Image forming device

Abstract

To provide, in an image forming apparatus that allows mounting of a developing cartridge mounted on a drum cartridge, a configuration that allows execution of separation operation while preventing rubbing of an electrical contact surface against an electrical contact and can reduce the size of the drum cartridge.SOLUTION: A developing cartridge has a storage medium having an electrical contact surface 511, and a holder 52. The holder 52 has a first outer surface 52A and a second outer surface 52B. The electrical contact surface 511 is held on the first outer surface 52A. An image forming apparatus has a first guide surface 81 and a second guide surface 82. The first guide surface 81 guides the first outer surface 52A of the holder 52. The second guide surface 82 guides the second outer surface 52B of the holder 52. The drum cartridge does not thus need to be provided with a surface for supporting the second outer surface 52B. Consequently, the drum cartridge can be reduced in size.SELECTED DRAWING: Figure 12

Description

[Technical Field]

[0001] The present disclosure relates to an image forming apparatus. [Background technology]

[0002] Electrophotographic image forming apparatuses such as laser printers and LED printers are known. A developer cartridge is used in the image forming apparatus. The developer cartridge has a developer roller for supplying developer. A conventional image forming apparatus is described in, for example, Patent Document 1.

[0003] The developer cartridge in Patent Document 1 is attached to a drum cartridge. The drum cartridge has a photosensitive drum. When the developer cartridge is attached to the drum cartridge, the photosensitive drum and the developer roller come into contact with each other. Then, the drum cartridge with the attached developer cartridge is attached to an image forming apparatus.

[0004] The developer cartridge of Patent Document 1 includes a storage medium and a holder. The storage medium is, for example, an IC chip. The storage medium is held on the outer surface of the holder. The storage medium has an electrical contact surface. When a drum cartridge with the developer cartridge installed is installed in an image forming device, the electrical contact surface of the storage medium comes into contact with an electrical contact of the image forming device. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2018-189740 Summary of the Invention [Problem to be solved by the invention]

[0006] The image forming apparatus performs a separation operation to separate the developing roller from the photosensitive drum. When performing the separation operation, it is necessary to prevent the electrical contact surface of the storage medium from rubbing against the electrical contact of the image forming apparatus.

[0007] In order to prevent the electrical contact surface from rubbing against the electrical contact, in Patent Document 1, when the drum cartridge with the developer cartridge attached is attached to the image forming device, a holder is held between the electrical contact of the image forming device and the frame of the drum cartridge. However, if a surface for supporting the outer surface of the holder is provided on the drum cartridge as in Patent Document 1, it becomes difficult to reduce the size of the drum cartridge.

[0008] The object of the present disclosure is to provide a structure in an image forming device that can accommodate a developing cartridge attached to a drum cartridge, which can perform a separation operation while suppressing friction of the electrical contact surface against the electrical contact, and which can reduce the size of the drum cartridge. [Means for solving the problem]

[0009] The first disclosure is an image forming device into which a developer cartridge attached to a drum cartridge can be attached, the developer cartridge including: a developer roller rotatable about a first rotation axis extending in a first direction; a housing capable of accommodating a developer, the housing having the developer roller located at one end in a second direction of the housing; a storage medium having an electrical contact surface; and a holder located at one end of the housing in the first direction and holding the electrical contact surface, the holder having a first outer surface located at one end of the holder in a third direction intersecting the electrical contact surface and holding the electrical contact surface; a second outer surface located at the other end of the holder in the third direction and spaced apart from the first outer surface in the third direction; and an elastic member located between the first outer surface and the second outer surface and stretchable in the third direction, and the drum cartridge includes a photosensitive drum rotatable about a second rotation axis extending in the first direction. The image forming apparatus includes an electrical contact that can come into contact with the electrical contact surface, and a main body frame into which the developing cartridge is attached when the developing cartridge is attached to the drum cartridge, the main body frame having a holder guide extending in the second direction, the holder guide including a first guide surface that guides the first outer surface when the developing cartridge is attached to the main body frame, the first guide surface being on which the electrical contact is located, and a second guide surface that guides the second outer surface when the developing cartridge is attached to the main body frame, and when the electrical contact surface is in contact with the electrical contact and the second outer surface is in contact with the second guide surface, the housing is movable in the second direction relative to the holder between a contact position where the developing roller contacts the photosensitive drum and a separation position where the developing roller is separated from the photosensitive drum.

[0010] The second disclosure is the image forming apparatus of the first disclosure, characterized in that the holder has a first holder member having the first outer surface and a second holder member having the second outer surface, and the second holder member is movable in the third direction relative to the first holder member.

[0011] The third disclosure is an image forming apparatus according to the first or second disclosure, characterized in that the holder guide further has a surface facing the holder in the second direction when the developing cartridge is attached to the main body frame.

[0012] The fourth disclosure is the image forming apparatus of the third disclosure, characterized in that when the developing cartridge is attached to the main body frame, the surface is away from the holder in the second direction.

[0013] The fifth disclosure is an image forming apparatus according to any one of the first to fourth disclosures, characterized in that when the developing cartridge is attached to the main body frame, the first outer surface approaches the second outer surface in the third direction, and the second outer surface approaches the first outer surface in the third direction.

[0014] The sixth disclosure is the image forming apparatus of the fifth disclosure, characterized in that when the developing cartridge is not attached to the main body frame, the length of the elastic member in the third direction is a first length, and when the developing cartridge is attached to the main body frame, the length of the elastic member in the third direction is a second length that is shorter than the first length.

[0015] The seventh disclosure is an image forming apparatus according to any one of the first to sixth disclosures, characterized in that the drum cartridge further has a drum separation lever that is rotatable about a drum axis extending in the first direction, and when the housing is positioned at the contact position, the drum separation lever is separated from the housing, and when the housing is positioned at the separation position, the drum separation lever presses the housing.

[0016] An eighth disclosure is an image forming apparatus according to any one of the first to seventh disclosures, characterized in that the drum cartridge further has a pressing member that presses the developing cartridge toward the photosensitive drum when the developing cartridge is attached to the drum cartridge.

[0017] The ninth disclosure is an image forming device according to any one of the first to eighth disclosures, characterized in that the drum cartridge has a protrusion that contacts the housing when the developing cartridge is attached to the drum cartridge, and the housing contacts the protrusion when the housing moves between the contact position and the separated position.

[0018] A tenth disclosure is the image forming apparatus of the ninth disclosure, wherein the protrusion has a curved surface.

[0019] An eleventh disclosure is the image forming apparatus of any one of the first to tenth disclosures, characterized in that it includes a plurality of the developing cartridges attached to the drum cartridge. [Effects of the Invention]

[0020] According to the first to eleventh disclosures, the second outer surface of the holder contacts the second guide surface of the image forming device, not the drum cartridge. This eliminates the need to provide the drum cartridge with a surface for supporting the second outer surface. This allows the drum cartridge to be made smaller. Furthermore, the developing roller can be moved relative to the photosensitive drum without changing the position of the holder relative to the main body frame. This reduces friction of the electrical contact surface against the electrical contact.

[0021] Furthermore, according to the third disclosure, the range of movement of the holder in the second direction can be limited when the developing cartridge is attached to the main body frame.

[0022] Furthermore, according to the fourth disclosure, the surface and the holder are normally not in contact with each other, which prevents the surface from excessively restricting the movement of the holder.

[0023] According to the seventh disclosure, the developing roller can be separated from the photosensitive drum by operating the drum separation lever. Furthermore, because the second outer surface of the holder is supported by the main body frame, even if the drum cartridge vibrates due to operation of the drum separation lever, the vibration is less likely to be transmitted to the holder. Therefore, friction between the electrical contact surfaces and the electrical contacts can be further reduced.

[0024] Furthermore, according to the ninth disclosure, the housing can be moved smoothly along the protrusion during the separation operation. This makes it possible to suppress vibration during the separation operation. As a result, it is possible to further suppress rubbing of the electrical contact surfaces against the electrical contacts.

[0025] Furthermore, according to the tenth disclosure, the housing can be moved more smoothly along the multiple protrusions during the separating operation, thereby further suppressing vibrations during the separating operation.

[0026] Furthermore, according to the eleventh disclosure, each of the multiple drum cartridges can be made smaller, which allows the image forming apparatus to be made even smaller. [Brief explanation of the drawings]

[0027] [Figure 1] FIG. 1 is a schematic diagram of an image forming apparatus. [Figure 2] FIG. 2 is a perspective view of the process cartridge. [Figure 3] FIG. [Figure 4] FIG. 2 is a cross-sectional view of the developing cartridge. [Figure 5] FIG. 2 is an exploded perspective view of the developing cartridge in the vicinity of the memory assembly. [Figure 6] FIG. 2 is a perspective view of the drum cartridge. [Figure 7] FIG. 2 is a view of the drum cartridge as seen from the second end side. [Figure 8] FIG. [Figure 9] FIG. [Figure 10] FIG. [Figure 11] 4 is a cross-sectional view of the image forming apparatus when the developing cartridge is mounted on the main body frame. FIG. [Figure 12] 2 is a cross-sectional view of the image forming apparatus in a state where a developing cartridge is mounted on a main body frame. [Figure 13] FIG. 10 is a perspective view of the process cartridge when a separating operation is performed. [Figure 14] FIG. 10 is a perspective view of the process cartridge when a separating operation is performed. [Figure 15] FIG. 10 is a cross-sectional view of the image forming apparatus when a separating operation is performed. DETAILED DESCRIPTION OF THE INVENTION

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

[0029] In the following, the direction in which the rotation axis of the developing roller extends will be referred to as the "first direction." Furthermore, the direction in which one end of the housing of the developing cartridge where the developing roller is located is aligned with the other end on the opposite side will be referred to as the "second direction." Furthermore, the direction intersecting with the electrical contact surface described below will be referred to as the "third direction." The first direction and the second direction intersect with each other (preferably perpendicular). The second direction and the third direction intersect with each other. The third direction and the first direction intersect with each other (preferably perpendicular).

[0030] <1. Configuration of image forming device> 1 is a schematic diagram of an image forming apparatus 100. The image forming apparatus 100 is an electrophotographic printer. Specifically, the image forming apparatus 100 is a laser printer or an LED printer.

[0031] The image forming apparatus 100 has a main body frame 90. The main body frame 90 has four slots 91. The four slots 91 are aligned in the third direction. A process cartridge 3 can be attached to each slot 91. That is, four process cartridges 3 can be attached to the main body frame 90. However, the number of process cartridges 3 that can be attached to the main body frame 90 may be one to three, or may be five or more.

[0032] The process cartridge 3 has a developing cartridge 1 and a drum cartridge 2. The developing cartridge 1 is attached to the drum cartridge 2. The developing cartridge 1, attached to the drum cartridge 2, is then attached to a slot 91 in a main body frame 90.

[0033] The four developer cartridges 1 contain developers of different colors (e.g., cyan, magenta, yellow, and black). The developers are, for example, toner. The image forming apparatus 100 forms an image on printing paper using the developers supplied from the four developer cartridges 1.

[0034] Each of the four developer cartridges 1 has a memory 51. The memory 51 is a storage medium from which information can be read and written. The image forming apparatus 100 also has a control unit 92. When a process cartridge 3 is attached to a slot 91 in the main body frame 90, the memory 51 of each developer cartridge 1 and the control unit 92 are electrically connected. The control unit 92 is formed, for example, by a circuit board. The control unit 92 has a processor such as a CPU and various memories. The control unit 92 executes various processes in the image forming apparatus 100 by causing the processor to operate in accordance with a program.

[0035] <2. Process cartridge> <2.1. About the developing cartridge> FIG. 2 is a perspective view of the process cartridge 3. As described above, the process cartridge 3 has the developer cartridge 1 and the drum cartridge 2. The developer cartridge 1 is detachable from the drum cartridge 2. A user of the image forming apparatus 100 can replace only one of the developer cartridge 1 and the drum cartridge 2 with a new one. Therefore, the lifespan of both the developer cartridge 1 and the drum cartridge 2 can be effectively utilized.

[0036] Fig. 3 is a perspective view of the developer cartridge 1. Fig. 4 is a cross-sectional view of the developer cartridge 1 cut along a plane perpendicular to the first direction. As shown in Figs. 3 and 4, the developer cartridge 1 has a casing 10, an agitator 20, a development roller 30, a supply roller 33, a layer thickness regulating blade 34, a gear portion 40, and a memory assembly 50.

[0037] The casing 10 is a housing capable of containing a developer. The casing 10 extends in a first direction. The casing 10 has a first end surface 11 and a second end surface 12. The first end surface 11 is located at one end of the casing 10 in the first direction. The second end surface 12 is located at the other end of the casing 10 in the first direction. The first end surface 11 and the second end surface 12 are spaced apart in the first direction. The casing 10 also has a storage chamber 13. The developer is stored in the storage chamber 13. The casing 10 also has an opening 14. The opening 14 is located at one end of the casing 10 in the second direction. The storage chamber 13 and the external space of the casing 10 are in communication with each other via the opening 14.

[0038] The agitator 20 has an agitator shaft 21 and an agitator blade 22. The agitator shaft 21 extends along the 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 located inside the containing chamber 13. An agitator gear included in the gear unit 40 is connected to one end of the agitator shaft 21 in the first direction. The agitator shaft 21 and the agitator blade 22 rotate together with the agitator gear. When the agitator blade 22 rotates, the developer in the containing chamber 13 is agitated.

[0039] The developing roller 30 is a roller that can rotate about a first rotation axis that extends in the first direction. The developing roller 30 is located in the opening 14 of the casing 10. In other words, the developing roller 30 is located at one end of the casing 10 in the second direction.

[0040] 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 extending in a first direction. The developing roller main body 31 is made of, for example, 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, for example, metal or conductive resin. The developing roller main body 31 is fixed to the developing roller shaft 32.

[0041] One end of the developing roller shaft 32 in the first direction is fixed to a developing roller gear included in the gear portion 40. When the developing roller gear rotates, the developing roller shaft 32 also rotates, and together with the developing roller shaft 32, the developing roller main body 31 also rotates.

[0042] 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.

[0043] The supply roller 33 is located between the agitator 20 and the developing roller 30. The supply roller 33 is rotatable about a rotation axis extending in the first direction. When the developer cartridge 1 receives a driving force, the 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 33. At that time, the developer is frictionally charged between the supply roller 33 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 body 31 by the electrostatic force between the developing roller shaft 32 and the developer.

[0044] The layer thickness regulating blade 34 shapes the developer supplied to the outer peripheral surface of the developing roller main body 31 to a uniform thickness. Thereafter, the developer on the outer peripheral surface of the developing roller main body 31 is supplied to a photosensitive drum 70 (described later) of the drum cartridge 2. At this time, the developer moves from the developing roller main body 31 to the photosensitive drum 70 in accordance with the electrostatic latent image formed on the outer peripheral surface of the photosensitive drum 70. As a result, the electrostatic latent image is made visible on the outer peripheral surface of the photosensitive drum 70.

[0045] The gear unit 40 is located on the first end surface 11 of the casing 10. The gear unit 40 has a plurality of gears, including the agitator gear and developing roller gear described above, a coupling 41, and a gear cover 45. The gear cover 45 is fixed to the first end surface 11 of the casing 10, for example, by screws. At least some of the plurality of gears are located between the first end surface 11 and the gear cover 45. The coupling 41 is exposed through the gear cover 45. When the process cartridge 3 is installed in the image forming apparatus 100, a drive shaft of the image forming apparatus 100 is connected to the coupling 41. Then, rotation of the drive shaft is transmitted to the plurality of gears, including the agitator gear and developing roller gear, via the coupling 41.

[0046] The developing cartridge 1 also has a holder cover 47. The holder cover 47 is fixed to the gear cover 45. The holder cover 47 is located on the opposite side of the gear cover 45 from the casing 10 in the first direction.

[0047] The gears included in the gear unit 40 may transmit a rotational force by meshing of teeth, or may transmit a rotational force by friction.

[0048] The memory assembly 50 is located on the first end surface 11 of the casing 10. More specifically, the memory assembly 50 is located on the outer surface of the gear cover 45. FIG. 5 is an exploded perspective view of the developer cartridge 1 in the vicinity of the memory assembly 50. As shown in FIG. 5, the memory assembly 50 has a memory 51, which is a storage medium, and a holder 52 that holds the memory 51. The memory 51 is held on the outer surface of the holder 52.

[0049] The memory 51 is, for example, an IC chip. The memory 51 has an electrical contact surface 511. The electrical contact surface 511 is made of metal, which is a conductor. The memory 51 can store various pieces of information related to the developing cartridge 1.

[0050] The holder 52 has a first outer surface 52A and a second outer surface 52B. The first outer surface 52A is located at one end of the holder 52 in the third direction. The second outer surface 52B is located at the other end of the holder 52 in the third direction. The first outer surface 52A and the second outer surface 52B are spaced apart in the third direction. The second outer surface 52B is movable in the third direction relative to the first outer surface 52A.

[0051] More specifically, the holder 52 of this embodiment has a first holder member 521, a second holder member 522, and a coil spring 523 located therebetween. The first holder member 521 is made of, for example, resin. The second holder member 522 is made of, for example, resin. The first holder member 521 has a first outer surface 52A. The memory 51 is fixed to the first outer surface 52A. Therefore, the electrical contact surface 511 is held by the first outer surface 52A. The second holder member 522 has a second outer surface 52B. The second holder member 522 is movable in a third direction relative to the first holder member 521.

[0052] Coil spring 523 is an elastic member that can expand and contract in the third direction. Coil spring 523 is located between first outer surface 52A and second outer surface 52B in the third direction. One end of coil spring 523 in the third direction is connected to first holder member 521. The other end of coil spring 523 in the third direction is connected to second holder member 522.

[0053] The coil spring 523 expands and contracts in the third direction between a first length and a second length shorter than the first length. When the coil spring 523 is at the second length, the distance in the third direction between the first outer surface 52A and the second outer surface 52B is shorter than the distance in the third direction between the first outer surface 52A and the second outer surface 52B when the coil spring 523 is at the first length. Furthermore, at least the second length is shorter than the natural length of the coil spring 523. When the process cartridge 3 is not attached to the main body frame 90, the length of the coil spring 523 in the third direction is the first length.

[0054] First holder member 521 has first claw 521A and second claw 521B. First claw 521A and second claw 521B each protrude from first holder member 521 in a direction intersecting with the third direction. On the other hand, second holder member 522 has a first claw receiving portion (not shown) and a second claw receiving portion (not shown). The first claw receiving portion and the second claw receiving portion are openings, recesses, or steps.

[0055] When coil spring 523 is at the first length, first claw 521A comes into contact with the first claw receiving portion. Furthermore, when coil spring 523 is at the first length, second claw 521B comes into contact with the second claw receiving portion. This prevents the length of coil spring 523 in the third direction from becoming longer than the first length. Furthermore, first holder member 521 is prevented from being detached from second holder member 522. On the other hand, when coil spring 523 is at the second length, first claw 521A moves away from the first claw receiving portion, and second claw 521B moves away from the second claw receiving portion.

[0056] The second holder member 522 has a first boss 53A, a second boss 53B, and a third boss (not shown). The first boss 53A extends in a first direction from a surface of the second holder member 522 facing the holder cover 47 toward the holder cover 47. Meanwhile, the holder cover 47 has a first hole 47A. The first hole 47A penetrates the holder cover 47 in the first direction. The first boss 53A is inserted into the first hole 47A.

[0057] The second boss 53B and the third boss extend in a first direction from a surface of the second holder member 522 facing the gear cover 45 toward the gear cover 45. Meanwhile, the gear cover 45 has a second hole 45A and a third hole 45B. The second hole 45A and the third hole 45B penetrate the gear cover 45 in the first direction. The second boss 53B is inserted into the second hole 45A. The third boss is inserted into the third hole 45B.

[0058] The size of the first hole 47A in the second direction is larger than the size of the first boss 53A in the second direction. The size of the second hole 45A in the second direction is larger than the size of the second boss 53B in the second direction. Furthermore, the size of the third hole 45B in the second direction is larger than the size of the third boss in the second direction. Therefore, the holder 52, together with the first boss 53A, the second boss 53B, and the third boss, is movable in the second direction relative to the casing 10, the gear cover 45, and the holder cover 47. When the holder 52 moves in the second direction, the memory 51 having the electrical contact surface 511 also moves in the second direction together with the holder 52.

[0059] The size of the first hole 47A in the third direction is larger than the size of the first boss 53A in the third direction. The size of the second hole 45A in the third direction is larger than the size of the second boss 53B in the third direction. Furthermore, the size of the third hole 45B in the third direction is larger than the size of the third boss in the third direction. Therefore, the holder 52, together with the first boss 53A, the second boss 53B, and the third boss, is movable in the third direction relative to the casing 10, the gear cover 45, and the holder cover 47. When the holder 52 moves in the third direction, the memory 51 having the electrical contact surface 511 also moves in the third direction together with the holder 52.

[0060] The holder cover 47 may have a recess, instead of the first hole 47A, into which the first boss 53A can be inserted. The gear cover 45 may have a recess, instead of the second hole 45A, into which the second boss 53B can be inserted. The gear cover 45 may have a recess, instead of the third hole 45B, into which the third boss can be inserted. The holder cover 47 may have a boss, and the second holder member 522 may have a through-hole or recess into which the boss is inserted. The gear cover 45 may have a boss, and the second holder member 522 may have a through-hole or recess into which the boss is inserted.

[0061] That is, either the housing formed by the casing 10, the gear cover 45, and the holder cover 47 or the holder 52 may have a boss, and the other of the housing and the holder 52 may have a through hole or recess into which the boss is inserted.

[0062] <2.2. About the drum cartridge> FIG. 6 is a perspective view of the drum cartridge 2. FIG. 7 is a view of the drum cartridge 2 as viewed from the second end 62 side, which will be described later. As shown in FIGS. 6 and 7, the drum cartridge 2 has a drum frame 60 and a photosensitive drum 70. The developing cartridge 1 is attached to the drum frame 60. The photosensitive drum 70 is rotatable about a second rotation axis extending in the first direction. When the developing cartridge 1 is attached to the drum frame 60, the developing roller 30 comes into contact with the photosensitive drum 70.

[0063] The drum frame 60 has a first end 61 and a second end 62. The first end 61 is located at one end of the drum frame 60 in the first direction. The second end 62 is located at the other end of the drum frame 60 in the first direction. The first end 61 and the second end 62 are spaced apart in the first direction.

[0064] When the developer cartridge 1 is attached to the drum frame 60, the first end surface 11 of the casing 10 is located at the first end 61 of the drum frame 60. When the developer cartridge 1 is attached to the drum frame 60, the second end surface 12 of the casing 10 is located at the second end 62 of the drum frame 60. When the developer cartridge 1 is attached to the drum frame 60, the holder 52 is located farther from the photosensitive drum 70 in the second direction than the first end 61 of the drum frame 60.

[0065] 6, the drum cartridge 2 has a first pressing member 63A and a first spring 64A. The first pressing member 63A and the first spring 64A are located at a first end 61 of the drum frame 60. The first spring 64A is an elastic member that is expandable and contractible in a second direction. The first pressing member 63A is connected to one end of the first spring 64A in the second direction. The other end of the first spring 64A in the second direction is connected to the drum frame 60.

[0066] The drum cartridge 2 also has a second pressing member 63B and a second spring 64B. The second pressing member 63B and the second spring 64B are located at the second end 62 of the drum frame 60. The second spring 64B is an elastic member that is expandable and contractible in the second direction. The second pressing member 63B is connected to one end of the second spring 64B in the second direction. The other end of the second spring 64B in the second direction is connected to the drum frame 60.

[0067] When the developer cartridge 1 is attached to the drum frame 60, the first pressing member 63A comes into contact with one end of the developer cartridge 1 in the first direction. This causes the first spring 64A to contract. Then, due to the elastic repulsive force of the first spring 64A, the first pressing member 63A presses the one end of the developer cartridge 1 in the first direction toward the photosensitive drum 70. Furthermore, when the developer cartridge 1 is attached to the drum frame 60, the second pressing member 63B comes into contact with the other end of the developer cartridge 1 in the first direction. This causes the second spring 64B to contract. Then, due to the elastic repulsive force of the second spring 64B, the second pressing member 63B presses the other end of the developer cartridge 1 in the first direction toward the photosensitive drum 70. As a result, the developing roller 30 comes into contact with the photosensitive drum 70.

[0068] 6, the drum frame 60 has two protrusions 65. The two protrusions 65 are aligned at a distance from each other in the first direction. When the developer cartridge 1 is attached to the drum frame 60, the two protrusions 65 protrude from the surface of the drum frame 60 toward the casing 10. The surface of each protrusion 65 is a curved surface that curves convexly toward the casing 10.

[0069] When the developer cartridge 1 is attached to the drum frame 60, the two protrusions 65 come into contact with the casing 10. This stabilizes the position of the casing 10 relative to the drum frame 60. The number of protrusions 65 on the drum frame 60 may be one, or three or more.

[0070] <3. Holder guide> 8 and 9 are partial perspective views of the main body frame 90. As shown in FIGS. 8 and 9, the main body frame 90 has four holder guides 80. The main body frame 90 has a holder guide 80 for each slot 91. That is, the main body frame 90 has one holder guide 80 for each slot 91. The four holder guides 80 are located at one end of the main body frame 90 in the first direction. Each holder guide 80 extends in the second direction.

[0071] Fig. 10 is a partial cross-sectional view of the main body frame 90. Fig. 10 shows a cross section perpendicular to the first direction and including the holder guide 80. As shown in Fig. 10, the holder guide 80 has a first guide surface 81 and a second guide surface 82.

[0072] The first guide surface 81 is a surface that comes into contact with and guides the first outer surface 52A of the holder 52 when the process cartridge 3 is attached to the main body frame 90. The second guide surface 82 is a surface that comes into contact with and guides the second outer surface 52B of the holder 52 when the process cartridge 3 is attached to the main body frame 90. The first guide surface 81 and the second guide surface 82 each extend in the second direction.

[0073] The first guide surface 81 and the second guide surface 82 face each other with a gap therebetween in the third direction. The distance in the third direction between the first guide surface 81 and the second guide surface 82 is shorter than the distance in the third direction between the first outer surface 52A and the second outer surface 52B when the coil spring 523 of the holder 52 has the first length.

[0074] The image forming apparatus 100 also has an electrical contact 83. The electrical contact 83 is a terminal that comes into contact with the electrical contact surface 511 of the memory 51 when the process cartridge 3 is attached to the main body frame 90. The electrical contact 83 is located on the first guide surface 81. More specifically, the electrical contact 83 protrudes in the third direction from the first guide surface 81 toward the second guide surface 82. The electrical contact 83 and the second guide surface 82 face each other with a gap in the third direction. The electrical contact 83 is made of metal, which is a conductor. The electrical contact 83 is electrically connected to the control unit 92.

[0075] The image forming apparatus 100 also has a transfer belt 84 and four transfer rollers 85. As indicated by the dashed lines in Fig. 10, the transfer belt 84 and the transfer rollers 85 are located at the end of the slot 91 opposite the insertion opening. The image forming apparatus 100 has a transfer roller 85 for each slot 91.

[0076] When the process cartridge 3 is installed in the slot 91, the outer peripheral surface of the photosensitive drum 70 comes into contact with the transfer belt 84. The transfer belt 84 is then sandwiched between the photosensitive drum 70 and the transfer roller 85. The printing paper passes between the photosensitive drum 70 and the transfer belt 84. At this time, the image forming apparatus 100 supplies a transfer bias to the transfer roller 85. As a result, the developer carried on the outer surface of the photosensitive drum 70 is transferred to the printing paper.

[0077] The holder guide 80 is located closer to the insertion opening of the slot 91 than the transfer belt 84 in the second direction.

[0078] FIG. 11 is a cross-sectional view of the image forming apparatus 100 when the developer cartridge 1 is attached to the main body frame 90. FIG. 11 shows a cross section perpendicular to the first direction and including the holder 52. As shown in FIG. 11, when the process cartridge 3 is attached to the slot 91 of the main body frame 90, the holder 52 is inserted between the first guide surface 81 and the second guide surface 82. The first outer surface 52A moves in the second direction along the first guide surface 81 toward the transfer belt 84. The second outer surface 52B moves in the second direction along the second guide surface 82 toward the transfer belt 84.

[0079] At this time, the first outer surface 52A approaches the second outer surface 52B in the third direction, and the second outer surface 52B approaches the first outer surface 52A in the third direction. More specifically, the first outer surface 52A moves toward the second outer surface 52B in the third direction relative to the drum frame 60. Furthermore, the second outer surface 52B moves toward the first outer surface 52A in the third direction relative to the drum frame 60. As a result, the length of the coil spring 523 in the third direction is shortened from the first length to the second length.

[0080] FIG. 12 is a cross-sectional view of the image forming apparatus 100 with the developer cartridge 1 attached to the main body frame 90. FIG. 12 shows a cross section perpendicular to the first direction and including the holder 52. As shown in FIG. 12, when the process cartridge 3 is completely attached to the slot 91, the electrical contact surface 511 of the memory 51 comes into contact with the electrical contact 83. This electrically connects the electrical contact surface 511 and the electrical contact 83. Therefore, the control unit 92 can perform at least one of reading information from the memory 51 and writing information to the memory 51.

[0081] When electrical contact surface 511 of memory 51 is in contact with electrical contact 83, the length of coil spring 523 in the third direction becomes the second length. Therefore, the elastic repulsive force of coil spring 523 presses electrical contact surface 511 toward electrical contact 83. This stabilizes the contact state between electrical contact surface 511 and electrical contact 83.

[0082] As described above, in the structure of this embodiment, the second outer surface 52B of the holder 52 contacts the second guide surface 82 of the main body frame 90, not the drum frame 60. Therefore, there is no need to provide the drum frame 60 with a surface for supporting the second outer surface 52B. This allows the drum cartridge 2 to be made smaller.

[0083] In particular, the image forming apparatus 100 of this embodiment includes four process cartridges 3. Therefore, the above-described structure allows each of the four drum cartridges 2 to be made smaller, thereby enabling the image forming apparatus 100 to be made even more compact.

[0084] Furthermore, the holder guide 80 of this embodiment has a surface 86. The surface 86 is located between the second guide surface 82 and the transfer belt 84 in the second direction. The surface 86 extends in a direction intersecting the second direction. When the process cartridge 3 is installed in the slot 91 of the main body frame 90, the surface 86 faces the holder 52 in the second direction. More specifically, the surface 86 faces a portion including the second outer surface 52B of the second holder member 522 in the second direction.

[0085] With the process cartridge 3 attached to the main body frame 90, if the second outer surface 52B of the holder 52 attempts to move toward the transfer belt 84 from its normal position, the second holder member 522 comes into contact with the surface 86. This limits the range within which the second holder member 522 can move in the second direction toward the transfer belt 84. This prevents the holder 52 from tilting. As a result, the contact state between the electrical contact surface 511 and the electrical contact 83 can be made more stable.

[0086] However, when the process cartridge 3 is attached to the main body frame 90 and the electrical contact surface 511 is in contact with the electrical contact 83, the surface 86 moves away from the holder 52 in the second direction. This prevents the surface 86 from excessively restricting the movement of the holder 52.

[0087] <4. Separation operation> After the process cartridge 3 is mounted in the main body frame 90, the image forming apparatus 100 can perform a separation operation. The separation operation is an operation for temporarily separating the developing roller 30 from the photosensitive drum 70. In other words, the separation operation is an operation for moving the casing 10 from a contact position where the developing roller 30 contacts the photosensitive drum 70 to a separation position where the developing roller 30 is separated from the photosensitive drum 70.

[0088] For example, when performing monochrome printing, the image forming apparatus 100 performs the separation operation for the process cartridges 3 of each color other than black. However, the image forming apparatus 100 may also perform the separation operation for the black process cartridge 3.

[0089] 13 and 14 are perspective views of the process cartridge 3 when the separating operation is performed.

[0090] As shown in FIG. 13, the developer cartridge 1 has a developer separation lever 15. The developer separation lever 15 is located on the second end surface 12 of the casing 10. The developer separation lever 15 is movable relative to the casing 10. The developer separation lever 15 also has a shaft (not shown). The shaft extends from the developer separation lever 15 in a first direction. When the developer cartridge 1 is attached to the drum cartridge 2, the shaft of the developer separation lever 15 comes into contact with the drum frame 60. The developer separation lever 15 is then able to rotate about the shaft while in contact with the drum frame 60.

[0091] The image forming apparatus 100 has a first main body cam 93. When performing a separation operation, the image forming apparatus 100 operates the first main body cam 93. This causes the first main body cam 93 to come into contact with one end of the developer separation lever 15. Then, the first main body cam 93 presses the one end of the developer separation lever 15 in the second direction toward the photosensitive drum 70.

[0092] As a result, the developer separating lever 15 rotates about the shaft supported by the drum frame 60. As a result, the other end of the developer separating lever 15 comes into contact with the casing 10. Then, the other end of the developer separating lever 15 presses the casing 10 in the second direction, in a direction away from the photosensitive drum 70. As a result, the first end surface 11 of the casing 10 moves in a direction away from the photosensitive drum 70.

[0093] 14, the drum cartridge 2 also has a drum spacing lever 66. The drum spacing lever 66 is located at the first end 61 of the drum frame 60. The drum spacing lever 66 is rotatable about a drum axis extending in the first direction. When the casing 10 is located at the contact position, the drum spacing lever 66 is spaced apart from the casing 10.

[0094] The image forming apparatus 100 has a second main body cam 94. When performing a separation operation, the image forming apparatus 100 operates the second main body cam 94. This causes the second main body cam 94 to come into contact with one end of the drum separation lever 66. The second main body cam 94 then presses the one end of the drum separation lever 66 in the second direction toward the photosensitive drum 70.

[0095] As a result, the drum separation lever 66 rotates about the drum shaft. As a result, the other end of the drum separation lever 66 comes into contact with the casing 10. The other end of the drum separation lever 66 then presses the casing 10 in the second direction, away from the photosensitive drum 70. As a result, the second end surface 12 of the casing 10 moves in the direction away from the photosensitive drum 70.

[0096] In this way, at one end of the main body frame 90 in the first direction, the first main body cam 93 presses the developer separation lever 15, and the developer separation lever 15 presses the casing 10 in a direction away from the photosensitive drum 70. At the other end of the main body frame 90 in the first direction, the second main body cam 94 presses the drum separation lever 66, and the drum separation lever 66 presses the casing 10 in a direction away from the photosensitive drum 70. This allows the casing 10 to move from a contact position where the developing roller 30 contacts the photosensitive drum 70 to a separation position where the developing roller 30 is separated from the photosensitive drum 70.

[0097] FIG. 15 is a cross-sectional view of image forming apparatus 100 when the separation operation is performed. FIG. 15 shows a cross section perpendicular to the first direction and including holder 52. The position of holder 52 relative to main body frame 90 does not change between when the separation operation is not performed as in FIG. 12 and when the separation operation is performed as in FIG. 15. Therefore, with electrical contact surface 511 of memory 51 in contact with electrical contact 83 and second outer surface 52B of holder 52 in contact with second guide surface 82, casing 10 moves in the second direction between the contact position and the separation position relative to main body frame 90 and holder 52. This prevents the electrical contact surface 511 from rubbing against electrical contact 83.

[0098] Furthermore, during the separation operation, the operation of the drum separation lever 66 applies pressure to the drum frame 60. This may cause the drum frame 60 to deform or vibrate slightly. However, the second outer surface 52B of the holder 52 is supported by the second guide surface 82 of the main body frame 90, not the drum frame 60. Therefore, even if the operation of the drum separation lever 66 causes the drum frame 60 to deform or vibrate, the position of the holder 52 relative to the main body frame 90 is unlikely to change. This further reduces friction of the electrical contact surface 511 against the electrical contact 83.

[0099] Furthermore, when the casing 10 moves between the contact position and the separated position, the casing 10 moves in the second direction while contacting the two protrusions 65. This prevents the casing 10 from tilting, allowing the casing 10 to move smoothly along the protrusions 65. Furthermore, since vibration of the casing 10 can be suppressed, rubbing of the electrical contact surface 511 against the electrical contact 83 can be further suppressed.

[0100] In particular, the surfaces of the two protrusions 65 are curved. This allows the casing 10 to move more smoothly along the two protrusions 65. Therefore, vibration of the casing 10 during the separation operation can be further suppressed.

[0101] <5. Variations> Although one embodiment of the present disclosure has been described above, the present disclosure is not limited to the above embodiment.

[0102] In the above embodiment, the holder 52 has the coil spring 523 as the elastic member. However, instead of the coil spring 523, the holder 52 may have another type of elastic member, such as a leaf spring or a torsion spring.

[0103] In the above embodiment, the memory 51 having the electrical contact surface 511 is held on the outer surface of the holder 52. However, only the electrical contact surface 511 may be held on the outer surface of the holder 52, and the portion of the memory 51 other than the electrical contact surface 511 may be located elsewhere in the developing cartridge 1.

[0104] 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]

[0105] 1 Developer cartridge 2 drum cartridges 3 Process cartridge 10 Casing 20 Agitator 30 Developing roller 40 Gear section 50 Memory Assembly 51 memory 52 Holder 52A 1st outer surface 52B 2nd outer surface 60 Drum Frame 65 Protrusion 66 Drum separation lever 70 Photosensitive drum 80 Holder guide 81 First guide surface 82 Second guide surface 83 Electrical Contacts 86 sides 90 Main frame 100 Image forming device 511 Electrical Contact Surface 523 Coil spring

Claims

1. An image forming apparatus capable of mounting a developing cartridge mounted in a drum cartridge, The developing cartridge is a developing roller rotatable about a first rotation axis extending in a first direction; a housing capable of accommodating a developer, the developing roller being located at one end of the housing in the second direction; a storage medium having an electrical contact surface; a holder located at one end of the housing in the first direction and holding the electrical contact surface, a first outer surface located at one end of the holder in a third direction intersecting the electrical contact surface, the first outer surface supporting the electrical contact surface; a second outer surface located at the other end of the holder in the third direction and spaced apart from the first outer surface in the third direction; an elastic member positioned between the first outer surface and the second outer surface and stretchable in the third direction; a holder having Equipped with The drum cartridge is a photosensitive drum rotatable about a second rotation axis extending in the first direction; Equipped with the image forming apparatus, an electrical contact that can come into contact with the electrical contact surface; a main body frame to which the developing cartridge is attached in a state in which the developing cartridge is attached to the drum cartridge; Equipped with The main body frame is A holder guide extending in the second direction, a first guide surface that guides the first outer surface when the developing cartridge is attached to the main body frame, the first guide surface being on which the electrical contact is located; a second guide surface that guides the second outer surface when the developing cartridge is attached to the main body frame; holder guide including and an image forming apparatus characterized in that, when the electrical contact surface is in contact with the electrical contact and the second outer surface is in contact with the second guide surface, the housing is movable in the second direction relative to the holder between a contact position where the developing roller is in contact with the photosensitive drum and a separation position where the developing roller is separated from the photosensitive drum.

2. 2. The image forming apparatus according to claim 1, The holder is a first holder member having the first outer surface; a second holder member having the second outer surface; and The image forming apparatus, wherein the second holder member is movable in the third direction relative to the first holder member.

3. 3. The image forming apparatus according to claim 1, The holder guide is a surface facing the holder in the second direction when the developing cartridge is attached to the main body frame; An image forming apparatus further comprising:

4. 4. The image forming apparatus according to claim 3, an image forming apparatus, wherein the surface is spaced apart from the holder in the second direction when the developing cartridge is attached to the main body frame;

5. 5. The image forming apparatus according to claim 1, When the developing cartridge is attached to the main body frame, the first outer surface approaches the second outer surface in the third direction; The image forming apparatus, wherein the second outer surface approaches the first outer surface in the third direction.

6. 6. The image forming apparatus according to claim 5, When the developing cartridge is not attached to the main body frame, the length of the elastic member in the third direction is a first length, When the developing cartridge is attached to the main body frame, The image forming apparatus is characterized in that the length of the elastic member in the third direction is a second length that is shorter than the first length.

7. 7. The image forming apparatus according to claim 1, The drum cartridge is a drum spacing lever rotatable about a drum shaft extending in the first direction; and When the housing is located at the contact position, the drum separation lever is separated from the housing, When the housing is located at the separated position, the drum separating lever presses the housing.

8. 8. The image forming apparatus according to claim 1, The drum cartridge is a pressing member that presses the developing cartridge toward the photosensitive drum when the developing cartridge is attached to the drum cartridge; An image forming apparatus further comprising:

9. 9. The image forming apparatus according to claim 1, The drum cartridge is A protrusion that comes into contact with the housing when the developing cartridge is attached to the drum cartridge. and The image forming apparatus, wherein the housing comes into contact with the protrusion when the housing moves between the contact position and the separated position.

10. 10. The image forming apparatus according to claim 9, The image forming apparatus is characterized in that the protrusion has a curved surface.

11. 11. The image forming apparatus according to claim 1, An image forming apparatus comprising a plurality of the developing cartridges attached to the drum cartridge.

Images