Electrophotographic image forming apparatus, cartridge, and drum unit

Abstract

[Problem] To further develop conventional techniques. [Solution] A cartridge has a housing, a photosensitive drum, and a cover ring. The cover ring has a driving force receiving unit for receiving a driving force by engaging with a driving force applying member, a braking force receiving unit for receiving a braking force by engaging with a braking force applying member, and a guide portion for moving the braking force applying member with respect to the driving force applying member.

Description

[0001] This application is a divisional application of the invention patent application with the application date of March 17, 2020, application number 202080021684.7 (international application number PCT / JP2020 / 012811), and invention name “Electronic photographic imaging device, box and drum unit”. Technical Field

[0002] The present invention relates to an electrophotographic image forming apparatus using an electrophotographic method, such as a copier or printer, and a cartridge usable with the electrophotographic image forming apparatus. The present invention also relates to a drum unit usable with the electrophotographic image forming apparatus and the cartridge.

[0003] Here, an electrophotographic image forming apparatus (hereinafter, also referred to as an "image forming apparatus") is an apparatus that forms an image on a recording material by using an electrophotographic image forming method. Examples of image forming apparatuses include copiers, fax machines, printers (laser beam printers, LED printers, etc.), and multifunction printers thereof.

[0004] The cartridge is detachable from the main assembly of the image forming apparatus (apparatus main assembly). Examples of the cartridge include a process cartridge in which a photosensitive member and at least one of process devices acting on the photosensitive member are integrally formed as a cartridge.

[0005] The drum unit is a unit including a photosensitive drum, and is used for a cartridge or an image forming apparatus. Background Art

[0006] Conventionally, in the field of image forming apparatuses using electrophotographic forming processes, it is known that an electrophotographic photosensitive member (hereinafter referred to as a photosensitive drum) and a process device acting on the photosensitive drum are integrally formed as a cartridge. Such a cartridge is detachable from the main assembly of the image forming apparatus.

[0007] According to the cartridge method, maintenance of the imaging device can be performed by the user himself without relying on a service person, so that maintainability can be significantly improved. Therefore, this cartridge type is widely used in imaging devices.

[0008] In a structure in which a box can be mounted on and removed from an imaging device main component (device main component), there is a structure in which the main component and the box are connected by using a coupling to input a driving force from the device main component to the box (JP H8-328449).

[0009] The amount of torque required to drive the cartridge varies depending on the construction of the cartridge.

[0010] JP 2002-202690 proposes a structure of a cartridge including a load generating member that applies a load to the rotation of a photosensitive drum. The load generating member stabilizes the rotation of the photosensitive drum by increasing the torque of the photosensitive drum (JP 2002-202690). Summary of the Invention

[0011] The object of the present invention is to further develop the above-mentioned conventional technology.

[0012] An example of a cartridge according to the present application is a cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus, the main assembly including a driving force applying member and a braking force applying member, the cartridge comprising:

[0013] shell;

[0014] a photosensitive drum rotatably supported by the housing;

[0015] a coupling connected to the photosensitive drum so as to enable drive transmission,

[0016] The coupling comprises:

[0017] a driving force receiving portion for receiving a driving force for rotating the coupling by engaging with the driving force applying member, and

[0018] a braking force receiving portion for receiving a braking force for applying a load resisting rotation of the coupling by engaging with the braking force applying member, and

[0019] A guide portion is configured to move the braking force applying member relative to the driving force applying member.

[0020] An example of a drum unit according to the present application is a drum unit detachably mountable to a main assembly of an image forming apparatus, the main assembly including a driving force applying member and a braking force applying member, the drum unit including:

[0021] Photosensitive drum;

[0022] a coupling connected to the photosensitive drum so as to enable drive transmission,

[0023] The coupling comprises:

[0024] a driving force receiving portion for receiving a driving force for rotating the coupling by engaging with the driving force applying member, and

[0025] a braking force receiving portion for receiving a braking force for applying a load resisting rotation of the coupling by engaging with the braking force applying member, and

[0026] A guide portion is configured to move the braking force applying member relative to the driving force applying member.

[0027] Another example of the cartridge according to the present application is a cartridge comprising:

[0028] a housing having a first end portion and a second end portion opposite the first end portion;

[0029] a photosensitive drum rotatably supported by the first and second end portions of the housing; and

[0030] a coupling connected to the photosensitive drum so as to enable drive transmission, the coupling being provided adjacent to the first end portion of the housing,

[0031] wherein the coupling comprises a first shaped portion and a second shaped portion,

[0032] The first shaped portion has a portion located farther from the second end portion of the housing than the second shaped portion,

[0033] a distance measured along the axis direction of the coupling from the second end portion of the housing to the distal portion of the first shaped portion decreases toward downstream in the direction of rotational movement of the coupling,

[0034] The second forming portion has a first side portion at a position upstream in the rotational movement direction and a second side portion at a position downstream in the rotational movement direction, and

[0035] At least a portion of the second shaped portion is further away from the axis of the coupling in the radial direction of the coupling than a distal portion of the first shaped portion.

[0036] Another example of a drum unit according to the present application may be used with the cartridge, the drum unit comprising,

[0037] a photosensitive drum rotatably supported by the first end portion and the second end portion of the housing, and

[0038] a coupling connected to the photosensitive drum so as to enable drive transmission, the coupling being provided adjacent to a first end portion of the photosensitive drum,

[0039] wherein the coupling comprises a first shaped portion and a second shaped portion,

[0040] The first forming portion has a portion located farther from the second end portion of the photosensitive drum than the second forming portion,

[0041] a distance measured from the second end portion of the photosensitive drum to the away portion of the first forming portion along the axial direction of the coupling decreases toward downstream in a predetermined circumferential direction of the coupling,

[0042] The second shaped portion has a first side portion at a position upstream in the circumferential direction and a second side portion at a position downstream in the circumferential direction, and

[0043] At least a portion of the second shaped portion is further away from the axis of the coupling in the radial direction of the coupling than a distal portion of the first shaped portion.

[0044] Another example of the cartridge according to the present application is a cartridge comprising:

[0045] a housing having a first end portion and a second end portion opposite the first end portion;

[0046] a photosensitive drum rotatably supported by the first end portion and the second end portion of the housing;

[0047] a coupling disposed adjacent to the first end portion of the housing, the coupling being connected to the photosensitive drum so as to enable drive transmission,

[0048] The coupling comprises:

[0049] a first side portion facing upstream in the direction of rotational movement of the coupling;

[0050] a second side portion facing downstream in the direction of rotational movement; and

[0051] a guide portion extending so as to be closer to the second end portion of the housing toward downstream in the rotational movement direction of the coupling, the guide portion having a portion farther from the second end portion of the photosensitive drum than the first side portion in the axial direction of the coupling,

[0052] At least a portion of the first side portion is further away from the axis of the drum unit than a distal portion of the guide portion in a radial direction of the coupling.

[0053] Another example of the drum unit according to the present application is a drum unit including:

[0054] a photosensitive drum having a first end portion and a second end portion opposite the first end portion; and

[0055] a coupling disposed adjacent to the first end portion of the photosensitive drum, the coupling being connected to the photosensitive drum so as to enable drive transmission,

[0056] The coupling comprises:

[0057] a first side portion facing upstream in a predetermined circumferential direction of the coupling,

[0058] a second side portion facing downstream in the circumferential direction, and

[0059] a guide portion extending so as to be closer to the second end portion of the housing toward downstream in the circumferential direction, the guide portion having a portion farther away from the second end portion of the photosensitive drum than the first side portion in the axial direction of the coupling,

[0060] At least a portion of the first side portion is further away from the axis of the coupling in the radial direction of the coupling than a distal portion of the guide portion.

[0061] Another example of a cartridge according to the present application is a cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus, the main assembly including a driving force applying member and a braking force applying member movable relative to the driving force applying member, the cartridge comprising:

[0062] shell;

[0063] a photosensitive drum rotatably supported by the housing; and

[0064] a coupling connected to the photosensitive drum so as to enable drive transmission,

[0065] The coupling comprises:

[0066] a driving force receiving portion for receiving a driving force for rotating the coupling by engaging with the driving force applying member, and

[0067] A braking force receiving portion is configured to receive a braking force for applying a load resisting rotation of the coupling by engaging with the braking force applying member.

[0068] Another example of the drum unit according to the present application is a drum unit detachably mountable to a main assembly of an electrophotographic image forming apparatus, the main assembly including a driving force applying member and a braking force applying member movable relative to the driving force applying member, the drum unit comprising:

[0069] a photosensitive drum rotatably supported by the housing; and

[0070] a coupling connected to the photosensitive drum so as to enable drive transmission,

[0071] The coupling comprises:

[0072] a driving force receiving portion for receiving a driving force for rotating the coupling by engaging with the driving force applying member, and

[0073] A braking force receiving portion is configured to receive a braking force for applying a load resisting rotation of the coupling by engaging with the braking force applying member.

[0074] Furthermore, another example of the cartridge according to the present application includes one of the above-described drum units and a casing that supports the drum unit.

[0075] Furthermore, examples of the electrophotographic image forming apparatus according to the present application include any one of the above-described cartridges and a main assembly of the electrophotographic image forming apparatus.

[0076] Effects of the Invention

[0077] Conventional technology can be developed. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] Figure 1 is a perspective view of the drum coupling 143.

[0079] Figure 2 is a schematic cross-sectional view of an imaging apparatus.

[0080] Figure 3 is a cross-sectional view of the process cartridge.

[0081] Figure 4 is a cross-sectional view of an imaging device.

[0082] Figure 5 is a cross-sectional view of an imaging device.

[0083] Figure 6 is a cross-sectional view of an imaging device.

[0084] Figure 7 A detailed view of a part of the pallet.

[0085] Figure 8 It is a perspective view of a storage element pressing unit and a cartridge pressing unit.

[0086] Figure 9 is a partial perspective view of the imaging device.

[0087] Figure 10 It is a side view (partial sectional view) of the process cartridge.

[0088] Figure 11 is a cross-sectional view of an imaging device.

[0089] Figure 12 It is a perspective view of the development separation control unit.

[0090] Figure 13It is an assembled perspective view of the process cartridge.

[0091] Figure 14 is a perspective view of a process cartridge.

[0092] Figure 15 It is an assembled perspective view of the process cartridge.

[0093] Figure 16 It is an assembled perspective view of the process cartridge.

[0094] Figure 17 It is a view of the separation holding member R itself.

[0095] Figure 18 This is a view of the force applying member R itself.

[0096] Figure 19 It is a partial cross-sectional view of the separation holding member R after assembly.

[0097] Figure 20 It is an enlarged view of the periphery of the separation holding member R.

[0098] Figure 21 It is an enlarged view of the periphery of the separation holding member R.

[0099] Figure 22 It is a bottom view of the drive side of the process cartridge.

[0100] Figure 23 is a diagram illustrating the operation of the developing unit in the main assembly of the image forming apparatus.

[0101] Figure 24 is a diagram illustrating the operation of the developing unit in the main assembly of the image forming apparatus.

[0102] Figure 25 is a diagram illustrating the operation of the developing unit in the main assembly of the image forming apparatus.

[0103] Figure 26 is a diagram illustrating the operation of the developing unit in the main assembly of the image forming apparatus.

[0104] Figure 27 is a diagram illustrating the operation of the developing unit in the main assembly of the image forming apparatus.

[0105] Figure 28 It is a view of the separation holding member L itself.

[0106] Figure 29 This is a view of the force applying member L itself.

[0107] Figure 30 It is an assembled perspective view after the developing pressure spring is assembled and the separation holding member L is assembled.

[0108] Figure 31 It is a partial cross-sectional view of the separation holding member L after assembly.

[0109] Figure 32 It is an enlarged view of the periphery of the separation holding member L and the urging member L.

[0110] Figure 33 It is an enlarged view of the periphery of the separation holding member.

[0111] Figure 34 It is a side view as viewed from the driving side, with the process cartridge mounted inside the main assembly of the image forming apparatus.

[0112] Figure 35 is a diagram showing a process cartridge in the main assembly of the image forming apparatus.

[0113] Figure 36 is a diagram illustrating the operation of the developing unit in the main assembly of the image forming apparatus.

[0114] Figure 37 is a diagram illustrating the operation of the developing unit in the main assembly of the image forming apparatus.

[0115] Figure 38 is a diagram illustrating the operation of the developing unit in the main assembly of the image forming apparatus.

[0116] Figure 39 is a diagram illustrating the operation of the developing unit in the main assembly of the image forming apparatus.

[0117] Figure 40 2 is a diagram showing the arrangement of the separation holding member R and the urging member.

[0118] Figure 41 is a diagram showing the arrangement of a separation holding member and an urging member.

[0119] Figure 42 1 is a side view as viewed from the driving side with the process cartridge 100 mounted inside the main assembly of the image forming apparatus.

[0120] Figure 43 is an exploded perspective view of the drive transmission unit 203 .

[0121] Figure 44 is a cross-sectional view of the drive transmission unit 203 .

[0122] Figure 45 is a perspective view of the drive transmission unit 203 .

[0123] Figure 46 is a cross-sectional perspective view of a main assembly of the device including the drive transmission unit 203.

[0124] Figure 4714 is a front view of the drive transmission unit 203 and the drum coupling 143.

[0125] Figure 48 It is a developed view showing the engagement of the drum coupling.

[0126] Figure 49 It is a developed view showing the engagement of the drum coupling.

[0127] Figure 50 It is a developed view showing the engagement of the drum coupling.

[0128] Figure 51 is a cross-sectional view showing engagement of the drum coupling.

[0129] Figure 52 is a perspective view showing a modified example of the drum coupling.

[0130] Figure 53 It is a developed view showing the engagement of the drum coupling.

[0131] Figure 54 It is a developed view showing the engagement of the drum coupling.

[0132] Figure 55 is a perspective view of the drum unit showing the drum coupling.

[0133] Figure 56 is an illustration of a drum unit showing the drum coupling.

[0134] Figure 57 is a perspective view of the drum unit showing the drum coupling.

[0135] Figure 58 This is a top view of the drum coupling.

[0136] Figure 59 is a perspective view showing components of a drive transmission unit.

[0137] Figure 60 It is a perspective view of the drive transmission unit and the drum unit.

[0138] Figure 61 It is a perspective view of the drive transmission unit and the drum unit.

[0139] Figure 62 It is a perspective view of the drive transmission unit and the drum unit.

[0140] Figure 63 It is a perspective view of the drive transmission unit and the drum unit.

[0141] Figure 64 It is a perspective view of the drive transmission unit and the drum unit.

[0142] Figure 65It is a perspective view of the drive transmission unit and the drum unit.

[0143] Figure 66 It is a perspective view of the drive transmission unit and the drum unit.

[0144] Figure 67 It is a perspective view of the drive transmission unit and the drum unit.

[0145] Figure 68 It is a perspective view of the drive transmission unit and the drum unit.

[0146] Figure 69 It is a perspective view of the drive transmission unit and the drum unit.

[0147] Figure 70 It is a perspective view of the drive transmission unit and the drum unit.

[0148] Figure 71 It is a perspective view of the drive transmission unit and the drum unit.

[0149] Figure 72 It is a perspective view of the drive transmission unit and the drum unit.

[0150] Figure 73 is a perspective view showing a modified example of the drum coupling.

[0151] Figure 74 1 and 2 are perspective views and a front view showing a modified example of the drum coupling.

[0152] Figure 75 It is a perspective view of the drum unit.

[0153] Figure 76 It is a developed view showing the engagement of the drum coupling.

[0154] Figure 77 It is a perspective view of the drum unit and a front view of the coupling.

[0155] Figure 78 It is a perspective view of the drum unit and the drive transmission unit.

[0156] Figure 79 are side, perspective, and front views of the coupling.

[0157] Figure 80 It is a side view of the coupling.

[0158] Figure 81 are side and perspective views of the coupling.

[0159] Figure 82 is a schematic cross-sectional view of an imaging apparatus.

[0160] Figure 83 is a schematic sectional view of a process cartridge.

[0161] Figure 84 is a schematic perspective view of a process cartridge.

[0162] Figure 85 is a schematic perspective view of a process cartridge.

[0163] Figure 86 is a schematic cross-sectional view of the process cartridge taken along the rotation axis of the photosensitive drum.

[0164] Figure 87 is an exploded perspective view of the drive transmission unit 811.

[0165] Figure 88 It is a sectional view taken along the rotation axis of the drive transmission unit 811 mounted to the main assembly of the image forming apparatus.

[0166] Figure 89 is a schematic perspective view of another form of drum coupling 770.

[0167] Figure 90 701 is a schematic perspective view showing the mounting of the cartridge 701 to the image forming apparatus main assembly 800.

[0168] Figure 91 7 is a schematic sectional view illustrating an operation of mounting the cartridge 701 to the image forming apparatus main assembly 800.

[0169] Figure 92 770 is a schematic sectional view showing an operation of mounting the drum coupling 770 to the main assembly drive transmission unit 811.

[0170] Figure 93 770 is a schematic sectional view showing an operation of mounting the drum coupling 770 to the main assembly drive transmission unit 811.

[0171] Figure 94 is a perspective view showing another form of the process cartridge.

[0172] Figure 95 is a cross-sectional view of the drum unit.

[0173] Figure 96 is the front view of the coupling.

[0174] exist Figure 97 , part (a) is a perspective view of the coupling, and part (b) is a front view.

[0175] Figure 98 is the front view of the coupling.

[0176] Figure 99 It is a perspective view showing an engaged state of the coupling and the brake engaging member.

[0177] Figure 100is the front view of the coupling.

[0178] Figure 101 is the front view of the coupling.

[0179] Figure 102 are the front, perspective, and side views of the coupling.

[0180] Figure 103 It is a perspective view showing an engaged state of the coupling and the brake engaging member.

[0181] Figure 104 are perspective and side views of the drum unit.

[0182] Figure 105 It is a perspective view of the drum unit and a front view of the coupling.

[0183] Figure 106 is a cross-sectional view of the drum unit.

[0184] Figure 107 It is a perspective view of the drum unit.

[0185] Figure 108 It is a cross-sectional view of the coupling.

[0186] Figure 109 It is a perspective view of the drum unit.

[0187] Figure 110 It is a cross-sectional view of the drum unit and the drive transmission unit. DETAILED DESCRIPTION

[0188] <<Example 1>>

[0189] Hereinafter, the mode for implementing the present invention will be described in detail with reference to the accompanying drawings and examples. However, unless otherwise specified, the functions, materials, shapes, relative arrangements, etc. of the components described in this embodiment are not intended to limit the scope of the present invention thereto.

[0190] Hereinafter, Embodiment 1 will be described with reference to the accompanying drawings.

[0191] In the following embodiments, as the image forming apparatus, an image forming apparatus to which and from which four process cartridges are attachable and detachable is shown.

[0192] The number of process cartridges mounted on the image forming apparatus is not limited to this example and is appropriately selected as needed.

[0193] Furthermore, in the embodiments described below, a laser beam printer is exemplified as one aspect of the image forming apparatus.

[0194] [Schematic Structure of Imaging Device]

[0195] Figure 2: is a schematic cross-sectional view of the imaging device M. In addition, Figure 3 is a sectional view of the process cartridge 100 .

[0196] The image forming apparatus M is a four-color full-color laser printer using an electrophotographic process, and forms a color image on a recording material S. The image forming apparatus M is of a process cartridge type, and the process cartridge is detachably mounted to an image forming apparatus main assembly (apparatus main assembly, electrophotographic image forming apparatus main assembly) 170 to form a color image on a recording material S.

[0197] Here, regarding the imaging device M, the side where the front door 11 is provided is the front surface (front surface), and the surface opposite to the front surface is the rear surface (back surface). In addition, the right side of the imaging device M viewed from the front is referred to as the drive side, and the left side is referred to as the non-drive side.

[0198] Furthermore, when the imaging apparatus M is viewed from the front side, the upper side is an upper surface and the lower side is a lower surface. Figure 2 is a sectional view of the imaging device M viewed from the non-driving side; the front side of the paper in the figure is the non-driving side of the imaging device M; the right side of the paper in the figure is the front side; and the rear side of the paper in the figure is the driving side of the imaging device.

[0199] The driving side of the process cartridge 100 is a side on which a drum coupling (photosensitive member coupling) described below is provided in the axial direction of the photosensitive drum. In addition, the driving side of the process cartridge 100 is also a side on which a developing coupling described below is arranged in the axial direction of the developing roller (developing member).

[0200] The axial direction of the photosensitive drum is a direction parallel to the rotational axis of the photosensitive drum, which will be described below. Similarly, the axial direction of the developer roller is a direction parallel to the rotational axis of the developer roller, which will be described below. In this embodiment, the axis of the photosensitive drum and the axis of the developer roller are substantially parallel, and therefore, the axial direction of the photosensitive drum and the axial direction of the developer roller are considered to be substantially the same.

[0201] The image forming apparatus main assembly 170 has four process cartridges 100 ( 100Y, 100M, 100C, 100K), ie, a first process cartridge 100Y, a second process cartridge 100M, a third process cartridge 100C, and a fourth process cartridge 100K, arranged almost horizontally.

[0202] Each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) has the same electrophotographic process mechanism and has different colors of developer (hereinafter referred to as toner). A rotational driving force is transmitted from a drive output portion (details will be described below) of the image forming apparatus main assembly 170 to the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K).

[0203] Further, a bias voltage (charging bias, developing bias, etc.) is supplied from the image forming apparatus main assembly 170 to each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) (not shown).

[0204] like Figure 3 As shown in FIG. 1 , each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) of the present embodiment includes a photosensitive drum 104 and a drum holding unit 108 provided with a charging device serving as a process device that acts on the photosensitive drum 104. Furthermore, each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) includes a developing unit 109 provided with a developing device for developing the electrostatic latent image on the photosensitive drum 104.

[0205] The drum holding unit 108 and the developing unit 109 are coupled to each other. A more specific structure of the process cartridge 100 will be described hereinafter.

[0206] The first process cartridge 100Y contains yellow (Y) toner in the developing frame 125 and forms a yellow toner image on the surface of the photosensitive drum 104 .

[0207] The second process cartridge 100M contains magenta (M) toner in the developing frame 125 and forms a magenta toner image on the surface of the photosensitive drum 104 .

[0208] The third process cartridge 100C contains cyan (C) toner in the developing frame 125 and forms a cyan toner image on the surface of the photosensitive drum 104 .

[0209] The fourth process cartridge 100K contains black (K) toner in the developing frame 125 and forms a black toner image on the surface of the photosensitive drum 104. A laser scanner unit 14, which serves as an exposure device, is provided above the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K). The laser scanner unit 14 outputs a laser beam U corresponding to image information. The laser beam U passes through the exposure window 110 of the process cartridge 100 and scans, exposing the surface of the photosensitive drum 104 to the laser beam U.

[0210] Below the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K), an intermediate transfer unit 12 as a transfer member is provided. The intermediate transfer unit 12 includes a drive roller 12e, a steering roller 12c, and a tension roller 12b, and a flexible transfer belt 12a extends around these rollers.

[0211] The lower surface of the photosensitive drum 104 of each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) contacts the upper surface of the transfer belt 12a. The contact portion is the primary transfer portion. A primary transfer roller 12d is provided inside the transfer belt 12a so as to face the photosensitive drum 104.

[0212] The secondary transfer roller 6 is in contact with the steering roller 12c via the transfer belt 12a. The contact portion between the transfer belt 12a and the secondary transfer roller 6 is a secondary transfer portion.

[0213] The feeding unit 4 is provided below the intermediate transfer unit 12. The feeding unit 4 includes a sheet feeding roller 4b and a sheet feeding tray 4a on which the recording material S is loaded and accommodated.

[0214] The fixing device 7 and the paper discharge device 8 are arranged on Figure 2 On the upper left side of the image forming apparatus main assembly 170 in the image forming apparatus. The upper surface of the image forming apparatus main assembly 170 serves as the paper discharge tray 13.

[0215] The toner image is fixed on the recording material S by a fixing device provided in the fixing apparatus 7 , and the recording material is discharged to a paper discharge tray 13 .

[0216] [Imaging Operation]

[0217] The operation for forming a full-color image is as follows.

[0218] The photosensitive drum 104 of each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) is rotated at a predetermined speed (at a predetermined speed). Figure 3 The motor is driven to rotate in the direction of arrow A).

[0219] The transfer belt 12a is also in the forward direction ( Figure 2 The photosensitive drum 104 is rotationally driven in the same direction as the rotation of the photosensitive drum (in the direction of arrow C).

[0220] The laser scanner unit 14 is also driven. In synchronization with the driving of the laser scanner unit 14, the charging roller 105 uniformly charges the surface of the photosensitive drum 104 in each process cartridge to a predetermined polarity and potential. The laser scanner unit 14 scans and exposes the surface of each photosensitive drum 104 with a laser beam U according to the image signal of each color.

[0221] As a result, an electrostatic latent image corresponding to the image signal of the corresponding color is formed on the surface of each photosensitive drum 104. The formed electrostatic latent image is developed by the developing roller 106, which is driven to rotate at a predetermined speed. More specifically, the developing roller 106 contacts the photosensitive drum 104, and the toner moves from the developing roller 106 to the latent image on the photosensitive drum 104, causing the latent image to be developed into a toner image. In this embodiment, a contact development method is used, and the developing roller 106 and the photosensitive drum 104 are in contact with each other. However, a non-contact development method can also be used, in which the toner jumps from the developing roller 106 to the photosensitive drum 104 through the small gap between the developing roller 106 and the photosensitive drum 104.

[0222] Through the electrophotographic imaging process operation as described above, a yellow toner image corresponding to the yellow component of the full-color image is formed on the photosensitive drum 104 of the first process cartridge 100Y. Then, the toner image is primarily transferred onto the transfer belt 12a. A portion of the photosensitive drum 104 is exposed to the outside of the cartridge and contacts the transfer belt 12a. At this contact portion, the toner image on the surface of the photosensitive drum 104 is transferred onto the transfer belt 12a.

[0223] Similarly, a magenta toner image corresponding to the magenta component of the full-color image is formed on the photosensitive drum 104 of the second process cartridge 100M. Then, the toner image is superimposedly transferred onto the yellow toner image already transferred onto the transfer belt 12a.

[0224] Similarly, a cyan toner image corresponding to the cyan component of the full-color image is formed on the photosensitive drum 104 of the third process cartridge 100C. Then, the toner image is primarily transferred superimposedly onto the yellow and magenta toner images already transferred onto the transfer belt 12a.

[0225] Similarly, a black toner image corresponding to the black component of the full-color image is formed on the photosensitive drum 104 of the fourth process cartridge 100K. Then, the toner image is primarily transferred superimposedly onto the yellow, magenta, and cyan toner images already transferred onto the transfer belt 12a.

[0226] In this manner, a four-color full-color unfixed toner image of yellow, magenta, cyan, and black is formed on the transfer belt 12 a .

[0227] On the other hand, the recording materials S are separated and fed one by one at a predetermined control timing. The recording materials S are then introduced into a secondary transfer portion that is a contact portion between the secondary transfer roller 6 and the transfer belt 12a at a predetermined control timing.

[0228] Thus, the four-color superimposed toner images on the transfer belt 12 a are sequentially and collectively transferred onto the surface of the recording material S in the process of feeding the recording material S to the secondary transfer unit.

[0229] In more detail, the structure of the main assembly of the image forming apparatus will be described below.

[0230] [Overview of Process Cartridge Attachment / Removal Structure]

[0231] refer to Figure 42 and Figures 4 to 7 , the tray 171 supporting the process cartridge will be described in more detail. Figure 4 1 is a sectional view of the image forming apparatus M, in which the tray 171 is located inside the image forming apparatus main assembly 170 with the front door 11 opened. Figure 5 1 is a sectional view of the image forming apparatus M in a state where the tray 171 is located outside the image forming apparatus main assembly 170 , with the front door 11 open and the process cartridges 100 accommodated in the tray. Figure 6 1 is a sectional view of the image forming apparatus M in a state where the tray 171 is located outside the image forming apparatus main assembly 170 , with the front door 11 open and the process cartridge 100 having been removed from the tray. Figure 7 Part (a) is in Figure 4 A detailed partial view of the tray 171 as viewed from the drive side in the illustrated state. Figure 7 Part (b) is in Figure 4 A partial detailed view of the tray 171 viewed from the non-drive side in the state.

[0232] like Figure 4 and Figure 5 As shown, the tray 171 can move relative to the imaging device main assembly 170 in the arrow X1 direction (push direction) and the arrow X2 direction (pull direction). That is, the tray 171 is set to be retractable from the imaging device main assembly 170 and insertable into the imaging device main assembly 170, and the tray 171 is constructed to be movable in a substantially horizontal direction in a state where the imaging device main assembly 170 is installed on a horizontal floor. Here, the state where the tray 171 is located outside the imaging device main assembly 170 ( Figure 5 The state shown in FIG. 1 is referred to as the external position. In addition, the state in which the tray is placed inside the main assembly 170 of the imaging device with the front door 11 open and the photosensitive drum 104 and the transfer belt 12a separated from each other ( FIG. Figure 4 The state in ) is called the internal position.

[0233] In addition, the tray 171 has a mounting portion 171a, in which the process cartridge 100 can be mounted in an external position. Figure 6 Then, each process cartridge 100 mounted on the mounting portion 171a in an outer position of the tray 171 is supported by the tray 171 through the drive side cartridge cover member 116 and the immovable side cartridge cover member 117, as shown. Figure 7As shown. The process cartridge then moves within the imaging apparatus main assembly 170 as the tray 171 moves while being placed in the mounting portion 171a. During this movement, a gap is maintained between the transfer belt 12a and the photosensitive drum 104. The tray 171 can transport the process cartridge 100 into the imaging apparatus main assembly 170 without the photosensitive drum 104 contacting the transfer belt 12a (details will be described later).

[0234] As described above, by using the tray 171 , the plurality of process cartridges 100 can be collectively moved to a position inside the image forming apparatus main assembly 170 where an image can be formed, and collectively moved to the outside of the image forming apparatus main assembly 170 .

[0235] [Positioning of Process Cartridge Relative to Main Assembly of Electrophotographic Image Forming Apparatus]

[0236] refer to Figure 7 , the positioning of the process cartridge 100 relative to the image forming apparatus main assembly 170 will be described in more detail.

[0237] like Figure 7 As shown, the tray 171 is provided with positioning portions 171VR and 171VL for holding the cartridge 100. The positioning portions 171VR have straight portions 171VR1 and 171VR2, respectively. The center of the photosensitive drum is formed by Figure 7 The illustrated cover member 116 is defined by arcuate portions 116VR1 and 116VR2 contacting straight portions 171VR1 and 171VR2.

[0238] also, Figure 7 The tray 171 shown is provided with a rotation determining protrusion 171KR. Figure 7 The rotation determining recess 116KR of the cartridge cover member 116 shown cooperates to determine the posture of the process cartridge 100 relative to the apparatus main assembly.

[0239] The positioning portion 171VL and the rotation determining protrusion 171KL are provided at positions (non-driven side) that oppose each other across the intermediate transfer belt 12a in the longitudinal direction of the positioning portion 171VR and the process cartridge 100. That is, also on the non-driven side, the position of the process cartridge is determined by the engagement of the arcuate portions 117VL1 and 117VL2 of the cartridge cover member 117 with the positioning portion 171VL and the engagement of the rotation determining recess 117KL with the rotation determining protrusion 171KL.

[0240] By doing so, the position of the process cartridge 100 relative to the tray 171 is correctly determined.

[0241] Then, if Figure 5 As shown, the processing box 100 integrated with the tray 171 is moved in the direction of arrow X1 and inserted into Figure 5 Position shown.

[0242] Then, by closing the front door 11 in the direction of arrow R, the process cartridge 100 is pressed by a cartridge pressing mechanism (not shown) to be described later and fixed to the image forming apparatus main assembly 170 together with the tray 171. In addition, the transfer belt 12a is brought into contact with the photosensitive member 104 in association with the operation of the cartridge pressing mechanism. In this state, image formation can be performed ( Figure 2 ).

[0243] In the present embodiment, the positioning portion 171VR and the positioning portion 171V also function as reinforcements for maintaining rigidity in the pull-out operation of the tray 171 , and therefore, a metal plate is used, but the present invention is not limited thereto.

[0244] [Box pressing mechanism]

[0245] Next, refer to Figure 8 , the details of the box pressing mechanism will be described.

[0246] Figure 8 Part (a) shows only Figure 4 The process cartridge 100, the tray 171, the cartridge pressing mechanisms 190 and 191, and the intermediate transfer unit 12 in the state. Figure 8 Part (b) shows only Figure 2 The process cartridge 100, the tray 171, the cartridge pressing mechanisms 190 and 191, and the intermediate transfer unit 12 in the state.

[0247] The process cartridge 100 receives a driving force during the image forming process and further receives a driving force in the direction of arrow Z1 from the primary transfer roller 12d ( Figure 2 Therefore, in order to maintain a stable posture without a gap between the process cartridge and the positioning portions 171VR and 171VL during the image forming operation, it is necessary to press the process cartridge in the Z2 direction.

[0248] To achieve this, in this embodiment, the image forming apparatus main assembly 170 is provided with a cartridge pressing mechanism (190, 191).

[0249] As for the cartridge pressing mechanism (190, 191), the storage element pressing unit 190 is a non-driving side operation, and the cartridge pressing unit 191 is a driving side operation. This will be described in more detail below.

[0250] By closing Figure 4 The front door 11 shown, Figure 8 The storage element pressing unit 190 and the cartridge pressing unit 191 are shown descending in the direction of arrow Z2.

[0251] The storage element pressing unit 190 is provided with main assembly side electrical contacts (not shown) that primarily come into contact with electrical contacts of a storage element (not shown) provided in the process cartridge 100. By being interlocked with the front door 11 by a link mechanism (not shown), the storage element 140 and the electrical contacts on the main assembly side can be brought into and out of contact with each other.

[0252] That is, the contacts are brought into contact with each other by closing the front door 11 , and are separated by opening the front door 11 .

[0253] With this structure, when the processing box 100 moves together with the tray 171 inside the main assembly of the imaging device, the electrical contacts are not rubbed and the contacts are retracted from the insertion / removal trajectory of the processing box 100, thereby not hindering the insertion and removal operation of the tray 171.

[0254] The storage element pressing unit 190 also plays a role in pressing the process cartridge against the above-mentioned positioning portion 171VR.

[0255] Further, similar to the storage element pressing unit 190, the cartridge pressing unit 121 also descends in the direction of arrow Z2 in association with the operation of closing the front door 11, and plays a role in pressing the processing cartridge 100 against the above-mentioned positioning portion 171VL.

[0256] Furthermore, although the details will be described below, the cartridge pressing mechanism ( 190 , 191 ) also functions to press the urging members 152L and 152R of the process cartridge 100 downward, as will be described below.

[0257] [Drive transmission mechanism]

[0258] Next, refer to Figure 9 and Figure 10 (For better illustration, the tray 171 is omitted.) The drive transmission mechanism of the main assembly in this embodiment will be described.

[0259] Figure 9 Part (a) is where Figure 4 or Figure 5 A perspective view of the process cartridge 100 and the tray 171 is omitted in the state. Figure 9 B is a perspective view in which the process cartridge 100, the front door 11, and the tray 171 are omitted.

[0260] Figure 10 It is a side view of the process cartridge 100 as viewed from the driving side.

[0261] like Figure 10 As shown, the process cartridge in this embodiment includes a developing coupling portion 32a and a drum coupling (photosensitive member coupling) 143.

[0262] The structure is as follows: by closing the front door 11 ( Figure 9 , driving the processing box 100 and transmitting the driving force to the main component side drum drive coupling and the main component side developer drive coupling 185 of the processing box 100 protruding in the direction of arrow Y1 through a connecting rod mechanism (not shown).

[0263] In addition, by opening the front door 11 ( Figure 9 ), in the state of part (a), the drum drive coupling 180 and the developer drive coupling 185 are retracted in the direction of arrow Y2.

[0264] By retracting each coupling from the insertion / removal trajectory (X1 direction, X2 direction) of the process cartridge, insertion / removal of the tray 171 is not hindered.

[0265] By closing the front door 11 and starting to drive the main assembly of the imaging device, the above-mentioned drum drive coupling 180 is engaged with the drum coupling (coupling member, cartridge side coupling) 143. At the same time, the developer drive coupling 185 on the main assembly side is engaged with the developer coupling portion 32a. Therefore, the drive is transmitted to the process cartridge 100. The drive transmission to the process cartridge 100 is not limited to the above-mentioned structure, and a mechanism that only inputs the drive to the drum coupling and transmits the drive to the developer roller may be provided.

[0266] [Intermediate transfer unit structure]

[0267] Next, refer to Figure 9 , the intermediate transfer unit 12 of the image forming apparatus main assembly in this embodiment will be described.

[0268] In this embodiment, the structure is such that by closing the front door 11, the intermediate transfer unit 12 is raised in the direction of arrow R2 by a link mechanism (not shown) and moved to a position for image forming operation (the photosensitive drum 104 and the intermediate transfer belt 12a contact each other).

[0269] Furthermore, by opening the front door 11, the intermediate transfer unit 12 descends in the direction of the arrow R1, and the photosensitive drum 2 and the intermediate transfer belt 12a are separated from each other.

[0270] That is, in a state where the process cartridge 100 is set in the tray 171 , the photosensitive drum 104 and the intermediate transfer belt 12 a come into contact with and out of contact with each other according to the opening / closing operation of the front door 11 .

[0271] The structure is such that in the contact / separation operation, the intermediate transfer unit is Figure 4 The center point PV1 shown rises and falls while drawing a rotation trajectory.

[0272] The intermediate transfer belt 12a is driven by a force from a gear (not shown) coaxially arranged with the PV1. Therefore, by setting the position PV1 as the center of rotation, the intermediate transfer unit 12 can be raised and lowered without shifting the center of the gear. This eliminates the need to shift the center of the gear and allows the gear's position to be maintained with high precision.

[0273] With the above structure, when the processing box 100 is set in the tray 171, when the tray 11 is inserted or removed, the photosensitive drum 104 and the intermediate transfer belt 12a do not rub against each other, and thus, damage to the photosensitive drum 104 and image degradation caused by the charge storage device are prevented.

[0274] [Development separation control unit]

[0275] Next, refer to Figure 8 、 Figure 11 and Figure 12 , the separation mechanism of the main assembly of the image forming apparatus in this embodiment will be described.

[0276] Figure 11 100 is a sectional view of the image forming apparatus M taken along the driving side end of the process cartridge 100 . Figure 12 It is a perspective view of the development separation control unit viewed obliquely from above.

[0277] In this embodiment, the development separation control unit 195 controls the separation contact operation of the development unit 109 relative to the photosensitive drum 104 by engaging with a portion of the development unit 109. Figure 8 As shown, the developing separation control unit 195 is provided in a lower portion of the image forming apparatus main assembly 170 .

[0278] Specifically, the development separation control unit 195 is placed below the development input coupling portion 32 a and the drum coupling 143 in the vertical direction (downward in the arrow Z2 direction).

[0279] Furthermore, the developing separation control unit 195 is disposed in the longitudinal direction (Y1, Y2 direction) of the photosensitive drum 104 of the intermediate transfer belt 12. That is, the developing separation control unit 195 includes a driving side developing separation control unit 195R and a non-driving side developing separation control unit 195L.

[0280] By disposing the developing separation control unit 195 in the dead space of the image forming apparatus main assembly 170 as described above, the main assembly can be reduced in size.

[0281] The developing separation control unit 195R has four separation control members 196R corresponding to the process cartridges 100 (100Y, 100M, 100C, 100K), respectively. The four separation control members have substantially the same shape. The developing separation control unit 195R is always fixed to the main assembly of the imaging device. However, the separation control member 196R is constructed to be movable in the W41 and W42 directions by a control mechanism (not shown). The detailed structure will be described below.

[0282] The developer separation control unit 195L has four separation control members 196L corresponding to the process cartridges 100 (100Y, 100M, 100C, 100K). The four separation control members have substantially the same shape. The developer separation control unit 195L is always fixed to the main assembly of the imaging device. However, the separation control member 196L is constructed to be movable in the W41 and W42 directions by a control mechanism (not shown). The detailed structure will be described below.

[0283] Furthermore, in order for the development separation control unit 195 to engage with a portion of the development unit 109 and control the separation contact operation of the development unit 109 , a portion of the development control unit 196 and a portion of the development unit need to overlap in the vertical direction ( Z1 , Z2 directions).

[0284] Therefore, for overlapping in the vertical direction (Z1 and Z2 directions) as described above after the developing unit 109 of the process cartridge 100 is inserted in the X1 direction, a portion of the developing unit (in the case of this embodiment, the urging member 152) needs to protrude. Details will be described below.

[0285] In the case where the development separation control unit 195 itself is raised in the same manner as in the case of the intermediate transfer unit 12 for engagement, there are problems such as an increase in the operating force of the interlocked front door 11 and complication of a transmission system.

[0286] In this embodiment, a method is adopted in which the developer separation control unit 195 is fixed to the image forming apparatus main assembly 170, and a portion of the developer unit 109 (the urging member 152) protrudes downward (Z2) in the image forming apparatus main assembly 170, and one of the reasons for this arrangement is to solve this problem. In addition, the mechanism for causing the urging member 152 to protrude utilizes the mechanism of the above-mentioned storage element pressing unit 190 and the cartridge pressing unit, and therefore, the above-mentioned problem does not exist and the increase in the cost of the apparatus main assembly can be suppressed.

[0287] The entire unit of the developing separation control unit 195 is fixed to the image forming apparatus main assembly 170. However, as will be described below, a portion of the developing unit is movable so as to engage with the urging member 152 to cause an operation so that the developing unit 109 is in a separated state and a contact state relative to the photosensitive drum 104. The details will be described below.

[0288] [Overall structure of the process cartridge]

[0289] refer to Figure 3 、 Figure 13 and Figure 14 , the structure of the process cartridge will be described.

[0290] Figure 13 10 is an assembled perspective view of the process cartridge 100 viewed from the driving side, which is a side in the axial direction of the photosensitive drum 104 . Figure 14 1 is a perspective view of the process cartridge 100 as viewed from the driving side.

[0291] In this embodiment, the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) have the same electrophotographic process mechanism, but the colors of the contained toners and the filling amounts of the toners are different from each other.

[0292] The process cartridge 100 includes photosensitive drums 104 (4Y, 4M, 4C, 4K) and process devices acting on the photosensitive drums 104. The cartridge 100 includes a charging roller 105 as a process device, which is a charging device (charging member) for charging the photosensitive drums 104. In addition, the cartridge 100 includes a developing roller 106 as another process device, which is a developing device (developing member) for developing the latent image formed on the photosensitive drum 104.

[0293] In addition, as an example of the processing means, a cleaning means (eg, a cleaning blade) for removing residual toner remaining on the surface of the photosensitive drum 104 can be considered. However, the image forming apparatus of this embodiment adopts a structure in which no cleaning means contacting the photosensitive drum 104 is provided.

[0294] The process cartridge 100 is divided into a drum holding unit 108 (108Y, 108M, 108C, 108K) and a developing unit 109 (109Y, 109M, 109C, 109K).

[0295] [Drum holding unit structure]

[0296] like Figure 3 and Figure 13As shown, the drum holding unit 108 includes a photosensitive drum 104, a charging roller 105, and a drum frame 115 as a first frame. The photosensitive drum 104 is combined with a coupling 143 and a drum flange 142 to provide a drum unit 103 (see FIG. Figure 1 Part (a), details will be described below).

[0297] The drum unit 103 is rotatably supported by a driving side cover member 116 and a non-driving side cover member 117 provided at opposite ends in the longitudinal direction of the process cartridge 100. The driving side cover member 116 and the non-driving side cover member 117 will be described below.

[0298] In addition, if Figure 13 and Figure 14 As shown, a drum coupling 143 for transmitting driving force to the photosensitive drum 104 is provided near one end in the longitudinal direction of the photosensitive drum 104. As described above, the coupling 143 is connected to the main assembly side drum drive coupling 180 (see FIG. 1 ) as the drum drive output unit of the main assembly 170 of the imaging device. Figure 9 ) is engaged. The driving force of the driving motor (not shown) of the image forming apparatus main assembly 170 is transmitted to the photosensitive drum 104 to rotate it in the direction of arrow A. Furthermore, the photosensitive drum 104 is provided with a drum flange 142 near the other end (second end portion) in the longitudinal direction.

[0299] The shaft portion 143j of the coupling 143 (see Figure 1 ) is supported by the drive side cartridge cover 116, and the drum flange 142 is supported by a shaft fixed to the non-drive side cartridge cover 117. Thus, the drum unit 103 is rotatably supported in the cartridge. That is, the end of the photosensitive drum 104 is rotatably supported by the end of the cartridge housing (i.e., the cartridge covers 116 and 117) via the coupling 143 and the drum flange 142.

[0300] The charging roller 105 is supported by the drum frame 115 in such a manner as to be in contact with the photosensitive drum 104 so that it can be rotationally driven by the photosensitive drum 104 .

[0301] Of the opposite sides of the drum unit 103 in the longitudinal direction (axial direction), the side on which the coupling 143 is provided is the drive side, and the side on which the drum flange 142 is placed is the non-drive side. That is, of the opposite ends of the photosensitive drum 104 in the axial direction, the coupling 143 is fixed near the end on the drive side, and the drum flange 142 is fixed near the end on the side opposite to the drive side. Of the opposite ends of the photosensitive drum 104, one can be referred to as a first end, and the other can be referred to as a second end. Figure 80 An end portion 104 a on the drum driving side and an end portion 104 b on the non-driving side of the photosensitive drum are shown.

[0302] Similar to the drum unit 103, among the opposite sides of the cartridge 100, the side on which the coupling 143 is placed is referred to as the drive side, and the side opposite to the drive side is referred to as the non-drive side. For example, Figure 10 and Figure 19 is a diagram showing the drive side of the cartridge. Figure 16 is a diagram showing the non-driving side of the cartridge.

[0303] like Figure 13 and Figure 14 As shown, the drive side cover 116 is a component provided at the drive side end of the housing of the cassette 100, and the non-drive side cover is a component provided at the non-drive side end of the housing. The drum coupling 143 supported by the drive side cover 116 can be considered to be located near the non-drive side end of the housing of the cassette 100. Of the opposite ends of the cassette 100, one can be referred to as a first end, and the other can be referred to as a second end.

[0304] [Developer unit structure]

[0305] like Figure 3 and Figure 13 As shown, the developing unit 109 includes a developing roller 106, a toner feeding roller (toner supply roller) 107, a developing blade 130, a developing unit frame 125, etc. The developing unit frame 125 includes a lower frame 125a and a cover member 125b. The lower frame 125a and the cover member 125b are connected by ultrasonic welding or the like.

[0306] The developing frame 125 as a second frame (second housing) includes a toner accommodating portion 129 for accommodating toner to be supplied to the developing roller 106. In addition, the developing frame 125 rotatably supports the developing roller 106 and the toner feeding roller 107 by means of a driving side bearing 126 and a non-driving side bearing 127, which will be described later, and holds a developing blade 130 for regulating the layer thickness of the toner on the circumferential surface of the developing roller 106.

[0307] The development blade 130 is formed by attaching an elastic member 130b, which is a sheet of metal with a thickness of approximately 0.1 mm, to a support member 130a, which is a metal material with an L-shaped cross-section, by welding or similar means. The development blade 130 is attached to the development frame 125 at two locations using fixing screws 130c: one near one end in the longitudinal direction and another near the other end. The development roller 106 includes a core metal 106c and a rubber portion 106d.

[0308] The developing roller 106 is rotatably supported by a drive-side bearing 126 and a non-drive-side bearing 127, which are respectively mounted on opposite ends of the developing frame 125 in the longitudinal direction. The developing frame 125, the drive-side bearing 126, and the non-drive-side bearing 127 are part of the frame (housing) of the cartridge. In a broad sense, the bearings 126 and 127 can be regarded as part of the developing frame 125, and the bearings 126 and 127 and the developing frame 125 can be collectively referred to as the developing frame.

[0309] The toner feeding roller 107 conveys and supplies the toner contained in the toner containing portion 129 to the developing roller 106 to develop the latent image on the photosensitive drum 104. The toner feeding roller 107 is in contact with the developing roller 106.

[0310] In addition, if Figure 13 and Figure 14 As shown, a developing input coupling portion (developing coupling) 32a for transmitting a driving force to the developing unit 109 is provided on one side in the longitudinal direction of the developing unit 109. The developing input coupling portion 32a is connected to a developing drive coupling 185 (see FIG. 1 ) on the main assembly side as a developing drive output portion of the image forming apparatus main assembly 170. Figure 9 ) is engaged, and the driving force of the driving motor (not shown) of the imaging device main assembly 170 is input to the developing unit 109.

[0311] The driving force input to the developing unit 109 is transmitted by a transmission system (not shown) provided in the developing unit 109 so that the developing roller 106 can be Figure 3 1. Similarly, the driving force received by the development input coupling portion 32a also rotates the toner feed roller 107 to supply toner to the development roller 106.

[0312] On one side in the longitudinal direction of the developing unit 109, a developing cover member 128 is provided that supports and covers the developing input coupling portion 32a and the transmission system (not shown). The outer diameter of the developing roller 106 is selected to be smaller than the outer diameter of the photosensitive drum 104. The outer diameter of the photosensitive drum 104 of this embodiment is selected to be within the range of Φ18 to Φ22 (mm), and the outer diameter of the developing roller 106 is selected to be within the range of Φ8 to Φ14. By selecting such outer diameters, an efficient arrangement can be achieved.

[0313] [Assembly of the drum holding unit and the developing unit]

[0314] refer to Figure 13 , the assembly of the drum holding unit 108 and the developing unit 109 will be described. The drum holding unit 108 and the developing unit 109 are connected by the driving side cartridge cover member 116 and the non-driving side cartridge cover member 117 provided at the respective ends in the longitudinal direction of the process cartridge 100.

[0315] The driving side cover member 116 provided on one side (driving side) of the process cartridge 100 in the longitudinal direction is provided with a developing unit supporting hole 116a for supporting the developing unit in a swingable (movable) manner. Similarly, the non-driving side cover member 117 provided on the other side (non-driving side) of the process cartridge 100 in the longitudinal direction is provided with a developing unit supporting hole 117a for swingably supporting the developing unit 109.

[0316] In addition, the driving side cartridge cover member 116 and the non-driving side cartridge cover member 117 are provided with drum support holes 116b and 117b for rotatably supporting the photosensitive drum 104. Here, on the driving side, the outer diameter portion of the cylindrical portion 128b of the developing cover member 128 is fitted into the developing unit support hole 116a of the driving side cartridge cover member 116. On the non-driving side, the outer diameter portion of the cylindrical portion (not shown) of the non-driving side bearing 127 is fitted into the developing unit support hole 117a of the non-driving side cartridge cover member 117.

[0317] In addition, the opposite ends in the longitudinal direction of photosensitive drum 104 are respectively assembled into the drum supporting hole 116b of drive side box cover member 116 and the drum supporting hole 117b of non-drive side box cover member 117. Then, drive side box cover member 116 and non-drive side box cover member are fixed to the drum frame 115 of drum holding unit 108 with screws or adhesive (not shown).Thus, developing unit 109 is rotatably supported by drive side box cover member 116 and non-drive side box cover member 117.Developing unit 109 can move (rotate) relative to drum holding unit 108, and developing roller 106 can move relative to photosensitive drum by this movement.When imaging, developing roller 106 can be placed on the position acting on the photosensitive drum 104.

[0318] The drum frame 115 and the cover members 116 and 117 are part of the cartridge frame (housing). More specifically, they are the frame of the drum holding unit 108. In addition, since the cover members 116 and 117 are respectively fixed to one end and the other end of the drum frame 115, the cover members 116 and 117 can be regarded as part of the drum frame 115. Alternatively, the cover members 116 and 117 and the drum frame 115 can be collectively referred to as the drum frame.

[0319] Furthermore, one of the frame (115, 116, 117) of the drum holding unit 108 and the frame (125, 126, 127) of the developing unit may be referred to as a first frame (first housing), and the other may be referred to as a second frame (second housing), etc. Furthermore, the frame (115, 116, 117) of the drum holding unit 108 and the frame (125, 126, 127) of the developing unit may be collectively referred to as a frame of the cartridge (cassette housing) without any particular distinction therebetween.

[0320] Figure 14 A state is shown in which the drum holding unit 108 and the developing unit 109 are assembled through the above-described steps to provide the entire process cartridge 100 .

[0321] The axis connecting the center of the developing unit support hole 116a of the driving side cartridge cover member 116 and the center of the developing unit support hole 117a of the non-moving side cartridge cover member 117 is referred to as the swing axis K. Here, the cylindrical portion 128b of the developing cover member 128 on the driving side is coaxial with the developing input coupling 74. That is, the developing unit 109 has a structure that transmits the driving force from the image forming apparatus main assembly 170 on the swing axis K. In addition, the developing unit 109 is rotatably supported around the swing axis K.

[0322] [Structure of separation / contact mechanism]

[0323] The structure of the photosensitive drum 104 of the process cartridge 100 and the developing roller 106 of the developing unit 109 separating and contacting each other in this embodiment will be described in detail. The process cartridge includes a separation contact mechanism 150R on the driving side and a separation contact mechanism 150L on the non-driving side. Figure 15 An assembled perspective view showing the driving side of the developing unit 109 including the separation contact mechanism 150R. Figure 16 An assembled perspective view of a developing unit including the separating contact mechanism 150L on the non-driving side is shown. Regarding the separating contact mechanism, details of the separating contact mechanism 150R on the driving side will be described first, and then the separating contact mechanism 150L on the non-driving side will be described.

[0324] Since the separating contact mechanisms on the drive side and the non-drive side have almost the same function, the same reference numerals are used on both sides, except that R is added at the end for the drive side and L is added for the non-drive side.

[0325] The separation contact mechanism 150R includes a separation holding member 151R as a restriction member, an urging member 152R as a pressing member, and a tension spring 153 .

[0326] The separation contact mechanism 150L includes a separation holding member 151L as a restriction member, an urging member 152L as a pressing member, and a tension spring 153 .

[0327] [Detailed Description of Separation and Holding Member R]

[0328] refer to Figure 17 , the separation holding member 151R will be described in detail.

[0329] Figure 17 Part (a) is a front view of the separation holding member 151R itself of the process cartridge 100 as viewed from the driving side longitudinal direction. Figure 17Parts (b) and (c) are perspective views of the separation holding member 151R itself. Figure 17 Part (d) is in Figure 17 : A view of the separation holding member 151R as viewed in the direction of arrow Z2 in part (a) (vertically upward in the imaging state). The separation holding member 151R includes an annular support receiving portion 151Ra and includes a separation holding portion 151Rb protruding from the support receiving portion 151Ra in a radial direction of the support receiving portion 151Ra. The free end of the separation holding portion 151Rb has an arc-shaped separation holding surface 151Rc, which has a center on the separation holding member swing axis H and is inclined at an angle θ1 relative to a line HA parallel to the separation holding member swing axis H. The angle θ1 is selected to satisfy equation (1).

[0330] 0°≦θ1≦45°...(1)

[0331] Furthermore, the separation holding member 151R has a second regulated surface 151Rk adjacent to the separation holding surface 151Rc. Furthermore, the separation holding member 151R is provided with a second pressed portion 151Rd protruding beyond the support receiving portion 151Ra in Z2, and an arcuate second pressed surface 151Re protruding from the second pressed portion 151Rd in the direction of the separation holding member swing axis H of the support receiving portion 151Ra.

[0332] Furthermore, the separation holding member 151R includes a main body portion 151Rf connected to the support receiving portion 151Ra, and the main body portion 151Rf is provided with a spring hook portion 151Rg protruding in the direction of the separation holding member swing axis H of the support receiving portion 151Ra. Furthermore, the main body portion 151Rf is provided with a rotation (on its own axis) preventing portion 151Rm protruding in the Z2 direction, and a rotation preventing surface 151Rn is provided in a direction facing the second pressure receiving surface 151Re.

[0333] [Detailed description of the force applying member R]

[0334] refer to Figure 18 , the urging member 152R will be described in detail.

[0335] Figure 18 Part (a) is a front view of the urging member 152R itself as viewed from the longitudinal direction of the process cartridge 100, and Figure 18 B and Figure 18 C is a perspective view of the urging member 152R itself.

[0336] The urging member 152R is provided with an elliptical support receiving portion 152Ra having an elliptical shape. Here, the longitudinal direction of the ellipse of the elliptical support receiving portion 152Ra is indicated by an arrow LH, the upward direction is indicated by an arrow LH1, and the downward direction is indicated by an arrow LH2. In addition, the direction in which the elliptical support receiving portion 152Ra is formed is indicated by HB. The urging member 152R has a protruding portion 152Rh formed on the downstream side of the elliptical support receiving portion 152Ra in the direction of the arrow LH2. The elliptical support receiving portion 152Ra and the protruding portion 152Rh are connected by a main body portion 152Rb. On the other hand, the urging member 152R includes a pressed portion 152Re protruding in the direction of the arrow LH1 and substantially perpendicular to the direction of the arrow LH1, and has an arc-shaped pressed surface 152Rf on the downstream side in the direction of the arrow LH1, and has a push limiting surface 152Rg on the upstream side. Furthermore, the urging member 152R has a first accommodation restriction surface 152Rv extending from the main body portion 152Rb on the upstream side in the arrow LH2 direction, and a second accommodation restriction surface 152Rw adjacent to the first accommodation restriction surface 152Rv and substantially parallel to the first pressing surface 152Rq.

[0337] The protruding portion 152Rh includes a first force receiving portion 152Rk and a second force receiving portion 152Rn, which are arranged to face each other in a direction substantially perpendicular to the direction of arrow LH2 at their ends in the direction of arrow LH2. The first force receiving portion 152Rk and the second force receiving portion 152Rn respectively have a first force receiving surface 152Rm and a second force receiving surface 152Rp extending in the HB direction and having an arcuate shape. Furthermore, the protruding portion 152Rh has a locking portion 152Rt and a spring hook portion 152Rs protruding in the HL direction. The locking portion 152Rt has a locking surface 152Ru facing the same direction as the first force receiving surface 152Rp.

[0338] Furthermore, the urging member 152R is a part of the main body portion 152Rb and is arranged on the upstream side of the second force receiving portion 152Rn in the direction of the arrow LH2, and has a first pressing surface 152Rq facing the same direction as the second force receiving surface 152Rp. Furthermore, the urging member 152R has a second pressing surface 152Rr that is perpendicular to the first accommodation restricting surface 152Rv and is opposed to the first pressing surface 152Rq.

[0339] When the process cartridge 100 is mounted on the image forming apparatus main assembly 170 , the LH1 direction is substantially the same as the Z1 direction, and the LH2 direction is substantially the same as the Z2 direction.

[0340] [Assembly of separation / contact mechanism R]

[0341] Next, refer to Figure 10 and Figures 15 to 19 , the assembly of the separation contact mechanism will be described. Figure 19 151R is a perspective view of the process cartridge 100 as viewed from the driving side after the process cartridge 100 is assembled with the separation holding member 151R.

[0342] As mentioned above Figure 15 As shown, in the developing unit 109, the outer diameter portion of the cylindrical portion 128b of the developing cover member 128 is fitted into the developing unit supporting hole portion 116a of the driving side cartridge cover member 116. Thus, the developing unit 109 is rotatably supported about the swing axis K relative to the photosensitive drum 104. In addition, the developing cover member 128 includes a cylindrical first supporting portion 128c and a second supporting portion 128k that protrude in the direction of the swing axis K.

[0343] The outer diameter of the first support portion 128c is matched with the inner diameter of the support receiving portion 151Ra of the separation holding member 151R to rotatably support the separation holding member 151R. Here, the swing center of the separation holding member 151R assembled to the development cover member 128 is the separation holding member swing axis H. The development cover member includes a first holding portion 128d protruding in the direction of the separation holding member swing axis H. Figure 15 As shown, the movement of the separation holding member 151R assembled to the development cover member 128 in the direction of the swing axis H is restricted by the abutment of the first holding portion 128 d with the separation holding member 151R.

[0344] In addition, the outer diameter of the second support portion 128k cooperates with the inner wall of the elliptical support receiving portion 152Ra of the urging member 152R to support the urging member 152R so as to be rotatable and movable in the elliptical direction. Here, the swing center of the urging member 152R assembled to the development cover member 128 is the urging member swing axis HC. Figure 15 As shown, the movement of the urging member 152R assembled to the development cover member 128 in the direction of the swing axis HC is restricted by the abutment of the second retaining portion 128 m with the separation retaining member 151R.

[0345] Figure 101 is a sectional view taken along line CS, in which a portion of the drive-side cartridge cover member 116 and a portion of the developer cover member 128 are omitted so that a fitting portion between the elliptical support receiving portion 151Ra of the urging member 152R and the cylindrical portion 128b of the developer cover member 128 can be seen. The separation contact mechanism 150R is provided with a tension spring 153 as an urging means for urging the separation holding member 151R to rotate about the separation holding member swing axis H in the direction of arrow B1 in the figure and for urging the urging member 152R in the direction of arrow B3.

[0346] The arrow B3 direction is aligned with the elliptical direction LH2 (see FIG. Figure 18 ) is substantially parallel to the direction. The tension spring 153 is assembled between the spring hook portion 151Rg provided on the separation holding member 151R and the spring hook portion 152Rs provided on the urging member 152R. The tension spring 153 is Figure 10 The tension spring 153 applies a force in the direction of arrow F2 to the spring hook portion 151Rg of the separation holding member 151R, thereby applying an urging force for rotating the separation holding member 151R in the direction of arrow B1. In addition, the tension spring 153 applies a force in the direction of arrow F1 to the spring hook portion 152Rs of the urging member 152R, thereby applying an urging force for moving the urging member 152R in the direction of arrow B3.

[0347] The line connecting the spring hook portion 151Rg of the separation retaining member 151R and the spring hook portion 152Rs of the force retaining member 152R is GS. The line connecting the spring hook portion 152Rs of the force applying member 152R and the force applying member swing axis HC is HS. Here, the angle θ2 formed by the lines GS and HS is selected to satisfy the following equation (2), where the clockwise direction around the spring hook portion 152Rs of the force applying member 152R is positive. As a result, the force applying member 152R is urged to rotate in the direction of arrow BA about the force applying member swing axis HC.

[0348] 0°≦θ2≦90°...(2)

[0349] like Figure 15 As shown, in the developing drive input gear 132, the inner diameter portion of the cylindrical portion 128b of the developing cover member 128 and the outer diameter portion of the cylindrical portion 32b of the developing drive input gear 132 are engaged, and further, the supporting portion 126a of the driving side bearing 126 and the cylindrical portion (not shown) of the developing drive input gear are engaged. Thus, the driving force can be transmitted to the developing roller gear 131, the toner feeding roller gear 133, and other gears.

[0350] In this embodiment, the mounting positions of the separation holding member 151R and the urging member 152R are as follows. Figure 15 As shown, in the direction of the swing axis K, the separation and holding member 151R is provided on the side (outer side in the longitudinal direction) where the drive side cartridge cover member 116 is provided, with the developer cover member 128 interposed therebetween. The force member 152R is provided on the side (inner side in the longitudinal direction) where the developer drive input gear 13 is provided. However, the positions thereof are not limited thereto, and the positions of the separation and holding member 151R and the force member 152R may be interchanged, and the separation and holding member 151R and the force member 152R may be provided on one side in the direction of the swing axis K relative to the developer cover member 128. In addition, the arrangement order of the separation and holding member 151R and the force member 152R may be interchanged.

[0351] The developing cover member 128 is fixed to the developing frame 125 via the driving side bearing 126 to form the developing unit 109. Figure 15 As shown, the fixing method in this embodiment uses fixing screws 145 and an adhesive (not shown), but the fixing method is not limited to this example, and for example, welding such as welding by heating or pouring and hardening a resin material may be used.

[0352] here, Figure 20 is a cross-sectional view, wherein, for ease of explanation, Figure 10 The periphery of the separation holding portion 151R in the drawing is enlarged and a portion of the tension spring 153 and the separation holding member 151R are partially omitted by the partial section line CS4. In the force member 152R, the first limiting surface 152Rv of the force member 152R contacts the first limiting surface 128h of the developer cover member 128 by the urging force of the tension spring 153 in the F1 direction in the figure, as described above. In addition, the second limiting surface 152Rw of the force member 152R contacts the second limiting surface 128q of the developer cover member 128 and is thereby positioned. This position is referred to as the accommodation position (reference position) of the force member 152R. In addition, the separation holding member 151R rotates in the B1 direction around the swing axis H of the separation holding member by the urging force of the tension spring 153 in the F2 direction, and the second pressed portion 151Rd of the separation holding member 151R contacts the second pressing surface 152Rr of the force member 152R, thereby stopping the rotation. This position is referred to as the separation holding position (limiting position) of the separation holding member 151R.

[0353] also, Figure 21 Here is a diagram, where, for ease of explanation, Figure 10The periphery of the separation holding portion 151R in the embodiment is enlarged and the tension spring 153 is omitted. Here, consider the case where the process cartridge 100 including the separation contact mechanism 150R according to the present embodiment is transported. Figure 21 In the event of a fall in the JA direction of the separation holding member 151R. At this time, the separation holding member 151R receives a force that rotates it in the direction of arrow B2 by its own weight around the separation holding swing axis H. Therefore, when the rotation in the B2 direction starts, the rotation preventing surface 151Rn of the separation holding member 151R contacts the locking surface 152Ru of the force applying member 152R, and the separation holding member 151R receives a force in the F3 direction in the figure to suppress the rotation in the B2 direction. Thus, the separation holding member 151R can be prevented from rotating in the B2 direction during transportation, and the separation state between the photosensitive drum 104 and the developing unit 109 can be prevented from being damaged.

[0354] In this embodiment, the tension spring 153 is mentioned as the urging means for urging the separation and holding member 151R to the separation and holding position and for urging the biasing member 152R to the accommodation position, but the urging means is not limited to this example. For example, a torsion coil spring, a leaf spring, or the like can be used as the urging means for urging the biasing member 152R to the accommodation position and the separation and holding member 151R to the separation and holding position. Furthermore, the urging means can be made of a material that is elastic and can urge the separation and holding member 151R and the biasing member 152R, such as a mold.

[0355] As described above, the developing unit 109 provided with the separating contact mechanism 150R is integrally coupled to the drum holding unit 108 via the driving side cartridge cover member 116 as described above ( Figure 19 status in ).

[0356] Figure 22 is Figure 19 A view as seen in the direction of arrow J in part (a). Figure 15 As shown, the driving side cover 116 of this embodiment has a contact surface 116c. Figure 22 As shown, the contact surface 116c is inclined at an inclination angle θ3 relative to the swing axis K. It is desirable that the angle θ3 is the same as the angle θ1 forming the separation holding surface 151Rc of the separation holding member 151R, but the angle θ3 is not limited to this example. Figure 15 and Figure 19As shown, when the drive side cartridge cover member 116 is assembled to the developing unit 109 and the drum holding unit 108, the contact surface 116c faces the separation holding surface 151Rc of the separation holding member 151R placed at the separation holding position. The contact surface 116c is brought into contact with the separation holding surface 151Rc by the urging force of the developing pressure spring 134 described below. The structure is such that when the engaging surface 116Rc and the separation holding surface 151Rc are brought into contact with each other, the posture of the developing unit 109 is positioned so that the developing roller 106 of the developing unit 109 and the photosensitive drum 104 are separated by a gap P1. The state in which the developing roller 106 (developing member) is separated from the photosensitive drum 104 by the separation holding member 151R is referred to as the separation position (retracted position) of the developing unit 109 (see Figure 42 part (a)).

[0357] Here, reference Figure 42 , the separation state and the contact state of the process cartridge 100 will be described in detail.

[0358] Figure 42 17 is a side view of the process cartridge 100 as viewed from the driving side, wherein the process cartridge 100 is mounted inside the image forming apparatus main assembly 170. Figure 42 Part (a) shows a state in which the developing unit 109 is separated from the photosensitive drum 104. Figure 42 Part (b) shows a state in which the developing unit 109 is in contact with the photosensitive drum 104.

[0359] First, with the separation-holding member 151R positioned in the separation-holding position and the developing unit 109 in the separation position, the pressed portion 152Re of the urging member 152R is pushed in the ZA direction. Consequently, the protruding portion 152Rh of the urging member 152R protrudes from the process cartridge 100. The second pressed surface 151Re of the separation-holding member 151R contacts the second pressing surface 152Rr of the urging member 152R via the tension spring 153 as described above. Therefore, when the second force receiving portion 152Rn is pressed in the direction of arrow W42, the urging member 152R rotates about the urging member swing axis HC in the direction of arrow BB, causing the separation-holding member 151R to rotate in the direction of arrow B2. When the separation-holding member 151R rotates in the direction of arrow B2, the separation-holding surface 151Rc separates from the contact surface 116c, allowing the developing unit 109 to rotate about the swing axis K in the direction of arrow V2 from the separation position. That is, the developing unit 109 rotates in the V2 direction from the separated position, and the developing roller 106 of the developing unit 109 contacts the photosensitive drum 104. Here, the position of the developing unit 109 where the developing roller 106 and the photosensitive drum 104 contact each other is referred to as a contact position (developing position) ( Figure 4216. The state of part (b)). The position in which the separation holding surface 151Rc of the separation holding member 151R is separated from the contact surface 116c is referred to as a separation allowing position (allowing position). When the developing unit 109 is located at the contact position, the second limiting surface 151Rk of the separation holding member 151R contacts the second limiting surface 116d of the driving side cartridge cover 116, so that the separation holding member 151R is maintained at the separation releasing position.

[0360] Furthermore, the driving side bearing 126 has a first pressure receiving surface 126 c which is a surface perpendicular to the swing axis K. Since the driving side bearing 126 is fixed to the developing unit 109, the developing unit 109 presses the first force receiving portion 152Rk of the force applying member 152R in the direction of the arrow 41 in a state where the developing unit is in the contact position. Then, by the first pressing surface 152Rq coming into contact with the first pressure receiving surface 126 c, the developing unit 109 rotates in the direction of the arrow V1 about the swing axis K to move to the separated position ( Figure 42 Here, the direction in which the first force receiving surface 126c moves when the developing unit 109 moves from the contact position to the separation position is represented by Figure 42 Part (a) and Figure 42 , as shown by arrow W41 in part (b) of FIG. In addition, the direction opposite to arrow W41 is depicted by arrow W42, and the direction of arrow W41 and the direction of arrow W42 are substantially horizontal (X1, X2 directions). The second force receiving surface 152Rp of the force applying member 152R assembled to the developing unit 109 as described above is located on the upstream side of the first force receiving surface 126c of the driving side bearing 126 in the direction of arrow W41. In addition, the first force receiving surface 126c and the second force receiving surface 151Re of the separation retaining member 151R are arranged at a position where they at least partially overlap in the W1 and W2 directions.

[0361] The operation of the separating contact mechanism 150R in the image forming apparatus main assembly 170 will be described in detail below.

[0362] [Installing the process cartridge into the imaging device main assembly]

[0363] Next, we will refer to Figure 12 、 Figure 23 and Figure 24 Description will be made of the engagement operation between the separation contact mechanism 150R of the process cartridge 100 and the development separation control unit 195 of the image forming apparatus main assembly 170 when the process cartridge 100 is mounted to the image forming apparatus main assembly 170. For ease of explanation, these figures are sectional views in which a portion of the development cover member 128 and a portion of the drive side cartridge cover member 116 are omitted along partial sectional lines CS1 and CS2, respectively.

[0364] Figure 23 1 is a view seen from the driving side of the process cartridge 100 when the process cartridge 100 is mounted on the cartridge tray 171 (not shown) of the image forming apparatus M and the cartridge tray 171 is inserted into the first mounting position. In this figure, illustration is omitted except for the process cartridge 100, the cartridge pressing unit 121, and the separation control member 196R.

[0365] As described above, the imaging device main assembly 170 of this embodiment includes a separation control member 196R corresponding to each process cartridge 100 as described above. When the process cartridge 100 is placed in the first inner position and the second inner position, the separation control member 196R is arranged on the lower side of the imaging device main assembly 170 below the separation retaining member 151R. The separation control member 196R has a first force application surface 196Ra and a second force application surface 196Rb that protrude toward the process cartridge 100 and face each other across a space 196Rd. The first force application surface 196Ra and the second force application surface 196Rb are connected to each other by a connecting portion 196Rc in the lower side of the imaging device main assembly 170. In addition, the separation control member 196R is rotatably supported by the control metal plate 197 around the rotation center 196Re. The separation member 196R is normally urged in the E1 direction by an urging spring. Furthermore, the control metal plate 197 is configured to be movable in the W41 and W42 directions by a control mechanism (not shown), so that the separation control member 196R is configured to be movable in the W41 and W42 directions.

[0366] As described above, in association with the transition of the front door 11 of the image forming apparatus main assembly 170 from the open state to the closed state, the cartridge pressing unit 121 is lowered in the direction of the arrow ZA, and the first force applying portion 121a comes into contact with the pressed surface 152Rf of the force applying member 152R. Thereafter, when the cartridge pressing unit 121 is lowered to a predetermined position as the second mounting position, the protruding portion 152Rh of the force applying member 152R protrudes downward in the Z2 direction of the process cartridge 100 ( Figure 24 This position is referred to as the protruding position of the urging member 152R. When this operation is completed, as shown in FIG. Figure 24As shown, a gap T4 is formed between the first force-applying surface 196Ra of the separation control member 196R and the first force-receiving surface 152Rp of the force-applying member 152R, and a gap T3 is formed between the second force-applying surface 196Rb and the second force-receiving surface 152Rp. The separation control member 196R is then placed in a second mounting position where it does not act on the force-applying member 152R. This position of the separation control member 196R is referred to as the home position. At this point, the arrangement is such that the first force-receiving surface 152Rp of the force-applying member 152R and the first force-applying surface 196Ra of the separation control member 196R partially overlap in the W1 and W2 directions. Similarly, the arrangement is such that the second force-receiving surface 152Rp of the force-applying member 152R and the second force-applying surface 196Rb of the separation control member 196R partially overlap in the W1 and W2 directions.

[0367] [Contact Operation of Developing Unit]

[0368] Next, refer to Figures 24 to 26 , the contact operation between the photosensitive drum 104 and the developing roller 106 by the separating contact mechanism 150R will be described in detail. For convenience of explanation, these figures are cross-sectional views of a portion of the developing cover member 128, a portion of the driving side cartridge cover member 116, and a portion of the driving side bearing 126 taken along lines CS1, CS2, and CS3, respectively.

[0369] In the structure of this embodiment, the developing input coupling 32 is Figure 24 The developing roller 106 is rotated by receiving a driving force in the direction of the arrow V2 from the main assembly 170 of the image forming apparatus. That is, the developing unit 109 including the developing input coupling 32 receives a torque in the direction of the arrow V2 about the swing axis K from the main assembly 170 of the image forming apparatus. Figure 24 As shown in FIG. 1 , when the developing unit 109 is in the separated position and the separation holding member 151R is in the separated holding position, the developing unit 109 receives the torque and the urging force by the developing pressure spring 134, as will be described later. Even in this case, the separation holding surface 151Rc of the separation holding member 151R contacts the contact surface 116c of the drive side cartridge cover member 116, and therefore, the posture of the developing unit 109 is maintained at the separated position.

[0370] The separation control member 196R of this embodiment is configured to be Figure 24Moves from the original position in the direction of the middle arrow W42. When the separation control member 196R moves in the W42 direction, the second force applying surface 196Rb of the separation control member 196R and the second force receiving surface 152Rp of the force applying member 152R contact each other, so that the force applying member 152R rotates in the BB direction around the swing axis HC of the force applying member 152R. In addition, as the force applying member 152R rotates further, the separation holding member 151R rotates in the B2 direction, and at the same time, the second pressing surface 152Rr of the force applying member 152R contacts the second pressure receiving surface 151Re of the separation holding member 151R. Then, the separation holding member 151R is rotated to the separation allowing position where the separation holding surface 151Rc and the contact surface 116c are separated from each other by the force applying member 152R. Here, the separation holding member 151R is used to move Figure 25 The position of the separation control member 196R of the separation allowing position shown is referred to as a first position.

[0371] In this manner, the separation control member 196R moves the separation holding member 151R to the separation allowing position. Then, the developing unit 109 rotates in the V2 direction by the torque received from the image forming apparatus main assembly 170 and the developing pressure spring 134 to be described later, and moves to the point where the developing roller 106 and the photosensitive drum 104 come into contact with each other ( Figure 25 At this time, the separation holding member 151R, which is pushed in the direction of arrow B1 by the tension spring 153, is maintained at the separation allowing position by the second regulated surface 151Rk being in contact with the second limiting surface 116d of the drive side box cover member 116. Thereafter, the separation control member 196R moves in the direction of W41 and returns to the original position. At this time, the force applying member 152R is rotated in the BA direction by the tension spring 153, and the first pressing surface 152Rq of the force applying member 152R and the first pressing surface 126c of the drive side bearing 126 come into contact with each other ( Figure 26 status shown).

[0372] Thereby, the above-mentioned gaps T3 and T4 are formed again, and are placed at a position where the separation control member 196R does not act on the urging member 152R. Figure 25 Status to Figure 26 The state transitions are executed without delay.

[0373] As described above, in the structure of this embodiment, by moving the separation control member 196R from the home position to the first position, the urging member 152R can be rotated and the separation holding member 151R can be moved from the separation holding position to the separation allowing position. As a result, the developing unit 109 can be moved from the separation position to the contact position where the developing roller 9 and the photosensitive drum 104 are in contact with each other. Figure 26The position of the separation control member 196R is Figure 24 The same as in .

[0374] [Developing unit separation operation]

[0375] Next, refer to Figure 26 and Figure 27 , the operation of moving the developing unit 109 from the contact position to the separation position by the separation contact mechanism 150R will be described in detail. For better explanation, these figures are cross-sectional views taken along line CS, in which a portion of the developing cover member 128, a portion of the driving side cartridge cover member 116, and a portion of the driving side bearing 126 are partially omitted.

[0376] The separation control member 196R in this embodiment is configured to Figure 26 152Rm and the first force receiving surface 152Rm of the force applying member 152R come into contact with each other, and the force applying member 152R rotates in the direction indicated by the arrow BB about the force applying member swing axis HC. Then, the first pressing surface 152Rq of the force applying member 152R comes into contact with the first pressure receiving surface 126c of the drive side bearing 126 ( Figure 27 , the developing unit 109 is rotated about the swing axis K in the direction of the arrow V1 from the contact position. Here, the pressed surface 152Rf of the urging member 152R has an arc shape, and the center of the arc is placed so as to coincide with the swing axis K. Thus, when the developing unit 109 moves from the contact position to the separation position, the force received by the pressed surface 152Rf of the urging member 152R from the box pressing unit 121 is directed in the direction of the swing axis K. Therefore, the developing unit 109 can be operated in a manner that does not hinder the rotation in the direction of the arrow V1. In the separation holding member 151R, the second regulated surface 151Rk of the separation holding member 151R and the second limiting surface 116d of the driving side box cover member 116 are separated from each other, and the separation holding member 151R is rotated in the direction of the arrow B1 by the urging force of the tension spring 153. Thus, the separation holding member 151R rotates until the second pressure receiving surface 151Re comes into contact with the second pressing surface 152Rr of the urging member 152R, and by the contact, the separation holding member 151R moves to the separation holding position. When the developing unit 109 is moved from the contact position to the separation position by the separation control member 196R and the separation holding member 151R is in the separation holding position, a gap T5 is formed between the separation holding surface 151Rc and the contact surface 116c, as shown in FIG. Figure 27 Here, the developing unit 109 rotates from the contact position toward the separation position and the separation holding member 151 can be moved to the separation holding position. Figure 27The position shown is referred to as the second position of the disconnect control member 196R.

[0377] Thereafter, the separation control member 196R moves in the direction of the arrow W42 and returns to the original position from the second position. Then, while the separation holding member 151R is maintained in the separation holding position, the developing unit rotates in the direction of the arrow V2 by the torque received from the image forming apparatus main assembly 170 and the developing pressure spring 134 to be described later, and the separation holding surface 151Rc comes into contact with the contact surface 116c. That is, the developing unit 109 is in a state in which the separation position is maintained by the separation holding member 151R, and the developing roller 106 and the photosensitive drum 104 are in a state in which they are separated by the gap P1 ( Figure 24 and Figure 42 152R). As a result, the gaps T3 and T4 are formed again, and the separation control member 196R is placed at a position where it does not act on the urging member 152R ( Figure 24 status in ). From Figure 27 Status to Figure 24 The state transitions are executed without delay.

[0378] As described above, in this embodiment, the separation control member 196R moves from the home position to the second position, causing the separation holding member 151R to move from the separation allowing position to the separation holding position. Then, by the separation control member 196R returning from the second position to the home position, the developing unit 109 is brought into a state where the separation holding member 151R maintains the separation position.

[0379] [Detailed Description of Separation Holding Member L]

[0380] Here, reference Figure 28 , the separation holding member 151L will be described in detail.

[0381] Figure 28 Part (a) is a front view of the process cartridge 100 itself with the separation holding member 151L viewed in the longitudinal direction of the driving side, and Figure 28 B and Figure 28 C is a perspective view of the separation and holding member 151L itself. The separation and holding member 151L includes an annular support receiving portion 151La and a separation and holding portion 151Lb that protrudes from the support receiving portion 151La in a radial direction thereof. The free end of the separation and holding portion 151Lb has an arcuate separation and holding surface 151Lc that extends about the separation and holding member swing axis H.

[0382] In addition, the separation holding member 151L has a second regulated surface 151Lk adjacent to the separation holding surface 151Lc. In addition, the separation holding member 151L includes a second pressed portion 151Ld protruding from the support receiving portion 151La in the Z2 direction, and includes an arc-shaped second pressed surface 151Le protruding from the second pressed portion 151Ld in the direction of the separation holding member swing axis H of the support receiving portion 151La.

[0383] Furthermore, the separation holding member 151L is provided with a main body portion 151Lf connected to the support receiving portion 151La, and the main body portion 151Lf is provided with a spring hook portion 151Lg protruding in the direction of the separation holding member swing axis H of the support receiving portion 151La. Furthermore, the main body portion 151Lf is provided with a rotation preventing portion 151m protruding in the Z2 direction, and a rotation preventing surface 151Ln is provided in a direction facing the second pressure receiving surface 151Le.

[0384] [Detailed Description of the Force Applying Member L]

[0385] refer to Figure 29 , the urging member 152L will be described in detail.

[0386] Figure 29 Part (a) is a front view of the urging member 152L viewed in the longitudinal direction of the process cartridge 100, and Figure 29 Parts (b) and (c) are perspective views of the urging member 152L.

[0387] The force applying member 152L is provided with an elliptical support receiving portion 152La having an elliptical shape. Here, the longitudinal direction of the ellipse of the elliptical support receiving portion 152La is depicted by arrow LH, the upward direction is depicted by arrow LH1, and the downward direction is depicted by arrow LH2. In addition, the direction in which the elliptical support receiving portion 152La extends is depicted by HD. The force applying member 152L is provided with a protruding portion 152Lh formed on the downstream side of the elliptical support receiving portion 152La in the direction of arrow LH2. The elliptical support receiving portion 152La and the protruding portion 152Lh are connected to each other by a main body portion 152Lb. On the other hand, the force applying member 152L includes a pushed portion 152Le protruding in the direction of arrow LH1 and in a direction substantially perpendicular to the direction of arrow LH1, and is provided with an arc-shaped pressure receiving surface 152Lf on the downstream side in the direction of arrow LH1 and is also provided with a push limiting surface 152Lg on the upstream side. Furthermore, the urging member 152L has a first accommodation-time restricting surface 152Lv which is a part of the elliptical support receiving portion 152La and is provided on the downstream side in the arrow LH2 direction.

[0388] The protruding portion 152Lh includes a first force receiving portion 152Lk and a second force receiving portion 152Ln. The first and second force receiving portions 152Lk and 152Ln are arranged so as to oppose each other at their ends in the direction of arrow LH2, in a direction substantially perpendicular to the direction of arrow LH2. The first and second force receiving portions 152Lk and 152Ln respectively have first and second force receiving surfaces 152Lm and 152Lp extending in the HD direction and having an arcuate shape. Furthermore, the protruding portion 152Lh is provided with a spring hook portion 152Ls and a locking portion 152Lt protruding in the HB direction. The locking portion 152Lt is provided with a locking surface 152Lu facing the same direction as the second force receiving surface 152Lp.

[0389] Furthermore, the force applying member 152L is a part of the main body portion 152Lb and is placed on the upstream side of the second force receiving portion 152Ln in the direction of the arrow LH2, and has a first pressing surface 152Lq facing the same direction as the second force receiving surface 152Lp. Furthermore, the force applying member 152L is a part of the main body portion 152Lb and is placed on the upstream side of the first force receiving portion 152Lk in the direction of the arrow LH2, and has a first pressing surface 152Lr facing the same direction as the first force receiving surface 152Lm.

[0390] In a state where the process cartridge 100 is mounted in the image forming apparatus main assembly 170 , the LH1 direction is substantially identical to the Z1 direction, and the LH2 direction is substantially identical to the Z2 direction.

[0391] [Assembly of separation / contact mechanism L]

[0392] Next, refer to Figure 16 and Figures 29 to 35 , the assembly of the separation mechanism will be described. Figure 30 1 is a perspective view of the process cartridge 100 as viewed from the drive side after the separation holding member is assembled with the process cartridge 100. As described above, Figure 16 As shown, in the developing unit 109, the outer diameter portion of the cylindrical portion 127a of the non-driving side bearing 127 is fitted into the developing unit support hole portion 117a of the non-driving side cartridge cover member 117. Thus, the developing unit 109 is supported so as to be rotatable relative to the photosensitive drum 104 around the swing axis K. In addition, the non-driving side bearing 127 includes a cylindrical first support portion 127b and a second support portion 127e that protrude in the direction of the swing axis K.

[0393] The outer diameter of the first support portion 127b is matched with the inner diameter of the support receiving portion 151La of the separation holding member 151L to rotatably support the separation holding member 151L. Here, the swing center of the separation holding member 151L assembled to the non-drive side bearing 127 is the separation holding member swing axis H. The non-drive side bearing 127 includes a first retaining portion 127c protruding in the direction of the separation holding member swing axis H. Figure 16 As shown, the movement of the separation holding member 151L assembled to the non-driving side bearing 127 in the direction of the swing axis H is restricted by the first holding portion 127 c in contact with the separation holding member 151L.

[0394] In addition, the outer diameter of the second support portion 127e cooperates with the inner wall of the elliptical support receiving portion 152La of the urging member 152L to support the urging member 152L so that it can rotate and move in the elliptical direction. Here, the swing center of the urging member 152L assembled to the non-driving side bearing 127 is the urging member swing axis HC. Figure 16 As shown, the movement of the urging member 152L assembled to the non-driving side bearing 127 in the direction of the swing axis HE is restricted by the second retaining portion 127 f in contact with the separation retaining member 151L.

[0395] Figure 31 1 is a view of the processing box 100 observed in the direction of the swing axis H of the developing unit after being assembled with the separation holding member 151L. It is a view taken along the line CS, in which a part of the non-drive side box cover member 117 is omitted, so that the fitting part between the elliptical support receiving portion 151La of the force applying member 152L and the cylindrical portion 127e of the non-drive side bearing 127 can be seen. Here, the separation contact mechanism 150L is provided with a tension spring 153, which is used to push the separation holding member 151L to rotate it around the separation holding member swing axis H in the direction of arrow B1 and to push the force applying member 152L in the direction of arrow B3. The direction of arrow B3 is the longitudinal direction LH2 (see FIG. 1 ) of the elliptical support receiving portion 152La of the force applying member 152L. Figure 29 ) is substantially parallel to the direction. The tension spring 153 is assembled between the spring hook portion 151Lg provided on the separation holding member 151L and the spring hook portion 152Ls provided on the urging member 152L. The tension spring 153 is Figure 31 The tension spring 153 applies a force in the direction of arrow F2 to the spring hook portion 151Lg of the separation holding member 151L, thereby applying an urging force for rotating the separation holding member in the direction of arrow B1. In addition, the tension spring 153 applies a force in the direction of arrow F1 to the spring hook portion 152Ls of the urging member 152L, thereby applying an urging force for moving the urging member 152L in the direction of arrow B3.

[0396] The line connecting the spring hook portion 151Lg of the separation retaining member 151L and the spring hook portion 152Ls of the force retaining member 152L is GS. The line connecting the spring hook portion 152Ls of the force applying member 152L and the force applying member swing axis HE is HS. The angle θ3 formed by the line GS and the line HE is selected to satisfy the following inequality (3), where the counterclockwise direction around the spring hook portion 152Ls of the force applying member 152L is positive. As a result, the force applying member 152L is urged to rotate about the force applying member swing axis HE in the direction BA in the figure.

[0397] 0°≦θ3≦90°...(3)

[0398] In this embodiment, the installation positions of the separation holding member 151L and the urging member 152L are as follows. Figure 29 As shown, in the direction of the swing axis K, the separation holding member 151L and the force applying member 152L are arranged on the side (longitudinal outer side) where the non-drive side cartridge cover member 117 of the non-drive side bearing 127 is placed. However, the position to be arranged is not limited to the example, and they may be arranged on the developing frame 125 side (longitudinal inner side) of the non-drive side bearing 127, and the separation holding member 151L and the force applying member 152L may be provided with the non-drive side bearing 127 interposed therebetween. In addition, the arrangement order of the separation holding member 151L and the force applying member 152L may be interchanged.

[0399] The non-driving side bearing 127 is fixed to the developing frame 125 to form the developing unit 109. Figure 16 As shown, in the fixing method in this embodiment, fixing screws 145 and an adhesive (not shown) are used, but the fixing method is not limited to this example, and welding such as welding by heating or pouring and hardening resin may be used.

[0400] Figure 32 Part (a) and Figure 32 Part (b) is a cross-sectional view in which a portion of the non-driving side cover member 117, the tension spring 153 and the separation holding member 151L is partially omitted by the partial section line CS. Figure 32 Part (a) and Figure 32 In part (b), Figure 31 The portion around the urging member swing axis HE and the separation holding portion 151L of the urging member 152L is shown enlarged.

[0401] In the urging member 152L, the first restriction surface 152Lv of the urging member 152L is in contact with the second support portion 127e of the non-driving side bearing 127 by the urging force of the tension spring 153 in the arrow F1 direction. Figure 32 As shown in part (b), the first pressing surface 152Lq of the force member 152L contacts the first pressure surface 127h of the non-drive side bearing 127 to be positioned in an appropriate position. This position is referred to as the accommodating position (reference position) of the force member 152L. In addition, the separation and holding member 151L rotates around the swing axis H of the separation and holding member in the direction of the arrow B1 by the pushing force of the tension spring 153 in the direction of the arrow F2, and the contact surface 151Lp of the separation and holding member 151L contacts the second pressing surface 152Lr of the force member 152L, whereby it is positioned in an appropriate position. This position is referred to as the separation and holding position (restricted position) of the separation and holding member 151L. When the force member 152L moves to the protruding position to be described below, the second pressure surface 151Le of the separation and holding member 151L contacts the second pressing surface 152Lr of the force member 152L to be positioned at the separation and holding position.

[0402] also, Figure 33 yes Figure 31 The periphery of the separation holding portion 151L in the embodiment is enlarged for the sake of convenience of explanation and the illustration of the tension spring 153 is omitted. Here, it will be considered that the process cartridge 100 including the separation contact mechanism 150L is in a state of being transported when the process cartridge 100 is transported. Figure 33 In the case of falling in the direction of arrow JA in the middle. At this time, the separation holding member 151L receives a force that rotates in the direction of arrow B2 around the separation holding swing axis H due to its own weight. When the separation holding member 151L begins to rotate in the direction of arrow B2, for the reasons described above, the rotation preventing surface 151Ln of the separation holding member 151L contacts the locking surface 152Lu of the force applying member 152L, and the separation holding member 151L receives a force in the direction F4 that suppresses the rotation in the direction of arrow B2. As a result, the separation holding member 151L can be prevented from rotating in the direction of arrow B2 during transportation, and the separation state between the photosensitive drum 104 and the developing unit 109 can be prevented from being damaged.

[0403] In this embodiment, the tension spring 153 is mentioned as the urging means for urging the separation and holding member 151L to the separation and holding position and for urging the biasing member 152L to the accommodation position, but the urging means is not limited to this example. For example, a torsion coil spring, a leaf spring, or the like can be used as the urging means for urging the biasing member 152L to the accommodation position and the separation and holding member 151L to the separation and holding position. Furthermore, the urging means can be made of a material that is elastic and can urge the separation and holding member 151L and the biasing member 152L, such as a mold.

[0404] As described above, the developing unit 109 provided with the separating contact mechanism 150L is integrally coupled to the drum holding unit 108 via the non-driving side cartridge cover member 117 as described above ( Figure 30 status in ). Figure 16 As shown in FIG. 1 , the non-driving side cartridge cover 117 of this embodiment has a contact surface 117c. The contact surface 117c is a surface parallel to the swing axis K. In addition, as shown in FIG. Figure 16 and Figure 30 As shown, when the non-driving side cartridge cover member 117 is assembled to the developing unit 109 and the drum holding unit 108, the contact surface 117c faces the separation holding surface 151Lc of the separation holding member 151L placed at the separation holding position.

[0405] Here, the process cartridge 100 includes a developing pressure spring 134 as an urging member for bringing the developing roller 106 into contact with the photosensitive drum 104. The developing pressure spring 134 is assembled between the spring hook portion 117e of the non-driving side cartridge cover member 117 and the spring hook portion 127k of the non-driving side bearing 127. The urging force of the developing pressure spring 134 causes the separation holding surface 151Lc of the separation holding member 151L and the contact surface 117c of the non-driving side cartridge cover member 117 to contact each other. Then, when the contact surface 117cc and the separation holding surface 151Lc contact each other, the posture of the developing unit 109 is positioned so that the developing roller 106 of the developing unit 109 and the photosensitive drum 104 are separated by a gap P1. The state in which the developing roller 106 is separated from the photosensitive drum 104 by the separation holding member 151L by the gap P1 is referred to as the separated position (retracted position) of the developing unit 109 (see Figure 35 part (a)).

[0406] Here, reference Figure 35 , the separation state and the contact state of the process cartridge 100 will be described in detail. Figure 35 17 is a side view of the process cartridge 100 as viewed from the non-driving side, wherein the process cartridge 100 is mounted inside the image forming apparatus main assembly 170 . Figure 35 Part (a) shows a state in which the developing unit is separated from the photosensitive drum 104. Figure 35 Part (b) shows a state in which the developing unit 109 is in contact with the photosensitive drum 104.

[0407] First, in a state where the separation holding member 151L is placed at the separation holding position and the developing unit 109 is placed at the separation position, the pushed portion 152Le of the urging member 152L is pushed in the direction of the arrow ZA. As a result, the protruding portion 152Lh of the urging member 152L protrudes from the process cartridge 100 ( Figure 34117c). This position is referred to as the protruding position of the urging member 152L. As described above, the second pressure receiving surface 151Le of the separation and holding member 151L is in contact with the second pressing surface 152Lr of the urging member 152L via the tension spring 153. Therefore, when the second force receiving portion 152Ln is pressed in the direction of the arrow W42, the urging member 152L rotates in the direction of the arrow BD about the urging member swing axis HE to rotate the separation and holding member 151L in the direction of the arrow B5. When the separation and holding member 151L rotates in the direction of the arrow B5, the separation and holding surface 151Lc is separated from the contact surface 117c, and the developing unit 109 becomes able to rotate from the separation position about the swing axis K in the direction of the arrow V2.

[0408] That is, the developing unit 109 rotates in the V2 direction from the separated position, and the developing roller 106 of the developing unit 109 contacts the photosensitive drum 104. Here, the position of the developing unit 109 where the developing roller 106 and the photosensitive drum 104 contact each other is referred to as a contact position (developing position) ( Figure 34 17d). The position where the separation holding surface 151Lc of the separation holding member 151L is separated from the contact surface 117c is referred to as a separation allowing position (allowing position). When the developing unit 109 is placed at the contact position, the separation holding member 151L is maintained at the separation allowing position by the second limiting surface 151Lk of the separation holding member 151L contacting the second limiting surface 117d of the driving side cartridge cover 116.

[0409] Furthermore, the non-driving side bearing 127 of the present embodiment has a first pressure receiving surface 127h which is a surface perpendicular to the swing axis K. Since the non-driving side bearing is fixed to the developing unit 109, while the developing unit 109 is in the contact position, the developing unit 109 presses the first force receiving portion 152Lk of the force applying member 152L in the direction of the arrow 41. Then, by the first pressing surface 152Lq coming into contact with the first pressure receiving surface 127h, the developing unit rotates in the direction of the arrow V1 about the swing axis K and moves to the separated position ( Figure 34 Here, when the developing unit 109 moves from the contact position to the separation position, the direction in which the first pressure receiving surface 127h moves is determined by Figure 34 Part (a) and Figure 34, which is indicated by the arrow W41 in part (b). In addition, the direction opposite to the arrow W41 is indicated by the arrow W42, and the directions of the arrows W41 and W42 are substantially horizontal directions (X1, X2 directions). The second force receiving surface 152Lp of the force applying member 152L assembled to the developing unit 109 as described above is placed on the upstream side of the first pressure receiving surface 127h of the non-driving side bearing 127 in the direction of the arrow W41. In addition, the first pressure receiving surface 127h and the second force receiving surface 151Le of the separation holding member 151L are arranged at a position where at least a portion of them overlap in the W1 and W2 directions.

[0410] Next, the operation of the separating contact mechanism 150L in the image forming apparatus main assembly 170 will be described.

[0411] [Installing the process cartridge into the imaging device main assembly]

[0412] Next, we will refer to Figure 35 and Figure 36 The following describes the engagement between the separation contact mechanism 150R of the process cartridge 100 and the development separation control unit of the image forming apparatus main assembly 170 when the process cartridge 100 is mounted on the image forming apparatus main assembly 170. For ease of explanation, these figures are sectional views in which a portion of the development cover member 128 and a portion of the non-driving side cartridge cover member 117 are partially omitted by partial section lines CS, respectively. Figure 35 1 is a view seen from the driving side of the process cartridge 100 when the process cartridge is mounted on the cartridge tray 171 (not shown) of the image forming apparatus M and the cartridge tray 171 is inserted into the first mounting position. In this figure, components other than the process cartridge 100, the cartridge pressing unit 121, and the separation control member 196L are omitted.

[0413] As described above, the imaging device main assembly 170 of this embodiment has a separation control member 196L corresponding to the corresponding process cartridge 100 described above. When the process cartridge 100 is placed at the first inner position and the second inner position, the separation control member 196L is arranged on the lower surface side of the imaging device main assembly 170 relative to the separation holding member 151L. The separation control member 196L has a first force application surface 196La and a second force application surface 196Lb that protrude toward the process cartridge and face each other across a space 196Rd. The first force application surface 196Ra and the second force application surface 196Rb are connected to each other by a connecting portion 196Rc on the lower surface side of the imaging device main assembly 170. In addition, the separation control member 196R is rotatably supported by the control metal plate 197 around the rotation center 196Re as the center. The separation member 196R is normally urged in the E1 direction by an urging spring. In addition, the control metal plate 197 is configured to be movable in the W41 and W42 directions by a control mechanism (not shown), so that the separation control member 196R is configured to be movable in the W41 and W42 directions.

[0414] As described above, in association with the transition of the front door 11 of the image forming apparatus main assembly 170 from the open state to the closed state, the cartridge pressing unit 121 is lowered in the direction of the arrow ZA, and the first force applying portion 121a comes into contact with the pressed surface 152Lf of the force applying member 152L. Thereafter, when the cartridge pressing unit 121 is lowered to a predetermined position as the second mounting position, the portion 152Lh of the force applying member 152L moves to the protruding position ( ) where the process cartridge 100 protrudes downward in the Z2 direction. Figure 36 When the operation is completed, such as Figure 36 As shown, a gap T4 is formed between the first force-applying surface 196La of the separation control member 196L and the first force-receiving surface 152Lp of the force-applying member 152L, and a gap T3 is formed between the second force-receiving surface 152Lp and the second force-applying surface 196Lb. The separation control member 196L is then placed in a second mounting position where it does not act on the force-applying member 152L. This position of the separation control member 196L is referred to as the home position. At this point, the first force-receiving surface 152Lp of the force-applying member 152L and the first force-applying surface 196La of the separation control member 196L are arranged to partially overlap in the W1 and W2 directions. Similarly, the second force-receiving surface 152Lp of the force-applying member 152L and the second force-applying surface 196Lb of the separation control member 196L are arranged to partially overlap in the W1 and W2 directions.

[0415] [Contact Operation of Developing Unit]

[0416] Next, refer to Figures 36 to 38, the operation of bringing the photosensitive drum 104 and the developing roller into contact with each other by the separation contact mechanism 150L will be described in detail. For the sake of convenience, a portion of the developing cover member 128, a portion of the non-driving side cartridge cover member 117, and a portion of the non-driving side bearing 127 are partially omitted in the partial section line CS. This is a cross-sectional view.

[0417] As mentioned above, the development input coupling 32 is Figure 24 The developing roller 106 rotates by receiving a driving force from the image forming apparatus main assembly 170 in the direction of the arrow V2. That is, the developing unit 109 including the developing input coupling 32 receives a torque in the direction of the arrow V2 about the swing axis K from the image forming apparatus main assembly 170. In addition, the developing unit 109 also receives an urging force in the direction of the arrow V2 due to the urging force of the above-mentioned developing pressure spring 134.

[0418] like Figure 36 As shown in FIG. 1 , when the developing unit 109 is in the separated position and the separation holding member 151L is in the separated holding position, the developing unit receives the torque and the urging force by the developing pressure spring 134. Even in this case, the separation holding surface 151Lc of the separation holding member 151L contacts the contact surface 117c of the non-driving side cartridge cover member 117, and the posture of the developing unit 109 is maintained at the separated position ( Figure 36 status).

[0419] The separation control member 196L of this embodiment is configured to Figure 36 152Lc and the contact surface 117c are separated from each other. Here, the separation holding member 151L is used to move the separation holding member 151L to the separation allowing position where the separation holding surface 151Lc and the contact surface 117c are separated from each other. Figure 37 The position of the separation control member 196L of the separation allowing position shown is referred to as a first position.

[0420] In this manner, the separation control member 196L moves the separation holding member 151L to the separation allowing position. Then, the developing unit 109 rotates in the V2 direction by the torque received from the image forming apparatus main assembly 170 and the urging force of the developing pressure spring 134, and moves to the contact position ( Figure 37 At this time, the separation holding member 151, which is pushed in the direction of arrow B4 by the tension spring 153, is maintained in the separation allowing position by the second regulated surface 151Lk contacting the second limiting surface 117d of the non-driving side box cover member 117. Thereafter, the separation control member 196L moves in the direction of W42 and returns to the original position. At this time, the force member 152L is rotated in the BC direction by the tension spring 153, and the state is toward the state in which the first pressing surface 152Lq of the force member 152L and the first pressure surface 127h of the non-driving side bearing 127 are in contact with each other ( Figure 38 Thus, the gaps T3 and T4 are formed again, and the separation control member 196L is placed at a position where the force member 152L does not act. Figure 37 Status to Figure 38 The state transitions are executed without delay. Figure 38 The position of the separation control member 196L is Figure 36 The same as in .

[0421] As described above, with the structure of this embodiment, by moving the separation control member 196L from the home position to the first position, the urging member 152L rotates to move the separation holding member 151L from the separation holding position to the separation allowing position. As a result, the developing unit 109 can be moved from the separation position to the contact position where the developing roller 9 and the photosensitive drum 104 are in contact with each other.

[0422] [Developing unit separation operation]

[0423] Next, we will refer to Figure 38 and Figure 39 The operation of moving the developing unit 109 from the contact position to the separation position will be described in detail. Figure 39 It is a cross section in which a part of the developing cover member 128, a part of the non-driving side cartridge cover member 117, and a part of the non-driving side bearing are partially omitted by a partial section line CS, respectively.

[0424] The separation control member 196L in this embodiment is configured to Figure 38152Lb and the first force receiving surface 152Lm of the force applying member 152L come into contact with each other, and the force applying member 152L rotates along the arrow BC centered on the force applying member swing axis HD. Since the first pressing surface 152Lq of the force applying member 152L comes into contact with the first pressure receiving surface 127h of the non-driving side bearing 127, the developing unit 109 rotates from the contact position in the direction of the arrow V1 about the swing axis K ( Figure 39 Here, the pressed surface 152Lf of the urging member 152L has an arc shape, and the center of the arc is placed so as to be aligned with the swing axis K. Thus, when the developing unit 109 moves from the contact position to the separation position, the force received by the pressed surface 152Lf of the urging member 152L from the box pressing unit 121 faces in the direction of the swing axis K. Therefore, the developing unit 109 can be operated so as not to hinder the rotation in the direction of arrow V1. In the separation holding member 151L, the second regulated surface 151Lk of the separation holding member 151L is separated from the second limiting surface 117d of the non-driving side box cover member 117, and the separation holding member 151L is rotated in the direction of arrow B4 by the urging force of the tension spring 153. Thus, the separation holding member 151L rotates until the second pressed surface 151Le comes into contact with the second pressing surface 152LR of the urging member 152L, and the position is moved to the separation holding position by the contact with the second pressing surface 152LR. When the developing unit is moved from the contact position to the separation position by the separation control member 196L and the separation holding member 151L is placed at the separation holding position, a gap T5 is formed between the separation holding surface 151Lc and the contact surface 117c, as shown in FIG. Figure 39 Here, the position where the developing unit 109 rotates from the contact position toward the separation position and the separation holding member 151 can move to the separation holding position is referred to as the second position of the separation control member 196L.

[0425] Thereafter, the separation control member 196L moves in the direction of the arrow W41 and returns to the original position from the second position. Then, while the separation holding member 151L is maintained at the separation holding position, the developing unit rotates in the direction of the arrow V2 by the torque received from the main assembly 170 of the image forming apparatus and the urging force of the developing pressure spring 134, and the separation holding surface 151Lc and the contact surface 117c contact each other. That is, the developing unit 109 is in a state where the separation position is maintained by the separation holding member 151L, and the developing roller 106 and the photosensitive drum 104 are in a state where they are separated by the gap P1 ( Figure 36 and Figure 34152L). Thus, the gaps T3 and T4 are formed again, and the separation control member 196L is placed at a position where the urging member 152L does not act ( Figure 36 status in ). From Figure 39 Status to Figure 36 The state transitions are executed without delay.

[0426] As described above, in the structure of this embodiment, the separation control member 196L moves from the home position to the second position, and the separation holding member 151L moves from the separation allowing position to the separation holding position. And, the separation control member 196L returns from the second position to the home position, and the developing unit 109 is brought into a state in which the separation holding member 151L maintains the separation position.

[0427] So far, the operation of the separation mechanism placed on the drive side of the process cartridge 100 and the operation of the separation mechanism placed on the non-drive side have been described separately, but in this embodiment, they operate in conjunction with each other. That is, when the developing unit 109 is positioned at the separation position by the separation holding member R, the developing unit 109 is substantially simultaneously positioned at the separation position by the separation holding member L, and the same applies to the contact position. Specifically, in Figures 23 to 27 and Figures 35 to 39 The movement of the separation control member 121R and the separation control member 121L described in the figure is performed integrally by a connecting mechanism (not shown). Thus, the timing at which the separation holding member 151R provided on the drive side is placed at the separation holding position and the timing at which the separation holding member 151L provided on the non-drive side is placed at the separation holding position are substantially the same, and the timing at which the separation holding member 151R is placed at the separation allowing position and the timing at which the separation holding member 151L is placed at the separation allowing position are substantially the same. These timings may be different between the drive side and the non-drive side, but in order to shorten the time from when the user starts the print job until the printed matter is discharged, it is desirable to at least position the timing of at least the separation allowing position to be the same. In the present embodiment, the separation holding member swing axis H of the separation holding member 151R and the separation holding member 151L is common, but it is sufficient that the timing of the separation holding member 151R and the separation holding member 151L is substantially the same as described above, and therefore the above example is not restrictive. Similarly, the urging member swing axis HC of the urging member 152R and the urging member swing axis HE of the urging member 152L are mismatched axes, but it is sufficient if the timing of placement at the separation allowing position is substantially the same as above, and therefore, the above example is not restrictive.

[0428] As described above, the drive side and the non-drive side are each provided with the same separation contact mechanism, and they operate substantially simultaneously. Thus, even when the process cartridge 100 is twisted or deformed in the longitudinal direction, the separation amount between the photosensitive drum 104 and the developing roller 9 can be controlled at each end portion in the longitudinal direction. Therefore, variations in the separation amount in the longitudinal direction can be suppressed.

[0429] Furthermore, according to this embodiment, by moving the separation control member 196R(L) in one direction (in the directions of arrows W41 and W42) between the home position, the first position, and the second position, the contact and separation states between the developing roller 106 and the photosensitive drum 104 can be controlled. Consequently, the developing roller 106 can be brought into contact with the photosensitive drum 104 only when forming an image, and can be maintained separated from the photosensitive drum 104 when not forming an image. Consequently, even when image formation is not performed for a long period of time, the developing roller 106 and the photosensitive drum 104 do not deform, and stable image formation can be achieved.

[0430] Furthermore, according to the present embodiment, the urging member 152R(L) that acts on the separation holding member 151R(L) to rotate and move can be positioned at the accommodated position by the urging force of the tension spring 153 or the like. Therefore, when the process cartridge 100 is outside the image forming apparatus main assembly 170, it does not protrude from the outermost shape of the process cartridge 100, and the process cartridge 100 itself can be reduced in size.

[0431] Similarly, the biasing member 152R(L) can be positioned at the storage position by the urging force of the tension spring 153 or the like. Therefore, when the process cartridge 100 is to be mounted in the imaging device main assembly 170, the process cartridge 100 can be mounted by moving it in only one direction. Therefore, there is no need to move the process cartridge 100 (tray 171) in the vertical direction. Consequently, no additional space is required for the imaging device main assembly 170, and the main assembly can be reduced in size.

[0432] Furthermore, according to this embodiment, when separation control member 196R(L) is placed in its home position, separation control member 196R(L) is not loaded from process cartridge 100. Consequently, the rigidity required for operating separation control member 196R(L) and the mechanism for operating separation control member 196R(L) can be reduced, and size can be reduced. Furthermore, since the load on the sliding portion of the mechanism for operating separation control member 196R(L) is also reduced, wear of the sliding portion and the generation of abnormal noise can be suppressed.

[0433] Furthermore, according to this embodiment, the developing unit 109 can be maintained in the separated position only by the separation holding member 151R(L) included in the process cartridge 100. Therefore, by reducing the number of components that cause variations in the amount of spacing between the developing roller 106 and the photosensitive drum 104, component tolerances can be reduced and the amount of spacing can be minimized. Since the amount of spacing can be reduced, when the process cartridge 100 is arranged in the main assembly 170 of the imaging device, the area occupied by the developing unit 109 when it moves to the contact position and the separated position can be made smaller, allowing the imaging device to be reduced in size. Furthermore, the space in the developer accommodating portion 29 for the developing unit 109 that moves to the contact position and the separated position can be increased, and thus, a reduced-size and large-capacity process cartridge 100 can be placed in the main assembly 170 of the imaging device.

[0434] Furthermore, according to this embodiment, when the process cartridge 100 is installed, the biasing member 152R(L) can be positioned at the storage position, and the developing unit 109 can be maintained in the separated position solely by the separation-maintaining member 151R(L) of the process cartridge 100. Therefore, when the process cartridge 100 is installed in the imaging device main assembly 170, the process cartridge 100 can be installed by moving it in only one direction. Therefore, there is no need to move the process cartridge 100 (tray 171) vertically. Consequently, space is not required in the imaging device main assembly 170, and the main assembly can be reduced in size. Furthermore, since the amount of separation can be reduced, when the process cartridge 100 is placed in the imaging device main assembly 170, the area occupied by the developing unit 109 when it moves to the contact and separated positions can be reduced, thereby enabling the imaging device to be reduced in size. Furthermore, since the space in the developer accommodating portion 29 for the developing unit 109 moving to the contact and separated positions can be increased, a reduced-sized, high-capacity process cartridge 100 can be placed in the imaging device main assembly 170.

[0435] [Details of the arrangement of the separation contact mechanism]

[0436] Subsequent reference Figure 40 and Figure 41 , the arrangement of the separation contact mechanisms R and L in this embodiment will be described in detail.

[0437] Figure 40 This is an enlarged view of the periphery of the separation and holding member 151R when the process cartridge 100 is viewed from the driving side along the swing axis K (photosensitive drum axis direction) of the developing unit 109. For ease of explanation, this is a cross-sectional view in which a portion of the developing cover member and a portion of the driving-side cartridge cover member 116 are partially omitted along the partial section line CS. Figure 411 is an enlarged view of the periphery of the separation and holding member 151R when the process cartridge 100 is viewed from the non-driven side along the swing axis K (the axis along the photosensitive drum axis) of the developing unit 109. Furthermore, for ease of explanation, this is a cross-sectional view in which a portion of the developing cover member 128 and a portion of the driving-side cartridge cover member 116 are partially omitted along the partial section line CS. Regarding the arrangement of the separation and holding member and the biasing member described below, there is no difference between the driving side and the non-driving side except for the portions that will be described in detail below, and they are common. Therefore, only the driving side will be described, and the same applies to the non-driving side.

[0438] like Figure 40 As shown, the rotation center of the photosensitive drum 104 is point M1, the rotation center of the developing roller 106 is point M2, and the line passing through points M1 and M2 is line N. In addition, the contact area between the separation holding surface 151Rc of the separation holding member 151R and the contact surface 116c of the drive-side cartridge cover member 116 is M3, and the contact area between the second pressure receiving surface 151Re of the separation holding member 151R and the second pressing surface 152Rr of the second urging member 152R is M4. In addition, the distance between the swing axis K and point M2 of the developing unit 109 is distance e1, the distance between the swing axis K and area M3 is e2, and the distance between the swing axis K and point M4 is e3.

[0439] In the structure of this embodiment, the following positions are the relationship when the developing unit 109 is in the separated position and the urging member 152R (L) is in the protruding position. Figure 40 When viewed in the axial direction of the swing axis K (the axial direction of the photosensitive drum) shown, at least a portion of the contact area M3 between the separation and holding member 151R and the drive-side cartridge cover member is placed on the side opposite to the side on which the center of the developing coupling 32 (the swing axis K) is present, with respect to a line N passing through the center of the photosensitive drum 104 and the center of the developing roller. That is, the separation and holding surface 151Rc of the separation and holding member 151R is arranged so that the distance e2 is longer than the distance e1.

[0440] By arranging the separation holding member 151R and the separation holding surface 151Rc in this manner, when the position of the separation holding surface 151Rc varies due to component tolerances, etc., it is possible to suppress variations in the posture of the spaced position of the developing unit 109. That is, variations in the separation holding surface 151Rc have an effect on the separation amount (gap) P1 (see FIG. Figure 42 The influence of part (a)) can be minimized, and the developing roller 106 can be accurately spaced apart from the photosensitive member 104. In addition, there is no need to provide additional space to allow retraction when the developing unit 109 is separated, which leads to a reduction in size of the image forming apparatus main assembly 170.

[0441] In addition, the first force receiving portion 152Rk (Lk) and the second force receiving portion 152Rn (Ln) as the force receiving portion of the force applying member 152R (L) are arranged on the side opposite to the rotation center of the developing coupling 32 relative to the extension line of the line N.

[0442] As described above, the force receiving portions 152Rk (Lk) and 152Rn (Ln) are provided at the end portions in the longitudinal direction. Figure 15 ( Figure 16 ), the cylindrical portion 128b (127a) serving as the supporting portion of the developing unit 109 is provided at the end portion in the longitudinal direction. Therefore, by arranging the force receiving portions 152Rk (Lk) and 152Rn (Ln) at positions opposing the cylindrical portion 128b (127a) of the developing unit 109 (i.e., the swing axis K) with respect to the line N, the functional elements can be efficiently arranged. That is, it leads to a reduction in size of the process cartridge 100 and the image forming apparatus M.

[0443] In addition, the force receiving portions 152Rk and 152Rn are placed at the longitudinal driving side end portions. Figure 15 As shown, the developing drive input gear 132 that receives the drive from the image forming apparatus main assembly 170 and drives the developing roller 106 is provided at the end portion on the driving side in the longitudinal direction. Figure 40 As shown, the urging members 152Rk and 152Rn are placed on the side opposite to the rotation center K of the developing drive input gear 132 (developing coupling portion 132a) as shown by the dotted line relative to the extension line of the line N. With this arrangement, functional elements can be efficiently arranged. That is, it leads to a reduction in size of the process cartridge 100 and the image forming apparatus M.

[0444] In addition, the contact portion between the separation and holding member 151R and the urging member 152R is arranged so that the distance e3 is longer than the distance e1. As a result, the separation and holding member 151R and the drive-side cartridge cover member 116 can contact each other with a relatively light force. That is, the developing roller 106 and the photosensitive drum 104 can be stably separated from each other.

[0445] [Detailed Description of Drive Transmission Mechanism for Photosensitive Drum]

[0446] The drum unit 103 (see FIG. 1 ) for transmitting the driving force from the main assembly of the image forming apparatus to the cartridge 100 will be described. Figure 1 Part (a)) of the structure to drive (rotate) the drum unit.

[0447] Figure 1 、 Figure 13 and Figures 55 to 58The drum unit 103 shown is a drum unit comprising a photosensitive drum, a drum coupling (cartridge side coupling, coupling member) 143 and a drum flange 142 (see FIG. Figure 13 ) unit. The drum unit 103 is a part of the cartridge 100 that is attachable to and detachable from the main assembly of the imaging device. By attaching the drum unit 103 to the main assembly of the device, it can be coupled to the drive transmission unit 203 (see FIG. 20) of the main assembly of the device. Figure 43 and Figure 44 During image formation, the drum unit rotates in the direction of arrow A (see Figure 1 、 Figures 55 to 57 In this embodiment, when the driving side of the drum unit 103 (the side where the drum coupling 143 is located) is viewed, that is, when the drum unit 103 is viewed in the direction of arrow M1B, the rotation direction of the drum unit 103 corresponds to the clockwise direction (see FIG. Figure 1 ). In other words, when viewing the front surface of the drum coupling 143, the rotation direction A of the drum coupling 143 corresponds to the clockwise direction.

[0448] The rotation direction A (see FIG. 1 ) of the drum unit (drum coupling 143 and photosensitive drum 104) will be described below using the movement of the surface of the photosensitive drum 104. Figure 2 and Figure 3 ).exist Figure 2 and Figure 3 In, with Figure 1 Differently, the cartridge is viewed from the non-driven side, and therefore the rotational direction A of the drum unit 103 is counterclockwise.

[0449] like Figure 3 As shown, the surface of the photosensitive drum 104 is charged at a position close to the charging roller 105 inside the box (around the position where it contacts the charging roller). Thereafter, the surface of the photosensitive drum 104 moves to a position where it receives the laser beam U, whereby an electrostatic latent image is formed on the surface. Then, the surface of the photosensitive drum 104 moves to a position close to the developing roller 106 (a position in contact with the developing roller in this embodiment), and the latent image formed on the surface of the photosensitive drum 104 is developed into a colorant image. Thereafter, the surface of the photosensitive drum moves to a position exposed below the box and to the outside of the outer casing of the box. Then, as Figure 2 As shown in FIG. 1 , the surface of the photosensitive drum 104 exposed from the outer casing of the cartridge contacts the intermediate transfer belt 12 a provided in the main assembly of the imaging apparatus. As a result, the toner image is transferred from the surface of the photosensitive drum 104 to the transfer belt 12 a. Thereafter, the surface of the photosensitive drum 104 returns to a position close to the charging roller 105 inside the cartridge.

[0450] In summary, when the photosensitive drum 104 rotates due to the driving force of the coupling 143, a portion of the surface of the photosensitive drum 104 moves from a position close to the charging roller 105 to a position close to the developing roller 106. Thereafter, a portion of the surface of the photosensitive drum 104 is exposed to the outside of the cartridge housing, and then returns to the inside of the cartridge housing and approaches the charging roller 105 again.

[0451] As described above, the cartridge 100 of this embodiment does not have a cleaning device for contacting the photosensitive drum 104 and removing the toner on the surface of the photosensitive drum 104 (see FIG. Figure 3 ). Therefore, the torque required to rotate the drum unit 103 (photosensitive drum 104) within the cartridge 100 is relatively small. With this structure, the drum unit 103 is easily affected by the surrounding environment when being driven, and therefore, the drum unit 103 may be affected by external factors, resulting in unstable rotation speed. For example, in this embodiment, the developing roller 106, charging roller 105, and transfer belt 12a are in contact with the photosensitive drum 104. If the magnitude of the frictional force generated between these devices and the photosensitive drum 104 fluctuates, the speed of the drum unit 103 may fluctuate.

[0452] Therefore, in this embodiment, the structure is such that when the drive transmission unit 203 (see FIG. Figure 43 ) drum drive coupling 180 when making the drum unit (photosensitive drum 104) of the cartridge rotate, requires a predetermined level or higher torque. Thus, the rotation of the drum unit 103 is relatively less affected by external factors, and its rotation speed is stable.

[0453] First, refer to Figure 1 In part (a), the drum coupling 143 of the process cartridge 100 will be described. Figure 1 Part (a) is a perspective view of the drum coupling.

[0454] The drum coupling 143 of this embodiment is manufactured by injection molding polyacetal resin. As a material, a resin material such as polycarbonate resin or polybutylene terephthalate resin, or a resin material provided by mixing these with glass fiber, carbon fiber or the like can be used. Alternatively, a processing method such as die casting or cutting can be used with a metal material such as aluminum, iron or stainless steel.

[0455] Next, refer to Figure 1 、 Figures 55 to 58 , the shape of the drum coupling 143 will be described.

[0456] In the following description of the drum coupling 143, the direction from the photosensitive drum 104 toward the drive transmission unit 230 (drum drive coupling 180) in the axial direction (the direction of the arrow M1A) is referred to as the axial outward direction (outward). In addition, the direction opposite to the outward direction (the direction of the arrow M1B) is referred to as the axial inward direction.

[0457] In other words, in the drum coupling, the outward direction in the axial direction (M1A direction) is a direction from the non-driving side end portion 104b toward the driving side end portion 104a of the photosensitive drum ( Figure 80 Alternatively, the outward direction in the axial direction (M1A direction) is Figure 14 In the direction from the non-driving side case cover 117 of the case 100 toward the driving side case cover 116.

[0458] The inward direction in the axial direction (M1B direction) is a direction from the driving side end portion 104a toward the non-driving side end portion 104b of the photosensitive drum 104 ( Figure 80 Alternatively, the inward direction in the axial direction (M1B direction) is a direction from the driving side case cover 116 toward the non-driving side case cover 117 of the case 100 in the figure.

[0459] like Figure 1 As shown in part (b), the drum coupling 143 is mounted to one longitudinal end portion (driving side end portion) of the photosensitive drum 104. As described above, Figure 1 The shaft portion 143j shown is formed by the driving side cartridge cover member 116 (see FIG. Figure 15 The drum unit 103 is configured to be rotatable in a predetermined rotational direction (the direction of arrow A) during an image forming operation in which a latent image on the surface of the photosensitive drum is developed.

[0460] The drum coupling 143 receives a driving force for rotating the photosensitive drum 104 from the main assembly drive transmitting unit 203 of the main assembly of the apparatus, and also receives a braking force for applying a load against the rotation of the photosensitive drum 104 .

[0461] The drum coupling 143 is provided with a protrusion protruding outward in the axial direction from the surface of the end portion of the shaft portion 143j (see Figure 1 、 Figures 52 to 57 ). The protrusion has a driving force receiving portion 143b as a first side surface (first side portion) for receiving the driving force from the drive transmission unit 203. In addition, the protrusion of the drum coupling 143 includes a braking force receiving portion 143c as a second side surface (second side portion) for receiving the braking force from the drive transmission unit 203.

[0462] The driving force receiving portion 143b is a side surface (side portion) facing the upstream side of the drum unit in the rotational direction A. Furthermore, the braking force receiving portion 143c is a side surface (side portion) facing the downstream side in the rotational direction A.

[0463] In other words, one of the driving force receiving portion 143b and the braking force receiving portion 143c faces one side in the circumferential direction of the drum unit, and the other faces the other side in the circumferential direction. That is, the driving force receiving portion 143b and the braking force receiving portion 143c are side surfaces (side portions) that are opposite to each other in the rotational direction and the circumferential direction.

[0464] Furthermore, the protrusion of the drum coupling 143 has a spiral slope (inclined portion, slope) 143d as a top surface (upper surface, upper portion, upper portion). The slope (top surface) 143d is a portion facing outward in the axial direction (the direction of the arrow MA1). That is, the slope 143d is a portion facing the side opposite to the non-driving side end portion of the drum unit (that is, the side where the drum flange 142 ( Figure 13 ) on the side where the photosensitive drum 104 is located. In other words, the spiral slope (top surface) 143d of the coupling 143 is a portion facing the side opposite to the side where the photosensitive drum 104 is located.

[0465] The spiral inclined surface 143d is inclined so as to be outward in the axial direction (the direction of arrow MA1) toward the upstream side in the rotational direction (the upstream side in the direction of arrow A). In other words, the inclined surface 143d is inclined so as to be away from the non-driven side of the drum unit 103 as it goes toward the upstream side in the rotational direction. In other words, the inclined surface 143d is inclined so as to be away from the photosensitive drum as it goes toward the upstream side in the rotational direction.

[0466] In other words, the spiral slope 143d extends from upstream to downstream in the rotational direction toward the drum unit and the non-driven end of the box. That is, when the distance of the spiral slope 143d from the non-driven end of the box is measured in the axial direction, the distance becomes shorter toward the downstream in the rotational direction.

[0467] The spiral inclined surface 143d includes a downstream portion (downstream top surface, downstream inclined surface, downstream inclined portion, downstream guide portion) 143d1 sandwiched between the driving force receiving portion 143b and the braking force receiving portion 143c in the rotation direction of the drum unit. In addition, the inclined surface 143d has an upstream portion (upstream side top surface, upstream side inclined surface, upstream side inclined portion, upstream guide portion) 143d2. The upstream portion 143d2 of the spiral inclined surface 143d is provided upstream of the driving force receiving portion 143b and the downstream portion 143d1 of the spiral inclined surface 143d in the rotation direction (see FIG. Figures 55 to 58 ).

[0468] Furthermore, since the length of the inclined surface 143 d is measured along the rotational direction of the drum unit, the length of the upstream-side inclined surface 143 d 2 is greater than the length of the downstream-side inclined surface 143 d 1 .

[0469] The upstream side portion (upstream side inclined surface) 143d2 of the inclined surface 143d is provided on the inner side (the side closer to the axis L) of the driving force receiving portion 143b in the radial direction. That is, the upstream side portion (upstream side top surface, upstream side inclined surface) 143d2 of the inclined surface 143d is provided closer to the axis L ( Figure 1 Axis L( Figure 1 Part (a)) is an axis (rotation axis) serving as a rotation center of the coupling 143 and the photosensitive drum 104.

[0470] In addition, the protrusion of the drum coupling 143 is provided with a circular hole portion 143a as an opening for engaging with the positioning boss (positioning portion) 180i of the drum drive coupling 180 and positioning the axes of each other. The circular hole portion 143a has a circular opening whose cross section is perpendicular to the axis L of the drum coupling 143 and extends along the axis L.

[0471] The protrusion of the drum coupling 143 includes a protrusion along the axis L (see Figure 1 The shaft portion 143p (see Figure 1 ), and the circular hole portion 143a is formed inside the shaft portion 143p. The shaft portion 143p is a portion for forming the circular hole portion 143a.

[0472] The shaft portion 143p and the circular hole portion 143a extend in alignment with the axis L. By forming the circular hole portion 143a, the drum unit is rotated from the rotation axis L (see FIG. Figure 1 The space from the portion (a) to the inner surface of the drum coupling 143 is an open space. The diameter of the shaft portion 143p is smaller than that of the above-mentioned shaft portion 143j.

[0473] The drum coupling 143 has a Figure 1 The driving force receiving portion 143b, the braking force receiving portion 143c and the spiral slope 143d are arranged at two positions so as to be separated by 180 degrees in the circumferential direction, thereby providing a first coupling portion 143r and a second coupling portion 143s (see FIG. Figure 58 ).

[0474] Each coupling portion includes a driving force receiving portion 143b, a braking force receiving portion 143c and a spiral slope 143d, and the first coupling portion 143r and the second coupling portion 143s are placed at positions symmetrical about the axis.

[0475] The driving force receiving portion 143b, the braking force receiving portion 143c and the spiral slope 143d are arranged around the above-mentioned circular hole portion 143a and the shaft portion 143p. The driving force receiving portion 143b, the braking force receiving portion 143c and the spiral slope 143d are located farther from the axis L of the drum unit than the circular hole portion 143a and the shaft portion 143p.

[0476] Next, refer to Figure 43 、 Figure 44 and Figure 59 Next, the structure of the main assembly side drive transmission unit 203 provided on the main assembly side of the apparatus will be described. The drive transmission unit 203 is a unit for rotationally driving the drum coupling 143 by being connected (engaged) with the drum coupling 143.

[0477] Figure 43 It is an exploded perspective view of the main assembly side drive transmission unit 203. Figure 59 yes Figure 43 An enlarged perspective view of the portion shown. Figure 44 It is a sectional view of the main assembly side drive transmission unit 203 .

[0478] The drive gear 201 is rotatably supported by a support shaft 202 fixed to a frame (not shown) of the main assembly 170 of the apparatus, and a driving force is transmitted from a motor (not shown) to rotate the drive gear 201. The drum drive coupling 180 includes a cylindrical portion 180c and a flange portion 180a provided at an end thereof, and the flange is assembled and supported by the assembly portion 201a of the drive gear 201. In addition, the drum drive coupling 180 is provided with a rotation stop portion 180b protruding from the flange portion 180a, and the rotation stop portion 180b receives the driving force when it rotates in contact with the rotation stop portion 201b of the drive gear 201. The drive transmission unit 203 includes a plurality of components inside the cylindrical portion 180c of the drum drive coupling 180.

[0479] The components arranged inside the cylindrical portion 180c are as follows. There are a brake member 206 supported and stopped by the support shaft 202, a brake transmission member 207 connected to the brake member 206 to transmit braking force, a first brake engagement member 204 and a second brake engagement member 208 engaged with the braking force receiving surface 143c of the drum coupling 143, and a brake engagement spring 211 and a drum drive coupling spring 210 arranged along the axis M1 and generating an urging force in the direction of the axis M1 (axial direction). The axis M1 is the rotational axis of the main assembly-side drive transmission unit 203.

[0480] The shape of each component arranged inside the main assembly drive transmission unit 203 will be described. The first brake engaging member 204 includes a cylindrical portion 204d, a flange portion 204a, and a coupling engaging portion 204b that projects like a claw and engages with the drum coupling 143. A portion of the cylindrical portion includes a rotation stopping recess 204c that engages with a rotation stopping protrusion 208c of the second brake engaging member 208, which will be described below.

[0481] The second brake engaging member 208 includes a flange portion 208a, a coupling engaging portion 208b that protrudes in the form of a claw and engages with the drum coupling 143, and a rotation stopping protrusion 208c that engages with the rotation stopping recess 204c of the first brake engaging member 204. Since the second brake engaging member 208 is prevented from rotating relative to the first brake engaging member 204, the first brake engaging member 204 and the second brake engaging member 208 rotate integrally with each other. In addition, the first brake engaging member 204 and the second brake engaging member 208 are connected so as to also move integrally in the axial direction.

[0482] Thus, the first brake engaging member 204 and the second brake engaging member 208 may be collectively referred to simply as the brake engaging members ( 204 , 208 ).

[0483] The first brake engaging member 204 is an outer brake engaging member provided on the outer side in the radial direction, and the second brake engaging member 208 is an inner brake engaging member provided on the inner side in the radial direction.

[0484] The brake transmission member 207 includes a flange portion 207a and a shaft portion 207b. The flange portion 207a is provided with a protrusion 207e, which engages with a protrusion 204e provided on the flange portion 204a of the first brake engagement member 204. The flange portion 207a of the brake transmission member 207 is provided between the flange portion 204a of the first brake engagement member 204 and the flange portion 208a of the second brake engagement member 208, with a clearance (gap) G ( Figure 44 ). In the axial direction M1A, when the brake transmission member 207 is at the protrusion 207e of the brake transmission member 207 relative to the first brake engagement member 204 (see Figure 43 and Figure 59) is in a position where the protrusion 207e is engaged with the protrusion 204e of the first brake engaging member 204, the first brake engaging member 204 and the second brake engaging member 208 rotate integrally. On the other hand, when the brake transmission member 207 is in a position in the axial direction relative to the first brake engaging member 204 where the protrusion 207e is not engaged with the protrusion 204e, the brake transmission member 207 does not restrict the rotation of the first engaging member 204 and the second engaging member 208. That is, the first brake engaging member 204 and the second brake engaging member 208 are rotatable relative to the brake transmission member 207. The shaft portion 207b has a non-circular cross-section and engages with the engagement hole 206c of the brake member 206, which will be described below, so that the brake transmission member 207 and the brake member 206 rotate integrally.

[0485] Braking member 206 is divided into two parts, a fixed side 206a and a rotating side 206b, but they are integrated in the axial direction by a retainer (not shown). Fixed side 206a is supported by support shaft 202 and is also fixed in rotation about the axis. On the other hand, rotating side 206b can rotate around support shaft 202, but rotates while receiving a braking force (load) in the rotational direction from fixed side 206a. The method for generating the braking force can be appropriately selected from those using friction and viscosity.

[0486] The brake engaging members (204, 208) are connected to the brake member 206 via the brake transmission member 207 as described above. Therefore, the rotational torque of the brake engaging members (204, 208) increases due to the influence of the load (braking force) generated by the brake member 206. The brake engaging spring 211 is a compression coil spring and is provided so as to be sandwiched and compressed between the end face 206d of the brake member 206 and the flange portion 204a of the first brake engaging member 204. Therefore, the spring 211 applies a repulsive force (urging force, elastic force) to each of the end face 206d of the brake member 206 and the flange portion 204a of the first brake engaging member 204.

[0487] The drum drive coupling spring 210 is a compression coil spring, and is provided so as to be sandwiched and compressed between the end face 206 d of the brake member 206 and the flange portion 207 a of the brake transmission member 207. Therefore, the spring 210 applies a repulsive force (urging force, elastic force) to each of the end face 206 d of the brake member 206 and the flange portion 207 a of the brake transmission member 207.

[0488] The brake transmission member 207 directly receives the repulsive force of the drum drive coupling spring 210 while receiving the repulsive force of the brake engagement spring 211 through the flange portion 204a of the first brake engagement member 204. The protrusion 207f at the end of the brake transmission member 207 in the axial direction M1A abuts against the contact surface 180f of the drum drive coupling 180 (see FIG. Figure 44 ).

[0489] Thus, the drum drive coupling 180 also receives the force of the drum drive coupling spring 210 and the brake engagement spring 211 through the brake transmission member 207. Due to the force of the springs 210 and 211, the drum drive coupling 180 tends to move. Therefore, the movement of the drum drive coupling 180 in the direction of arrow M1B is limited by the axial direction limiting portion 212 (see FIG. Figure 44 ) is regulated (restricted) so that the drum drive coupling 180 does not fall off from the main assembly side drive transmission unit 203. Specifically, when the drum drive coupling 180 moves a certain distance toward the arrow M1B, the flange portion 180a of the drum drive coupling 180 (see Figure 43 ) and the restriction section 212 (see Figure 44 ) contact. Thus, the movement and fall-off of the drum drive coupling 180 can be suppressed.

[0490] When the drum drive coupling 180 receives a force in the arrow M1A direction from the outside in this state, the drum drive coupling 180 can move in the arrow M1A direction while compressing the springs 210 and 211 .

[0491] Furthermore, when the brake engagement members (204, 208) are engaged with the coupling 143, the coupling engagement portions 204b, 208b may interfere with the coupling 143 (see FIG. Figure 60 In this case, the brake engaging members (204, 208) can enter (retract) deep into the drive transmission unit 203 while compressing the springs 210 and 211 in the direction of arrow M1A (see FIG. Figure 61 ).

[0492] As described above, the brake engaging members (204, 208) are spaced apart from the brake transmitting member 207 by a gap G (see FIG. Figure 44 ). Within the width of the gap G, the brake engaging members (204, 208) can move and retract in the direction M1A relative to the brake transfer member 207. Similarly, the brake engaging members (204, 208) can move in the direction of arrow M1A relative to the drum drive coupling 180 within the width of the gap G. When the brake engaging members (204, 208) move in the direction of arrow M1A relative to the brake transfer member 207 and the drum drive coupling 180, the brake engaging spring 211 is compressed.

[0493] By the brake engaging members ( 204 , 208 ) contacting the brake transfer member 207 which tends to move in the direction of arrow M1A beyond the width of the gap G, the brake transfer member 207 also moves in the direction of arrow M1A together with the brake engaging members ( 204 , 208 ).

[0494] Together with the brake engaging members (204, 208), the drum drive coupling 180 also moves in the direction of arrow M1A. Figure 62 As shown, the drum drive coupling 180 and the first brake engaging member 204 are provided with a protruding engaging portion 180u and an engaging portion 204u, respectively. Therefore, when the brake engaging member 204 moves a predetermined distance or more in the direction of arrow M1A relative to the drum drive coupling 180, the engaging portion 204u pushes the engaging portion 180u to retract the drive coupling 180 in the direction M1A. At this time, not only the spring 211 is compressed, but also the spring 210 is compressed.

[0495] When the brake engaging member (204, 208) moves relative to the brake transfer member 207 in the direction of arrow M1A, the protrusion 207e of the brake transfer member 207 disengages from the protrusion 204e of the first brake engaging member. That is, the brake engaging member (204, 208) is disconnected from the brake transfer member 207, and the braking force is not transmitted from the brake transfer member 207. The brake members (204, 208) can rotate relative to the brake transfer member 207 without receiving the rotational load generated by the brake member 206.

[0496] That is, by retracting the brake engaging member (204, 208) in the direction of arrow M1A, the brake engaging member can be moved from a position where the brake member 206 receives a rotational load (braking force) during rotation to a position where the brake engaging member does not receive a rotational load during rotation. The brake engaging member (204, 208) is configured to reduce the torque required by itself by moving in the M1A direction relative to the brake transmitting member 207 and the drum drive coupling 180.

[0497] Figure 45 20 is a perspective view showing the positional relationship between the drum drive coupling 180 and the brake engaging members ( 204 , 208 ). Figure 45 Part (a) is a perspective view of only the drum drive coupling 180, and Figure 45 Part (b) shows a perspective view of the drum drive coupling 180 and the brake engagement members (204, 208) both included therein. Figure 45 Parts (c) and (d) are diagrams in which the reinforced cylindrical portion 180e of the drum drive coupling 180 is not shown (not visible) for better illustration. The phase of the brake engagement members (204, 208) is Figure 45There is a difference between parts (c) and (d).

[0498] like Figure 45 As shown in part (a) of FIG. 1 , the drum drive coupling (driving force applying member) 180 includes a drive transmitting surface 180 d provided at each of two positions 180 degrees apart from each other in the circumferential direction as a surface (driving force applying portion) that engages with the coupling 143 to transmit the driving force. The drum drive coupling has an axisymmetric shape.

[0499] A through hole 180f communicating in the direction of the axis M1 is provided in a portion other than the drive transmission surface 180d. Through the through hole 180f, the coupling engaging portions 204b and 208b of the first brake engaging member 204 and the second brake engaging member 208 are exposed in a direction facing the coupling 143 (see FIG. Figure 60 ).

[0500] Figure 45 Part (b) shows a state in which the coupling engaging portions 204b and 208b of the first and second brake engaging members 204 and 208 are exposed. The drum drive coupling 180 is provided with a reinforcing cylindrical portion 180e to increase the rigidity of the drive transmitting surface 180d. Figure 45 Part (c) is an illustration in which the reinforced cylindrical portion 180e is not shown for better explanation. Figure 45 Part (c) shows a state in which the coupling engaging portions 204b and 208b are in a close phase relationship with the drive transmitting surface 180d in the rotational direction A. The size of the through hole 180f is selected to be wider than the width of the coupling engaging portions 204b and 208b in the circumferential direction. Therefore, the coupling engaging portions 204b and 208b can move within a predetermined range in the rotational direction in the drum drive coupling 180.

[0501] Figure 45 Part (d) shows a state in which the coupling engaging portions 204b and 208b are in an out-of-phase relationship with the drive transmitting surface 180d in the rotational direction A.

[0502] Next, refer to Figure 1 and Figures 43 to 51 , a method of connecting the main assembly side drive transmission unit 203 of the drive transmission mechanism and the photosensitive member coupling 143 on the process cartridge 100 side will be described.

[0503] [Coupling engagement operation]

[0504] Next, the coupling process between the main assembly side drum drive coupling 180 of the image forming apparatus main assembly 170 and the drum coupling 143 of the process cartridge 100 will be described.

[0505] Figure 46 A sectional view of the image forming apparatus main assembly 170 is shown around the main assembly side drum drive coupling 180. Figure 46 , an overview of the movement of the drum drive coupling 180 on the main assembly side will be described.

[0506] When the user opens the front door 111 ( Figure 4 ) to replace the process cartridge 100, the drive transmission unit 203 moves along the axis M1 in the direction of the arrow M1A via a link mechanism (not shown) connected to the front door 111. That is, the drive transmission unit 203 is in a state of being moved away from the process cartridge 100 and the drum coupling 143 (see FIG. Figure 60 ).

[0507] When the user installs the process cartridge 100 and closes the front door 111, the effect of the above-mentioned connecting rod disappears. Therefore, the drum drive coupling 180, the brake engaging members 204, 208 and the brake transmission member 207 tend to move again in the direction of arrow M1B by the urging force of the drum drive coupling spring and the brake engaging spring 211. At this time, the drum coupling 143 of the process cartridge 100 is ready in the direction of arrow M1B and interferes with the approaching drive transmission unit 203 ( Figure 61 、 Figure 65 and Figure 69 The drum coupling 143 and the drive transmission unit 203 are pressed against each other.

[0508] Under these conditions, the drum drive coupling 180 and the drum coupling 143 of the drive transfer unit 203 are normally disengaged.

[0509] In order to put the drum coupling 143 and the main assembly side drum drive coupling 180 into a normal engagement state, the drive transmission unit 203 needs to be further rotated from the above-mentioned pressed state. That is, the driving process of the drive transmission unit 203 must be advanced until the drum drive coupling 180 on the main assembly side is engaged with the drum coupling 143.

[0510] Furthermore, the process until the engagement is completed can be performed in different modes, and therefore, description will be made by dividing into a plurality of cases depending on the phases of the drum coupling 143 and the main assembly side drum drive coupling 180.

[0511] Figure 47 Part (a) shows the drum coupling 143, and Figure 47 Part (b) shows the drive transmission unit, both of which are viewed in the axial direction. Figure 47 In part (a), the shape of the coupling 143 will be further described. As for the profile of the coupling, the shape varies in the radial direction, depending on the function to be performed. The following structure is provided within the range of the radius indicated by R1 in the figure.

[0512] That is, a positioning hole (opening) 143a, a shield (shield portion) 143g (see FIG. 143b ) that engages with the positioning boss (positioning portion) 180i of the drive coupling 180 are provided. Figure 47 and Figure 1 The shield is a protruding portion for preventing the drive transmission unit 203 from entering in the axial direction. A portion of the spiral slope 143d and a portion of the braking force receiving surface 143c are provided in a range between R1 and R2. The braking force receiving surface 143c is provided in a range between R1 and R2. Figure 47 Part (a) is not visible in the direction of sight and is Figure 1 In the range between R2 and R3, a portion of the driving force receiving portion 143b, a portion of the spiral slope 143d, and a portion of the braking force receiving surface 143c are provided.

[0513] On the other hand, since the shape of the drive transmission unit 203 is also arranged to include different effects in the radial direction, Figure 47 The same symbols R1 to R3 are used in part (b) to indicate the same range as the coupling 143.

[0514] exist Figure 47 In the portion (b) of the drum coupling 143, within the range of the radius indicated by R1, the positioning boss 180i engaged with the positioning hole 143a of the drum coupling 143 and the second brake in contact with the shutter portion 143g depend on the phase of the drum coupling 143. The inward protrusion 208e, which is a part of the coupling engaging portion 208b of the engaging member 208, is arranged. The coupling engaging portion 208b of the second brake engaging member 208 is arranged within the range indicated by R1 to R2. The drive transmission surface 180d and the first brake engaging member 204 are arranged within the range indicated by R2 to R3.

[0515] Figure 48 It is an expanded view of these parts expanded around the rotation axis M1. Figure 48 The process until the drum coupling 143 and the drive transmission unit 203 are engaged with each other will be described.

[0516] Figure 48 The drive transmission unit 203 is shown on the lower side and shows the process of approaching the drum coupling 143 while moving in the direction of the arrow M1B until the engagement is established. Figure 47 The structures within the illustrated radius R1 are indicated by dotted lines, the structures provided in the range between the radius R1 and the radius R2 are indicated by solid lines, and further, the structures provided in the range between the radius R2 and the radius R3 are indicated by solid lines and hatching.

[0517] The drum coupling 143 includes two coupling parts 143s and 143r arranged 180 degrees apart from each other, but for simplicity, only the coupling part 143s will be described below. The description of the coupling part 143s also applies to the coupling part 143r.

[0518] Figure 48 Part (a) shows a state in which the drive transmission surface 180d of the drive transmission unit 203 and the second brake engaging member 208 are close to each other. Figure 48 As shown in part (a) of FIG. 1 , the inclination start portion 143f of the drum coupling 143 and the inward protrusion 208e of the second brake engaging member 208 have the following phase relationship. That is, the inclination start portion 143f of the drum coupling 143 is located on the upstream side of the protrusion 208e in the rotation direction (arrow A).

[0519] Figure 48 Part (b) shows the drive transmission unit 203 from Figure 48 The position shown in part (a) of FIG. 143 is further moved in the direction of arrow M1B. The spiral slope 143d is opposed to and in contact with the inward protrusion 208e of the approaching first brake engaging member 204.

[0520] Figure 48 Part (c) shows a state in which the drive transmission unit 203 moves further in the direction of arrow M1B. The spiral bevel 143d stops the approaching second brake engaging member 208. As a result, the movement of the second brake engaging member 208 in the direction M1B is suppressed. On the other hand, parts other than the second brake engaging member 208 (i.e., the drum drive coupling 180 of the drive transmission unit 203, etc.) move in the direction of arrow M1B. In the drive transmission unit 203, the second brake engaging member 208 is in a state of being relatively pushed in the direction of arrow M1A.

[0521] When this state is reached, as shown in the reference Figure 44 As described above, because second brake engaging member 208 is disconnected from brake member 206, it can rotate without receiving a rotational load. At this time, brake member 206 receives a spring force F1 in the direction of rotation axis M1 via drum drive coupling spring 210 and brake engaging spring 211 disposed within drive transmission unit 203. Helical slope 143d, using the component of spring force F1, moves second brake engaging member 208, which is free of rotational load, in the direction of arrow C. Specifically, second brake engaging member 208 moves downstream in rotation direction A along helical slope 143d.

[0522] Figure 48Part (d) shows the state immediately after the second brake engaging member 208 moves to the downstream side in the rotational direction (the direction of arrow A). The second brake engaging member 208 moves along the spiral bevel 143d of the drum coupling 143, and further moves in the M1B direction by the amount that the entire drive transmission unit 203 moves in the axial direction M1B, so that the movement trajectory is as shown by arrow D. Therefore, the second brake engaging member 208 moves away from the drive coupling 180 toward the downstream side in the rotational direction A to a position where it can engage with the braking force receiving portion 143c (second side surface, second side portion) of the drum coupling 143. That is, the spiral bevel 143d is a guide portion for guiding the brake engaging member toward the braking force receiving portion 143c. In the present embodiment, the spiral bevel (top surface) 143d serving as the guide portion has a downstream portion 143d1 and an upstream portion 143d2. Downstream portion (downstream inclined surface, downstream top surface, downstream inclined portion) 143d1 is positioned between braking force receiving portion 143c and driving force receiving portion 143b. Upstream portion (upstream inclined surface, upstream top surface, upstream inclined portion) 143d2 is positioned upstream of driving force receiving portion 143b in the rotational direction (direction A). Therefore, second brake engaging member 208 can be smoothly guided from upstream portion 143d2 of inclined surface 143d to braking force receiving portion 143c via downstream portion 143d1.

[0523] Figure 48 Part (e) shows a state in which the drum coupling 143 moves (rotates) in the direction of arrow A through the rotational drive transmitting surface 180 d , and therefore, the braking force receiving portion 143 c contacts the second brake engaging member 208 .

[0524] The drive transmission surface 180 d contacts the driving force receiving portion 143 b to transmit the driving force when the drive transmission unit 203 rotates in the direction of arrow A. The drive transmission surface 180 d is a driving force applying portion that applies the driving force to the drum coupling 143 .

[0525] The drum coupling 143 , which rotates by receiving the driving force from the drive transmitting surface 180 d , also receives the braking force by contacting (engaging) the second brake engaging member 208 through the braking force receiving portion 143 c .

[0526] Figure 48 Parts (a) to (e) of FIG. 1 only show the second brake engaging member 208 of the first brake engaging member 204 and the second brake engaging member 208 as the brake engaging member. However, the first brake engaging member 204 (see FIG. Figure 43 ) is connected to the second brake member 208 so as to move integrally with the second brake member 208. Figure 48 Part (a) to Figure 48 During the process shown in part (e), the first brake engaging member 204 also moves along the same line as the second brake member 208. Figure 48 In the state shown in part (e) of FIG. 1 , the first brake engaging member 204 is also engaged with the braking force receiving portion 143 c together with the second brake engaging member 208 .

[0527] exist Figure 48 In parts (a) to (e) of FIG. 1 , for simplicity of description, only the engagement process of the brake engagement members (204, 208) and the drum drive coupling 180 with the coupling portion 143s is shown. Similar to the coupling portion 143s, the coupling 143r is also engaged with the brake engagement members (204, 208) and the drum drive coupling 180. The engagement state of the brake engagement members (204, 208) and the drum drive coupling relative to the coupling 143r is shown in FIG. Figure 76 is shown in part (a).

[0528] Here, to help identify the process described so far, we will use Figures 60 to 64 The perspective diagram is described. Figures 60 to 64 , for better illustration, a portion of the drum drive coupling 180 is not shown and the internal shape is not covered.

[0529] Figure 60 is shown with the above Figure 48 That is, the tilt start portion 143f of the drum coupling 143 is on the upstream side of the protrusion 208e in the rotation direction (arrow A), and the drive transmission surface 180d of the drive transmission unit 203 and the second brake engaging member 208 are close to each other. Figure 61 A state is shown in which the drive transmission unit 203 has moved from this state in the direction of arrow M1B.

[0530] Figure 61 Shown corresponding to Figure 48 The state of part (b) is changed, and the spiral slope 143d is opposite to and contacts the inward protrusion 208e of the approaching second brake engaging member 208. The drive transmission unit 203 and the drum coupling 143 are relatively close to each other until they contact each other, but the state inside the drive transmission unit 203 does not change. Figure 62 A state is shown in which the drive transmission unit 203 has further moved from this state in the direction of arrow M1B.

[0531] Figure 62 Shown corresponding to Figure 48The state of part (c) in which the spiral slope 143d stops the approaching second brake engaging member 208. Thus, in the drive transmission unit 203, the second brake engaging member 208 is pushed relative to the drum drive coupling 180 in the direction of arrow M1A.

[0532] In this state, as referenced Figure 44 As described above, because second brake engaging member 208 is disconnected from brake member 206, it can rotate without receiving a rotational load. At this time, brake member 206 receives a spring force F1 in the direction of rotation axis M1 via drum drive coupling spring 210 and brake engaging spring 211 disposed within drive transmission unit 203. Helical slope 143d, using the component of spring force F1, moves second brake engaging member 208, which is free of rotational load, in the direction of arrow C. In other words, second brake engaging member 208 rotationally moves downstream in rotation direction A along helical slope 143d.

[0533] Figure 63 shows a state immediately after the second brake engaging member 208 moves to the downstream side in the rotational direction (the direction of arrow A), and corresponds to Figure 48 The second brake engaging member 208 moves along the helical inclined surface 143d of the drum coupling 143 and further moves in the M1B direction by the amount that the entire drive transmission unit 203 moves in the axial direction M1B, with the movement trajectory shown by arrow D. As a result, the brake engaging members (204, 208) move away from the drive coupling 180 toward the downstream side in the rotational direction A to a position where they can engage with the second side surface (braking force receiving portion 143c) of the drum coupling 143. Upon reaching this position, the brake engaging members (204, 208) return to a state where they can generate braking force.

[0534] Figure 64 A state is shown in which the drum coupling 143 moves (rotates) in the direction of arrow A through the rotational drive transmitting surface 180 d , and therefore, the braking force receiving portion 143 c contacts the second brake engaging member 208 . Figure 64 Corresponding to Figure 48 Part (d).

[0535] When the drum drive coupling 180 of the drive transmission unit 203 is Figure 64 When the drum coupling 143 rotates in the direction of arrow A, the drive transmission surface 180d contacts the drive force receiving portion 143b to transmit the drive force. The drum coupling 143 rotates by receiving the drive force from the drive transmission surface 180d and also receives the braking force by contacting (engaging) the second brake engaging member 208 through the braking force receiving portion 143c (see FIG. Figure 48 Part (e)).

[0536] In short, through Figure 48 Parts (a) to (e) and Figures 60 to 64 In the process shown, the brake engagement members (204, 208) are moved relative to the drum drive coupling 180 and the drum coupling 143 as follows.

[0537] The brake engaging members (204, 208) are moved from their positions adjacent to the drive transmitting surface 180d ( Figure 48 Part (a) and Figure 60 ) moves to a position where the drum coupling 143 is clamped between the drive transmitting surface 180d and the brake engaging member (204, 208) ( Figure 48 Part (d) and Figure 64 )).

[0538] When the drive transmission surface 180d is Figure 48 Part (d) and Figure 64 When the drum coupling 143 rotates with the drive transmission surface 180d, the drum coupling 143 also rotates with the drive transmission surface 180d to achieve Figure 48 The drum coupling 143 is then rotated in the direction of arrow A by the driving force received from the drum drive side coupling 180 while receiving an appropriate load (braking force) from the brake coupling members (204, 208). Therefore, the torque required by the drum drive coupling 180 to rotate the drum unit is not too small and is appropriate, so that the rotation drive of the drum unit is stable.

[0539] Next, refer to Figure 49 In parts (a) to (e), another mode of engagement of the drum drive coupling 180 and the brake engagement members (204, 208) with the drum coupling 143 will be described. The drum coupling 143 has two coupling portions 143s and 143r, but for simplicity, only the coupling portion 143s will be described.

[0540] like Figure 49 As shown in part (a) of FIG. 1 , a case where the phases of the inclination start portion 143 f of the drum coupling 143 and the inward protrusion 208 e of the second brake engaging member satisfy the following relationship will be described. That is, a case where the inclination start portion 143 f of the drum coupling 143 is on the downstream side relative to the inward protrusion 208 e in the rotation direction (arrow A) will be described.

[0541] Figure 49 Part (a) shows a state in which the drive transmission surface 180d of the drive transmission unit 203 and the second brake engaging member 208 are close to each other.

[0542] The shutter portion 143 g of the drum coupling 143 comes into contact with the inward protrusion 208 e of the second brake engaging member 208 approaching in the M1B direction.

[0543] Next, Figure 49 Part (b) shows a state in which the shutter portion 143g stops (prevents) the approaching advancement of the second brake engaging member 208. Here, the drum drive coupling 180, which is a component of the drive transmission unit 203, does not contact the shutter portion 143g and, therefore, cannot stop the advancement in the M1B direction. That is, the shutter portion 143g does not interfere with the shape of the drum drive coupling 180 because its position is different in the radial direction. On the other hand, the second brake engaging member 208 has an inward protrusion 208e at its free end in the M1B direction. Since the inward protrusion 208e protrudes inwardly in the radial direction, it contacts the shutter portion 143g of the drum coupling 143.

[0544] By movement of the drum drive coupling 180 only in the M1B direction, the second brake engaging member 208 moves in the M1A direction relative to the drum drive coupling 180. As described above, by this relative movement, the second brake engaging member 208 transitions to a state where it can rotate without receiving a rotational load.

[0545] Then, Figure 49 Part (c) shows a state in which the drive transmission unit 203 has started rotating in the rotation direction A. First, when the drum drive coupling 180 starts rotating in the A direction, it is pushed by the drum drive coupling 180 and the second brake engaging member 208 also starts rotating in the A direction.

[0546] The helical slope 143d of the drum coupling 143 moves the second brake engaging member 208 in the direction of arrow C from the point where the inward protrusion 208e passes the slope start portion 143f. That is, the second brake engaging member 208 moves toward the downstream side of the rotational direction A and the M1B direction.

[0547] Figure 49 Part (d) is shown in Figure 48 Part (d) shows the state where the second brake engaging member 208 has moved along the helical inclined surface 143d of the drum coupling 143 and passed over the inclined surface 143d. At this time, the entire drive transmission unit 203 has further moved in the axial direction M1B. Therefore, the second brake engaging member also moves in the M1B direction. The first brake engaging member 204 moves along the line indicated by arrow D.

[0548] Subsequent joining operations and Figure 48 The same as described in part (d), and the subsequent bonding completion status is as follows Figure 48. As shown in part (e). In the present embodiment, the shroud portion 143g is continuous with the upstream side (upstream side slant, upstream side top surface) 143d2 of the spiral slope 143d. The inclination start portion 143f is a boundary portion between the shroud portion 143g and the spiral slope 143d. Therefore, the second braking engagement member 208, whose movement is blocked by the shroud portion 143g, can smoothly transition to a state of contact with the spiral slope 143d as the drive transmission unit 203 rotates. However, the structure is not necessarily limited to this example structure, and a space may be provided between the shroud portion 143g and the slope 143d.

[0549] Also in Figure 49 Part (a) to Figure 49 In part (d) of FIG. 1 , only the second brake engaging member 208 of the brake engaging members (204, 208) is shown. However, as described above, Figure 49 Part (a) to Figure 49 During the process of part (d), the first brake engaging member 204 (see Figure 43 ) moves integrally with the second brake engaging member 208.

[0550] Here, to help identify the reference Figure 49 Part (a) to Figure 49 The process described in part (d) will be referred to again Figures 65 to 68 The perspective diagram is described. Figures 65 to 68 , for better illustration, a portion of the drum drive coupling 180 is not shown and the internal shape is not covered.

[0551] Figure 65 14. The drive transmission surface 180d of the drive transmission unit 203 and the second brake engaging member 208 are shown in a state where they are approaching each other. At this time, the shutter 143g of the drum coupling 143 is in contact with the second brake engaging member 208 approaching in the M1B direction. Figure 65 Corresponding to Figure 49 Part (a).

[0552] Next, Figure 66 1B shows a state where the drum drive coupling 180 has been moved to the right (M1B direction) in the axial direction relative to the second brake engaging member 208. Figure 66 , the shutter portion 143g is in a state of stopping (blocking) the advancement of the approaching second brake engaging member 208.

[0553] Figure 66 Corresponding to Figure 49The second brake engaging member 208 moves to the left (M1A direction) in the axial direction relative to the drum drive coupling 180. As described above, through this relative movement, the second brake engaging member 208 is transformed into a state where it can rotate without receiving a rotational load.

[0554] Then, Figure 67 A state in which the drive transmission unit 203 has started rotating in the rotation direction A is shown. Figure 67 Corresponding to Figure 49 The helical inclined surface 143d of the drum coupling 143 moves the second brake engaging member 208 in the direction of arrow C from the point where the second brake engaging member 208 passes the inclined start portion 143f. Figure 68 Corresponding to Figure 49 Part (d). Figure 68 In the state shown, the first brake engaging member 204 moves along the spiral inclined surface 143d of the drum coupling 143, as shown in FIG. Figure 48 Part (d) and Figure 63 Furthermore, the first brake engaging member 204 also moves in the M1B direction by the amount of movement of the entire drive transmission unit 203 in the axial direction M1B.

[0555] Then, as described above, the entire drive transmission unit 203 continues to rotate to complete the connection, resulting in Figure 48 The same status as part (e).

[0556] Next, refer to Figure 50 Part (a) to Figure 50 In part (d), another mode of engagement of the drum drive coupling 180 and the brake engagement members (204, 208) with the drum coupling 143 will be described. The drum coupling 143 includes two coupling portions 143s and 143r, but for simplicity, only the coupling portion 143s will be described.

[0557] like Figure 50 As shown in part (a) of FIG. 1 , a case where the phases of the inclination start portion 143 f of the drum coupling 143 and the inward protrusion 208 e of the second brake engaging member satisfy the following relationship will be described. That is, a case where the inclination start portion 143 f of the drum coupling 143 is located on the downstream side in the rotation direction (arrow A) will be described.

[0558] Figure 50 Part (a) shows a state in which the drive transmission surface 180d of the drive transmission unit 203 and the second brake engaging member 208 are separated from each other.

[0559] Next, Figure 50Part (b) shows a state in which the shutter portion 143g stops the advancement of the approaching second brake engaging member 208. Here, the drum drive coupling 180, which is a component of the drive transmission unit 203, does not contact the shutter portion 143g, and therefore, the advancement cannot be stopped. As a result, the second brake engaging member 208 moves relative to the drum drive coupling 180 in the M1A direction. As described above, through this relative movement, the second brake engaging member 208 is transformed into a state in which it can rotate without receiving a rotational load. Here, the shutter portion 143g does not interfere with the shape of the drum drive coupling 180 because the positions are different in the radial direction.

[0560] Then, Figure 50 Part (c) shows a state in which the drive transmission unit 203 rotates in the rotation direction A and contacts the second brake engaging member. This is a state in which the second brake engaging member 208 itself does not start to rotate so that it stops at this position, while the drum drive coupling 180 rotates and contacts the second brake engaging member 208. Thereafter, by further rotation, the second brake engaging member 208 and the drum drive coupling 180 rotate integrally.

[0561] Figure 50 Part (d) shows a state in which the second brake engaging member 208 is further rotated and has passed the tilt start portion 143f of the drum coupling 143. When this state is reached, the second brake engaging member 208 moves in the direction of arrow C, as shown in FIG. Figure 48 The subsequent operations are the same as those described above, and therefore the description is omitted.

[0562] Also in Figure 50 Part (a) to Figure 50 In part (d) of FIG. 1 , only the second brake engaging member 208 of the brake engaging members (204, 208) is shown. However, as described above, in Figure 50 Part (a) to Figure 50 During the process of part (d), the first brake engaging member 204 (see Figure 43 ) also moves integrally with the second brake engaging member 208.

[0563] Here, to help identify the reference Figure 50 Part (a) to Figure 50 The process described in part (d) will be referred to again Figures 69 to 72 The perspective diagram is described. Figures 69 to 72 , for better illustration, a portion of the drum drive coupling 180 is not shown and the internal shape is not covered.

[0564] Figure 69 Corresponding to Figure 50, and shows a state in which the drive transmission surface 180d of the drive transmission unit 203 and the second brake engaging member 208 are separated by a gap G1.

[0565] Next, Figure 70 Corresponding to Figure 50 Part (b) of FIG. 1 shows a state in which the entire drive transmission unit 203 has moved in the M1B direction. This is a state in which the shutter portion 143g has stopped the approaching second brake engaging member 208, and the drum drive coupling 180 has moved to the right in the axial direction (M1B direction) beyond the second brake engaging member 208. At this time, the second brake engaging member 208 has moved to the left (M1A direction) relative to the drum drive coupling 180. As described above, through this relative movement, the second brake engaging member 208 is transformed into a state in which it can rotate without receiving a rotational load.

[0566] Then, Figure 71 Corresponding to Figure 50 , and shows a state in which the drum drive coupling 180 of the drive transmission unit 203 contacts the second brake engaging member 208 by rotating in the rotational direction A.

[0567] Since the second brake engaging member 208 cannot rotate without receiving the rotational force from the drum drive coupling 180, the second brake engaging member 208 does not rotate immediately after the driving of the drive transmission unit 203 starts and remains in the initial position. That is, only the drum drive coupling 180 starts rotating in the A direction in advance. Therefore, Figure 71 The state shown is where the drum drive coupling 180 is in contact with the second brake engaging member 208 .

[0568] Figure 72 Corresponding to Figure 50 , and shows a state in which, by the engagement between the drum drive coupling 180 and the second brake engaging member 208, not only the drum drive coupling 180 but also the second brake engaging member 208 starts to rotate in the direction A. More specifically, this is a state in which, by the second brake engaging member 208 being pushed by the drum drive coupling 180 to rotate in the direction A, the second brake engaging member 208 passes through the inclined starting portion 143f of the drum coupling 143. When this state is reached, the second brake engaging member 208 is guided by the inclined surface 143d and moves in the direction along the inclined surface 143d (the direction of arrow C), as shown in FIG. Figure 48 Part (c) and Figure 62 As described in.

[0569] Subsequent operations are similar to the above references Figure 48 Part (c) to Figure 48 Part (e) and Figures 62 to 64 Those described are the same, and therefore, description thereof is omitted here.

[0570] As described above, when the cartridge 100 is mounted on the main assembly of the image forming apparatus, the phase (disposition) of the drive transmission unit 203 relative to the drum coupling 143 is not predetermined ( Figure 48 Part (a)), Figure 49 (a) Figure 50 Part (a) Figure 60 、 Figure 65 、 Figure 69 ). However, in any case, the drum coupling 143 can be connected to the drive transfer unit 203. The drive transfer unit 203 includes not only the drum drive coupling 180 but also brake engagement members (204, 208), both of which the drum coupling 143 can engage.

[0571] Next, refer to Figure 51 , a structure for aligning the axes of the drive transmission unit 203 and the drum coupling 143 in the process of connecting them will be described. Figure 51 is a cross-sectional view of the drive transmission unit 203 and the drum coupling 143, and Figure 51 Part (a) shows the shape in the connected state in this embodiment. The circular hole portion 143a of the drum coupling is engaged with the positioning boss 180i of the drum drive coupling 180 so that the axes are aligned with each other. In addition, a tapered guide surface 143h is provided at one end of the circular hole portion 143a. That is, the guide surface 143h has a conical shape as a part of the inner surface of the coupling 143. The guide surface 143h is provided so that when the drive transmission unit 203 is still separated in the axial direction M1B direction, the deviation between each other is eliminated when the engagement is started to align the axes with each other.

[0572] In addition to the present embodiment, the circular hole portion 143a of the drum coupling 143 may be engaged with the positioning boss 180i without providing a guide surface, as shown in FIG. Figure 51 In addition, as shown in part (b) of Figure 6 As shown in part (c), the guide surface 143h may be enlarged to reduce the fit between the circular hole portion 143a and the positioning boss 180i. Figure 51 As shown in part (d) of FIG, the diameter of the circular hole portion 143a can be increased. These arrangements can be selected based on how to determine the relative position and accuracy between the drive transmission unit 203 and the process cartridge 100.

[0573] It is desirable that the circular hole portion 143a has a sufficient length to accommodate the positioning boss 180i. Figure 95As shown, the positioning boss 180i at least enters the range of the area Pb on the axis L of the drum unit. The circular hole portion 143a is formed to include the entire area Pb. That is, the periphery of the axis L opens in the area Pb.

[0574] exist Figure 95 In this embodiment, on the axis L, the range occupied by the braking force receiving portion 143c, the spiral slope (top surface) 143d, the shutter portion 143g and the driving force receiving portion 143b (not shown) is Pa included in the area Pb.

[0575] The structure is such that a projected area Pa of the braking force receiving portion 143c, the inclined surface 143d, the shutter portion 143g and the driving force receiving portion 143b when projected onto the axis L at least partially overlaps a projected area Pb of the circular hole portion 143a.

[0576] As described above, according to the present embodiment, the coupling 143 of the cartridge receives the driving force from the drive transmission unit 203 of the image forming apparatus main assembly. Furthermore, the coupling 143 operates the brake mechanism (brake member 206) inside the drive transmission unit 203 in accordance with the driving force received from the drive transmission unit 203. The drum coupling 143 can receive the braking force through the brake engaging members (204, 208).

[0577] By utilizing this braking mechanism, the load required to drive the cartridge can be set within an appropriate range. Therefore, the cartridge 100 can be driven stably.

[0578] The drum coupling 104 and the drive transmission unit 203 of this embodiment can also be used to rotate components other than the photosensitive drum 104, such as a developing roller and a toner feed roller. However, the drum coupling 104 and the drive transmission unit 203 of this embodiment are particularly suitable for rotating the photosensitive drum 104 for the following reasons.

[0579] Although the box 100 of the present embodiment includes the photosensitive drum 104, it is not provided with a cleaning device that contacts the photosensitive drum 104. Therefore, the torque of the photosensitive drum 104 is relatively small, and when the photosensitive drum 104 is affected by the surrounding environment during its rotational drive, its speed tends to fluctuate. Therefore, the drive transmission unit 203 rotates the photosensitive drum 104 under the condition of a constant load applied to the drum 104. That is, the coupling 143 not only receives the driving force for rotating the photosensitive drum, but also receives the braking force for suppressing the rotation of the photosensitive drum from the drive transmission unit 203. By simultaneously receiving two forces acting on the coupling in different rotational directions, the speed fluctuation of the photosensitive drum 104 (drum unit 103) is suppressed, and the rotation is stable.

[0580] The driving force can be input from the drive transmission unit 203 of the present embodiment to the box provided with a cleaning device through the coupling 143. When the box 100 is provided with a cleaning device (e.g., a cleaning blade) that contacts the surface of the photosensitive drum to remove toner from the photosensitive drum, a frictional force is generated between the photosensitive drum and the cleaning device. This frictional force increases the torque required to rotate the photosensitive drum 104. However, even so, the torque required to rotate the photosensitive drum 104 may not be large enough. At this time, as in the present embodiment, if the coupling 143 can receive the driving force and the braking force from the drive transmission unit 203 at the same time, the torque required to rotate the photosensitive drum 104 is increased, and therefore, the rotation of the photosensitive drum is stable. The box provided with a cleaning device will be described in Embodiment 2 described below.

[0581] In this embodiment, the braking mechanism for applying an appropriate rotational load to the photosensitive drum is not arranged on the cartridge side but on the main assembly side of the image forming apparatus, more specifically, in the drive transmission unit 203. Therefore, it is not necessary to provide a braking mechanism on the process cartridge, which is an object to be replaced after use (a detachable mountable unit). This can contribute to miniaturization and cost reduction of the process cartridge.

[0582] Furthermore, the coupling 143 has a shape that allows it to smoothly engage with both the driving force applying member (drum drive coupling 180) and the braking force applying member (brake engaging member (204, 208)) provided in the drive transmission unit 203. For example, the coupling 143 is provided with a spiral slope 143d (inclined portion, guide portion, upper surface, upper portion) and a shutter portion 143f so that it can be easily and smoothly connected to the drive transmission unit 203.

[0583] In the following, we will refer to Figure 79 The shape of the coupling 143 of this embodiment will be described in detail.

[0584] The coupling 143 includes two coupling parts 143s and 143r, each of which includes an engaging portion 143i and a guide forming portion 143j. The engaging portion 143i is a shaped portion for engaging with a driving force applying member (drum drive coupling 180) or a braking force applying member (brake engaging member (204, 208)). The engaging portion 143i forms a driving force receiving portion 143b, a braking force receiving portion 143c, and a downstream inclined surface 143d1.

[0585] The driving force receiving portion 143b and the braking force receiving portion 143c are engaged with the drum drive coupling 180 and the brake member (204, 208), respectively. The driving force receiving portion (first side surface, first side portion) 143b and the braking force receiving portion (second side surface, second side portion) 143c are formed in a planar shape, but they are not limited to this structure. They can be parts with a curved surface shape or parts with a small area, as long as they can receive the driving force and the braking force, respectively. For example, the edge (ridge line) formed by the engaging portion 143i can form the driving force receiving portion (first side surface, first side portion) 143b or the braking force receiving portion (second side surface, second side portion) 143c.

[0586] Alternatively, the driving force receiving portion 143b and the braking force receiving portion 143c may be portions formed of a plurality of separate regions. That is, the engaging portion 143i may be a set of a plurality of formed portions.

[0587] The driving force receiving portion 143b and the braking force receiving portion 143c are respectively the upstream and downstream portions of the engaging portion 143i. That is, the driving force receiving portion 143b is the side portion facing upstream in the rotational direction, and the braking force receiving portion 143c is the side portion facing downstream in the rotational direction.

[0588] Furthermore, the guide forming portion 143n is a protrusion (extended portion) extending in the rotational direction toward the engaging portion 143i. The top surface (upper portion) of the guide forming portion 143n is an upstream inclined surface (upstream top surface, upstream inclined portion) 143d2. The upstream inclined surface 143d2 is a guide portion (upstream guide portion, upstream guide portion) and an inclined portion for guiding the braking force applying member (brake engaging member (204, 208)) toward the engaging portion 143i.

[0589] That is, the guide portion forming part 143n is a protrusion for forming the upstream side inclined surface 143d2 serving as a guide portion (upstream side guide portion).

[0590] The guide forming portion 143n is adjacent to the engaging portion 143i and extends from upstream to downstream in the rotation direction toward the engaging portion 143i. In addition, the upstream inclined surface 143d2 of the guide forming portion 143n is inclined so as to approach the non-driving end of the photosensitive drum from upstream to downstream in the rotation direction (see FIG. Figure 80 ).

[0591] exist Figure 80, the drum coupling 143 is placed near the first end portion (driving side end portion) 104a of the photosensitive drum 104. That is, the first end portion 104a of the photosensitive drum 104 is an end portion on the side for receiving driving force from the drum coupling 143.

[0592] The end portion on the opposite side of the photosensitive drum 104 relative to the first end portion 104a is the non-driven side end portion (second end portion) 104b. The distances from the non-driven side end portion 104b to the upstream side inclined surface 143d2 are represented by D1 and D2. Distance D1 is the distance measured from the non-driven side end portion 104b of the photosensitive drum to the downstream end of the inclined surface 143d2 in the axial direction parallel to the axis L. Distance D2 is the distance measured from the non-driven side end portion 104b of the photosensitive drum to the upstream side end portion of the upstream side inclined surface 143d2 in the axial direction.

[0593] Here, the distance D1 is shorter than the distance D2. That is, when the distance from the non-driven end portion 104b of the photosensitive drum to the upstream inclined surface 143d2 is measured in the axial direction, the distance becomes shorter toward the downstream in the rotational direction.

[0594] That is, the upstream side inclined surface 143d2 is inclined so as to approach the non-driving side end portion 104b of the photosensitive drum toward the downstream side in the rotation direction A. Not only the upstream inclined surface 143d2 but also the downstream inclined surface 143d1 are inclined in the same direction.

[0595] The distances D1 and D2 can also be considered as the distances from the cartridge housing (i.e., the non-drive side cartridge cover 117: see Figure 14 ) is measured from the non-driving side end to the upstream inclined surface 143d2.

[0596] One of the guide forming portion 143n and the engaging portion 143i may be referred to as a first shape portion, and the other may be referred to as a second shape portion, or the like.

[0597] In this embodiment, the first and second shape portions (i.e., the guide forming portion 143n and the engaging portion 143i) are adjacent to each other and connected to each other. More specifically, the guide forming portion 143n is connected to the engaging portion 143i on the downstream side in the rotational direction. However, although the engaging portion 143i and the guide forming portion 143n are adjacent to each other, they may not be connected but may be provided with a gap therebetween.

[0598] Furthermore, in the present embodiment, the top surface (downstream side slope) 143d1 of the engaging portion 143i is smoothly connected to the top surface (upstream side slope) 143d2 of the guide forming portion 143n to provide one slope (top surface) 143d.

[0599] That is, the top surface (downstream slope) 143d2 of the engaging portion 143i is a portion of the guide portion, similar to the upstream slope 143d1, which has the function of guiding the braking engaging member (204, 208) to a position where the braking engaging member can engage with the braking force receiving portion 143c.

[0600] The downstream slope (downstream top surface) 143d2 does not need to be continuous with the upstream slope (upstream top surface) 143d1. An example of a discontinuous form of the upstream slope 143d2 and the downstream slope 143d1 is as follows: Figure 81 Part (a) and Figure 81 As shown in part (b). Figure 81 Part (a) and Figure 81 In part (b), a modified example is shown in which the upstream inclined surface 143d2 and the downstream inclined surface 143d1 are provided with steps and separated in the axial direction, and the downstream inclined surface 143d1 becomes a flat surface. As described above, a portion of the spiral inclined surface 143d as a guide portion may be flat or may have steps.

[0601] like Figure 48 Part (c), Figure 49 Part (c), Figure 50 Part (d), Figure 62 、 Figure 67 and Figure 72 As shown, the brake engaging member (204, 208) contacts the slope 143d to be guided in the direction of arrow C along the inclination direction of the slope 143. That is, the brake engaging member (204, 208) moves toward the non-driven side (M1B direction) of the photosensitive drum in the downstream direction of the rotation direction.

[0602] After being guided by the inclined surface 143d, the brake engaging member (204, 208) further advances in the axial direction (M1B) toward a space placed downstream of the braking force receiving portion (second side surface) 143c of the drum coupling 143 (see Figure 48 Part (d), Figure 49 Part (d), Figure 63 、 Figure 68 ). Therefore, the brake engaging member (204, 208) can engage with the braking force receiving portion 143c.

[0603] The brake engaging members (204, 208) are guided by the inclined surface 143d, and the brake engaging members (204, 208) move to the downstream side in the rotation direction A so as to be away from the drum drive coupling 180. Therefore, a gap is generated between the drum drive coupling 180 and the brake engaging members (204, 208). The engaging portion 143i of the drum coupling 143 enters the gap, so that the driving force receiving portion (side surface) 143b can engage with the drum drive coupling 180 (see FIG. Figure 48 Part (d) Figure 48 Part (e), Figure 49 Part (d), Figure 63 、 Figure 64 、 Figure 68 ).

[0604] The spiral slope 143d also has a function of keeping the brake engaging member (204, 208) away from the drum drive coupling 180 so that the drum drive coupling 180 and the driving force receiving portion 143b can engage with each other.

[0605] The spiral slope (top surface) 143d has not only a portion (downstream guide portion, downstream guide portion, downstream top surface, downstream inclined portion) 143d1 disposed between the braking force receiving portion 143c and the driving force receiving portion 143b but also a portion (upstream guide portion, upstream top surface, upstream inclined portion) 143d2 on the upstream side of the driving force receiving portion 143b (see FIG. Figure 48 Part (a) Figure 47 、 Figure 56 By expanding the area where the inclined surface 143d is provided, the top surface 143d can reliably guide the brake engaging member (204, 208).

[0606] That is, even when the brake engaging member (204, 208) is placed on the upstream side of the driving force receiving portion 143b (see Figure 49 When the braking force receiving portion 143c is moved to the downstream side of the braking force receiving portion 143c by passing through the upstream inclined surface 143d2, the braking engaging member 204, 208 can also be moved to the downstream side of the braking force receiving portion 143c by passing through the upstream inclined surface 143d2 (see Figure 49 (c) and 49(d)).

[0607] In this embodiment, the entire inclined surface 143d is an inclined portion. Both the downstream top surface 143d1 and the upstream top surface 143d2 are descending inclined surfaces that descend toward the downstream in the rotation direction.

[0608] However, it is also possible to make only a part of the inclined surface 143d as the top surface inclined. For example, it is also possible to conceive a structure in which the upstream side of the top surface is inclined as the upstream side inclined surface 143d2 as described above, while the downstream side of the top surface (downstream side top surface 143d2) is not inclined and is a surface perpendicular to the axis of the drum unit (see Figure 81 Part (a) and Figure 81 Part (b)). Figure 81 Part (a) and Figure 81 In the modified example of the drum coupling shown in part (b), the brake engaging member (204, 208) is violently moved by the inclination of the upstream inclined surface (upstream top surface) 143d2, and by utilizing the inertia (momentum) of the movement, it passes through the flat downstream top surface 143d1.

[0609] Furthermore, as a guide portion for guiding the brake engaging member (204, 208), it is conceivable to use only the upstream side top surface (upstream side inclined surface 143d2) and not use the downstream side top surface (downstream side inclined surface 143d1). That is, it is conceivable that there is almost no portion corresponding to the downstream top surface, or the portion is very short compared to the upstream top surface. Figure 74 Describe this structure.

[0610] It is also conceivable to provide a partially ascending portion in the descending helical ramp 143d. Even in this case, if the brake engagement members (204, 208) can be sufficiently guided by the ramp 143d downstream in the rotational direction, the ramp 143d can be considered a descending ramp. That is, even if the ramp is partially ascending, the helical ramp 143d can be considered as a descending ramp as a whole. In other words, the distance from the non-driven end of the cartridge to the helical ramp 143d can be considered to decrease as the helical ramp 143d moves downstream in the rotational direction.

[0611] As such an example, a structure can be conceived in which the rising portion partially provided in the spiral slope 143d is sufficiently shorter than other descending portions, or the rising slope is not too steep, and therefore, the rising portion has less influence on the descending portion.

[0612] In addition, there is a case where the spiral slope 143d has a curved surface shape or is divided into multiple parts. In addition, there is a case where the width of at least a part of the slope 143d is so small that the spiral slope 143d can be regarded as a ridge (edge) rather than a surface. When the drum coupling 143 is observed from the front side, the spiral slope 143d has a fan-shaped shape (spiral shape). However, the shape of the guide portion (top surface, inclined portion) to be provided on the drum coupling 143 is not limited to this shape. For example, instead of using the fan-shaped (spiral) slope 143d, a linearly extended rectangular slope can be used. That is, as the inclined portion (guide portion, top surface) corresponding to the spiral slope 143d, a structure with a changed shape, size, extension direction, etc. can be used. Reference will be made hereinafter to Figure 54 etc. to describe some of these examples.

[0613] The upstream slope (upstream top surface) 143d2 is configured to have a narrower area than the downstream slope (downstream top surface) 143d1 (see FIG. Figure 47 and Figure 56 ). In contrast, the downstream inclined surface 143d1 has a wider area than the upstream inclined surface 143d2.

[0614] Here, the width of each slope is the length measured along the radial direction. Figure 79 As shown, at least a portion of the engaging portion 143i is positioned farther than the guide forming portion 143n in the radial direction of the drum unit relative to the drum unit axis L. In other words, at least a portion of the engaging portion 143i is positioned radially outside the guide forming portion 143n.

[0615] The reason for this size relationship and this arrangement relationship is that the driving force receiving portion 143b of the engaging portion 143i is located near the boundary between the guide portion forming portion 143n and the engaging portion 143i. That is, a portion of the engaging portion 143i extends outward from the guide portion forming portion 143n in the radial direction, forming the driving force receiving portion 143b. As a result, the width of the downstream portion 143d1 of the inclined surface (top surface) 143d is greater than the width of the upstream portion 143d2.

[0616] The driving force receiving portion 143b has an area placed radially outward (away from the axis L) relative to the upstream inclined surface 143d2. In addition, in the axial direction of the drum unit, the driving force receiving portion 143b is provided closer to the non-driving side end portion of the photosensitive drum than the upstream side inclined surface 143d2. Figure 80, a state is shown in which the distance D3 measured from the non-driven side end portion 104b of the photosensitive drum to the driving force receiving portion 143b in the axial direction is shorter than the distance D1 measured from the non-driven side end portion 104b of the photosensitive drum to the upstream top surface 143d2 in the same direction.

[0617] On the contrary, at least a portion of the upstream inclined surface 143d2 is placed farther from the driving force receiving portion 143b in the axial direction than the non-driving side end portion 104b of the photosensitive drum. The upstream inclined surface 143d2 is a free end portion placed closer to the free end of the drum coupling 143 than the driving force receiving portion 143b.

[0618] The distances D1 and D3 can be regarded as the distances in the axial direction from the non-drive side end of the cartridge (ie, the non-drive side cartridge cover 117: see Figure 14 ) is measured from the upstream inclined surface 143d2 and the driving force receiving portion 143b.

[0619] The shutter portion 143d is a blocking portion (stopper) that inhibits (blocks) the movement of the brake engaging member (204, 208) in the axial direction. That is, the shutter portion 143d prevents the brake engaging member (204, 208) from approaching the drum coupling 143 and entering an area where it cannot engage with the braking force receiving portion 143c. Figure 66 、 Figure 49 Part (b) Figure 69 、 Figure 50 Part (a) shows the blocking state.

[0620] In this embodiment, the shutter portion (blocking portion) 143d is located further upstream in the rotation direction than the upstream inclined surface 143d2, and the shutter portion 143d is continuous with the top surface (upstream inclined surface 143d2) of the guide portion forming portion 143n (see FIG. Figure 56 part (d)).

[0621] When the brake engaging members (204, 208) enter the space upstream of the driving force receiving portion 143b or the space downstream of the braking force receiving portion 143c together with the drum drive coupling 180, the brake engaging members (204, 208) cannot engage with the braking force receiving portion 143c. The shutter portion 143g blocks the movement of the brake engaging members (204, 208) to prevent this state from occurring.

[0622] In this embodiment, when the drum unit is viewed from the driving side in the axial direction (see FIG. Figure 47 When the first coupling portion 143s is provided with the shutter portion 143g, the shutter portion 143g is provided so as to cover the space upstream of the driving force receiving portion 143b. In addition, the shutter portion 143g is provided so as to cover the space downstream of the braking force receiving portion 143c.

[0623] Furthermore, the shutter portion 143d has a width sufficient to cover at least a portion of the downstream side portion (downstream side inclined surface 143d1) of the spiral inclined surface (top surface) 143d. Thus, the shutter portion 143d restricts the brake engaging members (204, 208) from preferably entering the space on the upstream side of the driving force receiving portion 143b and the space downstream of the braking force receiving portion 143c together with the drum drive coupling 180.

[0624] On the other hand, the shutter portion 143g is provided to allow the brake engaging member (204, 208) to enter the space on the downstream side of the braking force receiving portion independently of the drum drive coupling 180 (see FIG. Figure 50 Part (d), Figure 49 Part (c), Figure 48 part (c)).

[0625] That is, the brake engaging member (204, 208) contacts the upstream inclined surface 143d2 after passing through the shutter portion 143g, and is guided along the inclined surface 143d toward the space on the downstream side of the braking force receiving portion 143c (see FIG. Figure 49 Part (c) and Figure 50 part (d)).

[0626] That is, when the brake engaging member (204, 208) is able to contact the upstream side portion (upstream side top surface) 143d2 of the inclined surface (top surface) 143d, the shutter portion 143g releases the brake engaging member (204, 208) from the blocking state.

[0627] The shroud portion 143g is adjacent to the upstream slope 143d2 and upstream of the upstream slope 143d2. In this embodiment, the top surface of the shroud portion 143g and the upstream slope 143d2 are continuous, but there may be a case where the shroud portion 143g and the upstream slope 143d2 are adjacent to each other but a gap is formed between them.

[0628] The top surface of the shutter portion 143g is a plane perpendicular to the drum unit axis L, but the shape is not limited to this example. For example, it is conceivable that the top surface of the shutter portion 143g is inclined in the same direction as the upstream inclined surface 143d2. In this case, it is conceivable that the shutter portion 143g forms a portion of the upstream inclined surface 143d2. Alternatively, it is conceivable that a portion of the guide forming portion 143n forms the shutter portion 143g.

[0629] Furthermore, in this embodiment, the coupling 143 includes two of the spiral slopes 143d, two of the shutter portions 143g, two of the driving force receiving portions 143b, and two of the braking force receiving portions 143c. That is, the coupling 143 has a shape symmetrical about its axis and includes two coupling portions 143s and 143r (see FIG. Figure 58 ). The coupling portion 143s and the coupling portion 143r each have a spiral slope (inclined portion) 143d or the like as a top surface. Then, the brake engaging member (204, 208) and the drum driving member 180 engage with the coupling portion 143s and the coupling portion 143r, as shown in FIG. Figure 76 shown in part (a).

[0630] Hereinafter, an example (modified example) of another shape of the coupling 143 will be described.

[0631] The drive transmission unit 203 includes a first brake engaging member 204 and a second brake engaging member 208 as braking force applying members (brake engaging members) that apply a braking force for applying a load to the rotation of the photosensitive drum to the coupling 143. A gap exists between the first brake engaging member and the second brake engaging member 208, and the second brake engaging member, which is disposed radially inward, is slightly flexible so as to move outward to approach the first brake engaging member 204. When the coupling and the drive transmission unit 203 are disengaged from each other, the second brake engaging member 208 can be smoothly disconnected from the coupling 143 by flexing the second brake engaging member 208. For example, the second brake engaging member 208 can be moved above the shutter portion 143g by flexing and can be separated from the coupling 143.

[0632] [Various Modifications of the Coupling and the Box Shown in Embodiment 1]

[0633] Description will be made of a modified example (modified shape) of the drum coupling 143 that partially modifies the above-described embodiment 1. Even when the above-described shutter portion 143g is not provided on the drum coupling 143, it can function appropriately depending on the conditions.

[0634] Figure 52 A perspective view showing the drum coupling 143 in which the shutter portion 143g is not provided, and Figure 53 An expanded view illustrating the joining process is shown.

[0635] Will refer to Figure 52 Describe the shape. Figure 52 143 is a view showing one end of the drum unit, and shows a state in which a coupling member (drum coupling) 143 is mounted to an end portion of the photosensitive drum 104. The drum coupling 143 includes a spiral slope 143d and a push-back surface 143k, which will be described later, but does not have a shutter shape.

[0636] Then, reference will be made to Figure 53 The process of engaging with the drive transmission unit 203 is described.

[0637] Figure 53 The expanded diagram of Figure 48 The drum coupling 143 includes two coupling parts 143s and 143r, but for simplicity of explanation only the coupling part 143s will be described. The description of the coupling part 143s also applies to the coupling part 143r.

[0638] Will describe Figure 53 The case where the phases of the inclination start portion 143f of the drum coupling 143 and the inward protrusion 208e of the second brake engaging member shown in part (a) satisfy the following relationship. That is, the case where the inclination start portion 146f of the drum coupling 143 is on the downstream side in the rotation direction (arrow A) will be described.

[0639] Figure 53 Part (a) shows a state in which the drive transmission surface 180d of the drive transmission unit 203 and the second brake engaging member 208 are close to each other.

[0640] Next, in Figure 53 In part (b), since there is no such shutter portion as described in Example 1, in the drum coupling 143, the drum drive coupling and the second brake engaging member 208 advance into the space between the push-back surface 143k and the spiral slope 143d3.

[0641] Figure 53 Part (c) shows a state where the drive transmission unit 203 has started to rotate in the rotation direction A. When the drum drive coupling 180 and the second brake engaging member 208 rotate, the second brake engaging member 208 moves along the inclined surface in the direction of arrow E by the effect of the inclination angle θ1 of the push-back surface 143k or the effect of the inclination angle θ2 of the second brake engaging member 208. Figure 48 As described above, second brake engaging member 208 may rotate without receiving a rotational load.

[0642] As described above, when the brake engaging member (204, 208) enters the region where it cannot engage with the braking force receiving portion, the push-back surface (push-back portion) 143k applies force to the second brake engaging member 208. Thus, the push-back surface 143k pushes the brake engaging member (204, 208) back toward the inside of the drive transmission unit 203 and moves it in the direction of arrow E.

[0643] However, the second brake engaging member 208 is Figure 43The spring 211 shown in FIG pushes in the M1B direction in the figure, and if the component force of the inclination angle θ2 of the second brake engaging member 208 is smaller than the spring force F1, the second brake engaging member 208 cannot move in the direction of arrow E. The component force varies depending on the load torque of the drum holding unit 108 and the angle of each inclined surface (θ1 or θ2). Taking into account the component force and the friction force, it is preferable to set the magnitude relationship of the force within the range of performing the above-mentioned function.

[0644] Figure 53 Part (d) shows the movement of the second brake engaging member 208 which is no longer subjected to the rotational load. The drive transmission unit 203 has further rotated, and the second brake engaging member 208 is in a state of passing through the tilt start portion 146f of the drum coupling 146. When this state is reached, the second brake engaging member 208 moves in the direction of arrow C, as shown in FIG. Figure 48 The subsequent operations are the same as those described above, and therefore description thereof will be omitted.

[0645] Despite Figure 50 Part (a) to Figure 50 Not shown in part (d) of FIG. 2 , but the first brake engaging member 204 also moves with the second brake engaging member 208 during these processes.

[0646] In the drum coupling 143 shown in Example 1 (see Figure 1 , in part (a)), the brake engaging member (204, 208) is prevented by the shutter portion 143g from entering an area where it cannot engage with the braking force receiving portion. On the other hand, in the drum coupling 143 of this modified example, when the brake engaging member (204, 208) enters an area where the braking force receiving portion 143c cannot engage with the drum drive coupling 180, the brake engaging member (204, 208) is pushed back by the push-back surface (push-back portion) 143k. The push-back surface 143k is an inclined portion inclined in a direction different from the direction of the spiral inclined surface 143. More specifically, the spiral inclined surface 143 is a portion that is inclined toward the non-driven side of the drum unit as the spiral inclined surface moves downstream in the rotational direction, and the push-back surface 143k is a portion of the drum unit that is inclined toward the outside (i.e., away from the non-driven side end portion 104b (see the non-driven side end portion 104b of the photosensitive drum) as the push-back surface moves downstream in the rotational direction A). Figure 80 If the spiral slope 143 is regarded as a descending slope, the push-back surface 143k is an ascending slope. The push-back surface 143k is placed on the upstream side in the rotation direction relative to the spiral slope 143d and is adjacent to the spiral slope 43k.

[0647] The push-back surface 143k is also a guide portion (second guide portion) for guiding the brake engagement member (204, 208) toward the spiral slope 143d. In addition, the push-back surface 134k is a spiral slope (second spiral slope, second inclined portion) having an inclination direction opposite to the inclination direction of the spiral slope 143d.

[0648] Furthermore, another modified shape of the drum coupling 143 will be described. The inclined portion and the top surface (the spiral inclined surface 143d) of the guide portion described in Example 1 are formed into smooth inclined surfaces, and the brake engaging member (204, 208) is guided along such inclined surfaces (see FIG. Figure 56 etc.). However, the drum coupling 143 can function even if the inclined portion has other shapes. Figure 54 An example of this is shown in perspective view in FIG.

[0649] first, Figure 54 The shape shown in part (a) is a reproduction of the shape described in Embodiment 1. A gentle spiral slope 143d is formed from the slope start portion 143f toward the braking force receiving portion 143c.

[0650] on the other hand, Figure 54 Part (b) and Figure 73 The shape of portion (a) is shown as a modified example. The height gradually changes between the inclination start portion 147f and the braking force receiving portion 147c. That is, the top surface (inclined portion) has a stepped portion 147d, and the inclined portion is formed by a plurality of steps. Therefore, the inclined portion (top surface) may not be a spiral slope, but may be a spiral step shape that provides a decreasing inclination in the advancing direction of the second brake engaging member 208.

[0651] The stepped step portion 147d is formed by Figure 73 The second brake engaging member 208 is moved by moving the stepped step portion 147d in the direction of the arrow C in part (a) to perform the operation with Figure 54 The function of the spiral slope 143d in the portion (a) is the same as that of the spiral slope 143d. Although the inclined surface 143d is an inclined portion including a continuous inclined surface, the step portion 147d can be regarded as an inclined portion provided by a stepped structure of a plurality of surfaces.

[0652] If it is difficult to form the spiral slope 143d on the coupling 143 due to limitations in the structure of a mold for manufacturing the coupling 143, a stepped portion 147d may be used instead of the inclined surface 143d.

[0653] At this time, it is preferable that when the step portion 147d as the top surface and the second brake engaging member 208 come into contact with each other, the second brake engaging member 208 is configured to be smoothly guided without being caught by the step portion 147d. For example, it is conceivable to sufficiently narrow the width of each surface of the step portion 147d. In addition, Figure 73 In the portion (a), the top surface (inclined portion, guide portion) is formed into a stepped shape by combining a plurality of surfaces, but the top surface (inclined portion, guide portion) may be formed by combining a plurality of curved surfaces, and a similar function may be performed with such a structure. Similar to the inclined surface 143d, the stepped portion 147d is a guide portion (inclined portion) for guiding the brake engaging member (204, 208) toward the braking force receiving portion by its own inclination.

[0654] In addition, if Figure 54 Part (c) and Figure 73 As shown in part (b), the top surface is divided into an inclined surface (upstream top surface, downstream top surface) 148d1 and an inclined surface (downstream top surface, downstream guide, downstream side) 148d2, with a gap 148g between inclined surface 148d1 and inclined surface 148d2. In this case as well, if the second brake engaging member 208 has a shape that does not cause seizure when it contacts the top surfaces (148d1, 148d2), the top surfaces (148d1, 148d2) can function as guides. This coupling can be used when there are limitations in the structure of the mold used to mold the coupling.

[0655] also, Figure 54 Part (d) and Figure 73 Part (c) shows a modified example in which the shape of each portion of the coupling 143 is formed by ribs. The top surface (inclined surface 149d) includes a surface of a plurality of ribs 149p, and the top surface is divided into a plurality of ribs, and in this case, the same function can also be provided. That is, as Figure 73 As shown in part (c), the guide portion forming portion 149n forming the upstream top surface (upstream guide portion, upstream inclined portion) 149d2 is a protrusion (rib) protruding in the radial direction. Depending on the characteristics of the material used, it can be used when it is necessary to produce a rib without generating a thick portion.

[0656] That is, for Figure 54 Part (a) to Figure 54Each structure of portion (d), each top surface (143d, 147f, 148d1, 148d2, 149d), regardless of its shape, guides the braking force of the brake engaging member (204, 208) toward the braking force receiving portion 143c. In other words, each top surface is a guide portion (inclined portion) for guiding the brake engaging member (204, 208) toward the braking force receiving portion 143c, regardless of its shape. At least a portion of such a top surface (guide portion) is formed by the guide portion forming portion 143n.

[0657] Similar to the top surface, Figure 52 The push-back surface (push-back portion) 143k shown in FIG can have various shapes. For example, the push-back portion (push-back surface) 143k of this modification is a smooth continuous spiral slope, but the push-back portion can be inclined by multiple surfaces or steps. For example, the push-back portion 143k can be composed of two surfaces with different inclinations, such as Figure 48 Part (b) and Figure 56 The push-back portion 143k of the embodiment 1 shown in the portion (d) is the same as that shown in FIG.

[0658] The drum coupling 143 may have the shutter portion 143g or the push-back surface (push-back portion) 143k, or may have both of them. As described above, Figure 48 Part (b) Figure 55 Part (b) and Figure 56 The drum coupling 143 of Example 1 shown in part (d) has a structure in which not only the shutter portion 143g but also the push-back portion 143k is provided. Normally, the drum coupling 143 can prevent the brake engaging members (204, 208) from improperly entering and approaching by the shutter portion 143g, but in the unlikely event that it cannot be prevented, the push-back surface 143k can play a role in pushing the brake engaging members (204, 208) back away from the coupling 143.

[0659] The drum coupling 143 has a push-back surface 143k (see Figure 79 Part (b) and Figure 79 The protrusion shape (push-back portion forming portion, second guide portion forming portion) 143m of the part (c)).

[0660] The engaging portion 143i, the guide forming portion 143n, the protruding shape 143m and the shutter portion 143g (see FIG. Figure 79 ) can be respectively referred to as the first shape portion, the second shape portion, the third shape portion and the fourth shape portion in no particular order.

[0661] refer to Figure 54 Part (e) and Figure 73 In part (d) of the embodiment, a modified example of the braking force receiving portion (second side surface) will be shown.

[0662] Figure 54 Part (a) and Figure 1 Part (a) and Figures 55 to 57 The braking force receiving portion 143c described in the embodiment 1 shown, and Figure 52 and Figure 54 Part (b) to Figure 54 Another modified example shown in part (d) has a shape extending downstream in the rotational direction. This is because the braking force receiving portion 143c has a shape extending toward the downstream side in the rotational direction, which increases the stability of the engagement when it engages with the brake engaging member (204, 208).

[0663] That is, due to this shape, when the braking force receiving portion 143c engages with the brake engaging member (204, 208), a force is generated to attract each other. The braking force receiving portion 143c extends toward the downstream side in the rotational direction. Therefore, when the braking force engaging member (204, 208) contacts the braking force receiving portion 143c, a force is generated to attract the braking force engaging member (204, 208) inward in the axial direction toward the drum coupling 143 or the photosensitive drum 104. As a result, the engagement state between the braking force receiving portion 143c and the braking force engaging member (204, 208) is stable, and the engagement is not easily broken.

[0664] As described above, the brake engagement members (204, 208) are configured to be movable in the axial direction relative to the drum drive coupling 180 (see FIG. Figure 67 and Figure 68 ). However, if the brake engaging members (204, 208) move in the axial direction while the drive transmission unit 203 is driving the drum coupling 143, the engagement state with the braking force receiving portion 143c may be destroyed or become unstable. Therefore, it is preferable that the braking force receiving portion 143c has a shape for stabilizing the engagement state with the brake engaging members (204, 208) to suppress the movement of the brake engaging members (204, 208) in the axial direction when the drum coupling 143 is driven.

[0665] However, when the braking force to be applied to the braking force receiving portion is small, or when the friction coefficient of the braking force receiving portion is high, the engagement between the braking force receiving portion and the brake engaging member (204, 208) tends to be stable. Therefore, it is possible to eliminate the protruding portion of the braking force receiving portion. Figure 54 Part (e) and Figure 73 In the part (d) of Figure 54 Part (e) and Figure 73 In the modified drum coupling shown in (d), the braking force receiving portion 144c does not protrude toward the downstream side in the rotational direction (arrow A).

[0666] On the other hand, even with the braking force receiving portion 144c including such a shape, it is conceivable to devise a means for stabilizing the engagement state with the brake engaging member (204, 208).

[0667] In order to stabilize the engagement between the braking force receiving portion 144c and the brake engaging member, it is also conceivable to attach an elastic member (elastic portion) 144t (such as rubber) to the braking force receiving portion 144c or to form the elastic portion integrally with the braking force receiving portion 144c. By increasing the friction coefficient of the braking force receiving portion 144t or causing the brake engaging member (204, 208) to bite into the elastic portion of the braking force receiving portion 144t, the engagement with the brake engaging member (204, 208) is less likely to be broken, so that the engagement can be stabilized.

[0668] As a method of increasing the friction of the braking force receiving portion 144c, it is conceivable to use an adhesive member (viscous member) instead of using the elastic member 144t. For example, if a double-sided tape (adhesive member) is attached to the surface of the braking force receiving portion 144c, the friction between the braking force receiving portion 144c and the brake engaging member (204, 208) increases due to the viscosity of the double-sided tape (adhesive member). In addition, it is conceivable to increase the friction coefficient of the braking force receiving portion 144c by performing a surface treatment on the braking force receiving portion 144c instead of using the elastic member 144t.

[0669] It is desirable that the helical ramp 143d (see FIG. 143d ) for guiding the brake engagement members (204, 208) Figure 67 ) has a low friction coefficient to achieve smooth guidance. Therefore, even when a material with a high friction coefficient is selected or surface treatment is applied to the braking force receiving portion 144c, it is desirable that this method not be used for the entire coupling, but the use of such a material or such a surface treatment should not be applied to the spiral slope 143d. In other words, it is desirable that the friction coefficient of the braking force receiving portion 144c is higher than the friction coefficient of the spiral slope 143d.

[0670] like Figure 54 Part (a) to Figure 54 As shown in part (d) of the drawing, the elastic portion 144t may be provided on the braking force receiving portion 143c of the drum coupling 143.

[0671] Next, refer to Figure 101 , the preferred arrangement relationship and dimensional relationship of the drum coupling 143 will be described. Figure 101: This is a front view of the drum coupling 143 of Example 1, where θ (theta) 11 is a value indicating the dimension of the engagement portion 143i from the driving force receiving portion 143b to the braking force receiving portion 143c as an angle with the axis of the drum coupling. In other words, it is the angle of the area of ​​the downstream inclined portion 143d1.

[0672] Regarding the upper limit of θ11, it is desirable that θ11 is 90° or less, more preferably 80° or less. Angle θ11 corresponds to the gap generated between the drum drive coupling 180 and the brake engagement member (204, 208) when the drum coupling engages the drive transmission unit 203 (see Figure 64 ). In order to firmly clamp the driving force receiving portion 143b and the braking force receiving portion 143c between the brake engaging member (204, 208) of the main assembly of the apparatus and the drum drive coupling 180, it is desirable that θ11 is 90° or less, more preferably 80° or less.

[0673] On the other hand, regarding the lower limit of θ11, as for the material of the joint portion 143i constituting the driving force receiving portion 143b and the braking force receiving portion 143c, if the strength of the joint portion 143i is increased by using metal, θ11 can be reduced. Although the details will be described below, Figure 74 In the modified example of the drum coupling shown, the thickness of the engagement portion 145i corresponding to the engagement portion 143i is made smaller than that in the present embodiment by forming the drum coupling 143 from metal. Figure 101 ) is preferably a condition for the lower limit of θ11 to be 1°, more preferably 2°, or still more preferably 8° or more. In the present embodiment, θ11 is set to be 30° or more, and θ11 is set to be approximately 35°.

[0674] In order to increase the strength of the driving force receiving portion 143 b and the braking force receiving portion 143 c so that the force can be stably received, the angle θ11 corresponding to the thickness of the engaging portion 143 i is desirably within a certain range.

[0675] When θ11 is converted into length, it becomes the thickness of the engaging portion 143i, that is, the distance measured from the driving force receiving portion 143b to the braking force receiving portion 143c in the rotational direction. The desired range of this distance is 0.3 mm or more, more preferably 1 mm or more.

[0676] In addition, Figure 101In the figure, θ12 indicates the area occupied by the upstream inclined surface (upstream guide portion, upstream inclined surface) 143d2 in angle. Regarding the lower limit of θ12, it is desirable that the value of θ12 is at least half the value of θ11, and the value of θ12 is more preferably not less than the value of θ11. This is because the upstream inclined surface 143d2 needs to have a length in the rotational direction to the extent required to guide the brake engaging member (204, 208) to the braking force receiving portion 143c via the upstream inclined surface 143d2.

[0677] When θ11 is smaller and the inclination angle of the upstream inclined surface 143 d 2 is larger, the lower limit of θ12 can be made smaller.

[0678] As described above, the lower limit of θ12 depends on the value of θ11 and the angle of the upstream inclined surface 143d2. However, when expressed numerically, θ12 is 1° or more, more preferably 2° or more, or even more preferably 8° or more, and even more preferably 30° or more. In this embodiment, θ12 is set to 60° or more.

[0679] The upper limit of θ12 may be relatively large and may exceed 360°. However, preferably, θ12 is 360° or less, more preferably 270° or less, and in this example, 180° or less. Specifically, θ12 is set to approximately 67°.

[0680] In the following we will refer to Figure 102 and Figure 103 A structure in which θ12 is larger than θ12 of the present embodiment will be described.

[0681] Angle θ13 is the sum of θ11 and θ12, and corresponds to the angle occupied by the entire spiral slope 143d. When θ13 is expressed as a numerical value, it is desirable that θ13 is 2° or greater, and more preferably 8° or greater. Furthermore, θ13 is preferably 360° or less, and more preferably 270° or less. In this embodiment, θ13 is set to 180° or less. Specifically, θ13 is set to approximately 102°.

[0682] refer to Figure 74 , another modified shape of the coupling 143 will be described.

[0683] Figure 74 These are perspective views and a front view of the coupling in the modified example as viewed in two viewing directions.

[0684] The modified coupling 143 includes an engaging portion 145i having a driving force receiving portion 143b and a braking force receiving portion 145b, and a guide portion forming portion 145n having a spiral slope 145d. The engaging portion 145i and the guide portion forming portion 145n correspond to the engaging portion 143i and the guide portion forming portion 143n of the coupling 143 shown in Example 1 (see FIG. Figure 79 ), but their shapes are partially different.

[0685] The modified coupling 143 includes a shutter portion 143g that contacts the second brake engaging member 208 (not shown), and the spiral slope 145d is formed by a curved surface. The curved surface has a substantially circular arc shape and is formed so as to connect the braking force receiving portion 145c from the inclination starting point 143f. In this modified example, since the braking force receiving portion 145c does not have a shape that protrudes toward the downstream side in the rotation direction, as shown in FIG. Figure 54 As in the case of portion (e), an elastic member (elastic portion) 145t may be attached to the braking force receiving portion 145c.

[0686] The modification ( Figure 74 ) corresponds to the spiral slope 145d in Example 1 ( Figure 57 )'s top surface of the upstream slope 143d2.

[0687] On the other hand, in this modification ( Figure 74 ), the top surface (upper portion) 145e ( Figure 74 Part (b)) corresponds to Example 1 ( Figure 57 )'s downstream slope 143d1, but it is not as inclined as the downstream side slope 143d1.

[0688] That is, the top surface 145e disposed downstream is connected to the top surface (the spiral slope 145d) disposed upstream, but the inclination angles of the surfaces thereof are different at the boundary. The top surface 145e and the spiral slope 145d are not smoothly connected.

[0689] Furthermore, since the distance between the driving force receiving portion 143b and the braking force receiving portion 145c is short, the length of the top surface 145e measured in the rotation direction is smaller (shorter) than Figure 57 The length of the downstream inclined surface 143d1 in the embodiment of the present invention is as follows. In addition, as described above, the top surface 145e is not inclined. In this modification, it can be considered that the top surface 145e does not serve as a guide portion.

[0690] However, even with this structure, the helical slope 145d as the guide portion (inclined portion) can guide the brake engaging member (204, 208) toward the braking force receiving portion 145c.

[0691] The flat surface 145h is adjacent to the upstream of the spiral slope 145d, and the spiral slope 145d and the flat surface 145h are connected to each other. The flat surface 145h can be inclined in the same direction as the spiral slope 145d to form a part of the spiral slope 145d. In addition, the modified drum coupling can have the shutter portion 143g of the push-back surface 143k described in Example 1 or another modification of Example 1 (see Figure 1 、 Figure 52 wait).

[0692] In addition, the shape of the drum coupling can also be selected for design reasons. Figure 1 The shape of the shaft portion 143j is shown. For example, Figure 75 The shape of a modified example of the drum coupling is shown. Figure 75 In the example shown, the diameter of the shaft portion 146j is the same as the diameter of the photosensitive drum 104. The shaft portion 146j is rotatably supported by the drive side cartridge cover member 116 (see FIG. Figure 15 ). For example, the shaft end surface 146s can be used to perform position restriction in the direction of the arrow MB1. In this way, the shape of the shaft portion 146j can be appropriately selected according to the relationship with the peripheral portion and the manufacturing method.

[0693] Another modification of the drum coupling 143 is Figure 76 Part (b) Figure 76 Part (c), Figure 78 Part (a) Figure 78 Part (b) Figure 78 Part (c) and Figure 78 These figures show drum couplings in which the two coupling parts 143s and 143r have different shapes. Figure 76 Parts (b) and (c) are expanded views of the coupling 143, and Figure 76 In part (c) of the drawing, the drum drive coupling 180 and the brake engaging member 208 provided in the apparatus main assembly side are also shown in an expanded view. Figure 78 Part (a) and Figure 78 Part (b) is a perspective view of the drum coupling 143. In addition, Figure 78 Part (c) and Figure 78 Part (d) shows the engaged state of the brake engagement members (204, 208) and the drum drive coupling relative to the drum coupling 143.

[0694] In the coupling 143 shown in these figures, the engaging portion 143i of one coupling portion 143s is not provided with a braking force receiving portion 143c, but includes only a driving force receiving portion 143b. That is, the side surface 143y provided on the engaging portion 143i of the coupling portion 143s does not engage with the brake engaging member (204, 208). On the other hand, the engaging portion 143i of the other coupling portion 143r is only provided with a braking force receiving portion 143c and is not provided with a driving force receiving portion 143b. The side surface 143x of the engaging portion 143i of the coupling portion 143r does not engage with the drum drive coupling 180.

[0695] Another example of an asymmetric coupling 143 is Figure 76 This coupling portion 143s is an example in which the coupling portion 143s does not have any side surface corresponding to the driving force receiving portion 143c.

[0696] exist Figure 76 Part (b) Figure 76 Part (c), Figure 78 Part (a) Figure 78 Part (b) Figure 78 Part (c) and Figure 7 The modified example of the coupling 143 shown in FIG receives the driving force at only one place and receives the braking force at only one place. Therefore, in order to stably receive the driving force and the braking force by the drum coupling, it is preferable to improve the fitting accuracy between the circular hole portion 143a and the positioning boss 180i of the drum drive coupling 180 (see FIG. Figure 51 ). That is, it is preferable to reduce the gap generated therebetween, thereby improving the positional accuracy of the drum coupling 143 relative to the drive transmission unit 203, so as to stably and reliably engage the drive transmission unit 203 and the drum coupling 143.

[0697] also, Figure 77 Another modification of the drum coupling including one driving force receiving portion and one braking force receiving portion is shown. Figure 77 The drum coupling 143 shown has only one upstream side slope 143d2, only one downstream side slope 143d1, only one shutter portion 143g, only one driving force receiving portion 143b, only one braking force receiving portion 143c, and only one extrusion surface 143k. Figure 77 Part (a) is a perspective view of the drum coupling, and Figure 77 Part (b) is its front view.

[0698] In such Figure 77In the modified example of the drum coupling 143 shown, any portion of the inclined surface 143d, shutter portion 143g, driving force receiving portion 143b, braking force receiving portion 143c and extrusion surface 143k can be placed at one or more 180° positions (axisymmetric).

[0699] For example, Figure 96 As shown, Figure 77 The shutter portion 143g of the drum coupling 143 shown may be moved to the 180° symmetrical area S143g, or the extrusion surface 143k may be moved to the symmetrical area S143k.

[0700] This is because the drum drive coupling 180 and the brake engagement members (204, 208) both have 180° symmetrical shapes.

[0701] Therefore, regardless of which of the two 180° symmetrical positions is where one spiral slope 143d is provided, the slope 143d can act on the entire brake engaging member (204, 208). Similarly, the extrusion surface 143k can be placed at either of the two positions 180° symmetrical with respect to each other. This applies not only to the shutter portion 143g and the extrusion surface 143k, but also to the braking force receiving portion 143c.

[0702] Furthermore, the drum drive coupling 180 can be engaged with the driving force receiving portion 143b regardless of whether the driving force receiving portion 143b is placed at either of the two 180° symmetrical positions.

[0703] The drum drive coupling 180 has two drive transmission surfaces 180d, but the two drive transmission surfaces 180d move integrally ( Figure 45 In addition, the brake engaging members (204, 208) each have two coupling engaging portions 204b and 208b, and all of these coupling engaging portions move integrally (see Figure 45 part (b)).

[0704] As another modification in which the shape of the drum coupling 143 is formed asymmetrically as described above, there is also the following structure. That is, one coupling part 143s has an engaging portion 143i but does not have a guide forming portion 143n, and the other coupling part 143r has a guide forming portion 143n but does not have an engaging portion 143i. This structure is conceivable. An example of this structure is shown in FIG. Figure 97 are shown in parts (a) and (b). Figure 97 Part (a) is a perspective view of a modified example of the drum coupling, Figure 97 Part (b) is its front view.

[0705] In the modified example of the drum coupling shown in these figures, the guide forming portion 343n and the engaging portion 343i have one. The guide forming portion 343n forms a spiral slope (guide portion, top surface, inclined portion) 343d2. The engaging portion 343i forms a driving force receiving portion 343b and a spiral slope (guide portion, top surface, inclined portion) 343d1. The guide forming portion 343n and the engaging portion 343i are located on opposite sides of the axis L. In addition, in this modification, the braking force receiving portion 343b is not arranged at the engaging portion 343i, but is arranged at the downstream end portion in the rotation direction of the guide forming portion 343n. That is, the engaging portion 343i engages with the driving force applying member (drum drive coupling) 180, but does not engage with the braking force applying member (brake engaging member 204, 208).

[0706] Figure 99 Parts (a), (b) and (c) show the engagement process of the drum coupling and the brake engagement member (204, 208) of this modified example in this order. For ease of explanation, the drum drive coupling 180 of the drive transmission unit 203 is not shown.

[0707] like Figure 99 As shown in part (a) of , when the second brake engaging member 208 contacts the inclined surface 343d2 of the guide portion forming portion 343n, the second brake engaging member 208 starts to move toward the downstream side in the rotational direction and approaching the photosensitive drum 104 in the axial direction.

[0708] like Figure 99 As shown in part (b) of the figure, when the second brake engaging member 208 reaches the vicinity of the end of the upstream inclined surface 343d2, the first brake engaging member 204 contacts the inclined surface 343d1, which is the top surface of the engaging portion 343i. Thereafter, the brake engaging members (204, 208) continue to rotate, and the free end of the first brake engaging member 204 enters the space downstream of the engaging portion 343i, as shown in FIG. Figure 99 The first brake engaging member 204 reaches a position where it can engage with the braking force receiving portion 343c (see FIG. Figure 97 part (b)).

[0709] As mentioned above, also in Figure 97 and Figure 99 In the modified drum coupling shown, any part thereof can be moved to a 180° symmetrical position. For example, Figure 98 As shown in part (a), the coupling portion 343i and the driving force receiving portion 343b can be moved to positions S343i and S343b, which are 180° symmetrical positions, respectively. The coupling in which the coupling portion 343i moves to S343i is similar to Figure 77 A modified example of the drum coupling shown in . In contrast, when Figure 77 When a portion of the drum coupling shown in FIG is moved to a 180° symmetrical position, the shape is similar to Figure 97 The shape of the modified drum coupling is shown in .

[0710] like Figure 98 As shown in part (a) of FIG, in this modification, when the engaging portion 343i is imaginarily placed at the 180° symmetrical position S343i, the inclined surface 343d2 is adjacent to the imaginary engaging portion S343i. The upstream side portion 343d2a of the inclined surface 343d2 extends from upstream to downstream in the rotation direction toward the imaginary engaging portion S343i and the imaginary driving force receiving portion S343b.

[0711] Figure 98 Part (b) shows angles θ41 , θ42 , θ51 , and θ52 with respect to the size of each portion in this modification.

[0712] Angle θ41 is the angle of the area where the engaging portion 343i is arranged. θ42 is the angle of the area occupied by the spiral slope 343d2 of the guide forming portion 343n. θ51 is the angle indicating the area from S343b, where the driving force receiving portion 343b is imaginarily arranged at a 180° symmetrical position, to the braking force receiving portion 343c. θ52 is the angle of the area occupied by the portion 343d2a of the spiral slope 343d2 located on the upstream side in the rotational direction, from the position S343b where the driving force receiving portion is imaginarily arranged.

[0713] From the viewpoint of ensuring the strength of the driving force receiving portion 343 b , the angle θ41 is preferably not less than 1°, further preferably not less than 2°, and even more preferably not less than 8°.

[0714] The angle θ51 corresponds to the angle of the gap between the brake engagement members (204, 208) and the drum drive coupling 180. Therefore, it is desirable not to exceed 80° as described above.

[0715] Furthermore, since θ51 is larger than θ41, θ51 is preferably 1° or more, further preferably 2° or more, and even more preferably 8° or more. Furthermore, it is desirable that θ41 is 80° or less.

[0716] Angle θ52 corresponds to Figure 101 The angle of θ12 in the figure is θ52, and the preferred range of θ52 is the same as that of θ12. In addition, since θ42 is the angle corresponding to Figure 101 The angle of θ13 in θ42 is the same as that of θ13.

[0717] In addition, Figure 100 Part (a) and Figure 100 Another modification of the asymmetrical drum coupling is shown in part (b). The structure is such that the upstream inclined surface 143d2 (see Figure 58 The upstream inclined surface 143d2 is divided into an upstream portion 143d2a and a downstream portion 143d2b. The joint portion 143i is adjacent to the downstream portion 143d2b of the upstream inclined surface 143d2.

[0718] exist Figure 100 The dimensional relationship in this modified example is shown in part (b). Angle θ21 is the angle of the engaging portion 143i and corresponds to Figure 101 The angle θ11 in θ21 is preferably the same as the angle θ11. θ22b is an angle of a range occupied by the downstream portion 143d2b of the upstream side inclined surface 143d2, and θ22b is an angle occupied by the upstream portion 143d2a of the upstream side inclined surface 143d2.

[0719] The area where the downstream portion 143d2b of the upstream inclined surface 143d2 is imaginarily moved to a position symmetrical at 180° is area S143d2b. At this time, the angle of the area occupied by the imaginary area S143d2b and the upstream portion 143d2a is θ32. Since θ32 corresponds to Figure 101 The angle θ12 in θ32 is equal to the preferred angle range of θ12.

[0720] The range of appropriate angles of θ22a and θ22b is also based on θ12.

[0721] Furthermore, further modifications of the drum coupling will be described. The spiral slope 143d and the upstream slope 143d2 as the guide portion and the upstream guide portion may be changed to be smaller than the drum coupling of Example 1 ( Figure 1 etc.) are long. This example is Figure 102 and Figure 103 In the drum coupling shown in these figures, the spiral inclined surface 443d2 corresponding to the upstream inclined surface 143d2 extends to more than 360 degrees. That is, the spiral inclined surface 443d2 extends over one full circle.

[0722] Engaging portion 443i, corresponding to engaging portion 143i of Example 1, is provided separately from inclined surface 443d2. Engaging portion 443i includes braking force receiving portion 443c1 and driving force receiving portion 443b. Braking force receiving portion 443c2 is also provided near the end of spiral inclined surface 443d2. Braking force receiving portion 443c1 and braking force receiving portion 443c2 are arranged at positions 180° symmetrical.

[0723] exist Figure 103 Part (a) Figure 103 Part (b) and Figure 103 In the part (c) of FIG. 1 , the engagement process of the drum coupling and the brake engagement member in this modified example is shown in chronological order. For ease of explanation, the drum drive coupling 180 is not shown.

[0724] like Figure 103 As shown, the brake engaging members (204, 208) rotate one or more turns by being guided by the spiral bevel 443d2. In this way, the length of the spiral bevel 443d2, which serves as a guide portion and an inclined portion, can be increased to more than 360°. However, if the spiral bevel 443d2 is longer, it may be possible that the time required for the brake engaging members (204, 208) to pass through the spiral bevel 443d2 is longer, or the speed of the brake engaging members (204, 208) on the spiral bevel 443d2 is slower. To solve this problem, when the drive transmission unit 203 and the coupling 143 are engaged with each other, measures may need to be taken to ensure that the brake engaging members (204, 208) have enough time to pass through the spiral bevel 443d2, for example, by reducing the rotation speed of the drive transmission unit 203.

[0725] In order to smoothly engage the drive transmission unit 203 and the drum coupling 143 with each other while rotating the drive transmission unit 203 at high speed, it is desirable to shorten the time required for the brake engagement member (204, 208) to pass through the spiral slope 443d2. From this viewpoint, it is further preferred that the length of the spiral slope (inclined portion, guide portion) 443d2 is 360° or less, and further preferably, the length is 270° or less.

[0726] As described above, a modified example in which the drum coupling of Embodiment 1 is changed to an asymmetric shape can also be used.

[0727] However, if Figure 1 and Figure 58 As in the drum coupling 143 of the first embodiment shown, it is further preferred that the coupling 143 include a driving force receiving portion 143b and a braking force receiving portion 143c at two locations 180° apart. This is because the engagement state between the drive transmission unit 203 and the coupling 143 and the transmission state of the driving force are then stabilized. The coupling 143 receives the driving force at two symmetrically arranged points and also receives the braking force at two symmetrically arranged points. Therefore, it becomes easier to maintain the balance of the forces applied to the coupling 143.

[0728] In addition, in the drum coupling 143 (see Figure 1), each shaped portion of the coupling (engagement portion, guide forming portion, shutter portion, etc.) has a specific arrangement relationship. However, it is also conceivable to change these arrangement relationships by making any part of the coupling 143 movable.

[0729] As an example of such a structure, Figures 104 to 106 14 shows a structure in which the engaging portion 243i is movable relative to other portions of the drum coupling 143, and specifically, a structure in which the engaging portion 243i can advance and retract in the radial direction. Figure 105 As shown, the drum coupling 143 is provided with two openings 243p, and the engaging portion 243i is partially exposed from the interior of the drum coupling through these openings 243p.

[0730] like Figure 105 As shown in part (a), the two engaging portions 243i are supported by the guide portion 199a of the support member 199 provided inside the drum coupling. In addition, the engaging portion 243i is constructed to be movable in the radial direction along the guide portion 199a, but is urged inwardly in the radial direction by the tension spring 200.

[0731] Therefore, when the box is not in use, as Figure 104 Part (a) and Figure 104 As shown in part (c), the two engaging portions 243i are retracted into the interior of the drum coupling. On the other hand, when the cartridge is mounted to the main assembly of the imaging device, the positioning boss 180i enters the interior of the drum coupling and contacts the engaging portions 243i, as shown in FIG. Figure 106 In addition, when the positioning boss 180i enters the interior of the drum coupling 143, the engaging portion 243i is pushed outward in the radial direction by the positioning boss 180i. Figure 104 Part (b) and Figure 104 As shown in part (d) of , a portion of the engaging portion 243i advances toward the outside of the drum coupling 143.

[0732] In this state, both side portions of the engaging portion 243i, ie, the driving force receiving portion 243b and the braking force receiving portion 243c are exposed, and the driving force and the braking force can be received from the image forming apparatus main assembly, respectively.

[0733] As described above, the arrangement relationship and shape of the coupling 143 are not constant and may vary or change. For example, it is conceivable that when the cartridge is not in use, the drum coupling portion, which is susceptible to external impact, is retracted to be protected.

[0734] When a portion of the coupling 143 is movable, a state in which the coupling is actually used, that is, a state of the coupling 143 when the cartridge and the drum unit are mounted to the main assembly of the image forming apparatus and the coupling 143 is engaged with the drive transmission unit 203, can be regarded as a reference state. In this reference state, the shape of the coupling 143 and the arrangement relationship of each portion can be configured to satisfy the desired conditions as described above.

[0735] also, Figure 107 and Figure 108 Another modified example of the drum coupling 143 is shown, which is configured so that a portion of the drum coupling 143 is deformed and moved. Figure 105 ), the engaging portion 243i is configured to move in the radial direction, but in this modified example, the engaging portion 643i is configured to move in the axial direction. Figure 107 Part (a) shows a state where the engaging portion 643i is retracted into the interior of the drum coupling, and Figure 107 Part (b) shows the engaging portion 643i moving toward the outside of the drum coupling and away from the photosensitive drum. Figure 107 Part (c) is an exploded perspective view of the drum unit in this modified example.

[0736] Figure 108 Parts 108 (a) and 108 (b) show cross-sectional views of the drum unit. Figure 108 Part (a) shows the state before the drum unit is mounted to the apparatus main assembly, and Figure 108 Part (b) shows a state after the drum unit is mounted thereon.

[0737] When the drum unit is mounted to the main assembly of the apparatus, the positioning boss 180i provided on the drive transmission unit comes into contact with the working member of the drum coupling. Figure 108 As shown in part (b) of the drawing, the operating member 698 moves inward in the axial direction (on the right side in the drawing). As the operating member 698 moves, the interlocking member 698 is pushed outward in the radial direction inside the drum coupling. As the interlocking member 698 moves outward in the radial direction, the engaging portion 643i is pressed outward in the radial direction by the interlocking member 698. Thus, the state changes from the state retracted to the inside of the drum unit ( Figure 107 Part (a) and Figure 108 The portion (a)) is changed to the bonding portion 643i partially exposed to the outside ( Figure 107 sections (b) and 108(b)).

[0738] When a portion of the drum coupling is movably provided in this manner, the direction of movement may be a radial direction or an axial direction.A portion of the drum coupling may be movable in both radial and axial directions, or may be movable in a rotational direction.

[0739] Next, we will refer to Figure 109 and Figure 110 Another modification of the drum coupling is described. Similar to the above two modifications, the drum coupling 1043 of this modification is also constructed so that a part thereof deforms and moves.

[0740] Figure 109 Part (a) is an exploded perspective view of the drum unit of this modified example. Figure 109 Part (b) shows a state in which the engaging portion 1043i of the drum coupling has advanced toward the outside of the drum unit, and part (c) shows a state in which the engaging portion 1043i is partially retracted toward the inside.

[0741] In this modification, before the drum unit is mounted on the apparatus main assembly, the engaging portion 1043i is in the position shown in FIG. Figure 109 On the other hand, after the drum unit is mounted to the main assembly of the device, the engaging portion 1043i becomes as shown in the protruding (advanced) state shown in part (b). Figure 109 The retracted state is shown in part (c).

[0742] Figure 110 Part (a) and Figure 110 Part (b) shows a cross-sectional view of the drum unit. Figure 110 (a) shows the state before the drum unit is completely mounted on the apparatus main assembly, and part (b) shows the state after the mounting is completed.

[0743] like Figure 109 As shown in part (a) of the drum coupling, the engaging member 1043 is provided inside the drum coupling so as to be movable in the axial direction. The engaging member 1043 is pushed (pressed) to the outside in the axial direction by the pressurizing coil spring 1020 provided inside the drum coupling 143, and the engaging portion 1043i as a part of the engaging member 1043 is exposed to the outside of the drum coupling 143.

[0744] Then, the engaging member 1043 has an acting portion 1043p on its rotation axis. Figure 110 When mounted to the main assembly of the apparatus as shown in part (b), the engaging member 1043 and the engaging portion 1043i are retracted inwardly in the axial direction by the acting portion 1043p pushed by the positioning boss 180i.

[0745] In the three modified examples described above, the acting portion capable of receiving an action from the outside of the cartridge is provided inside the coupling 143, and the acting portion is operated by the positioning boss 180i to change the shape of the coupling 143. However, it is also conceivable that the acting portion for changing the shape of the coupling 143 is provided somewhere other than the inside of the coupling 143.

[0746] As described above, the shape and form of the coupling may be selected based on design factors for arrangement, considerations of manufacturing a mold for coupling production, and the purpose of protecting the coupling.

[0747] In addition, in each of the three modified examples of the drum coupling described above, the engaging portion provided with the driving force receiving portion and the braking force receiving portion moves relative to the other portions. However, portions such as the spiral ramp or the shutter portion may be movable relative to the other portions.

[0748] In addition, the above-mentioned cartridge 100 includes a photosensitive drum and a developing roller, but the structure of the cartridge 100 is not limited to this structure. For example, the cartridge 100 may include a photosensitive drum but not a developing roller. As an example of such a structure, a cartridge 100 may include only the drum holding unit 108 (see FIG. Figure 19 ) structure.

[0749] Furthermore, in Embodiment 1 and its various modified examples, the drum coupling 143 is placed near one end (the end on the drive side) of the photosensitive drum 104, and it is press-fitted into the photosensitive drum 104. Therefore, the driving force can be transmitted from the drum coupling 143 to the end of the photosensitive drum 104. However, the method of connecting the drum coupling 143 and the photosensitive drum 104 is not limited to press-fitting. Furthermore, in the above-mentioned examples, the drum coupling 143 and the photosensitive drum 104 are integrated to form the drum unit 103, but the drum coupling 143 and the photosensitive drum 104 may be separated from each other without constituting a drum unit.

[0750] That is, if the drum coupling 143 is operably connected to the photosensitive drum 104, that is, if it is connected in a drive-transmittable manner, another connection method may be adopted, and the coupling 143 and the photosensitive drum 104 may not constitute the same unit.

[0751] For example, one or more relay members may be interposed between the coupling 143 and the photosensitive drum 104. In this case, it can be considered that the drum coupling is indirectly connected to the drive side end of the photosensitive drum 104 through the relay member. The drum coupling 143 operates the photosensitive drum 104 through the relay member by rotating itself.

[0752] For example, it is conceivable to mount a gear to the end of the photosensitive drum 104 and also form a gear portion on the outer peripheral surface of the drum coupling 143. In this manner, the gear of the coupling 143 and the gear of the photosensitive drum 104 can be directly meshed with each other, or an additional idler gear can be interposed between the two gears to transmit the driving force from the drum coupling 143 to the photosensitive drum 104.

[0753] In addition to using the gears as the relay member, a method of connecting a drive transmission belt to the drum coupling 143 and the photosensitive drum 104 to use it as the relay member can also be conceived.

[0754] It is also conceivable to connect the end of the photosensitive drum 104 on the drive side and the drum coupling 143 by using an oldham coupling as a relay member. In this case, the drum unit 103 can be regarded as a unit including the photosensitive drum 104, the oldham coupling (relay member) and the drum coupling 143.

[0755] As described above, the connection method between the photosensitive drum 104 and the drum coupling 143 can be direct connection or indirect connection. In addition, the photosensitive drum 104 and the drum coupling 143 can be combined to form the drum unit 103, or the photosensitive drum 104 and the drum coupling 143 can be separately provided in the box and can not constitute a unit.

[0756] However, if the coupling 143 and the photosensitive drum 104 form a drum unit 103 that can rotate as a whole, or if the coupling 143 is directly connected to the end of the photosensitive drum 104, the drive (rotation) of the coupling 143 can be more accurately transmitted to the photosensitive drum 104, and therefore, it is more preferable to do so.

[0757] In this embodiment, the axis of the drum coupling 143 is aligned with the axis of the photosensitive drum 104. That is, the drum coupling 143 and the photosensitive drum 104 are aligned along the same rotation axis L (see FIG. Figure 1 ). However, when the drum coupling 143 and the photosensitive drum 104 are indirectly connected, the positions of the axes may be different from each other.

[0758] In any case, by engaging the coupling 143 with the drive transmission unit 203 provided in the main assembly of the apparatus, the cartridge can be driven stably.

[0759] An example in which the structure of the box and the like is changed will be further described below with reference to Embodiment 2.

[0760] <<Example 2>>

[0761] <Overall Structure of Imaging Apparatus 800>

[0762] refer to Figure 82 ...

Claims

1. A cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus, the main assembly comprising a driving force applying member and a braking force applying member, the cartridge comprising: shell; a photosensitive drum rotatably supported by the housing; a coupling connected to the photosensitive drum so as to enable drive transmission, The coupling comprises: a driving force receiving portion for receiving a driving force for rotating the coupling by engaging with the driving force applying member, and a braking force receiving portion for receiving a braking force for applying a load resisting rotation of the coupling by engaging with the braking force applying member, and A guide portion is used to move the braking force applying member relative to the driving force applying member.

Images