Development cartridge

Abstract

To provide a structure capable of suppressing the rubbing of an electric contact surface when a development cartridge is mounted.SOLUTION: A development cartridge 1 includes a housing 10 for accommodating a developer therein; a storage medium 61 having an electric contact surface 611; a holder 62 for holding the electric contact surface 611; and an elastic member 73. The elastic member 73 can be extended and contracted in a first direction between a first state and a second state more contracted than the first state. The outer surface which holds the electric contact surface 611 of the holder 62 is arranged at a first position when the elastic member 73 is in the first state, and is arranged at a second position when the elastic member 73 is in the second state. In this manner, the position of the outer surface of the holder 62 by which the electric contact surface 611 is held is changed in a first direction. As a result, when the development cartridge 1 is mounted, the rubbing of the electric contact surface 611 can be suppressed.SELECTED DRAWING: Figure 11

Description

[Technical field]

[0001] The present invention relates to a developing cartridge. [Background technology]

[0002] Conventionally, electrophotographic image forming devices such as laser printers and LED printers are known. A developing cartridge is used in the image forming device. The developing cartridge has a developing roller for supplying toner. The developing cartridge described in Patent Document 1 is attached to a drawer unit. The drawer unit is housed inside the image forming device and is pulled out from the image forming device. The drawer unit has a photosensitive drum. When the developing cartridge is attached to the drawer unit, the photosensitive drum and the developing roller face each other.

[0003] The developing cartridge described in Patent Document 2 is mounted in a drum cartridge. The drum cartridge has a photosensitive drum. When the developing cartridge is mounted in the drum cartridge, the photosensitive drum and the developing roller face each other. Then, with the developing cartridge mounted in the drum cartridge, the developing cartridge is mounted in an image forming device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-59510 A [Patent Document 2] JP 2013-54058 A Summary of the Invention [Problem to be solved by the invention]

[0005] Conventionally, a developer cartridge having a storage medium is also known. The storage medium is, for example, an IC chip. The storage medium has an electrical contact surface. The electrical contact surface contacts an electrical connector provided in an image forming device or a drawer unit. However, when the developer cartridge is attached to the image forming device or the drawer unit, the electrical contact surface rubs against a protrusion of the image forming device or the drawer unit.

[0006] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a structure capable of suppressing rubbing of electrical contact surfaces when a developing cartridge is mounted. [Means for solving the problem]

[0007] In order to solve the above problem, the first invention of the present application is a developing cartridge comprising a housing that contains a developer internally, a storage medium having an electrical contact surface, an elastic member extending in a first direction intersecting the electrical contact surface, the elastic member being expandable and contractible in the first direction between a first state and a second state, and a holder in which the electrical contact surface is located on an outer surface in the first direction, the position of the outer surface relative to the housing being movable in the first direction between a first position and a second position, wherein the length of the elastic member in the first state is longer than the length of the elastic member in the first direction in the second state, and when the elastic member is in the first state, the holder is located at the first position, and when the elastic member is in the second state, the holder is located at the second position.

[0008] The second invention of the present application is a developing cartridge of the first invention, wherein the holder includes a first end including the outer surface and a second end separated from the first end in the first direction, and the elastic member is positioned between the first end and the second end in the first direction.

[0009] A third invention of the present application is a developing cartridge of the second invention, wherein the distance in the first direction between the first end and the second end in the first state is longer than the distance in the first direction between the first end and the second end in the second state.

[0010] A fourth invention of the present application is a developing cartridge of any one of the first to third inventions, wherein the position of the outer surface relative to the housing is movable in the first direction between the first position, the second position, and the third position, the elastic member is expandable and contractible in the first direction between the first state, the second state, and the third state, the length of the elastic member in the first direction in the first state is longer than the length of the elastic member in the first direction in the second state, the length of the elastic member in the first direction in the third state is longer than the length of the elastic member in the first direction in the second state, and when the elastic member is in the third state, the holder is located at the third position.

[0011] A fifth invention of the present application is a developing cartridge of the second invention, wherein a position of the outer surface relative to the housing is movable in the first direction between the first position, the second position, and a third position, the elastic member is expandable and contractible in the first direction between the first state, the second state, and the third state, the length of the elastic member in the first direction in the first state is longer than the length of the elastic member in the second state, and the distance in the first direction between the first end and the second end in the first state is longer than the distance in the first direction between the first end and the second end in the second state, the length of the elastic member in the first direction in the third state is longer than the length of the elastic member in the first direction in the second state, and the distance in the first direction between the first end and the second end in the third state is longer than the distance in the first direction between the first end and the second end in the second state, and when the elastic member is in the third state, the holder is located at the third position.

[0012] The sixth invention of the present application is a developing cartridge according to any one of the first to fifth inventions, wherein the position of the outer surface relative to the housing is movable from the first position to the second position depending on the installation of the developing cartridge to an image forming device, and in the first position, a portion of the holder and the electrical contact surface are in a non-contact state where they do not contact a portion of the image forming device, and in the second position, a portion of the holder or the electrical contact surface is in a contact state where they contact the portion of the image forming device.

[0013] The seventh invention of the present application is a developing cartridge according to the fourth or fifth invention, wherein the position of the outer surface relative to the housing is movable from the first position via the second position to the third position depending on the installation of the developing cartridge to an image forming device, and at the first position, a portion of the holder and the electrical contact surface are in a non-contact state where they do not contact a portion of the image forming device, at the second position, a portion of the holder or the electrical contact surface is in a contact state where they contact a portion of the image forming device, and at the third position, the electrical contact surface is in a connector contact state where it contacts an electrical connector of the image forming device.

[0014] An eighth aspect of the present invention is the developing cartridge according to the fourth, fifth or seventh aspect, wherein the length of the elastic member in the first direction in the third state is shorter than a natural length of the elastic member.

[0015] A ninth aspect of the present invention is the developing cartridge according to any one of the first to eighth aspects, wherein the first direction is a direction perpendicular to the electrical contact surface.

[0016] A tenth aspect of the present invention is the developing cartridge according to any one of the first to ninth aspects, wherein the holder is movable together with the storage medium.

[0017] An eleventh aspect of the present invention is the developing cartridge according to any one of the first to tenth aspects, wherein the holder holds the electrical contact surface on the outer surface.

[0018] A twelfth aspect of the present invention is the developing cartridge according to any one of the first to eleventh aspects, wherein the storage medium is located on an outer surface of the holder.

[0019] A thirteenth aspect of the present invention is the developing cartridge according to the twelfth aspect, wherein the holder holds the storage medium on the outer surface.

[0020] A fourteenth aspect of the present invention is the developing cartridge according to any one of the first to thirteenth aspects of the present invention, further comprising a developing roller rotatable about a shaft extending in a direction different from the first direction.

[0021] A fifteenth aspect of the present invention is the developing cartridge according to any one of the first to fourteenth aspects, wherein the holder is located on a side of the housing.

[0022] The 16th invention of the present application is a developing cartridge of any one of the 1st to 15th inventions, wherein the outer surface has a first surface located on one side of the electrical contact surface in a second direction different from the first direction, and the first surface is inclined with respect to the electrical contact surface.

[0023] The 17th invention of the present application is a developing cartridge of the 16th invention, further comprising a developing roller rotatable about an axis extending in a third direction different from the first direction, the developing roller being located on one side of the housing in the second direction.

[0024] The 18th invention of the present application is a developing cartridge of the 16th or 17th invention, wherein the first surface extends from a third position toward the electrical contact surface to a fourth position, and in the first direction, the third position is farther from the electrical contact surface than the fourth position.

[0025] A 19th invention of the present application is a developing cartridge of the 18th invention, wherein the distance in the first direction between the third position and the fourth position is greater than the distance in the first direction between the electrical contact surface and the fourth position.

[0026] The 20th invention of the present application is a developing cartridge of any one of the 16th to 19th inventions, wherein the first surface is a first guide surface that can contact a part of the image forming device when the developing cartridge is attached to the image forming device.

[0027] The 21st invention of the present application is a developing cartridge of any one of the 16th to 20th inventions, wherein the outer surface has a second surface located on the other side of the electrical contact surface in the second direction, and the second surface is inclined with respect to the electrical contact surface.

[0028] The 22nd invention of the present application is a developing cartridge of the 21st invention, further comprising a developing roller rotatable about an axis extending in a third direction different from the first direction, the developing roller being located on one side of the housing in the second direction.

[0029] The 23rd invention of the present application is a developing cartridge of the 21st or 22nd invention, wherein the second surface extends from a fifth position toward the electrical contact surface to a sixth position, and in the first direction, the fifth position is farther from the electrical contact surface than the sixth position.

[0030] The 24th invention of the present application is a developing cartridge of the 23rd invention, wherein the distance in the first direction between the fifth position and the sixth position is greater than the distance in the first direction between the electrical contact surface and the sixth position.

[0031] The 25th invention of the present application is a developing cartridge of any one of the 21st to 24th inventions, wherein the second surface is a second guide surface that can contact a part of the image forming device when the developing cartridge is attached to the image forming device.

[0032] The 26th invention of the present application is a developing cartridge of any one of the 1st to 25th inventions, wherein the outer surface has third surfaces located on both sides of the electrical contact surface in a third direction different from the first direction, and in the first direction, the third surfaces are farther from the elastic member than the electrical contact surfaces.

[0033] A twenty-seventh aspect of the present invention is the developing cartridge of the twenty-sixth aspect, wherein the third surface is a third guide surface that can come into contact with a part of the image forming apparatus when the developing cartridge is attached to the image forming apparatus.

[0034] The 28th invention of the present application is a developing cartridge of the 26th or 27th invention, further comprising a developing roller rotatable about an axis extending in the third direction, the developing roller being located on one side of the housing in the second direction.

[0035] A twenty-ninth aspect of the present invention is the developing cartridge according to any one of the first to twenty-eighth aspects, wherein the elastic member is a spring.

[0036] A 30th aspect of the present invention is the developing cartridge of the 29th aspect, wherein the spring is a coil spring.

[0037] A thirty-first aspect of the present invention is the developing cartridge according to the twelfth or thirteenth aspect of the present invention, wherein the storage medium has the electrical contact surface. Effect of the Invention

[0038] According to the first to thirty-first aspects of the present application, it is possible to suppress abrasion of the electrical contact surfaces when the developing cartridge is mounted.

[0039] According to the second aspect of the present invention, an elastic member is provided between the first end and the second end of the holder, so that the first end including the outer surface can move in the first direction relative to the second end, thereby preventing friction of the electrical contact surfaces when the developer cartridge is attached to the image forming device.

[0040] According to the third aspect of the present invention, the distance in the first direction between the first end and the second end in the first state is longer than the distance in the first direction between the first end and the second end in the second state. Therefore, the distance of the first end, including the outer surface, can be changed relative to the second end. This makes it possible to suppress friction of the electrical contact surfaces when the developer cartridge is attached to the image forming device.

[0041] According to the fourth aspect of the present invention, the position of the outer surface of the holder that holds the electrical contact surface can be further moved from the second position to the third position in the first direction, thereby preventing friction of the electrical contact surface when the developer cartridge is attached to the image forming apparatus.

[0042] According to the fifth aspect of the present invention, an elastic member is provided between the first end and the second end of the holder, so that the first end including the outer surface can move in the first direction relative to the second end, and the position of the outer surface of the holder that holds the electrical contact surface can be further changed from a second position to a third position in the first direction. This makes it possible to suppress rubbing of the electrical contact surface when the developer cartridge is attached to the image forming apparatus.

[0043] In addition, according to the sixth invention of the present application, even if the holder is capable of contacting a part of the image forming device, the holder is capable of moving from the first position to the second position, thereby suppressing friction of the electrical contact surfaces when the developing cartridge is attached to the image forming device.

[0044] According to the seventh aspect of the present invention, the position of the outer surface of the holder on which the electrical contact surface is held can be further moved in the first direction from the second position to the third position, and at the third position, the electrical contact surface can come into contact with the electrical connector of the image forming device. This prevents friction on the electrical contact surface when the developer cartridge is attached to the image forming device, and allows the electrical contact to come into contact with the electrical connector of the image forming device.

[0045] Furthermore, according to the eighth invention of the present application, the length of the elastic member in the first direction in the third state is shorter than the natural length of the elastic member, so that in the third position, the electrical contact surface can receive the repulsive force of the elastic member.

[0046] Furthermore, according to the tenth aspect of the present invention, the storage medium can also be moved together with the holder.

[0047] Furthermore, according to the eleventh aspect of the present invention, the holder can hold the electrical contact surface on the outer surface.

[0048] Also, according to a twelfth aspect of the present invention, the storage medium can be located on the outer surface.

[0049] According to the thirteenth aspect of the present invention, the holder can hold the storage medium on the outer surface.

[0050] In addition, according to the 16th invention of the present application, by having a first surface that is inclined with respect to the electrical contact surface, the first surface can guide the holder when the developing cartridge is attached to or detached from the image forming device.

[0051] In addition, according to the 18th invention of the present application, by having a first surface that is inclined with respect to the electrical contact surface, the first surface can guide the holder when the developing cartridge is attached to or detached from the image forming device.

[0052] In addition, according to the 19th invention of the present application, by having a first surface inclined with respect to the electrical contact surface, the first surface can guide the holder when the developer cartridge is attached to or detached from the image forming device.

[0053] In addition, according to the 20th invention of the present application, by having a first guide surface that is inclined with respect to the electrical contact surface, the holder can be guided by the first guide surface when the developing cartridge is attached to or detached from the image forming device.

[0054] In addition, according to the 21st invention of the present application, by having a second surface inclined with respect to the electrical contact surface, the second surface can guide the holder when the developing cartridge is attached to or detached from the image forming device.

[0055] In addition, according to the 23rd invention of the present application, by having a second surface inclined with respect to the electrical contact surface, the second surface can guide the holder when the developer cartridge is attached to or detached from the image forming device.

[0056] In addition, according to the 24th invention of the present application, by having a second surface inclined with respect to the electrical contact surface, the second surface can guide the holder when the developing cartridge is attached to or detached from the image forming device.

[0057] In addition, according to the 25th invention of the present application, by having a second guide surface inclined with respect to the electrical contact surface, the second guide surface can guide the holder when the developing cartridge is attached to or detached from the image forming device.

[0058] In addition, according to the 26th invention of the present application, by having a third surface that is inclined with respect to the electrical contact surface, when the developing cartridge is attached to or detached from the image forming device, the third surface can suppress rubbing of the electrical contact surface when the developing cartridge is attached to or detached from the image forming device.

[0059] In addition, according to the 27th invention of the present application, by having a third guide surface that is inclined with respect to the electrical contact surface, when the developing cartridge is attached to or detached from the image forming device, the third guide surface can suppress rubbing of the electrical contact surface when the developing cartridge is attached to the image forming device.

[0060] According to the twenty-eighth aspect of the present invention, when the developer cartridge is attached to the image forming apparatus, the protrusions of the image forming apparatus do not come into contact with the electrical contact surfaces, which makes it possible to further prevent damage to the electrical contact surfaces. [Brief description of the drawings]

[0061] [Figure 1] FIG. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] FIG. [Figure 6] FIG. 2 is an exploded perspective view of an IC chip assembly. [Figure 7] FIG. 2 is a cross-sectional view of an IC chip assembly. [Figure 8] FIG. 4 illustrates a state in which the developing cartridge is being mounted. [Figure 9] FIG. 4 illustrates a state in which the developing cartridge is being mounted. [Figure 10] FIG. 4 illustrates a state in which the developing cartridge is being mounted. [Figure 11] FIG. 4 illustrates a state in which the developing cartridge is being mounted. [Figure 12] FIG. 4 illustrates a state in which the developing cartridge is being mounted. [Figure 13] FIG. 4 illustrates a state in which the developing cartridge is being mounted. [Figure 14] FIG. 4 illustrates a state in which the developing cartridge is being mounted. [Figure 15] 13A and 13B are diagrams illustrating a state when a separating operation is performed. [Figure 16] FIG. 11 is a partially exploded perspective view of a developing cartridge according to a first modified example. [Figure 17] FIG. 11 is a cross-sectional view of an IC chip assembly according to a first modified example. [Figure 18] FIG. 11 is a partial perspective view of a developing cartridge according to a second modified example. [Figure 19] 13A to 13C are diagrams showing the movements of the columnar elastic body and the IC chip assembly of the second modified example. [Figure 20] 13A to 13C are diagrams showing the movements of the columnar elastic body and the IC chip assembly of the second modified example. [Figure 21] 13A and 13B are diagrams illustrating a state in which a developing cartridge according to a second modified example is attached. [Figure 22] 13A and 13B are diagrams illustrating a state in which a developing cartridge according to a second modified example is attached. [Diagram 23] 13A and 13B are diagrams illustrating a state in which a separating operation of the developing cartridge of the second modified example is performed. [Figure 24] FIG. 13 is a perspective view of a developing cartridge according to a third modified example. [Diagram 25] FIG. 13 is a view of a developing cartridge according to a third modified example, as viewed from one side in a third direction. [Figure 26] FIG. 13 is a view of a developing cartridge according to a third modified example, as viewed from one side in a third direction. [Figure 27] FIG. 13 is a view of a developing cartridge according to a third modified example, as viewed from one side in a third direction. [Figure 28] FIG. 13 is an exploded perspective view of a first cover and an IC chip assembly according to a fourth modified example. [Figure 29] FIG. 13 is a cross-sectional view of a first cover and an IC chip assembly according to a fourth modified example. [Diagram 30] FIG. 13 is a perspective view of an IC chip assembly according to a fourth modified example. [Diagram 31] FIG. 13 is a partial perspective view of a developing cartridge according to a fifth modified example. [Diagram 32] FIG. 13 is an exploded perspective view of a first cover and an IC chip assembly according to a fifth modified example. [Diagram 33] FIG. 13 is a perspective view of a developing cartridge and a drum cartridge according to a sixth modified example. [Diagram 34] 13A and 13B are diagrams illustrating a state in which a drum cartridge according to a sixth modified example is mounted in an image forming apparatus. [Diagram 35] FIG. 13 is an exploded perspective view of the vicinity of an IC chip assembly according to a sixth modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0062] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[0063] In the following, the direction intersecting the electrical contact surface (in this embodiment, the direction perpendicular to the electrical contact surface) is referred to as the "first direction." The direction in which the casing 10 moves during a separation operation, which will be described later, is referred to as the "second direction." The direction in which the rotation axis of the developing roller extends is referred to as the "third direction."

[0064] <1. Overall structure of the developing cartridge> 1 to 5 are perspective views of a developing cartridge 1 according to an embodiment of the present invention. The developing cartridge 1 is used in an electrophotographic image forming apparatus (e.g., a laser printer or an LED printer) and is a unit that supplies a developer (e.g., toner) to a photosensitive drum. As shown in FIG. 1, the developing cartridge 1 of this embodiment is attached to a drawer unit 90 of the image forming apparatus. When replacing the developing cartridge 1, the drawer unit 90 is pulled out from the front of the image forming apparatus. Then, the developing cartridges 1 are attached to four cartridge holding sections 91 provided in the drawer unit 90. A photosensitive drum is provided in each of the four cartridge holding sections 91.

[0065] In this embodiment, four developer cartridges 1 are attached to one drawer unit 90. The four developer cartridges 1 contain developers of different colors (for example, cyan, magenta, yellow, and black). However, the number of developer cartridges 1 attached to the drawer unit 90 may be one to three, or may be five or more.

[0066] As shown in FIGS. 2 to 5, the developing cartridge 1 of this embodiment includes a casing 10, an agitator 20, a developing roller 30, a first gear portion 40, a second gear portion 50, and an IC chip assembly 60. As shown in FIG.

[0067] The developing roller 30 is a roller that can rotate about a rotation axis that extends in the third direction. The developing roller 30 of this embodiment has a roller body 31 and a roller shaft 32. The roller body 31 is a cylindrical member that extends in the third direction. The roller body 31 is made of a material such as elastic rubber. The roller shaft 32 is a cylindrical member that penetrates the roller body 31 in the third direction. The roller shaft 32 is made of a material such as metal or conductive resin.

[0068] The roller shaft 32 does not have to penetrate the roller body 31 in the third direction. For example, a pair of roller shafts 32 may extend in the third direction from both ends of the roller body 31 in the third direction.

[0069] The agitator 20 has an agitator shaft 21 and an agitating blade 22. The agitator shaft 21 extends along a rotation axis extending in the third direction. The agitating blade 22 extends radially outward from the agitator shaft 21. The agitating blade 22 is disposed in the developer chamber 13 of the casing 10. A first agitator gear 44 and a second agitator gear 51, which will be described later, are respectively connected to both ends of the agitator shaft 21 in the third direction. Therefore, the agitator shaft 21 and the agitating blade 22 rotate together with the first agitator gear 44 and the second agitator gear 51. When the agitating blade 22 rotates, the developer in the developer chamber 13 is agitated.

[0070] 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 spaced apart from each other in a third direction. The first gear portion 40 and the IC chip assembly 60 are located on the first outer surface 11. The second gear portion 50 is located on the second outer surface 12. The casing 10 extends in the third direction between the first outer surface 11 and the second outer surface 12. A developer chamber 13 that contains a developer is provided inside the casing 10.

[0071] The casing 10 has an opening 14. The opening 14 connects the developer chamber 13 to the outside. The opening 14 is located at one end of the casing 10 in the second direction. The developing roller 30 is located at the opening 14. That is, the developing roller 30 is located on one side of the center of the casing 10 in the second direction. The roller body 31 is fixed to the roller shaft 32 so as not to rotate relative thereto. In addition, one end of the roller shaft 32 in the third direction is fixed to the developing gear 42 described later so as not to rotate relative thereto. Therefore, when the developing gear 42 rotates, the roller shaft 32 also rotates, and the roller body 31 rotates together with the roller shaft 32.

[0072] When the developing cartridge 1 receives a driving force, developer is supplied from the developer chamber 13 in the casing 10 to the outer circumferential surface of the developing roller 30 via a supply roller (not shown). At that time, the developer is frictionally charged between the supply roller and the developing roller 30. Meanwhile, a bias voltage is applied to the roller shaft 32 of the developing roller 30. Therefore, the developer is attracted to the outer circumferential surface of the roller body 31 by the electrostatic force between the roller shaft 32 and the developer.

[0073] The developing cartridge 1 also has a layer thickness regulating blade (not shown). The layer thickness regulating blade regulates the developer supplied to the outer peripheral surface of the roller body 31 to a constant thickness. The developer on the outer peripheral surface of the roller body 31 is then supplied to a photosensitive drum provided in the drawer unit 90. At this time, the developer moves from the roller body 31 to the photosensitive drum in accordance with the electrostatic latent image formed on the outer peripheral surface of the photosensitive drum. As a result, the electrostatic latent image is visualized on the outer peripheral surface of the photosensitive drum.

[0074] The first gear portion 40 is located on one side of the casing 10 in the third direction. That is, the first gear portion 40 is located on the first outer surface 11. FIG. 4 is a perspective view of the developing cartridge 1 with the first gear portion 40 disassembled. As shown in FIG. 4, the first gear portion 40 has a coupling 41, a developing gear 42, an idle gear 43, a first agitator gear 44, and a first cover 45. Note that in FIG. 4, the illustration of multiple gear teeth of each gear is omitted.

[0075] The coupling 41 is a gear that first receives a driving force supplied from the image forming apparatus. The coupling 41 is capable of rotating around a rotation axis extending in the third direction. The coupling 41 has a coupling portion 411 and a coupling gear 412. The coupling portion 411 and the coupling gear 412 are formed of, for example, an integral resin. The coupling portion 411 is provided with a fastening hole 413 recessed in the third direction. In addition, a plurality of gear teeth are provided at equal intervals around the outer periphery of the coupling gear 412.

[0076] When the drawer unit 90 with the developer cartridge 1 attached is stored in the image forming apparatus, the drive shaft of the image forming apparatus is inserted into the fastening hole 413 of the coupling part 411. This connects the drive shaft and the coupling part 411 so that they cannot rotate relative to each other. Therefore, when the drive shaft rotates, the coupling part 411 rotates, and the coupling gear 412 rotates together with the coupling part 411.

[0077] The developing gear 42 is a gear for rotating the developing roller 30. The developing gear 42 can rotate around a rotation axis extending in the third direction. A plurality of gear teeth are provided at equal intervals around the outer periphery of the developing gear 42. At least some of the gear teeth of the coupling gear 412 and at least some of the gear teeth of the developing gear 42 mesh with each other. The developing gear 42 is fixed to an end of the roller shaft 32 of the developing roller 30 in the third direction so as not to rotate relative to the developing gear 42. Therefore, when the coupling gear 412 rotates, the developing gear 42 rotates, and the developing roller 30 rotates together with the developing gear 42.

[0078] The idle gear 43 is a gear for transmitting the rotation of the coupling gear 412 to the first agitator gear 44. The idle gear 43 is capable of rotating around a rotation axis extending in the third direction. The idle gear 43 has a large diameter gear portion 431 and a small diameter gear portion 432 arranged in the third direction. The small diameter gear portion 432 is located between the large diameter gear portion 431 and the first outer surface 11 of the casing 10. In other words, the large diameter gear portion 431 is farther away from the first outer surface 11 than the small diameter gear portion 432. The diameter of the small diameter gear portion 432 is smaller than the diameter of the large diameter gear portion 431. In other words, the diameter of the tip circle of the small diameter gear portion 432 is smaller than the diameter of the tip circle of the large diameter gear portion 431. The large diameter gear portion 431 and the small diameter gear portion 432 are formed, for example, from an integral resin.

[0079] The large diameter gear portion 431 and the small diameter gear portion 432 each have a plurality of gear teeth at equal intervals around the entire circumference. The number of gear teeth of the small diameter gear portion 432 is smaller than the number of gear teeth of the large diameter gear portion 431. At least some of the gear teeth of the coupling gear 412 and at least some of the gear teeth of the large diameter gear portion 431 mesh with each other. At least some of the gear teeth of the small diameter gear portion 432 and at least some of the gear teeth of the first agitator gear 44 mesh with each other. When the coupling gear 412 rotates, the large diameter gear portion 431 rotates, and the small diameter gear portion 432 rotates together with the large diameter gear portion 431. The first agitator gear 44 also rotates with the rotation of the small diameter gear portion 432.

[0080] The first agitator gear 44 is a gear for rotating the agitator 20 in the developer chamber 13. The first agitator gear 44 can rotate around a rotation axis extending in the third direction. A plurality of gear teeth are provided at equal intervals around the outer periphery of the first agitator gear 44. As described above, at least some of the gear teeth of the small diameter gear portion 432 and at least some of the gear teeth of the first agitator gear 44 mesh with each other. The first agitator gear 44 is fixed to one end of the agitator shaft 21 in the third direction so as not to rotate relative to the agitator gear 20. Therefore, when power is transmitted from the coupling 41 to the first agitator gear 44 via the idle gear 43, the first agitator gear 44 rotates, and the agitator 20 rotates together with the first agitator gear 44.

[0081] The first cover 45 is fixed to the first outer surface 11 of the casing 10, for example, by screwing. The coupling gear 412, the developing gear 42, the idle gear 43, and the first agitator gear 44 are housed between the first outer surface 11 and the first cover 45. The fastening hole 413 of the coupling portion 411 is exposed to the outside of the first cover 45. The first cover 45 of this embodiment also serves as a holder cover that holds a holder 62 of an IC chip assembly 60, which will be described later. The structure of the first cover 45 as a holder cover will be described later.

[0082] The second gear portion 50 is located on the other side of the casing 10 in the third direction. That is, the second gear portion 50 is located on the second outer surface 12. FIG. 5 is a perspective view of the developing cartridge 1 with the second gear portion 50 disassembled. As shown in FIG. 5, the second gear portion 50 has a second agitator gear 51, a detection gear 52, a conductive member 53, and a second cover 54. Note that in FIG. 5, the gear teeth of the second agitator gear 51 and the detection gear 52 are omitted.

[0083] The second agitator gear 51 is a gear for transmitting the rotation of the agitator shaft 21 to the detection gear 52. The second agitator gear 51 can rotate around a rotation axis extending in the third direction. A plurality of gear teeth are provided at equal intervals around the outer periphery of the second agitator gear 51. At least some of the gear teeth of the second agitator gear 51 and at least some of the gear teeth of the detection gear 52 mesh with each other. The second agitator gear 51 is fixed to the other end of the agitator shaft 21 in the third direction so as not to rotate relative to each other. Therefore, when the agitator shaft 21 rotates, the second agitator gear 51 also rotates.

[0084] The detection gear 52 is a gear for transmitting information about the developer cartridge 1 to the image forming apparatus. The information about the developer cartridge 1 includes, for example, information about whether the developer cartridge 1 is a new (unused) developer cartridge or a used developer cartridge. The information about the developer cartridge 1 also includes, for example, specifications of the developer cartridge 1. The specifications of the developer cartridge 1 include, for example, the number of prints that can be printed with the developer contained in the developer cartridge 1 (yield number).

[0085] The detection gear 52 is capable of rotating around a rotation axis extending in the third direction. The detection gear 52 has a plurality of gear teeth on a portion of its outer periphery. When an unused developer cartridge 1 is attached to the drawer unit 90 and the drawer unit 90 is stored in the image forming apparatus, the detection gear 52 rotates by meshing with the second agitator gear 51. When the meshing between the second agitator gear 51 and the detection gear 52 is released, the detection gear 52 stops rotating.

[0086] On the other hand, when a used developer cartridge 1 is attached to the drawer unit 90 and the drawer unit 90 is stored in the image forming apparatus, the detection gear 52 does not rotate because the engagement between the detection gear 52 and the second agitator gear 51 is disengaged.

[0087] Note that another gear may be disposed between the second agitator gear 51 and the detection gear 52. For example, the second gear unit 50 may have a second idle gear that meshes with both the second agitator gear 51 and the detection gear 52. Then, the rotation of the second agitator gear 51 may be transmitted to the detection gear 52 via the second idle gear.

[0088] 5, the detection gear 52 has a detection protrusion 521. The detection protrusion 521 protrudes in a third direction. The detection protrusion 521 extends in an arc shape with the rotation axis as the center.

[0089] The conductive member 53 is a conductive member. A conductive metal or a conductive resin is used as the material of the conductive member 53. The conductive member 53 is located on the second outer surface 12 of the casing 10. The conductive member 53 has a gear shaft 531 protruding in the third direction. The detection gear 52 rotates around the gear shaft 531 while being supported by the gear shaft 531. The conductive member 53 also has a bearing portion 532. The bearing portion 532 contacts the roller shaft 32 of the developing roller 30.

[0090] The drawer unit 90 has a conductive lever (not shown) that contacts the gear shaft 531. When the lever contacts the gear shaft 531, the conductive member 53 and the roller shaft 32 are electrically connected to the lever. When the image forming apparatus is driven, the roller shaft 32 is maintained at a predetermined bias voltage by the power supplied from the lever. However, the detection protrusion 521 partially covers the outer circumferential surface of the gear shaft 531. Therefore, when the detection gear 52 rotates after a new developer cartridge 1 is inserted into the drawer unit 90, the contact state between the lever and the gear shaft 531 changes according to the shape of the detection gear 52. By recognizing the change in the contact state, the image forming apparatus identifies whether the installed developer cartridge 1 is new or not, and the specifications of the developer cartridge 1.

[0091] However, the method of detecting information from the detection gear 52 does not necessarily have to utilize the presence or absence of electrical conduction. For example, the movement of the lever may be optically detected. The circumferential position and length of the detection protrusion 521 may be different from those in this embodiment. The detection gear 52 may have a plurality of detection protrusions 521. The shape of the detection gear 52 can be varied according to the specifications of the developing cartridge 1, such as the number of printable sheets. Specifically, the number of detection protrusions 521, the circumferential intervals between the plurality of detection protrusions 521, the circumferential length of each detection protrusion 521, the radial length of each detection protrusion 521, and the like can be varied for each specification. In this way, by providing variations in the number and circumferential positions of the detection protrusions 521, it is possible to present various specifications of the developing cartridge 1 to the image forming apparatus.

[0092] The detection gear may be composed of multiple members. For example, the detection gear 52 and the detection protrusion 521 may be separate members. The detection gear may have a detection gear main body and an auxiliary member whose position changes in response to the rotation of the detection gear main body. The auxiliary member may change the position of the lever.

[0093] Furthermore, the detection gear 52 may be a movable gear that is movable in the third direction. The movable gear does not have to be a gear with missing teeth. That is, the movable gear may have a plurality of gear teeth arranged circumferentially on its outer circumferential surface. In this case, when the movable gear rotates, the movable gear moves toward the third direction, and the meshing between the movable gear and the second agitator gear 51 is released. The movable gear may move in a direction away from the second outer surface 12 in the third direction. The movable gear may move in a direction approaching the third direction from the second outer surface 12.

[0094] Furthermore, the detection gear 52 may have a cam, and the cam may come into contact with the detection protrusion 521. In this case, the cam rotates with the rotation of the detection gear 52, and the rotation of the cam brings the cam into contact with the detection protrusion 521, causing the detection protrusion 521 to move. The detection protrusion 521 may be rotatably attached to a shaft provided on the second outer surface 12 or the second gear cover 54. Furthermore, the shaft of the detection protrusion 521 may be inserted into a hole in the second outer surface 12 or the second gear cover 54, and the detection protrusion 521 may be rotatably held.

[0095] In this embodiment, the gear shaft 531 extends in the third direction from the second outer surface 12. However, the gear shaft 531 does not have to be in direct contact with the second outer surface 12. For example, the casing 10 may further have a through hole penetrating the second outer surface 12 and a cap attached to the through hole, and the gear shaft may extend from the cap in the third direction. In this case, for example, the cap has a gear shaft protruding in the third direction toward the detection gear 53. The detection gear 53 rotates around the gear shaft 531 while being supported by the gear shaft.

[0096] The second cover 54 is fixed to the second outer surface 12 of the casing 10, for example, by screwing. The second agitator gear 51, the detection gear 52, and the conductive member 53 are housed between the second outer surface 12 and the second cover 54. The second cover 54 also has an opening 541. A portion of the detection gear 52 and a portion of the gear shaft 531 are exposed through the opening 541. The above-mentioned lever comes into contact with the detection gear 52 or the gear shaft 531 through the opening 541.

[0097] <2. IC chip assembly> The IC chip assembly 60 is disposed on the first outer surface 11 of the casing 10. FIG. 6 is an exploded perspective view of the IC chip assembly 60. FIG. 7 is a cross-sectional view of the IC chip assembly 60 cut along a plane perpendicular to the third direction. As shown in FIGS. 2 to 7, the IC chip assembly 60 has an IC chip 61 which is a storage medium, and a holder 62 which holds the IC chip 61. The holder 62 is held by the first cover 45 at the side of the casing 10 in the third direction. Various information related to the developing cartridge 1 is recorded in the IC chip 61. The IC chip 61 has an electrical contact surface 611. The electrical contact surface 611 is made of a metal which is a conductor. The IC chip 61 is fixed to the outer surface of the holder 62 in the first direction.

[0098] The drawer unit 90 has an electrical connector. The electrical connector is made of, for example, metal. When the developing cartridge 1 is attached to the drawer unit 90, the electrical connector of the drawer unit 90 comes into contact with the electrical contact surface 611. This enables the image forming apparatus to at least one of read information from the IC chip 61 and write information to the IC chip 61.

[0099] At least a part of the holder 62 is covered by the first cover 45. The holder 62 has a boss 621a, a boss 621b, and a boss 621c. The boss 621a and the boss 621b each extend in the third direction from the surface of the holder 62 opposite to the surface facing the casing 10 toward the first cover 45. The boss 621a and the boss 621b are aligned in the second direction. On the other hand, as shown in FIG. 2 and FIG. 4, the first cover 45 has a through hole 451a and a through hole 451b. The through hole 451a and the through hole 451b each penetrate the first cover 45 in the third direction. The through hole 451a and the through hole 451b are aligned in the second direction. The boss 621a is inserted into the through hole 451a. The boss 621b is inserted into the through hole 451b.

[0100] Boss 621c extends in the third direction from a surface of holder 62 facing casing 10 toward casing 10. Meanwhile, casing 10 has recess 15. Recess 15 is recessed in the third direction in first outer surface 11 of casing 10. Boss 621c is inserted into recess 15. Note that each of bosses 621a, 621b, and 621c may have a cylindrical shape or a rectangular column shape.

[0101] The size (inner dimension) of the through hole 451a in the second direction is larger than the size (outer dimension) of the boss 621a in the second direction. The size (inner dimension) of the through hole 451b in the second direction is larger than the size (outer dimension) of the boss 621b in the second direction. In addition, the size (inner dimension) of the recess 15 in the second direction is larger than the size (outer dimension) of the boss 621c in the second direction. Therefore, the holder 62 can move in the second direction relative to the casing 10 and the first cover 45 together with the boss 621a, the boss 621b, and the boss 621c. When the holder 62 moves in the second direction, the IC chip 61 having the electrical contact surface 611 also moves in the second direction together with the holder 62.

[0102] Moreover, the size (inner dimension) of the through hole 451a in the first direction is larger than the size (outer dimension) of the boss 621a in the first direction. The size (inner dimension) of the through hole 451b in the first direction is larger than the size (outer dimension) of the boss 621b in the first direction. Moreover, the size (inner dimension) of the recess 15 in the first direction is larger than the size (outer dimension) of the boss 621c in the first direction. Therefore, the holder 62 can move in the first direction relative to the casing 10 and the first cover 45 together with the boss 621a, the boss 621b, and the boss 621c. When the holder 62 moves in the first direction, the IC chip 61 having the electrical contact surface 611 also moves in the first direction together with the holder 62. Moreover, the holder 62 may be movable in a third direction between the first cover 45 and the first outer surface 11.

[0103] The number of bosses provided on holder 62 may be one or more than two. The number of through holes provided on first cover 45 may be one or more than three. First cover 45 may have recesses into which bosses 621a and 621b are inserted, instead of through holes 451a and 451b.

[0104] As shown in FIG. 6 and FIG. 7, the holder 62 has a first end 710 and a second end 720. The first end 710 is one end of the holder 62 in the first direction. The second end 720 is the other end of the holder 62 in the first direction. The first end 710 is movable in the first direction relative to the second end 720. More specifically, the holder 62 of this embodiment has a first holder member 71, a second holder member 72, and a coil spring 73 located therebetween. The first holder member 71 is made of, for example, resin. The second holder member 72 is made of, for example, resin. The first holder member 71 has a first end 710. The IC chip 61 is fixed to a holding surface 620 included in the outer surface of the first end 710. The second holder member 72 has a second end 720. In the assembled holder 62, the first end 710 and the second end 720 are spaced apart in the first direction.

[0105] The coil spring 73 is an elastic member that extends in a first direction. The coil spring 73 is disposed between a first end 710 and a second end 720 in the first direction. The coil spring 73 expands and contracts in the first direction at least between a first state and a second state that is more contracted than the first state. The length of the coil spring 73 in the first state in the first direction is longer than the length of the coil spring 73 in the first state in the first direction. Therefore, the distance in the first direction between the first end 710 and the second end 720 in the first state is longer than the distance in the first direction between the first end 710 and the second end 720 in the second state. Moreover, the length of the coil spring 73 in the first direction at least in the second state is shorter than the natural length of the coil spring 73.

[0106] As shown in FIG. 6 and FIG. 7, the first holder member 71 has a claw portion 714a and a claw portion 714b. The claw portion 714a and the claw portion 714b each protrude from the first holder member 71 in a direction intersecting the first direction. On the other hand, the second holder member 72 has an opening 721a and an opening 721b. The claw portion 714a is inserted into the opening 721a. The claw portion 714b is inserted into the opening 721b. In the first state, the claw portion 714a contacts the second holder member 72 at the edge of the opening 721a on the first end 710 side. In the first state, the claw portion 714b contacts the second holder member 72 at the edge of the opening 721b on the first end 710 side. This prevents the length of the coil spring 73 in the first direction from becoming longer than in the first state. Furthermore, the first holder member 71 is prevented from being detached from the second holder member 72. On the other hand, in the second state, the claw portion 714a and the claw portion 714b are separated from the second holder member 72.

[0107] In place of the opening, a recess or a step that can come into contact with the claw may be provided. Also, the first holder member 71 may be provided with an opening, a recess or a step, and the second holder member 72 may be provided with the claw.

[0108] The holding surface 620 of the holder 62 can move in the first direction relative to the casing 10 due to the dimensional difference between the through hole 451 and the boss 621 and the expansion and contraction of the coil spring 73. Hereinafter, the position of the holding surface 620 in the first direction relative to the casing 10 before the developer cartridge 1 is attached to the drawer unit 90 is referred to as the "initial position" (first position). In addition, when the developer cartridge 1 is attached to the drawer unit 90, the position of the holding surface 620 in the first direction relative to the casing 10 at the moment when the coil spring 73 is most contracted is referred to as the "intermediate position" (second position). In addition, the position of the holding surface 620 in the first direction relative to the casing 10 when the electrical contact surface 611 contacts the electrical connector 913 described later is referred to as the "contact position" (third position). In addition, the position of the holding surface 620 in the first direction relative to the casing 10 after the attachment of the developer cartridge 1 to the drawer unit 90 is completed is referred to as the "final position" (fourth position).

[0109] In addition to the holding surface 620 described above, the outer surface of the first end 710 further has a first guide surface 711 (first surface), a second guide surface 712 (second surface), and third guide surfaces 713a, 713b (third surface).

[0110] The first guide surface 711 is provided on one of both side portions in the second direction of the holding surface 620, which is closer to the developing roller 30. The first guide surface 711 is inclined with respect to the electrical contact surface 611 of the IC chip 61 held on the holding surface 620. In detail, the first guide surface 711 is inclined with respect to the electrical contact surface 611 at an acute angle.

[0111] Here, one end of the first end 710 in the second direction is a first outer end position (third position) 711a. Also, one end of the holding surface 620 in the second direction is a first inner end position (fourth position) 711b. As shown in FIG. 7, the first guide surface 711 extends from the first outer end position 711a toward the electrical contact surface 611 to the first inner end position 711b. In both the second direction and the first direction, the first outer end position 711a is farther from the electrical contact surface 611 than the first inner end position 711b. Also, as shown in FIG. 7, the distance d1 in the first direction between the first outer end position 711a and the first inner end position 711b is greater than the distance d2 in the first direction between the electrical contact surface 611 and the first inner end position 711b.

[0112] The second guide surface 712 is provided on one of both side portions in the second direction of the holding surface 620, the other side farther from the developing roller 30. The second guide surface 712 is inclined with respect to the electrical contact surface 611 of the IC chip 61 held on the holding surface 620. In detail, the second guide surface 712 is inclined with respect to the electrical contact surface 611 at an acute angle.

[0113] Here, the other end of the first end 710 in the second direction is the second outer end position (fifth position) 712a. The other end of the holding surface 620 in the second direction is the second inner end position (sixth position) 712b. As shown in FIG. 7, the second guide surface 712 extends from the second outer end position 712a toward the electrical contact surface 611 to the second inner end position 712b. In both the second direction and the first direction, the second outer end position 712a is farther from the electrical contact surface 611 than the second inner end position 712b. Also, as shown in FIG. 7, the distance d3 in the first direction between the second outer end position 712a and the second inner end position 712b is greater than the distance d4 in the first direction between the electrical contact surface 611 and the second inner end position 712b.

[0114] The third guide surface 713a is provided on one of both sides of the electrical contact surface 611 in the third direction. The third guide surface 713b is provided on the other of both sides of the electrical contact surface 611 in the third direction. The third guide surface 713a and the third guide surface 713b each extend in the second direction. In addition, in the first direction, each of the third guide surfaces 713a and 713b is farther from the coil spring 73 than the electrical contact surface 611. Therefore, the electrical contact surface 611 is disposed at a position recessed toward the coil spring 73 side than the third guide surface 713a and the third guide surface 713b.

[0115] The first guide surface 711, the second guide surface 712, and the third guide surfaces 713a and 713b may each be flat or curved. However, it is preferable that the first guide surface 711, the second guide surface 712, and the third guide surfaces 713a and 713b are each a smooth surface without any steps so that the developer cartridge 1 does not get caught when it is attached to the drawer unit 90.

[0116] <3. Operation when worn> Next, there will be described an operation when the developing cartridge 1 is attached to the drawer unit 90. Figures 8 to 14 are diagrams showing a state when the developing cartridge 1 is attached to one cartridge holding portion 91 of the drawer unit 90.

[0117] When the developing cartridge 1 is mounted in the cartridge holding portion 91, first, as shown in FIG. 8, the developing roller 30 of the developing cartridge 1 faces the insertion port 910 of the cartridge holding portion 91. At this time, the first end 710 and the second end 720 of the holder 62 are not yet in contact with the drawer unit 90. Therefore, the coil spring 73 is in the first state described above. Also, the position of the holding surface 620 in the first direction relative to the casing 10 is in the initial position described above. The developing cartridge 1 is inserted in the second direction relative to the cartridge holding portion 91 as shown by the dashed arrow in FIG. 8.

[0118] The cartridge holding section 91 has a first guide plate 911 and a second guide plate 912. The first guide plate 911 and the second guide plate 912 are disposed facing each other with a gap in the first direction. The first guide plate 911 and the second guide plate 912 extend along the third direction and the second direction, respectively. The first guide plate 911 also has a metallic electrical connector 913 that can come into contact with the electrical contact surface 611 of the IC chip 61. The electrical connector 913 protrudes from the surface of the first guide plate 911 toward the second guide plate 912 in the first direction.

[0119] When the developing cartridge 1 is inserted into the cartridge holding portion 91, as shown in Fig. 9, the first guide surface 711 of the holder 62 comes into contact with the end of the first guide plate 911 in the second direction. Then, the first guide surface 711 is pressed by the first guide plate 911, causing the holder 62 to move in the first direction. The movement of the holder 62 at this time is a relative movement with respect to the casing 10. As a result, the holder 62 is positioned in the first direction between the first guide plate 911 and the second guide plate 912, as shown in Fig. 10.

[0120] Thereafter, the first end 710 of the first holder member 71 comes into contact with the first guide plate 911. Additionally, the second end 720 of the second holder member 72 comes into contact with the second guide plate 912. The coil spring 73 contracts in the first direction more than in the first state.

[0121] 11, the first guide plate 911 has a guide protrusion 914 that protrudes toward the second guide plate 912. The guide protrusion 914 is located closer to the insertion opening 910 than the electrical connector 913. The guide protrusion 914 has a first inclined surface 915. In addition, the second guide plate 912 has a second inclined surface 916. The distance in the first direction between the first inclined surface 915 and the second inclined surface 916 gradually becomes shorter toward the insertion direction of the developer cartridge 1.

[0122] When the developer cartridge 1 is further inserted in the second direction, the first holder member 71 contacts the first inclined surface 915, and the second holder member 72 contacts the second inclined surface 916. As a result, the first holder member 71 and the second holder member 72 approach each other in the first direction, and the length of the coil spring 73 in the first direction gradually shortens. Eventually, when the third guide surfaces 713a and 713b of the first holder member 71 contact the top of the guide protrusion 914, the length of the coil spring 73 in the first direction becomes the shortest. That is, the coil spring 73 is in the second state described above. Also, the position of the holding surface 620 in the first direction relative to the casing 10 becomes the intermediate position described above.

[0123] In this way, the IC chip assembly 60 can change the position of the holding surface 620 that holds the IC chip 61 in the first direction when the developer cartridge 1 is inserted into the drawer unit 90. Therefore, the developer cartridge 1 can be inserted while changing the position of the holding surface 620 in the first direction along the guide protrusion 914. Also, compared to the case where the guide protrusion 914 is passed while the position of the holding surface 620 in the first direction is fixed, the pressure in the first direction applied from the guide protrusion 914 to the first holder member 71 is reduced. Therefore, the developer cartridge 1 can be inserted into the drawer unit 90 while suppressing friction of the electrical contact surface 611 of the IC chip 61. Also, as shown in FIG. 10, FIG. 11, and FIG. 12, after the first surface 711 rides over the guide protrusion 914, the electrical contact surface 611 directly contacts the electrical connector 913. This can also reduce friction of the electrical connector 913.

[0124] In particular, in the developing cartridge 1 of this embodiment, the electrical contact surface 611 of the IC chip 61 is disposed at a position recessed from the third guide surfaces 713a, 713b. Therefore, in the state of FIG. 11, the top of the guide protrusion 914 contacts only the third guide surfaces 713a, 713b, and does not contact the electrical contact surface 11. Therefore, it is possible to prevent the guide protrusion 914 from rubbing against the electrical contact surface 611.

[0125] After that, when the developer cartridge 1 is further inserted in the second direction, the third guide surfaces 713a and 713b pass the guide protrusion 914. Then, as shown in FIG. 12, the second guide surface 712 comes into contact with the guide protrusion 914. Accordingly, the coil spring 73 expands again from the second state to the third state described above. As a result, as shown in FIG. 13, the electrical contact surface 611 of the IC chip 61 comes into contact with the electrical connector 913. The length of the coil spring 73 in the first direction in the third state is shorter than the length of the coil spring 73 in the first direction in the first state, and longer than the length of the coil spring 73 in the first direction in the second state. Also, the length of the coil spring 73 in the first direction in the third state is shorter than the natural length of the coil spring 73. Also, the relative position of the holding surface 620 in the first direction with respect to the casing 10 becomes the contact position described above.

[0126] As a result, the IC chip assembly 60 is fixed in a state where it is sandwiched between the electrical connector 913 and the second guide plate 912. After that, in this embodiment, as shown by the dashed arrow in FIG. 14, the casing 10 is tilted in the first direction. As a result, the developing roller 30 contacts the photosensitive drum 92 of the drawer unit 90. At this time, the position of the holding surface 620 in the first direction relative to the casing 10 changes from the contact position described above to the final position. Also, the boss 621 moves in the first direction within the through hole 451. As a result, the boss 621 is not in contact with the edge portion constituting the through hole 451 of the first cover 45. As a result, the IC chip assembly 60 and the first cover 45 are not in contact with each other. Therefore, during the execution of the printing process in the image forming apparatus, vibration is not easily transmitted from the driving unit such as the first gear unit 40 to the IC chip assembly 60. As a result, the contact state between the electrical contact surface 611 and the electrical connector 913 can be maintained better.

[0127] <4. Separation operation> After the developer cartridge 1 is installed, the drawer unit 90 can perform a so-called "separating operation" to temporarily separate the developer roller 30 from the photosensitive drum 92. As shown in FIG. 2, the first cover 45 of the developer cartridge 1 has a first columnar projection 46 extending in the third direction. Also, as shown in FIG. 3, the second cover 54 of the developer cartridge 1 has a second columnar projection 55 extending in the third direction. Meanwhile, as shown in FIG. 1, the drawer unit 9 has a plurality of pressing members 93. The pressing members 93 are provided on both sides of each cartridge holding portion 91 in the third direction.

[0128] 14, the first columnar projection 46 and the second columnar projection 55 are each pressed by the pressing member 93. This causes the casing 10 to be tilted in the first direction. As a result, the position of the holding surface 620 in the first direction relative to the casing 10 changes from the contact position described above to the final position.

[0129] 15 is a diagram showing a state when the separation operation is performed. During the separation operation, the positions of the first columnar projection 46 and the second columnar projection 55 change due to a driving force from the image forming apparatus. Specifically, the first columnar projection 46 and the second columnar projection 55 are each pressed by a lever (not shown) of the drawer unit 90. As a result, the first columnar projection 46 and the second columnar projection 55 each move against the pressing force of the pressing member 93. As a result, the casing 10 and the developing roller 30 of the developing cartridge 1 move in the second direction and away from the photosensitive drum 92, as indicated by the dashed arrow in FIG. 15.

[0130] At this time, the IC chip assembly 60 is fixed in a state sandwiched between the electric connector 913 and the second guide plate 912. Therefore, even though the casing 10 and the developing roller 30 move in the second direction, the position of the IC chip assembly 60 relative to the drawer unit 90 does not change. In addition, the state of the coil spring 73 also does not change and remains in the third state. Therefore, the position of the holder 62 in the second direction relative to the casing 10 changes from the standard position (first position) to the separated position (second position). In addition, the boss 621 moves in the second direction inside the through hole 451.

[0131] In this way, the developing cartridge 1 can change the position of the casing 10 in the second direction without changing the position of the electrical contact surface 611 relative to the drawer unit 90 in the second direction. Therefore, when performing the separation operation, the contact state between the electrical contact surface 611 and the electrical connector 913 can be maintained. Also, even when the image forming apparatus is transported with the developing cartridge 1 attached to the drawer unit 90, the contact state between the electrical contact surface 611 and the electrical connector 913 can be maintained, so that rubbing of the electrical contact surface 611 can be reduced.

[0132] <5. Modifications> Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. Various modified examples will be described below, focusing on the differences from the above embodiment.

[0133] <5-1. First modified example> FIG. 16 is a partially exploded perspective view of the developer cartridge 1A of the first modification. In the example of FIG. 16, as in the above embodiment, at least a part of the holder 62A that holds the IC chip 61A is covered by the first cover 45A. However, in the example of FIG. 16, the first cover 45A has bosses 451aA and 451bA. The bosses 451aA and 451bA are aligned in the second direction. The bosses 451aA and 451bA each extend in the third direction from the first cover 45A toward the casing 10A. Meanwhile, the holder 62A has one through hole 621A that penetrates in the third direction. Both the bosses 451aA and 451bA are inserted into the through hole 621A.

[0134] The size of the through hole 621A in the second direction is larger than the length between one end edge of the boss 451aA in the second direction and the other end edge of the boss 451bA in the second direction. That is, the size of the through hole 621A in the second direction is larger than the distance in the second direction between the parts of the bosses 451aA and 451bA that are farthest apart in the second direction. Therefore, the holder 62A can move in the second direction together with the through hole 621A relative to the casing 10A and the first cover 45A. When the holder 62A moves in the second direction, the IC chip 61A having the electrical contact surface 611A also moves in the second direction together with the holder 62A.

[0135] Furthermore, the size of the through hole 621A in the first direction is larger than the size of each of the bosses 451aA, 451bA in the first direction. Therefore, the holder 62A can move in the first direction together with the through hole 621A relative to the casing 10A and the first cover 45A. When the holder 62A moves in the first direction, the IC chip 61A having the electrical contact surface 611A also moves in the first direction together with the holder 62A. The holder 62A may also be movable in a third direction between the first cover 45A and the first outer surface 11A.

[0136] In this way, the first cover 45A is provided with the boss 451A, and the holder 62A is provided with the through hole 621A, so that the electrical contact surface 611A can move in the first and second directions relative to the casing 10A. Even with this structure, when the casing 10A is tilted in the first direction during installation of the developing cartridge 1A in the drawer unit, the boss 451A can move in the first direction inside the through hole 621A. Furthermore, when the developer cartridge 1A is installed and a separation operation is performed, the boss 451A can move in the second direction inside the through hole 621A. As a result, the position of the casing 10A can be changed while maintaining good contact between the electrical contact surface 611A and the electrical connector.

[0137] The number of bosses 451A provided on first cover 45A may be one or three or more. The number of through holes 621A provided on holder 62A may be two or more. Holder 62A may have a recess into which boss 451A is inserted instead of through hole 621A. A boss may be provided on the first outer surface of the casing, and the boss of the casing may be inserted into the through hole or recess of the holder. Boss 451A may be a cylinder or a rectangular column.

[0138] FIG. 17 is a cross-sectional view of the IC chip assembly 60A of FIG. 16 cut along a plane perpendicular to the third direction. As shown in FIG. 17, the holder 62A of this IC chip assembly 60A has a resin holder member 74A and a leaf spring 75A fixed to the holder member 74A. The holder member 74A has a first end 740A which is one end of the holder 62A in the first direction. The IC chip 61A is fixed to a holding surface 620A included in the outer surface of the first end 740A. The leaf spring 75A has a second end 750A which is the other end of the holder 62A in the first direction. In the holder 62A after assembly, the first end 740A and the second end 750A are separated in the first direction.

[0139] For example, a bent metal plate having flexibility is used for the leaf spring 75A. The leaf spring 75A expands and contracts in a first direction at least between a first state and a second state in which the leaf spring 75A is bent more than the first state. The length of the leaf spring 75A in the first state in the first direction is longer than the length of the leaf spring 75A in the first state in the first direction. Therefore, the distance in the first direction between the first end 740A and the second end 750A in the first state is longer than the distance in the first direction between the first end 740A and the second end 750A in the second state. Moreover, the length of the leaf spring 75A in the first direction at least in the second state is shorter than the natural length of the leaf spring 75A.

[0140] In this way, by using leaf spring 75A instead of a coil spring, IC chip assembly 60A may be expanded and contracted in the first direction. When developer cartridge 1A is attached to the drawer unit, the electrical contact surface 611A of IC chip 61A can be moved in the first direction relative to casing 10A by the dimensional difference between boss 451A and through hole 621A described above and the expansion and contraction of leaf spring 75A.

[0141] <5-2. Second modified example> FIG. 18 is a partial perspective view of the developing cartridge 1B of the second modified example. In the example of FIG. 18, the electrical contact surface 611B of the IC chip 61B faces the third direction. Therefore, the first direction perpendicular to the electrical contact surface 611B and the third direction are the same direction. In the example of FIG. 18, a columnar elastic body 63B is provided between the casing 10B and the IC chip assembly 60B. For example, a coil spring extending in the first direction is used for the columnar elastic body 63B. One end of the columnar elastic body 63B in the third direction is fixed to the holder 62B of the IC chip assembly 60B. The other end of the columnar elastic body 63B in the third direction is fixed to the first outer surface of the casing 10B. That is, the casing 10B and the IC chip assembly 60B are connected by the columnar elastic body 63B.

[0142] 19 and 20 are diagrams showing the movement of the IC chip assembly 60B due to the deformation of the columnar elastic body 63B. As shown in FIG. 19, the columnar elastic body 63B can expand and contract in a first direction. When the columnar elastic body 63B expands and contracts, the position of the electrical contact surface 611B relative to the casing 10B in the first direction also changes. Also, as shown in FIG. 20, the columnar elastic body 63B can deform obliquely with respect to the first direction. When the columnar elastic body 63B deforms obliquely, the relative position between one end and the other end of the columnar elastic body 63B changes in a direction perpendicular to the first direction.

[0143] 21 and 22 are diagrams showing a state in which the developing cartridge 1B of the second modification is attached to the drawer unit 90B. As shown in FIG. 21 and FIG. 22, the first cover 45B has a first frame portion 456B and a second frame portion 457B arranged at an interval in the second direction. The IC chip assembly 60B and the columnar elastic body 63B are housed in a storage portion 452B, which is a space between the first frame portion 456B and the second frame portion 457B. The first cover 45B also has a claw portion 453B protruding from the first frame portion 456B toward the storage portion 452B. Before the developing cartridge 1B is attached to the drawer unit 90B, as shown in FIG. 21, a part of the IC chip assembly 60 contacts the claw portion 453B. This maintains the columnar elastic body 63B in a state compressed in the first direction from its natural length.

[0144] When the developing cartridge 1B is attached to the drawer unit 90B, the electrical contact surface 611B of the IC chip 61B comes into contact with the electrical connector 913B as shown in Fig. 22. At this time, the length of the columnar elastic body 63B in the first direction becomes shorter than in the state shown in Fig. 21. Therefore, the repulsive force of the columnar elastic body 63B maintains the contact state between the electrical contact surface 611B and the electrical connector 913B.

[0145] FIG. 23 is a diagram showing a state in which a separating operation is performed after the developer cartridge 1B is mounted. During the separating operation, as shown in FIG. 23, the columnar elastic body 63B deforms obliquely with respect to the first direction. This causes the IC chip assembly 60B connected to one end of the columnar elastic body 63B and the casing 10B connected to the other end of the columnar elastic body 63B to move relatively in the second direction. Therefore, the position of the casing 10B in the second direction can be changed without changing the position of the electrical contact surface 611B with respect to the drawer unit 90B in the second direction. That is, the separating operation can be performed while maintaining the contact state between the electrical contact surface 611B and the electrical connector 913B.

[0146] <5-3.Third modified example> FIG. 24 is a perspective view of a developing cartridge 1C of a third modified example. In the example of FIG. 24, an IC chip assembly 60C has an IC chip 61C, a holder 62C, a shaft portion 66C, and a lever 67C. The shaft portion 66C extends in the second direction inside the first cover 45C. One end of the shaft portion 66C in the second direction is connected to the holder 62C in a manner that does not allow relative rotation. The other end of the shaft portion 66C in the second direction is connected to the lever 67C arranged outside the first cover 45C in a manner that does not allow relative rotation. Therefore, as shown by the dashed arrow in FIG. 24, when the lever 67C is rotated around the shaft portion 66C, the shaft portion 66C and the holder 62C also rotate around the shaft portion 66C. This changes the position of the holder 62C in the first direction.

[0147] 25 to 27 are views of the developing cartridge 1C of the third modified example seen from one side in the third direction. Before the developing cartridge 1C is attached to the drawer unit, as shown in FIGS. 24 and 25, the IC chip 61C and the holder 62C are housed inside the first cover 45C. When the developing cartridge 1C is attached to the drawer unit and the drawer unit is stored in the image forming apparatus, the lever 67C rotates around the shaft portion 66C. This causes a part of the holder 62C and the IC chip 61C to protrude from the first cover 45C. Then, as shown in FIG. 27, the electrical contact surface 611C of the IC chip 61C comes into contact with the electrical connector 913C provided on the drawer unit.

[0148] The lever 67C may be operated manually by the user after the developer cartridge 1C is attached to the drawer unit. Also, when the drawer unit is stored in the main body of the image forming apparatus, the lever 67C may be rotated by a guide surface provided in the main body of the image forming apparatus.

[0149] The first cover 45C has a support surface 454C that contacts the lever 67C before rotation. In the state of FIG. 25, one surface of the lever 67C in the second direction contacts the support surface 454C. As a result, the lever 67C, the shaft portion 66C, the holder 62C, and the IC chip 61C are supported in the second direction by the first cover 45C. However, as shown in FIG. 26, when the lever 67C is rotated, the lever 67C moves out of the support surface 454C. Therefore, one surface of the lever 67C in the second direction and the support surface 454C are not in contact with each other. Furthermore, the holder 62C is fixed to the position shown in FIG. 26 by a positioning member of the drawer unit. As a result, the electrical contact surface 611C of the IC chip 61C and the electrical connector 913C are maintained in contact with each other.

[0150] 26, one surface of the holder 62C in the second direction is also not in contact with the first cover 45C. Therefore, the lever 67C, the shaft portion 66C, the holder 62C, and the IC chip 61C can all be moved in the second direction relative to the first cover 45C. Therefore, during the separation operation of the developing cartridge 1C, as shown in FIG. 27, the casing 10C and the first cover 45C can be moved in the second direction while maintaining the contact state between the electrical contact surface 611C of the IC chip 61C and the electrical connector 913C.

[0151] <5-4. Fourth modified example> Fig. 28 is an exploded perspective view of the first cover 45D and the IC chip assembly 60D of the developing cartridge of the fourth modified example. Fig. 29 is a cross-sectional view of the first cover 45D and the IC chip assembly 60D. In the example of Figs. 28 and 29, the electrical contact surface 611D of the IC chip 61D faces the third direction. Therefore, the first direction perpendicular to the electrical contact surface 611D and the third direction are the same direction.

[0152] 28 and 29, an IC chip assembly 60D of a fourth modified example includes an IC chip 61D, a holder 62D that holds the IC chip 61D, and a joint member 63D. The holder 62D has a plurality of claws 622D that extend in the first direction toward the opposite side to the electrical contact surface 611D. In the example of FIG. 28, the holder 62D has four claws 622D. The joint member 63D includes a fixing portion 631D that is fixed to the first cover 45D, and an arm 632D that extends in the first direction from the fixing portion 631D toward the holder 62D.

[0153] A spherical portion 633D having a diameter larger than the thickness of the arm 632D is provided at the tip of the arm 632D in the first direction. The spherical portion 633D is held at a position inside the holder 62D by a plurality of claws 622D. As a result, as shown in FIG. 30, the arm 632D and the holder 62D are connected to each other so as to be rotatable relative to each other. That is, the IC chip 61D and the holder 62D are rotatable relative to each other around the spherical portion 633D. This allows the position of the electrical contact surface 611D of the IC chip 61D relative to the fixed portion 631D to be moved in the second direction. Therefore, during the separation operation of the developing cartridge, the casing and the first cover 45D can be moved in the second direction while maintaining the contact state between the electrical contact surface 611D of the IC chip 61D and the electrical connector.

[0154] 28 to 30, the claw portion 622D of the holder 62D and the arm 632D of the joint member 63D are relatively movable in the first direction. Therefore, when the developing cartridge is inserted into the drawer unit, the IC chip 61D and the holder 62D can be moved in the first direction relative to the fixing portion 631D. This allows the developing cartridge to be inserted while preventing the electrical contact surface 611D of the IC chip 61D from being rubbed.

[0155] An elastic member such as a coil spring that expands and contracts in the first direction may be interposed between the fixing portion 631D of the joint member 63D and the claw portion 622D. Also, an elastic member such as a coil spring that expands and contracts in the first direction may be interposed between the first cover 45D and the claw portion 622D. In this case, the repulsive force of the elastic member can bring the electrical contact surface 611D into better contact with the electrical connector.

[0156] Also, the arm 632D may be rotatably connected to the fixed portion 631D or the first cover 45D. For example, a spherical portion may be provided at both ends of the arm 632D, and one of the spherical portions may be rotatably held by a plurality of claws provided on the first cover 45D. By rotatably connecting both ends of the arm 632D in this manner, the position of the electrical contact surface 611D in the second direction can be changed more flexibly.

[0157] <5-5. Fifth Variation> FIG. 31 is a partial perspective view of a developing cartridge 1E of a fifth modified example. In the example of FIG. 31, a holder 62E for holding an IC chip 61E is made of a plate-like member that extends in an annular shape and has its ends connected to each other. The material of the holder 62E is, for example, a flexible resin. Therefore, in the example of FIG. 31, the holder 62E itself is an elastic body that can expand and contract in the first direction. In this way, the distance between both ends of the holder 62E in the first direction can be changed. Therefore, when the developing cartridge 1E is inserted into the drawer unit, it is possible to prevent the electrical contact surface 611E of the IC chip 61E from being rubbed.

[0158] 31, it is not necessary to configure holder 62E with a plurality of members in order for holder 62E to expand and contract in the first direction, nor is it necessary to use an elastic member in holder 62E in addition to the member that holds IC chip 61E.

[0159] Fig. 32 is an exploded perspective view of a first cover 45E and an IC chip assembly 60E of a fifth modified example. As shown in Fig. 32, the first cover 45E has a boss 451aE extending in a first direction and a boss 451bE extending in the first direction. The bosses 451aE and 451bE are arranged in a second direction. The first cover 45E further has a connecting portion 455E connecting the tips of the bosses 451aE and 451bE.

[0160] The holder 62E extends in an annular shape around the boss 451aE and the boss 451bE. The claws 623E provided at both ends of the holder 62E mesh with each other. As a result, a through hole 621E penetrating in the first direction is formed inside the holder 62E. The boss 451aE and the boss 451bE are located inside the through hole 621E. The holder 62E further has a plate-shaped portion 624E protruding from its inner circumferential surface toward the through hole 621E. The plate-shaped portion 624E is inserted between the boss 451aE and the boss 451bE.

[0161] The distance between bosses 451aE and 451bE in the second direction is greater than the thickness of plate-shaped portion 624E in the second direction. Therefore, holder 62E can move in the second direction relative to casing 10E and first cover 45E together with plate-shaped portion 624E. When holder 62E moves in the second direction, IC chip 61E having electrical contact surface 611E also moves in the second direction together with holder 62E.

[0162] Furthermore, the size of the through hole 621E in the first direction is larger than the size of each of the bosses 451aE, 451bE in the first direction. Therefore, the holder 62E can move in the first direction relative to the casing 10E and the first cover 45E. When the holder 62E moves in the first direction, the IC chip 61E having the electrical contact surface 611E also moves in the first direction together with the holder 62E.

[0163] When the developer cartridge 1E is attached to the drawer unit, the holder 62E is compressed in the first direction by being sandwiched between the guide plates of the drawer unit. Specifically, the claws 623E provided at both ends of the holder 62E approach each other, and a biasing force is generated in a direction in which the claws 623E move away from each other. Then, with the holder 62E in an elastically deformed state, the electrical contact surface 611E of the IC chip 61E comes into contact with the electrical connector. The biasing force fixes the electrical contact surface 611E and the electrical connector in a state of contact with each other. During a separation operation, the casing 10E moves in the second direction while the electrical contact surface 611E and the electrical connector are kept in contact with each other.

[0164] Even with this structure, when the casing 10E is tilted in the first direction during installation of the developer cartridge 1E in the drawer unit, the bosses 451aE, 451bE can be moved in the first direction inside the through hole 621E. Furthermore, when a separating operation is performed after installation of the developer cartridge 1E, the bosses 451aE, 451bE can be moved in the second direction inside the through hole 621E. As a result, the position of the casing 10E can be changed while maintaining good contact between the electrical contact surface 611E and the electrical connector.

[0165] The number of bosses provided on the first cover 45E may be one, or may be three or more.

[0166] <5-6. Sixth Variation> FIG. 33 is a perspective view of a developing cartridge 1F and a drum cartridge 80F of a sixth modified example. The developing cartridge 1F of FIG. 33 includes a casing 10F, a developing roller 30F, an IC chip assembly 60F, and a first cover 45F. In the example of FIG. 33, the developing cartridge 1F is mounted to a drum cartridge 80F, not to a drawer unit. The drum cartridge 80F has one developing cartridge holder 81F that holds one developing cartridge 1F. The developing cartridge holder 81F is provided with a photosensitive drum 82F. When the developing cartridge 1F is mounted to the drum cartridge 80F, the developing roller 30F of the developing cartridge 1F comes into contact with the photosensitive drum 82F.

[0167] Fig. 34 is a diagram showing how the drum cartridge 80F with the developing cartridge 1F mounted thereon is mounted to the image forming apparatus 100F. As shown in Fig. 34, the drum cartridge 80F with the developing cartridge 1F mounted thereon is mounted to a drum cartridge holding portion 101F provided in the image forming apparatus 100F.

[0168] In this way, a structure equivalent to the IC chip assemblies of the above embodiment or the first to fifth modified examples can be adopted for a developing cartridge 1F of the type that is mounted in a drum cartridge 80F. FIG. 35 is an exploded perspective view of the vicinity of an IC chip assembly 60F of a developing cartridge 1F. As shown in FIG. 35, the IC chip assembly 60F of the developing cartridge 1F has an IC chip 61F, which is a storage medium, and a holder 62F that holds the IC chip 61F. The holder 62F is held by a first cover 45F at a side portion in the third direction of the casing 10F.

[0169] The holder 62F has a first holder member 71F, a second holder member 72F, and a coil spring 73F. The coil spring 73F is an elastic member that expands and contracts in a first direction.

[0170] The first holder member 71F has a boss 621aF, a boss 621bF, and a boss 621cF. The boss 621aF extends in the third direction from a surface of the first holder member 71F facing the first cover 45F toward the first cover 45F. Meanwhile, the first cover 45F has a through hole 451F. The through hole 451F penetrates the first cover 45F in the third direction. The boss 621aF is inserted into the through hole 451aF.

[0171] The boss 621bF and the boss 621cF each extend in the third direction from the surface of the first holder member 71 facing the casing 10F toward the casing 10F. Meanwhile, the casing 10F has a recess 15aF and a recess 15bF. The recess 15aF and the recess 15bF each recess in the third direction in the first outer surface 11F of the casing 10F. The boss 621bF is inserted into the recess 15aF. The boss 621cF is inserted into the recess 15bF.

[0172] The size (inner dimension) of the through hole 451F in the second direction is larger than the size (outer dimension) of the boss 621aF in the second direction. The size (inner dimension) of the recess 15aF in the second direction is larger than the size (outer dimension) of the boss 621bF in the second direction. Also, the size (inner dimension) of the recess 15bF in the second direction is larger than the size (outer dimension) of the boss 621cF in the second direction. Therefore, the holder 62F can move in the second direction relative to the casing 10F and the first cover 45F together with the boss 621aF, the boss 621bF, and the boss 621cF. When the holder 62F moves in the second direction, the IC chip 61F having the electrical contact surface 611F also moves in the second direction together with the holder 62F.

[0173] The size (inner dimension) of the through hole 451F in the first direction is larger than the size (outer dimension) of the boss 621aF in the first direction. The size (inner dimension) of the recess 15aF in the first direction is larger than the size (outer dimension) of the boss 621bF in the first direction. Also, the size (inner dimension) of the recess 15bF in the first direction is larger than the size (outer dimension) of the boss 621cF in the first direction. Therefore, the holder 62F can move in the first direction relative to the casing 10F and the first cover 45F together with the boss 621aF, the boss 621bF, and the boss 621cF. When the holder 62F moves in the first direction, the IC chip 61F having the electrical contact surface 611F also moves in the first direction together with the holder 62F.

[0174] 34, the second holder member 72 has a recess 625F. Meanwhile, the drum cartridge 80F has a protrusion 83F. The recess 625F and the protrusion 83F face each other in the first direction. The size of the recess 625F gradually increases as it moves away from the IC chip 61F in the first direction. Also, the size of the protrusion 83F gradually decreases as it moves toward the tip in the first direction.

[0175] As shown in FIG. 34, the image forming apparatus 100F has an electric connector 102F. When the drum cartridge 80F with the developing cartridge 1F attached is inserted into the image forming apparatus 100F, the first holder member 71F comes into contact with the member of the image forming apparatus 100F. Also, the protrusion 83F of the drum cartridge 80F fits into the recess 625F of the second holder member 72F. This fixes the position of the second holder member 72F relative to the drum cartridge 80F. As a result, the holder 62F is sandwiched between the member of the image forming apparatus 100F and the drum cartridge 80, so that the coil spring 73F is compressed in the first direction. Also, when the drum cartridge F is further inserted into the image forming apparatus 100F, the electrical contact surface 611F of the IC chip 61F comes into contact with the electric connector 102F.

[0176] The IC chip 61F contacts the electrical connector 102F while receiving the repulsive force of the coil spring 73F. The holder 62F is sandwiched between the electrical connector 102F and the protrusion 83F. This positions the holder 62F relative to the image forming apparatus 100F and the drum cartridge 80F.

[0177] As shown in FIG. 35, the second holder member 72F has a claw portion 714F. The claw portion 714F protrudes from the second holder member 72F in a direction intersecting the first direction. In the example of FIG. 35, the claw portion 714F protrudes from the second holder member 72F in a third direction. Meanwhile, the first holder member 71F has an opening 721F. The claw portion 714F is inserted into the opening 721F. This prevents the first holder member 71F from being removed from the second holder 72F.

[0178] Also, the casing 10F of the developing cartridge 1F has a first rib 46F and a second rib 55F. The first rib 46F protrudes in the third direction from the first outer surface 11F. The second rib 55F protrudes in the third direction from the second outer surface 12F. Meanwhile, the drum cartridge 80F has a first lever 84F and a second lever 85F. During the separation operation, the first lever 84F and the second lever 85F are operated by a driving force from the image forming apparatus. Then, the first rib 46F is pushed by the first lever 84F. Also, the second rib 55F is pushed by the second lever 85F. This causes the positions of the first rib 46F and the second rib 55F to change. As a result, the casing 10 and the developing roller 30 of the developing cartridge 1 move in the second direction and move away from the photosensitive drum 92.

[0179] As described above, the developing cartridge 1F can also change the position of the holder 62F in the second direction relative to the casing 10F. Therefore, the position of the casing 10F in the second direction can be changed without changing the position of the electrical contact surface 611F in the second direction relative to the electrical connector 102F. Therefore, the electrical contact surface 611F and the electrical connector 102F can be separated while maintaining their contact state. As a result, rubbing of the electrical contact surface 611F can be reduced.

[0180] Also, in this developing cartridge 1F, the electrical contact surface 611F is capable of moving in the first direction relative to the casing 10F. Therefore, when the drum cartridge 80F is mounted in the image forming apparatus 100F, rubbing of the electrical contact surface 611F can be suppressed.

[0181] <5-7. Other variations> In the above embodiment, the IC chip having the electrical contact surface is fixed to the outer surface of the holder. However, only the electrical contact surface that contacts the electrical connector may be fixed to the outer surface of the holder, and the portion of the IC chip other than the electrical contact surface may be disposed in another location of the developer cartridge.

[0182] In the above embodiment, the gears in the first gear section and the second gear section are engaged with each other by meshing of gear teeth. However, the gears in the first gear section and the second gear section may be engaged with each other by frictional force. For example, a friction member (e.g., rubber) may be provided on the outer periphery of the two gears that engage with each other instead of the gear teeth.

[0183] Furthermore, the developing cartridge 1 in the above embodiment is mounted to a drawer unit of an image forming apparatus. However, the developing cartridge of the present invention may be mounted to a main body of an image forming apparatus that does not have a drawer unit.

[0184] In addition, the detailed shape of the developing cartridge may be different from the shape shown in each drawing of the present application. Furthermore, the elements appearing in the above-mentioned embodiment and modified examples may be appropriately combined within a range where no contradiction occurs. [Explanation of symbols]

[0185] 1,1A,1B,1C,1E,1F Developer cartridge 10, 10A, 10B, 10C, 10E, 10F Casing 11 First outer surface 12 Second outer surface 13 Developer Room 14 Openings 20 Agitator 21 Agitator shaft 22 Stirring blade 30,30F Developing roller 31 Roller body 32 Roller shaft 40 First Gear Section 41 Coupling 42 Development Gear 43 Idle Gear 44 First agitator gear 45, 45A, 45B, 45C, 45D, 45E, 45F First cover 50 Second Gear Section 51 Second agitator gear 52 Detection Gear 53 Conductive materials 54 2nd Cover 60,60A,60B,60C,60D,60E,60F IC chip assembly 61, 61A, 61B, 61C, 61D, 61E, 61F IC chip 62,62A,62B,62C,62D,62E,62F Holder 63B Columnar elastic body 63D Joint material 66C Shaft section 67C Lever 71, 71F First holder member 72, 72F Second holder member 73,73F Coil spring 74A Holder parts 75A Leaf Spring 80F Drum Cartridge 81F Developing cartridge holder 82F Photosensitive drum 90,90B Drawer unit 91 Cartridge holder 92 Photosensitive drum 100F Image forming device 101F Drum cartridge holder 102F Electrical Connector 451,451F Through hole 451aA, 451bA, 451aE, 451bE Boss 611,611A,611B,611C,611D,611E,611F Electrical contact surface 620,620A holding surface 621,621F Boss 621A,621E Through hole 631D Fixed part 632D Arm 633D Spherical part 710,740A 1st end 711 First guide surface 712 Second guide surface 713a, 713b Third guide surface 720,750A 2nd end 910 Insertion port 911 First guide plate 912 Second guide plate 913,913B,913C Electrical Connectors 914 Guide protrusion

Claims

1. A housing that contains a developer therein; a storage medium having an electrical contact surface; an elastic member extending in a first direction intersecting the electrical contact surface, the elastic member being stretchable in the first direction between a first state and a second state; a developing roller located on one side of the housing in the second direction, the developing roller being rotatable about an axis extending in a third direction different from the first direction and the second direction; a holder that holds the electrical contact surface, the holder being movable in the first direction between a first position and a second position relative to the housing; Equipped with a length of the elastic member in the first direction in the first state is longer than a length of the elastic member in the second state,

2. 2. The developing cartridge according to claim 1, The developing cartridge, wherein the first direction is a direction perpendicular to the electrical contact surface.

3. 3. The developing cartridge according to claim 1, The developing cartridge, wherein the holder is movable together with the storage medium.

4. 4. The developing cartridge according to claim 1, The developing cartridge, wherein the holder holds the storage medium.

5. 5. The developing cartridge according to claim 1, The developing cartridge, wherein the holder is located on a side of the housing.

6. 6. The developing cartridge according to claim 1, The developing cartridge, wherein the elastic member is a spring.

7. 7. The developing cartridge according to claim 6, The developing cartridge, wherein the spring is a coil spring.

Images