Developing cartridge

Abstract

Provided is a developing cartridge having a novel structure in which a rod cover can be attached to a bearing. The developing cartridge includes: a developing roller extending in a first direction; a housing capable of accommodating the developer, the developing roller being located at one end of the housing in a second direction intersecting the first direction; a bearing attached to one end of the housing in the first direction and supporting the developing roller; a lever which is positioned at one end of the housing in the first direction, extends in a third direction intersecting the first direction and the second direction, and is movable relative to the housing; and a rod cover attached to one end of the housing in the first direction, the rod being held between the rod cover and the bearing, the bearing having a protrusion protruding in a direction intersecting the first direction, and the rod cover having a hole into which the protrusion is inserted.

Description

Technical Field

[0001] The present utility model relates to a developing cartridge. Background Art

[0002] Conventionally, electrophotographic image forming apparatuses such as laser printers and LED printers have been known. The image forming apparatus uses a developing cartridge. The developing cartridge has a developing roller for supplying a developer. For example, Patent Document 1 describes a conventional image forming apparatus.

[0003] The developing cartridge of Patent Document 1 is mounted relative to a drum cartridge. The drum cartridge has a photosensitive drum. When the developing cartridge is mounted to the drum cartridge, the photosensitive drum comes into contact with the developing cartridge. And, the drum cartridge with the developing cartridge mounted thereon is mounted to the image forming apparatus.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2022-117103.

[0007] There are cases where the image forming apparatus performs a so-called separation operation of temporarily separating the developing roller from the photosensitive drum. In addition, there are cases where the developing cartridge has a rod that receives a driving force from the image forming apparatus during the separation operation. The rod is movable relative to the housing of the developing cartridge. In this case, the developing cartridge has a rod cover that covers a part of the rod.

[0008] The rod cover engages with a bearing mounted on the housing of the developing cartridge. Specifically, a convex portion provided on the rod cover is inserted into a concave portion provided in the bearing. However, a new structure that can mount the rod cover relative to the bearing is required. Summary of the Utility Model

[0009] An object of the present utility model is to provide a developing cartridge having a new structure capable of mounting a rod cover to a bearing.

[0010] A first aspect of the present application is characterized in that a developing cartridge includes: a developing roller extending in a first direction; a housing capable of accommodating a developer, the developing roller being located at one end of the housing in a second direction intersecting the first direction; a bearing mounted at one end portion of the housing in the first direction and supporting the developing roller; a rod located at one end portion of the housing in the first direction, extending in a third direction intersecting the first direction and the second direction, and movable relative to the housing; and a rod cover mounted at one end portion of the housing in the first direction, holding the rod between the rod cover and the bearing, the bearing having a protrusion protruding in a direction intersecting the first direction, and the rod cover having a hole into which the protrusion is inserted.

[0011] The feature of the second mode of the present application is that in the developing cartridge of the first mode, the hole is a through-hole that penetrates the rod cover.

[0012] The feature of the third mode of the present application is that in the developing cartridge of the second mode, the protrusion extends along the third direction, and the hole penetrates the rod cover along the third direction.

[0013] The feature of the fourth mode of the present application is that in the developing cartridge of any one of the first to third modes, a first screw is further provided, and the first screw fixes the rod cover to the housing.

[0014] The feature of the fifth mode of the present application is that in the developing cartridge of the fourth mode, the rod is located between the hole and the first screw in the second direction.

[0015] The feature of the sixth mode of the present application is that in the developing cartridge of any one of the first to fifth modes, the housing has a first protrusion extending along the first direction, and the rod cover has an insertion hole for inserting the first protrusion.

[0016] The feature of the seventh mode of the present application is that in the developing cartridge of the sixth mode, the hole is located at one end of the rod cover in the second direction, and the insertion hole is located at the other end of the rod cover in the second direction.

[0017] An eighth aspect of the present application is characterized in that a developing cartridge includes: a developing roller extending in a first direction; a housing capable of accommodating a developer, the developing roller being located at one end of the housing in a second direction intersecting the first direction; a bearing mounted at one end of the housing in the first direction and supporting the developing roller; a rod located at one end of the housing in the first direction, extending in a third direction intersecting the first direction and the second direction, and being movable relative to the housing; and a rod cover mounted at one end of the housing in the first direction, holding the rod between the rod cover and the bearing. The bearing has: a first engaging plate intersecting the first direction; a first arm extending in the first direction away from the rod cover from an end of the first engaging plate in the second direction that is far from the developing roller among the two ends in the second direction; and a second arm extending in the first direction away from the rod cover from an end of the first engaging plate in the third direction that intersects the first direction and the second direction and is far from the rod among the two ends in the third direction. The rod cover has: a second engaging plate intersecting the first direction; a third arm extending in the first direction away from the bearing from an end of the second engaging plate in the second direction that is close to the developing roller among the two ends in the second direction; and a fourth arm extending in the first direction away from the bearing from an end of the second engaging plate in the third direction that is far from the rod among the two ends in the third direction. Surfaces of the two surfaces of the first engaging plate in the first direction that are close to the first arm and the second arm and surfaces of the two surfaces of the second engaging plate in the first direction that are close to the third arm and the fourth arm face each other in the first direction.

[0018] A ninth aspect of the present application is characterized in that in the developing cartridge according to the eighth aspect, a first screw is further included, and the first screw fixes the rod cover to the housing.

[0019] A tenth aspect of the present application is characterized in that in the developing cartridge according to the ninth aspect, the rod is located between the second engaging plate and the first screw in the second direction.

[0020] An eleventh aspect of the present application is characterized in that in the developing cartridge according to any one of the eighth aspect to the tenth aspect, the housing has a first protrusion extending in the first direction, and the rod cover has an insertion hole into which the first protrusion is inserted.

[0021] The twelfth aspect of the present application is characterized in that, in the developing cartridge of the eleventh aspect, the second engaging plate is located at one end of the rod cover in the second direction, and the insertion hole is located at the other end of the rod cover in the second direction.

[0022] The thirteenth aspect of the present application is characterized in that, in the developing cartridge of any one of the first to twelfth aspects, a second screw is further provided, and the second screw fixes the bearing to the housing.

[0023] The fourteenth aspect of the present application is characterized in that, in the developing cartridge of any one of the first to thirteenth aspects, the housing has: a filling hole for filling a developer; and a cover that covers the filling hole, and the rod cover covers the filling hole and the cover.

[0024] The fifteenth aspect of the present application is characterized in that, in the developing cartridge of any one of the first to fourteenth aspects, the bearing is made of a conductive resin.

[0025] The sixteenth aspect of the present application is characterized in that, in the developing cartridge of any one of the first to fifteenth aspects, a supply roller is further provided, the supply roller extends along the first direction and contacts the developing roller, and the bearing supports the supply roller.

[0026] The seventeenth aspect of the present application is characterized in that, in the developing cartridge of any one of the first to sixteenth aspects, a second protrusion is further provided, the second protrusion can move together with the housing, the second protrusion extends along the second direction, the rod has: one end, which is one end of the rod and functions as a force application point; the other end, which is the other end of the rod and functions as an action point; a shaft portion, which is located between the one end and the other end and functions as a fulcrum; and a first hole for the second protrusion to be inserted into, the rod can rotate around the shaft portion by receiving a driving force at the one end, the dimension of the first hole in the second direction is larger than the dimension of the second protrusion in the second direction, and when the housing moves relative to the rod in the second direction, the second protrusion moves in the second direction inside the first hole.

[0027] The eighteenth aspect of the present application is characterized in that, in the developing cartridge of the seventeenth aspect, the developing cartridge is used together with a drum cartridge, the drum cartridge has: a photosensitive drum; and a drum frame that can mount the developing cartridge, and when the developing cartridge is mounted on the drum frame, when a driving force is applied to the one end, the rod rotates around the shaft portion, and the other end presses the housing, so that the housing moves relative to the rod in the second direction and away from the photosensitive drum.

[0028] According to the first aspect of the present application, by inserting the protrusion of the bearing into the hole of the rod cover, the detachment of the rod cover from the bearing in the first direction can be suppressed. Thus, the rod cover can be mounted on the bearing.

[0029] According to the eighth aspect of the present application, by engaging the first engaging plate of the bearing with the second engaging plate of the rod cover, the detachment of the rod cover from the bearing in the first direction can be suppressed. Thus, the rod cover can be mounted on the bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a perspective view of the developing cartridge and the drum cartridge.

[0031] Figure 2 It is a perspective view of the developing cartridge.

[0032] Figure 3 It is a cross-sectional view of the developing cartridge.

[0033] Figure 4 It is a view of the developing cartridge observed from the first outer surface side.

[0034] Figure 5 It is a perspective view near the first outer surface of the developing cartridge.

[0035] Figure 6 It is an exploded perspective view near the first outer surface of the developing cartridge.

[0036] Figure 7 It is a perspective view of the first rod.

[0037] Figure 8 It is a perspective view of the bearing.

[0038] Figure 9 It is a perspective view of the rod cover.

[0039] Figure 10 It is a view of the developing cartridge and the drum cartridge observed in the first direction.

[0040] Figure 11 It is cut by a plane orthogonal to the first direction Figure 10 of the developing cartridge and the drum cartridge.

[0041] Figure 12 It is a view of the developing cartridge and the photosensitive drum observed in the first direction when the separation operation is not performed.

[0042] Figure 13 It is a view of the developing cartridge and the photosensitive drum observed in the first direction when the separation operation is performed.

[0043] Figure 14 It is a cross-sectional view of the developing cartridge and the drum cartridge cut by a plane orthogonal to the first direction when the separation operation is performed.

[0044] Figure 15 It is a perspective view of the bearing of the second embodiment.

[0045] Figure 16 It is a perspective view of the rod cover of the second embodiment. Specific Embodiments

[0046] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0047] In addition, hereinafter, the direction in which the developing roller extends will be referred to as the "first direction". Further, the direction in which one end of the housing where the developing roller is located and the other end of the housing are arranged will be referred to as the "second direction". The first direction and the second direction intersect each other (preferably orthogonally).

[0048] <1. First Embodiment>

[0049] <1-1. Outline of Developing Cartridge and Drum Cartridge>

[0050] First, a first embodiment of the present invention will be described. Figure 1 It is a perspective view of the developing cartridge 1 and the drum cartridge 2 of the first embodiment. The developing cartridge 1 and the drum cartridge 2 are used for an electrophotographic image forming apparatus. The image forming apparatus is, for example, a laser printer or an LED printer.

[0051] As Figure 1 shown, the developing cartridge 1 is used together with the drum cartridge 2 having the photosensitive drum 92. The developing cartridge 1 can be mounted on the drum cartridge 2. Further, the developing cartridge 1 is mounted on the image forming apparatus in a state of being mounted on the drum cartridge 2. The image forming apparatus can mount, for example, four developing cartridges 1. The four developing cartridges 1 contain developers of different colors (for example, various colors such as cyan, magenta, yellow, and black). The developer is, for example, toner. The image forming apparatus forms an image on the surface of the printing paper using the developer supplied from the developing cartridge 1. However, the number of developing cartridges 1 that can be mounted on the image forming apparatus may also be one to three, or five or more.

[0052] <1-2. Regarding the Developing Cartridge>

[0053] Figure 2 It is a perspective view of the developing cartridge 1. Figure 3 It is a cross-sectional view of the developing cartridge 1 cut along a plane orthogonal to the first direction. Figure 4 It is a view of the developing cartridge 1 as viewed from the side of the first outer surface 11 described later. As Figures 2 to 4 shown, the developing cartridge 1 includes a housing 10, an agitator 20, a developing roller 30, a supply roller 40, a gear portion 50, and a first rod 60.

[0054] The housing 10 is a frame capable of accommodating a developer. The housing 10 has a first outer surface 11 and a second outer surface 12. The first outer surface 11 is located at one end of the housing 10 in the first direction. The second outer surface 12 is located at the other end of the housing 10 in the first direction. The first outer surface 11 and the second outer surface 12 are separated from each other in the first direction. The housing 10 extends in the first direction between the first outer surface 11 and the second outer surface 12, and also extends in the second direction.

[0055] An accommodation chamber 13 is provided inside the housing 10. The developer is accommodated in the accommodation chamber 13. In addition, the housing 10 has an opening 14. The opening 14 is located at one end of the housing 10 in the second direction. The external space of the housing 10 and the accommodation chamber 13 communicate with each other through the opening 14. In addition, the housing 10 may have a handle on the outer surface at the other end in the second direction.

[0056] The agitator 20 has an agitator shaft 21 and blades 22. The agitator shaft 21 extends in the first direction. The blades 22 extend from the agitator shaft 21 toward the inner surface of the housing 10. That is, the blades 22 extend from the agitator shaft 21 toward the radially outer side. A part of the agitator shaft 21 and the blades 22 are located in the accommodation chamber 13 of the housing 10. The end of the agitator shaft 21 in the first direction is fixed to the agitator gear included in the gear unit 50. When the agitator gear rotates, the agitator shaft 21 and the blades 22 rotate around the rotation axis extending in the first direction. Then, by the rotation of the blades 22, the developer in the accommodation chamber 13 is agitated.

[0057] The developing roller 30 is a roller capable of rotating around the rotation axis extending in the first direction. The developing roller 30 is located at the opening 14 of the housing 10. That is, the developing roller 30 is located at one end of the housing 10 in the second direction. The developing roller 30 has a developing roller body 31 and a developing roller shaft 32. The developing roller body 31 is a cylindrical member extending in the first direction. The material of the developing roller body 31 uses, for example, elastic rubber. The developing roller shaft 32 is a cylindrical member that penetrates the developing roller body 31 and extends in the first direction. The developing roller body 31 is fixed relative to the developing roller shaft 32. The developing roller shaft 32 is conductive. The material of the developing roller shaft 32 uses metal or conductive resin.

[0058] The developing cartridge 1 has a bearing 80. The bearing 80 is installed at one end of the housing 10 in the first direction. Specifically, the bearing 80 is fixed to the first outer surface 11 of the housing 10 by screws 83. The screws 83 are an example of the "second screws". The bearing 80 is plate-shaped and extends along the first outer surface 11. The bearing 80 is conductive. The material of the bearing 80 uses metal or conductive resin.

[0059] One end of the developing roller shaft 32 in the first direction is supported by the bearing 80. Specifically, one end of the developing roller shaft 32 in the first direction is inserted into a first through hole (not shown) provided in the bearing 80. In addition, one end of the developing roller shaft 32 in the first direction contacts the bearing 80. Therefore, the developing roller shaft 32 is electrically connected to the bearing 80.

[0060] When the drum cartridge 2 equipped with the developing cartridge 1 is installed in the image forming apparatus, the image forming apparatus supplies a bias voltage to the developing roller shaft 32 via the bearing 80. Then, due to the electrostatic force between the developing roller shaft 32 and the developer, the developer is carried on the outer peripheral surface of the developing roller main body 31.

[0061] The other end of the developing roller shaft 32 in the first direction is fixed to the developing roller gear included in the gear unit 50. Therefore, when the developing roller gear rotates, the developing roller shaft 32 also rotates, and the developing roller main body 31 also rotates together with the developing roller shaft 32.

[0062] In addition, the developing roller shaft 32 may not penetrate the developing roller main body 31 in the first direction. For example, the developing roller shaft 32 may include a first developing roller shaft extending in the first direction from one end of the developing roller main body 31 in the first direction and a second developing roller shaft extending in the first direction from the other end of the developing roller main body 31 in the first direction.

[0063] The supply roller 40 is a roller that can rotate about a rotation axis extending in the first direction. The supply roller 40 is located between the agitator 20 and the developing roller 30. The supply roller 40 has a supply roller main body 41 and a supply roller shaft 42. The supply roller main body 41 is a cylindrical member extending in the first direction. The material of the supply roller main body 41 uses, for example, elastic rubber. The supply roller shaft 42 is a cylindrical member that penetrates the supply roller main body 41 and extends in the first direction. The supply roller main body 41 is fixed relative to the supply roller shaft 42. The supply roller shaft 42 is conductive. The material of the supply roller shaft 42 uses metal or conductive resin.

[0064] One end of the supply roller shaft 42 in the first direction is supported by the bearing 80. Specifically, one end of the supply roller shaft 42 in the first direction is inserted into a second through hole (not shown) provided in the bearing 80. In addition, one end of the supply roller shaft 42 in the first direction contacts the bearing 80. Therefore, the supply roller shaft 42 is electrically connected to the bearing 80.

[0065] When the drum cartridge 2 equipped with the developing cartridge 1 is installed in the image forming apparatus, the image forming apparatus supplies a bias voltage to the supply roller shaft 42 via the bearing 80. Then, due to the electrostatic force between the supply roller shaft 42 and the developer, the developer is carried on the outer peripheral surface of the supply roller main body 41.

[0066] The other end of the supply roller shaft 42 in the first direction is fixed to the supply roller gear included in the gear unit 50. Therefore, when the supply roller gear rotates, the supply roller shaft 42 also rotates, and the supply roller main body 41 also rotates together with the supply roller shaft 42.

[0067] In addition, the supply roller shaft 42 may not penetrate the supply roller main body 41 in the first direction. For example, the supply roller shaft 42 may include a first supply roller shaft extending in the first direction from one end of the supply roller main body 41 in the first direction and a second supply roller shaft extending in the first direction from the other end of the supply roller main body 41 in the first direction.

[0068] The outer peripheral surface of the developing roller main body 31 is in contact with the outer peripheral surface of the supply roller main body 41. The developer in the housing 10 is supplied to the developing roller 30 via the supply roller 40. In addition, the developing cartridge 1 has a layer thickness limiting blade 35. The layer thickness limiting blade 35 forms the developer carried on the outer peripheral surface of the developing roller main body 31 into a constant thickness. Subsequently, the developer on the outer peripheral surface of the developing roller main body 31 is supplied to the photosensitive drum 92 described later in the drum cartridge 2. At this time, the developer moves from the developing roller main body 31 to the photosensitive drum 92 according to the electrostatic latent image formed on the outer peripheral surface of the photosensitive drum 92. Thus, the electrostatic latent image is visualized on the outer peripheral surface of the photosensitive drum 92.

[0069] The gear unit 50 is located on the second outer surface 12 of the housing 10. The gear unit 50 has a gear cover 51, a coupling, and a plurality of gears. The gear cover 51 and the housing 10 together form the frame of the developing cartridge 1. The gear cover 51 is fixed to the second outer surface 12 of the housing 10. The plurality of gears includes the above-described agitator gear, developing roller gear, and supply roller gear. At least a part of the plurality of gears is located between the second outer surface 12 and the gear cover 51.

[0070] The coupling projects from the gear cover 51. When the developing cartridge 1 mounted on the drum cartridge 2 is mounted on the image forming apparatus, the drive shaft of the image forming apparatus is connected to the coupling. And the rotation of the drive shaft is transmitted to the agitator gear, developing roller gear, and supply roller gear via the coupling.

[0071] In addition, the plurality of gears included in the gear unit 50 may transmit the rotational force by meshing of teeth or may transmit the rotational force by friction.

[0072] The first lever 60 is located on the first outer surface 11 of the housing 10. The first lever 60 is provided separately from the developing roller 30 in the second direction. The first lever 60 is movable relative to the housing 10. The first lever 60 is an example of a "lever".

[0073] Figure 5 It is a perspective view near the first outer surface 11 of the developing cartridge 1. Figure 6 It is an exploded perspective view near the first outer surface of the developing cartridge 1. Figure 7It is a perspective view of the first rod 60. As Figures 4 to 7 shown, the first rod 60 has one end 61, the other end 62, a shaft portion 63, and a first hole 64. The first rod 60 extends in a third direction that intersects the first direction and the second direction. One end 61 is located at one end of the first rod 60 in the third direction. The other end 62 is located at the other end of the first rod 60 in the third direction. One end 61 and the other end 62 are separated in the third direction.

[0074] One end 61 of the first rod 60 has a first convex portion 65. The first convex portion 65 protrudes in the first direction from one end 61 of the first rod 60. In addition, the first convex portion 65 protrudes in a direction away from the first outer surface 11 of the housing 10 at one end 61 of the first rod 60. The first convex portion 65 has a concave surface 66. In a state where the developing cartridge 1 is mounted on the drum cartridge 2, the concave surface 66 is recessed toward a later-described photosensitive drum 92 of the drum cartridge 2.

[0075] The other end 62 of the first rod 60 has a second convex portion 67. The second convex portion 67 protrudes in the first direction from the other end 62 of the first rod 60. In addition, the second convex portion 67 protrudes toward the first outer surface 11 of the housing 10 at the other end 62 of the first rod 60.

[0076] The shaft portion 63 is located between one end 61 and the other end 62 in the third direction. The shaft portion 63 protrudes from the first rod 60 in the first direction. In addition, the shaft portion 63 protrudes in a direction away from the first outer surface 11 of the housing 10. In a state where the developing cartridge 1 is mounted on the drum cartridge 2, the shaft portion 63 can contact a later-described drum frame 91 of the drum cartridge 2. And the first rod 60 can rotate between a first position and a second position about the shaft portion 63.

[0077] As Figures 4 to 6 shown, the housing 10 has a pressing receiving surface 16. The pressing receiving surface 16 is located at a position farther from the developing roller 30 than the other end 62 of the first rod 60 in the second direction. In addition, the pressing receiving surface 16 faces the other end 62 of the first rod 60 in the second direction. Specifically, the pressing receiving surface 16 faces the second convex portion 67 of the first rod 60 in the second direction.

[0078] In a state where the developing cartridge 1 is mounted on the drum cartridge 2, when one end 61 of the first rod 60 receives a driving force from the image forming apparatus, the first rod 60 rotates about the shaft portion 63. As a result, the other end 62 of the first rod 60 contacts the pressing receiving surface 16. At this time, the shaft portion 63 of the first rod 60 functions as a fulcrum. One end 61 of the first rod 60 functions as a force receiving point. The other end 62 of the first rod 60 functions as a point of action.

[0079] The first hole 64 is located between one end portion 61 and the other end portion 62 in the third direction. The first hole 64 overlaps with the shaft portion 63 in the first direction. The first hole 64 is recessed from the surface of the first rod 60 facing the housing 10 toward the shaft portion 63 in the first direction. In the present embodiment, the shape of the first hole 64 is a circle centered on an axis extending in the first direction. However, the first hole 64 may also be a shape other than a circle, such as an ellipse or a polygon.

[0080] As Figure 5 shown, the bearing 80 has a protrusion 81. The protrusion 81 is an example of a "second protrusion". The protrusion 81 extends from the surface of the bearing 80 facing the first rod 60 toward the first rod 60 in the first direction. The bearing 80 is fixed to the housing 10. Therefore, the protrusion 81 can move together with the housing 10.

[0081] The protrusion 81 is inserted into the first hole 64 of the first rod 60. The inner diameter of the first hole 64 is larger than the outer diameter of the protrusion 81. That is, the dimension of the first hole 64 in the second direction is larger than the dimension of the protrusion 81 in the second direction. In addition, the dimension of the first hole 64 in the third direction is larger than the dimension of the protrusion 81 in the third direction. Therefore, the first hole 64 can move relative to the protrusion 81 in the second direction and the third direction. In addition, the first rod 60 can move relative to the bearing 80 and the housing 10 in the second direction and the third direction within the range of the dimensional difference between the protrusion 81 and the first hole 64.

[0082] In addition, as Figure 5 and Figure 6 shown, the first rod 60 has a protrusion 68. The protrusion 68 protrudes from the periphery of the first hole 64 toward the other end in the second direction of the housing 10. On the other hand, as Figure 6 shown, the housing 10 has a pressing surface 15. The protrusion 68 and the pressing surface 15 face each other in the rotational direction centered on the developing roller 30.

[0083] In addition, the developing cartridge 1 has a rod cover 70. The rod cover 70 is attached to one end portion of the housing 10 in the first direction. More specifically, the rod cover 70 is fixed to the first outer surface 11 of the housing 10. The rod cover 70 covers a part of the first rod 60. That is, a part of the first rod 60 is located between the first outer surface 11 of the housing 10 and the rod cover 70. In addition, the rod cover 70 is located between the first convex portion 65 and the second convex portion 67 of the first rod 60 in the third direction. The first convex portion 65 and the rod cover 70 face each other in the third direction and can come into contact with each other. Thereby, the first rod 60 is prevented from coming off from the rod cover 70 in the third direction. That is, the rod cover 70 holds the first rod 60 in a state capable of moving relative to the housing 10 between the rod cover 70 and the bearing 80.

[0084] As Figure 6As shown, the housing 10 has a filling hole 17 and a cover 18. The filling hole 17 is a hole for filling the developing agent into the accommodating chamber 13 of the housing 10. The filling hole 17 is located on the first outer surface 11 of the housing 10. Specifically, the filling hole 17 penetrates the first outer surface 11 of the housing 10 in the first direction. The shape of the filling hole 17 when viewed from the first direction is circular. The cover 18 is a cover that covers the filling hole 17. The cover 18 can be attached to and detached from the filling hole 17.

[0085] The rod cover 70 has a cover portion 71. The cover portion 71 extends in a direction intersecting the first direction. The filling hole 17 and the cover 18 are covered by the cover portion 71. That is, the filling hole 17 and the cover 18 are located between the accommodating chamber 13 and the cover portion 71 in the first direction.

[0086] <1-3. Mounting Structure of Rod Cover>

[0087] Next, the mounting structure of the rod cover 70 with respect to the housing 10 and the bearing 80 will be described.

[0088] Figure 8 is a perspective view of the bearing 80. As Figure 8 shown, the bearing 80 has a hook 82. The hook 82 is located at one end of the bearing 80 in the third direction. The hook 82 is located closer to the one end 61 than the other end 62 of the first rod 60 in the third direction.

[0089] The hook 82 has an arm 821 and a protrusion 822. The arm 821 extends in the first direction from the outer surface of the bearing 80 in the first direction toward the rod cover 70. The protrusion 822 protrudes in a direction intersecting the first direction from the tip of the arm 821 in the first direction. Specifically, the protrusion 822 protrudes from the tip of the arm 821 in the first direction toward the third direction. More specifically, the protrusion 822 protrudes in the third direction from the tip of the arm 821 in the first direction away from the other end 62 of the first rod 60.

[0090] Figure 9 is a perspective view of the rod cover 70. As Figure 9 shown, the rod cover 70 has a hole 72. The hole 72 is located at one end of the rod cover 70 in the second direction. The hole 72 is a through hole that penetrates one end of the rod cover 70 in the second direction. More specifically, the hole 72 penetrates one end of the rod cover 70 in the second direction in the third direction. The protrusion 822 of the bearing 80 is inserted into the hole 72 of the rod cover 70. Thereby, it is possible to prevent the rod cover 70 from coming off the bearing 80 in the first direction. In addition, by providing the hole 72 in the rod cover 70 instead of the bearing 80, the hole 72 can be made larger. Therefore, the rod cover 70 can be easily mounted with respect to the bearing 80.

[0091] However, the hole 72 of the rod cover 70 does not have to be a through hole either. The hole 72 of the rod cover 70 can also be a recess capable of inserting the protrusion 822.

[0092] In addition, as Figure 6 shown, the housing 10 has a protrusion 19. The protrusion 19 is an example of a "first protrusion". The protrusion 19 is a protrusion extending in the first direction. Specifically, the protrusion 19 extends from the first outer surface 11 of the housing 10 toward the rod cover 70 in the first direction. On the other hand, the rod cover 70 has an insertion hole 73. The insertion hole 73 is located at the other end of the rod cover 70 in the second direction. The insertion hole 73 penetrates the other end of the rod cover 70 in the second direction in the first direction. The protrusion 19 is inserted into the insertion hole 73. Thus, the position of the rod cover 70 relative to the housing 10 is restricted.

[0093] When manufacturing the developing cartridge 1, first, the bearing 80 is mounted on the housing 10. Specifically, the bearing 80 is disposed on the first outer surface 11 of the housing 10, and the bearing 80 is fixed to the first outer surface 11 by screws 83.

[0094] Next, with the first rod 60 disposed between the bearing 80 and the rod cover 70, the rod cover 70 is mounted on the housing 10 and the bearing 80. Specifically, first, the protrusion 19 of the housing 10 is inserted into the insertion hole 73 of the rod cover 70. Thus, the movement of the rod cover 70 relative to the housing 10 in the direction perpendicular to the first direction is restricted. However, the rotation of the rod cover 70 about the protrusion 19 is allowed.

[0095] Next, the protrusion 822 of the bearing 80 is inserted into the hole 72 of the rod cover 70. The protrusion 822 extends along the rotation direction of the rod cover 70 about the protrusion 19. In addition, the hole 72 penetrates the rod cover 70 along the rotation direction of the rod cover 70 about the protrusion 19. Therefore, by rotating the rod cover 70 about the protrusion 19, the protrusion 822 can be easily inserted into the hole 72.

[0096] By inserting the protrusion 822 into the hole 72, the rotation of the rod cover 70 about the protrusion 19 stops. In addition, by inserting the protrusion 822 into the hole 72, the rod cover 70 can be prevented from moving relative to the housing 10 and the bearing 80 in the first direction. That is, the rod cover 70 is prevented from coming off relative to the housing 10 and the bearing 80 in the first direction.

[0097] Subsequently, the rod cover 70 is fixed to the housing 10 by screws 74. The screws 74 are an example of "first screws". The screws 74 are located between the hole 72 and the insertion hole 73 in the second direction. In addition, the first rod 60 is located between the hole 72 and the screws 74 in the second direction.

[0098] <1 - 4. Regarding the drum cartridge>

[0099] Next, the drum cartridge 2 will be described. Figure 10 It is a view of observing the developing cartridge 1 and the drum cartridge 2 in the first direction. Figure 11 It is a cross-sectional view of the developing cartridge 1 and the drum cartridge 2 cut along a plane orthogonal to the first direction. Figure 10

[0100] As Figure 1 shown, the drum cartridge 2 has a drum frame 91 and a photosensitive drum 92. The developing cartridge 1 is mounted on the drum frame 91. The photosensitive drum 92 is a cylindrical member that can rotate about a rotation axis extending in the first direction. The outer peripheral surface of the photosensitive drum 92 is covered with a photosensitive material. The photosensitive drum 92 is located at one end of the drum frame 91 in the second direction. When the developing cartridge 1 is mounted on the drum frame 91, the outer peripheral surface of the developing roller 30 contacts the outer peripheral surface of the photosensitive drum 92. At this time, the developing roller 30 is pressed toward the photosensitive drum 92 in the second direction by an elastic member 93 provided in the drum cartridge 2.

[0101] As Figure 1 and Figure 10 shown, the drum frame 91 has a recess 911. The recess 911 is located at one end of the drum frame 91 in the first direction. The recess 911 is recessed toward the photosensitive drum 92 in the second direction. When the developing cartridge 1 is mounted on the drum cartridge 2, the shaft portion 63 of the first rod 60 is inserted into the recess 911. And, the shaft portion 63 contacts the recess 911 in the direction toward the photosensitive drum 92.

[0102] In addition, as Figure 10 shown, the drum frame 91 has a guide surface 912. The guide surface 912 is located at one end of the drum frame 91 in the first direction. In addition, the guide surface 912 is located beside the recess 911. The guide surface 912 is inclined with respect to the rotation direction centered on the developing roller 30. When the developing cartridge 1 is being mounted on the drum cartridge 2, the guide surface 912 guides the shaft portion 63 of the first rod 60 toward the recess 911.

[0103] <1-5. Installation operation of the developing cartridge>

[0104] When the developing cartridge 1 is mounted on the drum cartridge 2, the developing cartridge 1 moves relative to the drum cartridge 2. As a result, the developing roller 30 approaches the photosensitive drum 92. At this time, the shaft portion 63 of the first rod 60 contacts the guide surface 912 of the drum frame 91. And, in a state where the shaft portion 63 contacts the guide surface 912, the outer peripheral surface of the developing cartridge 1 contacts the outer peripheral surface of the photosensitive drum 92.

[0105] Subsequently, while maintaining the state where the developing roller 30 is in contact with the photosensitive drum 92, the housing 10 of the developing cartridge 1 is rotated about the developing roller 30. Specifically, the housing 10 is rotated about the developing roller 30 in a direction approaching the drum frame 91. At this time, the pressing surface 15 of the housing 10 comes into contact with the projection 68 of the first lever 60. And as the housing 10 rotates, the pressing surface 15 presses the projection 68 toward the recess 911. As a result, the shaft portion 63 of the first lever 60 moves along the guide surface 912 toward the recess 911. As a result, as Figure 10 shown, the shaft portion 63 is disposed within the recess 911.

[0106] Thus, in the structure of the present embodiment, during the installation of the developing cartridge 1 onto the drum cartridge 2, the pressing surface 15 of the housing 10 presses the projection 68 of the first lever 60. Thereby, the shaft portion 63 of the first lever 60 can be pressed into the recess 911. In addition, the shaft portion 63 of the first lever 60 is guided toward the recess 911 along the guide surface 912 of the drum frame 91. Therefore, the shaft portion 63 of the first lever 60 can be disposed within the recess 911 with higher precision.

[0107] In addition, in the structure of the present embodiment, the projection 81 of the bearing 80 is embedded in the first hole 64 of the first lever 60. Thereby, the range in which the first lever 60 can move relative to the housing 10 is restricted. Therefore, during the installation of the developing cartridge 1 onto the drum cartridge 2, the shaft portion 63 of the first lever 60 can be brought into contact with the guide surface 912 of the drum frame 91.

[0108] In addition, the shaft portion 63 and the first hole 64 overlap in the first direction. Therefore, by the fitting of the projection 81 into the first hole 64, the movement range of the first lever 60, especially the shaft portion 63, can be restricted. Therefore, during the installation of the developing cartridge 1 onto the drum cartridge 2, the shaft portion 63 of the first lever 60 can be brought into contact with the guide surface 912 of the drum frame 91 with higher precision.

[0109] <1-6. Regarding the separation operation>

[0110] After the developing cartridge 1 is installed on the image forming apparatus in a state where it is installed on the drum cartridge 2, the separation operation can be performed by the driving force supplied from the image forming apparatus. The separation operation is an operation of temporarily separating the developing roller 30 from the photosensitive drum 92. For example, when black-and-white printing is performed in the image forming apparatus, the developing cartridges 1 of colors other than black perform the separation operation. However, there may also be a case where the black developing cartridge 1 performs the separation operation.

[0111] Figure 12 is a view of the developing cartridge 1 and the photosensitive drum 92 when the separation operation is not performed, as viewed in the first direction. Figure 13 is a view of the developing cartridge 1 and the photosensitive drum 92 when the separation operation has been performed, as viewed in the first direction. In addition, in Figure 12 and Figure 13In the figure, a part of the image forming apparatus is indicated by a double-dashed line.

[0112] As Figure 12 shown, when the developing cartridge 1 is mounted on the drum cartridge 2, the housing 10 of the developing cartridge 1 is disposed at the crimping position where the developing roller 30 contacts the photosensitive drum 92. The position of the first lever 60 at this time is the first position. At the first position, the other end 62 of the first lever 60 is separated from the pressing receiving surface 16. Therefore, the other end 62 of the first lever 60 does not press the pressing receiving surface 16. In addition, the shaft portion 63 of the first lever 60 contacts the concave portion 911 of the drum frame 91.

[0113] When the image forming apparatus performs the separation operation, a driving force is applied to one end 61 of the first lever 60. Specifically, as Figure 12 and Figure 13 shown, the image forming apparatus has a main body cam 101. The main body cam 101 can move in the second direction between a third position ( Figure 12 position) and a fourth position ( Figure 13 position) with respect to the frame of the image forming apparatus. When the image forming apparatus performs the separation operation, the main body cam 101 is moved from the third position to the fourth position.

[0114] In a state where the drum cartridge 2 on which the developing cartridge 1 is mounted is mounted on the image forming apparatus, when the main body cam 101 is in the third position, the main body cam 101 does not contact the first lever 60. On the other hand, in a state where the drum cartridge 2 on which the developing cartridge 1 is mounted is mounted on the image forming apparatus, when the main body cam 101 is in the fourth position, the main body cam 101 contacts one end 61 of the first lever 60. More specifically, the main body cam 101 contacts the concave surface 66 of the first lever 60. And, the main body cam 101 presses one end 61 of the first lever 60 toward the photosensitive drum 92 in the second direction.

[0115] Thereby, the first lever 60 rotates about the shaft portion 63 supported by the concave portion 911. That is, the first lever 60 rotates from the first position to the second position with respect to the housing 10. Then, the other end 62 of the first lever 60 contacts the pressing receiving surface 16 of the housing 10. Then, the other end 62 of the first lever 60 presses the pressing receiving surface 16 of the housing 10 in the second direction and away from the photosensitive drum 92. Thereby, the first outer surface 11 of the housing 10 moves in the second direction and away from the photosensitive drum 92 with respect to the first lever 60.

[0116] In addition, the developing cartridge 1 has a second rod (not shown). The second rod is located on the second outer surface 12 of the housing 10. When the image forming apparatus performs the separation operation, a driving force is directly applied to the second rod or applied to the second rod via a component of the drum cartridge 2. As a result, the second rod is pressed in the second direction and away from the photosensitive drum 92. As a result, the second outer surface 12 of the housing 10 moves in the second direction and away from the photosensitive drum 92.

[0117] In this way, in the first outer surface 11 of the housing 10, the main body cam 101 presses the first rod 60, and the first rod 60 presses the housing 10 away from the photosensitive drum 92. In addition, in the second outer surface 12 of the housing 10, the second rod is pressed away from the photosensitive drum 92. As a result, the housing 10 can be moved in the second direction from the crimping position where the developing roller 30 is in contact with the photosensitive drum 92 to the separation position where the developing roller 30 is separated from the photosensitive drum 92.

[0118] Figure 14 FIG. is a cross-sectional view of the developing cartridge 1 and the drum cartridge 2 when the separation operation is performed by cutting along a plane orthogonal to the first direction. In Figure 14 the position of the projection 81 when the separation operation is not performed is indicated by a two-dot chain line.

[0119] The first hole 64 of the first rod 60 is located at a position axially overlapping the shaft portion 63 which is the pivot point of the rotation of the first rod 60. Therefore, even if the first rod 60 rotates around the shaft portion 63 from the first position to the second position, the position of the first hole 64 relative to the drum frame 91 hardly changes. That is, before and after the separation operation, the position of the first hole 64 relative to the drum frame 91 hardly changes. In contrast, the projection 81 moves together with the housing 10. Therefore, by the separation operation, the position of the projection 81 relative to the drum frame 91 moves in the second direction. That is, inside the first hole 64, the projection 81 moves Figure 12 from the position of the two-dot chain line in to the position of the solid line in the second direction.

[0120] However, the difference in the dimensions of the first hole 64 and the projection 81 in the second direction is larger than the distance that the housing 10 moves in the second direction during the separation operation. Therefore, the projection 81 does not contact the first rod 60 in any state before and after the separation operation. Therefore, the housing 10 can move from the crimping position to the separation position without being hindered by the first rod 60.

[0121] <2. Second Embodiment>

[0122] Next, a second embodiment of the present invention will be described. In the second embodiment, only the mounting structure of the rod cover 70 with respect to the housing 10 and the bearing 80 is different from that of the first embodiment. Hereinafter, only the differences from the first embodiment will be described, and the description of the same points as the first embodiment will be omitted.

[0123] Figure 15 is a perspective view of the bearing 80 of the second embodiment. As Figure 15 shown, the bearing 80 of the second embodiment has a bearing hook 84. The bearing hook 84 is located at one end of the bearing 80 in the third direction. The bearing hook 84 is located closer to the one end 61 than the other end 62 of the first rod 60 in the third direction.

[0124] The bearing hook 84 has a first arm 841, a second arm 842, and a first engaging plate 843.

[0125] The first arm 841 and the second arm 842 extend along the first direction from the outer surface of the bearing 80 in the first direction toward the rod cover 70. The first engaging plate 843 projects from the tips of the first arm 841 and the second arm 842 in the first direction in a direction crossing the first direction. The first engaging plate 843 is a flat plate shape that extends in the direction crossing the first direction.

[0126] The first arm 841 extends in the first direction away from the rod cover 70 from the end of the two ends of the first engaging plate 843 in the second direction that is away from the developing roller 30. The second arm 842 extends in the first direction away from the rod cover 70 from the end of the two ends of the first engaging plate 843 in the third direction that is away from the one end 61 of the first rod 60 in the third direction. The first arm 841 and the second arm 842 are connected to each other to form a substantially L-shaped arm.

[0127] Figure 16 is a perspective view of the rod cover 70 of the second embodiment. As Figure 16 shown, the rod cover 70 has a cover hook 75. The cover hook 75 is located at one end of the rod cover 70 in the second direction. The cover hook 75 is located closer to the one end 61 than the other end 62 of the first rod 60 in the third direction.

[0128] The cover hook 75 has a third arm 751, a fourth arm 752, and a second engaging plate 753.

[0129] The third arm 751 and the fourth arm 752 extend along the first direction from the inner surface of the rod cover 70 in the first direction toward the bearing 80. The second engaging plate 753 projects from the tips of the third arm 751 and the fourth arm 752 in the first direction in a direction crossing the first direction. The second engaging plate 753 is a flat plate shape that extends in the direction crossing the first direction.

[0130] The third arm 751 extends in the first direction away from the bearing 80 from the ends of the second engaging plate 753 in the second direction that are close to the developing roller 30. The fourth arm 752 extends in the first direction away from the bearing 80 from the ends of the second engaging plate 753 in the third direction that are away from the other end 62 of the third direction that is away from the first rod 60. The third arm 751 and the fourth arm 752 are connected to each other to form an arm in a substantially L shape.

[0131] When manufacturing the developing cartridge 1, first, the bearing 80 is mounted with respect to the housing 10. Specifically, the bearing 80 is disposed on the first outer surface 11 of the housing 10, and the bearing 80 is fixed to the first outer surface 11 by screws 83.

[0132] Next, the rod cover 70 is mounted to the housing 10 and the bearing 80. Specifically, first, the projection 19 of the housing 10 is inserted into the insertion hole 73 of the rod cover 70. Thereby, the movement of the rod cover 70 with respect to the housing 10 in the direction perpendicular to the first direction is restricted. However, rotation of the rod cover 70 about the projection 19 is allowed.

[0133] Next, the bearing hook 84 is engaged with the cover hook 75. Thereby, the surfaces of the two surfaces of the first engaging plate 843 in the first direction that are close to the first arm 841 and the second arm 842 and the surfaces of the two surfaces of the second engaging plate 753 in the first direction that are close to the third arm 751 and the fourth arm 752 face each other in the first direction.

[0134] The bearing hook 84 and the cover hook 75 are engaged in the rotational direction of the rod cover 70 about the projection 19. Therefore, by rotating the rod cover 70 about the projection 19, the bearing hook 84 can be easily engaged with the cover hook 75.

[0135] By the engagement of the bearing hook 84 with the cover hook 75, the rotation of the rod cover 70 about the projection 19 stops. In addition, by the first engaging plate 843 and the second engaging plate 753 facing each other in the first direction, the movement of the rod cover 70 with respect to the housing 10 and the bearing 80 in the first direction can be prevented. That is, the rod cover 70 can be prevented from coming off with respect to the housing 10 and the bearing 80 in the first direction.

[0136] Subsequently, the rod cover 70 is fixed to the housing 10 by screws 74. The screw 74 is an example of the "first screw". The screw 74 is located between the second engaging plate 753 and the insertion hole 73 in the second direction. In addition, the first rod 60 is located between the second engaging plate 753 and the screw 74 in the second direction.

[0137] As described above, in the second embodiment, by engaging the first engaging plate 843 with the second engaging plate 753, it is possible to prevent the rod cover 70 from coming off the bearing 80 in the first direction. Further, when the first engaging plate 843 is engaged with the second engaging plate 753, two surfaces of the bearing 80 side other than the first arm 841 and the second arm 842 are open, and two surfaces of the rod cover 70 side other than the third arm 751 and the fourth arm 752 are open. That is, the bearing hook 84 is open in two directions, the second direction and the third direction, and the cover hook 75 is also open in two directions, the second direction and the third direction. Thus, it is possible to easily engage the bearing hook 84 with the cover hook 75. Therefore, it is possible to easily attach the rod cover 70 to the bearing 80.

[0138] <3. Modification Example>

[0139] The above describes an embodiment of the present invention, but the present invention is not limited to the above-described embodiment.

[0140] In the above embodiment, the protrusion 81 extends from the bearing 80. However, the protrusion 81 may also extend from the first outer surface 11 of the housing 10.

[0141] Further, in the above embodiment, the developing cartridge 1 is attached to the drum cartridge 2 having one photosensitive drum 92. However, the developing cartridge may also be attached to a drum cartridge having a plurality of photosensitive drums. Further, the developing cartridge may also be directly attached to the image forming apparatus.

[0142] Further, regarding the detailed shape of the developing cartridge 1, it may also be different from the shape shown in the respective drawings of the present application. Further, the respective elements appearing in the above-described embodiment and modification example may be appropriately combined within a range not causing any contradiction.

Claims

1. A developing box, characterized in that: have: a developing roller extending along a first direction; A housing capable of containing a developer, wherein the developing roller is located at one end of the housing in a second direction intersecting the first direction; a bearing mounted on one end portion of the housing in the first direction and supporting the developing roller; a rod located at one end of the housing in the first direction, extending in a third direction intersecting the first direction and the second direction, and movable relative to the housing; and a rod cover mounted on one end of the housing in the first direction, and holding the rod between the rod cover and the bearing, The bearing has a protrusion protruding in a direction intersecting the first direction, The rod cover has a hole into which the protrusion is inserted.

2. The developing cartridge according to claim 1, characterized in that: The hole is a through hole that penetrates the rod cover.

3. The developing cartridge according to claim 2, characterized in that: The protrusion extends along the third direction, The hole penetrates the rod cover along the third direction.

4. The developing cartridge according to claim 1, wherein: A first screw is further provided, the first screw fixing the rod cover to the housing.

5. The developing cartridge according to claim 4, characterized in that: The rod is located between the hole and the first screw in the second direction.

6. The developing cartridge according to claim 1, characterized in that: The housing has a first protrusion extending along the first direction, The rod cover has an insertion hole into which the first protrusion is inserted.

7. The developing cartridge according to claim 6, wherein: The hole is located at one end of the rod cover in the second direction. The insertion hole is located at the other end portion of the rod cover in the second direction.

8. A developing cartridge, characterized in that: have: a developing roller extending along a first direction; A housing capable of containing a developer, wherein the developing roller is located at one end of the housing in a second direction intersecting the first direction; a bearing mounted on one end portion of the housing in the first direction and supporting the developing roller; a rod located at one end of the housing in the first direction, extending in a third direction intersecting the first direction and the second direction, and movable relative to the housing; and a rod cover mounted on one end of the housing in the first direction, and holding the rod between the rod cover and the bearing, The bearing has: A first engaging plate, the first engaging plate intersecting the first direction; a first arm extending from one of the two ends of the first engaging plate in the second direction away from the developing roller in a direction away from the rod cover in the first direction; as well as a second arm extending in the first direction away from the rod cover from one end of the first engaging plate in the third direction intersecting the first direction and the second direction, out of the two ends of the first engaging plate in the third direction intersecting the first direction and the second direction and away from the end of the rod in the third direction; The rod cover has: a second engaging plate, the second engaging plate intersecting the first direction; a third arm extending from one of the two ends of the second engaging plate in the second direction, which is close to the developing roller, in a direction away from the bearing in the first direction; as well as a fourth arm extending in the first direction away from the bearing from one of the two ends of the second engaging plate in the third direction and away from the other end of the rod in the third direction, A surface close to the first arm and the second arm among the two surfaces of the first engaging plate in the first direction and a surface close to the third arm and the fourth arm among the two surfaces of the second engaging plate in the first direction are opposite in the first direction.

9. The developing cartridge according to claim 8, characterized in that: A first screw is further provided, the first screw fixing the rod cover to the housing.

10. The developing cartridge according to claim 9, characterized in that: The rod is located between the second engaging plate and the first screw in the second direction.

11. The developing cartridge according to claim 8, characterized in that: The housing has a first protrusion extending along the first direction, The rod cover has an insertion hole into which the first protrusion is inserted.

12. The developing cartridge according to claim 11, characterized in that: The second engaging plate is located at one end of the rod cover in the second direction. The insertion hole is located at the other end portion of the rod cover in the second direction.

13. The developing cartridge according to any one of claims 1 to 12, characterized in that: A second screw is further provided, the second screw fixing the bearing to the housing.

14. The developing cartridge according to any one of claims 1 to 12, characterized in that: The housing has: a filling hole for filling a developer; and a cover covering the filling hole, The rod cover covers the filling hole and the lid.

15. The developing cartridge according to any one of claims 1 to 12, characterized in that: The bearing is made of conductive resin.

16. The developing cartridge according to any one of claims 1 to 12, characterized in that: A supply roller is further provided, the supply roller extending in the first direction and contacting the developing roller, The bearing supports the supply roller.

17. The developing cartridge according to any one of claims 1 to 12, characterized in that: The housing further comprises a second protrusion, the second protrusion being movable together with the housing and extending along the second direction. The rod has: an end portion, which is one end portion of the rod and functions as a force bearing point; another end portion, which is the other end portion of the rod and functions as a point of action; a shaft portion located between the one end portion and the other end portion and functioning as a fulcrum; as well as a first hole, wherein the second protrusion is inserted into the first hole; The rod is rotatable around the shaft portion by receiving a driving force at the one end portion. The size of the first hole in the second direction is larger than the size of the second protrusion in the second direction. When the housing moves in the second direction relative to the rod, the second protrusion moves in the second direction inside the first hole.

18. The developing cartridge according to claim 17, characterized in that: The developing cartridge is used together with the drum cartridge, The drum box has: Photosensitive drum; and a drum frame capable of mounting the developing cartridge, When the developing box is installed on the drum frame, when the one end receives driving force, the rod rotates around the shaft and the other end presses the shell, so that the shell moves relative to the rod in the second direction and away from the photosensitive drum.

Images