Image forming device

Abstract

To provide an image forming apparatus using a developing cartridge having an electrical contact surface, and reduce rubbing on the electrical contact surface.SOLUTION: The present image forming apparatus comprises: a photoconductor drum 92 that can rotate about a first shaft extending in a first direction; a developing cartridge 1; and a frame to which the developing cartridge 1 can be attached. The developing cartridge 1 includes a housing that can store a developer, a developing roller 30, a storage medium that has an electrical contact surface 611, and a holder 62 that holds the electrical contact surface 611. The frame includes an electrical contact that is in contact with the electrical contact surface 611 of the developing cartridge 1. The image forming apparatus can move the housing with respect to the holder 62 while maintaining a contact state of the electrical contact surface 611 with the electrical contact. Thus, rubbing on the electrical contact surface 611 can be reduced.SELECTED DRAWING: Figure 16

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus. [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. Conventional image forming devices are described, for example, in Patent Documents 1 and 2. The image forming device in Patent Document 1 has a drawer unit. The drawer unit has a photosensitive drum. The developing cartridge is attached to the drawer unit. When the developing cartridge is attached to the drawer unit, the photosensitive drum and the developing roller come into contact with each other.

[0003] The developer cartridge of Patent Document 2 is mounted to a drum cartridge. The drum cartridge has a photosensitive drum. When the developer cartridge is mounted to the drum cartridge, the photosensitive drum and the developing roller come into contact with each other. Then, the drum cartridge with the developer cartridge mounted thereto is mounted to an image forming apparatus.

[0004] The image forming apparatus performs a separation operation as needed. During the separation operation, the developing roller is temporarily separated from the photosensitive drum. For example, in a color printer, when performing monochrome printing, the developing rollers of the developer cartridges other than the black one are separated from the photosensitive drum. At this time, the position of the housing of the developer cartridge relative to the drawer unit or the drum cartridge changes. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-59510 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-54058 Summary of the Invention [Problem to be solved by the invention]

[0006] Conventionally, a developer cartridge having a storage medium is known. The storage medium is, for example, an IC chip. The storage medium has an electrical contact surface. The electrical contact surface of the storage medium contacts a terminal portion provided on the image forming apparatus or the drawer unit. Conventionally, a developer cartridge having an electrode is also known. The electrode receives power from the image forming apparatus. The electrode also has an electrical contact surface. The electrical contact surface of the electrode contacts a terminal portion provided on the image forming apparatus or the drawer unit.

[0007] However, when an image forming apparatus separates a developer cartridge having an electrical contact surface, the relative positional relationship between the electrical contact surface and the terminal portion changes as the position of the housing changes, resulting in friction between the electrical contact surface and the terminal portion each time the separation operation is performed.

[0008] SUMMARY OF THE INVENTION An object of the present invention is to reduce abrasion of an electrical contact surface in an image forming apparatus using a developer cartridge having an electrical contact surface. [Means for solving the problem]

[0009] In order to solve the above problem, the first invention of the present application is an image forming device comprising: a photosensitive drum rotatable about a first axis extending in a first direction; a developing cartridge having a housing capable of containing developer, a developing roller rotatable about a second axis extending in the first direction, a storage medium having an electrical contact surface, and a holder located on one side of the housing in the first direction, extending in a second direction intersecting the electrical contact surface, and holding the electrical contact surface on a first outer surface located on one side of the second direction; and a frame to which the developing cartridge can be attached, the frame having electrical contacts that contact the electrical contact surface of the developing cartridge attached to the frame, wherein the housing is movable relative to the holder in a direction away from the photosensitive drum so that the developing roller moves away from the photosensitive drum when the electrical contact surface and the electrical contact are in contact.

[0010] The second invention of the present application is an image forming apparatus of the first invention, wherein the holder further comprises a second outer surface located on the other side of the second direction and movable in the second direction relative to the first outer surface, and an elastic member located between the first outer surface and the second outer surface and expandable in the second direction, and wherein the electrical contact surface comes into contact with the electrical contact due to the elastic force of the elastic member.

[0011] The third invention of the present application is an image forming apparatus of the second invention, characterized in that the frame has a first guide plate having the electrical contact and a second guide plate contacting the second outer surface, and the length in the second direction between the electrical contact and the second guide plate is shorter than the length in the second direction between the electrical contact surface and the second outer surface in the developing cartridge before installation.

[0012] The fourth invention of the present application is an image forming apparatus of the third invention, characterized in that when the developing cartridge is inserted into the frame, the second outer surface moves along the second guide plate, thereby bringing the second outer surface closer to the first outer surface and shortening the length of the elastic member in the second direction.

[0013] The fifth invention of the present application is an image forming apparatus according to the third or fourth invention, characterized in that the housing is movable in the separating direction relative to the holder while the second outer surface is in contact with the second guide plate and the electrical contact surface is in contact with the electrical contact.

[0014] A sixth aspect of the present invention is the image forming apparatus of any one of the first to fifth aspects, further comprising a pressing member that presses the housing in the separating direction.

[0015] The seventh invention of the present application is an image forming apparatus according to the sixth invention, characterized in that the pressure of the pressing member causes the developing roller and the photosensitive drum to change from a contact state in which they are in contact with each other to a separated state in which they are separated from each other, and in both the contact state and the separated state, the electrical contact surface and the electrical contact are in contact.

[0016] The eighth invention of the present application is an image forming apparatus according to any one of the first to seventh inventions, characterized in that the developing cartridge further has a holder cover that holds the holder between the developing cartridge and the housing, and the holder cover is fixed to the housing, and the housing and the holder cover are movable in the separating direction relative to the holder while the electrical contact surface and the electrical contact are in contact.

[0017] A ninth aspect of the present invention is an image forming apparatus according to any one of the first to eighth aspects, characterized in that the storage medium is an IC chip having the electrical contact surface.

[0018] A tenth aspect of the present invention is the image forming apparatus of any one of the first to ninth aspects, characterized in that the frame includes the photosensitive drum.

[0019] The 11th invention of the present application is an image forming apparatus according to the 10th invention, characterized in that the frame has a plurality of slots into which the developing cartridges can be attached, and each slot is provided with a photosensitive drum.

[0020] The 12th invention of the present application is an image forming apparatus comprising a developing cartridge having a housing capable of containing developer, a developing roller rotatable about an axis extending in a first direction, a storage medium having an electrical contact surface, and a holder located on one side of the housing in the first direction, extending in a second direction intersecting the electrical contact surface, and holding the electrical contact surface on a first outer surface located on one side of the second direction; and a frame into which the developing cartridge can be inserted in an insertion direction, wherein the frame has electrical contacts that contact the electrical contact surface of the developing cartridge attached to the frame, and the housing is movable in the insertion direction relative to the holder while the electrical contact surface and the electrical contact are in contact.

[0021] The 13th invention of the present application is an image forming apparatus comprising a developing cartridge having a housing capable of containing developer, a developing roller, an electrical contact surface, and a holder that holds the electrical contact surface, and a frame to which the developing cartridge can be attached, wherein the frame has electrical contacts that contact the electrical contact surface of the developing cartridge attached to the frame, and when the electrical contact surface and the electrical contact are in contact, the housing can move relative to the holder in a direction that intersects the direction in which the electrical contact surface and the electrical contact face each other. [Effects of the Invention]

[0022] According to the first to thirteenth aspects of the present invention, the housing can be moved relative to the holder while maintaining contact between the electrical contact surfaces and the electrical contacts, thereby reducing friction on the electrical contact surfaces.

[0023] Furthermore, according to the second aspect of the present invention, the elastic member can be used to maintain contact between the electrical contact surface and the electrical contact.

[0024] According to the third aspect of the present invention, the elastic member can be compressed in the second direction beyond its natural length to generate a repulsive force in the elastic member, thereby maintaining contact between the electrical contact surface and the electrical contact.

[0025] Furthermore, according to the fifth aspect of the present invention, the holder can be fixed between the first guide plate and the second guide plate, and the housing can be smoothly moved in the direction away from the holder.

[0026] Furthermore, according to the eighth aspect of the present invention, the housing and the holder cover can be moved smoothly relative to the holder. [Brief explanation of the drawings]

[0027] [Figure 1] FIG. 1 is a conceptual diagram of an image forming apparatus. [Figure 2] FIG. 2 is a perspective view of the drawer unit and the developing cartridge. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] FIG. 2 is an exploded perspective view of an IC chip assembly. [Figure 6] FIG. 2 is a cross-sectional view of an IC chip assembly. [Figure 7] FIG. [Figure 8] FIG. 3 is a cross-sectional view of a first guide plate and a second guide plate. [Figure 9] FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. [Figure 10] FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. [Figure 11] FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. [Figure 12] FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. [Figure 13] FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. [Figure 14] FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. [Figure 15] FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. [Figure 16] FIG. 10 is a diagram showing a state when a separating operation is performed. DETAILED DESCRIPTION OF THE INVENTION

[0028] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[0029] <1. Configuration of image forming device> FIG. 1 is a conceptual diagram of an image forming apparatus 100. This image forming apparatus 100 is an electrophotographic printer. Examples of the image forming apparatus 100 include a laser printer and an LED printer. The image forming apparatus 100 includes four developer cartridges 1 and a drawer unit 90. The drawer unit 90 is a frame into which the four developer cartridges 1 can be attached. The image forming apparatus 100 forms an image on the recording surface of printing paper using developer (for example, toner) supplied from the four developer cartridges 1.

[0030] FIG. 2 is a perspective view of the drawer unit 90 and the developer cartridges 1. As shown in FIGS. 1 and 2, the four developer cartridges 1 can be individually replaced with respect to the drawer unit 90. When replacing the developer cartridges 1, the drawer unit 90 is pulled out from the front of the image forming apparatus 100. The developer cartridges 1 are removed and installed into four slots 91 provided in the drawer unit 90. The drawer unit 90 includes four photosensitive drums 92. The photosensitive drums 92 are located near the bottom of each of the four slots 91. The photosensitive drums 92 are rotatable about a horizontally extending rotation axis (first axis). Hereinafter, the direction in which the rotation axis of the photosensitive drums 92 extends is referred to as the "first direction."

[0031] 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.

[0032] As shown in FIGS. 1 and 2, each of the four developer cartridges 1 has an IC chip 61. The IC chip 61 is a storage medium from which information can be read and written. The image forming apparatus 100 also has a control unit 80. When the four developer cartridges 1 are attached to the drawer unit 90, the IC chip 61 of each developer cartridge 1 is electrically connected to the control unit 80. The control unit 80 is formed, for example, by a circuit board. The control unit 80 has a processor such as a CPU and various memories. The control unit 80 executes various processes in the image forming apparatus 100 by causing the processor to operate in accordance with a program.

[0033] <2. Overall structure of the developing cartridge> 3 and 4 are perspective views of the developer cartridge 1. As shown in FIGS. 3 and 4, the developer cartridge 1 of this embodiment has a casing 10, an agitator 20, a development roller 30, a first gear portion 40, a second gear portion 50, and an IC chip assembly 60.

[0034] The casing 10 is a housing capable of containing a developer. The casing 10 extends in a first direction between a first end surface 11 and a second end surface 12. The first gear portion 40 and the IC chip assembly 60 are located at the first end surface 11. The second gear portion 50 is located at the second end surface 12. A storage chamber 13 is provided inside the casing 10. The developer is stored in the storage chamber 13. The casing 10 has an opening 14. The opening 14 is located at an end of the casing 10 in the insertion direction of the developer cartridge 1 into the drawer unit 90. The storage chamber 13 communicates with the outside via the opening 14.

[0035] The agitator 20 has an agitator shaft 21 and an agitator blade 22. The agitator shaft 21 extends along a first direction. The agitator blade 22 extends radially outward from the agitator shaft 21. At least a portion of the agitator shaft 21 and the agitator blade 22 are disposed inside the storage chamber 13. 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 first direction. Therefore, the agitator shaft 21 and the agitator blade 22 rotate together with the first agitator gear 44 and the second agitator gear 51. When the agitator blade 22 rotates, the developer in the storage chamber 13 is agitated.

[0036] The developing roller 30 is a roller that can rotate about a rotation axis (second axis) that extends in a first direction. The developing roller 30 is disposed in the opening 14 of the casing 10. The developing roller 30 of this embodiment has a developing roller main body 31 and a developing roller shaft 32. The developing roller main body 31 is a cylindrical member that extends in the first direction. The developing roller main body 31 is made of a material such as elastic rubber. The developing roller shaft 32 is a cylindrical member that penetrates the developing roller main body 31 in the first direction. The developing roller shaft 32 is made of a material such as metal or a conductive resin. The developing roller main body 31 is fixed to the developing roller shaft 32 so as not to rotate relative to it.

[0037] One end of the developing roller shaft 32 in the first direction is fixed to the developing roller gear 42, which will be described later, so as not to rotate relative to the developing roller gear 42. Therefore, when the developing roller gear 42 rotates, the developing roller shaft 32 also rotates, and the developing roller main body 31 rotates together with the developing roller shaft 32.

[0038] The developing roller shaft 32 does not have to penetrate the developing roller main body 31 in the first direction. For example, a pair of developing roller shafts 32 may extend in the first direction from both ends of the developing roller main body 31 in the first direction.

[0039] The developer cartridge 1 also has a supply roller (not shown). The supply roller is located between the developing roller 30 and the storage chamber 13. The supply roller is rotatable about a rotation axis extending in the first direction. When the developer cartridge 1 receives a driving force, developer is supplied from the storage chamber 13 in the casing 10 to the outer circumferential surface of the developing roller 30 via the supply roller. 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 developing roller shaft 32 of the developing roller 30. Therefore, the developer is attracted to the outer circumferential surface of the developing roller main body 31 due to the electrostatic force between the developing roller shaft 32 and the developer.

[0040] The developing cartridge 1 also has a layer thickness regulating blade (not shown). The layer thickness regulating blade shapes the developer supplied to the outer circumferential surface of the developing roller main body 31 to a uniform thickness. The developer on the outer circumferential surface of the developing roller main body 31 is then supplied to a photosensitive drum 92 provided in a drawer unit 90. At this time, the developer moves from the developing roller main body 31 to the photosensitive drum 92 in accordance with the electrostatic latent image formed on the outer circumferential surface of the photosensitive drum 92. As a result, the electrostatic latent image is visualized on the outer circumferential surface of the photosensitive drum 92.

[0041] The first gear portion 40 is located on the first end surface 11 of the casing 10. Figure 3 is a perspective view of the developer cartridge 1 with the first gear portion 40 disassembled. As shown in Figure 3, the first gear portion 40 has a coupling 41, a developing roller gear 42, an idle gear 43, a first agitator gear 44, and a first cover 45. Note that in Figure 3, the multiple gear teeth of each gear are not shown.

[0042] The coupling 41 is a gear that first receives the driving force supplied from the image forming apparatus 100. The coupling 41 is capable of rotating about a rotation axis that extends in a first direction. The coupling 41 has a coupling portion 411 and a coupling gear 412. The coupling portion 411 and the coupling gear 412 are integrally formed from, for example, resin. The coupling portion 411 is provided with a fastening hole 413 that is recessed in the first direction. Furthermore, the outer periphery of the coupling gear 412 is provided with a plurality of gear teeth that are equally spaced around the entire circumference.

[0043] When the drawer unit 90 with the developer cartridge 1 attached is stored in the image forming apparatus 100, the drive shaft of the image forming apparatus 100 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.

[0044] The developing roller gear 42 is a gear for rotating the developing roller 30. The developing roller gear 42 is rotatable about a rotation axis extending in the first direction. A plurality of gear teeth are provided at equal intervals around the outer periphery of the developing roller gear 42. Some of the gear teeth of the coupling gear 412 and some of the gear teeth of the developing roller gear 42 mesh with each other. The developing roller gear 42 is fixed to the end of the developing roller shaft 32 in the first direction so as not to rotate relative to the developing roller gear 42. Therefore, when the coupling gear 412 rotates, the developing roller gear 42 rotates, and the developing roller 30 rotates together with the developing roller gear 42.

[0045] 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 rotatable about a rotation axis extending in the first direction. The idle gear 43 has a large diameter gear portion 431 and a small diameter gear portion 432 arranged in the first direction. The small diameter gear portion 432 is located between the large diameter gear portion 431 and the first end face 11 of the casing 10. In other words, the large diameter gear portion 431 is farther from the first end face 11 than the small diameter gear portion 432. 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 integrally formed from, for example, resin.

[0046] The large diameter gear portion 431 and the small diameter gear portion 432 each have a plurality of gear teeth provided at equal intervals around the entire circumference on their outer peripheries. The number of gear teeth on the small diameter gear portion 432 is smaller than the number of gear teeth on the large diameter gear portion 431. Some of the gear teeth on the coupling gear 412 and some of the gear teeth on the large diameter gear portion 431 mesh with each other. Some of the gear teeth on the small diameter gear portion 432 and some of the gear teeth on 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. Then, as the small diameter gear portion 432 rotates, the first agitator gear 44 also rotates.

[0047] The first agitator gear 44 is a gear for rotating the agitator 20 in the accommodation chamber 13. The first agitator gear 44 is rotatable about a rotation axis extending in the first direction. A plurality of gear teeth are provided at equal intervals around the outer periphery of the first agitator gear 44. As described above, some of the gear teeth of the small diameter gear portion 432 and 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 first direction so as not to rotate relative to the agitator gear 44. 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.

[0048] The first cover 45 is fixed to the first end surface 11 of the casing 10, for example, by screws. The coupling gear 412, the developing roller gear 42, the idle gear 43, and the first agitator gear 44 are housed between the first end surface 11 and the first cover 45. The fastening hole 413 of the coupling part 411 is exposed to the outside of the first cover 45. The first cover 45 also has a first columnar protrusion 46 extending in the first direction. 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.

[0049] The second gear portion 50 is located on the second end surface 12 of the casing 10. FIG. 4 is a perspective view of the developer cartridge 1 with the second gear portion 50 disassembled. As shown in FIG. 4, 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. 4, the multiple gear teeth of the second agitator gear 51 are not shown.

[0050] 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 is rotatable about a rotation axis extending in the first direction. A plurality of gear teeth are provided at equal intervals around the outer periphery of the second agitator gear 51. When the developer cartridge 1 is new (unused), some of the gear teeth of the second agitator gear 51 can mesh with some of the gear teeth of the detection gear 52. The second agitator gear 51 is fixed to the other end of the agitator shaft 21 in the first direction so as not to rotate relative to the agitator shaft 21. Therefore, when the agitator shaft 21 rotates, the second agitator gear 51 also rotates.

[0051] The detection gear 52 is a gear for transmitting information about the developer cartridge 1 to the image forming apparatus 100. The information about the developer cartridge 1 includes 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 specifications of the developer cartridge 1. The specifications of the developer cartridge 1 include, for example, the amount of developer in the developer cartridge 1 or yield information that indicates the number of pages that can be printed using the developer.

[0052] The detection gear 52 is rotatable about a rotation axis extending in the first direction. The detection gear 52 has multiple gear teeth on a portion of its outer periphery. When a new developer cartridge 1 is attached to the drawer unit 90 and the drawer unit 90 is housed in the image forming apparatus 100, the coupling 41 receives a driving force from the image forming apparatus 100. The second agitator gear 51 rotates due to the driving force transmitted from the coupling 41 via the idle gear 43, the first agitator gear 44, and the agitator 20. The detection gear 52 rotates by meshing with the second agitator gear 51. However, the detection gear 52 has gear teeth only on a portion of its outer periphery. Therefore, when the detection gear 52 rotates a predetermined angle, the second agitator gear 51 and the detection gear 52 disengage from each other, and the rotation of the detection gear 52 stops.

[0053] In this way, in a developer cartridge 1 that has been used once in the image forming apparatus 100, the meshing between the second agitator gear 51 and the detection gear 52 is disengaged. Therefore, when a developer cartridge 1 that has been used once is removed from the image forming apparatus 100 and then re-installed in the image forming apparatus 100, the rotation of the second agitator gear 51 is not transmitted to the detection gear 52. Therefore, the detection gear 52 does not rotate.

[0054] 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.

[0055] 4, the detection gear 52 has a detection protrusion 521. The detection protrusion 521 protrudes in a first direction. The detection protrusion 521 extends in an arc shape centered on the rotation axis of the detection gear 52. When the detection gear 52 rotates, the detection protrusion 521 also rotates. That is, the position of the detection protrusion 521 changes as the detection gear 52 rotates.

[0056] The conductive member 53 is an electrically conductive member. The conductive member 53 is made of a conductive metal or a conductive resin. The conductive member 53 is located on the second end surface 12 of the casing 10. The conductive member 53 has a cylindrical gear shaft 531 protruding in the first direction. The detection gear 52 is supported by the gear shaft 531 and rotates around the gear shaft 531. The detection protrusion 521 partially covers the periphery of the gear shaft 531. The conductive member 53 also has a bearing portion 532. The bearing portion 532 contacts the developing roller shaft 32 of the developing roller 30.

[0057] The drawer unit 90 has a conductive lever (not shown) that contacts the gear shaft 531, and an optical sensor (not shown). When the lever contacts the gear shaft 531, the conductive member 53 and the developing roller shaft 32 are electrically connected to the lever. When the image forming apparatus 100 is operating, the developing roller shaft 32 is maintained at a predetermined bias voltage by the power supplied from the lever.

[0058] The detection protrusion 521 partially covers the outer peripheral surface of the gear shaft 531. Therefore, after a new developer cartridge 1 is inserted into the drawer unit 90, when the detection gear 52 is rotating, the contact state between the lever and the gear shaft 531 changes depending on the shape of the detection gear 52. In other words, the lever temporarily separates from the gear shaft 531. The image forming apparatus 100 detects the displacement of the lever using an optical sensor. Then, the control unit 80 of the image forming apparatus 100 identifies whether the installed developer cartridge 1 is new and the specifications of the developer cartridge 1 based on the detection signal obtained from the optical sensor.

[0059] As described above, in this embodiment, the optical sensor detects the movement of the detection protrusion 521 via the lever. However, the optical sensor may directly detect the movement of the first protrusion. Also, a magnetic sensor or a contact sensor may be used instead of the optical sensor. Also, the movement of the detection protrusion 521 may be detected based on the presence or absence of electrical conduction between the lever and the gear shaft 531.

[0060] In this embodiment, the gear shaft 531 is a part of the conductive member 53. However, the gear shaft may be provided separately from the power supply path to the conductive member 53. For example, the casing 10 may further have a through hole penetrating the second end face 12 and a cap attached to the through hole, and the gear shaft may extend from the cap in the first direction.

[0061] The circumferential position and length of the detection protrusion 521 may differ from the example in FIG. 4. The detection gear 52 may have a plurality of detection protrusions 521. The number of detection protrusions 521, the circumferential position of each detection protrusion 521, the circumferential length of each detection protrusion 521, and the radial length of each detection protrusion 521 may differ depending on the specifications of the developer cartridge 1. In this way, by providing variations in the number and shape of the detection protrusions 521, various specifications of the developer cartridge 1 can be presented to the image forming apparatus 100.

[0062] The detection gear 52 may also be composed of multiple members. For example, the detection gear 52 and the detection protrusion 521 may be separate members. The detection gear may also 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 then change the position of the lever. The detection gear may also have a detection gear main body, a cam that rotates in response to the rotation of the detection gear main body, and a detection protrusion that is displaced by the rotation of the cam.

[0063] Furthermore, the detection gear 52 may be a movable gear that moves in a first direction as it rotates. The movement of the detection gear 52 in the first direction may cause the second agitator gear 51 and the detection gear 52 to disengage from each other. In this case, a plurality of gear teeth may be provided around the entire outer periphery of the detection protrusion 521. The detection gear 52 may move in a direction away from the second end face 12 or in a direction toward the second end face 12.

[0064] The second cover 54 is fixed to the second end surface 12 of the casing 10, for example, by screws. The second agitator gear 51, the detection gear 52, and the conductive member 53 are housed between the second end surface 12 and the second cover 54. The second cover 54 also has an opening 541. A portion of the detection protrusion 521 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.

[0065] 4, the casing 10 has a second columnar protrusion 55. The second columnar protrusion 55 protrudes in the first direction from the second end surface 12 of the casing 10. The second columnar protrusion 55 is exposed from the second cover 54.

[0066] <3. IC Chip Assembly> The IC chip assembly 60 is disposed on the outside of the first end surface 11 of the casing 10. FIG. 5 is an exploded perspective view of the IC chip assembly 60. FIG. 6 is a cross-sectional view of the IC chip assembly 60 cut along a plane perpendicular to the first direction. As shown in FIGS. 3 to 6, the IC chip assembly 60 has an IC chip 61, which is a storage medium, and a holder 62 that holds the IC chip 61. The IC chip 61 is fixed to the outer surface of the holder 62. The holder 62 is held between the casing 10 and the first cover 45. The IC chip 61 has an electrical contact surface 611. The electrical contact surface 611 is made of metal, which is a conductor. The IC chip 61 can store various information related to the developer cartridge 1.

[0067] Hereinafter, the direction intersecting the electrical contact surface 611 (in this embodiment, the direction perpendicular to the electrical contact surface 611) will be referred to as the "second direction." Also, the insertion direction of the developer cartridge 1 into the slot 91 of the drawer unit 90 will be referred to as the "third direction."

[0068] A portion of the holder 62 is covered by the first cover 45. The holder 62 has a first boss 621a, a second boss 621b, and a third boss 621c. The first boss 621a and the second boss 621b each extend in a first direction from the surface of the holder 62 opposite the surface facing the casing 10 toward the first cover 45. The first boss 621a and the second boss 621b are aligned in the third direction. Meanwhile, as shown in FIG. 3, the first cover 45 has a first through hole 451a and a second through hole 451b. The first through hole 451a and the second through hole 451b each penetrate the first cover 45 in the first direction. The first through hole 451a and the second through hole 451b are aligned in the third direction. The first boss 621a is inserted into the first through hole 451a. The second boss 621b is inserted into the second through-hole 451b.

[0069] Third boss 621c extends in a first 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 first direction at first end surface 11 of casing 10. Third boss 621c is inserted into recess 15. Note that each of first boss 621a, second boss 621b, and third boss 621c may have a cylindrical shape or another shape such as a rectangular pillar.

[0070] The size (inner dimension) of first through-hole 451a in the second direction is larger than the size (outer dimension) of first boss 621a. The size (inner dimension) of second through-hole 451b in the second direction is larger than the size (outer dimension) of second boss 621b. The size (inner dimension) of recess 15 in the second direction is larger than the size (outer dimension) of third boss 621c. Therefore, holder 62, together with first boss 621a, second boss 621b, and third boss 621c, can move in the second direction relative to casing 10 and first cover 45. When holder 62 moves in the second direction, IC chip 61 having electrical contact surface 611 also moves in the second direction together with holder 62.

[0071] Furthermore, the size (inner dimension) of first through-hole 451a in the third direction is larger than the size (outer dimension) of first boss 621a. The size (inner dimension) of second through-hole 451b in the third direction is larger than the size (outer dimension) of second boss 621b. The size (inner dimension) of recess 15 in the third direction is larger than the size (outer dimension) of third boss 621c. Therefore, holder 62, together with first boss 621a, second boss 621b, and third boss 621c, can move in the third direction relative to casing 10 and first cover 45. When holder 62 moves in the third direction, IC chip 61 having electrical contact surface 611 also moves in the third direction together with holder 62.

[0072] The holder 62 may be movable in the first direction between the first end surface 11 of the casing 10 and the first cover 45. The number of bosses provided on the holder 62, the number of through holes provided in the first cover 45, and the number of recesses provided in the casing 10 are not limited to the examples of this embodiment. The first cover 45 may have recesses into which the bosses are inserted, instead of through holes.

[0073] 5 and 6, the holder 62 has a first outer surface 710 and a second outer surface 720. The first outer surface 710 is located at one end of the holder 62 in the second direction. The second outer surface 720 is located at the other end of the holder 62 in the second direction. The second outer surface 720 is movable in the second direction relative to the first outer surface 710.

[0074] 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 outer surface 710. The IC chip 61 is fixed to a holding surface 620 included in the first outer surface 710. The second holder member 72 has a second outer surface 720. In the assembled holder 62, the first outer surface 710 and the second outer surface 720 are spaced apart in the second direction.

[0075] The coil spring 73 is an elastic member that extends in the second direction. The coil spring 73 is disposed between the first outer surface 710 and the second outer surface 720 in the second direction. The coil spring 73 expands and contracts in the second 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 second direction in the first state is longer than the length of the coil spring 73 in the second state. Therefore, the distance in the second direction between the first outer surface 710 and the second outer surface 720 in the first state is longer than the distance in the second direction between the first outer surface 710 and the second outer surface 720 in the second state. Furthermore, the length of the coil spring 73 in the second direction in at least the second state is shorter than the natural length of the coil spring 73.

[0076] 5 and 6, the first holder member 71 has a first claw portion 715a and a second claw portion 715b. The first claw portion 715a and the second claw portion 715b each protrude from the first holder member 71 in a direction intersecting the second direction. Meanwhile, the second holder member 72 has a first opening 721a and a second opening 721b. The first claw portion 715a is inserted into the first opening 721a. The second claw portion 715b is inserted into the second opening 721b. In the first state, the first claw portion 715a contacts the second holder member 72 at the edge of the first opening 721a on the side of the first outer surface 710. In the first state, the second claw portion 715b contacts the second holder member 72 at the edge of the second opening 721b on the side of the first outer surface 710. This prevents the length of the coil spring 73 in the second direction from becoming longer than in the first state. Also, the first holder member 71 is prevented from being detached from the second holder member 72. Meanwhile, in the second state, the first claw portion 715a and the second claw portion 715b are separated from the second holder member 72.

[0077] The second holder member 72 may have a recess or a step that can come into contact with the claw portion instead of the opening. Alternatively, the first holder member 71 may have the opening, recess, or step, and the second holder member 72 may have the claw portion.

[0078] Due to the dimensional difference between the first through hole 451a and the first boss 621a, the dimensional difference between the second through hole 451b and the second boss 621b, the dimensional difference between the recess 15 and the third boss 621c, and the expansion and contraction of the coil spring 73, the holding surface 620 of the holder 62 can move in the second direction relative to the casing 10.

[0079] Hereinafter, the position of the holding surface 620 in the second direction relative to the casing 10 before the developer cartridge 1 is attached to the drawer unit 90 will be referred to as the "initial position." Furthermore, when the developer cartridge 1 is attached to the drawer unit 90, the position of the holding surface 620 in the second direction relative to the casing 10 at the moment when the coil spring 73 is most compressed will be referred to as the "intermediate position." Furthermore, the position of the holding surface 620 in the second direction relative to the casing 10 when the electrical contact surface 611 contacts a terminal portion 913 (described later) will be referred to as the "contact position." Furthermore, the position of the holding surface 620 in the second direction relative to the casing 10 after the attachment of the developer cartridge 1 to the drawer unit 90 is complete will be referred to as the "final position."

[0080] In addition to the holding surface 620 described above, the first outer surface 710 further includes a first surface 711 , a second surface 712 , a third surface 713 , and a fourth surface 714 .

[0081] The first surface 711 is provided on one of both side portions of the holding surface 620 in the third direction, closer to the developing roller 30. The first surface 711 is inclined with respect to the electrical contact surface 611 of the IC chip 61 held on the holding surface 620.

[0082] Here, one end of the first outer surface 710 in the third direction is defined as a first outer end position 711a. Furthermore, one end of the holding surface 620 in the third direction is defined as a first inner end position 711b. As shown in FIG. 6 , the first 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 third direction, the first outer end position 711a is farther from the electrical contact surface 611 than the first inner end position 711b. Furthermore, as shown in FIG. 6 , a distance d1 in the second direction between the first outer end position 711a and the first inner end position 711b is greater than a distance d2 in the second direction between the electrical contact surface 611 and the first inner end position 711b.

[0083] The second surface 712 is provided on one of both side portions of the holding surface 620 in the third direction, the side farther from the developing roller 30. The second surface 712 is inclined with respect to the electrical contact surface 611 of the IC chip 61 held on the holding surface 620.

[0084] Here, the other end of the first outer surface 710 in the third direction is defined as a second outer end position 712a. The other end of the holding surface 620 in the third direction is defined as a second inner end position 712b. As shown in FIG. 6 , the second 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 and third directions, 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. 6 , a distance d3 in the second direction between the second outer end position 712a and the second inner end position 712b is greater than a distance d4 in the second direction between the electrical contact surface 611 and the second inner end position 712b.

[0085] The third surface 713 is provided on one of both sides of the electrical contact surface 611 in the first direction. The fourth surface 714 is provided on the other of both sides of the electrical contact surface 611 in the first direction. The third surface 713 and the fourth surface 714 each extend in the third direction. The electrical contact surface 611 is disposed at a position recessed toward the coil spring 73 relative to the third surface 713 and the fourth surface 714. In other words, the third surface 713 and the fourth surface 714 are farther from the coil spring 73 than the electrical contact surface 611 in the second direction.

[0086] The first surface 711, the second surface 712, the third surface 713, and the fourth surface 714 may each be flat or curved. However, it is preferable that the first surface 711, the second surface 712, the third surface 713, and the fourth surface 714 each be a smooth surface without any steps so that the developer cartridge 1 does not get caught when it is inserted into the drawer unit 90.

[0087] <4. About the drawer unit> FIG. 7 is a perspective view of the drawer unit 90. As described above, the drawer unit 90 has four slots 91 into which the developer cartridges 1 can be attached. Each slot 91 has an insertion opening 910. The insertion opening 910 is located at one of both ends of the slot 91 in the third direction, opposite the photosensitive drum 92. Each slot 91 also has a first guide plate 911 and a second guide plate 912. The first guide plate 911 and the second guide plate 912 are located at one end of each slot 91 in the first direction.

[0088] 8 is a cross-sectional view of the first guide plate 911 and the second guide plate 912, taken perpendicular to the first direction. As shown in FIGS. 7 and 8, the first guide plate 911 and the second guide plate 912 are disposed facing each other with a gap in the second direction. The first guide plate 911 and the second guide plate 912 extend along the first direction and the third direction, respectively.

[0089] The first guide plate 911 has a terminal portion 913. The terminal portion 913 is an electrical contact that can come into contact with the electrical contact surface 611 of the IC chip 61. The terminal portion 913 protrudes in the second direction from the surface of the first guide plate 911 toward the second guide plate 912. The terminal portion 913 is electrically connected to the control unit 80 in the image forming apparatus 100. The material of the terminal portion 913 is, for example, a metal that is a conductor.

[0090] As shown in the enlarged view of FIG. 7 and in FIG. 8, the first guide plate 911 has a guide protrusion 914. The guide protrusion 914 is located closer to the insertion opening 910 than the terminal portion 913. The guide protrusion 914 protrudes from the first guide plate 911 toward the second guide plate 912. The first guide plate 911 also has a first guide surface 915. In the example of FIG. 8, the inclined surface of the guide protrusion 914 on the insertion opening side serves as the first guide surface 915. On the other hand, the second guide plate 912 has a second guide surface 916. The distance in the second direction between the first guide surface 915 and the second guide surface 916 gradually decreases as the second guide plate approaches the photosensitive drum 92 in the third direction.

[0091] When the developer cartridge 1 is inserted into the drawer unit 90, the first outer surface 710 of the holder 62 contacts the first guide surface 915, and the second outer surface 720 of the holder 62 contacts the second guide surface 916. This changes the distance in the second direction between the first outer surface 710 and the second outer surface 720.

[0092] The first guide plate 911 also has a third guide surface 917 and a fourth guide surface 918. The third guide surface 917 and the fourth guide surface 918 position the holder 62 in the first direction when the developer cartridge 1 is inserted into the drawer unit 90. The third guide surface 917 and the fourth guide surface 918 are located closer to the insertion opening 910 than the first guide surface 915. The third guide surface 917 and the fourth guide surface 918 are disposed with a gap between them in the first direction. The gap between the third guide surface 917 and the fourth guide surface 918 in the first direction gradually decreases as they approach the first guide surface 915.

[0093] 8, the second guide plate 912 has a stopper surface 919. The stopper surface 919 is a surface for restricting movement of the holder 62 toward the photosensitive drum 92 after the developer cartridge 1 is inserted into the drawer unit 90. The stopper surface 919 is located closer to the photosensitive drum 92 than the second guide surface 916. The stopper surface 919 also extends from the surface of the second guide plate 912 facing the first guide plate 911 toward the first guide plate 911. In the example of FIG. 8, the stopper surface 919 extends obliquely in the second and third directions.

[0094] The stopper surface may be provided on at least one of the first guide plate 911 and the second guide plate 912. That is, the first guide plate 911 may have the stopper surface. In this case, the stopper surface is located closer to the photosensitive drum 92 than the terminal portion 913. The stopper surface extends from the surface of the first guide plate 911 facing the second guide plate 912 toward the second guide plate 912.

[0095] The first guide plate 911 also has a fifth guide surface 920. The fifth guide surface 920 is a surface for restricting movement of the holder 62 toward the insertion opening 910 after the developer cartridge 1 is inserted into the drawer unit 90. The fifth guide surface 920 is located between the terminal portion 913 and the first guide surface 915 in the third direction. In the example of FIG. 8 , the inclined surface of the guide protrusion 914 on the terminal portion 913 side serves as the fifth guide surface 920. However, it is sufficient that the fifth guide surface 920 is provided on at least one of the first guide plate 911 and the second guide plate 912.

[0096] As shown in FIG. 7 , the drawer unit 90 also has a plurality of separation levers 93. As shown in FIG. 8 , the drawer unit 90 also has a plurality of pressure members 94 and a plurality of pushing members 95. The pressure members 94 are provided on both sides of each slot 91 in the first direction. The pushing members 95 are also provided on both sides of each slot 91 in the first direction. When the developer cartridge 1 is installed in the drawer unit 90, the first columnar protrusion 46 is positioned between the pressure member 94 and the pushing member 95 on one side of the slot 91 in the first direction. The second columnar protrusion 55 is positioned between the pressure member 94 and the pushing member 95 on the other side of the slot 91 in the first direction. The pressure member 94 presses the first columnar protrusion 46 and the second columnar protrusion 55 in the third direction toward the photosensitive drum 92.

[0097] The pressing member 95 works in conjunction with the separating lever 93. During a separating operation, which will be described later, the separating lever 93 is pressed by a driving force from the image forming apparatus 100. This causes the pressing member 95 to move in the third direction toward the pressure member 94. As a result, the first columnar projection 46 and the second columnar projection 55 are each pressed by the pressing member 95. Then, the first columnar projection 46 and the second columnar projection 55 each move against the pressure of the pressure member 94. As a result, the casing 10 and the developing roller 30 of the developer cartridge 1 move in the third direction.

[0098] <5. Operation when worn> Next, a description will be given of the operation when the developer cartridge 1 is attached to the drawer unit 90. Figures 9 to 15 are diagrams showing the state when the developer cartridge 1 is attached to one slot 91 of the drawer unit 90.

[0099] When the developer cartridge 1 is inserted into the slot 91, the developer cartridge 1 is first positioned opposite the insertion opening 910 of the slot 91, as shown in FIG. 9. At this time, the first outer surface 710 and the second outer surface 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 relative to the casing 10 in the second direction is the initial position described above. The developer cartridge 1 is inserted into the slot 91 in the third direction, as indicated by the dashed arrow in FIG. 9.

[0100] When the developer cartridge 1 is inserted into the slot 91, as shown in FIG. 10 , the first surface 711 of the holder 62 comes into contact with the end of the first guide plate 911 in the third direction. Then, the first surface 711 is pressed by the first guide plate 911, causing the holder 62 to move in the second 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 second direction between the first guide plate 911 and the second guide plate 912.

[0101] Moreover, the holder 62 is inserted in the third direction while contacting the third guide surface 917 and the fourth guide surface 918. This positions the holder 62 in the first direction. In this manner, in this embodiment, the holder 62 is positioned in the first direction before the electrical contact surface 611 contacts the terminal portion 913. Therefore, after the electrical contact surface 611 contacts the terminal portion 913, the position of the electrical contact surface 611 relative to the terminal portion 913 is prevented from shifting in the first direction. This prevents the electrical contact surface 611 from rubbing against the electrical contact surface 611.

[0102] 11 , the first outer surface 710 of the first holder member 71 comes into contact with the first guide plate 911. The first outer surface 710 moves in the third direction along the surface of the first guide plate 911. Furthermore, the second outer surface 720 of the second holder member 72 comes into contact with the second guide plate 912. The second outer surface 720 moves in the third direction along the surface of the second guide plate 912. The coil spring 73 contracts in the second direction more than in the first state.

[0103] When the developer cartridge 1 is further inserted in the third direction, the first holder member 71 contacts the first guide surface 915, and the second holder member 72 contacts the second guide surface 916. This causes the first holder member 71 and the second holder member 72 to approach each other in the second direction. That is, the first outer surface 710 and the second outer surface 720 approach each other in the second direction. Therefore, the length of the coil spring 73 in the second direction gradually shortens. Eventually, as shown in FIG. 12 , when the third surface 713 and the fourth surface 714 of the first holder member 71 contact the tops of the guide protrusions 914, the length of the coil spring 73 in the second direction becomes shortest. That is, the coil spring 73 reaches its shortest state, which is shorter than the second state described above. Furthermore, the position of the holding surface 620 in the second direction relative to the casing 10 becomes the intermediate position described above.

[0104] In this way, this IC chip assembly 60 can change the position of the holding surface 620 that holds the IC chip 61 in the second 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 second direction along the guide protrusion 914. Therefore, the developer cartridge 1 can be inserted into the drawer unit 90 while suppressing friction on the electrical contact surface 611 of the IC chip 61.

[0105] In particular, in the developer cartridge 1 of this embodiment, the electrical contact surface 611 of the IC chip 61 is disposed at a position recessed from the third surface 713 and the fourth surface 714. Therefore, in the state shown in Figure 12, the top of the guide protrusion 914 contacts only the third surface 713 and the fourth surface 714, and does not contact the electrical contact surface 611. Therefore, rubbing of the guide protrusion 914 against the electrical contact surface 611 can be prevented.

[0106] Thereafter, when the developer cartridge 1 is further inserted in the third direction, the third surface 713 and the fourth surface 714 pass by the guide protrusion 914. Then, as shown in FIG. 13, the second surface 712 comes into contact with the guide protrusion 914. As a result, the coil spring 73 expands again from its shortest state and reaches the second state described above. As a result, as shown in FIG. 14, the electrical contact surface 611 of the IC chip 61 comes into contact with the terminal portion 913. This enables the control unit 80 of the image forming apparatus 100 to at least one of read information from and write information to the IC chip 61.

[0107] The length in the second direction of coil spring 73 in the second state is shorter than the length in the second direction of coil spring 73 in the first state and longer than the length in the second direction of coil spring 73 in the shortest state. Furthermore, the relative position in the second direction of holding surface 620 with respect to casing 10 is the contact position described above.

[0108] In this way, the electrical contact surface 611 comes into direct contact with the terminal portion 913 after the first outer surface 710 has climbed over the guide protrusion 914. Therefore, after contact, the contact position of the terminal portion 913 with respect to the electrical contact surface 611 is unlikely to change. This further reduces rubbing of the electrical contact surface 611.

[0109] The length in the second direction between the terminal portion 913 and the second guide plate 912 is shorter than the length in the second direction between the electrical contact surface 611 and the second outer surface 720 of the developer cartridge 1 before installation. Therefore, in the state shown in FIG. 14 , the length in the second direction of the coil spring 73 is shorter than the natural length of the coil spring 73. For this reason, the elastic force (repulsive force) of the coil spring 73 presses the electrical contact surface 611 against the terminal portion 913. This allows good contact to be maintained between the electrical contact surface 611 and the terminal portion 913.

[0110] The IC chip assembly 60 is fixed in a sandwiched state between the terminal portion 913 and the second guide plate 912. Then, in this embodiment, the casing 10 is tilted in the second direction as indicated by the dashed arrow in FIG. 15 . This causes the developing roller 30 to contact the photosensitive drum 92 of the drawer unit 90. At this time, the position of the holding surface 620 relative to the casing 10 in the second direction changes from the contact position to the final position. Furthermore, the first boss 621a moves in the second direction within the first through-hole 451a. The second boss 621b moves in the second direction within the second through-hole 451b. The third boss 621c moves in the second direction within the recess 15. This causes the holder 62 to be out of contact with the casing 10 and the first cover 45. Therefore, vibrations are less likely to be transmitted from the drive units, such as the first gear unit 40, to the IC chip assembly 60 during printing operations in the image forming apparatus 100. This allows the electrical contact surface 611 and the terminal portion 913 to be maintained in a better contact state.

[0111] <6. Separation operation> After the developer cartridge 1 is installed, the image forming apparatus 100 can temporarily separate the developer roller 30 from the photosensitive drum 92, that is, perform a so-called "separating operation."

[0112] 15 is completed, the first columnar projection 46 and the second columnar projection 55 each come into contact with the pressure member 94. The pressure member 94 presses the first columnar projection 46 and the second columnar projection 55 in a direction that brings them closer to the photosensitive drum 92. This presses the developing roller 30 against the photosensitive drum 92. In other words, the developing roller 30 and the photosensitive drum 92 are maintained in contact with each other.

[0113] FIG. 16 illustrates a state in which the separation operation is performed. During the separation operation, the separation lever 93 is pressed by a driving force from the image forming apparatus 100. This causes the pressing member 95 to move in the third direction toward the pressure member 94. As a result, the pressing member 95 located on one side in the first direction contacts the first columnar protrusion 46 and presses the first columnar protrusion 46 toward the insertion opening 910 against the pressure of the pressure member 94. Meanwhile, the pressing member 95 located on the other side in the first direction contacts the second columnar protrusion 55 and presses the first columnar protrusion 46 toward the insertion opening 910 against the pressure of the pressure member 94. As a result, the casing 10 and the developing roller 30 of the developer cartridge 1 move in the third direction, as indicated by the dashed arrow in FIG. 16. As a result, the developing roller 30 and the photosensitive drum 92 are separated from each other.

[0114] In either the contact state or the separated state, the IC chip assembly 60 is fixed in a state sandwiched between the terminal portion 913 and the second guide plate 912. The electrical contact surface 611 is in contact with the terminal portion 913. The holder 62 is not in contact with the casing 10 and the first cover 45. Furthermore, the first guide plate 911 and the second guide plate 912 are also not in contact with the casing 10 and the first cover 45. Therefore, during the separating operation, the casing 10 can be moved relative to the holder 62 with the holder 62 fixed between the first guide plate 911 and the second guide plate 912.

[0115] That is, during the separation operation, the casing 10 and the developing roller 30 move in the third direction, but the position of the IC chip assembly 60 relative to the drawer unit 90 does not change. Furthermore, the state of the coil spring 73 remains unchanged, remaining in the second state. That is, the position of the casing 10 in the third direction changes while the position of the electrical contact surface 611 relative to the drawer unit 90 remains fixed. Therefore, the electrical contact surface 611 and the terminal portion 913 are maintained in contact with each other. Furthermore, rubbing of the electrical contact surface 611 during the separation operation is reduced.

[0116] Furthermore, even when the image forming apparatus 100 is transported with the developer cartridge 1 attached to the drawer unit 90, the electrical contact surface 611 and the terminal portion 913 are maintained in contact with each other. This further reduces friction on the electrical contact surface 611.

[0117] In the above embodiment, the direction in which the developing roller 30 separates from the photosensitive drum 92 during the separation operation (separation direction) is the third direction. However, the separation direction may be a direction other than the third direction. The separation direction may be any direction as long as it intersects with the direction in which the electrical contact surface 611 and the terminal portion 913 face each other.

[0118] <7. Variations> Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. Various modifications will be described below, focusing on the differences from the above embodiment.

[0119] In the above embodiment, both the first guide surface and the second guide surface are inclined with respect to the third direction. However, one of the first guide surface and the second guide surface may extend parallel to the third direction, and only the other may be inclined with respect to the third direction. Also, in the above embodiment, both the first guide surface and the second guide surface are flat surfaces. However, one or both of the first guide surface and the second guide surface may be curved surfaces.

[0120] In the above embodiment, the boss provided on the holder is inserted into the through-hole provided on the first cover. However, the boss may be provided on the first cover, and the holder 62 may be provided with a through-hole or recess into which the boss is inserted. Also, in the above embodiment, the boss provided on the holder is inserted into a recess provided on the casing. However, the boss may be provided on the casing, and the holder 62 may be provided with a through-hole or recess into which the boss is inserted.

[0121] In the above embodiment, the coil spring 73 is used as the elastic member. However, other types of springs, such as a leaf spring or a torsion spring, may be used instead of the coil spring 73. The IC chip assembly may not have an elastic member. That is, the IC chip assembly may not expand or contract in the second direction. In this case, the image forming apparatus may have a mechanism that applies an external force to the IC chip assembly to press the electrical contact surface against the terminal portion.

[0122] In the above embodiment, the developer cartridge is mounted in the drawer unit. However, the developer cartridge may be mounted in a drum cartridge having a photosensitive drum, rather than in the drawer unit. The drum cartridge with the developer cartridge mounted therein may then be mounted in the image forming apparatus. The developer cartridge may also be mounted directly in the main body of the image forming apparatus without using the drawer unit or drum cartridge. The photosensitive drum may be provided within the main body of the image forming apparatus.

[0123] In the above embodiment, an IC chip having an 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 remaining portion of the IC chip may be located elsewhere in the developer cartridge. The electrical contact surface may also be an electrode separate from the storage medium such as the IC chip. The separate electrode may be, for example, an electrode for supplying power to the developer roller 30. In this case, the electrical contact surface is electrically connected to the developer roller 30 via a harness.

[0124] In the above embodiment, the gears in the first gear unit and the second gear unit are engaged with each other by meshing of gear teeth. However, the gears in the first gear unit and the second gear unit may be engaged with each other by friction. 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.

[0125] In the above embodiment, when the separating operation is performed, the casing is moved in the third direction relative to the holder while the electrical contact surface and the terminal portion are kept in contact with each other. However, for a purpose other than the separating operation, the housing may be moved in the third direction relative to the holder while the electrical contact surface and the terminal portion are kept in contact with each other.

[0126] Furthermore, the detailed shapes of the components constituting the image forming apparatus may differ from those shown in the drawings of the present application. Furthermore, the elements appearing in the above-described embodiments and modifications may be combined as appropriate within the scope of not causing any contradiction. [Explanation of symbols]

[0127] 1 Developer cartridge 10 Casing 11 First end surface 12 Second end face 13 Containment Room 20 Agitator 30 Developing roller 40 First Gear Section 41 Coupling 42 Developing roller gear 43 Idle Gear 44 First agitator gear 45 1st cover 46 First columnar process 50 Second Gear Section 51 Second agitator gear 52 Detection Gear 53 Conductive materials 54 Second Cover 55 Second columnar process 60 IC chip assembly 61 IC chip 62 Holder 71 first holder member 72 second holder member 73 Coil spring 90 Drawer Unit 91 Slots 92 Photosensitive drum 93 Separation lever 94 Pressure member 95 Pressing member 100 Image forming device 521 Detection protrusion 611 Electrical Contact Surface 710 First outer surface 720 Second outer surface 911 First guide plate 912 Second guide plate 913 Terminal section 914 Guide protrusion 915 First guide surface 916 Second guide surface 917 Third guide surface 918 4th guide surface 919 Stopper surface 920 5th guide surface

Claims

1. An image forming apparatus, a housing capable of accommodating a developer; a storage medium having an electrical contact surface; a first holder that holds the storage medium and moves relative to the housing; a second holder connected to the housing and the first holder and movable relative to the housing and the first holder; a developing cartridge including the an electrical contact that contacts the electrical contact surface of the developer cartridge; Equipped with an electrical contact surface and an electrical contact point, the electrical contact point being in contact with each other; and a housing that is movable relative to the first holder and the second holder.

2. 2. The image forming apparatus according to claim 1, the housing has a boss, The image forming apparatus is characterized in that the second holder has a through hole into which the boss is inserted.

3. 2. The image forming apparatus according to claim 1, an image forming apparatus comprising: a stretchable elastic member positioned between the first holder and the second holder;

4. 4. The image forming apparatus according to claim 3, The image forming apparatus is characterized in that the elastic member is a spring.

5. 2. The image forming apparatus according to claim 1, The developing cartridge is a developing roller supported by the housing, the developing roller being movable between a position in contact with the photosensitive drum and a position spaced apart from the photosensitive drum while the electrical contact surface and the electrical contact are in contact with each other; An image forming apparatus comprising:

6. 2. The image forming apparatus according to claim 1, The image forming apparatus is characterized in that the electrical contact is electrically connected to a circuit board.

7. a housing capable of accommodating a developer; a storage medium having an electrical contact surface; a first holder that holds the storage medium and moves relative to the housing; a second holder connected to the housing and the first holder and movable relative to the housing and the first holder; A developing cartridge comprising: A developing cartridge, which is attached to an image forming apparatus and characterized in that the housing is movable relative to the first holder and the second holder with the electrical contact surface in contact with an electrical contact of the image forming apparatus.

8. 8. The developing cartridge according to claim 7, A developing cartridge comprising: an expandable elastic member positioned between the first holder and the second holder.

9. 9. The developing cartridge according to claim 8, The developing cartridge is characterized in that the elastic member is a spring.

10. 8. The developing cartridge according to claim 7, the housing has a boss, The second holder has a through hole into which the boss is inserted.

11. 8. The developing cartridge according to claim 7, The developing cartridge is characterized in that it has a developing roller supported by the housing, and is movable between a position in contact with the photosensitive drum and a position away from the photosensitive drum while the electrical contact surface is in contact with an electrical contact provided in the image forming device.

Images