Cartridge

Abstract

This cartridge has a frame body, a photosensitive drum, and a rack. The photosensitive drum is supported by the frame body and can rotate around an axis. The rack includes one or more teeth configured to be at least partially exposed to face the axis of the photosensitive drum. The rack is positioned on the side of the cartridge in the axial direction of the photosensitive drum.

Description

cartridge

[0001] The present invention relates to a cartridge and an image forming apparatus using the cartridge.

[0002] Here, a cartridge is a device that can be attached to and detached from the main body of an image forming apparatus. One example is a process cartridge. A process cartridge is a cartridge that integrates a photosensitive member and a process means that acts on the photosensitive member, and is detachably attached to the main body of an electrophotographic image forming apparatus.

[0003] For example, a cartridge may be used in which a photosensitive member and at least one of a developing means, a charging means, and a cleaning means as the process means are integrated together. The image forming apparatus in the present application is an electrophotographic image forming apparatus that forms an image on a recording medium using an electrophotographic image forming method.

[0004] Examples of electrophotographic image forming apparatuses include electrophotographic copying machines, electrophotographic printers (LED printers, laser beam printers, etc.), facsimile machines, and word processors.

[0005] In an electrophotographic image forming apparatus (hereinafter simply referred to as an "image forming apparatus"), an electrophotographic photosensitive member, generally drum-shaped, serving as an image carrier, i.e., a photosensitive drum (electrophotographic photosensitive drum), is uniformly charged. Next, an electrostatic latent image (electrostatic image) is formed on the photosensitive drum by selectively exposing the charged photosensitive drum to light. The electrostatic latent image formed on the photosensitive drum is then developed into a toner image using toner as a developer. The toner image formed on the photosensitive drum is then transferred to a recording material such as recording paper or a plastic sheet, and the toner image transferred to the recording material is fixed to the recording material by applying heat and pressure, thereby recording an image.

[0006] Such image forming apparatuses generally require toner replenishment and maintenance of various process means. To facilitate this toner replenishment and maintenance, a process cartridge has been put into practical use, in which the photosensitive drum, charging means, developing means, cleaning means, etc. are all housed within a frame and integrated into a cartridge that can be detachably attached to the image forming apparatus main body.

[0007] This process cartridge system allows users to perform some of the maintenance of the device themselves, without relying on service personnel in charge of after-sales service. This significantly improves the operability of the device, making it possible to provide an image forming device with excellent usability. For this reason, this process cartridge system is widely used in image forming devices.

[0008] Furthermore, as the above-mentioned image forming apparatus, as described in Japanese Patent Application Laid-Open No. 8-328449 (see Figure 16), a commonly known apparatus has a coupling at its tip that transmits drive from the image forming apparatus main body to the process cartridge, and a drive transmission member that is biased toward the process cartridge by a spring.

[0009] When the door of the image forming apparatus main body is closed, the drive transmission member of this image forming apparatus is pressed by a spring and moves toward the process cartridge. This causes the drive transmission member to engage (couple) with the coupling of the process cartridge, enabling drive transmission to the process cartridge. Furthermore, when the door of the image forming apparatus main body is opened, a cam causes the drive transmission member to move in a direction away from the process cartridge against the spring. This causes the drive transmission member to disengage (coupling) from the coupling of the process cartridge, allowing the process cartridge to be removed from the image forming apparatus main body.

[0010] An example of an embodiment of the present invention is a cartridge having a frame body, a photosensitive drum supported by the frame body and rotatable about an axis, and a rack located on a side of the cartridge in the axial direction of the photosensitive drum, the rack having one or more teeth configured to be at least partially exposed so as to face the axis of the photosensitive drum.

[0011] Another example of an embodiment is a cartridge having a frame body, a photosensitive drum supported by the frame body and rotatable around an axis, and an elastic body having a surface configured to be at least partially exposed so as to face the axis of the photosensitive drum and positioned on a side of the cartridge in the axial direction of the photosensitive drum.

[0012] Another example of an embodiment is a cartridge having a frame body, a photosensitive drum supported by the frame body and rotatable about an axis, and a friction force applying portion having a surface configured to be at least partially exposed so as to face the axis of the photosensitive drum and located on a side of the cartridge in the axial direction of the photosensitive drum.

[0013] Another example of an embodiment is a cartridge having a frame body, a photosensitive drum supported by the frame body and rotatable around an axis, and a tacky member located on a side of the cartridge in the axial direction of the photosensitive drum, the tacky member having a surface configured to be at least partially exposed so as to face the axis of the photosensitive drum.

[0014] Another example of an embodiment is a cartridge having a frame body, a photosensitive drum supported by the frame body and rotatable around its own axis, one or more movable teeth configured to be at least partially exposed to face the axis of the photosensitive drum and located on a side of the cartridge in the axial direction of the photosensitive drum, and a lock configured to prevent movement of the one or more teeth.

[0015] Another example of an embodiment is a cartridge having a frame body, a photosensitive drum supported by the frame body and rotatable about an axis, and a rotatable missing-tooth gear located on the side of the cartridge and having one or more teeth configured to be at least partially exposed so as to face the axis of the photosensitive drum.

[0016] Another example of an embodiment is a cartridge comprising: a frame; a photosensitive drum supported by the frame and rotatable about an axis, the photosensitive drum having a first end and a second end opposite the first end; one or more movable teeth located on a side of the cartridge in the axial direction of the photosensitive drum and configured to be at least partially exposed toward the axis of the photosensitive drum; and a spring that biases the one or more teeth, wherein when viewed along the axis of the photosensitive drum with the downstream direction of rotation of the photosensitive drum being the positive direction of the angle, a line extending from the axis of the photosensitive drum to pass through any of the one or more teeth forms an angle of between -75° and 50°, or between 130° and 190°, with respect to a line extending from the axis of the photosensitive drum to pass through the axis of the developing roller.

[0017] Another example of an embodiment is a cartridge comprising: a frame; a photosensitive drum supported by the frame and rotatable around an axis; one or more teeth located on a side of the cartridge in the axial direction of the photosensitive drum and configured to be at least partially exposed toward the axis of the photosensitive drum; and a movable lever provided with the one or more teeth, wherein when viewed along the axis of the photosensitive drum with the downstream direction of rotation of the photosensitive drum being the positive direction of the angle, a line extending from the axis of the photosensitive drum to pass through any of the one or more teeth can be positioned such that with respect to a line extending from the axis of the photosensitive drum to pass through the axis of the developing roller, the one or more teeth can be positioned such that an angle of -75° or more and 50° or less, or 130° or more and 190° or less, forms with respect to a line extending from the axis of the photosensitive drum to pass through the axis of the developing roller.

[0018] Another example of an embodiment is a cartridge having: a frame; a photosensitive drum supported by the frame and rotatable about an axis, the photosensitive drum having a first end and a second end opposite the first end; and a rotatable gear located on a side of the cartridge in the axial direction of the photosensitive drum, the gear having one or more teeth configured to be at least partially exposed toward the axis of the photosensitive drum, the gear being movable in the axial direction of the photosensitive drum.

[0019] Another example of an embodiment is a cartridge comprising: a frame; a photosensitive drum supported by the frame and rotatable around an axis; and a rotatable gear located on a side of the cartridge in the axial direction of the photosensitive drum and having one or more teeth configured to be at least partially exposed toward the axis of the photosensitive drum, wherein one of the frame and the gear has a hole, and the other has a shaft that fits into the hole, and the gear is movable in a direction perpendicular to its axis due to a gap between the hole and the shaft.

[0020] Another example of an embodiment is a cartridge having a frame body, a photosensitive drum supported by the frame body and rotatable around an axis, and a rotatable belt having a surface configured to be at least partially exposed to the outside so as to face the axis of the photosensitive drum, and located on a side of the cartridge in the axial direction of the photosensitive drum.

[0021] According to some preferred embodiments of the present invention, the above-mentioned prior art can be further developed.

[0022] 1A and 1B are explanatory diagrams of a drive transmission portion of a process cartridge according to a first embodiment.

[0023] FIG. 2 is a cross-sectional view of the main assembly of the electrophotographic image forming apparatus and the process cartridge according to the first embodiment.

[0024] FIG. 3 is a cross-sectional view of the process cartridge according to the first embodiment.

[0025] FIG. 4 is an exploded perspective view of the process cartridge according to the first embodiment.

[0026] FIG. 5 is an exploded perspective view of the process cartridge according to the first embodiment.

[0027] 6A, 6B, and 6C are explanatory diagrams of the link portion of the electrophotographic image forming apparatus according to the first embodiment.

[0028] 7A and 7B are explanatory diagrams of the link portion of the electrophotographic image forming apparatus according to the first embodiment.

[0029] 8A and 8B are cross-sectional views of the guide portion of the electrophotographic image forming apparatus according to the first embodiment.

[0030] FIG. 9 is an explanatory diagram of the drive train portion of the electrophotographic image forming apparatus according to the first embodiment.

[0031] 10A and 10B are explanatory diagrams of a longitudinal positioning portion of an electrophotographic image forming apparatus according to a first embodiment.

[0032] 11A and 11B are cross-sectional views of the positioning portion of the electrophotographic image forming apparatus according to the first embodiment.

[0033] 12A and 12B are explanatory diagrams of the link portion of the electrophotographic image forming apparatus according to the first embodiment.

[0034] 13A and 13B are perspective views of the drive transmission portion of the electrophotographic image forming apparatus according to the first embodiment.

[0035] FIG. 14 is a perspective view of a drive transmission portion of the electrophotographic image forming apparatus according to the first embodiment.

[0036] FIG. 15 is a cross-sectional view of a drive transmission portion of an electrophotographic image forming apparatus according to the first embodiment.

[0037] FIG. 16 is an explanatory diagram of the drive train of the process cartridge according to the first embodiment.

[0038] FIG. 17 is a cross-sectional view of the drive transmission portion of the electrophotographic image forming apparatus according to the first embodiment.

[0039] 18A and 18B are cross-sectional views of the drive transmission portion of the electrophotographic image forming apparatus according to the first embodiment.

[0040] 19A and 19B are cross-sectional views of the drive transmission portion of the electrophotographic image forming apparatus according to the first embodiment.

[0041] FIG. 20 is a cross-sectional view of the drive transmission portion of the electrophotographic image forming apparatus according to the first embodiment.

[0042] FIG. 21 is a cross-sectional view of the drive transmission portion of the electrophotographic image forming apparatus according to the first embodiment.

[0043] FIG. 22 is an explanatory diagram of the drive train of the process cartridge according to the first embodiment.

[0044] FIG. 23 is a perspective view of a process cartridge according to the second embodiment.

[0045] 24A and 24B are explanatory diagrams of the drive train of the process cartridge according to the second embodiment.

[0046] 25A and 25B are explanatory diagrams of the rack gear mechanism of the process cartridge according to the second embodiment.

[0047] 26A, 26B, and 26C are explanatory diagrams of the rack gear mechanism of the process cartridge according to the second embodiment.

[0048] 27A, 27B, and 27C are explanatory diagrams of the rack gear mechanism of the process cartridge according to the second embodiment.

[0049] 28(a) and 28(b) are explanatory diagrams of the rack gear mechanism of the process cartridge according to the second embodiment.

[0050] 29A and 29B are explanatory diagrams of the arrangement of the rack gear mechanism of the process cartridge according to the second embodiment.

[0051] 30A, 30B, 30C, and 30D are cross-sectional views showing the operation of the rack gear mechanism of the process cartridge according to the second embodiment.

[0052] 31A and 31B are explanatory diagrams of a drive transmission section of an electrophotographic image forming apparatus according to a second embodiment.

[0053] 32(a), (b) and (c) are cross-sectional views of the drive transmission portion of the electrophotographic image forming apparatus according to the second embodiment.

[0054] 33A and 33B are cross-sectional views of an electrophotographic image forming apparatus showing the process of mounting a process cartridge according to the second embodiment.

[0055] 34A and 34B are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the second embodiment.

[0056] 35(a), (b) and (c) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the second embodiment.

[0057] 36A and 36B are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the second embodiment.

[0058] 37A, 37B, 37C, and 37D are cross-sectional views of the electrophotographic image forming apparatus showing the process of removing the process cartridge according to the second embodiment.

[0059] FIG. 38 is a cross-sectional view of an electrophotographic image forming apparatus according to the second embodiment.

[0060] 39(a) and (b) are explanatory diagrams relating to a first modified example of the second embodiment.

[0061] 40(a) and (b) are explanatory diagrams relating to a second modified example of the second embodiment.

[0062] FIG. 41 is a perspective view of a process cartridge according to the third embodiment.

[0063] 42(a) and 42(b) are explanatory diagrams showing the arrangement of frictional force applying surfaces of the process cartridge according to the third embodiment.

[0064] 43(a) and 43(b) are explanatory diagrams of the drive transmission section of the electrophotographic image forming apparatus according to the third embodiment.

[0065] 44(a) and 44(b) are cross-sectional views of an electrophotographic image forming apparatus showing the process of mounting a process cartridge according to the third embodiment.

[0066] 45(a) and 45(b) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the third embodiment.

[0067] 46(a) and 46(b) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the third embodiment.

[0068] 47A and 47B are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the third embodiment.

[0069] 48(a), (b) and (c) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the third embodiment.

[0070] 49(a) and 49(b) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the third embodiment.

[0071] 50(a) and 50(b) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the third embodiment.

[0072] Figure 51(a) is a diagram explaining a method for measuring the coefficient of friction, and Figure 51(b) is a diagram explaining a method for measuring the degree of elasticity.

[0073] FIG. 52 is a perspective view of a process cartridge according to the fourth embodiment.

[0074] Figures 53(a) and (b) are explanatory diagrams of the arrangement of the elastic rotation members of the process cartridge according to the fourth embodiment.

[0075] 54(a) and 54(b) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the fourth embodiment.

[0076] FIG. 55 is a sectional view showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the fourth embodiment.

[0077] FIG. 56 is a perspective view of a process cartridge according to the fifth embodiment.

[0078] Figures 57(a) and (b) are explanatory diagrams of the gear mechanism with missing teeth of the process cartridge according to the fifth embodiment.

[0079] Figures 58(a) and (b) are explanatory diagrams of the gear mechanism with missing teeth of the process cartridge according to the fifth embodiment.

[0080] Figures 59(a), (b), and (c) are explanatory diagrams of the partially toothed gear mechanism of the process cartridge according to the fifth embodiment.

[0081] Figures 60(a) and (b) are explanatory diagrams showing the arrangement of the gear mechanism having missing teeth of the process cartridge according to the fifth embodiment.

[0082] Figures 61(a) and (b) are cross-sectional views showing the operation of the gear mechanism having missing teeth of the process cartridge according to the fifth embodiment.

[0083] Figures 62(a) and (b) are cross-sectional views of an electrophotographic image forming apparatus showing the process of mounting a process cartridge according to the fifth embodiment.

[0084] 63(a) and 63(b) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the fifth embodiment.

[0085] 64(a) and 64(b) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the fifth embodiment.

[0086] Figures 65(a), (b) and (c) are cross-sectional views of the electrophotographic image forming apparatus showing the process of removing the process cartridge according to the fifth embodiment.

[0087] 66(a) and 66(b) are explanatory diagrams relating to a first modified example of the fifth embodiment.

[0088] Figure 67 is a perspective view of a process cartridge according to the sixth embodiment.

[0089] Figures 68(a) and (b) are explanatory diagrams of the rotary rack gear mechanism of the process cartridge according to the sixth embodiment.

[0090] Figures 69(a) and (b) are explanatory diagrams of the rotary rack gear mechanism of the process cartridge according to the sixth embodiment.

[0091] Figures 70(a) and (b) are explanatory diagrams showing the operation of the rotary rack gear mechanism of the process cartridge according to the sixth embodiment.

[0092] 71(a), (b), (c) and (d) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the sixth embodiment.

[0093] 72(a), (b), (c) and (d) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the sixth embodiment.

[0094] 73(a) and (b) are explanatory diagrams relating to a first modified example of the sixth embodiment.

[0095] Figure 74 is a perspective view of a process cartridge according to the seventh embodiment.

[0096] Figures 75(a) and (b) are explanatory diagrams of the biasing mechanism of the process cartridge according to the seventh embodiment.

[0097] Figures 76(a) and (b) are explanatory diagrams of the arrangement of the urging mechanism of the process cartridge according to the seventh embodiment.

[0098] Figures 77(a) and (b) are cross-sectional views showing the operation of the urging mechanism of the process cartridge according to the seventh embodiment.

[0099] Figures 78(a) and (b) are cross-sectional views of an electrophotographic image forming apparatus showing the process of mounting a process cartridge according to the seventh embodiment.

[0100] 79(a) and 79(b) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the seventh embodiment.

[0101] 80(a), (b) and (c) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the seventh embodiment.

[0102] FIG. 81 is a sectional view showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the seventh embodiment.

[0103] 82(a) and 82(b) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the seventh embodiment.

[0104] FIG. 83 is a perspective view of a process cartridge according to a first modified example of the seventh embodiment.

[0105] FIG. 84 is a distribution diagram of a process cartridge according to a first modified example of the seventh embodiment.

[0106] FIG. 85 is an explanatory diagram of the locking of the process cartridge according to the first modified example of the seventh embodiment.

[0107] Figures 86(a) and (b) are explanatory diagrams of the locking of the process cartridge according to the first modified example of the seventh embodiment.

[0108] Figures 87(a) and (b) are explanatory views of the protruding member of the process cartridge according to the first modified example of the seventh embodiment.

[0109] Figures 88(a) and (b) are explanatory diagrams of the locking of the process cartridge according to the first modified example of the seventh embodiment.

[0110] Figures 89(a) and (b) are explanatory views of the protruding member of the process cartridge according to the first modified example of the seventh embodiment.

[0111] Figures 90(a), (b), (c), and (d) are explanatory diagrams of the locking operation of the process cartridge according to the first modified example of the seventh embodiment.

[0112] 91(a) and 91(b) are cross-sectional views showing the operation of opening and closing the door of an electrophotographic image forming apparatus according to a first modified example of the seventh embodiment.

[0113] 92(a) to 92(l) are explanatory diagrams of the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the first modified example of the seventh embodiment.

[0114] 93(a) and 93(b) are explanatory diagrams of the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the first modified example of the seventh embodiment.

[0115] FIG. 94 is a perspective view of a process cartridge according to a second modified example of the seventh embodiment.

[0116] FIG. 95 is an explanatory view of an engaging mechanism of a process cartridge according to a second modified example of the seventh embodiment.

[0117] Figures 96(a) and (b) are explanatory views of the engagement mechanism of a process cartridge according to a second modified example of the seventh embodiment.

[0118] Figures 97(a) to (f) are explanatory views of the engagement mechanism of a process cartridge according to a second modified example of the seventh embodiment.

[0119] 98(a) and 98(b) are cross-sectional views showing the operation of the drive transmission portion of an electrophotographic image forming apparatus according to a second modified example of the seventh embodiment.

[0120] Figures 99(a) to (f) are explanatory views of the engagement mechanism of a process cartridge according to a second modified example of the seventh embodiment.

[0121] 100(a) and 100(b) are explanatory diagrams of the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the second modified example of the seventh embodiment.

[0122] FIG. 101 is an explanatory diagram of a drive train of a process cartridge according to a second modified example of the seventh embodiment.

[0123] FIG. 102 is a perspective view of a process cartridge according to the eighth embodiment.

[0124] FIG. 103 is an explanatory diagram of the engagement mechanism of the process cartridge according to the eighth embodiment.

[0125] Figures 104(a) and (b) are explanatory diagrams of the engagement mechanism of the process cartridge according to the eighth embodiment.

[0126] 105(a) and 105(b) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the eighth embodiment.

[0127] FIG. 106 is an explanatory view of an engaging mechanism of a process cartridge according to a first modified example of the eighth embodiment.

[0128] 107(a) and 107(b) are cross-sectional views showing the operation of the drive transmission portion of an electrophotographic image forming apparatus according to a first modified example of the eighth embodiment.

[0129] FIG. 108 is an explanatory view of an engaging mechanism of a process cartridge according to a second modified example of the eighth embodiment.

[0130] FIG. 109 is a sectional view showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the second modified example of the eighth embodiment.

[0131] FIG. 110 is an explanatory view of an engaging mechanism of a process cartridge according to a third modified example of the eighth embodiment.

[0132] Figure 111 is a perspective view of a process cartridge according to the ninth embodiment.

[0133] Figures 112(a) and (b) are explanatory diagrams of the load applying mechanism of the process cartridge according to the ninth embodiment.

[0134] Figures 113(a) and (b) are explanatory diagrams of the load applying mechanism of the process cartridge according to the ninth embodiment.

[0135] 114(a) and 114(b) are cross-sectional views showing the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the ninth embodiment.

[0136] 115(a), (b), and (c) are explanatory diagrams of the operation of the drive transmission portion of the electrophotographic image forming apparatus according to the ninth embodiment.

[0137] 116(a), (b), and (c) are explanatory diagrams relating to a first modified example of the ninth embodiment.

[0138] 117(a), (b), and (c) are explanatory diagrams relating to a second modified example of the ninth embodiment.

[0139] Figure 118(a) is a perspective view of the cartridge, and Figure 118(b) is an exploded perspective view of the cartridge.

[0140] Figure 119(a) is a side view of the cartridge, and Figure 119(b) is a cross-sectional view of the cartridge.

[0141] FIG. 120 is an explanatory diagram of the drive transmission member.

[0142] FIG. 121 is an explanatory diagram of the cartridge and the drive transmission member.

[0143] FIG. 122 is an explanatory diagram of the drive transmission member.

[0144] FIG. 123(a) is an explanatory diagram of the drive transmission member, and FIG. 123(b) is an explanatory diagram of the cartridge and the drive transmission member.

[0145] FIG. 124(a) is an explanatory diagram of the drive transmission member, and FIG. 124(b) is an explanatory diagram of the cartridge and the drive transmission member.

[0146] FIG. 125(a) is an explanatory diagram of the drive transmission member, and FIG. 125(b) is an explanatory diagram of the cartridge and the drive transmission member.

[0147] FIG. 126(a) is an explanatory diagram of the drive transmission member, and FIG. 126(b) is an explanatory diagram of the cartridge and the drive transmission member.

[0148] FIG. 127(a) is an explanatory diagram of the drive transmission member, and FIG. 127(b) is an explanatory diagram of the cartridge and the drive transmission member.

[0149] Figure 128(a) is a perspective view of the cartridge, and Figure 128(b) is a side view of the cartridge.

[0150] Figure 129(a) is a perspective view of the cartridge, and Figure 129(b) is a perspective view of the cartridge.

[0151] Figure 130(a) is an exploded perspective view of the cartridge, and Figure 130(b) is an exploded perspective view of the cartridge.

[0152] 131(a) and (b) show the control member.

[0153] Figures 132(a) and (b) are side views of the cartridge.

[0154] FIG. 133(a) is a cross-sectional view of the cartridge for explaining the positional relationship of the control members, and FIG. 133(b) is a diagram showing the control members.

[0155] Figure 134(a) is a side view of the cartridge, and Figure 134(b) is a front view of the cartridge and the drive transmission member.

[0156] FIG. 135 is a side view of the cartridge.

[0157] FIG. 136 is a side view of the cartridge.

[0158] FIG. 137 is a side view of the cartridge.

[0159] FIG. 138 is a side view of the cartridge.

[0160] FIG. 139 is a side view of the cartridge.

[0161] Figures 140(a) and (b) are side views of the cartridge.

[0162] FIG. 141 is a cross-sectional view of the main body and cartridge of the image forming apparatus.

[0163] FIG. 142 is a cross-sectional view of the cartridge.

[0164] 143(a) and 143(b) are perspective views of the image forming apparatus with the door open and closed.

[0165] FIG. 144 is a cross-sectional view of the drive transmission member when the door is closed.

[0166] FIG. 145 is a perspective view of the vicinity of the cylindrical cam when the door is open.

[0167] Figures 146(a) and (b) are cross-sectional views of the image forming apparatus when the cartridge is mounted.

[0168] Figure 147 is a perspective view of the drive side of the cartridge.

[0169] Figures 148(a) and (b) are cross-sectional views of the image forming apparatus showing the cartridge pressing portion and the positioning portion.

[0170] FIG. 149 is a perspective view of the drive transmission member.

[0171] Figure 150 is a cross-sectional view showing the movement of the drive transmission member in the thrust direction when the coupling is engaged.

[0172] Figure 151 is a cross-sectional view showing the periphery of the drive transmission member when the coupling is engaged.

[0173] FIG. 152 is a perspective view showing the support structure of the bearing of the drive transmission member on the drive side.

[0174] 153(a) and 153(b) are cross-sectional views showing the attitude of the drive transmission member.

[0175] FIG. 154 is a cross-sectional view showing the attitude of the drive transmission member when the door is open.

[0176] Figures 155(a) and (b) are perspective views showing the control member of the cartridge.

[0177] Figure 156 is a cross-sectional view showing the tilting operation of the drive transmission member when the cartridge is mounted.

[0178] 157(a) and 157(b) are perspective views showing the drive transmission member and the cover portion.

[0179] Figure 158 is a cross-sectional view showing the operation of the control member when the cartridge is mounted and removed.

[0180] FIG. 159 is a top view of the cartridge.

[0181] FIG. 160 is a side view of the cartridge.

[0182] Figure 161 is a cross-sectional view of the cartridge.

[0183] FIG. 162 is a top view of the cartridge.

[0184] Figure 163 is a perspective view of the cartridge.

[0185] Figure 164 is a cross-sectional view of the cartridge and the main body of the image forming apparatus.

[0186] FIG. 165 is a cross-sectional view of the cartridge.

[0187] Figure 166 is a perspective view of the cartridge.

[0188] Figure 167 is a perspective view of the cartridge.

[0189] Figure 168 is a cross-sectional view of some parts as seen from the non-drive side.

[0190] FIG. 169 shows the arrangement of the rack gear.

[0191] FIG. 170 shows the arrangement of the rack gear.

[0192] Figure 171 is a side view of the drive side of the cartridge.

[0193] Figures 172(a) and (b) are side views of the gear portion and the process cartridge as seen from the drive side.

[0194] FIG. 173 is a side view of the cartridge as seen from the driving side.

[0195] Figures 174(a) and (b) are cross-sectional views of the apparatus main body and cartridge ZB.

[0196] FIG. 175 is a cross-sectional view of some components as seen from the non-drive side.

[0197] FIG. 176 is a side view of the drive transmission member.

[0198] Figure 177 is a cross-sectional view of the device main body and cartridge.

[0199] Figure 178 is a cross-sectional view of the device main body and cartridge.

[0200] Figure 179 is a side view of the cartridge as seen from the drive side.

[0201] Figures 180(a) and (b) are cross-sectional views of some parts as seen from the non-drive side.

[0202] FIG. 181 is a cross-sectional view of the apparatus main body and cartridge ZB.

[0203] FIG. 182 is an enlarged cross-sectional view of one tooth of the gear portion.

[0204] Figure 183 is a cross-sectional view of the device body and the cartridge.

[0205] Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

[0206] The direction of the rotation axis of the electrophotographic photosensitive drum is defined as the longitudinal direction.

[0207] In addition, in the longitudinal direction, the side where the electrophotographic photosensitive drum receives a driving force from the image forming apparatus main body is referred to as a driving side, and the opposite side is referred to as a non-driving side.

[0208] The overall configuration and image forming process will be described with reference to FIGS. 2 and 3. FIG.

[0209] FIG. 2 is a cross-sectional view of an apparatus main body (electrophotographic image forming apparatus main body, image forming apparatus main body) A of an electrophotographic image forming apparatus according to one embodiment of the present invention and a process cartridge (hereinafter referred to as cartridge B).

[0210] FIG. 3 is a cross-sectional view of the cartridge B.

[0211] Here, the apparatus main body A refers to the electrophotographic image forming apparatus excluding the cartridge B. <Overall Configuration of Electrophotographic Image Forming Apparatus>

[0212] The electrophotographic image forming apparatus (image forming apparatus) shown in Figure 2 is a laser beam printer utilizing electrophotographic technology in which a cartridge B is detachably mountable in an apparatus main body A. When the cartridge B is mounted in the apparatus main body A, an exposure device 3 (laser scanner unit) is disposed for forming a latent image on an electrophotographic photosensitive drum 62 serving as an image carrier of the cartridge B. Also, a sheet tray 4 containing a recording medium (hereinafter referred to as sheet material PA) on which an image is to be formed is disposed below the cartridge B. The electrophotographic photosensitive drum 62 is a photosensitive member (electrophotographic photosensitive member) used for forming an electrophotographic image.

[0213] Furthermore, in the apparatus main body A, a pickup roller 5a, a pair of feeding rollers 5b, a pair of conveying rollers 5c, a transfer guide 6, a transfer roller 7, a conveying guide 8, a fixing device 9, a pair of discharge rollers 10, and a discharge tray 11 are arranged in this order along the conveying direction D of the sheet material PA. The fixing device 9 is composed of a heating roller 9a and a pressure roller 9b. <Image forming process>

[0214] Next, an outline of the image forming process will be described. Based on a print start signal, the electrophotographic photosensitive drum (hereinafter referred to as the photosensitive drum 62 or simply as the drum 62) is rotated in the direction of arrow R at a predetermined peripheral speed (process speed).

[0215] A charging roller (charging member) 66 to which a bias voltage is applied comes into contact with the outer peripheral surface of the drum 62 and charges the outer peripheral surface of the drum 62 uniformly.

[0216] The exposure device 3 outputs a laser beam L corresponding to the image information. The laser beam L passes through a laser opening 71h provided in the cleaning frame 71 of the cartridge B and scans and exposes the outer peripheral surface of the drum 62. As a result, an electrostatic latent image corresponding to the image information is formed on the outer peripheral surface of the drum 62.

[0217] On the other hand, as shown in FIG. 3, in the developing unit 20 as a developing device, the toner T in the toner chamber 29 is stirred and transported by the rotation of a transport member (stirring member) 43, and sent out to the toner supply chamber .

[0218] The toner T is carried on the surface of the developing roller 32 by the magnetic force of the magnet roller 34 (fixed magnet). The developing roller 32 is a developer carrier that carries developer (toner T) on its surface in order to develop the latent image formed on the drum 62.

[0219] The toner T is frictionally charged by the developing blade 42, and the thickness of the layer on the peripheral surface of the developing roller 32 as a developer carrier is regulated.

[0220] The toner T is supplied to the drum 62 in accordance with the electrostatic latent image, developing the latent image. This visualizes the latent image as a toner image. The drum 62 is an image carrier that carries the latent image and an image formed with toner (toner image, developer image) on its surface. As shown in FIG. 2 , a sheet material PA stored in the lower part of the apparatus main body A is fed from the sheet tray 4 by a pickup roller 5 a, a pair of feeding rollers 5 b, and a pair of conveying rollers 5 c in synchronization with the output of the laser light L. The sheet material PA is then conveyed via a transfer guide 6 to a transfer position between the drum 62 and a transfer roller 7. At this transfer position, the toner image is sequentially transferred from the drum 62 to the sheet material PA.

[0221] The sheet material PA onto which the toner image has been transferred is separated from the drum 62 and transported along a transport guide 8 to a fixing device 9. The sheet material PA then passes through a nip between a heating roller 9a and a pressure roller 9b that constitute the fixing device 9. A pressure and heat fixing process is performed at this nip, and the toner image is fixed to the sheet material PA. The sheet material PA, which has undergone the toner image fixing process, is transported to a pair of discharge rollers 10 and discharged onto a discharge tray 11.

[0222] 3, after transfer, the drum 62 has residual toner removed from its outer peripheral surface by a cleaning member 77, and is then reused in the image forming process. The toner removed from the drum 62 is stored in the waste toner chamber 71b of the cleaning unit 60. The cleaning unit 60 is a unit that includes the drum 62.

[0223] In the above, the charging roller 66, the developing roller 32, the transfer roller 7, and the cleaning member 77 are process means that act on the drum 62. <Overall Configuration of the Cartridge>

[0224] Next, the overall structure of cartridge B will be described with reference to Figures 3, 4, and 5. Figure 3 is a cross-sectional view of cartridge B, and Figures 4 and 5 are perspective views illustrating the structure of cartridge B. Note that in this embodiment, the screws used to join the various parts will not be described.

[0225] The cartridge B has a cleaning unit (photosensitive member holding unit, drum holding unit, image carrier holding unit) 60 and a developing unit (developer carrier holding unit) 20. One of the cleaning unit 60 and the developing unit 20 may be referred to as the first unit, and the other as the second unit.

[0226] Generally, a process cartridge is a cartridge in which an electrophotographic photosensitive member and at least one process means acting on the electrophotographic photosensitive member are integrated into one cartridge, and the cartridge is detachably mountable to the main body (main body) of an electrophotographic image forming apparatus. Examples of the process means include a charging means, a developing means, and a cleaning means. In this embodiment, the electrophotographic photosensitive member and the process means are supported by a cartridge frame.

[0227] As shown in FIG. 3 , the cleaning unit 60 includes a drum 62 as an electrophotographic photosensitive member, a charging roller 66 as a charging means, a cleaning member 77 as a cleaning means, and a cleaning frame 71 that supports these. On the drive side of the drum 62, a drive-side drum flange 63 provided on the drive side is rotatably supported by a hole 73a in a drum bearing 73. In a broad sense, the drum bearing 73 and cleaning frame 71 can be collectively referred to as the cleaning frame. The drum bearing 73 and cleaning frame 71 form the frame of the cleaning unit 60. The drum bearing 73 and cleaning frame 71 are also part of the frame of the cartridge. The drum 62 is rotatably supported by the frame.

[0228] On the non-drive side, as shown in FIG. 5, a drum shaft 78 is press-fitted into a hole 71c provided in the cleaning frame 71, and the hole (not shown) of the non-drive side drum flange is rotatably supported by the drum shaft 78.

[0229] Each drum flange is a bearing portion that is rotatably supported by a bearing portion.

[0230] In the cleaning unit 60 , the charging roller 66 and the cleaning member 77 are disposed in contact with the outer peripheral surface of the drum 62 .

[0231] The cleaning member 77 has a rubber blade 77a, which is a blade-shaped elastic member made of rubber as an elastic material, and a support member 77b that supports the rubber blade. The rubber blade 77a abuts against the drum 62 in a counter direction to the rotation direction of the drum 62. In other words, the rubber blade 77a abuts against the drum 62 with its tip facing upstream in the rotation direction of the drum 62.

[0232] As shown in FIG. 3, the waste toner removed from the surface of the drum 62 by the cleaning member 77 is stored in a waste toner chamber 71 b formed by the cleaning frame 71 and the cleaning member 77 .

[0233] As shown in FIG. 3, a catch sheet 65 for preventing waste toner from leaking from the cleaning frame 71 is provided on the edge of the cleaning frame 71 so as to come into contact with the drum 62 .

[0234] The charging roller 66 is rotatably attached to the cleaning unit 60 via charging roller bearings (not shown) at both ends of the cleaning frame 71 in the longitudinal direction.

[0235] The longitudinal direction of the cleaning frame 71 (the longitudinal direction of the cartridge B) is approximately parallel to the direction in which the rotation axis of the drum 62 extends (the axial direction). Therefore, hereinafter, when simply referring to the longitudinal direction or the axial direction without any particular specification, this refers to the axial direction of the drum 62.

[0236] The charging roller 66 is pressed against the drum 62 by a charging roller bearing 67 being pressed against the drum 62 by a biasing member 68. The charging roller 66 is rotated by the rotation of the drum 62.

[0237] As shown in Figure 3, the developing unit 20 has a developing roller 32, a developing container 23 that supports the developing roller 32, a developing blade 42, etc. The developing roller 32 is rotatably attached to the developing container 23 by bearing members 27 (Figure 5) and 37 (Figure 4) provided at both ends. The developing container 23, bearing members 27, and bearing members 37 form the frame of the developing unit 20. The developing container 23, bearing members 27, and bearing members 37 are also part of the frame of the cartridge, as are the drum bearing 73 and cleaning frame 71.

[0238] One of the frame of the cleaning unit 60 and the frame of the developing unit 20 may be referred to as the first frame, and the other as the second frame. The frame of the cleaning unit 60 and the frame of the developing unit 20 may also be collectively referred to simply as the frame. In this embodiment, the frame of the cartridge is separated into the frame of the cleaning unit 60 and the frame of the developing unit 20, but this configuration is not necessarily limited to this. The frame of the cartridge may be composed of two or more frames, or may not be separable into multiple frames.

[0239] A magnet roller 34 is provided within the developing roller 32. A developing blade 42 is disposed in the developing unit 20 to regulate the toner layer on the developing roller 32. As shown in FIGS. 4 and 5 , spacing members 38 are attached to both ends of the developing roller 32, and the developing roller 32 is held with a small gap between the drum 62 and the spacing members 38 when they abut against the drum 62. As shown in FIG. 3 , a blowout prevention sheet 33 is provided on the edge of the bottom member 22 so as to abut against the developing roller 32 to prevent toner from leaking from the developing unit 20. A transport member 43 is provided in the toner chamber 29 formed by the developer container 23 and the bottom member 22. The transport member 43 agitates the toner contained in the toner chamber 29 and transports the toner to the toner supply chamber 28.

[0240] As shown in FIGS. 4 and 5, the cartridge B is configured by combining a cleaning unit 60 and a developing unit 20 together.

[0241] When connecting the developing unit and the cleaning unit, first, the center of the first developer support boss 26a of the developer container 23 is aligned with the first hanging hole 71i on the drive side of the cleaning frame 71, and the center of the second developer support boss 23b is aligned with the second hanging hole 71j on the non-drive side. Specifically, by moving the developing unit 20 in the direction of arrow G, the first developer support boss 26a and the second developer support boss 23b fit into the first hanging hole 71i and the second hanging hole 71j. This allows the developing unit 20 to be movably connected to the cleaning unit 60. More specifically, the developing unit 20 is rotatably connected to the cleaning unit 60. Thereafter, the drum bearing 73 is assembled into the cleaning unit 60 to complete the cartridge B.

[0242] Further, a first end 46La of the driving side biasing member 46L is fixed to the surface 23c of the developing container 23, and a second end 46Lb abuts against a surface 71k that is a part of the cleaning unit.

[0243] The first end 46Ra of the non-driven side biasing member 46R is fixed to the surface 23k of the developing container 23, and the second end 46Rb abuts against the surface 71l that is part of the cleaning unit.

[0244] In this embodiment, the drive-side urging member 46L (FIG. 5) and the non-drive-side urging member 46R (FIG. 4) are formed of compression springs. The urging forces of these springs allow the drive-side urging member 46L and the non-drive-side urging member 46R to urge the developing unit 20 toward the cleaning unit 60, thereby reliably pressing the developing roller 32 toward the drum 62. The developing roller 32 is held at a predetermined distance from the drum 62 by spacing members 38 attached to both ends of the developing roller 32. <Cartridge Installation>

[0245] Next, the installation of the cartridge will be specifically described using Figures 1(a) and 1(b), Figures 6(a), 6(b), 6(c), 7(a), 8(a), 8(b), 9, Figures 10(a), 10(b), Figures 11(a), 11(b), 12(a), 12(b), Figures 13(a), 13(b), 14, 15, and 16.

[0246] 1(a) and (b) are perspective views of the cartridge to explain the shape of the drive transmission section and its surroundings. Fig. 6(a) is a perspective view of the cylindrical cam, Fig. 6(b) is a perspective view of the drive side plate as seen from the outside of the main assembly A of the apparatus, and Fig. 6(c) is a cross-sectional view (in the direction of the arrow in Fig. 6(b)) of the cylindrical cam attached to the drive side plate.

[0247] 7A is a cross-sectional view of a link portion of the image forming apparatus for explaining the link configuration, and FIG. 7B is a cross-sectional view of a drive portion of the image forming apparatus for explaining the movement of a drive transmission member.

[0248] Figure 8(a) is a cross-sectional view of the drive side guide portion of the image forming device to explain the installation of the cartridge, and Figure 8(b) is a cross-sectional view of the non-drive side guide portion of the image forming device to explain the installation of the cartridge.

[0249] FIG. 9 is an explanatory diagram of the drive train portion of the image forming apparatus for explaining the positional relationship of the drive train before the opening and closing door is closed.

[0250] FIG. 10A is an explanatory view for explaining the longitudinal positioning of the process cartridge B immediately before fitting into the positioning portion of the image forming apparatus.

[0251] FIG. 10B is an explanatory view of the state after fitting of the process cartridge B to the positioning portion of the image forming apparatus, for explaining the positioning of the process cartridge B in the longitudinal direction.

[0252] FIG. 11A is a cross-sectional view of the drive side of the image forming apparatus for explaining the positioning of the cartridge.

[0253] FIG. 11B is a cross-sectional view of the non-driving side of the image forming apparatus for explaining the positioning of the cartridge.

[0254] FIG. 12A is a cross-sectional view of a link portion of the image forming apparatus for explaining the link configuration, and FIG. 12B is a cross-sectional view of a drive portion of the image forming apparatus for explaining the movement of a drive transmission member.

[0255] FIG. 13A is a perspective view of the drive transmission member for explaining the shape of the drive transmission member.

[0256] FIG. 13B is an explanatory diagram of the drive transmission section of the apparatus main body A for explaining the drive transmission section.

[0257] FIG. 14 is a perspective view of the drive unit of the image forming apparatus for explaining the engagement space of the drive transmission unit.

[0258] FIG. 15 is a cross-sectional view of the drive transmission member for explaining the engagement space of the drive transmission member.

[0259] FIG. 16 is a cross-sectional view of the drum 62 and its surroundings in the apparatus main assembly A, for explaining the arrangement of the developing roller gear.

[0260] FIG. 17 is a cross-sectional view of the drive transmission member for explaining engagement of the drive transmission member.

[0261] First, we will explain the state in which the door of the apparatus main assembly A is open. As shown in Figure 7(a), the apparatus main assembly A is provided with the door 13, a rotating cam link 85, a cylindrical cam 86, cartridge pressing members 1 and 2, cartridge pressing springs 19 and 21, and a front plate 18. Also, as shown in Figure 7(b), the apparatus main assembly A is provided with a drive transmission member bearing 83, a drive transmission member 81, a drive transmission member spring 84, a drive side plate 15, and a non-drive side plate 16 (see Figure 10a).

[0262] The door 13 is rotatably attached to the drive side plate 15 and the non-drive side plate 16. As shown in Figures 6(a), 6(b), and 6(c), the cylindrical cam 86 is rotatably attached to the drive side plate 15 and movably in the longitudinal direction AM, and has two inclined surfaces 86a, 86b. The drive side plate 15 has two inclined surfaces 15d, 15e facing the two inclined surfaces 86a, 86b, and an end surface 15f facing the end surface 86c of the cylindrical cam 86.

[0263] As shown in FIG. 7A , the rotating cam link 85 has bosses 85a and 85b at both ends. These bosses 85a and 85b are rotatably attached to mounting holes 13a in the door 13 and mounting holes 86e in the cylindrical cam 86, respectively. When the door 13 is rotated open, the rotating cam link 85 moves in conjunction with the door 13. The movement of the rotating cam link 85 rotates the cylindrical cam 86, and the inclined surfaces 86a and 86b first contact the inclined surfaces 15d and 15e on the drive side plate 15, respectively. As the cylindrical cam 86 further rotates, the inclined surfaces 86a and 86b slide along the inclined surfaces 15d and 15e, causing the cylindrical cam 86 to move toward the drive side in the longitudinal direction. Finally, the cylindrical cam 86 moves until one end 86c of the cylindrical cam 86 abuts against the end face 15f of the drive side plate 15.

[0264] As shown in FIG. 7B , one end (fixed end 81c) of the drive transmission member 81 on the drive side in the axial direction is fitted into the drive transmission member bearing 83, and is supported rotatably and movably in the axial direction. A longitudinal center portion 81d of the drive transmission member 81 has a gap M between it and the drive side plate 15. The drive transmission member 81 has an abutment surface 81e, and the cylindrical cam 86 has another end 86d facing the abutment surface 81e. The drive transmission member spring 84 is a compression spring, and one end 84a abuts against a spring seat 83a provided on the drive transmission member bearing 83, and the other end 84b abuts against a spring seat 81f provided on the drive transmission member 81. This biases the drive transmission member 81 toward the non-drive side in the axial direction (the left side in FIG. 7B ). This bias causes the abutment surface 81e of the drive transmission member 81 to abut against the other end 86d of the cylindrical cam 86.

[0265] As described above, when the cylindrical cam 86 moves longitudinally toward the driving side (the right side in FIG. 7B), the drive transmission member 81 is pushed by the cylindrical cam 86 and moves toward the driving side. This causes the drive transmission member 81 to take a retracted position. In other words, by retracting the drive transmission member 81 from the movement path of the cartridge B, a space for installing the cartridge B is secured within the image forming apparatus main body A.

[0266] Next, the installation of the cartridge B will be described. As shown in Figures 8(a) and 8(b), the drive-side plate 15 has upper guide rails 15g and 15h as guides, and the non-drive-side plate 16 has upper guide rails 16d and 16e. The drum bearing 73 provided on the drive side of the cartridge B has a guided portion 73g and a rotation-stopped portion 73c. ​​In the installation direction of the cartridge B (see arrow C), the guided portion 73g and the rotation-stopped portion 73c are located upstream (the side indicated by arrow AO in Figure 15) of the axis of the coupling protrusion 63b (see Figure 1(a); details will be described later).

[0267] The mounting direction of the cartridge B is a direction substantially perpendicular to the axis of the drum 62. When referring to upstream or downstream in the mounting direction, upstream and downstream are defined in terms of the movement direction of the cartridge B immediately before the mounting of the cartridge B into the main assembly A of the apparatus is completed.

[0268] Furthermore, the cleaning frame 71 has a positioned portion 71d and a rotation-stopped portion 71g on the non-drive side in the longitudinal direction. When the cartridge B is mounted through the cartridge insertion opening 17 of the main body A of the apparatus, the guided portion 73g and rotation-stopped portion 73c of the cartridge B on the drive side are guided by the guide rail upper portion 15g and guide rail 15h of the main body A of the apparatus. The positioned portion 71d and rotation-stopped portion 71g of the cartridge B on the non-drive side are guided by the guide rail upper portion 16d and guide rail 16e of the main body A of the apparatus. In this way, the cartridge B is mounted in the main body A of the apparatus.

[0269] Here, a developing roller gear 30 is provided at the end of the developing roller 32 (see FIGS. 9 and 13B). In other words, the developing roller gear 30 is attached to the shaft of the developing roller 32.

[0270] The developing roller 32 and the developing roller gear 30 are coaxial and rotate about the axis Ax2 shown in FIG. 9. The developing roller 32 is disposed so that its axis Ax2 is substantially parallel to the axis Ax1 of the drum 62. Therefore, the axial direction of the developing roller 32 (the axial direction of the developing roller gear 30) is substantially the same as the axial direction of the drum 62.

[0271] The developing roller gear 30 is a drive input gear (cartridge side gear, drive input member) to which a drive force is input from the outside of the cartridge B (i.e., the apparatus main body A). The developing roller 32 is configured to rotate by the drive force received by the developing roller gear 30.

[0272] As shown in Figures 1(a) and (b), on the drive side of cartridge B, on the drum 62 side of the developing roller gear 30, there is provided a space 87 that is open so as to expose the developing roller gear 30 and the coupling protrusion 63b.

[0273] The coupling protrusion 63b is formed on the drive-side drum flange 63 attached to the end of the drum (see FIG. 9). The coupling protrusion 63b is a coupling portion (drum-side coupling portion, cartridge-side coupling portion, photosensitive-element-side coupling portion, input coupling portion, drive input portion) to which driving force is input from the outside of the cartridge B (i.e., the apparatus main body A) (see FIG. 9). The coupling protrusion 63b is disposed coaxially with the drum 62. In other words, the coupling protrusion 63b rotates around the axis Ax1.

[0274] The drive-side drum flange 63 having the coupling protrusion 63b is sometimes called a coupling member (drum-side coupling member, cartridge-side coupling member, photosensitive-element-side coupling member, drive input coupling member, input coupling member), or simply called a coupling.

[0275] In addition, in the longitudinal direction of the cartridge B, the side on which the coupling protrusion 63b is provided corresponds to the driving side, and the opposite side corresponds to the non-driving side.

[0276] 9, the developing roller gear 30 has a gear portion (input gear portion, cartridge side gear portion, developing side gear portion) 30a and an end face 30a1 provided on the drive side of the gear portion (see FIGS. 1(a), 1(b), and 9). The teeth (gear teeth) formed on the outer periphery of the gear portion 30a are helical teeth inclined with respect to the axis of the developing roller gear 30. In other words, the developing roller gear 30 is a helical gear (see FIG. 1(a)).

[0277] The drive transmission member (drive output member, main body side drive member) 81 has a gear portion (main body side gear portion, output gear portion) 81a for driving the developing roller gear 30. The gear portion 81a has an end face 81a1 at the end on the non-drive side (see FIGS. 13(a) and 13(b)).

[0278] The teeth (gear teeth) formed on the gear portion 81a are also helical teeth inclined with respect to the axis of the drive transmission member 81. In other words, the drive transmission member 81 also has a portion that serves as a helical gear.

[0279] The drive transmission member 81 also has a coupling recess 81b. The coupling recess 81b is a coupling portion (main body-side coupling portion, output coupling portion) provided on the device main body side. The coupling recess 81b is formed by forming a recess in a protrusion (cylindrical portion) provided on the tip of the drive transmission member 81 that can be coupled with the coupling protrusion 63b provided on the drum side.

[0280] The space 87 (see FIG. 1), which is configured so that the gear portion 30a and the coupling protrusion 63b are exposed, is for arranging the gear portion 81a of the drive transmission member 81 when the cartridge B is mounted in the apparatus main body A. Therefore, the space 87 is larger than the gear portion 81a of the drive transmission member 81 (see FIG. 15).

[0281] More specifically, in a cross section of cartridge B passing through gear portion 30a and perpendicular to the axis of drum 62 (axis of coupling protrusion 63b), an imaginary circle is drawn with the axis of drum 62 (axis of coupling protrusion 63b) as its center and the same radius as gear portion 81a. The interior of this imaginary circle is a space in which no components of cartridge B are disposed. The space defined by this imaginary circle is included within space 87 described above. In other words, space 87 is larger than the space indicated by the imaginary circle.

[0282] To put this another way, in the above cross section, an imaginary circle is drawn concentrically with the drum 62, with the radius being the distance from the axis of the drum 62 to the tooth tip of the gear portion 30a of the developing roller gear 30. Then, the inside of this imaginary circle is also a space in which no components of the cartridge B are disposed.

[0283] Due to the presence of the space 87, when the cartridge B is mounted in the apparatus main body A, the drive transmission member 81 does not interfere with the cartridge B. As shown in Figure 15, the space 87 allows the drive transmission member 81 to be disposed therein, thereby allowing the cartridge B to be mounted in the apparatus main body A.

[0284] Furthermore, when the cartridge B is viewed along the axis of the drum 62 (the axis of the coupling protrusion 63b), the gear teeth formed on the gear portion 30a are positioned close to the peripheral surface of the drum 62.

[0285] As shown in FIG. 15 , the gear portion 30 a is positioned so that the distance AV (the distance along a direction perpendicular to the axis) from the axis of the drum 62 to the tip of the gear tooth of the gear portion 30 a is in the range of 90% to 120% of the radius of the drum 62.

[0286] From the viewpoint of stably meshing the gear portion 30a with the gear portion 81a and stably transmitting the driving force from the gear portion 81a to the developing roller 32, it is more desirable that the distance AV be 90% or more and 110% or less of the radius of the drum 62. It is even more desirable that the distance AV be 93% or more and 107% or less of the radius of the drum 62.

[0287] In particular, in this embodiment, the radius of the drum 62 is 12 mm, and the distance from the axis of the drum 62 to the tip of the gear tooth (tooth tip) of the gear portion 30a is set within a range of 11.165 mm to 12.74 mm. In other words, the distance from the axis of the drum 62 to the tip of the gear tooth (tooth tip) of the gear portion 30a is within a range of 93% to 107% of the drum radius.

[0288] In the longitudinal direction, the end face 30a1 of the gear portion 30a of the developing roller gear 30 is disposed so as to be located closer to the driving side than the tip end 63b1 of the coupling protrusion 63b of the driving-side drum flange 63 (see FIGS. 9 and 20). The "driving side" here means the side farther from the non-driving side.

[0289] That is, in the longitudinal direction, the end face 30a1 is located farther than the tip end 63b1 from the non-drive side of the cartridge B. In other words, when measured along the longitudinal direction, the distance from the non-drive side of the cartridge B to the end face 30a1 is longer than the distance from the non-drive side of the cartridge B to the tip end 63b1.

[0290] In other words, the end face 30a1 is located outside the tip end 63b1 in the longitudinal direction. "Outside" here means the side farther from the center in a certain direction. In other words, the end face 30a1 of the gear portion 30a is located farther from the center of the cartridge B in the longitudinal direction than the tip end 63b1. When measured along the longitudinal direction, the distance from the center of the cartridge B to the end face 30a1 of the gear portion 30a is longer than the distance from the center of the cartridge B to the tip end 63b1.

[0291] In other words, the tip portion 63b1 is located "inside" the end face 30a1 in the longitudinal direction. "Inside" here means the side closer to the center in a certain direction. In other words, the tip portion 63b1 is located closer to the center of the cartridge B in the longitudinal direction than the end face 30a1 of the gear portion 30a. When measured along the longitudinal direction, the distance from the center of the cartridge B to the tip portion 63b1 is shorter than the distance from the center of the cartridge B to the end face 30a1 of the gear portion 30a.

[0292] As a result, in the axial direction of the developing roller gear 30, the gear teeth of the gear portion 30a have an exposed portion that is exposed from the cartridge B (see FIG. 1). In particular, in this embodiment, as shown in FIG. 15, the gear portion 30a is exposed over a range of 64 degrees or more. In other words, when viewing the cartridge B from the drive side, if the line connecting the center of the drum 62 and the center of the developing roller gear 30 is taken as the reference line, then both sides of the developing roller gear 30 relative to this reference line are exposed over a range of at least 32 degrees or more.

[0293] In Figure 15, the angle AW has the center (axis) of the developing roller gear 30 as the origin and indicates the angle from the reference line to the position where the gear portion 30a begins to be covered by the driving side developing side member 26, and is "AW≧32°".

[0294] The overall exposure angle of the gear portion 30a can be expressed as 2AW, which satisfies the relationship "2AW≧64°" as described above.

[0295] If the gear portion 30a of the developing roller gear 30 is exposed from the driving side developing member 26 so as to satisfy the above relationship, the gear portion 81a meshes with the gear portion 30a without interfering with the driving side developing member 26, thereby enabling drive transmission.

[0296] At least a part of the exposed portion of this gear portion 30a is positioned further outside (on the driving side) of the cartridge B than the tip portion 63b1 of the coupling protrusion 63b, and faces the axis of the drum (see Figures 1, 9, and 20).

[0297] 9 and 21 show a state in which the gear teeth arranged on the exposed portion 30a3 of the gear portion 30a face the rotation axis Ax1 of the drum 62 (the rotation axis of the coupling protrusion 63b).

[0298] In FIG. 20, the axis Ax1 of the drum 62 is located above the exposed portion 30a3 of the gear portion 30a.

[0299] In FIG. 9, at least a portion of the gear portion 30a protrudes further toward the driving side than the coupling protrusion 63b in the axial direction, so that the gear portion 30a overlaps with the gear portion 81a of the drive transmission member 81 in the axial direction.

[0300] Since a part of the gear portion 30a is exposed to face the axis Ax1 of the drum 62, the gear portion 30a and the gear portion 81a of the drive transmission member 81 may come into contact with each other during the process of inserting the cartridge B into the main assembly A of the apparatus.

[0301] 20 shows a state in which the outer end surface 30a1 of the gear portion 30a is disposed on the arrow D1 side of the tip end 63b1 of the coupling protrusion 63b. The arrow D1 points outward in the axial direction.

[0302] Due to the above-mentioned positional relationship, the gear portion 30a of the developing roller gear 30 and the gear portion 81a of the drive transmission member 81 can mesh with each other during the process of mounting the cartridge B into the main assembly A of the apparatus.

[0303] In addition, in the mounting direction C of the cartridge B, the center (axis) of the gear portion 30a is arranged on the upstream side (the side of the arrow AO in FIG. 15) of the center (axis) of the drum 62.

[0304] The arrangement of the developing roller gear 30 will be described in more detail. As shown in Figure 16, which is a cross-sectional view from the non-drive side, a line connecting the center of the drum 62 to the center of the charging roller 66 is set as a reference line (start line) indicating the angle reference (0°). At this time, the center (axis) of the developing roller gear 30 is located in an angle range of 64° to 190° downstream in the rotation direction of the drum 62 (clockwise in Figure 16) with respect to the reference line.

[0305] More precisely, the center of the drum 62 is set as the origin, the half line extending from the center of the drum 62 to the center of the charging roller 66 is set as the starting line, and the rotation direction of the drum is set as the positive direction of the angle. Then, the deviation angle of the polar coordinate indicating the center of the developing roller satisfies the following relationship: 64°≦Declination angle of the polar coordinate indicating the center of the developing roller≦190°

[0306] There is a certain degree of freedom in the arrangement of the charging roller 66 and the developing roller gear 30. The angle at which the charging roller 66 and the developing roller gear 30 are closest to each other is indicated by arrow BM, which is 64° in this embodiment as described above. On the other hand, the angle at which they are farthest apart is indicated by arrow BN, which is 190° in this embodiment.

[0307] As described above, the unit provided with the developing roller gear 30 (developing unit 20) is movable relative to the drum 62 and the unit provided with the coupling protrusion 63b (cleaning unit 60). In other words, the developing unit 20 is rotatable relative to the cleaning unit 60, with the first developing support boss 26a and the second developing support boss 23b (see FIGS. 4 and 5) as the rotation center (rotation axis). Therefore, the center-to-center distance (axis-to-axis distance) of the developing roller gear 30 and the drum 62 is variable, and the developing roller gear 30 can move within a certain range relative to the axis of the drum 62 (axis of the coupling protrusion 63b).

[0308] 9, when the gear portion 30a and the gear portion 81a come into contact with each other during the insertion of the cartridge B, the gear portion 30a is pushed by the gear portion 81a and moves away from the axis of the drum 62 (the axis of the coupling protrusion 63b).This reduces the impact of the contact between the gear portion 30a and the gear portion 81a.

[0309] As shown in FIGS. 10A and 10B, the drum bearing 73 has a fitted portion 73h as a portion to be positioned in the longitudinal direction (axial direction) (portion to be positioned in the axial direction).

[0310] The drive side plate 15 of the apparatus main assembly A has a fitting portion 15j that can fit into the fitting portion 73h. The fitting portion 73h of the cartridge B fits into the fitting portion 15j of the apparatus main assembly A during the above-mentioned installation process, thereby determining the longitudinal (axial) position of the cartridge B (see FIG. 10B). In this embodiment, the fitting portion 73h is a slit (groove) (see FIG. 1B). This slit communicates with the space 87. That is, the slit (fitting portion 73h) forms an open space relative to the space 87.

[0311] The arrangement of the mated portion 73h will be described in detail using Figure 20. Note that Figure 20 is an explanatory diagram (schematic diagram) for illustrating the arrangement of the mated portion 73h relative to the gear portion 30a or the coupling protrusion 63b. As shown in Figure 20, this slit (matted portion 73h) is a space formed between two portions (an outer portion 73h1 and an inner portion 73h2 of the mated portion 73h) arranged along the axial direction. In the axial direction, the inner end portion (inner portion 73h2) of the mated portion 73h is arranged more inward (toward arrow D2) than the end face 30a1 of the gear portion 30a. In the axial direction, the outer end portion (outer portion 73h1) of the mated portion 73h is arranged more outward (toward arrow D1) than the tip portion 63b1 of the coupling protrusion 63b.

[0312] Next, we will explain the state of closing the door 13. As shown in Figures 8(a), 8(b), 11(a), and 11(b), the drive side plate 15 has an upper positioning portion 15a, a lower positioning portion 15b, and a rotation stopper portion 15c for positioning, and the non-drive side plate 16 has a positioning portion 16a and a rotation stopper portion 16c.

[0313] The drum bearing 73 has an upper positioned portion (first positioned portion, first protrusion, first protrusion) 73d and a lower positioned portion (second positioned portion, second protrusion, second protrusion) 73f.

[0314] Furthermore, the cartridge pressing members 1 and 2 are rotatably attached to both axial ends of the door 13. The cartridge pressing springs 19 and 21 are attached to both longitudinal ends of a front plate provided in the image forming apparatus A. The drum bearing 73 has a pressed portion 73e as a biasing force receiving portion, and the cleaning frame 71 has a pressed portion 71o on the non-drive side (see FIG. 3). By closing the door 13, the pressed portions 73e and 71o of the cartridge B are pressed by the cartridge pressing members 1 and 2 biased by the cartridge pressing springs 19 and 21 of the apparatus main body A.

[0315] As a result, on the drive side, the upper positioned portion 73d, the lower positioned portion 73f, and the rotation-stopped portion 73c of cartridge B abut against the upper positioning portion 15a, the lower positioning portion 15b, and the rotation-stopped portion 15c of the apparatus main body A, respectively. As a result, cartridge B and drum 62 are positioned on the drive side. Also, on the non-drive side, the positioned portion 71d and the rotation-stopped portion 71g of cartridge B abut against the positioning portion 16a and the rotation-stopped portion 16c of the apparatus main body A, respectively. As a result, cartridge B and drum 62 are positioned on the non-drive side.

[0316] 1(a) and 1(b), the upper positioned portion 73d and the lower positioned portion 73f are disposed near the drum 62. The upper positioned portion 73d and the lower positioned portion 73f are aligned along the rotation direction of the drum 62.

[0317] Furthermore, in the drum bearing 73, a space (arc-shaped recess) 73l for disposing the transfer roller 7 (see FIG. 11) needs to be secured between the upper positioned portion 73d and the lower positioned portion 73f. Therefore, the upper positioned portion 73d and the lower positioned portion 73f are disposed apart from each other.

[0318] Additionally, the upper positioned portion 73d and the lower positioned portion 73f are protrusions that protrude inward in the axial direction from the drum bearing 73. As described above, it is necessary to ensure a space 87 around the coupling protrusion 63b. Therefore, the upper positioned portion 73d and the lower positioned portion 73f do not protrude outward in the axial direction, but instead protrude inward to ensure the space 87.

[0319] The upper positioned portion 73d and the lower positioned portion 73f are protrusions that are arranged to partially cover the drum 62. In other words, the upper positioned portion 73d, 73f are protruding portions that protrude (overhang) inward in the axial direction of the drum 62. When the upper positioned portion 73d and the drum 62 are projected onto the axis of the drum 62, the projected areas of the upper positioned portion 73d and the drum 62 at least partially overlap. In this regard, the lower positioned portion 73f is similar to the upper positioned portion 73d.

[0320] Additionally, the upper positioned portion 73d and the lower positioned portion 73f are arranged so as to partially cover the drive-side drum flange 63 provided at the end of the drum 62. When the upper positioned portion 73d and the drive-side drum flange 63 are projected onto the axis of the drum 62, the projected areas of the upper positioned portion 73d and the drive-side drum flange 63 at least partially overlap. In this regard, the lower positioned portion 73f is similar to the upper positioned portion 73d.

[0321] The pressed portions 73e and 71o are protruding portions of the frame of the cleaning unit arranged at one end (drive side) and the other end (non-drive side) of the cartridge B in the longitudinal direction. In particular, the pressed portion 73e is provided on the drum bearing 73. The pressed portions 73e and 71o protrude in a direction intersecting the axial direction of the drum 62 and away from the drum 62.

[0322] 12(a) and 12(b), the drive-side drum flange 63 has a coupling protrusion 63b on the drive side and a tip portion 63b1 at the tip of the coupling protrusion 63b. The drive transmission member 81 has a coupling recess 81b and a tip portion 81b1 of the coupling recess 81b on the non-drive side. When the opening / closing door 13 is closed, the cylindrical cam 86 moves longitudinally to the non-drive side (the side closer to cartridge B) via the rotating cam link 85 while the inclined surfaces 86a and 86b rotate along the inclined surfaces 15d and 15e of the drive-side plate 15. As a result, the drive transmission member 81, which was in the retracted position, moves longitudinally to the non-drive side (the side closer to cartridge B) by the drive transmission member spring 84. Because the gear teeth of gear portion 81a and gear portion 30a are inclined with respect to the direction of movement of drive transmission member 81, the gear teeth of gear portion 81a come into contact with the gear teeth of gear portion 30a as the drive transmission member 81 moves. At this point, movement of drive transmission member 81 toward the non-drive side stops.

[0323] Even after the drive transmission member 81 stops, the cylindrical cam 86 continues to move to the non-drive side, and the drive transmission member 81 and the cylindrical cam 86 move away from each other.

[0324] Next, as shown in FIGS. 1, 13(a), and 17, the drum bearing 73 has a concave bottom surface 73i. The drive transmission member 81 has a bottom portion 81b2 at the bottom of the coupling recess 81b for positioning. The coupling recess 81b of the drive transmission member 81 is a hole with a substantially triangular cross section. When viewed from the non-drive side (the cartridge side, the opening side of the recess 81b), the coupling recess 81b has a shape that twists in a counterclockwise direction N toward the drive side (the innermost side of the recess 81b). The gear portion 81a of the drive transmission member 81 is a helical gear, and when viewed from the non-drive side (the cartridge side), the gear teeth twist in a counterclockwise direction N toward the drive side. In other words, the coupling recess 81b and the gear portion 81a are inclined (twisted) in the opposite direction to the rotational direction CW of the drive transmission member 81 as they approach the rear end (fixed end 81c) of the drive transmission member 81.

[0325] The gear portion 81a and the coupling recess 81b are arranged so that the axis of the gear portion 81a and the axis of the coupling recess 81b overlap the axis of the drive transmission member 81. In other words, the gear portion 81a and the coupling recess 81b are arranged coaxially (concentrically).

[0326] The coupling protrusion 63b of the drive-side drum flange 63 has a substantially triangular cross section and a convex shape (protrusion, projection). The coupling protrusion 63b is twisted counterclockwise O from the drive side (the tip end of the coupling protrusion 63b) to the non-drive side (the bottom end of the coupling protrusion 63b) (see Figure 22). In other words, the coupling protrusion 63b is inclined (twisted) counterclockwise (in the direction of drum rotation) from the outside to the inside of the cartridge in the axial direction.

[0327] The coupling protrusion 63b has a triangular prism whose corners (ridges) form the vertices of the triangle, which act as driving force receiving portions that actually receive the driving force from the coupling recess 81b. This driving force receiving portion is inclined toward the drum rotation direction as it moves from the outside to the inside of the cartridge in the axial direction. The inner surface (inner peripheral surface) of the coupling recess 81b acts as a driving force applying portion that applies driving force to the coupling protrusion 63b.

[0328] The gear portion 30a of the developing roller gear 30 is a helical gear, and has a shape that is twisted (inclined) in the clockwise direction P from the drive side to the non-drive side (see FIG. 22). In other words, the gear teeth (helical teeth) of the gear portion 30a are inclined (twisted) in the clockwise direction P (the rotation direction of the developing roller and developing roller gear) from the outside to the inside of the cartridge in the axial direction of the gear portion 30a. In other words, the gear 30a is inclined (twisted) in the opposite direction to the rotation direction of the drum 62 from the outside to the inside in the axial direction.

[0329] As shown in FIG. 13 , the drive transmission member 81 is rotated by a motor (not shown) in the clockwise direction CW (opposite the direction of arrow N in FIG. 13 ) as viewed from the non-drive side (cartridge side). As a result, a thrust force (a force generated in the axial direction) is generated by the helical meshing of the gear portion 81a of the drive transmission member 81 and the gear portion 30a of the developing roller gear 30. An axial (longitudinal) force FA is applied to the drive transmission member 81, and the drive transmission member 81 attempts to move longitudinally toward the non-drive side (the side approaching the cartridge). In other words, the drive transmission member 81 approaches and comes into contact with the coupling protrusion 63b.

[0330] In particular, in this embodiment, the gear portion 81a of the drive transmission member 81 has helical teeth that are twisted so that each tooth moves 5 to 8.7 mm in the axial direction (see FIG. 13). This corresponds to a twist angle of the gear portion 81a of 15° to 30°. The twist angle of the developing roller gear 30 (gear portion 30a) is also 15° to 30°. In this embodiment, a twist angle of 20° was adopted for the gear portion 81a and the gear portion 30a.

[0331] When the drive transmission member 81 rotates and the phases of the triangular shapes of the coupling recesses 81b and the coupling protrusions 63b match, the coupling protrusions 63b and the coupling recesses 81b engage (couple).

[0332] When the convex portion 63b and the coupling concave portion 81b engage with each other, a new thrust force FC is generated because both the coupling concave portion 81b and the coupling convex portion 63b are twisted (inclined) with respect to the axis.

[0333] In other words, a force FC acting toward the non-drive side (the side approaching the cartridge) in the longitudinal direction acts on the drive transmission member 81. This force FC combined with the aforementioned force FA causes the drive transmission member 81 to move further toward the non-drive side (the side approaching the cartridge) in the longitudinal direction. In other words, the coupling protrusion 63b acts to move the drive transmission member 81 closer to the coupling protrusion 63b of the cartridge B.

[0334] The drive transmission member 81 drawn by the coupling protrusion 63b has a tip end 81b1 thereof abutting against the concave bottom surface 73i of the drum bearing 73, and is positioned in the longitudinal direction (axial direction).

[0335] Furthermore, a reaction force FB of the force FC acts on the drum 62, and this reaction force (resistance) FB moves the drum 62 toward the driving side (the side closer to the drive transmission member 81, the outside of the cartridge B) in the longitudinal direction. In other words, the drum 62 and the coupling protrusion 63b are drawn toward the drive transmission member 81. As a result, the tip end 63b1 of the coupling protrusion 63b of the drum 62 abuts against the bottom 81b2 of the coupling recess 81b. This also positions the drum 62 in the axial direction (longitudinal direction).

[0336] That is, the coupling protrusion 63b and the coupling recess 81b are attracted to each other, so that the positions of the drum 62 and the drive transmission member 81 in the axial direction are determined.

[0337] In this state, the drive transmission member 81 is in the drive position, i.e., the drive transmission member 81 is in a position for transmitting drive force to the coupling protrusion 63b and the gear portion 30a.

[0338] Furthermore, the centering action of the triangular shape of the coupling recess 81b determines the center of the tip of the drive transmission member 81 relative to the drive-side drum flange 63. In other words, the drive transmission member 81 is centered relative to the drive-side drum flange 63, and the drive transmission member 81 and the photosensitive member are coaxial. This allows the drive to be transmitted from the drive transmission member 81 to the developing roller gear 30 and the drive-side drum flange 63 with high precision.

[0339] The coupling recess 81b and the coupling protrusion 63b that engages with it can also be considered as a centering portion. That is, when the coupling recess 81b engages with the coupling protrusion 63b, the drive transmission member 81 and the drum become coaxial with each other. In particular, the coupling recess 81b will be called the main body side centering portion (image forming apparatus main body side centering portion), and the coupling protrusion 63b will be called the cartridge side centering portion.

[0340] As described above, the engagement of the coupling is assisted by the forces FA and FC acting on the drive transmission member 81 toward the non-drive side.

[0341] Furthermore, by positioning the drive transmission member 81 by means of a drum bearing (bearing member) 73 provided on the cartridge B, the positioning accuracy of the drive transmission member 81 relative to the cartridge B can be improved.

[0342] Since the positional accuracy in the longitudinal direction between the gear portion 30a of the developing roller gear 30 and the gear portion 81a of the drive transmission member 81 is improved, it is possible to reduce the width of the gear portion 30a of the developing roller gear 30. This makes it possible to reduce the size of the cartridge B and the apparatus main body A into which the cartridge B is mounted.

[0343] To summarize this embodiment, the gear portion 81a of the drive transmission member 81 and the gear portion 30a of the developing roller gear 30 have helical teeth. Helical teeth provide a higher contact ratio between the gears than spur teeth. As a result, the rotational accuracy of the developing roller gear 30 is improved, and the developing roller gear 30 rotates smoothly.

[0344] Furthermore, the inclination direction of the helical teeth of the gear portion 30a and the gear portion 81a is specified so that forces (forces FA and FB) that attract each other are generated between the gear portion 30a and the gear portion 81a. In other words, when the gear portion 30a and the gear portion 81a rotate in mesh with each other, a force is generated that moves the coupling recess 81b provided in the drive transmission member 81 and the coupling protrusion 63b provided at the end of the drum 62 closer together. As a result, the drive transmission member 81 moves toward the cartridge B, and the coupling recess 81b also moves closer to the coupling protrusion 63b. This assists the connection (coupling) between the coupling recess 81b and the coupling protrusion 63b.

[0345] Furthermore, the direction in which the coupling protrusion 63b (driving force receiving portion) is inclined relative to the drum axis and the direction in which the helical teeth of the gear portion 30a of the developing roller gear 30 are inclined relative to the axis of the gear portion 30a are opposite to each other (see FIG. 38). As a result, the movement of the drive transmission member 81 is assisted not only by the force generated by the engagement (meshing) of the gear portion 30a and the gear portion 81a, but also by the force (force FC) generated by the engagement (coupling) of the coupling protrusion 63b and the coupling recess 81b. In other words, as the coupling protrusion 63b and the coupling recess 81b rotate in a coupled state, the coupling protrusion 63b and the coupling recess 81b attract each other. As a result, the coupling protrusion 63b and the coupling recess 81b are stably engaged (coupled).

[0346] The drive transmission member 81 is biased toward the coupling protrusion 63b by an elastic member (drive transmission member spring 84) (see FIG. 7A). In this embodiment, the force of the drive transmission member spring 84 can be weakened by the amount of force FA and force FC (see FIG. 13B). This reduces the frictional force between the drive transmission member spring 84 and the drive transmission member 81 that occurs when the drive transmission member 81 rotates, thereby reducing the torque required to rotate the drive transmission member 81. This also reduces the load on the motor that rotates the drive transmission member 81. Furthermore, the sliding noise between the drive transmission member 81 and the drive transmission member spring 84 can also be reduced.

[0347] In this embodiment, the drive transmission member 81 is biased by an elastic member (drive transmission member spring 84), but the elastic member is not necessarily required. That is, if the gear portion 81a and the gear portion 30a are arranged so as to at least partially overlap each other in the axial direction and the gear portion 81a and the gear portion 30a mesh with each other when the cartridge is mounted in the main assembly of the apparatus, the elastic member can be eliminated. In other words, when the gear portion 81a rotates, the meshing of the gear portion 81a and the gear portion 30a generates a force that attracts the coupling protrusion 63b and the coupling recess 81b together. In other words, even without the elastic member (drive transmission member spring 84), the force generated by the meshing of the gears moves the drive transmission member 81 toward the cartridge B. This allows the coupling protrusion 63b to engage with the coupling recess 81b.

[0348] In this way, without the elastic member, there is no friction between the elastic member and the drive transmission member 81, which further reduces the rotational torque of the drive transmission member 81. It is also possible to eliminate noise caused by sliding between the drive transmission member 81 and the elastic member. It is also possible to reduce the number of parts in the image forming apparatus, which simplifies the configuration of the image forming apparatus and reduces costs.

[0349] Furthermore, the coupling protrusion 63b of the drive-side drum flange 63 is coupled to the recess 81b of the drive transmission member 81 while the drive transmission member 81 is rotating. Here, the coupling protrusion 63b is inclined (twisted) toward the rotation direction of the photosensitive drum as it moves from the outside to the inside of the cartridge in the axial direction of the drum 62. In other words, because the coupling protrusion 63b is inclined (twisted) along the rotation direction of the drive transmission member 81, the coupling protrusion 63b is easily coupled to the rotating recess 81b.

[0350] In this embodiment, as shown in FIGS. 1(a) and 1(b), when the cartridge B is viewed from the drive side, the coupling protrusion 63b (drum 62) rotates counterclockwise O, and the developing roller gear 30 (developing roller 32) rotates clockwise P.

[0351] However, when viewed from the non-drive side, cartridge B can also be configured so that the coupling protrusion 63b (drum 62) rotates counterclockwise and the developing roller gear 30 (developing roller 32) rotates clockwise. In other words, by changing the layout of the main assembly A of the apparatus or cartridge B, the rotation directions of the coupling protrusion 63b (drum 62) and the developing roller gear 30 can be opposite to those in this embodiment. In any case, when the coupling protrusion 63b and the developing roller gear 30 are viewed from the same direction, the rotation directions of the coupling protrusion 63b and the developing roller gear 30 are opposite to each other. One of them rotates clockwise and the other rotates counterclockwise.

[0352] That is, if the cartridge B is viewed so that the rotation direction of the coupling projection 63b is counterclockwise (in this embodiment, if the cartridge B is viewed from the drive side), the rotation direction of the developing roller gear 30 is clockwise.

[0353] In this embodiment, the developing roller gear 30 is used as the drive input gear that meshes with the drive transmission member 81, but another gear may be used as the drive input gear.

[0354] In other words, the drive input gear (developing roller gear 30) may be configured not to be connected to the developing roller 32. In this case, the drive input gear may be configured to transmit the drive force received from the drive transmission member 81 to a member other than the developing roller 32, or may be configured not to transmit the received drive force to anywhere. Also, in this embodiment, the cartridge has the developing roller 32, but the cartridge does not necessarily have to have the developing roller 32.

[0355] Even in these cases, if the drive input gear of the cartridge meshes with the gear 81a and receives the drive force, a force is generated that pulls the drive transmission member 81 toward the coupling protrusion 63b.

[0356] Even in a configuration in which the drive input gear does not transmit the drive force to the developing roller 32, etc., it is possible to rotate the developing roller 32 as long as the cartridge has a separate drive transmission path that transmits the drive force from the coupling protrusion 63b to the developing roller 32, etc. For example, if a gear is provided on the photosensitive drum 62 and a gear that meshes with the gear of the photosensitive drum 62 is provided on the developing roller 32, the drive force received by the coupling protrusion 63b can be transmitted to the developing roller via the photosensitive drum and these gears.

[0357] However, if the developing roller gear 30 is configured to transmit the driving force to the developing roller 32 as in this embodiment, the path for transmitting the driving force from the drive transmission member 81 to the developing roller 32 is shortened, which has the advantage of making it easier to simplify the cartridge structure.

[0358] Next, the conditions for coupling engagement will be specifically described using Figures 1, 13(a), 17, 18(a), 18(b), 19(a), and 19(b). Figure 18(a) is a cross-sectional view of the image forming apparatus drive unit as seen from the opposite direction to the cartridge B installation direction to explain the distance of the drive transmission unit. Figure 18(b) is a cross-sectional view of the image forming apparatus drive unit as seen from the drive side to explain the distance of the drive transmission unit. Figure 19(a) is a cross-sectional view of the image forming apparatus drive unit as seen from the drive side to explain the gap in the coupling unit. Figure 19(b) is a cross-sectional view of the image forming apparatus drive unit as seen from the drive side to explain the gap in the coupling unit.

[0359] As shown in Figures 1, 18(a), and 18(b), the drum bearing 73 has a regulating portion 73j that serves as a tilt regulating portion (movement regulating portion, position regulating portion, stopper) that regulates the movement of the drive transmission member 81 and regulates (suppresses) the tilting of the drive transmission member 81.

[0360] The drive transmission member 81 has a cylindrical portion 81i (see FIG. 18A) on the non-drive side (the side closer to the cartridge B). The cylindrical portion 81i is a cylindrical portion (protrusion) in which a coupling recess 81b is formed.

[0361] As described above, when the drive transmission member 81 starts to rotate, the gear portion 81a of the drive transmission member 81 and the gear portion 30a of the developing roller gear 30 mesh together, as shown in Figure 9. Meanwhile, the coupling recess 81b and the coupling protrusion 63b are not coupled or are insufficiently coupled. In this state, when the gear portion 81a transmits driving force to the gear portion 30a, meshing of the gears generates a meshing force FD (Figure 18(b)) in the gear portion 81a.

[0362] When this meshing force FD is applied to the drive transmission member 81, the drive transmission member 81 tilts. In other words, since the drive transmission member 81 is supported only by the fixed end 81c (see FIG. 18A: the end farther from the cartridge B), which is the end on the driving side, as described above, the drive transmission member 81 tilts with the end 81c (fixed end) on the driving side as the fulcrum. This causes the end (free end, tip) of the drive transmission member 81 on the side where the coupling recess 81b is provided to move.

[0363] If the drive transmission member 81 tilts significantly, the coupling recess 81b will not be able to couple with the coupling protrusion 63b. To avoid this, the cartridge B is provided with a regulating portion 73j, which limits (regulates) the tilt of the drive transmission member 81 within a certain range. In other words, when the drive transmission member 81 tilts, the regulating portion 73j supports the drive transmission member 81, thereby preventing the tilt from becoming too large.

[0364] The restricting portion 73j of the drum bearing 73 is an arc-shaped curved surface portion disposed so as to face the axis of the drum 62 (the axis of the coupling protrusion 63b). The restricting portion 73j can also be considered as a protruding portion that protrudes to cover the drum axis. A space is formed between the restricting portion 73j and the drum axis in which no components of the process cartridge B are disposed, and the drive transmission member 81 is configured to be disposed in this space. The restricting portion 73j faces the space 87 shown in FIG. 1, and the restricting portion 73j forms the edge (outer edge) of the space 87.

[0365] The restricting portion 73j is disposed at a position where it can prevent the drive transmission member 81 from moving (tilting) due to the meshing force FD.

[0366] The direction in which the meshing force FD is generated is determined by the front pressure angle α of the gear portion 81a (i.e., the front pressure angle α of the developing roller gear 30). The direction in which the meshing force FD is generated is inclined by (90+α') degrees toward the upstream AK in the rotation direction of the drum 62 with respect to the arrow (semi-straight line) LN extending from the center 62a of the drum 62 (i.e., the center of the drive transmission member 81) toward the center 30b of the developing roller gear 30.

[0367] In addition, the standard front pressure angle α for a helical gear with a 20° helix angle is 21.2°. In this embodiment, the front pressure angle α of the gear portion 81a and the gear portion 30a is also 21.2°. In this case, the inclination of the meshing force FD with respect to the arrow LN is 111.2°. However, a different value can be used as the front pressure angle of the gear portion 81a and the gear portion 30a, and in that case, the direction of the meshing force FD will also change. The front pressure angle α also changes depending on the helical angle of the helical gear, and the front pressure angle α is preferably 20.6° or more and 22.8° or less.

[0368] 18(b), if a half line FDa is extended starting from the center 62a of the photosensitive drum 62a and extending in the same direction as the meshing force FD, the restricting portion 73j is positioned so as to straddle this half line FDa. Note that the half line FDa is a line obtained by tilting (rotating) the half line LN by (90 + α') degrees upstream in the rotation direction of the drum 62, with the center of the drum 62 as the origin (axis, fulcrum). In this embodiment, the half line FDa is tilted by 111.2 degrees with respect to the half line LN.

[0369] The restricting portion 73j does not necessarily have to be disposed on the line FDa, but may be disposed near the half line FDa. Specifically, it is desirable that at least a portion of the restricting portion 73j be disposed somewhere within a range of plus or minus 15° with respect to the half line FDa.

[0370] The half line FDa is a line obtained by rotating the half line LN by (90 + α) degrees upstream in the rotation direction of the drum 62. Therefore, the restricting portion 73j is preferably located in a range of (75 + α) degrees to (105 + α) degrees upstream in the drum rotation direction with respect to the half line LN, with the center of the drum 62 as the origin. Considering that the preferred value of the front pressure angle α is 20.6 degrees or more and 22.8 degrees or less, the preferred range for arranging the restricting portion 73j is 95.6 degrees or more and 127.8 degrees or less with respect to the half line LN. In this embodiment, since the front pressure angle α is 21.2 degrees, the preferred range for arranging the restricting portion 73j is 96.2 degrees or more and 126.2 degrees or less.

[0371] As another example of a suitable arrangement of the restricting portions 73j, a plurality of restricting portions 73j may be arranged on either side of the half-line FDa, with the half-line FDa sandwiched between them (see FIG. 26). In this case, the restricting portions 73j can also be considered to be arranged across the line FDa.

[0372] Furthermore, it is desirable that the restricting portion 73j be disposed on the upstream side AO (see FIG. 15) in the cartridge mounting direction C (see FIG. 11A) with respect to the center (axis) of the coupling protrusion 63b, in order to prevent the restricting portion 73j from interfering with the mounting of the cartridge B.

[0373] The range (area) in which the restricting portion 73j is disposed on the drum bearing 73 can also be described as follows.

[0374] In a plane perpendicular to the axis of the drum 62 (see FIG. 18(b)), a straight line LA is drawn that passes through the center 62a of the drum 62 and the center 30b of the developing roller gear 30. In this case, the regulating portion 73j is disposed on the side of the straight line LA where the charging roller is disposed (i.e., the side indicated by the arrow AL).

[0375] Alternatively, the restricting portion 73j is disposed in an area AL on the opposite side of the line LA passing through the center 62a of the drum 62 and the gear center 30b from the side where the drum 62 is exposed (the side where the drum 62 faces the transfer roller 7). Note that before the cartridge B is mounted in the apparatus main body A, a cover, shutter, etc. covering the drum 62 may be provided on the cartridge B, and the drum 62 may not be exposed. However, the side where the drum 62 is exposed here means the side where the drum 62 is exposed when the cover, shutter, etc. are removed.

[0376] Furthermore, in a plane perpendicular to the axis of the drum 62, the range (area AL) in which the restricting portion 73j is disposed can also be described as follows using the circumferential direction (rotational direction) of the drum 62.

[0377] A half line (primary line) LN is drawn starting from the center 62a of the drum 62 and extending toward the center 30b of the gear portion 30a of the developing roller gear 30. The area AL is a range (area) of an angle greater than 0° and less than 180° toward the upstream side (arrow AK side) in the drum rotation direction relative to this half line LN.

[0378] To put it another way, the area AL is located upstream (toward the arrow AK) of the midpoint MA between the center 62a of the drum 62 and the center 30b of the developing roller gear in the drum rotation direction O. The area AL does not extend beyond a straight line (extension line) LA that passes through the center 62a of the drum 62 and the center 30b of the gear portion 30a of the developing roller gear 30.

[0379] Furthermore, when the door 13 is open and the drive transmission member 81 is moved to the drive side, the regulating portion 73j is positioned so as to overlap the gear portion 81a of the drive transmission member 81 in the longitudinal direction. That is, the regulating portion 73j also overlaps the developing roller gear 30 in the longitudinal direction. As shown in FIG. 21 , when the developing roller gear 30 and the regulating portion 73j are projected onto the axis Ax2 of the developing roller gear 30, at least a portion of their projected areas overlap. That is, the regulating portion 73j is located close to the gear portion 81a (gear portion 30a) where the meshing force is generated. Therefore, when the meshing force received by the drive transmission member 81 is supported by the regulating portion 73j, bending of the drive transmission member 81 is suppressed.

[0380] Furthermore, at least a portion of the restricting portion 73j is located outside the coupling protrusion 63b in the axial direction (on the side of the arrow D1 shown in FIG. 21).

[0381] Next, the radial position of the restricting portion 73j with respect to the drum 62 will be described (see FIG. 18(a)).

[0382] Each distance shown below is a distance measured in a direction perpendicular to the axial direction of the drum 62 (radial distance of the drum 62). Let S be the distance from the axis (center 62a) of the drum 62 to the restricting portion 73j. Let U be the radius of the tooth tip of the gear portion 81a of the drive transmission member 81. Let AC be the distance from the center 81j of the drive transmission member 81 to the radially outermost portion of the coupling recess. Let AD be the distance from the center 63d of the drive-side drum flange 63 to the radially outermost portion of the coupling protrusion 63b. Let AA be the distance between the restricting portion 73j and the tooth tip of the gear portion 81a of the drive transmission member 81. Let AB be the amount of misalignment between the coupling protrusion 63b and the coupling recess 81b when the drive transmission member 81 is tilted by the amount of the gap with the restricting portion 73j (when the drive transmission member 81 is tilted and the gear portion 81a comes into contact with the restricting portion 73j) (see FIG. 19(b)).

[0383] Then, the gap AA between the gear portion 81a of the drive transmission member 81 and the restricting portion 73j of the drum bearing 73 is defined as follows: AA=S−U

[0384] In the following description, the distance is measured along the axial direction of the drive transmission member 81 from the fixed end 81c, which is the fulcrum for the inclination of the drive transmission member 81. The axial distance from one end 81c of the drive transmission member 81 to the gear portion 81a is defined as X. Furthermore, the axial distance from one end 81c of the drive transmission member 81 to the coupling recess 81b is defined as W.

[0385] The distance X and the distance W satisfy the relationship W>X. Therefore, when the drive transmission member 81 is tilted by the gap AA between the restricting portion 73j and the gear portion 81a, the amount of misalignment AB is longer than the gap AA and is defined as follows: AB=AA×(W / X).

[0386] Furthermore, the gap between the coupling protrusion 63b of the drive-side drum flange 63 and the coupling recess 81b of the drive transmission member 81 when there is no misalignment is defined as V. Here, the gap V is the smallest value (minimum distance) among the distances between the surfaces of both coupling parts (the distance measured in a direction perpendicular to the axis of the drum 62, i.e., the radial distance).

[0387] When the triangular phases of the couplings are aligned, the shortest gap V is defined as follows: V = AC - AD

[0388] In order for the couplings to engage even when the drive transmission member 81 is tilted by the gap AA and misalignment of the couplings by the amount AB occurs, the gap V between the couplings should satisfy the following: V=AC-AD>AB

[0389] In other words, if the misalignment amount AB is smaller than the shortest gap V between the coupling protrusion 63b and the coupling recess 81b, the coupling protrusion 63b and the coupling recess 81b can tolerate the misalignment amount AB and engage with each other.

[0390] If the phase of the coupling recess 81b relative to the coupling protrusion 63b changes, the shortest gap V between the two coupling portions also changes. In other words, if the phases of the two coupling portions are misaligned, the shortest gap V between the coupling protrusion 63b and the coupling recess 81b becomes smaller than (AC - AD). There may also be cases where V becomes smaller than the amount of misalignment AB.

[0391] However, if there is at least one phase relationship between the two coupling portions that satisfies "V > AB," the coupling protrusion 63b and the coupling recess 81b will engage with each other. This is because the coupling recess 81b comes into contact with the coupling protrusion 63b while rotating. When the coupling recess 81b rotates to an angle that satisfies "V > AB," it can engage (couple) with the coupling protrusion 63b.

[0392] Furthermore, when measuring the distance S from the center 62a of the drum 62 to the restriction portion 73j along the radial direction of the drum 62, the following equation is obtained: S = AA + U. Substituting "AB = AA × (W / X)" and "AA = S - U" into "V > AB," the following equation is obtained: V > (S - U) × (W / X). There must be at least one phase relationship between the coupling protrusion 63b and the coupling recess 81b that satisfies this equation.

[0393] Furthermore, by further modifying the above equation, the condition for the distance S is as follows: S<U+V×(X / W)

[0394] Furthermore, when the drive transmission member 81 rotates, it is desirable that the restricting portion 73j not come into contact with the gear portion 81a, and therefore it is desirable that the restricting portion 73j be separated from the tooth tips of the gear portion 81a. This can be expressed by the equation S>U.

[0395] Summarizing this together with the above relational expression, the following holds: U<S<U+V×(X / W).

[0396] If the cross-sectional shapes of the coupling protrusion 63b and the coupling recess 81b are both substantially equilateral triangles as in this embodiment, the gap V will be at its maximum when the phases of both coupling portions are aligned. The value of V at that time can be substituted into the above equation to find the required range of S.

[0397] The operation of the coupling when engaging will now be described. Before the coupling recess 81b of the drive transmission member 81 engages with the coupling protrusion 63b of the drive-side drum flange 63, a meshing force FD is applied to the drive transmission member 81. As described above, the meshing force FD is a force generated by the meshing of the gear portion 81a of the drive transmission member 81 with the gear portion 30a of the developing roller gear 30.

[0398] The meshing force FD causes the drive transmission member 81 to tilt in the direction FD in which the meshing force is applied, with the drive transmission member bearing 83 as the fulcrum, by the amount of the gap AA between the restricting portion 73j of the drum bearing 73 and the gear portion 81a. The amount of misalignment AB between the coupling recess 81b and the coupling protrusion 63b caused by this tilt becomes smaller than the gap V between the coupling recess 81b and the coupling protrusion 63b at a predetermined phase. As a result, when the drive transmission member 81 rotates and the triangular phases of the coupling recess 81b and the coupling protrusion 63b are aligned, the coupling recess 81b fits into and engages with the coupling protrusion 63b without the end faces of the coupling interfering with each other.

[0399] Here, an example of dimensions that satisfy the above conditional expression when the radius of the drum 62 is 12 mm is shown below.

[0400] In this embodiment, the dimensions of each part of the drive transmission member 81 that is compatible with the drum 62 having a radius of 12 mm are as follows: The distance AC from the center of the coupling recess 81b to the apex of the approximately equilateral triangle of the coupling recess 81b is 6.5 mm, and the radius AE of the inscribed circle of the approximately equilateral triangle of the coupling recess 81b is 4.65 mm. The approximately equilateral triangle of the coupling recess 81b is not a pure equilateral triangle, but has its apex (corner) flattened into an arc shape. The radius AF of the recessed portion 81b3 of the coupling recess is 4.8 mm. The radius U of the tip circle of the gear portion 81a of the coupling recess is 12.715 mm. The distance X from one end 81c to the non-drive side end face 81a1 is 30.25 mm. The distance W from one end 81c to the tip end 81b1 of the coupling recess is 33.25 mm.

[0401] The shortest distance V between the coupling recess 81b and the coupling protrusion 63b satisfies the following relationship: 0<V<1.7

[0402] The lower limit of V occurs when the size of the triangle of the coupling recess 81b is equal to the size of the triangle of the coupling protrusion 63b, and the lower limit of V is "0." On the other hand, the upper limit of V occurs when the distance AC from the center to the vertex of the coupling protrusion 63b is 4.8 mm, which is the radius AF of the cutout portion of the coupling recess 81b. In this case, the gap V (mm) between the coupling protrusion 63b and the coupling recess 81b can be calculated as "1.7 = 6.5 - 4.8."

[0403] Substituting each value and V=1.7 into the formula "U<S<U+V×(X / W)" shown above, we get "12.715<S<14.262" (unit: mm).

[0404] The validity of the above formula will be confirmed using two actual examples.

[0405] First, the first example shows the dimensions when the coupling protrusion 63b is made as large as possible within the range in which it can engage with the coupling recess 81b. In this case, the gap V between the coupling protrusion 63b and the coupling recess 81b is minimized, reducing the allowable tilt of the drive transmission member 81. Therefore, in order to reduce the tilt of the drive transmission member 81, it is necessary to move the restricting portion 73j as close as possible to the normal position of the gear portion 81a.

[0406] On the other hand, the second example shows the dimensions when the coupling protrusion 63b is made as small as possible to allow it to engage with the coupling recess 81b. In this case, the gap V between the coupling protrusion 63b and the coupling recess 81b is maximized, so the coupling protrusion 63b and the coupling recess 81b can engage even if the drive transmission member 81 is relatively tilted. In other words, the restricting portion 73j can relatively tolerate tilt of the drive transmission member 81, so the restricting portion 73j can be relatively far away from the normal position of the gear portion 81a.

[0407] In the first example, the size of the coupling protrusion 63b is maximized, and the radial engagement between the coupling protrusion 63b and the coupling recess 81b (the area where they engage) is maximized. In this case, V (the gap between the couplings) approaches its lower limit (minimum), so S (the distance from the center of the drum 62 to the restriction portion 73j) must approach its lower limit (12.715 mm).

[0408] The distance AD ​​from the center to the apex of the coupling protrusion 63b of the drive-side drum flange 63 is set to 6.498 mm. When the coupling protrusion 63b has a dimension slightly smaller than the 6.5 mm distance from the center of the coupling recess 81b to the apex of the triangle, the radial engagement between the coupling parts is approximately maximized. The radius AG of the inscribed circle inscribed in the triangle that makes up the coupling protrusion 63b of the drive-side drum flange 63 is 4.648 mm. Note that the approximate triangular shape of the coupling protrusion 63b is not a pure equilateral triangle, but rather the apex (corner) is curved into an arc.

[0409] In this case, the distance S from the center 62a of the drum 62 to the regulating portion 73j of the drum bearing is set to 12.716 mm, which is slightly larger than the radius U of the tip circle of the gear portion 81a.

[0410] As a result, the gap AA between the regulating portion 73j of the drum bearing and the gear portion 81a of the drive transmission member is 0.001 mm (= 12.716 - 12.715). Here, the misalignment AB between the coupling portions when the drive transmission member 81 is tilted by the gap AA with the regulating portion 73j is amplified by the difference in the longitudinal positions of the regulating portion 73j and the coupling portion. The misalignment AB is 0.0011 mm (= 0.001 x 33.25 / 30.25). Furthermore, when the coupling portions are in phase, the shortest gap V between the coupling protrusion 63b and the coupling recess 81b is 0.002 mm (the smaller of "6.5 - 6.498" and "4.65 - 4.648").

[0411] Therefore, even if the drive transmission member 81 is tilted by the meshing force, the gap V between the couplings is larger than the amount of misalignment AB between the coupling portions, so engagement is possible.

[0412] As can be seen from the above explanation, it is preferable that the radial distance from the center of the drum 62 to the outermost part of the coupling portion is greater than 4.8 mm, and the radial distance from the center of the drum 62 to the regulating portion 73j is greater than 12.715 mm.

[0413] In the second example, as described above, the size of the coupling protrusion 63b is made as small as possible, and the radial engagement between the coupling protrusion 63b and the coupling recess 81b (the area where they engage) is made as small as possible. In this case, V (the gap between the couplings) approaches its maximum (upper limit), and S (the distance from the center of the drum 62 to the restricting portion 73j) can also take a value close to its upper limit.

[0414] The distance AD ​​between the center and apex of the coupling protrusion 63b of the drive-side drum flange 63 is set to 4.801 mm. This is slightly larger than the 4.8 mm radius of the lightening portion 81b3 of the coupling recess 81b, and is the diameter at which the radial engagement between the couplings is approximately minimized. If the distance AD ​​of the coupling protrusion 63b were shorter than the radius of the lightening portion 81b3, the tip of the protrusion 63b would not engage with the coupling recess 81b, making it impossible to transmit drive force.

[0415] In this case, the radius AG of the triangular inscribed circle of the coupling protrusion 63b is 2.951 mm.

[0416] The distance S from the center 62a of the drum 62 to the restricting portion 73j of the drum bearing is set to 14.259 mm.

[0417] As a result, the gap AA between the restricting portion 73j of the drum bearing 73 and the gear portion 81a of the drive transmission member 81 is 1.544 mm (= 14.259 - 12.715). When the drive transmission member 81 is tilted by the gap AA with the restricting portion 73j, the misalignment amount AB between the coupling portions is amplified by the difference in the longitudinal positions of the restricting portion 73j and the coupling portion, and is 1.697 mm (= 1.544 x 33.25 / 30.25). When the coupling portions are in phase, the gap V between the coupling convex portion 63b and the coupling concave portion 81b is 1.699 mm (the smaller of "6.5 - 4.801" and "4.65 - 2.951"). Therefore, even if the drive transmission member 81 is tilted by the meshing force FD, the gap V between the coupling portions is larger than the misalignment amount AB between the coupling portions, and therefore the coupling convex portion 63b and the coupling concave portion 81b can engage with each other.

[0418] As can be seen from the second example, it is preferable that the radial distance from the center of the drum 62 to the outermost part of the coupling protrusion 63b is greater than 4.8 mm, and the radial distance from the center of the drum 62 to the regulating portion 73j is less than 14.262 mm.

[0419] Combining the first and second examples, in this embodiment, the radial distance S from the center 62a of the drum 62 to the restricting portion 73j of the drum bearing should be greater than 12.715 mm and less than 14.262 mm.

[0420] Next, the arrangement of the coupling protrusion 63b in the longitudinal direction (drum axial direction) will be described. As shown in Figure 17, the drive-side drum flange 63 has a flange 63c. The cleaning frame 71 has a drum regulating rib 71m (drum regulating portion, drum longitudinal position regulating portion, drum axial position regulating portion).

[0421] The drum restriction rib 71m is disposed on the non-driving side of the flange 63c of the driving-side drum flange 63 in the longitudinal direction, and faces the flange 63c with a gap therebetween.

[0422] If the drum 62 moves beyond this gap to the non-drive side, the flange 63c and the drum restricting rib 71m come into contact, restricting the movement of the drum 62. In other words, the drum 62 is configured to not move longitudinally (axially) beyond a certain range. This improves the longitudinal positional accuracy of the coupling protrusion 63b of the drive-side drum flange 63 before it engages with the coupling recess 81b. Therefore, even if the longitudinal movement of the drive transmission member 81 is reduced, the coupling protrusion 63b and the coupling recess 81b can still be engaged. By reducing the longitudinal movement of the drive transmission member 81, the device main body A can be made more compact.

[0423] Next, the arrangement of the gear portion 30a of the developing roller gear 30 in the longitudinal direction (drum axial direction) will be described. As shown in Figure 17, the developing roller gear 30 has a non-drive side end surface 30a2 of the gear portion 30a. The developing container 23 has a developing roller gear regulating rib 23d (gear regulating portion, gear longitudinal position regulating portion, gear axial position regulating portion).

[0424] The developing roller gear restricting rib 23d is disposed on the non-drive side of the non-drive side end face 30a2 of the gear portion 30a in the axial direction, and faces the non-drive side end face 30a2 with a gap therebetween.

[0425] As a result, the developing roller gear restricting rib 23d arranged on the drive side of the cartridge B restricts the developing roller gear 30 from moving longitudinally toward the non-drive side. This improves the axial positional accuracy of the gear portion 30a of the developing roller gear 30 before the gear portion 30a of the developing roller gear 30 meshes with the gear portion 81a of the drive transmission member 81. Therefore, the gear width of the gear portion 30a of the developing roller gear 30 can be reduced. As a result, the cartridge B and the apparatus main body A into which the cartridge B is to be mounted can be made smaller. <Removing the Cartridge>

[0426] Next, removal of the cartridge B from the main assembly A of the apparatus will be described with reference to FIGS.

[0427] 7, when the door 13 is rotated open, the cylindrical cam 86 rotates along the inclined surfaces 86a and 86b via the rotating cam link 85 and moves to the driving side in the axial direction until one end 86c of the cylindrical cam 86 abuts against the end surface 15f of the driving side plate 15. Then, the movement of the cylindrical cam 86 enables the drive transmission member 81 to move to the driving side in the axial direction (the side away from the cartridge B).

[0428] As shown in FIGS. 18A, 18B, and 19A, the radial tooth engagement between the gear portion 81a of the drive transmission member 81 and the gear portion 30a of the developing roller gear 30 is defined as engagement amount AH.

[0429] For the gear portion 81a to disengage from the gear portion 30a, the gear portion 81a must move away from the gear portion 30a by more than the engagement amount AH of both gear portions. Therefore, the regulating portion 73j of the drum bearing 73 is positioned so as not to impede the movement of the drive transmission member 81 when the gear portion 81a disengages from the gear portion 30a. For this reason, the direction in which the gear portion 81a of the drive transmission member 81 moves away from the gear portion 30a of the developing roller gear 30 is indicated by arrow AI, along the line connecting the center 81j of the drive transmission member 81 and the center 30b of the developing roller gear 30. It is preferable not to provide the regulating portion 73j in the direction of arrow AI. In other words, it is preferable not to position the regulating portion 73j so as to straddle the line LA, and to prevent the drive transmission member 81 from coming into contact with the regulating portion 73j when the gear portion 81a disengages from the gear portion 30a.

[0430] When the gear portion 81a disengages from the gear portion 30a, it is desirable that the drive transmission member 81 does not come into contact with the concave circumferential surface 73k of the drum bearing 73. Therefore, when the opening / closing door 13 is open (FIGS. 7(a) and 7(b)), the drive transmission member 81 is retracted to a position where it does not come into contact with the concave circumferential surface 73k of the drum bearing 73.

[0431] 18A, the drive transmission member 81 is retracted until it is no longer coupled to the coupling protrusion 63b. In this state, the tip of the drive transmission member 81 is located at approximately the same position as the tip of the recessed circumferential surface 73k in the longitudinal direction, or further to the left of the tip of the recessed circumferential surface 73k.

[0432] In this state, even if the drive transmission member 81 tilts to release the meshing between the gear portion 81a and the gear portion 30a, the drive transmission member 81 and the recessed circumferential surface 73k will not come into contact with each other.

[0433] It is also possible that the drive transmission member 81 moves a short distance when retracted, and the tip of the drive transmission member 81 in the retracted position is located to the right of the tip of the recessed circumferential surface 73k. In such a case, contact between the drive transmission member 81 and the recessed circumferential surface 73k can be avoided if the following conditions are met.

[0434] The radial distance from the center 62a of the drum 62 to the concave peripheral surface 73k of the drum bearing 73 is defined as Z. The radial distance from the center 81j of the drive transmission member 81 to the outer circumferential surface of the cylindrical portion 81i of the drive transmission member 81 is defined as Y. The radial distance of the gap between the concave peripheral surface 73k and the cylindrical portion 81i is defined as AJ. In this case, the gap AJ satisfies the following formulas: AJ = Z - Y AJ > AH

[0435] That is, a recess is provided around the periphery of the drum 62. The drive transmission member 81 can move within a range where the inner circumferential surface of the recess (recessed circumferential surface 73k) does not come into contact with the gear portion 81a.

[0436] The radial position of the concave peripheral surface 73k of the drum bearing 73 may be determined as long as the distance Z from the center 62a of the drum 62 satisfies the following equation: Z>AH+Y

[0437] With the above-described configuration, when the cartridge B is removed from the main assembly A of the apparatus, the drive transmission member 81 can be tilted in the separating direction AD by an amount equal to or greater than the amount of engagement AH between the gear portion 81a of the drive transmission member 81 and the gear portion 30a of the developing roller gear 30. Then, the meshing between the gear portion 81a of the drive transmission member 81 and the gear portion 30a of the developing roller gear 30 is released, allowing the cartridge B to be smoothly removed from the main assembly A of the apparatus.

[0438] As described above, the drive transmission member 81 moves in a direction approaching the coupling portion on the cartridge side due to the thrust force generated by the meshing of the helical gears.

[0439] Furthermore, the drive transmission member 81 moves (tilts) due to the force generated by the meshing of the gears, but the amount of this movement (tilt) is regulated by a regulating portion provided on the cartridge side, thereby ensuring engagement (coupling) between the drive transmission member 81 and the coupling portion on the cartridge side and ensuring drive transmission.

[0440] Furthermore, by providing a gap that allows the drive transmission member 81 to move radially beyond the gear meshing height, the gears are smoothly disengaged when the cartridge B is removed from the main assembly of the apparatus. In other words, the cartridge can be easily removed.

[0441] The functions, materials, shapes, relative arrangements, etc. of the components described in the above-mentioned embodiment and each modification are not intended to limit the scope of the present invention unless otherwise specified. The same applies to the embodiments described below.

[0442] Next, Example 2 will be described below with reference to Figures 23 to 38. In particular, among the elements disclosed in this Example, those corresponding to the members described in Example 1 will be given the same names as the members in Example 1, and only the differences from Example 1 will be described.

[0443] In this embodiment, the direction along the rotation axis Ax1 of the drum 62 is defined as a longitudinal direction D202. The longitudinal direction D202 is the direction of the rotation axis of the drum 62 (axial direction).

[0444] As in the first embodiment, the side of the drum 62 on which the driving-side drum flange 263 (see FIG. 24(b)) is located is referred to as the driving side or driving-side side of the cartridge. The driving side can also be considered as the end of the cartridge in the axial direction of the drum 62.

[0445] The side opposite the drive side in the axial direction of the drum 62 is referred to as the non-drive side or the side of the non-drive side of the cartridge. One of the drive side and the non-drive side of the cartridge may be referred to as one side of the cartridge, or the first side or first side of the cartridge. The other of the drive side and the non-drive side of the cartridge may be referred to as the other side, or the second side or second side.

[0446] Furthermore, one of the ends of the drum 62 may be referred to as the first end or first end. Furthermore, the other end may be referred to as the second end or second end. For example, when the drive side end of the drum 62 is referred to as the first end or first end, the non-drive side end of the drum 62 is referred to as the second end or second end. The second end is the end of the drum 62 located opposite the first end. The drive side end of the drum 62 is the end of the drum 62 where the drive side drum flange 263 (see FIG. 24(b)) is provided. In other words, the drum 62 receives a driving force from the drive side end.

[0447] The direction from the non-drive side to the drive side is the direction of arrow E20, and the direction from the drive side to the non-drive side is the direction of arrow E26.

[0448] First, the cartridge configuration of this embodiment will be described with reference to Figures 23 and 24. Figure 23 is a perspective view of cartridge B. Figure 24 is a diagram showing the drive transmission configuration of cartridge B in this embodiment for the purpose of explanation. (a) is a view taken along a direction perpendicular to the rotation axis of the drum 62, and (b) is a perspective view. Note that Figure 24 does not show the rack gear mechanism 290 and drum bearing 73. As shown in Figure 23, cartridge B in this embodiment is composed of a cleaning unit 260 and a developing unit 220, similar to embodiment 1. The developing unit 220 also has a rack gear mechanism 290.

[0449] 24, the drive-side drum flange 263 has a gear portion 263e on the side closer to the drum 62 in the axial direction of the drum 62. The developing roller gear 230 has a gear portion 230a and is supported so as to rotate integrally with the support shaft 32a of the developing roller 32. The support shaft 32a of the developing roller 32 protrudes further toward the drive side than the developing roller gear 230 in the longitudinal direction D202.

[0450] Furthermore, the gear portion 230a of the developing roller gear 230 is disposed in mesh with the gear portion 263e of the driving side drum flange 263. That is, the driving force of the driving side drum flange 263 is transmitted to the developing roller 32 via the developing roller gear 230. In other words, the developing roller 32 is driven by driving the driving side drum flange 263. In this embodiment, the driving force is transmitted to the developing unit 220 by the gear portion 263e of the driving side drum flange 263, but the driving force may also be transmitted to the developing unit 220 from the non-driving side drum flange. This configuration will be described later in Modification 2 of Embodiment 7 with reference to FIG. 101. <Rack Gear Mechanism>

[0451] Next, the configuration of the rack gear mechanism 290 will be described with reference to Fig. 25. Fig. 25 is an exploded perspective view of the rack gear mechanism 290. (a) is a view seen from the non-drive side, and (b) is a view seen from the drive side.

[0452] In this embodiment, the rack gear mechanism 290 is provided on the drive side of the cartridge as part of the configuration of the developing unit 220 (see Figure 28(b)). As shown in Figure 25, the rack gear mechanism 290 is made up of a drive-side developing side member 226, a rack gear 291, a tension spring 292, a locking member 293, a torsion coil spring 294, a rotating member 295, a support member 296, a pressed member 297, and an initialization spring 298. The rack gear 291 is sometimes simply called a rack.

[0453] As will be described in detail later, the rack gear 291 is a gear configured to engage with a helical gear on the outside of the cartridge, i.e., to mesh with the gear portion 81a of the drive transmission member 81. A rack gear mechanism 290 including the rack gear 291 is disposed on the drive side of the cartridge. In other words, in the axial direction of the drum 62, the coupling portion (coupling protrusion 263a) and the rack gear mechanism 290 are located on the same side of the cartridge.

[0454] The components of the rack gear mechanism 290 will be described below.

[0455] The drive side developing side member 226 has, as components related to the rack gear mechanism 290, a rail portion 226a, a regulating portion 226b, a slide surface 226c, a retaining portion 226f, a hole portion 226d, a spring hook portion 226e, a spring seat surface 226h, a notch 226g, and a guide surface 226i.

[0456] The rail portion 226a extends in a predetermined first movable direction D200, and one end thereof is defined as an end portion 226a1.

[0457] The restricting portion 226b is provided on the opposite side to the end portion 226a1 of the rail portion 226a. The restricting portion 226b has a shape in which a part of the restricting portion 226b protrudes beyond the rail portion 226a in a direction perpendicular to the first movable direction D200.

[0458] The slide surface 226c is a surface perpendicular to the first movable direction D200. If a direction perpendicular to the first movable direction D200 and the longitudinal direction of the cartridge is defined as a second movable direction D201, the slide surface 226c extends in the second movable direction D201. The slide surface 226c is a pair of surfaces facing each other in the first movable direction D200, and is located between the end 226a1 of the rail portion 226a and the restricting portion 226b.

[0459] The retaining portion 226f is provided between the pair of slide surfaces 226c. The retaining portion 226f has a first hole 226f1 and a second hole 226f2 arranged from the side closer to the rail portion 226a in the second movable direction D201. The width of the first hole 226f1 and the second hole 226f2 in the first movable direction D200 is larger for the first hole 226f1 than for the second hole 226f2. Furthermore, the retaining portion 226f has a pair of retaining walls 226f3 adjacent to the second hole 226f2 in the first movable direction D200.

[0460] The hole portion 226d is provided closer to the end portion 226a1 of the rail portion 226a than the slide surface 226c in the first movable direction D200.

[0461] The spring hook portion 226e is provided on the downstream side of the hole portion 226d in the direction of arrow E22, that is, on the side away from the rail portion 226a, in the first movable direction D200.

[0462] The spring seat surface 226h is a surface of the driving side developing side member 226 located on the most downstream side in the cartridge mounting direction (see arrow C in FIG. 8).

[0463] The notch 226g is provided on the non-drive side of the spring seat surface 226h in the longitudinal direction D202.

[0464] The guide surface 226i is a surface that is adjacent to the notch 226g and extends upstream in the cartridge mounting direction.

[0465] The rack gear 291 has a rectangular parallelepiped shape and is composed of a gear portion 291a, a guided groove 291b, a groove portion 291c, a spring hook portion 291d, and an abutment surface 291e. The longitudinal direction of the rack gear 291 coincides with the first movable direction D200. The rack gear 291 is a gear that can move linearly along the first movable direction D200.

[0466] The gear portion 291a is a portion that has at least one gear tooth. The gear portion 291a in this embodiment has a plurality of gear teeth. The gear teeth are arranged in the first movable direction D200 of the rack gear 291. As will be described in detail later, the gear portion 291a in this embodiment is a component that corresponds to the gear portion 30a in the first embodiment (see FIG. 9). At least a portion of the gear portion 291a is exposed to the outside of the cartridge in order to mesh with the gear portion 81a of the drive transmission member 81. More specifically, the exposed portion of the gear portion 291a faces the side on which the axis Ax1 of the drum 62 is located (see FIG. 23).

[0467] The guided groove 291b is a T-shaped groove that penetrates in the first movable direction D200 and is parallel to the arrangement direction of the gear portions 291a. The guided groove 291b is shaped so that it can move only in the first movable direction D200 by the rail portion 226a of the driving-side developing side member 226.

[0468] The groove portion 291c is a groove that faces the gear portion 291a in the second movable direction D201. Of the surfaces that form the groove portion 291c, the surface parallel to the first movable direction D200 is a restricting surface 291c1, and of the two surfaces that are perpendicular to the second movable direction D201, the surface closer to the gear portion 291a is a locking surface 291c2. Furthermore, a corner formed on the opposite side of the locking surface 291c2 from the restricting surface 291c1 in the second movable direction D201 is a pressed portion 291c3.

[0469] The spring hook portion 291d is provided on the opposite side of the groove portion 291c from the gear portion 291a in the first movable direction D200.

[0470] The tension spring 292 has spring hooks 292a at both ends in the extension direction. The spring hooks 292a are shaped so as to be attachable to the spring hooks 226e of the driving-side developing-device side member 226 and the spring hooks 291d of the rack gear 291.

[0471] The locking member 293 has a flat plate shape and is composed of a pressing portion 293 a, a regulated surface 293 b, a first cylindrical portion 293 c, a second cylindrical portion 293 d, a gap 293 e, a retaining protrusion 293 f, and a guided surface 293 g. The guided surfaces 293 g are a pair of opposing surfaces, and the extension direction thereof coincides with the second movable direction D201.

[0472] As shown in the figure, the pressing portion 293a is inclined with respect to one guided surface 293g.

[0473] The regulated surface 293b is a surface that extends from the pressing portion 293a in the first movable direction D200 toward the guided surface 293g.

[0474] The first cylindrical portion 293c and the second cylindrical portion 293d are protrusions provided to extend in the longitudinal direction D202 in a direction away from the rack gear 291. Furthermore, the first cylindrical portion 293c and the second cylindrical portion 293d are arranged in this order in the second movable direction D201 in a direction away from the regulated surface 293b. Furthermore, a gap 293e is formed between the first cylindrical portion 293c and the second cylindrical portion 293d.

[0475] The retaining protrusion 293f is a T-shaped protrusion that extends in the opposite direction from the first cylindrical portion 293c and the second cylindrical portion 293d in the longitudinal direction D202. The retaining protrusion 293f has an arm portion 293f1 and a retaining portion 293f2, and the width of the arm portion 293f1 in the second movable direction D201 is smaller than that of the retaining portion 293f2. Furthermore, in the longitudinal direction D202, the retaining portion 293f2 is located farther from the first cylindrical portion 293c and the second cylindrical portion 293d than the arm portion 293f1.

[0476] The torsion coil spring 294 is composed of an actuated arm 294a, an acting arm 294b, and an inner diameter portion 294c. A state in which no load is acting on the actuated arm 294a and the acting arm 294b is referred to as a free state. When viewed from the longitudinal direction D202 of the actuated arm 294a and the acting arm 294b, the side in which the free ends of the actuated arm 294a and the acting arm 294b approach each other from the free state is referred to as a closing direction, and the side in which they move apart is referred to as an opening direction. If the actuated arm 294a and the acting arm 294b are continuously moved in the closing direction, their free ends will meet and then move apart. The case in which the free ends move apart at this time is also referred to as a closing direction.

[0477] The rotation member 295 is composed of a first cylindrical portion 295a, a second cylindrical portion 295b, a gap 295c, a first pressed surface 295d, a second pressed surface 295e, a gap 295f, and a shaft portion 295g.

[0478] The shaft portion 295g is a cylinder extending in the longitudinal direction D202, and serves as the rotation axis of the rotation member 295. The rotation axis of the rotation member 295 is defined as a rotation axis line Ax20.

[0479] The first cylindrical portion 295a and the second cylindrical portion 295b are protrusions that extend in the longitudinal direction D202 toward the rack gear 291. If the clockwise direction about the rotation axis Ax20 as viewed from the direction in which the first cylindrical portion 295a and the second cylindrical portion 295b protrude is defined as the rotation direction Q20, the first cylindrical portion 295a is located downstream and the second cylindrical portion 295b is located upstream with respect to the rotation direction Q20. A gap 295c is defined between the first cylindrical portion 295a and the second cylindrical portion 295b.

[0480] The first pressed surface 295d and the second pressed surface 295e are disposed at positions spaced a certain distance apart in the radial direction centered on the rotation axis Ax20. In addition, with respect to the rotation direction Q20, the first pressed surface 295d faces downstream, and the second pressed surface 295e faces upstream. A gap 295f is formed between the first pressed surface 295d and the second pressed surface 295e.

[0481] The support member 296 is composed of a hole 296a, a developing roller support hole 296b, and a guide surface 296c, and is a member that is fixed to the drive-side developer side member 226 when the rack gear mechanism 290 is assembled. In the longitudinal direction D202, the hole 296a and the guide surface 296c are provided on one end side, and the developing roller support hole 296b is provided on the other end side. Here, the one end side is the side where the hole 226d of the drive-side developer side member 226 is provided.

[0482] The hole 296a is provided so as to be coaxial with the hole 226d of the driving side developing member 226 when the rack gear mechanism 290 is assembled. The assembly of the rack gear mechanism 290 will be described later.

[0483] The guide surface 296c is provided so as to face and be parallel to the guide surface 226i of the driving-side developing side member 226 when the rack gear mechanism 290 is assembled.

[0484] The pressed member 297 is L-shaped and is composed of a pressed surface 297a, a spring seat 297e, a guided surface 297c, a notched portion 297d, and a cylindrical portion 297b.

[0485] The pressed surface 297a is a surface extending in the longitudinal direction D202. A spring seat 297e is provided on the surface opposite to the pressed surface 297a.

[0486] The guided surfaces 297c are a pair of surfaces extending vertically from the spring seat 297e, and are arranged so as to be parallel to the guide surface 226i of the driving side developing side member 226 and the guide surface 296c of the support member 296 when the rack gear mechanism 290 is assembled.

[0487] A notch 297d is provided in a gap 297d1 between the pair of guided surfaces 297c, and has an inlet 297d2 that is open on the side away from the pressed surface 297a.

[0488] The columnar portion 297b is a protrusion extending in the longitudinal direction D202.

[0489] The initialization spring 298 is a compression spring (compression coil spring), but other elastic members may be used instead of such a spring. <Assembly of the rack gear mechanism>

[0490] Next, a method for assembling the rack gear mechanism 290 will be described with reference to Figures 26 to 29. Figures 26 and 27 are diagrams showing a method for assembling the rack gear mechanism 290. Assembly is performed in the order of Figures 26(a), (b), and (c), and Figure 27(a), (b), and (c). Figure 28 is a diagram showing a method for assembling the rack gear mechanism 290 to the developing unit 220. (a) shows the state before assembly, and (b) shows the state after assembly. Figure 29 is a diagram showing the arrangement of the rack gear 291 of the rack gear mechanism 290. (a) is a view taken along a direction perpendicular to the rotation axis of the drum 62, and (b) is a cross-sectional view taken along the X200-X200 line in (a).

[0491] First, as shown in FIG. 26A , the locking member 293 is assembled to the drive-side developer-side member 226. The locking member 293 is assembled in the direction of arrow E20 along the longitudinal direction D202 to allow the retaining portion 293f2 to pass through the first hole 226f1 of the drive-side developer-side member 226. The locking member 293 moves in the direction of arrow E21 along the second movable direction D201 after the retaining portion 293f2 has completely passed through the first hole 226f1. Then, as the arm portion 293f1 passes through the second hole 226f2, the movement of the locking member 293 in the longitudinal direction D202 is restricted by the retaining wall 226f3. Furthermore, the guided surface 293g of the locking member 293 is sandwiched between the sliding surface 226c, restricting movement in the first movable direction D200. As a result, the locking member 293 is supported by the driving-side developing-device side member 226 so as to be movable only in the second movable direction D201.

[0492] Next, as shown in FIG. 26( b), the rack gear 291 is assembled to the drive-side developer-side member 226. The rack gear 291 is assembled to the rail portion 226a in the direction of arrow E22 along the first movable direction D200 so that the guided groove 291b is inserted from the end 226a1 of the rail portion 226a. The guided groove 291b of the rack gear 291 is supported by the rail portion 226a, and movement of the rack gear 291 in the second movable direction D201 and the longitudinal direction D202 is restricted. As a result, the rack gear 291 is supported by the drive-side developer-side member 226 so as to be movable only in the first movable direction D200.

[0493] Next, the spring hook portion 292a of the tension spring 292 is assembled to the spring hook portion 291d of the rack gear 291 and the spring hook portion 226e of the drive-side developer side member 226. As shown in Figure 26(c) , the rack gear 291 is biased in the direction of arrow E22 by a force F20 from the tension spring 292. The abutment surface 291e of the rack gear 291 is brought into contact with the regulating portion 226b of the drive-side developer side member 226 by the force F20, and movement of the rack gear 291 in the direction of arrow E22 is restricted.

[0494] Next, as shown in Figure 27(a), the torsion coil spring 294 and the rotating member 295 are assembled to the drive-side developer-side member 226. First, the shaft portion 295g of the rotating member 295 is inserted into the inner diameter portion 294c of the torsion coil spring 294, with the actuated arm 294a positioned in the gap 295c. The rotating member 295 is assembled in the direction of arrow E20 along the longitudinal direction D202, and the shaft portion 295g is rotatably supported in the hole 226d. At this time, the torsion coil spring 294 is assembled so that the actuating arm 294b is positioned in the gap 293e of the locking member 293.

[0495] Next, as shown in FIG. 27B , the pressed member 297 and the initialization spring 298 are assembled to the drive-side developer-side member 226. The pressed member 297 is inserted into the notch 226g from the direction of arrow E24 along the guide surface 226i. At this time, the pressed member 297 is assembled so that the cylindrical portion 297b of the pressed member 297 is positioned in the gap 295f of the rotating member 295. Furthermore, the pressed member 297 passes through the shaft portion 295g of the rotating member 295 from the entrance portion 297d2 to the gap 297d1. Furthermore, the guided surface 297c of the pressed member 297 faces the guide surface 226i. Thereafter, the initialization spring is compressed and provided between the spring seat 297e of the pressed member 297 and the spring seat surface 226h of the drive-side developer-side member 226.

[0496] Next, as shown in FIG. 27C , the support member 296 is assembled to the drive-side developer side member 226. The support member 296 is assembled in the direction of arrow E25 along the longitudinal direction D202, and the shaft portion 295g of the rotation member 295 is inserted into the hole 296a. The guide surface 296c is fixed to the drive-side developer side member 226 by adhesive or the like, while supporting the guided surface 297c of the pressed member 297. At this time, the shaft portion 295g of the rotation member 295 is rotatably supported by the hole 226d of the drive-side developer side member 226 and the hole 296a of the support member 296. The guided surface 297c of the pressed member 297 is supported by the guide surface 226i of the drive-side developer side member 226 and the guide surface 296c of the support member 296 so as to be movable in a predetermined direction, which is defined as a third movable direction D203. Furthermore, the movement of the rotating member 295, the torsion coil spring 294, and the pressed member 297 in the longitudinal direction D202 is restricted by the driving-side developer-side member 226 and the support member 296. As described above, the rotating member 295 is supported by the driving-side developer-side member 226 and the support member 296 so as to be rotatable about the rotation axis Ax20. Similarly, the pressed member 297 is supported by the driving-side developer-side member 226 and the support member 296 so as to be movably in the third movable direction D203.

[0497] Through the above steps, the rack gear mechanism 290 is assembled.

[0498] Next, the rack gear mechanism 290 is assembled to the developing unit 220. As shown in Figure 28(a) , the rack gear mechanism 290 is assembled in the direction of arrow E26 along the longitudinal direction D202 so that the support shaft 32a of the developing roller 32 is inserted into the support hole 296b of the support member 296. Thereafter, the rack gear mechanism 290 is fixed to the developing unit 220 with screws or the like (see Figure 28(b) ).

[0499] Finally, the developing unit 220 to which the rack gear mechanism 290 is attached and the cleaning unit 260 are assembled, but since this is the same as in the first embodiment, the description thereof will be omitted.

[0500] Here, the range in which the rack gear 291 of the rack gear mechanism 290 is located will be described with reference to Figure 29. Since the rack gear 291 is a component corresponding to the developing roller gear 30 of the first embodiment (see Figure 9, etc.), the preferred location of the rack gear 291 conforms to the preferred range of the developing roller gear 30. However, there are differences between them, which will be described in particular detail below.

[0501] As will be described in detail later, the rack gear 291 is a movable component. Unless otherwise specified, the following description is based on the premise that the cartridge is in its initial position before it is mounted in the main body of the apparatus, i.e., the rack gear 291 is in a position for engaging with the drive transmission member 81.

[0502] In FIG. 29(a), for the sake of explanation, only the drum 62 and the drive-side drum flange 263 are shown as components constituting the cleaning unit 260. Similarly, FIG. 29(b) shows only the drum 62, the developing roller 32, and the rack gear 291. Furthermore, in addition to the arrangement of the rack gear 291 in this embodiment, for the sake of explanation, FIG. 29(b) also illustrates a state in which the rack gear 291 is arranged in the positive and negative directions of angle K20, which will be described later. The positive angle is angle K20U, and the negative angle is angle K20L. FIG. 29(b) corresponds to a view of the cartridge as seen along the axis Ax1 of the photosensitive drum. In other words, FIG. 29(b) corresponds to a view of the cartridge as seen in the axial direction of the photosensitive drum. In other words, FIG. 29(b) corresponds to a view of some components of the cartridge projected onto a plane perpendicular to the axis Ax1 of the photosensitive drum.

[0503] 29( a), in the longitudinal direction D202, the gear portion 291a of the rack gear 291 is located on the side indicated by the arrow E20 relative to the tip end 263b1 of the coupling protrusion 263b of the drive-side drum flange 263. In other words, the gear portion 291a of the rack gear 291 is located on the longitudinal outer side relative to the tip end 263b1 of the coupling protrusion 263b of the drive-side drum flange 263. In other words, the gear portion 291a of the rack gear 291 is located on the side farther from the non-drive side of the cartridge B than the tip end 263b1 of the coupling protrusion 263b of the drive-side drum flange 263.

[0504] In other words, the gear portion 291a is located farther from the non-drive side of the cartridge B and the non-drive side end of the drum 62 than the tip portion 263b1. In other words, the distance from the non-drive side end of the drum 62 to the gear portion 291a is longer than the distance from the non-drive side end of the drum 62 to the tip portion 263b1. However, these distances are measured in a direction parallel to the axis Ax1 of the photosensitive drum.

[0505] The distance between the gear portion 291a and the tip end 263b1 measured along the longitudinal direction D202 is defined as distance L20. Distance L20 can be set at any position on the gear portion 291a. In this case, distance L20 is set in the range of 0 to 12 mm, but is more preferably set in the range of 3 to 9 mm. In this embodiment, it is set to 5.5 mm. Note that the range of distance L20 may be further increased depending on the tooth width of the gear portion 291a and the configuration of the drive-side drum flange 263.

[0506] In this embodiment, the entire area of ​​the gear portion 291a is located closer to the direction of the arrow E20 than the tip portion 263b1, but the gear portion 291a may be partially located closer to the direction of the arrow E20 than the tip portion 263b1. In other words, at least a part of the gear portion 291a is located closer to the direction of the arrow E20 than the tip portion 263b1.

[0507] 29( b), a direction perpendicular to the first movable direction D200 is defined as an orthogonal direction D207. The arrow indicating the orthogonal direction D207 is a straight line perpendicular to the movement direction of the rack gear 291 (first movable direction D200) and a straight line passing through each tooth tip of the rack gear 291. This arrow also passes through the gear portion 291 a of the rack gear 291 and extends in a direction away from the rotation axis Ax1 of the drum 62.

[0508] 29(b), distance L21 is the distance measured along the orthogonal direction D207 from the rotation axis Ax1 of the drum 62 to a line passing through the tips of the teeth of the gear portion 291a of the rack gear 291. This distance L21 is the distance measured along a direction orthogonal to the rotation axis Ax1 from the rotation axis Ax1 of the drum 62 to a line passing through the tips of the teeth of the gear portion 291a.

[0509] In this case, it is desirable that the distance L21 be in the range of 90% to 120% of the radius of the drum 62, and more preferably 90% to 110%. This is to ensure that the gear portion 291a meshes with the gear portion 81a of the drive transmission member 81.

[0510] In this embodiment, the radius of the drum 62 is 12 mm, as in the first embodiment, and the distance L21 is set within a range of 11.165 mm to 12.84 mm. In other words, the distance L21 from the axis of the drum 62 to the tip of the gear tooth of the gear portion 291 a is within a range of 93% to 107% of the drum radius.

[0511] Furthermore, the distance measured along a direction perpendicular to the rotation axis Ax1 from the rotation axis Ax1 of the drum 62 to the tip of the tooth of the gear portion 291a that is closest to the rotation axis Ax1 is defined as L22.

[0512] Like L21, L22 is preferably in the range of 90% to 120% of the radius of the drum 62, more preferably 90% to 110%. In this embodiment, it is set to the range of 93% to 107%.

[0513] Note that the gear portion 291a is at least partially exposed so as to face the drum axis Ax1 in order to mesh with the drive transmission member 81 (see FIGS. 29(a) and 29(b)). An open space is provided between the gear portion 291a and the drum axis Ax1 so that the drive transmission member 81 can be disposed between the gear portion 291a and the drum axis Ax1.

[0514] Furthermore, an angle K20 is defined as the angle between a line extending from the rotation axis Ax1 of the drum 62 to pass through the rotation axis Ax2 of the developing roller 32 and the orthogonal direction D207. The downstream direction of the rotation of the drum 62 is defined as the positive direction of the angle K20.

[0515] In this embodiment, the angle K20 is set to 0°, so the orthogonal direction D207 coincides with the reference line. See angles K20U and K20L.

[0516] The positive direction of the angle is the downstream direction of the rotation of the drum 62. That is, the positive side of the angle K20 is the downstream side in the direction of arrow R, which is the rotation direction of the drum 62, and the negative side is the upstream side in the direction of arrow R. In this case, it is preferable that the rack gear 291 is disposed so that the angle K20 is in the range of -75° to 50°.

[0517] The lower limit of K20 is set from the viewpoint of ensuring more reliable engagement between the drive transmission member 81 and the rack gear 291, and from the viewpoint of preventing the rack gear 291 and the surrounding cartridge structures from interfering with the image forming apparatus main body A. Therefore, it is more preferable that the angle K20 be −50° or more, and even more preferable that it be −35° or more.

[0518] Furthermore, with regard to the upper limit of K20, it is more preferable that angle K20 be 45° or less, and even more preferable that angle K20 be 30° or less, from the viewpoint of ensuring more reliable engagement between the drive transmission member 81 and the rack gear 291 and preventing the rack gear 291 and the surrounding cartridge structures from interfering with the image forming apparatus main body A.

[0519] The upper and lower limits of the above-mentioned angles may be selected in appropriate combination depending on the configuration of the apparatus main body A and the cartridge.

[0520] In this way, the preferred range of the angle K20 is appropriately set depending on the configuration of the image forming apparatus main body A to which this embodiment is applied, which will be described later.

[0521] As described above, the reference line is the straight line connecting the rotational axis Ax1 of the drum 62 and the rotational axis Ax2 of the developing roller 32. The angle formed by the straight line extending from the rotational axis Ax1 of the drum 62 and passing through the tip of the teeth of the gear portion 291a of the rack gear 291 with respect to this reference line is defined as angle K21 (see FIG. 29).

[0522] The angle K21 is positive when directed downstream in the direction of arrow R, which is the rotation direction of the drum 62, and negative when directed upstream in the direction of arrow R. In this case, the rack gear 291 is preferably positioned so that the angle K21 is between −75° and 50°, both inclusive. This is a preferable condition for the gear portion 81a of the drive transmission member 81 (see FIG. 13) and the gear portion 291a of the rack gear 291 to mesh with each other.

[0523] Regarding the lower limit of K21, from the viewpoint of ensuring more reliable meshing between the drive transmission member 81 and the rack gear 291, it is more preferable that the angle K21 be equal to or greater than -50°, and even more preferable that the angle K21 be equal to or greater than -35°.

[0524] Furthermore, with regard to the upper limit of K21, it is more preferable that the angle K21 be 45° or less, and even more preferable that it be 30° or less, from the viewpoint of ensuring more reliable engagement between the drive transmission member 81 and the rack gear 291 and preventing the rack gear 291 and the surrounding cartridge structures from interfering with the apparatus main body.

[0525] The upper and lower limits of the angle may be selected in appropriate combination depending on the configuration of the apparatus main body A and the cartridge. In this embodiment, K21 is set to be between -35° and 45°.

[0526] It is preferable that the angle K21 of at least one tooth of the gear portion 291a of the rack gear 291 be arranged so as to fall within the above-mentioned preferred range. However, it is more preferable that the angle K21 formed by the straight line extending from the rotation axis Ax1 toward the tip of the nearest tooth of the rack gear and the reference line be within the above-mentioned preferred range.

[0527] In this embodiment, the rack gear mechanism 290 is provided in the developing unit 220, but it may be provided in the cleaning unit 260 depending on the settings of the angle K20, the angle K21, the distance L20, and the distance L21. <Operation of the rack gear mechanism>

[0528] Next, the operation of the rack gear mechanism 290 will be described with reference to FIG.

[0529] 30 is an operation diagram of the rack gear mechanism 290, with (a) and (c) showing the X201-X201 cross section of FIG. 29(a), and (b) and (d) showing the X202-X202 cross section. Also, (a) and (c) show the standby state (non-operating state) of the rack gear mechanism 290, and (b) and (d) show the operating state of the rack gear mechanism 290. Note that some members are shown hatched for ease of explanation.

[0530] First, the standby state (non-operating state) of the rack gear mechanism 290 will be described with reference to Figures 30(a) and (c). As shown in Figure 30(a), the pressed member 297 is urged in the direction of arrow E25 along the third movable direction D203 by the urging force F21 of the initialization spring 298, and is positioned at a first position protruding in the direction of arrow E25. Furthermore, the cylindrical portion 297b abuts against the first pressed surface 295d of the rotating member 295, applying a force F22 to the first pressed surface 295d. A moment M21 due to the force F22 is generated in the rotating member 295, and the rotating member 295 is urged in the rotational direction Q21 around the rotation axis Ax20.

[0531] As shown in FIG. 30( c), the first cylindrical portion 295a of the rotating member 295 is biased in a rotational direction Q21 centered on the rotation axis Ax20. The acted arm 294a of the torsion coil spring 294 abuts against the first cylindrical portion 295a of the rotating member 295 and receives a force F23. As a result of receiving this force F23, a moment M23 is generated in the torsion coil spring 294 about the rotation axis Ax1. This moment M23 biases the torsion coil spring 294 in the rotational direction Q23 centered on the rotation axis Ax21. The acting arm 294b of the torsion coil spring 294 abuts against the second cylindrical portion 293d of the locking member 293, and applies a force F24 to the second cylindrical portion 293d. The acting arm 294b abuts against the second cylindrical portion 293d of the locking member 293.

[0532] With this configuration, the locking member 293 is biased in the direction of arrow E21. At this time, the angle between the actuated arm 294a and the acting arm 294b of the torsion coil spring 294 is set in a direction slightly wider than in the free state. In other words, the actuated arm 294a and the acting arm 294b of the torsion coil spring 294 attempt to return to their closed position. A force F24 on the locking member 293 is maintained. This state is referred to as the standby state of the rack gear mechanism 290. As will be described in detail later, the standby state is a non-operating state in which the locking member 293 of the rack gear mechanism 290 is not operated.

[0533] Next, the operating state of the rack gear mechanism 290 will be described with reference to Figures 30(b) and (d). When the cartridge B is installed in the image forming apparatus main body A, the pressed surface 297a of the pressed member 297 comes into contact with a part of the image forming apparatus main body A and is pressed in the direction of arrow E24. In this embodiment, that part of the image forming apparatus main body A is the contact portion 15m of the drive side plate 15 (see Figure 31(a)). When the pressed member 297 moves in the direction of arrow 24, the second pressed surface 295e of the rotating member 295 is pressed against the cylindrical portion 297b, and the rotating member 295 rotates in the rotation direction Q20 around the rotation axis Ax20 (see Figures 30(b) and 30(d)).

[0534] In this state, the pressed member 297 is urged by the external force F25 in the direction of the arrow E24 along the third movable direction D203, and moves to the second position in the direction of the arrow E24. In addition, the cylindrical portion 297b of the pressed member 297 abuts against the second pressed surface 295e of the rotating member 295, and applies a force F26 to the second pressed surface 295e of the rotating member 295.

[0535] A moment M22 is generated in the rotating member 295 by the force F26, causing the rotating member 295 to rotate in a rotational direction Q20 about the rotational axis Ax20. As shown in Figure 30(d) , as the rotating member 295 rotates in the rotational direction Q20, the second cylindrical portion 295b comes into contact with the acted arm 294a of the torsion coil spring 294, applying a force F200. The torsion coil spring 294 is spring-charged by the force F200, generating a moment M24. If the rotational axis Ax22 of the torsion coil spring 294 at this time is taken as the rotational axis Ax22, the torsion coil spring 294 is biased in the rotational direction Q24 about the rotational axis Ax22.

[0536] The acting arm 294b of the torsion coil spring 294 abuts against the first cylindrical portion 293c of the locking member 293, and applies a force F27 to the first cylindrical portion 293c. The force F27 urges the locking member 293 in the direction of arrow E27, and the regulated surface 293b abuts against the rack gear 291. At this time, the angle between the actuated arm 294a and the acting arm 294b of the torsion coil spring 294 is closer than in the free state. In other words, the actuated arm 294a and the acting arm 294b of the torsion coil spring 294 attempt to return to their original position in the opening direction.

[0537] As a result, the torsion coil spring 294 maintains a state in which the operating arm 294b biases the lock member 293 with a force F27 in the direction of arrow E27 along the second movable direction D201. This state is referred to as the operating state of the rack gear mechanism 290.

[0538] As will be described in detail later, the operating state is a state in which the locking member 293 is operable. In other words, when the rack gear mechanism 290 is in the operating state, after the rack gear 291 moves, the rack gear 291 is locked by the locking member 293 and does not return to its original position.

[0539] When the cartridge B is removed from the image forming apparatus main body A in this state, as shown in Figures 30(a) and (c), the pressed member 297 moves in the direction of arrow E25 due to the biasing force F21 of the initialization spring 298. The first pressed surface 295d of the rotating member 295 is pressed by the cylindrical portion 297b, and the rotating member 295 rotates in the rotation direction Q21 about the rotation axis Ax20. In other words, the rack gear mechanism 290 returns to the standby state (non-operating state) shown in Figure 30(a).

[0540] As will be described in detail later, the standby state is a state in which the locking member 293 is not activated. In other words, when the rack gear mechanism 290 returns to the standby state, the rack gear 291 is no longer locked by the locking member 293, and therefore the rack gear 291 can return to its original position.

[0541] The locking member 293 may be simply called a lock, and the pressed member 297 may be called an operating portion. The pressed member 297 is operated when the cartridge B is mounted to or removed from the image forming apparatus main body A. <Configuration of the image forming apparatus main body>

[0542] Next, the configuration of the image forming apparatus main body A according to this embodiment will be described with reference to FIGS.

[0543] 31A and 31B are diagrams showing the configuration of the image forming apparatus main body A. (a) is an exploded perspective view of the drive side, and (b) is a view seen in a direction perpendicular to the longitudinal direction.

[0544] 32 is a diagram showing the configuration of the image forming apparatus main body A. (a) is a cross-sectional view taken along line X204-X204 in FIG. 31(b), (b) is a cross-sectional view taken along line X205-X205 in (a), and (c) is an enlarged view showing the DT20 area in (a). Note that the drawings showing the image forming apparatus main body A in this embodiment and the following embodiments are shown in more detail than in Example 1. Components corresponding to those described in Example 1 are given the same names as those in Example 1.

[0545] 31A, the image forming apparatus main body A according to this embodiment includes, from the drive side plate 15 toward the direction of arrow DW4, which is the longitudinal driving direction, a cylindrical cam 86, a drive transmission member 81, and a drive-side outer frame 50. A drive transmission member bearing 83 equipped with a drive transmission member spring 84 is attached to the drive-side outer frame 50.

[0546] The drive side plate 15 has a hole 15n through which the gear portion 81a of the drive transmission member 81 passes, and an abutment portion 15m that abuts against the pressed member 297 of the rack gear mechanism 290 described above.

[0547] The drive transmission member 81 has a second gear portion 81k for receiving a drive force from a drive source (not shown) of the image forming apparatus main body A. A cylindrical portion 81m is connected between the gear portion 81a and the second gear portion 81k. The diameter of the cylindrical portion 81m is set to be slightly larger than the tip circle of the gear portion 81a, and the cylindrical portion 81m slides in the hole 15n of the drive side plate 15.

[0548] The driving side outer frame 50 is provided with a protrusion 50a that protrudes inward in the longitudinal direction.

[0549] Here, the drive transmission member 81 is configured to be inclined in a predetermined inclination direction DW1, which will be described below.

[0550] As shown in Figure 32(a), the protrusion 50a of the drive-side outer frame 50 is positioned at a position rotated clockwise by an angle K21 from the upstream side of the vertical direction DZ in the direction of gravity DZ1, with the drive transmission member bearing 83 (see Figure 7(b)) as the center. A line connecting the protrusion 50a to the center of the drive transmission member bearing 83 (see Figure 7(b)) is defined as direction D205, and the direction from the protrusion 50a toward the center of the drive transmission member bearing 83 is defined as inclination direction DW1.

[0551] As shown in FIG. 32( b), the drive transmission member 81 has a fixed end 81c cantilevered and supported by a drive transmission member bearing 83. As described in the first embodiment, when the door 13 is open, the cylindrical cam 86 moves toward the drive side in the longitudinal direction (see FIG. 7). A rib extending toward the non-drive side in the longitudinal direction on the wall surface connecting the second gear portion 81k and the cylindrical portion 81m is referred to as the abutment rib 81k2, and the end face of the second gear portion 81k on the drive side in the longitudinal direction is referred to as the abutment surface 81k1. The drive transmission member 81 abuts against the cylindrical cam 86 at the abutment rib 81k2 and against the protrusion 50a at the abutment surface 81k1. At this time, the drive transmission member 81 tilts in the inclination direction DW1 at the coupling tip end 81b1 side, with the fixed end 81c as a fulcrum.

[0552] The drive transmission member 81 has backlash between the cylindrical cam 86 and the protrusion 50a, and the amount of tilt of the drive transmission member 81 in the tilt direction DW1 is determined by the abutment of the gear portion 81a against the hole 15n in the drive side plate 15. Here, as shown in FIG. 32(c), a line SL1 is a line parallel to the direction D205 and passing through the center of the drive transmission member bearing 83 (see FIG. 7(b)). The hole 15n in the drive side plate 15 has a pair of gear support surfaces 15n1 on the tilt direction DW1 side that are symmetrical with respect to the line SL1. The position of the drive transmission member 81 in the tilt direction DW1 is determined by the abutment of the gear portion 81a against the pair of gear support surfaces 15n1.

[0553] Furthermore, since the drive transmission member 81 is supported in a cantilever manner with the fixed end 81c as a fulcrum, the coupling tip end 81b1 also tilts in the tilt direction DW1 due to the tilt caused by gravity.

[0554] Furthermore, the gear portion 81a of the drive transmission member 81 is not restricted in position in a direction D206 perpendicular to the direction D205, and when an external force acts on the gear portion 81a, etc., it tilts in the direction D206. <Installation of the cartridge into the main body of the image forming apparatus>

[0555] Next, the operation of mounting the cartridge B in this embodiment into the image forming apparatus main body A will be described with reference to Figure 33. Figure 33 is a cross-sectional view showing the mounting operation of the cartridge B into the image forming apparatus main body A, and the cross-sectional position corresponds to the X202-X202 cross section in Figure 29(a). Also, (a) shows the state immediately before the cartridge is mounted, and (b) shows the state after the cartridge has been mounted.

[0556] As shown in Figure 33(a), when the cartridge B is in a state immediately before being mounted in the image forming apparatus main body A, the pressed surface 297a of the pressed member 297 faces the abutment portion 15m of the drive side plate 15 constituting the image forming apparatus main body A. At this time, the rack gear mechanism 290 is in a standby state. Also, the gear portion 291a of the rack gear 291 is about to mesh with the gear portion 81a of the drive transmission member 81. When the cartridge B moves in the mounting direction C from this point, it reaches the state after the cartridge B has been mounted, as shown in Figure 33(b).

[0557] At this time, the position of the rack gear 291 relative to other parts of the cartridge will be referred to as the initial position, engagement position, operating position, pre-movement position, etc. The rack gear 291 is biased to the initial position by a tension spring 292.

[0558] Here, because movement of the rack gear 291 in the direction of arrow E22 along the first movable direction D200 is restricted, interference occurs between the gear portion 81a of the drive transmission member 81 and the gear portion 291a of the rack gear 291 during the installation process of the cartridge B. However, as described above, the gear portion 81a of the drive transmission member 81 can be tilted in a direction D206 perpendicular to the direction D205 by an external force. Therefore, if the downstream component of the direction D206 in the installation direction C is defined as the escape direction DW2, when the gear portion 291a of the rack gear 291 comes into contact with the gear portion 81a of the drive transmission member 81, the gear portion 81a tilts in the escape direction DW2. This prevents interference between the gear portion 291a of the rack gear 291 and the gear portion 81a. Thereafter, the gear portion 291a of the rack gear 291 moves to a position where it meshes with the gear portion 81a of the drive transmission member 81, and the gear portion 81a of the drive transmission member 81 meshes with the gear portion 291a due to its own weight.

[0559] When the cartridge B is mounted in the image forming apparatus main body A, the pressed member 297 is pressed by the contact portion 15m of the drive side plate 15 and moved to the second position. This causes the rack gear mechanism 290 to enter an operating state. <Engagement Operation of the Drive Transmission Member 81>

[0560] Next, the operation of the drive transmission member 81 until the coupling recess 81b engages with the coupling protrusion 263b of the drive-side drum flange 263 when the drive transmission member 81 is driven will be described with reference to Figures 34 to 36. Figure 34 is a cross-sectional view showing the operation when the drive transmission member 81 is driven, and the cross-sectional position corresponds to the X202-X202 cross-section in Figure 29(a). (a) shows the drive transmission member 81 being driven in a tilted state, and (b) shows the drive transmission member 81 immediately after being aligned with the rotation axis Ax1 of the drum 62. Figure 35 is a cross-sectional view showing the engagement operation of the drive transmission member 81, taken along the X203-X203 cross-section shown in Figure 34(a). (a) shows the drive transmission member 81 in a tilted state, (b) shows the drive transmission member 81 aligned with the rotation axis Ax1 of the drum 62, and (c) shows the state in which the coupling recess 81b engages with the coupling protrusion 263b of the drive-side drum flange 263. 36 is a cross-sectional view showing the operation of the rack gear mechanism 290 after the drive transmission member 81 has been aligned with the rotation axis Ax1 of the drum 62, and the cross-sectional position corresponds to the X202-X202 cross section in FIG. 29( a). (a) shows the process leading to the movement of the rack gear 291 being restricted by the locking member 293, and (b) shows the state in which the movement is restricted.

[0561] As shown in Figure 34(a), when the drive transmission member 81 rotates in the rotational direction CW, as in Example 1, the gears mesh with each other, generating a meshing reaction force FD20 in the gear portion 81a, which is a reaction force to the meshing force FD1. At this stage, the tilted gear portion 81a moves in the direction of the meshing reaction force FD20, so not much force is transmitted to the gear portion 291a, and the meshing force FD1 is very small. Therefore, the meshing force FD1 is smaller than the force F20 due to the tension spring 292 acting on the rack gear 291, and the rack gear 291 does not move due to the meshing force FD1. The rack gear 291 remains in its initial position.

[0562] In this embodiment, the tension spring 292 is used as the elastic member for biasing the rack gear 291 to the initial position, but this is not limitative. For example, the rack gear 291 may be biased using a different type of spring.

[0563] While the rack gear 291 remains in its initial position, the gear portion 81a of the drive transmission member 81 moves due to the meshing force FD1. If the axis of the drive transmission member 81 is the rotation axis Ax3 (see FIG. 35(a)), the movement of the gear portion 81a causes the rotation axis Ax3 to move in a direction coinciding with the rotation axis Ax1 of the drum 62. Then, as shown in FIG. 34(b), the gear portion 81a abuts against the restricting portion 73j, and the rotation axis Ax3 of the drive transmission member 81 and the rotation axis Ax1 of the drum 62 become substantially coaxial.

[0564] As in the first embodiment, a thrust force FA is generated by the engagement of the helical teeth of the gear portion 81a and the gear portion 291a. As shown in FIG. 35(b), the thrust force FA is applied to the drive transmission member 81 in the axial direction (longitudinal direction), causing the drive transmission member 81 to move longitudinally toward the non-drive side (the side closer to the cartridge). That is, the drive transmission member 81 approaches and contacts the coupling protrusion 63b. When the drive transmission member 81 rotates and the triangular phases of the coupling recess 81b and the coupling protrusion 63b are aligned, the coupling protrusion 263b enters the coupling recess 81b, as shown in FIG. 36(c). As in the first embodiment, when the surfaces constituting the coupling protrusion 263b and the coupling recess 81b come into contact and drive is transmitted, a new thrust force FC is generated because both are twisted (inclined) relative to the axis.

[0565] When the gear portion 81a of the drive transmission member 81 abuts against the restricting portion 73j or when the coupling recess 81b engages with the coupling protrusion 63b, movement of the gear portion 81a is restricted in directions other than the rotational direction. When movement of the drive transmission member 81 is restricted, force can be sufficiently transmitted from the gear portion 81a to the gear portion 291a of the rack gear 291. Therefore, as shown in FIG. 34( b ), if the force received by the gear portion 291a due to the meshing force between the gears at this time is defined as meshing force FD2, meshing force FD2 is greater than the force F20 biasing the rack gear 291 by the tension spring 292. Therefore, meshing force FD2 moves the rack gear 291 from its initial position in the direction of arrow E28 along the first movable direction D200.

[0566] When the rack gear 291 moves a certain amount in the direction of arrow E28, the pressed portion 291c3 comes into contact with the pressing portion 293a of the locking member 293, as shown in FIG. 36(a). Here, the locking member 293 is biased in the direction of arrow E27 along the second movable direction D201 by a force F27 from the torsion coil spring 294. Therefore, the pressed portion 291c3 of the rack gear 291 receives a force F28a from the pressing portion 293a of the locking member 293. If the component of the force F28a in the first movable direction D200 is defined as force F28a1, force F28a1 is set to be larger than the force F20a from the tension spring 292. Therefore, the rack gear 291 moves in the direction of arrow E28, and the locking member 293 further moves in the direction of arrow E27.

[0567] When the rack gear 291 moves in the direction of arrow E28, as shown in FIG. 36( b), the gear portion 291a is disengaged from the gear portion 81a of the drive transmission member 81. In this state, the locking member 293 is biased in the direction of arrow E27 along the second movable direction D201 by a force F27a from the torsion coil spring 294. As a result, the pressed portion 291c3 of the rack gear 291 receives a force F28b from the pressing portion 293a of the locking member 293. If the component of the force F28b in the first movable direction D200 is defined as force F28b1, F28b1 is set to be greater than the force F20b from the tension spring 292. As a result, the movement of the rack gear 291 in the direction of arrow E22 is restricted by the locking member 293. Also, the locking member 293 moves from the unlocked position shown in FIG. 36(a) to the locked position shown in FIG. 36(b), and remains in that state.

[0568] As a result, the gear portion 291a is maintained in a state separated from the engagement with the gear portion 81a of the drive transmission member 81. The position of the rack gear 291 in the cartridge at this time is referred to as the retracted position, non-engagement position, post-movement position, or the like.

[0569] In this way, the rack gear 291 moves from the initial position to the retracted position by meshing with the gear portion 81a of the drive transmission member 81 and receiving a driving force from the gear portion 81a. When the rack gear 291 is in the retracted position, the movement of the rack gear 291 is locked by the locking member 293, which is in the lock position, and the rack gear 291 remains in the retracted position.

[0570] One of the initial position (see FIG. 36( a)) and the retracted position (see FIG. 36( b)) of the rack gear 291 may be referred to as the first position of the rack gear 291, and the other may be referred to as the second position of the rack gear 291. The rack gear 291 is a movable member that can move between the first position and the second position. As the rack gear 291 moves, the teeth of the rack gear 291 also move between the first position and the second position.

[0571] Similarly, one of the locked position (see FIG. 36( a)) and the unlocked position (see FIG. 36( b)) of the locking member 293 may be referred to as the first position of the locking member 293, and the other may be referred to as the second position of the locking member 293. The locking member 293 is also a movable member that can move between the first position and the second position.

[0572] The locking member 293 that keeps the rack gear 291 in the retracted position is not essential, but it is desirable to have one. To explain why, a hypothetical situation will be described in which the cartridge does not have the locking member 293 and the movement of the rack gear 291 is not restricted by the locking member 293.

[0573] In this case, the rack gear 291 moves to a retracted position by receiving a driving force from the drive transmission member 81, and when it disengages from the drive transmission member, it moves in the direction of arrow E22 due to the force F20b of the tension spring 292 and attempts to return to its initial position.

[0574] As a result, the gear portion 291a of the rack gear 291 also moves in the direction of arrow E22 and collides with the gear portion 81a of the drive transmission member 81, after which the gear portion 291a and the gear portion 81a mesh again. Furthermore, the drive transmission member 81 rotates in the rotational direction CW, and the gear portion 81a moves the gear portion 291a of the rack gear 291 again in the direction of arrow E28 toward the retracted position. After that, the rack gear 291 reaches the retracted position, and the meshing between the gear portion 291a of the rack gear 291 and the gear portion 81a of the drive transmission member 81 is released. Then, the gear portion 291a again moves in the direction of arrow E22 toward the initial position, and the gear portion 291a collides with the gear portion 81a of the drive transmission member 81.

[0575] The reciprocating motion of the rack gear 291 as described above is repeated at the gear meshing cycle, which may cause abnormal noise or reduce the rotational accuracy of the drive transmission member 81. On the other hand, in the cartridge of this embodiment which has the locking member 293, as described above, the locking member 293 maintains the rack gear 291 in a state in which the gear portion 291a is separated from the meshing of the gear portion 81a of the drive transmission member 81. This solves the above-mentioned problem. <Removing the Cartridge>

[0576] Next, the operation of removing cartridge B from the image forming apparatus main assembly A will be described with reference to Figure 37. Figure 37 is a cross-sectional view showing the operation of removing cartridge B, and the cross-sectional position corresponds to the X202-X202 cross section in Figure 29(a). (a) to (d) show the process.

[0577] 37(a), in order to remove the cartridge B, the cartridge B is moved in the direction opposite to the mounting direction C. At this time, the pressed surface 297a of the pressed member 297 separates from the abutting portion 15m of the drive side plate 15, and the pressed member 297 moves to the first position by the force F22 of the initialization spring 298.

[0578] As shown in Figure 37 (b), the first pressed surface 295d of the rotating member 295 is pressed against the cylindrical portion 297b, causing the rotating member 295 to rotate in a rotational direction Q21 around the rotation axis Ax20 (see Figure 30). At this time, the angle between the actuated arm 294a and the acting arm 294b of the torsion coil spring 294 becomes wider (less than 20°) than in the free state, and the torsion coil spring 294 attempts to return to its closing position. Because the actuated arm 294a of the torsion coil spring 294 is supported by the first cylindrical portion 295a of the rotating member 295, a restoring force F29 is generated in the acting arm 294b. As the second cylindrical portion 293d receives the force F29, the locking member 293 moves in the direction of arrow E21.

[0579] As shown in Figure 37(c) , when the locking member 293 moves in the direction of arrow E21, the pressing portion 293a disengages from the pressed portion 291c3 of the rack gear 291. That is, when the locking member 293 moves from the locked position (see Figure 37(a)) to the unlocked position (see Figure 37(c)), the locking of the rack gear 291 by the locking member 293 is released. The force F20a from the tension spring 292 moves the rack gear 291 in the direction of arrow E22 from the retracted position (see Figure 37(a)) toward the initial position (see Figure 37(d)).

[0580] Then, as shown in FIG. 37(d), the rack gear mechanism 290 enters a standby state.

[0581] After going through the above process, the cartridge B is removed from the main assembly A of the image forming apparatus.

[0582] As described above, when the pressed member 297 is pressed by the drive side plate 15, the rack gear mechanism 290 is in an operating state, and the locking member 293, which is in the locked position, locks the rack gear 291 in the standby position. On the other hand, when the pressed member 297 is not pressed by the drive side plate 15, the rack gear mechanism 290 is in a standby state. In other words, the locking member 293 moves from the locked position to the unlocked position, so that the rack gear 291 is not locked and is allowed to move to the initial position.

[0583] In other words, the pressed member 297 is an operating portion that is operated to switch between an operating state in which the locking member 293 can lock the rack gear 291 and a standby state in which the locking member 293 does not lock the rack gear 291. The locking member 293 in the operating state is maintained in the locked position, and the locking member 293 in the standby state is released from the state maintained in the locked position and is therefore positioned in the unlocked position.

[0584] As shown in Figure 29, the preferred range of angle K20, which is the angle formed by the line connecting the axis of drum 62 and the axis of developing roller 32 and the line perpendicular to first movable direction D200, is set by the configuration of image forming apparatus main body A. This will be explained using Figure 38.

[0585] Figure 38 is a cross-sectional view of the image forming apparatus main body A illustrating the preferred range of angle K20, and corresponds to the X202-X202 cross section in Figure 29(a). The shapes of the components are simplified for clarity, as are the shapes of the components that are not necessary for the explanation. Similarly to Figure 29(b), the rack gear 291 illustrated in Figure 38 is illustrated not only in the position shown in this embodiment, but also in positions where angle K20 is in both the positive and negative directions, for the sake of explanation.

[0586] If the positive range of angle K20 is angle K22 and the negative range is angle K23, the preferred range of angle K22 is determined by the shape of the drive side plate 15, and the preferred range of angle K23 is determined by the inclination direction DW1 of the drive transmission member 81.

[0587] First, angle K22 will be described. Angle K22 is the limit angle at which the rack gear 291 does not interfere when it moves in the direction of arrow E28 along the first movable direction D200. In the image forming apparatus main body A of this embodiment, the space SP1 downstream of the drive transmission member 81 in the cartridge mounting direction C is narrow. This is because components constituting the image forming apparatus main body A are arranged in an area that does not interfere with the mounting trajectory of the cartridge B. In the image forming apparatus main body A of this embodiment, the drive source (motor) and the gear train connected thereto are arranged in space SP2. When the rack gear 291 moves, angle K22 is the angle at which it can intrude into space SP1, and angle K22 is preferably 50° or less.

[0588] Next, the angle K23 will be described. In Fig. 38, each position is defined as follows.

[0589] The position PO1 is the center position of the coupling recess 81b (see FIG. 13, etc.) of the drive transmission member 81 inclined in the inclination direction DW1.

[0590] The position PO2 is the center position of the coupling protrusion 263b of the drum 62 (see FIG. 24).

[0591] A position PO3 indicates the center position of the coupling recess 81b after the drive transmission member 81 has been moved by the meshing reaction force FD20 (see FIG. 34(a)).

[0592] At this time, the distance L22 between positions PO2 and PO3 measured in a direction perpendicular to the axis Ax1 of the drum 62 corresponds to the amount of misalignment between the coupling convex portion 63b and the coupling concave portion 81b described in the section on coupling engagement conditions in Example 1. In other words, angle K23 is the limit angle at which distance L22 becomes the amount of misalignment that allows engagement between the coupling convex portion 63b and the coupling concave portion 81b, and is preferably -75° or greater. It is assumed that the pressure angle of the gear portion 81a of the drive transmission member 81 is 20°, and that the drive transmission member 81 moves in the same direction as the meshing reaction force FD20.

[0593] As described above, the preferred range of angle K20 is set depending on the configuration of image forming apparatus main body A. Therefore, depending on the image forming apparatus main body to which this embodiment is applied, the preferred range of angle K20 is set appropriately in accordance with the above-mentioned conditions.

[0594] As described above, in this embodiment, as in the previously described first embodiment, as shown in Figure 35, the force FA generated by the meshing of the rack gear 291 with the gear portion 81a of the drive transmission member 81 can be used to move the drive transmission member 81 toward the cartridge B. The force FA generated by the meshing can be used to connect the drive transmission member 81 to the cartridge B.

[0595] By employing such a rack gear 291 in the cartridge B, it is possible to simplify the mechanism inside the main assembly A of the apparatus required to move the drive transmission member 81 toward the cartridge B, as in the first embodiment. For example, it becomes possible to eliminate a spring or the like inside the main assembly A of the apparatus that biases the drive transmission member 81 toward the cartridge B, or to reduce the force of such a spring or the like.

[0596] In particular, in this embodiment, after the drive transmission member 81 approaches cartridge B and is connected to cartridge B, the engagement between the drive transmission member 81 and the rack gear 291 is released (see FIG. 36(b)). This is because the rack gear 291 can move to a position where it does not mesh with the drive transmission member 81. Therefore, even when the user removes cartridge B from the apparatus main body A, the drive transmission member 81 and the rack gear 291 are not meshed. As a result, the user can remove cartridge B with a light force. This is because there is little possibility that the drive transmission member 81 and the rack gear 291 will get caught and interfere with the removal of cartridge B. <Modification 1 of Embodiment 2>

[0597] In this embodiment, the rack gear mechanism transitions from the standby state to the operating state when the cartridge B is mounted in the image forming apparatus main body A, but it may also transition when the user closes the opening / closing door 13 (see FIG. 8). Below, we will show a first modification of the second embodiment, which is a partial modification of the second embodiment. For ease of explanation, the above-described configuration may be referred to as a representative example of the second embodiment, and the configuration shown below may be referred to as the first modification of the second embodiment.

[0598] 39A and 39B are diagrams showing the operation of the rack gear mechanism 2900 in this modified example, with (a) showing the rack gear mechanism 2900 in a standby state and (b) showing the rack gear mechanism 2900 in an operating state.

[0599] 39A, when the rack gear mechanism 2900 is in the standby state, a pressed surface 2970a of the pressed member 2970 protrudes a predetermined amount from the cleaning frame 71. The protruding direction of the pressed member 2970 is defined as a fourth movable direction D204. The link member 2990 is rotatably supported such that the first support shaft 2990a is rotatably supported in a support hole 2970f of the pressed member 2970, and the second support shaft 2990b is rotatably supported in a support hole 2950g of the rotating member 2950.

[0600] The pressed surface 2970a of the pressed member 2970 is pressed in the direction of arrow E200 along the fourth movable direction D204 by the cartridge pressing member 1 provided on the opening / closing door 13. This movement is transmitted to the rotating member 2950 via the link member 2990, causing the rotating member 2950 to rotate in the rotation direction Q20 about the rotation axis Ax20. Due to the rotation of the rotating member 2950, ​​the rack gear mechanism 2900 operates in the same manner as in this embodiment, and is brought into the operating state shown in FIG.

[0601] When the rack gear mechanism 2900 is in an operating state, if the door 13 is opened and the cartridge pressing member 1 is moved away from the pressed surface 2970a, a spring (not shown) moves the pressed member 2970 in the direction of arrow E201 along the fourth movable direction D204. When the pressed member 2970 is moved in the direction of arrow E201, the rotating member 2950 is rotated in the rotation direction Q21 about the rotation axis Ax3 via the link member 2990. Due to the rotation of the rotating member 2950, ​​the rack gear mechanism 2900 enters a standby state as shown in FIG. 39( a) by the same action as in this embodiment.

[0602] The pressed member 2970 is an operating unit that is operated to switch between a standby state and an operating state of the rack gear mechanism 2900. The rack gear mechanism 2900 has the locking member 293 and the rack gear 291 described in the above-mentioned second embodiment. Operating the pressed member 2970 switches between a state in which the locking member 293 can lock the rack gear 291 and a state in which the locking member 293 does not lock the rack gear 291 and allows the rack gear 291 to move.

[0603] In order to realize the above operation, the movable range of the link member 2990 and the movable direction of the pressed member 2970 are appropriately restricted.

[0604] In this modification, the pressed member 2970 is moved by the cartridge pressing member 1 provided on the opening / closing door 13, but it may be configured so that it is directly operated by the user. In this case, the user operates the pressed member 2970 after installing the cartridge B in the image forming apparatus main body A. <Modification 2 of Example 2>

[0605] Furthermore, instead of the rack gear 291 having the gear portion 291a described in the second embodiment, an elastic member (elastic body) without teeth may be provided on the drive side of the cartridge. Such a configuration will be described as a second modified example of the second embodiment.

[0606] 40A and 40B are diagrams illustrating this modified example, in which (a) is a perspective view of the cartridge B of this modified example, and (b) is a cross-sectional view showing engagement with the drive transmission member 81.

[0607] As shown in FIG. 40(a), an elastic moving member 2912a is provided on a slide member 2912 (corresponding to the rack gear 291) of a slide mechanism 2902 (corresponding to the rack gear mechanism 290).

[0608] The elastic moving member 2912 a is capable of moving linearly in the same manner as the rack gear 291 .

[0609] The elastic moving member 2912a is made of an elastically deformable material such as polyurethane foam, rubber, elastomer, etc. In this modification, polyurethane foams such as ESH manufactured by Inoac Corporation and Moltoprene manufactured by Inoac Corporation are used. If the surface of the elastic moving member 2912a is designated as surface 2912a1, the distance from the rotation axis Ax1 of the drum 62 to surface 2912a1 is set to 12.74 mm in orthogonal direction D2072 orthogonal to the first movable direction D2002.

[0610] This distance corresponds to the shortest distance measured from the axis Ax1 to the surface 2912a1 along a direction perpendicular to the axis Ax1. This distance also corresponds to the distance measured from the axis Ax1 to a tangent to the surface 2912a1 along a direction perpendicular to the axis Ax1. This distance is preferably 75-120% of the drum radius.

[0611] The elastic moving member 2912a is an elastic body, and can be compressed and deformed by contacting the gear portion 81a of the drive transmission member 81. Therefore, the allowable range of the distance from the axis Ax1 of the drum 62 to the surface 2912a1 of the elastic moving member 2912a is wider than the distances L21 and L22 (see FIG. 29B) in the second embodiment. Note that the distances L21 and L22 are the distances from the axis Ax1 of the drum 62 to the gear portion 291a of the rack gear 291, and for details, please refer to the above description.

[0612] In other respects, the preferred arrangement and preferred movement direction of the elastic moving member 2912a are similar to those of the rack gear 291 described as the main component of the second embodiment.

[0613] However, when the elastic moving member 2912a, which is an elastic body, meshes with the gear portion 81a of the drive transmission member 81, it exerts a strong force to hold the drive transmission member 81. Therefore, the preferable ranges of the angles K20 and K21 described above with reference to Figure 29 can be wider than those described above.

[0614] That is, in this modified example, the preferable range of angle K20 is not less than -70 degrees and not more than 100 degrees. Similarly, in this modified example, the preferable range of angle K21 is not less than -70 degrees and not more than 100 degrees.

[0615] For the elastic moving member 2912a, the above-mentioned explanations regarding the suitable range of the angle K20 and the suitable range of the angle K21 for the rack gear 291 can be applied to the more suitable range of the angle K20 and the more suitable range of the angle K21.

[0616] As described above with reference to Figure 29, when viewing the cartridge along the axis Ax1 of the photosensitive drum, the reference line is a line extending from the axis Ax1 of the photosensitive drum 62 to pass through the axis Ax2 of the developing roller 32. In this modified example, the movable direction of the elastic moving member 2912a corresponds to the movable direction D200 shown in Figure 29. Similarly, the direction perpendicular to the movable direction of the elastic moving member 2912 corresponds to the perpendicular direction D207 shown in Figure 29. The angle that the perpendicular direction D207 makes with respect to the reference line is K20.

[0617] In this modified example, the perpendicular direction D207 is also the direction of the normal to the elastic moving member 2912a that extends from the elastic moving member 2912a so as to move away from the axis Ax1 of the drum 62.

[0618] Furthermore, the angle that a line extending from the axis Ax1 of the drum 62 toward the surface of the elastic moving member 2912a makes with the reference line is K21. As with the gear portion 291a of the rack gear 291 described in FIG. 29(a), it is preferable that at least a portion of the surface 2912a1 of the elastic moving member 2912a is located outside the coupling portion 263b. In other words, when measured along the direction of the axis Ax1 of the drum 62 (see FIG. 29(a)), at least a portion of the surface 2912a1 of the elastic moving member 2912a is located farther from the non-drive side end of the drum 62 than the coupling portion 263a.

[0619] Furthermore, it is preferable that the surface 2912a1 of the elastic moving member 2912a is at least partially exposed to the outside so as to face the axis Ax1 of the drum 62 (see FIG. 40(a)). This is because the surface 2912a1 of the elastic moving member 2912a needs to come into contact with the drive transmission member 81 that is disposed between the surface 2912a1 and the axis Ax1, as shown in FIG. 40(b).

[0620] 40(b), the elastic moving member 2912a enters the space between adjacent gear teeth of the gear portion 81a of the drive transmission member 81 and deforms to fit the shape of the gear teeth. The deformed elastic moving member 2912a acts in the same way as the rack gear 291, moving the drive transmission member 81 and moving the slide member 2912 in the direction of arrow E202 along the movable direction D2002. This causes the slide member 2912 to operate in the same way as the rack gear 291.

[0621] As the slide member 2912 moves, the elastic moving member 2912a moves linearly or in a plane in a direction along its own surface 2912a1.

[0622] Even with such a configuration of the elastic moving member 2912a, it is possible to engage the cartridge with the gear portion 81a of the drive transmission member 81. In this modified example, the gear portion 81a bites into the elastic moving member 2912a, which has the advantage of making it easier to stabilize the meshing state between the elastic moving member 2912a and the gear portion 81a.

[0623] The meshing operation between the elastic moving member 2912a and the gear portion 81a is the same as the meshing operation between the elastic member and the gear portion 81a shown in Example 4. Details will be explained later in Example 4.

[0624] Next, Example 3 will be described below with reference to Figures 41 to 51. In particular, among the elements disclosed in this Example, those corresponding to the members described in Example 2 will be given the same names as the members in Example 2, and only the differences from Example 2 will be described.

[0625] First, the cartridge configuration of this embodiment will be described with reference to Figure 41. Figure 41 is a perspective view of cartridge B. Cartridge B in this embodiment is configured with a cleaning unit 260 and a developing unit 320, similar to embodiment 2. The developing unit 320 has a drive-side developer side member 326. The drive-side developer side member 326 is located on the drive side of the cartridge and is part of the frame that configures the developing unit 320. The drive-side developer side member 326 is also provided with a friction force imparting portion (friction material) 326a. In this embodiment, the friction force imparting portion 326a is fixed to the drive-side developer side member 326.

[0626] The direction along the rotation axis Ax1 of the drum 62 is the longitudinal direction D302, the side of the driving side drum flange 263 is the driving side, and the opposite side from the driving side is the non-driving side. The direction from the non-driving side to the driving side is the direction of arrow E32, and the direction from the driving side to the non-driving side is the direction of arrow E33.

[0627] Next, the range of the frictional force applying portion 326a will be described with reference to Figure 42. As will be described in detail later, the frictional force applying portion 326a is a member configured to come into contact with the gear portion 81a of the drive transmission member 81. Therefore, the preferred location of the frictional force applying portion 326a conforms to the preferred location of the gear portion 30a (see Figure 9) of the developing roller gear 30 in Example 1 configured to mesh with the gear portion 81a, and the gear portion 291a of the rack gear 291 in Example 2.

[0628] For example, the preferred arrangement of frictional force applying portion 326a in the axial direction of photosensitive drum 62 is equivalent to the preferred ranges of gear portion 30a and gear portion 291a. The surface of frictional force applying portion 326a is at least partially exposed toward axis Ax1 of drum 62.

[0629] On the other hand, there is a suitable arrangement specific to the frictional force applying portion 326a of this embodiment, which will be described in particular detail below.

[0630] Figure 42 shows the arrangement of the frictional force applying portion 326a. (a) is a view taken along a direction perpendicular to the rotation axis of the drum 62, and (b) is a cross-sectional view taken along the line X300-X300 in (a). Note that (b) of Figure 42 only shows the drum 62, the developing roller 32, and the frictional force applying portion 326a. Furthermore, (b) of Figure 42 also shows the frictional force applying portion 326a in the arrangement of this embodiment, as well as in a state where it is arranged in the positive and negative directions of angle K30, which will be described later for the sake of explanation. The positive angle is angle K30U, and the negative angle is angle K30L.

[0631] As shown in Figure 42(a), in the longitudinal direction D302, at least a portion of the frictional force applying portion 326a is located in the direction of arrow E32 (longitudinal outer side, on the side away from the cartridge B) than the tip 263b1 of the drive-side drum flange 263. Furthermore, at least a portion of the frictional force applying portion 326a is disposed within a range of 4 to 9 mm from the tip 263b1 toward the drive side. Note that this range may be set even larger depending on the configuration of the drive-side drum flange 263 and the configuration of the image forming apparatus main body A to which it is applied.

[0632] 42(b), a direction perpendicular to the longitudinal direction D302 and parallel to the frictional force applying portion 326a is defined as direction D300. In direction D301 perpendicular to direction D300, a distance L30 is defined as a distance from the axis of the drum 62 to the frictional force applying portion 326a. In this case, if the frictional force applying portion 326a is a rigid body, the distance L30 is set to be in the range of 90% to 120% of the radius of the drum 62, and particularly preferably 92% to 120%.

[0633] In this embodiment, the radius of the drum 62 is 12 mm. The distance L30 from the axis of the drum 62 to the frictional force applying portion 326a is set to 10.8 mm or more, which is 90% of the radius of the drum 62, and more preferably 11.041 mm or more, which is 92%. Furthermore, L30 is set to 14.439 mm or less, which is 120% of the radius of the drum 62. In this embodiment, the distance L30 is set to 106.2% (12.74 mm) of the radius of the drum 62.

[0634] Furthermore, when the frictional force applying portion 326a is an elastic body (elastic member), the distance L30 is set to be in the range of 75% to 120% of the radius of the drum 62 when no load is applied to the frictional force applying portion 326a. This is because, when the cartridge B is mounted in the image forming apparatus main body A and the frictional force applying portion 326a is deformed, the distance L30 is set to be in the range of 90% to 120%, and particularly preferably 92% to 120%.

[0635] In addition, if the frictional force imparting portion 326a is not a flat surface, the direction of at least a portion of the tangent (tangential plane) is set to direction D300.In this case, the frictional force imparting portion 326a may have an arc shape that is convex or concave toward the rotational axis Ax1 of the drum 62, or may be a surface that includes concaves and convexes.

[0636] A straight line extending from the axis of the drum 62 to pass through the axis of the developing roller 32 is used as a reference. The angle between this reference line and a direction D301 perpendicular to the frictional force imparting portion 326a is defined as angle K30. Note that direction D301 is the direction of a straight line passing through the frictional force imparting portion 236a and extending in a direction away from the axis of the drum 62. In other words, D301 is the direction of a normal to the frictional force imparting portion 326a extending in a direction away from the drum 62.

[0637] The positive direction of angle K30 is the downstream direction of the rotation of drum 62. That is, the positive side of angle K30 is the downstream side of the direction of arrow R, which is the rotation direction of drum 62, and the negative side of angle K30 is the upstream side of the direction of arrow R. Angle K30 is preferably between −70° and 100°.

[0638] More specifically, the preferable range of the angle K30 varies depending on the material used for the frictional force applying portion 326a. The preferable range of the angle K30 (deg) corresponding to the material used for the frictional force applying portion 326a is shown below.

[0639] When a wrapping film is used as the frictional force applying portion 326a, the angle K30 is preferably in the range of 0 degrees to 100 degrees.

[0640] When double-sided tape is used as the frictional force applying portion 326a, the preferable range of the angle K30 is not less than −50 degrees and not more than 100 degrees.

[0641] When polyurethane foam is used as the frictional force applying portion 326a, the preferable range of the angle K30 is not less than −70 degrees and not more than 100 degrees.

[0642] The preferred range of the angle K30 in the silicon sheet is -50 degrees or more and 100 degrees or less.

[0643] The wrapping film used was LWFS-30-600 (grain size #600) available from Sankyo Rikagaku Co., Ltd.

[0644] The double-sided tape used was No. 5000N(C) available from Nitto Denko Corporation.

[0645] The polyurethane foam used was ESH, available from Inoac Corporation.

[0646] The angle K30 is set according to FIG. 51, and the frictional force applying portion 326a is disposed.

[0647] In this example, lapping film (a plastic film for polishing) was used as a rigid material with a high coefficient of friction. In other words, the lapping film is an abrasive material. The angle K30 was set to 0°.

[0648] Furthermore, in order to allow the frictional force imparting portion 326a to act more stably on the drive transmission member 81 and to make it easier to secure space for placing the frictional force imparting portion 326a within the device main body, it is even more preferable to further narrow the range of the above-mentioned angle K30.

[0649] For a more preferable range of K30, the explanation of the preferable range of angle K20 explained with reference to FIG. 29 can be applied.

[0650] In this embodiment, angle K30 is also the angle formed by a line extending from the axis Ax1 of the drum 62 through the frictional force applying portion 326a with respect to the reference line. It is desirable that at least a portion of the frictional force applying portion 326a be located within a suitable range of angle K30.

[0651] The preferable ranges of the angle K30 and the distance L30 are determined depending on the relationship with the image forming apparatus main body A to which this embodiment is applied, and details of this will be described later.

[0652] 42, the frictional force applying portion 326a is provided on the drive-side developing side member 326, which is part of the developing unit 320. However, depending on the settings of the angle K30 and the distance L30, the frictional force applying portion 326a may be provided on part of the cleaning unit 260 (see FIG. 41). <Drive Transmission Structure of the Image Forming Apparatus Main Body>

[0653] Next, the drive transmission configuration to the drive transmission member 81 of the image forming apparatus main body A in this embodiment will be described with reference to Figure 43. Figure 43 shows the drive train of the image forming apparatus main body A, where (a) is a side view seen from the drive side and (b) is a perspective view seen from the drive side.

[0654] 43(a), a driving force is transmitted to the drive transmission member 81 from a motor gear 51 connected to a motor (not shown) which is a drive source of the image forming apparatus main body A, via a first idler gear 52 and a second idler gear 53. Also, a second gear portion 81k of the drive transmission member 81 is meshed with a gear portion 53a of the second idler gear 53. The motor gear 51 rotates in a rotational direction Q30, the first idler gear 52 in a rotational direction Q31, and the second idler gear 53 in a rotational direction Q32, and the drive transmission member 81 rotates in a rotational direction CW.

[0655] As shown in Figure 43 (b), the second gear portion 81k of the drive transmission member 81 has right-hand helical teeth, and the gear portion 53a of the second idler gear 53 has left-hand helical teeth, so that a thrust force F30 is generated by meshing according to the torque of the drive transmission member 81.

[0656] Here, the second idler gear 53 is fixed in the longitudinal direction. In addition, since the drive transmission member 81 is supported so as to be movable in the longitudinal direction, the thrust force F30 moves the drive transmission member 81 toward the inside of the image forming apparatus main body A (in the direction of the arrow DW3 toward the cartridge) due to the torsional relationship described above. The thrust force F30 is in the same direction as the axial (longitudinal) force FA generated in the gear portion 81a of the drive transmission member 81, as described in Examples 1 and 2 (see Figures 13 and 35). <Installation of the Cartridge into the Image Forming Apparatus Main Body>

[0657] Next, the operation of mounting the cartridge B in this embodiment into the image forming apparatus main body A will be described with reference to Figure 44. Figure 44 is a cross-sectional view showing the mounting operation of the cartridge B into the image forming apparatus main body A, and the cross-sectional position corresponds to the X302-X302 cross section in Figure 42(a). Also, (a) shows the state before the cartridge is mounted, and (b) shows the state after the cartridge is mounted.

[0658] As shown in FIG. 44A, before the cartridge B is mounted in the image-forming apparatus main assembly A, the frictional force applying portion 326a abuts against the gear portion 81a of the drive transmission member 81. When the cartridge B is then moved in the mounting direction C, the gear portion 81a of the drive transmission member 81 interferes with the frictional force applying portion 326a. However, as described in the second embodiment, the gear portion 81a of the drive transmission member 81 can tilt in the direction D206 perpendicular to the tilt direction DW1. Therefore, if the gear portion 81a interferes with the frictional force applying portion 326a during the mounting of the cartridge B, it can escape in the direction D206. This allows the cartridge B to be mounted without the frictional force applying portion 326a interfering with the gear portion 81a. The state after the cartridge B is mounted is as shown in FIG. 44B.

[0659] At this time, the gear portion 81a of the drive transmission member 81 comes into contact with the frictional force applying portion 326a and the hole portion 15n of the drive side plate 15 due to its own weight, and the position is determined (see FIG. 32). <Engagement Operation of the Drive Transmission Member>

[0660] Next, the operation of the drive transmission member 81 until it is driven by the motor gear 51 and the coupling recess 81b engages with the coupling protrusion 263b of the drive-side drum flange 263 will be described with reference to Figures 45 to 47. Figure 45 is a cross-sectional view showing the operation when the drive transmission member 81 is driven, and the cross-sectional position corresponds to the X302-X302 cross section in Figure 42(a). (a) shows the drive state in which the drive transmission member 81 is tilted, and (b) shows the state in which the drive transmission member 81 has moved to a position where it can engage with the drive-side drum flange 263. Figure 46 is a cross-sectional perspective view showing the engagement operation of the drive transmission member 81, and is a cross-sectional view taken along X301-X301 shown in Figure 45(b). (a) shows the state in which the drive transmission member 81 is aligned with the rotation axis Ax1 of the drum 62, and (b) shows the state in which the coupling recess 81b engages with the coupling protrusion 263b of the drive-side drum flange 263. Figure 47 is a diagram showing a state in which the frictional force applying portion 326a is elastically deformed. (a) is a cross-sectional view corresponding to the position of the X302-X302 cross section in Figure 42(a), and (b) is a cross-sectional view taken along the X303-X303 line in (a). For the sake of explanation, the tip of each tooth of the gear portion 81a of the drive transmission member 81 is referred to as the tooth tip 81a1, and the surface of each tooth downstream in the rotational direction CW is referred to as the tooth surface 81a2 (see Figure 45).

[0661] Hereinafter, two cases will be described: one in which the frictional force applying portion 326a is deformed by contact with the gear portion 81a of the drive transmission member 81, and one in which it is not deformed.

[0662] First, a case will be described in which the frictional force applying portion 326a is hard and does not elastically deform even when it comes into contact with the gear portion 81a. This corresponds to the case in which a wrapping film, among the above-mentioned examples, is used as the frictional force applying portion 326a.

[0663] Note that even if the frictional force applying portion 326a is elastically deformed, the case where the degree of deformation is so small that it can be ignored is also included in the case where the frictional force applying portion 326a is not elastically deformed.

[0664] As shown in FIG. 45( a), when the drive transmission member 81 rotates in the rotational direction CW, the tooth tips 81a1 of the gear portion 81a rub against the frictional force imparting portion 326a, resulting in a frictional force F31. As described in the second embodiment, the gear portion 81a of the tilted drive transmission member 81 is not restricted in position in the direction opposite to the tilt direction DW1 or in the direction D206 perpendicular to the direction D205, and is therefore free to move in the direction indicated by arrow E30 along the direction D300 parallel to the frictional force imparting portion 326a. Therefore, the gear portion 81a moves in the direction indicated by arrow E30 due to the frictional force F31. As the gear portion 81a moves, the rotational axis Ax3 approaches the rotational axis Ax1 of the drum 62. Then, the gear portion 81a abuts against the restricting portion 73j, and as shown in FIG. 45( b), the drive transmission member 81 becomes substantially coaxial with the drive-side drum flange 263, thereby reaching an engageable position. Furthermore, the coupling recess 81b and the coupling protrusion 263b maintain an engageable position in the direction perpendicular to the longitudinal direction.

[0665] 46(a), the frictional force F31 described above generates torque T30 on the gear portion 81a of the drive transmission member 81. Due to torque T30, a thrust force F30 is generated on the second gear portion 81k of the drive transmission member 81 as a result of meshing with the gear portion 53a of the second idler gear 53 (see FIG. 43(b)).

[0666] The thrust force F30 causes the drive transmission member 81 to move in the direction of arrow DW3, which is the non-drive side (the side closer to the cartridge) in the longitudinal direction D302, and it approaches and contacts the coupling protrusion 263b. Then, when the drive transmission member 81 rotates and the triangular phases of the coupling recess 81b and the coupling protrusion 263b are aligned, the coupling protrusion 263b enters and engages with the coupling recess 81b, as shown in Figure 46(b). Then, as in Example 1, when the surfaces constituting the coupling protrusion 263b and the coupling recess 81b come into contact and drive is transmitted, a new thrust force FC is generated because both are twisted (inclined) relative to the axis.

[0667] Next, a case where the frictional force applying portion 326a is elastically deformed by the gear portion 81a will be described. This corresponds to the case where, among the above-mentioned materials, double-sided tape, polyurethane foam, or silicone sheet is used as the frictional force applying portion 326a.

[0668] As shown in FIG. 47A , when the frictional force imparting portion 326a is elastic and has a soft surface, the tooth tips 81a1 of the gear portion 81a intrude into the frictional force imparting portion 326a. In other words, the frictional force imparting portion 326a intrudes into the space S30 between adjacent gear teeth of the gear portion 81a. When the drive transmission member 81 rotates in the rotational direction CW in this state, the tooth surface 81a2 receives a component force F33 of the reaction force from the frictional force imparting portion 326a in the rotational direction CW. In addition, the frictional force F31 from the frictional force imparting portion 326a also acts on the tooth tips 81a1 of the gear portion 81a. Therefore, the force that moves the gear portion 81a is a resultant force F34 of the frictional force F31 and the component force F33. Therefore, compared to when the frictional force imparting portion 326a is not elastically deformed by the gear portion 81a, it is possible to move the gear portion 81a with a greater force.

[0669] As shown in FIG. 47( b), the helical gear portion 81a (shown hatched in the figure) receives a component force F33 from the frictional force applying portion 326a at its tooth surface 81a2, generating a thrust force F35 in the direction of arrow DW3. The resultant force F34 (see FIG. 47( a)) of the frictional force F31 and the component force F33 generates a torque T31 in the drive transmission member 81 that is greater than that generated by the frictional force F31 alone, generating a thrust force F36 in the direction of arrow DW3 in the second gear portion 81k. The thrust force F35 generated in the gear portion 81a and the thrust force F36 generated in the second gear portion 81k move the drive transmission member 81 in the direction of arrow DW3. Therefore, the use of a helical gear allows the drive transmission member 81 to move in the longitudinal direction D302 with a greater force than when the frictional force applying portion 326a is not elastically deformed by the gear portion 81a.

[0670] After the coupling recess 81b and the coupling protrusion 263b are engaged, the gear portion 81a and the frictional force applying portion 326a may be in contact with each other or may be spaced apart. However, the power consumed by the drive source (motor) increases by the torque T30 generated from the frictional force F31 between the gear portion 81a and the frictional force applying portion 326a (or the torque T31 generated from the resultant force F34). Therefore, it is preferable that the gear portion 81a and the frictional force applying portion 326a are spaced apart.

[0671] The engagement operation of the drive transmission member 81 described above can be easily achieved by positioning the frictional force applying portion 326a within a suitable range. The suitable range was described above, but will now be explained in more detail. This will be explained using Figures 48 to 50.

[0672] First, the direction parallel to the surface of the frictional force applying portion 326a is defined as direction D300. In other words, D300 is a direction along a tangent to the surface of the frictional force applying portion 326a. The direction perpendicular to this tangent direction D300 is direction D301. In other words, D301 is a normal direction to the frictional force applying portion 326a.

[0673] A preferred range of the distance L30 from the axis of the drum 62 to the surface of the frictional force applying portion 326a in the orthogonal direction D301 will be described with reference to FIG.

[0674] Note that L30 corresponds to the distance from the axis Ax1 of the drum 62 to the tangent to the frictional force applying portion 326a, measured along a direction perpendicular to the axis Ax1 of the drum 62. L30 also corresponds to the shortest distance from the axis Ax1 of the drum 62 to the frictional force applying portion 326a, measured along a direction perpendicular to the axis Ax1 of the drum 62.

[0675] 48 is a diagram showing the relationship between the distance L30 from the axis of the drum 62 to the frictional force applying portion 326a and the gear portion 81a of the drive transmission member 81. (a), (b), and (c) are diagrams showing the relationship between the distance L30 and the position of the frictional force applying portion 326a, respectively. (a) shows the case where the distance L30 is the applicable value of this embodiment, (b) shows the case where the distance L30 is set within the preferred range in the lower limit direction, and (c) shows the case where the distance L30 is set outside the preferred range in the lower limit direction.

[0676] First, a description will be given of the case where the distance L30 is 106.2% (12.74 mm) of the radius of the drum 62, which is the applicable value in this embodiment. As shown in Figure 48(a), the center positions of the coupling recess 81b and the coupling protrusion 263b in direction D301 perpendicular to direction D300 are aligned.

[0677] Next, a case where the distance L30 is set toward the lower limit within the preferred range (the side where the frictional force applying portion 326a approaches the rotational axis Ax of the drum 62) will be described. As shown in FIG. 48B , when the distance L30 is set toward the lower limit, the distance between the frictional force applying portion 326a and the rotational axis center Ax1 of the drum 62 becomes shorter. Therefore, the distance between the coupling protrusion 263b fixed to the drum 62 and the frictional force applying portion 326a becomes shorter. When the frictional force applying portion 326a abuts against the gear portion 81a in this state, misalignment occurs between the coupling recess 81b and the coupling protrusion 263b. This misalignment amount is designated as A30. As described in Example 1, the misalignment amount A30 must be set to 1.699 mm or less as a coupling engagement condition when applied to the image forming apparatus main body A of this embodiment. When the drum radius in this embodiment is 12 mm, and the distance L30 is 92% (11.041 mm) of the radius of the drum 62, which is the lower limit, the amount of misalignment A30 is 1.699 mm.

[0678] Next, a case where the distance L30 is set outside the preferred range toward the lower limit side will be described. As shown in Figure 48(c), the distance between the frictional force applying portion 326a and the center of the drum 62 becomes even closer, and the distance between the coupling protrusion 263b and the frictional force applying portion 326a becomes even closer. When the frictional force applying portion 326a abuts against the gear portion 81a in this state, the misalignment amount A30 becomes 1.699 mm or more, and the coupling recess 81b and the coupling protrusion 263b cannot engage with each other.

[0679] As explained above, the distance L30 must be set to 92% (11.041 mm) or more of the radius of the drum 62, which is the lower limit of the preferred range of the distance L30.

[0680] The same applies to the upper limit of the preferred range of the distance L, so a description thereof will be omitted.

[0681] Next, using a line extending from the axis of the drum 62 and passing through the axis of the developing roller 32 as a reference line, a preferred upper limit range of the angle K30 that the direction D301 makes with respect to this reference line will be described with reference to Figure 50. The direction of the line that passes through the frictional force imparting portion 326a and extends perpendicular to the surface of the frictional force imparting portion 326a so as to move away from the drum axis Ax1 corresponds to the direction D301.

[0682] 50 is a diagram illustrating the upper limit of angle K30. Angle K31 is the angle formed by a reference line that extends from the rotational axis Ax1 of the drum 62 and passes through the rotational axis Ax2 of the developing roller 32, and the inclination direction DW1. Figure 50(a) shows the case where angle K30 is equal to or smaller than angle K31, and Figure 50(b) shows the case where angle K30 is equal to or larger than angle K31.

[0683] Here, the center position of gear portion 81a of drive transmission member 81 inclined to DW1 is defined as position PO31, the position after frictional force applying portion 326a abuts against gear portion 81a is defined as position PO32, and the center position of drum 62 is defined as position PO33. Furthermore, the distance between position PO32 where frictional force applying portion 326a abuts against gear portion 81a and moves and position PO33 on rotation axis Ax1 of drum 62 is defined as distance L31.

[0684] 50(a) shows the case where angle K30 is equal to or smaller than angle K31. PO32 is the position to which the frictional force applying portion 326a abuts and moves to gear portion 81a. The direction in which gear portion 81a is moved by frictional force applying portion 326a is the direction of arrow E30. Position PO32 is upstream of position PO33 on the rotational axis Ax1 of the drum 62 in the direction of arrow E30. At this time, when gear portion 81a is moved in the direction of arrow E30 by frictional force applying portion 326a, it approaches the rotational axis Ax1 of the drum 62.

[0685] On the other hand, Figure 50(b) shows the case where angle K30 is equal to or greater than angle K31. Position PO32 is the position where the frictional force applying portion 326a contacts and moves to gear portion 81a. The direction in which gear portion 81a is moved by frictional force applying portion 326a is the direction of arrow E30. Position PO32 is downstream of position PO33 on the rotational axis Ax1 of the drum 62 in the direction of arrow E30. At this time, when gear portion 81a is moved in the direction of arrow E30 by frictional force applying portion 326a, it moves away from the rotational axis Ax1 of the drum 62. For the coupling to engage in this state, distance L31 must be reduced. Distance L31 increases as angle K30 increases. Angle K30 at which the coupling can be engaged is the upper limit of the preferred range.

[0686] Next, a preferred range of the lower limit of the angle K30 formed by the direction D301, with respect to a line connecting the axis of the drum 62 and the axis of the developing roller 32, will be described with reference to FIG. 49 . In FIG. 49 , a line extending from the rotational axis Ax1 of the drum 62 so as to pass through the rotational axis Ax2 of the developing roller 32 is shown as the reference line. The angle K30 (see FIG. 42( b )) is the angle formed by the direction D301, which is perpendicular to the direction D300 parallel to the frictional force imparting portion 326a, with respect to this reference line. D301 is indicated by an arrow indicating the normal to the frictional force imparting portion 326a. More specifically, the arrow indicating the direction D301 is the normal to the frictional force imparting portion 326a, extending away from the axis Ax of the drum 62.

[0687] FIG. 49 is a diagram illustrating the lower limit of the angle K30, where (a) shows the case where the angle K30 is within the preferred range, and (b) shows the case where the angle K30 is outside the preferred range.

[0688] As shown in FIG. 49A , at the contact point between the gear portion 81a and the frictional force applying portion 326a, a force FG1 is generated in the direction of arrow E31 along direction D300, including a component in the direction of gravity DZ1, due to its own weight FG. Furthermore, at the contact point between the gear portion 81a and the frictional force applying portion 326a, a reaction force FG2 is generated due to the own weight FG. When the gear portion 81a rotates in the rotational direction CW, a frictional force F31 is generated due to the reaction force FG2. Furthermore, when the frictional force applying portion 326a elastically deforms, a resultant force F34 is generated, which is the sum of the frictional force F31 and the reaction force FG33. When the angle K30 is within the preferred range, the frictional force F31 or the resultant force F34 is greater than the force FG1. Therefore, the gear portion 81a can move in the direction of arrow E30 against the force FG1 due to the frictional force F31 or the resultant force F34.

[0689] On the other hand, when angle K30 is smaller than the lower limit of the preferred range, as shown in Figure 49(b), force FG1 increases and frictional force F31 or resultant force F34 decreases. As a result, frictional force F31 or resultant force F34 is smaller than force FG1 in the direction of arrow E31. Therefore, gear portion 81a cannot be moved in the direction of arrow E30. In other words, the tilted drive transmission member 81 cannot be moved to the engaged position, and the coupling cannot be engaged.

[0690] The friction force F31 or the component force F33 (see FIG. 47(b)) that is part of the resultant force 34 varies depending on the material used for the frictional force applying portion 326a, and is affected by the friction coefficient, surface softness, and tackiness of the material.

[0691] Lapping film (abrasive plastic film) is listed as a representative example of a material with a high coefficient of friction that does not elastically deform, that is, a material that is not an elastic member.

[0692] Double-sided tape is listed as a representative example of a material with high tackiness. Double-sided tape is one of the tacky materials that has tackiness. Since various materials with different softness can be used as the base material for double-sided tape, whether it is considered an elastic material or not depends on the selection of the base material.

[0693] Polyurethane foam is cited as a representative example of a material with a soft surface, that is, an elastic material.

[0694] Silicone sheets are also cited as a material that combines friction and softness, and are also a type of elastic material.

[0695] The preferable range on the lower limit side of the angle K30 becomes wider in the order of wrapping film, double-sided tape and silicone sheet, and polyurethane foam.

[0696] In this embodiment, when the cartridge B is mounted in the image forming apparatus main body A, the developing roller 32 is disposed at a position approximately 30° counterclockwise from the direction of gravity DZ1 in the circumferential direction centered on the rotation axis Ax1 of the drum 62. In other words, when viewed along the axis Ax1 of the drum 62, a line extending from the axis Ax1 of the drum 62 and passing through the axis of the developing roller 32 forms an angle of 30° counterclockwise with a line extending in the direction of gravity DZ1.

[0697] If the developing roller 32 of the cartridge B to which this embodiment is applied is not positioned at the angle of 30°, the preferred range of angle K30 increases or decreases by the difference in angle. For example, if the developing roller 32 is positioned at an angle of 20° counterclockwise from the direction of gravity DZ1 with respect to the rotation axis Ax1 of the drum 62, the preferred range of angle K30 when a wrapping film is used for the frictional force applying portion 326a is from −10° to 90°.

[0698] As explained above, the preferred ranges of the distance L30 and the angle K30 are set so that the coupling can be engaged. These values ​​depend on the configuration of the image forming apparatus main body A to which this embodiment is applied. Depending on the configuration of the image forming apparatus main body A to which this embodiment is applied, the preferred ranges of the distance L30 and the angle K30 are not limited to these.

[0699] The coefficients of friction of the members exemplified as those that can be used for the frictional force applying portion 336a are as follows: The coefficient of friction of polyurethane foam is 2.61, the coefficient of friction of a silicone sheet is 0.87, and the coefficient of friction of a wrapping film is 0.75.

[0700] For comparison, the coefficients of friction of the cartridge frame are as follows:

[0701] The coefficient of friction of the POM resin that constitutes the frame portion that supports the drum 62 is 0.34. In this embodiment, the coefficient of friction of the frame portion that supports the drum 62 corresponds to the coefficient of friction of the drum bearing 73.

[0702] The coefficient of friction of the PS resin constituting the portion of the frame exposed to the outside is 0.46, which corresponds to the coefficient of friction of the cleaning frame 71 in this embodiment, for example.

[0703] In this way, the coefficient of friction of the frictional force imparting portion 336a is higher than the coefficient of friction of the cartridge frame. As mentioned above, the coefficient of friction of the portion of the frame exposed to the outside, for example, the cleaning frame 71, is often higher than the coefficient of friction of the bearing portion of the frame, i.e., the drum bearing 73. In this embodiment, the coefficient of friction of the frictional force imparting portion 336a is set even higher than the coefficient of friction of the portion of the frame exposed to the outside.

[0704] The coefficient of friction of the frictional force applying portion 336a is more than 1.5 times the coefficient of friction of the bearing portion of the frame.

[0705] The coefficient of friction of the frictional force applying portion 336a is more than 1.5 times the coefficient of friction of the portion of the frame exposed to the outside.

[0706] In this example, the method used to measure the coefficient of friction is shown in Figure 51(a). A small piece of the object to be measured (OJ) is placed on a slope (SL) prepared using an ABS resin plate. The inclination of the ABS resin slope (SL) is then increased, and the angle of the slope when the object to be measured (OJ) begins to slide along the slope (SL) is defined as θ. The value of tan θ is defined as the coefficient of friction of the object to be measured (OJ).

[0707] In this example, when an elastic member is used as the frictional force applying portion 336a, the degree of elasticity thereof was examined by the following method.

[0708] A probe (contact) CT having a surface area of ​​2 x 5 mm is pressed against a measurement object having an original thickness T1 of 3 mm for 10 seconds with a force Fms = 50 gf. When the amount of reduction in the thickness of the measurement object OJ is ΔT [mm], the value obtained by dividing ΔT [mm] by the original thickness T1 = 3 mm is the degree of deformation.

[0709] For example, when a polyurethane foam with an original thickness T1 of 3 mm is pressed by a measuring probe CT, the thickness T2 after deformation becomes 0.78 mm. The thickness reduction amount at this time is T1 - T2 = 2.22 mm, and the degree of deformation ΔT / T1 is 2.22 / 3 = 0.74. The degree of deformation of the silicone sheet is 0.02.

[0710] In this example, a member with a deformation degree of 0.01 or more was considered to be an elastic member. It is preferable to use an elastic member with a deformation degree of 0.9 or less. If an elastic member is more easily deformed than this, when it comes into contact with the gear portion 81a of the drive transmission member 81, the elastic member may bite deeply into the gear portion 81a and hinder the movement of the drive transmission member 81.

[0711] As described above, in this embodiment as well, by bringing the drive transmission member 81 into contact with the friction imparting portion 336a of the cartridge B, it is possible to bring the drive transmission member 81 close to the cartridge B and connect it to the cartridge B. In this embodiment, by using the friction imparting portion 336a, there is an advantage that the cartridge configuration can be simplified more than in the above-described embodiments.

[0712] Next, Example 4 will be described below using Figures 52 to 55. In particular, among the elements disclosed in this example, those corresponding to the components described in the previous examples will be given the same names as the components in the previous examples, and only the differences will be described. In this example, the direction along the rotation axis Ax1 of the drum 62 is the longitudinal direction D402, the side of the drive-side drum flange 263 is the drive side, and the side opposite the drive side is the non-drive side. The direction from the non-drive side to the drive side is the direction of arrow E40, and the direction from the drive side to the non-drive side is the direction of arrow E41.

[0713] First, the cartridge structure of this embodiment will be described with reference to Figures 52 and 53. Figure 52 is a perspective view of cartridge B.

[0714] 52, the cartridge B in this embodiment is made up of a cleaning unit 260 and a developing unit 420, similar to the first embodiment.

[0715] The elastic rotation member 490 is a cylindrical, rotatable member made of an elastically deformable material (elastic member) such as polyurethane foam, rubber, or elastomer. In this embodiment, ESH from Inoac Corporation or Moltopren from Inoac Corporation is used as the polyurethane foam. The outer diameter of the cylindrical portion is designated as outer diameter portion 490a, and its radius is 5.84 mm in this embodiment. The elastic rotation member 490 is mounted on the support shaft 32a of the developing roller 32 and is rotatable integrally with the developing roller 32. The elastic rotation member 490 may be configured to rotate relative to the support shaft 32a.

[0716] Next, the arrangement of the elastic rotation member 490 will be described with reference to Figure 53. As will be described in detail later, the elastic rotation member 490 is configured to mesh with the gear portion 81a of the drive transmission member 81 by elastic deformation, similar to the elastic moving member 2912a of Modification 2 of Example 2 (see Figure 40(b)). Therefore, the preferred arrangement of the elastic rotation member 490 roughly conforms to the preferred range of the elastic moving member 2912a. Below, matters specific to the elastic rotation member 490 will be described in particular detail.

[0717] Figure 53 shows the configuration of cartridge B. (a) is a view perpendicular to the rotation axis of the drum 62, and (b) is a cross-sectional view taken along the line X400-X400 in (a). Note that, for the sake of explanation, only the drum 62 and the drive-side drum flange 263 are shown in Figure 53(a) of the components that make up the cleaning unit 260. Similarly, (b) of Figure 53 only shows the drum 62, the developing roller 32, and the elastic rotation member 490. Furthermore, in addition to the arrangement of the elastic rotation member 490 in this embodiment, (b) of Figure 53(b) also shows a state in which the elastic rotation member 490 is arranged in the positive and negative directions of angle K40, which will be described later, for the sake of explanation. The angle in the positive direction is indicated by angle K40U, and the angle in the negative direction is indicated by angle K40L.

[0718] 53(a), in the longitudinal direction D402, as in the third embodiment, at least a portion of the elastic rotation member 490 is located further in the direction of arrow E40 than the tip end 263b1 of the coupling portion 263b of the driving-side drum flange 263. In other words, at least a portion of the elastic rotation member 490 is located further outward in the longitudinal direction than the tip end 263b1. In other words, at least a portion of the elastic rotation member 490 is located farther from the non-driving side of the cartridge B than the tip end 263b1.

[0719] In particular, in this embodiment, at least a portion of the elastic rotation member 490 is disposed within a range of 4 to 9 mm from the tip 263b1 toward the drive side. Note that the above range may be set even larger depending on the configuration of the drive side drum flange 263 and the configuration of the applicable image forming apparatus main body A.

[0720] 53(b) is a schematic diagram of the cartridge as viewed along the longitudinal direction D402. The direction of a straight line extending from the rotation axis Ax1 of the drum 62 to pass through the rotation axis Ax40 of the elastic rotation member 490 is defined as direction D400.

[0721] The arrow indicating direction D400 is a straight line perpendicular to the rotation axis Ax1 and the longitudinal direction D402. The distance from the axis of the drum 62 to the outer diameter portion 490a of the elastic rotation member 490 along direction D400 perpendicular to the rotation axis Ax1 is defined as distance L40. In this case, distance L40 is set to be in the range of 75% to 120% of the radius of the drum 62, similar to the case in Example 3 where the frictional force applying portion 326a is an elastic body. In this example, the radius of the drum 62 is 12 mm, and distance L40 is set to be 95.67% (11.48 mm) of the radius of the drum 62.

[0722] The line connecting the rotation axis Ax1 of the drum 62 and the rotation axis Ax2 of the developing roller 32 is used as a reference line, and the angle that the direction D400 makes with this reference line is defined as angle K40. The downstream direction of the direction of arrow R, which is the rotation direction of the drum 62, is defined as positive, and the upstream direction of the direction of arrow R is defined as negative. The preferred range of angle K40 is set to between -70° and 100°, similar to the case in Modification 2 of Example 2, where polyurethane foam is used for the elastic moving member. In this example, angle K40 is set to 0°. As in Example 3, the preferred ranges of angle K40 and distance L40 are determined based on the relationship with the image forming apparatus main body A to which they are applied.

[0723] In addition, in this embodiment, the elastic rotation member 490 is provided on the support shaft 32a of the developing roller 32, but this is not limited to this. The elastic rotation member 490 may be provided on a shaft provided on the developing side member 426 or the cleaning unit 260, depending on the settings of the angle K40 and the distance L40.

[0724] Next, the operation of driving the drive transmission member 81 until the coupling recess 81b engages with the coupling protrusion 263b of the driving-side drum flange 263 will be described with reference to Figure 54. Figure 54 is a cross-sectional view showing the operation when cartridge B is mounted and the drive transmission member 81 is driven, and the cross-sectional position corresponds to the X401-X401 cross section in Figure 53(a). (a) shows the state immediately after the drive transmission member 81 is driven after cartridge B has been mounted, and (b) shows the state after the drive transmission member 81 has moved to a position where it can engage with the driving-side drum flange 263.

[0725] As shown in FIG. 54A, when cartridge B is installed in image-forming apparatus main assembly A, the elastic rotation member 490 enters the space S40 between adjacent gear teeth of gear portion 81a, similar to the state in which polyurethane foam is used in Example 3. When the drive transmission member 81 rotates in the rotational direction CW in this state, the tooth surface 81a2 receives a reaction force F40 from the elastic rotation member 490, and the gear portion 81a moves in the direction of the reaction force F40. As the gear portion 81a moves, the rotation axis Ax3 approaches the rotation axis Ax1 of the drum 62. Thereafter, the gear portion 81a abuts against the restricting portion 73j, and as shown in FIG. 54B, the drive transmission member 81 becomes substantially coaxial with the drive-side drum flange 263. At this time, the coupling recess 81b and the coupling protrusion 263b also become substantially coaxial and are positioned for engagement.

[0726] At this time, the elastic rotation member 490 rotates in the rotation direction R40 due to a force F41 from the tooth surface 81a2 of the gear portion 81a.

[0727] 55, a thrust force F42 in the direction of arrow DW3 is generated on the tooth surface 81a2 of the helical gear portion 81a (shown hatched in the figure) by a reaction force F40 from the rotating elastic rotation member 490. This thrust force F42 moves the drive transmission member 81 in the direction of arrow DW3.

[0728] The subsequent engaging operation is the same as in the previous embodiment, and therefore a description thereof will be omitted.

[0729] Unlike the frictional force applying portion 326a described in the third embodiment, the elastic rotation member 490 of this embodiment moves the gear portion 81a of the drive transmission member 81 and receives a driving force from the gear portion 81a. The driving force received by the elastic rotation member 490 can be used as power for driving the developing roller 32 and other members of the cartridge B.

[0730] For example, in the first embodiment (see FIG. 9), the developing roller gear 30 is connected to the developing roller 32, and so the elastic rotation member 490 may be connected to the developing roller gear 30.

[0731] However, it is not always necessary for the elastic rotation member 490 to transmit the driving force received from the drive transmission member 81 to another member.

[0732] In this modification, the gear portion 81a of the drive transmission member 81 bites into the elastic rotation member 490, which is an elastic body, which has the advantage that the engagement state between the elastic rotation member 490 and the drive transmission member 81 is easily stabilized.

[0733] Next, Example 5 will be described below with reference to Figures 56 to 66. In particular, among the elements disclosed in this example, those corresponding to the components described in the previous examples will be given the same names as the components in the previous examples, and only the differences from the previous examples will be described. Note that in the description of this example, reference will be made particularly to Example 2.

[0734] First, the cartridge configuration of this embodiment will be described with reference to Figure 56. Figure 56 is a perspective view of cartridge B. As shown in Figure 56, cartridge B in this embodiment is composed of a cleaning unit 260 and a developing unit 520, as in Example 2. The developing unit 520 also has a partially toothed gear mechanism 590. In this embodiment, the direction along the rotation axis Ax1 of the drum 62 is the longitudinal direction D500, the drive side drum flange 263 side is the drive side, and the direction toward the drive side is indicated by arrow E50. The side opposite the drive side is the non-drive side, and the direction toward the non-drive side is indicated by arrow E51. <Partial Toothed Gear Mechanism>

[0735] Next, the configuration of the missing tooth gear mechanism 590 will be described with reference to Figure 57. Figure 57 is an exploded perspective view of the missing tooth gear mechanism 590. (a) is a view seen from the non-drive side, and (b) is a view seen from the drive side.

[0736] In this embodiment, the partially toothed gear mechanism 590 is provided on the drive side of the cartridge as part of the configuration of the developing unit 520 (see Figure 59(a)). As shown in Figure 57, the partially toothed gear mechanism 590 is made up of a drive-side developing side member 526, a partially toothed gear 591, a biasing spring 592, a torsion coil spring 594, a rotating member 295, a support member 596, a pressed member 297, and an initialization spring 298. Each of the components of the partially toothed gear mechanism 590 will be described below.

[0737] The drive-side developing side member 526 has, as components relating to the partially toothed gear mechanism 590, a shaft support portion 526a, a restriction hole 526b, a hole portion 526d, a spring seat surface 526h, a notch portion 526g, and a guide surface 526i.

[0738] The shaft support portion 526a is a hole recessed in the longitudinal direction D500, and its axis is the rotation axis Ax50. When the partly tooth-missing gear mechanism 590 is assembled, the rotation axis Ax2 of the developing roller 32 is arranged to be coaxial with the rotation axis Ax50 of the shaft support portion 526a.

[0739] The restriction hole 526b is a hole recessed in the longitudinal direction D500 and is an arc-shaped hole coaxial with the rotation axis Ax50. When viewed from the non-drive side parallel to the rotation axis Ax50, the counterclockwise direction centered on the rotation axis Ax50 is defined as the rotation direction R50, and the clockwise direction is defined as the rotation direction R51. The downstream end of the restriction hole 526b in the rotation direction R51 is defined as a restriction surface 526b1.

[0740] The hole 526d, spring seat 526h, notch 526g, and guide surface 526i are provided in the same manner as the hole 226d, spring seat 226h, notch 226g, and guide surface 226i of the second embodiment.

[0741] The chipped gear 591 is composed of a gear portion 591a, a shaft hole 591b, a small-diameter portion 591c, a large-diameter portion 591d, a pressed portion 591e, a spring hook hole 591f, and a locking protrusion 591g. When the chipped gear mechanism 590 is assembled, the chipped gear 591 has a shaft hole 591b coaxial with the rotation axis Ax50, and multiple gear portions 591a radially outward from the shaft hole 591b. The small-diameter portion 591c is provided downstream of the gear portion 591a in the rotation direction R50, and the large-diameter portion 591d is provided further downstream. The surface connecting the small-diameter portion 591c and the large-diameter portion 591d is the pressed portion 591e. The chipped gear 591 has a spring hook hole 591f at the end on the arrow E51 side and a locking protrusion 591g at the end on the arrow E50 side.

[0742] The partially-toothed gear 591 is a portion having at least one gear tooth. The partially-toothed gear 591 of this embodiment has a plurality of gear teeth. The partially-toothed gear 591 of this embodiment is a component corresponding to the gear portion 30a of the first embodiment (see FIG. 9). At least a portion of the partially-toothed gear 591 is exposed to the outside of the cartridge in order to mesh with the gear portion 81a of the drive transmission member 81. More specifically, the exposed portion of the gear portion 291a faces the side of the axis Ax1 of the drum 62 (see FIG. 56).

[0743] The biasing spring 592 is a torsion coil spring, and has an inner diameter portion 592a, a fixed arm 592b protruding in the direction of arrow E51, and an acting arm 592c protruding in the direction of arrow E50.

[0744] The torsion coil spring 594 is composed of an actuated arm 594a, an acting arm 594b, and an inner diameter portion 594c. A state in which no load is acting on the actuated arm 594a and the acting arm 594b is referred to as a free state. The acting arm 594b has an arm portion 594b1 extending radially outward and an acting portion 594b2 extending in the direction of arrow E50 from the free end of the arm portion 594b1. When viewed from direction D500, the side in which the actuated arm 294a and the acting arm 294b approach each other from the free state is referred to as a closing direction, and the side in which they move away from each other is referred to as an opening direction.

[0745] The rotating member 295 is the same as that in Example 2. In this example, the rotation axis of the rotating member 295 is the rotation axis line Ax51.

[0746] The support member 596 is composed of a hole 596a, a developing roller support hole 596b, a guide surface 596c, and a spring hook hole 596d, and is a member that is fixed to the drive-side developing side member 526 when the partly toothed gear mechanism 590 is assembled. The developing roller support hole 596b is a hole that penetrates in the longitudinal direction D500. The spring hook hole 596d is a hole that penetrates in the longitudinal direction D500. The hole 596a and the guide surface 596c have the same configurations as the hole 296a and the guide surface 596c in Example 2.

[0747] The pressed member 297 and the initialization spring 298 have the same configuration as in Example 2. <Assembly of the missing tooth gear mechanism>

[0748] Next, a method for assembling the partially toothed gear mechanism 590 and assembling the partially toothed gear mechanism 590 to the developing unit 520 will be described with reference to Figures 58 and 59. Figure 58 is a diagram showing a method for assembling the partially toothed gear mechanism 590. Assembly is performed in the order of Figures 58(a) and 58(b). Figure 59 is a diagram showing the partially toothed gear mechanism 590 in an assembled state. (a) is a view taken along a direction perpendicular to the longitudinal direction, (b) is a cross section taken along X503-X503 in (a), and (c) is a cross section taken along X504-X504 in (a).

[0749] First, as shown in Figure 58(a), the torsion coil spring 594 and the rotating member 295 are assembled to the drive-side developing-device side member 526. The torsion coil spring 594 has the acted-up arm 594a positioned in the gap 295c, and the shaft 295g of the rotating member 295 is inserted into the inner diameter portion 594c. The rotating member 295 is assembled in the direction of arrow E50 along direction D500, and the shaft 295g is rotatably supported in the hole 526d.

[0750] Next, the pressed member 297 and the initialization spring 298 are assembled, but since this is the same as in the second embodiment, the description thereof will be omitted.

[0751] Next, the partially toothed gear 591, the urging spring 592, and the support member 596 are assembled. As shown in FIG. 58B, the developing unit 520 has the developing roller 32. The support shaft 32a of the developing roller 32 is inserted through the developing roller support hole 596b of the support member 596, the inner diameter portion 592a of the urging spring 592, the shaft hole 591b of the partially toothed gear 591, and the shaft support portion 526a of the driving-side developing side member 526, in this order. As in the second embodiment, the support member 596 is inserted into the hole 596a over the shaft portion 295g of the rotating member 295, and is fixed to the driving-side developing side member 526 by adhesive or the like, with the guide surface 296c supporting the guided surface 297c of the pressed member 297 (see FIG. 27C).

[0752] The biasing spring 592 has its fixed arm 592b inserted into a spring hook hole 596d of the support member 596 and its operating arm 592c inserted into a spring hook hole 591f of the partly toothed gear 591.

[0753] The partially toothed gear 591 is rotatably supported by a shaft support portion 526a of the drive-side developer side member 526, and the locking protrusion 591g is inserted into a restriction hole 526b of the drive-side developer side member 526. At this time, the biasing spring 592 is assembled with the acting arm 592c twisted in the rotational direction R50 relative to the fixed arm 592b, and biases the partially toothed gear 591 in the rotational direction R51 with a moment M50. As shown in FIG. 59(b), this moment M50 causes the locking protrusion 591g of the partially toothed gear 591 to abut against the restriction surface 526b1 of the drive-side developer side member 526. Furthermore, as shown in FIG. 59(c), the large diameter portion 591d of the partially toothed gear 591 is in opposite phase to the acting portion 594b2 of the torsion coil spring 594 in the radial direction of the rotational axis Ax50.

[0754] Thereafter, the partially toothed gear mechanism 590 is fixed to the developing unit 520 with screws or the like, as shown in FIG. 59(a).

[0755] Through the above process, the partially toothed gear mechanism 590 is assembled into the developing unit 520.

[0756] Next, the range of existence of the missing tooth gear 591 of the missing tooth gear mechanism 590 will be described with reference to Figure 60. As will be described in detail later, the missing tooth gear 591 is a member configured to mesh with the gear portion 81a of the drive transmission member 81, similar to the developing roller gear 30 of Example 1. Therefore, the preferred arrangement of the missing tooth gear 591 conforms to the preferred arrangement of the developing roller gear 30.

[0757] As will be described in detail later, the partially-toothed gear 591 is a rotatable member. The following description will be given on the assumption that the partially-toothed gear 591 is in its initial position before the cartridge is mounted in the main body of the apparatus, i.e., in a position where it can mesh with the drive transmission member 81.

[0758] FIG. 60 shows the arrangement of the missing-tooth gear 591 of the missing-tooth gear mechanism 590. FIG. 60A is a view taken along a direction perpendicular to the rotation axis of the drum 62, and FIG. 60B is a cross-sectional view taken along the line X500-X500 in FIG. Note that, for the sake of explanation, FIG. 60A shows only the drum 62 and the drive-side drum flange 263 of the components constituting the cleaning unit 260. Similarly, FIG. 60B shows only the drum 62, the developing roller 32, and a portion of the missing-tooth gear 591. In addition to the arrangement of the missing-tooth gear 591 in this embodiment, FIG. 60B also shows a state in which the missing-tooth gear 591 is arranged in the positive and negative directions of angle K50, which will be described later, for the sake of explanation. The angle in the positive direction is indicated by angle K50U, and the angle in the negative direction is indicated by angle K50L.

[0759] The preferred arrangement of the missing tooth gear 591 is similar to the preferred arrangement of the developing roller gear 30 (see Figures 1, 9, and 20) described in Example 1 and the preferred arrangement of the rack gear 291 (see Figure 29(b)) described in Example 2.

[0760] For example, it is desirable that at least a portion of the chipped gear 591 be disposed outward in the longitudinal direction from the tip end portion 263b1 of the drive-side drum flange 263. It is also desirable that the teeth of the chipped gear 591 be exposed so as to face the drum axis Ax1.

[0761] When viewing the cartridge along the rotation axis Ax1, the direction of a straight line extending from the rotation axis Ax1 of the drum 62 to pass through the rotation axis Ax50 of the missing-tooth gear 591 is defined as direction D501. Direction D501 is perpendicular to the rotation axis Ax1. In this direction D501, the distance from the axis of the drum 62 to the tip of the gear teeth (tooth tip) of the gear portion 591a is defined as distance L50. As in the second embodiment, distance L50 is set to be in the range of 90% to 120% of the radius of the drum 62. Note that L50 is more preferably 90% to 110%, and even more preferably 93% to 107%.

[0762] Furthermore, a straight line extending from the rotation axis Ax1 of the drum 62 and passing through the rotation axis Ax2 of the developing roller 32 is used as a reference line, and the angle that direction D501 makes with respect to this reference line is defined as angle K50. As before, the downstream direction of the rotation of the drum 62 is defined as the positive direction of the angle. In other words, angle K50 is defined as positive on the downstream side in the direction of arrow R, which is the rotation direction of the drum 62, and negative on the upstream side in the direction of arrow R with respect to the reference line.

[0763] In this case, it is preferable that the partially toothed gear 591 is disposed so that the angle K50 is in the range of −75° to 50°. The preferable range of the angle K50 for the partially toothed gear 591 is the same as the preferable range of the angle K20 in the second embodiment (see FIG. 29(b)).

[0764] Also, the angle that a straight line extending from the rotation axis Ax1 of the drum 62 and passing through the tooth tip 591a1 of the gear portion 591a of the missing tooth gear 591 makes with respect to the reference line is defined as angle K51.

[0765] The positive direction of angle K51 is the downstream direction of the rotation of the drum 62. That is, the downstream side of angle K51 in the direction of arrow R, which is the rotation direction of the drum 62, is positive, and the upstream side of angle K51 in the direction of arrow R is negative. The preferred range of angle K51 is the same as the preferred range of angle K21 (see FIG. 29(b)) described in the second embodiment.

[0766] This is a favorable condition for meshing between the gear portion 81a (see FIG. 13) of the drive transmission member 81 and the gear portion 591a of the partly tooth-missing gear 591. It is also favorable to arrange the gear portion 591a of the partly tooth-missing gear 591 so that the angle K51 of at least one tooth falls within the above-mentioned favorable range.

[0767] In this embodiment, the missing tooth gear 591 is arranged so that the angle K51 is in the range of -35° or more and 45° or less.

[0768] In this embodiment, the partially toothed gear mechanism 590 is provided in the developing unit 520, but it may be provided in the cleaning unit 260 depending on the settings of the angle K50, the angle K51, and the distance L50.

[0769] In this embodiment, the partially toothed gear 591 is provided coaxially with the developing roller 32, but it does not have to be coaxial. In this case, the partially toothed gear 591 is supported by the driving side developing side member 526 or the like, rather than the support shaft 32a of the developing roller 32. <Operation of partially toothed gear mechanism>

[0770] Next, the operation of the partially toothed gear mechanism 590 will be described with reference to FIG.

[0771] 61 is an operation diagram of the partially toothed gear mechanism 590, showing a cross section taken along line X501-X501 in FIG. 60(a). Also, (a) shows the partially toothed gear mechanism 590 in a standby state, and (b) shows the partially toothed gear mechanism 590 in an operating state.

[0772] First, the standby state (non-operating state) of the partially-toothed gear mechanism 590 will be described with reference to FIG. 61( a). In the standby state of the partially-toothed gear mechanism 590, as in the second embodiment, the pressed member 297 is biased in the direction of arrow E25 along the third movable direction D203, and is positioned at a first position protruding in the direction of arrow E25. At this time, as in the second embodiment, the rotating member 295 is biased in a rotational direction Q51 about the rotation axis Ax51, and the torsion coil spring 594 is biased in a rotational direction Q53 about the rotation axis Ax52. At this time, the actuated arm 594a and the acting arm 594b of the torsion coil spring 594 are free. The acting portion 594b2 of the torsion coil spring 594 is positioned radially away from the large-diameter portion 591d of the partially-toothed gear 591 by a gap S50 in the radial direction about the rotation axis Ax50. This state is referred to as the standby state of the partially-toothed gear mechanism 590.

[0773] Next, the operating state of the partially toothed gear mechanism 590 will be described with reference to FIG. 61B. When the cartridge B is mounted in the image forming apparatus main assembly A, the pressed member 297 is pressed by the contact portion 15m of the drive side plate 15 (see FIG. 31A) and moves in the direction of arrow 24, as in the second embodiment. This causes the rotating member 295 to rotate in a rotational direction Q52 about the rotational axis Ax51. As the shaft portion 295g of the rotating member 295 rotates, the actuated arm 594a of the torsion coil spring 594 is urged in a rotational direction Q54 about the rotational axis Ax53 and is spring-charged. As a result, the acting portion 594b2 of the torsion coil spring 594 abuts against the large-diameter portion 591d of the partially toothed gear 591, applying a force F50. This state is referred to as the operating state of the partially toothed gear mechanism 590. Although details will be described later, the activated state is a state in which the torsion coil spring 594 can lock the rotational movement of the missing tooth gear 591. <Installation of the cartridge into the main body of the image forming apparatus>

[0774] Next, the operation of mounting the cartridge B in this embodiment into the image forming apparatus main body A will be described with reference to Figure 62. Figure 62 is a cross-sectional view showing the mounting operation of the cartridge B into the image forming apparatus main body A, and the cross-sectional position corresponds to the X501-X501 cross section in Figure 60(a). Also, (a) shows the state immediately before mounting the cartridge, and (b) shows the state after mounting the cartridge.

[0775] As shown in Figure 62(a), when the cartridge B is in a state immediately before being mounted in the image forming apparatus main body A, the pressed surface 297a of the pressed member 297 faces the abutment portion 15m of the drive side plate 15 that constitutes the image forming apparatus main body A. At this time, the partially toothed gear mechanism 590 is in a standby state. Also, the gear portion 591a of the partially toothed gear 591 is about to mesh with the gear portion 81a of the drive transmission member 81. In this state, the position of the partially toothed gear 591 in the cartridge may be referred to as the initial position, engagement position, operating position, pre-movement position, etc.

[0776] When the cartridge B moves from this position in the mounting direction C, the cartridge B reaches the state after mounting as shown in Figure 62(b).

[0777] Here, the partially toothed gear 591, which is in the initial position, is restricted from rotating in the rotation direction R51 (see FIG. 59(b)). Therefore, the gear portion 81a of the drive transmission member 81 and the gear portion 591a of the partially toothed gear 591 come into contact with each other. At this time, as in the second embodiment, the gear portion 81a is inclined in the escape direction DW2. Thereafter, the drive transmission member 81 moves under its own weight and meshes with the gear portion 591a of the partially toothed gear 591.

[0778] On the other hand, when the cartridge B is mounted in the image forming apparatus main body A, the pressed member 297 is pressed by the abutting portion 15m of the drive side plate 15 and moved to the second position. As a result, the partially toothed gear mechanism 590 is put into an operating state. <Engagement operation of the drive transmission member 81>

[0779] Next, the operation of the drive transmission member 81 until the coupling recess 81b engages with the coupling protrusion 263b of the drive-side drum flange 263 when the drive transmission member 81 is driven will be described with reference to Figures 63 and 64. Note that Figure 63 is a cross-sectional view showing the operation when the drive transmission member 81 is driven, and the cross-sectional position corresponds to the X501-X501 cross-section in Figure 60(a). (a) shows the drive transmission member 81 being driven in an inclined state, and (b) shows the drive transmission member 81 immediately after being aligned with the rotation axis Ax1 of the drum 62. Figure 64 is a cross-sectional view showing the operation of the partially toothed gear mechanism 590 after the drive transmission member 81 is aligned with the rotation axis Ax1 of the drum 62, and the cross-sectional position corresponds to the X501-X501 cross-section in Figure 60(a). (a) shows the process by which the partially toothed gear 591 is restricted in rotation by the acting arm 594b of the torsion coil spring 594, and (b) shows the state in which movement is restricted.

[0780] As shown in Figure 63(a) , when the drive transmission member 81 rotates in the rotational direction CW, as in Example 2, the gears mesh with each other, generating a meshing reaction force FD50 in the gear portion 81a, which is a reaction force to the meshing force FD1. At this stage, the tilted gear portion 81a can move in the direction of the meshing reaction force FD50, so not much force is transmitted to the gear portion 591a, and the meshing force FD1 is very small. Therefore, the moment M51 acting on the missing tooth gear 591 due to the meshing force FD1 is sufficiently smaller than the moment M50 due to the biasing spring 592, and the missing tooth gear 591 does not rotate in the rotational direction R50. The missing tooth gear 59 maintains its initial position, just as it was before meshing with the drive transmission member 81.

[0781] Meanwhile, the gear portion 81a of the drive transmission member 81 moves due to a reaction force FD50 of the meshing force FD1. As the gear portion 81a moves, the rotation axis Ax3 moves in a direction that coincides with the rotation axis Ax1 of the drum 62.

[0782] Then, as shown in FIG. 63(b), the gear portion 81a abuts against the restricting portion 73j, and the rotation axis Ax3 of the drive transmission member 81 and the rotation axis Ax1 of the drum 62 become substantially coaxial.

[0783] Thereafter, the engagement operation between the coupling protrusion 263b and the coupling recess 81b is the same as in the second embodiment, and therefore a description thereof will be omitted.

[0784] As shown in FIG. 63( b), when the gear portion 81a of the drive transmission member 81 abuts against the restricting portion 73j or when the coupling recess 81b engages with the coupling protrusion 263b, movement of the gear portion 81a in directions other than the rotational direction is restricted. When movement of the drive transmission member 81 is restricted, force can be sufficiently transmitted from the gear portion 81a to the gear portion 591a of the partially toothed gear 591. Therefore, if the force received by the gear portion 591a due to the meshing force between the gears at this time is defined as meshing force FD2, the moment M52 acting on the partially toothed gear 591 due to meshing force FD2 is greater than the moment M50 biased by the biasing spring 592. Therefore, the partially toothed gear 591 rotates in the rotational direction R50 due to moment M52 from the initial position (engaged position).

[0785] When the partially toothed gear 591 rotates a certain amount in the rotational direction R50, as shown in FIG. 64( a), the acting portion 594b2 of the torsion coil spring 594 abuts against the pressed portion 591e of the partially toothed gear 591, and a force F50a is applied to the pressed portion 591e from the acting portion 594b2. Here, the moment M53a acting on the partially toothed gear 591 due to the force F50a is set to be larger than the moment M50a from the biasing spring 592. Therefore, the acting arm 594b of the spring-loaded torsion coil spring 594 rotates in the rotational direction Q24 about the rotational axis Ax53. Then, as shown in FIG. 64( b), the acting portion 594b2 approaches the rotational axis Ax50 of the partially toothed gear 591 and abuts against the small diameter portion 591c, stopping its rotation. During this time, the partially toothed gear 591 rotates in the rotational direction R50.

[0786] When the partially toothed gear 591 rotates in the rotational direction R50, the gear portion 591a is disengaged from the gear portion 81a of the drive transmission member 81. In this state, the pressed portion 591e of the partially toothed gear 591 receives a moment M53b from the acting portion 594b2 of the torsion coil spring 594. Here, the moment M53b is set to be equal to or greater than the moment M50b from the biasing spring 592. As a result, the rotation of the partially toothed gear 591 in the rotational direction R51 is restricted by the acting portion 591b2 of the torsion coil spring 594. In other words, the gear portion 591a is maintained in a disengaged state from the gear portion 81a of the drive transmission member 81. The position of the partially toothed gear 591 in the cartridge at this time will be referred to as the retracted position, non-engaged position, post-movement position, etc.

[0787] When the partially toothed gear 591 moves from the initial position (engaged position) to the retracted position (disengaged position), it is locked by the torsion coil spring 594. The torsion coil spring 594 is a locking member configured to lock the movement of the partially toothed gear 591. <Removing the Cartridge>

[0788] Next, the operation of removing cartridge B from the image forming apparatus main assembly A will be described with reference to Figure 65. Figure 65 is a cross-sectional view showing the operation of removing cartridge B, and the cross-sectional position corresponds to the X502-X502 cross section in Figure 60(a). (a) to (c) show the process. Note that in Figure 65(b), for the sake of explanation, unnecessary shapes are not shown, and the area around the missing tooth gear mechanism 590 is shown in an enlarged manner.

[0789] As shown in Figure 65(a), in order to remove the cartridge B, the cartridge B is moved in the direction opposite to the mounting direction C. At this time, as in the second embodiment, as shown in Figure 65(b), the pressed surface 297a of the pressed member 297 moves away from the abutting portion 15m of the drive side plate 15, and the pressed member 297 moves to the first position by the initialization spring 298.

[0790] The rotating member 295 rotates in a rotational direction Q51 around the rotational axis Ax51. At this time, the torsion coil spring 594 returns to its original position in the direction in which the actuated arm 594a and the acting arm 594b close, and the torsion coil spring 594 enters a free state. At this time, the acting portion 594b2 of the torsion coil spring 594 moves to a position farther away in the radial direction around the rotational axis Ax50 than the large-diameter portion 591d of the partially toothed gear 591. In this way, the actuated portion 594b2 of the torsion coil spring 594 and the pressed portion 591e of the partially toothed gear 591 are released from contact, and the partially toothed gear 591 rotates in a rotational direction R51 around the rotational axis Ax50 due to the moment M50 of the biasing spring 592.

[0791] 65(c), the partially toothed gear mechanism 590 is in a standby state. The standby state of the partially toothed gear mechanism 590 is a non-operating state in which the partially toothed gear 591 is not locked by the torsion coil spring 594, i.e., an unlocked state.

[0792] The pressed member 297 is an operating unit that is operated to switch the state of the partially toothed gear mechanism 590 between a standby state and an operating state. When the pressed member 297 is pressed, the torsion coil spring 594 is in an operating state in which it can lock the partially toothed gear 591.

[0793] After the above process, the cartridge B is removed from the image forming apparatus main body A. <Modification 1 of Embodiment 5>

[0794] An elastic member such as the elastic rotation member 490 described in the fourth embodiment can be applied to the gear portion 591a of the missing tooth gear 591 in this embodiment. Such modifications are shown below. For ease of explanation, the configuration described above will be referred to as a representative example of the fifth embodiment, and the configuration shown below will be referred to as a first modification of the fifth embodiment.

[0795] 66A and 66B are diagrams illustrating this modification, in which (a) is an exploded perspective view of the rotation mechanism 5901, and (b) is a cross-sectional view showing the engagement with the drive transmission member 81.

[0796] As shown in FIG. 66(a), an elastic member 5911a is provided on a rotating member 5911 (corresponding to the partially toothed gear 591 in this embodiment) of a rotating mechanism 5901 (corresponding to the partially toothed gear mechanism 590 in this embodiment).

[0797] In this modification, elastic member 5911a is made of an elastically deformable material such as polyurethane foam, rubber, elastomer, etc. Note that in this modification, polyurethane foams such as ESH manufactured by Inoac Corporation and Moltoprene manufactured by Inoac Corporation are used. Furthermore, if the surface of elastic member 5911a is designated as surface 5911a1, the distance from rotation axis Ax501 of rotating member 5911 to surface 5911a1 is set to 5.84 mm.

[0798] As shown in Figure 66 (b), the elastic member 5911a enters the space between adjacent gear teeth of the gear portion 81a of the drive transmission member 81 and deforms to fit the shape of the gear teeth. The deformed elastic member 6911a acts in the same way as the missing-tooth gear 591, moving the drive transmission member 81 and rotating the rotating member 5911 in the rotational direction R501 about the rotation axis Ax501. This results in the same operation as in this embodiment. Engagement is also possible with this configuration.

[0799] The elastic member 5911a is deformable by coming into contact with the drive transmission member 81. Therefore, the allowable range of the distance from the rotation axis Ax1 of the drum 62 to the elastic member 5911a is wider than the allowable range of the distance from the rotation axis Ax1 of the drum 62 to the tip of the tooth of the partly toothed gear 591.

[0800] The distance measured from the rotation axis Ax1 of the drum 62 to the tip of the tooth of the missing tooth gear 591 along a direction perpendicular to the axis Ax1 was preferably within the range of 90-120% of the radius of the drum 62, more preferably 90-110%.

[0801] In contrast, the distance measured from the rotation axis Ax1 of the drum 62 to the elastic member 5911a along a direction perpendicular to the axis Ax1 is preferably 75 to 120% of the radius of the drum 62.

[0802] In this embodiment, after the drive transmission member 81 is connected to the cartridge B, the engagement between the partly toothed gear 591 and the gear portion 81a of the drive transmission member 81 can be released (see Figure 64(b)). In other words, even when removing the cartridge B, the engagement between the partly toothed gear 591 and the drive transmission member 81 can be released. Therefore, it is unlikely that the partly toothed gear 591 will get caught on the drive transmission member 81, preventing removal of the cartridge B. This has the advantage that the user can easily remove the cartridge B.

[0803] Next, Example 6 will be described below with reference to Figures 67 to 73. In particular, among the elements disclosed in this example, those corresponding to the members described in the previous examples will be given the same names as the members in the previous examples, and only the differences from the previous examples will be described. Note that in this example, the rack gear in Example 2 is changed from translational motion to rotational motion.

[0804] First, the cartridge configuration of this embodiment will be described with reference to Figure 67. Figure 67 is a perspective view of cartridge B. As shown in Figure 67, cartridge B in this embodiment is composed of a cleaning unit 260 and a developing unit 620, similar to embodiment 2. The developing unit 620 also has a rotating rack gear mechanism 690. In this embodiment, the direction along the rotation axis Ax1 of the drum 62 is the longitudinal direction D600, the drive side drum flange 263 side is the drive side, and the direction toward the drive side is indicated by arrow E60. The side opposite the drive side is the non-drive side, and the direction toward the non-drive side is indicated by arrow E61. <Rotating rack gear mechanism>

[0805] Next, the configuration of the rotating rack gear mechanism 690 will be described with reference to Figure 68. Figure 68 is an exploded perspective view of the rotating rack gear mechanism 690. (a) is a view seen from the non-drive side, and (b) is a view seen from the drive side.

[0806] In this embodiment, the rotating rack gear mechanism 690 is provided as part of the configuration of the developing unit 620 (see Figure 69(b)). The detailed structure of the rotating rack gear mechanism 690 is shown in Figure 68. The rotating rack gear mechanism 690 is made up of a drive-side developing side member 626, a rotating rack gear 691, a tension spring 292, a locking member 293, a torsion coil spring 294, a rotating member 295, a support member 696, a pressed member 297, and an initialization spring 298. Each of the components of the rotating rack gear mechanism 690 will be described below.

[0807] The drive-side developing side member 626 is provided with a slide surface 626c, a retaining portion 626f, a hole 626d, a spring hook portion 626e, a spring seat surface 626h, a notch 626g, a guide surface 626i, and a locking surface 626j as components related to the rack gear mechanism 690.

[0808] The slide surface 626c, the anti-slip portion 626f, the hole portion 626d, the spring hook portion 626e, the spring seat surface 626h, the notch portion 626g, and the guide surface 626i have the same configuration as the slide surface 226c, the anti-slip portion 226f, the hole portion 226d, the spring hook po...

Claims

1. A cartridge comprising: a frame; a photosensitive drum supported by the frame and rotatable about an axis; and a rack located on a side of the cartridge in the axial direction of the photosensitive drum, the rack having one or more teeth configured to be at least partially exposed so as to face the axis of the photosensitive drum.

2. The cartridge according to claim 1, further comprising a coupling configured to transmit a driving force to said photosensitive drum, said coupling being located at an end of said photosensitive drum and at said side of said cartridge.

3. A cartridge as described in claim 2, wherein the end of the photosensitive drum is a first end, the photosensitive drum has a second end opposite the first end, and when measured along the axial direction of the photosensitive drum, the one or more teeth are at least partially positioned farther from the second end of the photosensitive drum than the tip of the coupling.

4. A cartridge as described in any one of claims 1 to 3, wherein the rack can be positioned so that the distance from the axis of the photosensitive drum to the tip of any of the one or more teeth, measured along a direction perpendicular to the axis of the photosensitive drum, is greater than or equal to 90% and less than or equal to 120% of the radius of the photosensitive drum.

5. A cartridge according to any one of claims 1 to 4, further comprising a movable member provided on the side of the cartridge, the movable member being movable so that the distance from a surface of the movable member to the axis of the photosensitive drum is changed.

6. A cartridge as described in claim 5, wherein the movable member is capable of being positioned such that, when viewed along the axis of the photosensitive drum, at least a portion of the photosensitive drum is positioned between the surface of the movable member and the rack.

7. A cartridge as described in claim 5 or 6, wherein the photosensitive drum has a first end and a second end opposite the first end, the cartridge further has a coupling configured to transmit a driving force to the photosensitive drum, the coupling being located at the first end of the photosensitive drum and at the side of the cartridge, and the movable member can be positioned such that at least a portion of the surface of the movable member is located farther from the second end of the photosensitive drum than the tip of the coupling when measured along the axial direction of the photosensitive drum.

8. A cartridge according to any one of claims 5 to 7, wherein said movable member is positionable such that, viewed along the axis of said photosensitive drum, said surface of said movable member is positioned adjacent to the circumferential surface of the photosensitive drum.

9. A cartridge according to any one of claims 5 to 8, wherein said movable member can be positioned so that the distance from said surface of said movable member to the axis of said photosensitive drum is less than 1.2 times the radius of said photosensitive drum.

10. A cartridge according to any one of claims 5 to 9, wherein said movable member can be positioned so that the distance from said surface of said movable member to the axis of said photoreceptor drum is greater than 1.25 times the radius of said photoreceptor drum.

11. A cartridge according to any one of claims 1 to 10, wherein the rack comprises a plurality of teeth, and the rack is configured to move along a straight line or a plane tangent to the tips of the teeth.

12. A cartridge according to any one of claims 1 to 11, wherein the rack has a plurality of teeth, and the distance from the axis of the photosensitive drum to a line passing through the tips of the plurality of teeth, measured along a direction perpendicular to the axis of the photosensitive drum, is greater than or equal to 90% and less than or equal to 120% of the radius of the photosensitive drum.

13. A cartridge as described in any one of claims 1 to 12, wherein when viewed along the axis of the photosensitive drum, with the downstream direction of the rotation of the photosensitive drum being the positive direction of the angle, the rack can be positioned so that a line extending in a direction perpendicular to the movement direction of the rack away from the photosensitive drum forms an angle of -75° or more and 50° or less, or 130° or more and 190° or less, with respect to a line extending from the axis of the photosensitive drum through the axis of the developing roller.

14. A cartridge as described in any one of claims 1 to 13, wherein when viewed along the axis of the photosensitive drum, with the downstream direction of rotation of the photosensitive drum being the positive direction of the angle, the rack can be positioned so that a line extending from the axis of the photosensitive drum through any of the one or more teeth forms an angle of -75° or more and 50° or less, or 130° or more and 190° or less, with a line extending from the axis of the photosensitive drum through the axis of the developing roller.

15. A cartridge according to any one of claims 1 to 14, wherein the rack is movable between a first position and a second position, and further comprising a lock configured to inhibit movement of the rack between the first position and the second position.

16. The cartridge of claim 15, wherein the rack is biased toward the first position.

17. The cartridge of claim 15, wherein the lock is configured to inhibit movement of the rack when the rack is in the second position.

18. A cartridge according to any one of claims 15 to 17, wherein the lock is configured to be switchable between an activated state in which the lock can prevent movement of the lock, and an inactivated state in which the lock does not prevent movement of the rack.

19. The cartridge of claim 18, further comprising an actuator configured to switch said lock between an activated state and an inactivated state.

20. A cartridge according to any one of claims 1 to 18, further comprising a movable member located on the side of the cartridge, the movable member being movable so that the distance from a surface of the movable member to the axis of the photosensitive drum is changed.

21. A cartridge as described in claim 20, wherein the movable member is positionable such that, when viewed along the axis of the photosensitive drum, at least a portion of the photosensitive drum is located between a surface of the movable member and the surface of the rack.

22. A cartridge as described in claim 20 or 21, wherein the photosensitive drum has a first end and a second end opposite to the first end, the cartridge further has a coupling configured to transmit a driving force to the photosensitive drum, the coupling being located at the first end of the photosensitive drum and at the side of the cartridge, and the movable member can be positioned such that, when measured along the axial direction of the photosensitive drum, at least a portion of the surface of the movable member is located farther from the second end of the photosensitive drum than the tip of the coupling.

23. A cartridge according to any one of claims 20 to 22, wherein said movable member can be positioned such that, when viewed along the axis of said photosensitive drum, said surface of said movable member is positioned adjacent to the circumferential surface of the photosensitive drum.

24. A cartridge according to any one of claims 20 to 23, wherein the movable member can be positioned so that the distance from the surface of the movable member to the axis of the photoreceptor drum is less than 1.2 times the radius of the photoreceptor drum.

25. A cartridge according to any one of claims 20 to 24, wherein the movable member can be positioned so that the distance from the surface of the movable member to the axis of the photoreceptor drum is greater than 1.25 times the radius of the photoreceptor drum.

26. A cartridge having a frame body, a photosensitive drum supported by the frame body and rotatable about an axis, and an elastic body located on a side of the cartridge in the axial direction of the photosensitive drum, the elastic body having a surface configured to be at least partially exposed so as to face the axis of the photosensitive drum.

27. The cartridge of claim 26, wherein the elastic body is movable.

28. A cartridge as claimed in claim 26 or 27, wherein the elastic body is movable along the surface.

29. A cartridge according to any one of claims 26 to 28, wherein the elastic body is rotatable about its own axis.

30. A cartridge according to any one of claims 26 to 29, wherein the elastic body is movable so as to change the distance from the axis of the photosensitive drum to the surface of the elastic body.

31. The cartridge of claim 26, further comprising a movable lever on which the elastic body is provided.

32. The cartridge of any one of claims 26 to 31, further comprising a lock configured to inhibit movement of the elastic body.

33. The cartridge according to claim 32, wherein the lock can be switched between an actuated state in which the movement of the elastic body is restricted, and an inactuated state in which the movement of the elastic body is not restricted.

34. The cartridge of claim 33, further comprising an actuator configured to switch said lock between said activated and unactivated states.

35. A cartridge according to any one of claims 32 to 34, further comprising a spring for biasing the elastic body.

36. A cartridge as set forth in claim 35, wherein said elastic body is movable between a first position and a second position, said elastic body being biased toward said first position.

37. A cartridge according to any one of claims 32 to 36, wherein the lock is configured to prevent movement of the elastic body when the elastic body is in the second position.

38. A cartridge according to any one of claims 26 to 37, further comprising a coupling configured to transmit a driving force to the photosensitive drum, the coupling being located at an end of the photosensitive drum and at the side of the cartridge.

39. A cartridge described in any one of claims 26 to 38, wherein the end of the photosensitive drum is a first end, the photosensitive drum has a second end opposite the first end, and when measured along the axial direction of the photosensitive drum, at least a portion of the surface of the elastic body is located farther from the second end of the photosensitive drum than the tip of the coupling.

40. A cartridge as described in any one of claims 26 to 39, wherein the elastic body can be positioned so that the distance from the axis of the photosensitive drum to the surface of the elastic body, measured along a direction perpendicular to the axis of the photosensitive drum, is greater than or equal to 75% and less than or equal to 120% of the radius of the photosensitive drum.

41. A cartridge according to any one of claims 26 to 40, further comprising a movable member provided on the side of the cartridge, the movable member being movable so that the distance from a surface of the movable member to the axis of the photosensitive drum is changed.

42. A cartridge as described in claim 41, wherein the movable member is capable of being positioned such that, when viewed along the axis of the photosensitive drum, at least a portion of the photosensitive drum is positioned between the surface of the movable member and the surface of the elastic body.

43. A cartridge as described in any one of claims 41 to 42, wherein the photosensitive drum has a first end and a second end opposite the first end, the cartridge further has a coupling configured to transmit a driving force to the photosensitive drum, the coupling being located at the first end of the photosensitive drum and at the side of the cartridge, and the movable member can be positioned such that at least a portion of the surface of the movable member is located farther from the second end of the photosensitive drum than the tip of the coupling, when measured along the axial direction of the photosensitive drum.

44. A cartridge as claimed in any one of claims 41 to 43, wherein the movable member can be positioned such that, when viewed along the axis of the photoreceptor drum, the surface of the movable member is positioned adjacent to the circumferential surface of the photoreceptor drum.

45. A cartridge according to any one of claims 41 to 44, wherein the movable member can be positioned so that the distance from the surface of the movable member to the axis of the photoreceptor drum is less than 1.2 times the radius of the photoreceptor drum.

46. ​​A cartridge according to any one of claims 41 to 45, wherein the movable member can be positioned so that the distance from the surface of the movable member to the axis of the photoreceptor drum is greater than 1.25 times the radius of the photoreceptor drum.

47. A cartridge as described in any one of claims 26 to 46, wherein when viewed along the axis of the photosensitive drum, with the downstream direction of the rotation of the photosensitive drum being the positive direction of the angle, a line extending from the axis of the photosensitive drum through the surface of the elastic body forms an angle of -70° or more and 100° or less, or 130° or more and 190° or more, with a line extending from the axis of the photosensitive drum through the axis of the developing roller.

48. A cartridge comprising: a frame; a photosensitive drum supported by the frame and rotatable about an axis; and a friction force applying portion having a surface configured to be at least partially exposed so as to face the axis of the photosensitive drum, and located on a side of the cartridge in the axial direction of the photosensitive drum.

49. The cartridge of claim 48, wherein the frictional force applying portion is movable.

50. A cartridge according to claim 48 or 49, wherein the frictional force applying portion is movable so as to change the distance from the axis of the photosensitive drum to the surface of the frictional force applying portion.

51. A cartridge according to any one of claims 48 to 50, further comprising a movable lever provided with the frictional force applying portion.

52. A cartridge according to any one of claims 48 to 51, further comprising a coupling configured to transmit a driving force to the photoreceptor drum, the coupling being located at an end of the photoreceptor drum and at the side of the cartridge.

53. A cartridge as described in claim 52, wherein the end of the photosensitive drum is a first end, the photosensitive drum has a second end opposite the first end, and when measured along the axial direction of the photosensitive drum, at least a portion of the surface of the friction force applying portion is located farther from the second end of the photosensitive drum than the tip of the coupling.

54. A cartridge according to any one of claims 48 to 53, wherein the frictional force applying portion can be positioned so that the distance from the axis of the photosensitive drum to the surface of the frictional force applying portion is greater than or equal to 75% and less than or equal to 120% of the radius of the photosensitive drum, measured along a direction perpendicular to the axis of the photosensitive drum.

55. A cartridge according to any one of claims 48 to 54, wherein the coefficient of friction of the frictional force imparting portion is higher than the coefficient of friction of a portion exposed to the outside of the frame.

56. A cartridge as claimed in any one of claims 48 to 55, further comprising a movable member located on said side of said cartridge, said movable member being movable so that the distance from a surface of said movable member to the axis of said photosensitive drum is changed.

57. A cartridge as described in claim 56, wherein the movable member is capable of being positioned such that, when viewed along the axis of the photosensitive drum, at least a portion of the photosensitive drum is positioned between a surface of the movable member and the surface of the frictional force applying portion.

58. A cartridge as described in claim 56 or 57, wherein the photosensitive drum has a first end and a second end opposite to the first end, the cartridge further has a coupling configured to transmit a driving force to the photosensitive drum, the coupling being located at the first end of the photosensitive drum and at the side of the cartridge, and the movable member can be positioned such that at least a portion of the surface of the movable member is located farther from the second end of the photosensitive drum than the tip of the coupling, when measured along the axial direction of the photosensitive drum.

59. A cartridge as described in any one of claims 56 to 58, wherein the movable member can be positioned such that, when viewed along the axis of the photoreceptor drum, the surface of the movable member is positioned adjacent to the circumferential surface of the photoreceptor drum.

60. A cartridge as described in any one of claims 56 to 59, wherein the movable member can be positioned so that the distance from the surface of the movable member to the axis of the photoreceptor drum is less than 1.2 times the radius of the photoreceptor drum.

61. A cartridge as described in any one of claims 56 to 60, wherein the movable member can be positioned so that the distance from the surface of the movable member to the axis of the photoreceptor drum is greater than 1.25 times the radius of the photoreceptor drum.

62. A cartridge as described in any one of claims 48 to 61, wherein when viewed along the axis of the photosensitive drum, with the downstream direction of the rotation of the photosensitive drum being the positive direction of the angle, a line extending from the axis of the photosensitive drum through the surface of the frictional force imparting portion forms an angle of -70° or more and 100° or less, or 130° or more and 190° or less, with a line extending from the axis of the photosensitive drum through the axis of the developing roller.

63. A cartridge as described in any one of claims 48 to 62, wherein when viewed along the axis of the photosensitive drum, with the downstream direction of the rotation of the photosensitive drum being the positive direction of the angle, the normal to the surface of the frictional force imparting portion extending away from the axis of the photosensitive drum forms an angle of -70° or more and 100° or less, or 130° or more and 190° or less, with a line extending from the axis of the photosensitive drum through the axis of the developing roller.

64. A cartridge according to any one of claims 48 to 63, wherein the frictional force applying portion is an elastic body.

65. A cartridge according to any one of claims 48 to 63, wherein the frictional force applying portion is an abrasive material.

66. A cartridge according to any one of claims 48 to 63, wherein the frictional force imparting portion is a tacky member having tackiness.

67. A cartridge comprising: a frame; a photosensitive drum supported by the frame and rotatable about an axis; and a tacky member located on a side of the cartridge in the axial direction of the photosensitive drum, the tacky member having a surface configured to be at least partially exposed so as to face the axis of the photosensitive drum.

68. The cartridge of claim 67, wherein the tacky member is movable.

69. A cartridge as described in claim 67 or 68, wherein the tacky member is movable so as to vary the distance from the axis of the photoreceptor drum to the surface of the tacky member.

70. A cartridge according to any one of claims 67 to 69, further comprising a movable lever on which the tackable member is provided.

71. A cartridge according to any one of claims 67 to 70, further comprising a coupling configured to transmit a driving force to the photoreceptor drum, the coupling being located at an end of the photoreceptor drum and at the side of the cartridge.

72. A cartridge as described in claim 71, wherein the end of the photosensitive drum is a first end, the photosensitive drum has a second end opposite the first end, and at least a portion of the surface of the tacky member is located farther from the second end of the photosensitive drum than the tip of the coupling when measured along the axial direction of the photosensitive drum.

73. A cartridge as described in any one of claims 67 to 72, wherein the tacky member can be positioned such that the distance of the surface of the tacky member from the axis of the photoreceptor drum is greater than or equal to 75% and less than or equal to 120% of the radius of the photoreceptor drum, measured along a direction perpendicular to the axis of the photoreceptor drum.

74. A cartridge as described in any one of claims 67 to 73, further comprising a movable member located on said side of said cartridge, said movable member being movable so that the distance from a surface of said movable member to the axis of said photosensitive drum is changed.

75. A cartridge as described in claim 74, wherein the movable member is positionable such that, when viewed along the axis of the photoreceptor drum, at least a portion of the photoreceptor drum is positioned between a surface of the movable member and the surface of the tacky member.

76. A cartridge as described in claim 74 or 75, wherein the photosensitive drum has a first end and a second end opposite to the first end, the cartridge further has a coupling configured to transmit a driving force to the photosensitive drum, the coupling being located at the first end of the photosensitive drum and at the side of the cartridge, and the movable member can be positioned such that at least a portion of the surface of the movable member is located farther from the second end of the photosensitive drum than the tip of the coupling, when measured along the axial direction of the photosensitive drum.

77. A cartridge as described in any one of claims 74 to 76, wherein the movable member can be positioned such that, when viewed along the axis of the photoreceptor drum, the surface of the movable member is positioned adjacent to the circumferential surface of the photoreceptor drum.

78. A cartridge as described in any one of claims 74 to 77, wherein the movable member can be positioned so that the distance from the surface of the movable member to the axis of the photoreceptor drum is less than 1.2 times the radius of the photoreceptor drum.

79. A cartridge as described in any one of claims 74 to 78, wherein the movable member can be positioned so that the distance from the surface of the movable member to the axis of the photoreceptor drum is greater than 1.25 times the radius of the photoreceptor drum.

80. A cartridge as described in any one of claims 67 to 79, wherein, when viewed along the axis of the photosensitive drum, with the downstream direction of rotation of the photosensitive drum being the positive direction of the angle, a line extending from the axis of the photosensitive drum through the surface of the tacky member forms an angle of -70° or more and 100° or less, or 130° or more and 190° or less, with a line extending from the axis of the photosensitive drum through the axis of the developing roller.

81. A cartridge as described in any one of claims 67 to 80, wherein, when viewed along the axis of the photosensitive drum, with the downstream direction of rotation of the photosensitive drum being the positive direction of the angle, the normal to the surface of the tacky member extending away from the axis of the photosensitive drum forms an angle of -70° or more and 100° or less, or 130° or more and 190° or less, with a line extending from the axis of the photosensitive drum through the axis of the developing roller.

82. A cartridge comprising: a frame; a photosensitive drum supported by the frame and rotatable about its own axis; one or more movable teeth located on a side of the cartridge in the axial direction of the photosensitive drum and at least partially exposed to face the axis of the photosensitive drum; and a lock configured to inhibit movement of the one or more teeth.

83. A cartridge as described in claim 82, wherein the lock is switchable between an activated state that resists movement of the one or more teeth and an inactivated state that does not resist movement of the one or more teeth.

84. The cartridge of claim 83, further comprising an actuator configured to switch said lock between said activated and unactivated states.

85. A cartridge as claimed in claim 82 or 83, further comprising a spring biasing the one or more teeth.

86. A cartridge according to any one of claims 82 to 85, wherein the one or more teeth are movable between a first position and a second position and are biased towards the first position.

87. The cartridge of claim 86, wherein the lock is configured to inhibit movement of the one or more teeth with the one or more teeth in the second position.

88. The cartridge of claim 86, wherein the lock is configured to inhibit movement of the one or more teeth with the one or more teeth in the first position.

89. A cartridge as claimed in any one of claims 82 to 88, further comprising a gear having said one or more teeth.

90. The cartridge of claim 89, wherein the gear is a rack.

91. The cartridge of claim 89, wherein the gear is rotatable about its own axis.

92. The cartridge of claim 89, wherein the gear is a missing-tooth gear.

93. A cartridge according to any one of claims 82 to 92, further comprising a coupling configured to transmit a driving force to the photosensitive drum, the coupling being located at an end of the photosensitive drum and at the side of the cartridge.

94. A cartridge as described in claim 93, wherein the end of the photosensitive drum is a first end, the photosensitive drum has a second end opposite the first end, and at least a portion of the one or more teeth are located farther from the second end of the photosensitive drum than the tip of the coupling when measured along the axial direction of the photosensitive drum.

95. A cartridge as described in any one of claims 82 to 94, wherein the one or more teeth can be positioned such that, when measured along a direction perpendicular to the axis of the photosensitive drum, the distance from the axis of the photosensitive drum to the tip of the one or more teeth is greater than or equal to 90% and less than or equal to 120% of the radius of the photosensitive drum.

96. A cartridge as described in any one of claims 82 to 95, further comprising a movable member provided on the side of the cartridge, the movable member being movable so that the distance from a surface of the movable member to the axis of the photosensitive drum is changed.

97. A cartridge as described in claim 96, wherein the movable member is capable of being positioned such that, when viewed along the axis of the photosensitive drum, at least a portion of the photosensitive drum is positioned between a surface of the movable member and the gear.

98. A cartridge as described in claim 96 or 97, wherein the movable member is capable of being positioned so that, when viewed along the axis of the photosensitive drum, at least a portion of the photosensitive drum is positioned between the surface of the movable member and the surface of the elastic body.

99. A cartridge as described in any one of claims 96 to 98, wherein the photosensitive drum has a first end and a second end opposite the first end, the cartridge further has a coupling configured to transmit a driving force to the photosensitive drum, the coupling being located at the first end of the photosensitive drum and at the side of the cartridge, and the movable member can be positioned such that at least a portion of the surface of the movable member is located farther from the second end of the photosensitive drum than the tip of the coupling, when measured along the axial direction of the photosensitive drum.

100. A cartridge as described in any one of claims 96 to 99, wherein the movable member can be positioned such that, when viewed along the axis of the photoreceptor drum, the surface of the movable member is positioned adjacent to the circumferential surface of the photoreceptor drum.

101. A cartridge as described in any one of claims 96 to 100, wherein the movable member can be positioned so that the distance from the surface of the movable member to the axis of the photoreceptor drum is less than 1.2 times the radius of the photoreceptor drum.

102. A cartridge as described in any one of claims 96 to 101, wherein the movable member can be positioned so that the distance from the surface of the movable member to the axis of the photoreceptor drum is greater than 1.25 times the radius of the photoreceptor drum.

103. A cartridge as described in any one of claims 82 to 102, wherein when viewed along the axis of the photosensitive drum, with the downstream direction of rotation of the photosensitive drum being the positive direction of the angle, the one or more teeth can be positioned so that a line extending from the axis of the photosensitive drum through any of the one or more teeth forms an angle of -75° or more and 50° or less, or 130° or more and 190° or more, with respect to a line extending from the axis of the photosensitive drum through the axis of the developing roller.

104. A cartridge comprising: a frame; a photosensitive drum supported by the frame and rotatable about an axis; and a rotatable missing-tooth gear located on the side of the cartridge and having one or more teeth configured to be at least partially exposed to face the axis of the photosensitive drum.

105. The cartridge according to claim 104, further comprising a coupling configured to transmit a driving force to the photosensitive drum, the coupling being located at an end of the photosensitive drum and at the side of the cartridge.

106. A cartridge as described in claim 105, wherein said end of said photoreceptor drum is a first end, said photoreceptor drum has a second end opposite said first end, and at least a portion of said one or more teeth is located farther from said second end of said photoreceptor drum than the tip of said coupling when measured along the axial direction of said photoreceptor drum.

107. A cartridge as described in any one of claims 104 to 106, wherein the missing-tooth gear can be positioned so that the distance from the axis of the photosensitive drum to the tip of any of the one or more teeth, measured along a direction perpendicular to the axis of the photosensitive drum, is greater than or equal to 90% and less than or equal to 120% of the radius of the photosensitive drum.

108. A cartridge as described in any one of claims 104 to 107, further comprising a movable member located on said side of said cartridge, said movable member being movable so that the distance from a surface of said movable member to the axis of said photosensitive drum is changed.

109. A cartridge as described in claim 108, wherein the movable member can be positioned such that, when viewed along the axis of the photoreceptor drum, at least a portion of the photoreceptor drum is positioned between a surface of the movable member and the missing-tooth gear.

110. A cartridge as described in claim 108 or 109, wherein the photosensitive drum has a first end and a second end opposite the first end, the cartridge further has a coupling configured to transmit a driving force to the photosensitive drum, the coupling being located at the first end of the photosensitive drum and at the side of the cartridge, and the movable member can be positioned such that at least a portion of the surface of the movable member is located farther from the second end of the photosensitive drum than the tip of the coupling, when measured along the axial direction of the photosensitive drum.

111. A cartridge as described in claim 110, wherein the movable member is positionable such that, when viewed along the axis of the photoreceptor drum, the surface of the movable member is positioned adjacent to the circumferential surface of the photoreceptor drum.

112. A cartridge as described in any one of claims 108 to 111, wherein the movable member can be positioned so that the distance from the surface of the movable member to the axis of the photoreceptor drum is less than 1.2 times the radius of the photoreceptor drum.

113. A cartridge as described in any one of claims 108 to 112, wherein the movable member can be positioned so that the distance from the surface of the movable member to the axis of the photoreceptor drum is greater than 1.25 times the radius of the photoreceptor drum.

114. A cartridge as described in any one of claims 104 to 113, wherein when viewed along the axis of the photosensitive drum, with the downstream direction of the rotation of the photosensitive drum being the positive direction of the angle, a line extending from the axis of the photosensitive drum to pass through the axis of the missing tooth gear forms an angle of -75° or more and +50° or less, or an angle of 130° or more and 190° with respect to a line extending from the axis of the photosensitive drum to pass through the axis of the developing roller.

115. A cartridge as described in any one of claims 104 to 114, wherein the missing-tooth gear is rotatable between a first position and a second position, and further comprising a lock configured to inhibit movement of the missing-tooth gear between the first position and the second position.

116. The cartridge of claim 115, wherein the missing-tooth gear is biased toward the first position.

117. The cartridge of claim 115, wherein the lock is configured to prevent movement of the missing-tooth gear when the missing-tooth gear is in the second position.

118. The cartridge of claim 115, wherein the lock is configured to prevent movement of the missing-tooth gear when the missing-tooth gear is in the first position.

119. A cartridge according to any one of claims 115 to 118, wherein the lock can be switched between an activated state in which movement of the missing tooth gear is prevented, and an inactivated state in which movement of the missing tooth gear is not prevented.

120. A cartridge according to any one of claims 115 to 119, further comprising an actuator configured to switch said lock between an activated state and an inactivated state.

121. A cartridge according to any one of claims 115 to 120, wherein the locked state caused by the lock is released by rotating the gear with missing teeth.

122. A cartridge as described in any one of claims 104 to 121, wherein the missing-tooth gear is movable in its axial direction.

123. A cartridge comprising: a frame; a photosensitive drum supported by the frame and rotatable about an axis, the photosensitive drum having a first end and a second end opposite the first end; one or more movable teeth located on a side of the cartridge in the axial direction of the photosensitive drum and configured to be at least partially exposed toward the axis of the photosensitive drum; and a spring for biasing the one or more teeth, wherein when viewed along the axis of the photosensitive drum with the downstream direction of rotation of the photosensitive drum being the positive direction of the angle, a line extending from the axis of the photosensitive drum through any of the one or more teeth forms an angle of between -75° and 50°, or between 130° and 190°, with respect to a line extending from the axis of the photosensitive drum through the axis of the developing roller.

124. The cartridge of claim 123, further comprising a gear having said one or more teeth.

125. The cartridge of claim 124, wherein the spring biases the one or more teeth through the gear.

126. A cartridge according to any one of claims 123 to 125, further comprising a movable lever on which the one or more teeth are provided.

127. The cartridge of claim 126, wherein the spring biases the one or more teeth via the lever.

128. A cartridge according to any one of claims 123 to 127, further comprising a coupling positioned at an end of the photosensitive drum and configured to be capable of transmitting a driving force to the photosensitive drum.

129. A cartridge as described in claim 128, wherein the end of the photosensitive drum is a first end, the photosensitive drum has a second end opposite the first end, and the one or more teeth can be located at least partially farther from the second end of the photosensitive drum than the tip of the coupling when measured along an axial direction of the photosensitive drum.

130. A cartridge described in any one of claims 123 to 129, wherein the one or more teeth can be positioned such that, when measured along a direction perpendicular to the axis of the photosensitive drum, the distance from the axis of the photosensitive drum to the tip of any of the one or more teeth is greater than or equal to 90% and less than or equal to 120% of the radius of the photosensitive drum.

131. A cartridge comprising: a frame; a photosensitive drum supported by the frame and rotatable about an axis; one or more teeth located on a side of the cartridge in the axial direction of the photosensitive drum and configured to be at least partially exposed toward the axis of the photosensitive drum; and a movable lever provided with the one or more teeth, wherein the one or more teeth can be positioned such that, when viewed along the axis of the photosensitive drum with the downstream direction of rotation of the photosensitive drum being the positive angle direction, a line extending from the axis of the photosensitive drum through any of the one or more teeth forms an angle of between -75° and 50°, or between 130° and 190°, with respect to a line extending from the axis of the photosensitive drum through the axis of the developing roller.

132. The cartridge according to claim 131, further comprising a coupling configured to transmit a driving force to the photosensitive drum, the coupling being located at an end of the photosensitive drum and at the side of the cartridge.

133. A cartridge as described in claim 132, wherein the end of the photosensitive drum is a first end, the photosensitive drum has a second end opposite the first end, and the one or more teeth can be located at least partially farther from the second end of the photosensitive drum than the tip of the coupling when measured along an axial direction of the photosensitive drum.

134. A cartridge according to any one of claims 131 to 133, wherein the one or more teeth are movable between a first position and a second position, and further comprising a lock configured to inhibit movement of the one or more teeth between the first position and the second position.

135. The cartridge of claim 134, wherein the one or more teeth are biased toward the first position.

136. A cartridge as described in claim 134 or 135, wherein the lock is configured to resist movement of the rack with the one or more teeth in the second position.

137. A cartridge as described in claim 134 or 135, wherein the lock is configured to resist movement of the rack with the one or more teeth in the first position.

138. A cartridge as described in any one of claims 131 to 137, further comprising an actuator configured to switch between an activated state in which the lock can resist movement of the one or more teeth and an inactivated state in which the lock does not resist movement of the one or more teeth.

139. A cartridge as described in any one of claims 131 to 138, wherein the one or more teeth can be positioned such that, when measured along a direction perpendicular to the axis of the photoreceptor drum, the distance from the axis of the photoreceptor drum to the tip of any of the one or more teeth is greater than or equal to 90% and less than or equal to 120% of the radius of the photoreceptor drum.

140. A cartridge as claimed in any one of claims 131 to 139, wherein the one or more teeth are fixed to the lever.

141. A cartridge as claimed in any one of claims 131 to 140, in which the tip of the lever is one of the teeth.

142. A cartridge according to any one of claims 131 to 141, wherein the one or more teeth are movable in the axial direction of the photoreceptor drum.

143. A cartridge as described in any one of claims 131 to 142, wherein the one or more teeth are movable so that the distance of the one or more teeth from the axis of the photoreceptor drum varies.

144. A cartridge comprising: a frame; a photosensitive drum supported by the frame and rotatable about an axis, the photosensitive drum having a first end and a second end opposite the first end; and a rotatable gear located on a side of the cartridge in the axial direction of the photosensitive drum, the gear having one or more teeth configured to be at least partially exposed toward the axis of the photosensitive drum, the gear being movable in the axial direction of the photosensitive drum.

145. The cartridge described in claim 144, wherein when viewed along the axis of the photosensitive drum, with the downstream direction of rotation of the photosensitive drum being the positive direction of the angle, the gear can be positioned so that a line extending from the axis of the photosensitive drum through any of the one or more teeth forms an angle of -75° or more and 50° or less, or 130° or more and 190° or less, with a line extending from the axis of the photosensitive drum through the axis of the developing roller.

146. A cartridge as described in claim 144 or 145, including a spring biasing the gear.

147. The cartridge of claim 146, wherein the spring biases the one or more teeth through the gear.

148. A cartridge according to any one of claims 144 to 147, further comprising a lock to prevent movement of the gear.

149. The cartridge of claim 148, wherein the locked state of the gear by the lock is released by rotating the gear.

150. A cartridge according to any one of claims 144 to 149, further comprising a coupling positioned at an end of the photosensitive drum and configured to be capable of transmitting a driving force to the photosensitive drum.

151. A cartridge as described in claim 150, wherein the end of the photoreceptor drum is a first end and the photoreceptor drum has a second end opposite the first end, and the gear can be positioned such that the one or more teeth are at least partially located farther from the second end of the photoreceptor drum than the tip of the coupling when measured along an axial direction of the photoreceptor drum.

152. A cartridge as described in any one of claims 144 to 151, wherein the one or more teeth can be positioned such that, when measured along a direction perpendicular to the axis of the photoreceptor drum, the distance from the axis of the photoreceptor drum to the tip of any of the one or more teeth is greater than or equal to 90% and less than or equal to 120% of the radius of the photoreceptor drum.

153. A cartridge comprising: a frame; a photosensitive drum supported by the frame and rotatable about an axis; and a rotatable gear located on a side of the cartridge in the axial direction of the photosensitive drum and having one or more teeth configured to be at least partially exposed toward the axis of the photosensitive drum, wherein one of the frame and the gear has a hole portion, and the other has a shaft portion that fits into the hole portion, and the gear is movable in a direction perpendicular to its axis by a gap between the hole portion and the shaft portion.

154. The cartridge according to claim 153, further comprising a coupling positioned at an end of the photosensitive drum and configured to be capable of transmitting a driving force to the photosensitive drum.

155. A cartridge as described in claim 154, wherein the end of the photosensitive drum is a first end, the photosensitive drum has a second end opposite the first end, and the one or more teeth can be located at least partially farther from the second end of the photosensitive drum than the tip of the coupling when measured along an axial direction of the photosensitive drum.

156. A cartridge as described in any one of claims 153 to 155, wherein, when viewed along the axis of the photosensitive drum, with the downstream direction of rotation of the photosensitive drum being the positive direction of the angle, the gear can be positioned so that a line extending from the axis of the photosensitive drum through any of the one or more teeth forms an angle of -75° or more and 50° or less, or 130° or more and 190° or less, with a line extending from the axis of the photosensitive drum through the axis of the developing roller.

157. A cartridge as described in any one of claims 153 to 156, wherein the gear can be positioned so that the distance from the axis of the photoreceptor drum to the tip of any of the one or more teeth, measured along a direction perpendicular to the axis of the photoreceptor drum, is greater than or equal to 90% and less than or equal to 120% of the radius of the photoreceptor drum.

158. A cartridge comprising: a frame; a photosensitive drum supported by the frame and rotatable about an axis; and a rotatable belt having a surface configured to be at least partially exposed to the outside so as to face the axis of the photosensitive drum, the belt being located on a side of the cartridge in the axial direction of the photosensitive drum.

159. The cartridge described in claim 158, further comprising a coupling configured to transmit a driving force to the photosensitive drum, the coupling being located at an end of the photosensitive drum and at the side of the cartridge.

160. A cartridge as described in claim 159, wherein the end of the photosensitive drum is a first end, the photosensitive drum has a second end opposite the first end, and when measured along the axial direction of the photosensitive drum, at least a portion of the surface of the belt is located farther from the second end of the photosensitive drum than the tip of the coupling.

161. A cartridge as described in any one of claims 158 to 160, wherein the belt is elastic.

162. A cartridge as described in any one of claims 158 to 161, wherein the belt has one or more teeth on the surface.

163. A cartridge as described in any one of claims 158 to 162, wherein the belt can be positioned such that, when measured along a direction perpendicular to the axis of the photoreceptor drum, the distance from the axis of the photoreceptor drum to the surface of the belt is greater than or equal to 75% and less than or equal to 120% of the radius of the photoreceptor drum.

164. A cartridge as described in any one of claims 158 to 163, wherein the belt can be positioned so that the distance from the axis of the photoreceptor drum to the surface of the belt, measured along a direction perpendicular to the axis of the photoreceptor drum, is greater than or equal to 90% and less than or equal to 120% of the radius of the photoreceptor drum.

165. A cartridge as described in any one of claims 158 to 164, further comprising a movable member provided on the side, the movable member being movable so that the distance from the surface of the movable member to the axis of the photosensitive drum is changed.

166. A cartridge as described in claim 165, wherein the movable member is positionable such that, when viewed along the axis of the photoreceptor drum, at least a portion of the photoreceptor drum is located between a surface of the movable member and the belt.

167. A cartridge as described in claim 165 or 166, wherein the photosensitive drum has a first end and a second end opposite the first end, the cartridge further has a coupling configured to transmit a driving force to the photosensitive drum, the coupling being located at the first end of the photosensitive drum and on a side of the cartridge in the axial direction of the photosensitive drum, and the movable member can be positioned such that at least a portion of the surface of the movable member is located farther from the second end of the photosensitive drum than the tip of the coupling, when measured along the axial direction of the photosensitive drum.

168. A cartridge as described in any one of claims 165 to 167, wherein the movable member can be positioned such that, when viewed along the axis of the photoreceptor drum, the surface of the movable member is positioned adjacent to the circumferential surface of the photoreceptor drum.

169. A cartridge as described in any one of claims 165 to 168, wherein the movable member can be positioned so that the distance from the surface of the movable member to the axis of the photoreceptor drum is less than 1.2 times the radius of the photoreceptor drum.

170. A cartridge as described in any one of claims 165 to 169, wherein the movable member can be positioned so that the distance from the surface of the movable member to the axis of the photoreceptor drum is greater than 1.25 times the radius of the photoreceptor drum.

171. A cartridge as described in any one of claims 158 to 170, wherein when viewed along the axis of the photosensitive drum, with the downstream direction of rotation of the photosensitive drum being the positive direction of the angle, the belt can be positioned so that a line extending from the axis of the photosensitive drum through the surface of the belt forms an angle of -70° or more and 100° or less, or 130° or more and 190° or less, with a line extending from the axis of the photosensitive drum through the axis of the developing roller.

Images