Cartridge, drum unit, and image forming apparatus

Abstract

10 15 20 26 24 91 27 12 O ct 2 02 6 2 0 2 6 2 4 9 1 2 7 1 2 O c t 2 0 2 6 A B S T R A C T 1 0

Description

TITLE OF THE INVENTION: CARTRIDGE, DRUM UNIT AND IMAGE FORMING APPARATUS [RELATED APPLICATION]

[0001] This application is a divisional application of Australian Patent Application No. 2024287264, in turn a divisional application of Australian Patent Application No. 2021345939, a national phase entry of International Patent Application No. PCT / JP2021 / 035213, filed 16 September 2021. The contents of Australian Patent Application Nos. 2024287264, 2021345939 are incorporated herein in their entirety. [FIELD OF THE INVENTION] [0001a] The present invention relates to an electrophotographic image forming apparatus such as a copying machine or a printer which employs an electrophotographic method, and a cartridge usable with the electrophotographic image forming apparatus. The present invention also relates to a drum unit usable with the electrophotographic image forming apparatus and the cartridge.

[0002] Here, the electrophotographic image forming apparatus (hereinafter, also referred to as an "image forming apparatus") is an apparatus which forms an image on a recording material by using the electrophotographic image forming method. Examples of the image forming apparatus include a copying machine, a facsimile machine, a printer (laser beam printer, LED printer, and so on), a multifunction printer of them, and the like.

[0003] The cartridge is dismountable from the main assembly of the image forming apparatus (apparatus main assembly). Examples of the cartridge include a process cartridge in which a photosensitive member and at least one of the process means acting on the photosensitive member is integrally formed into a cartridge.

[0004] The drum unit is a unit including a photosensitive drum, and is used for the cartridge or the image forming apparatus. [Background Art] 2026249127   12 Oct 2026

[0005] Conventionally, in the field of the image forming apparatus using the electrophotographic forming process, it is known that an electrophotographic photosensitive member (hereinafter referred to as a photosensitive drum) and a process means acting on the photosensitive drum are integrally formed into a cartridge. Such a cartridge is dismountable from the main assembly of the image forming apparatus.

[0006] According to this cartridge method, the maintenance of the image forming apparatus can be performed by the user himself / herself without relying on a service person, so that the maintainability can be remarkably improved. Therefore, this cartridge type is widely used in an image forming apparatus.

[0007] In a structure in which the cartridge can be mounted to and dismounted from the image forming apparatus main assembly (device main assembly), there is a structure in which the main assembly and the cartridge are connected by using a coupling to input a driving force from the device main assembly to the cartridge (JP H8-328449).

[0008] The amount of torque required to drive the cartridge varies depending on the structure of the cartridge.

[0009] JP 2002-202690 proposes a structure of a cartridge including a load generating member which applies a load to the rotation of the photosensitive drum. The load generating member stabilizes the rotation of the photosensitive drum by increasing the torque of the photosensitive drum (JP 2002- 202690). [SUMMARY] [0009a] It is an object of the present invention to substantially overcome, or at least ameliorate, at least one disadvantage of present arrangements. [0009b] One aspect of the present disclosure provides a cartridge detachably mountable to a main assembly of an image forming apparatus, the cartridge comprising: a photosensitive drum; a casing having a first end portion and a second end portion opposite from the first end portion in an axial direction of the photosensitive drum, the casing rotatably supporting the photosensitive drum; and a coupling operatively connected to the photosensitive drum so as to be capable of transmitting a driving force toward the photosensitive drum, the coupling being positioned adjacent to the first end portion of the casing, wherein the coupling includes: a main body, and a movable portion movable relative to the main body of the coupling between a first position 2026249127   12 Oct 2026 and a second position, wherein the movable portion is closer to the second end portion of the casing in the axial direction of the photosensitive drum when the movable portion is in the second position than when the movable portion is in the first position, wherein the coupling further includes a projection configured to move in the circumferential direction of the coupling and downstream in a rotational movement direction of the coupling by not less than 20° relative to the main body of the coupling in response to movement of the movable portion from the first position to the second position, the projection projects so as to be away from an axis of the coupling, and the projection has an acting portion configured to abut on a braking force applying member provided in the main assembly for applying a braking force to the coupling and move the braking force applying member downstream in the rotational movement direction of the coupling relative to a driving force applying member provided in the main assembly for applying the driving force to the coupling. [0009c] Another aspect of the present disclosure provides a cartridge detachably mountable to a main assembly of an image forming apparatus, the main assembly including a driving force application member and a braking force application member, the cartridge comprising: a photosensitive drum; and a coupling operatively connected to the photosensitive drum so as to be capable of transmitting a driving force toward the photosensitive drum, wherein the coupling includes, a main body, and a movable member movable relative to the main body of the coupling, wherein the movable member is provided with an engaging portion configured to be entered between the driving force application member and the braking force application member by movement thereof relative to the main body of the coupling, wherein the movable member is configured to receive the driving force from the driving force application member and to receive a braking force for applying a load against rotation of the coupling, from the braking force application member, and 2026249127   12 Oct 2026 wherein the coupling further includes an operating portion, wherein the engaging portion is configured to move in response to movement of the operating portion, wherein the coupling is provided on a first side of the cartridge in the axial direction of the photosensitive drum, and the engaging portion is configured to move toward a downstream side in a rotational movement direction of the coupling in response to movement of the operating portion toward a second side opposite from the first side. [0009d] Another aspect of the present disclosure provides a drum unit usable for a cartridge which is detachably mountable to a main assembly of an image forming apparatus, the main assembly including a driving force application member and a braking force application member, the drum unit comprising: a photosensitive drum; and a coupling operatively connected to the photosensitive drum so as to be capable of transmitting a driving force toward the photosensitive drum, wherein the coupling includes: a main body, and a movable member movable relative to the main body of the coupling, wherein the movable member is provided with an engaging portion configured to be entered between the driving force application member and the braking force application member by movement thereof relative to the main body of the coupling, wherein the movable member is configured to receive the driving force from the driving force application member and to receive a braking force for applying a load against rotation of the coupling, from the braking force application member, and wherein the coupling further includes an operating portion, wherein the engaging portion is configured to move in response to movement of the operating portion, wherein the coupling is provided on a first side of the cartridge in the axial direction of the photosensitive drum, and the engaging portion is configured to move toward a downstream side in a rotational movement direction of the coupling in response to 2026249127   12 Oct 2026 movement of the operating portion toward a second side opposite from the first side.

[0010] The object of some embodiments of the present invention is to further develop the above-mentioned conventional technology. 2026249127   12 Oct 2026

[0011] An exemplary structure disclosed here is a cartridge detachably mountable to a main assembly of an image forming apparatus, the main assembly including a driving force application member a braking force application member, the cartridge comprising: 5         a photosensitive drum; and a coupling operatively connected to the photosensitive drum so as to be capable of transmitting a driving force toward the photosensitive drum, wherein the coupling includes, a main body, and 10         a movable member movable relative to the main body of the coupling, wherein the movable member is provided with an engaging portion configured to be entered between the driving force application member and the braking force application member by movement thereof relative to the main body of the coupling, and 15         wherein the movable member is configured to receive the driving force from the driving force application member and to receive a braking force for applying a load against rotation of the coupling, from the braking force application member.

[0012] Another exemplary structure disclosed here is a cartridge detachably 20 mountable to a main assembly of an image forming apparatus, the main assembly including a driving force application member, and a braking force application member movable relative to the driving force application member and configured to apply a load against rotation of the driving force application member, the cartridge comprising: 25         a photosensitive drum; and a coupling operatively connected to the photosensitive drum so as to be capable of transmitting a driving force toward the photosensitive drum, 2026249127   12 Oct 2026 wherein the coupling is provided with an engaging portion configured to engage with the braking force application member to receive the driving force from the driving force application member by way of the braking force application member. 5

[0013] A further exemplary structure disclosed here is a cartridge comprising: a photosensitive drum; a casing having a first end portion and a second end portion opposite from the first end portion in an axial direction of the photosensitive drum, the casing rotatably supporting the photosensitive drum; and 10         a coupling operatively connected to the photosensitive drum so as to be capable of transmitting a driving force toward the photosensitive drum, wherein the coupling includes, a main body, a movable portion movable relative to the main body of the coupling 15 between a first position and a second position, wherein the movable portion is closer to the second end portion of the casing in the axial direction of the photosensitive drum when the movable portion is in the second position than when the movable portion is in the first position, and a projection configured to move in a circumferential direction of the 20 coupling relative to the main body of the coupling in response to movement of the movable portion from the first position to the second position.

[0014] A further exemplary structure disclosed here is a cartridge comprising: a photosensitive drum; a casing having a first end portion and a second end portion opposite from 25 the first end portion in an axial direction of the photosensitive drum, the casing rotatably supporting the photosensitive drum; and a coupling operatively connected to the photosensitive drum so as to be 2026249127   12 Oct 2026 capable of transmitting a driving force toward the photosensitive drum, wherein the coupling includes, a main body, a movable portion movable relative to the main body of the coupling 5 between a first position and a second position, wherein the movable portion is closer to the second end portion of the casing in the axial direction of the photosensitive drum when the movable portion is in the second position than when the movable portion is in the first position, and a projection configured to move away from an axis of the coupling relative 10 to the main body of the coupling in response to movement of the movable portion from the first position to the second position.

[0015] A further exemplary structure disclosed here is a cartridge comprising: a photosensitive drum; a casing having a first end portion and a second end portion opposite from 15 the first end portion in an axial direction of the photosensitive drum, the casing rotatably supporting the photosensitive drum; and a coupling operatively connected to the photosensitive drum so as to be capable of transmitting a driving force toward the photosensitive drum, wherein the coupling includes, 20           a first wall, a second wall provided inside the first wall in a radial direction of the coupling, a groove portion defined by the first wall and the second wall, a recessed portion provided in the second wall, and 25          an inclined portion adjacent the recessed portion, wherein at least a part of the inclined portion is more remote from an axis of the coupling than the recessed portion, 2026249127   12 Oct 2026 wherein one of the sides of the recessed portion in a circumferential direction of the coupling is opened, and on the other side of the recessed portion in the circumferential direction, at lease a part of the inclined portion is provided, and 5         wherein the inclined portion is inclined so as to go away from the second end portion of the casing in the axial direction of the photosensitive drum as goes away from the recessed portion in the circumferential direction.

[0016] A further exemplary structure disclosed here is a cartridge comprising: a photosensitive drum; 10         a casing having a first end portion and a second end portion opposite from the first end portion in an axial direction of the photosensitive drum, the casing rotatably supporting the photosensitive drum; and a coupling operatively connected to the photosensitive drum so as to be capable of transmitting a driving force toward the photosensitive drum, 15         wherein the coupling includes, a base portion extending in the axial direction of the coupling, a first projection having a circular column shape and projecting outwardly from the base portion in a radial direction of the coupling, and a second projection having a circular column shape and projecting 20 outwardly from the base portion in a radial direction of the coupling, wherein in the radial direction of the coupling, a distance from an axis of the coupling to an outermost edge portion of the first projection is shorter than a distance from the axis of the coupling to an outermost edge portion of the second projection, 25          wherein as viewed in the axial direction of the coupling, a direction in which the first projection projects from the base portion is different from a direction in which the second projection extends from the base portion, and 2026249127   12 Oct 2026 wherein in axial direction axial direction of the coupling, the first projection is disposed at a position more remote from the second end portion of the casing than the second projection.

[0017] A further exemplary structure disclosed here is an is an image forming 5 apparatus including the apparatus main assembly of the image forming apparatus and, any one of the above-mentioned cartridges.

[0018] A further exemplary structure disclosed here is a drum unit usable for a cartridge which is detachably mountable to a main assembly of an image forming apparatus, the main assembly including a driving force application member and a 10 braking force application member, the drum unit comprising: a photosensitive drum; and a coupling operatively connected to the photosensitive drum so as to be capable of transmitting a driving force toward the photosensitive drum, wherein the coupling includes, 15        a main body, and a movable member movable relative to the main body of the coupling, wherein the movable member is provided with an engaging portion configured to be entered between the driving force application member and the braking force application member by movement thereof relative to the main body 20 of the coupling, and wherein the movable member is configured to receive the driving force from the driving force application member and to receive a braking force for applying a load against rotation of the coupling, from the braking force application member. 25

[0019] A further exemplary structure disclosed here is a drum unit usable for a cartridge detachably mountable to a main assembly of an image forming apparatus, the main assembly including a driving force application member, and a 2026249127   12 Oct 2026 braking force application member movable relative to the driving force application member and configured to apply a load against rotation of the driving force application member, the drum unit comprising: a photosensitive drum; and 5         a coupling operatively connected to the photosensitive drum so as to be capable of transmitting a driving force toward the photosensitive drum, wherein the coupling is provided with an engaging portion configured to engage with the braking force application member to receive the driving force from the driving force application member by way of the braking force 10 application member.

[0020] A further exemplary structure disclosed here is a drum unit usable for a cartridge, the drum unit comprising: a photosensitive drum having a first end portion and a second end portion opposite from the first end portion; and 15         a coupling operatively connected to the photosensitive drum so as to be capable of transmitting a driving force toward the photosensitive drum, wherein the coupling includes, a main body, a movable portion movable relative to the main body of the coupling 20 between a first position and a second position, wherein the movable portion is closer to the second end portion of the photosensitive drum in the axial direction of the photosensitive drum when the movable portion is in the second position than when the movable portion is in the first position, and a projection configured to move in a circumferential direction of the 25 coupling relative to the main body of the coupling in response to movement of the movable portion from the first position to the second position.

[0021] A further exemplary structure disclosed here is a drum unit usable for a 2026249127   12 Oct 2026 cartridge, the drum unit comprising: a photosensitive drum having a first end portion and a second end portion opposite from the first end portion; and a coupling operatively connected to the photosensitive drum so as to be 5 capable of transmitting a driving force toward the photosensitive drum, wherein the coupling includes, a main body, a movable portion movable relative to the main body of the coupling between a first position and a second position, wherein the movable portion is 10 closer to the second end portion of the photosensitive drum in the axial direction of the photosensitive drum when the movable portion is in the second position than when the movable portion is in the first position, and a projection configured to move away from an axis of the coupling relative to the main body of the coupling in response to movement of the movable portion 15 from the first position to the second position.

[0022] A further exemplary structure disclosed here is a drum unit usable for a cartridge, the drum unit comprising: a photosensitive drum having a first end portion and a second end portion opposite from the first end portion; and 20         a coupling operatively connected to the photosensitive drum so as to be capable of transmitting a driving force toward the photosensitive drum, wherein the coupling includes, a first wall, a second wall provided inside the first wall in a radial direction of the 25 coupling, a groove portion defined by the first wall and the second wall, a recessed portion provided in the second wall, and 2026249127   12 Oct 2026 an inclined portion adjacent the recessed portion, wherein at least a part of the inclined portion is more remote from an axis of the coupling than the recessed portion, wherein one of the sides of the recessed portion in a circumferential 5 direction of the coupling is opened, and on the other side of the recessed portion in the circumferential direction, at lease a part of the inclined portion is provided, and wherein the inclined portion is inclined so as to go away from the second end portion of the photosensitive drum in the axial direction of the photosensitive 10 drum as goes away from the recessed portion in the circumferential direction.

[0023] A further exemplary structure disclosed here is a drum unit usable for a cartridge, the drum unit comprising: a photosensitive drum having a first end portion and a second end portion opposite from the first end portion; and 15         a coupling operatively connected to the photosensitive drum so as to be capable of transmitting a driving force toward the photosensitive drum, wherein the coupling includes, a base portion extending in the axial direction of the coupling, a first projection having a circular column shape and projecting outwardly 20 from the base portion in a radial direction of the coupling, and a second projection having a circular column shape and projecting outwardly from the base portion in a radial direction of the coupling, wherein in the radial direction of the coupling, a distance from an axis of the coupling to an outermost edge portion of the first projection is shorter than a 25 distance from the axis of the coupling to an outermost edge portion of the second projection, wherein as viewed in the axial direction of the coupling, a direction in 2026249127   12 Oct 2026 which the first projection projects from the base portion is different from a direction in which the second projection extends from the base portion, and wherein in axial direction axial direction of the coupling, the first projection is disposed at a position more remote from the second end portion of the photosensitive drum than the second projection.

[0024] Conventional technology can be developed according to some embodiments. [BRIEF DESCRIPTION OF THE DRAWINGS]

[0025] Figure 1 is a perspective view of a drum coupling 143.

[0026] Figure 2 is a schematic sectional view of an image forming apparatus.

[0027] Figure 3 is a sectional view of a process cartridge.

[0028] Figure 4 is a sectional view of the image forming apparatus.

[0029] Figure 5 is a sectional view of the image forming apparatus.

[0030] Figure 6 is a sectional view of the image forming apparatus.

[0031] Figure 7 is a partial detailed view of the tray.

[0032] Figure 8 is a perspective view of the storing element pressing unit and the cartridge pressing unit.

[0033] Figure 9 is a partial perspective view of the image forming apparatus.

[0034] Figure 10 is a side view (partial sectional view) of the process cartridge.

[0035] Figure 11 is a sectional view of the image forming apparatus.

[0036] Figure 12 is a perspective view of a development separation control unit.

[0037] Figure 13 is an assembly perspective view of the process cartridge.

[0038] Figure 14 is a perspective view of the process cartridge.

[0039] Figure 15 is an assembly perspective view of the process cartridge.

[0040] Figure 16 is an assembly perspective view of the process cartridge. 2026249127   12 Oct 2026

[0041] Figure 17 is a view of a separation holding member R per se.

[0042] Figure 18 is a view of a force applying member R per se.

[0043] Figure 19 is a partial sectional view of the separation holding member R after assembly. 5

[0044] Figure 20 is an enlarged view of the periphery of the separation holding member R.

[0045] Figure 21 is an enlarged view of the periphery of the separation holding member R.

[0046] Figure 22 is a bottom view of a driving side of the process cartridge. 10

[0047] Figure 23 is an illustration showing operation of a developing unit in the main assembly of the image forming apparatus.

[0048] Figure 24 is an illustration showing operation of the developing unit in the main assembly of the image forming apparatus.

[0049] Figure 25 is an illustration showing the operation of the developing 15 unit in the main assembly of the image forming apparatus.

[0050] Figure 26 is an illustration showing the operation of the developing unit in the main assembly of the image forming apparatus.

[0051] Figure 27 is an illustration showing the operation of the developing unit in the main assembly of the image forming apparatus. 20

[0052] Figure 28 is a view of the separation holding member L per se.

[0053] Figure 29 is a view of the force applying member L per se.

[0054] Figure 30 is an assembly perspective view after assembling the development pressure spring and assembling the separation holding member L.

[0055] Figure 31 is a partial sectional view of the separation holding member 25 L after assembly.

[0056] Figure 32 is an enlarged view of the peripheries of the separation holding member L and the force applying member L. 2026249127   12 Oct 2026

[0057] Figure 33 is an enlarged view of the periphery of the separation holding member.

[0058] Figure 34 is a side view as viewed from the driving side with the process cartridge mounted inside the image forming apparatus main assembly. 5

[0059] Figure 35 is an illustration showing a process cartridge in the main assembly of the image forming apparatus.

[0060] Figure 36 is an illustration showing the operation of the developing unit in the main assembly of the image forming apparatus.

[0061] Figure 37 is an illustration showing the operation of the developing 10 unit in the main assembly of the image forming apparatus.

[0062] Figure 38 is an illustration showing the operation of the developing unit in the main assembly of the image forming apparatus.

[0063] Figure 39 is an illustration showing the operation of the developing unit in the main assembly of the image forming apparatus. 15

[0064] Figure 40 is an illustration showing the arrangement of the separation holding member R and the force applying member.

[0065] Figure 41 is an illustration showing the arrangement of the separation holding member and the force applying member.

[0066] Figure 42 is a side view as viewed from the driving side with the 20 process cartridge 100 mounted inside the image forming apparatus main assembly.

[0067] Figure 43 is an exploded perspective view of the drive transmission unit 203.

[0068] Figure 44 is a sectional view of the drive transmission unit 203. 25

[0069] Figure 45 is a perspective view of the drive transmission unit 203.

[0070] Figure 46 is a sectional perspective view of the main assembly of the device including the drive transmission unit 203. 2026249127   12 Oct 2026

[0071] Figure 47 is a front view of the drive transmission unit 203 and the drum coupling 143.

[0072] Figure 48 is a developed view illustrating engagement of the drum coupling. 5

[0073] Figure 49 is a developed view illustrating the engagement of the drum coupling.

[0074] Figure 50 is a developed view illustrating the engagement of the drum coupling.

[0075] Figure 51 is a sectional view illustrating the engagement of the drum 10 coupling.

[0076] Figure 52 is a perspective view illustrating a modified example of the drum coupling.

[0077] Figure 53 is a developed view illustrating the engagement of the drum coupling. 15

[0078] Figure 54 is a development view illustrating the engagement of the drum coupling.

[0079] Figure 55 is a perspective view of the drum unit showing the drum coupling.

[0080] Figure 56 is an illustration of a drum unit showing a drum coupling. 20

[0081] Figure 57 is a perspective view of the drum unit showing the drum coupling.

[0082] Figure 58 is a top view of the drum coupling.

[0083] Figure 59 is a perspective view illustrating parts of the drive transmission unit. 25

[0084] Figure 60 is a perspective view of the drive transmission unit and the drum unit.

[0085] Figure 61 is a perspective view of the drive transmission unit and the 2026249127   12 Oct 2026 drum unit.

[0086] Figure 62 is a perspective view of the drive transmission unit and the drum unit.

[0087] Figure 63 is a perspective view of the drive transmission unit and the 5 drum unit.

[0088] Figure 64 is a perspective view of the drive transmission unit and the drum unit.

[0089] Figure 65 is a perspective view of the drive transmission unit and the drum unit. 10

[0090] Figure 66 is a perspective view of the drive transmission unit and the drum unit.

[0091] Figure 67 is a perspective view of the drive transmission unit and the drum unit.

[0092] Figure 68 is a perspective view of the drive transmission unit and the 15 drum unit.

[0093] Figure 69 is a perspective view of the drive transmission unit and the drum unit.

[0094] Figure 70 is a perspective view of the drive transmission unit and the drum unit. 20

[0095] Figure 71 is a perspective view of the drive transmission unit and the drum unit.

[0096] Figure 72 is a perspective view of the drive transmission unit and the drum unit.

[0097] Figure 73 is a perspective view illustrating a modified example of the 25 drum coupling.

[0098] Figure 74 is a perspective view and a front view illustrating a modified example of the drum coupling. 2026249127   12 Oct 2026

[0099] Figure 75 is a perspective view of the drum unit.

[0100] Figure 76 is a developed view illustrating the engagement of the drum coupling.

[0101] Figure 77 is a perspective view of the drum unit and a front view of the 5 coupling.

[0102] Figure 78 is a perspective view of the drum unit and the drive transmission unit.

[0103] Figure 79 is a side view, a perspective view, and a front view of the coupling. 10

[0104] Figure 80 is a side view of the coupling.

[0105] Figure 81 is a side view and a perspective view of the coupling.

[0106] Figure 82 is a schematic sectional view of the image forming apparatus.

[0107] Figure 83 is a schematic sectional view of the process cartridge.

[0108] Figure 84 is a schematic perspective view of the process cartridge. 15

[0109] Figure 85 is a schematic perspective view of the process cartridge.

[0110] Figure 86 is a schematic sectional view of the process cartridge taken along a rotational axis of the photosensitive drum.

[0111] Figure 87 is an exploded perspective view of a drive transmission unit 811. 20

[0112] Figure 88 is a sectional view taken along the rotation axis of the drive transmission unit 811 mounted to the main assembly of the image forming apparatus.

[0113] Figure 89 is a schematic perspective view of another form of the drum coupling 770. 25

[0114] Figure 90 is a schematic perspective view illustrating mounting of the cartridge 701 to the image forming apparatus main assembly 800.

[0115] Figure 91 is a schematic sectional view illustrating the mounting 2026249127   12 Oct 2026 operation of the cartridge 701 to the image forming apparatus main assembly 800.

[0116] Figure 92 is a schematic sectional view illustrating the mounting operation of the drum coupling 770 to the main assembly drive transmission unit 811. 5

[0117] Figure 93 is a schematic sectional view illustrating the mounting operation of the drum coupling 770 to the main assembly drive transmission unit 811.

[0118] Figure 94 is a perspective view illustrating another form of the process cartridge. 10

[0119] Figure 95 is a sectional view of the drum unit.

[0120] Figure 96 is a front view of the coupling.

[0121] In Figure 97, part (a) is a perspective view of the coupling, and part (b) is a front view.

[0122] Figure 98 is a front view of the coupling. 15

[0123] Figure 99 is a perspective view illustrating an engaged state of the coupling and the braking engagement member.

[0124] Figure 100 is a front view of the coupling.

[0125] Figure 101 is a front view of the coupling.

[0126] Figure 102 is a front view, a perspective view, and a side view of the 20 coupling.

[0127] Figure 103 is a perspective view illustrating an engaged state of the coupling and the braking engagement member.

[0128] Figure 104 is a perspective view and a side view of the drum unit.

[0129] Figure 105 is a perspective view of the drum unit and a front view of 25 the coupling.

[0130] Figure 106 is a sectional view of the drum unit.

[0131] Figure 107 is a perspective view of the drum unit. 2026249127   12 Oct 2026

[0132] Figure 108 is a sectional view of the coupling.

[0133] Figure 109 is a perspective view of the drum unit.

[0134] Figure 110 is a sectional view of the drum unit and the drive transmission unit. 5

[0135] Figure 111 is a perspective view of the drum coupling 1100.

[0136] Figure 112 is an enlarged perspective view of the drum coupling 1100.

[0137] Figure 113 is a front view of the drum coupling 1100.

[0138] Figure 114 is a perspective view illustrating a modified example of the drum coupling 1100. 10

[0139] Figure 115 is exploded perspective views of the drum coupling 1206.

[0140] Figure 116 is a sectional view of the drum coupling 1206.

[0141] Figure 117 is perspective views illustrating the operation of the drum coupling 1206.

[0142] Figure 118 is perspective views and sectional views illustrating the 15 operation of the drum coupling 1206.

[0143] Figure 119 is perspective views and sectional views illustrating the operation of the drum coupling 1206.

[0144] Figure 120 is perspective views and sectional views illustrating the operation of the drum coupling 1206. 20

[0145] Figure 121 is perspective views and exploded perspective views of the drive transmission unit 203.

[0146] Figure 122 is a cross-sectional view and a side view of the drive transmission unit 203.

[0147] Figure 123 is exploded perspective views of the drum coupling 1342. 25

[0148] Figure 124 is front views and perspective views of the drum coupling 1342.

[0149] Figure 125 is perspective views illustrating an engagement operation 2026249127   12 Oct 2026 between the drum coupling and the drive transmission unit 203.

[0150] Figure 126 is sectional views illustrating an engagement operation between the drum coupling 1342 and the drive transmission unit 203.

[0151] Figure 127 is cross-sectional views illustrating an engagement 5 operation between the drum coupling 1342 and the drive transmission unit 203.

[0152] Figure 128 is perspective views illustrating an engagement operation between the drum coupling and the drive transmission unit 203.

[0153] Figure 129 is cross-sectional views illustrating an engagement operation between the drum coupling 1342 and the drive transmission unit 203. 10

[0154] Figure 130 is cross-sectional views illustrating an engagement operation between the drum coupling 1342 and the drive transmission unit 203.

[0155] Figure 131 is front views of the drum coupling 1342.

[0156] Figure 132 is a perspective view illustrating the internal structure of the drum coupling 1206. 15

[0157] Figure 133 is a perspective view and a front view of a second brake engaging member 208.

[0158] Figure 134 is exploded perspective views of the drum coupling 1545.

[0159] Figure 135 is a front view and a sectional view of the engaging member 1543 as viewed from the driving side. 20

[0160] Figure 136 is a perspective view, a front view, and a sectional view illustrating the engagement between the engaging member 1543 and the flange member 1544.

[0161] Figure 137 is front perspective views and an engagement illustration of the drum coupling 1545 and the drive transmission unit 203. 25

[0162] Figure 138 is cross-sectional views of the drum coupling 1545 and the drive transmission unit before and after engagement, respectively.

[0163] Figure 139 is a perspective view illustrating the drive transmission of 2026249127   12 Oct 2026 the second brake engaging member 208 and a drum drive coupling 180.

[0164] Figure 140 is a side view and a cross-sectional view of the second brake engaging member 208 and the drive transmission unit 203.

[0165] Figure 141 is illustration showing a deformed state of the second brake 5 engaging member 208.

[0166] Figure 142 is a sectional perspective view of the drum coupling 1545 and the drive transmission unit 203.

[0167] Figure 143 is sectional views of the drum coupling 1545 and the drive transmission unit 203. 10

[0168] Figure 144 is a perspective view of another form of drum coupling 1546.

[0169] Figure 145 is front views of the drum coupling.

[0170] Figure 146 is front views of the drum coupling.

[0171] Part (a) of Figure 147 and part (b) of Figure 147 are perspective views 15 of the drum coupling. Part (c) of Figure 147 is illustrations showing the engagement states of the drive transmission unit and the engaging member.

[0172] Figure 148 is perspective views of the drum coupling.

[0173] Part (a) of Figure 149 is a side view of the drum coupling. Part (b) of Figure 149 is a perspective view of the drum coupling. 20

[0174] Part (a) of Figure 150 is a front view of the drum coupling. Part (b) of Figure 150 is a perspective view of the drum coupling. [Description of the Embodiments] << Embodiment 1 >>

[0175] Hereinafter, a mode for carrying out the present invention will be 25 described in detail exemplarily with reference to the drawings and examples. However, the functions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope 2026249127   12 Oct 2026 of the present invention to those, unless otherwise specified.

[0176] Hereinafter, the Embodiment 1 will be described with reference to the drawings.

[0177] In the following embodiment, as the image forming apparatus, an 5 image forming apparatus which four process cartridges can be mounted to and dismounted from is illustrated.

[0178] The number of process cartridges mounted on the image forming apparatus is not limited to this example. It is selected appropriately as needed.

[0179] Further, in the embodiment described below, a laser beam printer is 10 exemplified as one aspect of the image forming apparatus. [Outline structure of image forming apparatus]

[0180] Figure 2 is a schematic sectional view of the image forming apparatus M. Further, Figure 3 is a sectional view of the process cartridge 100. 15

[0181] The image forming apparatus M is a four-color full-color laser printer using an electrophotographic process, and forms a color image on the recording material S. The image forming apparatus M is a process cartridge type, and a process cartridge is dismountably mounted to the image forming apparatus main assembly (apparatus main assembly, electrophotographic image forming 20 apparatus main assembly) 170 to form a color image on the recording material S.

[0182] Here, regarding the image forming apparatus M, the side where the front door 11 is provided is the front surface (front surface), and the surface opposite to the front surface is the back surface (rear surface). Further, the right side of the image forming apparatus M as viewed from the front is referred to as a 25 driving side, and the left side is referred to as a non-driving side.

[0183] Further, as the image forming apparatus M is viewed from the front side, the upper side is the upper surface and the lower side is the lower surface. 2026249127   12 Oct 2026 Figure 2 is a sectional view of the image forming apparatus M as viewed from the non-driving side; the front side of the sheet of the drawing is the non-driving side of the image forming apparatus M; the right side of the sheet of the drawing is the front side; and the rear side of the sheet of the drawing is the driving side of the 5 image forming apparatus.

[0184] The driving side of the process cartridge 100 is the side on which the drum coupling (photosensitive member coupling) which will be described hereinafter is disposed in the axial direction of the photosensitive drum. Further, the driving side of the process cartridge 100 is also the side on which the 10 development coupling described hereinafter is arranged in the axial direction of the developing roller (developing member).

[0185] The axial direction of the photosensitive drum is a direction parallel to the rotation axis of the photosensitive drum, which will be described hereinafter. Similarly, the axial direction of the developing roller is a direction parallel to the 15 rotation axis of the developing roller, which will be described hereinafter. In this embodiment, the axis of the photosensitive drum and the axis of the developing roller are substantially parallel, and therefore, the axial direction of the photosensitive drum and the axial direction of the developing roller are considered to be substantially the same. 20

[0186] The image forming apparatus main assembly 170 has four process cartridges 100 (100Y, 100M, 100C, 100K), namely a first process cartridge 100Y, a second process cartridge 100M, a third process cartridge 100C, and a fourth process cartridge 100K, which are arranged almost horizontally.

[0187] Each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 25   100K) has the same electrophotographic process mechanism, and the colors of the developer (hereinafter referred to as toner) are different. Rotational driving force is transmitted to the first to fourth process cartridges 100 (100Y, 100M, 2026249127   12 Oct 2026 100C, 100K) from a drive output portion (details will be described hereinafter) of the image forming apparatus main assembly 170.

[0188] Further, bias voltages (charging bias, development bias, and so on) are supplied from the image forming apparatus main assembly 170 to each of the first 5 to fourth process cartridges 100 (100Y, 100M, 100C, 100K) (not shown).

[0189] As shown in Figure 3, each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) of this embodiment includes a photosensitive drum 104 and a drum holding unit 108 which is provided with charging means functioning as a process means acting on the photosensitive drum 104. Further, 10 each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) includes a developing unit 109 provided with a developing means for developing an electrostatic latent image on the photosensitive drum 104.

[0190] The drum holding unit 108 and the developing unit 109 are coupled to each other. A more specific structure of the process cartridge 100 will be 15 described hereinafter.

[0191] The first process cartridge 100Y contains yellow (Y) toner in a development frame 125, and forms a yellow-color toner image on the surface of the photosensitive drum 104.

[0192] The second process cartridge 100M contains magenta (M) toner in a 20 development frame 125, and forms a magenta-color toner image on the surface of the photosensitive drum 104.

[0193] The third process cartridge 100C contains cyan (C) toner in a development frame 125, and forms a cyan-color toner image on the surface of the photosensitive drum 104. 25

[0194] The fourth process cartridge 100K contains black (K) toner in a development frame 125, and forms a black toner image on the surface of the photosensitive drum 104. A laser scanner unit 14 as an exposure means is 2026249127   12 Oct 2026 provided above the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K). The laser scanner unit 14 outputs a laser beam U corresponding to the image information. The laser beam U passes through the exposure window 110 of the process cartridge 100 and scans so that the surface of the photosensitive 5 drum 104 is exposed to the laser beam U.

[0195] Below the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K), an intermediary transfer unit 12 as a transfer member is provided. The intermediary transfer unit 12 includes a drive roller 12e, a turn roller 12c, and a tension roller 12b, and a flexible transfer belt 12a is extended around these rollers. 10

[0196] The lower surface of the photosensitive drum 104 of each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) is in contact with the upper surface of the transfer belt 12a. The contact portion is the primary transfer portion. Inside the transfer belt 12a, a primary transfer roller 12d is provided so as to oppose the photosensitive drum 104. 15

[0197] The secondary transfer roller 6 is brought into contact with the turn roller 12c by way of the transfer belt 12a. The contact portion between the transfer belt 12a and the secondary transfer roller 6 is the secondary transfer portion.

[0198] A feeding unit 4 is provided below the intermediary transfer unit 12. 20 The feeding unit 4 includes a sheet feed tray 4a on which the recording material S is loaded and accommodated, and a sheet feeding roller 4b.

[0199] A fixing device 7 and a paper discharge ion device 8 are provided on the upper left side of the image forming apparatus main assembly 170 in Figure 2. The upper surface of the image forming apparatus main assembly 170 functions 25 as a paper discharge tray 13.

[0200] The toner image is fixed on the recording material S by a fixing means provided in the fixing device 7, and the recording material is discharged to the 2026249127   12 Oct 2026 paper discharge tray 13. [Image forming operation]

[0201] The operation for forming a full-color image is as follows. 5

[0202] The photosensitive drum 104 of each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) is rotationally driven at a predetermined speed (in the direction of arrow A in Figure 3).

[0203] The transfer belt 12a is also rotationally driven in the forward direction (direction of arrow C in Figure 2) codirectionally with the rotation of the 10 photosensitive drum at a speed corresponding to the speed of the photosensitive drum 104.

[0204] The laser scanner unit 14 is also driven. In synchronization with the drive of the laser scanner unit 14, the charging roller 105 uniformly charges the surface of the photosensitive drum 104 to a predetermined polarity and potential 15 in each process cartridge. The laser scanner unit 14 scans and exposes the surface of each photosensitive drum 104 with laser beam U in accordance with the image signals of each color.

[0205] By this, an electrostatic latent image corresponding to the image signal of the corresponding color is formed on the surface of each photosensitive drum 20   104. The formed electrostatic latent image is developed by a developing roller 106 which is rotationally driven at a predetermined speed. More specifically, the developing roller 106 is in contact with the photosensitive drum 104, and the toner moves from the developing roller 106 to the latent image of the photosensitive drum 104, so that the latent image is developed into a toner image. 25 In this embodiment, the contact developing method is employed, and the developing roller 106 and the photosensitive drum 104 are in contact with each other. However, there a non-contact development method may be employed in 2026249127   12 Oct 2026 which toner jumps from the developing roller 106 to the photosensitive drum 104 through a small gap between the developing roller 106 and the photosensitive drum 104.

[0206] Through the electrophotographic image forming process operation as 5 described above, a yellow toner image corresponding to the yellow component of the full-color image is formed on the photosensitive drum 104 of the first process cartridge 100Y. Then, the toner image is primary-transferred onto the transfer belt 12a. A part of the photosensitive drum 104 is exposed to the outside of the cartridge and is in contact with the transfer belt 12a. At this contact portion, the 10 toner image on the surface of the photosensitive drum 104 transferred onto the transfer belt 12a.

[0207] Similarly, a magenta color toner image corresponding to the magenta component of the full color image is formed on the photosensitive drum 104 of the second process cartridge 100M. Then, the toner image is superimposedly 15 transferred onto the yellow toner image already transferred on the transfer belt 12a.

[0208] Similarly, a cyan toner image corresponding to the cyan component of the full-color image is formed on the photosensitive drum 104 of the third process cartridge 100C. Then, the toner image is superimposedly primary-transferred 20 onto the yellow-colored and magenta-colored toner images already transferred on the transfer belt 12a.

[0209] Similarly, a black toner image corresponding to the black component of the full-color image is formed on the photosensitive drum 104 of the fourth process cartridge 100K. Then, the toner image is superimposedly primary-25 transferred onto the yellow, magenta, and cyan toner images already transferred on the transfer belt 12a.

[0210] In this manner, a four-color full-color unfixed toner image of yellow, 2026249127   12 Oct 2026 magenta, cyan, and black is formed on the transfer belt 12a.

[0211] On the other hand, the recording materials S are separated and fed one by one at a predetermined controlled timing. The recording material S is introduced then into the secondary transfer portion, which is the contact portion 5 between the secondary transfer roller 6 and the transfer belt 12a, at a predetermined control timing.

[0212] By this, in the process of feeding the recording material S to the secondary transfer unit, the four-color superimposed toner images on the transfer belt 12a are sequentially and collectively transferred onto the surface of the 10 recording material S.

[0213] In more detail, the structure of the image forming apparatus main assembly will be described below. [Outline of process cartridge mounting / dismounting structure] 15

[0214] Referring to Figures 42 and 4 to 7, the tray 171 which supports the process cartridge will be described in more detail. Figure 4 is a sectional view of the image forming apparatus M in which the tray 171 is located inside the image forming apparatus main assembly 170 with the front door 11 open. Figure 5 is a sectional view of the image forming apparatus M in a state in which 20 the tray 171 is located outside the image forming apparatus main assembly 170 with the front door 11 open and the process cartridges 100 accommodated in the tray. Figure 6 is a sectional view of the image forming apparatus M in a state in which the tray 171 is located outside the image forming apparatus main assembly 170 with the front door 11 open and the process cartridge 100 having been 25 removed from the tray. Part (a) of Figure 7 is a partial detailed view of the tray 171 as viewed from the driving side in the state shown in Figure 4. Part (b) of Figure 7 is a partial detailed view of the tray 171 as viewed from the non-driving 2026249127   12 Oct 2026 side in the state of Figure 4.

[0215] As shown in Figures 4 and 5, the tray 171 can be moved in the arrow X1 direction (pushing direction) and the arrow X2 direction (pulling direction) relative to the image forming apparatus main assembly 170. That is, the tray 5    171 is provided so as to be retractable from and insert able into the image forming apparatus main assembly 170, and the tray 171 is structured to be movable in a substantially horizontal direction in a state where the image forming apparatus main assembly 170 is installed on a horizontal floor. Here, the state in which the tray 171 is located outside the image forming apparatus main assembly 10    170 (the state shown in Figure 5) is referred to as an outside position. Further, a state in which the tray is placed inside the image forming apparatus main assembly 170 with the front door 11 open and the photosensitive drum 104 and the transfer belt 12a are separated from each other (state in Figure 4) is referred to as an inner position. 15

[0216] Further, the tray 171 has a mounting portion 171a in which the process cartridges 100 can be dismountably mounted as shown in Figure 6 in the outer position. Then, each process cartridge 100 mounted on the mounting portion 171a in the outer position of the tray 171 is supported by the tray 171 by the driving side cartridge cover member 116 and the immovable side cartridge cover 20 member 117 as shown in Figure 7. Then, the process cartridge moves inside the image forming apparatus main assembly 170 with the movement of the tray 171 in a state of being placed in the mounting portion 171a. At this time, in the movement, a gap is kept between the transfer belt 12a and the photosensitive drum 104. The tray 171 can carry the process cartridge 100 into the image 25 forming apparatus main assembly 170 without the photosensitive drum 104 contacting with the transfer belt 12a (details will be described hereinafter).

[0217] As described above, by using the tray 171, a plurality of process 2026249127   12 Oct 2026 cartridges 100 can be collectively moved to a position where image formation is possible inside the image forming apparatus main assembly 170, and is collectively moved to the outside of the image forming apparatus main assembly 170. 5 [Positioning of process cartridge relative to electrophotographic image forming apparatus main assembly]

[0218] Referring to Figure 7, the positioning of the process cartridge 100 relative to the image forming apparatus main assembly 170 will be described 10 more specifically.

[0219] As shown in Figure 7, the tray 171 is provided with positioning portions 171VR and 171VL for holding the cartridge 100. The positioning portion 171VR has straight portions 171VR1 and 171VR2, respectively. The center of the photosensitive drum is determined by the arc portions 116VR1 and 15   116VR2 of the cartridge cover member 116 shown in Figure 7 contacting with the straight portions 171VR1 and 171VR2.

[0220] Further, the tray 171 shown in Figure 7 is provided with a rotationdetermining projection 171KR. The attitude of the process cartridge 100 is determined relative to the apparatus main assembly by fitting it with the rotation 20 determining recess 116KR of the cartridge cover member 116 shown in Figure 7.

[0221] The positioning portion 171VL and the rotation determining projection 171KL are arranged at positions (non-driving side) so as to oppose each other across the intermediary transfer belt 12a in the longitudinal direction of the positioning portion 171VR and the process cartridge 100. That is, on the non- 25 driving side as well, the position of the process cartridge is determined by engagement of the arc portions 117VL1 and 117VL2 of the cartridge cover member 117 with the positioning portion 171VL and engagement of the rotation 2026249127   12 Oct 2026 determining recess 117KL with the rotation determining projection 171KL.

[0222] By doing so, the position of the process cartridge 100 relative to the tray 171 is correctly determined.

[0223] Then, as shown in Figure 5, the process cartridge 100 integrated with 5 the tray 171 is moved in the direction of the arrow X1 and inserted to the position shown in Figure 5.

[0224] Then, by closing the front door 11 in the direction of the arrow R, the process carriage 100 is pressed by a cartridge pressing mechanism (not shown) which will be described hereinafter, and is fixed to the image forming apparatus 10 main assembly 170 together with the tray 171. Further, the transfer belt 12a comes into contact with the photosensitive member 104 in interrelation with the operation of the cartridge pressing mechanism. In this state, an image formation is enabled (Figure 2).

[0225] In this embodiment, the positioning portion 171VR and the positioning 15 portion 171V also serve as reinforcements for maintaining the rigidity in the pullout operation of the tray 171, and for this reason, the use is made with metal sheet, but the present invention is not limited to this. [Cartridge pressing mechanism] 20

[0226] Next, referring to Figure 8, the details of the cartridge pressing mechanism will be described.

[0227] Part (a) of Figure 8 shows only the process cartridge 100, the tray 171, the cartridge pressing mechanisms 190 and 191 and the intermediary transfer unit 12 in the state of Figure 4. Part (b) of Figure 8 shows only the process cartridge 25   100, the tray 171, the cartridge pressing mechanisms and 191 and the intermediary transfer unit 12 in the state of Figure 2.

[0228] The process cartridge 100 receives a driving force during image 2026249127   12 Oct 2026 formation, and further receives a reaction force from the primary transfer roller 12d (Figure 2) in the direction of arrow Z1. Therefore, it is necessary to press the process cartridge in the Z2 direction in order to maintain a stable attitude without the process cartridge spacing from the positioning portions 171VR and 5   171VL during the image forming operation.

[0229] In order to achieve these, in this embodiment, the image forming apparatus main assembly 170 is provided with cartridge pressing mechanisms (190, 191).

[0230] As for the cartridge pressing mechanism (190, 191), the storing 10 element pressing unit 190 works for the non-driving side, and the cartridge pressing unit 191 works for the driving side. This will be described in more detail below.

[0231] By closing the front door 11 shown in Figure 4, the storing element pressing unit 190 and the cartridge pressing unit 191 shown in Figure 8 lowers in 15 the direction of arrow Z2.

[0232] The storing element pressing unit 190 is provided with a main assembly side electric contact (not shown) which mainly contacts with the electric contact of the storing element (not shown) provided in the process cartridge 100. By interlocking with the front door 11 by a link mechanism (not 20 shown), the storing element 140 and the electric contact on the main assembly side can be brought into and out of contact with each other.

[0233] That is, the contacts are brought into contact with each other by closing the front door 11, and the contacts are separated by opening the front door 11.

[0234] By such a structure, when the process cartridge 100 moves inside the 25 image forming apparatus main assembly together with the tray 171, the electric contacts are not rubbed and the contacts are retracted from the insertion / removal locus of the process cartridge 100, whereby insertion and removal operations of 2026249127   12 Oct 2026 the tray 171 are not hindered.

[0235] The storing element pressing unit 190 also functions to press the process cartridge against the positioning portion 171VR described above.

[0236] Further, similarly to the storing element pressing unit 190, the cartridge 5 pressing unit 121 also lowers in the direction of arrow Z2 in interrelation with the operation of closing the front door 11 and functions to press the process cartridge 100 against the above-mentioned positioning portion 171VL.

[0237] Further, although the details will be described hereinafter, the cartridge pressing mechanism (190, 191) also functions to press down the force applying 10 members 152L and 152R of the process cartridge 100 as will be described hereinafter. [Drive transmission mechanism]

[0238] Next, referring to Figures 9 and 10 (for better illustration, the tray 171 15 is omitted), the drive transmission mechanism of the main assembly in this embodiment will be described.

[0239] Part (a) of Figure 9 is a perspective view in which the process cartridge 100 and the tray 171 are omitted in the state of Figure 4 or Figure 5. Figure9B is a perspective view in which the process cartridge 100, the front door 11 and the 20 tray 171 are omitted.

[0240] Figure 10 is a side view of the process cartridge 100 as viewed from the driving side.

[0241] As shown in Figure 10, the process cartridge in this embodiment includes a development coupling portion 32a and a drum coupling 25 (photosensitive member coupling) 143.

[0242] The structure is such that by closing the front door 11 (state of part (b) of Figure 9, the main assembly side drum drive coupling and the main assembly 2026249127   12 Oct 2026 side development drive coupling 185 which drive and transmit the driving forces to the process cartridge 100 are projected in the arrow Y1 direction by a link mechanism (not shown).

[0243] Further, by opening the front door 11 (state of part (a) of Figure 9, the 5 drum drive coupling 180 and the development drive coupling 185 are retracted in the direction of arrow Y2.

[0244] By retracting each coupling from the insertion / removal locus of the process cartridge (X1 direction, X2 direction), the insertion / removal of the tray 171 is not hindered. 10

[0245] By closing the front door 11 and starting the driving of the image forming apparatus main assembly, the drum drive coupling 180 described above engages with the drum coupling (coupling member, cartridge side coupling) 143. Along with this, the development drive coupling 185 on the main assembly side engages with the development coupling portion 32a. As a result, the drive is 15 transmitted to the process cartridge 100. The drive transmission to the process cartridge 100 is not limited to the structure described above, and a mechanism which inputs the drive only to the drum coupling and transmits the drive to the developing roller may be provided. 20 [Intermediary transfer unit structure]

[0246] Next, referring to Figure 9, the intermediary transfer unit 12 of the image forming apparatus main assembly in this embodiment will be described.

[0247] In this embodiment, the structure is such that the intermediary transfer unit 12 is raised in the direction of arrow R2 by a link mechanism (not shown) by 25 closing the front door 11, and moves to the position for the image forming operation (photosensitive drum 104 and intermediary transfer belt 12a are in contact with each other). 2026249127   12 Oct 2026

[0248] Further, by opening the front door 11, the intermediary transfer unit 12 lowers in the direction of arrow R1, and the photosensitive drum 2 and the intermediary transfer belt 12a are separated from each other.

[0249] That is, in a state in which the process cartridge 100 is set in the tray 5   171, the photosensitive drum 104 and the intermediary transfer belt 12a come into and out of contact with each other depending on the opening / closing operation of the front door 11.

[0250] The structure is such that in the contact / separation operation, the intermediary transfer unit rises and falls while drawing a rotation locus about the 10 center point PV1 shown in Figure 4.

[0251] The intermediary transfer belt 12a is driven by receiving a force from a gear (not shown) provided coaxially with the PVI. Therefore, by setting the above-mentioned position PV1 as the rotation center, the intermediary transfer unit 12 can be raised and lowered without moving the gear center. By doing so, 15 it is not necessary to move the center of the gear, and the position of the gear can be maintained with high accuracy.

[0252] With the above-described structure, in the state that the process cartridge 100 is set in the tray 171, when the tray 11 is inserted or removed, the photosensitive drum 104 and the intermediary transfer belt 12a do not rub relative 20 to each of, and therefore, damage of the photosensitive drum 104 and deterioration of the image by charge memory are prevented. [Development separation control unit]

[0253] Next, referring to Figures 8, 11 and 12, the separation mechanism of 25 the image forming apparatus main assembly in this embodiment will be described.

[0254] Figure 11 is a sectional view of the image forming apparatus M taken along the driving side end of the process cartridge 100. Figure 12 is a 2026249127   12 Oct 2026 perspective view of the development separation control unit as viewed obliquely from above.

[0255] In this embodiment, the development separation control unit 195 controls the separation contact operation of the developing unit 109 relative to the 5 photosensitive drum 104 by engaging with a portion of the developing unit 109. The development separation control unit 195 is disposed in a lower portion the image forming apparatus main assembly 170 as shown in Figure 8.

[0256] Specifically, the development separation control unit 195 is placed below the development input coupling portion 32a and the drum coupling 143 in 10 the vertical direction (downward in the arrow Z2 direction).

[0257] Further, the development separation control unit 195 is placed in the longitudinal direction (Y1, Y2 direction) of the photosensitive drum 104 of the intermediary transfer belt 12. That is, the development separation control unit 195 includes a development separation control unit 195R on the driving side and 15 a development separation control unit 195L on the non-driving side.

[0258] By disposing the development separation control unit 195 in the dead space of the image forming apparatus main assembly 170 as described above, the main assembly can be downsized.

[0259] The development separation control unit 195R has four separation 20 control members 196R corresponding to the process cartridges 100 (100Y, 100M, 100C, 100K), respectively. The four separation control members have substantially the same shape. The development separation control unit 195R is always fixed to the image forming apparatus main assembly. However, the separation control member 196R is structured to be movable in the W41 and W42 25 directions by a control mechanism (not shown). The detailed structure will be described hereinafter.

[0260] The development separation control unit 195L has four separation 2026249127   12 Oct 2026 control members 196L corresponding to the process cartridge 100 (100Y, 100M, 100C, 100K). The four separation control members have substantially the same shape. The development separation control unit 195L is always fixed to the image forming apparatus main assembly. However, the separation control 5 member 196L is structured to be movable in the W41 and W42 directions by a control mechanism (not shown). The detailed structure will be described hereinafter.

[0261] Further, in order for the development separation control unit 195 to engage with a portion of the developing unit 109 and control the separation 10 contact operation of the developing unit 109, a portion of the development control unit 196 and a portion of the developing unit are required to overlap in the vertical direction (Z1, Z2 direction).

[0262] Therefore, for the overlapping in the vertical direction (Z1 and Z2 directions) as described above after the developing unit 109 of the process 15 cartridge 100 is inserted in the X1 direction, a part of the developing unit (in the case of this embodiment, the force applying member 152) is required to project. Details will be described hereinafter.

[0263] In the case that the development separation control unit 195 itself is raised in the same manner as in the case of the intermediary transfer unit 12 for 20 the engagement, there are problems such as an increase in the operating force of the interlocked front door 11 and complication of the drive train.

[0264] In this embodiment, a method is employed in which the development separation control unit 195 is fixed to the image forming apparatus main assembly 170, and a part of the developing unit 109 (force applying member 152) 25 is projected downward (Z2) in the image forming apparatus main assembly 170, and one of the reasons for this arrangement is to address this problem. Further, the mechanism for projecting the force applying member 152 utilized the 2026249127   12 Oct 2026 mechanisms of the storing element pressing unit 190 and the cartridge pressing unit described above, and therefore, there is no above-described problem and an increase in the cost of the device main assembly can be suppressed.

[0265] The entire unit of the development separation control unit 195 is fixed 5 to the image forming apparatus main assembly 170. However, as will be described hereinafter, a part of the developing unit is movable in order to engage with the force applying member 152 to cause an operation so that the developing unit 109 is in a separated state and a contacted state relative to the photosensitive drum 104. Details will be described hereinafter. 10 [Overall structure of process cartridge]

[0266] Referring to Figures 3, 13 and 14, the structure of the process cartridge will be described.

[0267] Figure 13 is an assembly perspective view of the process cartridge 100 15 as viewed from the driving side, which is one side in the axial direction of the photosensitive drum 104. Figure 14 is a perspective view of the process cartridge 100 as viewed from the driving side.

[0268] In this embodiment, the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) have the same electrophotographic process mechanism, but 20 the color of the contained toner and the filling amount of the toner are different from each other.

[0269] The process cartridge 100 includes a photosensitive drum 104 (4Y, 4M, 4C, 4K) and process means which act on the photosensitive drum 104. The 25 cartridge 100 includes a charging roller 105 as a process means, which is a charging means (charging member) for charging the photosensitive drum 104. Further, the cartridge 100 includes a developing roller 106 which is a developing 2026249127   12 Oct 2026 means (developing member) for developing the latent image formed on the photosensitive drum 104 as another process means.

[0270] In addition, as an example of the process means, there is a cleaning means (, for example, a cleaning blade or the like) for removing residual toner 5 remaining on the surface of the photosensitive drum 104 can be considered. However, the image forming apparatus of this embodiment employs a structure in which the cleaning means contacting the photosensitive drum 104 is not provided.

[0271] The process cartridge 100 is divided into a drum holding unit 108 (108Y, 108M, 108C, 108K) and a developing unit 109 (109Y, 109M, 109C, 10   109K). [Drum holding unit structure]

[0272] As shown in Figures 3 and 13, the drum holding unit 108 comprises a photosensitive drum 104, a charging roller 105, and a drum frame 115 which is a 15 first frame, and so on. The photosensitive drum 104 unified together with the coupling 143 and the drum flange 142 to provide the drum unit 103 (see part (a) of Figure 1, the details will be described hereinafter).

[0273] The drum unit 103 is rotatably supported by a driving side cartridge cover member 116 and a non-driving side cartridge cover member 117 provided 20 at the opposite ends in the longitudinal direction of the process cartridge 100. The driving side cartridge cover member 116 and the non-driving side cartridge cover member 117 will be described hereinafter.

[0274] Further, as shown in Figures 13 and 14, a drum coupling 143 for transmitting a driving force to the photosensitive drum 104 is provided in the 25 neighborhood of one end in the longitudinal direction of the photosensitive drum 104. As described above, the coupling 143 engages with the main assembly side drum drive coupling 180 (see Figure 9) as the drum drive output unit of the 2026249127   12 Oct 2026 image forming apparatus main assembly 170. The driving force of the driving motor (not shown) of the image forming apparatus main assembly 170 is transmitted to the photosensitive drum 104 to rotate it in the direction of arrow A. Further, the photosensitive drum 104 is provided with a drum flange 142 in the 5 neighborhood of the other end (second end portion) in the longitudinal direction.

[0275] The shaft portion 143j (see Figure 1) of the coupling 143 is supported by the driving side cartridge cover 116, and the drum flange 142 is supported by the shaft fixed to the non-driving side cartridge cover 117. By this, the drum unit 103 is rotatably supported in the cartridge. That is, the ends of the 10 photosensitive drum 104 are rotatably supported by the ends of the casing of the cartridge (that is, the cartridge covers 116 and 117) by way of the coupling 143 and the drum flange 142.

[0276] The charging roller 105 is supported by the drum frame 115 in contact with the photosensitive drum 104 so that it can be rotationally driven by the 15 photosensitive drum 104.

[0277] Of the opposite sides of the drum unit 103 in the longitudinal direction (axial direction), the side on which the coupling 143 is provided is the driving side, and the side on which the drum flange 142 is placed is the non-driving side. That is, of the opposite ends of the photosensitive drum 104 in the axial direction, 20 the coupling 143 is fixed in the neighborhood of the end on the driving side, and the drum flange 142 is fixed in the neighborhood of the end on the opposite side to the driving side. Of opposite ends of the photosensitive drum 104, one may be referred to as a first end and the other may be referred to as a second end. Figure 80 shows the end portion 104a on the drum driving side and the end 25 portion 104b on the non-driving side of the photosensitive drum.

[0278] Similarly to the drum unit 103, of the opposite sides of the cartridge 100, the side on which the coupling 143 is placed is referred to as the driving side, 2026249127   12 Oct 2026 and the side opposite to the driving side is referred to as the non-driving side. For example, Figures 10 and 19 are illustrations showing the driving side of the cartridge. Further, Figure 16 is an illustration showing the non-driving side of the cartridge. 5

[0279] As shown in Figures 13 and 14, the driving side cartridge cover 116 is a component provided at the driving side end of the casing of the cartridge 100, and the non-driving side cartridge cover is a component provided at the nondriving side end of the casing. The drum coupling 143 supported by the driving side cartridge cover 116 can be considered to be located in the neighborhood of 10 the non-driving side end of the casing of the cartridge 100. Of the opposite ends of the cartridge 100, one may be referred to as a first end and the other may be referred to as a second end. [Development unit structure] 15

[0280] As shown in Figures 3 and 13, the developing unit 109 includes a developing roller 106, a toner feeding roller (toner supply roller) 107, a developing blade 130, a developing unit frame 125, and the like. The developing unit frame 125 comprises a lower frame 125a and a lid member 125b. The lower frame 125a and the lid member 125b are connected by ultrasonic 20 welding or the like.

[0281] The development frame 125, which is the second frame (second casing), includes a toner accommodating portion 129 for accommodating toner to be supplied to the developing roller 106. Further, the development frame 125 rotatably supports the developing roller 106 and the toner feeding roller 107 by 25 way of the driving side bearing 126 and the non-driving side bearing 127, which will be described hereinafter, and holds the developing blade 130 for regulating a layer thickness of the toner on the peripheral surface of the developing roller 106. 2026249127   12 Oct 2026

[0282] The developing blade 130 is formed by mounting an elastic member 130b, which is a sheet-like metal having a thickness of about 0.1 mm, on a support member 130a, which is a metal material having an L-shaped crosssection, by welding or the like. The developing blade 130 is mounted to the 5 development frame 125 with fixing screws 130c at two locations, one in the neighborhood of one end and the other in the neighborhood of the other end in the longitudinal direction. The developing roller 106 comprises a core metal 106c and a rubber portion 106d.

[0283] The developing roller 106 is rotatably supported by a driving side 10 bearing 126 and a non-driving side bearing 127 mounted to the opposite ends in the longitudinal direction of the development frame 125, respectively. The development frame 125, the driving side bearing 126, and the non-driving side bearing 127 are a part of the frame (casing) of the cartridge. In a broad sense, the bearings 126 and 127 may be regarded as a part of the development frame 15   125, and the bearings 126 and 127 and the development frame 125 may be collectively referred to as a development frame.

[0284] The toner feeding roller 107 conveys and supplies the toner contained in the toner accommodating portion 129 toward the developing roller 106 to develop the latent image on the photosensitive drum 104. The toner feeding 20 roller 107 is in contact with the developing roller 106.

[0285] Further, as shown in Figures 13 and 14, a development input coupling portion (development coupling) 32a for transmitting a driving force to the developing unit 109 is provided on one side of the developing unit 109 in the longitudinal direction. The development input coupling portion 32a engages 25 with the development drive coupling 185 (see Figure 9) on the main assembly side as the development drive output portion of the image forming apparatus main assembly 170, and the driving force of the drive motor (not shown) of the 2026249127   12 Oct 2026 image forming apparatus main assembly 170 is input to the developing unit 109.

[0286] The driving force inputted to the developing unit 109 is transmitted by a driving train (not shown) provided in the developing unit 109, so that the developing roller 106 can be rotated in the direction of arrow D in Figure 3. 5 Similarly, the driving force received by the development input coupling portion 32a also rotates the toner feeding roller 107 to supply toner to the developing roller 106.

[0287] On one side of the developing unit 109 in the longitudinal direction, a development cover member 128 which supports and covers a developing input 10 coupling portion 32a and a drive train (not shown) is provided. The outer diameter of the developing roller 106 is selected to be smaller than the outer diameter of the photosensitive drum 104. The outer diameter of the photosensitive drum 104 of this embodiment is selected to be in the range of ¢18 to ¢22 (mm), and the outer diameter of the developing roller 106 is selected to be 15 in the range of ¢8 to ¢14. By the selections of such outer diameters, efficient arrangement is possible. [Assembling of drum holding unit and developing unit]

[0288] Referring to Figure, the assembly of the drum holding unit 108 and the 20 developing unit 109 will be described The drum holding unit 108 and the developing unit 109 are connected by a driving side cartridge cover member 116 and a non-driving side cartridge cover member 117 provided at respective ends in the longitudinal direction of the process cartridge 100.

[0289] The driving side cartridge cover member 116 provided on one side 25 (driving side) of the process cartridge 100 in the longitudinal direction is provided with a developing unit support hole 116a for supporting the developing unit so as to be swingable (movable). Similarly, the non-driving side cartridge 2026249127   12 Oct 2026 cover member 117 provided on the other side (non-driving side) of the process cartridge 100 in the longitudinal direction is provided with a developing unit support hole 117a for swingably supporting the developing unit 109.

[0290] Further, the driving side cartridge cover member 116 and the non- 5 driving side cartridge cover member 117 are provided with drum support holes 116b and 117b for rotatably supporting the photosensitive drum 104. Here, on the driving side, the outer diameter portion of the cylindrical portion 128b of the development cover member 128 is fitted into the developing unit support hole 116a of the driving side cartridge cover member 116. On the non-driving side, 10 the outer diameter portion of the cylindrical portion (not shown) of the non driving side bearing 127 is fitted into the developing unit support hole 117a of the non-moving side cartridge cover member 117.

[0291] Further, the opposite ends of the photosensitive drum 104 in the longitudinal direction are fitted into the drum support holes 116b of the driving 15 side cartridge cover member 116 and the drum support holes 117b of the non driving side cartridge cover member 117, respectively. Then, the driving side cartridge cover member 116 and the non-driving side cartridge cover member are fixed to the drum frame 115 of the drum holding unit 108 with screws or adhesives (not shown). By this, the developing unit 109 is rotatably supported 20 by the driving side cartridge cover member 116 and the non-driving side cartridge cover member 117. The developing unit 109 can be moved (rotated) relative to the drum holding unit 108, and the developing roller 106 can be moved with respect to the photosensitive drum by this movement. At the time of image formation, the developing roller 106 can be placed at the position acting on the 25 photosensitive drum 104.

[0292] The drum frame 115 and the cover members 116 and 117 are a part of the cartridge frame (casing). More specifically, they are frames of the drum 2026249127   12 Oct 2026 holding unit 108. Further, since the cover members 116 and 117 are fixed to one end and the other end of the drum frame 115, respectively, the cover members 116 and 117 may be regarded as a part of the drum frame 115. Or, the cover members 116 and 117 and the drum frame 115 may be collectively referred 5 to as a drum frame.

[0293] Further, one of the frame (115, 116, 117) of the drum holding unit 108 and the frame (125, 126, 127) of the developing unit may be called a first frame (first casing), and the other may be called a second frame (second casing) or the like. Further, the frame (115, 116, 117) of the drum holding unit 108 and the 10 frame (125, 126, 127) of the developing unit may be collectively referred to as a frame of the cartridge (casing of the cartridge), without particular distinction between them.

[0294] Figure 14 shows a state in which the drum holding unit 108 and the developing unit 109 are assembled by the above-described steps to provide an 15 integral process cartridge 100.

[0295] The axis connecting the center of the developing unit support hole 116a of the driving side cartridge cover member 116 and the center of the developing unit support hole 117a of the non-moving side cartridge cover member 117 is referred to as a swing axis K. Here, the cylindrical portion 128b 20 of the development cover member 128 on the driving side is coaxial with the development input coupling 74. That is, the developing unit 109 has a structure in which a driving force is transmitted from the image forming apparatus main assembly 170 on the swing axis K. Further, the developing unit 109 is rotatably supported about the swing axis K. 25 [Structure of separation / contact mechanism]

[0296] The structure in which the photosensitive drum 104 of the process 2026249127   12 Oct 2026 cartridge 100 and the developing roller 106 of the developing unit 109 are separated from and contacted with each other in this embodiment will be described in detail. The process cartridge includes a separation contact mechanism 150R on the driving side and a separation contact mechanism 150L 5 on the non-driving side. Figure 15 shows an assembly perspective view of the driving side of the developing unit 109 including the separation contact mechanism 150R. Figure 16 shows an assembly perspective view of the developing unit including the separation contact mechanism 150L on the nondriving side. Regarding the separation contact mechanism, the details of the 10 separation contact mechanism 150R on the driving side will first be described, and then the separation contact mechanism 150L on the non-driving side will be described.

[0297] Since the separation contact mechanisms on the driving side and the non-driving side have almost the same functions, the same reference numerals are 15 used for both sides with the exception that R is added at the end for the driving side, and L is added for the non-driving side.

[0298] The separation contact mechanism 150R includes a separation holding member 151R which is a restriction member, a force applying member 152R which is a pressing member, and a tension spring 153. 20

[0299] The separation contact mechanism 150L includes a separation holding member 151L which is a restriction member, a force applying member 152L which is a pressing member, and a tension spring 153. [Detailed description of separation holding member R] 25

[0300] Referring to Figure 17, the separation holding member 151R will be described in detail.

[0301] Part (a) of Figure 17 is a front view of the separation holding member 2026249127   12 Oct 2026 151R per se of the process cartridge 100 as viewed from the driving side longitudinal direction. Parts (b) and (c) of Figure 17 are perspective views of the separation holding member 151R per se. Part (d) of Figure 17 is a view of the separation holding member 151R as viewed in the direction of arrow Z2 in 5 part (a) of Figure 17 (vertically upward in the image forming state). The separation holding member 151R includes an annular support receiving portion 151Ra, and includes a separation holding portion 151Rb projecting from the support receiving portion 151Ra in the radial direction of the support receiving portion 151Ra. The free end of the separation holding portion 151Rb has a 10 separation holding surface 151Rc having an arc shape having a center on the separation holding member swing axis H and inclined by an angle 01 with respect to the line HA parallel to the separation holding member swing axis H. The angle 01 is selected so as to satisfy the equation (1). 0° ^0 1^45° ... (1) 15

[0302] Further, the separation holding member 151R has a second restricted surface 151Rk adjacent to the separation holding surface 151Rc. Further, the separation holding member 151R is provided with a second pressed portion 151Rd projecting in the Z2 beyond the support receiving portion 151Ra, and an arc-shaped second pressed surface 151Re projecting from the second pressed 20 portion 151Rd in the direction of the separation holding member swing axis H of the support receiving portion 151Ra.

[0303] Furthermore, the separation holding member 151R includes a main body portion 151Rf connected to the support receiving portion 151Ra, and the main body portion 151Rf is provided with a spring hooked portion 151Rg 25 projecting in the direction of the separation holding member swing axis H of the support receiving portion 151Ra. Further, the main body portion 151Rf is provided with a rotation (on its own axis) prevention portion 151Rm projecting in 2026249127   12 Oct 2026 the Z2 direction, and the rotation prevention surface 151Rn is provided in a direction facing the second pressed surface 151Re. [Detailed description of force applying member R] 5

[0304] Referring to Figure 18,, the force applying member 152R will be described in detail.

[0305] Part (a) of Figure 18 is a front view of the force applying member 152R per se as viewed from the longitudinal direction of the process cartridge 100, and Figures 18B and 18C are perspective views of the force applying 10 member 152R per se.

[0306] The force applying member 152R is provided with an oblong-shaped oblong support receiving portion 152Ra. Here, the longitudinal direction of the oblong shape of the oblong support receiving portion 152Ra is indicated by an arrow LH, the upward direction is indicated by an arrow LH1, and the downward 15 direction is indicated by an arrow LH2. Further, the direction in which the oblong support receiving portion 152Ra is formed is indicated by as HB. The force applying member 152R has a projecting portion 152Rh formed on the downstream side in the arrow LH2 direction of the oblong support receiving portion 152Ra. The oblong support receiving portion 152Ra and the projecting 20 portion 152Rh are connected by a main body portion 152Rb. On the other hand, the force applying member 152R includes a pressed portion 152Re projecting in the arrow LH1 direction and substantially perpendicular to the arrow LH1 direction, and has an arc-shaped pressed surface 152Rf on the downstream side in the arrow LH1 direction and has a pushing restriction surface 152Rg on the 25 upstream side. Further, the force applying member 152R has a first at-accommodation restriction surface 152Rv extending from the main body portion 152Rb on the upstream side in the arrow LH2 direction, and a second at- 2026249127   12 Oct 2026 accommodation restricting surface 152Rw which is adjacent to the first at-accommodation restriction surface 152Rv and which is substantially parallel to the first pressing surface 152Rq.

[0307] The projecting portion 152Rh includes a first force receiving portion 5   152Rk and a second force receiving portion 152Rn which are arranged so as to be opposite from each other in a direction substantially perpendicular to the arrow LH2 direction at an end portion in the arrow LH2 direction. The first force receiving portion 152Rk and the second force receiving portion 152Rn have a first force receiving surface 152Rm and a second force receiving surface 152Rp 10 extending in the HB direction and having arc shapes, respectively. Further, the projecting portion 152Rh has a spring hooked portion 152Rs projecting in the HL direction and a locking portion 152Rt, and the locking portion 152Rt has a locking surface 152Ru facing in the same direction as the first force receiving surface 152Rp. 15

[0308] Further, the force applying member 152R is a part of the main body portion 152Rb, and is arranged on the upstream side of the second force receiving portion 152Rn in the arrow LH2 direction, and has a first pressing surface 152Rq facing in the same direction as the second force receiving surface 152Rp. Further, the force applying member 152R has a second pressing surface 152Rr 20 which is perpendicular to the first at-accommodation restriction surface 152Rv and which is opposite from the first pressing surface 152Rq.

[0309] When the process cartridge 100 is mounted on the image forming apparatus main assembly 170, the LH1 direction is substantially the same as the Z1 direction, and the LH2 direction is substantially the same as the Z2 direction. 25 Further, the HB direction is substantially the same as the longitudinal direction of the process cartridge 100. 2026249127   12 Oct 2026 [Assembling of separation / contact mechanism R]

[0310] Next, referring to Figures 10 and 15 to 19, the assembly of the separation contact mechanism will be described. Figure 19 is a perspective view of the process cartridge 100 after being assembled with the separation 5 holding member 151R, as viewed from the driving side.

[0311] As shown in Figure 15 described above, in the developing unit 109, the outer diameter portion of the cylindrical portion 128b of the development cover member 128 is fitted into the developing unit support hole portion 116a of the driving side cartridge cover member 116. By this, the developing unit 109 is 10 rotatably supported relative to the photosensitive drum 104 about the swing axis K. Further, the development cover member 128 includes a cylindrical first support portion 128c and a second support portion 128k projecting in the direction of the swing axis K.

[0312] The outer diameter of the first support portion 128c fits with the inner 15 diameter of the support receiving portion 151Ra of the separation holding member 151R, to rotatably support the separation holding member 151R. Here, the swing center of the separation holding member 151R assembled to the development cover member 128 is the separation holding member swing axis H. The development cover member includes a first retaining portion 128d which 20 projects in the direction of the separation holding member swing axis H. As shown in Figure 15, the movement of the separation holding member 151R assembled to the development cover member 128 in the swing axis H direction is restricted by abutment of the first retaining portion 128d to the separation holding member 151R. 25

[0313] Further, the outer diameter of the second support portion 128k fits with the inner wall of the oblong support receiving portion 152Ra of the force applying member 152R, to support the force applying member 152R so as to be 2026249127   12 Oct 2026 rotatable and movable in the oblong direction. Here, the swing center of the force applying member 152R assembled to the development cover member 128 is a force applying member swing axis HC. As shown in Figure 15, the movement of the force applying member 152R assembled to the development cover member 5   128 in the swing axis HC direction is restricted by abutment of the second retaining portion 128m to the separation holding member 151R.

[0314] Figure 10 is a sectional view taken along a line CS with a part of the driving side cartridge cover member 116 and a part of the development cover member 128 omitted such that the fitting portion between the oblong support 10 receiving portion 151Ra of the force applying member 152R and the cylindrical portion 128b of the development cover member 128 can be seen. The separation contact mechanism 150R is provided with a tension spring 153, as an urging means, for urging the separation holding member 151R to rotate in the direction of arrow B1 in the drawing about the separation holding member swing 15 axis H and for urging the force applying member 152R in the direction of arrow B3.

[0315] The arrow B3 direction is a direction substantially parallel to the oblong direction LH2 (see Figure 18) of the oblong support receiving portion 152Ra of the force applying member 152R. The tension spring 153 is 20 assembled between the spring hooked portion 151Rg provided on the separation holding member 151R and the spring hooked portion 152Rs provided on the force applying member 152R. The tension spring 153 applies a force to the spring hooked portion 151Rg of the separation holding member 151R in the direction of arrow F2 in Figure 10 to apply an urging force for rotating the 25 separation holding member 151R in the direction of arrow B1. Further, the tension spring 153 applies a force to the spring hooked portion 152Rs of the force applying member 152R in the direction of the arrow F1 to apply an urging force 2026249127   12 Oct 2026 for moving the force applying member 152R in the direction of the arrow B3.

[0316] The line connecting the spring hooked portion 151Rg of the separation holding member 151R and the spring hooked portion 152Rs of the force holding member 152R is GS. The line connecting the spring hooked portion 152Rs of 5 the force applying member 152R and the force applying member swing axis HC is HS. Here, a angle 02 formed by the line GS and the line HS is selected to satisfy the following equation (2) with the clockwise direction about the spring hooked portion 152Rs of the force applying member 152R being positive. By this, the force applying member 152R is urged to rotate in the direction of arrow 10 BA about the force applying member swing axis HC. 0° ^0 2^90° ...(2)

[0317] As shown in Figure 15, in the development drive input gear 132, the inner diameter portion of the cylindrical portion 128b of the development cover member 128 and the outer diameter portion of the cylindrical portion 32b of the 15 development drive input gear 132 are fitted, and in addition, the support portion 126a of the driving side bearing 126 is fitted and the cylindrical portion (not shown) of the development drive input gear are fitted. By this, the driving force can be transmitted to the developing roller gear 131, the toner feeding roller gear 133, and other gears. 20

[0318] In this embodiment, the mounting positions of the separation holding member 151R and the force applying member 152R are as follows. As shown in Figure 15, in the direction of the swing axis K, the separation holding member 151R is disposed on the side (outside in the longitudinal direction) where the driving side cartridge cover member 116 is provided, with the development cover 25 member 128 interposed therebetween. The force applying member 152R is disposed on the side (inside in the longitudinal direction) where the development drive input gear 13 is arranged. However, the position thereof is not limited to 2026249127   12 Oct 2026 this, and the positions of the separation holding member 151R and the force applying member 152R may be interchanged, and the separation holding member 151R and the force applying member 152R may be disposed in one side in the swing axis K direction with respect to the development cover member 128. 5 Further, the arrangement order of the separation holding member 151R and the force applying member 152R may be exchanged.

[0319] The development cover member 128 is fixed to the development frame 125 by way of the driving side bearing 126 to form the developing unit 109. As shown in Figure 15, the fixing method in this embodiment uses a fixing screw 10   145 and an adhesive (not shown), but the fixing method is not limited to this example, and welding such as welding by heating or pouring and hardening of resin material, for example, may be used.

[0320] Here, Figure 20 is a sectional view in which the periphery of the separation holding portion 151R in Figure 10 is enlarged and a part of the tension 15 spring 153 and the separation holding member 151R is partially omitted by the partial sectional line CS4 for the sake of illustration. In the force applying member 152R, the first restriction surface 152Rv of the force applying member 152R comes into contact with the first restriction surface 128h of the development cover member 128 by the urging force of the tension spring 153 in 20 the F1 direction in the drawing, as described above. Further, the second restriction surface 152Rw of the force applying member 152R comes into contact with the second restriction surface 128q of the development cover member 128 and is positioned thereby. This position is referred to as an accommodation position (reference position) of the force applying member 152R. Further, the 25 separation holding member 151R is rotated in the B1 direction about the swing axis H of the separation holding member by the urging force of the tension spring 153 in the F2 direction, and the second pressed portion 151Rd of the separation 2026249127   12 Oct 2026 holding member 151R comes into contact with the second pressing surface 152Rr of the force applying member 152R, by which the rotation is stopped. This position is referred to as a separation holding position (restriction position) of the separation holding member 151R. 5

[0321] Further, Figure 21 is an illustration in which the periphery of the separation holding portion 151R in Figure 10 is enlarged, and the tension spring 153 is omitted, for the sake of illustration. Here, the case is considered in which the process cartridge 100 including the separation contact mechanism 150R according to this embodiment is dropped in the JA direction of Figure 21 when 10 the process cartridge 100 is transported. At this time, the separation holding member 151R receives a force of rotating in the direction of arrow B2 by its own weight about the separation holding swing axis H. For this reason, when the rotation in the B2 direction occurs starts,, the rotation prevention surface 151Rn of the separation holding member 151R comes into contact with the locking 15 surface 152Ru of the force applying member 152R, and the separation holding member 151R receives the force in the F3 direction in the drawing so as to suppress the rotation in the B2 direction. By this, it is possible to prevent the separation holding member 151R from rotating in the B2 direction during transportation, and it is possible to prevent the state of separation between the 20 photosensitive drum 104 and the developing unit 109 from being impaired.

[0322] In this embodiment, the tension spring 153 is mentioned as an urging means for urging the separation holding member 151R to the separation holding position and for urging the force applying member 152R to the accommodating position, but the urging means is not limited to this example. For example, a 25 torsion coil spring, a leaf spring, or the like may be used as an urging means to urge the force applying member 152R to the accommodating position and to urge the separation holding member 151R to the separation holding position. Further, 2026249127   12 Oct 2026 the material of the urging means may be metal, a mold, or the like, which has elasticity and can urge the separation holding member 151R and the force applying member 152R.

[0323] As described above, the developing unit 109 provided with the 5 separation contact mechanism 150R is integrally coupled with the drum holding unit 108 by the driving side cartridge cover member 116 as described above (state in Figure 19).

[0324] Figure 22 is a view as seen in the direction of arrow J in part (a) of Figure 19s shown in Figure 15, the driving side cartridge cover 116 of this 10 embodiment has a contact surface 116c. As shown in Figure 22, the contact surface 116c is slanted with an inclination of an angle 03 relative to the swing axis K. It is desirable that the angle 03 is the same as the angle 01 forming the separation holding surface 151Rc of the separation holding member 151R, but the angle 03 is not limited to this example. Further, as shown in Figures 15 and 15 19when the driving side cartridge cover member 116 is assembled to the developing unit 109 and the drum holding unit 108, the contact surface 116c faces the separation holding surface 151Rc of the separation holding member 151R placed at a separation holding position. The contact surface 116c contacts the separation holding surface 151Rc by the urging force of the development 20 pressure spring 134 which will be described hereinafter. The structure is such that when the engaging surface 116Rc and the separation holding surface 151Rc contact each other, the attitude of the developing unit 109 is positioned so that the developing roller 106 of the developing unit 109 and the photosensitive drum 104 are separated by a gap P1. The state in which the developing roller 106 25 (developing member) is separated from the photosensitive drum 104 by the gap P1 by the separation holding member 151R is referred to as a separation position (retraction position) of the developing unit 109 (see part (a) of Figure 42). 2026249127   12 Oct 2026

[0325] Here, referring to Figure 42, the separated state and the contact state of the process cartridge 100 will be described in detail.

[0326] Figure 42 is a side view of the process cartridge 100 as viewed from the driving side with the process cartridge 100 mounted inside the image forming 5 apparatus main assembly 170. Part (a) of Figure 42 shows a state in which the developing unit 109 is separated from the photosensitive drum 104. Part (b) of Figure 42 shows a state in which the developing unit 109 is in contact with the photosensitive drum 104.

[0327] First, in a state where the separation holding member 151R is placed at 10 the separation holding position and the developing unit 109 is located at the separation position, the pressed portion 152Re of the force applying member 152R is pushed in the ZA direction. By this, the projecting portion 152Rh of the force applying member 152R projects from the process cartridge 100. The second pressed surface 151Re of the separation holding member 151R is in 15 contact with the second pressing surface 152Rr of the force applying member 152R by the tension spring 153 as described above. Therefore, when the second force receiving portion 152Rn is pressed in the direction of the arrow W42, the force applying member 152R rotates in the direction of the arrow BB about the force applying member swing axis HC to rotate the separation holding member 20   151R in the direction of the arrow B2. When the separation holding member 151R rotates in the direction of arrow B2, the separation holding surface 151Rc separates from the contact surface 116c, by which the developing unit 109 can rotate from the separation position in the direction of arrow V2 about the swing axis K. That is, the developing unit 109 rotates in the V2 direction from the 25 separated position, and the developing roller 106 of the developing unit 109 comes into contact with the photosensitive drum 104. Here, the position of the developing unit 109 in which the developing roller 106 and the photosensitive 2026249127   12 Oct 2026 drum 104 contact each other is referred to as a contact position (development position) (state of part (b) of Figure 42. The position where the separation holding surface 151Rc of the separation holding member 151R is separated from the contact surface 116c is referred to as a separation permission position 5 (permission position). When the developing unit 109 is located at the contact position, the second restriction surface 151Rk of the separation holding member 151R contacts the second restriction surface 116d of the driving side cartridge cover 116, so that the separation holding member 151R is maintained at the separation release position. 10

[0328] Further, the driving side bearing 126 has a first pressed surface 126c which is a surface perpendicular to the swing axis K. Since the driving side bearing 126 is fixed to the developing unit 109, the developing unit 109 presses the first force receiving portion 152Rk of the force applying member 152R in the direction of the arrow 41 in the state that the developing unit is in the contact 15 position. Then, by the first pressing surface 152Rq being brought into contact with the first pressed surface 126c, the developing unit 109 rotates about the swing axis K in the direction of arrow V1 to move to a separated position (state shown in part (a) of Figure 42). Here, the direction in which the first force receiving surface 126c moves when the developing unit 109 moves from the 20 contact position to the separated position is shown by arrows W41 in part (a) of Figures 42 and 42 (b). Further, the direction opposite to the arrow W41 is depicted by an arrow W42, and the arrow W41 direction and the arrow W42 direction are substantially horizontal (X1, X2 directions). The second force receiving surface 152Rp of the force applying member 152R assembled to the 25 developing unit 109 as described above is on the upstream side of the first force receiving surface 126c of the driving side bearing 126 in the direction of the arrow W41. Further, the first force receiving surface 126c and the second force 2026249127   12 Oct 2026 receiving surface 151Re of the separation holding member 151R are disposed at positions where they overlap at least partly in the W1 and W2 direction.

[0329] The detailed description of the operation of the separation contact mechanism 150R in the image forming apparatus main assembly 170 will be 5 made below. [Mounting of process cartridge to image forming apparatus main assembly]

[0330] Next, referring to Figures 12, 23, and 24 the description will be made as to the engaging operation of 195 between the separation contact mechanism 10   150R of the process cartridge 100 and the development separation control unit of the image forming apparatus main assembly 170 when the process cartridge 100 is mounted to the image forming apparatus main assembly 170. For the sake of illustration, these Figures are sectional views in which a part of the development cover member 128 and a part of the driving side cartridge cover member 116 are 15 omitted along the partial sectional lines CS1 and CS2, respectively.

[0331] Figure 23 is a view as seen from the driving side of the process cartridge 100 when the process cartridge 100 is mounted on the cartridge tray 171 (not shown) of the image forming apparatus M and the cartridge tray 171 is inserted into the first mounting position. In this Figure, except for the process 20 cartridge 100, the cartridge pressing unit 121, and the separation control member 196R are omitted.

[0332] As described above, the image forming apparatus main assembly 170 of this embodiment includes the separation control member 196R corresponding to each process cartridge 100 as described above. The separation control 25 members 196R are arranged on the lower side of the image forming apparatus main assembly 170 below the separation holding member 151R when the process cartridge 100 is placed at the first inner position and the second inner position. 2026249127   12 Oct 2026 The separation control member 196R has a first force applying surface 196Ra and a second force applying surface 196Rb which project toward the process cartridge 100 and face each other across the space 196Rd. The first force applying surface 196Ra and the second force applying surface 196Rb are 5 connected with each other by way of a connecting portion 196Rc in the lower side of the image forming apparatus main assembly 170. Further, the separation control member 196R is supported by the control sheet metal 197 rotatably about a rotation center 196Re. The separating member 196R is normally urged in an E1 direction by an urging spring. Further, the control sheet metal 197 is 10 structured to be movable in the W41 and W42 directions by a control mechanism (not shown), so that the separation control member 196R is structured to be movable in the W41 and W42 directions.

[0333] As described above, in interrelation with the transition of the front door 11 of the image forming apparatus main assembly 170 from the open state to the 15 closed state, the cartridge pressing unit 121 lowers in the direction of arrow ZA, and the first force applying portion 121a is brought into contact with the pressed surface 152Rf of the force applying member 152R. After that, when the cartridge pressing unit 121 is lowered to a predetermined position which is the second mounting position, the projecting portion 152Rh of the force applying 20 member 152R projects downward in the Z2 direction of the process cartridge 100 (state in Figure 24). This position is referred to as a projecting position of the force applying member 152R. When this operation is completed, as shown in Figure 24, a gap T4 is formed between the first force applying surface 196Ra of the separation control member 196R and the first force receiving surface 152Rp 25 of the force applying member 152R, and a gap T3 is formed between the second force applying surface 196Rb and the second force receiving surface 152Rp. Then, it is placed at the second mounting position where the separation control 2026249127   12 Oct 2026 member 196R does not act on the force applying member 152R. This position of the separation control member 196R is referred to as a home position. The arrangement is such that at this time, the first force receiving surface 152Rp of the force applying member 152R and the first force applying surface 196Ra of 5 the separation control member 196R are partly overlapped in the W1 and W2 direction. Similarly, the arrangement is such that the second force receiving surface 152Rp of the force applying member 152R and the second force applying surface 196Rb of the separation control member 196R are partly overlapped in the W1 and W2 direction. 10 [Contact operation of developing unit]

[0334] Next, referring to Figures 24 to 26,, the detailed description will be made as to the operation of contacting between the photosensitive drum 104 and the developing roller 106 by the separation contact mechanism 150R. For the 15 sake of illustration, these Figures are sectional views of a part of the development cover member 128, a part of the driving side cartridge cover member 116, and a part of the driving side bearing 126, taken along lines CS1, CS2 and CS3, respectively.

[0335] In the structure of this embodiment, the development input coupling 32 20 receives a driving force from the image forming apparatus main assembly 170 in the direction of arrow V2 in Figure 24, so that the developing roller 106 rotates. That is, the developing unit 109 including the developing input coupling 32 receives torque in the arrow V2 direction about the swing axis K from the image forming apparatus main assembly 170. As shown in Figure 24, when the 25 developing unit 109 is in the separated position and the separation holding member 151R is in the separation holding position, the developing unit 109 receives this torque and an urging force by the development pressure spring 134 2026249127   12 Oct 2026 as will be described hereinafter. Even in this case, the separation holding surface 151Rc of the separation holding member 151R contacts the contact surface 116c of the driving side cartridge cover member 116, and therefore, the attitude of the developing unit 109 is maintained at the separation position. 5

[0336] The separation control member 196R of this embodiment is structured to be movable in the direction of arrow W42 in Figure 24 from the home position. When the separation control member 196R moves in the W42 direction, the second force applying surface 196Rb of the separation control member 196R and the second force receiving surface 152Rp of the force applying member 152R 10 come into contact with each other, so that the force applying member 152R rotates about the swing axis HC of the force applying member 152R in the BB direction. Further, as the force applying member 152R rotates further, the separation holding member 151R is rotated in the B2 direction, while the second pressing surface 152Rr of the force applying member 152R contacts the second 15 pressed surface 151Re of the separation holding member 151R. Then, the separation holding member 151R is rotated by the force applying member 152R to the separation permission position where the separation holding surface 151Rc and the contact surface 116c are separated from each other. Here, the position of the separation control member 196R for moving the separation holding 20 member 151R to the separation permission position shown in Figure 25 is referred to as a first position.

[0337] In this manner, the separation control member 196R moves the separation holding member 151R to the separation permission position. Then, the developing unit 109 is rotated in the V2 direction by the torque received from 25 the image forming apparatus main assembly 170 and the development pressure spring 134 which will be described hereinafter, and moves to the contact position where the developing roller 106 and the photosensitive drum 104 are in contact 2026249127   12 Oct 2026 with each other (state shown in Figure 25). At this time, the separation holding member 151R urged in the direction of arrow B1 by the tension spring 153 is maintained at the separation permission position by the second restricted surface 151Rk coming into contact with the second restriction surface 116d of the driving 5 side cartridge cover member 116. Thereafter, the separation control member 196R moves in the direction of W41 and returns to the home position. At this time, the force applying member 152R is rotated in the BA direction by the tension spring 153, and the first pressing surface 152Rq of the force applying member 152R and the first pressing surface 126c of the driving side bearing 126 10 become in contact with each other (state shown in Figure 26).

[0338] By this, the above-mentioned gaps T3 and T4 are formed again, and are placed at positions where the separation control member 196R does not act on the force applying member 152R. The transition from the state of Figure 25 to the state of Figure 26 is performed without a delay. 15

[0339] As described above, in the structure of this embodiment, by the separation control member 196R moving from the home position to the first position, the force applying member 152R can be rotated and the separation holding member 151R is moved from the separation holding position to the separation permission position. By this, the developing unit 109 can move from 20 the separated position to the contacting position where the developing roller 9 and the photosensitive drum 104 are in contact with each other. The position of the separation control member 196R in Figure 26 is the same as that in Figure 24. [Separation operation of developing unit] 25

[0340] Next, referring to Figures 26 and 27, the operation of moving the developing unit 109 from the contact position to the distance position by the separation contact mechanism 150R will be described in detail. For the sake of 2026249127   12 Oct 2026 better illustration, these Figures are cross-sectional views taken along the line CS, in which a part of the development cover member 128, a part of the driving side cartridge cover member 116, and a part of the driving side bearing 126 are partially omitted. 5

[0341] The separation control member 196R in this embodiment is structured to be movable from the home position in the direction of arrow W41 in Figure 26. When the separation control member 196R moves in the W41 direction, the first force applying surface 196Rb and the first force receiving surface 152Rm of the force applying member 152R are brought into contact with each other, and the 10 force applying member 152R rotates about the force applying member swing axis HC in the direction indicated by the arrow BB. Rotate in the direction. Then, the developing unit 109 rotates from the contact position in the direction of the arrow V1 about the swing axis K, by the first pressing surface 152Rq of the force applying member 152R being brought into contact with the first pressed surface 15   126c of the driving side bearing 126 (State shown in Figure 27). Here, the pressed surface 152Rf of the force applying member 152R has the arc shape, and the center of the arc is placed so as to coincide with the swing axis K. By this, when the developing unit 109 moves from the contact position to the separated position, the force received by the pressed surface 152Rf of the force applying 20 member 152R from the cartridge pressing unit 121 is directed in the swing axis K direction. Therefore, the developing unit 109 can be operated so as not to hinder the rotation in the arrow V1 direction. In the separation holding member 151R, the second restricted surface 151Rk of the separation holding member 151R and the second restriction surface 116d of the driving side cartridge cover member 25   116 are separated from each other, and the separation holding member 151R is rotated in the arrow B1 direction by the urging force of the tension spring 153. By this, the separation holding member 151R rotates until the second pressed 2026249127   12 Oct 2026 surface 151Re comes into contact with the second pressing surface 152Rr of the force applying member 152R, and by the contacts, the separation holding member 151R shifts to the separation holding position. When the developing unit 109 is moved from the contact position to the separation position by the 5 separation control member 196R and the separation holding member 151R is in the separation holding position, the gap T5 is formed between the separation holding surface 151Rc and the contact surface 116c as shown in Figure 27,. Here, the position shown in Figure 27 in which the developing unit 109 is rotated from the contact position toward the separation position and the separation 10 holding member 151 can move to the separation holding position is referred to as a second position of the separation control member 196R.

[0342] Thereafter, the separation control member 196R moves in the direction of the arrow W42 and returns from the second position to the home position. Then, while the separation holding member 151R is maintained in the separation 15 holding position, the developing unit is rotated in the arrow V2 direction by the torque received from the image forming apparatus main assembly 170 and the development pressure spring 134 which will be described hereinafter, and the separation holding surface 151Rc is contacted to the contact surface 116c. That is, the developing unit 109 is in a state where the separation position is 20 maintained by the separation holding member 151R, and the developing roller 106 and the photosensitive drum 104 are in a state where they are separated by a gap P1 (states shown in Figure 24 and part (a) of Figure 42. By this, the abovementioned gaps T3 and T4 are formed again, and the separation control member 196R is placed at a position not acting on the force applying member 152R (state 25 in Figure 24). The transition from the state of Figure 27 to the state of Figure 24 is executed without a delay.

[0343] As described above, in this embodiment, the separation control 2026249127   12 Oct 2026 member 196R moves from the home position to the second position, so that the separation holding member 151R moves from the separation permission position to the separation holding position. Then, by the separation control member 196R returning from the second position to the home position, the developing 5 unit 109 becomes in a state of maintaining the separation position by the separation holding member 151R. [Detailed description of separation holding member L]

[0344] Here, referring to Figure 28, the separation holding member 151L will 10 be described in detail.

[0345] Part (a) of Figure 28 is a front view of the process cartridge 100 per se of the separation holding member 151L as viewed in the longitudinal direction of the driving side, and Figures 28B and 28C are perspective views of the separation holding member 151L per se. The separation holding member 151L includes an 15 annular support receiving portion 151La, and includes a separation holding portion 151Lb projecting from the support receiving portion 151La in the radial direction of the support receiving portion 151La. The free end of the separation holding portion 151Lb has an arc-shaped separation holding surface 151Lc extending about the separation holding member swing axis H. 20

[0346] Further, the separation holding member 151L has a second regulated surface 151Lk adjacent to the separation holding surface 151Lc. Further, the separation holding member 151L includes a second pressed portion 151Ld projecting from the support receiving portion 151La in the Z2 direction, and includes a arc-shaped second pressed surface 151Le projecting from the second 25 pressed portion 151Ld in the direction of the separation holding member swing axis H of the support receiving portion 151La.

[0347] Further, the separation holding member 151L is provided with a main 2026249127   12 Oct 2026 body portion 151Lf connected with the support receiving portion 151La, and the main body portion 151Lf is provided with a spring hooked portion 151Lg projecting in the direction of the separation holding member swing axis H of the support receiving portion 151La. Further, the main body portion 151Lf is 5 provided with a rotation prevention portion 151m projecting in the Z2 direction, and a rotation prevention surface 151Ln is provided in a direction facing the second pressed surface 151Le. [Detailed description of force applying member L] 10

[0348] Referring to Figure 29, the force applying member 152L will be described in detail.

[0349] Part (a) of Figure 29 is a front view of the force applying member 152L as viewed in the longitudinal direction of the process cartridge 100, and parts (b) and (c) of Figure 29 are perspective views of the force applying member 152L. 15

[0350] The force applying member 152L is provided with an oblong-shaped oblong support receiving portion 152La. Here, the longitudinal direction of the oblong shape of the oblong support receiving portion 152La is depicted by an arrow LH, the upward direction is depicted by an arrow LH1, and the downward direction is depicted by an arrow LH2. Further, the direction in which the 20 oblong support receiving portion 152La is extended is depicted by HD. The force applying member 152L is provided with a projecting portion 152Lh formed on the downstream side in the arrow LH2 direction of the oblong support receiving portion 152La. The oblong support receiving portion 152La and the projecting portion 152Lh are connected by a main body portion 152Lb with each 25 other. On the other hand, the force applying member 152L includes a pushed portion 152Le projecting in the direction of arrow LH1 and in the direction substantially perpendicular to the direction of arrow LH1, and is provided with an 2026249127   12 Oct 2026 arc-shaped pressed surface 152Lf on the downstream side in the arrow LH1 direction and is further provided with a pushing restriction surface of 152Lg on the upstream side. Further, the force applying member 152L has a first at-accommodation restriction surface 152Lv which is a part of the oblong support 5 receiving portion 152La and which is provided on the downstream side in the arrow LH2 direction.

[0351] The projecting portion 152Lh includes a first force receiving portion 152Lk and a second force receiving portion 152Ln which are arranged so as to oppose each other in a direction substantially perpendicular to the arrow LH2 10 direction and a terminal portion in the arrow LH2 direction. The first force receiving portion 152Lk and the second force receiving portion 152Ln have a first force receiving surface 152Lm and a second force receiving surface 152Lp extending in the HD direction and having an arc shape, respectively. In addition, the projecting portion 152Lh is provided with a spring hooked portion 152Ls and 15 a locking portion 152Lt projecting in the HB direction, and the locking portion 152Lt is provided with a locking surface 152Lu facing in the same direction as the second force receiving surface 152Lp.

[0352] Further, the force applying member 152L is a part of the main body portion 152Lb, is placed on the upstream side of the second force receiving 20 portion 152Ln in the arrow LH2 direction, and has a first pressing surface 152Lq facing in the same direction as the second force receiving surface 152Lp. Further, the force applying member 152L is a part of the main body portion 152Lb, is placed on upstream side of the first force receiving portion 152Lk in the arrow LH2 direction, and has a first pressing surface 152Lr facing in the same 25 direction as the first force receiving surface 152Lm.

[0353] In the state that the process cartridge 100 is mounted to the image forming apparatus main assembly 170, the LH1 direction is substantially the 2026249127   12 Oct 2026 same as the Z1 direction, and the LH2 direction is substantially the same as the Z2 direction. Further, the HB direction is substantially the same as the longitudinal direction of the process cartridge 100. 5 [Assembling of separation / contact mechanism L]

[0354] Next, referring to Figures 16 and 29 to 35, the assembly of the separation mechanism will be described. Figure 30 is a perspective view of the process cartridge 100 after assembling the separation holding member therewith, as viewed from the driving side. As described above, as shown in Figure 16, in 10 the developing unit 109, the outer diameter portion of the cylindrical portion 127a of the non-driving side bearing 127 is fitted into the developing unit support hole portion 117a of the non-driving side cartridge cover member 117. By this, the developing unit 109 is supported so as to be rotatable relative to the photosensitive drum 104 about the swing axis K. Further, the non-driving side 15 bearing 127 includes a cylindrical first support portion 127b and a second support portion 127e projecting in the direction of the swing axis K.

[0355] The outer diameter of the first support portion 127b fits with the inner diameter of the support receiving portion 151La of the separation holding member 151L, to rotatably support the separation holding member 151L. Here, 20 the swing center of the separation holding member 151L assembled to the nondriving side bearing 127 is the separation holding member swing axis H. The non-driving side bearing 127 includes a first retaining portion 127c projecting in the direction of the separation holding member swing axis H. As shown in Figure 16, the movement of the separation holding member 151L assembled to 25 the non-driving side bearing 127 in the swing axis H direction is restricted by the first retaining portion 127c coming into contact with the separation holding member 151L. 2026249127   12 Oct 2026

[0356] Further, the outer diameter of the second support portion 127e fits with the inner wall of the oblong support receiving portion 152La of the force applying member 152L, to support the force applying member 152L so as to be rotatable and movable in the oblong direction. Here, the swing center of the 5 force applying member 152L assembled to the non-driving side bearing 127 is the force applying member swing axis HC. As shown in Figure 16, the movement of the force applying member 152L assembled to the non-driving side bearing 127 in the direction of the swing axis HE is restricted by the second retaining portion 127f coming into contact with the separation holding member 151L. 10

[0357] Figure 31 is a view of the process cartridge 100 after being assembled with the separation holding member 151L as viewed in the developing unit swing axis H direction. It is a view taken along a line CS with a part of the nondriving side cartridge cover member 117 omitted so that the fitting portion between the oblong support receiving portion 151La of the force applying 15 member 152L and the cylindrical portion 127e of the non-driving side bearing 127 can be seen. Here, the separation contact mechanism 150L is provided with a tension spring 153 for urging the separation holding member 151L to rotate in the direction of arrow B1 about the separation holding member swing axis H and for urging the force applying member 152L in the direction of arrow B3. The 20 arrow B3 direction is a direction substantially parallel to the longitudinal direction LH2 (see Figure 29) of the oblong support receiving portion 152La of the force applying member 152L. The tension spring 153 is assembled between the spring hooked portion 151Lg provided on the separation holding member 151L and the spring hooked portion 152Ls provided on the force applying 25 member 152L. The tension spring 153 applies a force to the spring hooked portion 151Lg of the separation holding member 151L in the direction of arrow F2 in Figure 31 to apply an urging force for rotating the separation holding 2026249127   12 Oct 2026 member in the direction of arrow B1. Further, the tension spring 153 applies a force to the spring hooked portion 152Ls of the force applying member 152L in the direction of the arrow F1 to apply an urging force for moving the force applying member 152L in the direction of the arrow B3. 5

[0358] The line connecting the spring hooked portion 151Lg of the separation holding member 151L and the spring hooked portion 152Ls of the force holding member 152L is GS. The line connecting the spring hooked portion 152Ls of the force applying member 152L and the force applying member swing axis HE is HS. A angle 03 formed by the line GS and the line HE is selected to satisfy 10 the following inequity (3) with the counterclockwise direction being positive about the spring hooked portion 152Ls of the force applying member 152L. By this, the force applying member 152L is urged to rotate in the BA direction in the drawing about the force applying member swing axis HE. 0° ^0 3^90° ...(3) 15

[0359] In this embodiment, the mounting positions of the separation holding member 151L and the force applying member 152L are as follows. As shown in Figure 29, in the direction of the swing axis K, the separation holding member 151L and the force applying member 152L are disposed on the side (longitudinal outside) where the non-driving side cartridge cover member 117 of the non- 20 driving side bearing 127 is placed. However, the positions to be arranged are not limited to the examples, and they may be provided on the development frame 125 side (inside in the longitudinal direction) of the non-driving side bearing 127, and the separation holding member 151L and the force applying member 152L may be provided with the non-driving side bearing 127 interposed therebetween. 25 Further, the arrangement order of the separation holding member 151L and the force applying member 152L may be interchanged.

[0360] The non-driving side bearing 127 is fixed to the development frame 2026249127   12 Oct 2026 125 to form the developing unit 109. As shown in Figure 16, in the fixing method in this embodiment, a fixing screw 145 and an adhesive (not shown), but the fixing method is not limited to this example, and welding such as welding by heating or pouring and hardening of resin can be employed. 5

[0361] Part (a) of Figure 32 and part (b) of Figure 32 are sectional views in which a portion of the non-driving side cartridge cover member 117, the tension spring 153, and the separation holding member 151L is partially omitted by the partial sectional line CS. For the sake of explanation, in part (a) of Figure 32 and part (b) of Figure 32 the parts around the force applying member swing axis 10 HE and the separation holding portion 151L of the force applying member 152L shown in Figure 31 is enlarged.

[0362] In the force applying member 152L, the first restriction surface 152Lv of the force applying member 152L comes into contact with the second support 15 portion 127e of the non-driving side bearing 127 by the urging force of the tension spring 153 in the arrow F1 direction. Further, as shown in part (b) of Figure 32, the first pressing surface 152Lq of the force applying member 152L contacts the first pressed surface 127h of the non-driving side bearing 127 to be positioned in place. This position is referred to as an accommodation position 20 (reference position) of the force applying member 152L. Further, the separation holding member 151L is rotated in the direction of the arrow B1 about the swing axis H of the separation holding member by the urging force of the tension spring 153 in the arrow F2 direction, and the contact surface 151Lp of the separation holding member 151L is brought into contact with the second pressing surface 25   152Lr of the force applying member 152L, by which it is positioned in place. This position is referred to as a separation holding position (restricted position) of the separation holding member 151L. When the force applying member 152L 2026249127   12 Oct 2026 moves to the projecting position which will be described hereinafter, the second pressed surface 151Le of the separation holding member 151L contacts the second pressing surface 152Lr of the force applying member 152L to be positioned at the separation holding position. 5

[0363] Further, Figure 33 is an illustration in which the periphery of the separation holding portion 151L in Figure 31 is enlarged for the sake of illustration, and the tension spring 153 is omitted. Here, the consideration will be made as to the case where the process cartridge 100 including the separation contact mechanism 150L is dropped in the direction of arrow JA in Figure 33 10 when the process cartridge 100 is transported. At this time, the separation holding member 151L receives a force of rotating in the direction of arrow B2 due to its own weight around the separation holding swing axis H. When the separation holding member 151L starts to rotate in the arrow B2 direction, for the above reason, the rotation prevention surface 151Ln of the separation holding 15 member 151L comes into contact with the locking surface 152Lu of the force applying member 152L, and the separation holding member 151L receives the force in the direction F4 of suppressing the rotation in the arrow B2 direction. By this, it is possible to prevent the separation holding member 151L from rotating in the direction of the arrow B2 during transportation, and it is possible 20 to prevent impairment of the state of separation between the photosensitive drum 104 and the developing unit 109.

[0364] In this embodiment, the tension spring 153 is mentioned as an urging means for urging the separation holding member 151L to the separation holding position and the force applying member 152L to the accommodation position, but 25 the urging means is limited to this example. For example, a torsion coil spring, a leaf spring, or the like may be used as an urging means to urge the force applying member 152L to the accommodation position and to urge the separation 2026249127   12 Oct 2026 holding member 151L to the separation holding position. Further, the material of the urging means may be metal, a mold, or the like, which has elasticity and can urge the separation holding member 151L and the force applying member 152L. 5

[0365] As described above, the developing unit 109 provided with the separation contact mechanism 150L is integrally coupled with the drum holding unit 108 by the non-driving side cartridge cover member 117 as described above (state in Figure 30). As shown in Figure 16, the non-driving side cartridge cover 117 of this embodiment has a contact surface 117c. The contact surface 117c is 10 a surface parallel to the swing axis K. Further, as shown in Figures 16 and 30when the non-driving side cartridge cover member 117 is assembled to the developing unit 109 and the drum holding unit 108, the contact surface 117c faces the separation holding surface 151Lc of the separation holding member 151L placed at a separation holding position. 15

[0366] Here, the process cartridge 100 includes a development pressure spring 134 as an urging member for bringing the developing roller 106 into contact with the photosensitive drum 104. The development pressure spring 134 is assembled between the spring hooked portion 117e of the non-driving side cartridge cover member 117 and the spring hooked portion 127k of the non- 20 driving side bearing 127. The urging force of the development pressure spring 134 causes the separation holding surface 151Lc of the separation holding member 151L and the contact surface 117c of the non-driving side cartridge cover member 117 to contact each other. Then, when the contact surface 117cc and the separation holding surface 151Lc contact each other, the attitude of the 25 developing unit 109 is positioned so that the developing roller 106 of the developing unit 109 and the photosensitive drum 104 are spaced by a gap P1. The state in which the developing roller 106 is spaced from the photosensitive 2026249127   12 Oct 2026 drum 104 by the gap P1 by the separation holding member 151L is referred to as a separation position (retracted position) of the developing unit 109 (see part (a) of Figure 35.

[0367] Here, referring to Figure 35, the separated state and the contact state of 5 the process cartridge 100 will be described in detail. Figure 35 is a side view of the process cartridge 100 as viewed from the non-driving side with the process cartridge 100 mounted inside the image forming apparatus main assembly 170. Part (a) of Figure 35 shows a state in which the developing unit is separated from the photosensitive drum 104. Part (b) of Figure 35 shows a state in which the 10 developing unit 109 is in contact with the photosensitive drum 104.

[0368] First, in a state in which the separation holding member 151L is placed at the separation holding position and the developing unit 109 is placed at the separation position, the pushed portion 152Le of the force applying member 152L is pushed in the direction of arrow ZA. By this, the projecting portion 152Lh of 15 the force applying member 152L projects from the process cartridge 100 (state of part (a) of Figure 34. This position is referred to as a projecting position of the force applying member 152L. The second pressed surface 151Le of the separation holding member 151L is in contact with the second pressing surface 152Lr of the force applying member 152L by the tension spring 153 as described 20 above. Therefore, when the second force receiving portion 152Ln is pressed in the direction of the arrow W42, the force applying member 152L rotates in the direction of the arrow BD about the force applying member swing axis HE to rotate the separation holding member 151L in the direction of the arrow B5. When the separation holding member 151L rotates in the direction of arrow B5, 25 the separation holding surface 151Lc separates from the contact surface 117c, and the developing unit 109 becomes capable of rotating from the separation position in the direction of arrow V2 about the swing axis K. 2026249127   12 Oct 2026

[0369] That is, the developing unit 109 rotates in the V2 direction from the separated position, and the developing roller 106 of the developing unit 109 comes into contact with the photosensitive drum 104. Here, the position of the developing unit 109 in which the developing roller 106 and the photosensitive 5 drum 104 contact each other is referred to as a contact position (development position) (state of part (b) of Figure 34. The position where the separation holding surface 151Lc of the separation holding member 151L is separated from the contact surface 117c is referred to as a separation permission position (permission position). When the developing unit 109 is placed at the contact 10 position, by the second restriction surface 151Lk of the separation holding member 151L contacting the second restriction surface 117d of the driving side cartridge cover 116, the separation holding member 151L is maintained at the separation permission position.

[0370] Further, the non-driving side bearing 127 of this embodiment has a first 15 pressed surface 127h which is a surface perpendicular to the swing axis K. Since the non-driving side bearing is fixed to the developing unit 109, the developing unit 109 presses the first force receiving portion 152Lk of the force applying member 152L in the direction of the arrow 41 while the developing unit 109 is in the contact position. Then, by the first pressing surface 152Lq coming 20 into contact with the first pressed surface 127h, the developing unit is rotated about the swing axis K in the direction of arrow V1 and moves to a separated position (state shown in part (a) of Figure 34). Here, when the developing unit 109 moves from the contact position to the separated position, the direction in which the first pressed surface 127h moves is indicated by an arrow W41 in part 25    (a) of Figure 34 and part (b) of Figure 34. Further, the direction opposite to the arrow W41 is indicated by the arrow W42, and the directions of the arrow W41 and the arrow W42 are substantially horizontal directions (X1, X2 directions). 2026249127   12 Oct 2026 The second force receiving surface 152Lp of the force applying member 152L assembled to the developing unit 109 as described above is placed on the upstream side of the first pressed surface 127h of the non-driving side bearing 127 in the direction of the arrow W41. In addition, the first pressed surface 5   127h and the second force receiving surface 151Le of the separation holding member 151L are arranged at positions where at least parts of them overlap in the W1 and W2 directions.

[0371] The operation of the separation contact mechanism 150L in the image forming apparatus main assembly 170 will be described below. 10 [Mounting of process cartridge to the image forming apparatus main assembly]

[0372] Next, referring to Figures 35 and 36, the engagement between the separation contact mechanism 150R of the process cartridge 100 and the development separation control unit of the image forming apparatus main 15 assembly 170 at the time when the process cartridge 100 is mounted on the image forming apparatus main assembly 170 will be described. For the sake of illustration, these Figures are sectional views in which a portion of the development cover member 128 and a portion of the non-driving side cartridge cover member 117 are partially omitted by the partial sectional line CS, 20 respectively. Figure 35 is a view as seen from the driving side of the process cartridge 100 when the process cartridge is mounted on the cartridge tray 171 (not shown) of the image forming apparatus M and the cartridge tray 171 is inserted into the first mounting position. In this Figure, the parts are omitted except for the process cartridge 100, the cartridge pressing unit 121, and the 25 separation control member 196L.

[0373] As described above, the image forming apparatus main assembly 170 of this embodiment has separation control members 196L corresponding to 2026249127   12 Oct 2026 respective process cartridges 100 as described above. The separation control member 196L is disposed on the lower surface side of the image forming apparatus main assembly 170 with respect to the separation holding member 151L when the process cartridge 100 is placed at the first inner position and the 5 second inner position. The separation control member 196L has a first force applying surface 196La and a second force applying surface 196Lb which project toward the process cartridge and face each other across the space 196Rd. The first force applying surface 196Ra and the second force applying surface 196Rb are connected with each other by a connecting portion 196Rc on the lower 10 surface side of the image forming apparatus main assembly 170. In addition, the separation control member 196R is supported by the control sheet metal 197 rotatably about rotation center 196Re as the center. The separating member 196R is normally urged in the E1 direction by the urging spring. In addition, the control sheet metal 197 is structured to be movable in the W41 and W42 15 directions by a control mechanism (not shown), so that the separation control member 196R is structured to be movable in the W41 and W42 directions.

[0374] As described above, in interrelation with the transition of the front door 11 of the image forming apparatus main assembly 170 from the open state to the closed state, the cartridge pressing unit 121 lowers in the direction of arrow ZA, 20 and the first force applying portion 121a is brought into contact with the pressed surface 152Lf of the pressed surface 152Lf. Thereafter, when the cartridge pressing unit 121 is lowered to a predetermined position which is the second mounting position, the part 152Lh of the force applying member 152L moves to a projecting position where the process cartridge 100 projects downward in the Z2 25 direction (state in Figure 36). When this operation is completed, as shown in Figure 36, a gap T4 is formed between the first force applying surface 196La of the separation control member 196L and the first force receiving surface 152Lp 2026249127   12 Oct 2026 of the force applying member 152L, and a gap T3 is formed between the second force receiving surface 152Lp and the second force applying surface 196Lb. Then, it is placed at the second mounting position where the separation control member 196L does not act on the force applying member 152L. This position 5 of the separation control member 196L is referred to as a home position. At this time, the first force receiving surface 152Lp of the force applying member 152L and the first force applying surface 196La of the separation control member 196L are arranged so as to partially overlap in the W1 and W2 directions. Similarly, the second force receiving surface 152Lp of the force applying member 152L and 10 the second force applying surface 196Lb of the separation control member 196L are arranged so as to partially overlap in the W1 and W2 directions. [Contacting operation of developing unit]

[0375] Next, referring to Figures 36 to 38, the operation of contacting the 15 photosensitive drum 104 and the developing roller with each other by the separation contact mechanism 150L will be described in detail. For the sake of illustration, a part of the development cover member 128, a part of the nondriving side cartridge cover member 117, and a part of the non-driving side bearing 127 are partially omitted in the partial sectional line CS, respectively. It 20 is a sectional view.

[0376] As described above, the development input coupling 32 receives a driving force from the image forming apparatus main assembly 170 in the direction of arrow V2 in Figure 24, so that the developing roller 106 rotates. That is, the developing unit 109 including the developing input coupling 32 25 receives the torque in the arrow V2 direction about the swing axis K from the image forming apparatus main assembly 170. Further, the developing unit 109 also receives an urging force in the arrow V2 direction due to the urging force of 2026249127   12 Oct 2026 the development pressure spring 134 described above.

[0377] As shown in Figure 36, when the developing unit 109 is in the separated position and the separation holding member 151L is in the separated holding position, the developing unit receives this torque and the urging force by 5 the development pressure spring 134. Even in this case, the separation holding surface 151Lc of the separation holding member 151L contacts the contact surface 117c of the non-driving side cartridge cover member 117, and the attitude of the developing unit 109 is maintained at the separation position (state of Figure 36). 10

[0378] The separation control member 196L of this embodiment is structured to be movable from the home position in the direction of arrow W41 in Figure 36. When the separation control member 196L moves in the W41 direction, the second force applying surface 196Lb of the separation control member 196L and the second force receiving surface 152Lp of the force applying member 152L are 15 brought into contact with each other, and the force applying member 152L is rotated in the BD direction about the force applying member swing axis HD. Further, with the rotation of the force applying member 152L, the separation holding member 151L is rotated in the B5 direction, while the second pressing surface 152Lr of the force applying member 152L is in contact with the second 20 pressed surface 151Le of the separation holding member 151L. Then, the separation holding member 151L is rotated by the force applying member 152L to the separation permission position where the separation holding surface 151Lc and the contact surface 117c are separated from each other. Here, the position of the separation control member 196L for moving the separation holding 25 member 151L to the separation permission position shown in Figure 37 is referred to as a first position.

[0379] In this manner, the separation control member 196L moves the 2026249127   12 Oct 2026 separation holding member 151L to the separation permission position. Then, the developing unit 109 rotates in the V2 direction by the torque received from the image forming apparatus main assembly 170 and the urging force of the development pressure spring 134, and moves to the contact position where the 5 developing roller 106 and the photosensitive drum 104 are in contact with each other (state shown in Figure 37). At this time, the separation holding member 151L urged in the direction of arrow B4 by the tension spring 153 is maintained at the separation permission position by the second regulated surface 151Lk contacting the second restriction surface 117d of the non-driving side cartridge 10 cover member 117. Thereafter, the separation control member 196L moves in the direction of W42 and returns to the home position. At this time, the force applying member 152L is rotated in the BC direction by the tension spring 153, and the state changed toward the state in which the first pressing surface 152Lq of the force applying member 152L and the first pressed surface 127h of the non- 15 driving side bearing 127 are in contact with each other (state shown in Figure 38). By this, the above-mentioned gaps T3 and T4 are formed again, and the separation control member 196L is placed at a position where the force applying member 152L does not act. The transition from the state of Figure 37 to the state of Figure 38 is performed without a delay. The position of the separation 20 control member 196L in Figure 38 is the same as that in Figure 36.

[0380] As described above, with the structure of this embodiment, by moving the separation control member 196L from the home position to the first position, the force applying member 152L is rotated to move the separation holding member 151L from the separation holding position to the separation permission 25 position. By this, the developing unit 109 can be moved from the separated position to the contacting position where the developing roller 9 and the photosensitive drum 104 are in contact with each other. 2026249127   12 Oct 2026 [Separating operation of developing unit]

[0381] Next, the operation of moving the developing unit 109 from the contact position to the separation position will be described in detail referring to Figures 5   38 and 39. Note that Figure 39 is a cross-section in which a portion of the development cover member 128, a portion of the non-driving side cartridge cover member 117, and a portion of the non-driving side bearing are partially omitted by the partial cross-section line CS, respectively.

[0382] The separation control member 196L in this embodiment is structured 10 to be movable from the home position in the direction of arrow W42 in Figure 38. When the separation control member 196L moves in the W42 direction, the first force applying surface 196Lb and the first force receiving surface 152Lm of the force applying member 152L come into contact with each other, and the force applying member 152L is rotated in the arrow BC centering about the force 15 applying member swing axis HD. Since the first pressing surface 152Lq of the force applying member 152L is in contact with the first pressed surface 127h of the non-driving side bearing 127, the developing unit 109 is rotated from the contact position in the direction of arrow V1 about the swing axis K (state in Figure 39). Here, the pressed surface 152Lf of the force applying member 152L 20 has an arc shape, and the center of the arc is placed so as to be aligned with the swing axis K. By this, when the developing unit 109 moves from the contact position to the separated position, the force received, from the cartridge pressing unit 121, by the pressed surface 152Lf of the force applying member 152L faces the swing axis K direction. Therefore, the developing unit 109 can be operated 25 so as not to hinder the rotation in the arrow V1 direction. In the separation holding member 151L, the second regulated surface 151Lk of the separation holding member 151L and the second restriction surface 117d of the non-driving 2026249127   12 Oct 2026 side cartridge cover member 117 are separated, and the separation holding member 151L is rotated in the arrow B4 direction by the urging force of the tension spring 153. By this, the separation holding member 151L rotates until the second pressed surface 151Le comes into contact with the second pressing 5 surface 152LR of the force applying member 152L, and by the contact with the second pressing surface 152LR, the position shifts to the separation holding position. When the developing unit is moved from the contact position to the separation position by the separation control member 196L and the separation holding member 151L is placed at the separation holding position, A gap T5 is 10 formed between the separation holding surface 151Lc and the contact surface 117c as shown in Figure 39. Here, the position where the developing unit 109 is rotated from the contact position toward the separation position and the separation holding member 151 can be moved to the separation holding position is referred to as a second position of the separation control member 196L. 15

[0383] Thereafter, the separation control member 196L moves in the direction of the arrow W41 and returns from the second position to the home position. Then, while the separation holding member 151L is maintained at the separation holding position, the developing unit is rotated in the arrow V2 direction by the torque received from the image forming apparatus main assembly 170 and the 20 urging force of the development pressure spring 134, and the separation holding surface 151Lc and the contact surface 117c are brought into contact with each other. That is, the developing unit 109 is in a state where the separation position is maintained by the separation holding member 151L, and the developing roller 106 and the photosensitive drum 104 are in a state where they are separated by a 25 gap P1 (states in Figure 36 and part (a) of Figure 34. By this, the abovementioned gaps T3 and T4 are formed again, and the separation control member 196L is placed at a position where the force applying member 152L does not act 2026249127   12 Oct 2026 (state in Figure 36). The transition from the state of Figure 39 to the state of Figure 36 is executed without a delay.

[0384] As described above, in the structure of this embodiment, by the movement of the separation control member 196L from the home position to the 5 second position, the separation holding member 151L is moved from the separation permission position to the separation holding position. And, by the returning of the separation control member 196L from the second position to the home position, the developing unit 109 becomes in the state of maintaining the separation position by the separation holding member 151L. 10

[0385] So far, the operation of the separation mechanism placed on the driving side of the process cartridge 100 and the operation of the separation mechanism placed on the non-driving side have been described separately, but in this embodiment, they operate in interrelation with each other. That is, when the developing unit 109 is positioned at the separation position by the separation 15 holding member R, the developing unit 109 is positioned at the separation position by the separation holding member L at substantially the same time, and the same applies to the contact position. Specifically, the movements of the separation control member 121R and the separation control member 121L described in Figures 23 to 27 and 35 to 39 are integrally carried out by a 20 connecting mechanism (not shown). By this, the timing at which the separation holding member 151R provided on the driving side is placed at the separation holding position, and the timing at which the separation holding member 151L provided on the non-driving side is placed at the separation holding position are substantially the same, and the timing at which the separation holding member 25   151R is placed at the separation permission position, and the timing at which the separation holding member 151L is placed at the separation permission position, and the timing at which the separation holding member 151L is placed at the 2026249127   12 Oct 2026 separation permission position are substantially the same. These timings may be different between the driving side and the non-driving side, but in order to shorten the time from the start of the print job by the user until the printed matter is discharged It is desirable that at least the timings of positioning at least the 5 separation permission positions are the same. In this embodiment, the separation holding member swing axes H of the separation holding member 151R and the separation holding member 151L are common, but it is sufficient that the timings of the separation holding member 151L and the separation holding member 151L are substantially the same as described above, and therefore the 10 above-described example is not restrictive. Similarly, the force applying member swinging axis HC of the force applying member 152R and the force applying member swinging axis HE of the force applying member 152L are axes that do not match, but it will suffice if the timings of being placed at the separation permission positions are substantially the same as described above, 15 and therefore, the above-described example is not restrictive.

[0386] As described above, the driving side and the non-driving side are provided with the same separation contact mechanisms, respectively, and they operate substantially at the same time. By this, even when the process cartridge 100 is twisted or deformed in the longitudinal direction, the amount of separation 20 between the photosensitive drum 104 and the developing roller 9 can be controlled at the respective end portions in the longitudinal direction. Therefore, it is possible to suppress variations in the amount of separation in the longitudinal direction.

[0387] Further, according to this embodiment, by moving the separation 25 control member 196R (L) between the home position, the first position, and the second position in one direction (arrows W41 and W42 directions), it is possible to control the contact state and the separation state between the developing roller 2026249127   12 Oct 2026 106 and the photosensitive member. Therefore, it is possible that the developing roller 106 is brought into contact with the photosensitive drum 104 only when the image is formed, and the developing roller 4 is maintained in a state of being separated from the photosensitive drum 104 when the image is not formed. 5 Therefore, even if the image formation is not carried out for a long term, the developing roller 106 and the photosensitive drum 104 are not deformed, and a stable image can be formed.

[0388] Further, according to this embodiment, the force applying member 152R (L) acting on the separation holding member 151R (L) to rotate and move 10 can be positioned at the accommodation position by the urging force of the tension spring 153 or the like. Therefore, it does not project out of the outermost shape of the process cartridge 100, when the process cartridge 100 is outside the image forming apparatus main assembly 170, and the process cartridge 100 per se can be downsized. 15

[0389] Similarly, the force applying member 152R (L) can be positioned at the accommodation position by the urging force of the tension spring 153 or the like. Therefore, when the process cartridge 100 is to be mounted to the image forming apparatus main assembly 170, the mounting of the process cartridge 100 can be completed by moving only in one direction. For this reason, it is not necessary 20 to move the process cartridge 100 (tray 171) in the vertical direction. Accordingly, the image forming apparatus main assembly 170 does not require an additional space, and the main assembly can be downsized.

[0390] Further, according to this embodiment, when the separation control member 196R (L) is placed at the home position, the separation control member 25   196R (L) is not loaded from the process cartridge 100. Therefore, the rigidity required for the mechanism for operating the separation control member 196R (L) and the separation control member 196R (L) can be reduced, and the size can 2026249127   12 Oct 2026 be reduced. Further, since the load on the sliding portion of the mechanism for operating the separation control member 196R (L) is also reduced, wear of the sliding portion and production of abnormal noise can be suppressed.

[0391] Further, according to this embodiment, the developing unit 109 can 5 maintain the separated position only by the separation holding member 151R (L) included in the process cartridge 100. Therefore, the component tolerance can be eased and the spacing amount can be minimized by reducing the number of parts resulting in variations in the spacing amount between the developing roller 106 and the photosensitive drum 104. Since the amount of spacing can be 10 reduced, when the process cartridge 100 is arranged in the image forming apparatus main assembly 170, the area occupied by the developing unit 109 when the developing unit 109 moves to the contact position and to the separated position can be made smaller, so that the image forming apparatus can be downsized. In addition, the space for the developer accommodating portion 29 15 of the developing unit 109 which moves to the contact position and to the separation position can be increased, and therefore, the downsized and large-capacity process cartridge 100 can be placed in the image forming apparatus main assembly 170.

[0392] Further, according to this embodiment, the force applying member 20   152R (L) can also be positioned at the accommodation position when the process cartridge 100 is mounted, and the developing unit 109 Can maintain the separation position only by the separation holding member 151R (L) of the process cartridge 100. Therefore, when the process cartridge 100 is mounted to the image forming apparatus main assembly 170, the process cartridge 100 can be 25 mounted by moving only in one direction. For this reason, it is not necessary to move the process cartridge 100 (tray 171) in the vertical direction. Accordingly, the image forming apparatus main assembly 170 does not require a space, and the 2026249127   12 Oct 2026 main assembly can be downsized. Further, since the separation amount can be reduced, when the process cartridge 100 is placed in the image forming apparatus main assembly 170, the area occupied by the developing unit 109 when the developing unit 109 moves to the contact position and to the separation position 5 can be made small, and therefore, the image forming apparatus can be downsized. In addition, since the space for the developer accommodating portion 29 of the developing unit 109 which moves to the contact position and to the separation position can be increased, the downsized and large-capacity process cartridge 100 can be placed in the image forming apparatus main assembly 170. 10 [Details of arrangement of separation contact mechanism]

[0393] Subsequently referring to Figures 40 and 41, the arrangement of the separation contact mechanisms R and L in this embodiment will be described in detail. 15

[0394] Figure 40 is an enlarged view of the periphery of the separation holding member 151R as the process cartridge 100 is viewed from the driving side along the swing axis K (photosensitive drum axis direction) of the developing unit 109. In addition, for the sake of illustration, it is a sectional view in which a portion of the development cover member and a portion of the 20 driving side cartridge cover member 116 are partially omitted by the partial sectional line CS. Figure 41 is an enlarged view of the periphery of the separation holding member 151R as the process cartridge 100 is viewed from the non-driving side along the swing axis K of the developing unit 109 (along the axis in the photosensitive drum axis direction). In addition, for the sake of 25 illustration, it is a sectional view in which a portion of the development cover member 128 and a portion of the driving side cartridge cover member 116 are partially omitted by the partial sectional line CS. Regarding the arrangement of 2026249127   12 Oct 2026 the separation holding member and the force applying member described below, there is no distinction between the driving side and the non-driving side except for the part which will be described in detail hereinafter, and they are common, and therefore, the description will be made only for the driving side, the same 5 applies to the non-driving side.

[0395] As shown in Figure 40, the rotation center of the photosensitive drum 104 is a point M1, the rotation center of the developing roller 106 is a point M2, and the line passing through the points M1 and M2 is a line N. In addition, the contact region between the separation holding surface 151Rc of the separation 10 holding member 151R and the contact surface 116c of the driving side cartridge cover member 116 is M3, and the contact region between the second pressed surface 151Re of the separation holding member 151R and the second pressing surface 152Rr of the second force applying member 152R is M4. Further, the distance between the swing axis K and the point M2 of the developing unit 109 is 15 a distance e1, the distance between the swing axis K and the region M3 is e2, and the distance between the swing axis K and the point M4 is e3.

[0396] In the structure of this embodiment, the following positional is a relationship when the developing unit 109 is in the separated position and the force applying member 152R (L) is in the projecting position. As viewed along 20 the axial direction of the swing axis K shown in Figure 40 (the axial direction of the photosensitive drum), at least a part of the contact region M3 between the separation holding member 151R and the driving side cartridge cover member is placed on a side opposite from the side in which the development coupling 32 center (swing axis K) exists, with respect to the line N passing through the center 25 of the photosensitive drum 104 and the center of the developing roller. That is, the separation holding surface 151Rc of the separation holding member 151R is arranged such that the distance e2 is longer than the distance e1. 2026249127   12 Oct 2026

[0397] By arranging the separation holding member 151R and the separation holding surface 151Rc in this manner, it is possible to suppress variations in the attitude of the spaced position of the developing unit 109 when the positions of the separation holding surface 151Rc vary due to component tolerances and the 5 like. That is, the influence of the variation of the separation holding surface 151Rc on the separation amount (gap) P1 (see part (a) of Figure 42) between the developing roller 106 and the photosensitive drum 104 can be minimized, and the developing roller 106 can be accurately spaced from the photosensitive member 104. Further, it is not necessary to provide an additional space for permitting 10 retraction when the developing unit 109 is separated, which leads to the downsizing of the image forming apparatus main assembly 170.

[0398] Further, the first force receiving portion 152Rk (Lk) and the second force receiving portion 152Rn (Ln), which are the force receiving portions of the force applying member 152R (L), are placed on a side opposite from the rotation 15 centers of the development coupling 32 with respect to the extension line of the line N.

[0399] As described above, the force receiving portions 152Rk (Lk) and 152Rn (Ln) are provided at the end portions in the longitudinal direction. Further, as shown in Figure 15 (Figure 16), a cylindrical portion 128b (127a), 20 which is a support portion of the developing unit 109, is provided at the end portion in the longitudinal direction. Therefore, by disposing the force receiving portions 152Rk (Lk) and 152Rn (Ln) at positions opposite from the cylindrical portion 128b (127a) (that is, the swing axis K) of the developing unit 109 with respect to the line N the functional elements can be arranged efficiently. That is, 25 it leads to downsizing of the process cartridge 100 and the image forming apparatus M.

[0400] In addition, the force receiving portions 152Rk and 152Rn are placed 2026249127   12 Oct 2026 at the longitudinal driving side end portions. Further, as shown in Figure 15, a development drive input gear 132 that receives a drive from the image forming apparatus main assembly 170 and drives the developing roller 106 is provided at the end portion on the driving side in the longitudinal direction. As shown in 5 Figure 40, the force applying members 152Rk and 152Rn are placed on the side opposite from the rotation center K of the development drive input gear 132 (development coupling portion 132a) shown by the broken lines with respect to the extension line of the line N. With this arrangement, the functional elements can be efficiently arranged. That is, it leads to downsizing of the process 10 cartridge 100 and the image forming apparatus M.

[0401] Further, the contact portion between the separation holding member 151R and the force applying member 152R is arranged such that the distance e3 is longer than the distance e1. By this, the separation holding member 151R and the driving side cartridge cover member 116 can be brought into contact with 15 each other with a lighter force. That is, the developing roller 106 and the photosensitive drum 104 can be stably separated from each other. [Detailed description of drive transmission mechanism for photosensitive drum]

[0402] A structure for transmitting a driving force from the image forming 20 apparatus main assembly to the drum unit 103 of the cartridge 100 (see part (a) of Figure 1 to drive (rotate) the drum unit will be described.

[0403] The drum unit 103 shown in Figures 1, 13 and 55 to 58 is a unit including a photosensitive drum, a drum coupling (cartridge side coupling, coupling member) 143, and a drum flange 142 (see Figure 13). The drum unit 25   103 is mountable to and dismountable from the image forming apparatus main assembly as a part of the cartridge 100. By mounting the drum unit 103 to the main assembly of the apparatus, it can be connected with a drive transmission 2026249127   12 Oct 2026 unit 203 (see Figures 43 and 44, details will be described hereinafter) of the main assembly of the apparatus. The drum unit rotates in the direction of arrow A during image formation (see Figures 1, 55 to 57). In this embodiment, as the driving side of the drum unit 103 (the side where the drum coupling 143 is 5 located) is viewed, that is, when the drum unit 103 is viewed along the arrow M1B direction, the rotational direction of the drum unit 103 corresponds to the clockwise direction (See Figure 1). In other words, when the front surface of the drum coupling 143 is viewed, the rotational direction A of the drum coupling 143 corresponds to the clockwise direction. 10

[0404] The rotational direction A of the drum unit (drum coupling 143 and the photosensitive drum 104) will be described below using the movement of the surface of the photosensitive drum 104 (see Figures 2 and 3). In Figures 2 and 3, unlike Figure 1, the cartridge is viewed from the non-driving side, and therefore, the rotational direction A of the drum unit 103 is counterclockwise. 15

[0405] As shown in Figure 3, the surface of the photosensitive drum 104 is charged inside the cartridge at a position near the charging roller 105 (around the position where it contacts the charging roller). Thereafter, the surface of the photosensitive drum 104 moves to a position where it receives the laser beam U, by which an electrostatic latent image is formed on the surface. Then, the 20 surface of the photosensitive drum 104 moves to a position near the developing roller 106 (a position in contact with the developing roller in this embodiment), and a latent image formed on the surface of the photosensitive drum 104 developed into a toner image. After that, the surface of the photosensitive drum moves to a position exposed below the cartridge and outside the casing of the 25 cartridge. Then, as shown in Figure 2, the surface of the photosensitive drum 104 exposed from the casing of the cartridge contacts the intermediary transfer belt 12a provided in the image forming apparatus main assembly. By this, the 2026249127   12 Oct 2026 toner image is transferred from the surface of the photosensitive drum 104 to the transfer belt 12a. Thereafter, the surface of the photosensitive drum 104 returns, inside of the cartridge, to a position near the charging roller 105.

[0406] In summary, when the photosensitive drum 104 rotates due to the 5 driving force of the coupling 143, a part of the surface of the photosensitive drum 104 moves from a position close to the charging roller 105 to a position close to the developing roller 106. Thereafter, the part of the surface of the photosensitive drum 104 is exposed to the outside of the casing of the cartridge, and then returns to the inside of the casing of the cartridge and approaches the 10 charging roller 105 again.

[0407] As described above, the cartridge 100 of this embodiment does not have a cleaning means for contacting the photosensitive drum 104 and removing the toner on the surface of the photosensitive drum 104 (see Figure 3). Therefore, the torque required to rotate the drum unit 103 (photosensitive drum 15    104) inside the cartridge 100 is relatively small. In the case of such a structure, the drum unit 103 is easily affected by the surroundings when it is driven, and as a result, the drum unit 103 may be externally affected by the outside with the result of unstable rotation speed. For example, in this embodiment, the developing roller 106, the charging roller 105, and the transfer belt 12a are in 20 contact with the photosensitive drum 104. If the magnitude of the frictional force generated between these means and the photosensitive drum 104 fluctuates, the speed of the drum unit 103 may fluctuate.

[0408] Therefore, in this embodiment, the structure is such that a torque a predetermined level or higher is required, when the drum drive coupling 180 of 25 the drive transmission unit 203 (see Figure 43) provided in the main assembly of the apparatus rotates the drum unit (photosensitive drum 104) of the cartridge. By this, the rotation of the drum unit 103 is relatively less influenced by the 2026249127   12 Oct 2026 external factors, and its rotation speed is stable.

[0409] First, referring to part (a) of Figure 1, the drum coupling 143 of the process cartridge 100 will be described. Part (a) of Figure 1 is a perspective view of the drum coupling. 5

[0410] The drum coupling 143 of this embodiment is manufactured by injection molding a polyacetal resin. As the material, a resin material such as a polycarbonate resin or polybutylene terephthalate resin, or a resin material provided by blending these with glass fiber, carbon fiber or the like may be used. Alternatively, a processing method such as die casting or cutting may be used 10 with a metal material such as aluminum, iron, or stainless steel.

[0411] Next, referring to Figures 1, 55 to 58, the shape of the drum coupling 143 will be described.

[0412] In the following description of the drum coupling 143, the direction (direction of arrow M1A) from the photosensitive drum 104 toward the drive 15 transmission unit 230 (drum drive coupling 180) along the axial direction is called outward (outward) in the axial direction. In addition, the direction opposite to the outward direction (the direction of the arrow M1B) is called inward direction in the axial direction.

[0413] In other words, in the drum coupling, the outward direction (M1A 20 direction) in the axial direction is the direction from the non-driving side end portion 104b of the photosensitive drum toward the driving side end portion 104a (leftward in Figure 80). Alternatively, the outward direction (M1A direction) in the axial direction is the direction from the non-driving side cartridge cover 117 of the cartridge 100 toward the driving side cartridge cover 116 in Figure 14. 25

[0414] The inward direction in the axial direction (M1B direction) is the direction from the driving side end portion 104a of the photosensitive drum 104 toward the non-driving side end portion 104b (rightward in Figure 80). 2026249127   12 Oct 2026 Alternatively, the inward direction (M1B direction) in the axial direction is the direction from the driving side cartridge cover 116 of the cartridge 100 toward the non-driving side cartridge cover 117 in Figure .

[0415] As shown in part (b) of Figure 1, the drum coupling 143 is mounted to 5 one longitudinal end (driving side end) of the photosensitive drum 104. As described above, the shaft portion 143j shown in Figure 1 is rotatably supported by the driving side cartridge cover member 116 (see Figure 15) which supports the photosensitive drum unit 103. The drum unit 103 is structured to be rotatable in a predetermined rotational direction (direction of arrow A) during the 10 image forming operation in which the latent image on the surface of the photosensitive drum is developed.

[0416] The drum coupling 143 receives a driving force for rotating the photosensitive drum 104 from the main assembly drive transmission unit 203 of the main assembly of the apparatus, and also receives a braking force for 15 applying a load against the rotation of the photosensitive drum 104, as well.

[0417] The drum coupling 143 is provided with a projections projecting outward in the axial direction from the surface of the end portion of the shaft portion 143j (see Figures 1, 52 to 57). This projection has a driving force receiving portion 143b as a first side surface (first side portion) for receiving the 20 driving force from the driving transmission unit 203. Further, the projection of the drum coupling 143 includes a braking force receiving portion 143c as a second side surface (second side portion) for receiving the braking force from the drive transmission unit 203.

[0418] The driving force receiving portion 143b is a side surface (side portion) 25 facing the upstream side in the rotational direction A of the drum unit. Further, the braking force receiving portion 143c is a side surface (side portion) facing the downstream side in the rotational direction A. 2026249127   12 Oct 2026

[0419] In other words, one of the driving force receiving portion 143b and the braking force receiving portion 143c faces one side in the circumferential direction of the drum unit, and the other faces the other side in the circumferential direction. That is, the driving force receiving portion 143b and the braking 5 force receiving portion 143c are side surfaces (side portions) facing opposite to each other in the rotational direction and the circumferential direction.

[0420] Further, the projection of the drum coupling 143 has a helical slope (inclined portion, slope) 143d as a top surface (upper surface, upper portion, upper portion). The slope (top surface) 143d is a portion facing outward (arrow 10 MA1 direction) in the axial direction. That is, the slope 143d is a portion facing toward the side opposite to the non-driving side end portion of the drum unit (that is, the end portion on the side where the drum flange 142 (Figure 13) is arranged). In other words, the helical slope (top surface) 143d of the coupling 143 is a portion facing the side opposite to the side on which the photosensitive drum 104 15 exist.

[0421] The helical slope 143d is inclined so as to be outward in the axial direction (arrow MA1 direction) toward the upstream side in the rotational direction (upstream side in the arrow A direction). That is, the slope 143d goes away from the non-driving side of the drum unit 103 as goes toward the upstream 20 side in the rotational direction. In other words, the slope 143d is inclined so as to go away from the photosensitive drum as goes toward the upstream side in the rotational direction.

[0422] In other words, the helical slope 143d extends toward the non-driving end of the drum unit and the cartridge from upstream to downstream in the 25 rotational direction. Namely, when the distance of the helical slope 143d from the non-driving end of the cartridge is measured along the axial direction, the distance becomes shorter toward the downstream in the rotational direction. 2026249127   12 Oct 2026

[0423] The helical slope 143d includes a downstream portion (downstream top surface, downstream inclined slope, downstream inclined portion, downstream guide) 143d1 sandwiched between the driving force receiving portion 143b and the braking force receiving portion 143c in the rotational direction of the drum 5 unit. Further, the slope 143d has an upstream portion (upstream side top surface, upstream side slope, upstream side inclined portion, upstream guide) 143d2. The upstream portion 143d2 of the helical slope 143d is provided upstream of the driving force receiving portion 143b and the downstream portion 143d1 of the helical slope 143d in the rotational direction (see Figures 55 to 58). 10

[0424] Further, as the length of the slope 143d is measured along the rotational direction of the drum unit, the length of the upstream side slope 143d2 is larger than the length of the downstream side slope 143d1.

[0425] The upstream side portion (upstream side slope) 143d2 of the slope 143d is provided inside (the side closer to the axis L) of the driving force 15 receiving portion 143b in the radial direction. That is, the upstream side portion (upstream side top surface, upstream side slope) 143d2 of the slope 143d is provided closer to the axis L (part (a) of Figure 1 than the driving force receiving portion 143b. The axis L (part (a) of Figure 1) is the axis (rotation axis) which is the center of rotation of the coupling 143 and the photosensitive drum 104. 20

[0426] Further, the projection of the drum coupling 143 is provided with a circular hole portion 143a as an opening for engaging with the positioning boss (positioning portion) 180i of the drum drive coupling 180 and positioning each other's axes. The circular hole portion 143a has a circular opening having a cross-section perpendicular to the axis L of the drum coupling 143, and is 25 extended along the axis L.

[0427] The projection of the drum coupling 143 includes a shaft portion 143p (see Figure 1) formed along the axis L (see part (a) of Figure 1, and the circular 2026249127   12 Oct 2026 hole portion 143a is formed inside the shaft portion 143p. The shaft portion 143p is a portion for forming the circular hole portion 143a.

[0428] The shaft portion 143p and the circular hole portion 143a are extended aligned with the axis L. By forming the circular hole portion 143a, the space 5 from the rotation axis L of the drum unit (see part (a) of Figure 1 to the inner surface of the drum coupling 143 is an open space. The shaft portion 143p has a diameter smaller than the shaft portion 143j described above.

[0429] The drum coupling 143 described above has an axisymmetric shape (axisymmetric shape) with respect to the axis L (see part (a) of Figure 1. The 10 driving force receiving portion 143b, the braking force receiving portion 143c, and the helical slope 143d are arranged at two locations so as to be separated by 180 ° in the circumferential direction, respectively, thus providing a first coupling portion 143r and a second coupling portion 143s (see Figure 58).

[0430] Each coupling portion includes one driving force receiving portion 15   143b, one braking force receiving portion 143c, and one helical slope 143d, and the first coupling portion 143r and the second coupling portion 143s are placed in position symmetrical with respect to the axis.

[0431] The driving force receiving portion 143b, the braking force receiving portion 143c, and the helical slope 143d are arranged around the above- 20 mentioned circular hole portion 143a and the shaft portion 143p. The driving force receiving portion 143b, the braking force receiving portion 143c, and the helical slope 143d are located more remote than the circular hole portion 143a and the shaft portion 143p from the axis L of the drum unit.

[0432] Next, referring to Figures 43, 44, and 59, the structure of the main 25 assembly side drive transmission unit 203 provided on the main assembly side of the apparatus will be described. The drive transmission unit 203 is a unit for rotationally driving the drum coupling 143 by connecting (engaging) with the 2026249127   12 Oct 2026 drum coupling 143.

[0433] Figure 43 is an exploded perspective view of the main assembly side drive transmission unit 203. Figure 59 is an enlarged perspective view of a portion shown in Figure 43. Figure 44 is a sectional view of the main assembly 5 side drive transmission unit 203.

[0434] A drive gear 201 is rotatably supported by a support shaft 202 fixed to a frame (not shown) of the apparatus main assembly 170, and a driving force is transmitted from a motor (not shown) to rotate the drive gear 201. The drum drive coupling 180 includes a cylindrical portion 180c and a flange portion 180a 10 provided at the end thereof, and the flange is fitted and supported by a fitting portion 201a of the drive gear 201. Further, the drum drive coupling 180 is provided with a rotation stop portion 180b projecting from the flange portion 180a, which receives a driving force when rotating in contact with the rotation stop portion 201b of the drive gear 201. The drive transmission unit 203 15 includes a plurality of components inside the cylindrical portion 180c of the drum drive coupling 180.

[0435] The parts arranged inside the cylindrical portion 180c are as follows. There are a brake members 206 which is supported and stopped by the support shaft 202, a brake transmission member 207 which is connected with the brake 20 member 206 to transmit the braking force, and first and second braking engagement members 204 and 208 engaged with the braking force receiving surface 143c of the drum coupling 143, and, a brake engagement spring 211 and a drum drive coupling spring 210 which are arranged along the axis M1 and which generate an urging force in the direction of the axis M1 (axis direction). The 25 axis M1 is a rotation axis of the main assembly side drive transmission unit 203.

[0436] The shape of each of the parts arranged inside the main assembly drive transmission unit 203 will be described. 2026249127   12 Oct 2026

[0437] The first braking engagement member 204 comprises a cylindrical portion 204d, a flange portion 204a, and a coupling engaging portion 204b which projects like a claw and engages with the drum coupling 143. A part of the cylindrical portion includes a rotation stop recess 204c which engages with the 5 rotation stop projection 208c of the second braking engagement member 208, which will be described hereinafter.

[0438] The second braking engagement member 208 includes a flange portion 208a, a coupling engaging portion 208b projecting in the form of a claw and engaging with the drum coupling 143, and the rotation stop projection 208c 10 engaged with the rotation stop recess 204c of the first braking engagement member 204. Since the second braking engagement member 208 is stopped from rotating relative to the first braking engagement member 204, the first and second braking engagement members 204 and 208 rotate integrally with each other. Further, the first and second braking engagement members 204 and 208 15 are connected so as to move integrally also in the axial direction.

[0439] Therefore, the first and second braking engagement members 204 and 208 may be collectively referred to simply as braking engagement members (204, 208).

[0440] The first braking engagement member 204 is an outer braking 20 engagement member disposed on the outer side in the radial direction, and the second braking engagement member 208 is an inner braking engagement member disposed on the inner side in the radial direction.

[0441] The brake transmission member 207 includes a flange portion 207a and a shaft portion 207b. The flange portion 207a is provided with a projection 25   207e which engages with the projection 204e provided on the flange portion 204a of the first braking engagement member 204. The flange portion 207a of the brake transmission member 207 is disposed between the flange portion 204a of 2026249127   12 Oct 2026 the first braking engagement member 204 and the flange portion 208a of the second braking engagement member 208, with a play (gap) G therebetween in the axial direction (Fig. 44). In the axial direction M1A, when the brake transmission member 207 is in a position relative to the first brake engagement 5 member 204 in which the projection 207e of the brake transmission member 207(see Figures 43 and 59) is engaged with the projection 204e of the first brake engagement member 204, the first brake transmission member and the first and second braking engagement members 204 and 208 rotate integrally. On the other hand, when the brake transmission member 207 is in a position relative to 10 the first braking engagement member 204 in the axial direction in which the projection 207e does not engage with the projection 204e, the brake transmission member 207 does not limit the rotation of the first and second engagement members 204, 208. That is, the first and second braking engagement members 204 and 208 are rotatable relative to the brake transmission member 207. The 15 shaft portion 207b has a non-circular cross-section, and engages with the engagement hole 206c of the brake member 206 which will be described hereinafter so that the brake transmission member 207 and the brake member 206 are integrally rotated.

[0442] The brake member 206 is divided into two portions, namely, a fixed 20 side 206a and a rotating side 206b, but they are integrated in the axial direction by a retainer (not shown). The fixed side 206a is supported by the support shaft 202, and the rotation about the shaft is also fixed. On the other hand, the rotating side 206b can rotate around the support shaft 202, but rotates while receiving a braking force (load) in the rotational direction from the fixed side 25   206a. The method of producing the braking force can be appropriately selected from those using friction and viscosity.

[0443] The braking engagement members (204, 208) are connected to the 2026249127   12 Oct 2026 brake member 206 by way of the brake transmission member 207 as described above. Therefore, the rotational torque of the braking engagement members (204, 208) increases due to the influence of the load (braking force) generated by the brake member 206. The brake engagement spring 211 is a compression coil 5 spring, and is provided so as to be sandwiched and compressed between the end surface 206d of the brake member 206 and the flange portion 204a of the first braking engagement member 204. As a result, the spring 211 applies a repulsive force (urging force, elastic force) to each of the end surface 206d of the brake member 206 and the flange portion 204a of the first braking engagement 10 member 204.

[0444] The drum drive coupling spring 210 is a compression coil spring, and is provided so as to be sandwiched and compressed between the end surface 206d of the brake member 206 and the flange portion 207a of the brake transmission member 207. As a result, the spring 210 applies a repulsive force (urging force, 15 elastic force) to each of the end surface 206d of the brake member 206 and the flange portion 207a of the brake transmission member 207.

[0445] The brake transmission member 207 directly receives the repulsive force of the drum drive coupling spring 210 while receiving the repulsive force of the brake engagement spring 211 by way of the flange portion 204a of the first 20 braking engagement member 204. The projection 207f at the end of the brake transmission member 207 in the axial direction M1A abuts against the contact surface 180f of the drum drive coupling 180 (see Figure 44).

[0446] By this, the drum drive coupling 180 also receives the force of the drum drive coupling spring 210 and the brake engagement spring 211 by way of 25 the brake transmission member 207. The drum drive coupling 180 tends to move due to the force of the springs 210 and 211. Therefore, the movement of the drum drive coupling 180 in the arrow M1B direction is regulated (restricted) 2026249127   12 Oct 2026 by the axial direction restricting portion 212 (see Figure 44) so that the drum drive coupling 180 does not drop off the main assembly side drive transmission unit 203. Specifically, when the drum drive coupling 180 moves to the arrow M1B by a certain distance, the flange portion 180a (see Figure 43) of the drum 5 drive coupling 180 comes into contact with the restriction portion 212 (see Figure 44). By this, the movement and drop-off of the drum drive coupling 180 can be suppressed.

[0447] When the drum drive coupling 180 receives a force in the arrow M1A direction from the outside in this state, the drum drive coupling 180 can move in 10 the arrow M1A direction while compressing the springs 210 and 211.

[0448] Further, when the braking engagement members (204, 208) engage with the coupling 143, the coupling engaging portions 204b, 208b may interfere with the coupling 143 (see Figure 60, details will be described hereinafter). In such a case, the braking engagement members (204, 208) can enter (retract) into 15 the depth of the drive transmission unit 203 while compressing the springs 210 and 211 in the direction of the arrow M1A (see Figure 61).

[0449] The braking engagement members (204, 208) are disposed with a gap G from the brake transmission member 207 as described above (see Figure 44). Within a range of the width of the gap G, the braking engagement members (204, 20   208) can move and retract in the M1A direction relative to the brake transmission member 207. Similarly, the braking engagement members (204, 208) can move in the direction of the arrow M1A within the range of the width of the gap G relative to the drum drive coupling 180. When the braking engagement member (204, 208) moves in the direction of the arrow M1A relative to the brake 25 transmitting member 207 and the drum drive coupling 180, the brake engagement spring 211 is compressed.

[0450] The brake transmitting member 207 is also moved in the direction of 2026249127   12 Oct 2026 arrow M1A together with the braking engagement member (204, 208), by the braking engagement member (204, 208) contacting the brake transmitting member 207 which tends to move in the direction of the arrow M1A beyond the width of the gap G. 5

[0451] Together with the braking engagement members (204, 208), the drum drive coupling 180 also moves in the direction of arrow M1A. As shown in Figure 62, the drum drive coupling 180 and the first braking engagement member 204 are provided with a projecting engaging portion 180u and an engaging portion 204u, respectively. Therefore, when the braking engagement member 10   204 moves in the direction of the arrow M1A relative to the drum drive coupling 180 for a predetermined distance or more, the engaging portion 204u pushes the engaging portion 180u to retract the drive coupling 180 in the M1A direction. At this time, not only the spring 211 but also the spring 210 is compressed.

[0452] When the braking engagement member (204, 208) moves in the 15 direction of the arrow M1A relative to the brake transmission member 207, the projection 207e of the brake transmission member 207 and the projection 204e of the first braking engagement member are disengaged. That is, the braking engagement members (204, 208) are disconnected from the brake transmission member 207, and the braking force is not transmitted from the brake transmission 20 member 207. The brake members (204, 208) can rotate relative to the brake transmission member 207 without receiving the rotational load produced by the brake member 206.

[0453] That is, by retracting the braking engagement members (204, 208) in the direction of arrow M1A, the braking engagement members are movable from 25 the position in which the brake member 206 receives the rotational load (braking force) during rotation to the position in which the rotational load is not received during rotation. The braking engagement members (204, 208) are structured to 2026249127   12 Oct 2026 reduce the own required torque by moving in the M1A direction relative to the brake transmission member 207 and to the drum drive coupling 180.

[0454] Figure 45 is a perspective view illustrating the positional relationship between the drum drive coupling 180 and the braking engagement members (204, 5   208). Part (a) of Figure 45 is a perspective view of only the drum drive coupling 180, and part (b) of Figure 45 shows a perspective view in which both the drum drive coupling 180 and the braking engagement member (204, 208) are included. Parts (c) and (d) of Figure 45 are illustrations in which the reinforcing cylindrical portion 180e of the drum drive coupling 180 is not shown (invisible) 10 for the sake of better illustration. The phases of the braking engagement members (204, 208) differ between parts (c) and (d) of Figure 45.

[0455] As shown in part (a) of Figure 45, the drum drive coupling (driving force applying member) 180 includes a driving transmission surface 180d provided at each of two positions which are away from each other by 180 degrees 15 in the circumferential direction as a surface (driving force applying portion) which engages with the coupling 143 to transmit the driving force. The drum drive coupling has an axisymmetric shape.

[0456] A through hole 180f communicating in the direction of the axis M1 is provided in a portion other than the drive transmission surface 180d. Through 20 the through hole 180f, the coupling engaging portions 204b and 208b of the first braking engagement member 204 and the second braking engagement member 208 are exposed in the direction facing the coupling 143 (see Figure 60).

[0457] Part (b) of Figure 45 shows a state in which the coupling engaging portions 204b and 208b of the first braking engagement member 204 and the 25 second braking engagement member 208 are exposed. The drum drive coupling 180 is provided with a reinforcing cylindrical portion 180e in order to increase the rigidity of the drive transmission surface 180d. Part (c) of Figure 45 is an 2026249127   12 Oct 2026 illustration in which the reinforcing cylindrical portion 180e is not shown for the sake of better illustration. Part (c) of Figure 45 shows a state in which the coupling engaging portions 204b and 208b and the drive transmission surface 180d are in a close phase relationship in the rotational direction A. The size of 5 the through hole 180f is selected to be wider than the widths of the coupling engaging portions 204b and 208b in the circumferential direction. Therefore, the coupling engaging portions 204b and 208b can move within a predetermined range in the rotational direction in the drum drive coupling 180.

[0458] Part (d) of Figure 45 shows a state in which the coupling engaging 10 portions 204b and 208b and the drive transmission surface 180d are in a distant phase relationship in the rotational direction A.

[0459] Next, referring to Figures 1 and 43 to 51, a method of connecting the main assembly side drive transmission unit 203 of the drive transmission mechanism and the photosensitive member coupling 143 on the process cartridge 15    100 side will be described. [Coupling engagement operation]

[0460] Next, the process of coupling between the main assembly side drum drive coupling 180 of the image forming apparatus main assembly 170 and the 20 drum coupling 143 of the process cartridge 100 will be described.

[0461] Figure 46 shows a sectional view of the image forming apparatus main assembly 170 around the main assembly side drum drive coupling 180. Referring to Figure 46, the outline of the movement of the drum drive coupling 180 on the main assembly side will be described. 25

[0462] When the user opens the front door 111 (Figure 4) of the image forming apparatus main assembly to replace the process cartridge 100, the drive transmission unit 203 is moved in the direction of the arrow M1A along the axis 2026249127   12 Oct 2026 M1 by a link mechanism (not shown) connected to the front door 111. That is, the drive transmission unit 203 is in a state of being moved away from the process cartridge 100 and the drum coupling 143 (see Figure 60).

[0463] When the user mounts the process cartridge 100 and closes the front 5 door 111, the action of the link described above disappears. Therefore, the drum drive coupling 180, the brake engagement members 204, 208, and the brake transmission member 207 tends to move again in the direction of arrow M1B by the urging forces of the drum drive coupling spring and the brake engagement spring 211. At this time, the drum coupling 143 of the process cartridge 100 10 stands by in the direction of the arrow M1B and interferes with the approaching drive transmission unit 203 (states shown in Figures 61, 65, and 69). The drum coupling 143 and the drive transmission unit 203 are pressed against each other.

[0464] In these states, the drum coupling 143 and the drum drive coupling 180 of the drive transmission unit 203 are normally not engaged. 15

[0465] In order for the drum coupling 143 and the main assembly side drum drive coupling 180 to be in a normal engaged state, the drive transmission unit 203 is required to be further rotated from the above-mentioned pressing state. That is, it is necessary to advance the drive process of the drive transmission unit 203 until the drum drive coupling 180 on the main assembly side engages with 20 the drum coupling 143.

[0466] Further, the process until the engagement is completed may be carried out in different patterns, and therefore, the description will be made, dividing into a plurality of cases depending on the phase of the drum coupling 143 and the main assembly side drum drive coupling 180. 25

[0467] Part (a) of Figure 47 shows the drum coupling 143, and part (b) of Figure 47 shows the drive transmission unit, both as viewed in the axial direction.

[0468] Referring to part (a) of Figure 47, the shape of the coupling 143 will be 2026249127   12 Oct 2026 further described. As for the profile of the coupling, the shape differs in the radial direction, depending on the functions to perform. The following structures are provided within the range of the radius indicated by R1 in the Figure. 5

[0469] That is, the positioning hole (opening) 143a which engages with the positioning boss (positioning portion) 180i of the drive coupling 180, a visor (visor portion) 143g (see part (a) of Figure 47 and Figure 1) as a overhang portion for preventing the drive transmission unit 203 from entering in the axial direction and a part of the helical slope 143d are provided. A part of the helical slope 10   143d and a part of the braking force receiving surface 143c are provided in the range between R1 to R2. The braking force receiving surface 143c is not visible in the line-of-sight direction of part (a) of Figure 47 and is shown in Figure 1.In the range between R2 to R3, a part of the driving force receiving portion 143b, a part of the helical slope 143d, and a part of the braking force receiving surface 15   143c are provided.

[0470] On the other hand, since the shape of the drive transmission unit 203 is also arranged in a shape including a different role in the radial direction, the same range as the coupling 143 is shown in part (b) of Figure 47 using the same symbols R1 to R3. 20

[0471] Within the range of the radius indicated by R1 in part (b) of Figure 47, the positioning boss 180i that engages with the positioning hole 143a of the drum coupling 143 and the second brake that comes into contact with the visor portion 143g depending on the phase of the drum coupling 143. An inward projection 208e, which is a portion of the coupling engaging portion 208b of the engaging 25 member 208, is arranged. Within the range indicated by R1 to R2, the coupling engaging portion 208b of the second braking engagement member 208 is arranged. The drive transmission surface 180d and the first braking engagement 2026249127   12 Oct 2026 member 204 are arranged within the range indicated by R2 to R3.

[0472] Figure 48 is a developed view of these portions developed around the rotation axis M1. Figure 48 The process until the drum coupling 143 and the drive transmission unit 203 are engaged with each other will be described. 5

[0473] Figure 48 shows the drive transmission unit 203 on the lower side and shows the process of approaching the drum coupling 143 while moving in the direction of the arrow M1B until the engagement is established. In this Figure, the structures provided within the radius R1 shown in Figure 47 are shown by broken lines, the structures provided within the range between the radius R1 and 10 the radius R2 are shown by solid lines, and further, the structures provided in the range between the radius R2 to radius R3 are shown by solid lines and hatching lines.

[0474] The drum coupling 143 includes two coupling portions 143s and 143r arranged 180 ° apart from each other, but only the coupling portion 143s will be 15 described below for the sake of simplicity. The description of the coupling portion 143s also applies to the coupling portion 143r.

[0475] Part (a) of Figure 48 shows a state in which the drive transmission surface 180d of the drive transmission unit 203 and the second braking engagement member 208 are in close to each other. As shown in part (a) of 20 Figure 48, the phases of the inclination start portion 143f of the drum coupling 143 and the inward projection 208e of the second braking engagement member 208 have the following relationship. That is, the inclination start portion 143f of the drum coupling 143 is on the upstream side of the projection 208e in the rotational direction (arrow A). 25

[0476] Part (b) of Figure 48 shows a state in which the drive transmission unit 203 is further moved in the direction of arrow M1B from the position shown in part (a) of Figure 48. The helical slope 143d is opposed to and is in contact with 2026249127   12 Oct 2026 the inward projection 208e of the approaching first braking engagement member 204.

[0477] Part (c) of Figure 48 shows a state in which the drive transmission unit 203 is further moved in the direction of the arrow M1B. The helical slope 143d 5 stops the approaching second braking engagement member 208. By this, the movement of the second braking engagement member 208 in the M1B direction is suppressed. On the other hand, the portion excluding the second braking engagement member 208 (that is, the drum drive coupling 180 of the drive transmission unit 203, and so on) is moving in the direction of arrow M1B. In 10 the drive transmission unit 203, the second braking engagement member 208 is in a state of being relatively pushed in the direction of the arrow M1A.

[0478] In this state reached, as described referring to Figure 44, the second braking engagement member 208 can rotate without receiving a rotational load because of being disconnected from the brake member 206. At this time, the 15 brake member 206 receives an elastic force F1 in the direction of the rotation axis M1 by the drum drive coupling spring 210 and the brake engagement spring 211 provided inside the drive transmission unit 203. The helical slope 143d moves the second braking engagement member 208, which becomes free of rotational load, in the direction of arrow C by the component force of the elastic force F1. 20 That is, the second braking engagement member 208 moves to the downstream side in the rotational direction A along the helical slope 143d.

[0479] Part (d) of Figure 48 shows a state immediately after the second braking engagement member 208 is moved to the downstream side in the rotational direction (direction of arrow A). The second braking engagement 25 member 208 moves along the helical slope 143d of the drum coupling 143, and further moves in the M1B direction by the amount of the entire drive transmission unit 203 moving in the axial direction M1B, so that movement trace 2026249127   12 Oct 2026 is as depicted by the arrow D. As a result, the second braking engagement member 208 moves away from the drive coupling 180 toward the downstream side in the rotational direction A to the position in which it is engageable with the braking force receiving portion 143c (second side surface, second side portion) of 5 the drum coupling 143. That is, the helical slope 143d is a guide for guiding the braking engagement member toward the braking force receiving portion 143c. In this embodiment, the helical slope (top surface) 143d, which is a guide, has a downstream portion 143d1 and an upstream portion 143d2. The downstream portion (downstream side slope, downstream side top surface, downstream side 10 inclined portion) 143d1 is placed between the braking force receiving portion 143c and the driving force receiving portion 143b. The upstream side portion (upstream side slope, upstream side top surface, upstream side inclined portion) 143d2 is on the upstream side in the rotational direction (A direction) with respect to the driving force receiving portion 143b. Therefore, the second 15 braking engagement member 208 can be smoothly guided from the upstream side portion 143d2 of the slope 143d to the braking force receiving portion 143c by way of the downstream side portion 143d1.

[0480] Part (e) of Figure 48 shows a state in which the drum coupling 143 moves (rotates) in the direction of arrow A by the rotating drive transmission 20 surface 180d, and as a result, the braking force receiving portion 143c contacts the second braking engagement member 208.

[0481] When the drive transmission unit 203 rotates in the direction of arrow A, the drive transmission surface 180d comes into contact with the drive force receiving portion 143b to transmit the drive force. The drive transmission 25 surface 180d is a drive force applying portion which applies a drive force to the drum coupling 143.

[0482] The drum coupling 143 being rotated by receiving the driving force 2026249127   12 Oct 2026 from the driving transmission surface 180d also receives the braking force by the braking force receiving portion 143c contacting (engaging) the second braking engagement member 208.

[0483] Parts (a) to (e) of Figure 48 show only the second braking engagement 5 member 208 out of the first and second braking engagement members 204 and 208 which are the braking engagement members. However, the first braking engagement member 204 (see Figure 43) is connected to the second brake member 208 so as to move integrally with the second brake member 208. Therefore, in the process shown in part (a) of Figure 48 to part (e) of Figure 48, 10 the first braking engagement member 204 also moves along the same line as the second brake member 208. In the state shown in part (e) of Figure 48, the first braking engagement member 204 also engages with the braking force receiving portion 143c together with the second braking engagement member 208.

[0484] In part (a) to (e) of Figure 48, only the engagement process of the 15 braking engagement member (204, 208) and the drum drive coupling 180 with the coupling portion 143s are shown for simplicity of the description. Similarly to the coupling portion 143s, the coupling 143r also engages with the braking engagement member (204, 208) and the drum drive coupling 180. The engagement state of the braking engagement members (204, 208) and the drum 20 drive coupling with respect to the coupling 143r is shown in part (a) of Figure 76.

[0485] Here, in order to help the recognition of the process described so far, the description will be made again using the perspective views of Figures 60 to 64. In Figures 60 to 64, a part of the drum drive coupling 180 is not shown for better illustration, and the internal shapes are uncovered. 25

[0486] Figure 60 is a perspective view illustrating the same state as in part (a) of Figure 48 described above. That is, the inclination start portion 143f of the drum coupling 143 is on the upstream side of the projection 208e in the rotational 2026249127   12 Oct 2026 direction (arrow A), and the drive transmission surface 180d of the drive transmission unit 203 and the second braking engagement member 208 are close to each other. Figure 61 shows a state in which the drive transmission unit 203 has moved in the direction of arrow M1B from this state. 5

[0487] Figure 61 shows a state corresponding to part (b) of Figure 48, and the helical slope 143d is opposed to and is in contact with the inward projection 208e of the approaching second braking engagement member 208. The drive transmission unit 203 and the drum coupling 143 are relatively close to each other until they come into contact with each other, but the state inside the drive 10 transmission unit 203 has not changed.

[0488] Figure 62 shows a state in which the drive transmission unit 203 is further moved in the direction of arrow M1B from this state.

[0489] Figure 62 shows a state corresponding to part (c) of Figure 48, in which the helical slope 143d stops the approaching second braking engagement 15 member 208. By this, in the drive transmission unit 203, the second braking engagement member 208 is pushed in the direction of the arrow M1A relative to the drum drive coupling 180.

[0490] In this state, as described referring to Figure 44, the second braking engagement member 208 can rotate without receiving a rotational load because of 20 being disconnected from the brake member 206. At this time, the brake member 206 receives an elastic force F1 in the direction of the rotation axis M1 by the drum drive coupling spring 210 and the brake engagement spring 211 arranged inside the drive transmission unit 203. The helical slope 143d moves the second braking engagement member 208, which becomes free of rotational load, in the 25 direction of arrow C by the component force of the elastic force F1. That is, the second braking engagement member 208 rotationally moves to the downstream side in the rotational direction A along the helical slope 143d. 2026249127   12 Oct 2026

[0491] Figure 63 shows a state immediately after the second braking engagement member 208 moves to the downstream side in the rotational direction (direction of arrow A), and corresponds to part (c) of Figure 48. The second braking engagement member 208 moves along the helical slope 143d of 5 the drum coupling 143, and further moves in the M1B direction by the amount of movement of the entire drive transmission unit 203 in the axial direction M1B direction, the trace of the movement is as indicated by the arrow D. As a result, the braking engagement members (204, 208) move away from the drive coupling 180 toward the downstream side in the rotational direction A to the position in 10 which they can engage with the second side surface (braking force receiving portion 143c) of the drum coupling 143. At this position reached, the braking engagement members (204, 208) return to a state where braking force can be produced.

[0492] Figure 64 shows a state in which the drum coupling 143 is moved 15 (rotated) in the direction of arrow A by the rotating drive transmission surface 180d, and as a result, the braking force receiving portion 143c contacts the second braking engagement member 208. Figure 64 corresponds to part (d) of Figure 48.

[0493] When the drum drive coupling 180 of the drive transmission unit 203 20 rotates in the direction of arrow A from the state of Figure 64, the drive transmission surface 180d comes into contact with the drive force receiving portion 143b to transmit the drive force. The drum coupling 143 being rotated by receiving the driving force from the driving transmission surface 180d also receives the braking force by the braking force receiving portion 143c contacting 25 (engaging with) the second braking engagement member 208 (see part (e) of Figure 48).

[0494] In summary, through the processes shown in parts (a) to (e) of Figure 2026249127   12 Oct 2026 48 and Figures 60 to 64, the braking engagement members (204, 208) are moved relative to the drum drive coupling 180 and the drum coupling 143 as follows.

[0495] The braking engagement member (204, 208) is moved from the position (part (a) of Figures 48 and 60 in which it is close to the drive 5 transmission surface 180d to the position (part (d) of Figures 48 and 64) in which the drum coupling 143 is sandwiched between the drive transmission surface 180d and the braking engagement member (204, 208).

[0496] When the drive transmission surface 180d rotates from the state shown in part (d) of Figure 48 and Figure 64, the drum coupling 143 also rotates 10 together with the drive transmission surface 180d to reach the state shown in part (e) of Figure 48. Then, the drum coupling 143 rotates in the direction of arrow A by the driving force received from the drum driving side coupling 180 while receiving an appropriate load (braking force) from the braking engagement member (204, 208). As a result, the torque required for the drum drive coupling 15    180 to rotate the drum unit is not too light and is appropriate, so that the rotational drive of the drum unit is stabilized.

[0497] Next, referring to part (a) to (e) of Figure 49, another pattern of the engagement process of the drum drive coupling 180 and the braking engagement member (204, 208) with the drum coupling 143 will be described. The drum 20 coupling 143 has two coupling portions 143s and 143r, but for the sake of simplicity, only the coupling portion 143s will be described.

[0498] As shown in part (a) of Figure 49, a case where the phases of the inclination start portion 143f of the drum coupling 143 and the inward projection 208e of the second braking engagement member satisfy the following 25 relationship will be described. That is, the case where the inclination start portion 143f of the drum coupling 143 is on the downstream side in the rotational direction (arrow A) with respect to the inward projection 208e. 2026249127   12 Oct 2026

[0499] Part (a) of Figure 49 shows a state in which the drive transmission surface 180d of the drive transmission unit 203 and the second braking engagement member 208 are close to each other.

[0500] The visor portion 143g of the drum coupling 143 is in contact with the 5 inward projection 208e of the second braking engagement member 208 approaching in the M1B direction.

[0501] Next, part (b) of Figure 49 shows a state in which the visor portion 143g stops (blocks) the advancement of the approaching second braking engagement member 208. Here, the drum drive coupling 180, which is a 10 component of the drive transmission unit 203, does not contact the visor portion 143g, and therefore, the advancement in the M1B direction cannot be stopped. That is, the visor portion 143g does not interfere with the shape of the drum drive coupling 180 because the position thereof is different in the radial direction. On the other hand, the second braking engagement member 208 has an inward 15 projection 208e at the free end in the M1B direction. Since the inward projection 208e projects inward in the radial direction, it is in contact with the visor portion 143g of the drum coupling 143.

[0502] By the movement of only the drum drive coupling 180 in the M1B direction, the second braking engagement member 208 moves relative to the 20 drum drive coupling 180 in the M1A direction. As described above, by this relative movement, the second braking engagement member 208 shifted to a state in which it can rotate without receiving a rotational load.

[0503] Then, part (c) of Figure 49 shows a state in which the drive transmission unit 203 has started to rotate in the rotational direction A. First, 25 when the drum drive coupling 180 starts rotating in the A direction, it is pushed by the drum drive coupling 180, and the second braking engagement member 208 also starts rotating in the A direction. 2026249127   12 Oct 2026

[0504] The helical slope 143d of the drum coupling 143 moves the second braking engagement member in the direction of arrow C from the point where the inward projection 208e of the second braking engagement member 208 passes the inclination start portion 143f. That is, the second braking engagement member 5   208 moves toward downstream side in the rotational direction A and in the M1B direction.

[0505] Part (d) of Figure 49 shows a state after the second braking engagement member 208 moves along the helical slope 143d of the drum coupling 143 and passes the inclined surface 143d as in part (d) of Figure 48. 10 At this time, the entire drive transmission unit 203 further moves in the axial direction M1B. As a result, the second braking engagement member also moves in the M1B direction. The first braking engagement member 204 moves along the line of arrow D.

[0506] Subsequent engagement operation is the same as in the description of 15 part (d) of Figure 48, and the subsequent engagement completion state is as shown in part (e) of Figure 48. In this embodiment, visor portion 143g is continuous with on the upstream side (upstream side slope, upstream side top surface) 143d2 of the helical slope 143d. The inclination start portion 143f is a boundary portion between the visor portion 143g and the helical slope 143d. 20 Therefore, the second braking engagement member 208, the movement of which has been blocked by the visor portion 143g, can smoothly shift to a state of being in contact with the helical slope 143d, as the drive transmission unit 203 rotates. However, the structure is not necessarily limited to this example structure, and a space may be provided between the visor portion 143g and the slope 143d. 25

[0507] Also in part (a) of Figure 49 to part (d) of Figure 49, only the second braking engagement member 208 of the braking engagement members (204, 208) is shown. However, as described above, also in the process of part (a) of Figure 2026249127   12 Oct 2026 49 to part (d) of Figure 49, the first braking engagement member 204 (see Figure 43) moves integrally with the second braking engagement member 208.

[0508] Here, in order to help the recognition of the process described referring to part (a) of Figure 49 to part (d) of Figure 49, the description will be made again 5 with reference to the perspective views of Figures 65 to 68. In Figures 65 to 68, a part of the drum drive coupling 180 is not shown for better illustration, and the internal shape is uncovered.

[0509] Figure 65 shows a state in which the drive transmission surface 180d of the drive transmission unit 203 and the second braking engagement member 208 10 are close to each other. At this time, the visor 143g of the drum coupling 143 is in contact with the second braking engagement member 208 approaching in the M1B direction. Figure 65 corresponds to part (a) of Figure 49.

[0510] Next, Figure 66 shows a state in which the drum drive coupling 180 has moved to the right side (M1B direction) along the axial direction relative to 15 the second braking engagement member 208. In Figure 66, the visor portion 143g is in a state of stopping (blocking) the advancement of the approaching second braking engagement member 208.

[0511] Figure 66 corresponds to part (b) of Figure 49. The second braking engagement member 208 moves relative to the drum drive coupling 180 to the 20 left side (M1A direction) in the axial direction. As described above, by this relative movement, the second braking engagement member 208 is shifted to a state in which it can rotate without receiving a rotational load.

[0512] Subsequently, Figure 67 shows a state in which the drive transmission unit 203 has started to rotate in the rotational direction A. Figure 67 25 corresponds to part (c) of Figure 49. The helical slope 143d of the drum coupling 143 moves the second braking engagement member 208 in the direction of arrow C from the point where the second braking engagement member 208 2026249127   12 Oct 2026 passes the inclination start portion 143f. Figure 68 corresponds to part (d) of Figure 49. In the state shown in Figure 68, the first braking engagement member 204 moves along the helical slope 143d of the drum coupling 143, as in the state shown in part (d) of Figures 48 and 63. Further, the first braking 5 engagement member 204 also moves in the M1B direction by the amount of the movement of the entire drive transmission unit 203 in the axial direction M1B direction. As a result, the first braking engagement member 204 moves along the trace of arrow D.

[0513] Then, as described above, the entire drive transmission unit 203 10 continues to rotate to complete the connection, resulting in the same state as in part (e) of Figure 48.

[0514] Next, referring to part (a) of Figure 50 to part (d) of Figure 50, further pattern of the engagement process of the drum drive coupling 180 and the braking engagement member (204, 208) with the drum coupling 143 will be 15 described. The drum coupling 143 includes two coupling portions 143s and 143r, but for the sake of simplicity, only the coupling portion 143s will be described.

[0515] As shown in part (a) of Figure 50, a case where the phase of the inclination start portion 143f of the drum coupling 143 and the inward projection 20   208e of the second braking engagement member satisfy the following relationship will be described. That is, a case where the inclination start portion 143f of the drum coupling 143 is on the downstream side in the rotational direction (arrow A) will be described.

[0516] Part (a) of Figure 50 shows a state in which the drive transmission 25 surface 180d of the drive transmission unit 203 and the second braking engagement member 208 are separated from each other.

[0517] Next, part (b) of Figure 50 shows a state in which the visor portion 2026249127   12 Oct 2026 143g stops the advancement of the approaching second braking engagement member 208. Here, the drum drive coupling 180, which is a component of the drive transmission unit 203, does not contact the visor portion 143g, and therefore, the advancement cannot be stopped. By this, the second braking engagement 5 member 208 moves relative to the drum drive coupling 180 in the M1A direction. As described above, by this relative movement, the second braking engagement member 208 is shifted to a state in which it can rotate without receiving a rotational load. Here, the visor portion 143g does not interfere with the shape of the drum drive coupling 180 because the position is different in the radial 10 direction.

[0518] Then, part (c) of Figure 50 shows a state in which the drive transmission unit 203 rotates in the rotational direction A and contacts the second braking engagement member. That is the state in which the second braking engagement member 208 does not start rotating by itself, so that it stops at that 15 position, and the drum drive coupling 180 rotates and comes into contact with the second braking engagement member 208. Thereafter, by further rotation, the second braking engagement member 208 and the drum drive coupling 180 rotate integrally.

[0519] Part (d) of Figure 50 shows a state in which the second braking 20 engagement member 208 is further rotated and has passed the inclination start portion 143f of the drum coupling 143. In this state reached, the second braking engagement member 208 moves in the direction of arrow C as described referring to part (c) of Figure 48. The operation after this is the same as described above, and therefore, the description is omitted. 25

[0520] Also in part (a) of Figure 50 to part (d) of Figure 50, only the second braking engagement member 208 of the braking engagement members (204, 208) is shown. However, as described above, also in the process of part (a) of Figure 2026249127   12 Oct 2026 50 to part (d) of Figure 50, the first braking engagement member 204 (see Figure 43) moves integrally with the second braking engagement member 208.

[0521] Here, in order to help the recognition of the process described referring to part (a) of Figure 50 to part (d) of Figure 50, the description will be made again 5 with reference to the perspective views of Figures 69 to 72. In Figures 69 to 72, a part of the drum drive coupling 180 is not shown for better illustration, and the internal shape is uncovered.

[0522] Figure 69 corresponds to part (a) of Figure 50, and shows a state in which the drive transmission surface 180d of the drive transmission unit 203 and 10 the second braking engagement member 208 are separated by a gap G1.

[0523] Next, Figure 70 corresponds to part (b) of Figure 50 and shows a state in which the entire drive transmission unit 203 has moved in the M1B direction. That is the state in which the visor portion 143g stops the advancement of the approaching second braking engagement member 208, and the drum drive 15 coupling 180 has moved to the right side (M1B direction) in the axial direction beyond the second braking engagement member 208.At this time, the second braking engagement member 208 moves to the left side (M1A direction) relative to the drum drive coupling 180. As described above, by this relative movement, the second braking engagement member 208 is shifted to a state in which it can 20 rotate without receiving a rotational load.

[0524] Then, Figure 71 corresponds to part (c) of Figure 50, and shows a state in which the drum drive coupling 180 of the drive transmission unit 203 is in contact with the second braking engagement member 208 by rotating in the rotational direction A. 25

[0525] Since the second braking engagement member 208 cannot rotate without receiving the rotational force from the drum drive coupling 180, the second braking engagement member 208 does not rotate immediately after the 2026249127   12 Oct 2026 start of driving of the drive transmission unit 203 and remains at the initial position. That is, only the drum drive coupling 180 starts rotating in the A direction in advance. As a result, a state shown in Figure 71 is reached in which the drum drive coupling 180 is in contact with the second braking engagement 5 member 208.

[0526] Figure 72 corresponds to part (d) of Figure 50, and shows a state in which by the engagement between the drum drive coupling 180 and the second braking engagement member 208, not only the drum drive coupling 180 but also the second braking engagement member 208 start to rotate in the direction A. 10 More specifically, that is the state in which by the second braking engagement member 208 being pushed by the drum drive coupling 180 to rotate in the A direction, the second braking engagement member 208 passes the inclination start portion 143f of the drum coupling 143. In this state reached, the second braking engagement member 208 is guided by the slope 143d and moves in the direction 15 along the slope 143d (direction of arrow C), as described in part (c) of Figure 48 and Figure 62.

[0527] Subsequent operations are the same as those described above referring to part (c) of Figure 48 to part (e) of Figure 48 and Figures 62 to 64, and therefore, the description thereof are omitted here. 20

[0528] As described above, when the cartridge 100 is mounted on the image forming apparatus main assembly, the phase (arrangement) of the drive transmission unit 203 with respect to the drum coupling 143 is not predetermined (part (a) of Figure 48, Figure 49 (a), part (a) of Figure 50, Figure 60, Figure 65, Figure 69). However, in any case, the drum coupling 143 can be connected to 25 the drive transmission unit 203. The drive transmission unit 203 includes not only the drum drive coupling 180 but also the braking engagement members (204, 208), both of which the drum coupling 143 can be engaged with. 2026249127   12 Oct 2026

[0529] Next, referring to Figure 51, the description will be made as to the structures for aligning the axes of the drive transmission unit 203 and the drum coupling 143, in the process of connecting them. Figure 51 is a sectional view of the drive transmission unit 203 and the drum coupling 143, and part (a) of 5 Figure 51 shows the shapes in the connected state in this embodiment. The circular hole portion 143a of the drum coupling engages with the positioning boss 180i of the drum drive coupling 180 to align the axes with each other. Further, a conical guide surface 143h is provided at one end of the circular hole portion 143a. That is, the guide surface 143h has a conical shape as a part of the inner 10 surface of the coupling 143. The guide surface 143h is provided so that when the drive transmission unit 203 is still separated in the axial direction M1B direction, the deviations from each other are eliminated upon starting engagement to align the axes with each other.

[0530] In addition to this embodiment, the circular hole portion 143a of the 15 drum coupling 143 may be engaged with the positioning boss 180i without providing a guide surface, as shown in part (b) of Figure 51. Further, as shown in part (c) of Figure 6, the guide surface 143h can be enlarged to reduce the fitting between the circular hole portion 143a and the positioning boss 180i. Further, as shown in part (d) of Figure 51, the diameter of the circular hole 20 portion 143a can be increased. These arrangements can be selected depending on how to determine the relative position between the drive transmission unit 203 and the process cartridge 100 and the accuracy.

[0531] It is desirable that the circular hole portion 143a has a sufficient length to accommodate the positioning boss 180i. That is, as shown in Figure 95, the 25 positioning boss 180i enters at least the range of the region Pb on the axis L of the drum unit. The circular hole portion 143a is formed so as to include the entire region Pb. That is, the periphery of the axis L is open in the region Pb. 2026249127   12 Oct 2026

[0532] In Figure 95, in this embodiment, on the axis L, the range occupied by the braking force receiving portion 143c, the helical slope (top surface) 143d, the visor portion 143g, and the driving force receiving portion 143b (not shown) is Pa which is included inside the region Pb. 5

[0533] The structure is such that projection area Pa when the braking force receiving portion 143c, the slope 143d, the visor portion 143g, and the driving force receiving portion 143b are projected onto the axis L at least partially overlap the projection region Pb of the circular hole portion 143a.

[0534] As described above, according to this embodiment, the coupling 143 of 10 the cartridge receives the driving force from the drive transmission unit 203 of the image forming apparatus main assembly. Further, the coupling 143 operates the brake mechanism (brake member 206) inside the drive transmission unit 203 in accordance with receiving the driving force from the drive transmission unit 203. The drum coupling 143 can receive the braking force by way of the 15 braking engagement member (204, 208).

[0535] With this brake mechanism, the load required to drive the cartridge can be set in an appropriate range. As a result, the cartridge 100 can be driven stably.

[0536] It is also possible to use the drum coupling 104 and the drive 20 transmission unit 203 of this embodiment to rotate members other than the photosensitive drum 104, such as a developing roller and a toner feeding roller. However, the drum coupling 104 and the drive transmission unit 203 of this embodiment are particularly suitable for rotation of the photosensitive drum 104, for the following reasons. 25

[0537] While the cartridge 100 of this embodiment includes the photosensitive drum 104, it is not provided with a cleaning means contacting the photosensitive drum 104. Therefore, the torque of the photosensitive drum 104 is relatively 2026249127   12 Oct 2026 small, and the speed of the photosensitive drum 104 tends to fluctuate when it is affected by the surroundings during rotational driving thereof. For this reason, the drive transmission unit 203 rotates the photosensitive drum 104 with a constant load applied to the drum 104. That is, the coupling 143 not only 5 receives the driving force for rotating the photosensitive drum, but also receives the braking force for suppressing the rotation of the photosensitive drum from the drive transmission unit 203. By simultaneously receiving two forces acting on the coupling in different rotational directions, the speed fluctuation of the photosensitive drum 104 (drum unit 103) is suppressed, and the rotation is 10 stabilized.

[0538] The driving force can be inputted from the drive transmission unit 203 of this embodiment to the cartridge provided with the cleaning means by way of the coupling 143. When the cartridge 100 is provided with a cleaning means (, for example, a cleaning blade) which contacts the surface of the photosensitive 15 drum to remove toner from the photosensitive drum, a frictional force is produced between the photosensitive drum and the cleaning means. This frictional force increases the torque required to rotate the photosensitive drum 104. However, even so, the torque required to rotate the photosensitive drum 104 may not be sufficiently large. At this time, as in this embodiment, if the coupling 143 can 20 receive the driving force and the braking force from the drive transmission unit 203 at the same time, the torque required to rotate the photosensitive drum 104 increases, and therefore, the rotation of the photosensitive drum is stabilized. A cartridge provided with a cleaning means will be described in Embodiment 2 described hereinafter. 25

[0539] In this embodiment, the brake mechanism for applying an appropriate rotational load to the photosensitive drum is arranged not on the cartridge side but on the main assembly side of the image forming apparatus, more particularly, in 2026249127   12 Oct 2026 the drive transmission unit 203. Therefore, it is not necessary to provide the brake mechanism on the process cartridge which is the object (dismountably mountable unit) to be replaced after use. It can contribute to the downsizing and cost reduction of the process cartridge. 5

[0540] Further, the coupling 143 has such a shape that it can smoothly engage with both the driving force applying member (drum drive coupling 180) and the braking force applying member (braking engagement member (204, 208)) provided in the drive transmission unit 203. For example, the coupling 143 is provided with a helical slope 143d (inclined portion, guide, upper surface, upper 10 portion) and a visor portion 143f, so that it can be easily connected to the drive transmission unit 203 smoothly.

[0541] Hereinafter, the shape of the coupling 143 of this embodiment will be described in detail again referring to Figure 79.

[0542] The coupling 143 includes two coupling portions 143s and 143r, and 15 each coupling portion includes an engaging portion 143i and a guide forming portion 143j. The engaging portion 143i is a shaped portion for engaging with the driving force applying member (drum drive coupling 180) or the braking force applying member (braking engagement member (204, 208)). The engaging portion 143i forms a driving force receiving portion 143b, a braking 20 force receiving portion 143c, and a downstream slope 143d1.

[0543] The driving force receiving portion 143b and the braking force receiving portion 143c engage with the drum drive coupling 180 and the brake members (204, 208), respectively. The driving force receiving portion (first side surface, first side portion) 143b and the braking force receiving portion (second 25 side surface, second side portion) 143c are formed in a planar shape, but they are not limited to such a structure. They may be a curved surface-shaped portion or a portion having a small area, as long as they can receive a driving force and a 2026249127   12 Oct 2026 braking force, respectively. For example, the edge (ridge line) formed by the engaging portion 143i may form the driving force receiving portion (first side surface, first side portion) 143b or the braking force receiving portion (second side surface, second side portion) 143c. 5

[0544] Alternatively, the driving force receiving portion 143b and the braking force receiving portion 143c may be a portion formed by a plurality of separate regions. That is, the engaging portion 143i may be a set of a plurality of shaped portions. 10

[0545] The driving force receiving portion 143b and the braking force receiving portion 143c are an upstream side portion and a downstream side portion of the engaging portion 143i, respectively. That is, the driving force receiving portion 143b is a side portion directed upstream in the rotational direction, and the braking force receiving portion 143c is a side portion directed 15 downstream in the rotational direction.

[0546] Further, the guide forming portion 143n is a projection (extending portion) extending in the rotational direction toward the engaging portion 143i. The top surface (upper part) of the guide forming portion 143n is an upstream side slope (upstream side top surface, upstream side inclined portion) 143d2. 20 The upstream slope 143d2 is a guide (upstream guide, upstream guide) and an inclined portion for guiding the braking force applying member (braking engagement member (204, 208)) toward the engaging portion 143i.

[0547] That is, the guide forming portion 143n is a projection for forming the upstream side slope 143d2 which is a guide (upstream side guide). 25

[0548] The guide forming portion 143n is adjacent to the engaging portion 143i and extends from the upstream to the downstream in the rotational direction toward the engaging portion 143i. Further, the upstream slope 143d2 of the 2026249127   12 Oct 2026 guide forming portion 143n is inclined so as to approach the non-driving end of the photosensitive drum from the upstream to the downstream in the rotational direction (see Figure 80).

[0549] In Figure 80, the drum coupling 143 is placed in the neighborhood of 5 the first end portion (driving side end portion) 104a of the photosensitive drum 104. That is, the first end portion 104a of the photosensitive drum 104 is the end portion on the side for receiving the driving force from the drum coupling 143.

[0550] The end on the opposite side of the photosensitive drum 104 with 10 respect to the first end portion 104a is the non-driving side end (second end) 104b. The distances from the non-driving side end portion 104b to the upstream side slope 143d2 are indicated by D1 and D2. The distance D1 is a distance measured from the non-driving side end portion 104b of the photosensitive drum to the downstream end of the slope 143d2 along the axial direction parallel to the 15 axis L. The distance D2 is a distance measured along the axial direction from the non-driving side end portion 104b of the photosensitive drum to the upstream side end portion of the upstream side slope 143d2.

[0551] Here, the distance D1 is shorter than the distance D2. That is, when the distance from the non-driving end portion 104b of the photosensitive drum to 20 the upstream slope 143d2 is measured along the axial direction, the distance becomes shorter toward the downstream in the rotational direction.

[0552] That is, the upstream side slope 143d2 is inclined so as to approach the non-driving side end portion 104b of the photosensitive drum toward the downstream side in the rotational direction A. Not only the upstream slope 25   143d2 but also the downstream slope 143d1 is inclined in the same direction.

[0553] The distances D1 and D2 can also be regarded as the distances measured along the axial direction from the non-driving side end of the cartridge 2026249127   12 Oct 2026 casing (that is, the non-driving side cartridge cover 117: see Figure 14) to the upstream slope 143d2.

[0554] One of the guide forming portion 143n and the engaging portion 143i may be referred to as a first shape portion, and the other may be referred to as a 5 second shape portion or the like.

[0555] In this embodiment, the first shape portion and the second shape portion (that is, the guide forming portion 143n and the engaging portion 143i) are adjacent to each other and are connected to each other. More specifically, the downstream side of the guide forming portion 143n in the rotational direction 10 is connected to the engaging portion 143i. However, although the engaging portion 143i and the guide forming portion 143n are adjacent to each other, they may not be connected with a gap provided therebetween.

[0556] Further, in this embodiment, the top surface (downstream side slope) 143d1 of the engaging portion 143i is smoothly connected to the top surface 15 (upstream side slope) 143d2 of the guide forming portion 143n to provide a one slope (top surface) 143d.

[0557] That is, the top surface (downstream side slope) 143d2 of the engaging portion 143i is a part of the guides having a function of guiding the braking engagement member (204, 208) to a position where it can engage with the 20 braking force receiving portion 143c, similarly to the upstream side slope 143d1.

[0558] The downstream slope (downstream top surface) 143d2 does not necessarily have to be continuous with the upstream slope (upstream top surface) 143d1. Examples of the non-continuous form of the upstream slope 143d2 and the downstream slope 143d1 are as shown in part (a) of Figure 81 and part (b) of 25 Figure 81. In part (a) of Figure 81 and part (b) of Figure 81, a modified example is shown in which the upstream slope 143d2 and the downstream slope 143d1 are provided with a step, and are separated in the axial direction, and the 2026249127   12 Oct 2026 downstream slope 143d1 is changed to a flat surface. As described above, a part of the helical slope 143d which is a guide may be flat or may have a step.

[0559] As shown in part (c) of Figure 48, part (c) of Figure 49, part (d) of Figure 50, Figure 62, Figure 67, and Figure 72, the braking engagement members 5   (204, 208) are brought into contact with the slope 143d to be guided in the direction of arrow C along the inclination direction of the slope 143. That is, the braking engagement member (204, 208) moves in the direction downstream in the rotational direction toward the non-driving side of the photosensitive drum (M1B direction). 10

[0560] After being guided by the slope 143d, the braking engagement member (204, 208) is further advanced in the axial direction (M1B) toward the space placed downstream of the braking force receiving portion (second side surface) 143c of the drum coupling 143 (See part (d) of Figure 48, part (d) of Figure 49, Figure 63, Figure 68). As a result, the braking engagement members (204, 208) 15 are enabled to engage with the braking force receiving portion 143c.

[0561] The braking engagement member (204, 208) being guided by the slope 143d, the braking engagement member (204, 208) moves to the downstream side in the rotational direction A so as to be away from the drum drive coupling 180. As a result, the gap is produced between the drum drive coupling 180 and the 20 braking engagement members (204, 208). The engaging portion 143i of the drum coupling 143 enters the gap, so that the driving force receiving portion (side surface) 143b is enabled to engage with the drum drive coupling 180 (see part (d) of Figure 48, part (e) of Figure 48, part (d) of Figure 49, Figure 63, Figure 64, Figure 68). 25

[0562] The helical slope 143d also has a function of keeping the braking engagement members (204, 208) away from the drum drive coupling 180 so that the drum drive coupling 180 and the drive force receiving portion 143b can 2026249127   12 Oct 2026 engage with each other.

[0563] The helical slope (top surface) 143d has not only the portion (downstream side guide, downstream guide, downstream side top surface, downstream side inclined portion) 143d1 arranged between the braking force 5 receiving portion 143c and the driving force receiving portion 143b but also has the portion (upstream guide, upstream top surface, upstream inclined portion) 143d2 on the upstream side of the driving force receiving portion 143b (see part (a) of Figure 48, Figure 47, Figure 56, and so on). By enlarging the area where the slope 143d is provided, the top surface 143d can reliably guide the braking 10 engagement members (204, 208).

[0564] That is, even when the braking engagement member (204, 208) is placed on the upstream side of the driving force receiving portion 143b (see part (a) of Figure 49) the braking engagement members (204, 208) can be moved to the space on the downstream side of the braking force receiving portion 143c (see 15 part (c) of Figures 49 and 49 (d)), by passing the upstream slope 143d2.

[0565] In this embodiment, the entire slope 143d is the inclined portion. The downstream top surface 143d1 and the upstream side top surface 143d2 are both descending slopes which descend toward the downstream in the rotational direction. 20

[0566] However, it is also possible to incline only a part of the slope 143d which is the top surface. For example A structure is also conceivable (see part (a) of Figure 81 and part (b) of Figure 81) in which, the upstream side of the top surface is inclined as the upstream side slope 143d2, as described above, whereas the downstream side of the top surface (downstream side top surface 143d2) is 25 not inclined and is a surface perpendicular to the axis of the drum unit. In the modified example of the drum coupling shown in part (a) of Figure 81 and part (b) of Figure 81 , the braking engagement member (204, 208) is vigorously 2026249127   12 Oct 2026 moved by the inclination of the upstream slope (upstream top surface) 143d2, and by utilizing the inertia (momentum) of the movement, it passes the flat downstream top surface 143d1.

[0567] Further, as a guide for guiding the braking engagement members (204, 5   208), it is conceivable that only the upstream side top surface (upstream side slope 143d2) is used and the downstream side top surface (downstream side slope 143d1) is not used. That is, it is conceivable that there is almost no portion corresponding to the downstream top surface, or that the portion is very short as compared with the upstream top surface. Such a structure will be described 10 hereinafter referring to Figure 74.

[0568] It is also conceivable that there is provided a partial ascending portion in the downhill helical slope 143d. Even in such a case, if the braking engagement member (204, 208) can be sufficiently guided downstream in the rotational direction by the slope 143d, the slope 143d can be deemed as a 15 downhill slope. That is, even if the slope is partially ascending, the helical slope 143d can be regarded as a descending slope as a whole. In other words, the distance from the non-driving end of the cartridge to the helical slope 143d can be considered as decreasing as the helical slope 143d moves downstream in the rotational direction. 20

[0569] As an example of such, a structure is conceivable in which the ascending portion partially provided in the helical slope 143d is sufficiently shorter than the other descending portions, or the ascending slope is less steep, and therefore, the ascending portion has a small influence on the descending portion. 25

[0570] Further, there is a case in which the helical slope 143d has a curved surface shape or is divided into a plurality of sections. Furthermore, there is a case in which the width of at least a part of the slope 143d is so small that the 2026249127   12 Oct 2026 helical slope 143d may be regarded as a ridge line (edge) rather than a surface. The helical slope 143d has had a sector shape (helical shape) as the drum coupling 143 is viewed from the front side. However, the shape of the guide (top surface, inclined portion) to be provided on the drum coupling 143 is not 5 limited to such a shape. For example, instead of using a sector-shaped (helical) slope 143d, a linearly extending rectangular slope may be used. That is, as the inclined portion (guide, top surface) corresponding to the helical slope 143d, it is possible to use a structure having a changed shape, size, extending direction, and the like. Some of such examples will be described hereinafter referring to 10 Figure 54 and so on.

[0571] The upstream slope (upstream top surface) 143d2 is structured to have a region narrower than the downstream slope (downstream top surface) 143d1 (see Figures 47 and 56). Conversely, the downstream slope 143d1 has a region wider than the upstream slope 143d2. 15

[0572] Here, the width of each slope is a length measured along the radial direction. Further, as shown in Figure 79, at least a part of the engaging portion 143i is placed more remote than the guide forming portion 143n with respect to the axis L of the drum unit in the radial direction of the drum unit. In other words, at least a part of the engaging portion 143i is placed radially outside the 20 guide forming portion 143n.

[0573] The reason for such a dimensional relationship and such an arrangement relationship is that the driving force receiving portion 143b of the engaging portion 143i is disposed near the boundary between the guide forming portion 143n and the engaging portion 143i. That is, a part of the engaging 25 portion 143i overhangs outward in the radial direction from the guide forming portion 143n so that the driving force receiving portion 143b is formed. By this, the width of the downstream portion 143d1 of the slope (top surface) 143d is 2026249127   12 Oct 2026 larger than that of the upstream portion 143d2.

[0574] The driving force receiving portion 143b has a region placed radially outside (a position far from the axis L) with respect to the upstream slope 143d2. Further, in the axial direction of the drum unit, the driving force receiving portion 5   143b is disposed closer to the non-driving side end portion of the photosensitive drum than the upstream side slope 143d2. In Figure 80, a state is shown in which the distance D3 measured along the axial direction from the non-driving side end portion 104b of the photosensitive drum to the driving force receiving portion 143b is shorter than the distance D1 measured along the same direction to 10 the upstream top surface 143d2 from the non-driving side end portion 104b of the photosensitive drum.

[0575] Conversely, at least a part of the upstream slope 143d2 is placed at a distance from the driving force receiving portion 143b than the non-driving side end portion 104b of the photosensitive drum in the axial direction. The 15 upstream slope 143d2 is a free end portion placed closer to the free end of the drum coupling 143 than the driving force receiving portion 143b.

[0576] The distances D1 and D3 can be regarded as being the distances measured from the non-driving side end of the cartridge (that is, the non-driving side cartridge cover 117: see Figure 14)to the upstream slope 143d2 and the 20 driving force receiving portion 143b, in the axial direction.

[0577] The visor portion 143d is a block portion (stopper) which suppresses (blocks) the movement of the braking engagement member (204, 208) in the axial direction. That is, the visor portion 143d blocks the braking engagement member (204, 208) from approaching the drum coupling 143 and entering the 25 region where it cannot engage with the braking force receiving portion 143c. Figure 66, part (b) of Figure 49, Figure 69, part (a) of Figure 50 show the blocked state. 2026249127   12 Oct 2026

[0578] In this embodiment, the visor portion (block portion) 143d is further upstream in the rotational direction than the upstream slope 143d2, and the visor portion 143d is continuous with the top surface (upstream slope 143d2) of the guide forming portion 143n (See part (d) of Figure 56). 5

[0579] When the braking engagement member (204, 208) enters the space upstream of the driving force receiving portion 143b or the space downstream of the braking force receiving portion 143c together with the drum drive coupling 180, the braking engagement member (204, 208) 208) cannot engage with the braking force receiving portion 143c. The visor portion 143g blocks the 10 movement of the braking engagement members (204, 208) so as to prevent the occurrence of such a state.

[0580] In this embodiment, as the drum unit is viewed from the driving side along the axial direction (see part (a) of Figure 47), the visor portion 143g of the first coupling portion 143s is disposed such that it covers the space upstream of 15 the drive force receiving portion 143b. Further, the visor portion 143g is provided so as to cover the space downstream of the braking force receiving portion 143c.

[0581] Further, the visor portion 143d has a width sufficient to cover at least a part of the downstream side portion (downstream side slope 143d1) of the helical 20 slope (top surface) 143d. By this, the visor portion 143d constrains the braking engagement member (204, 208) from non-preferably entering the space on the upstream side of the driving force receiving portion 143b and the space downstream of the braking force receiving portion 143c together with the drum drive coupling 180. 25

[0582] On the other hand, the visor portion 143g is disposed so as to permit the braking engagement member (204, 208) to enter the space on the downstream side of the braking force receiving portion independently of the drum drive 2026249127   12 Oct 2026 coupling 180 (See part (d) of Figure 50, part (c) of Figure 49, part (c) of Figure 48).

[0583] That is, the braking engagement member (204, 208) contacts the upstream slope 143d2 after passing the visor portion 143g, and is guided along 5 the slope 143d toward the space on the downstream side of the braking force receiving portion 143c (See part (c) of Figure 49 and part (d) of Figure 50).

[0584] That is, when the braking engagement member (204, 208) is enabled to contact u portion (upstream side top surface) 143d2 of the slope (top surface) 143d, the visor portion 143g releases the braking engagement member (204, 208) 10 from the blocked state.

[0585] The visor portion 143g is adjacent to the upstream slope 143d2 and is upstream of the upstream slope 143d2. In this embodiment, the top surface of the visor portion 143g and the upstream slope 143d2 are continuous, but there may be a case in which the visor portion 143g and the upstream slope 143d2 are 15 adjacent to each other and a gap is formed between them.

[0586] Further, the top surface of the visor portion 143g has a plane perpendicular to the axis L of the drum unit, but the shape is not limited to this example. For example, it is conceivable that the top surface of the visor portion 143g is inclined in the same direction as with the upstream slope 143d2. In such 20 case, it can be considered that the visor portion 143g forms a part of the upstream slope 143d2. Alternatively, it can be considered that a part of the guide forming portion 143n forms the visor portion 143g.

[0587] Further, in this embodiment, the coupling 143 comprises two of the helical slopes 143d, two of the visor portions 143g, two of the driving force 25 receiving portions 143b, and two of the braking force receiving portions 143c. That is, the coupling 143 has a shape symmetrical with respect to its axis, and comprises two coupling portions 143s and 143r (see Figure 58). The coupling 2026249127   12 Oct 2026 portion 143s and the coupling portion 143r each have the helical slope (inclined portion) 143d or the like as the top surfaces. Then, the braking engagement member (204, 208) and the drum driving member 180 engage with the coupling portion 143s and the coupling portion 143r as shown in part (a) of Figure 76. 5

[0588] An example (modified example) of another shape of the coupling 143 will be described hereinafter.

[0589] The drive transmission unit 203 includes the first braking engagement member 204 and the second brake engagement member 208 as the braking force applying members (braking engagement members) which apply a braking force 10 for imparting a load to the rotation of the photosensitive drum to the coupling 143. There is a gap between the first braking engagement member and the second braking engagement member 208, and the second braking engagement member provided radially inward is flexible slightly to move outward so as to approach to the first braking engagement member 204. When the coupling and the drive 15 transmission unit 203 are disengaged from each other,, the second braking engagement member 208 can smoothly break the engagement with the coupling 143by the flexing of the second braking engagement member 208,. For example, the second braking engagement member 208 can move over the visor portion 143g by flexing and can be separated from the coupling 143. 20 [Various modifications of coupling and cartridge shown in Embodiment 1]

[0590] Modified examples (modified shape) in which the drum coupling 143 of the Embodiment 1 described above is partially modified will be described. Even when the above-described the visor portion 143g is not provided on the 25 drum coupling 143, it can function properly, depending on the conditions.

[0591] Figure 52 shows a perspective view of the drum coupling 143 in which the visor portion 143g is not provided, and Figure 53 shows a developed view 2026249127   12 Oct 2026 illustrating the process of engagement.

[0592] The shape will be described referring to Figure 52. Figure 52 is a view illustrating one end of the drum unit, and shows a state in which the coupling member (drum coupling) 143 is mounted to the end portion of the 5 photosensitive drum 104. The drum coupling 143 includes the helical slope 143d and a push-back surface 143k, which will be described hereinafter, but does not have a visor shape.

[0593] Subsequently, the process of engaging with the drive transmission unit 203 will be described referring to Figure 53. 10

[0594] The representation of the development view of Figure 53 is the same as with the development view of Figure 48. The drum coupling 143 comprises two coupling portions 143s and 143r, but only the coupling portion 143s will be described for the sake of simplicity of explanation. The description of the coupling portion 143s also applies to the coupling portion 143r. 15

[0595] The case where the phases of the inclination start portion 143f of the drum coupling 143 shown in part (a) of Figure 53 and the inward projection 208e of the second braking engagement member satisfy the following relationship will be described. That is, a case where the inclination start portion 146f of the drum coupling 143 is on the downstream side in the rotational direction (arrow A) will 20 be described.

[0596] Part (a) of Figure 53 shows a state in which the drive transmission surface 180d of the drive transmission unit 203 and the second braking engagement member 208 are close to each other.

[0597] Next, in part (b) of Figure 53, since there is no such visor portion as 25 described in embodiment 1, in the drum coupling 143, the drum drive coupling and the second braking engagement member 208 advance into the space between the push-back surface 143k and the helical slope 143d3. 2026249127   12 Oct 2026

[0598] Part (c) of Figure 53 shows a state in which the drive transmission unit 203 has started to rotate in the rotational direction A. When the drum drive coupling 180 and the second braking engagement member 208 rotate, the second braking engagement member 208 moves in the direction of arrow E along the 5 slope by the function of the inclination 01 of the push-back surface 143k or the function of the inclination 02 of the second braking engagement member 208. As described referring to Figure 48, the second braking engagement member 208 can rotate without receiving a rotational load.

[0599] As described above, when the braking engagement member (204, 208) 10 enters the region where it cannot engage with the braking force receiving portion, the push-back surface (push-back portion) 143k applies a force to the second braking engagement member 208. By this, the push-back surface 143k pushes back the braking engagement members (204, 208) toward the inside of the drive transmission unit 203 and moves it in the direction of arrow E. 15

[0600] However, the second braking engagement member 208 is urged by the spring 211 shown in Figure 43 in the M1B direction in the Figure, and if the component force of the inclination 02 of the second braking engagement member 208 is smaller than the spring force F1, the second braking engagement member 208 cannot be moved in the direction of arrow E. The component force changes 20   depending on the load torque of the drum holding unit 108 and the angle of each slope (01 or 02). It is preferable to set the magnitude relation of the force within the range in which the above function is performed in consideration of the component force and the frictional force.

[0601] Part (d) of Figure 53 shows the movement of the second braking 25 engagement member 208 which is no longer subjected to the rotational load. The drive transmission unit 203 has further rotated, and the second braking engagement member 208 is in a state of passing the inclination start portion 146f 2026249127   12 Oct 2026 of the drum coupling 146. In this state reached, the second braking engagement member 208 moves in the direction of arrow C as described referring to part (c) of Figure 48. The operation after this is the same as described above, and therefore, the description thereof will be omitted. 5

[0602] Although not shown in part (a) of Figure 50 to part (d) of Figure 50, the first braking engagement member 204 also moves together with the second braking engagement member 208 in these processes.

[0603] In the drum coupling 143 shown in the Embodiment 1 (see part (a) of Figure 1, the braking engagement member (204, 208) is blocked by the visor 10 portion 143g from entering the region in which it cannot engage with the braking force receiving portion. On the other hand, in the drum coupling 143 of this modified example, when the braking engagement member (204, 208) enters the region where the braking force receiving portion 143c cannot be engaged with the drum drive coupling 180, the braking engagement member (204, 208) is pushed 15 back by the push-back surface (push-back) 143k. The push-back surface 143k is an inclined portion inclined in a direction different from that of the helical slope 143. More particularly, the helical slope 143 is a portion which inclines toward the non-driving side of the drum unit as it goes downstream in the rotational direction, whereas the push-back surface 143k is a portion of the drum 20 unit which inclines toward the outside, that is, away from the non-driving side end portion 104b (see Figure 80) of the photosensitive drum, as it goes downstream in the rotational direction A. If the helical slope 143 is regarded as a descending slope, the push-back surface 143k is an ascending slope. The push-back surface 143k is placed on the upstream side in the rotational direction 25 with respect to the helical slope 143d, and is adjacent to the helical slope 43k.

[0604] The push-back surface 143k is also a guide (second guide) for guiding the braking engagement member (204, 208) toward the helical slope 143d. 2026249127   12 Oct 2026 Further, the push-back surface 134k is a helical slope (second helical slope, second inclined portion) having a direction of inclination opposite to that of the helical slope 143d.

[0605] Further, another modified shape of the drum coupling 143 will be 5 described. The inclined portion and the top surface (helical slope 143d) as the guide described in the Embodiment 1 are formed as smooth slopes, and guide the braking engagement members (204, 208) along such slope surfaces (See Figure 56 and the like). However, the drum coupling 143 can also function even if the inclined portion has other shapes. An example thereof is shown in Figure 54 in 10 a perspective view.

[0606] First, the shape shown in part (a) of Figure 54 is a reproduction of the shape described in the Embodiment 1. A gentle helical slope 143d is formed from the inclined starting portion 143f toward the braking force receiving portion 143c. 15

[0607] On the other hand, the shapes of part (b) of Figure 54 and part (a) of Figure 73 show modified examples. The height changes stepwise between the inclination start portion 147f and the braking force receiving portion 147c. That is, the top surface (inclined portion) has a stepped portion 147d, and the inclined portion is formed by the plurality of steps. Thus, the inclined portion (top 20 surface) may not be a helical slope but may be a helical step shape providing an inclination which lowers in the direction of advancement of the second braking engagement member 208.

[0608] The stepped step portion 147d moves the second braking engagement member 208 by moving the stepped step portion 147d in the direction of the 25 arrow C in part (a) of Figure 73, whereby the same function as that of the helical slope 143d in part (a) of Figure 54 is performed. While the inclined surface 143d is an inclined portion comprising continuously inclined surfaces, the 2026249127   12 Oct 2026 stepped portion 147d can be regarded as an inclined portion provided by stepwise structure of a plurality of surfaces.

[0609] If it is difficult to form a helical slope 143d on the coupling 143 due to restrictions on the structure of the mold for manufacturing the coupling 143, a 5 stepped portion 147d may be used instead of the inclined surface 143d.

[0610] At this time, it is preferable that when the stepped portion 147d, which is the top surface, and the second braking engagement member 208 come into contact with each other, the second braking engagement member 208 is structured to be smoothly guided without being caught by the stepped portion 10   147d. For example, it is conceivable to sufficiently narrow the width of each surface of the stepped portion 147d. Further, in part (a) of Figure 73, the top surface (inclined portion, guide) is formed in a stepped shape by combining a plurality of surfaces, but the top surface (inclined portion, guide) may be formed by combining a plurality of curved surfaces, and a similar function can be 15 performed with such a structure. Similarly to the inclined surface 143d, the stepped portion 147d is a guide (inclined portion) for guiding the braking engagement member (204, 208) toward the braking force receiving portion by its own inclination.

[0611] Further, as shown in part (c) of Figure 54 and part (b) of Figure 73, the 20 top surface is divided into an inclined surface (upstream side top surface, downstream side top surface) 148d1 and an inclined surface (downstream side top surface, downstream side guide, downstream side) 148d2 with a gap 148g therebetween. Also in this case, if the second braking engagement member 208 has such a shape that does not cause catching when it comes into contact with the 25 top surface (148d1, 148d2), the top surface (148d1, 148d2) can function as a guide. Such a coupling can be used when there is a restriction in the structure of the mold for molding the coupling. 2026249127   12 Oct 2026

[0612] Further, part (d) of Figure 54 and part (c) of Figure 73 show a modified example in which the shape of each portion of the coupling 143 is formed by ribs. The top surface (inclined surface 149d) comprises the surfaces of a plurality of ribs 149p, and the top surface is divided into a plurality of ribs, and in such a case, 5 the same function can be provided as well. That is, as shown in part (c) of Figure 73, the guide forming portion 149n forming the upstream side top surface (upstream side guide, upstream side inclined portion) 149d2 is a projection (rib) projecting in the radial direction.

[0613] Depending on the characteristics of the material used, it can be used 10 when it is necessary to produce ribs without producing thick portions.

[0614] That is, with each structure of part (a) of Figure 54 to part (d) of Figure 54, each top surface (143d, 147f, 148d1, 148d2, 149d) guides the braking force of the braking engagement member (204, 208) toward the braking force receiving portion 143c regardless of its shape. In other words, each top surface is a guide 15 (inclined portion) for guiding the braking engagement member (204, 208) toward the braking force receiving portion 143c regardless of its shape. At least a part of such a top surface (guide) is formed by the guide forming portion 143n.

[0615] Similar to the top surface, the push-back surface (push-back portion) 143k shown in Figure 52 may have various shapes. For example, the push-back 20 portion (push-back surface) 143k of this modification is a smoothly continuous helical slope, but the push-back portion may be inclined by a plurality of surfaces or steps. For example, the push-back portion 143k may be two surfaces including different inclinations, as in the push-back portion 143k of the Embodiment 1 shown in part (b) of Figure 48 and part (d) of Figure 56. Further, 25 although the push-back surface 143k is ascending, a descending portion may be locally provided.

[0616] The drum coupling 143 may have either the visor portion 143g or the 2026249127   12 Oct 2026 push-back surface (push-back portion) 143k, or may have both of them. As described above, the drum coupling 143 of the Embodiment 1 shown in part (b) of Figure 48, part (b) of Figure 55 and part (d) of Figure 56 has a structure in which not only the visor portion 143g but also the push-back portion 143k is 5 provided. Normally, the drum coupling 143 can block improper entry and access of the braking engagement member (204, 208) by the visor portion 143g, but in the unlikely event that it cannot be blocked, the push-back surface 143k can function to push back the braking engagement members (204, 208) away from the coupling 143. 10

[0617] The drum coupling 143 has a projection shape (push-back portion forming portion, second guide forming portion) 143m that constitutes the pushback surface 143k (see part (b) of Figure 79 and part (c) of Figure 79).

[0618] The engaging portion 143i, the guide forming portion 143n, the projection shape 143m, and the visor portion 143g (see Figure 79) may be 15 referred to as the first, second, third, and fourth shape portions in no particular order correspondence.

[0619] Referring to part (e) of Figure 54 and part (d) of Figure 73, a modified example of the braking force receiving portion (second side surface) will be shown. 20

[0620] The braking force receiving portion 143c described in Embodiment 1 shown in part (a) of Figure 54 and part (a) of Figure 1 and Figures 55 to 57, and the other modified examples shown in Figure 52 and part (b) of Figure 54 to part (d) of Figure 54 has a shape overhanging downstream in the rotational direction. This is because by the braking force receiving portion 143c having a shape 25 overhanging toward the downstream side in the rotational direction, the stability of engagement is increased when it is engaged with the braking engagement members (204, 208). 2026249127   12 Oct 2026

[0621] That is, because of this shape, when the braking force receiving portion 143c engages with the braking engagement member (204, 208), a force is generated so as to attract then toward each other. The braking force receiving portion 143c overhangs toward the downstream side in the rotational direction. 5 Therefore, when the braking force engaging member (204, 208) contacts the braking force receiving portion 143ca force is produced so that the braking force engaging member (204, 208) is attracted inward in the axial direction toward the drum coupling 143 or the photosensitive drum 104. By this, the engaging state between the braking force receiving portion 143c and the braking force engaging 10 member (204, 208) is stabilized, and the engagement is not easily broken.

[0622] As described above, the braking engagement member (204, 208) is structured to be movable in the axial direction relative to the drum drive coupling 180 (see Figures 67 and 68). However, if the braking engagement member (204, 208) moves in the axial direction while the drive transmission unit 203 is driving 15 the drum coupling 143there is a possibility that the engaged state with the braking force receiving portion 143c is broken or becomes unstable. Therefore, it is preferable that the braking force receiving portion 143c has a shape for stabilizing the engagement state with the braking engagement member (204, 208) to suppress the movement of the braking engagement member (204, 208) in the 20 axial direction when the drum coupling 143 is driven.

[0623] However, when the braking force required to be applied to the braking force receiving portion is small, or when the friction coefficient of the braking force receiving portion is high, the engagement between the braking force receiving portion and the braking engagement member (204, 208) tends to be 25 stable. Therefore, it is possible to eliminate the overhang portion of the braking force receiving portion. Such a braking force receiving portion 144t is shown in part (e) of Figure 54 and part (d) of Figure 73. In the modified drum coupling 2026249127   12 Oct 2026 shown in part (e) of Figure 54 Figure and 73 (d), the braking force receiving portion 144c does not overhang toward the downstream side in the rotational direction (arrow A).

[0624] On the other hand, it is also conceivable to devise a device for 5 stabilizing the engagement state with the braking engagement member (204, 208) even for the braking force receiving portion 144c including such a shape.

[0625] In order to stabilize the engagement between the braking force receiving portion 144c and the braking engagement member, It is also conceivable that an elastic member (elastic portion) 144t, for example such as 10 rubber is attached to the braking force receiving portion 144c, or the elastic portion is integrally molded with to the braking force receiving portion 144c. By increasing the friction coefficient of the braking force receiving portion 144t or causing the braking engagement member (204, 208) to bite into the elastic portion of the braking force receiving portion 144t, the engagement with the 15 braking engagement member (204, 208) is less likely to break so that the engagement can be stabilized.

[0626] As a method of increasing the frictional force of the braking force receiving portion 144c, it is conceivable to use an adhesive member (adhesive member) instead of using the elastic member 144t. For example, if a double-20 sided tape (adhesive member) is attached to the surface of the braking force receiving portion 144c, the frictional force between the braking force receiving portion 144c and the braking engagement member (204, 208) increases due to the viscosity of the double-sided tape (adhesive member). In addition, it is conceivable to increase the friction coefficient of the braking force receiving 25 portion 144c by surface-treatment of braking force receiving portion 144c without using the elastic member 144t.

[0627] It is desirable that the helical slope 143d (see Figure 67) for guiding the 2026249127   12 Oct 2026 braking engagement member (204, 208) has a small friction coefficient in order to achieve smooth guiding. Therefore, even when a material having a high coefficient of friction is selected or surface treatment is applied to the braking force receiving portion 144c, it is desirable that such a means is not used for the 5 entire coupling, but the use of such material or such surface treatment is not applied to the helical slope 143d. That is, it is desirable that the friction coefficient of the braking force receiving portion 144c is higher than the friction coefficient of the helical slope 143d.

[0628] The elastic portion 144t may be provided on the braking force 10 receiving portion 143c of the drum coupling 143 as shown in part (a) of Figure 54 to part (d) of Figure 54.

[0629] Next, referring to Figure 101, a preferable arrangement relationship and dimensional relationship of the drum coupling 143 will be described. Figure 101 is a front view of the drum coupling 143 of the Embodiment 1, in 15 which 0 (theta) 11 is a value indicating the dimension of the engaging portion 143i from the driving force receiving portion 143b to the braking force receiving portion 143c by an angle from the axis of the drum coupling. In other words, it is the angle of the region of the downstream inclined portion 143d1.

[0630] Regarding the upper limit of 011, it is desirable that 011 is 90 ° or less, 20 more preferably 80° or less. The angle 011 corresponds to the gap created between the drum drive coupling 180 and the braking engagement members (204, 208) when the drum coupling engages the drive transmission unit 203 (see Figure 64). In order to securely sandwich the driving force receiving portion 143b and the braking force receiving portion 143c between the braking engagement 25 members (204, 208) and the drum drive coupling 180 of the apparatus main assembly, It is desirable that 011 is 90 ° or less, more preferably 80 ° or less.

[0631] On the other hand, regarding the lower limit of 011, if the strength of 2026249127   12 Oct 2026 the engaging portion 143i is increased by using metal as for the material of the engaging portion 143i constituting the driving force receiving portion 143b and the braking force receiving portion 143 c, the 011 can be reduced. Although the details will be described hereinafter, in the modified example of the drum 5 coupling shown in Figure 74, the thickness of the engaging portion 145i corresponding to the engaging portion 143i is made smaller then that in this embodiment, by forming the drum coupling 143 with metal. Considering such a structure, the preferable condition for the lower limit of 011 (Figure 101) is that 011 is 1 °, more preferably 2 ° or still more preferably 8 ° or more. In this 10 embodiment, 011 is set to 30 ° or more, and 011 is set to about 35 °.

[0632] In order to increase the strength of the driving force receiving portion 143b and the braking force receiving portion 143c so that the force can be stably received, the angle 011 corresponding to the thickness of the engaging portion 143i is desirably in a certain range. 15

[0633] When 011 is converted into a length, it becomes the thickness of the engaging portion 143i, that is, the distance measured from the driving force receiving portion 143b to the braking force receiving portion 143c along the rotational direction. The desired range of this distance is 0.3 mm or more, more preferably 1 mm or more. 20

[0634] Further, in Figure 101, 012 indicates a region occupied by the upstream slope (upstream guide, upstream slope) 143d2 by an angle. Regarding the lower limit of 012, it is desirable that the value of 012 is at least half the value of 011, and more preferably the value of 012 is not less than the value of 011. This is because the upstream slope 143d2 needs to have a length in the rotational 25 direction to the extent necessary for guiding the braking engagement member (204, 208) to the braking force receiving portion 143c by the upstream slope 143d2. 2026249127   12 Oct 2026

[0635] As 011 is smaller and the inclination angle of the upstream slope 143d2 is larger, the lower limit of 012 can be made smaller.

[0636] As described above, the lower limit of 012 depends on the value of 011 and the angle of the upstream slope 143d2, but when expressed numerically, 012 5 is ° or more, more preferably 2 ° or still more preferably 8 ° or more, even more preferably 30 ° or more. In this embodiment, 012 is set to be 60 ° or more.

[0637] The upper limit of 012 can be relatively large and can exceed 360 °. However, preferably, 012 is 360 ° or less, more preferably 270 ° or less, and it is 180 ° or less in this example. Specifically, 012 is set to be approximately 67 °. 10

[0638] A structure in which 012 is larger than that of this embodiment will be described hereinafter referring to Figures 102 and 103.

[0639] Angle 013 is the sum of 011 and 012, and corresponds to the angle occupied by the entire helical slope 143d. When 013 is expressed numerically, it is desirable that013 is 2 ° or more, and more preferably 8 ° or more. Further, 15   013 is preferably 360 °or less, and more preferably 270 ° or less. In this embodiment, 013 is set to 180 ° or less. Specifically, 013 set to be approximately 102 °.

[0640] Referring to Figure 74, the shape of another modification of the coupling 143 will be described. 20

[0641] Figure 74 is a perspective view and a front view as seen in two line-of- sight directions of the coupling in the modified example.

[0642] The coupling 143 of this modification includes an engaging portion 145i including a driving force receiving portion 143b and a braking force receiving portion 145b, and a guide forming portion 145n having a helical slope 25   145d. The engaging portion 145i and the guide forming portion 145n correspond to the engaging portion 143i and the guide forming portion 143n of the coupling 143 shown in the Embodiment 1 (see Figure 79), but their shapes are 2026249127   12 Oct 2026 partially different.

[0643] The coupling 143 of this modification includes the visor portion 143g contacting the second braking engagement member 208 (not shown), and the helical slope 145d is formed by a curved surface. This curved surface has a 5 substantially arc shape, and is shaped so as to connect the braking force receiving portion 145c from the inclination start point 143f. In this modified example, since the braking force receiving portion 145c does not have a shape overhanging to the downstream side in the rotational direction, the elastic member (elastic portion) 145t may be attached to the braking force receiving portion 145c as in 10 the case of part (e) of Figure 54.

[0644] The helical slope 145d in this modification (Figure 74) is a top surface corresponding to the upstream slope 143d2 of Embodiment 1 (Figure 57).

[0645] On the other hand, in this modification (Figure 74), the top surface (upper part) 145e (part (b) of Figure 74) of the engaging portion 145i corresponds 15 to the downstream slope 143d1 of the Embodiment 1 (Figure 57), but it is not inclined unlike the downstream side slope 143d1.

[0646] That is, the top surface 145e provided downstream is connected to the top surface (helical slope 145d) provided upstream, but the inclination angles of the surfaces thereof are different at the boundary. The top surface 145e and the 20 helical slope 145d are not smoothly connected.

[0647] Further, since the distance between the driving force receiving portion 143b and the braking force receiving portion 145c is short, the length of the top surface 145e measured along the rotational direction is smaller (shorter) than the length of the downstream slope 143d1 in Figure 57. Further, as described above, 25 the top surface 145e is not inclined. In this modification, it can be considered that the top surface 145e is not used as a guide.

[0648] However, even with such a structure, the helical slope 145d, which is a 2026249127   12 Oct 2026 guide (inclined portion), can guide the braking engagement member (204, 208) toward the braking force receiving portion 145c.

[0649] A plane 145h is adjacent to the upstream of the helical slope 145d, and the helical slope 145d and the plane 145h are connected to each other. The 5 plane 145h can be inclined in the same direction as the helical slope 145d to form a part of the helical slope 145d. Further, the drum coupling of this modification may have the visor portion 143g of the push-back surface 143k described in embodiment 1 or another modification of the Embodiment 1 (see Figures 1, 52, and so on). 10

[0650] Further, regarding the shape of the drum coupling, the shape of the shaft portion 143j shown in Figure 1 can also be selected in view of design reasons. For example, Figure 75 shows a shape of a modified example of the drum coupling. In the example of Figure 75, the diameter of the shaft portion 146j is the same as the diameter of the photosensitive drum 104. The shaft 15 portion 146j is rotatably supported by a driving side cartridge cover member 116 (see Figure 15). The position restriction in the direction of the arrow MB1 can be performed using the shaft end surface 146s, for example. In this manner, the shape of the shaft portion 146j can be appropriately selected depending on the relationship with the peripheral portions and the manufacturing method. 20

[0651] Another modification of the drum coupling 143 is shown in part (b) of Figure 76, part (c) of Figure 76, part (a) of Figure 78, part (b) of Figure 78, part (c) of Figure 78, and part (d) of Figure 78. These Figures show drum couplings in which two coupling portions 143s and 143r have different shapes. Part (b) and (c) Figure 76 are development views of the coupling 143, and in part (c) of 25 Figure 76, the drum drive coupling 180 and the braking engagement member 208 provided in the device main assembly side are also shown in the development view. Part (a) of Figure 78 and part (b) of Figure 78 are perspective views of 2026249127   12 Oct 2026 the drum coupling 143. Further, part (c) of Figure 78 and part (d) of Figure 78 show the engagement state of the braking engagement member (204, 208) and the drum drive coupling with respect to the drum coupling 143.

[0652] In the coupling 143 shown in these Figures, the engaging portion 143i 5 of one coupling portion 143s is not provided with the braking force receiving portion 143c, but includes only the driving force receiving portion 143b. That is, the side surface 143y provided on the engaging portion 143i of the coupling portion 143s does not engage with the braking engagement member (204, 208). On the other hand, the engaging portion 143i of the other coupling portion 143r is 10 provided only the braking force receiving portion 143c and is not provided with the driving force receiving portion 143b. The side surface 143x of the engaging portion 143i of the coupling portion 143r does not engage with the drum drive coupling 180.

[0653] An example of another asymmetrical coupling 143 is shown in part (d) 15 of Figure 76. This coupling portion 143s is an example in which the coupling portion 143s does not have any side surface corresponding to the driving force receiving portion 143c.

[0654] The modified example of the coupling 143 shown in part (b) of Figure 76, part (c) of Figure 76, part (a) of Figure 78, part (b) of Figure 78, part (c) of 20 Figure 78, and Figure 7 is a(d) receives a driving force at only one place and receives the braking force at only one place. Therefore, in order for the drum coupling to stably receive the driving force and the braking force, it is preferable to improve the fitting accuracy between the circular hole portion 143a and the positioning boss 180i of the drum drive coupling 180 (see Figure 51). That is, it 25 is preferable to reduce the gap produced between them, thus improving, the positional accuracy of the drum coupling 143 relative to the drive transmission unit 203, to stably and surely engage the drive transmission unit 203 and the 2026249127   12 Oct 2026 drum coupling 143.

[0655] Further, Figure 77 shows another modification of the drum coupling including one driving force receiving portion and one braking force receiving portion. The drum coupling 143 shown in Figure 77 has only one upstream side 5 slope 143d2, only one downstream side slope 143d1, only one visor portion 143g, only one driving force receiving portion 143b, only one braking force receiving portion 143c, and only one extrusion surface 143k. Part (a) of Figure 77 is a perspective view of the drum coupling, and part (b) of Figure 77 is a front view thereof. 10

[0656] In the modified example of the drum coupling 143 as shown in Figure 77, arbitrary portions of the slope 143d, the visor portion 143g, the driving force receiving portion 143b, the braking force receiving portion 143c, and the extrusion surface 143k may be placed at a 180 ° position or positions (axisymmetric). 15

[0657] For example, as shown in Figure 96, the drum coupling 143 visor portion 143g shown in Figure 77 may be moved to the 180 ° symmetric region S143g, or the extrusion surface 143k may be moved to the symmetric region S143k.

[0658] This is because the drum drive coupling 180 and the braking 20 engagement members (204, 208) both have 180 ° symmetrical shape.

[0659] Therefore, regardless of which one of the two180 ° symmetrical places is the place where one helical slope 143d is disposed, the slope 143d can act on the entire braking engagement member (204, 208). Similarly, the extrusion surface 143k may be placed at either of the two places which are ° symmetrical 25 with respect to each other. The same applies not only to the visor portion 143g and the extrusion surface 143 k, but also to the braking force receiving portion 143 c. 2026249127   12 Oct 2026

[0660] Further, the drum drive coupling 180 can engage with the drive force receiving portion 143b regardless of whether the drive force receiving portion 143b is placed at either of two 180 ° symmetrical positions.

[0661] The drum drive coupling 180 has two drive transmission surfaces 180d, 5 but the two drive transmission surfaces 180d move integrally (part (a) of Figure 45). Further, the braking engagement members (204, 208) have two coupling engaging portions 204b and two each, and all of these coupling engaging portions move integrally (see part (b) of Figure 45).

[0662] As another modification in which the shape of the drum coupling 143 10 is made asymmetrical as described above, there is also a follow structure. That is, one coupling portion 143s has an engaging portion 143i but does not have a guide forming portion 143n, and the other coupling portion 143r has a guide forming portion 143n but does not have an engaging portion 143i. Such a structure is conceivable. 15

[0663] Examples of such a structure are shown in parts (a) and (b) of Figure 97. Part (a) of Figure 97 is a perspective view of a modified example of the drum coupling, and part (b) of Figure 97 is a front view thereof.

[0664] In the modified example of the drum coupling shown in these Figures, the guide forming portion 343n and the engaging portion 343i have one. The 20 guide forming portion 343n forms a helical slope (guide, top surface, inclined portion) 343d2. The engaging portion 343i forms a driving force receiving portion 343b and a helical slope (guide, top surface, inclined portion) 343d1. The guide forming portion 343n and the engaging portion 343i are located on opposite sides of the axis L. Further, in this modification, the braking force 25 receiving portion 343b is not arranged at the engaging portion 343i, but is arranged at the end portion downstream of the guide forming portion 343n in the rotational direction. That is, the engaging portion 343i engages with the driving 2026249127   12 Oct 2026 force applying member (drum drive coupling) 180, but does not engage with the braking force applying member (braking engagement members 204, 208).

[0665] Part (a) of Figures 99, (b), and (c) show the engagement process of the drum coupling and the braking engagement member (204, 208) of this modified 5 example in this order. For the sake of explanation, the drum drive coupling 180 of the drive transmission unit 203 is not shown.

[0666] As shown in part (a) of Figure 99, when the second braking engagement member 208 comes into co...

Claims

1. A cartridge detachably mountable to a main assembly of an image forming apparatus, the cartridge comprising:a photosensitive drum;a casing having a first end portion and a second end portion opposite from the first end portion in an axial direction of the photosensitive drum, the casing rotatably supporting the photosensitive drum; anda coupling operatively connected to the photosensitive drum so as to be capable of transmitting a driving force toward the photosensitive drum, the coupling being positioned adjacent to the first end portion of the casing,wherein the coupling includes:a main body, anda movable portion movable relative to the main body of the coupling between a first position and a second position,wherein the movable portion is closer to the second end portion of the casing in the axial direction of the photosensitive drum when the movable portion is in the second position than when the movable portion is in the first position,wherein the coupling further includes a projection configured to move in the circumferential direction of the coupling and downstream in a rotational movement direction of the coupling by not less than 20° relative to the main body of the coupling in response to movement of the movable portion from the first position to the second position,the projection projects so as to be away from an axis of the coupling, andthe projection has an acting portion configured to abut on a braking force applying member provided in the main assembly for applying a braking force to the coupling and move the braking force applying member downstream in the rotational movement direction of the coupling relative to a driving force applying member provided in the main assembly for applying the driving force to the coupling.

2. A cartridge according to Claim 1, wherein the coupling includes two of the projections which are provided at diametrically opposite positions with respect to an axis of the coupling, and the two projections are configured to move in response to the movement of the movable portion.

3. A cartridge according to Claim 1 or 2, wherein the movable portion is disposed on or adjacent2026249127   12 Oct 2026to the axis of the coupling.

4. A cartridge according to any one of Claims 1 - 3, wherein the projection is positioned outside the main body of the coupling and exposed outside the cartridge so that the projection can abut on the braking force applying member.

5. A cartridge according to any one of Claims 1 - 4, wherein the projection is positioned outside of the movable portion in a radial direction of the coupling.

6. A cartridge according to any one of Claims 1 - 5, wherein the movable portion is configured to move from the first position to the second position by being pressed by a pressing portion provided on the driving force applying member.

7. A cartridge according to any one of Claims 1 - 6, wherein the projection is movable by not less than 60° about the axis of the coupling.

8. A cartridge according to any one of Claims 1 - 7, wherein the projection is movable by not less than 90° about the axis of the coupling.

9. A cartridge according to any one of Claims 1 - 8, wherein an angle by which the projection moves about the axis of the coupling is not more than 180°.

10. A cartridge according to any one of Claims 1 - 9, wherein an angle by which the projection moves about the axis of the coupling is not more than 150°.

11. A cartridge according to any one of Claims 1 - 10, wherein the coupling is provided with a visor portion arranged in a radial direction of the coupling,the visor portion being disposed more remote from the second end portion of the casing in the axial direction of the coupling than the projection.

12. A cartridge according to Claim 11, wherein the coupling has a cut away portion in which neither of the visor portion and the projection is present in the circumferential direction of the coupling.2026249127   12 Oct 202613. A cartridge according to any one of Claims 1 - 12, wherein the coupling includes a first movable member provided with the movable portion, and a second movable member provided with the projection and interrelated with the first movable member.

14. A cartridge according to Claim 13, wherein the first movable member is a translational movable member capable of a translational movement in the axial direction of the coupling relative to the main body of the coupling,and wherein the second movable member is a rotational movable member movable in the circumferential direction of the coupling about the axis of the coupling relative to the first movable member and the main body of the coupling.

15. A cartridge according to Claim 13 or 14, wherein when the movable portion is in the second position, at least a part of the first movable member is inside the main body of the coupling.

16. A cartridge according to Claims 13 - 15, wherein the coupling includes a cam having the first movable member and the second movable member.

17. A cartridge according to any one of Claims 1 - 16, wherein the projection is configured to receive the driving force from outside of the cartridge by abutting on the driving force applying member.

18. A cartridge according to any one of Claims 1 - 17, wherein the projection has a driving force receiving portion at a surface on an upstream side in a rotational direction of the coupling for receiving the driving force.

19. A cartridge according to any one of Claims 1 - 18, wherein the projection is configured to enter between the driving force applying member and the braking force applying member.

20. A cartridge according to any one of Claims 1 - 19, wherein the projection is configured to receive the braking force from the braking force applying member.2026249127   12 Oct 202621. A cartridge according to any one of Claims 1 - 20, wherein the projection has a braking force receiving portion at a surface on a downstream side in the rotating direction for receiving the braking force.Canon Kabushiki KaishaPatent Attorneys for the Applicant SPRUSON & FERGUSON

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