BR112017021391B1 - DEVELOPING CARTRIDGE, PROCESSING CARTRIDGE AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS - Google Patents

Abstract

CARTRIDGE, PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS. The present invention relates to a process cartridge that can be detachably mounted to an electrophotographic image forming apparatus, including a drive transmission element on the main assembly side and a impulse element on the main assembly side. the cartridge including a rotating photosensitive drum; a rotating developing roller for developing a latent image formed on the drum, the developing roller may be placed in contact with and spaced from the drum; a thrust force receiving part for receiving a thrust force from the thrust member to space the drum roller; a drive transmission part on the cartridge side capable of coupling with the drive transmission element on the side of the main assembly to receive a rotational force for rotating the roller; a release member capable of driving the drive transmission element on the main assembly side to decouple the drive transmission element on the cartridge side from the drive transmission element on the main assembly side by the part of (... ).

Description

Field of Invention

[0001] The present invention relates to an electrophotographic image forming apparatus (image forming apparatus) and a cartridge detachably mountable to a main assembly of the image forming apparatus.

[0002] The image forming apparatus forms an image on a recording material using an electrophotographic image forming process. Examples of the image forming apparatus include an electrophotographic copying machine, an electrophotographic printer (laser beam printer, LED printer, or printer, for example), a fax machine, a word processor, and so on.

[0003] A cartridge is a unit detachably mountable to a main assembly of the image forming apparatus (main assembly). For example, the process cartridge may comprise an electrophotographic photosensitive drum and at least one process device actuatable on the drum (developer support element (developer roller), for example) that are unified in a cartridge.

[0004] The cartridge may comprise the drum and the developing roller as a unit, or it may comprise the drum, or it may comprise the developing roller. A cartridge comprising the drum is a drum cartridge, and the cartridge comprising the developing roller is a developing cartridge.

[0005] The main assembly of the image forming apparatus is parts of the image forming apparatus other than the cartridge.

Fundamentals of Invention

[0006] In a conventional image forming apparatus, a drum and actuable process devices on the drum are unified into a cartridge that can be detachably mounted to a main assembly of the apparatus (cartridge type).

[0007] With such a type of cartridge, maintenance operations for the image forming apparatus can be carried out effectively by the user without relying on a maintenance person and therefore operability can be improved considerably. Therefore, the process cartridge type is widely used in the field of image forming apparatus.

Summary of the Invention [Technical problem]

[0008] A process cartridge (Japanese Patent Application submitted for public inspection 2001-337511, for example), and an image forming apparatus (Japanese Patent Application submitted for public inspection 2003-208024, for example) have been proposed, in which a clutch is provided to effect switching to drive the developing roller during an image forming operation and to turn off driving the developing roller during a non-image forming operation.

[0009] It is an object of the present invention to improve a structure for switching the drive transmission for the developing roller.

[Problem solution]

[0010] In accordance with one aspect of the present invention, there is provided a detachably mountable process cartridge to a main assembly of the electrophotographic image forming apparatus, including a drive transmission element on the side of the main assembly and a thrust on the side of the main assembly, said process cartridge comprising (i) a rotating photosensitive element; (ii) a rotating developing roller configured to reveal a latent image formed on said photosensitive element, said developing roller being capable of contacting and spacing said photosensitive element; (iii) an impulse force receiving part configured to receive an impulse force from the impulse element on the side of the main assembly to space said developing roller from said photosensitive element; (iv) a drive transmission element on the cartridge side capable of coupling with the drive transmission element on the main assembly side to receive a rotational force for rotating said developing roller; (v) a release member capable of driving the drive transmission element on the main assembly side to decouple said drive transmission element on the cartridge side from the drive transmission element on the main assembly side by said receiving part of thrust force that receives the thrust force from the thrust element on the side of the main assembly.

[0011] According to another aspect of the present invention, there is provided a process cartridge for electrophotographic image formation, which comprises (i) a rotating photosensitive element; (ii) a rotating developing roller configured to reveal a latent image formed on said photosensitive element, said developing roller being capable of contacting and spacing from said photosensitive element; (iii) an impulse force receiving part configured to receive an impulse force to space said developing roller from said photosensitive element; (iv) a rotational force receiving part configured to receive a rotational force to rotate said developing roller from an exterior of said process cartridge; and (v) a movable element moving relative to the rotational force receiving part in at least one longitudinal direction of said developing roller, said movable member being moved outwardly in the longitudinal direction by said impulse force receiving part which receives the impulse force.

[0012] According to another aspect of the present invention, there is provided a process cartridge detachably mountable to a main assembly of the electrophotographic image forming apparatus, including a drive transmission element on the side of the main assembly, said process cartridge comprising: (i) a photosensitive element; (ii) a photosensitive element support rotatably supporting said photosensitive element; (iii) a developing roller configured to reveal a latent image formed on said photosensitive element; (iv) a developing device support rotatably supporting said developing roller, said developing device support being movable with respect to said photosensitive element support; (v) a drive transmission element on the cartridge side capable of coupling with the drive transmission element on the main assembly side to receive a rotational force for rotating said developing roller; and (vi) a release member capable of driving the drive transmission element on the main assembly side to decouple said drive transmission element on the cartridge side from the drive transmission element on the main assembly side by movement of said support of the developing device in relation to said support of the photosensitive element.

[0013] According to a further aspect of the present invention, a process cartridge for electrophotographic image formation is provided, which comprises: (i) a photosensitive element; (ii) a photosensitive element support rotatably supporting said photosensitive element; (iii) a developing roller configured to reveal a latent image formed on said photosensitive element; (iv) a developing device support rotatably supporting said developing roller, said developing device support being movable with respect to said photosensitive element support; (v) a rotational force receiving part configured to receive a rotational force to rotate said developing roller from an exterior of said process cartridge; and (vi) a movable element moving relative to said rotational force receiving part in at least one longitudinal direction of said developing roller, said movable element being externally movable in the longitudinal direction by such movement of said device support. of development that said development roller is away from said photosensitive element.

[0014] In accordance with another aspect of the present invention, there is provided a cartridge detachably mountable to a main assembly of the electrophotographic image forming apparatus including a drive transmission element on the side of the main assembly and a impulse element on the side of a main assembly, comprising: (i) a rotating developing roller configured to reveal a latent image formed on said photosensitive element; (ii) an impulse force receiving part configured to receive impulse force from the impulse element on the side of the main assembly; (iii) a drive transmission element on the cartridge side capable of coupling with the drive transmission element on the main assembly side to receive a rotational force for rotating said developing roller; (iv) a release member capable of driving the drive transmission element on the main assembly side to decouple said drive transmission element on the cartridge side from the drive transmission element on the main assembly side by said receiving part of thrust force that receives the thrust force from the thrust element on the side of the main assembly.

[0015] According to another aspect of the present invention, there is provided a cartridge for forming an electrophotographic image, comprising: (i) a rotating developing roller configured to reveal a latent image formed on a photosensitive element; (ii) a rotational force receiving part configured to receive a rotational force to rotate said developing roller, from an exterior of said cartridge; (iii) an impulse force receiving part configured to receive an impulse force from an exterior of said cartridge; and (iv) a movable element that is movable with respect to the rotational force receiving part in at least one longitudinal direction of said developing roller, said movable member being externally movable in the longitudinal direction by said impulse force receiving part which receives the impulse force.

Advantageous effects of the invention

[0016] According to the present invention, switching the drive for the developing roller can be carried out between the cartridge and the main assembly of the image forming apparatus.

[0017] These and other objects, features and advantages of the present invention will become more evident upon consideration of the following description of embodiments of the present invention taken in conjunction with the attached drawings.

Brief Description of the Drawings

[0018] Figure 1 is an exploded perspective view of a structure and adjacent a drive connecting part of a Process Cartridge, according to a first embodiment, as viewed from a drive side.

[0019] Figure 2 is a sectional view of an image forming apparatus according to the first embodiment.

[0020] Figure 3 is a perspective view of the image forming apparatus according to the first embodiment.

[0021] Figure 4 is a sectional view of the Process Cartridge, according to the first embodiment.

[0022] Figure 5 is an exploded perspective view of the Process Cartridge, in accordance with the first embodiment, as seen from the drive side.

[0023] Figure 6 is an exploded perspective view of the Process Cartridge, in accordance with the first embodiment, as viewed from a non-drive side.

[0024] Parts (a), (b) and (c) of Figure 7 are side views of the Process Cartridge, according to the first embodiment, in which part (a) shows a state in which a developing roller is in contact with a drum, part (b) shows a state in which an impulse force receiving part has moved through a distance δ1, and part (c) shows a state in which the impulse force receiving part has moved through a distance δ1, and part (c) shows a state in which the impulse force receiving part impulse force moved through a distance δ2.

[0025] Figure 8 is an exploded perspective view of a structure and adjacent to the drive connection part of the Process Cartridge, according to the first embodiment, viewed from the non-drive side.

[0026] Parts (a) and (b) of Figure 9 are schematic cross-sectional views of and adjacent to a cartridge drive transmission element in accordance with the first embodiment, in which part (a) shows a state of drive transmission, and part (b) shows a drive disconnection state.

[0027] Figure 10 is a schematic exploded view of a release cam, a spring and the cover element of the developing device.

[0028] Figure 11 is a schematic exploded view of the release cam and release lever in the first embodiment.

[0029] Figure 12 is a schematic view of the drive transmission element on the cartridge side and the release element, their peripheral parts, and a cartridge cover element on the drive side, in the first embodiment.

[0030] Parts (a) and (b) of Figure 13 are schematic views and adjacent to the drive transmission element on the cartridge side in the state of contact and drive transmission in the first embodiment, wherein (a) is a schematic sectional view of the drive connection part, e) is a perspective view of the drive connection part.

[0031] Parts (a) and (b) of Figure 14 are schematic views and adjacent to the drive transmission element on the cartridge side in the state of separation from the developing device and in the state of drive transmission in the first embodiment, in which (a) is a schematic cross-sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0032] Parts (a) and (b) of Figure 15 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of separation from the developing device and in the state of drive disconnection in the first embodiment, in which (a) is a schematic cross-sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0033] Parts (a) and (b) of Figure 16 are schematic cross-sectional views of the drive connection part, in which (a) shows the drive transmission, and (b) shows the drive disconnection.

[0034] Figure 17 is a schematic sectional view of the drive connection part according to a modified example of the first embodiment.

[0035] Parts (a) and (b) of Figure 18 are illustrations of the drive disconnection state in a modified example of the first embodiment, wherein (a) is a schematic cross-sectional view of the drive connection part and ( b) is a perspective view of the drive connection part.

[0036] Parts (a) and (b) of Figure 19 are illustrations of the drive disconnection state in a modified example of the first embodiment, wherein (a) is a schematic cross-sectional view of the drive connection part and ( b) is a perspective view of the drive connection part.

[0037] Figure 20 is a block diagram of a gear arrangement in a conventional example.

[0038] Figure 21 is an adjacent, exploded perspective view of the drive connecting part of the Process Cartridge, according to a second embodiment, as seen from a drive side.

[0039] Figure 22 is an adjacent, exploded perspective view of the drive connecting portion of the Process Cartridge, in accordance with the second embodiment, as viewed from a non-drive side.

[0040] Parts (a) and (b) of Figure 23 are schematic and adjacent cross-sectional views of the drive transmission element on the cartridge side according to the second embodiment, in which (a) shows a transmission state of drive, and (b) shows a drive disconnect state.

[0041] Figure 24 is a schematic exploded view of a release cam, a release lever and a cover element of the developing device in the second embodiment.

[0042] Figure 25 is a schematic exploded view of the release cam and release lever in the second embodiment.

[0043] Figure 26 is a schematic view of the drive transmission element on the cartridge side and the release element, their peripheral parts, and a cartridge cover element on the drive side, in the second embodiment.

[0044] Parts (a) and (b) of Figure 27 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of contact and drive transmission in the second embodiment, wherein (a) is a schematic sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0045] Parts (a) and (b) of Figure 28 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of separation from the developing device and in the state of drive transmission in the second embodiment, in which (a) is a schematic cross-sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0046] Parts (a) and (b) of Figure 29 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of separation from the developing device and in the state of drive disconnection in the second embodiment, in which (a) is a schematic cross-sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0047] Figure 30 is an adjacent, exploded perspective view of a drive connecting portion of a Process Cartridge, in accordance with a third embodiment, as viewed from a drive side.

[0048] Figure 31 is an adjacent, exploded perspective view of the drive connecting portion of the Process Cartridge, in accordance with the third embodiment, as viewed from a non-drive side.

[0049] Parts (a) and (b) of Figure 32 are schematic and adjacent cross-sectional views of the drive transmission element on the cartridge side according to the third embodiment, wherein (a) shows a transmission state of drive, and (b) shows a drive disconnect state.

[0050] Figure 33 is a schematic exploded view of the cover element of the developing device and the release cam according to the third embodiment.

[0051] Figure 34 is a schematic view of the drive transmission element on the cartridge side and the release element, their peripheral parts and a cartridge cover element on the drive side, in the third embodiment.

[0052] Parts (a) and (b) of Figure 35 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of contact and drive transmission in the third embodiment, wherein (a) is a schematic sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0053] Parts (a) and (b) of Figure 36 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of separation from the developing device and in the state of drive transmission in the third embodiment, in which (a) is a schematic cross-sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0054] Parts (a) and (b) of Figure 37 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of separation from the developing device and in the state of drive disconnection in the third embodiment, in which (a) is a schematic cross-sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0055] Figure 38 is an adjacent, exploded perspective view of a drive connecting part of a Process Cartridge, according to a fourth embodiment, viewed from a drive side.

[0056] Figure 39 is an adjacent, exploded perspective view of the drive connecting portion of the Process Cartridge, in accordance with the fourth embodiment, as viewed from a non-drive side.

[0057] Parts (a) and (b) of Figure 40 are schematic and adjacent cross-sectional views of the drive transmission element on the cartridge side according to the fourth embodiment, in which (a) shows a transmission state of drive, and (b) shows a drive disconnect state.

[0058] Figure 41 is a schematic exploded view of a release cam and a cover element of the developing device in the fourth embodiment.

[0059] Figure 42 is a schematic view of the drive transmission element on the cartridge side and the release element, their peripheral parts, and a cartridge cover element on the drive side, in the fourth embodiment.

[0060] Parts (a) and (b) of Figure 43 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of contact and drive transmission in the fourth embodiment, wherein (a) is a schematic sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0061] Parts (a) and (b) of Figure 44 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of separation from the developing device and in the state of drive transmission in the fourth embodiment, in which (a) is a schematic cross-sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0062] Parts (a) and (b) of Figure 45 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of separation from the developing device and in the state of drive disconnection in the fourth embodiment, in which (a) is a schematic cross-sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0063] Figure 46 is an adjacent, exploded perspective view of a drive connecting part of a Process Cartridge, in accordance with a fifth embodiment, viewed from a drive side.

[0064] Figure 47 is an adjacent, exploded perspective view of the drive connecting portion of the Process Cartridge, in accordance with the fifth embodiment, as viewed from a non-drive side.

[0065] Parts (a) and (b) of Figure 48 are schematic and adjacent cross-sectional views of the drive transmission element on the cartridge side according to the fifth embodiment, wherein (a) shows a transmission state of drive, and (b) shows a drive disconnect state.

[0066] Figure 49 is a schematic exploded view of a release cam and a covering element of the developing device in the fifth embodiment.

[0067] Figure 50 is a schematic view of the drive transmission element on the cartridge side and the release element, their peripheral parts, and a cartridge cover element on the drive side, in the fifth embodiment.

[0068] Parts (a) and (b) of Figure 51 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of contact and drive transmission in the fifth embodiment, wherein (a) is a schematic sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0069] Parts (a) and (b) of Figure 52 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of separation from the developing device and in the state of drive transmission in the fifth embodiment, in which (a) is a schematic cross-sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0070] Parts (a) and (b) of Figure 53 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of separation from the developing device and in the state of drive disconnection in the fifth embodiment, in which (a) is a schematic cross-sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0071] Figure 54 is an adjacent, exploded perspective view of a drive connecting part of a Process Cartridge, according to a sixth embodiment, viewed from a drive side.

[0072] Figure 55 is an adjacent, exploded perspective view of the drive connecting portion of the Process Cartridge, in accordance with the sixth embodiment, as viewed from a non-drive side.

[0073] Parts (a) and (b) of Figure 56 are schematic and adjacent cross-sectional views of the drive transmission element on the cartridge side according to the sixth embodiment, wherein (a) shows a transmission state of drive, and (b) shows a drive disconnect state.

[0074] Figure 57 is a schematic exploded view of a rolling element, a release element and a drive input element in the sixth embodiment.

[0075] Figure 58 is a schematic view of the drive transmission element on the cartridge side and the release element, their peripheral parts and a cartridge cover element on the drive side, in the sixth embodiment.

[0076] Parts (a) and (b) of Figure 59 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of contact and drive transmission in the sixth embodiment, wherein (a) is a schematic sectional view of the drive connecting part, and (b) is a perspective view of the drive connecting part.

[0077] Parts (a) and (b) of Figure 60 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of separation from the developing and drive transmission device in the sixth embodiment, wherein ( a) is a schematic sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0078] Parts (a) and (b) of Figure 61 are schematic and adjacent views of the drive transmission element on the cartridge side in the state of separation from the developing device and in the state of drive disconnection in the sixth embodiment, in which (a) is a schematic cross-sectional view of the drive connection part, and (b) is a perspective view of the drive connection part.

[0079] Figure 62 is an exploded perspective view of a drive connection part of a Process Cartridge, according to a seventh embodiment.

[0080] Figure 63 is a perspective view of a developing cartridge according to an eighth embodiment.

Detailed Description of the Invention [Mode 1] [General arrangement of electrophotographic image forming apparatus]

[0081] A first embodiment of the present invention will be described with reference to the attached drawings.

[0082] An example of the image forming apparatus of the following embodiments is a four-color image forming apparatus to which four process cartridges can be detachably mounted. The number of process cartridges mountable to the imaging apparatus is not limited to this example. It is selected appropriately as desired. For example, in the case of a monochrome image forming apparatus, the number of process cartridges mounted to the image forming apparatus is one. Examples of image forming apparatus of the following embodiments are printers.

[General arrangement of image forming apparatus]

[0083] Figure 2 is a schematic section of the electrophotographic image forming apparatus of this embodiment, which can form an image on a recording material. Part (a) of Figure 3 is a perspective view of the image forming apparatus of this embodiment. Figure 4 is a sectional view of a process cartridge P of this embodiment. Figure 5 is a perspective view of the process cartridge P of this embodiment, as viewed from a drive side, and Figure 6 is a perspective view of the process cartridge P of this embodiment viewed from a non-drive side. drive.

[0084] As shown in Figure 2, the imaging apparatus 1 is a four-color laser beam printer, using an electrophotographic imaging process to form a color image on a recording material S. The imaging apparatus image formation 1 is of a type of process cartridge, in which the process cartridges are detachably mounted to a main assembly 2 of the electrophotographic image forming apparatus to form the color image on the recording material S. process is a cartridge for electrophotographic image formation.

[0085] Here, a side of the image forming apparatus 1 which is provided with a front port 3 is a front side, and a side opposite the front side is a rear side. Furthermore, a right side of the image forming apparatus 1 as viewed from the front side is a drive side, and a left side is a non-drive side. Figure 2 is a sectional view of the image forming apparatus 1 as viewed from the non-drive side, in which a front side of the drawing sheet is the non-drive side of the image forming apparatus 1, the The right side of the drawing sheet is the front side of the image forming apparatus 1, and the rear side of the drawing sheet is the drive side of the image forming apparatus 1.

[0086] In the main assembly 2 of the image forming apparatus, P process cartridges (PY, PM, PC, PK) are provided including a first PY process cartridge (yellow), a second PM process cartridge (magenta), a third PC process cartridge (cyan) and a fourth PK process cartridge (black), which are arranged in the horizontal direction.

[0087] The first to fourth P process cartridges (PY, PM, PC, PK) include similar electrophotographic image formation process mechanisms, although the colors of the developers contained therein are different. For the first to fourth process cartridges P (PY, PM, PC, PK), rotational forces are transmitted from the drive output parts of the main assembly 2 of the image forming apparatus. This will be described in detail below.

[0088] Additionally, the first through fourth P process cartridges (PY, PM, PC, PK) are provided with bias voltages (charge bias voltages, develop bias voltages, and so on) (not shown) , from the main assembly 2 of the image forming apparatus.

[0089] As shown in Figure 4, each of the first through fourth process cartridges P (PY, PM, PC, PK) includes a photosensitive drum unit 8. The photosensitive drum unit 8 is provided with a drum (photosensitive drum ) 4, a loading device, and a cleaning device as a process device actuable on the drum 4.

[0090] Furthermore, each of the first to fourth P process cartridges (PY, PM, PC, PK) includes a developing unit 9 provided with a developing device for developing an electrostatic latent image on the drum 4.

[0091] The first process cartridge PY accommodates a yellow developer (Y) in a developing device holder 29 to form a yellow-colored developer image on the surface of the drum 4. Thus, the drum 4 is a support element of image to load a developed image (toner image).

[0092] The second PM process cartridge accommodates a magenta developer (M) in the developing device holder 29 to form a magenta-colored developer image on the surface of the drum 4.

[0093] The third PC process cartridge accommodates a cyan developer (C) in the developing device holder 29 to form a cyan color developer image on the surface of the drum 4.

[0094] The fourth PK process cartridge accommodates a black developer (K) in the developing device holder 29 to form a black color developer image on the surface of the drum 4.

[0095] Above the first to fourth P process cartridges (PY, PM, PC, PK), an LB laser scanning unit is provided as an exposure device. The LB laser scanning unit emits a laser beam according to the image information. The laser beam Z is scanned onto the surface of the drum 4 through an exposure window 10 of the cartridge P.

[0096] Below the first to fourth P cartridges (PY, PM, PC, PK), an intermediate transfer belt unit 11 is provided as a transfer element. The intermediate transfer belt unit 11 includes a drive roller 13, tension rollers 14 and 15, around which a transfer belt 12 having flexibility extends.

[0097] The drum 4 of each of the first to fourth cartridges P (PY, PM, PC, PK) comes into contact, in the lower surface part, with an upper surface of the transfer belt 12. The contact part is a primary transfer part. Within the transfer belt 12, a primary transfer roller 16 is provided opposite the drum 4.

[0098] Furthermore, a secondary transfer roller 17 is provided in a position opposite the tension roller 14 with the transfer belt 12 interposed between them. The contact part between the transfer belt 12 and the secondary transfer roller 17 is a secondary transfer part.

[0099] Below the intermediate transfer belt unit 11, a feed unit 18 is provided. The feed unit 18 includes a sheet feed tray 19 that accommodates a stack of recording materials S, and a sheet feed roller. 20 sheets.

[0100] Below an upper left part in the main assembly 2 of the apparatus in Figure 2, a clamping unit 21 and a discharge unit 22 are provided. An upper surface of the main assembly 2 of the apparatus functions as a discharge tray 23.

[0101] The recording material S having a developer image transferred thereto is subjected to a clamping operation by a clamping device provided in the clamping unit 21 and thereafter is discharged into the discharge tray 23.

[0102] The cartridge P can be detachably mounted to the main assembly 2 of the apparatus via a pullable cartridge tray 60. Part (a) of Figure 3 shows a state in which the cartridge tray 60 and the P cartridges are pulled from the main set 2 of the device.

[Image formation operation]

[0103] Operations for forming a four-color image will be described.

[0104] Drums 4 of the first to fourth P cartridges (PY, PM, PC, PK) are rotated at a predetermined speed (counterclockwise direction in Figure 2, a direction indicated by arrow D in Figure 4). The transfer belt 12 is also rotated at a speed corresponding to the speed of the drum 4 co-directionally with the rotation of the drums (the direction indicated by an arrow C in Figure 2). Additionally, the LB laser scanning unit is activated. In synchronization with the drive of the LB scanning unit, the surfaces of the drums 4 are charged by the charging rollers 5 to a uniformly predetermined polarity and potential. The LB laser scanning unit scans and exposes the surfaces of the drums 4 with the Z laser beams according to the respective off-color image signal. Therefore, electrostatic latent images are formed on the surfaces of the drums 4 according to the corresponding color image signal respectively. Electrostatic latent images are developed by respective developing rollers 6 rotated at a predetermined speed (clockwise in Figure 2, the direction indicated by an arrow E in Figure 4). The developing roller 6 is a developer support element for loading developer (toner) to develop a latent image in the drum 4.

[0105] Through such an electrophotographic image forming process operation, a yellow color developer image corresponding to the yellow component of the four-color image is formed in the drum 4 of the first PY cartridge. Then the developer image is transferred (primary transfer) to the transfer belt 12.

[0106] Similarly, a magenta developer image corresponding to the magenta component of the four-color image is formed in drum 4 of the second PM cartridge. The developer image is transferred (primary transfer) superimposed on the yellow color developer image already transferred to the transfer belt 12.

[0107] Similarly, a cyan developer image corresponding to the cyan component of the four-color image is formed in drum 4 of the third PC cartridge. Then, the developer image is transferred (primary transfer) superimposed on the yellow and magenta developer images already transferred to the transfer belt 12.

[0108] Likewise, a black developer image corresponding to the black component of the four-color image is formed in drum 4 of the fourth PK cartridge. Then, the developer image is transferred (primary transfer) superimposed on the yellow, magenta and cyan developer images already transferred to the transfer belt 12.

[0109] In this way, a (four) color image comprising yellow color, magenta color, cyan color and black color is formed on the transfer belt 12 (unfixed developer image).

[0110] On the other hand, a recording material S is selected and fed at a predetermined control time. The recording material S is introduced at the predetermined control time to the secondary transfer part which is the contact part between the secondary transfer roller 17 and the transfer belt 12. The recording material S is introduced at the predetermined control time to the secondary transfer part which is the contact part between the secondary transfer roller 17 and the transfer belt 12. Thereby, the superimposed four-color developer image is all transferred together sequentially to the surface of the recording material S of the transfer belt 12 while the recording material S is fed to the secondary transfer part.

[General arrangement of process cartridge]

[0111] The structure of the process cartridge for electrophotographic image formation will be described. In this embodiment, the first to fourth P cartridges (PY, PM, PC, PK) have similar electrophotographic image formation process mechanisms, although the colors and/or loaded quantities of developers accommodated therein are different.

[0112] The cartridge P is provided with the drum 4 as the photosensitive element, and the process device actuable on the drum 4. The process device includes the loading roller 5 as the loading device for loading the drum 4, a roller developing device 6 as the developing device for developing the latent image formed in the drum 4, a cleaning blade 7 as the cleaning device for removing a residual developer remaining on the surface of the drum 4, and so on. The P cartridge is divided into the drum unit 8 and the developing unit 9.

[Drum unit structure]

[0113] As illustrated in Figures 4, 5 and 6, the drum unit 8 comprises the drum 4 as the photosensitive element, the loading roller 5, the cleaning blade 7, a cleaning container 26 as a photosensitive element holder , a residual developer accommodation part 27, cartridge cover elements (a cartridge cover element 24 on the drive side, and a cartridge cover element 25 on the non-drive side in Figures 5 and 6). The photosensitive element holder in a broad sense comprises the cleaning container 26 which is the photosensitive element holder in a narrow sense, and the residual developer accommodation part 27, the cartridge cover element on the drive side 24, the cartridge cover element on the non-drive side 25 as well (this applies to the embodiments described below). The photosensitive element support is a support for rotatably supporting the photosensitive drum 4. When the cartridge P is mounted to the main assembly 2 of the apparatus, the photosensitive element holder is attached to the main assembly 2 of the apparatus.

[0114] The drum 4 is rotatably supported by the cartridge cover elements 24 and 25 provided on the longitudinal opposite end parts of the cartridge P. Here, an axial direction of the drum 4 is the longitudinal direction.

[0115] Cartridge cover elements 24 and 25 are attached to the cleaning container 26 at opposite longitudinal end portions of the cleaning container 26.

[0116] As shown in Figure 5, a coupling element or a drive input part (photosensitive element drive transmission part) 4a for transmitting a drive force to the drum 4 is provided in a longitudinal end part of the drum 4. Part (b) of Figure 3 is a perspective view of the main assembly 2 of the apparatus, in which the cartridge tray 60 and cartridge P are not shown. The coupling elements 4a of the P cartridges (PY, PM, PC, PK) are engaged with the drum drive force output elements 61 (61Y, 61M, 61C, 61K) as drive transmission elements on the assembly side main assembly of the apparatus 2 shown in part (b) of Figure 3 so that the driving force of a drive motor (not shown) of the main assembly of the apparatus is transmitted to the drums 4.

[0117] The loading roller 5 is supported by the cleaning container 26 and is contacted with the drum 4 so as to be actuated in this way.

[0118] The cleaning blade 7 is supported by the cleaning container 26 so as to contact the circumferential surface of the drum 4 at a predetermined impulse.

[0119] An untransferred residual developer removed from the peripheral surface of the drum 4 by the cleaning device 7 is accommodated in the residual developer accommodation part 27 in the cleaning container 26.

[0120] Furthermore, the cartridge cover element on the drive side 24 and the cartridge cover element on the non-drive side 25 are provided with support parts 24a, 25a as a sliding part for rotatably supporting the developing unit. 9 (Figure 6). [Development unit structure]

[0121] As shown in Figures 1 and 8, the developing unit 9 comprises the developing roller 6, a developing blade 31, the developing device support 29, a rolling element 45, a developing device support element revelation 32 and so on. The developing device support in a broad sense comprises the rolling element 45 and the developing device cover element 32 and so on, as well as the developing device support 29 (this applies to the embodiments that will be described Next). The developing device support is a support that rotatably supports the developing roller. When the cartridge P is mounted in the main assembly 2 of the apparatus, the developing device support 29 is movable relative to the main assembly 2 of the apparatus.

[0122] The cartridge holder (cartridge holder P) in a broad sense comprises the photosensitive element holder in the broad sense described above and the developing device holder in the broad sense described above (the same applies to the embodiments that will be described below).

[0123] The developing device support 29 includes the developer accommodation part 49 (Figure 4) accommodating the developer to be supplied to the developing roller 6, and the developing blade 31 for regulating a layer thickness of the developer on the surface peripheral of the development roller 6.

[0124] Furthermore, as shown in Figure 1, the rolling element 45 is fixed to a longitudinal end part of the developing device support 29. The rolling element 45 rotatably supports the developing roller 6. The roller developing roller 6 is provided with a developing roller gear 69 as a developing roller drive transmission element in a longitudinal end part. The developing roller gear 69 is an element (gear) for transmitting the driving force to the developing roller 6, and its outer periphery is formed into a gear part for receiving the driving force.

[0125] The rolling element 45 also rotatably supports the drive transmission element on the cartridge side (drive input element) 74 to transmit the drive force to the developing roller gear 69. The drive transmission element on the cartridge side (drive input element) 74 is provided in an end part with a drive input part 74b. The drive input part 74b is capable of coupling with a drive output element of the developing device 62 (62Y, 62M, 62C, 62K) as the drive transmission element on the main assembly side of the main assembly 2 shown in part (b) of Figure 3. That is, by the coupling engagement between the drive transmission element on the cartridge side and the drive output element of the developing device, the drive force is transmitted from the drive motor (not shown) provided in the main set 2 for the cartridge. This will be described in detail below.

[0126] The developing device cover element 32 is fixed to an exterior of the rolling element 45 with respect to the longitudinal direction of the cartridge P. The developing device cover element 32 is a part of the developing roller gear 69 , the drive transmission element on the cartridge side 74 and so on.

[Assembling the drum unit and developing unit]

[0127] Figures 5 and 6 show the connection between the developing unit 9 and the drum unit 8. On one side of the longitudinal end part of the cartridge P, an outer circumference 32a of a cylindrical part 32b of the cover element of the developing device 32 is mounted on the supporting part 24a of the cartridge cover element on the drive side 24. Furthermore, on the other side of the longitudinal end part of the cartridge P, a projecting part 29b projected from the developing device support disclosure 29 is mounted in a support hole portion 25a of the cartridge cover member on the non-drive side. Therefore, the developing unit 9 is rotatably supported relative to the drum unit 8. Here, a center of rotation (axis of rotation) of the developing unit 9 relative to the drum unit is called “center of rotation (axis). of rotation) The rotation axis X is an axis connecting the center of the support hole part 24a and the center of the support hole part 25a. The axis of rotation X is substantially parallel with the axes of rotation of the drum 4 and the developing roller 6.

[Contact between the developing roller and the drum]

[0128] As shown in Figures 4, 5 and 6, the developing unit 9 is driven by a thrust spring 95 which is an elastic element as a thrust element, so that the developing roller 6 is brought into contact with the drum 4 around the axis of rotation arrow H around the rotation axis X.

[0129] Thrust spring 95 applies thrust force to propel the developing roller 6 towards the drum 4 for the photosensitive element support and the developing device support. With this, the developing roller 6 is placed in contact with the drum 4 at a predetermined pressure. The position of the developing unit 9 relative to the drum unit 8 at this time is a contact position.

[0130] When the developing unit 9 is moved in the direction opposite to the direction of the arrow G against the pushing force of the pushing spring 95, the developing roller 6 is spaced from the drum 4. The position of the developing unit 9 at this time it is a spacing position. In this way, the developing roller 6 is movable towards and away from the drum 4.

[Spacing between the developing roller and the drum]

[0131] Figure 7 is a schematic side view of the cartridge P as viewed along the axis of rotation of the developing roller 6 on the drive side. In this figure, some parts are omitted for better illustration. When the cartridge P is mounted in the main assembly 2, the drum unit 8 is positioned in place in the main assembly 2 of the apparatus.

[0132] In this embodiment, an impulse force receiving part (spacing force receiving part) 45a is provided in the bearing element 45. The impulse force receiving part 45a can be provided in any part of the cartridge P (developing device holder, for example) in place of the bearing element 45. The impulse force receiving part 45a is engageable with a spacing force impulse element (the impulse element on the side of the main assembly) as the spacing force impulse element as the main assembly side impulse element provided in the main assembly 2. The spacing force impulse element 80 as the main assembly side impulse element receives the driving force from of a motor (not shown) and is movable along a rail 81 in the directions indicated by arrows F1 and F2.

[0133] The spacing operation between the developing roller and the photosensitive element (drum) will be described.

[0134] Part (a) of Figure 7 illustrates the state in which the drum 4 and the developing roller 6 are placed in contact with each other. At this time, there is a space d between the impulse force receiving part 45a and the spacing force impulse element 80.

[0135] Part (b) of Figure 7 shows the state in which the spacing force impulse element 80 has moved in the direction of arrow F1 by the distance δ1 from the position shown in part (a) of Figure 7. In this moment, the impulse force receiving part 45a is engaged with the spacing force impulse member 80. As described above, the developing unit 9 is rotatable with respect to the drum unit 8, and in part (b) of the Figure 7, the developing unit 9 rotated by an angle θ1 in the direction of the arrow K around the axis of rotation X. At this time, the developing roller 6 is spaced from the drum 4 by a distance ε1.

[0136] Part (c) of Figure 7 illustrates the state in which the spacing force impulse element 80 has moved by δ2 (> δ1) in the direction of arrow F1 from the position shown in part (a) of Figure 7. Figure 7. The developing unit 9 is rotated by the angle θ2 in the direction of the arrow K around the axis of rotation X. At this moment, the developing roller 6 is spaced from the drum 4 by a distance ε2.

[Position relationship between the developing roller, the driving input element and the impulse force receiving part]

[0137] As shown in parts (a) - (c) of Figure 7, the developing roller 6 is provided between the impulse force receiving part 45a and a drive input element 74, as viewed in the axis direction of rotation of the developing roller on the drive side. That is, as seen in the direction of the axis of rotation of the developing roller, the impulse force receiving part 45a is designed substantially opposite the drive input element 74 with respect to the developing roller 6.

[0138] In more detail, the line connecting a rotation axis 6z of the developing roller 6 and a contact part 45b of the impulse force receiving part 45a to receive the force from the impulse element on the side of the main assembly 80 and the line connecting the rotation axis 6z of the developing roller 6 and the rotation axis of the drive input element 74 intersect at a certain angle. The contact part 45b, the rotation axis 6z of the developing roller 6, and the rotation axis of the drive input element 74 are not coaxial with each other.

[0139] On the other hand, as seen in the direction of the axis of rotation of the developing roller 6, the line connecting the contact part 45b and the axis of rotation of the drive input element 74 can pass through the developing roller 6 Such an arrangement is covered by the expression of arranging the developing roller 6 between the drive input element 74 and the impulse force receiving part 45a.

[0140] In this embodiment, the axis of rotation X of the developing unit 9 with respect to the drum unit is substantially coaxial with the axis of rotation of the drive input element 74.

[0141] Furthermore, between the rotation axis 4z of the photosensitive element 4, the rotation axis of the developing roller 6 is disposed. As seen in the direction of the rotation axis of the developing roller 6 on the drive side, the three lines connecting the rotation axis 4z of the photosensitive element 4, the rotation axis of the drive transmission element on the cartridge side 74 and the contact part 45b form a triangle. Then, the rotation axis 6z of the developing roller 6 is arranged in the triangle.

[0142] As the developing unit 9 rotates relative to the drum unit 8, the position relationships of the cartridge-side drive transmission element 74 and the impulse force receiving part 45a relative to the photosensitive element 4 change . However, in any case, the axis of rotation 6z of the developing roller 6 is disposed between the axis of rotation 4z of the photosensitive element 4, the axis of rotation (X) of the drive transmission element on the side of the cartridge 74 and the contact part 45b.

[0143] By arranging the developing roller 6 between the contact part 45b and the rotation axis is distanced between the contact part 45b and the rotation axis than the distance between the rotation axis 6z of the developing roller 6 and the rotation axis X. With this arrangement, the spacing and contact timing of the developing roller can be controlled with high precision.

[0144] In this embodiment and in the embodiments that will be described below, the distance between the axis of rotation of the drum 4 and the part where the impulse force receiving part 45a contacts the impulse element on the side of the main assembly 80 is in the range of 13 mm - 33 mm. In this embodiment and in the embodiments that will be described below, the distance between the axis of rotation mm.

[0145] In this embodiment, by the rotational movement of the developing unit 9 (developing device support) relative to the drum unit 8 (photosensitive element support), the developing roller 6 is contacted and spaced from the photosensitive element 4. By the simple structure of connecting the developing unit 9 and the drum unit 8 with a shaft, the contact state and the spaced state between the photosensitive element 4 and the developing roller 6 can be easily switched between each other.

[0146] However, the movement of the developing unit 9 (developing device support) is not limited to a rotational movement in this invention. Movement other than rotational movement, such as translation between the developing unit 9 and the drum unit 8, is usable if the distance between the photosensitive element 4 and the developing roller 6 changes by the movement of the developing unit 9 (developing device support) in relation to the drum unit 8 (photosensitive element support).

[Drive transmission to the photosensitive drum]

[0147] The drive transmission for the photosensitive drum 4 will be described.

[0148] As described previously, and as shown in part (b) of Figure 3, the drive input part (photosensitive element drive transmission part) 4a to the photosensitive element, which is the coupling element provided in the end of drum 4 as the photosensitive element is engaged with the drum drive force output element 61 (61Y • 61M • 61C • 61K) of main assembly 2. The photosensitive element drive input portion ( photosensitive element drive transmission) 4a receives drive force from the drive motor (not shown) of the main assembly. With this, the driving force is transmitted from the main assembly to drum 4.

[0149] As illustrated in Figure 1, the photosensitive element drive input part (photosensitive element drive transmission part) 4a which is a coupling element provided at the end part of the photosensitive drum 4 is exposed through an opening 24d of the cartridge cover element on the drive side 24 which is a support provided on the longitudinal end part of the cartridge P. More particularly, the photosensitive element drive input part 4a is projected toward an exterior beyond a plane opening in which the opening 24d of the cartridge cover element on the drive side 24 is provided. Here, the photosensitive element driving input part 4a is not movable in the direction of the rotation axis of the photosensitive element. That is, the photosensitive element drive input part 4a is fixed in relation to the drum 4.

[Drive transmission for developing roller] (Principle of drive connection part and release mechanism)

[0150] With reference to Figures 1 and 8, the structure of the drive connection part will be described. Here, the drive connecting part functions to receive the drive force from the drive output element of the developing device 62 as the drive transmission element on the side of the main assembly provided in the main assembly 2 and to transmit or not transmit the driving force to the developing roller 6.

[0151] The drive connecting part in this embodiment comprises the drive input element 74, a release lever 73, a release cam 72, a spring 70, the developing device cover element 32 and the cover element of cartridge on drive side 24.

[0152] As shown in Figures 1 and 8, the drive input element 74 penetrates the opening 24e of the cartridge cover element on the drive side 24, an opening 32d of the developing device cover element 32, an opening 70a of the spring 70, an opening 72f of the release cam 72 and an opening 73d of the release lever 73. That is, the drive input member 74 is engaged with the developing device drive output member 62. The Drive input 74 is provided in the cartridge P and functions as a drive transmission element on the side of the cartridge to receive drive force from the main assembly 2. The developing device drive output element 62 is provided in the assembly main assembly 2 and functions as a driving force transmission element on the main assembly side to supply the driving force to the cartridge P.

[0153] As shown in Figure 1, the cartridge cover element on the drive side 24 which is the support provided on the longitudinal end part of the cartridge is provided with opening 24e and opening 24d which are through openings. The developing device cover element 32 connected to the cartridge cover element on the drive side 24 is provided with a substantially cylindrical part 32b, and the cylindrical part 32b is provided with the opening 32d which is a through opening.

[0154] The drive input element 74 is provided with a shaft portion 74x, and is provided with the drive input portion 74b at its end portion. The drive input part 74b is in the form of a projection projecting from a free end (end part, end surface) of the drive input element 74 outwards relative to the longitudinal direction of the developing roller. .

[0155] The shaft part 74x is mounted so as to penetrate the opening 73d of the release lever 73, the opening 72f of the release cam, the opening 70a of the spring 70, the opening 32d of the cover element of the developing device 32 and in the opening 24e of the cartridge cover element on the drive side 24.

[0156] The drive input part 74b provided at the free end of the shaft part 74x is exposed externally from the cartridge. By exposing the drive input portion 74b, the drive input portion 74b is visible from the outside of the cartridge P. In this embodiment, as seen on the axis of rotation of the developing roller 6, the drive input portion 74b is visible.

[0157] The drive input part 74b projects outwardly from the cartridge beyond an opening plane of the opening 24e of the cartridge cover element on the drive side 24. Through the coupling engagement between a projection which is the drive input part 74b and a recess 62b of the developing device drive output element 62, the drive force is transmissible from the side of the main assembly to the drive input part 74b. The drive input part 74b is in the form of a substantially triangular prism that is slightly twisted (Figure 1).

[0158] The gear portion 74g provided on the outer peripheral surface of the drive input element 74 is engaged with the developing roller gear 69. The developing roller gear 69 is provided with a gear portion on the outer peripheral surface, and the gear part is engaged with the 74g gear part. The developing roller gear 69 is fixed to the shaft part of the developing roller 6.

[0159] Therefore, the driving force transmitted to the drive input part 74b of the drive transmission element on the cartridge side (drive input element) 74 is transmitted to the developing roller 6 through the gear part 74g of the drive input element 74 and the developing roller gear 69. Among the elements constituting the drive connecting part, the drive input element 74 (drive input part 74b, gear part 74g) and The developing roller gear 69 provides a drive transmission mechanism provided in the P cartridge. The drive transmission mechanism functions to transmit the drive force (rotational force) received from the outside of the P cartridge (drive output element). from the developing device 62 of the main assembly 2) to the developing roller 6.

[0160] In the drive force transmission path through which the drive force received from the outside of the cartridge P is transmitted to the developing roller 6 in the cartridge P, the drive input element 74 (drive input part) drive 74b) is arranged in the most upper position of the drive transmission mechanism in relation to the direction of force transmission. That is, the drive input part 74b is exposed outside the cartridge P and first receives the drive force from the main assembly.

[0161] In other words, the drive input part 74b directly coupled with the recess 62b (rotational force application part, drive output part) of the drive transmission element on the side of the main assembly (power output element) developing device drive 62) provided in the main assembly 2 for directly receiving the driving force from the main assembly 2. More particularly, the driving input part 74b includes a rotational force receiving part 74b3 (Figure 17) for contacting a part defining recess 62b to receive rotational force from recess 62b.

(Structure of drive connection part)

[0162] Referring to Figures 1, 8 and 9, the drive connection part will be described in more detail.

[0163] In the description of this embodiment and the embodiments that will be described below, the outward direction of the cartridge is in the direction indicated by an arrow M in Figure 1. The inward direction of the cartridge is the direction indicated by an arrow N in Figure 1.

[0164] The directions indicated by arrows M and N are along the X axis of rotation. However, even if it is tilted relative to the X axis of rotation, it is considered to be the direction out of the cartridge if it is the direction approaches the direction indicated by arrow M. Similarly, even if it is inclined with respect to the axis of rotation The direction of arrow M is outward in the longitudinal direction of the developing roller 6, and the direction of arrow N is inward in the longitudinal direction of the developing roller 6.

[0165] In the longitudinal end part of the cartridge P, the cartridge cover element on the drive side 24 is provided as a part of the cartridge holder (developing device holder). The shaft of the developing roller is supported by the rolling element 45. Between the cartridge cover element on the drive side 24 and the rolling element 45, there are provided the drive input element 74, the release lever 73, the release cam 72, the spring 70 and the developing device cover element 32 in the order designated by the rolling element 45 towards the cartridge cover element on the drive side 24. That is, the drive input element 74 , the release lever 73, the release cam 72, the spring 70 and the developing device cover element 32 are provided in the order named from inside to outside in the longitudinal direction of the developing roller 6.

[0166] The axes of rotation of these elements are coaxial with the axis of rotation (axis of rotation a dimensional tolerance of the parts, and this applies to the modalities that will be described below. In other words, “coaxial” substantially means “coaxial”.

[0167] Parts (a) and (b) of Figure 9 are schematic cross-sectional views of the drive connection part.

[0168] As described above, a nascent part 74p (inner surface of the cylindrical part) of the drive input element 74 and the first bearing part 45p (outer surface of the cylindrical part) of the rolling element 45 are engaged with each other. Furthermore, the cylindrical part 74q of the input drive member 74 and the inner circumference 32q of the cover member of the developing device 32 are engaged with each other. That is, the drive input member 74 is rotatably supported by the bearing member 45 and the developing device cover member 32 on each of the opposing end portions.

[0169] Furthermore, the rolling element 45 rotatably supports the developing roller 6. Referring to Figures 1 and 8, the second bearing part 45q (inner surface of the cylindrical part) of the rolling element 45 rotatably supports the shaft 6a of the developing roller 6. The developing roller gear 69 is engaged with the shaft portion 6a of the developing roller 6. As described above, the outer peripheral surface of the drive input element 74 is formed into a gear 74g engaged with the developing roller gear 69. Therefore, the rotational force can be transmitted from the drive input element 74 to the developing roller 6 through the developing roller gear 69.

[0170] Furthermore, the centers of the first rolling part 45p (outer surface of the cylindrical part) of the rolling element 45 and the inner circumference 32q of the developing device cover element 32 are coaxial with the axis of rotation X of the unit. development unit 9. Thus, the drive input element 74 is rotatably supported around the axis of rotation X of the development unit 9.

[0171] Outside the developing device cover element 32 in relation to the longitudinal direction of the cartridge P, the cartridge cover element is provided on the drive side 24.

[0172] Part (a) of Figure 9 is a schematic cross-sectional view illustrating an engaged state (coupled state) between the drive input portion 74b of the drive input element 74 and the recess 62b of the drive output element. driving developing device 62 of the main assembly.

[0173] The drive input part 74b is provided on the drive input element 74 and is engaged directly with the recess 62b of the drive output element of the developing device 62 to receive the rotational force of the recess 62b.

[0174] The drive input element 74 receives the drive force (rotational force) through the drive input part 74b to rotate. The recess 62b is the drive output part (rotational force applying part) that directly engages with the drive input part 74b to apply the drive force (rotational force) from the drive input part 74b.

[0175] As shown in part (a) of Figure 9, the drive input portion 74b projects externally from the cartridge beyond the opening plane of the aperture 24e of the cartridge cover element on the drive side 24.

[0176] In the state shown in part (a) of Figure 9, the rotational force is capable of being transmitted to the drive input part 74b from the drive output element of the developing device 62. The position of the developing element driving output of the developing device 62 in this state is called the “second position” of the driving output element of the developing device 62. Between the covering element of the developing device 32 and the release cam 72, the spring is provided 70 which is an elastic element as a thrust element for driving the release cam 72 in the direction indicated by arrow N.

[0177] Part (b) of Figure 9 is a schematic cross-sectional view of the state in which the drive input part 74b is decoupled from the recess 62b of the developing device drive output element 62. The release cam 72 it is movable in the direction indicated by arrow M (outside the cartridge) against the impulse force of spring 70, being driven by the release lever 73 which is a push mechanism. By moving the release cam 72 in the direction of arrow M, the developing device driving output element 62 is driven to move in the direction of arrow M to space the developing device driving output element 62 from the part drive input 74b. Therefore, the coupling between the driving input part 74 and the developing device driving output element 62 is broken so that the rotational force is not transmitted from the developing device driving output element 62 to the developing part drive input 74b.

[0178] As shown in part (b) of Figure 9, the position of the developing device drive output element 62 in the state in which the rotational force is not transmitted from the recess 62b of the device drive output element of revelation 62 to the drive input part 74b is called the “first position”. The first position is downstream of the second position with respect to the direction of movement M of the developing device drive output member 62 (retracted from the cartridge P).

[0179] In the first position, the drive input part 74b and the developing device drive output element 62 are preferably not superimposed on each other with respect to the axis of rotation X. However, the end surface of the developing element The drive outlet of the developing device 62 and the end surface of the drive input portion 74b may be substantially in the same plane, and the drive input portion 74b may be slightly overlapped with the end surface of the drive output member. of the developing device 62. In any case, if the driving output element of the developing device 62 has moved in the direction of arrow M to downstream of the second position, and the coupling of the driving input element 74 (part of drive input 74b) with the developing device drive output element 62 (recess 62b) is broken, it is called the first position.

(Release mechanism)

[0180] The drive disconnection mechanism (release mechanism) will be described. The release mechanism breaks the coupling between the drive input portion 74b of the drive input element 74 and the recess 62b of the developing device drive output element 62 to stop transmission of drive from the main assembly 2 to the developing roller 6.

[0181] Figure 10 shows a relationship between the release cam 72, the spring 70 and the cover element of the developing device 32. The release cam (a release element) 72 comprises a cylindrical part (cylindrical part on the side of the release member) 72k which has a substantially cylindrical shape, a disk portion 72g provided on the inner end surface of the cylindrical portion 72k and expanding externally from the cylindrical portion, and a projecting portion 72i projected from the disk portion 72g . In this embodiment, the projected part 72i projects into the cartridge (direction of arrow N) along the axis of rotation of the developing roller. The developing device cover element 32 is provided with a bearing surface 32e having the opening 32d. The cylindrical part 72k of the release cam 72 penetrates the opening 70a of the spring 70 and is supported so as to slide relative to the opening 32d of the cover member of the developing device 32 in the direction along the axis of rotation X. In other words , the release cam 72 is movable substantially parallel with the axis of rotation of the developing roller 6 with respect to the covering element of the developing device 32.

[0182] Spring 70 is provided between the disc part 72g of the release cam 72 and the abutment surface 32e of the cover member of the developing device 32. The disc part 72g is a part to be driven (receiving part of elastic force) driven by the spring 70. Through the disc part 72g receiving an elastic force from the spring 70, the release cam 72 is driven towards the cartridge P in the direction indicated by the arrow N (to an internal position in the part (the ) of Figure 9, which will be described below). The disc part 72g functions as a force receiving part (a second force receiving part on the release element side, a force receiving part inward).

[0183] The centers of the cylindrical part 72k of the release cam 72 and the opening 32d of the cover element of the developing device 32 are on the same axis.

[0184] The cover element of the developing device 32 is provided with a guide 32h as a guiding part, and the release cam 72 is provided with a guide groove 72h as a part to be guided. Guide 32h and guide groove 72h are extended in parallel with the axial direction. The guide 32h of the cover member of the developing device 32 is engaged with the guide groove 72h of the release cam 72. By engagement between the guide 32h and the guide groove 72h, the release cam 72 is able to move (slide) only in the direction parallel to the axis of rotation X (arrows M and N) in relation to the covering element of the developing device 32.

[0185] It is not necessary for both the guide 32h and the guide groove 72 to be parallel with the rotation axis X, only one of them (in contact with each other) can be parallel to the rotation axis can be moved in parallel with the X axis of rotation.

[0186] It is not absolutely necessary for the release cam 72 to move in parallel with the axis of rotation X, and the release cam 72 may move in an inclined direction relative to the axis of rotation X.

[0187] Figure 11 shows the structures of the release lever 73 and the release cam 72.

[0188] The release cam 72 as the decoupling element is provided with a contact part (inclined surface, contact surface) 72a. The contact part 72a functions as a force receiving part (first force receiving part on the release member side) to receive the force produced by the main assembly 2 through the release lever 73. The release cam 72 is capable of of driving the drive output element 62 by the force received by the contact part 72a, as will be described in detail below.

[0189] The release lever 73 is a rotating element of substantially ring configuration that is rotatable with respect to the developing device support (rolling element 45, developing device cover element 32) and the releasing cam 72. The release lever 73 is an operating element for moving the release cam 72 by acting on the release cam 72.

[0190] The release lever 73 is provided with a contact part (inclined surface, contact surface) 73a as an operating part (thrust part on the rotating element side, lateral push part on the operating element side) which acts on the contact part 72a of the release cam 72.

[0191] The contact part 73a of the release lever 73 and the contact part 72a of the release cam 72 can be brought into contact.

[0192] In Figure 11, the numbers of the contact parts 73a of the release lever 73 and the contact parts 72a of the release cam 72 are two, respectively, but the numbers are not restricted to two. For example, numbers can be one, three, or more, respectively.

[Drive Disconnect Operation]

[0193] Referring to Figure 7 and Figures 12-15, the operation of the drive connecting part when its state changes from the state in which the developing roller 6 and the drum 4 come into contact with each other to the state where they are spaced apart will be described. For better illustration, Figures 12 - 15 omit some parts, and the release lever and release cam are shown partially schematically. In the figure, arrow M along the X axis of rotation indicates the direction out of the cartridge and arrow N along the axis of rotation X indicates the direction into the cartridge.

[State 1]

[0194] As shown in part (a) of Figure 7, the spacing force impulse element 80 and the impulse force receiving part 45a of the bearing element 45 are spaced apart by a space d. In this case, the drum 4 and the developing roller 6 come into contact with each other. This state is called “state 1” of the spacing force driving element 80.

[0195] The state of the driving connection part is as shown in Figure 13. In part (a) of Figure 13, a pair of the driving input element 74 and the developing device driving output element 62 and the pair of release cam 72 and release lever 73 are shown separately and schematically. Part (b) of Figure 13 is a perspective view illustrating a structure of the drive connecting part. Between the contact part 72a of the release cam 72 and the contact part 73a of the release lever 73 there is a space e. At this time, the drive input part 74b of the drive input element 74 and the recess 62b of the developing device drive output element 62 are engaged with each other by an engagement amount q, so that the drive transmission can be carried out.

[0196] As described above, the drive input element 74 is engaged with the developing roller gear 69. Therefore, the drive force received by the drive input element 74 from the main assembly 2 is transmitted to the gear of developing roller 69 to rotate developing roller 6. This state is called “developing and drive transmission contact state”. Furthermore, the position of the driving output element of the developing device 62 is the second position described above. In the second position of the drive output member of the developing device 62, the recess (rotational force application part) 62b is in coupling engagement with the drive input part 74b such that drive transmission can be effected. (drive transmission position). The position of the drive input element 74 (drive input part 74b) at this time is called the second position of the drive input element 74 (drive input part 74b).

[State 2]

[0197] Part (a) of Figure 14 and part (b) of Figure 14 illustrate the drive connecting part at the time when the thrust element on the main assembly side of the spacing force thrust element 80 is moved from the developing contact drive transmission position by δ1 in the direction indicated by an arrow F1 in the figure as shown in part (b) of Figure 7.

[0198] As illustrated in part (b) of Figure 7, when the spacing force impulse element 80 moves by δ1, the impulse force receiving part 45a receives the force from the spacing force impulse element. spacing 80, whereby the developing unit 9 is rotated by an angle θ1 in the direction indicated by an arrow K about the axis of rotation X. As a result, the developing roller 6 is spaced from the drum 4 by the distance ε1. The release cam 72 and the developing device cover element 32 of the developing unit 9 rotate in interrelation with the rotation of the developing unit 9 by angle θ1 in the direction indicated by an arrow K.

[0199] On the other hand, when the cartridge P is mounted in the main assembly 2, the drum unit 8, the cartridge cover element on the drive side 24 and the cartridge cover element on the non-drive side 25 are fixed in place relative to the main set 2.

[0200] As shown in Figure 12, the release lever 73 of the developing unit 9 is provided with the force receiving part (projected part, part to be engaged) 73b designed from a ring configuration part of the lever release part 73 in a direction of a line perpendicular to the axis of rotation release lever 73 is limited. Even though the rotation of the release lever 73 is limited, the developing unit 9 is capable of rotating because the covering element of the developing device 32 is provided with an opening 32c.

[0201] The contact part 72a of the release cam 72 rotates in the direction indicated by arrow K (part (b) of Figure 7) in interrelation with the rotation of the development unit 9 with respect to the contact part 73a of the lever release 73 which is limited in its rotation. As a result, the contact part 72a of the release cam 72 begins to contact the contact part 73a of the release lever 73. At this time, the drive input element 74 and the device drive output element of development 62 keep in contact with each other (part (a) of Figure 14).

[0202] Then, the driving force introduced into the drive input element 74 from the main assembly 2 is being transmitted to the developing roller 6 through the developing roller gear 69. The state of these parts is a “state of separation of developing device and drive transmission”. The position of the driving output element of the developing device 62 at this time is also the second position.

[State 3]

[0203] Part (a) of Figure 15 and part (b) of Figure 15 illustrate the drive connecting part at the moment when the thrust element on the main assembly side of the spacing force thrust element 80 moves moves from the separation drive transmission position of the developing device in the direction indicated by the arrow F1 in the Figure by δ2 as shown in part (c) of Figure 7. As shown in part (c) of Figure 7, through the thrust element of spacing force 80 moving by δ2, the developing unit 9 is rotated by an angle θ2 (> θ1) by the impulse force receiving part 45a which receives the force from the spacing force impulse element 80 .

[0204] In interrelation with the rotation of the developing unit 9 through the angle θ2 by the spacing force push element 80, the release cam 72 and the developing device support (developing device support 29, element bearing element 45 and developing device cover element 32) are rotated in the direction indicated by arrow K in the figure. On the other hand, the state of the release lever 73 remains unchanged, in a similar way as above, due to engagement with the engaging part 24s (Figure 12) provided on the cartridge cover element on the drive side 24. That is, the release lever 73 rotates in the direction indicated by arrow H (part (c) of Figure 7) relative to the developing device holder and release cam 72.

[0205] At this time, the contact part 72a of the release cam 72 receives a reaction force from the contact part 73a of the release lever 73. That is, the contact part (thrust part on the side of the rotating element ) 73a of the release lever 73 drives the contact part 72a of the release cam 72 in the direction indicated by arrow M. The contact part 72a is the external force receiving part (first force receiving part on the side of the release element). release) to receive the externally directed force of the cartridge P from the contact part 73a.

[0206] Here, as described above, the release cam 72 is capable of sliding movement in the axial direction (directions of arrows M and N) by the guide groove 72h of the release cam 72 engaging with the guide 32h of the cover element of the developing device 32 (Figure 10). Therefore, through the force-receiving contact part 72a, the release cam 72 slides in the direction indicated by the arrow M for a movement distance p relative to the release lever 73.

[0207] Thereby, in interrelation with the movement of the release cam 72 in the direction indicated by an arrow M, the cylindrical part 72k of the release cam 72 overlaps with the drive input part 74b of the input element of drive 74 in the direction of the P. In this embodiment, the drive output element of the developing device 62 moves in parallel with the X axis of rotation.

[0208] In summary, the thrust force supplied by the main assembly 2 is transmitted to the bearing element 45 (thrust force receiving part 45a) of the cartridge P through the spacing force thrust element 80.

[0209] Therefore, the developing unit 9 (developing device support and release cam 72) rotates in the direction indicated by the arrow K by θ2 (part (c) of Figure 7). At this time, the release lever 73 engaged with the cartridge cover element on the drive side 24 is rotated relative to the developing device holder and the release cam 72. Thus, the thrust force received by the receiving part of the thrust force 45a is transmitted to the contact part 72a of the release cam 72 through the contact part 73a of the release lever 73 (Figures 11 and 12).

[0210] The release cam 72 drives the developing device drive output element 62 by the free end (thrust part) of the cylindrical portion 72k to move the developing device driving output element 62 in the direction of arrow M (part (b) of Figure 9, Figure 15), using the force received by the contact part 72a.

[0211] At this time, as shown in Figures 14 and 15, the moving distance p of the developing device drive output element 62 is greater than the amount of engagement q between the drive input element 74 and the output drive element of the developing device 62 and therefore the engagement between the driving input element 74 and the driving output element of the developing device 62 is broken. Although the developing device driving output element 62 of the main assembly 2 continues to rotate, the driving input element 74 stops. As a result, the rotation of the developing roller gear 69 and therefore the rotation of the developing roller 6 stops.

[0212] The state of the parts is called the “reveal device separation and drive disconnection state”. The position of the drive output element 62 at this time is the first position.

[0213] As shown in Figure 15, the position of the release cam 72 at the time when the developing device drive output element 62 is in the first position is the first position of the release cam 72. The first position of the cam release cam 72 is away from the second position of the release cam 72 illustrated in Figure 14 in an outward direction along the axis of the developing roller, and is called the “outer position”. Furthermore, the release cam 72 in the outer position is projected (projected position) outward from the process cartridge compared to the second position of the release cam 72 (Figure 14). In the external position, the release cam 72 drives (thrust position) the drive output member of the developing device 62 by the free end of the cylindrical portion 72k to move it. The outer position is also a coupling release position (connection release position) for releasing (breaking) the coupling between the drive input part 74b of the drive input element 74 and the recess 62b of the drive output element of developing device 62, and is also a blocking position and a non-drive transmission position for disconnecting the drive transmission to the drive input part 74b.

[0214] On the other hand, as shown in Figure 14, the position of the release cam 72 at the time when the developing device drive output element 62 is in the second position is the second position of the release cam 72. In second position of the release cam 72, the release cam 72 is internal (internal position) of the cartridge in the longitudinal direction of the developing roller compared to the external position shown in Figure 15. In the internal position, the release cam 72 is retracted (retracted position) into the P cartridge from the external position. The internal position of the release cam 72 is an enabling position to allow coupling between the drive input part 74b and the recess 62b, wherein the developing device drive output member 62 is in the second position. The internal position of the release cam 72 is a drive connection position (drive transmission position) in which the drive transmission path is connected to the drive input portion 74b to enable transmission of the drive thereto.

[0215] In summary, as shown in part (c) of Figure 7, the impulse force receiving part 45a receives the impulse force from the main assembly 2 (spacing force impulse element 80). Using the thrust force, the developing unit 4 (developing device holder) is rotated, and the release cam 72 is moved from the inner position (Figure 14) to the outer position (Figure 15). Thereby, the release cam 72 retracts the drive output element of the developing device 74 in parallel with the axis of rotation X from the second position (Figure 14) to the first position (Figure 15). Therefore, the release cam 72 breaks the coupling between the drive input element 74 (drive input part 74b) and the developing device drive output element 62 (recess 62b) to disconnect the drive transmission.

[0216] By moving the release cam 72 from the outer position to the inner position, the drive output element of the developing device 74 can move from the first position to the second position. Therefore, the drive input part 74b and the developing device drive output element 74 are coupled together to enable transmission of drive to the drive input part 74b. The description will be given in more detail below.

[0217] The release cam 72 is a movable element moved between the internal position and the external position by the sliding movement in the longitudinal direction of the developing roller 6. That is, the release cam 72 is movably supported by the support of the developing device (guide portion 32h of the developing device cover element 32, Figure 10) and the shaft portion 74x (Figure 1) of the drive input element 74. The release cam 72 is alternated between the inward and the external position by the sliding movement with the axis part 74x being in the cylindrical part 72k (Figure 1).

[0218] The release cam 72 is a decoupling element for decoupling the drive input part 74b and the recess 62b from the developing device drive output element 62 by the release cam 72 moving to the outer position and driving the drive output element of the developing device 62.

[0219] A surface 72k1 of the free end of the cylindrical part 72k (part (b) of Figure 15) of the release cam 72 is a thrust part (thrust part on the side of the release member) that can come into contact with the driving output member of the developing device 62 to propel it into the retracted position. That is, the thrust part 72k1 is an annular (ring-like) surface (Figure 14). Thrust portion 72k1 is a surface substantially perpendicular to the X axis of rotation.

[0220] As described above, the movement distance p through which the drive output element of the developing device 62 is moved from the second position to the first position by sliding the release cam 72 is preferably greater than the amount of engagement q between the drive input element 74 and the developing device drive output element 62. That is, in the state that the release cam 72 is in the external position (Figure 15), the thrust part ( The free end of the release cam 72) of the release cam 72 is preferably external in comparison with the free end of the drive input part 74b in the longitudinal direction of the developing roller 6. The free end of the drive input part 74b is at the outer end of the drive input part 74b relative to the longitudinal direction of the developing roller.

[0221] The rotational axis of the developing roller 6 is substantially parallel to the axis of rotation X1. Therefore, in the description in conjunction with Figures 9, 13-15 and 16, the longitudinal direction of the developing roller 4 is parallel to the axis of rotation X, and the outer relative to the longitudinal direction is the side indicated by the arrow M , and the interior is the location indicated by arrow N.

[0222] As shown in part (b) of Figure 9, when the release cam 72 is moved to the outward position, the drive output element of the developing device 62, driven by the release cam 72, retracts into the position more external than the free end of the drive input part 74b in the longitudinal direction of the developing roller, that is, to the first position (coupling release position). The drive input part 74b and the developing device drive output element 62 are out of contact with each other, so that the drive transmission to the drive input part 74b can be safely interrupted.

[0223] With reference to Figure 16, the position relationship between the release cam 72 and the drive input part 74b will be described in detail. Figure 16 shows the release cam 72 and the drive input part 74b projected on a ghost line X1 parallel with the axis of rotation of the developing roller 6. Part (a) of Figure 16 shows the state in which the cam release button 72 is in the internal position. Part (b) of Figure 16 shows the state in which the release cam 72 is in the external position.

[0224] When the release cam 72 is in the external position, at least the free end of the release cam 72 is exposed towards the outside of the cartridge P through the opening 24e of the cover element on the drive side 24 and through the opening 32b of the developing device cover element 32 (Figure 1).

[0225] As shown in part (b) of Figure 16, when the release cam 72 is in the outer position, an area A1 of the drive input part 74b projected on the ghost line X1 is overlapped with an area A2 of the release cam 72 projected onto it. More particularly, the entire area A1 is in area A2 (area A2 contains the entire area A1). A strip A3 where area A1 and area A2 are overlapping each other on ghost line X1 has the same width as area A1.

[0226] By moving the release cam 72 from the inner position to the outer position, that is, by changing the state from that shown in part (a) of Figure 16 to that shown in part (b) of Figure 16, the range A3 raises. That is, the amount of projection of the free end part of the release cam 72 beyond the cover element on the drive side 24 and the cover element of the developing device 32 (Figure 1) increases.

[0227] When the release cam 72 is in the internal position, the area A1 of the drive input part 74b and the area A2 of the release cam 72 do not overlap, as shown in part (a) of Figure 16. In other words, the width of the A3 strip is 0 mm. On the other hand, when the release cam 73 moves to the outer position, the width of the strip A3 becomes equal to the width (height, projection) of the drive input part 74b, which is approximately 2.0 mm in this case. modality, as shown in part (b) of Figure 16.

[0228] When the release cam 72 is in the outward position (part (b) of Figure 16), it is not always necessary for the free end of the release cam 72 (thrust portion of the release cam 72) to be in a position outside the free end of the drive input part 74b in the longitudinal direction of the developing roller. For example, this may be the case where the free end of the release cam 72 and the end surface 74b1 of the drive input portion 74b are substantially in the same plane. Furthermore, at this time, the end surface (free end) of the driving input part 74b and the end surface of the developing device driving output element 62 are substantially in the same plane, and therefore the developing element developing device drive output 62 is not coupled with the drive input part 74b, and the drive transmission is disconnected.

[0229] Furthermore, even if the free end of the drive input portion 74b is slightly overlapped with the drive output element of the developing device 62, drive transmission from the drive input element 74 to the drive input element 74 developing device drive output 62 may be broken, depending on the structure. Such a structure will be described below as a modified example of this embodiment.

[0230] In the foregoing, the description has been made as to the operation of the release mechanism to stop the transmission of drive to the developing roller 6 in interrelation with the rotation of the developing unit 9 in the direction of arrow K. When employing In such a structure, the developing roller 6 can be spaced from the drum 4 while rotating. As a result, the drive transmission for the developing roller 6 can be stopped depending on the spacing distance between the developing roller 6 and the drum 4.

[0231] The release cam 72 and release lever 73 operable on the release cam 72 and so on constitute a part of the release mechanism for breaking the coupling between the recess 62b of the drive output member of the developing device 62 and the drive input part 74b. By the mechanism, the coupling is disconnected, and the drive transmission to the developing roller 6 is stopped.

[Drive connection operation]

[0232] The description will be made as to the operation of the drive connecting part when the state changes from the state in which the developing roller 6 is spaced from the drum 4 to the state in which they are brought into contact with each other. This operation is opposite to the operation of the contact state for the spaced developing device state described previously.

[0233] In the state of the spaced developing device (the developing unit 9 is in the angular position θ2, as shown in part (c) of Figure 7), the connecting part of the drive is in the state that the input element of drive 74 and the developing device driving output element 62 are disconnected from each other, as shown in Figure 15. That is, the developing device driving output element 62 is in the first position.

[0234] When the spacing force impulse element 80 is moved in the direction indicated by an arrow F2 from this state, the force received by the impulse force receiving part 45a from the spacing force impulse element 80 decreases. As a result, the developing unit 9 rotates in the direction of arrow H (opposite the direction K) shown in part (c) of Figure 7 by the thrust force of the thrust spring 95 (Figure 4).

[0235] When the developing unit 9 is rotated in the direction indicated by the arrow H shown in Figure 7, the release lever 73 causes the force receiving part 73b to engage with an engaging part 24t provided on the cover element of the cartridge on the drive side 24. Therefore, the release lever 73 does not rotate in conjunction with the developing unit 9. The release cam 72 that rotates in conjunction with the developing unit 9 rotates relative to the release lever 73. In In other words, the release lever 73 rotates in the direction of arrow K relative to the developing device holder and the release cam 72.

[0236] With rotation of the release lever 73, the contact portion 73a of the release lever 73 begins to retract from the contact portion 72a of the release cam 72. Corresponding to the amount of retraction of the contact portion 73a, the release cam 72 moves in the direction of arrow N by the force of spring 70.

[0237] In the state in which the developing unit 9 is rotated by angle θ1 (the state shown in part (b) of Figure 7 and Figure 14), the release cam 72 & is moved to the internal position by the force of spring impulse 70.

[0238] With separation of the release cam 72 from the developing device drive output element 62 by movement to the internal position, the developing device drive output element 62 is moved to the second position by being driven in the direction of arrow N by the spring (not shown) of the main assembly 2. Then, the drive input element 74 is engaged with the drive output element of the developing device 62, as shown in Figure 14.

[0239] Therefore, the driving force is transmitted from the main assembly 2 to the developing roller 6, thus rotating the developing roller 6. That is, the driving output element of the developing device 62 is in the second position. At this time, the developing roller 6 and the drum 4 are kept spaced apart from each other.

[0240] Furthermore, from this state, the spacing force impulse element 80 is moved in the direction of arrow F2 to separate the spacing force impulse element 80 from the impulse force receiving part 45a, whereby the developing unit 9 gradually rotates in the direction of the arrow H shown in Figure 7 by the force of the impulse spring (Figure 4). As a result, the developing roller 6 and the drum 4 can finally come into contact with each other (part (a) of Figure 7). Also in this state, the drive output element of the developing device 62 is in the second position. In this embodiment, in the state that the developing roller 6 and the drum 4 are in contact with each other, the force received by the spacing force impulse element 80 from the impulse force receiving part 45a is zero, because the impulse force receiving part 45a does not contact the spacing force impulse element 80. However, the impulse force receiving part 45a may contact the spacing force impulse element 80, if the developing roller 6 and the drum 4 are in contact with each other.

[0241] In summary, in the state in which the force received by the impulse force receiving part 45a from the spacing force impulse element 80 is decreased (part (b) of Figure 7) or is zero (part ( c) of Figure 7), the development unit 4 is rotated in the direction of arrow H by the force of the impulse spring 95 (Figure 4). Through the rotation of the development unit 4, the development roller 6 approaches the drum 4 and the release cam 72 moves towards the internal position (Figures 13, 14) using the force of the spring 70. With the movement of the release cam 72 to the inner position, a drive force transmission path from an outside of the cartridge P to the developing roller 6 is established.

[0242] In the foregoing, the operation of transmitting drive to the developing roller 6 in interrelation with the rotation of the developing unit 9 in the direction of arrow H was described with the structure described above, the developing roller 6 is placed in contact with the drum 4 during rotation, and the driving force can be transmitted to the developing roller 6, depending on the spacing distance between the developing roller 6 and the drum 4.

[0243] Cartridge P is provided with the release cam 73 as the actuatable operating element on the release cam 72, and the release cam 72 is moved from the outer position (Figure 15) to the inner position (Figure 14) by the release cam 73 moving (rotating) relative to release cam 72.

[0244] The release lever 73 functions as a switching element to switch the direction of movement of the release cam 72 by changing the direction of movement (direction of rotation) relative to the release cam 72. As previously described, when the lever release cam 73 is moved (rotated) in the direction of arrow H indicated in part (b) of Figure 7 in relation to release cam 72, that is, when release cam 72 is moved in the direction of arrow K in relation to the lever release cam 73, the release lever 73 moves the release cam 72 from the inner position to the outer position. On the other hand, when the release lever 73 moves (rotates) in the direction of arrow K (opposite arrow H) relative to the release cam 72, that is, when the release cam 72 moves in the direction of arrow H relative to the release lever 73, the release lever 73 moves the release cam 72 from the outer position to the inner position.

[0245] The release cam 72 functions as a movable element that moves relative to the drive input element 74 (drive input part 74b) by reciprocating movement of the release cam 72 between the inner position and the outer position.

[0246] The release cam 72 engages (couples) the drive input part 74b with the recess (rotational force application part) 62b and disengages (decouples) them by movement relative to the drive input part 74b. More particularly, the release cam 72 moves relative to the drive input part 74b (rotational force receiving part 74b3) by displacement at least in the longitudinal direction of the developing roller. Through the release cam 72 moving outward in the longitudinal direction relative to the drive input part 74b, the engagement (coupling) between the drive input part 74b and the recess 62b is broken. Through the release cam 72 moving inwardly in the longitudinal direction with respect to the drive input part 74b, engagement between the drive input part 74b and the recess 62b is permitted.

[0247] In this embodiment, the release lever 73 which is the operating element is a rotating element that rotates relative to the release cam 72. However, the operating element is not limited to a rotating element. The operating element may be of another form if it is movable with respect to the release cam 72 and actuatable on the release cam 72 in interrelation with the rotation of the developing unit 9. In this embodiment, the release lever 72 when the element of operation moves the release cam 72 moving in the direction that crosses the axis of rotation X, more particularly, perpendicular to the axis of rotation X.

[0248] When the release cam 72 is in the internal position, the free end of the release cam 72 is in substantially the same position as a rear end 74b2 of the drive input portion 74b relative to the longitudinal direction of the developing roller, as shown in part (a) of Figure 16. At this time, the free end of the release cam 72 does not contact the developing device drive output element 62. Therefore, the drive input part 74b is allowed as being in the second position, and is capable of securely coupling with the developing device drive output element 62. Furthermore, the release cam 72 does not influence the rotation of the developing device drive output element 62.

[0249] The rear end 74b2 of the drive input part 74b is a lower part of the drive input part 74b that is in the form of a projection. The position of the rear end of the drive input part 74b corresponds to the position of the end surface of the drive input element 74 provided with the drive input part 74b.

[0250] Furthermore, the free end of the release cam 72 may be disposed within the rear end 74b2 of the drive input part 74b relative to the longitudinal direction of the developing roller when the release cam 72 is in the internal position. Also in this case, the free end of the release cam 72 does not come into contact with the drive output element of the developing device 62 and therefore the same effects can be provided.

[0251] On the other hand, the free end of the release cam 72 may be disposed slightly external to the rear end 74b2 of the drive input part 74b with respect to the longitudinal direction of the developing roller when the release cam 72 is in the internal position. . That is, the free end of the release cam 72 may come into contact with the drive output element of the developing device 62 if the drive input portion 74b is coupled with the recess 62b of the drive output element of the developing device. disclosure 62 to effect drive transmission. At this time, also when the release cam 72 is in the internal position, area A1 and area A2 are partially overlapped on the ghost line X1 shown in part (a) of Figure 16.

[0252] As described previously, with the structure described above, the switching between the drive disconnection and the drive transmission for the developing roller 6 can be definitively determined based on the rotation angle of the developing unit 9.

[0253] In the foregoing, the contact part 72a of the release cam 72 and the contact part 73a of the release lever 73 make face-to-face contact, but this is not limiting to the present invention. For example, the contact may be in the form of a face-to-line contact, a face-to-point contact, a line-to-line contact, or a line-to-point contact.

[0254] Additionally, the release cam 72 has been described as being movable substantially in parallel with the X axis of rotation, but may be movable in a direction inclined with respect to the X axis of rotation. release cam 72 is not limited to a particular direction if the drive output element of the developing device 62 can be driven.

[0255] In this embodiment, the release cam 72 is constituted in such a way that, even if the direction of movement of the release cam 72 is inclined with respect to the X axis of rotation, the vector along the direction of movement has at least a component in parallel with the rotation axis X. That is, even when the direction of movement of the release cam 72 is not parallel to the rotation axis X (longitudinal direction of the development roller).

[0256] Furthermore, in this embodiment, the elastic element (spring 70) actuable on the release cam 72 is a push spring for pushing the release cam 72 into the cartridge P (toward the internal position) (Figure 10) . However, the elastic element may be a tension spring that pulls the release cam 72 toward the inward position, changing the position of the elastic element. Furthermore, spring 70 has been described as a helical spring, but it may be another elastic element such as a leaf spring.

[0257] The release cam 72 is disposed adjacent to the drive input element 74 (Figure 1), so that it can drive the drive output element 62 with certainty. In this embodiment, a diameter of the drive output element 62 is approximately 15 mm. Accordingly, the release cam 72 is capable of driving the drive output member 62 if at least a portion of the release cam 72 is disposed within the range of approximately 7.5 mm (radius) from the axis of rotation ( center of rotation X) of the drive input element 74 (drive input part 74b).

[Modified example]

[0258] Figure 17 illustrates a modified example that is different from the embodiment described above in the movement distance p at the moment the release cam 72 moves from the inner position to the outer position. In the above embodiment, the movement distance p of the release cam 72 is greater than the projection amount of the drive input portion 74b (amount of engagement q of approximately 2.0 mm between the drive input portion 74b and the developing device drive output element 62). In this modified example, the movement distance p of the release cam 72 is less than the projection amount (engagement amount q) of the drive input part 74b. As a result, even when the release cam 72 is in the external position, the free end of the drive output member of the developing device 72 is disposed within the end surface 74b1 of the drive input portion 74b with respect to the longitudinal direction. of the developing roller. Even when the release cam 72 is in the external position, a portion on the free end side of the drive input portion 74b is overlapped with the drive output member of the developing device 62.

[0259] With such a structure, the drive transmission from the drive output element of the developing device 62 to the drive input part 74b can be interrupted. This is because, on the free end side of the driving input part 74b, an inclined part 74b3 is provided, and when the developing device driving output element 62 comes into contact with only the inclined part 74b3, the developing element developing device drive output 62 rotates at idle.

[0260] The inclined part 74b3 is provided adjacent to the end surface 74b1 of the drive input part 74b and is in the form of a chamfered part of the corner of the drive input part 74b.

[0261] Furthermore, adjacent to the base part (rear part, bottom part) 74b2 of the drive input part 74b, a rotational force receiving part 74b4 is provided adjacent to which the rotational force receiving part 74b4 and the inclined part 74b3 are arranged.

[0262] The rear end 74b2 of the drive input part 74 corresponds to the rear end of the rotational force receiving part 74b4. A boundary part between the rotational force receiving part 74b4 and the inclined part 74b3 corresponds to the free end of the rotational force receiving part 74b4.

[0263] The rotational force receiving part 74b4 is the part (surface) that contacts the recess 62b to directly receive the driving force from the recess 62b when the drive input part 74b is coupled with the recess 62b of the developing device drive output element 62. The rotational force receiving part 74b4 has a width (dimension occupied by the developing roller in the longitudinal direction) of approximately 1.7 mm.

[0264] The inclined part 74b3 is inclined with respect to the rotation axis of the drive input part 74b and the rotational force receiving part 74b4, and the angle formed between the rotation axis than the angle formed between the axis of rotation X and the rotational force receiving part 74b4. The inclined surface 74b3 is a smooth curved surface (with a radius of curvature of approximately 0.3 mm) connecting the free end of the rotational force receiving part 74b4 and the end surface 74b1, but may be in the form of a flat surface . A width of the inclined surface 74b3 (width occupied by the developing roller in the longitudinal direction) is approximately 0.3 mm.

[0265] In this embodiment, the movement distance p of the release cam 72 is between 1.7 mm and 2.0 mm. When the release cam 72 is in the outward position, the free end of the release cam 72 (thrust part of the release cam 72) is in the same position as the free end of the rotational force receiving part 74b4 or in the outward position.

[0266] On the other hand, the free end of the release cam 72 is within the end surface 74b1 of the drive input part 74b relative to the longitudinal direction of the developing roller. That is, the free end of the release cam 72 is partially overlapped with the inclined part 74b3 of the drive input part 74b with respect to the longitudinal direction of the developing roller.

[0267] In this modified example, the drive input part 74b and the developing device drive output element 72 are designed on a phantom line (parallel to the axis of the developing roller) X1. Then, when the drive input part 74b is in the external position, an area A1 of the drive input part 74b and an area A2 of the release cam are partially overlapped with each other on the ghost line X1, but not the entire area A1 is within area A2. That is, an entire area A11 of area A1 corresponding to the rotational force receiving part 74b4 overlaps with a part A121 of area A12 corresponding to the inclined part 74b3. However, the remaining part A122 of area A12 corresponding to the inclined part 74b3 is outside area A2 in the longitudinal direction.

[0268] Therefore, also when the release cam 72 is in the external position, the inclined part 74b3 of the drive input part 74b is in contact with the drive output element of the developing device 62. However, once Since the inclined part 74b3 is inclined with respect to the axis of rotation

[0269] The drive input element 74 is supported with play in the longitudinal direction of the developing roller 6. Therefore, when the inclined portion 74b3 receives force from the drive output element of the developing device 62, the drive input element 74 tends to retract in the direction of arrow N by the force received. Due to the tendency of the driving input part 74b to separate from the developing device driving output element 62, coupling between the driving input part 74b and the developing device driving output element 62 is prevented. although they are in contact with each other. The inclined portion 74b3 does not engage with the recess 62b of the drive output member of the developing device 62. Transmission of drive force to the drive input portion 74b is limited.

[0270] As a result, even if the developing device driving output element 62 is rotated, the driving input part 74b does not rotate. Or, even if the drive input part 74b is rotated, the rotation frequency (rotation speed) is very limited.

[0271] By movement in the direction of separation between the drive input element 74 and the developing device drive output element 62, the drive transmission is interrupted (decoupled). Briefly, the drive input part 74b is provided with a part (rotational force receiving part 74b4) for transmitting the drive force from the recess 62b of the drive output element of the developing device 62 and a part ( inclined part 74b3) so as not to transmit it.

[0272] In this modified example, when the release cam 72 is in the outward position, it is projected beyond the free end of the rotational force receiving portion 74b4, through which the contact between the rotational force receiving portion 74b4 and the developing device drive output element 62 is prevented. Therefore, even if contact between the inclined part 74b3 of the driving input part 74b and the developing device driving output element 62 is allowed, the driving transmission is interrupted.

[0273] At this time, when the release cam 72 and the rotational force receiving part 74b1 are projected onto the ghost line each other on the X1 ghost line. By movement of the release cam 72 from the inner position (Figure 14) to the outer position (Figure 17), the range in which the area A2 of the release cam 72 and the area A11 of the rotational force receiving portion 74b4 in ghost line X1 increases.

[0274] It would be sufficient if the free end of the release cam 72 was in substantially the same position as the free end of the rotational force receiving part 74b4 (boundary between the rotational force receiving part 74b and the inclined part 74b3) or at the position outside of the same in relation to the longitudinal direction.

[0275] In this modified example, the rotational force receiving part 74b4 has a width of approximately 1.7 mm. Therefore, the release cam 72 moving to the free end of the release cam 72 extends beyond the rear end 74b2 by at least 1.7 mm outwardly in the longitudinal direction.

[0276] However, the width of the rotational force receiving part 74b4 can be made smaller than 1.7 mm, in which case the movement distance of the release cam 72 can be further reduced.

[0277] In this modified example, the driving input part 74b is provided with a part (inclined part 74b3) that cannot transmit the driving force, but it is considered that the developing device driving output element 62 is provided with a part that does not transmit the driving force. In this case, the drive transmission may be interrupted if, when the release cam 72 causes the drive output element of the developing device 62 to retract (when the release cam 72 is in the external position), the drive input 74b contacts only the drive output element of the developing device 62.

[0278] This modified example was described as a modification of Modality 1, but it is also applicable to the other modalities that will be described below.

[0279] Figure 18 shows another modified example. Part (a) of Figure 18 is a sectional view in which the release cam 72 is in the external position, and part (b) of Figure 18 is a perspective view.

[0280] With this previously described structure the surface (end surface) 72k1 of the free end of the cylindrical part 72k of the release cam 72 functions as a thrust part to drive the drive output element of the developing device 62 (Figure 15 ). That is, the thrust part for driving the driving output element of the developing device 62 has an annular (ring-like) shape.

[0281] In this modified example, three projections 72k2 are provided on the free end side of the cylindrical part 72k as the thrust part. These projections 72k2 are effective to drive the revealing drive output element 62 to make it retracted to the first position (coupling release position). In other words, a plurality of thrust parts are provided for driving the driving output element of the developing device 62. The number of the thrust parts is not limited to three. It could be two, four or more.

[0282] When employing a plurality of thrust parts, they are preferably arranged at regular intervals with respect to the axis of rotation, since the drive output element of the developing device 62 can be stably driven and retracted by the plurality of the impulse parts. In this embodiment, two adjacent of the three 72k2 projections are all equal (at regular intervals). When the number of 72k2 projections is two, the 72k2 projections are provided in diametrically opposite positions.

[0283] Furthermore, the configurations and sizes of the projections 72k2 are the same, so that the projection amounts of the projections 72k2 (the positions of the free ends of the projection 72k2 relative to the longitudinal direction of the developing roller) are all the same. Therefore, the developing device driving output element 62 can be driven stably.

[0284] Figure 19 shows another modified example. Part (a) of Figure 19 is a sectional view in which the release cam 72 is in the external position, and part (b) of Figure 19 is a perspective view.

[0285] In the examples described above, the drive input part 74b has a twisted triangular shape, but in the modified example of Figure 20, three projections are provided as the drive input part 974b. The shapes of the driving input parts 974b are the same, and the shapes and sizes thereof can be any if the driving force of the driving output element of the developing device 62 can be received.

[0286] This modified example was described as a modification of Modality 1, but it is also applicable to the other modalities that will be described below. [Difference from conventional examples].

[0287] Here, the description will be made regarding the difference of this modality from conventional examples.

[0288] In Japanese patent application submitted for public inspection 2001337511, the developing roller is provided at the end part with a coupling for receiving the driving force from the main assembly of the image forming apparatus and a spring clutch for switch the drive transmission. Additionally, an interrelated link to the rotation of the developing unit in the process cartridge is provided. When the developing roller is spaced from the drum by the rotation of the developing unit, the link acts on the spring clutch provided at the end part of the developing roller to stop the transmission of drive to the developing roller.

[0289] The spring clutch involves variations. More particularly, there is a time from actuation of the spring clutch to the actual stopping of the drive transmission. Furthermore, due to variations in the size of the link mechanism and the variation in the rotation angle of the developing unit, the time in which the link mechanism acts on the spring clutch may vary. The actuatable link mechanism in the spring clutch is arranged not at the center of rotation of the developing unit and the drum unit.

[0290] In this embodiment, on the other hand, the structure for switching the drive transmission for the developing roller (contact part 72a of the release cam 72, contact part 73a as the operating part of the release lever 73) is employed. actuatable on it), so that the control variation of the development roller rotation period can be reduced.

[0291] Furthermore, these structural elements are arranged coaxially with the center of rotation in which the developing unit is rotatably supported by the drum unit. At the rotation axis position, the relative position error between the drum unit and the developing unit is minimal. Therefore, by placing the structure for switching the drive transmission for the developing roller on the axis or center of rotation, the switching time of the drive transmission in response to the angle of rotation of the developing unit can be more accurately controlled. As a result, the rotation period of the developing roller can be controlled with high precision and therefore the deterioration of the developer and/or the developing roller can be suppressed.

[0292] Furthermore, in some conventional image forming apparatus and process cartridge, the clutch for switching the drive transmission to the developing roller is provided in the main assembly of the image forming apparatus.

[0293] For example, when monochrome printing is performed on a four-color imaging apparatus, the actuation of developing devices containing non-black developers is prevented using the clutch. Furthermore, also in a monochrome image forming apparatus, when an electrostatic latent image on the drum is being developed by the developing device, the drive is transmitted to the developing device, but when the developing operation is not performed, the drive for the developing device is prevented using a clutch. By controlling the rotation period of the developing roller by stopping the drive transmission to the developing device during non-imaging operation, the rotation period of the developing roller is reduced and therefore the deterioration of the developer and/or of the developing roller can be suppressed.

[0294] Compared to the case in which the clutch for switching the drive transmission for the developing roller is provided in the main assembly of the image forming operation, the structure of this effective embodiment for reducing the size of the clutch (release mechanism including release cam 72 and so on, in this embodiment) to switch the drive transmission. Figure 20 is a block diagram showing an example of a gear arrangement in the main assembly of an image forming apparatus in the case where the drive force is transmitted from a motor (drive source) provided in the main assembly. of the image forming apparatus. When drive force is transmitted from a motor 83 to a process cartridge P (PK), it is transmitted through a tension gear 84 (K), a clutch 85 (K), and a tension gear 86 (K). When drive force is transmitted from a motor 83 to a process cartridge P (PY, PM, PC), it is transmitted through a tension gear 84 (YMC), a clutch 85 (YMC), and a tension gear 86 ( YMC). The engine drive 83 is divided into the drive force for the tension gear 84 (K) and the drive force for the tension gear 84, and the clutch drive 85 (YMC) is divided into the drive forces for the tension gear 86 (Y), for tension gear 86 (M) and for tension gear 86 (C).

[0295] When, for example, monochrome printing is performed on the four-color imaging apparatus, the drive transmissions to the developing devices containing non-black developers are interrupted using clutch 85 (YMC). When four-color printing is performed, the transmission from motor 83 is transmitted to the respective P process cartridges through clutch 85 (YMC). At this time, the load is concentrated on the clutch 85 (YMC) to drive the respective P process cartridges. Particularly, the clutch 85 (YMC) receives the load which is 3 times the load applied to the clutch 85. The load variations of the respective Color development devices are also applied to the 85 single clutch (YMC). To realize the drive transmission while maintaining the rotation accuracy of the developing roller even in the case of load concentration and variations, the rigidity of the clutch must be improved. Therefore, the clutch is increased in size, or a high rigidity material such as sintered metal must be used. On the other hand, when clutches are provided for respective process cartridges (release mechanism including release cam 72 and so on in this embodiment), the load and load variation are only those provided by the associated developing device. For this reason, it is not necessary to increase rigidity and therefore the clutch can be reduced in size.

[0296] In addition, the gear arrangement for the drive transmission for the black process cartridge P (PK), the load applied to the drive switching clutch 85 (K) is reduced as much as possible. In a gear arrangement of four drive transmissions for a process cartridge P, a load applied to a gear shaft is smaller when it is closer to the process cartridge P (driven element) in view of a drive transmission efficiency of the gear. Accordingly, the clutch can be reduced in size by placing the clutch between the cartridge and the main assembly compared to the housing in which the clutch is placed in the main assembly of the image forming apparatus.

[Mode 2]

[0297] With reference to Figure 21 - Figure 29, Embodiment 2 of the present invention will be described. A release cam 172, a spring 170 and a release lever 173 of this embodiment correspond to the release cam 72, the spring 70 in the release lever 73 of Embodiment 1 described above. On the other hand, the positions, structures and functions of the release cam 172, the spring 170 and the release lever 173 are partially different from those of the release cam 72, the spring 70 and the release lever 73. The description will be made in relation to Modality 2. In the following, the description may be omitted for those parts to which the description in Modality 1 applies.

[Drive transmission for developing roller]

[0298] With reference to Figures 21 and 22, the structure of the drive connection part will be described.

[0299] The drive connecting part of this embodiment includes a drive input element 74, the release lever 173, the release cam (release element, movable element) 172, the spring 170, a device cover element developer 32 and a cartridge cover element on the drive side 24.

[0300] As shown in Figures 21 and 22, a shaft portion 74x of the drive input element 74 penetrates an opening 170a of the spring 170, an opening 172f of the release cam, an opening 173d of the release lever 173, a opening 32d of the developing device cover element 32 and an opening 24e of the cartridge cover element on the drive side 24. A drive input portion 74b at the free end of the shaft portion 74x is exposed to the outside of the cartridge.

(Structure of drive connection part)

[0301] With reference to Figures 21, 22 and 23, the drive connection part will be described in more detail.

[0302] Between the cartridge cover element on the drive side 24 and a rolling element 45, the drive input element 74, the spring 170, the release cam 172, the release lever 173 on the drive element are provided. cover of the developing device 32 in the order cited from the rolling element 45 towards the cartridge cover element on the drive side 24. That is, the drive input element 74, the spring 170, the release cam 172 , the release lever 173 and the cover element of the developing device 32 are arranged in the aforementioned order from inside to outside in the longitudinal direction of the developing roller. The rotation axes of these elements are coaxial with the rotation axis (X rotation axis) of the drive input element 74.

[0303] Parts (a) and (b) of Figure 23 are schematic cross-sectional views of the connection part of the drive.

[0304] As described above, a nascent part 74p (inner surface of the cylindrical part) of the drive input element 74 and the first bearing part 45p (outer surface of the cylindrical part) of the rolling element 45 are engaged with each other. Furthermore, the cylindrical portion 74q of the drive input member 74 and the inner circumference 32q of the developing device cover member 32 are engaged with each other. That is, the drive input member 74 is rotatably supported by the bearing member 45 and the developing device cover member 32 on each of the opposing end portions.

[0305] Outside the cover element of the developing device 32 relative to the longitudinal direction of the cartridge P, the cartridge cover element on the drive side 24 is provided. Part (a) of Figure 23 is a schematic cross-sectional view illustrating an engaged state (coupled state) between the drive input portion 74b of the drive input element 74 and the recess 62b of the device drive output element. reveal 62 of the main set. In this way, the drive inlet part 74b is projected out of the cartridge beyond an opening plane of the aperture 24e of the cartridge cover element on the drive side 24.

[0306] Between the drive input element 74 and the release cam 172, the spring 170 (elastic element), as a pushing element, is provided so as to drive the release cam 172 in the direction indicated by an arrow M (out of the cartridge in the longitudinal direction of the developing roller).

[0307] Between the developing device cover member 32 and the release cam 172, the release lever 173 is provided as a thrust mechanism for pushing the release cam 172 in the direction of an arrow N (into the cartridge in the longitudinal direction of the developing roller) against a pushing force from the spring 170. The release lever 173 is a rotary element that rotates relative to the release cam 172 and the developing device holder and is an operating element for moving the release cam 172 acting on the release cam 172.

[0308] Part (b) of Figure 23 is a schematic cross-sectional view of the state in which the drive input part 74b is decoupled from the recess 62b of the drive output element of the developing device 62. The release cam 172 is movable in the direction of arrow M (out of the cartridge) being driven by spring 170. By movement of the release cam 172 in the direction of arrow M, the developing device drive output element 62 is driven to move in the direction of arrow M. direction of arrow M to space the drive output element of the developing device 62 from the drive input portion 74b. Therefore, the drive input element 74 (drive input part 74b) and the developing device drive output element 62 (recess 62b) are disengaged from each other, so that the rotational force is not transmitted from the recess 62b for drive input part 74b.

(Release mechanism)

[0309] The release mechanism (drive disconnection mechanism) will be described.

[0310] Figure 24 shows a relationship between the release cam 172, the release lever 173 and the cover member of the developing device 32. The release cam 172 includes a substantially cylindrical portion 172k, a disc portion 172g provided on the end surface of the cylindrical part 172k and expanding externally from the cylindrical part, a guide groove 172h provided in the disk part 172g. In this embodiment, the guide groove 172h is a recess of the disc portion 172 that is radially recessed.

[0311] The cylindrical part 172k of the release cam 172 penetrates the opening 173d of the release lever 173, and is slidably supported (along the axis of rotation X) in the opening 32d of the cover element of the developing device 32. In other words, the release cam 172 is movable substantially parallel to the axis of rotation of the developing roller 6 relative to the covering member of the developing device 32.

[0312] The release lever 173 is provided between the disc portion 172g of the release cam 172 and the cover element of the developing device 32. The disc portion 172g is a part to be driven (from receiving elastic force to be driven by the spring 170. Through the disc part 172g which receives the elastic force from the spring 170, the release cam 172 is driven out of the cartridge P (to the external position which will be described below in conjunction with Figure 29). That is, the disc part 172g is a force receiving part on the release member side (external force receiving part) for receiving, from the spring 170, the force to move the release cam 172 to the outer position.As will be described in detail below, the release cam 172 drives a drive output element 62 by the force received by the disc portion 172g.

[0313] The centers of the cylindrical part 172k of the release cam 72 and the opening 32d of the cover element of the developing device 32 are on the same axis.

[0314] The cover element of the developing device 32 is provided with a guide 32h as a guiding part, and the release cam 172 is provided with a guide groove 172h as a part to be guided. Guide 32h extends parallel to the axial direction. The guide 32h of the cover element of the developing device 32 is engaged with the guide groove 172h provided on the release cam 172 as the decoupling element. Due to the engagement between the guide 32h and the guide groove 172h, the release cam 172 is slideable only in the axial direction (arrows M and N) in relation to the cover element of the developing device 32.

[0315] The guide groove 172 instead of the guide 32h can be extended in parallel with the rotation axis X axis of rotation.

[0316] The guide 32h is a projection in the guide groove 172 is a recess, but the guiding part of the covering element of the developing device 32 may be a recess, and the part to be guided of the release cam 172 may be a projection, for example. The configurations are not limiting of the present invention.

[0317] Figure 25 shows the structures of the release lever 173 and the release cam 172.

[0318] The decoupling element and the release cam 172 as the movable element are provided with a contact part (inclined surface) 172a and a contact part 172c, respectively. The release lever 173 is provided with a contact part (inclined surface) 173a as an actuatable operating part on the contact part 172a of the release cam 172, and a contact part 173c as an actuable operating part on the contact part 172c of release cam 172.

[0319] The contact part 172a and the contact part 173a are inclined with respect to the rotation axis yes.

[0320] The contact portion 173c and the contact portion 172c are surfaces substantially perpendicular to the axis of rotation yes.

[0321] The release lever 173 is a rotating element that rotates about the axis of rotation X relative to the developing device support (rolling element 45, developing device cover element 32).

[0322] Figure 25 shows an example in which two of the contact parts 173a of the release lever 173, two of the contact parts 173c of the release lever 173, two of the contact parts 172a of the release cam 172 and two of the contact elements 172c of the release cam 172 are provided, but the numbers of these elements are not limited to two. For example, the numbers can be three.

[Drive Disconnect Operation]

[0323] With reference to Figure 7 and Figures 26 to 29, the operation of the drive connecting part when its state changes from the state in which the developing roller 6 and the drum 4 are in contact with each other to the state in which they are spaced from each other will be described. For better illustration, Figures 26 - 29 omit some parts, and the release lever and release cam are shown partially schematically.

[State 1]

[0324] As illustrated in part (a) of Figure 7, the spacing force impulse element 80 and the impulse force receiving part 45a of the bearing element 45 are spaced from each other by a space d. In this case, the drum 4 and the developing roller 6 come into contact with each other. This state is called “state 1” of the spacing force impulse element 80. The state of the drive connection part is as shown in Figure 27. In part (a) of Figure 27, a pair of the input element of drive 74 and the developing device drive output element 62 and the release cam 72 and release lever 73 pair are shown separately and schematically. Part (b) of Figure 27 is a perspective view illustrating a structure of the drive connecting part.

[0325] The contact part 172a of the release cam 172 and the contact part 173a of the release lever 173 are not in contact with each other. On the other hand, the contact part 172c of the release cam 172 and the contact part 173c of the release lever 173 are in contact with each other. The contact part 172c receives a reaction force from the contact part 173c in the direction of arrow N. Thereby, the release lever 173 drives the release cam 172 into the cartridge P (inward in the longitudinal direction of the roller of development, arrow N) against the force of spring 170 (Figure 22) which drives the release cam 172 in the direction of arrow M. Therefore, the release lever 173 prevents movement of the release cam 172 away from the cartridge P ( out in the longitudinal direction) to keep it in the internal position retracted into the cartridge (inward in the longitudinal direction).

[0326] That is, the contact portion 173c of the release lever functions as a limiting part to limit the outward movement of the release cam 172 by contacting the limited portion (contact portion 172c) of the release cam 172.

[0327] At this time, the developing device driving output element 62 is in the second position, and the driving input part 74b of the driving input part 74 and the developing device driving output element 62 are engaged with each other by an engagement amount q, and therefore drive transmission is possible.

[State 2]

[0328] When the spacing force impulse element 80 moves from the revealing and driving transmission contact position in the direction of an arrow F1 in the Figure by δ1, as shown in part (b) of Figure 7, the unit of development 9 rotates at an angle θ1 about the axis of rotation X in the direction of arrow K. As a result, the development roller 6 is spaced from the drum 4 by a distance ε1. The release cam 172 and the developing device cover element 32 of the developing unit 9 rotate in interrelation with the rotation of the developing unit 9 by angle θ1 in the direction indicated by an arrow K. On the other hand, when the cartridge P is mounted on the main assembly 2, the drum unit 8, the cartridge cover element on the drive side 24 and the cartridge cover element on the non-drive side 25 are fixed in place relative to the main assembly 2.

[0329] As shown in Figure 26, the release lever 173 of the developing unit 9 is provided with the force receiving part (projected part, part to be engaged) 173b designed from a ring configuration part of the lever of release 173 in a direction of a line perpendicular to the axis of rotation 73 release is limited. Even though the rotation of the release lever 173 is limited, the developing unit 9 is capable of rotating because the developing device cover element 32 is provided with an opening 32c.

[0330] The release cam 172 is rotated in interrelation with the rotation of the developing unit 9 in the direction indicated by arrow K in the Figure relative to the release lever 173 which is limited in rotation. However, a portion of the contact portion 172c of the release cam 172 and a portion of the contact portion 173c of the release lever are in contact with each other, and therefore movement of the release cam 172 in the direction of the arrow M is still limited by the release lever 173. That is, the release cam 172 is held in the inward position. At this time, the developing device driving output element 62 is in the second position, in which the driving input part 74b of the driving input element 74 and the developing device driving output element 62 remain in position. engage with each other (part (a) of Figure 28).

[0331] Therefore, the driving force introduced into the drive input element 74 of the main assembly 2 is being transmitted to the developing roller 6 through the developing roller gear 69.

[State 3]

[0332] Part (a) of Figure 29 and part (b) of Figure 29 illustrate the drive connecting part at the moment when the thrust element on the main assembly side of the spacing force thrust element 80 moves moves from the separation drive transmission position of the developing device in the direction indicated by arrow F1 in the Figure by δ2 as shown in part (c) of Figure 7. By the 80 spacing impulse element moving by δ2, the unit of revelation 9 is rotated by an angle θ2 (> θ1) by the impulse force receiving part 45a that receives the force from the spacing force impulse element 80.

[0333] In interrelationship with the rotation of the developing unit 9 through the angle θ2 by the spacing force impulse element 80, the release cam 172 and the developing device support (developing device support 29, element bearing element 45 and developing device cover element 32) are rotated in the direction indicated by arrow K in the figure. On the other hand, the release lever 173 does not change its position from the position of state 2 due to engagement with the engagement part 24s provided on the cartridge cover member 24, in a similar way to the previous example. That is, the release lever 173 rotates relative to the developing device holder and the release cam 172.

[0334] At this time, the contact surface 172c of the release cam 172 and the contact part (limiting part) 173c of the release lever 173 is broken. That is, the release cam 172 becomes unrestricted in its movement by the contact portion 173c of the release lever.

[0335] Here, as described above, the release cam 172 is capable of sliding movement in the axial direction (directions of arrows M and N) by the guide groove 172h of the release cam 172 engaging with the guide 32h of the cover element of the developing device 32 (Figure 24). Accordingly, the release cam 172 moves in the direction of the arrow M externally from the cartridge P (externally in the longitudinal direction of the developing roller) by the force of the spring 170, while the contact part 172a slides over the contact part 173a of the release lever 173.

[0336] That is, the release cam 172 slides relative to the release lever 173 in the direction of arrow M by the movement distance p. Thereby, in interrelation with the movement of the release cam 172 in the direction indicated by an arrow M, the cylindrical part 172k of the release cam 172 overlaps with the drive input portion 74b of the drive input element 74 in the direction of the axis

[0337] In short, the thrust force produced by the main assembly 2 is transmitted to the bearing element 45 (thrust force receiving part 45a) of the cartridge P through the spacing force thrust element 80. Thereby, the developing unit 9 (developing device support, release cam 172) rotates through angle θ2 (part (c) of Figure 7). Through the release lever 173 engaged with the cartridge cover element on the drive side 24 moving relative to the developing device holder and the release cam 172, the movement prevention of the release cam 172 is released. As a result, the release cam 172 is moved to the outer position and drives the drive output element of the developing device 62 to the free end of the cylindrical part 172k (thrust part) using the elastic force (thrust force). ) received by the disc portion 172g (Figure 24) from the spring 170 (Figure 21). And, the release cam 172 moves the drive output member of the developing device 62 in the direction of arrow M to retract it to the first position (part (b) of Figure 23, Figure 29).

[0338] At this time, as shown in Figures 28 and 29, the moving distance p of the developing device drive output element 62 is greater than the amount of engagement q between the drive input element 74 and the developing device drive output element 62, and therefore, the engagement between the driving input element 74 and the developing device driving output element 62 is broken. Although the development drive output element 62 of the main assembly 2 continues to rotate, the drive input element 74 stops. As a result, the rotation of the developing roller gear 69 and therefore the rotation of the developing roller 6 stops.

[0339] As the release cam 172 and the drive input portion 74b are projected in a phantom line parallel to the axis of rotation of the developing roller 6, an area of the release cam 172 and an area of the input portion drive cam 74b (rotational force receiving part 74b4, Figure 17) overlap at least partially with each other when the release cam 172 has moved to the external position. In this embodiment, the area of the drive input portion 74b is within the area of the release cam 172.

[0340] As described above, the movement distance p through which the developing device output element 62 is moved from the second position to the first position by sliding the release cam 172 is preferably greater than the amount of engagement q between the drive input element 74 and the drive output element of the developing device 62. That is, in the state that the release cam 172 is in the external position (Figure 29), the thrust part (free end of the release cam 172) of the release cam 172 is preferably external compared to the free end of the drive input part 74b in the longitudinal direction of the developing roller 6.

[0341] However, the end surface (free end) of the drive input portion 74b and the end surface of the release cam 172 may be substantially in the same plane. Furthermore, the position of the free end of the release cam 172 may be within the position of the free end of the drive input part 74b, if the drive transmission to the rotational force receiving part 74b4 (Figure 17) 2 of the element drive input 74 is not performed.

[0342] In the foregoing, the operation of the drive disconnection for the developing roller 6 in interrelation with the rotation of the developing unit 9 in the direction of arrow K has been described. By employing such a structure, the developing roller 6 can be spaced from the drum 4 while rotating. As a result, the drive transmission to the developing roller 6 may be interrupted depending on the spacing distance between the developing roller 6 and the drum 4.

[Drive connection operation]

[0343] Description will be made as to the operation of the drive connecting part when the state changes from the state in which the developing roller 6 is spaced from the drum 4 to the state in which they are in contact. This operation is opposite to the operation of the contact state for the spaced developing device state described previously.

[0344] In the state of the spaced developing device (the developing unit 9 is in the angular position θ2, as shown in part (c) of Figure 7), the drive connecting part is in the state that the input element of drive 74 and the developing device driving output element 62 are disconnected from each other, as shown in Figure 15. That is, the developing device driving output element 62 is in the first position.

[0345] When the spacing force receiving element 145 is gradually retracted from the impulse force receiving part 45a in the direction of an arrow F2, the developing unit 9 is rotated by the force of a impulse spring 95 ( Figure 4) in the direction of an arrow H shown in Figure 7 (reverse rotation compared to the K direction described above).

[0346] At this time, as shown in Figure 26, the release lever 173 does not rotate because the force receiving part 173b is in engagement with an engagement part 24t which is the limiting part for the cartridge cover element 24. As a result, the release cam 172 rotating with the developing unit 9 rotates relative to the release lever 173. That is, the release lever 173 rotates relative to the release cam 172.

[0347] By rotating the release lever 173 relative to the release cam 172, the contact part 173a (thrust part on the rotating element side, push part on the operating element side) of the release lever 173 applies a force to the contact part 172a of the release cam 172 in the direction of arrow N. The contact part 172a functions as a force receiving part (second force receiving part on the release member side, force receiving part inward) to receive from the release lever 173 the force in the direction of the arrow N (into the cartridge P).

[0348] With rotation of the release lever 173, the release cam 172 moves in the direction of arrow N against the force of the spring 170, while the contact part 172a slides on the contact part 173a.

[0349] When the developing unit 9 rotates through angle θ1 (for the state shown in part (b) of Figure 7 and Figure 28), the contact part 172c of the release cam 172 comes into contact with the contact part 173c of the release lever 173 to receive a reaction force. The contact portion 173c of the release lever 173 holds the release cam 172 in the inward position, pushing it in the direction of arrow N against the pushing force of the spring 170.

[0350] Thereby, the drive output element of the developing device 62 is also driven to the second position in the direction of arrow N by a spring (not shown) of the main assembly 2. Then, the drive input element 74 is engaged with the drive output element of the developing device 62, as shown in Figure 28.

[0351] Therefore, the driving force is transmitted from the main assembly 2 to the developing roller 6, thus rotating the developing roller 6. At this time, the developing roller 6 and the drum 4 are kept spaced apart from each other.

[0352] From this state, the spacing force push element 80 is further rotated in the direction of arrow F2 to gradually rotate the developing unit 9 in the direction of arrow H, as shown in Figure 7, whereby the development roller revelation 6 can be placed in contact with the drum 4 (part (a) of Figure 7). Also in this state, the developing device drive output element 62 is in the second position.

[0353] In the foregoing, the drive transmission operation for the developing roller 6 in interrelation with the rotation of the developing unit 9 in the direction of arrow H has been described.

[0354] In summary, when the force received by the impulse force receiving part 45a decreases by the spacing force impulse element 80 separating from the impulse force receiving part 45a, the developing unit 9 rotates in the direction of arrow H by the force of the impulse spring 95 (Figure 4). Thereby, the release lever 173 rotates relative to the release cam 172 and the developing device holder.

[0355] By utilizing the force of the impulse spring 95, the release lever 173 applies the force to the contact part of the release cam 172 (second force receiving part on the side of the release member) 172a on the contact part 173a (thrust part on the rotating element side, thrust part on the operating element side) in the direction of arrow N. That is, the release lever 173 moves the release cam 172 in the direction of arrow N using spring force of impulse 95.

[0356] When the release cam 172 moves to the internal position, the release lever 173 prevents movement of the contact part (limiting part) 172c of the release cam 172 in the direction of arrow M by the contact part (limiting part) ) 173c. Therefore, the release cam 172 is held in the internal position.

[0357] With this structure described above, the developing roller 6 is placed in contact with the drum 4 while rotating, and the driving force can be transmitted to the developing roller 6 depending on the spacing distance between the developing roller 6 and drum 4.

[0358] As described previously, with the structure described above, the switching between the drive disconnection and the drive transmission for the developing roller 6 can be definitively determined based on the rotation angle of the developing unit 9.

[Mode 3]

[0359] Referring to Figure 30 - Figure 37, Embodiment 3 of the present invention will be described. A release cam 272, a spring 270, a drive-side cartridge cover 224, and a developing device cover member 232 correspond to the release cam 72, the spring 70, the release lever 73, the cartridge cover on the drive side 24 and the cover element of the developer device 32 of Embodiment 1, respectively.

[0360] On the other hand, the positions, structures and functions of the release cam 272, the spring 270, the cartridge cover on the drive side 224 and the cover element of the developing device 232 are partially different from those of the cam release 72, spring 70, drive-side cartridge cover 24, and developing device cover element 32, respectively. In this embodiment, no release lever 73 is provided. Furthermore, the release cam (release element, movable element) 272 is rotatable with respect to the holder of the developing device. In the following, the detailed description will be made particularly on the different points of the previous modalities. In the description of this embodiment, the same reference numbers as in Embodiments 1 and 2 are assigned to elements with corresponding functions in this embodiment, and their detailed description is omitted for simplicity.

[Drive transmission for developing roller].

[0361] With reference to Figures 30 and 31, the structure of the drive connection part will be described.

[0362] In this embodiment, the drive connecting part includes a drive input element 74, the release cam 272, the spring 270, the developing device cover element 232, and the cartridge cover element on the release side. drive 224.

[0363] As shown in Figures 30, 31, the drive transmission element on the cartridge side 74 extends through an opening 224e of the cartridge cover element on the drive side 224, an opening 232d of the cartridge cover element developing device 232, an opening 270a of spring 270 and an opening 272f of cartridge cover member 224 for engaging with a drive output member of developing device 62. More particularly, as shown in Figure 30, the cover element of the cartridge on the drive side 224 which is a support provided in a longitudinal end part of the cartridge is provided with openings 224e and 224d which are through openings. The developing device cover element 232 connected to the cartridge cover element on the drive side 224 includes a cylindrical part 232b which is provided with the opening 232d which is a through opening.

[0364] A shaft portion 74x of the drive input member 74 extends through the opening 270a of the spring 270, the opening 272f of the release cam 272, the opening 232d of the cover member of the developing device 232, and the opening 224e of the cartridge cover member on the drive side 224. A drive input portion 74b at the free end of the shaft portion 74x is exposed externally from the cartridge.

(Structure of drive connection part)

[0365] With reference to Figures 30, 31 and 32, the drive connection part will be described in more detail.

[0366] The cartridge cover element on the drive side 224 is a part of the support on the longitudinal end part of the cartridge P. Between the developing cartridge cover element 224 and a rolling element 45, the inlet element of drive 74, the spring 270, the release cam 272 and the developing device cover element 232 are disposed in the direction of the rolling element 45 towards the cartridge cover element on the drive side 224. That is, in the direction from the inside toward the outside, in the longitudinal direction of the developing roller, the drive input element 74, the spring 270, the release cam 272 and the developing device cover element 232 are arranged in the aforementioned order. The rotation axes of these elements are coaxial with the rotation axis (X rotation axis) of the drive input element 74.

[0367] Parts (a) and (b) of Figure 32 are schematic cross-sectional views of the drive connection part.

[0368] As previously described, a nascent part 74p (inner surface of the cylindrical part) of the drive input element 74 and the first bearing part 45p (outer surface of the cylindrical part) of the rolling element 45 are engaged with each other. Furthermore, the cylindrical portion 74q of the drive input member 74 and the inner circumference 232q of the developing device cover member 232 are engaged with each other. That is, the drive input member 74 is rotatably supported by the bearing member 45 and the developing device cover member 232 on each of the opposing end portions.

[0369] In addition, the centers of the first rolling part 45p (outer surface of the cylindrical part) of the rolling element 45 and the inner circumference 232q of the cover element of the developing device 232 are coaxial with the axis of rotation X of the unit of revelation 9.

[0370] Outside the cover element of the developing device 232 relative to the longitudinal direction of the cartridge P, the cartridge cover element is provided on the drive side 224.

[0371] Part (a) of Figure 32 is a schematic cross-sectional view illustrating an engaged state (coupled state) between the drive input portion 74b of the drive input element 74 and the recess 62b of the drive output element. driving developing device 62 of the main assembly. In this way, the drive input part 74b is projected externally from the cartridge beyond an opening plane of the opening 224 of the cartridge cover element on the drive side 24.

[0372] Between the drive input element 74 and the release cam 272, the spring 270 (elastic element), as a thrust element, is provided to drive the release cam 272 in the direction of an arrow M (outward). of cartridge P).

[0373] Part (b) of Figure 32 is a schematic cross-sectional view of the state in which the drive input portion 74b is decoupled from the recess 62b of the developing device drive output member 62. The release cam 272 it is movable in the direction of arrow M (outside the cartridge) and is driven by spring 270.

[0374] Through movement in the direction of arrow M, the release cam 272 drives the drive output element of the developing device 62 to move it in the direction of arrow M, thereby spacing the drive output element of the developing device. development 62 of the driving input element 74. Therefore, the coupling between the driving input part 74b of the driving input element 74 and the recess 62b of the developing device driving output element 62 is broken, so that the rotational force is not transmitted from the recess 62b to the drive input part 74b.

(Release mechanism)

[0375] The release mechanism (drive disconnection mechanism) will be described.

[0376] Figure 33 shows a relationship between the release cam 272 and the developing device cover element 232. The release cam 272 is provided with a substantially cylindrical portion 272k, a disc portion 272g expanding outwardly in an inner end surface of the cylindrical part 272k, a force receiving part 272b (projected part, part to be engaged) projecting from the disc part 272g. In this embodiment, the force receiving part 272b is in the form of a projection that projects radially relative to the disc part 272g.

[0377] The cylindrical portion 272k of the release cam 272 is slidably supported relative to the opening 232d of the cover element of the developing device 232 (sliding along the axis of rotation of the developing roller 6). In other words, the release cam 272 is movable substantially parallel with the axis of rotation of the developing roller 6 relative to the covering member of the developing device 232.

[0378] The disc part 272g functions as a part to be driven (elastic force receiving part) driven by the spring 270 (Figure 30). By the disc part 272g receiving the elastic force from the spring 270, the release cam 172 is driven out of the cartridge P (to the external position which will be described below in conjunction with Figure 37).

[0379] The disc part 272g functions as a force receiving part (force receiving part on the release member side) to receive an external force from the cartridge P (outward in the longitudinal direction of the developing roller).

[0380] The centers of the cylindrical part 272k of the release cam 272 and the opening 432d of the cover element of the developing device 232 are on the same axis.

[0381] The release cam 272 as the decoupling element is provided with a contact part (inclined surface, contact surface) 272a and a contact part 272c. The cover element of the developing device 232 is provided with a contact part (inclined surface, contact surface) 232g functioning as an actuatable operating part on the contact part 272a of the release cam 272, and a contact part (surface contact part) 232f as an actuatable operating part on a contact part 272c of the release cam 272.

[0382] The contact portion 272a of the release cam 272 and the contact portion 232g of the cover element of the developing device 232 may come into contact with each other. The contact portion 272a of the release cam 272 and the contact portion 232g of the developing device cover element 232 are inclined with respect to the axis of rotation X.

[0383] The contact portion 272c of the release cam 272 and the contact portion 232f of the developing device cover element 232 may be engaged with each other. The contact portion 272c of the release cam 272 and the contact portion 232f of the developing device cover element 232 are substantially perpendicular to the X axis of rotation.

[0384] The release cam 272 is a rotating element that rotates relative to the developing device support (rolling element 45, developing device cover element 232) around the axis of rotation X. That is, the cam release mechanism 272 is capable of rotating about the X axis and sliding along the X axis relative to the rolling element 45 and the cover element of the developing device 232.

[0385] In the example of Figure 33, two of the contact parts 232g of the covering element of the developing device 232, two of the contact parts 232f thereof, two of the contact parts 272a of the release cam 272, and two of the contact details 272c of the same are provided respectively, but the numbers are not limited to two. For example, the numbers can be three.

[Drive Disconnect Operation]

[0386] Referring to Figure 7 and Figures 34 to 37, the operation of the drive connecting part when its state changes from the state in which the developing roller 6 and the drum 4 are in contact with each other to the state in which they are spaced apart from each other. For better illustration, Figures 334 - 37 omit some parts, and the release lever and release cam are shown partially schematically.

[State 1]

[0387] As illustrated in part (a) of Figure 7, the spacing force impulse element 80 and the impulse force receiving part (spacing force receiving part) 45a of the bearing element 45 are spaced one from the other by a space d. In this case, the drum 4 and the developing roller 6 come into contact with each other. This state is called “state 1” of the spacing force impulse element 80. The state of the drive connection part is as shown in Figure 35. In part (a) of Figure 35, the input element pair of drive 74 and the developing device drive output element 62, and the pair of the release cam 272 and the developing device cover element 232 are shown schematically and separately. Part (b) of Figure 35 is a perspective view illustrating a structure of the drive connection part.

[0388] The contact portion 272a of the release cam 272 and the contact portion 232g of the developing device cover element 232 do not come into contact with each other.

[0389] On the other hand, the contact part 272c of the release cam 272 and the contact part 232f of the cover element of the developing device 232 are brought into contact with each other. The contact part 272c receives a reaction force from the contact part 273f in the direction of the arrow N. That is, the cover element of the developing device 232 applies to the release mechanism 272 the force in the direction of the arrow N opposite to the direction of spring force 270 (Figure 31) driving release cam 272 in the direction of arrow M.

[0390] The contact part 232f of the developing device cover element 232 functions as a limiting part to limit the movement of the release cam 272 by the force of the spring 270 externally of the cartridge P (external position), coming into contact with a portion to be limited (the contact portion 272c) of the release cam 272. The developing device cover element 232 prevents the release cam 272 from moving outwardly from the cartridge P (in the longitudinal direction) to maintain the release cam 272. 272 in the internal position retracted into the cartridge (in the longitudinal direction).

[0391] At this time, the developing device driving output element 62 is in the second position, and the driving input part 74b of the driving input element 74 and the recess 62b of the developing device driving output element disclosure 62 are engaged with each other by an engagement amount q and therefore drive transmission is possible.

[State 2]

[0392] When the spacing force impulse element 80 moves from the revealing and driving transmission contact position in the direction of an arrow F1 in the Figure by δ1, as shown in part (b) of Figure 7, the unit of development 9 rotates at an angle θ1 about the axis of rotation X in the direction of arrow K. As a result, the development roller 6 is spaced from the drum 4 by the distance ε1. The cover element of the developing device 232 in the developing unit 9 rotates in the direction of arrow K by an angle θ1 in interrelation with the rotation of the developing unit 9. On the other hand, when the cartridge P is mounted in the main assembly 2, the drum unit 8, the cartridge cover element on the drive side 224 and the cartridge cover element on the non-drive side 25 are fixed in place relative to the main assembly 2.

[0393] As shown in Figure 34, the release cam 272 in the developing unit 9 is provided with a force receiving part (projected part, part to be engaged) 272b projected in the normal direction of the axis of rotation release cam 272. The force receiving part 272b is engaged with an engaging part 224 provided on the cartridge cover element on the drive side 224, by which the rotation is limited. Therefore, even though the rotation of the release cam 272 is limited, the developing unit 9 is capable of rotating, due to the provision of an opening 232c in the covering element of the developing device 232.

[0394] The cover element of the developing device 232 rotates in the direction of arrow K in the Figure in interrelation with the rotation of the developing unit 9, relative to the release cam 272 which is limited in rotation. However, since a portion of the contact portion 272c of the release cam 272 and a portion of the contact portion 232f of the developing device cover member 232 are in contact with each other, the release cam 272 is still limited by the revealing device cover element 232 in movement in the direction of arrow M. That is, the release cam 272 is held in the internal position. At this time, the developing device driving output element 62 is in the second position, in which the driving input part 74b of the driving input element 74 and the recess 62b of the developing device driving output element 62 are engaged with each other (part (a) of Figure 36).

[0395] Therefore, the driving force introduced into the drive input element 74 from the main assembly 2 is being transmitted to the developing roller 6 through the developing roller gear 69.

[State 3]

[0396] Part (a) of Figure 37 and part (b) of Figure 37 illustrate the drive connecting part at the moment when the thrust element on the main assembly side of the spacing force thrust element 80 moves moves from the separation position of the developing and driving transmission device in the direction indicated by the arrow F1 in the Figure by δ2 as shown in part (c) of Figure 7. By the 80 spacing impulse element moving by δ2, the unit of development 9 is rotated by an angle θ2 (> θ1) by the impulse force receiving part 45a receiving the force from the spacing force impulse element 80. In interrelation with the rotation of the development unit 9 by the element of thrust of spacing force 80 by angle θ2, the developing device support (developing device support 29, rolling element 45, the developing device cover element 232) rotates in the direction of arrow K in the Figure. On the other hand, the release cam 272 does not move from the state (position) 4 by engagement with the engagement part 224 of the cartridge cover element on the drive side 224, in a similar way as above. That is, the release cam 272 rotates relative to the holder of the developing device.

[0397] At this time, the contact part 272c of the release cam 272 and the contact part 232f of the cover element of the developing device are spaced apart from each other. That is, the release cam 272 is released from the limiting part (contact part 232f) of the release lever.

[0398] As described above, the release cam 272 can slide along the axial direction (arrows M and N) while rotating about the X axis relative to the cover element of the developing device 232.

[0399] Accordingly, the release cam 272 moves outwards from the cartridge P by the force of the spring 270 while the contact part 272a thereof slides over the contact part 232g of the cover element of the developing device 232.

[0400] That is, the release cam 272 slides relative to the cover element of the developing device 232 in the direction of arrow M by the movement distance p. Thereby, in interrelation with the movement of the release cam 272 in the direction indicated by an arrow M, the cylindrical part 272k of the release cam 272 overlaps with the drive input portion 74b of the drive input member 74 in the direction of the axis

[0401] In short, the thrust force produced by the main assembly 2 is transmitted to the bearing element 45 (thrust force receiving part 45a) of the cartridge P through the spacing force thrust element 80. Thereby, the developing unit 9 (developing device support) rotates by θ2 (part (c) of Figure 7). The developing device holder (developing device cover element 232) rotates relative to the release cam 272 engaged with the cartridge cover element on the drive side 224. Thereby the release cam 272 is released from the element cover of the developing device 232 preventing movement of the release cam 272. As a result, the release cam 272 moves to the outer position utilizing the elastic force (thrust force) received by the disc portion 272g ( receiving force on the side of the release element, Figure 33) from the spring 270 (Figure 30), and driving the output element of the developing device drive 62 by the thrust portion in the free end portion of the cylindrical portion 272k. And, the release cam 272 moves the drive output member of the developing device 62 in the direction of arrow M to retract it to the first position (part (b) of Figure 32, Figure 37).

[0402] The developing device support (developing device cover element 232) in this embodiment is a rotatable element that rotates relative to the release cam 272, and functions as an actuatable operating element on the release cam 272 to engage move in the release cam 272 relative to the input part of the driving force 74b. The developing device cover member 232 rotates relative to the release cam 272 so as to move the release cam 272 in the direction of arrow M (out of the cartridge in the longitudinal direction of the developing roller).

[0403] When the drive input element 74 retracts to the first position, the movement distance p of the developing device drive output element 62 is greater than the amount of engagement q between the drive input element 74 and the developing device drive output element 62 as shown in Figures 36 and 37, the engagement between the driving input element 74 and the developing device driving output element 62 is released. Although the developing device driving output element 62 of the main assembly 2 continues to rotate, the driving input element 74 stops. As a result, the rotation of the developing roller gear 69 and therefore the rotation of the developing roller 6 stops.

[0404] The release cam 272 and the rotational force receiving portion 74b4 (Figure 17) of the drive input portion 74b are projected on a phantom line parallel to the axis of rotation of the developing roller 6 when the release cam 272 moves to the outside position. Next, an area of the release cam 272 and an area of the rotational force receiving part 74b4 are overlapped with each other at least partially. In this embodiment, the area of the drive input portion 74b is within the area of the release cam 272.

[0405] As described above, the movement distance p through which the developing device drive output element 62 is moved from the second position to the first position by sliding the release cam 272 is preferably greater than the amount of engagement q between the drive input element 74 and the drive output element of the developing device 62. That is, in the state in which the release cam 272 is in the external position (Figure 37), the thrust part ( free end of the release cam 272) of the release cam 272 is preferably external compared to the free end of the drive input part 74b in the longitudinal direction of the developing roller 6.

[0406] However, the end surface (free end) of the drive input portion 74b and the end surface of the release cam 272 may be substantially in the same plane. Furthermore, even if the position of the free end of the release cam 272 is within the position of the free end of the drive input part 74b, it will suffice if the drive force is not transmitted to the rotational force receiving part 74b4 (Figure 17) of the drive input element 74.

[0407] In the foregoing, the operation of the drive disconnect for the developing roller 6 in interrelation with the rotation of the developing unit 9 in the direction of arrow K has been described. By employing such a structure, the developing roller 6 can be spaced from the drum 4 while rotating. As a result, the drive transmission to the developing roller 6 may be interrupted depending on the spacing distance between the developing roller 6 and the drum 4.

[Drive connection operation]

[0408] The description will be made with regard to the operation of the drive connecting part when the state changes from the state in which the developing roller 6 is spaced from the drum 4 to the state in which they are in contact with each other . This operation is opposite to the operation from the contact state to the spaced developing device state described previously.

[0409] In the state of the spaced developing device (the developing unit 9 is in the angular position θ2, as shown in part (c) of Figure 7), the drive connecting part is in the state that the input element of drive 74 and the developing device driving output element 62 are disconnected from each other, as shown in Figure 15. That is, the developing device driving output element 62 is in the first position.

[0410] When the spacing force receiving element 145 is gradually retracted from the impulse force receiving part 45a in the direction of an arrow F2, the developing unit 9 is rotated by the force of a impulse spring 95 (Figure 4 ) in the direction of an arrow H shown in Figure 7 (inverse rotation compared to the K direction described above).

[0411] At this time, as shown in Figure 34, the force receiving part 272b of the release cam 272 is engaged with the engaging part 224t which is the limiting part for the cartridge cover element on the drive side 224 and is not rotated. As a result, the developing device cover element 232 rotates relative to the release cam 272.

[0412] By rotating the cover element of the developing device 232 relative to the release cam 272, the contact part of the cover element 232 (thrust part on the support side of the developing device, thrust part on the rotating element side, thrust part on the operating element side) 232g applies a force to the contact part 272a of the release cam 272 in the direction of arrow N. The contact part 272a functions as a second force receiving part on the release element side (inward force receiving part) to receive the inward force from the P cartridge.

[0413] As a result, with rotation of the developing device cover element 232, the release cam 272 moves in the direction of arrow N against the force of spring 270 while the contact portion 272a slides over the contact 232g.

[0414] In this state in which the developing unit 9 rotates through angle θ1 (part (b) of Figure 7 and Figure 36), the contact part 272c of the release cam 272 begins to come into contact with the contact part 232f of the covering element of the developing device 232 which receives the force from the contact part 232f. The contact portion 232f of the cover member of the developing device 232 retains the release cam 272 in the internal position against the pushing force of the spring 270.

[0415] With the release cam 272 separating from the developing device drive output element 62, the developing device driving output element 62 is driven by a spring (not shown) of the main assembly 2 to move it. move in the direction of arrow N to the second position. Then, the drive input element 74 is engaged with the drive output element of the developing device 62, as shown in Figure 14.

[0416] With this, the driving force is transmitted from the main assembly 2 to the developing roller 6, thus rotating the developing roller 6. At this time, the developing roller 6 and the drum 4 are kept spaced apart from each other.

[0417] Then, the spacing force push element 80 is gradually moved in the direction of arrow F2, and the developing unit 9 is further rotated in the direction of arrow H shown in Figure 7, whereby the developing roller 6 may come into contact with drum 4 (part (a) of Figure 7). Also in this state, the developing device drive output element 62 is in the second position.

[0418] In summary, when the force received by the impulse force receiving part 45a decreases by the spacing force impulse element 80 separating from the impulse force receiving part 45a, the developing device support (developing element developing device cover 232) of the developing unit 9 rotates in the direction of arrow H by the force of the push spring 95 (Figure 4).

[0419] Using the force of the impulse spring 95, the cover element of the developing device 232 applies the force in the contact part 232g (impulse part on the side of the rotating element) to the contact part (second force receiving part on the release member side) 272a of the release cam 272 in the direction of arrow N. That is, the developing device cover member 232 rotates using the force of the push spring 95 to move the release cam 172 in the direction of the arrow N.

[0420] When the release cam 272 is moved to the internal position, the cover element of the developing device 232 limits the movement of the contact part (limited part) 272c of the release cam 272 in the direction of arrow M, by the contact (limiting part) 232f. Therefore, the release cam 272 is held in the internal position.

[0421] In the foregoing, the drive transmission operation for the developing roller 6 in interrelation with the rotation of the developing unit 9 in the direction of arrow H was described with the structure described above, the developing roller 6 is placed in contact with the drum 4 during rotation, and the driving force can be transmitted to the developing roller 6 depending on the spacing distance between the developing roller 6 and the drum 4.

[0422] As described previously, with the structure described above, the switching between the drive disconnection and the drive transmission for the developing roller 6 can be definitively determined based on the rotation angle of the developing unit 9.

[Mode 4]

[0423] With reference to Figure 38 - Figure 45, Embodiment 4 of the present invention will be described. A release cam (release element) 372, a spring 370, a cartridge cover on the drive side 324 and a developing device cover element 332 in this embodiment correspond to the release cam 72, the spring 70, the release lever release 73, to the cartridge cover on the drive side 24 and to the developing device cover element 32, respectively.

[0424] On the other hand, the positions, structures and functions of the release cam 372, the spring 370, the cartridge cover on the drive side 324 and the cover element of the developing device 324 are partially different from those of the cam release 72, spring 70, drive-side cartridge cover 24, and developing device cover element 32, respectively. In this embodiment, no release lever 73 is provided. On the other hand, the release cam 372 is rotatable with respect to the developing device holder. In the following, the detailed description will be made particularly on the different points of the previous modalities. In the description of this embodiment, the same reference numbers as the Embodiments described above are assigned to the elements that have the corresponding functions in this embodiment, and their detailed description is omitted for simplicity.

[Drive transmission for developing roller]

[0425] With reference to Figures 38 and 39, the structure of the drive connection part will be described.

[0426] In this embodiment, the drive connecting part includes a drive input element 74, the release cam 372, the spring 370, the developing device cover element 332, and the cartridge cover element on the release side. drive 324.

[0427] As shown in Figures 38 and 39, the drive input element 74 penetrates an opening 324e of the cartridge cover element on the drive side 324, an opening 332d of the developing device cover element 332, an opening 370a of spring 370 and an opening 372f of release cam 372. The drive input element 74 is in mating engagement with the drive output element of the developing device 62. More particularly, as shown in Figure 38, the element of the cartridge cover on the drive side 324 which is a support provided on a longitudinal end part of the cartridge is provided with openings 324e and 324d which are through openings. The developing device cover element 332 connected to the cartridge cover element on the drive side 324 includes a cylindrical part 332b which is provided with the opening 332d which is a through opening.

[0428] The shaft portion 74x of the drive input member 74 is penetrated through the opening 332d of the cover member of the developing device 332, the opening 372f of the release cam 372, the opening 370a of the spring 370 and the opening 324e of the cartridge cover member on the drive side 324. A drive input portion 74b at the free end of the shaft portion 74x is exposed outside the cartridge.

(Structure of drive connection part)

[0429] With reference to Figures 38, 39 and 40, the drive connection part will be described in more detail.

[0430] The cartridge cover element 324 is a part of the support at the longitudinal end part of the cartridge P. Between the cartridge cover element on the drive side 324 and the rolling element 45, the drive input element 74 , the developing device cover member 332, the release cam 372 and the spring 370, arranged in the aforementioned order from the rolling member 45 towards the cartridge cover member 324. That is, the inlet element of drive 74, the developing device cover element 332, the release cam 372 and the spring 370 are arranged in the aforementioned order from inside to outside in the longitudinal direction of the developing roller. The rotation axes of these elements are coaxial with the rotation axis (X rotation axis) of the drive input element 74.

[0431] Parts (a) and (b) of Figure 40 are schematic cross-sectional views of the drive connection part.

[0432] As described above, a nascent part 74p (inner surface of the cylindrical part) of the drive input element 74 and the first bearing part 45p (outer surface of the cylindrical part) of the rolling element 45 are engaged with each other. Furthermore, the cylindrical portion 74q of the drive input member 74 and the inner circumference 332q of the developing device cover member 332 are engaged with each other. That is, the drive input member 74 is rotatably supported by the bearing member 45 and the developing device cover member 332 on each of the opposing end portions.

[0433] Furthermore, the centers of the first rolling part 45p (outer surface of the cylindrical part) of the rolling element 45 and the inner circumference 332q of the cover element of the developing device 332 are coaxial with the axis of rotation X of the unit of revelation 9.

[0434] Outside the cover element of the developing device 332 in relation to the longitudinal direction of the cartridge P, the cartridge cover element is provided on the drive side 24. Part (a) of Figure 40 is a schematic cross-sectional view illustrating the coupling state between the drive input part 74b of the drive input element 74 and the recess 62b of the developing device drive output element 62 provided in the main assembly. In this way, the drive inlet part 74b is projected out of the cartridge beyond an opening plane of the aperture 324e of the cartridge cover element on the drive side 324.

[0435] Between the cartridge cover element on the drive side 324 and the release cam 372, the spring 370 is an elastic element as a thrust element to drive the release cam 372 in the direction of arrow N (into the cartridge).

[0436] Part (b) of Figure 40 is a schematic cross-sectional view illustrating a spaced state (decoupled state) between the drive input portion 74b of the drive input element 74 and the recess 62b of the drive output element. drive of developing device 62. The release cam 372 is movable in the direction of arrow M (to the outside of the cartridge) against the pushing force of spring 370. By movement of the release cam 372 in the direction of arrow M, the developing device driving output element 62 is driven to move in the direction of arrow M to space the developing device driving output element 62 from the driving input portion 74b. Therefore, the driving input element 74 and the developing device driving output element 62 are decoupled from each other, so that rotational force is not transmitted from the developing device driving output element 62 to a drive input part 74b.

(Release mechanism)

[0437] The release mechanism (drive disconnection mechanism) will be described.

[0438] Figure 41 shows a relationship between the release cam 372 and the cover element of the developing device 332. The release cam 372 is provided with a substantially cylindrical portion 372k (Figure 39), a disc portion 372g expanding Outward from the cylindrical part on the inner end surface of the cylindrical part 372k, a force receiving part 372b (projected part, part to be engaged) projects from the disc part 372g. In this embodiment, the force receiving part 372b is in the form of a projection that projects radially relative to the disc part 372g.

[0439] The cylindrical portion 372k (Figure 39) of the release cam 372 is supported to slide relative to the opening 324e of the cartridge cover element on the drive side 324 (sliding along the axis of rotation of the developing roller 6). In other words, the release cam 372 is movable relative to the cartridge cover member on the drive side 324 substantially parallel to the axis of rotation of the developing roller 6.

[0440] The disc part 372g functions as a part to be driven (elastic force receiving part) driven by the spring 3370 (Figure 38). The disc portion 372g receives the elastic force from the spring 370 to drive the release cam 372 into the cartridge P (the internal position will be described below, Figure 45). The disk part 372g functions as a force receiving part (second force receiving part on the release member side) to receive the force into the cartridge P in the longitudinal direction of the developing roller. The center of the cylindrical portion 372k of the release cam 372 and the center of the opening 324e of the cartridge cover member on the drive side 324 are coaxial with each other.

[0441] The release cam 372 as decoupling element is provided with a contact part (inclined surface, contact surface) 372a. Furthermore, the cover element of the developing device 332 is provided with a contact part (inclined surface, contact) 332g as an actuatable operating part on the contact part 372a of the release cam 372. The contact part 372a of the cam release 372 and the contact portion 332g of the covering member of the developing device 332 may come into contact with each other. The contact portion 372a of the release cam 372 and the contact portion 332g of the developing device cover element 332 are inclined with respect to the axis of rotation X.

[0442] The release cam 372 is a rotating element that rotates relative to the developing device support (rolling element 45, developing device cover element 332) around the axis of rotation X. That is, the cam release mechanism 372 is capable of rotating about the X axis and sliding along the X axis relative to the rolling element 45 and the cover element of the developing device 332.

[0443] In the example of Figure 41, two of the contact parts 332g of the cover element of the developing device 332 and two of the contact parts 372a of the release cam 372, but the numbers are not limited to two. For example, the numbers can be three.

[Drive Disconnect Operation]

[0444] With reference to Figure 7 and Figures 42 to 45, the operation of the drive connecting part when its state changes from the state in which the developing roller 6 and the drum 4 are in contact with each other to the state in which they are spaced apart from each other. For better illustration, Figures 42 - 45 omit some parts, and the release lever and release cam are shown partially schematically.

[State 1]

[0445] As shown in part (a) of Figure 7, the spacing force impulse element 80 and the impulse force receiving part (spacing force receiving part) 45a of the bearing element 45 are spaced one from the other by a space d. In this case, the drum 4 and the developing roller 6 come into contact with each other. This state is called “state 1” of the spacing force impulse element 80. The state of the drive connection part is as shown in Figure 43. In part (a) of Figure 35, the input element pair of drive 74 and the developing device drive output element 62, and the pair of the release cam 372 and the developing device cover element 332 are shown schematically and separately. Part (b) of Figure 43 is a perspective view illustrating a structure of the drive connecting part.

[0446] Between the contact part 372a of the release cam 372 and the contact part 332g of the cover element of the developing device 332, there is a space e.

[0447] In this case, the release cam 372 is in the inner position, and the drive output element of the developing device 62 is in the second position, so that the drive input part 74b of the drive input element 74 and the drive output element of the developing device 62 are engaged with each other by an engagement amount q and therefore drive transmission is enabled.

[State 2]

[0448] When the spacing force impulse element (impulse element on the side of the main assembly) 80 moves by δ1 in the direction of arrow F1 from the trigger disclosure and transmission contact state and, as shown in part (b) of Figure 7, the developing unit 9 rotates around the axis of rotation X by angle θ1 in the direction of arrow K, as described previously. As a result, the developing roller 6 is spaced from the drum 4 by a distance ε1. The cover element of the developing device 332 in the developing unit 9 rotates in the direction of arrow K by an angle θ1 in interrelation with the rotation of the developing unit 9. On the other hand, when the cartridge P is mounted in the main assembly 2, the drum unit 8, the drive-side cartridge cover member 324 and the non-drive-side cartridge cover member 25 are fixed in place relative to the main assembly 2.

[0449] As shown in Figure 34, the release cam 372 in the developing unit 9 is provided with a force receiving part (projected part, part to be engaged) 372b projected in a direction normal to the axis of rotation of the release cam 372. The force receiving part 372b is engaged with an engaging part 324 provided on the cartridge cover element on the drive side 324, by which the rotation is limited. Therefore, even though the rotation of the release cam 372 is limited, the developing unit 9 is capable of rotating, due to the provision of an opening 332c in the covering element of the developing device 332.

[0450] The cover element of the developing device 332 rotates in the direction of arrow K in the Figure in interrelation with the rotation of the developing unit 9, relative to the release cam 372 which is limited in rotation. The contact portion 372a of the release cam 372 and the contact portion 332g of the developing device cover member 332 begin to come into contact with each other.

[0451] Also at this time, the release cam 372 is in the internal position, and the developing device drive output element 62 is in the second position, so that the engagement between the drive input portion 74b of the developing element drive input 74 and the developing device drive output element 62 is maintained (part (a) of Figure 44).

[0452] Accordingly, the driving force introduced into the drive input element 74 of the main assembly 2 is being transmitted to the developing roller 6 through the developing roller gear 69.

[State 3]

[0453] Part (a) of Figure 45 and part (b) of Figure 45 illustrate the drive connecting part at the moment when the thrust element on the main assembly side of the spacing force thrust element 80 moves moves from the separation drive transmission position of the developing device in the direction indicated by arrow F1 in the Figure by δ2 as shown in part (c) of Figure 7. By the spacing force impulse element 80 moving by δ2, the developing unit 9 is rotated by an angle θ2 (> θ1) by the impulse force receiving part 45a receiving the force from the spacing force impulse element 80. In interrelation with the rotation of the developing unit 9 by the spacing force push element 80 through angle θ2, the developing device support (developing device support 29, rolling element 45, the developing device cover component 332) rotates in the direction of arrow K in Figure . On the other hand, the release cam 372 does not move from the state (position) 4 by engagement with the engagement part 324s of the cartridge cover element on the drive side 224, in a similar way as above. That is, the release cam 372 rotates relative to the holder of the developing device. At this time, the contact part (first force receiving part on the release member side) 372a of the release cam 372 receives a reaction force from the contact part 332g of the cover on the developing side 332.

[0454] The release cam 372 is capable of sliding movement along the X axis in the directions of arrows M and N, while rotating about the X axis relative to the cover element of the developing device 332.

[0455] Accordingly, the release cam 372 moves outwards from the cartridge P (outwards in the longitudinal direction of the developing roller), while the contact portion 372a slides on the contact portion 332g by the force received by the contact portion 372a from the contact portion 332g of the developing device cover element 332. That is, the release cam 372 slides in the direction of arrow M for the movement distance p while rotating relative to the device cover element of development 332. In interrelation with the movement of the release cam 372 in the direction of arrow M, the cylindrical portion 372k of the release cam 372 becomes overlapped with the drive input portion 74b of the drive input member 74 in the direction of the axis

[0456] In short, the thrust force supplied by the main assembly 2 is transmitted to the bearing element 45 (thrust force receiving part 45a) of the cartridge P through the spacing force thrust element 80. Thereby, the developing unit 9 (developing device support) rotates by θ2 (part (c) of Figure 7). Therefore, the holder of the developing device (developing device cover element 332) rotates relative to the release cam 372 engaged with the cartridge cover element on the drive side 324. Thereby, the contact part 372a of the release cam 372 receives force from the contact portion 332g of the cover member of the developing device 332. As a result, the release cam 372 moves to the outward position against the elastic force (thrust force) received from the second force receiving part on the release element side (disc part 372g, Figure 41) from the spring 370 (Figure 38).

[0457] The developing device support (developing device cover element 332) in this embodiment is a rotatable element that rotates relative to the release cam 372, and is an actuatable operating element on the release cam 372 to move the release cam 372 relative to the drive input portion 74b. The developing device cover member 332 moves the release cam 372 in the direction of arrow M (out of the cartridge in the longitudinal direction of the developing roller).

[0458] The contact part 332g of the cover element of the developing device 332 functions as a thrust part on the side of the rotating element (thrust part on the support side of the developing device, thrust part of the operating element) to apply the force to the force receiving portion on the release member side (contact portion 372a) of the release cam 372 by rotating the developing cover 332. The contact portion 332g applies the force to the contact portion 372a of the release cam. release 372 out of cartridge P (in the longitudinal direction of development).

[0459] The contact part 372a is an external force receiving part (first force receiving part on the release member side) directed outwardly from the P cartridge.

[0460] The release cam 372 drives the drive output element of the developing device 62 by the thrust portion at the free end of the cylindrical portion 372k (Figure 38) by moving to the outward position. And, the release cam 372 moves the drive output member of the developing device 62 in the direction of arrow M to retract it to the first position (part (b) of Figure 40, Figure 45).

[0461] At this time, as shown in Figures 44 and 45, the moving distance p of the developing device drive output element 62 is greater than the amount of engagement q between the drive input element 74 and the developing device drive output element 62, and therefore, the engagement between the driving input element 74 and the developing device driving output element 62 is broken. Although the developing device driving output element 62 of the main assembly 2 continues to rotate, the driving input element 74 stops. As a result, the rotation of the developing roller gear 69 and therefore the rotation of the developing roller 6 stops.

[0462] The release cam 372 and the rotational force receiving portion 74b4 (Figure 17) of the drive input portion 74b are projected in a phantom line parallel to the axis of rotation of the developing roller 6 when the release cam 272 moves to the outside position. Thus, an area of the release cam 372 and an area of the rotational force receiving part 74b4 are at least partially overlapping. In this embodiment, the area of the drive input portion 74b is within the area of the release cam 372.

[0463] As described above, the movement distance p through which the drive output element of the developing device 62 is moved from the second position to the first position by sliding the release cam 372 is preferably greater than the amount of engagement q between the drive input element 74 and the drive output element of the developing device 62. That is, in the state in which the release cam 372 is in the external position (Figure 45), the thrust part ( free end of the release cam 372) of the release cam 372 is preferably external compared to the free end of the drive input part 74b in the longitudinal direction of the developing roller 6.

[0464] However, the end surface (free end) of the drive input portion 74b and the end surface of the release cam 372 may be substantially in the same plane. In the state where the release cam 372 is in the outer position, even if the position of the free end of the release cam 372 is within the position of the free end of the drive input part 74b, it is sufficient that the drive force is not transmitted to the rotational force receiving portion 74b4 (Figures 17) of the drive input element 74.

[0465] In the foregoing, the operation of the drive disconnect for the developing roller 6 in interrelation with the rotation of the developing unit 9 in the direction of arrow K has been described. By employing such a structure, the developing roller 6 can be spaced from the drum 4 while rotating. As a result, the drive transmission for the developing roller 6 can be stopped depending on the spacing distance between the developing roller 6 and the drum 4.

[Drive connection operation]

[0466] Description will be made as to the operation of the drive connecting part when the state changes from the state in which the developing roller 6 is spaced from the drum 4 to the state in which they are in contact. This operation is opposite to the operation from the contact state to the spaced developing device state described previously.

[0467] In the state of the spaced developing device (the developing unit 9 is in the angular position θ2, as shown in part (c) of Figure 7), the drive connecting part is in the state that the input input element of drive 74 and the developing device driving output element 62 are disconnected from each other, as shown in Figure 45. That is, the developing device driving output element 62 is in the first position.

[0468] When the spacing force receiving element 145 is gradually retracted from the impulse force receiving part 45a in the direction of an arrow F2, the developing unit 9 is rotated by the force of a impulse spring 95 ( Figure 4) in the direction of an arrow H shown in Figure 7 (reverse rotation compared to the K direction described above).

[0469] At this time, as shown in Figure 42, the force receiving part 272b of the release cam 372 is engaged with the engaging part 324t which is the limiting part for the cartridge cover element on the drive side 324 and is not rotated. As a result, the developing device cover element 332 rotates relative to the release cam 372.

[0470] With rotation of the developing device cover element 332, the contact portion 332g of the developing device cover element 332 begins to retract from the contact portion 372a of the release cam 372. release 372 is moved by the force of spring 370 in the direction of arrow N by the amount corresponding to the retraction of the contact part 332g.

[0471] In the state in which the developing unit 9 has rotated by angle θ1 (part (b) of Figure 7 and Figure 44), the release cam 372 is in the internal position by the pushing force of the spring 370.

[0472] Upon separation of the release cam 372 from the developing device drive output element 62 by movement to the internal position, the developing device drive output element 62 is moved to the second position by the spring (not shown) of the main assembly 4, driving it towards the release cam 372. Then, the drive input element 74 is engaged with the drive output element of the developing device 62, as shown in Figure 44.

[0473] With this, the driving force is transmitted from the main assembly 2 to the developing roller 6, thus rotating the developing roller 6. At this time, the developing roller 6 and the drum 4 are kept spaced apart from each other. other.

[0474] From this state, the developing unit 9 is gradually rotated in the direction of arrow H in Figure 7, through which the developing roller 6 can come into contact with the drum 4 (part (a) of Figure 7) . Also in this state, the developing device drive output element 62 is in the second position. In the foregoing, the drive transmission operation for the developing roller 6 in interrelation with the rotation of the developing unit 9 in the direction of arrow H has been described with the structure described above, the developing roller 6 is brought into contact with the drum 4 during rotation, and the driving force can be transmitted to the developing roller 6 depending on the spacing distance between the developing roller 6 and the drum 4.

[0475] As described previously, with the structure described above, the switching between the drive disconnection and the drive transmission for the developing roller 6 can be definitively determined based on the rotation angle of the developing unit 9.

[Mode 5]

[0476] With reference to Figure 46 - Figure 53, Embodiment 5 of the present invention will be described. In this embodiment, a release member 472, a cartridge cover on the drive side 424, and a developing device cover member 432 correspond to the release cam 72, the spring 70, the release cam 72, the cartridge cover on the drive side 24 and the covering element of the developing device 32, respectively.

[0477] On the other hand, the arrangements, structures and functions of the release element 472, the cartridge cover on the drive side 424 and the developing device cover element 432 are partially different from those of the release cam 72, the cover of the cartridge on the drive side 24 and the cover element of the developing device 32. Furthermore, the release lever 73 and the spring 70 are not provided in this embodiment. In the following, the detailed description will be made particularly on the different points of the previous modalities. In the description of this embodiment, the same reference numbers as Embodiments 1 and 2 are assigned to the elements that have the corresponding functions in this embodiment, and their detailed description is omitted for simplicity.

[Drive transmission for developing roller].

[0478] With reference to Figures 46 and 47, the structure of the drive connection part will be described.

[0479] The drive connecting part of this embodiment includes the drive input element 74, the release element (decoupling element) 472, the developing device cover element 432 and the cartridge cover element on the release side. drive 424.

[0480] As illustrated in Figures 46 and 47, the cartridge drive transmission element 74 penetrates an opening 424e of the cartridge cover element on the drive side 424, an opening 472f of the release element 472, and an opening 432d of the developing device cover element 432 and engages with the developing device drive output element 62. More particularly, as shown in Figure 46, the cartridge cover element on the drive side 424 which is a support provided on a longitudinal end part of the cartridge is provided with openings 424e and 424d which are through openings. The developing device cover element 432 connected with the cartridge cover element on the drive side 424 includes a cylindrical part 432b which is provided with the opening 432d which is a through opening.

[0481] A shaft portion 74x of the drive input element 74 penetrates the opening 432d of the cover element of the developing device 432, the opening 472f of the release element, the opening 424e of the cartridge cover element on the drive side 424. A drive input portion 74b at the free end of the shaft portion 74x is exposed externally from the cartridge.

(Structure of drive connection part)

[0482] With reference to Figures 46, 47 and 48, the drive connection part will be described in more detail. In a longitudinal end part of the cartridge P, the cartridge cover element on the drive side 424 is provided as a support part. The drive input member 74, the developing device cover member 432 and the release member 472 are arranged in the aforementioned order from the rolling member 45 toward the cartridge cover member on the drive side 424 (from the inside to outside in the longitudinal direction of the developing roller). The rotation axes of these elements are coaxial with the rotation axis (X rotation axis) of the drive input element 74.

[0483] Parts (a) and (b) of Figure 48 are schematic cross-sectional views of the drive connection part. As described above, a nascent part 74p (inner surface of the cylindrical part) of the drive input element 74 and the first bearing part 45p (outer surface of the cylindrical part) of the rolling element 45 are engaged with each other. Furthermore, the cylindrical portion 74q of the drive input member 74 and the inner circumference 432q of the developing device cover member 432 are engaged with each other. That is, the drive input member 74 is rotatably supported by the bearing member 45 and the developing device cover member 432 on each of the opposing end portions.

[0484] Furthermore, the centers of the first rolling portion 45p (outer surface of the cylindrical portion) of the rolling element 45 and the inner circumference 432q of the cover element of the developing device 432 are coaxial with the axis of rotation X of the unit. development device 9. Outside the developing device cover element 432 relative to the longitudinal direction of the cartridge P, the cartridge cover element on the drive side 424 is provided.

[0485] Part (a) of Figure 48 is a schematic cross-sectional view illustrating a coupled state between the drive input portion 74b of the drive input element 74 and the recess 62 of the drive output element. disclosure 62. In this way, the drive inlet part 74b is projected out of the cartridge beyond an opening plane of the aperture 424e of the cartridge cover member on the drive side 424.

[0486] Part (b) of Figure 48 is a schematic cross-sectional view of the state in which the drive input part 74b is decoupled from the recess 62b of the drive output element of the developing device 62. The release element 472 is movable in the direction of arrow M (out of the cartridge). By movement in the direction of arrow M, the release member 472 drives the developing device driving output element 62 to move in the direction of arrow M, thereby spacing the developing device driving output element 62 from of the drive input part 74b. Therefore, the driving input element 74 and the developing device driving output element 62 are decoupled from each other, so that rotational force is not transmitted from the developing device driving output element 62 for a drive input part 74b.

(Release mechanism)

[0487] The release mechanism (drive disconnection mechanism) will be described.

[0488] Figure 49 shows a relationship between the release member 472 and the cover member of the developing device 432. The release member 472 includes a cylindrical portion 472k (substantially cylindrical portion 472k), an expanding disk portion 472g. If outwardly from the outside on the inner end surface of the cylindrical part 472k, a force receiving part 472b (projected part, part to be engaged) projects from the disc part 472g. In this embodiment, the force receiving part 472b is in the form of a projection that projects radially relative to the disc part 472g. The 472g disc part is provided with a 472h guide groove. The guide groove 472h is a recess recessed in the radial direction of the disc portion 472g.

[0489] The cylindrical portion 472k of the release member 472 is supported so that it can slide (along the axis of rotation of the developing roller 6) relative to the opening 424e of the cartridge cover member on the drive side 424. In In other words, the release member 472 is movable substantially parallel to the axis of rotation of the developing roller 6 relative to the cartridge cover member on the drive side 424.

[0490] The center of the cylindrical portion 472k of the release member 472 and the center of the opening 424e of the cartridge cover member on the drive side 424 are coaxial to each other.

[0491] The cover element of the developing device 432 is provided with a guide 432h as a guiding part, and the release element 472 is provided with a guide groove 472h as a part to be guided, as described above. Guide 432h extends parallel to the axial direction. The guide 432h of the cover member of the developing device 432 is engaged with the guide groove 472h of the release member 472. Through engagement between the guide 432h and the guide groove 472h, the release member 472 is slideable only in the axial direction ( arrows M and N) in relation to the developing device cover element 432.

[0492] In place of the parallel arrangement of the guide 432h, the guide groove 472h may be made parallel to the axis of rotation X. The release member 472 may be made movable in parallel with the axis of rotation 472g is increased, and the guide groove 472h is extended in the disc portion 472g in parallel with the axis of rotation X. It is not always necessary for the release member 472 to move parallel with the axis of rotation relative to the X axis of rotation.

[0493] Figure 50 shows the cartridge cover element on the drive side 424. The force receiving part (part to be engaged, force receiving part on the projecting part release element side) 472b of the release 472 may contact the engagement part (contact part, contact surface) 424t and the engagement part (contact part, the contact surface) 424s of the cartridge cover member on the drive side 424. coupling part 424 and the coupling part 424t are inclined with respect to the axis of rotation X (inclined surface).

[Drive Disconnect Operation]

[0494] Referring to Figure 7 and Figures 50 to 53, the operation of the drive connecting part when its state changes from the state in which the developing roller 6 and the drum 4 are in contact with each other in the state in which they are spaced. In Figures 50 to 53, some parts and structure of the release element 472 are illustrated schematically for better illustration.

[State 1]

[0495] As shown in part (a) of Figure 7, the spacing force impulse element 80 and the impulse force receiving part (spacing force receiving part) 45a of the bearing element 45 are spaced one from the other by a space d. In this case, the drum 4 and the developing roller 6 come into contact with each other. This state is called “state 1” of the spacing force impulse element 80. The state of the driving connecting part is as shown in Figure 51. In part (a) of Figure 51, the engagement part between the driving element driving input element 74 and the driving output element of the developing device 62 is illustrated schematically. Part (b) of Figure 51 is a perspective view illustrating a structure of the drive connecting part.

[0496] Between the force receiving part 472b of the release member 472 and the engaging part 424 of the cartridge cover member on the drive side 424, a space is provided. The release member 472 is in the inner position, and the drive output element of the developing device 62 is in the second position, so that the drive input part 74b of the drive input element 74 and the drive output element developing device drive 62 are engaged with each other by an engagement amount q and therefore drive transmission is enabled.

[State 2]

[0497] When the spacing force impulse element (impulse element on the main assembly side) 80 moves by δ1 in the direction of arrow F1 from the drive disclosure and transmission contact state, as shown in part (b) of Figure 7, the development unit 9 rotates around the axis of rotation X by angle θ1 in the direction of arrow K, as described previously. As a result, the developing roller 6 is spaced from the drum 4 by a distance ε1. The release member 472 and the developing device cover element 432 in the developing unit 9 rotate in the direction of arrow K by angle θ1 in interrelationship with the developing unit 9. On the other hand, when the cartridge P is mounted on the side of the main assembly 2, the drum unit 8, the cartridge cover element on the drive side 424 and the cartridge cover element on the non-drive side 25 are fixed in place relative to the main assembly 2. , the release member 472 rotates relative to the cartridge cover member on the drive side 424. In other words, the cartridge cover member on the drive side 424 rotates relative to the release member 472.

[0498] Part (a) of Figure 52 and part (b) of Figure 52 illustrate the state of the drive connection part. Through rotation of the release member 472, the force receiving part 472b of the release member 472 and the engaging part 424 of the cartridge cover member on the drive side 424 begin to come into contact with each other. Also in this state, the release element 472 is still in the inner position, and the developing device drive output element 62 is still in the second position, and therefore the drive input element 74 and the drive output element of developing device 62 are kept engaged with each other (part (a) of Figure 52).

[0499] Therefore, the driving force introduced into the drive input element 74 of the main assembly 2 is being transmitted to the developing roller 6 through the developing roller gear 69.

[State 3]

[0500] Part (a) of Figure 53 and part (b) of Figure 53 illustrate the drive connecting part at the moment when the thrust element on the main assembly side of the spacing force thrust element 80 moves moves from the separation drive transmission position of the developing device in the direction indicated by arrow F1 in Figure by δ2 as shown in part (c) of Figure 7.

[0501] By the spacing force impulse element 80 moving by δ2, the developing unit 9 is rotated by an angle θ2 (> θ1) by the impulse force receiving part 45a receiving the force from the element of spacing force impulse element 80. In interrelation with the rotation of the developing unit 9 by the spacing force impulse element 80 by angle θ2, the release element 472 and the developing device support (the device support developing device 29, the rolling element 45, the developing device cover element 432) rotate in the direction indicated by arrow K in the figure.

[0502] The release member 472 rotates while the force receiving portion 472b is in contact with the engagement portion 424 of the cartridge cover member on the drive side 424. Therefore, the release member 472 rotates relative to the cartridge cover element on the drive side 424, and receives a reaction force from the engagement portion 424s. The engaging part 424s is a surface inclined with respect to the rotation axis

[0503] As described above, the release element 472 is sliding only in the axial direction (arrows M and N) by engagement between the guide groove 472h of the release element 472 and the guide 432h of the cover element of the developing device 432 ( Figure 10).

[0504] Accordingly, the release member 472 moves outward from the cartridge P (outward in the longitudinal direction of the developing roller) by the force received by the force receiving portion 472a from the engaging portion 424s of the release member. drive-side cartridge cover 424. When the release member 472 moves, the force receiving portion 472b slides relative to the engagement portion 424 of the drive-side cartridge cover member 424.

[0505] The engaging part 424s functions as a thrust part (first thrust part on the operating element side, first thrust part on the rotating element side, first thrust part on the photosensitive element holder side) to apply the external force for the force receiving part (force receiving part on the releasing element side) 472b.

[0506] Thus, the release member 472 rotates in the direction of arrow K (part (c) of Figure 7) relative to the cartridge cover member on the drive side 424 and slides through the movement distance p in the direction of arrow M In interrelation with the movement of the release element 472 in the direction of arrow M, the cylindrical part 472k of the release element 472 is superimposed with the drive input portion 74b of the drive input element 74 in the direction of the X axis. The free end of the cylindrical part 472k of the release member 472 slides the output drive member of the developing device 62 in the direction of arrow M for the movement distance p.

[0507] In short, the thrust force provided by the main assembly 2 is transmitted to the bearing element 45 (thrust force receiving part 45a) of the cartridge P through the spacing force thrust element 80. Thereby, the developing unit 9 (developing device support) rotates by θ2 (part (c) of Figure 7). Therefore, the release member 472 also rotates relative to the cartridge cover member on the drive side 424 by angle θ2.

[0508] At this time, the force receiving portion 472b of the release member 472 receives the force by engagement (contact) with the engagement portion 424s of the cover member on the revealing side 424. As a result, the release member 472 slides along the X axis of rotation to the outer position.

[0509] The cartridge cover element on the drive side 424 which is a part of the photosensitive element holder is a rotatable element that rotates relative to the release cam 472 and is an actuatable operating element on the release cam 472 to move on the release cam 472. Rotating relative to the release cam 472, the cartridge cover member on the drive side 424 moves the release cam 472 in the direction of arrow M (away from the cartridge P in the longitudinal direction of the release cam 472). revelation 6).

[0510] The engaging part 424 of the cartridge cover element on the drive side 424 functions as the thrust part on the rotating element side (thrust part on the photosensitive element holder side, thrust part on the photosensitive element side). operation) to apply force to the force receiving part on the release member side (force receiving part 472b) of the release cam 472. With rotation of the cartridge cover member 424 relative to the release cam 472, the engaging part 424s applies the force outward (outward relative to the longitudinal direction of the developing roller 6) to the force receiving part 472b.

[0511] As a result, the release member 472 moves to the external position, and drives the drive output member of the developing device 62 by the thrust portion at the free end of the cylindrical portion 472k (Figure 46).

[0512] The release member 472 moves the drive output member of the developing device 62 in the direction of arrow M to retract it to the first position (part (b) of Figure 48, Figure 53).

[0513] At this time, as shown in Figures 52 and 53, the moving distance p of the developing device drive output element 62 is greater than the amount of engagement q between the drive input element 74 and the developing device drive output element 62, and therefore, the engagement between the driving input element 74 and the developing device driving output element 62 is broken. Although the developing device driving output element 62 of the main assembly 2 continues to rotate, the driving input element 74 stops. Although the developing device driving output element 62 of the main assembly 2 continues to rotate, the driving input element 74 stops. As a result, the rotation of the developing roller gear 69 and therefore the rotation of the developing roller 6 stops.

[0514] The release element 472 and the rotational force receiving part 74b4 of the drive input part 74b (Figure 17) are projected on a phantom line parallel to the axis of rotation of the developing roller 6 when the release element 472 moves to the outside position. Next, an area of the release member 472 and an area of the rotational force receiving part 74b4 at least partially overlap. In this embodiment, the area of the drive input portion 74b is within the area of the release cam 472.

[0515] As described above, the movement distance p through which the drive output element of the developing device 62 moves from the second position to the first position by the sliding movement of the release element 472 is preferably greater than an amount of engagement q between the drive input element 74 and the drive output element of the developing device 62. That is, in the state in which the release member 472 is in the outward position (Figure 53), the release portion thrust (free end of the release element 472) of the release element 472 is preferably outside the free end of the drive input part 74b with respect to the longitudinal direction of the developing roller.

[0516] However, the end surface (free end) of the drive input portion 74b and the end surface of the release member 472 are substantially in the plane of change. Even if the position of the free end of the release member 472 is within the position of the free end of the drive input part 74b, it is sufficient that the drive force is not transmitted to the rotational force receiving part 74b4 (Figure 17) of the drive input element 74.

[0517] Previously, the drive disconnection operation for the developing roller 6 has been described in interrelation with the rotation of the developing unit 9 in the direction of arrow K. By employing such a structure, the developing roller 6 can be spaced from the drum 4 while rotating. As a result, the drive transmission to the developing roller 6 may be interrupted depending on the spacing distance between the developing roller 6 and the drum 4.

[Drive connection operation].

[0518] Description will be made as to the operation of the drive connection part when the state changes from the state in which the developing roller 6 is spaced from the drum 4 to the state in which they are in contact with each other. This operation is opposite to the operation from the contact state to the spaced developing device state described previously.

[0519] In the state of the spaced developing device (the developing unit 9 is in the angular position θ2, as shown in part (c) of Figure 7), the drive connecting part is in the state that the input input element of drive 74 and the developing device driving output element 62 are disconnected from each other, as shown in Figure 15. That is, the developing device driving output element 62 is in the first position.

[0520] When the spacing force receiving element 145 is gradually retracted from the impulse force receiving part 45a in the direction of an arrow F2, the developing unit 9 is rotated by the force of a impulse spring 95 (Figure 4 ) in the direction of an arrow H shown in Figure 7 (inverse rotation compared to the K direction described above). The release cam 472 of the developing unit 9 rotates relative to the photosensitive element holder (cartridge cover on the drive side 424).

[0521] By rotating the release cam 472 relative to the cartridge cover element on the drive side 424, the force receiving portion 472b of the release cam 472 separates from the engagement portion 424s of the cartridge cover and begins to contact the 424t hitch part.

[0522] As shown in Figure 50, the engaging part 424t is a surface inclined with respect to the axis of rotation X, and therefore the force receiving part 472b receives a reaction force comprising a component in the direction of the arrow N , through contact with the 424t coupling part. Therefore, with rotation, the release cam 472 is moved in the direction of arrow N while the force receiving part 472b is sliding in the engaging part 424t by the force received from the engaging part 424t. The engaging portion 424t functions as a thrust portion (second rotation portion, second thrust portion on the operating element side, second thrust portion on the photosensitive element holder side) to apply inward force to the receiving force 472b.

[0523] In the state where the developing unit 9 is rotated by angle θ1 (part (b) of Figure 7, Figure 52), the releasing element 472 is moved to the internal position by the reaction force received by the receiving part of force 472b from the engagement portion 424t of the cartridge cover member on the drive side 424.

[0524] With movement of the release member 472 to the internal position to separate from the developing device driving output element 62, the developing device driving output element 62 is moved to the second position by being driven by a spring (not shown) of the main assembly 2 in the direction of arrow N. Then, the drive input element 74 is engaged with the drive output element of the developing device 62, as shown in Figure 52.

[0525] Therefore, the driving force is transmitted from the main assembly 2 to the developing roller 6, thus rotating the developing roller 6. At this time, the developing roller 6 and the drum 4 are kept spaced apart from each other.

[0526] From this state, the developing unit 9 is gradually rotated in the direction of arrow H in Figure 7, through which the developing roller 6 can come into contact with the drum 4 (part (a) of Figure 7) . Also in this state, the developing device drive output element 62 is in the second position.

[0527] In the foregoing, the drive transmission operation for the developing roller 6 in interrelation with the rotation of the developing unit 9 in the direction of arrow H was described with the structure described above, the developing roller 6 is placed in contact with the drum 4 during rotation, and the driving force can be transmitted to the developing roller 6 depending on the spacing distance between the developing roller 6 and the drum 4.

[0528] The engagement portion 424t (Figures 50, 52, 53) of the cartridge cover element on the drive side 424 functions as the second thrust portion on the rotating element side (second thrust portion on the carrier side of the rotating element). photosensitive, second impulse part on the operating element side) to apply the force to the force receiving part (second force receiving part on the releasing element side) 472b of the releasing element 472. By rotating the cartridge cover on the drive side 424 relative to the release cam 472, the engaging portion 424t drives the force receiving portion 472b to move the release member 472 to the internal position.

[0529] In this embodiment, the force receiving part 472b functions both as the force receiving part (first force receiving part on the release member side) to receive the external force and as the force receiving part ( second force receiving part on the release element side) to receive the internal force.

[0530] As described above, with the structure described above, the switching between the drive disconnection and the drive transmission for the developing roller 6 can be definitively determined based on the rotation angle of the developing unit 9.

[0531] According to this embodiment, the decoupling element can be moved without using an elastic element.

[Mode 6]

[0532] Referring to Figure 54 - Figure 61, Embodiment 6 of the present invention will be described. A drive input element 574, a rolling element 545, a release element 572, a drive side cartridge cover 524 and a developing device cover element 532 of this embodiment correspond to the drive input element 74. to the rolling element 45, the release cam 72, the drive-side cartridge cover 24, and the developing device cover element 32 of Embodiment 1.

[0533] On the other hand, the arrangements, structures and functions of the drive input element 574, the rolling element 45, the release element 572, the cartridge cover on the drive side 524 and the cover element of the release device development 532 are partially different from those of the drive input element 74, the rolling element 45, the release cam 72, the drive side cartridge cover 24, and the developer device cover element 32 of Embodiment 1.

[0534] Furthermore, the release lever 73 and spring 70 are not provided in this embodiment. In the following, the detailed description will be made particularly on the different points of the previous modalities. In the description of this embodiment, the same reference numbers as Embodiments 1 and 2 are assigned to the elements that have the corresponding functions in this embodiment, and their detailed description is omitted for simplicity.

[Drive transmission for developing roller]

[0535] With reference to Figures 54 and 55, the structure of the drive connection part will be described.

[0536] The drive connecting part of this embodiment includes the drive input element 574, the release element 572, the developing device cover element 532 and the cartridge cover element on the drive side 524.

[0537] As shown in Figures 54 and 55, the drive transmission element 574 penetrates an opening 524e of the cartridge cover element on the drive side 524 and an opening 532d of the developing device cover element 532 to engage with the drive output member of the developing device 62. More particularly, as shown in Figure 54, the cartridge cover member on the drive side 524 which is a support provided on a longitudinal end portion of the cartridge is provided with openings 524e and 524d which are through openings. The developing device cover member 532 connected to the cartridge cover member on the drive side 524 includes a cylindrical part 532b which is provided with the opening 532d which is a through opening.

[0538] The shaft portion 574x of the drive input member 574 extends through the opening 532d of the cover member of the developing device 532 and the opening 524e of the cartridge cover member on the drive side 524 and the drive inlet 574b on the free end portion is exposed to the outside of the cartridge.

[0539] On the other hand, the shaft portion 572x of the release element 572 penetrates a through hole (opening) 574r provided within the drive input element 574. The through hole 574r is provided coaxially with the drive input element 574 and penetrates the drive input portion 574b. The shaft portion 572x of the release member 572 is supported so as to be slideable in the through hole 574r, and the release member 572 is reciprocated between the inner position and the outer position while the release member 572 is in the through hole 574r.

[0540] The drive input part 574b receives a rotational force through coupling with the recess 62b of the drive output element of the developing device 62. More particularly, the drive input part 574b includes a force receiving part rotational force to contact the recess 62b to receive the rotational force.

(Structure of drive connection part)

[0541] With reference to Figures 54, 55, 56, the drive connection part will be described in more detail. In the longitudinal end part of the cartridge P, the cartridge cover element on the drive side 524 is provided as a part of the cartridge holder (developer holder). The developing roller shaft is supported by bearing member 545.

[0542] The release member 572, the drive input member 574, and the developing device cover member 532 are provided in the order cited from the rolling member 545 toward the cartridge cover member on the drive side 524 ( from the inside to the outside in the longitudinal direction of the developing roller). The axes of rotation of these elements are coaxial with the axis of rotation of the drive input element 574.

[0543] Parts (a) and (b) of Figure 56 are schematic cross-sectional views of the drive connection part.

[0544] As previously described, a rising part 574p (inner surface of the cylindrical part) of the drive input element 574 and the first bearing part 545p (outer surface of the cylindrical part) of the rolling element 545 are engaged with each other. other. Furthermore, the cylindrical portion 574q of the drive input member 574 and the inner circumference 532q of the developing device cover member 532 are engaged with each other. That is, the drive input member 574 is rotatably supported by the bearing member 545 and the developing device cover member 532 on each of the opposing end portions.

[0545] Furthermore, the centers of the first rolling portion 545p (outer surface of the cylindrical portion) of the rolling element 545 and the inner circumference 532q of the cover element of the developing device 532 are coaxial with the axis of rotation X of the unit. development device 9. Outside the cover element of the developing device 532 relative to the longitudinal direction of the cartridge P, the cartridge cover element on the drive side 524 is provided.

[0546] Part (a) of Figure 56 is a schematic cross-sectional view illustrating a coupling state between the drive input portion 574b of the drive input element 574 and the recess 62b of the device drive output element 56 is a schematic cross-sectional view of the state in which the drive input portion 574b is decoupled from the recess 62b of the drive output element of the developing device 62.

[0547] Release member 572 is movable in the direction of arrow M (outside the cartridge). By moving in the direction of arrow M, the release member 572 drives the developing device driving output element 62 to move in the direction of arrow M, thereby spacing the developing device driving output element 62 from the drive input 574b. Thereby, the driving input element 574 is decoupled from the developing device driving output element 62, so that the rotational force is not transmitted from the recess 62b of the developing device driving output element 62 to the part drive input 574b.

(Release mechanism)

[0548] The release mechanism (drive disconnection mechanism) will be described. Figure 57 shows the relationship between the drive input member 574, the release member 572, and the developing device cover member 532. The release member 572 is provided with an axis portion 572x that is substantially parallel with the axis of rotation X and the force receiving part 572b extending in a direction intersecting with the axis part 572x. The force receiving portion 572b extends in a direction substantially perpendicular to the axis portion 572x (perpendicular to the X axis of rotation).

[0549] The shaft portion 572x penetrates the through hole 574r of the drive force input member 574 and the opening 545r of the bearing member 545. That is, the release member 572 is supported on opposite ends of the shaft portion 572x by the bearing element 545 and the drive force input element 574. The shaft portion 572x, the through hole 574r and the opening 545r are coaxial with the axis of rotation X. The through hole 574r is in parallel with the axis and therefore, the release member 572 is sliding relative to the through hole 574r in the direction of the X axis of rotation. In other words, the release member 572 is movable in the direction of arrow M (out of the cartridge) and in the of arrow N (into the cartridge) substantially along a line parallel to the axis of rotation of the developing roller 6.

[0550] The cylindrical part 545q of the rolling element 545 is provided with an engaging part 545h in the form of a groove. The engaging portion 545h is engaged by the force receiving portion 572b of the release member 572. The engaging portion 545h which is the groove is substantially parallel with the axis of rotation X.

[0551] Figure 58 shows the cartridge cover element on the drive side 424. The force receiving part (part to be engaged, force receiving part on the projecting part release element side) 572b of the release 572 may contact the engagement part (contact part, contact surface) 524t and the engagement part (contact part, the contact surface) 524s of the cartridge cover member on the drive side 524. coupling part 524s and coupling part 524t are inclined with respect to the axis of rotation X (inclined surface).

[Drive Disconnect Operation]

[0552] With reference to Figure 7 and Figures 58 to 61, the operation of the drive connecting part when its state changes from the state in which the developing roller 6 and the drum 4 are in contact with each other to the state in which they are spaced apart from each other. In Figures 58 to 61, some parts and structure of the release member 472 are illustrated schematically for better illustration.

[State 1]

[0553] As shown in part (a) of Figure 7, the spacing force impulse element 80 and the impulse force receiving part (spacing force receiving part) 545a of the bearing element 545 are spaced one from the other by a space d. In this case, the drum 4 and the developing roller 6 are in contact with each other. This state is called “state 1” of the spacing force impulse element 80. The state of the driving connecting part is as shown in Figure 59. In part (a) of Figure 59, the engagement part between the driving element drive input element 574 and the drive output element of the developing device 62 is illustrated schematically. Part (b) of Figure 59 is a perspective view illustrating a structure of the drive connecting part.

[0554] Between the force receiving part 572b of the release member 572 and the engaging part 524s of the cartridge cover member on the drive side 524, a space is provided. The release member 572 is in the inner position, and the drive output element of the developing device 62 is in the second position, so that the drive input part 574b of the drive input element 574 and the drive output element developing device drive 62 are engaged with each other by an engagement amount q and therefore drive transmission is enabled.

[State 2]

[0555] When the spacing force impulse element (impulse element on the main assembly side thereof) 80 moves by δ1 in the direction of arrow F1 from the drive disclosure and transmission contact state, as shown In part (b) of Figure 7, the developing unit 9 rotates around the axis of rotation X by angle θ1 in the direction of arrow K, as described previously. As a result, the developing roller 6 is spaced from the drum 4 by a distance ε1. The release element 572 and the developing device cover element 532 in the developing unit 9 rotate in the direction of arrow K by angle θ1 in interrelation with the developing unit 9.

[0556] As shown in Figure 57, the force receiving part 572b of the release element 572 that projects in the direction of the line normal to the axis of rotation X is engaged with the engaging part 545h of the rolling element 545h. Therefore, in interrelation with the rotation of the developing unit 9, the release element 572 rotates in the direction of arrow K (Figure 7).

[0557] On the other hand, when the cartridge P is mounted in the main assembly 2, the drum unit 8, the cartridge cover element on the drive side 524 and the cartridge cover element on the non-drive side 525 are fixed in place relative to the main assembly 2. Therefore, the release member 572 rotates relative to the cartridge cover member on the drive side 524. In other words, the cartridge cover on the drive side 524 rotates relative to the release member 524. release 572.

[0558] Part (a) of Figure 60 and part (b) of Figure 60 show the state of the drive connection part at this time. As shown in part (a) of Figure 60, the force receiving portion 572b of the release member 572 begins to contact the engaging portion 524 of the cartridge cover member on the drive side 524.

[0559] At this time, the release element 572 is in the inner position, and the drive output element of the developing device 62 is in the second position, and therefore the drive input element 574 and the drive output element of the developing device 62 are kept engaged with each other (part (a) of Figure 60).

[0560] Therefore, the driving force introduced into the drive input element 574 of the main assembly 2 is being transmitted to the developing roller 6 through the developing roller gear 69.

[State 3]

[0561] Part (a) of Figure 61 and part (b) of Figure 61 illustrate the drive connecting part at the moment when the thrust element on the main assembly side of the spacing force thrust element 80 moves moves from the separation drive transmission position of the developing device in the direction indicated by the arrow F1 in the figure by δ2 as shown in part (c) of Figure 7. Through the spacing impulse element 80 moving by δ2, the developing unit 9 is rotated by an angle θ2 (> θ1) by the impulse force receiving part 545a that receives the force from the spacing force impulse element 80.

[0562] In interrelation with the rotation of the developing unit 9 by the spacing force push element 80 by angle θ2, the releasing element 572 and the developing device support (developing device support 29, developing element bearing 545, developing device cover element 532) rotate in the direction indicated by arrow K in the figure.

[0563] The release member 572 rotates while the force receiving part (force receiving part on the release member side) 572b is in contact with the engagement part 524 of the cartridge cover member on the drive side 524 Therefore, the release member 572 receives the reaction force from the engaging part 524 while rotating. The engaging part 524s is a surface inclined with respect to the rotation axis

[0564] The release element 572 is sliding only in the axial direction (arrows M and N) by the engagement between the force receiving part 572b of the release element 572 and the engagement part 545h of the rolling element 545 (Figure 57) , as described above.

[0565] Therefore, the release member 572 moves outward from the cartridge P (outward in the longitudinal direction of the developing roller) by the force received by the force receiving portion 572a from the engaging portion 524s of the cover member. of cartridge on the drive side 524. When the release member 572 moves, the force receiving portion 572b slides over the engaging portion 524s of the cartridge cover member on the drive side 524.

[0566] Thus, the release member 572 rotates in the direction of arrow K (part (c) of Figure 7) relative to the cartridge cover member on the drive side 524 and slides through the movement distance p in the direction of arrow M Therefore, in interrelation with the movement of the release member 572 in the direction of arrow M, the shaft portion 572x of the release member 572 is superimposed with the drive input portion 574b of the drive input element 574 in the direction of the axis of rotation

[0567] In short, the thrust force provided by the main assembly 2 is transmitted to the bearing element 545 (thrust force receiving part 545a) of the cartridge P through the spacing force thrust element 80. Thereby, the developing unit 9 (developing device support) rotates by θ2 (part (c) of Figure 7). Therefore, the release member 572 also rotates relative to the cartridge cover member on the drive side 524 by angle θ2.

[0568] At this time, the force receiving portion 572b of the release member 572 receives the force by engagement (contact) with the engagement portion 524s of the cover member on the revealing side 524. As a result, the release member 572 slides along the X axis of rotation to the outer position.

[0569] The cartridge cover element on the drive side 524 which is a part of the photosensitive element holder functions as a rotating element that rotates relative to the release element 572 and an operating element for moving the release element 572 in relative to the drive input portion 74b acting on the release member 572. The cartridge cover member on the drive side 524 rotates relative to the release member 572 to move the release member 572 in the direction of arrow M (out of the P cartridge in the longitudinal direction of the developing roller 6).

[0570] The engagement part 524s of the cartridge cover element on the drive side 524 functions as a thrust part on the rotating element side (thrust part on the support side of the photosensitive element, thrust part of the operating element) to apply force to the force receiving portion 572b of the release member 572.

[0571] With rotation of the cartridge cover element on the drive side 524 relative to the release element 572, the engaging part 524s applies the external force (outward relative to the longitudinal direction of the developing roller 6) to the force receiving part 572b. The force receiving part 572b of the release element 572 is a force receiving part on the side of the release element (external force receiving part) for receiving the external force to drive the drive output element 62.

[0572] As a result, the release member 572 is moved to the external position and drives the drive output member of the developing device 62 on the free end portion (thrust portion) of the shaft portion 572x (Figure 57). .

[0573] The release member 572 moves the drive output member of the developing device 62 in the direction of arrow M to retract it to the first position (part (b) of Figure 56, Figure 61).

[0574] At this time, as shown in Figures 60 and 61, the movement distance p of the drive output element of the developing device 62 is greater than the amount of engagement q between the drive input element 574 and the output drive element of the developing device 62, and therefore, the engagement between the driving input element 574 and the driving output element of the developing device 62 is broken. Although the driving output element of the developing device 62 of the main assembly 2 continues to rotate, the driving input element 574 stops. As a result, the rotation of the developing roller gear 69 and therefore the rotation of the developing roller 6 stops.

[0575] The release element 572 and the rotational force receiving part (rotational force receiving part 74b4, Figure 17) of the drive input part 574b are projected on a phantom line parallel to the axis of rotation of the developing roller 6 when the release member 572 is in the external position. Next, an area of the release member 572 and an area of the rotational force receiving part 74b4 overlap at least partially. In this embodiment, the area of the drive input portion 574b is within the area of the release member 572.

[0576] The movement distance p through which the developing device drive output element 62 moves from the second position to the first position by sliding the release element 572 is preferably greater than the amount of engagement q between the drive input element 574 and the drive output element of the revealing device 62.

[0577] Therefore, the thrust part (free end part of the release element 572) of the release element 572 is outside the free end part of the drive input part 574b in the longitudinal direction of the developing roller in the state in that the release member 572 is in the external position (Figure 61). That is, the release element 572 projects externally in the longitudinal direction of the developing roller 6 beyond the drive input part 574b.

[0578] However, the free end of the release member 572 and the free end of the drive input portion 574b may be in substantially the same plane with respect to the longitudinal direction. It would be sufficient if the free end of the release member 572 is within the free end of the drive input part 574b, provided that the rotational force receiving part (rotational force receiving part 47b4, Figure 17) of the drive input part drive 574b does not receive rotational force from the drive output element of the developing device 62.

[0579] In the foregoing, the operation of the drive disconnect for the developing roller 6 in interrelation with the rotation of the developing unit 9 in the direction of arrow K has been described. By employing such a structure, the developing roller 6 can be spaced from the drum 4 while rotating. As a result, the drive transmission to the developing roller 6 may be interrupted depending on the spacing distance between the developing roller 6 and the drum 4.

[Drive connection operation]

[0580] Description will be made as to the operation of the drive connecting part when the state changes from the state in which the developing roller 6 is spaced from the drum 4 to the state in which they are in contact with each other. This operation is opposite to the operation from the contact state to the spaced developing device state described previously.

[0581] In the state of the spaced developing device (the developing unit 9 is in the angular position θ2, as shown in part (c) of Figure 7), the drive connecting part is in the state that the input element of drive 574 and the drive output element of the developing device 62 are disconnected from each other, as shown in Figure 61. That is, the drive output element of the developing device 62 is in the first position.

[0582] When the spacing force receiving element 145 is gradually retracted from the impulse force receiving part 45a in the direction of an arrow F2, the developing unit 9 is rotated by the force of a impulse spring 95 ( Figure 4) in the direction of an arrow H shown in Figure 7 (reverse rotation compared to the K direction described above). The release cam 472 of the developing unit 9 rotates relative to the photosensitive element holder (cartridge cover on the drive side 524).

[0583] By rotating the release cam 572 relative to the cartridge cover member on the drive side 524, the force receiving portion 572b of the release cam 572 separates from the engagement portion 524s of the cartridge cover and begins to contact the 524t coupling part.

[0584] As shown in Figure 58, the engaging part 524t is a surface inclined with respect to the axis of rotation , through contact with the 524t coupling part. Therefore, with rotation, the release cam 572 is moved in the direction of arrow N while the force receiving part 472b slides on the engaging part 424t by the force received from the engaging part 524t.

[0585] In the state in which the developing unit 9 is rotated by angle θ1 (part (b) of Figure 7, Figure), the releasing element 572 is moved to the internal position by the reaction force received by the receiving part of force 572b from the engaging part 524t of the cartridge cover member on the drive side 524. The force receiving part 572b functions as an internal force receiving part (second force receiving part on the release member side ) to receive the force directed into the P cartridge.

[0586] In this embodiment, the force receiving part 572b functions as both the force receiving part (first force receiving part on the release element side) to receive the external force and the force receiving part (second force receiving part on the release element side) to receive the internal force.

[0587] With movement of the release member 572 to the internal position to separate from the developing device driving output element 62, the developing device driving output element 62 is moved to the second position being driven by a spring (not shown) of the main assembly 2 in the direction of arrow N. Then, the drive input element 574 is engaged with the drive output element of the developing device 62, as shown in Figure 60.

[0588] Therefore, the driving force is transmitted from the main assembly 2 to the developing roller 6, thus rotating the developing roller 6. At this time, the developing roller 6 and the drum 4 are kept spaced apart from each other.

[0589] From this state, the developing unit 9 is gradually rotated in the direction of arrow H in Figure 7, through which the developing roller 6 can come into contact with the drum 4 (part (a) of Figure 7) . Also in this state, the drive output element of the developing device 62 is in the second position.

[0590] In the foregoing, the drive transmission operation for the developing roller 6 in interrelation with the rotation of the developing unit 9 in the direction of arrow H was described with this structure described above, the developing roller 6 is placed in contact with the drum 4 during rotation, and the driving force can be transmitted to the developing roller 6 depending on the spacing distance between the developing roller 6 and the drum 4.

[0591] The engagement portion 424t (Figures 58, 56, 61) of the cartridge cover element on the drive side 524 functions as a second thrust portion on the rotating element side (second thrust portion on the carrier side of the rotating element). photosensitive, second impulse part on the operating element side) to apply the force to the force receiving part 572b of the releasing element 572. By rotating the cartridge cover element on the driving side 524 relative to the releasing element 572, the engaging portion 524t drives the force receiving portion 572b to move the release member 572 to the internal position.

[0592] As described above, with the structure described above, the switching between the drive disconnection and the drive transmission for the developing roller 6 can be definitively determined based on the rotation angle of the developing unit 9.

[0593] According to this embodiment, the decoupling element can be moved without using an elastic element.

[0594] In this embodiment, the release element 572, as the decoupling element, penetrates the drive input element 562. In this way, in the structure in which the release element 572 is provided within the drive input element 562, the release member 572 is said to be disposed adjacent the drive input member 562.

[Mode 7]

[0595] With reference to Figure 62, Embodiment 7 will be described. In the Embodiment P process cartridge, the Embodiment 1 release lever 73 is replaced by a release lever 973.

[0596] In Embodiment 1, through the force receiving part 73b of the release lever 73 engaging with the cartridge cover element on the drive side 24, the release lever 73 rotates relative to the release cam 72 when the unit of development 9 rotates.

[0597] In this embodiment, a force receiving portion 973b of the release lever 973 engages directly with the spacing force impulse element 80 (Figure 7) to directly move the spacing force impulse element 80. The Power receiving 973b functions as an impulse power receiving part to receive impulse force from the outside (main assembly 2) of the cartridge.

[0598] When the spacing force push member 80 moves in the direction indicated by an arrow F2, the release lever 973 moves in the direction of arrow F2 to rotate relative to the release cam 72. Thereby, the release lever moves release cam 72 in the direction of arrow M to move release cam 72 to the outward position.

[0599] On the other hand, when the spacing force push member 80 moves in the direction of arrow F1, the release lever 973 moves in the direction of arrow F1 to rotate relative to the release cam 72. Thereby , the release cam 72 moves in the direction of arrow N to the inward position using the force of spring 70.

[0600] In this embodiment, the spacing force push element 80 (Figure 7) engages with the release lever 973 and does not engage with the developing device support (rolling element 45). Therefore, not all of the development unit 9 rotates. More particularly, the developing roller 6 is not spaced from the photosensitive drum 4. With the structure of this embodiment, under this condition, the release lever 72 can be moved to couple or decouple between the drive input part 74b of the input element drive 74 and the recess 62b of the drive output element of the developing device 62.

[0601] The release lever 173 in Embodiment 2 can be replaced by the release lever 973 of this embodiment.

[Mode 8]

[0602] With reference to Figure 63, Embodiment 8 will be described. Figure 63 is a perspective view of a developing cartridge in accordance with this embodiment. In the description of this embodiment, the same reference numbers as in Modality 1 are assigned to the elements that have the corresponding functions in this embodiment, and their detailed description is omitted for simplicity.

[0603] In Embodiment 1, the process cartridge P comprising the drum unit 8 and the developing unit 9 can be detachably mounted to the main assembly 2 of the image forming apparatus 1 (Figures 3 and 9).

[0604] In this embodiment, the development unit 9 itself constitutes a cartridge (development cartridge) D that can be detachably mounted to the main assembly 2.

[0605] On the other hand, the drum unit 8 (Figure 4) is attached to the main assembly 2 (cartridge tray 60, Figure 3, for example). Or, the drum unit 8 may be another cartridge (photosensitive element cartridge) that is mounted to the main assembly 2 and supported by the cartridge tray 60.

[0606] When mounting the developing cartridge D in the cartridge tray 60, a force receiving part 73b provided on the release cam 73 is engaged with the drum unit 9.

[0607] The development unit 9 of embodiments 2 to 8 may be a development cartridge D as in this embodiment.

[0608] Although the invention has been described with reference to the structures described herein, it is not limited to the details presented, and this application is intended to cover such modifications or changes as may be within the purposes of the improvements or the scope of the following claims .

Industrial applicability

[0609] In accordance with the present invention, the cartridge, the process cartridge and the image forming apparatus may be provided in which switching of the drive for the developing roller may be effected between the cartridge and the main assembly of the apparatus of image formation.

Claims (58)

1. Process cartridge (P) which can be detachably mounted to a main assembly (2) of the electrophotographic image forming apparatus (1) including a drive transmission element on the main assembly side (62) and a impulse on the side of the main assembly (80), the process cartridge (P) comprising: (i) a rotating photosensitive element (4); (ii) a rotating developing roller (6) configured to reveal a latent image formed on said photosensitive element (4), said developing roller (6) being capable of contacting and being spaced from said photosensitive element (4) ; (iii) an impulse force receiving part (45a) configured to receive an impulse force from the impulse element on the side of the main assembly (80) to space said developing roller (6) from said photosensitive element ( 4); (iv) a drive transmission element on the cartridge side (74) capable of coupling with the drive transmission element on the main assembly side (62) to receive a rotational force for rotating said developing roller (6); and characterized by the fact that it further comprises (v) a release element (72) capable of driving the drive transmission element on the main assembly side (62) to decouple said drive transmission element on the cartridge side (74 ) of the drive transmission element on the main assembly side (62) by said impulse force receiving part (45a) which receives the impulse force from the impulse element on the main assembly side (80). 2. Process cartridge (P), according to claim 1, characterized by the fact that said release element is movable between a first position in which the drive transmission element on the side of the main assembly is driven to prevent transmission of rotational force to said drive transmission element on the cartridge side from the drive transmission element on the side of the main assembly, and a second position in which transmission of a drive force from the drive transmission element drive on the main assembly side to said drive transmission element on the cartridge side. 3. Process cartridge (P) according to claim 2, characterized in that said drive transmission element on the side of the cartridge (74) is provided with a rotational force receiving part (74b3) configured to contacting a rotational force applying part (62b) of the drive transmission element on the side of the main assembly (62) to receive rotational force therefrom. 4. Process cartridge (P), according to claim 3, characterized by the fact that, according to said rotational force receiving part (74b3) and said releasing element (72) are projected on a parallel dashed line to a rotation axis of said developing roller (6), an area of said rotational force receiving part (74b3) and an area of said releasing element (72) are at least partially overlapping each other when said release element release (72) is in the first position. 5. Process cartridge (P), according to claim 4, characterized by the fact that a strip in which the area of said rotational force receiving part and the area of said releasing element are superimposed on each other on the dashed line expands by said release element which moves from the second position to the first position. 6. Process cartridge (P) according to any one of claims 3 to 5, characterized in that a free end of said releasing element is in substantially the same position as a free end of said rotational force receiving part relative to the longitudinal direction of said developing roller or in a position outside it. 7. Process cartridge (P), according to any one of claims 1 to 6, characterized by the fact that said release element moves towards an exterior of said process cartridge when said force receiving part impulse receives the impulse force from the impulse element on the side of the main assembly. 8. Process cartridge (P) according to any one of claims 1 to 7, characterized in that when said impulse force receiving part receives the impulse force from the impulse element on the side of the main assembly, said release element is moved externally in the longitudinal direction of said developing roller. 9. Process cartridge (P), according to any one of claims 1 to 8, characterized in that said release element is disposed adjacent to said drive transmission element on the side of the cartridge. 10. Process cartridge (P), according to any one of claims 1 to 9, characterized in that it additionally comprises a rotatable element (73) in relation to said release element (72), and said rotatable element moves said release element (72) in the longitudinal direction of said developing roller (6) by rotation with respect to said release element (72). 11. Process cartridge (P) for electrophotographic image formation, comprising: (i) a rotating photosensitive element (4); (ii) a rotating developing roller (6) configured to reveal a latent image formed on said photosensitive element (4), said developing roller (6) being capable of contacting and being spaced from said photosensitive element (4) ; (iii) an impulse force receiving part (45a) configured to receive an impulse force to space said developing roller (6) from said photosensitive element (4); (iv) a rotational force receiving part (74b3) configured to receive a rotational force to rotate said developing roller (6) from an exterior of said process cartridge (P); and characterized by the fact that it further comprises (v) a movable element (72), movable with respect to the rotational force receiving part (74b3) at least in a longitudinal direction of said developing roller (6), said movable element (72) being externally movable in the longitudinal direction by said impulse force receiving part receiving the impulse force (45a), wherein, when said movable element (72) moves externally longitudinally, at least a part thereof is exposed to the outside of said process cartridge (P). 12. Process cartridge (P), according to claim 11, characterized by the fact that said movable element is arranged adjacent to said rotational force receiving part. 13. Process cartridge (P), according to claim 11 or 12, characterized by the fact that said movable element moves between a first position in which it is substantially in the same position or outside a free end of said part of receiving rotational force in the longitudinal direction, and a second position in which said movable element is retracted inwardly from said first position in the longitudinal direction, and wherein said movable element is moved from the second position to the first position by the said impulse force receiving part that receives the impulse force. 14. Process cartridge (P), according to any one of claims 11 to 13, characterized by the fact that said movable element moves between a first position in which said impulse force receiving part receives the force and a second position which is within the first position, wherein as said movable element and said rotational force receiving part are projected on a dashed line parallel with an axis of rotation of said developing roller when said movable element is in the first position, an area of said movable element and an area of said rotational force receiving part are at least partially overlapping each other. 15. Process cartridge (P), according to claim 14, characterized by the fact that by said movable element moving from the second position to the first position, a range in which the area of said movable element and the area of the said rotational force receiving part are superimposed on each other in the dashed line expands. 16. Process cartridge (P), according to any one of claims 11 to 15, characterized in that it additionally comprises a drive input element (74) rotatable by said rotational force receiving part (74b3) which receives the rotational force, wherein said rotational force receiving part (74b3) is provided at an end part of said drive input element (74). 17. Process cartridge (P) according to claim 16, characterized in that a projection provided on an end part (74b) of said drive input element (74) is provided with said receiving part of rotational force (74b3). 18. Process cartridge (P), according to any one of claims 11 to 17, characterized in that it additionally comprises a photosensitive element support (26) that rotatably supports said photosensitive element (4), wherein a rotatable developing device support (29) rotatably supports said developing roller (6), said developing device support (29) rotatable with respect to said photosensitive element (26), when an axis of rotation of said part receiving rotational force (74b3) is substantially coaxial with a center of rotation of said developing device support (29) relative to said photosensitive element support (26). 19. Process cartridge (P), according to any one of claims 11 to 18, characterized by the fact that said movable element moves towards an exterior of said process cartridge in response to receiving the impulse force by the said impulse force receiving part. 20. Process cartridge (P), according to any one of claims 11 to 19, characterized by the fact that it additionally comprises a rotating element (73), rotatable with respect to said movable element (72) in response to receiving the force of impulse by said impulse force receiving part (45a), wherein said rotating element (73) moves said movable element (72) in the longitudinal direction of said developing roller (6) by rotation relative to said element mobile (72). 21. Process cartridge (P), according to any one of claims 11 to 19, characterized in that it additionally comprises a rotatable element (73), rotatable with respect to said movable element (72), and said rotatable element (73) moves said movable element (72) in the longitudinal direction of said developing roller (6) by rotation relative to said movable element (72). 22. Process cartridge (P), according to any one of claims 11 to 21, characterized by the fact that said movable element is movable substantially in parallel with the rotational axis of said developing roller. 23. Process cartridge (P) detachably mountable to a main assembly (2) of the electrophotographic image forming apparatus (1) including a drive transmission element on the side of the main assembly (62), said process cartridge (P) comprising: (i) a photosensitive element (4); (ii) a photosensitive element support (26) that rotatably supports said photosensitive element (4); (iii) a developing roller (6) configured to reveal a latent image formed on said photosensitive element (4); (iv) a developing device support (29) rotatably supporting said developing roller (6), said developing device support (29) being movable with respect to said photosensitive element support (26); (v) a drive transmission element on the cartridge side (74) capable of coupling with the drive transmission element on the main assembly side (62) to receive a rotational force for rotating said developing roller (6); and characterized by the fact that it further comprises (vi) a release element (72) capable of pushing the drive transmission element on the main assembly side (62) to decouple said drive transmission element from the cartridge side (74 ) of the drive transmission element on the side of the main assembly (62) by movement of said developing device support (29) relative to said photosensitive element support (26). 24. Process cartridge (P), according to claim 23, characterized by the fact that said release element is movable between a first position in which the drive transmission element on the side of the main assembly is driven to prevent transmission of rotational force to said drive transmission element on the cartridge side from the drive transmission element on the side of the main assembly, and a second position in which transmission of a drive force from the drive transmission element drive on the main assembly side to said drive transmission element on the cartridge side. 25. Process cartridge (P) according to claim 24, characterized in that said drive transmission element on the side of the cartridge is provided with a rotational force receiving part configured to contact a of applying rotational force from the drive transmission element on the side of the main assembly to receive rotational force therefrom. 26. Process cartridge (P), according to claim 25, characterized by the fact that a free end of said releasing element is in substantially the same position as a free end of said rotational force receiving part with respect to the direction longitudinal of said developing roller or in an external position. 27. Process cartridge (P) for electrophotographic image formation, comprising: (i) a photosensitive element (4); (ii) a photosensitive element support (26) rotatably supporting said photosensitive element (4); (iii) a developing roller (6) configured to reveal a latent image formed on said photosensitive element (4); (iv) a developing device support (29) rotatably supporting said developing roller (6), said developing device support (29) being movable with respect to said photosensitive element support (26); (v) a rotational force receiving part (74b3) configured to receive a rotational force to rotate said developing roller (6) from an exterior of said process cartridge (P); and characterized by the fact that it further comprises (vi) a movable element (72), movable with respect to said rotational force receiving part (74b3) at least in a longitudinal direction of said developing roller (6), said element movable (72) being externally movable in the longitudinal direction by such movement of said developing device support (29) that said developing roller (6) is moved away from said photosensitive element (4), wherein, when said movable element (72) moves longitudinally externally, at least a part of it is exposed to the outside of said process cartridge (P). 28. Process cartridge (P), according to claim 27, characterized by the fact that said movable element is disposed adjacent to said rotational force receiving part. 29. Process cartridge (P), according to any of claim 27 or 28, characterized by the fact that said movable element is moved between a first position in which it is substantially in the same position or outside a free end of said rotational force receiving part in the longitudinal direction, and a second position in which said movable element is retracted into said first position in the longitudinal direction, and wherein said movable element is moved from the second position to the first position by said support of rotating developing device in relation to said photosensitive element support. 30. Process cartridge (P), according to any one of claims 27 to 29, characterized by the fact that said movable element is moved between a first position that is longitudinally outside and a second position that is longitudinally inside the first position , and wherein, as said movable element and said rotational force receiving part are projected on a dashed line parallel to the axis of rotation of said developing roller when said movable element is in the first position, an area of said movable element and an area of said rotational force receiving part are partially overlapped on the dashed line. 31. Process cartridge (P), according to claim 30, characterized by the fact that through said movable element that moves from the second position to the first position, a range in which the area of said movable element and the area of said rotational force receiving part are superimposed on each other in the dashed line expands. 32. Process cartridge (P), according to any one of claims 27 to 31, characterized in that it additionally comprises a drive input element (74) rotating by said rotational force receiving part (74b3) which receives the rotational force, wherein said rotational force receiving part (74b3) is provided in an end part (74b) of said drive input element (74). 33. Process cartridge (P), according to claim 32, characterized by the fact that a projection provided on the end part (74b) of said drive input element (74) is provided with said receiving part of rotational force (74b3). 34. Electrophotographic image forming apparatus (1), characterized by comprising: a main assembly (2) of said electrophotographic image forming apparatus (1); and a process cartridge (P) as defined in any one of claims 1 to 33, wherein said cartridge (P) is detachably mounted to said main assembly (2). 35. Developing cartridge (D) detachably mountable to a main assembly (2) of the electrophotographic image forming apparatus (1) including a drive transmission element on the side of the main assembly (62), an element impulse on the side of the main assembly (80) and a rotating photosensitive element (4), comprising: (i) a rotating developing roller (6) configured to reveal a latent image formed in said photosensitive element (4); (ii) an impulse force receiving part (45a) configured to receive impulse force from the impulse element on the side of the main assembly (80); (iii) a drive transmission element on the cartridge side (74) capable of coupling with the drive transmission element on the main assembly side (60) to receive a rotational force to rotate said developing roller (6); and characterized by the fact that it further comprises (iv) a release element (72) capable of driving the drive transmission element on the main assembly side (62) to decouple said drive transmission element on the cartridge side (74 ) of the drive transmission element on the main assembly side (62) by said impulse force receiving part (45a) which receives the impulse force from the impulse element on the main assembly side (80). 36. Developing cartridge (D), according to claim 35, characterized by the fact that said release element (72) is movable between a first position in which the drive transmission element on the side of the main assembly (62 ) is driven to prevent the transmission of rotational force to said drive transmission element on the cartridge side (74) from the drive transmission element on the side of the main assembly (62), and a second position in which the transmission of a driving force from the drive transmission element on the main assembly side (62) to said drive transmission element on the cartridge side (74). 37. Developing cartridge (D) according to claim 36, characterized in that said drive transmission element on the side of the cartridge (74) is provided with a rotational force receiving part (74b3) configured to contacting a rotational force applying part (62b) of the drive transmission element on the side of the main assembly (62) to receive the rotational force therefrom. 38. Developing cartridge (D), according to claim 37, characterized by the fact that, as said rotational force receiving part and said releasing element are projected in a dashed line parallel with an axis of rotation of the said developing roller, an area of said rotational force receiving part and an area of said releasing element are at least partially overlapping each other when said releasing element is in the first position. 39. Developing cartridge (D), according to claim 38, characterized by the fact that a strip in which the area of said rotational force receiving part and the area of said releasing element are superimposed on each other on the dashed line expands by said release element which moves from the second position to the first position. 40. Developing cartridge (D), according to any one of claims 37 to 39, characterized by the fact that a free end of said releasing element is in substantially the same position as a free end of said rotational force receiving part in relation to the longitudinal direction of said developing roller or in an external position thereof. 41. Developing cartridge (D), according to any one of claims 35 to 40, characterized by the fact that said release element moves towards an exterior of said process cartridge when said force receiving part impulse receives the impulse force from the impulse element on the side of the main assembly. 42. Developing cartridge (D), according to any one of claims 35 to 41, characterized by the fact that, when said impulse force receiving part receives the impulse force from the impulse element on the side of the main assembly, said release element is moved externally in the longitudinal direction of said developing roller. 43. Developing cartridge (D), according to any one of claims 35 to 42, characterized by the fact that said release element is disposed adjacent to said drive transmission element on the side of the cartridge. 44. Developing cartridge (D), according to any one of claims 35 to 43, characterized in that it additionally comprises a frame rotatably supporting said developing roller, and a lever provided with said force receiving part. thrust, wherein said lever is movable relative to said frame in response to receipt of said thrust force by said thrust force receiving part. 45. Developing cartridge (D), according to any one of claims 35 to 44, characterized in that it additionally comprises a photosensitive drum. 46. Developing cartridge (D) for electrophotographic image formation, comprising: (i) a rotating developing roller (6) configured to develop a latent image formed on a photosensitive drum which is provided on an exterior of said developing cartridge ( D); (ii) a rotational force receiving part (74b3) configured to receive a rotational force to rotate said developing roller (6) from an exterior of said cartridge; (iii) an impulse force receiving part (45a) configured to receive an impulse force from the outside of said developing cartridge (D); and characterized by the fact that it further comprises (iv) a movable element (72), movable with respect to the rotational force receiving part (74b3) at least in a longitudinal direction of said developing roller (6), said movable element (72) being externally movable in the longitudinal direction by said impulse force receiving part (45a) which receives the impulse force, wherein, when said movable element (72) moves externally longitudinally, at least a part thereof is exposed to the outside of said process cartridge. 47. Developing cartridge (D), according to claim 46, characterized by the fact that said movable element is disposed adjacent to said rotational force receiving part. 48. Developing cartridge (D), according to any one of claims 46 or 47, characterized by the fact that said movable element is moved between a first position in which it is substantially in the same position or outside a free end of said rotational force receiving part in the longitudinal direction, and a second position in which said movable element is retracted into said first position in the longitudinal direction, and in which said movable element is moved from the second position to the first position by said impulse force receiving part that receives the impulse force. 49. Developing cartridge (D), according to any one of claims 46 to 48, characterized by the fact that said movable element is moved between a first position that is longitudinally outside and a second position that is inside the first position, wherein as said movable element and said rotational force receiving part are projected on a dashed line parallel with an axis of rotation of said developing roller when said movable element is in the first position, an area of said movable element and an area of said rotational force receiving part are at least partially overlapping each other. 50. Developing cartridge (D), according to claim 49, characterized by the fact that through said movable element moving from the second position to the first position, a range in which the area of said movable element and the area of the said rotational force receiving part are superimposed on each other in the dashed line expands. 51. Developing cartridge (D), according to any one of claims 46 to 50, characterized in that it additionally comprises a rotary drive input element by said rotational force receiving part that receives the rotational force, wherein said rotational force receiving part is provided at an end part of said drive input element. 52. Developing cartridge (D) according to claim 51, characterized in that a projection provided on an end part of said drive input element is provided with said rotational force receiving part. 53. Developing cartridge (D), according to any one of claims 46 to 52, characterized by the fact that said movable element moves towards an exterior of said cartridge in response to receiving the impulse force by said part receiving impulse force. 54. Developing cartridge (D), according to any one of claims 46 to 53, characterized by the fact that it additionally comprises a rotatable element, rotatable with respect to said release element in response to receipt of the impulse force by said part of receiving impulse force, wherein said rotating element moves said movable element in the longitudinal direction of said developing roller by rotation relative to said releasing element. 55. Developing cartridge (D), according to any one of claims 46 to 54, characterized by the fact that said movable element is movable substantially in parallel with the rotational axis of said developing roller. 56. Developing cartridge (D), according to any one of claims 46 to 55, characterized in that it additionally comprises a frame rotatably supporting said developing roller, and a lever provided with said force receiving part. thrust, wherein said lever is movable relative to said frame in response to receipt of said thrust force by said thrust force receiving part. 57. Developing cartridge (D), according to any one of claims 46 to 55, characterized in that it additionally comprises a photosensitive drum. 58. Electrophotographic image forming apparatus (1), characterized by comprising: main assembly (2) of said electrophotographic image forming apparatus (1); and a developing cartridge (D) as defined in any one of claims 35 to 57, wherein said developing cartridge (D) is detachably mounted to said main assembly.