Developing cartridge

Abstract

To provide a developing cartridge that enables arranging an elastic member, while forming a shaft and a cam integrally.SOLUTION: A developing cartridge 1 comprises: a casing 10 that can accommodate developer, and has a first outer surface in one end in a first direction; a developing roller 20 that is located in one end in a second direction of the casing 10; a shaft 61 that extends in the first direction; a first cam 62 that is located in one end in the first direction of the shaft 61; and an elastic member 35 that is located on an outer side in a radial direction of the shaft 61, and is located between the first outer surface and the first cam in the first direction. The first cam 62 has a first inclination plane 711 getting closer to the developing roller 20 in the second direction, as heading toward one end part from other end part of the shaft 61 in the first direction. Also, the first cam 62 is formed integrally with the shaft 61, and movable in the first direction together with the shaft 61. Therefor, a driving stroke can be shortened, comparing with a case where the shaft 61 and first cam 62 are separated members.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a developing cartridge.

Background Art

[0002] Conventionally, electrophotographic image forming apparatuses such as laser printers and LED printers are known. A developing cartridge is used in the image forming apparatus. The developing cartridge extends in a first direction and has a developing roller for supplying toner. For a conventional image forming apparatus, see, for example, Patent Document 1. The image forming apparatus of Patent Document 1 has a drawer unit. The drawer unit is attached to the image forming apparatus. The drawer unit also has a photosensitive drum. The developing cartridge is attached to the drawer unit. When the developing cartridge is attached to the drawer unit, the photosensitive drum and the developing roller come into contact with each other.

[0003] In the image forming apparatus of Patent Document 1, the state where the developing roller and the photosensitive drum are in contact and the state where the developing roller and the photosensitive drum are separated are switched. The developing cartridge further includes a shaft movable in the first direction, a cam located at one end of the shaft in the first direction, and an elastic member located between the shaft and the cam in the first direction. When the cam receives a pressing force in the first direction from the image forming apparatus, the shaft and the cam move in the first direction, and the developing cartridge can move between the contact state and the separated state.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] To ensure stable movement of the developing cartridge between contact and separation states, it is conceivable to form the shaft and cam as a single integrated unit. However, Patent Document 1 did not disclose the arrangement of the elastic member when the shaft and cam are formed as a single unit.

[0006] The object of this disclosure is to provide a developing cartridge that allows for the integral formation of a shaft and a cam while also allowing for the arrangement of an elastic member. [Means for solving the problem]

[0007] The first disclosure of the present application is a developing cartridge comprising: a housing capable of containing a developer, having a first outer surface located at one end of the housing in a first direction; a developing roller rotatable about a first axis extending in the first direction, having a developing roller located at one end of the housing in a second direction; a shaft along a second axis extending in the first direction, having a shaft movable in the first direction relative to the housing and the developing roller; a first cam located at one end of the shaft in the first direction and movable in the first direction together with the shaft, having a first inclined surface that approaches the developing roller in the second direction as it moves from the other end of the shaft in the first direction toward the one end, and being integrally formed with the shaft; and an elastic member expandable and contractible in the first direction, having an elastic member located radially outward of the shaft, and having an elastic member located between the first outer surface of the housing and the first cam in the first direction.

[0008] The second disclosure of the present application is a developing cartridge according to the first disclosure, characterized in that one side of the circumferential surface of the developing roller in the second direction is exposed to the outside of the housing, and the other side of the circumferential surface of the developing roller in the second direction is located on the inside of the housing.

[0009] A third disclosure of the present application is a developing cartridge according to the first or second disclosure, characterized in that the distance between the shaft and the first inclined surface in the second direction increases toward the radially outward direction of the shaft as the shaft moves from the other end toward the one end toward the first end toward the shaft.

[0010] A fourth disclosure of this application is a developing cartridge according to the first or second disclosure, characterized in that the elastic member is located between the first outer surface of the housing and the first cam in a state of natural length or compressed to a state of natural length.

[0011] The fifth disclosure of this application is a developing cartridge of the fourth disclosure, characterized in that the elastic member is located on the opposite side of the first inclined surface with respect to the shaft.

[0012] A sixth disclosure of the present application is a developing cartridge according to the first or second disclosure, wherein the developing cartridge comprises a gear cover located on the first outer surface of the housing, the gear cover covering at least a portion of the first outer surface of the housing, and at least a portion of the first cam is located in the first direction on the opposite side of the first outer surface of the housing from the gear cover.

[0013] The seventh disclosure of this application is a developing cartridge according to the sixth disclosure, characterized in that the housing has a groove extending in the first direction, and a portion of the shaft is located inside the groove.

[0014] The eighth disclosure of this application is a developing cartridge according to the seventh disclosure, wherein the gear cover has a hole into which the shaft is inserted.

[0015] The ninth disclosure of this application is a developing cartridge according to the sixth disclosure, wherein the gear cover has a first guide groove that guides the movement of the first cam in the first direction.

[0016] The tenth disclosure of the present application is a developing cartridge according to the ninth disclosure, wherein the first cam is movable in the first direction together with the shaft between a first position and a second position which is closer to the first outer surface of the housing than the first position in the first direction, and the guide groove has a first receiving surface facing the first cam in the radial direction of the shaft when the first cam is in the second position.

[0017] The eleventh disclosure of this application is a developing cartridge according to the first or second disclosure, comprising a second cam located at the other end of the shaft in the first direction and movable in the first direction together with the shaft and the first cam, the second cam having a second inclined surface that approaches the developing roller in the second direction as it moves from the other end of the shaft toward the one end, the second cam being integrally formed with the shaft and the first cam.

[0018] The twelfth disclosure of this application is a developing cartridge according to the first or second disclosure, characterized in that the shaft and the first cam are integrally formed from resin.

[0019] The thirteenth disclosure of this application is a developing cartridge according to the eleventh disclosure, characterized in that the shaft, the first cam and the second cam are integrally formed from resin.

[0020] A 14th disclosure of the present application is a developing cartridge according to the 11th disclosure, wherein the housing has a second outer surface located apart from the first outer surface in the first direction, and the developing cartridge further comprises a storage medium having an electrical contact surface, a holder for holding the electrical contact surface, the holder being located on the second outer surface of the housing and movable with respect to the housing together with the electrical contact surface, and a holder cover covering at least a portion of the holder, wherein the holder cover has a hole into which the shaft or the second cam is inserted in the first direction.

[0021] The 15th disclosure of the present application is the developing cartridge of the 14th disclosure, wherein the holder cover has a second guide groove for guiding the movement of the second cam in the first direction.

[0022] The 16th disclosure of the present application is the developing cartridge of the 15th disclosure, wherein the second cam is movable in the first direction together with the shaft and the first cam between a first position and a second position closer to the second outer surface of the housing than the first position in the first direction, and the second guide groove has a second receiving surface facing the second cam in the radial direction of the shaft when the second cam is in the second position.

Advantages of the Invention

[0023] According to the 1st to 16th disclosures of the present application, while the shaft and the cam are integrally formed, an elastic member can be arranged.

[0024] Further, according to the 8th disclosure of the present application, displacement of the position of the shaft can be suppressed.

[0025] Further, according to the 9th disclosure of the present application, displacement of the position of the first cam can be suppressed.

[0026] Further, according to the 10th disclosure of the present application, in the separated state where the first cam is in the second position, the first cam receives the load of the developing cartridge by contacting the first receiving surface. Thereby, the load applied to the shaft can be reduced, and deformation of the shaft can be suppressed.

[0027] Further, according to the 11th disclosure of the present application, by forming the second cam integrally with the shaft and the first cam, there is no need to consider the difference in linear expansion between the shaft, the first cam, and the second cam, and also, since the number of parts is reduced, the assembly error is reduced. Therefore, the driving stroke can be shortened compared to the case where the second cam is a separate member from the shaft and the first cam.

[0028] Furthermore, according to the 15th disclosure of this application, it is possible to suppress the displacement of the second cam.

[0029] Furthermore, according to the 16th disclosure of this application, when the second cam is in a separated state where it is in the second position, the second cam receives the load of the developing cartridge by contacting the second receiving surface. This reduces the load on the shaft and suppresses deformation of the shaft. [Brief explanation of the drawing]

[0030] [Figure 1] This is a conceptual diagram of an image forming apparatus. [Figure 2] This is a perspective view of a developing cartridge. [Figure 3] This is a perspective view of a developing cartridge. [Figure 4] This is a perspective view of a developing cartridge. [Figure 5] This is a perspective view of a disassembled developing cartridge. [Figure 6] This is a perspective view of the gear cover. [Figure 7] This is a cross-sectional view of the developing cartridge and drawer frame in contact. [Figure 8] This is a cross-sectional view of the developing cartridge and drawer frame in a separated state. [Figure 9] This is a perspective view of the developing cartridge and drawer frame in contact. [Figure 10] This is a perspective view of the developing cartridge and drawer frame in a separated state. [Modes for carrying out the invention]

[0031] Preferred embodiments of this disclosure will be described below with reference to the drawings.

[0032] In the following, the direction in which the developing roller extends will be referred to as the "first direction." The direction in which one end of the casing where the developing roller is located aligns with the other end of the casing will be referred to as the "second direction." The first and second directions intersect (preferably perpendicular to each other). The direction that intersects (preferably perpendicular to) the first and second directions will be referred to as the "third direction." The direction in which the first cam body extends will be referred to as the fourth direction. The fourth direction is perpendicular to the first direction and intersects with the second and third directions.

[0033] <1. Configuration of the image forming apparatus> Figure 1 is a conceptual diagram of an image forming apparatus 100. This image forming apparatus 100 is an electrophotographic printer. Examples of image forming apparatus 100 include laser printers and LED printers.

[0034] The image forming apparatus 100 comprises a plurality of developing cartridges 1, a drawer unit 90, and a main frame 101.

[0035] Multiple developing cartridges 1 can be mounted on a drawer unit 90. The drawer unit 90 is a drum cartridge on which the developing cartridges 1 are mounted. Multiple developing cartridges 1 can be mounted on the drawer unit 90. In this embodiment, the number of developing cartridges 1 is four. The drawer unit 90 has a frame 900. The frame 900 has multiple slots 91. In this embodiment, the number of multiple slots 91 is four. A developing cartridge 1 is mounted in each of the slots 91. The drawer unit 90 also has multiple photoreceptor drums 92. In this embodiment, the number of multiple photoreceptor drums 92 is four. The photoreceptor drums 92 are positioned for each of the four slots 91.

[0036] This drawer unit 90 has four slots 91 and four photosensitive drums 92. Therefore, in this image forming apparatus 100, four developing cartridges 1 are mounted in the drawer unit 90. The developing cartridges 1 are then mounted in the drawer unit 90 and installed inside the main frame 101.

[0037] The developing cartridge 1 has a developing roller 20 (see Figures 2 and 3) extending in a first direction. The photoreceptor drum 92 is rotatable about a rotation axis (drum axis) extending in a first direction. With the developing cartridge 1 installed in the slot 91 of the drawer unit 90, the surface of the developing roller 20 faces the surface of the photoreceptor drum 92. The drawer unit 90 is mounted on the main frame 101 (see Figure 1) with the developing cartridge 1 installed in the slot 91.

[0038] The four developing cartridges 1 each contain a developer (e.g., toner) of a different color (e.g., cyan, magenta, yellow, and black). However, multiple developing cartridges 1 may contain the same color developer. The number of developing cartridges 1 may be 1 to 3, or 5 or more.

[0039] The image forming apparatus 100 forms an image on printing paper using developer supplied from four developing cartridges 1.

[0040] <2. About the developing cartridge> Figures 2 to 4 are perspective views of the developing cartridge 1. Figure 5 is an exploded perspective view of the developing cartridge 1.

[0041] As shown in Figures 2 to 5, the developing cartridge 1 of this embodiment includes a casing 10, a developing roller 20, a gear cover 30, a coil spring 35, an IC chip assembly 40, a holder cover 50, and a separating member 60.

[0042] The casing 10 is a housing capable of containing a developer (e.g., toner) for electrophotographic printing. The casing 10 has a first outer surface 11 and a second outer surface 12. The first outer surface 11 and the second outer surface 12 are separated from each other in a first direction. The casing 10 extends in a first direction. The first outer surface 11 is located at one end of the casing 10 in the first direction. The second outer surface 12 is located at the other end of the casing 10 in the first direction. The gear cover 30 is located on the first outer surface 11. The IC chip assembly 40 and the holder cover 50 are located on the second outer surface 12.

[0043] The developing roller 20 is a roller that can rotate about a first axis X1 extending in a first direction. The developing roller 20 of this embodiment has a roller body 21 and a roller shaft 22. The roller body 21 is a cylindrical member extending in a first direction. For example, elastic rubber is used as the material for the roller body 21. The roller shaft 22 is a cylindrical member that penetrates the roller body 21 in a first direction. The material for the roller shaft 22 is metal or a conductive resin.

[0044] Note that the roller shaft 22 does not necessarily have to penetrate the roller body 21 in the first direction. For example, a pair of roller shafts 22 may extend from both ends of the roller body 21 in the first direction, respectively.

[0045] The casing 10 has an opening 15. The opening 15 connects the internal space of the casing 10 to the outside of the casing 10. The opening 15 is located at one end of the casing 10 in a second direction. The developing roller 20 is located at the opening 15. That is, the developing roller 20 is located at one end of the casing 10 in a second direction. One side of the circumferential surface of the developing roller 20 in the second direction is exposed to the outside of the casing 10. The other side of the circumferential surface of the developing roller 20 in the second direction is located inside the casing 10.

[0046] The roller body 21 is fixed to the roller shaft 22 in a way that prevents relative rotation. The developing gear (not shown) is also fixed to one end of the roller shaft 22 in a way that prevents relative rotation. Therefore, when the developing gear rotates, the roller shaft 22 rotates. Furthermore, the roller shaft 22 rotates together with the roller body 21.

[0047] When the developing cartridge 1 receives a driving force, the supply roller (not shown) supplies the developer from the casing 10 to the outer surface of the developing roller 20. At this time, the developer becomes triboelectrically charged between the supply roller and the developing roller 20. Meanwhile, a bias voltage is applied to the roller shaft 22 of the developing roller 20. As a result, the electrostatic force between the roller shaft 22 and the developer attracts the developer to the outer surface of the roller body 21.

[0048] Furthermore, the developing cartridge 1 has a layer thickness regulating blade (not shown). The layer thickness regulating blade makes the developer supplied to the outer surface of the roller body 21 a constant thickness. Subsequently, the developer on the outer surface of the roller body 21 is supplied to the photoreceptor drum 92 of the drawer unit 90. At this time, the developer moves from the roller body 21 to the photoreceptor drum 92 in accordance with the electrostatic latent image formed on the outer surface of the photoreceptor drum 92. As a result, the electrostatic latent image is made visible on the outer surface of the photoreceptor drum 92.

[0049] As shown in Figure 2, the gear cover 30 is located on the first outer surface 11 of the casing 10. The gear cover 30 covers a plurality of gears (not shown) that are rotatably mounted on the first outer surface 11 of the casing 10.

[0050] As shown in Figures 3 and 4, the IC chip assembly 40 and the holder cover 50 are located on the second outer surface 12 of the casing 10. As shown in Figure 4, the IC chip assembly 40 includes an IC chip 41 which is a storage medium and a holder 42 which holds the IC chip 41.

[0051] The holder 42 is located on the second outer surface 12 of the casing 10. The holder 42 is held by the holder cover 50. Various information about the developing cartridge 1 is recorded on the IC chip 41. The IC chip 41 has an electrical contact surface 411. The electrical contact surface 411 is made of a conductive metal. In this embodiment, the direction perpendicular to the first and second directions is referred to as the "third direction". The IC chip 41 is fixed to the outer surface of the holder 42 in the third direction.

[0052] The drawer unit 90 has an electrical connector. The electrical connector is, for example, made of metal. When the developing cartridge 1 is placed in the drawer unit 90, the electrical connector of the drawer unit 90 makes contact with the electrical contact surface 411. This allows the image forming apparatus to perform at least one of reading information from the IC chip 41 and writing information to the IC chip 41.

[0053] <3. Configuration of the gear cover, coil spring, holder cover, and separation member> Next, the detailed configurations of the gear cover 30, coil spring 35, holder cover 50, and separating member 60 will be described with reference to Figures 5 to 10. Figure 5 is an exploded perspective view of the developing cartridge 1. Note that only the casing 10, gear cover 30, IC chip assembly 40, holder cover 50, and separating member 60 are shown in Figure 5. Figure 6 is a perspective view of the gear cover 30. Figure 7 is a cross-sectional view of the developing cartridge 1 and drawer unit 90 in contact. Figure 8 is a cross-sectional view of the developing cartridge 1 and drawer unit 90 in separated state. Note that Figures 7 and 8 are cross-sectional views in a plane that passes through the second axis X2 and extends in the first direction and the fourth direction, which will be described later. Figure 9 is a perspective view of the developing cartridge 1 and drawer unit 90 in contact. Figure 10 is a perspective view of the developing cartridge 1 and drawer unit 90 in separated state. In Figures 9 and 10, only one developing cartridge 1 is shown, and the remaining three developing cartridges 1 are not shown. Furthermore, the developing roller 20 is not shown in Figures 9 and 10.

[0054] The separating member 60 is a member for switching the image forming apparatus 100 between a contact state and a separated state. Specifically, when the developing cartridge 1 is mounted on the drawer unit 90, the separating member 60 is a member for moving the casing 10 and developing roller 20 of the developing cartridge 1 between a contact position P1 and a separated position P2 relative to the drawer unit 90. When the developing cartridge 1 is mounted on the drawer unit 90, if the developing cartridge 1 is in the contact position P1, the developing roller 20 and the photosensitive drum of the drawer unit 90 are in contact. If the developing cartridge 1 is in the separated position P2, the developing roller 20 and the photosensitive drum of the drawer unit 90 are separated from each other.

[0055] When the developing cartridge 1 is mounted in the drawer unit 90, in its natural state, the separating member 60 is positioned at a first position Q1 relative to the casing 10. At this time, the image forming apparatus 100 is in contact with the casing 10. To move into a separated state, the image forming apparatus 100 applies a driving force from the main frame 101 to the separating member 60 of the developing cartridge 1. As a result, the separating member 60 moves in a first direction relative to the casing 10, and the separating member 60 is positioned at a second position Q2 relative to the casing 10. Consequently, the image forming apparatus 100 is in a separated state. In this embodiment, when moving from a contact state to a separated state, the developing cartridge 1 moves in a second direction, from one end of the casing 10 in the second direction to the other end of the casing 10 in the second direction. As a result, the developing roller 20 separates from the photoreceptor drum in the second direction, which is the separating direction.

[0056] As shown in Figure 5, the separating member 60 has a shaft 61, a first cam 62, and a second cam 63. The separating member 60 is integrally formed from resin. That is, the shaft 61, the first cam 62, and the second cam 63 are integrally formed from resin. Specifically, the separating member 60 is integrally molded by injection molding. The separating member 60 is movable in a first direction relative to the casing 10 between a first position Q1 shown in Figures 7 and 9 and a second position Q2 shown in Figures 8 and 10.

[0057] The shaft 61 is a columnar portion extending in the first direction. The shaft 61 is cylindrical. However, the shaft 61 may also be prismatic.

[0058] Furthermore, the shaft 61 is positioned along the outer surface of the casing 10. Specifically, the casing 10 has a third outer surface 16 and a fourth outer surface 17. The third outer surface 16 and the fourth outer surface 17 are separated from each other in a third direction that intersects (orthogonal in this embodiment) with the first and second directions. The third outer surface 16 is located at one end of the casing 10 in the third direction. The fourth outer surface 17 is located at the other end of the casing 10 in the third direction. The third outer surface 16 has a casing groove 18 that extends in the first direction. A portion of the shaft 61 is located inside the casing groove 18 of the casing 10.

[0059] The first cam 62 is located at one end of the shaft 61 in a first direction. The first cam 62, together with the shaft 61 and the second cam 63, is movable relative to the casing 10 in a first direction. The first cam 62 has a first cam body portion 71 and a first cam retaining portion 72.

[0060] The first cam body 71 extends in a fourth direction. That is, the first cam body 71 extends in a second direction and also extends in a third direction.

[0061] The first cam body 71 has a pressing force input surface 70 that receives pressing force from the image forming apparatus 100. The pressing force input surface 70 is located at one end of the first cam body 71 in the first direction. In the first direction, one end of the first cam body 71 is located on the opposite side from the second cam 63 to the other end of the first cam body 71 in the first direction. When moving the image forming apparatus 100 from a contact state to a separation state, the image forming apparatus 100 presses the pressing force input surface 70 in the first direction. The image forming apparatus 100 presses the pressing force input surface 70 in the first direction from one end of the casing 10 in the first direction to the other end of the casing 10 in the first direction. As a result, the separating member 60 moves from the first position Q1 to the second position Q2.

[0062] The first cam retaining portion 72 is located in the fourth direction, opposite to the first cam body portion 71 with respect to the shaft 61. That is, the first cam retaining portion 72 extends from the first cam body portion 71 in the fourth direction. In other words, the first cam retaining portion 72 extends from the first cam body portion 71 from one end of the casing 10 in the second direction to the other end of the casing 10 in the second direction. Also, the first cam retaining portion 72 extends from the first cam body portion 71 in the third direction, from the third outer surface 16 to the fourth outer surface 17.

[0063] The first cam retaining portion 72 has a through hole 721. The through hole 721 penetrates the first cam retaining portion 72 in a first direction. The through hole 720 is cylindrical.

[0064] The second cam 63 is located at the other end of the shaft 61 in the first direction. The second cam 63 is movable in the first direction together with the shaft 61 and the first cam 62. The second cam 63 has a second cam body portion 81 and a second cam retaining portion 82.

[0065] The second cam body portion 81 extends in the fourth direction. That is, the second cam body portion 81 extends in the second direction and also extends in the third direction. The direction in which the second body portion 81 extends is the same as the direction in which the first cam body portion 71 extends.

[0066] The second cam retaining portion 82 extends from the second cam body portion 81 in a first direction. The second cam retaining portion 82 extends from the second cam body portion 81 in the first direction from the first outer surface 11 to the second outer surface 12. The second cam retaining portion 82 is cylindrical.

[0067] As shown in Figure 6, the gear cover 30 has a cover portion 31, a hole 32, a columnar portion 33, and a first guide groove 34.

[0068] The cover portion 31 extends along the first outer surface 11. The cover portion 31 extends in the second and third directions. The cover portion 31 covers the first outer surface 11 and a plurality of gears (not shown) located on the first outer surface 11.

[0069] The hole 32 is a through-hole that penetrates the cover portion 31 in a first direction. The shaft 61 and the second cam 63 of the separating member 60 can be inserted into the hole 32. When the shaft 61 is inserted into the hole 32, the shaft 61 is held in place by the cover portion 31. In the assembly process of the developing cartridge 1, the shaft 61 is positioned inside the hole 32 by passing the second cam 63 through the hole 32.

[0070] The columnar portion 33 is a cylindrical part that extends from the cover portion 31 in a first direction. A coil spring 35 is attached to the outer circumference of the columnar portion 33. The columnar portion 33 is inserted into the through hole 720 of the first cam holding portion 72. Here, the diameter of the through hole 720 is smaller than the diameter of the coil spring 35. As a result, the coil spring 35 is held between the first outer surface 11 and the first cam holding portion 72 in the first direction.

[0071] The coil spring 35 is expandable and contractible in the first direction between a first length and a second length shorter than the first length. The coil spring 35 is an example of an elastic member. When the separating member 60 is in the first position Q1, the coil spring 35 is in the first length shown in Figure 7. When a pressing force is applied to the pressing force input surface 70 from the image forming apparatus 100, the separating member 60 moves from the first position Q1 to the second position Q2. As a result, the coil spring 35 contracts to the second length shown in Figure 8. When the pressing force applied to the pressing force input surface 70 from the image forming apparatus 100 is released, the coil spring 35 returns from the second length to the first length. As a result, the separating member 60 returns from the second position Q2 to the first position Q1. In this way, the separating member 60 moves in the first direction relative to the casing 10 due to the pressing force applied in the first direction and the elastic force of the coil spring 35.

[0072] The first guide groove 34 is a groove extending from the cover portion 31 in a first direction. The first guide groove 34 has a wall portion 36. The inner circumferential surface of the wall portion 36 is U-shaped when viewed in the first direction. The first cam holding portion 72 of the first cam 62 is inserted into the first guide groove 34. When the separating member 60 moves in the first direction, the first cam holding portion 72 moves in the first direction along the first guide groove 34. This prevents the position of the first cam 62 from shifting relative to the casing 10 when the separating member 60 moves between the first position Q1 and the second position Q2.

[0073] As shown in Figure 5, the holder cover 50 has a retaining hole 51 and a second guide groove 52.

[0074] The retaining hole 51 is a through-hole that penetrates the holder cover 50 in a first direction. The second cam retaining portion 82 of the second cam 63 is inserted into the retaining hole 51. This allows the holder cover 50 to hold the second cam 63.

[0075] The second guide groove 52 is a groove that extends in the first direction. The second cam body portion 81 of the second cam 63 is inserted into the second guide groove 52. When the separating member 60 moves in the first direction, the second cam body portion 81 moves in the first direction along the second guide groove 52. This prevents the position of the second cam 63 from shifting relative to the casing 10 when the separating member 60 moves between the first position Q1 and the second position Q2.

[0076] The first cam body portion 71 of the first cam 62 has a first inclined surface 711. As shown in Figure 3, in this embodiment, the first inclined surface 711 is located on a part of the circumferential surface of the shaft 61. The first inclined surface 711 is inclined with respect to the shaft 61 extending in a first direction. The first inclined surface 711 is a part of a conical surface centered on the second axis X2. As shown in Figures 3, 7, and 8, the first inclined surface 711 has a first inclined portion 711a and a second inclined portion 711b which has a smaller angle with respect to the shaft 61 than the first inclined portion 711a. The first inclined portion 711a is closer to the first outer surface 11 in the first direction than the second inclined portion 711b.

[0077] As a result, the first inclined surface 711 approaches the developing roller 20 in the second direction as it moves from the other end of the shaft 61 in the first direction toward one end of the shaft 61 in the first direction. That is, the first inclined surface 711 is inclined so that as it moves from the other end of the shaft 61 in the first direction toward one end of the shaft 61 in the first direction toward one end of the shaft 61 in the first direction toward one end of the casing 10 in the second.

[0078] Furthermore, as shown in Figures 7 and 8, the first cam holding portion 72 of the first cam 62 has a first contact surface 721. The first contact surface 721 is located in the fourth direction on the opposite side of the shaft 61 from the first cam body portion 71. The first contact surface 721 is perpendicular to the fourth direction. Also, the first contact surface 721 is perpendicular to the radial direction of the shaft 61.

[0079] The first guide groove 34 has a first receiving surface 360. In other words, the wall portion 36 has a first receiving surface 360. The first receiving surface 360 ​​is part of the wall portion 36 of the first guide groove 34. The first contact surface 721 faces the first receiving surface 360 ​​in the fourth direction. The surface of the wall portion 36 that faces the first contact surface 721 is referred to as the first receiving surface 360. The area where the first contact surface 721 and the first receiving surface 360 ​​face each other at the first position Q1 is smaller than the area where the first contact surface 721 and the first receiving surface 360 ​​face each other at the second position Q2.

[0080] The second cam body portion 81 of the second cam 63 has a second inclined surface 811. As shown in Figure 3, in this embodiment, the second inclined surface 811 is located on a part of the circumferential surface of the shaft 61. The second inclined surface 811 is inclined with respect to the shaft 61 extending in the first direction. The second inclined surface 811 is inclined with respect to the shaft 61 in the same way as the first inclined surface 711. As shown in Figures 3, 7, and 8, the second inclined surface 811 is part of a conical surface centered on the second axis X2. The second inclined surface 811 has a third inclined portion 811a and a fourth inclined portion 811b which has a smaller angle with respect to the shaft 61 than the third inclined portion 811a. The third inclined portion 811a is further from the second outer surface 12 in the first direction than the fourth inclined portion 811b.

[0081] As a result, the second inclined surface 811 approaches the developing roller 20 in the second direction as it moves from the other end of the shaft 61 in the first direction toward one end of the shaft 61 in the first direction. That is, the second inclined surface 811 is inclined so as to move from the other end of the casing 10 in the second direction toward one end of the casing 10 in the second direction toward the other end of the shaft 61 in the first direction toward one end of the shaft 61 in the first direction.

[0082] Furthermore, as shown in Figures 7 and 8, the second cam body 81 of the second cam 63 has a second contact surface 812. The second contact surface 812 is located in the fourth direction, opposite to the second inclined surface 811 with respect to the shaft 61. The second contact surface 812 is perpendicular to the fourth direction. Also, the second contact surface 812 is perpendicular to the radial direction of the shaft 61.

[0083] The second guide groove 52 has a second receiving surface 520. In other words, the second receiving surface 520 is part of the second guide groove 52. The second contact surface 812 faces the second receiving surface 520 in the fourth direction. The area where the second contact surface 812 and the second receiving surface 520 face each other at the first position Q1 is smaller than the area where the second contact surface 812 and the second receiving surface 520 face each other at the second position Q2.

[0084] The first cam 62 and the second cam 63 are movable in a first direction together with the shaft 61. When the separating member 60 moves in the first direction from the first position Q1 shown in Figures 7 and 9 to the second position Q2 shown in Figures 8 and 10, the first cam 62 approaches the first outer surface 11 of the casing 10 and the cover portion 31 of the gear cover 30, and the second cam 63 moves away from the first outer surface 11. <4. Regarding the separation operation by the separation member 60> Next, we will explain the movement of the image forming apparatus 100 when switching between the contact state and the separated state.

[0085] As shown in Figures 9 and 10, the frame 900 of the drawer unit 90 has four slots 91. As shown in Figures 8 to 10, the frame 900 of the drawer unit 90 has a first side frame 901 and a second side frame 902. The first side frame 901 and the second side frame 902 are located apart in a first direction. The photoreceptor drum 92 is located between the first side frame 901 and the second side frame in a first direction. When the developing cartridge 1 is installed in the slot 91 of the drawer unit 90, the developing cartridge 1 is located between the first side frame 901 and the second side frame 902 in a first direction. Also, in a first direction, the first outer surface 11 of the developing cartridge 1 faces the first side frame 901. Furthermore, when the developing cartridge 1 is installed in the slot 91 of the drawer unit 90, in a first direction, the second outer surface 12 of the developing cartridge 1 faces the second side frame 902.

[0086] The first side frame 901 has four first cam receiving surfaces 93. The second side frame 902 has four second cam receiving surfaces 94. When the developing cartridge 1 is installed in the slot 91, the first cam receiving surfaces 93 face the first inclined surface 711 of the first cam 62 of the developing cartridge 1 in the first and fourth directions. Also when the developing cartridge 1 is installed in the slot 91, the second cam receiving surfaces 94 face the second inclined surface 811 of the second cam 63 of the developing cartridge 1 in the first and fourth directions.

[0087] When the image forming apparatus 100 is moved from a contact state to a separated state, a pressing force in a first direction is input from the image forming apparatus 100 to the pressing force input surface 70 of the first cam 62. In other words, when the image forming apparatus 100 is moved from a contact state to a separated state, a pressing force is input from the image forming apparatus 100 to the pressing force input surface 70 of the first cam 62, moving from one end of the casing 10 in a first direction to the other end of the casing 10 in a first direction. As a result, the separating member 60 moves from a first position Q1 to a second position Q2. Consequently, the first inclined surface 711 of the first cam 62 comes into contact with the first cam receiving surface 93 of the frame 900 of the drawer unit 90, and the second inclined surface 811 of the second cam 63 comes into contact with the second cam receiving surface 94 of the frame 900. As a result, the separating member 60 rides up onto the first cam receiving surface 93 and the second cam receiving surface 94 of the frame 900, causing the developing roller 20 to move away from the photoreceptor drum 92 in the second direction. In this way, the casing 10 of the developing cartridge 1 moves in the second direction from a contact position P1 where the developing roller 20 and the photoreceptor drum 92 are in contact to a separating position P2 where the developing roller 20 and the photoreceptor drum 92 are separated.

[0088] At this time, the first inclined surface 711 of the first cam 62 comes into contact with the first cam receiving surface 93. Then, the first inclined surface 711 of the first cam 62 moves in the first direction. As described above, in the first direction, the first inclined surface 711 extends radially outward from the shaft 61 as it moves from the second cam 63 toward the first cam 62. Therefore, when the first cam 62 moves in the first direction, the position of the first inclined surface 711 that contacts the first cam receiving surface 93 moves away from the shaft 61 in the radial direction. The first inclined surface 711 and the first cam receiving surface 93 face each other in the second direction. In other words, when the first inclined surface 711 moves in the first direction, it also moves away from the first cam receiving surface 93 in the second direction.

[0089] Similarly, the second inclined surface 811 of the second cam 63 contacts the second cam receiving surface 94. Then, the second inclined surface 811 of the second cam 63 moves in the first direction. As described above, in the first direction, the second inclined surface 811 extends radially outward from the shaft 61 as it moves from the second cam 63 toward the first cam 62. Therefore, as the second cam 63 moves in the first direction, the position of the second inclined surface 811 that contacts the second cam receiving surface 94 moves away from the shaft 61 in the radial direction. The second inclined surface 811 and the second cam receiving surface 94 face each other in the second direction. In other words, as the second inclined surface 811 moves in the first direction, it also moves away from the second cam receiving surface 94 in the second direction.

[0090] The first cam 62 and the second cam 63 move in the first direction while simultaneously moving in the second direction. As a result, the separating member 60 moves in the first direction while simultaneously moving in the second direction. When the separating member 60 moves in the second direction, the casing 10 and the developing roller 20 also move in the second direction. As a result, the developing roller 20 is positioned at a separated position P2 away from the photoreceptor drum 92 in the second direction. In other words, the image forming apparatus 100 enters a separated state.

[0091] When the image forming apparatus 100 is in a separated state, the separating member 60 supports the load of the developing cartridge 1. At this time, the first contact surface 721 of the first cam 62 contacts the first receiving surface 360 ​​of the first guide groove 34 of the gear cover 30, and the second contact surface 812 of the second cam 63 contacts the second receiving surface 520 of the holder cover 50. As a result, the first cam 62 and the second cam 63 support the developing cartridge 1 via the gear cover 30 and the holder cover 50. In this way, when the image forming apparatus 1 is separated, the load on the shaft 61 can be reduced by the first cam 62 and the second cam 63 supporting the developing cartridge 1. Therefore, deformation of the shaft 61 can be suppressed.

[0092] When the image forming apparatus 100 is moved from a separated state to a contact state, the image forming apparatus 100 releases the pressing force from the image forming apparatus 100 onto the driving force input surface 70 of the first cam 62. When the pressing force from the first cam 62 onto the pressing force input surface 70 is released, the length of the coil spring 35 extends from the second length to the first length. As a result, the separating member 60 moves from the second position Q2 to the first position Q1.

[0093] As the separating member 60 moves from the second position Q2 to the first position Q1, the first inclined surface 711 of the first cam 62 moves in the second direction toward the first cam receiving surface 93. Also, the second inclined surface 811 of the second cam 63 moves in the second direction toward the second cam receiving surface 94. Consequently, the casing 10 and the developing roller 20 move in the second direction. Therefore, the developing roller 20 moves toward the photoreceptor drum 92 in the second direction. The surface of the developing roller 20 then comes into contact with the surface of the photoreceptor drum 92. That is, the casing 10 and the developing roller 20 of the developing cartridge 1 are located at the contact position P1. In other words, the image forming apparatus 100 is in contact.

[0094] In the separated state, in order to separate the developing roller 20 and the photoreceptor drum 92, it is necessary to move the first cam 62 and the second cam 63 from the first position Q1 to the second position Q2. If the shaft 61, the first cam 62 and the second cam 63 are each made of separate parts, manufacturing errors for each part and dimensional errors due to the assembly of the parts will occur. Also, for example, if the shaft 61 is made of metal and the first cam 62 is made of resin, the coefficient of thermal expansion of the shaft 61 and the first cam 62 will be different, so it will be necessary to overestimate the dimensional errors of the shaft 61 and the first cam 62.

[0095] In this separating member 60, the dimensional error between the shaft 61 and the first cam 62 can be reduced by integrally forming the shaft 61 and the first cam 62. Furthermore, in this separating member 60, the dimensional error between the shaft 61, the first cam 62 and the second cam 63 can also be reduced by integrally forming the shaft 61, the first cam 62 and the second cam 63. As a result, the stroke required to move the separating member 60 from the first position Q1 to the second position Q2 can be shortened.

[0096] <5. Variation> While embodiments of the present disclosure have been described above, the present disclosure is not limited to the embodiments described above.

[0097] In the above embodiment, the separating member 60 was integrally formed with a shaft 61, a first cam 62, and a second cam 63. However, the shaft 61 and the first cam 62 may be integrally formed, and the second cam 63 may not be included. In other words, the second cam 63 may be a separate member from the member in which the shaft 61 and the second cam 62 are integrally formed.

[0098] In the above embodiment, the separating member 60 has a first cam 62 and a second cam 63. However, the separating member 60 only needs to have at least one of the first cam 62 and the second cam 63. Also, the separating member 60 only needs to have at least one of the first inclined surface 711 and the second inclined surface 811.

[0099] In the above embodiment, the retaining hole 51 of the second cam retaining portion 82 was a through hole. However, the retaining hole 51 may be a recess instead of a through hole. The retaining hole 51 may also be located on the first cam 62 side in the first direction relative to the second cam 63. In that case, the shaft 61 is located inside the retaining hole 51, and the holder cover 50 holds the shaft 61.

[0100] In the above embodiment, the first inclined surface 711 of the first cam 62 was part of a conical surface. However, the first inclined surface 711 may be part of a polygonal pyramidal surface. Furthermore, although the first inclined surface 711 is a gently sloping surface, irregularities such as steps may be provided along the slope. Moreover, the first inclined surface 711 may be curved.

[0101] In the above embodiment, the second inclined surface 811 of the second cam 63 was part of a conical surface. However, the second inclined surface 811 may also be part of a polygonal pyramidal surface. Furthermore, although the second inclined surface 811 is a gently sloping surface, irregularities such as steps may be provided along the slope. Moreover, the second inclined surface 811 may be curved.

[0102] In the above embodiment, a coil spring 35 was given as an example of an elastic member, but it is not limited to this. The elastic member can be any member that has elastic force, such as a leaf spring, torsion spring, rubber, or sponge.

[0103] Furthermore, the elements that appear in the above embodiments and modifications may be combined as appropriate, to the extent that no contradictions arise. [Explanation of symbols]

[0104] 1. Developing cartridge 10 Casing 11 First outer surface 12 Second outer surface 18 casing grooves 20 Developing roller 30 Gear Cover 31 Cover section 32 holes 33 Columnar part 34. First guide groove 35 Coil springs 41 IC chips 42 holder 50 Holder Cover 51 Retaining hole 52 Second guide groove 60 Separating member 61 Shaft 62 First Cam 63 Second Cam 70 Driving force input surface 90 drawer unit 91 slots 93 First cam receiving surface 94 Second cam receiving surface 100 Image forming apparatus 360 First receiving surface 411 Electrical contact surface 520 Second receiving surface 711 1st slope 720 Through hole 721 1st contact surface 811 2nd slope 812 Second contact surface Q1 1st position Q2 2nd position X1 1st axis X2 2nd axis

Claims

1. A housing capable of containing a developer, the housing having a first outer surface located at one end of the housing in a first direction, A developing roller rotatable about a first axis extending in the first direction, the developing roller located at one end of the housing in the second direction, A shaft extending in the first direction along a second axis, the shaft being movable in the first direction relative to the housing and the developing roller, A first cam located at one end of the shaft in the first direction and movable together with the shaft in the first direction, having a first inclined surface that approaches the developing roller in the second direction as it moves from the other end of the shaft toward the one end in the first direction, and a first cam formed integrally with the shaft, A developing cartridge characterized by comprising: an elastic member that is expandable and contractible in the first direction, located radially outside the shaft and not enclosing the entire circumferential area of ​​the shaft, and located between the first outer surface of the housing and the first cam in the first direction.

2. A developing cartridge according to claim 1, One side of the circumferential surface of the developing roller in the second direction is exposed to the outside of the housing, A developing cartridge characterized in that the other side of the circumferential surface of the developing roller in the second direction is located inside the housing.

3. A developing cartridge according to claim 1 or claim 2, The distance between the shaft and the first inclined surface in the second direction is A developing cartridge characterized in that, as the shaft moves from the other end toward the one end in the first direction, the distance between the shaft and the first inclined surface increases toward the radially outward direction of the shaft.

4. A developing cartridge according to claim 1 or claim 2, The developing cartridge is characterized in that the elastic member is positioned between the first outer surface of the housing and the first cam in a state of natural length or compressed to a state of natural length.

5. A developing cartridge according to claim 4, The developing cartridge is characterized in that the elastic member is located on the opposite side of the first inclined surface with respect to the shaft.

6. A developing cartridge according to claim 1 or claim 2, The aforementioned developing cartridge is A gear cover located on the first outer surface of the housing, comprising a gear cover that covers at least a portion of the first outer surface of the housing, At least a portion of the first cam is A developing cartridge characterized in that, in the first direction, it is located on the opposite side of the first outer surface of the housing relative to the gear cover.

7. A developing cartridge according to claim 6, The housing has a groove extending in the first direction, A developing cartridge characterized in that a portion of the shaft is located inside the groove.

8. A developing cartridge according to claim 7, The developing cartridge is characterized in that the gear cover has a hole into which the shaft is inserted.

9. A developing cartridge according to claim 6, The gear cover is A developing cartridge characterized by having a first guide groove that guides the movement of the first cam in the first direction.

10. A developing cartridge according to claim 9, The first cam is The shaft is movable in the first direction between a first position and a second position which is closer to the first outer surface of the housing than the first position in the first direction. The first guide groove is A developing cartridge characterized in that, when the first cam is in the second position, it has a first receiving surface facing the first cam in the radial direction of the shaft.

11. A developing cartridge according to claim 1 or claim 2, A second cam located at the other end of the shaft in the first direction and movable in the first direction together with the shaft and the first cam, the second cam having a second inclined surface that approaches the developing roller in the second direction as it moves from the other end of the shaft toward the one end, A developing cartridge characterized in that the second cam is formed integrally with the shaft and the first cam.

12. A developing cartridge according to claim 1 or claim 2, A developing cartridge characterized in that the shaft and the first cam are integrally formed from resin.

13. A developing cartridge according to claim 11, A developing cartridge characterized in that the shaft, the first cam, and the second cam are integrally formed from resin.

14. A developing cartridge according to claim 11, The aforementioned enclosure is In the first direction, it has a second outer surface located away from the first outer surface, The aforementioned developing cartridge is A storage medium having an electrical contact surface, A holder for holding the electrical contact surface, the holder being located on the second outer surface of the housing, and the holder being movable together with the electrical contact surface with respect to the housing, The holder further comprises a holder cover that covers at least a portion of the holder, The holder cover is, A developing cartridge characterized by having a hole into which the shaft or the second cam is inserted in the first direction.

15. A developing cartridge according to claim 14, The holder cover is, A developing cartridge characterized by having a second guide groove that guides the movement of the second cam in the first direction.

16. A developing cartridge according to claim 15, The second cam is, The shaft and the first cam are movable in the first direction between a first position and a second position which is closer to the second outer surface of the housing than the first position in the first direction. The second guide groove is A developing cartridge characterized in that, when the second cam is in the second position, the shaft has a second receiving surface that faces the second cam in the radial direction.

Images