Developing cartridge

Abstract

To provide a developing cartridge with which it is possible to suppress a shaft from moving in an axial direction.SOLUTION: A developing cartridge 1 comprises a housing 10, a separation shaft 50, and a first protective cover 80. The separation shaft 50 is capable of moving to the housing 10 in the axial direction between a first position and a second position. The separation shaft 50 extends in the axial direction. The first protective cover 80 covers a part of the separation shaft 50 while the separation shaft 50 is located at the second position. The first protective cover 80 has a claw 84. While the separation shaft 50 is located at the second position, the claw 84 engages with the separation shaft 50 and holds the separation shaft 50 at the second position so that the separation shaft 50 does not move from the second position to the first position. Thus, the separation shaft 50 can be restrained from moving in the axial direction.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present disclosure relates to a developer cartridge. [Background technology]

[0002] 2. Description of the Related Art Conventionally, electrophotographic image forming apparatuses such as laser printers, LED printers, etc. are known. A conventional image forming apparatus is described in, for example, Patent Document 1.

[0003] The image forming apparatus of Patent Document 1 has a drum unit (drawer) and a developing cartridge. The developing cartridge is mountable to the drum unit. The developing cartridge has a developing roller. The drum unit has a photosensitive drum. When the developing cartridge is mounted to the drum unit, the developing roller comes into contact with the photosensitive drum. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2023-024753 A Summary of the Invention [Problem to be solved by the invention]

[0005] The developer cartridge of Patent Document 1 has a shaft. When the image forming device presses the shaft in the axial direction while the developer cartridge is attached to the drum unit, the shaft moves in the axial direction relative to the housing of the developer cartridge. Then, the shaft comes into contact with the frame of the drum unit, causing the developer cartridge to move in the separation direction relative to the drum unit. As a result, the developer roller can be separated from the photosensitive drum.

[0006] However, when the developing cartridge is transported, it is desirable to be able to prevent the shaft from moving in the axial direction.

[0007] An object of the present disclosure is to provide a developing cartridge capable of suppressing axial movement of the shaft. [Means for solving the problem]

[0008] The first disclosure is characterized by comprising a housing capable of containing toner, a developing roller rotatable about a developing axis extending in an axial direction, a shaft movable in the axial direction relative to the housing between a first position and a second position, the shaft extending in the axial direction, and a protective cover covering a portion of the shaft when the shaft is positioned at the second position, the protective cover having a claw that engages with the shaft and holds the shaft at the second position so that the shaft does not move from the second position to the first position when the shaft is positioned at the second position.

[0009] A second disclosure is the developing cartridge of the first disclosure, characterized in that the protective cover is detachable from the housing.

[0010] A third disclosure is the developing cartridge of the second disclosure, further comprising a memory located at one end of the housing in the axial direction, and the protective cover covers the memory when attached to the housing.

[0011] A fourth disclosure is a developing cartridge according to any one of the first to third disclosures, characterized in that the protective cover further includes an arm extending in the axial direction toward the shaft, and the claw protrudes from the arm in a direction intersecting the axial direction.

[0012] The fifth disclosure is a developing cartridge as disclosed in the fourth disclosure, characterized in that the shaft has a cam located at one end in the axial direction, and when the shaft is positioned at the second position, the claw engages with the cam.

[0013] A sixth disclosure is the developing cartridge of the fifth disclosure, further comprising a spring that urges the shaft from the second position toward the first position, and when the shaft is positioned at the second position, the claw and the cam are in contact in the axial direction.

[0014] The seventh disclosure is the developing cartridge of the fifth disclosure, characterized in that the cam has an inclined surface inclined with respect to the axial direction, and the inclined surface contacts the claw when the shaft moves from the first position to the second position.

[0015] The eighth disclosure is the developing cartridge of the fifth disclosure, characterized in that the shaft further has a protruding shaft protruding from the cam toward one end of the shaft in the axial direction, and the protective cover further has a cylindrical portion into which the protruding shaft is inserted when the shaft is positioned at the second position.

[0016] A ninth disclosure is a developing cartridge as disclosed in the third disclosure, further comprising a side cover covering the other end of the housing in the axial direction, and when the shaft is positioned in the second position, the other end of the shaft in the axial direction is located closer to the housing than the end of the side cover that is farthest from the housing in the axial direction.

[0017] A tenth disclosure is a developing cartridge according to any one of the second to ninth disclosures, characterized in that when the shaft is positioned at the first position, the protective cover can be attached to the housing.

[0018] An eleventh disclosure is a developing cartridge according to any one of the first to tenth disclosures, which is mountable to a drum unit having a photosensitive drum, and is characterized in that when the developing cartridge is mounted to the drum unit and the shaft moves from the first position toward the second position, the developing roller moves from a contact position in contact with the photosensitive drum to a separated position away from the photosensitive drum.

[0019] A twelfth disclosure is a developing cartridge according to any one of the first to eleventh disclosures, characterized in that when the shaft is positioned in the first position, the claw and the shaft are spaced apart. Effect of the Invention

[0020] According to the first to twelfth disclosures, the shaft can be held in the second position by the claws of the protective cover, thereby making it possible to prevent the shaft from moving in the axial direction. [Brief description of the drawings]

[0021] [Figure 1] FIG. 1 is a schematic diagram of an image forming apparatus. [Diagram 2] FIG. [Diagram 3] 2 is a cross-sectional view of the developing cartridge taken along a line perpendicular to a first direction. [Figure 4] FIG. 2 is a cross-sectional view of the drum unit with the developing cartridge attached, including the spacing shaft (the spacing shaft is in a first position). [Diagram 5] 4 is a cross-sectional view of the drum unit with the developing cartridge attached, including the spacing shaft (the spacing shaft is in a second position). FIG. [Figure 6] FIG. 2 is a perspective view of the developing cartridge with the first protective cover and the second protective cover attached (the separating shaft is in the first position). [Figure 7] FIG. 2 is a perspective view of the developing cartridge 1 in the vicinity of the first protective cover (the separation shaft is in the first position). [Figure 8]FIG. 13 is a perspective view of the developing cartridge with the first protective cover and the second protective cover attached (the separating shaft is in the second position). [Figure 9] FIG. 2 is a perspective view of the developing cartridge 1 in the vicinity of the first protective cover (the separation shaft is in the second position). [Figure 10] 4 is a cross-sectional view perpendicular to the first direction of the developing cartridge with the second protective cover attached. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0023] In the following description, the axial direction in which the development shaft of the development roller 20 extends is referred to as the "first direction." Also, the direction in which one end of the housing 10 of the development cartridge 1 where the development roller 20 is located is aligned with the other end of the housing 10 is referred to as the "second direction." The first direction and the second direction intersect with each other. For example, the first direction and the second direction are perpendicular to each other.

[0024] <1. Configuration of image forming device> FIG 1 is a schematic diagram of an image forming apparatus 100. The image forming apparatus 100 is an electrophotographic printer. Specifically, the image forming apparatus 100 is a laser printer or an LED printer. As shown in FIG 1, the image forming apparatus 100 includes a main body frame 101, a drum unit 2, and four developing cartridges 1.

[0025] The four developing cartridges 1 can be attached to the drum unit 2. Furthermore, the drum unit 2 to which the four developing cartridges 1 are attached can be attached to a main body frame 101.

[0026] The four developer cartridges 1 contain toner of different colors. For example, a developer cartridge 1 containing yellow toner, a developer cartridge 1 containing magenta toner, a developer cartridge 1 containing cyan toner, and a developer cartridge 1 containing black toner can be attached to the drum unit 2. The image forming device 100 prints an image on the surface of a printing paper using toner supplied from the developer cartridges 1.

[0027] <2. Structure of the developing cartridge> Fig. 2 is a perspective view of the developing cartridge 1. Fig. 3 is a cross-sectional view perpendicular to the first direction of the developing cartridge 1. As shown in Figs. 2 and 3, the developing cartridge 1 includes a housing 10, a developing roller 20, a gear portion 30, a memory assembly 40, and a spacer shaft 50.

[0028] <2-1. Cabinet> The housing 10 is a container capable of storing toner. 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.

[0029] A storage chamber 13 is provided inside the housing 10. The toner is stored in the storage chamber 13. The housing 10 also 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 storage chamber 13 communicate with each other via the opening 14. As shown in FIG. 3, the developing cartridge 1 also has a handle 161 at the other end of the housing 10 in the second direction.

[0030] <2-2. Developing roller> The developing roller 20 is a roller that can rotate about a development axis that extends in the first direction. The developing roller 20 is located in the opening 14 of the housing 10. That is, the developing roller 20 is located at one end of the housing 10 in the second direction. As shown in FIG. 1, the drum unit 2 has a photosensitive drum 70. When the developing cartridge 1 is attached to the drum unit 2, the developing roller 20 comes into contact with the photosensitive drum 70.

[0031] As shown in FIG. 3, the developing roller 20 has a developing roller body 21 and a developing roller shaft 22. The developing roller body 21 is a cylindrical member extending in a first direction. The developing roller body 21 is made of, for example, elastic rubber. The developing roller shaft 22 is a columnar member penetrating the developing roller body 21 and extending in the first direction. The developing roller body 21 is fixed to the developing roller shaft 22. The developing roller shaft 22 is made of metal or conductive resin.

[0032] The developing roller 20 is supported by the housing 10 in a state in which it can rotate about a development axis extending in a first direction. The developing roller 20 rotates about the development axis by a driving force supplied from the image forming apparatus 100. The toner in the housing 10 is carried on the outer surface of the developing roller 20.

[0033] As shown in FIG. 3, the developing cartridge 1 has a blade 23. The blade 23 is located in the opening 14. One end of the blade 23 is fixed to the housing 10. The other end of the blade 23 contacts the outer circumferential surface of the developing roller 20. More specifically, the other end of the blade 23 contacts the toner carried on the outer circumferential surface of the developing roller 20. The blade 23 extends in a first direction along the outer circumferential surface of the developing roller 20. The blade 23 shapes the toner carried on the outer circumferential surface of the developing roller 20 to a predetermined thickness.

[0034] <2-3. Gear section> The gear unit 30 is located on the second outer surface 12 of the housing 10. The gear unit 30 has a side cover 31, a coupling 32, and a plurality of gears. The side cover 31 is attached to the second outer surface 12 of the housing 10. Specifically, the side cover 31 is fixed to the second outer surface 12 of the housing 10 by screws. The side cover 31 covers the second outer surface 12 of the housing 10.

[0035] The coupling 32 and the multiple gears are each rotatable about an axis extending in the first direction. At least some of the multiple gears are located between the second outer surface 12 of the housing 10 and the side cover 31 in the first direction. That is, at least some of the multiple gears are covered by the side cover 31.

[0036] The coupling 32 is exposed from the side cover 31. When the drum unit 2 in which the developing cartridge 1 is mounted is mounted in the image forming apparatus 100, the drive shaft of the image forming apparatus 100 is connected to the coupling 32. Then, the rotation of the drive shaft is transmitted to the developing roller 20 via the coupling 32 and multiple gears.

[0037] <2-4.Memory Assembly> The memory assembly 40 is located on the first outer surface 11 of the housing 10. As shown in FIG.

[0038] The memory 41 is a storage medium that stores information about the developing cartridge 1. The memory 41 is, for example, an IC chip. For example, information about the specifications or lifespan of the developing cartridge 1 is stored in the memory 41. The memory 41 has an electrical contact surface 411. The electrical contact surface 411 is electrically connected to a memory element of the memory 41. The electrical contact surface 411 is located on the outer surface of the holder 42. In this embodiment, the memory 41 is attached to the outer surface of the holder 42. However, only the electrical contact surface 411 of the memory 41 may be attached to the holder 42, and the memory element of the memory 41 may be attached to another part of the developing cartridge 1.

[0039] The holder cover 43 is attached to the first outer surface 11 of the housing 10. At least a portion of the holder 42 is covered by the holder cover 43. The holder 42 is located between the first outer surface 11 of the housing 10 and the holder cover 43. The holder 42 is movable relative to the housing 10 and the holder cover 43. Therefore, the electrical contact surface 411 of the memory 41 is also movable relative to the housing 10 and the holder cover 43.

[0040] <2-5. Spaced shaft> When the drum unit 2 with the four developer cartridges 1 mounted therein is mounted in the image forming apparatus 100, the image forming apparatus 100 can cause each developer cartridge 1 to perform a separation operation. The separation operation is an operation for moving the developer roller 20 from a contact position where it contacts the photosensitive drum 70 to a separation position where it is separated from the photosensitive drum 70. The image forming apparatus 100 performs the separation operation on the developer cartridge 1 that is not being used among the four developer cartridges 1. As a result, the developer roller 20 of the developer cartridge 1 that is not being used is separated from the photosensitive drum 70.

[0041] The spacing shaft 50 is an example of a "shaft." The spacing shaft 50 is a component for switching the developing roller 20 between the contact position and the separated position described above. In other words, the developing cartridge 1 switches from a state in which the developing roller 20 is in the contact position to a state in which the developing roller 20 is in the separated position by the spacing shaft 50. The spacing shaft 50 is located between one end and the other end of the housing 10 in the second direction. In addition, the spacing shaft 50 extends in the first direction.

[0042] As shown in Fig. 2, the spaced shaft 50 has a first cam 51, a second cam 52, and a shaft body 53. The spaced shaft 50 is made of, for example, resin. Specifically, the first cam 51, the second cam 52, and the shaft body 53 are integrally molded from resin. However, the first cam 51, the second cam 52, and the shaft body 53 may be separate parts. In that case, only the first cam 51 and the second cam 52 may be made of resin, and the shaft body 53 may be made of metal.

[0043] As shown in FIG. 2, the developing cartridge 1 has a first hole 191, a second hole 192, and a guide groove 193. The first hole 191 is located at one end of the developing cartridge 1 in the first direction. The first hole 191 is a hole extending in the first direction. The second hole 192 is located at the other end of the developing cartridge 1 in the first direction. The second hole 192 is a hole extending in the first direction. The guide groove 193 is located between the first hole 191 and the second hole 192 in the first direction. The guide groove 193 extends in the first direction on the outer surface of the housing 10.

[0044] The shaft body 53 is disposed in the guide groove 193. The shaft body 53 extends in a first direction along the guide groove 193. One end of the spaced shaft 50 in the first direction is inserted into the first hole 191. As a result, one end of the spaced shaft 50 in the first direction is supported by the housing 10. The other end of the spaced shaft 50 in the first direction is inserted into the second hole 192. As a result, the other end of the spaced shaft 50 in the first direction is supported by the housing 10.

[0045] The first cam 51 is an example of a "cam." The first cam 51 is located at one end of the spacer shaft 50 in the first direction. The first cam 51 is located on the first outer surface 11 of the housing 10. The first cam 51 has a first inclined surface 511. The first inclined surface 511 is an example of an "inclined surface." The first inclined surface 511 is a part of a circumferential surface centered on the shaft main body 53. The first inclined surface 511 is inclined with respect to the first direction. More specifically, the first inclined surface 511 is inclined so as to approach the developing roller 20 in the second direction as it approaches the other end of the spacer shaft 50 in the first direction.

[0046] The second cam 52 is located at the other end of the spacer shaft 50 in the first direction. The second cam 52 is located on the second outer surface 12 of the housing 10. The second cam 52 has a second inclined surface 521. The second inclined surface 521 is a part of a circumferential surface centered on the shaft main body 53. The second inclined surface 521 is inclined with respect to the first direction. More specifically, the second inclined surface 521 is inclined so as to approach the developing roller 20 in the second direction as it approaches the other end of the spacer shaft 50 in the first direction.

[0047] Furthermore, the spaced shaft 50 has a protruding shaft 54. The protruding shaft 54 ​​protrudes from the first cam 51 toward one end of the spaced shaft 50 in the first direction. That is, the protruding shaft 54 ​​protrudes from the first cam 51 toward the opposite side to the second cam 52 in the first direction.

[0048] The spacing shaft 50 is movable in the first direction between a first position and a second position relative to the housing 10 and the developing roller 20. The second position is a position closer to one end of the spacing shaft 50 than the first position. Therefore, the movement from the first position to the second position is a movement in a direction from the second cam 52 toward the first cam 51.

[0049] The developing cartridge 1 also has a spring 55 (see FIGS. 4 and 5) that biases the spacing shaft 50. The spring 55 is an elastic member that is expandable and contractible in a first direction. For example, a coil spring is used for the spring 55. The spring 55 is disposed between the second outer surface 12 of the housing 10 and the second cam 52 in a state in which it is contracted in the first direction from its natural length. Therefore, the elastic force of the spring 55 biases the spacing shaft 50 from the second position toward the first position. Therefore, the spacing shaft 50 is disposed in the first position when it is not subjected to an external force.

[0050] <3. About the separation operation> Next, the separating operation of the image forming apparatus 100 will be described. Figures 4 and 5 are cross-sectional views including the separating shaft 50 of the drum unit 2 in which the developing cartridge 1 is mounted. Figure 4 shows a state in which the separating operation is not being performed. Figure 5 shows a state in which the separating operation is being performed.

[0051] 4 and 5, the image forming apparatus 100 has a pressing shaft 102. When the drum unit 2, to which the four developing cartridges 1 are attached, is attached to the main body frame 101, the pressing shaft 102 faces the second cams 52 of the developing cartridges 1 in the first direction.

[0052] The pressing shaft 102 is movable in the first direction between a retracted position and a protruding position closer to the developing cartridge 1 than the retracted position. FIG. 4 shows a state in which the pressing shaft 102 is located at the retracted position, and FIG. 5 shows a state in which the pressing shaft 102 is located at the protruding position. When performing a separating operation, the image forming apparatus 100 moves the pressing shaft 102 from the retracted position to the protruding position. This causes the pressing shaft 102 to come into contact with the second cam 52. Then, the pressing shaft 102 presses the separating shaft 50 in the first direction, in a direction from the first cam 51 to the second cam 52. Then, the spring 55 contracts, and the separating shaft 50 moves in the first direction from the first position to the second position relative to the housing 10.

[0053] When the separating shaft 50 moves from the first position to the second position, the first inclined surface 511 of the first cam 51 moves in the first direction while contacting the frame of the drum unit 2. At this time, the first cam 51 moves in the second direction relative to the drum unit 2 due to the resistance force received from the frame of the drum unit 2. More specifically, the first cam 51 moves in a direction away from the photosensitive drum 70 relative to the drum unit 2 due to the resistance force received from the frame of the drum unit 2.

[0054] Similarly, when the separating shaft 50 moves from the first position to the second position, the second inclined surface 521 of the second cam 52 moves in the first direction while contacting the frame of the drum unit 2. At this time, the second cam 52 moves in the second direction relative to the drum unit 2 due to the resistance force received from the frame of the drum unit 2. More specifically, the second cam 52 moves in a direction away from the photosensitive drum 70 relative to the drum unit 2 due to the resistance force received from the frame of the drum unit 2.

[0055] As a result, the housing 10 and the developing roller 20 move together with the separating shaft 50 in the second direction relative to the drum unit 2. More specifically, the housing 10 and the developing roller 20 move in a direction away from the photosensitive drum 70 relative to the drum unit 2. As a result, the developing roller 20 moves in the second direction from a contact position where it contacts the photosensitive drum 70 to a separated position where it is separated from the photosensitive drum 70.

[0056] <4. Protective cover> Next, a description will be given of the protective cover that is attached to the developing cartridge 1 when the developing cartridge 1 is transported. The developing cartridge 1 of this embodiment includes a first protective cover 80 and a second protective cover 90.

[0057] Fig. 6 is a perspective view of the developing cartridge 1 with the first protective cover 80 and the second protective cover 90 attached. Fig. 7 is a perspective view of the developing cartridge 1 in the vicinity of the first protective cover 80. Figs. 6 and 7 show a state in which the spacing shaft 50 is disposed at the first position. Fig. 8 is a perspective view of the developing cartridge 1 with the first protective cover 80 and the second protective cover 90 attached. Fig. 9 is a perspective view of the developing cartridge 1 in the vicinity of the first protective cover 80. Figs. 8 and 9 show a state in which the spacing shaft 50 is disposed at the second position.

[0058] The first protective cover 80 is an example of a "protective cover." The first protective cover 80 is detachable from the first outer surface 11 of the housing 10. When the developing cartridge 1 is transported, the first protective cover 80 is attached to the first outer surface 11. When the developing cartridge 1 is used, the first protective cover 80 is removed from the first outer surface 11.

[0059] The first protective cover 80 is made of a flexible resin such as polypropylene, etc. As shown in Fig. 7, the first protective cover 80 has a cover body 81, a cylindrical portion 82, two arms 83, and two claws 84.

[0060] The cover body 81 is cup-shaped and opens toward the housing 10 in the first direction. When the first protective cover 80 is attached to the first outer surface 11 of the housing 10, the cover body 81 covers the memory 41 and the holder 42. This protects the memory 41 and the holder 42 when the developing cartridge 1 is transported. Specifically, the holder 42 is prevented from moving relative to the housing 10 when the developing cartridge 1 is transported. In addition, it is possible to prevent the electrical contact surface 411 of the memory 41 from rubbing against a carrying case, bag, or the like when the developing cartridge 1 is transported.

[0061] The cylindrical portion 82 is located on the outer surface of the cover body 81. The cylindrical portion 82 is cylindrical and extends in a first direction. In a state where the first protective cover 80 is attached to the first outer surface 11 of the housing 10, the cylindrical portion 82 faces the spaced shaft 50 in the first direction. In a state where the spaced shaft 50 is arranged in the first position, the protruding shaft 54 ​​of the spaced shaft 50 is not inserted into the cylindrical portion 82 as shown in FIG. 7. On the other hand, when the spaced shaft 50 is arranged in the second position, the protruding shaft 54 ​​of the spaced shaft 50 is inserted into the cylindrical portion 82 as shown in FIG. 9. As a result, the protruding shaft 54 ​​is protected by the cylindrical portion 82.

[0062] The arm 83 extends in a first direction from the outer surface of the cylindrical portion 82 toward the separation shaft 50. The claw 84 protrudes from the tip of the arm 83 in a direction intersecting the first direction. When the separation shaft 50 is disposed at the first position, the first cam 51 is located closer to the other end of the housing 10 than the claw 84 in the first direction, as shown in FIG. 7. That is, when the separation shaft 50 is disposed at the first position, the first cam 51 is located on the opposite side of the arm 83 with respect to the claw 84 in the first direction. At this time, the claw 84 and the separation shaft 50 are separated from each other. The claw 84 faces the first inclined surface 511 of the first cam 51 in the first direction.

[0063] When the spacing shaft 50 moves from the first position to the second position with the first protective cover 80 attached to the housing 10, the first inclined surface 511 of the first cam 51 comes into contact with the two claws 84. When the spacing shaft 50 further moves toward the second position, the arm 83 bends, widening the gap between the two claws 84. This causes the first cam 51 to pass between the two claws 84. As a result, it becomes possible to move the spacing shaft 50 to the second position.

[0064] 9, when the spacing shaft 50 is disposed at the second position, the first cam 51 is located on the opposite side of the claw 84 from the other end of the housing 10 in the first direction. In other words, when the spacing shaft 50 is disposed at the second position, the first cam 51 is located on the same side as the arm 83 with respect to the claw 84 in the first direction. A portion of the outer surface of the first cam 51 is covered by the two arms 83 and the two claws 84.

[0065] 9, when the external force pressing the spacing shaft 50 toward the second position is removed, the elastic force of the spring 55 urges the spacing shaft 50 in the first direction toward the first position. Then, the first cam 51 contacts the pawl 84. That is, the first cam 51 and the pawl 84 engage with each other. This holds the spacing shaft 50 at the second position so that the spacing shaft 50 does not move from the second position to the first position. Therefore, the spacing shaft 50 is prevented from moving in the first direction when the developing cartridge 1 is transported.

[0066] The second protective cover 90 is detachable from one end of the housing 10 in the second direction. When the developing cartridge 1 is transported, the first protective cover 80 is attached to one end of the housing 10 in the second direction. When the developing cartridge 1 is used, the first protective cover 80 is removed from one end of the housing 10 in the second direction.

[0067] The second protective cover 90 is made of a flexible resin such as polypropylene. The second protective cover 90 is cup-shaped and opens toward the housing 10 in the second direction. When the second protective cover 90 is attached to the housing 10, the second protective cover 90 covers the developing roller 20. This protects the developing roller 20 when the developing cartridge 1 is transported.

[0068] As shown in Figs. 6 and 8, the second protective cover 90 has two ribs 91. The two ribs 91 are arranged at an interval in the first direction. Each rib 91 protrudes outward from the outer surface of the second protective cover 90. This prevents the cup-shaped second protective cover 90 from bending in a direction that opens outward. This prevents the second protective cover 90 from coming off the housing 10 during transportation of the developing cartridge 1.

[0069] Furthermore, the amount of resin used for second protective cover 90 can be reduced compared to when second protective cover 90 as a whole has the same thickness as rib 91 .

[0070] FIG. 10 is a cross-sectional view of the developing cartridge 1 with the second protective cover 90 attached, perpendicular to the first direction. As shown in FIGS. 7, 9, and 10, the second protective cover 90 has a surface cover portion 92 and a bent portion 93. When the second protective cover 90 is attached to the developing cartridge 1, the surface cover portion 92 spreads along the outer surface of the housing 10. The bent portion 93 bends at an acute angle from the end of the surface cover portion 92 in the second direction toward the outside of the housing 10. In addition, the bent portion 93 contacts a step portion formed on the outer surface of the housing 10. This further suppresses the second protective cover 90 from bending in a direction that opens outward. Therefore, it is possible to further suppress the second protective cover 90 from coming off the housing 10 during transportation of the developing cartridge 1.

[0071] At the time of shipping after manufacturing the developing cartridge 1, the first protective cover 80 and the second protective cover 90 are attached to the developing cartridge 1. Then, the separating shaft 50 is disposed at the second position. Then, the claw 84 of the first protective cover 80 holds the separating shaft 50 at the second position. Thereafter, the developing cartridge 1 with the first protective cover 80 and the second protective cover 90 attached is housed in a pouch bag and sealed.

[0072] In this way, the separation shaft 50 is prevented from moving in the first direction relative to the housing 10 of the developing cartridge 1 inside the pouch bag. Therefore, the pouch bag is prevented from being pushed by the movement of the separation shaft 50. In addition, the first protective cover 80 is prevented from coming off the housing 10 by the movement of the separation shaft 50.

[0073] With the spacing shaft 50 disposed at the second position, it is desirable that the other end of the spacing shaft 50 in the axial direction be located closer to the housing 10 than the end of the side cover 31 that is farthest from the housing 10 in the axial direction. In this way, it is possible to prevent the other end of the spacing shaft 50 in the axial direction from protruding from the outer surface of the side cover 31. Therefore, it is possible to further prevent the pouch bag from being pushed by the other end of the spacing shaft 50 in the axial direction.

[0074] In addition, when a used developer cartridge 1 is transported for recycling, for example, when the used developer cartridge 1 is transported to the manufacturer, the first protective cover 80 and the second protective cover 90 may be attached to the developer cartridge 1. In that case, it is desirable that the separation shaft 50 is disposed in the second position, as in the case of shipping the developer cartridge 1. However, in this embodiment, as shown in FIG. 6 and FIG. 7, even when the separation shaft 50 is disposed in the first position, the first protective cover 80 can be attached to the housing 10. Therefore, even if a user forgets to dispose the separation shaft 50 in the second position when sending the used developer cartridge 1 for recycling, the first protective cover 80 can be attached to the housing 10 to protect the memory 41.

[0075] <5. Modifications> Although one embodiment has been described above, the present disclosure is not limited to the above embodiment.

[0076] In the above embodiment, the developer cartridge 1 is provided with two protective covers, the first protective cover 80 and the second protective cover 90. However, the developer cartridge 1 does not necessarily have to be provided with the second protective cover 90. In addition, the developer cartridge 1 may be provided with a protective cover other than the first protective cover 80 and the second protective cover 90.

[0077] In the above embodiment, the number of developer cartridges 1 that can be attached to the drum unit 2 is four. However, the number of developer cartridges 1 that can be attached to the drum unit 2 may be one to three, or may be five or more.

[0078] In addition, the detailed shape and structure of the developing cartridge may be appropriately changed without departing from the spirit of the present invention. Furthermore, the elements appearing in the above embodiment and modified examples may be appropriately selected without departing from the spirit of the present invention. [Explanation of symbols]

[0079] 1: Developing cartridge 2: Drum unit 10: Housing 20: Developing roller 30: Gear section 31: Side cover 40: Memory Assembly 41: Memory 50: Spaced shaft 51: First Cam 52: Second Cam 53: Shaft body 54: Protruding shaft 55: Spring 70: Photoconductor drum 80: First protective cover 81: Cover body 82: Cylindrical part 83: Arm 84: Nails 100: Image forming apparatus 101: Main frame

Claims

1. A housing capable of accommodating toner; a developing roller rotatable about an axially extending developing shaft; a shaft movable in the axial direction between a first position and a second position relative to the housing, the shaft extending in the axial direction; a protective cover covering a portion of the shaft when the shaft is disposed at the second position, the protective cover having a claw that engages with the shaft when the shaft is disposed at the second position and holds the shaft at the second position so as not to move from the second position to the first position; A developing cartridge comprising:

2. 2. The developing cartridge according to claim 1, The developing cartridge, wherein the protective cover is detachable from the housing.

3. 3. The developing cartridge according to claim 2, A memory located at one end of the housing in the axial direction Further equipped with The developing cartridge, wherein the protective cover covers the memory when the developing cartridge is attached to the housing.

4. 4. The developing cartridge according to claim 1, The protective cover is An arm extending in the axial direction toward the shaft Further equipped with The developing cartridge, wherein the claw protrudes from the arm in a direction intersecting with the axial direction.

5. 5. The developing cartridge according to claim 4, The shaft is A cam located at one end in the axial direction having a developing cartridge, wherein the claw engages with the cam when the shaft is disposed at the second position.

6. 6. The developing cartridge according to claim 5, A spring biases the shaft from the second position toward the first position. Further equipped with a developing cartridge, wherein the pawl and the cam are in contact with each other in the axial direction when the shaft is disposed at the second position.

7. 6. The developing cartridge according to claim 5, The cam is An inclined surface inclined with respect to the axial direction having a developing cartridge, wherein the inclined surface comes into contact with the claw when the shaft moves from the first position to the second position.

8. 6. The developing cartridge according to claim 5, The shaft is A protruding shaft protruding from the cam toward one end of the shaft in the axial direction. and The protective cover is a cylindrical portion into which the protruding shaft is inserted when the shaft is disposed at the second position; The developing cartridge further comprises:

9. 4. The developing cartridge according to claim 3, a side cover covering the other end of the housing in the axial direction Further equipped with A developing cartridge characterized in that, when the shaft is positioned at the second position, the other end of the shaft in the axial direction is located closer to the housing than the end of the side cover that is farthest from the housing in the axial direction.

10. 4. The developing cartridge according to claim 2, A developing cartridge, wherein the protective cover is attachable to the housing when the shaft is disposed at the first position.

11. 4. The developing cartridge according to claim 1, The ink cartridge can be attached to a drum unit having a photosensitive drum. A developing cartridge characterized in that, when the developing cartridge is attached to the drum unit and the shaft moves from the first position to the second position, the developing roller moves from a contact position in contact with the photosensitive drum to a separated position away from the photosensitive drum.

12. 4. The developing cartridge according to claim 1, A developing cartridge, wherein the claw and the shaft are spaced apart when the shaft is disposed at the first position.

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