion The configuration is shown in FIGS. 36(a) and 36(b). The developing unit cover member 432 rotates in conjunction with the rotation of the developing unit 9 at an angle θ2 (>θ1). At this time, the contact portion 472 a of the release cam 472 receives a reaction force from the contact portion 432 r of the developer cover member 432 . Further, as described above, the force receiving portion 472b of the release cam 472 is engaged with the engaging portion 424d of the drive side cartridge cover member 424 so that the release cam 472 can move only in the axial direction (directions of arrows M and N). It is regulated (see Figure 31). As a result, the release cam 472 slides in the arrow N direction by the movement amount p. In conjunction with the movement of the release cam 472 in the direction of the arrow N, the pressing surface 472c, which is the biasing portion of the release cam 472 as the biasing member, presses (biases) the pressed surface 474c of the drive input member 474. do. As a result, the drive input member 474 slides in the direction of the arrow N by the movement amount p against the pressing force of the spring 70 (see FIGS. 36 and 33(b)).

At this time, since the movement amount p is larger than the engagement amount q between the drive input member 474b of the drive input member 474 and the development drive output member 62, the engagement between the drive input member 474 and the development drive output member 62 is released. . Along with this, the development drive output member 62 continues to rotate, while the drive input member 474 stops. As a result, the idler gear 471, the developing roller gear 69, and the developing roller 6 stop rotating. The above-described state of each part is called a separated position, and is also called a developing separation/drive cutoff state. The position of the drive input member 474 at this time is the second position.

In this way, the drive input member 474 is pushed by the biasing portion 472c of the release cam 472, and the drive input member 474 moves from the first position to the second position toward the inside of the cartridge. As a result, the engagement between the drive input member 474 and the development drive output member 62 is released, and the rotational force from the development drive output member 62 is no longer transmitted to the drive input member 474 .

The operation of shutting off the driving of the developing roller 6 in conjunction with the rotation of the developing unit 9 in the direction of the arrow K has been described above. By adopting the above configuration, the developing roller 6 can be separated from the drum 4 while rotating, and the drive to the developing roller 6 can be cut off according to the separation distance between the developing roller 6 and the drum 4 .

[Drive connection operation]
Next, the operation of the drive connecting portion when the developing roller 6 and the drum 4 change from the separated state to the contact state will be described. This operation is the reverse of the operation from the development contact state to the development separation state described above.

In the development separation state (the development unit 9 is rotated by an angle θ2 as shown in FIG. 7(c)), the drive connection portion is connected to the drive input member 474 and the development drive output member 62 as shown in FIG. is disengaged. That is, the drive input member 474 is in the second position.

From the above state, the developing unit 9 is gradually rotated in the direction of arrow H shown in FIG. 35), the drive input member 474 is moved in the direction of arrow M by the pressing force of the spring 70, so that the drive input member 474b of the drive input member 474 and the development drive output member 62 are engaged with each other. match. As a result, the driving force from the apparatus main body 2 is transmitted to the developing roller 6, and the developing roller 6 is rotationally driven. That is, the drive input member 474 is in the first position. At this time, the developing roller 6 and the drum 4 are kept separated from each other.

Further, from the above state, by gradually rotating the developing unit 9 in the direction of arrow H shown in FIG. 7, the driving input member 474 moves from the second position to the first position, 6 and the drum 4 can be brought into contact. The operation of transmitting the driving force to the developing roller 6 in conjunction with the rotation of the developing unit 9 in the direction of the arrow H has been described above. With the above configuration, the developing roller 6 contacts the drum 4 while rotating, and the drive can be transmitted to the developing roller 6 according to the distance between the developing roller 6 and the drum 4 .

In the above description, the force receiving portion 472b of the release cam 472 is configured to engage with the engaging portion 424d, which is the restricting portion of the driving side cartridge cover member 424, but this is not necessarily the case. It may be configured to engage with the container 26 .

In particular, in the case of this embodiment, the release cam 472 is provided with the contact portion 472a, and the developer cover member 432 is provided with the contact portion 432r as an action portion that contacts the contact portion 472a. Further, the force receiving portion 472b with which the drum unit 8 engages is configured to protrude from an opening portion 432c provided in a part of the cylindrical portion 432b of the developing device cover member 432. As shown in FIG. Therefore, the degree of freedom in arranging the force receiving portion 472b and the engaging portion 424d as a part of the second guide portion acting on the force receiving portion 472b increases. Specifically, as shown in FIG. 11, there is no need to dispose the acting member 24b through the other opening 32j of the developing device cover member 32. As shown in FIG.

[Modification]
Here, in the above description, the process cartridge P detachable from the image forming apparatus was described, but a developing cartridge D detachable from the image forming apparatus as shown in FIG. 38 may be used. FIG. 39(a) is an exploded view of each component arranged at the driving side end of the developing cartridge D, and the description similar to that of the fourth embodiment is omitted.

The release cam 72 as a coupling release member has a force receiving portion 72u that receives force in the direction of the arrow F2 from the main body of the image forming apparatus. When the release cam 72 receives a force in the direction of arrow F2 from the main body of the image forming apparatus, it rotates about the rotation axis X in the direction of arrow H. As shown in FIG. After that, the contact portion 72p as a force receiving portion provided on the release cam 72 receives a reaction force from the contact portion 32r (not shown) of the developing device cover member 32 in the same manner as described above. As a result, the release cam 72 moves in the arrow N direction. As the release cam 72 moves, the drive input member 74 is pushed by the release cam 72 and moves along the axis X toward the inside of the cartridge. As a result, the engagement between the drive input member 74 and the development drive output member 62 is released, and the rotation of the development roller 6 is stopped.

To transmit the drive to the developing roller 6 , the release cam 72 is moved in the direction of arrow M to engage the drive input member 74 and the development drive output member 62 . In this case, the release cam 72 can be moved in the direction of arrow M by using the reaction force of the spring 70 by removing the force acting on the release cam 72 in the direction of arrow F2. As described above, even when the drum 4 and the developing roller 6 are always in contact with each other, the drive transmission to the developing roller 6 can be switched.

As shown in FIG. 39(b), when the cartridge 9 is viewed from the drive side along the rotation axis of the developing roller, the rotation axis of the cartridge-side drive transmission member 74 (in this embodiment, coaxial with the rotation axis X, ) and an urging force receiving portion 72u that is a force receiving portion. That is, with respect to the rotation axis 6z of the developing roller 6, the rotation axis (X) of the biasing force receiving portion 72u and the cartridge-side drive transmission member 74 are arranged on opposite sides.

More specifically, a straight line connecting a contact portion 72b where the biasing force receiving portion 72u contacts the body side biasing member 80 and the rotation axis 6z of the cartridge side drive transmission member 74, and the cartridge side drive transmission member 74 and the rotation axis (X) of the cartridge-side drive transmission member 74 are arranged so as to intersect each other. Further, when the cartridge 9 is viewed along the rotation axis of the developing roller, a line connecting the contact portion 72p and the rotation axis of the cartridge-side drive transmission member 74 is arranged so as to pass through the developing roller 6. there is

In the above description, the form of the developing cartridge D has been described, but the form of the cartridge is not limited to this. That is, the configuration of this embodiment can also be used for the configuration in which the drive transmission to the developing roller is switched while the drum 4 and the developing roller 6 are in contact with each other in the process cartridge P. FIG.

Further, in the above embodiments, the "contact development method" in which the electrostatic latent image on the drum 4 is developed while the drum 4 and the developing roller 6 are in contact with each other has been described. The development method is not limited to this. A "non-contact development method" in which a minute gap is provided between the drum 4 and the developing roller 6 to develop the electrostatic latent image on the drum 4 may be used. As described above, the cartridge detachably attachable to the image forming apparatus may be the process cartridge P having the drum or the developing cartridge D.

[Example 5]
Next, a cartridge according to a fifth embodiment of the invention will be described. In addition, the description is abbreviate|omitted about the structure similar to an old embodiment. This embodiment shows an example in which the configuration of the cover member is different from that of the above-described embodiments.

[Structure of development unit]
40 to 43, the developing unit 9 includes a developing roller 6, a developing blade 31, a developing frame 29, a bearing member 45, and the like.

Further, as shown in FIG. 40, the bearing member 45 is fixed to one longitudinal end of the developing device frame 29 . This bearing member 45 rotatably supports the developing roller 6 . The developing roller 6 has a developing roller gear 69 as a developing roller drive transmission member at its longitudinal end.

Another bearing member 35 is fixed to the driving side cartridge cover member 524 (see FIG. 43). Between the other bearing member 35 and the drive-side cartridge cover member 524, an idler gear 571 for transmitting driving force to the developing roller gear 69, a drive input member 574 for transmitting drive to the idler gear 571 as a drive connecting portion, and the like. is provided.

Another bearing member 35 rotatably supports an idler gear 571 for transmitting driving force to the developing roller gear 69 . The driving side cartridge cover member 524 is provided with an opening 524e. A driving input portion 574b of the driving input member 574 is exposed from the opening 524e so as to protrude toward the outside of the cartridge. This drive input portion 574b engages with the development drive output member 62 (62Y, 62M, 62C, 62K) shown in FIG. Driving force is transmitted from a provided drive motor (not shown). That is, the drive input member 574 functions as a development input coupling. A driving force input from the apparatus main body 2 to the driving input member 574 is transmitted to the developing roller gear 69 and the developing roller 6 via the idler gear 571 . 42 and 43 are perspective views showing the driving side cartridge cover member 524 to which the developing unit 9, the drum unit 8 and other bearing members 35 are fixed. As shown in FIG. 43, the other bearing member 35 is fixed to the driving side cartridge cover member 524. As shown in FIG. Other bearing members 35 are provided with support portions 35a. On the other hand, the developing device frame 29 is provided with a rotation hole 29c (see FIG. 42). When the developing unit 9 and the drum unit 8 are assembled, at one longitudinal end of the cartridge P, the support portion 35a of the other bearing member 35 is fitted into the turning hole 29c of the developing frame 29. As shown in FIG. At the other longitudinal end of the cartridge P, a projecting portion 29b projecting from the developing device frame 29 is fitted into the supporting hole portion 25a of the cartridge cover member on the non-driving side. Thereby, the developing unit 9 is rotatably supported with respect to the drum unit 8 . In this case, the rotation axis X, which is the rotation center of the developing unit 9 with respect to the drum unit 8, connects the center of the support portion 35a of the other bearing member 35 and the center of the support hole portion 25a of the non-driving side cartridge cover member 25. axis line.

[Construction of Drive Connection Part]
The engagement relationship between the drive input member 574 and the development drive output member 62 of the apparatus main body in this embodiment is the engagement relationship between the drive input portion 74b of the drive input member 74 and the development drive output member 62 of the apparatus main body in the first embodiment. is equivalent to Further, the configuration of the photoreceptor drive input portion (photoreceptor drive transmission portion) 4a that receives the driving force for rotating the photoreceptor drum 4 is also the same as that of the first embodiment. Further, the shapes of the drive input member 374 and the idler gear 471 in this embodiment are the same as those in the third embodiment.

In detail, the configuration of the drive connecting portion will be described with reference to FIGS. 40 and 41. FIG. The drive connecting portion in this embodiment includes a bearing member 45 fixed to one longitudinal end of the developing frame 29, an idler gear 571, a spring 70, a drive input member 574, and a release mechanism. It is composed of a release cam 572 as a release member and a driving side cartridge cover member 524 . Between the other bearing member 35 and the drive-side cartridge cover member 524, the above-described drive connection portions are provided in order on the same straight line from the other bearing member 35 toward the drive-side cartridge cover member 524. ing. That is, the idler gear 371, which is another cartridge-side drive transmission member, and the cartridge-side drive transmission member 374 are coaxially and directly engaged with each other.

Another bearing member 35 rotatably supports the idler gear 571 . More specifically, the first bearing portion 35p (cylindrical outer surface) of the other bearing member 35 rotatably supports the bearing portion 571p (cylindrical inner surface) of the idler gear 571 (see FIGS. 40 and 41). .

Here, the cartridge-side drive transmission member 574 has a shaft-shaped shaft portion 574x, and a drive input portion 574b as a rotational force receiving portion is provided at the end portion of the shaft portion 574x. The shaft portion 574x is combined so as to pass through the opening 572d of the release cam and the opening 524e of the drive-side cartridge cover member 524, and the drive input portion 574b at the tip is exposed to the outside of the cartridge. In addition, the biased portion 574c provided at the base of the shaft portion 574x of the cartridge-side drive transmission member 574 is pressed by the biasing portion 572c of the release cam 572, so that the drive input member 574 moves toward the inside of the cartridge. evacuate.

(Release mechanism)
FIG. 44 shows the relationship between the release cam 572 as the coupling release member and the driving side cartridge cover member 524. As shown in FIG. The release cam 572 has a substantially ring-shaped ring portion 572j. The ring portion 572j has an outer peripheral surface serving as the second guided portion. A protruding portion 572i protruding from the ring portion is provided on the outer peripheral portion. In this embodiment, the projecting portion 572i is configured to protrude outward in the radial direction of the ring portion. Further, the driving side cartridge cover member 524 has an inner peripheral surface 524i as part of the second guide portion. The inner peripheral surface 524i is configured to engage with the outer peripheral surface of the release cam 572 described above.

The center of the outer peripheral surface of the release cam 572 and the center of the inner peripheral surface 524i of the driving side cartridge cover member 524 are both arranged on the same straight line (coaxially) with respect to the rotation axis X. That is, the release cam 572 is slidable in the axial direction with respect to the drive-side cartridge cover member 524 and the developing unit 9, and is also slidable (rotatable) in the rotational direction about the rotation axis X. ).

Further, a pressing surface 572c as an urging portion is provided on the surface of the release cam 572 toward the interior of the cartridge (the surface opposite to the direction in which the drive-side cartridge cover member is located). This pressing surface presses (biases) the pressed surface 574c of the drive input member 574, thereby allowing the drive input member 574 to move toward the inside of the cartridge.

Further, the release cam 572 as a coupling release member has a sloped contact portion 572a as a force receiving portion. Further, the drive-side cartridge cover member 524 has a sloped contact portion 524b corresponding to the contact portion 572a of the release cam, capable of coming into contact with the contact portion 572a of the release cam. Further, the release cam 572 has a lever portion 572m as a projecting portion projecting in a direction substantially orthogonal to the rotation axis of the developing roller, ie, radially outward of the ring portion.

FIG. 45 shows the configuration of the drive connecting portion, the drive side cartridge cover member 524, and the bearing member 45. As shown in FIG. The bearing member 45 has an engaging portion 45d that is a restriction portion as part of the second guide portion. This engaging portion 45d is configured to engage with a force receiving portion 572b as a second guided portion of the release cam 572 held between the driving side cartridge cover member 524 and the other bearing member 35. . Since the engaging portion 45d and the force receiving portion 572b are engaged with each other, the release cam 572 is prevented from moving relative to the bearing member 45 and the developing unit 9 around the rotation axis X. Regulated.

FIG. 46 shows a cross-sectional view of the drive connection.

The cylindrical portion 571p of the idler gear 571 and the first bearing portion 35p (outer cylindrical surface) of the other bearing member 35 are engaged with each other. Also, the cylindrical portion 571q of the idler gear 571 and the inner diameter portion 524q of the driving side cartridge cover member 524 are engaged with each other. That is, the idler gear 571 is rotatably supported at both ends by the other bearing member 35 and the driving side cartridge cover member 524 .

Further, the drive input member 574 is rotatably supported with respect to the drive side cartridge cover member 524 by engaging the shaft portion 574x of the drive input member 574 and the opening portion 524e of the drive side cartridge cover member 524 with each other. there is

Furthermore, the center of the first bearing portion 35p (outer cylindrical surface) of the other bearing member 35, the center of the inner diameter portion 524q of the driving side cartridge cover member 524, and the center of the opening portion 524e are aligned with the rotation axis X of the developing unit 9. They are arranged on a straight line (coaxially). That is, the drive input member 574 is rotatably supported around the rotation axis X of the developing unit 9 .

The sectional view of the drive connecting portion shown in FIG. 46(a) shows a state in which the drive input portion 574b of the drive input member 574 and the development drive output member 62 are engaged with each other. That is, it shows a state where the drive input member 574 is at the first position.

Further, the cross-sectional view of the drive connecting portion shown in FIG. 46(b) shows a state in which the drive input portion 574b of the drive input member 574 and the development drive output member 62 are separated from each other. That is, it shows the state where the drive input member 574 is at the second position.

[Drive release operation]
The operation of the drive connecting portion when the developing roller 6 and the drum 4 change from being in contact with each other to being separated from each other will be described below with reference to FIGS. 7 and 47 to 49. FIG.

47 to 49, some parts are not shown for the sake of explanation, and a part of the configuration of the release cam is schematically shown. In this embodiment, the arrow M along the rotation axis X in the drawing indicates the direction toward the outside of the cartridge, and the arrow M along the rotation axis X indicates the direction toward the inside of the cartridge.

[State 1]
As shown in FIG. 7A, the separation force biasing member (body side biasing member) 80 and the biasing force receiving portion (spacing force receiving portion) 45a of the bearing member 45 are separated from each other with a gap d. ing. At this time, the drum 4 and the developing roller 6 are in contact with each other. This state is referred to as state 1 of the separating force biasing member (main body side biasing member) 80 . FIG. 47 shows the configuration of the drive connecting portion at this time. 47A schematically shows the pair of the drive input member 574 and the development drive output member 62 and the pair of the release cam 572 and the drive side cartridge cover member 524 separately.

FIG. 47(b) shows a perspective view of the configuration of the drive connecting portion. In FIG. 47(b), only a portion of the drive-side cartridge cover member 524 including the contact portion 524b is shown, and only a portion of the bearing member 45 including the engaging portion 45d, which is the restricting portion, is shown. Between the contact portion 572a of the release cam 572 and the contact portion 524b of the drive-side cartridge cover member 524, there is a gap e. Further, at this time, the drive input portion 574b of the drive input member 574 and the development drive output member 62 are engaged with each other with an engagement amount q, so that drive transmission is possible (FIG. 47(a)). ). Further, as described above, the drive input member 574 is engaged with the idler gear 571 (see FIG. 26). Therefore, the driving force input from the apparatus main body 2 to the driving input member 574 is transmitted to the developing roller gear 69 via the idler gear 571 . Thereby, the developing roller 6 is driven. The above state of each part is called a contact position, and is called a development contact/drive transmission state. Further, the position of the drive input member 274 at this time is defined as the first position.

[State 2]
As shown in FIG. 7B, when the separation force biasing member (main body side biasing member) 80 is moved by δ1 in the direction of the arrow F1 in the drawing from the development contact/drive transmission state, as described above, the development occurs. The unit 9 rotates about the rotation axis X in the direction of the arrow K by an angle θ1. As a result, the developing roller 6 is separated from the drum 4 by a distance ε1. The bearing member 45 incorporated in the developing unit 9 rotates in the direction of arrow K by an angle θ1 in conjunction with the rotation of the developing unit 9 . On the other hand, although the release cam 572 is incorporated in the drum unit 8, the force receiving portion 572b is engaged with the engaging portion 45d of the bearing member 45 as shown in FIG. Therefore, the release cam 572 rotates in the direction of arrow K in the drum unit 8 in conjunction with the rotation of the developing unit 9 . As shown in FIGS. 48(a) and 48(b), the abutting portion 572a of the release cam 572 and the abutting portion 524b of the drive-side cartridge cover member 524 have begun to contact each other. At this time, the drive input portion 574b of the drive input member 574 and the development drive output member 62 are kept in a mutually engaged state. Therefore, the driving force input from the apparatus main body 2 to the driving input member 574 is transmitted to the developing roller 6 via the driving input member 574 , the idler gear 571 and the developing roller gear 69 . The above-described state of each component is referred to as the development separation/drive transmission state. The position of the drive input member 274 at this time is also the first position.

[State 3]
As shown in FIG. 7(c), when the separation force urging member (main body side urging member) 80 moves in the direction of the arrow F1 in the figure by δ2 from the development separation/drive transmission state, the drive connection portion The configuration is shown in FIGS. 49(a) and 49(b). The bearing member 45 rotates in conjunction with the rotation of the developing unit 9 at an angle θ2 (>θ1). At this time, the contact portion 572 a of the release cam 572 receives a reaction force from the contact portion 524 b of the driving side cartridge cover member 524 . Further, as described above, the force receiving portion 572b of the releasing cam 572 is engaged with the engaging portion 45d of the bearing member 45, and the release cam 572 is moved in the axial direction (directions of arrows M and N) with respect to the developing unit 9. 45). As a result, the release cam 572 slides in the arrow N direction by the movement amount p. Further, in conjunction with the movement of the release cam 572 in the direction of the arrow N, the pressing surface 572c, which is the biasing portion of the release cam 572 as the biasing member, presses (biases) the pressed surface 574c of the drive input member 574. do. As a result, the drive input member 574 slides in the direction of the arrow N by the movement amount p against the pressing force of the spring 70 .

At this time, since the movement amount p is larger than the engagement amount q between the drive input portion 574b of the drive input member 574 and the development drive output member 62, the engagement between the drive input member 574 and the development drive output member 62 is released. . Along with this, the development drive output member 62 continues to rotate, while the drive input member 574 stops. As a result, the idler gear 571, the developing roller gear 69, and the developing roller 6 stop rotating. The above-described state of each part is called a separated position, and is also called a developing separation/drive cutoff state.

The operation of shutting off the driving of the developing roller 6 in conjunction with the rotation of the developing unit 9 in the direction of the arrow K has been described above. By adopting the above configuration, the developing roller 6 can be separated from the drum 4 while rotating, and the drive to the developing roller 6 can be cut off according to the separation distance between the developing roller 6 and the drum 4 . The position of the drive input member 274 at this time is the second position.

In this way, the drive input member 574 is pressed by the biasing portion 572c of the release cam 572, so that the drive input member 574 moves from the first position to the second position toward the inside of the cartridge. move up. As a result, the engagement between the drive input member 574 and the development drive output member 62 is released, and the rotational force from the development drive output member 62 is no longer transmitted to the drive input member 574 .

[Drive connection operation]
Next, the operation of the drive connecting portion when the developing roller 6 and the drum 4 change from the separated state to the contact state will be described. This operation is the reverse of the operation from the development contact state to the development separation state described above.

In the development separation state (the development unit 9 is rotated by an angle θ2 as shown in FIG. 7C), the drive connection portion is connected to the drive input portion 574b of the drive input member 574 and the development unit 574b as shown in FIG. The engagement with the drive output member 62 is released. That is, the drive input member 274 is in the second position.

From the above state, the developing unit 9 is gradually rotated in the direction of arrow H shown in FIG. 48), the drive input member 574 is moved in the direction of arrow M by the pressing force of the spring 70, so that the drive input portion 574b of the drive input member 574 and the developing drive output member 62 are engaged with each other. match. As a result, the driving force from the apparatus main body 2 is transmitted to the developing roller 6, and the developing roller 6 is rotationally driven. That is, the drive input member 274 is in the first position. At this time, the developing roller 6 and the drum 4 are kept separated from each other.

Further, by gradually rotating the developing unit 9 in the direction of arrow H shown in FIG. 7 from the above state, the developing roller 6 and the drum 4 can be brought into contact with each other. Even in this state, the drive input member 574 is at the first position.

The operation of transmitting the driving force to the developing roller 6 in conjunction with the rotation of the developing unit 9 in the direction of the arrow H has been described above. With the above configuration, the developing roller 6 contacts the drum 4 while rotating, and the drive can be transmitted to the developing roller 6 according to the distance between the developing roller 6 and the drum 4 .

In the above description, the force receiving portion 572b of the release cam 572 is configured to engage with the engaging portion 45d, which is the restricting portion of the bearing member 45. However, this is not necessarily the case. It may be configured to engage with. It is also possible to provide the drive input member 574 in the drum unit 8 as in this embodiment.

[Example 6]
Next, a cartridge according to a sixth embodiment of the invention will be described. In addition, the description is abbreviate|omitted about the structure similar to an old embodiment. This embodiment shows an example in which the release cam 672 and the release lever 73 are used in combination.

[Structure of development unit]
As shown in FIGS. 50 and 51, the developing unit 9 has a developing roller 6, a developing blade 31, a developing frame 29, a bearing member 45, a developing cover member 632, and the like.

Further, as shown in FIG. 50, the bearing member 45 is fixed to one longitudinal end of the developing device frame 29 . This bearing member 45 rotatably supports the developing roller 6 . The developing roller 6 has a developing roller gear 69 as a developing roller drive transmission member at its longitudinal end. The bearing member 45 also rotatably supports an idler gear 671 for transmitting driving force to the developing roller gear 69 .

In addition, a drive input member 674 for transmitting drive to the idler gear 671 and the like are sequentially provided as a drive connection portion.

A developing cover member 632 is fixed to the outside of the bearing member 45 in the longitudinal direction of the cartridge P. As shown in FIG. The developing cover member 632 is configured to cover the developing roller gear 69 , the idler gear 671 and the drive transmission member 674 . Further, as shown in FIGS. 50 and 51, the developing cover member 632 is provided with a cylindrical portion 632b. A drive input portion 674b of the drive transmission member 674 is exposed from an opening 632d inside the cylindrical portion 632b so as to protrude toward the outside of the cartridge. This drive input portion (cartridge side drive transmission member) 674b is a main body side drive transmission member shown in FIG. It engages with the development drive output member 62 (62Y, 62M, 62C, 62K), and a driving force from a drive motor (not shown) provided in the apparatus main body 2 is transmitted. That is, the drive transmission member 674 functions as a development input coupling. Therefore, the drive force input from the apparatus main body 2 to the drive transmission member 674 is transmitted to the developing roller gear 69 and the developing roller 6 via the idler gear 671 . The configuration of the drive connecting portion will be described later in detail.

[Assembling the drum unit and developing unit]
As shown in FIGS. 52 and 53, when the developing unit 9 and the drum unit 8 are assembled, the cylindrical portion of the developing cover member 632 is attached to the supporting portion 624a as the sliding portion of the driving side cartridge cover member 624 at one end of the cartridge P. The outer diameter portion 632a of 632b is fitted. At the other end of the cartridge P, a projecting portion 29b projecting from the developing device frame 29 is fitted into the supporting hole portion 25a of the cartridge cover member on the non-driving side. Thereby, the developing unit 9 is rotatably supported with respect to the drum unit 8 . Here, the center of rotation of the developing unit 9 with respect to the drum unit is referred to as a rotation axis X. As shown in FIG. The rotation axis X is an axis connecting the center of the support portion 624a and the center of the support portion 25a.

[Construction of Drive Connection Part]
The engagement relationship between the drive input member 674 and the development drive output member 62 of the apparatus main body in this embodiment is the engagement relationship between the drive input portion 74b of the drive input member 74 and the development drive output member 62 of the apparatus main body in the first embodiment. is equivalent to Further, the configuration of the photoreceptor drive input portion (photoreceptor drive transmission portion) 4a that receives the driving force for rotating the photoreceptor drum 4 is also the same as that of the first embodiment. The shapes of the drive input member 374 and the idler gear 471 in this embodiment are the same as those in the third and fourth embodiments.

In detail, the configuration of the drive connecting portion will be described with reference to FIGS. 50 and 51. FIG. The drive connecting portion in this embodiment includes an idler gear 671 as a cartridge-side drive transmission member, a spring 70 as an elastic member (biasing member), a drive input member 674, a release cam 672, a release lever 73, and a developing cover. It is composed of a member 632 and a driving side cartridge cover member 624 . Between the bearing member 45 and the drive-side cartridge cover member 624 , the above-described drive connection portions are provided in order on the same straight line from the bearing member 45 toward the drive-side cartridge cover member 624 . That is, the idler gear 371, which is another cartridge-side drive transmission member, and the cartridge-side drive transmission member 374 are coaxially and directly engaged with each other. Further, the release lever 73 is a rotating member capable of rotating with respect to the bearing member 45 which is a developing frame.

Here, the cartridge-side drive transmission member 674 has a shaft-shaped shaft portion 674x, and a drive input portion 674b as a rotational force receiving portion is provided at the end thereof. The opening 672d of the release cam, the opening 73d of the release lever 73, the opening 632d of the developing cover member 632, and the opening 624e of the drive-side cartridge cover member 624 are combined so as to pass through them, and the driving input portion 674b at the tip is connected to the cartridge. exposed to the outside. In addition, the biased portion 674c provided at the base of the shaft portion 674x of the cartridge-side drive transmission member 674 is pressed by the biasing portion 672c of the release cam 672, so that the drive input member 674 moves toward the inside of the cartridge. evacuate.

Also, the bearing member 45 rotatably supports the idler gear 671 . More specifically, the first bearing portion 45p (cylindrical outer surface) of the bearing member 45 rotatably supports the bearing portion 671p (cylindrical inner surface) of the idler gear 671 (see FIGS. 50 and 51). Furthermore, the bearing member 45 rotatably supports the developing roller 6 . More specifically, the second bearing portion 45q (cylindrical inner surface) of the bearing member 45 rotatably supports the shaft portion 6a of the developing roller 6. As shown in FIG. A developing roller gear 69 is fitted to the shaft portion 6 a of the developing roller 6 . A gear portion 671 g that meshes with the developing roller gear 69 is provided on the outer peripheral portion of the idler gear 671 . As a result, the rotational force is transmitted from the idler gear 671 to the developing roller 6 via the developing roller gear 69 .

(Release mechanism)
Next, the drive release mechanism will be described.

Here, as shown in FIGS. 50 and 51, between the drive input member 674 and the development drive output member 62, a release cam 672 is arranged as a part of the release mechanism and as a coupling release member. As previously mentioned, the release cam 672 has a substantially ring-shaped ring portion 672j. The ring portion 672j has an outer peripheral portion which is an outer peripheral surface. A protruding portion 672i protruding from the ring portion is provided on the outer peripheral portion. In this embodiment, the protrusion 672i protrudes in the direction along the rotation axis of the developing roller. Further, the developing device cover member 632 has an inner peripheral surface 632i (see FIG. 51). The inner peripheral surface 632 i is configured to engage with the outer peripheral surface of the release cam 672 . Thereby, the release cam 672 is slidably supported with respect to the developing cover member 632 (slidably parallel to the axis of the developing roller 6).

The developing cover member 632 has a guide 632h as a second guide portion, and the release cam 672 has a guide groove 672h as a second guided portion. Here, the guide 632h and the guide groove 672h are formed parallel to the axial direction (arrow M and N directions).

The guide 632 h of the developing cover member 632 engages with the guide groove 672 h of the release cam 672 . Since the guide 632h and the guide groove 672h are engaged with each other, the release cam 672 is slidable only in the axial direction (directions of arrows M and N) with respect to the developing device cover member 632. there is Here, the direction of arrow M is defined as the direction toward the outside of the cartridge, and the direction of arrow N is defined as the direction toward the inside of the cartridge.

FIG. 54 shows a schematic cross-sectional view of the drive connecting portion.

The cylindrical portion 671p (outer cylindrical surface) of the idler gear 671 and the first bearing portion 45p (outer cylindrical surface) of the bearing member 45 are engaged with each other. Further, the cylindrical portion 671q of the idler gear 671 and the inner diameter portion 632q of the developing device cover member 632 are engaged with each other. That is, the idler gear 671 is rotatably supported at both ends by the bearing member 45 and the developer cover member 632 .

Furthermore, the center of the first bearing portion 45p (outer cylindrical surface) of the bearing member 45, the center of the inner diameter portion 632q of the developing device cover member 632, and the center of the hole portion 632p are on the same straight line as the rotation axis X of the developing unit 9. (coaxially). That is, the drive transmission member 674 is rotatably supported around the rotation axis X of the developing unit 9 .

The schematic sectional view of the drive connecting portion shown in FIG. 54(a) shows a state in which the drive input portion 674b of the drive input member 674 and the development drive output member 62 are engaged with each other. That is, the drive input member 674 is in the first position. Further, the schematic cross-sectional view of the drive connecting portion shown in FIG. 53(b) shows a state in which the drive input portion 674b of the drive input member 674 and the development drive output member 62 are separated from each other. That is, the drive input member 674 is in the second position. Here, at least part of the release lever 73 is arranged between the drive input member 674 and the development drive output member 62 .

FIG. 55 shows the configuration of the release cam 672 and the release lever 73 as a rotating member. The release cam 672 as a coupling release member has a contact portion 672a as a force receiving portion (biased portion) and a cylindrical inner surface 672e. Here, the contact portion 672a is inclined with respect to the rotation axis X (parallel to the rotation axis of the developing roller 6). In addition, the release lever 73 has a contact portion 73a as another biasing portion and an outer peripheral surface 73e. Here, the contact portion 73a as another biasing portion is inclined with respect to the rotation axis X. As shown in FIG.

The contact portion 73 a of the release lever 73 is configured to be able to contact the contact portion 672 a of the release cam 672 . Further, the cylindrical inner surface 672e of the release cam 672 and the outer peripheral surface 73e of the release lever 73 are slidably engaged with each other. Further, the respective rotation axes of the outer peripheral surface of the release cam 672, the cylindrical inner surface 672e, and the outer peripheral surface 73e of the release lever 73 are arranged on the same straight line (coaxially). Here, as described above, the outer peripheral surface of the release cam 672 is configured to engage with the inner peripheral surface 632i of the developing device cover member 632 (see FIG. 51). The center of the outer peripheral surface of the release cam 672 and the center of the inner peripheral surface 632i of the developing device cover member 632 are both arranged on the same straight line (coaxially) with respect to the rotation axis X. That is, the release lever 73 is rotatably supported about the rotation axis X with respect to the development unit 9 (development frame 29 ) via the release cam 672 and the development cover member 632 .

Here, the release lever 73 as a rotating member has a substantially ring-shaped ring portion 73j. The ring portion 73j has a contact portion 73a and an outer peripheral surface 73e. Further, the release lever 73 has a lever portion 73m as a projecting portion projecting radially outward from the ring portion 73j in a direction substantially perpendicular to the rotation axis of the developing roller, that is, from the ring portion 73j.

FIG. 56 shows the configuration of the drive connecting portion and the drive side cartridge cover member 624. As shown in FIG. The force receiving portion 73b of the release lever 73 engages with the engaging portion 624d, which is the restricting portion of the driving side cartridge cover member 624, and receives force from the driving side cartridge cover member 624 (part of the photoreceptor frame). The force receiving portion 73b protrudes from an opening 632c provided in a part of the cylindrical portion 632b of the developing device cover member 632, and engages with an engaging portion 624d, which is a restricting portion of the driving side cartridge cover member 624. ing. Since the engaging portion 624d and the force receiving portion 73b are engaged with each other, the release lever 73 is restricted from moving relative to the driving side cartridge cover member 624 about the rotation axis X. .

[Relationship between Forces Applied to Each Member of Cartridge]
Next, the relationship of forces applied to each member of the cartridge will be described. FIG. 60(a) is a perspective view of the cartridge P schematically showing forces acting on the developing unit 9, and FIG. 60(b) is a perspective view of the cartridge P viewed from the drive side along the rotation axis X direction. shows a part of a side view.

The developing unit 9 is acted upon by a reaction force Q1 from the pressure spring 95, a reaction force Q2 received from the drum 4 via the developing roller 6, and its own weight Q3. In addition, during the drive release operation, the release lever 73 engages with the driving side cartridge cover member 624 and receives a reaction force Q4 (details will be described later). The resultant force Q0 of these reaction forces Q1, Q2, Q4 and the weight Q3 is generated by the driving side cartridge cover member 624 and the non-driving side cartridge cover member 625 which rotatably support the developing unit 9. It acts on the support portions 624a and 25a as

That is, when the cartridge P is viewed along the axial direction (FIG. 60(b)), in the direction of the resultant force Q0, there is a support portion 624a as a sliding portion of the drive side cartridge cover member 624 that contacts the developer cover member 632. is required. On the other hand, the cylindrical portion 632b of the developer cover member 632 and the support portion 624a of the drive-side cartridge cover member 624 are not necessarily required in directions other than the direction of the resultant force Q0. In this embodiment, in consideration of the above, the opening 632c is provided in a portion of the cylindrical portion 632b of the developing device cover member 632 that slides on the driving side cartridge cover member 624 and in a direction other than the direction of the resultant force Q0. there is A release lever 73 that engages with an engaging portion 624d that is a restricting portion of the driving side cartridge cover member 624 is arranged in the opening portion 632c.

Further, as shown in FIG. 60(b), when the cartridge 9 is viewed from the drive side along the rotation axis of the developing roller, the rotation axis 4z of the photoreceptor 4 and the rotation axis of the cartridge-side drive transmission member 674 ( X), the contact portion 45p of the biasing force receiving portion 45a that receives the force from the body-side biasing member 80, and the rotational axis 6z of the developing roller 6 are arranged in the same relationship as described in FIG. 37(b). Therefore, the description is omitted.

[Drive release operation]
The operation of the drive connecting portion when the developing roller 6 and the drum 4 change from being in contact with each other to being separated from each other will be described below with reference to FIGS. 7 and 57 to 59. FIG.

57 to 59, some parts are not shown for the sake of explanation, and a part of the structure of the release cam is schematically shown. In this embodiment, the arrow M along the rotation axis X in the drawing indicates the direction toward the outside of the cartridge, and the arrow M along the rotation axis X indicates the direction toward the inside of the cartridge.

[State 1]
As shown in FIG. 7A, the separation force biasing member (main body side biasing member) 80 and the biasing force receiving portion 45a of the bearing member 45 are separated from each other with a gap d. At this time, the drum 4 and the developing roller 6 are in contact with each other. This state is referred to as state 1 of the separating force biasing member (main body side biasing member) 80 . FIG. 57(a) schematically shows the configuration of the drive connecting portion at this time. 57(a) schematically shows the pair of the drive transmission member 674 and the development drive output member 62 and the pair of the release cam 672 and the release lever 73 separately.

FIG. 57(b) shows a perspective view of the configuration of the drive connecting portion. In FIG. 57(b), only a portion of the developing cover member 632 including the guide 632h is shown. There is a gap e between the contact portion 672 a of the release cam 672 and the contact portion 73 a of the release lever 73 . Further, at this time, the drive input portion 74b of the drive input member 674 and the development drive output member 62 are engaged with each other with an engagement amount q, so that the drive can be transmitted. Also, as described above, the drive input member 674 is engaged with the idler gear 671 (see FIG. 26). Therefore, the driving force input from the apparatus main body 2 to the drive transmission member 674 is transmitted to the developing roller 6 via the idler gear 671 and the developing roller gear 69 . The above state of each part is called a contact position, and is called a development contact/drive transmission state. Further, the position of the drive input member 474 at this time is defined as the first position.

[State 2]
When the separation force urging member (main body side urging member) 80 moves in the direction of the arrow F1 in the drawing by δ1 from the developing contact/drive transmission state (see FIG. 7B), the developing unit 9 is moved as described above. rotates about the rotation axis X in the direction of the arrow K by an angle θ1. As a result, the developing roller 6 is separated from the drum 4 by a distance ε1. The releasing cam 672 and the developing cover member 632 incorporated in the developing unit 9 rotate in the direction of the arrow K by an angle θ1 in conjunction with the rotation of the developing unit 9 . On the other hand, although the release lever 73 is incorporated in the developing unit 9, the force receiving portion 73b is engaged with the engaging portion 624d of the driving side cartridge cover member 624 as shown in FIG. Therefore, the force receiving portion 73b is not interlocked with the rotation of the developing unit 9 and does not change its position. That is, the release lever 73 receives a reaction force from the engaging portion 624 d of the driving side cartridge cover member 624 and moves (rotates) relative to the developing unit 9 . FIG. 58(a) schematically shows the configuration of the drive connecting portion at this time. Also, FIG. 58(b) shows a perspective view of the configuration of the drive connecting portion. In the figure, the release cam 672 rotates in the direction of arrow K in conjunction with the rotation of the developing unit 9, and the contact portion 672a of the release cam 672 and the contact portion 73a of the release lever 73 come into contact with each other. It is in a state where it has started. At this time, the drive input portion 74b of the drive input member 674 and the development drive output member 62 are kept engaged with each other. Therefore, the driving force input from the apparatus main body 2 to the drive transmission member 674 is transmitted to the developing roller 6 via the idler gear 671 and the developing roller gear 69 . The above-described state of each component is referred to as the development separation/drive transmission state. Note that in State 1 described above, the force receiving portion 73b does not necessarily have to be in contact with the engaging portion 624d of the driving side cartridge cover member 624. FIG. That is, in State 1, the force receiving portion 73b may be arranged with a gap with respect to the engaging portion 624d of the driving side cartridge cover member 624 . In this case, during the operation from state 1 to state 2, the gap between the force receiving portion 73b and the engaging portion 624d of the driving side cartridge cover member 624 disappears, and the force receiving portion 73b moves toward the driving side cartridge cover member 624. contact with the engaging portion 624d. The position of the drive input member 474 at this time is also the first position.

[State 3]
The configuration of the drive connecting portion when the separating force urging member (main body side urging member) 80 moves in the direction of the arrow F1 in the drawing by δ2 (see FIG. 7(c)) from the developing separation/drive transmission state is shown in FIG. 59. The releasing cam 672 and the developing cover member 632 rotate in conjunction with the rotation of the developing unit 9 at an angle θ2 (>θ1). On the other hand, the release lever 73 does not change its position as described above, and the release cam 672 rotates in the direction of the arrow K in the figure. At this time, the contact portion 672 a of the release cam 672 receives a reaction force from the contact portion 73 a of the release lever 73 . Further, as described above, the guide groove 672h of the release cam 672 is engaged with the guide 632h of the developer cover member 632 so that it can only move in the axial direction (directions of arrows M and N). See Figure 10). As a result, the release cam 672 slides in the arrow N direction by the movement amount p. In conjunction with the movement of the release cam 672 in the direction of the arrow N, the pressing surface 672c of the release cam 672 as the biasing portion presses (applies to) the pressed surface 674c of the drive input member 674 as the biased portion. force). As a result, the drive input member 674 slides in the direction of the arrow N by the movement amount p against the pressing force of the spring 70 . At this time, since the movement amount p is larger than the engagement amount q between the drive input portion 74b of the drive input member 674 and the development drive output member 62, the engagement between the drive input member 674 and the development drive output member 62 is released. . Along with this, the development drive output member 62 continues to rotate, while the drive input member 674 stops. As a result, the idler gear 671, the developing roller gear 69, and the developing roller 6 stop rotating. The above-described state of each part is called a separated position, and is also called a developing separation/drive cutoff state. The position of the drive input member 674 at this time is defined as a second position.

In this way, the drive input member 674 is pushed by the biasing portion 672c of the release cam 672, and the drive input member 674 moves from the first position to the second position toward the inside of the cartridge. As a result, the engagement between the drive input member 674 and the development drive output member 62 is released, and the rotational force from the development drive output member 62 is no longer transmitted to the drive input member 674 .

The operation of shutting off the driving of the developing roller 6 in conjunction with the rotation of the developing unit 9 in the direction of the arrow K has been described above. By adopting the above configuration, the developing roller 6 can be separated from the drum 4 while rotating, and the drive to the developing roller 6 can be cut off according to the separation distance between the developing roller 6 and the drum 4 .

[Drive connection operation]
Next, the operation of the drive connecting portion when the developing roller 6 and the drum 4 change from the separated state to the contact state will be described. This operation is the reverse of the operation from the development contact state to the development separation state described above.

In the development separation state (the development unit 9 is rotated by an angle θ2 as shown in FIG. 7(c)), the drive connection portion is connected to the drive input portion 74b of the drive input member 674 and the development unit 674 as shown in FIG. The engagement with the drive output member 62 is released. That is, the drive input member 674 is in the second position.

From the above state, the developing unit 9 is gradually rotated in the direction of arrow H shown in FIG. , and the state shown in FIG. 58 ), the driving input member 674 moves in the direction of the arrow M due to the pressing force of the spring 70 . As a result, the drive input portion 74b of the drive input member 674 and the development drive output member 62 are engaged with each other. As a result, the driving force from the apparatus main body 2 is transmitted to the developing roller 6, and the developing roller 6 is rotationally driven. That is, the drive input member 674 is in the first position. At this time, the developing roller 6 and the drum 4 are kept separated from each other.

Further, from the above state, by gradually rotating the developing unit 9 in the direction of arrow H shown in FIG. 7, the drive input member 674 moves from the second position to the first position, 6 and the drum 4 can be brought into contact.

The operation of transmitting the driving force to the developing roller 6 in conjunction with the rotation of the developing unit 9 in the direction of the arrow H has been described above. With the above configuration, the developing roller 6 contacts the drum 4 while rotating, and the drive can be transmitted to the developing roller 6 according to the distance between the developing roller 6 and the drum 4 .

As described above, in this configuration, it is possible to uniquely determine the switching between the cutoff and transmission of drive to the developing roller 6 by the angle at which the developing unit 9 rotates.

In the above description, the contact portion 672a of the release cam and the contact portion 73a of the release lever 73 are in face-to-face contact with each other, but this is not necessarily the case. For example, a configuration in which a surface and an edge line, a surface and a point, an edge line and an edge line, or an edge line and a point are in contact with each other may be employed. Further, the force receiving portion 73b of the release lever 73 is configured to engage with the engaging portion 624d, which is the restricting portion of the driving side cartridge cover member 624, but this is not necessarily the case. It may be configured to

According to this embodiment, the developing unit 9 has the release lever 73 and the release cam 672 . The release lever 73 is rotatable about the rotation axis X with respect to the developing unit 9, and is regulated so as not to slide in the axial direction M and the N direction. On the other hand, the release cam 672 can slide in the axial direction M and the N direction with respect to the developing unit 9, and is regulated so as not to rotate about the rotation axis X. As shown in FIG. In other words, there is no component that performs three-dimensional relative movement with respect to the developing unit 9, such as rotation about the rotation axis X and sliding movement in the axial direction M and N direction. In other words, the movement direction of each part is functionally separated by the release lever 73 and the release cam 672 . As a result, the movement of each part becomes two-dimensional, and the operation is stabilized. As a result, the drive transmission to the developing roller 6 in conjunction with the rotation of the developing unit 9 can be performed smoothly.

In this embodiment, in addition to the release cam 672, the release lever 73 is also an urging mechanism, and is slidably supported by the shaft portion 674x of the drive input member 674. As shown in FIG. In this embodiment, when the drive is released, first, the contact portion 672a as the force receiving portion of the release cam 672 and the contact portion 73a of the release lever 73 come into contact. Thereafter, as the release cam 672 moves in the direction of the arrow N, the drive input member 674 retreats toward the inside of the cartridge, thereby releasing the connection with the main body side drive transmission member 62 . ing.

50, the releasing lever 73 and the releasing cam 672 are positioned by engaging the outer peripheral surface 73e of the releasing lever 73 with the cylindrical inner surface 672e of the releasing cam 672 as the coupling releasing member.

However, the configuration is not limited to this, and for example, a configuration as shown in FIG. 61 may be used. That is, the outer peripheral surface 73e of the release lever 73 is slidably supported on the inner peripheral surface 632q of the developer cover member 632, and the cylindrical inner surface 672i of the release cam 672 also slides on the inner peripheral surface 632q of the developer cover member 632. A movably supported configuration may also be used.

[Example 7]
Next, a cartridge according to a seventh embodiment of the invention will be described. In addition, the description is abbreviate|omitted about the structure similar to an old embodiment. This embodiment is similar to the sixth embodiment described above. The difference from the sixth embodiment is that, as shown in the schematic cross-sectional view of FIG. ing.

FIG. 62 is a cross-sectional view of the drive connection viewed from the direction perpendicular to the rotation axis X. FIG.

The sectional view of the drive connecting portion shown in FIG. 62(a) shows a state in which the drive input portion 774b of the drive input member 774 and the development drive output member 62 are engaged with each other. That is, the drive input member 774 is in the first position. In addition, the sectional view of the drive connecting portion shown in FIG. 62(b) shows a state in which the drive input portion 774b of the drive input member 774 and the development drive output member 62 are separated from each other. That is, the drive input member 774h is at the second position.

The release lever 73 is provided in the thickness direction (direction along the rotation axis X) of the cylindrical portion 732b, which is the sliding portion of the developing device cover member 732. As shown in FIG. The cylindrical portion 732 b is a sliding portion of the developer cover member 732 on which the developer cover member slides with respect to the driving side cartridge cover member 724 . In other words, the release lever 73 is provided within a sliding range 724e in which the developer cover member 732 and the driving side cartridge cover member 724 slide in the direction along the rotation axis X. As shown in FIG.

Further, the release lever 73 protrudes from an opening 732c provided in a portion of the cylindrical portion 732b of the developer cover member 732. As shown in FIG.

The positional relationship among the release lever 73, the opening through which the release lever protrudes, the developing cartridge, the drive input section, and the photoreceptor are the same as those shown in FIG. 60 of the sixth embodiment.

Here, as described above, the release lever 73 receives the reaction force Q4 during the drive release operation (see FIG. 60). A force receiving portion 73b where the release lever 73 receives the reaction force Q4 is provided within a sliding range 724e of a supporting portion 724a as a sliding portion where the developing unit 9 slides on the driving side cartridge cover member 724. As shown in FIG. Further, the release lever 73 is supported within a sliding range 724e of a supporting portion 724a as a sliding portion where the developing unit 9 slides on the driving side cartridge cover member 724. As shown in FIG. In other words, the reaction force Q4 received by the release lever 73 is received by the driving side cartridge cover member 724 without being shifted in the rotation axis X direction. Therefore, according to the present embodiment, deformation of the developing device cover member 732 can be suppressed. In addition, since the deformation of the developing device cover member 732 is suppressed, the rotating operation about the rotating axis X of the developing unit 9 with respect to the driving side cartridge cover member 724 can be stably performed. Furthermore, since the release lever 73 is provided in the sliding range 724e of the supporting portion 724a as a sliding portion in which the developing unit 9 slides on the driving side cartridge cover member 724 in the rotation axis X direction, the drive connecting portion, In addition, miniaturization of the process cartridge can be achieved.

In the cartridge of the embodiment described above, the interface portion of the cartridge functions as a clutch that transmits/shuts off the rotational force from the main body of the image forming apparatus to/from the cartridge. The interface portion is a portion where the cartridge and the main body come into contact when the cartridge is attached to the main body of the image forming apparatus. In the above-described embodiment, the cartridge-side drive transmission member 74, which is the cartridge-side interface, is configured to move forward and backward along the direction toward the inside of the cartridge. With such a configuration, the cartridge-side drive transmission member 74 provided at the end of the cartridge in the longitudinal direction functions as a clutch.

The coupling release member 72 of the above embodiment is a biasing mechanism that biases the cartridge side drive transmission member 74, and the cartridge side drive transmission member 74 is moved toward the inside of the cartridge by the coupling release member 72. . This operation releases the coupling between the drive input member 74 and the development drive output member 62 . As the force for urging the cartridge-side drive transmission member 74, for example, the force received from the outside of the cartridge by the urging force receiving portion 45a provided in the cartridge may be used.

Further, in a process cartridge having a photoreceptor and a developing roller, the movement of separating the photoreceptor and the developing roller can be interlocked with the above clutch operation. That is, when the developing unit 9 is rotated with respect to the drum unit 8 so as to separate the photosensitive member and the developing roller, the cartridge-side drive transmission member 74 may be retracted toward the inside of the cartridge along with the rotation. good. From the above state, when the developing unit 9 is rotated in the direction opposite to the above-described rotation with respect to the drum unit 8 so that the photosensitive member and the developing roller come into contact with each other, the cartridge-side drive transmission member is moved along with the rotation. 74 may be configured to protrude toward the outside of the cartridge.

In the above-described embodiment, the drive input member 74 has the biased portion having the pressed surface 74c and the shaft portion 74x having the drive input portion 74b at the tip. The release cam 72 and the release lever 73 are arranged between the biased portion 74 c of the drive input member 74 and the drive input portion 74 b at the tip of the drive input member 74 . Specifically, the shaft portion 74x of the drive input member 74 is slidably arranged so as to pass through openings of the release cam 72 and the release lever.

When the drive is released, the pressing surface 72c as the biasing portion of the release cam 72 presses the pressed surface 74c as the biased portion of the drive input member 74, so that the drive input member 74 moves toward the inside of the cartridge. evacuate.

Further, the pressing surface 72c as the biasing portion of the release cam 72 and the pressed surface 74c as the biased portion of the drive input member 74 each have a surface substantially orthogonal to the rotation axis of the developing roller. is doing. However, the biasing portion 72c of the release cam 72 and the pressed surface 74c as the biased portion of the drive input member 74 do not necessarily have to be surfaces. As long as the release cam 72 can press the drive input member 74 , it may be configured to contact by combining surfaces, ridges, and points.

REFERENCE SIGNS LIST 1 image forming apparatus 4 photoreceptor 6 developing roller 8 drum unit 9 developing unit 24 photoreceptor frame (drive side cartridge cover)
29 development frame 32 development frame (development cover member)
45 developing frame (bearing member)
45a Biasing force receiving portion 62 Main body side drive transmission member 72 Coupling release member (release cam)
72a force receiving portion 72c biasing portion 73 release lever 74 cartridge side drive transmission member 80 main body side biasing member X rotation axis of the developing unit with respect to the drum unit

Claims (11)

a developing roller in the cartridge;
a driving input member for receiving driving force for rotating the developing roller from the outside of the cartridge;
a lever movable between a first position and a second position;
has
(a) the drive input member moves toward the outside of the cartridge when the lever moves from the second position to the first position; and (b) the lever moves from the first position to the second position. configured to move toward the interior of the cartridge by moving to a position;
When the cartridge takes a posture in which the developing roller is positioned below the cartridge and the axis of the developing roller is positioned below the axis of the drive input member, the lever is positioned below the cartridge. located cartridge. a developing roller in the cartridge;
a driving input member for receiving driving force for rotating the developing roller from the outside of the cartridge;
a lever movable between a first position and a second position;
has
(a) when the lever is at the first position, the drive input member protrudes from the frame of the cartridge; (b) when the lever is at the second position, the drive input member is at a retracted position that is retracted into the cartridge from the projecting position;
When the cartridge takes a posture in which the developing roller is positioned below the cartridge and the axis of the developing roller is positioned below the axis of the drive input member, the lever is positioned below the cartridge. located cartridge. The lever protrudes downward when the cartridge takes a posture in which the developing roller is positioned below the cartridge and the axis of the developing roller is positioned below the axis of the drive input member. 3. The cartridge according to claim 1 or 2. 4. The cartridge according to any one of claims 1 to 3, wherein the cartridge further comprises a photosensitive drum, and the lever is movable between the first position and the second position while the developing roller is in contact with the photosensitive drum. or the cartridge according to item 1. in the cartridge,
a developing roller;
a driving input member for receiving driving force for rotating the developing roller from the outside of the cartridge;
an urging force receiving portion configured to receive an urging force from the outside of the cartridge, the urging force receiving portion being movable between a first position and a second position;
has
(a) the force receiving portion moves toward the outside of the cartridge when the force receiving portion moves from the second position to the first position; configured to move toward the interior of the cartridge by moving from a first position to the second position;
When the cartridge assumes a posture in which the developing roller is positioned below the cartridge and the axis of the developing roller is positioned below the axis of the drive input member, the urging force receiving portion acts on the cartridge. The cartridge located at the bottom of the . a developing roller in the cartridge;
a driving input member for receiving driving force for rotating the developing roller from the outside of the cartridge;
an urging force receiving portion configured to receive an urging force from the outside of the cartridge, the urging force receiving portion being movable between a first position and a second position;
has
The drive input member is configured to be movable in association with the movement of the biasing force receiving portion, and (a) when the biasing force receiving portion is at the first position, the drive input member moves the cartridge. (b) when the biasing force receiving portion is at the second position, the drive input member is at a retracted position retracted into the cartridge from the projecting position;
When the cartridge assumes a posture in which the developing roller is positioned below the cartridge and the axis of the developing roller is positioned below the axis of the drive input member, the urging force receiving portion acts on the cartridge. The cartridge located at the bottom of the . 7. The cartridge according to claim 5, wherein the biasing force receiving portion is arranged at a position different from the drive input member. 6. The cartridge further comprises a photoreceptor drum, and the biasing force receiving portion is movable between the first position and the second position when the developing roller is in contact with the photoreceptor drum. 8. The cartridge according to any one of 7. 9. A cartridge according to claim 1 or 8, further comprising a spring that biases said drive input member toward the outside of said cartridge. 10. The cartridge according to any one of claims 1 to 9, wherein the drive input member is movable in the axial direction of the drive input member. An image forming apparatus comprising: the cartridge according to any one of claims 1 to 9; and an image forming apparatus main body to which the cartridge is mountable.

Images