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 an invention patent application with an 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 a 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.), their multifunction printers, etc.

[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 an electrophotographic forming process, 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 image forming apparatus 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 image forming apparatuses.

[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 cassette varies depending on the construction of the cassette.

[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 provided for moving 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 that is 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 provided for moving the braking force applying member relative to the driving force applying member.

[0027] Another example of the box according to the present application is a box 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 end portion and the second end portion of the housing; and

[0030] a coupling connected to the photosensitive drum to enable drive transmission, the coupling being disposed 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 shaped portion has a first side portion at a position upstream of the rotational movement direction and a second side portion at a position downstream of 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 distant 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 disposed 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 at a position 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 the downstream in the 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 the 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 distant portion of the first shaped portion.

[0044] Another example of the box according to the present application is a box 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 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 the 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 located farther from the axis of the drum unit in the radial direction of the coupling than a distant portion of the guide portion.

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

[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 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 the downstream in the circumferential direction, 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,

[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 for receiving a braking force for applying a load resisting rotation of the coupling by engaging with the braking force applying member.

[0068] Another example of a 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 for receiving a braking force for applying a load resisting rotation of the coupling by engagement 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, an example of the electrophotographic image forming apparatus according to the present application includes any one of the above-mentioned 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 device.

[0080] Figure 3 is a cross-sectional view of a 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 is a detailed view of a portion of the pallet.

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

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

[0087] Fig.10 It is a side view (partial cross-sectional view) of the process box.

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

[0089] Fig.12 is a perspective view of a development separation control unit.

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

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

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

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

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

[0095] Fig.18 It is a view of the force applying member R itself.

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

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

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

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

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

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

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

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

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

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

[0106] Fig.29 It is a view of the force applying member L itself.

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

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

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

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

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

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

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

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

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

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

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

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

[0119] Fig.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] Fig.43 is an exploded perspective view of the drive transmission unit 203 .

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

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

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

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

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

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

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

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

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

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

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

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

[0133] Fig.56 is a diagram of a drum unit showing the drum coupling.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

[0151] Fig.74 : are a perspective view and a front view showing a modified example of the drum coupling.

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

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

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

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

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

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

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

[0159] Fig.82 is a schematic cross-sectional view of an imaging device.

[0160] Fig.83 is a schematic cross-sectional view of a process cartridge.

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

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

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

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

[0165] Fig.88 2 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] Fig.89 is a schematic perspective view of another form of drum coupling 770.

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

[0168] Fig.91 701 is a schematic cross-sectional view showing an operation of mounting the cartridge 701 to the image forming apparatus main assembly 800.

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

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

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

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

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

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

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

[0176] Fig.99 is a perspective view showing an engaged state of the coupling and the brake engagement member.

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

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

[0179] Fig.102 are the front view, perspective view and side view of the coupling.

[0180] Fig.103 is a perspective view showing an engaged state of the coupling and the brake engagement member.

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

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

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

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

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

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

[0187] Fig.110 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 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 drawings.

[0191] In the following embodiments, as the image forming apparatus, an image forming apparatus to which and from which four process cartridges can be attached and detached is shown.

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

[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 2is a schematic cross-sectional view of the imaging device M. In addition, Figure 3 is a cross-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 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 called the drive side, and the left side is called the non-drive side.

[0198] Furthermore, when the imaging apparatus M is viewed from the front side, the upper side is the upper surface and the lower side is the lower surface. Figure 2 is a cross-sectional view of the imaging device M as 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 processing box 100 is a side on which a drum coupling (photosensitive member coupling) described below is arranged in the axial direction of the photosensitive drum. In addition, the driving side of the processing box 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 rotation axis of the photosensitive drum, which will be described below. Similarly, the axial direction of the developing roller is a direction parallel to the rotation axis of the developing roller, which will be described below. In the present embodiment, the axis of the photosensitive drum and the axis of the developing roller are substantially parallel, and therefore, the axial direction of the photosensitive drum and the axial direction of the developing roller are considered to be substantially the same.

[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 boxes 100 (100Y, 100M, 100C, 100K) has the same electrophotographic process mechanism, and the color of the developer (hereinafter referred to as the toner) is different. The rotational driving force is transmitted from the drive output portion (details will be described below) of the image forming apparatus main assembly 170 to the first to fourth process boxes 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, 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 acting on the photosensitive drum 104. In addition, 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 an 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 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, so that the surface of the photosensitive drum 104 is exposed 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 driving 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 boxes 100 (100Y, 100M, 100C, 100K) contacts the upper surface of the transfer belt 12a. The contact portion is a 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 Figure 3 The machine is driven to rotate in the direction of arrow A in FIG.

[0219] The transfer belt 12a is still in the forward direction ( Figure 2 The photosensitive drum 104 is driven to rotate in the same direction as the rotation of the photosensitive drum (in the direction of arrow C) at a speed corresponding to the speed of the photosensitive drum 104.

[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 to a predetermined polarity and potential in each process cartridge. The laser scanner unit 14 scans and exposes the surface of each photosensitive drum 104 with a laser beam U according to an image signal of each color.

[0221] Thus, 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 rotationally driven at a predetermined speed. More specifically, the developing roller 106 is in contact with the photosensitive drum 104, and the toner moves from the developing roller 106 to the latent image of the photosensitive drum 104, so that the latent image is developed into a toner image. In the present embodiment, a contact developing method is adopted, and the developing roller 106 and the photosensitive drum 104 are in contact with each other. However, a non-contact developing method may be adopted in which the toner jumps from the developing roller 106 to the photosensitive drum 104 through a small gap between the developing roller 106 and the photosensitive drum 104.

[0222] By 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 box 100Y. Then, the toner image is primary transferred to the transfer belt 12a. A portion of the photosensitive drum 104 is exposed to the outside of the box and contacts the transfer belt 12a. At the contact portion, the toner image on the surface of the photosensitive drum 104 is transferred to 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 which 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 Fig.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 opened and the process cartridge 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, wherein the front door 11 is opened and the process cartridge 100 has 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 state shown. Figure 7 Part (b) is in Figure 4 A partial detailed view of the tray 171 as viewed from the non-drive side in the state.

[0232] like Figure 4 and Figure 5 As shown, the tray 171 can move in the arrow X1 direction (pushing direction) and the arrow X2 direction (pulling direction) relative to the imaging device main assembly 170. That is, the tray 171 is configured to be retractable from the imaging device main assembly 170 and insertable into the imaging device main assembly 170, and the tray 171 is configured 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 opened and the photosensitive drum 104 and the transfer belt 12a separated from each other ( 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 cover member 116 and the immovable side cover member 117, as shown in FIG. Figure 7Then, the process cartridge is moved in the main assembly 170 of the image forming apparatus as the tray 171 moves while being placed in the mounting portion 171a. At this time, during the movement, a gap is maintained between the transfer belt 12a and the photosensitive drum 104. The tray 171 can carry the process cartridge 100 into the main assembly 170 of the image forming apparatus without the photosensitive drum 104 contacting the transfer belt 12a (details will be described below).

[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 main assembly 170 of the image forming apparatus 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. Figure 7 The illustrated cover member 116 is defined by arcuate portions 116VR1 and 116VR2 contacting the 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 projection 171KL are provided at positions (non-driven side) opposite to 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 projection 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 The position shown.

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

[0243] In the present embodiment, the positioning portions 171VR and 171V also serve as reinforcing members for maintaining rigidity during the pulling-out operation of the tray 171, and thus, a metal plate is used, but the present invention is not limited thereto.

[0244] [Cartridge Pressing Mechanism]

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

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

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

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

[0249] For the cartridge pressing mechanism (190, 191), the storage element pressing unit 190 operates on the non-driven side, and the cartridge pressing unit 191 operates on the driven side. 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 shown descend in the direction of arrow Z2.

[0251] The storage element pressing unit 190 is provided with a main assembly side electrical contact (not shown) that is mainly in contact with an electrical contact 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 the arrow Z2 in association with the operation of closing the front door 11, and functions to press the processing cartridge 100 against the above-mentioned positioning portion 171VL.

[0256] Further, although the details will be described below, the cartridge pressing mechanism (190, 191) also plays a role of pressing 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 Fig. 9 and Fig.10 (For better illustration, the tray 171 is omitted), the drive transmission mechanism of the main assembly in this embodiment will be described.

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

[0260] Fig.10 1 is a side view of the process cartridge 100 as viewed from the driving side.

[0261] like Fig.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 ( Fig. 9 In the state of part (b), the drive unit drives the processing cartridge 100 and transmits the driving force to the main assembly side drum drive coupling and the main assembly side developing drive coupling 185 of the processing cartridge 100, which project in the direction of arrow Y1 through a link mechanism (not shown).

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

[0264] By retracting each coupling from the insertion / removal trajectory (X1 direction, X2 direction) of the processing cartridge, the 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 engages with the drum coupling (coupling member, cartridge side coupling) 143. At the same time, the developing drive coupling 185 on the main assembly side engages with the developing coupling portion 32a. Thus, the drive is transmitted to the processing cartridge 100. The drive transmission to the processing cartridge 100 is not limited to the above structure, and a mechanism that only inputs the drive to the drum coupling and transmits the drive to the developing roller can be provided.

[0266] [Intermediate transfer unit structure]

[0267] Next, referring to Fig. 9 , the intermediate transfer unit 12 of the main assembly of the imaging device 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 through a link mechanism (not shown), and moves to a position for imaging operation (the photosensitive drum 104 and the intermediate transfer belt 12a are in contact with each other).

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

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

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

[0272] The intermediate transfer belt 12a is driven by receiving a force from a gear (not shown) provided coaxially with the PV1. Therefore, by setting the above-mentioned position PV1 as the rotation center, the intermediate transfer unit 12 can be raised and lowered without moving the center of the gear. By doing so, there is no need to move the center of the gear, and the position of the gear can be maintained with high accuracy.

[0273] With the above structure, when the processing box 100 is set in the tray 171, the photosensitive drum 104 and the intermediate transfer belt 12a do not rub against each other when the tray 11 is inserted or removed, 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 , Fig.11 and Fig.12 , the separation mechanism of the main assembly of the image forming apparatus in this embodiment will be described.

[0276] Fig.11 1 is a sectional view of the image forming apparatus M taken along the driving side end of the process cartridge 100 . Fig.12 It is a perspective view of the development separation control unit viewed obliquely from above.

[0277] In this embodiment, the developing separation control unit 195 controls the separation contact operation of the developing unit 109 relative to the photosensitive drum 104 by engaging with a part of the developing unit 109. Figure 8 As shown, the developing separation control unit 195 is disposed 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] Further, 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 developing separation control unit 195R on the driving side and a developing separation control unit 195L on the non-driving side.

[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 image forming apparatus. However, the separation control members 196R are configured to be movable in the W41 and W42 directions by a control mechanism (not shown). The detailed structure will be described below.

[0282] The developing 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 developing separation control unit 195L is always fixed to the main assembly of the image forming apparatus. However, the separation control members 196L are configured to be movable in the W41 and W42 directions by a control mechanism (not shown). The detailed structure will be described below.

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

[0284] Therefore, for the overlap 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 part of the developing unit (in this embodiment, the biasing member 152) needs to protrude. Details will be described below.

[0285] When the developing 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 complexity of the drive train.

[0286] In this embodiment, a method is adopted in which the developing separation control unit 195 is fixed to the main assembly 170 of the image forming apparatus, and a part of the developing unit 109 (the biasing member 152) protrudes downward (Z2) in the main assembly 170 of the image forming apparatus, and one of the reasons for this arrangement is to solve this problem. In addition, the mechanism for causing the biasing member 152 to protrude utilizes the mechanism of the above-described storage element pressing unit 190 and the cartridge pressing unit, and therefore, the above problems do not exist and an 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 , Fig.13 and Fig.14 , the structure of the process box will be described.

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

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

[0292] The process cartridge 100 includes a photosensitive drum 104 (4Y, 4M, 4C, 4K) and a process device acting on the photosensitive drum 104. The cartridge 100 includes a charging roller 105 as a process device, which is a charging device (charging member) for charging the photosensitive drum 104. In addition, the cartridge 100 includes a developing roller 106 as another process device, which is a developing device (developing member) for developing a 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, etc.) 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 Fig.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 Figure 1 Part (a), details of which 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 Fig.13 and Fig.14 As shown in FIG. 1 , a drum coupling 143 for transmitting a 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 component side drum drive coupling 180 (see FIG. 1 ) as a drum drive output unit of the main component 170 of the imaging device. Fig. 9 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. In addition, 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 box cover 116, and the drum flange 142 is supported by a shaft fixed to the non-drive side box cover 117. Thus, the drum unit 103 is rotatably supported in the box. That is, the end of the photosensitive drum 104 is rotatably supported by the end of the housing of the box (that is, the box covers 116 and 117) through 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] In the opposite sides of the drum unit 103 in the longitudinal direction (axial direction), the side on which the coupling 143 is provided is the driving side, and the side on which the drum flange 142 is placed is the non-driving side. That is, in the opposite ends of the photosensitive drum 104 in the axial direction, the coupling 143 is fixed near the end on the driving side, and the drum flange 142 is fixed near the end on the side opposite to the driving side. In 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. Fig.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. Fig.10 and Fig.19 is a diagram showing the drive side of the cartridge. Fig.16 is a diagram showing the non-driving side of the cartridge.

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

[0304] [Developer unit structure]

[0305] like Figure 3 and Fig.13 As shown, the developing unit 109 includes a developing roller 106, a toner feeding roller (toner supplying 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 containing portion 129 for containing 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 below, and holds a developing scraper 130 for regulating the layer thickness of the toner on the circumferential surface of the developing roller 106.

[0307] The developing scraper 130 is formed by mounting an elastic member 130b, which is a plate-shaped metal having a thickness of about 0.1 mm, on a supporting member 130a, which is a metal material having an L-shaped cross section, by welding or the like. The developing scraper 130 is mounted to the developing frame 125 with fixing screws 130c at two locations, one near one end in the longitudinal direction and the other near the other end. The developing roller 106 includes a core metal 106c and a rubber portion 106d.

[0308] The developing roller 106 is rotatably supported by a driving side bearing 126 and a non-driving side bearing 127 respectively mounted to opposite ends in the longitudinal direction of the developing frame 125. The developing frame 125, the driving side bearing 126, and the non-driving 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 Fig.13 and Fig.14 As shown in FIG. 1 , 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. Fig. 9 ) are engaged, and the driving force of the driving motor (not shown) of the imaging device main component 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 The toner feed roller 107 rotates in the direction of the arrow D. Similarly, the driving force received by the developing input coupling portion 32a also rotates the toner feed roller 107 to supply the developing roller 106 with toner.

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

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

[0314] refer to Fig.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 a driving side cover member 116 and a non-driving side cover member 117 provided at respective ends of the process cartridge 100 in the longitudinal direction.

[0315] A driving-side cartridge cover member 116 disposed on one side (driving side) of the processing cartridge 100 in the longitudinal direction is provided with a developing unit support hole 116a for swingably (movable) supporting the developing unit. Similarly, a non-driving-side cartridge cover member 117 disposed on the other side (non-driving side) of the processing cartridge 100 in the longitudinal direction is provided with a developing unit support 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, an outer diameter portion of a 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, an outer diameter portion of a 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, opposite end portions in the longitudinal direction of the photosensitive drum 104 are respectively fitted into the drum support holes 116b of the driving-side cartridge cover member 116 and the drum support holes 117b of the non-driving-side cartridge cover member 117. Then, the driving-side cartridge cover member 116 and the non-driving-side cartridge cover member are fixed to a drum frame 115 of the drum holding unit 108 with screws or an adhesive (not shown). Thus, the developing unit 109 is rotatably supported by the driving-side cartridge cover member 116 and the non-driving-side cartridge cover member 117. The developing unit 109 can move (rotate) relative to the drum holding unit 108, and the developing roller 106 can move relative to the photosensitive drum through this movement. At the time of imaging, the developing roller 106 can be placed at a position acting on the photosensitive drum 104.

[0318] The drum frame 115 and the cover members 116 and 117 are part of a cartridge frame (housing). More specifically, they are frames 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] In addition, one of the frames (115, 116, 117) of the drum holding unit 108 and the frames (125, 126, 127) of the developing unit can be referred to as a first frame (first housing), and the other can be referred to as a second frame (second housing), etc. In addition, the frames (115, 116, 117) of the drum holding unit 108 and the frames (125, 126, 127) of the developing unit can be collectively referred to as the frame of the cartridge (housing of the cartridge) without any special distinction therebetween.

[0320] Fig.14 A state 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 is shown.

[0321] The axis connecting the center of the developing unit support hole 116a of the driving side box cover member 116 and the center of the developing unit support hole 117a of the non-moving side box cover member 117 is called 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 device 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. Fig.15 An assembly perspective view showing the driving side of the developing unit 109 including the separation contact mechanism 150R. Fig.16 An assembled perspective view of a developing unit including a separation contact mechanism 150L on the non-driving side is shown. Regarding the separation contact mechanism, details of the separation contact mechanism 150R on the driving side will be described first, and then the separation 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 restricting member, an urging member 152L as a pressing member, and a tension spring 153 .

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

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

[0329] Fig.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. Fig.17Parts (b) and (c) are perspective views of the separation holding member 151R itself. Fig.17 Part (d) is in Fig.17 A view of the separation retaining member 151R observed in the direction of arrow Z2 in part (a) (vertically upward in the imaging state). The separation retaining member 151R includes an annular support receiving portion 151Ra, and includes a separation retaining 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 retaining portion 151Rb has an arc-shaped separation retaining surface 151Rc, which has a center on the separation retaining member swing axis H and is inclined at an angle θ1 relative to a line HA parallel to the separation retaining member swing axis H. The angle θ1 is selected to satisfy equation (1).

[0330] 0°≦θ1≦45°...(1)

[0331] In addition, the separation holding member 151R has a second regulated surface 151Rk adjacent to the separation holding surface 151Rc. In addition, the separation holding member 151R is provided with a second pressed portion 151Rd protruding beyond the support receiving portion 151Ra on Z2, and an arc-shaped 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 Fig.18 , the force applying member 152R will be described in detail.

[0335] Fig.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 Fig.18 B and Fig.18 C is a perspective view of the urging member 152R itself.

[0336] The force 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 force member 152R has a protruding portion 152Rh formed on the downstream side of the arrow LH2 direction of the elliptical support receiving portion 152Ra. The elliptical support receiving portion 152Ra and the protruding portion 152Rh are connected by a main body portion 152Rb. On the other hand, the force member 152R includes a pressed portion 152Re protruding in the arrow LH1 direction and substantially perpendicular to the arrow LH1 direction, and has an arc-shaped pressed surface 152Rf on the downstream side of the arrow LH1 direction, 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 be opposite to each other in a direction substantially perpendicular to the arrow LH2 direction at the end portion in the arrow LH2 direction. The first force receiving portion 152Rk and the second force receiving portion 152Rn have a first force receiving surface 152Rm and a second force receiving surface 152Rp extending in the HB direction and having an arc shape, respectively. In addition, the protruding portion 152Rh has a locking portion 152Rt and a spring hook portion 152Rs protruding in the HL direction, and the locking portion 152Rt has a locking surface 152Ru facing the same direction as the first force receiving surface 152Rp.

[0338] In addition, the force applying member 152R is a part of the main body portion 152Rb and is arranged on the upstream side of the second force receiving portion 152Rn in the arrow LH2 direction, and has a first pressing surface 152Rq facing the same direction as the second force receiving surface 152Rp. In addition, the force applying member 152R has a second pressing surface 152Rr that is perpendicular to the first accommodation limiting surface 152Rv and is opposite 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 Fig.10 and Figures 15 to 19 , the assembly of the separation contact mechanism will be described. Fig.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 Fig.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 protruding in the direction of the swing axis K.

[0343] The outer diameter of the first support portion 128c cooperates 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. Fig.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 developing cover member 128 is the urging member swing axis HC. Fig.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 128m with the separation retaining member 151R.

[0345] Fig.101 is a cross-sectional view taken along line CS, in which a part of the drive side cartridge cover member 116 and a part 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 it about the separation holding member swing axis H in the direction of the arrow B1 in the figure and for urging the urging member 152R in the direction of the arrow B3.

[0346] The arrow B3 direction is in the elliptical direction LH2 (see FIG. Fig.18 ) in a direction substantially parallel to the direction in which the tension spring 153 is assembled. 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. Fig.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 to apply a pushing 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 to apply a pushing 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 holding member 151R and the spring hook portion 152Rs of the force holding 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 line GS and the line 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. Thus, the force applying member 152R is urged to rotate around the force applying member swing axis HC in the direction of the arrow BA.

[0348] 0°≦θ2≦90°...(2)

[0349] like Fig.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 matched, and in addition, the supporting portion 126a of the driving side bearing 126 and the cylindrical portion (not shown) of the developing drive input gear are matched. 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 installation positions of the separation holding member 151R and the urging member 152R are as follows. Fig.15 As shown, in the direction of the swing axis K, the separation and holding member 151R is arranged on the side (outer side in the longitudinal direction) where the driving side box cover member 116 is arranged, with the developer cover member 128 interposed therebetween. The force member 152R is arranged on the side (inner side in the longitudinal direction) where the developer drive input gear 13 is arranged. However, its position is not limited to this, and the positions of the separation and holding member 151R and the force member 152R can be interchanged, and the separation and holding member 151R and the force member 152R can be arranged in 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 can be interchanged.

[0351] The developing cover member 128 is fixed to the developing frame 125 through the driving side bearing 126 to form the developing unit 109. Fig.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, Fig. 20 is a cross-sectional view, wherein, for ease of explanation, Fig.10 The periphery of the separation holding portion 151R in is enlarged and a portion of the tension spring 153 and the separation holding member 151R are partially omitted by the local 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 pushing 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 accommodating position (reference position) of the force member 152R. In addition, the separation holding member 151R rotates around the swing axis H of the separation holding member in the B1 direction by the pushing 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, and the rotation is thereby stopped. This position is referred to as the separation holding position (limiting position) of the separation holding member 151R.

[0353] also, Fig.21 is a diagram in which, for ease of explanation, Fig.10The periphery of the separation holding portion 151R in [the relevant context] is enlarged and the tension spring 153 is omitted. Here, consider the case where the processing cartridge 100 including the separation contact mechanism 150R according to the present embodiment drops in the JA direction of [a certain reference] when the processing cartridge 100 is being transported. Fig.21 At this time, the separation holding member 151R receives a force that rotates 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 prevention surface 151Rn of the separation holding member 151R does not contact the locking surface 152Ru of the biasing 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, it is possible to prevent the separation holding member 151R from rotating in the B2 direction during transportation, and it is possible to prevent the separated state between the photosensitive drum 104 and the developing unit 109 from being damaged.

[0354] In the present embodiment, the tension spring 153 is mentioned as a pressing device for pressing the separation holding member 151R to the separation holding position and for pressing the biasing member 152R to the accommodation position, but the pressing device is not limited to this example. For example, a torsion coil spring, a leaf spring, etc. can be used as the pressing device for pressing the biasing member 152R to the accommodation position and pressing the separation holding member 151R to the separation holding position. In addition, the material of the pressing device can be a metal, a mold, etc. that has elasticity and can press the separation holding member 151R and the biasing member 152R.

[0355] As described above, the developing unit 109 provided with the separation contact mechanism 150R is integrally coupled to the drum holding unit 108 by the drive-side cartridge lid member 116 as described above ( Fig.19 in the state).

[0356] Fig. 22 is a view seen in the direction of arrow J in part (a) of Fig.19 . As Fig.15 shown, the drive-side cartridge lid 116 of the present embodiment has a contact surface 116c. As Fig. 22 shown, the contact surface 116c is inclined at an inclination angle θ3 with respect 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. In addition, as Fig.15 and Fig.19As shown, when the drive side box cover member 116 is assembled to the developing unit 109 and the drum retaining unit 108, the contact surface 116c faces the separation retaining surface 151Rc of the separation retaining member 151R placed at the separation retaining position. The contact surface 116c is brought into contact with the separation retaining 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 retaining 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 retaining member 151R by the gap P1 is referred to as the separation position (retracted position) of the developing unit 109 (see Fig.42 part (a)).

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

[0358] Fig.42 1 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. Fig.42 Part (a) of FIG. 1 shows a state in which the developing unit 109 is separated from the photosensitive drum 104 . Fig.42 Part (b) shows a state in which the developing unit 109 is in contact with the photosensitive drum 104.

[0359] First, in a state where the separation holding member 151R is placed at the separation holding position and the developing unit 109 is located at the separation position, the pressed portion 152Re of the force member 152R is pushed in the ZA direction. As a result, the protruding portion 152Rh of the force 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 force member 152R through the tension spring 153 as described above. Therefore, when the second force receiving portion 152Rn is pressed in the direction of the arrow W42, the force member 152R rotates around the force member swing axis HC in the direction of the arrow BB to rotate the separation holding member 151R in the direction of the arrow B2. When the separation holding member 151R rotates in the direction of the arrow B2, the separation holding surface 151Rc is separated from the contact surface 116c, whereby the developing unit 109 can rotate from the separation position around the swing axis K in the direction of the arrow V2. 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) ( Fig.42116d of the driving side cartridge cover 116, so that the separation holding member 151R is maintained at the separation release position.

[0360] Furthermore, the driving side bearing 126 has a first pressure receiving surface 126c which is a surface perpendicular to the swing axis K. Since the driving side bearing 126 is fixed to the developing unit 109, the developing unit 109 presses the first force receiving portion 152Rk of the force applying member 152R in the direction of the arrow 41 in 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 126c, the developing unit 109 rotates in the direction of the arrow V1 about the swing axis K to move to the separation position ( Fig.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 given by Fig.42 Part (a) and Fig.42 , as shown by arrow W41 in part (b). 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 separation 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 Fig.12 , Fig.23 and Fig.24 The engaging operation between the separation contact mechanism 150R of the process cartridge 100 and the developing separation control unit 195 of the image forming apparatus main assembly 170 is described when the process cartridge 100 is mounted to the image forming apparatus main assembly 170. For convenience of explanation, these figures are sectional views in which a part of the developing cover member 128 and a part of the driving side cartridge cover member 116 are omitted along partial sectional lines CS1 and CS2, respectively.

[0364] Fig.23 1 is a view 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 main assembly 170 of the imaging device of the present embodiment includes a separation control member 196R corresponding to each of the process cartridges 100 described above. When the process cartridges 100 are placed at the first inner position and the second inner position, the separation control member 196R is arranged on the lower side of the main assembly 170 of the imaging device below the separation holding 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 main assembly 170 of the imaging device. 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 usually 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 contacts 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 ( Fig.24 This position is referred to as the protruding position of the urging member 152R. When this operation is completed, Fig.24As shown, a gap T4 is formed between the first force application surface 196Ra of the separation control member 196R and the first force receiving surface 152Rp of the force application member 152R, and a gap T3 is formed between the second force application surface 196Rb and the second force receiving surface 152Rp. Then, it is placed at a second mounting position where the separation control member 196R does not act on the force application member 152R. This position of the separation control member 196R is referred to as the original position. At this time, the arrangement is such that the first force receiving surface 152Rp of the force application member 152R and the first force application 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 application member 152R and the second force application surface 196Rb of the separation control member 196R partially overlap in the W1 and W2 directions.

[0367] [Contact operation of the developing unit]

[0368] Next, refer to Figure 24 to Figure 26 , the contact operation between the photosensitive drum 104 and the developing roller 106 by the separation contact mechanism 150R will be described in detail. For ease 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 Fig.24 The developing roller 106 is rotated 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. Fig.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 through the developing pressure spring 134, as will be described below. Even in this case, the separation holding surface 151Rc of the separation holding member 151R contacts the contact surface 116c of the driving side cartridge cover member 116, and therefore, the 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 Fig.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 application surface 196Rb of the separation control member 196R and the second force receiving surface 152Rp of the force application member 152R contact each other, so that the force application member 152R rotates in the BB direction around the swing axis HC of the force application member 152R. In addition, as the force application member 152R further rotates, the separation holding member 151R rotates in the B2 direction, and at the same time, the second pressing surface 152Rr of the force application member 152R contacts the second pressure receiving surface 151Re of the separation holding member 151R. Then, the separation holding member 151R is rotated by the force application member 152R to the separation allowing position where the separation holding surface 151Rc and the contact surface 116c are separated from each other. Here, the separation holding member 151R is used to move Fig.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 way, 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 below, and moves to the point where the developing roller 106 and the photosensitive drum 104 are in contact with each other ( Fig.25 At this time, the separation retaining member 151R pushed in the direction of arrow B1 by the tension spring 153 is maintained in the separation allowing position through the second regulated surface 151Rk contacting 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 ( Fig.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. Fig.25 Status to Fig.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 force application member 152R can rotate and the separation holding member 151R can move from the separation holding position to the separation allowing position. Thus, the developing unit 109 can move from the separation position to the contact position where the developing roller 9 and the photosensitive drum 104 contact each other. Fig.26The position of the separation control member 196R is Fig.24 The same as in.

[0374] [Developing unit separation operation]

[0375] Next, refer to Fig.26 and Fig. 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 Fig.26 152Rb 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 ( Fig. 27 151R, the developing unit 109 rotates around the swing axis K in the direction of the arrow V1 from the contact position. Here, the pressed surface 152Rf of the force applying member 152R has an arc shape, and the center of the arc is placed 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 force applying member 152R from the box pressing unit 121 points to 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 retaining member 151R, the second regulated surface 151Rk of the separation retaining member 151R and the second limiting surface 116d of the driving side box cover member 116 are separated from each other, and the separation retaining member 151R rotates 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 contacts 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. Fig. 27 Here, 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. Fig. 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 from the second position to the original 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 main assembly 170 of the image forming apparatus and the developing pressure spring 134 to be described below, and the separation holding surface 151Rc contacts the contact surface 116c. That is, the developing unit 109 is in a state where 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 where they are separated by the gap P1 ( Fig.24 and Fig.42 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 ( Fig.24 status in ). From Fig. 27 Status to Fig.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, so that the separation holding member 151R moves 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 becomes a state in which the separation holding member 151R maintains the separation position.

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

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

[0381] Fig.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 Fig.28 B and Fig.28 C is a perspective view of the separation holding member 151L itself. The separation holding member 151L includes an annular support receiving portion 151La, and includes a separation holding portion 151Lb protruding from the support receiving portion 151La in the radial direction of the support receiving portion 151La. The free end of the separation holding portion 151Lb has an arcuate separation holding surface 151Lc extending around the separation holding member swing axis H.

[0382] In addition, the separation and holding member 151L has a second regulated surface 151Lk adjacent to the separation and holding surface 151Lc. In addition, the separation and 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 and 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 Fig.29 , the force applying member 152L will be described in detail.

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

[0387] The force 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 an arrow LH, the upward direction is depicted by an arrow LH1, and the downward direction is depicted by an arrow LH2. In addition, the direction in which the elliptical support receiving portion 152La extends is depicted by HD. The force 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 the 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 member 152L includes a pushed portion 152Le protruding in the direction of the arrow LH1 and in a direction substantially perpendicular to the direction of the arrow LH1, and an arc-shaped pressure-receiving surface 152Lf is provided on the downstream side in the direction of the arrow LH1 and a push-limiting surface 152Lg is also provided 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, which are arranged to be opposite to each other in a direction substantially perpendicular to the arrow LH2 direction at the end portion in the arrow LH2 direction. The first force receiving portion 152Lk and the second force receiving portion 152Ln have a first force receiving surface 152Lm and a second force receiving surface 152Lp extending in the HD direction and having an arc shape, respectively. In addition, the protruding portion 152Lh is provided with a spring hook portion 152Ls and a locking portion 152Lt protruding in the HB direction, and the locking portion 152Lt is provided with a locking surface 152Lu facing the same direction as the second force receiving surface 152Lp.

[0389] In addition, 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 arrow LH2 direction, and has a first pressing surface 152Lq facing the same direction as the second force receiving surface 152Lp. In addition, 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 arrow LH2 direction, 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 to 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.

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

[0392] Next, refer to Fig.16 and Figure 29 to Figure 35 , the assembly of the separation mechanism will be described. Fig.30 1 is a perspective view of the process cartridge 100 viewed from the drive side after the separation holding member is assembled with the process cartridge 100. As described above, Fig.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 supporting hole portion 117a of the non-driving side cartridge cover member 117. Thus, the developing unit 109 is supported 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 supporting portion 127b and a second supporting portion 127e protruding in the direction of the swing axis K.

[0393] The outer diameter of the first support portion 127b cooperates 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-driving side bearing 127 is the separation holding member swing axis H. The non-driving side bearing 127 includes a first retaining portion 127c protruding in the direction of the separation holding member swing axis H. Fig.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 as to be rotatable and movable 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. Fig.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 127f in contact with the separation retaining member 151L.

[0395] Fig.31 : 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 retaining member 151L. It is a view taken along the line CS, in which a part of the non-driving side box cover member 117 is omitted, so that the matching part between the elliptical support receiving portion 151La of the force applying member 152L and the cylindrical portion 127e of the non-driving side bearing 127 can be seen. Here, the separation contact mechanism 150L is provided with a tension spring 153, which is used to push the separation retaining member 151L to rotate it around the separation retaining 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. 2 ) of the elliptical support receiving portion 152La of the force applying member 152L. Fig.29 ) in a direction substantially parallel to the direction in which the tension spring 153 is assembled. 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. Fig.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 to apply 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 to apply 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 holding member 151L and the spring hook portion 152Ls of the force holding 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. Thus, the force applying member 152L is urged to rotate around the force applying member swing axis HE in the BA direction in the figure.

[0397] 0°≦θ3≦90°...(3)

[0398] In this embodiment, the installation positions of the separation holding member 151L and the force applying member 152L are as follows. Fig.29 As shown, in the direction of the swing axis K, the separation holding member 151L and the force member 152L are arranged on the side (longitudinal outer side) where the non-driving side cartridge cover member 117 of the non-driving 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 (inner side in the longitudinal direction) of the non-driving side bearing 127, and the separation holding member 151L and the force member 152L may be provided with the non-driving side bearing 127 interposed therebetween. In addition, the arrangement order of the separation holding member 151L and the force 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. Fig.16 As shown, in the fixing method in the present 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 employed.

[0400] Fig.32 Part (a) and Fig.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 are partially omitted by the local section line CS. Fig.32 Part (a) and Fig.32 In part (b), Fig.31 The urging member swing axis line HE of the urging member 152L and the portion around the separation holding portion 151L are shown to be 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. Fig.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 accommodation 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, Fig.33 yes Fig.31 The periphery of the separation holding portion 151L in the embodiment is enlarged for 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. Fig.33 In the case where the separation holding member 151L falls in the direction of the arrow JA. At this time, the separation holding member 151L receives a force to rotate in the direction of the arrow B2 due to its own weight around the separation holding swing axis H. When the separation holding member 151L starts to rotate in the direction of the arrow B2, for the above reasons, 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 the arrow B2. Thus, the separation holding member 151L can be prevented from rotating in the direction of the 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 the present embodiment, the tension spring 153 is mentioned as a pushing device for pushing the separation holding member 151L to the separation holding position and the force member 152L to the accommodation position, but the pushing device is limited to this example. For example, a torsion coil spring, a leaf spring, etc. can be used as a pushing device for pushing the force member 152L to the accommodation position and the separation holding member 151L to the separation holding position. In addition, the material of the pushing device can be a metal, a mold, etc. that has elasticity and can push the separation holding member 151L and the force member 152L.

[0404] As described above, the developing unit 109 provided with the separation contact mechanism 150L is integrally connected to the drum holding unit 108 via the non-driving side cartridge cover member 117 as described above ( Fig.30 status in ). Fig.16 As shown in FIG. 1 , the non-driving side cartridge cover 117 of the present 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. Fig.16 and Fig.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 a spring hook portion 117e of the non-driving side cartridge cover member 117 and a 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 a gap P1 by the separation holding member 151L is referred to as a separated position (retracted position) of the developing unit 109 (see Fig.35 part (a)).

[0406] Here, reference Fig.35 , the separation state and the contact state of the process cartridge 100 will be described in detail. Fig.35 1 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. Fig.35 Part (a) shows a state in which the developing unit is separated from the photosensitive drum 104. Fig.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 ( Fig.34152Ln is pressed in the direction of arrow W42, the force member 152L rotates around the force member swing axis HE in the direction of arrow BD to rotate the separation and holding member 151L in the direction of arrow B5. When the separation and holding member 151L rotates in the direction of 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 around the swing axis K in the direction of 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) ( Fig.34 117d of the driving side cartridge cover 116). 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 the 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, the developing unit 109 presses the first force receiving portion 152Lk of the force applying member 152L in the direction of the arrow 41 while the developing unit 109 is in the contact position. Then, by the first pressing surface 152Lq contacting the first pressure receiving surface 127h, the developing unit rotates around the swing axis K in the direction of the arrow V1 and moves to the separation position ( Fig.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 Fig.34 Part (a) and Fig.34Indicated by arrow W41 in part (b). In addition, the direction opposite to arrow W41 is indicated by arrow W42, and the directions of arrow W41 and arrow 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 arrow W41. In addition, the first pressure receiving surface 127h and the second force receiving surface 151Le of the separation retaining 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 separation 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 Fig.35 and Fig.36 The engagement between the separation contact mechanism 150R of the process cartridge 100 and the developing separation control unit of the image forming apparatus main assembly 170 is described when the process cartridge 100 is mounted on the image forming apparatus main assembly 170. For ease of explanation, these figures are cross-sectional views in which a portion of the developing cover member 128 and a portion of the non-driving side cartridge cover member 117 are partially omitted by a partial section line CS, respectively. Fig.35 1 is a view 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 main component 170 of the imaging device of the present embodiment has a separation control member 196L corresponding to the corresponding process box 100 as described above. When the process box 100 is placed at the first internal position and the second internal position, the separation control member 196L is arranged on the lower surface side of the main component 170 of the imaging device 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 box 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 main component 170 of the imaging device. 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 usually 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 contacts 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 a protruding position ( 152Lh ) where the process cartridge 100 protrudes downward in the Z2 direction. Fig.36 When the operation is completed, such as Fig.36 As shown, a gap T4 is formed between the first force application surface 196La of the separation control member 196L and the first force receiving surface 152Lp of the force application member 152L, and a gap T3 is formed between the second force receiving surface 152Lp and the second force application surface 196Lb. Then, it is placed at a second mounting position where the separation control member 196L does not act on the force application member 152L. This position of the separation control member 196L is referred to as the original position. At this time, the first force receiving surface 152Lp of the force application member 152L and the first force application 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 application member 152L and the second force application surface 196Lb of the separation control member 196L are arranged to partially overlap in the W1 and W2 directions.

[0415] [Contact operation of the developing unit]

[0416] Next, refer to Figure 36 to Figure 38, the operation of making the photosensitive drum 104 and the developing roller contact each other by the separation contact mechanism 150L will be described in detail. For the convenience of explanation, 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 127 are partially omitted in the partial section line CS, respectively. It is a cross-sectional view.

[0417] As described above, the developer input coupling 32 is Fig.24 The developing unit 109 receives a driving force in the direction of the arrow V2 from the image forming apparatus main assembly 170, so that the developing roller 106 rotates. 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, due to the urging force of the above-mentioned developing pressure spring 134, the developing unit 109 also receives an urging force in the direction of the arrow V2.

[0418] like Fig.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 through 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 ( Fig.36 status).

[0419] The separation control member 196L of this embodiment is configured to Fig.36 152Lb and the second force receiving surface 152Lp of the force member 152L are in contact with each other, and the force member 152L rotates in the BD direction around the force member swing axis HD. In addition, as the force member 152L rotates, the separation holding member 151L rotates in the B5 direction, and the second pressing surface 152Lr of the force member 152L contacts the second pressure receiving surface 151Le of the separation holding member 151L. Then, the separation holding member 151L is rotated by the force member 152L to the separation allowing position where the separation holding surface 151Lc 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. Fig.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 way, 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 ( Fig.37 At this time, the separation retaining member 151 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 ( Fig.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. Fig.37 Status to Fig.38 The state transitions are executed without delay. Fig.38 The position of the separation control member 196L is Fig.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 force applying member 152L rotates to move the separation holding member 151L from the separation holding position to the separation allowing position. Thus, 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 contact each other.

[0422] [Developing unit separation operation]

[0423] Next, we will refer to Fig.38 and Fig.39 The operation of moving the developing unit 109 from the contact position to the separation position is described in detail. Fig.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 the partial section line CS, respectively.

[0424] The separation control member 196L in this embodiment is configured to Fig.38152Lb and the first force receiving surface 152Lm of the force member 152L are in contact with each other, and the force member 152L rotates along the arrow BC centered on the force member swing axis HD. Since the first pressing surface 152Lq of the force member 152L is in 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 around the swing axis K ( Fig.39 Here, the pressed surface 152Lf of the force member 152L has an arc shape, and the center of the arc is placed 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 force member 152L from the box pressing unit 121 faces 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 the 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 arrow B4 direction by the urging force of the tension spring 153. Thus, the separation holding member 151L rotates until the second pressed surface 151Le contacts the second pressing surface 152LR of the force member 152L, and the position is moved to the separation holding position by 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. Fig.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 from the second position to the original 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 ( Fig.36 and Fig.34As a result, 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 ( Fig.36 status in ). From Fig.39 Status to Fig.36 The state transitions are executed without delay.

[0426] As described above, in the structure of this embodiment, the separation holding member 151L moves from the separation allowing position to the separation holding position by the movement of the separation control member 196L from the home position to the second position. And, by the return of the separation control member 196L from the second position to the home position, the developing unit 109 is changed to a state in which the separation position is maintained by the separation holding member 151L.

[0427] So far, the operation of the separation mechanism placed on the driving side of the process cartridge 100 and the operation of the separation mechanism placed on the non-driving side have been described separately, but in the present embodiment, they operate in association 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 Figure 23 to Figure 27 and Figure 35 to Figure 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 arranged on the driving side is placed at the separation holding position and the timing at which the separation holding member 151L arranged on the non-driving side is placed at the separation holding position are substantially the same, and the timing at which the separation holding member 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 driving side and the non-driving 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 locate 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 non-matching 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 respectively provided with the same separation contact mechanism, and they operate substantially at the same time. 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, the change in the separation amount in the longitudinal direction can be suppressed.

[0429] Furthermore, according to the present embodiment, by moving the separation control member 196R (L) in one direction (the arrow W41 and W42 directions) between the home position, the first position, and the second position, the contact state and the separation state between the developing roller 106 and the photosensitive member can be controlled. Therefore, the developing roller 106 can be brought into contact with the photosensitive drum 104 only when an image is formed, and the developing roller 4 can be maintained in a state of being separated from the photosensitive drum 104 when an image is not formed. Therefore, even if image formation is not performed for a long period of time, the developing roller 106 and the photosensitive drum 104 are not deformed, and a stable image can be formed.

[0430] Furthermore, according to the present embodiment, the urging member 152R(L) acting on the separation holding member 151R(L) to rotate and move can be positioned at the accommodation position by the urging force of the tension spring 153, etc. 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 force applying member 152R (L) can be positioned at the accommodating position by the urging force of the tension spring 153 or the like. Therefore, when the process cartridge 100 is to be mounted to the imaging device main assembly 170, the mounting of the process cartridge 100 can be completed by moving in only one direction. Therefore, there is no need to move the process cartridge 100 (tray 171) in the vertical direction. Therefore, the imaging device main assembly 170 does not require additional space, and the main assembly can be reduced in size.

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

[0433] Furthermore, according to the present embodiment, the developing unit 109 can maintain the separation position only by the separation holding member 151R (L) included in the process cartridge 100. Therefore, by reducing the number of components that cause a change in the spacing amount between the developing roller 106 and the photosensitive drum 104, component tolerances can be reduced and the spacing amount can be minimized. Since the spacing amount can be reduced, when the process cartridge 100 is arranged in the image forming apparatus main assembly 170, the area occupied by the developing unit 109 when the developing unit 109 moves to the contact position and the separation position can be smaller, so that the image forming apparatus can be reduced in size. In addition, the space of the developer accommodating portion 29 for the developing unit 109 that moves to the contact position and the separation position can be increased, and therefore, a reduced-size and large-capacity process cartridge 100 can be placed in the image forming apparatus main assembly 170.

[0434] In addition, according to the present embodiment, when the process cartridge 100 is installed, the force applying member 152R (L) can also be positioned at the accommodating position, and the developing unit 109 can maintain the separation position only by the separation holding member 151R (L) of the process cartridge 100. Therefore, when the process cartridge 100 is installed to the main assembly 170 of the image forming apparatus, the process cartridge 100 can be installed by moving only in one direction. For this reason, there is no need to move the process cartridge 100 (tray 171) in the vertical direction. Therefore, the main assembly 170 of the image forming apparatus does not require space, and the main assembly can be reduced in size. In addition, since the separation amount can be reduced, when the process cartridge 100 is placed in the main assembly 170 of the image forming apparatus, the area occupied by the developing unit 109 when the developing unit 109 moves to the contact position and the separation position can be reduced, and thus the image forming apparatus can be reduced in size. In addition, since the space of the developer accommodating portion 29 for the developing unit 109 that moves to the contact position and the separation position can be increased, a process cartridge 100 that is reduced in size and has a large capacity can be placed in the main assembly 170 of the image forming apparatus.

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

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

[0437] Fig.40 This is an enlarged view of the periphery of the separation holding member 151R when the process cartridge 100 is viewed from the drive side along the swing axis K (photosensitive drum axis direction) of the developing unit 109. In addition, for ease of explanation, this is a cross-sectional view in which a portion of the developing cover member and a portion of the drive side cartridge cover member 116 are partially omitted through a partial section line CS. Fig.41It is an enlarged view of the periphery of the separation and holding member 151R when the process cartridge 100 is viewed from the non-driving side along the swing axis K (axis along the photosensitive drum axis direction) of the developing unit 109. In addition, for the sake of convenience of explanation, it is a cross-sectional view in which a part of the developing cover member 128 and a part of the driving side cartridge cover member 116 are partially omitted through the partial section line CS. Regarding the arrangement of the separation and holding member and the force applying member described below, there is no difference between the driving side and the non-driving side except for the part to be described in detail below, and they are common, and therefore, only the driving side will be described, which also applies to the non-driving side.

[0438] like Fig.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 the 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 driving 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 force applying member 152R is M4. In addition, the distance between the swing axis K and the point M2 of the developing unit 109 is distance e1, the distance between the swing axis K and the area M3 is e2, and the distance between the swing axis K and the point M4 is e3.

[0439] In the structure of the present 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. Fig.40 When viewed in the axial direction of the swing axis K (axial direction of the photosensitive drum) shown in FIG. 1 , at least a portion of the contact area M3 between the separation holding member 151R and the drive side cartridge cover member is placed on the side opposite to the side where the center (swing axis K) of the developing coupling 32 exists, relative to a line N passing through the center of the photosensitive drum 104 and the center of the developing roller. That is, the separation holding surface 151Rc of the separation holding member 151R is arranged 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 tolerance or the like, a change in the posture of the spacing position of the developing unit 109 can be suppressed. That is, the change in the separation holding surface 151Rc has an effect on the separation amount (gap) P1 (see FIG. 1 ) between the developing roller 106 and the photosensitive drum 104. Fig.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 an 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. Fig.15 ( Fig.16 ), the cylindrical portion 128b (127a) as the supporting portion of the developing unit 109 is provided at the end portion in the longitudinal direction. Therefore, by providing the force receiving portions 152Rk (Lk) and 152Rn (Ln) at positions opposite to the cylindrical portion 128b (127a) (i.e., the swing axis K) of the developing unit 109 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. Fig.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. Fig.40 As shown, the force applying members 152Rk and 152Rn are placed on the side indicated by the dotted line opposite to the rotation center K of the developing drive input gear 132 (developing coupling portion 132a) with respect to the extension line of the line N. By this arrangement, the functional elements can be efficiently arranged. That is, it leads to a reduction in the size of the process cartridge 100 and the imaging device M.

[0444] In addition, the contact portion between the separation holding member 151R and the urging member 152R is arranged so that the distance e3 is longer than the distance e1. Thus, the separation holding member 151R and the driving side cartridge cover member 116 can contact each other with a 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 , Fig.13 and Figure 55 to Figure 58The drum unit 103 shown is a drum unit including a photosensitive drum, a drum coupling (cartridge side coupling, coupling member) 143 and a drum flange 142 (see Fig.13 ) unit. The drum unit 103 is attachable to and detachable from the main assembly of the imaging device as a part of the cartridge 100. 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. Fig.43 and Fig.44 During image formation, the drum unit rotates in the direction of arrow A (see Figure 1 , Figure 55 to Figure 57 In the present 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 rotation 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 in 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 the present 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, the surface of the photosensitive drum 104 exposed from the outer shell of the box contacts the intermediate transfer belt 12a set in the main assembly of the imaging device. As a result, the toner image is transferred from the surface of the photosensitive drum 104 to the transfer belt 12a. Thereafter, the surface of the photosensitive drum 104 returns to a position close to the charging roller 105 inside the box.

[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 outer casing of the cartridge, and then returns to the inside of the outer casing of the cartridge and approaches the charging roller 105 again.

[0451] As described above, the cartridge 100 of the present 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) in the box 100 is relatively small. In the case of such a 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 the outside and cause the rotation speed to be unstable. For example, in the present embodiment, the developing roller 106, the charging roller 105 and the 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.43 ) drum drive coupling 180 rotates the drum unit (photosensitive drum 104) of the cartridge, a torque of a predetermined level or higher is required. 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 the present embodiment is manufactured by injection molding polyacetal resin. As the material, a resin material such as polycarbonate resin or polybutylene terephthalate resin can be used, or a resin material provided by mixing these with glass fiber, carbon fiber or the like. Alternatively, a processing method such as die casting or cutting can be used together with a metal material such as aluminum, iron or stainless steel.

[0455] Next, refer to Figure 1 , Figure 55 to Figure 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 direction outward (outward). In addition, the direction opposite to the outward direction (the direction of the arrow M1B) is referred to as the inward direction in the axial 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 of the photosensitive drum toward the driving side end portion 104a ( Fig.80 Alternatively, the outward direction in the axial direction (M1A direction) is Fig.14 In the direction from the non-driving side box cover 117 of the box 100 toward the driving side box 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 ( Fig.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) of the embodiment, the drum coupling 143 is mounted to one longitudinal end (drive side end) of the photosensitive drum 104. As described above, Figure 1 The shaft portion 143j shown is formed by a drive side cartridge cover member 116 (see FIG. Fig.15 ) is rotatably supported. The drum unit 103 is configured to be rotatable in a predetermined rotation 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 transmission 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 , Figure 52 to Figure 57 ). The protrusion has a driving force receiving portion 143b as a first side surface (first side portion) for receiving a 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 a 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 in the rotational direction A of the drum unit. Further, the braking force receiving portion 143c is a side surface (side portion) facing the downstream side in the rotational direction A.

[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] In addition, 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 (arrow MA1 direction). 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 ( Fig.13 ) on one side. 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 slope 143d is inclined to be outward in the axial direction (the direction of arrow MA1) toward the upstream side in the rotation direction (the upstream side in the direction of arrow A). That is, the slope 143d moves away from the non-driven side of the drum unit 103 as it moves toward the upstream side in the rotation direction. In other words, the slope 143d is inclined to move away from the photosensitive drum as it moves toward the upstream side in the rotation direction.

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

[0467] The spiral slope 143d includes a downstream portion (downstream top surface, downstream inclined slope, 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 slope 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 slope 143d is arranged upstream of the driving force receiving portion 143b and the downstream portion 143d1 of the spiral slope 143d in the rotation direction (see FIG. 143). Figure 55 to Figure 58 ).

[0468] In addition, since the length of the inclined surface 143d is measured along the rotation direction of the drum unit, the length of the upstream inclined surface 143d2 is greater than the length of the downstream inclined surface 143d1.

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

[0470] In addition, a circular hole portion 143a serving as an opening is provided in the protrusion of the drum coupling 143. The circular hole portion is for engaging with the positioning boss (positioning portion) 180i of the drum driving 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 shaft portion 143p formed along the axis L (see Figure 1 portion (a)), and the circular hole portion 143a is formed inside the shaft portion 143p. The shaft portion 143p is the portion for forming the circular hole portion 143a. Figure 1 ) and the circular hole portion 143a is formed inside the shaft portion 143p. The shaft portion 143p is the 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 space from the rotation axis L of the drum unit (see Figure 1 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 the above-mentioned shaft portion 143j.

[0473] The above-mentioned drum coupling 143 has an axisymmetric shape (axisymmetric shape) with respect to the axis L (see Figure 1 portion (a)). The driving force receiving portion 143b, the braking force receiving portion 143c, and the spiral inclined surface 143d are arranged at two positions so as to be separated by 180° in the circumferential direction, thereby providing a first coupling portion 143r and a second coupling portion 143s (see Fig.58 ).

[0474] Each coupling portion includes a driving force receiving portion 143b, a braking force receiving portion 143c, and a spiral inclined surface 143d, and the first coupling portion 143r and the second coupling portion 143s are placed at positions symmetric with respect to 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 Fig.43 , Fig.44 and Fig.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 connecting (engaging) with the drum coupling 143.

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

[0478] The driving 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 driving gear 201. The drum driving 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 driving gear 201. In addition, the drum driving 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 rotating in contact with the rotation stop portion 201b of the driving gear 201. The drive transmission unit 203 includes a plurality of components inside the cylindrical portion 180c of the drum driving 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 the braking force, and 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 a pushing force in the direction of the axis M1 (axial direction). The axis M1 is the rotation axis of the main component 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 protrudes 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 protruding in the form of a claw and engaging with the drum coupling 143, and a rotation stop protrusion 208c engaging with the rotation stop 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 engagement member 204 and the second brake engagement member 208 may be collectively referred to simply as the brake engagement members ( 204 , 208 ).

[0483] The first brake engagement member 204 is an outer brake engagement member disposed on the outer side in the radial direction, and the second brake engagement member 208 is an inner brake engagement member disposed 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 ( Fig.44 ). In the axial direction M1A, when the brake transfer member 207 is at the protrusion 207e of the brake transfer member 207 relative to the first brake engagement member 204 (see Fig.43 and Fig.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 where the protrusion 207e is not engaged with the protrusion 204e relative to the first brake engaging member 204 in the axial direction, 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 is engaged with an engagement hole 206c of a brake member 206 to be described below, so that the brake transmission member 207 and the brake member 206 rotate integrally.

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

[0486] The brake engaging member (204, 208) is connected to the brake member 206 through the brake transmission member 207 as described above. Therefore, the rotation torque of the brake engaging member (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 arranged 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 (pushing 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 disposed 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.44 ).

[0489] Thus, the drum drive coupling 180 also receives the forces of the drum drive coupling spring 210 and the brake engagement spring 211 through the brake transmission member 207. Due to the forces 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 regulated (restricted) by the axial direction restricting portion 212 (see Fig.44 ), so that the drum drive coupling 180 does not fall off from the main component side drive transmission unit 203. Specifically, when the drum drive coupling 180 moves a certain distance in the direction of arrow M1B, the flange portion 180a of the drum drive coupling 180 (see Fig.43 ) contacts the restricting portion 212 (see Fig.44 ). Thus, the movement and detachment of the drum drive coupling 180 can be suppressed.

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

[0491] In addition, when the brake engagement members (204, 208) are engaged with the coupling 143, the coupling engagement portions 204b, 208b can interfere with the coupling 143 (see Fig.60 , details will be described below). In this case, the brake engagement 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.61 ).

[0492] As described above, the brake engagement members (204, 208) are provided with a gap G from the brake transmission member 207 (see Fig.44 ). Within the range of the width of the gap G, the brake engagement members (204, 208) can move and retract in the M1A direction relative to the brake transmission member 207. Similarly, the brake engagement members (204, 208) can move in the direction of arrow M1A relative to the drum drive coupling 180 within the range of the width of the gap G. When the brake engagement members (204, 208) move in the direction of arrow M1A relative to the brake transmission member 207 and the drum drive coupling 180, the brake engagement spring 211 is compressed.

[0493] By the brake engagement 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 engagement members ( 204 , 208 ).

[0494] Together with the brake engagement members (204, 208), the drum drive coupling 180 also moves in the direction of arrow M1A. Fig.62 As shown, the drum drive coupling 180 and the first brake engaging member 204 are respectively provided with a protruding engaging portion 180u and an engaging portion 204u. Therefore, when the brake engaging member 204 moves a predetermined distance or more in the direction of the 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 M1A direction. 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 in the direction of arrow M1A relative to the brake transfer member 207, 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 member (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 it 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 transmission member 207 and the drum drive coupling 180.

[0497] Fig.45 204 is a perspective view showing the positional relationship between the drum drive coupling 180 and the brake engagement members (204, 208). Fig.45 Part (a) is a perspective view of only the drum drive coupling 180, and Fig.45 Portion (b) shows a perspective view of the drum drive coupling 180 and the brake engagement members (204, 208) both included therein. Fig.45 Parts (c) and (d) are illustrations 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 member (204, 208) is Fig.45There is a difference between parts (c) and (d).

[0498] like Fig.45 As shown in part (a) of the drum drive coupling (driving force applying member) 180, the drum drive coupling (driving force applying member) 180 includes a driving transmission surface 180d provided at each of two positions separated from each other by 180 degrees in the circumferential direction as a surface (driving force applying portion) engaged 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. Fig.60 ).

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

[0501] Fig.45 Part (d) of FIG. 1 shows a state in which the coupling engagement portions 204b and 208b are in a phase relationship away from the drive transmission 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] Fig.46 A sectional view of the main assembly 170 of the image forming apparatus is shown around the main assembly side drum drive coupling 180. Fig.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 through a link mechanism (not shown) connected to the front door 111. That is, the drive transmission unit 203 is in a state of moving away from the process cartridge 100 and the drum coupling 143 (see Fig.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 the 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 the arrow M1B and interferes with the approaching drive transmission unit 203 ( Fig.61 , Fig.65 and Fig.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 not engaged.

[0509] In order to make the drum coupling 143 and the main component side drum drive coupling 180 in 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 promoted until the drum drive coupling 180 on the main component 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, will be described divided into a plurality of cases depending on the phases of the drum coupling 143 and the main assembly side drum drive coupling 180.

[0511] Fig.47 Part (a) shows the drum coupling 143, and Fig.47 Part (b) shows the drive transmission unit, both of which are viewed in the axial direction. Fig.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 and a shield (shield portion) 143g (see FIG. 143b ) are provided to engage with the positioning boss (positioning portion) 180i of the drive coupling 180. Fig.47 and Figure 1 The shield plate is used as 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 arranged in a range between R1 and R2. The braking force receiving surface 143c is Fig.47 The part (a) is not visible in the line of sight and is Figure 1 In the range between R2 and R3, a part of the driving force receiving portion 143b, a part of the spiral slope 143d, and a part 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, Fig.47 The same symbols R1 to R3 are used in part (b) to indicate the same range as the coupling 143.

[0514] exist Fig.47 In the range of the radius indicated by R1 in the portion (b) of the drum coupling 143, 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 as a part of the coupling engaging portion 208b of the engaging member 208 is arranged. In the range indicated by R1 to R2, the coupling engaging portion 208b of the second brake engaging member 208 is arranged. The drive transmission surface 180d and the first brake engaging member 204 are arranged in the range indicated by R2 to R3.

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

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

[0517] The drum coupling 143 includes two coupling parts 143s and 143r arranged 180° 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] Fig.48 Part (a) of FIG. 1 shows a state in which the drive transmission surface 180d of the drive transmission unit 203 and the second brake engagement member 208 are close to each other. Fig.48 As shown in part (a), the phases of the inclined start portion 143f of the drum coupling 143 and the inward protrusion 208e of the second brake engagement member 208 have the following relationship. That is, the inclined 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] Fig.48 Part (b) shows the drive transmission unit 203 from Fig.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 engagement member 204.

[0520] Fig.48 Part (c) shows a state in which the drive transmission unit 203 moves further in the direction of the arrow M1B. The spiral ramp 143d stops the approaching second brake engaging member 208. As a result, the movement of the second brake engaging member 208 in the direction of 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 the 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 the arrow M1A.

[0521] When this state is reached, as shown in reference Fig.44 As described above, because the second brake engaging member 208 is disconnected from the brake member 206, the second brake engaging member 208 can rotate without receiving a rotational load. At this time, the brake member 206 receives an elastic force F1 in the direction of the rotation axis M1 through the drum drive coupling spring 210 and the brake engaging spring 211 provided inside the drive transmission unit 203. The spiral inclined surface 143d moves the second brake engaging member 208 without a rotational load in the direction of the arrow C by the component force of the elastic force F1. That is, the second brake engaging member 208 moves to the downstream side in the rotation direction A along the spiral inclined surface 143d.

[0522] Fig.48Part (d) shows the state immediately after the second brake engaging member 208 moves to the downstream side in the rotational direction (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 as a guide portion has a downstream portion 143d1 and an upstream portion 143d2. The downstream portion (downstream side inclined surface, downstream side top surface, downstream side inclined portion) 143d1 is placed between the braking force receiving portion 143c and the driving force receiving portion 143b. The upstream side portion (upstream side inclined surface, upstream side top surface, upstream side inclined portion) 143d2 is on the upstream side in the rotation direction (direction A) relative to the driving force receiving portion 143b. Therefore, the second brake engaging member 208 can be smoothly guided from the upstream side portion 143d2 of the inclined surface 143d to the braking force receiving portion 143c through the downstream side portion 143d1.

[0523] Fig.48 Part (e) shows a state in which the drum coupling 143 moves (rotates) in the direction of arrow A by rotating the 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 comes into contact with 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] Fig.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. Fig.43 ) is connected to the second brake member 208 so as to move integrally with the second brake member 208. Fig.48 Part (a) to Fig.48 During the process shown in part (e) of FIG. 1 , the first brake engaging member 204 also moves along the same line as the second brake member 208. Fig.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 Fig.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. Fig.76 is shown in part (a).

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

[0529] Fig.60 It is shown that Fig.48 That is, the inclined 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 engagement member 208 are close to each other. Fig.61 A state is shown in which the drive transmission unit 203 has moved in the direction of arrow M1B from this state.

[0530] Fig.61 Shown corresponding to Fig.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 engagement 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 is not changed. Fig.62 A state in which the drive transmission unit 203 is further moved in the direction of arrow M1B from this state is shown.

[0531] Fig.62 Shown corresponding to Fig.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 the arrow M1A.

[0532] In this state, as referenced Fig.44 As described above, because the second brake engaging member 208 is disconnected from the brake member 206, the second brake engaging member 208 can rotate without receiving a rotational load. At this time, the brake member 206 receives an elastic force F1 in the direction of the rotation axis M1 through the drum drive coupling spring 210 and the brake engaging spring 211 arranged inside the drive transmission unit 203. The spiral inclined surface 143d moves the second brake engaging member 208 without a rotational load in the direction of the arrow C by the component force of the elastic force F1. That is, the second brake engaging member 208 is rotationally moved to the downstream side in the rotation direction A along the spiral inclined surface 143d.

[0533] Fig.63 1 shows a state immediately after the second brake engagement member 208 moves to the downstream side in the rotational direction (the direction of arrow A), and corresponds to Fig.48 The second brake engaging member 208 moves along the spiral slope 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, and the trajectory of the movement is shown by the arrow D. Therefore, the brake engaging members (204, 208) move away from the drive coupling 180 toward the downstream side in the rotation direction A to a position where they can engage with the second side surface (braking force receiving portion 143c) of the drum coupling 143. When reaching this position, the brake engaging members (204, 208) return to a state where a braking force can be generated.

[0534] Fig.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 . Fig.64 Corresponds to Fig.48 part (d).

[0535] When the drum drive coupling 180 of the drive transmission unit 203 is Fig.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 engagement member 208 through the braking force receiving portion 143c (see Fig.48 part (e)).

[0536] In short, through Fig.48 Parts (a) to (e) and Figure 60 to Figure 64 1. 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 engagement member (204, 208) is moved from its position adjacent to the drive transmission surface 180d ( Fig.48 Part (a) and Fig.60 ) moves to a position where the drum coupling 143 is sandwiched between the drive transmission surface 180d and the brake engagement member (204, 208) ( Fig.48 Part (d) and Fig.64 )).

[0538] When the drive transmission surface 180d is Fig.48 Part (d) and Fig.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 Fig.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 member (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 Fig.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 parts 143s and 143r, but for simplicity, only the coupling part 143s will be described.

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

[0541] Fig.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 143g of the drum coupling 143 comes into contact with the inward protrusion 208e of the second brake engaging member 208 approaching in the M1B direction.

[0543] Next, Fig.49 Part (b) shows a state in which the shutter portion 143g stops (blocks) 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, 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 the 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 in the M1B direction only, the second brake engagement member 208 moves in the M1A direction relative to the drum drive coupling 180. As described above, by this relative movement, the second brake engagement member 208 transitions to a state where it can rotate without receiving a rotational load.

[0545] Then, Fig.49 Part (c) shows a state where the drive transmission unit 203 has started to rotate in the rotation direction A. First, when the drum drive coupling 180 starts to rotate in the A direction, it is pushed by the drum drive coupling 180, and the second brake engagement member 208 also starts to rotate 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 rotation direction A and the M1B direction.

[0547] Fig.49 Part (d) of Fig.48 The state after the second brake engaging member 208 moves along the spiral slope 143d of the drum coupling 143 and passes through the inclined surface 143d is shown in part (d). At this time, the entire drive transmission unit 203 moves further 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 of arrow D.

[0548] Subsequent joining operations and Fig.48 The same as described in part (d), and the subsequent bonding completion state is as follows Fig.48As shown in part (e). In the present embodiment, the shroud portion 143g is continuous with the upstream side (upstream side slope, upstream side top surface) 143d2 of the spiral slope 143d. The inclination start portion 143f is the 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 can be set between the shroud portion 143g and the slope 143d.

[0549] Also in Fig.49 Part (a) to Fig.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, Fig.49 Part (a) to Fig.49 During the process of part (d), the first brake engaging member 204 (see Fig.43 ) moves integrally with the second brake engagement member 208.

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

[0551] Fig.65 The state in which the drive transmission surface 180d of the drive transmission unit 203 and the second brake engagement member 208 approach each other is shown. At this time, the shutter 143g of the drum coupling 143 is in contact with the second brake engagement member 208 approaching in the M1B direction. Fig.65 Corresponds to Fig.49 part (a).

[0552] Next, Fig.66 2 shows a state where the drum drive coupling 180 has been moved to the right side (M1B direction) in the axial direction relative to the second brake engagement member 208. Fig.66 , the shutter portion 143g is in a state of stopping (blocking) the advancement of the approaching second brake engagement member 208.

[0553] Fig.66 Corresponds to Fig.49The second brake engaging member 208 moves to the left side (M1A direction) in the axial direction relative to the drum drive coupling 180. As described above, by 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, Fig.67 A state in which the drive transmission unit 203 has started rotating in the rotation direction A is shown. Fig.67 Corresponds to Fig.49 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 second brake engaging member 208 passes the slope start portion 143f. Fig.68 Corresponds to Fig.49 Part (d). Fig.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. Fig.48 Part (d) and Fig.63 In addition, 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. Therefore, the first brake engaging member 204 moves along the trajectory of the arrow D.

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

[0556] Next, refer to Fig.50 Part (a) to Fig.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 parts 143s and 143r, but for simplicity, only the coupling part 143s will be described.

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

[0558] Fig.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, Fig.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 position is different in the radial direction.

[0560] Then, Fig.50 Part (c) of FIG. 1 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] Fig.50 Part (d) shows a state in which the second brake engaging member 208 is further rotated and has passed the inclined 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. Fig.48 The subsequent operations are the same as those described above, and therefore the description is omitted.

[0562] Also in Fig.50 Part (a) to Fig.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 Fig.50 Part (a) to Fig.50 During the process of part (d), the first brake engaging member 204 (see Fig.43 ) also moves integrally with the second brake engaging member 208.

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

[0564] Fig.69 Corresponds to Fig.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, Fig.70 Corresponds to Fig.50 Part (b) of the drawing 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 stops the advancement of the approaching second brake engaging member 208, and the drum drive coupling 180 has moved to the right side (M1B direction) in the axial direction beyond the second brake engaging member 208. At this time, the second brake engaging member 208 moves to the left side (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, Fig.71 Corresponds to Fig.50 , and shows a state in which the drum drive coupling 180 of the drive transmission unit 203 contacts the second brake engagement member 208 by rotating in the rotation 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, the Fig.71 The state shown, in which the drum drive coupling 180 is in contact with the second brake engagement member 208.

[0568] Fig.72 Corresponds to Fig.50 , and shows a state in which not only the drum drive coupling 180 but also the second brake engaging member 208 starts to rotate in the direction A by the engagement between the drum drive coupling 180 and the second brake engaging member 208. More specifically, this is a state in which the second brake engaging member 208 passes through the inclined starting portion 143f of the drum coupling 143 by the second brake engaging member 208 being pushed by the drum drive coupling 180 to rotate in the direction A. 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. Fig.48 Part (c) and Fig.62 As described in.

[0569] Subsequent operations are similar to those mentioned above. Fig.48 Part (c) to Fig.48 Part (e) and Figure 62 to Figure 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 (arrangement) of the drive transmission unit 203 relative to the drum coupling 143 is not predetermined ( Fig.48 Part (a)), Fig.49 (a) Fig.50 Part (a), Fig.60 , Fig.65 , Fig.69 ). However, in any case, the drum coupling 143 may 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), with which the drum coupling 143 may engage.

[0571] Next, refer to Fig.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. Fig.51 is a cross-sectional view of the drive transmission unit 203 and the drum coupling 143, and Fig.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 arranged so that when the drive transmission unit 203 is still separated in the axial direction M1B, the deviation between each other is eliminated when the engagement starts 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 engage with the positioning boss 180i without providing a guide surface, such as Fig.51 In addition, Figure 6 As shown in part (c) of FIG. 1 , the guide surface 143h may be enlarged to reduce the fit between the circular hole portion 143a and the positioning boss 180i. Fig.51 As shown in part (d) of FIG. 1 , the diameter of the circular hole portion 143a may be increased. These arrangements may be selected depending on how the relative position and accuracy between the drive transmission unit 203 and the process cartridge 100 are determined.

[0573] It is desirable that the circular hole portion 143a has a sufficient length to accommodate the positioning boss 180i. Fig.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 Fig.95 In the present 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 region Pb.

[0575] The structure is such that a projection 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 projection 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 main assembly of the image forming apparatus. Furthermore, the coupling 143 operates the braking mechanism (braking member 206) inside the drive transmission unit 203 according to the driving force received from the drive transmission unit 203. The drum coupling 143 can receive the braking force through the brake engaging member (204, 208).

[0577] By using 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 feeding 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 in contact with the photosensitive drum 104. Therefore, the torque of the photosensitive drum 104 is relatively small, and the speed of the photosensitive drum 104 tends to fluctuate when the photosensitive drum 104 is affected by the surrounding environment during its rotational drive. 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 to the box provided with a cleaning device from the drive transmission unit 203 of the present embodiment through the coupling 143. When the box 100 is provided with a cleaning device (e.g., a cleaning scraper) that contacts the surface of the photosensitive drum to remove toner from the photosensitive drum, a friction force is generated between the photosensitive drum and the cleaning device. This friction 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 increases, 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 the present embodiment, a braking mechanism for applying an appropriate rotational load to the photosensitive drum is arranged not on the cartridge side but on the main assembly side of the image forming apparatus, more 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 (detachably mountable unit). It can contribute to miniaturization and cost reduction of the process cartridge.

[0582] In addition, the coupling 143 has such a shape that it can smoothly engage with both the driving force applying member (drum drive coupling 180) and the braking force applying member (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 again to Fig.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, and each coupling part includes an engagement part 143i and a guide forming part 143j. The engagement part 143i is a shaped part for engaging with a driving force applying member (drum drive coupling 180) or a braking force applying member (brake engagement member (204, 208)). The engagement part 143i forms a driving force receiving part 143b, a braking force receiving part 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 of 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 rotation direction, and the braking force receiving portion 143c is the side portion facing downstream in the rotation direction.

[0588] In addition, the guide forming portion 143n is a protrusion (extending portion) extending toward the engaging portion 143i in the rotation direction. The top surface (upper portion) of the guide forming portion 143n is an upstream side inclined surface (upstream side top surface, upstream side inclined portion) 143d2. The upstream inclined surface 143d2 is a guide portion (upstream side 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 forming portion 143n is a protrusion for forming the upstream side inclined surface 143d2 as a guide (upstream side guide).

[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 to approach the non-driving end of the photosensitive drum from upstream to downstream in the rotation direction (see Fig.80 ).

[0591] exist Fig.80In the embodiment, 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 the driving force from the drum coupling 143.

[0592] The end on the opposite side of the photosensitive drum 104 relative to the first end portion 104a is the non-driven side end (second end) 104b. The distance from the non-driven side end portion 104b to the upstream side inclined surface 143d2 is 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 rotation 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 regarded as the distances from the cartridge housing (i.e., the non-drive side cartridge cover 117: see Fig.14 ) is measured from the non-driving side end to the upstream slope 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 the present embodiment, the first shape portion and the second shape portion (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 rotation direction. However, although the engaging portion 143i and the guide forming portion 143n are adjacent to each other, they may not be connected but a gap may be provided between them.

[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 engagement portion 143i is a portion of the guide portion, similar to the upstream slope 143d1, which has the function of guiding the brake engagement member (204, 208) to a position where the brake engagement member can engage with the braking force receiving portion 143c.

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

[0601] like Fig.48 Part (c), Fig.49 Part (c), Fig.50 Part (d), Fig.62 , Fig.67 and Fig.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-driving 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 Fig.48 Part (d), Fig.49 Part (d), Fig.63 , Fig.68 ). Therefore, the brake engaging member (204, 208) can engage with the braking force receiving portion 143c.

[0603] The brake engaging member (204, 208) is guided by the inclined surface 143d, and the brake engaging member (204, 208) moves 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 member (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. Fig.48 Part (d) Fig.48 Part (e), Fig.49 Part (d), Fig.63 , Fig.64 , Fig.68 ).

[0604] The spiral slope 143d also has a function of keeping the brake engagement 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.48 Part (a), Fig.47 , Fig.56 By expanding the area where the inclined surface 143d is provided, the top surface 143d can reliably guide the brake engagement 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 Fig.49 When the braking force receiving portion 143c is moved to the space on the downstream side of the braking force receiving portion 143c by passing through the upstream inclined surface 143d2, Fig.49 (c) and 49(d)).

[0607] In the present embodiment, the entire inclined surface 143d is an inclined portion. Both the downstream top surface 143d1 and the upstream side 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 Fig.81 Part (a) and Fig.81 (b)). Fig.81 Part (a) and Fig.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 slope (upstream top surface) 143d2, and by utilizing the inertia (momentum) of the movement, it passes through the flat downstream top surface 143d1.

[0609] In addition, 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. Fig.74 Describe this structure.

[0610] It is also conceivable to provide a local rising portion in the downhill spiral ramp 143d. Even in this case, if the brake engagement member (204, 208) can be fully guided by the ramp 143d downstream in the rotational direction, the ramp 143d can be considered as a downhill ramp. That is, even if the ramp is locally raised, the spiral ramp 143d can be considered as a descending ramp as a whole. In other words, the distance from the non-driving end of the box to the spiral ramp 143d can be considered to decrease as the spiral 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 falling portions, or the rising slope is not too steep, and therefore, the rising portion has less influence on the falling 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 line (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 extending 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 to the following. Fig.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.47 and Fig.56 ). In contrast, the downstream slope 143d1 has a wider area than the upstream slope 143d2.

[0614] Here, the width of each slope is the length measured along the radial direction. Fig.79 As shown, at least a portion of the engaging portion 143i is placed farther than the guide forming portion 143n in the radial direction of the drum unit relative to the axis L of the drum unit. In other words, at least a portion of the engaging portion 143i is placed 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 arranged near the boundary between the guide forming portion 143n and the engaging portion 143i. That is, a part of the engaging portion 143i extends outward from the guide forming portion 143n in the radial direction, so that the driving force receiving portion 143b is formed. 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 disposed closer to the non-driving side end portion of the photosensitive drum than the upstream side inclined surface 143d2. Fig.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 (i.e., the non-drive side cartridge cover 117: see Fig.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 blocks 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. Fig.66 , Fig.49 Part (b), Fig.69 , Fig.50 Part (a) shows the blocking state.

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

[0621] When the brake engaging member (204, 208) enters the space upstream of the driving force receiving portion 143b or the space downstream of the braking force receiving portion 143c together with the drum drive coupling 180, the brake engaging member (204, 208) cannot engage with the braking force receiving portion 143c. The shutter portion 143g blocks the movement of the brake engaging member (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.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] In addition, the shutter portion 143d has a width sufficient to cover at least a part of the downstream side portion (downstream inclined surface 143dl) of the spiral inclined surface (top surface) 143d. Thus, the shutter portion 143d restricts the brake engagement 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 engagement members (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.50 part (d) of Fig.49 part (c) of Fig.48 part (c)).

[0625] That is, the brake engagement members (204, 208) contact the upstream inclined surface 143d2 after passing through the shutter portion 143g and are guided along the inclined surface 143d toward the space on the downstream side of the braking force receiving portion 143c (see Fig.49 part (c) of Fig.50 part (d)).

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

[0627] The shutter portion 143g is adjacent to the upstream inclined surface 143d2 and upstream of the upstream inclined surface 143d2. In the present embodiment, the top surface of the shutter portion 143g and the upstream inclined surface 143d2 are continuous, but there may be a case where the shutter portion 143g and the upstream inclined surface 143d2 are adjacent to each other but a gap is formed therebetween.

[0628] In addition, the top surface of the shutter portion 143g has a plane perpendicular to the axis L of the drum unit, but the shape is not limited to this example. For example, it is conceivable that the top surface of the 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 part of the upstream inclined surface 143d2. Alternatively, it can be considered that a part of the guiding portion forming part 143n forms the shutter portion 143g.

[0629] Furthermore, in the present 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. Fig.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. Fig.76 as shown in part (a).

[0630] Hereinafter, another example (modified example) of the 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 a braking force applying member (brake engaging member) which applies a braking force for applying a load to the rotation of the photosensitive drum to the coupling 143. There is a gap between the first brake engaging member and the second brake engaging member 208, and the second brake engaging member disposed radially inward is slightly flexible to move outward so as 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] There will be described 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 according to conditions.

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

[0635] Reference Fig.52 Describe the shape. Fig.52 14 is a view showing one end of the drum unit, and shows a state where 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 Fig.53 The process of engaging with the drive transmission unit 203 is described.

[0637] Fig.53 The expansion diagram of Fig.48 The drum coupling 143 includes two coupling parts 143s and 143r, but for simplicity of description 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 Fig.53 The phase of the inclination start portion 143f of the drum coupling 143 and the inward protrusion 208e of the second brake engagement member shown in part (a) satisfies the following relationship. That is, the case where the inclination start portion 146f of the drum coupling 143 is on the downstream side of the rotation direction (arrow A) will be described.

[0639] Fig.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 Fig.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 ramp 143d3.

[0641] Fig.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. Fig.48 As described above, second brake engagement 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 the arrow E.

[0643] However, the second brake engaging member 208 is Fig.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 the arrow E. The component force varies according to the load torque of the drum holding unit 108 and the angle (θ1 or θ2) of each inclined surface. Considering 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] Fig.53 The portion (d) of FIG. 1 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 inclined start portion 146f of the drum coupling 146. When this state is reached, the second brake engaging member 208 moves in the direction of the arrow C, as shown in FIG. Fig.48 The subsequent operations are the same as those described above, and therefore their description will be omitted.

[0645] Despite Fig.50 Part (a) to Fig.50 Not shown in part (d) of FIG. 2 , 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 ramp 143. More specifically, the spiral ramp 143 is a portion that is inclined toward the non-driven side of the drum unit as the spiral ramp 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 FIG. 1 ) of the photosensitive drum) as the push-back surface moves downstream in the rotational direction A. Fig.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] In addition, another modified shape of the drum coupling 143 will be described. The inclined portion and the top surface (helical slope 143d) of the guide portion described in Embodiment 1 are formed as smooth slopes, and the brake engaging member (204, 208) is guided along such slopes (see Fig.56 However, the drum coupling 143 can function even if the inclined portion has other shapes. Fig.54 An example of this is shown in a perspective view in FIG.

[0649] first, Fig.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, Fig.54 Part (b) and Fig.73 The shape of part (a) shows a modified example. The height changes stepwise between the inclination start portion 147f and the braking force receiving portion 147c. That is, the top surface (inclined portion) has a step 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 Fig.73 The second brake engaging member 208 is moved by moving the stepped step portion 147d in the direction of the arrow C in the portion (a) of the brake engaging member 208, thereby performing the Fig.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 the limitation of the structure of the mold for manufacturing the coupling 143, the 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 contact 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, Fig.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 this structure. Similar to the inclined surface 143d, the step 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 Fig.54 Part (c) and Fig.73 As shown in part (b), the top surface is divided into an inclined surface (upstream side top surface, downstream side top surface) 148d1 and an inclined surface (downstream side top surface, downstream side guide, downstream side) 148d2, wherein the inclined surface 148d1 and the inclined surface 148d2 have a gap 148g therebetween. Also in this case, if the second brake engaging member 208 has a shape that does not cause a seizure when it contacts the top surfaces (148d1, 148d2), the top surfaces (148d1, 148d2) can be used as guides. This coupling can be used when there are limitations in the structure of the mold for molding the coupling.

[0655] also, Fig.54 Part (d) and Fig.73 Part (c) shows a modified example in which the shape of each part of the coupling 143 is formed by ribs. The top surface (inclined surface 149d) includes the surface of the plurality of ribs 149p, and the top surface is divided into the plurality of ribs, and in this case, the same function can be provided. That is, as Fig.73 As shown in part (c), the guide forming portion 149n forming the upstream top surface (upstream guide, 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 ribs without producing thick parts.

[0656] That is, for Fig.54 Part (a) to Fig.54Each structure of the portion (d) of the brake engaging member (204, 208) is such that 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, Fig.52 The push-back surface (push-back portion) 143k shown in the figure may have various shapes. For example, the push-back portion (push-back surface) 143k of the modification is a smooth continuous spiral slope, but the push-back portion may be inclined by a plurality of surfaces or steps. For example, the push-back portion 143k may include two surfaces with different inclinations, such as Fig.48 Part (b) and Fig.56 The push-back portion 143k of the embodiment 1 shown in the portion (d) is the same. In addition, although the push-back surface 143k is raised, a descending portion may be provided locally.

[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, Fig.48 Part (b), Fig.55 Part (b) and Fig.56 The drum coupling 143 of Embodiment 1 shown in the part (d) of has a structure in which not only the shutter portion 143g but also the push-back portion 143k is provided. Generally, the drum coupling 143 can prevent the incorrect entry and approach of the brake engagement member (204, 208) 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 engagement member (204, 208) back away from the coupling 143.

[0659] The drum coupling 143 has a push-back surface 143k (see Fig.79 Part (b) and Fig.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.79 ) may be referred to as a first shape portion, a second shape portion, a third shape portion and a fourth shape portion, respectively, in no particular order.

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

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

[0663] That is, due to this shape, when the braking force receiving portion 143c is engaged with the brake engaging member (204, 208), a force is generated so as to attract each other. The braking force receiving portion 143c extends toward the downstream side in the rotation direction. Therefore, when the braking force engaging member (204, 208) contacts the braking force receiving portion 143c, a force is generated so that the braking force engaging member (204, 208) is attracted inwardly toward the drum coupling 143 or the photosensitive drum 104 in the axial direction. 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.67 and Fig.68 ). However, if the brake engaging member (204, 208) moves 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 is likely to be destroyed or become unstable. Therefore, it is preferred that the braking force receiving portion 143c has a shape for stabilizing the engagement state with the brake engaging member (204, 208) to suppress the movement of the brake engaging member (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. Fig.54 Part (e) and Fig.73 In part (d) of Fig.54 Part (e) and Fig.73 In the modified drum coupling shown in (d), the braking force receiving portion 144c does not protrude toward the downstream side in the rotation 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 means for stabilizing the engagement state with the brake engagement 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 force 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 force between the braking force receiving portion 144c and the brake engagement member (204, 208) increases due to the viscosity of the double-sided tape (adhesive member). In addition, it is conceivable to increase the friction coefficient of the braking force receiving portion 144c by performing surface treatment on the braking force receiving portion 144c without using the elastic member 144t.

[0669] It is desirable that the helical ramp 143d (see Fig.67 ) has a small friction coefficient to achieve smooth guidance. Therefore, even when a material with a high friction coefficient is selected or a surface treatment is applied to the braking force receiving portion 144c, it is desirable that this method is not used for the entire coupling, but the use of such a material or such a surface treatment is not applied to the spiral slope 143d. That is, it is desirable that the friction coefficient of the braking force receiving portion 144c is higher than the friction coefficient of the spiral slope 143d.

[0670] like Fig.54 Part (a) to Fig.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 Fig.101 , the preferred arrangement relationship and dimensional relationship of the drum coupling 143 will be described. Fig.1011 is a front view of the drum coupling 143 of Embodiment 1, wherein θ (theta) 11 is a value indicating the dimension of the engaging portion 143i from the driving force receiving portion 143b to the braking force receiving portion 143c 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 Fig.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, 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, Fig.74 In the modified example of the drum coupling shown, the thickness of the engaging portion 145i corresponding to the engaging portion 143i is made smaller than that in the present embodiment by forming the drum coupling 143 from metal. Fig.101 ) is that θ11 is 1°, more preferably 2° or even more preferably 8° or more. In the present embodiment, θ11 is set to be 30° or more, and θ11 is set to be about 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 a length, it becomes the thickness of the engaging portion 143i, ie, 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, Fig.101θ12 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 of 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 by 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, but when expressed in numbers, θ12 is 1° or more, more preferably 2° or more, still more preferably 8° or more, and even more preferably 30° or more. In the present 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 about 67°.

[0680] In the following we will refer to Fig.102 and Fig.103 A structure in which θ12 is larger than θ12 of the present embodiment is 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 more, and more preferably 8° or more. In addition, θ13 is preferably 360° or less, and more preferably 270° or less. In the present embodiment, θ13 is set to 180° or less. Specifically, θ13 is set to about 102°.

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

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

[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 forming portion 145n having a spiral slope 145d. The engaging portion 145i and the guide forming portion 145n correspond to the engaging portion 143i and the guide forming portion 143n of the coupling 143 shown in Embodiment 1 (see Fig.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 to connect the braking force receiving portion 145c from the inclined 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. Fig.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 ( Fig.74 The spiral slope 145d in ) corresponds to the embodiment 1 ( Fig.57 )'s top surface of the upstream slope 143d2.

[0687] On the other hand, in this modification ( Fig.74 ), the top surface (upper portion) 145e of the engaging portion 145i ( Fig.74 Part (b)) corresponds to Example 1 ( Fig.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 Fig.57 The length of the downstream inclined surface 143d1 in. 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 such a structure, the spiral 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 plane 145h is adjacent to the upstream of the spiral slope 145d, and the spiral slope 145d and the plane 145h are connected to each other. The plane 145h may 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 may have the shutter portion 143g of the push-back surface 143k described in Embodiment 1 or another modification of Embodiment 1 (see Figure 1 , Fig.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, Fig.75 The shape of a modified example of the drum coupling is shown. Fig.75 In the example shown in FIG. 1 , 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. 1 ). Fig.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 Fig.76 Part (b), Fig.76 Part (c), Fig.78 Part (a), Fig.78 Part (b), Fig.78 Part (c) and Fig.78 These figures show a drum coupling in which the two coupling parts 143s and 143r have different shapes. Fig.76 Parts (b) and (c) are expanded views of the coupling 143, and Fig.76 In part (c) of the drawing, the drum drive coupling 180 and the brake engaging member 208 provided in the main assembly side of the apparatus are also shown in an expanded view. Fig.78 Part (a) and Fig.78 Part (b) is a perspective view of the drum coupling 143. In addition, Fig.78 Part (c) and Fig.78 Part (d) shows the engagement state of the brake engagement member (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 only includes a driving force receiving portion 143b. That is, the side surface 143y provided on the engaging portion 143i of the coupling portion 143s is not engaged 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 is not engaged with the drum drive coupling 180.

[0695] Another example of an asymmetric coupling 143 is shown in Fig.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 Fig.76 Part (b), Fig.76 Part (c), Fig.78 Part (a), Fig.78 Part (b), Fig.78 Part (c) and Figure 7 The modified example of the coupling 143 shown in FIG. 1 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 matching accuracy between the circular hole portion 143a and the positioning boss 180i of the drum drive coupling 180 (see FIG. 14). Fig.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, Fig.77 Another modification of the drum coupling including one driving force receiving portion and one braking force receiving portion is shown. Fig.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. Fig.77 Part (a) is a perspective view of the drum coupling, and Fig.77 Part (b) is its front view.

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

[0699] For example, Fig.96 As shown, Fig.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, no matter which of the two 180° symmetrical positions is the position where one spiral slope 143d is provided, the slope 143d can act on the entire brake engagement member (204, 208). Similarly, the extrusion surface 143k can be placed at either of the two positions that are 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 ( Fig.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 Fig.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 part 143i but does not have a guide forming part 143n, and the other coupling part 143r has a guide forming part 143n but does not have an engaging part 143i. Such a structure is conceivable. An example of such a structure is shown in FIG. Fig.97 Parts (a) and (b) are shown. Fig.97 Part (a) is a perspective view of a modified example of the drum coupling, Fig.97 Part (b) is its front view.

[0705] In the modified example of the drum coupling shown in these figures, the guide forming part 343n and the engaging part 343i have one. The guide forming part 343n forms a spiral slope (guide, top surface, inclined portion) 343d2. The engaging part 343i forms a driving force receiving part 343b and a spiral slope (guide, top surface, inclined portion) 343d1. The guide forming part 343n and the engaging part 343i are located on opposite sides of the axis L. In addition, in this modification, the braking force receiving part 343b is not arranged at the engaging part 343i, but is arranged at the downstream end portion in the rotation direction of the guide forming part 343n. That is, the engaging part 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] Fig.99 Parts (a), (b) and (c) of the present invention show the engagement process of the drum coupling and the brake engagement member (204, 208) of the modified example in this order. For convenience of explanation, the drum drive coupling 180 of the drive transmission unit 203 is not shown.

[0707] like Fig.99 As shown in part (a) of FIG. 1 , when the second brake engaging member 208 contacts the inclined surface 343d2 of the guide 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 Fig.99 As shown in part (b), 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. Fig.99 The first brake engaging member 204 reaches a position where it can engage with the braking force receiving portion 343c (see Fig.97 part (b)).

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

[0710] like Fig.98 As shown in part (a), 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] Fig.98 Part (b) shows angles θ41, θ42, θ51, and θ52 regarding the size of each portion in this modification.

[0712] Angle θ41 is an angle of the area where the engaging portion 343i is arranged. θ42 is an angle of the area occupied by the spiral slope 343d2 of the guide forming portion 343n. θ51 is an 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 an angle of the area occupied by the portion 343d2a on the spiral slope 343d2 located on the upstream side in the rotation direction from the position S343b of the imaginary arranged driving force receiving portion.

[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 member (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 Fig.101 The preferred range of θ52 is the same as that of θ12. In addition, since θ42 corresponds to Fig.101 The angle of θ13 in θ42 is the same as that of θ13.

[0717] In addition, Fig.100 Part (a) and Fig.100 Another modification of the asymmetrical drum coupling is shown in part (b). The structure is such that the upstream slope 143d2 (see Fig.58 The joint portion 143i is separated from the upstream side slope 143d2 by the upstream side slope 143d2a and the downstream side slope 143d2b.

[0718] exist Fig.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 Fig.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 slope 143d2 is hypothetically moved to a position 180° symmetrical is the area S143d2b. At this time, the angle of the area occupied by the virtual area S143d2b and the upstream portion 143d2a is θ32. Since θ32 corresponds to Fig.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] In addition, 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 can be changed to be smaller than the drum coupling ( Figure 1 etc.) are long. This example is Fig.102 and Fig.103 In the drum coupling shown in these figures, the spiral slope 443d2 corresponding to the upstream slope 143d2 extends to more than 360°. That is, the spiral slope 443d2 extends over a full circle.

[0722] The engaging portion 443i corresponding to the engaging portion 143i of the first embodiment is provided separately from the inclined surface 443d2. The engaging portion 443i includes a braking force receiving portion 443c1 and a driving force receiving portion 443b. The braking force receiving portion 443c2 is also provided near the end of the spiral inclined surface 443d2. The braking force receiving portion 443c1 and the braking force receiving portion 443c2 are arranged at a 180° symmetrical position.

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

[0724] like Fig.103 As shown, the brake engaging member (204, 208) rotates one or more circles by being guided by the spiral ramp 443d2. In this way, the length of the spiral ramp 443d2, which serves as a guide and an inclined portion, can be increased to more than 360°. However, if the spiral ramp 443d2 is longer, it may be that the time required for the brake engaging member (204, 208) to pass through the spiral ramp 443d2 is longer, or the speed of the brake engaging member (204, 208) on the spiral ramp 443d2 is slower. In order 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 member (204, 208) has enough time to pass through the spiral ramp 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 it is further preferred that 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 Fig.58 As in the drum coupling 143 of the embodiment 1 shown in the figure, it is further preferred that the coupling 143 includes a driving force receiving portion 143b and a braking force receiving portion 183c at two positions 180° apart, because then the engagement state of the drive transmission unit 203 with the coupling 143 and the transmission state of the driving force are 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 easy to maintain the balance of the force applied to the coupling 143.

[0728] In addition, in the drum coupling 143 (see Figure 1), each formed 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, Figure 104 to Figure 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 be advanced and retracted in the radial direction. Fig.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 Fig.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 pushed inwardly in the radial direction by the tension spring 200.

[0731] Therefore, when the box is not used, such as Fig.104 Part (a) and Fig.104 As shown in part (c), the two engaging portions 243i are retracted into the drum coupling. On the other hand, when the cartridge is mounted to the imaging device main assembly, the positioning boss 180i enters the interior of the drum coupling and contacts the engaging portion 243i, as shown in FIG. Fig.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. Fig.104 Part (b) and Fig.104 As shown in part (d) of the embodiment, 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, namely, 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 main assembly of the image forming apparatus, 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 that is susceptible to external impact is retracted to be protected.

[0734] When a part of the coupling 143 is movable, the state in which the coupling is actually used, that is, the 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 part can be constructed to satisfy the desired conditions as described above.

[0735] also, Fig.107 and Fig.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. Fig.105 ), the engaging portion 243i is constructed to move in the radial direction, but in this modified example, the engaging portion 643i is constructed to move in the axial direction. Fig.107 Part (a) shows a state where the engaging portion 643i is retracted into the inside of the drum coupling, and Fig.107 Part (b) shows the engaging portion 643i moving toward the outside of the drum coupling and away from the photosensitive drum. Fig.107 Part (c) is an exploded perspective view of the drum unit in this modified example.

[0736] Fig.108 Parts 108 (a) and 108 (b) show cross-sectional views of the drum unit. Fig.108 Part (a) shows the state before the drum unit is mounted to the apparatus main assembly, and Fig.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. Fig.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 ( Fig.107 Part (a) and Fig.108 The portion (a)) is changed to the bonding portion 643i partially exposed to the outside ( Fig.107 sections (b) and 108(b)).

[0738] When a part of the drum coupling is movably provided in this manner, the moving direction may be a radial direction or an axial direction.A part 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 Fig.109 and Fig.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] Fig.109 Part (a) is an exploded perspective view of the drum unit of this modified example. Fig.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 main assembly of the apparatus, the engaging portion 1043i is in a state as shown in FIG. Fig.109 On the other hand, after the drum unit is mounted to the main assembly of the apparatus, the engaging portion 1043i becomes as shown in the protruding (advanced) state. Fig.109 The retracted state shown in part (c).

[0742] Fig.110 Part (a) and Fig.110 Part (b) shows a cross-sectional view of the drum unit. Fig.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 Fig.109 As shown in part (a), the engaging member 1043 is arranged 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 pressurized coil spring 1020 arranged 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. Fig.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 above three modified examples, the acting portion capable of receiving an action from the outside of the box 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 at a place other than the inside of the coupling 143.

[0746] As described above, the shape and form of the coupling may be selected according to design factors for arrangement, manufacturing factors considering 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 a drum holding unit 108 (see Fig.19 ) structure.

[0749] Furthermore, in Embodiment 1 and its various modified examples, the drum coupling 143 is placed near one end (end on the driving 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 driving 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 way, the gear of the coupling 143 and the gear of the photosensitive drum 104 can directly mesh 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 arranged separately from each other 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 a box or 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 Fig.82 , the overall structure of an electrophotographic image forming apparatus 800 (hereinafter, image forming apparatus 800) according to the present embodiment will be described. Fig.82 701 and 713 are schematic diagrams of an image forming apparatus 800 according to the present embodiment. In the present embodiment, a process cartridge 701 and a toner cartridge 713 are attachable to and detachable from a main assembly of the image forming apparatus 800.

[0763] In this embodiment, except for the different colors of the images formed, the structures and operations of the first to fourth imaging parts are substantially the same. Therefore, in the following, if no special distinction is required, the subscripts Y to K will be omitted for general description.

[0764] The first to fourth process boxes 701 are arranged side by side in the horizontal direction. Each process box 701 includes a cleaning unit 704 and a developing unit 706. The cleaning unit 704 includes a photosensitive drum 707 as an image bearing member, a charging roller 708 as a charging device for uniformly charging the surface of the photosensitive drum 707, and a cleaning blade 710 as a cleaning device. The developing unit 706 includes a developing roller 711 and accommodates a developer T (hereinafter referred to as a toner), and includes a developing device for developing an electrostatic latent image on the photosensitive drum 707. The cleaning unit 704 and the developing unit 706 are supported to be swingable relative to each other. The first process box 701Y ...

Claims

1. A cartridge which can be detachably mounted 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 include: 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