WO2019064642A1

WO2019064642A1 - Developer cartridge

Info

Publication number: WO2019064642A1
Application number: PCT/JP2018/011010
Authority: WO
Inventors: 板橋　奈緒
Original assignee: ブラザー工業株式会社
Priority date: 2017-09-29
Filing date: 2018-03-20
Publication date: 2019-04-04
Also published as: JP2022093549A; JP7428206B2; JP2019066577A

Abstract

A developer cartridge structure is provided which allows positioning a developer roller without using the shaft of the developer roller. This developer cartridge has a housing that can house a developer. The housing has a first end and a second end in a first direction. Further, the housing has a first rotation shaft part 63. In the first direction, the first rotation shaft part 63 is located further away from an agitator shaft than a developer roller 30. Further, the first rotation shaft part 63 extends in a second direction. The developer roller, the agitator and the housing can rotate about the first rotation shaft part 63. By means of this structure, it is possible to position the developer roller using not the shaft of the developer roller 30, but the first rotation shaft part 63, which is separate from the developer roller 30.

Description

Developer cartridge

The present disclosure relates to a developing cartridge.

2. Description of the Related Art Conventionally, electrophotographic image forming apparatuses such as laser printers and LED printers are known. A developing cartridge is used in the image forming apparatus. The developing cartridge has a developing roller. A conventional developing cartridge is described in, for example, Patent Document 1. The developing cartridge of Patent Document 1 is mounted on a drum unit (process frame). The drum unit has a photosensitive drum. When the developing cartridge is inserted into the drum unit, the photosensitive drum and the developing roller face each other. Then, the drum unit on which the developing cartridge is mounted is accommodated inside the image forming apparatus.

JP 2011-59510 A

When the developing cartridge is mounted on the drum unit, the developing cartridge is positioned on the frame of the drum unit by the shaft of the developing roller. Thereby, the developing roller is positioned with respect to the photosensitive drum.

An object of the present invention is to provide a structure in which the developing roller can be positioned in the developing cartridge without using the shaft of the developing roller.

In order to solve the above-mentioned subject, the 1st invention of this application is a case which can store a developer, and the case which has one end and the other end in the 1st direction, and can stir the developer An agitator having an agitator shaft extending in a second direction, and a developing roller positioned closer to the one end than the agitator shaft in the first direction, the rotational axis extending in the second direction A developing cartridge comprising: a rotatable developing roller; and a first rotation shaft portion which is spaced apart from the agitator shaft in the first direction and is spaced apart from the agitator shaft in the first direction, and extends in the second direction. The roller, the agitator, and the housing may be pivotable about the first pivot shaft.

A second invention of the present application is the developing cartridge of the first invention, wherein a distance between the developing roller and the first rotation shaft portion in the first direction is a fixed distance.

A third invention of the present application is the developing cartridge of the first invention or the second invention, wherein the diameter of the first rotation shaft portion is smaller than the diameter of the outer peripheral surface of the developing roller.

A fourth invention of the present application is the developing cartridge according to any one of the first invention to the third invention, wherein the first rotating shaft portion is separated from the developing roller by a first distance in the first direction, The developing cartridge further includes a pressing receiving surface separated by a specific distance greater than the first distance from the first rotation shaft in the first direction, and the pressing receiving surface receives the pressing force. The developing roller, the agitator, and the casing rotate around the first rotation shaft.

A fifth invention of the present application is the developing cartridge of the fourth invention, wherein the pressing receiving surface is positioned closer to the other end than the developing roller in the first direction.

A sixth invention of the present application is the developing cartridge according to any one of the first invention to the fifth invention, wherein the first rotation shaft portion is a first roller, and the first roller is the second roller. It is characterized in that it is rotatable about an axis of rotation extending in a direction.

A seventh invention of the present application is the developing cartridge according to any one of the first invention to the sixth invention, wherein the developing cartridge is mounted on a drum unit having a photosensitive drum rotatable about a rotating shaft extending in the second direction. It is possible that the developing roller, the agitator, and the casing are rotatable with respect to the drum unit around the first rotation shaft.

An eighth invention of the present application is the developing cartridge of the seventh invention, wherein the first rotation shaft portion has a first curved surface, and the first rotating shaft portion is mounted on the drum unit when the developing cartridge is mounted on the drum unit. The developing roller, the agitator, and the housing rotate with respect to the drum unit around the first rotation shaft in a state where the curved surface is in contact with the frame of the drum unit. .

A ninth invention of the present application is the developing cartridge according to the seventh invention or the eighth invention, wherein the developing roller, the agitator, and the casing are the first when the developing cartridge is mounted on the drum unit. An outer peripheral surface of the developing roller is in contact with an outer peripheral surface of the photosensitive drum when rotating with respect to the drum unit around a rotating shaft portion.

A tenth invention of the present application is the developing cartridge according to any one of the first invention to the sixth invention, wherein the developing cartridge is mounted on a drum unit having a photosensitive drum rotatable about a rotating shaft extending in the second direction. It is possible that, when the developing cartridge is mounted on the drum unit, the developing roller, the agitator, and the housing are the first rotation shaft after the pressing receiving surface receives the pressing force. The outer circumferential surface of the developing roller is in contact with the outer circumferential surface of the photosensitive drum when the drum unit rotates about the drum unit with respect to the drum unit.

An eleventh invention of the present application is the developing cartridge of the tenth invention, wherein the developing roller, the agitator, and the housing are the first after the first rotation shaft portion contacts the frame of the drum unit. An outer peripheral surface of the developing roller is in contact with an outer peripheral surface of the photosensitive drum when rotating with respect to the drum unit around a rotating shaft portion.

A twelfth invention of the present application is the developing cartridge of the eleventh invention, wherein the first rotation shaft portion has a first curved surface, and the first curved surface contacts the frame of the drum unit. When the developing roller, the agitator, and the housing rotate with respect to the drum unit around the first rotation shaft, an outer peripheral surface of the developing roller contacts an outer peripheral surface of the photosensitive drum. I assume.

A thirteenth invention of the present application is the developing cartridge according to any one of the tenth invention to the twelfth invention, further comprising a receiving surface which receives a separation force in a direction of separating the developing roller from the photosensitive drum. Do.

A fourteenth invention of the present application is the developing cartridge according to any one of the first invention to the thirteenth invention, wherein the housing includes the first pivot shaft portion.

A fifteenth invention of the present application is the developing cartridge of the first invention, wherein the first rotation shaft portion is located at one end of the housing in the second direction, and the developing cartridge is in the first direction. A second pivoting shaft portion which is located farther from the agitator shaft than the developing roller and extends in the second direction, and which is located away from the first pivoting shaft portion in the second direction. The apparatus further comprises a pivot shaft, and the developing roller, the agitator, and the housing pivot about the first pivot shaft and the second pivot shaft.

A sixteenth invention of the present application is the developing cartridge according to the fifteenth invention, wherein a distance between the developing roller and the first rotation shaft in the first direction is a fixed distance, and the developing roller in the first direction is the same. The distance between the second pivot shaft portion and the second pivot shaft portion is a constant distance.

A seventeenth invention of the present application is the developing cartridge of the fifteenth invention or the sixteenth invention, wherein the diameter of the first rotation shaft portion is smaller than the diameter of the outer peripheral surface of the developing roller, and the second rotation shaft The diameter of the portion is smaller than the diameter of the outer peripheral surface of the developing roller.

An eighteenth invention of the present application is the developing cartridge according to any one of the fifteenth to seventeenth inventions, wherein the first rotating shaft portion is separated from the developing roller by a first distance in the first direction, The second pivot shaft portion is separated by a second distance from the developing roller in the first direction, and the developing cartridge is further configured to pivot the first pivot shaft portion and the second pivot shaft in the first direction. The pressure receiving surface is separated from the shaft by a specific distance greater than the first distance and the second distance, and when the pressure receiving surface receives a pressing force, the developing roller, the agitator, and the housing It is characterized in that it pivots about a first pivoting shaft portion and the second pivoting shaft portion.

A nineteenth invention of the present application is the developing cartridge of the eighteenth invention, wherein the pressing receiving surface is positioned closer to the other end than the developing roller in the first direction.

A twentieth invention of the present application is the developing cartridge according to any one of the fifteenth to nineteenth inventions, wherein the first rotation shaft portion is a first roller, and the second rotation shaft portion is A second roller, wherein the first roller is rotatable about a rotational axis extending in the second direction, and the second roller is rotatable about an rotational axis extending in the second direction. .

A twenty-first invention of the present application is the developing cartridge according to any one of the fifteenth invention to the twentieth invention, wherein the developing cartridge is mounted on a drum unit having a photosensitive drum rotatable about a rotating shaft extending in the second direction. It is possible that the developing roller, the agitator, and the casing are rotatable with respect to the drum unit around the first and second rotating shaft portions. .

The twenty-second invention of the present application is the developing cartridge of the twenty-first invention, wherein the first rotation shaft portion has a first curved surface, and the second rotation shaft portion has a second curved surface. When the developing cartridge is mounted on the drum unit, the developing roller, the agitator, and the housing are in a state in which the first curved surface and the second curved surface are in contact with the frame of the drum unit. It rotates with respect to the said drum unit centering on a said 1st rotational axis part and a said 2nd rotational axis part.

A twenty-third invention of the present application is the developing cartridge according to the twenty-first invention or the twenty-second invention, wherein the developing roller, the agitator, and the casing are the first when the developing cartridge is mounted on the drum unit. An outer peripheral surface of the developing roller is in contact with an outer peripheral surface of the photosensitive drum when rotating with respect to the drum unit around a rotating shaft portion and the second rotating shaft portion.

A twenty-fourth invention of the present application is the developing cartridge according to any one of the fifteenth to nineteenth inventions, wherein the developing cartridge is mounted on a drum unit having a photosensitive drum rotatable about a rotation axis extending in the second direction. It is possible that, when the developing cartridge is mounted on the drum unit, the developing roller, the agitator, and the housing are the first rotation shaft after the pressing receiving surface receives the pressing force. And when it rotates with respect to the said drum unit centering on a said 2nd rotational axis part, it is characterized by the outer peripheral surface of the said developing roller contacting the outer peripheral surface of the said photosensitive drum.

A twenty-fifth invention of the present application is the developing cartridge according to the twenty-fourth invention, wherein the developing roller, the agitator, and the developing roller are provided after the first and second rotating shaft portions come in contact with the frame of the drum unit. The outer peripheral surface of the developing roller contacts the outer peripheral surface of the photosensitive drum when the housing rotates with respect to the drum unit around the first rotating shaft and the second rotating shaft. It features.

The twenty-sixth invention of the present application is the developing cartridge of the twenty-fifth invention, wherein the first rotation shaft portion has a first curved surface, and the second rotation shaft portion has a second curved surface. After the first curved surface and the second curved surface come in contact with the frame of the drum unit, the developing roller, the agitator, and the housing, the first rotation shaft portion and the second rotation shaft portion The outer peripheral surface of the developing roller is in contact with the outer peripheral surface of the photosensitive drum when it is rotated with respect to the drum unit with the center as a center.

The twenty-seventh invention of the present application is the developing cartridge according to any one of the twenty-fourth to twenty-sixth inventions, further comprising a receiving surface which receives a separation force in a direction to separate the developing roller from the photosensitive drum. Do.

A twenty-eighth invention of the present application is the developing cartridge according to any one of the fifteenth to twenty-seventh inventions, wherein the housing includes the first pivot shaft portion and the second pivot shaft portion. It features.

The 29th invention of the present application is the developing cartridge according to any one of the 7th to 13th inventions or the 21st to 27th inventions, wherein the developing roller extends in a second direction along the rotation axis. A roller shaft is provided, and the developing roller shaft and the drum unit are not in contact with each other.

According to the first to twenty-ninth aspects of the present invention, the developing roller can be positioned using not the shaft of the developing roller but the first pivoting shaft portion different from the developing roller.

According to the fourth and fifth aspects of the invention, the pressing force received by the pressing receiving surface is amplified by the lever principle and transmitted to the developing roller.

Further, according to the fifteenth invention through the twenty-eighth invention, the developing roller can be positioned using the first rotation shaft and the second rotation shaft separated from the first rotation shaft in the second direction. . Thereby, the developing roller can be positioned more accurately.

1st Embodiment: It is a perspective view of a developing cartridge and a drum unit. First embodiment: a partial exploded perspective view of a developing cartridge. 1st Embodiment: It is the figure which showed a mode when mounting | wearing with a developing cartridge. 1st Embodiment: It is the figure which showed a mode when mounting | wearing with a developing cartridge. 1st Embodiment: It is the figure which showed a mode when mounting | wearing with a developing cartridge. 1st embodiment: It is a figure showing the situation at the time of separation operation. Second Embodiment: It is a partial perspective view of a developing cartridge.

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

Hereinafter, the direction in which the agitator and the developing roller are arranged will be referred to as a "first direction". Further, the direction in which the rotation shaft of the developing roller extends is referred to as a "second direction". The first direction and the second direction intersect (preferably are orthogonal to) each other. The structure of the drum unit will also be described using the “first direction” and the “second direction” in the state where the developing cartridge is mounted on the drum unit.

<1. First embodiment>
<1-1. Structure of developing cartridge and drum unit>
FIG. 1 is a perspective view of the developing cartridge 1 and the drum unit 9 according to the first embodiment. The developing cartridge 1 and the drum unit 9 are used in an electrophotographic image forming apparatus. Examples of the image forming apparatus include a laser printer and an LED printer. The drum unit 9 is removable from the image forming apparatus. That is, the drum unit 9 is a replaceable cartridge. As shown in FIG. 1, the frame 90 of the drum unit 9 has four cartridge holding portions 91. The drum unit 9 also has a photosensitive drum 92 for each of the cartridge holding portions 91. Each photosensitive drum 92 is rotatable about a rotational axis extending in the second direction. Each photosensitive drum 92 has a cylindrical outer peripheral surface centered on the rotation axis.

The developing cartridge 1 is attachable to and detachable from the cartridge holding unit 91. In the present embodiment, four developing cartridges 1 are attached to one drum unit 9. The four developing cartridges 1 contain developers of different colors (for example, cyan, magenta, yellow, and black). An example of the developer is toner. However, the number of developing cartridges 1 mounted to the drum unit 9 may be one to three, or five or more.

FIG. 2 is a partially exploded perspective view of the developing cartridge 1. As shown in FIGS. 1 and 2, the developing cartridge 1 has a casing 10, an agitator 20, a developing roller 30, a gear portion 40, a gear cover 50, and a bearing plate 60.

The casing 10 is a housing capable of containing a developer. The casing 10 has a first outer surface 11 and a second outer surface 12. The first outer surface 11 is located at one end of the casing 10 in the second direction. The second outer surface 12 is located at the other end of the casing 10 in the second direction. The casing 10 extends in a second direction between the first outer surface 11 and the second outer surface 12. The gear portion 40, the gear cover 50, and the bearing plate 60 are located on the first outer surface 11. Further, inside the casing 10, a storage chamber 13 is provided. The developer is stored in the storage chamber 13.

The casing 10 also has one end 15 and the other end 16 in the first direction. An opening 14 is provided in the vicinity of one end 15 of the casing 10. The storage chamber 13 and the outside communicate with each other through the opening 14.

The agitator 20 has an agitator shaft 21 and an agitation blade 22. The agitator shaft 21 is rotatable about a rotational axis extending in the second direction. The stirring blade 22 spreads radially outward from the agitator shaft 21. At least a part of the agitator shaft 21 and the stirring blade 22 are located in the storage chamber 13. One end of the agitator shaft 21 in the second direction is fixed to the agitator gear 42 included in the gear portion 40 so as not to be relatively rotatable. Therefore, the agitator shaft 21 and the stirring blade 22 rotate with the agitator gear 42. When the stirring blade 22 rotates, the developer in the storage chamber 13 is stirred.

The developing roller 30 is a roller that is rotatable about a rotation axis extending in the second direction. The developing roller 30 is located at the opening 14 of the casing 10. That is, the developing roller 30 is positioned closer to the one end 15 than the agitator shaft 21 in the first direction. When the developing cartridge 1 is attached to the cartridge holding portion 91 of the drum unit 9, the outer peripheral surface of the developing roller 30 contacts the outer peripheral surface of the photosensitive drum 92.

The developing roller 30 of the present 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 the second direction. As a material of the developing roller main body 31, for example, rubber having elasticity is used. The developing roller shaft 32 is a cylindrical member penetrating the developing roller main body 31 in the second direction. For the material of the developing roller shaft 32, metal or resin having conductivity is used. The developing roller main body 31 is fixed to the developing roller shaft 32 so as not to be relatively rotatable.

The developing roller gear 43 included in the gear portion 40 is attached to one end of the developing roller shaft 32 in the second direction. More specifically, one end of the developing roller shaft 32 in the second direction is fixed to the developing roller gear 43 so as not to be relatively rotatable. Therefore, when the developing roller gear 43 rotates, the developing roller shaft 32 also rotates, and the developing roller main body 31 also rotates with the developing roller shaft 32.

The developing roller shaft 32 may not penetrate through the developing roller main body 31 in the second direction. For example, the pair of developing roller shafts 32 may extend in the first direction from both ends of the developing roller main body 31 in the second direction. Specifically, the developing roller shaft 32 may be bonded or welded as separate parts to both ends of the developing roller main body 31 in the second direction.

Further, the developing cartridge 1 has a supply roller whose illustration is omitted. The supply roller is located between the developing roller 30 and the agitator 20. Also, the supply roller is rotatable about a rotation axis extending in the second direction. When the developing cartridge 1 receives the driving force, the developer is supplied from the storage chamber 13 in the casing 10 to the outer peripheral surface of the developing roller 30 through the supply roller. At this time, the developer is frictionally charged between the supply roller and the developing roller 30. On the other hand, a bias voltage is applied to the developing roller shaft 32 of the developing roller 30. For this reason, the developer is attracted to the outer peripheral surface of the developing roller main body 31 by the electrostatic force between the developing roller shaft 32 and the developer.

Further, the developing cartridge 1 has a layer thickness regulating blade whose illustration is omitted. The layer thickness regulating blade shapes the developer supplied to the outer peripheral surface of the developing roller main body 31 into a constant thickness. Thereafter, the developer on the outer peripheral surface of the developing roller main body 31 is supplied to the photosensitive drum 92 of the drum unit 9. 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 peripheral surface of the photosensitive drum 92. Thereby, the electrostatic latent image is visualized on the outer peripheral surface of the photosensitive drum 92.

The gear portion 40 is located on the first outer surface 11 of the casing 10. The gear portion 40 has a plurality of gears including the agitator gear 42 and the developing roller gear 43 described above, and a coupling 41. The coupling 41 has a fastening hole 411. When the drum unit 9 to which the developing cartridge 1 is mounted is stored in the image forming apparatus, the drive shaft of the image forming apparatus is inserted into the fastening hole 411 of the coupling 41. Then, the rotation of the drive shaft is transmitted to the plurality of gears including the agitator gear 42 and the developing roller gear 43 through the coupling 41.

In FIG. 2, illustration of the teeth of each gear included in the gear portion 40 is omitted. The plurality of gears included in the gear portion 40 may transmit rotational force by meshing of teeth, or may transmit rotational force by friction. For example, the plurality of gears may have an outer circumferential surface made of rubber instead of the teeth.

The gear cover 50 is fixed to the first outer surface 11 of the casing 10, for example, by screwing. The gear cover 50, together with the casing 10 and the bearing plate 60, constitutes a part of the housing of the developing cartridge 1. At least a portion of the plurality of gears of the gear unit 40 is covered by a gear cover 50. The outer surface of the gear cover 50 has an extending portion 51 extending in the second direction. A circular hole 52 is provided at the tip of the extension 51. The coupling 41 fits in the circular hole 52. Therefore, the fastening hole 411 of the coupling 41 is exposed to the outside from the gear cover 50.

The bearing plate 60 is located between the casing 10 and the gear cover 50 in the second direction. The bearing plate 60 constitutes a part of the housing of the developing cartridge 1 together with the casing 10 and the gear cover 50. The coupling 41 and the developing roller gear 43 described above are located between the bearing plate 60 and the gear cover 50. The agitator gear 42 described above is located between the casing 10 and the bearing plate 60. The bearing plate 60 has a flat portion 61, a bearing protrusion 62, and a first pivoting shaft portion 63. The flat portion 61 spreads perpendicularly to the second direction. The bearing projection 62 projects in the second direction from the flat plate portion 61 toward the gear cover 50. The coupling 41 rotates while being supported by the bearing projection 62.

The housing of the developing cartridge 1 has a first rotation shaft 63 at one end in the second direction. In detail, the first rotation shaft 63 is located at one end of the bearing plate 60 in the first direction. Further, the first rotation shaft portion 63 is positioned farther from the agitator shaft 21 than the developing roller 30 in the first direction. The first pivot shaft portion 63 protrudes from the flat plate portion 61 in the second direction toward the opposite side to the casing 10. The first pivot shaft portion 63 has a first curved surface 631. The first curved surface 631 is a cylindrical outer peripheral surface centered on an axis extending in the second direction.

Further, the housing of the developing cartridge 1 has a second rotation shaft 17 at the other end in the second direction. In detail, the casing 10 has a second rotation shaft 17 at the other end in the second direction. The second pivot shaft portion 17 is located at one end of the second outer surface 12 of the casing 10 in the first direction. Further, the second rotation shaft portion 17 is positioned farther from the agitator shaft 21 than the developing roller 30 in the first direction. The second pivot shaft portion 17 protrudes from the second outer surface 12 in the second direction. The second pivot shaft portion 17 has a second curved surface 171. The second curved surface 171 is a cylindrical outer peripheral surface centered on an axis extending in the second direction.

The first pivoting shaft 63 and the second pivoting shaft 17 are spaced apart in the second direction. However, at least a portion of the first pivoting shaft portion 63 and at least a portion of the second pivoting shaft portion 17 are in an overlapping position when viewed in the second direction. Further, the first pivoting shaft portion 63 and the second pivoting shaft portion 17 are both cylindrical and have the same diameter. The diameters of the first rotation shaft 63 and the second rotation shaft 17 are smaller than the diameter of the outer peripheral surface of the developing roller 30. Further, the distance between the developing roller 30 and the first rotation shaft portion 63 in the first direction is a fixed distance. Further, the distance between the developing roller 30 and the second rotation shaft portion 17 in the first direction is also a constant distance.

When mounting the developing cartridge 1 in the cartridge holding portion 91 of the drum unit 9, the frame 90 of the drum unit 9 includes the first curved surface 631 of the first pivoting shaft 63 and the second curved surface of the second pivoting shaft 17. 171 contacts. Then, the casing 10, the agitator 20, the developing roller 30, the gear portion 40, the gear cover 50, and the bearing plate 60 perform the first rotation in response to the external force received from the first pressing portion 97 and the second pressing portion 98 described later. The drum unit 9 is rotated with respect to the drum unit 9 around the shaft portion 63 and the second rotation shaft portion 17.

<1-2. Mounting operation of developing cartridge to drum unit>
Subsequently, an operation when the developing cartridge 1 is attached to the cartridge holding portion 91 of the drum unit 9 will be described.

As shown in FIG. 1, the frame 90 of the drum unit 9 has a first guide surface 93, a first contact receiving surface 94, a second guide surface 95, and a second contact receiving surface 96 for each cartridge holding portion 91. The first guide surface 93, the first contact receiving surface 94, the second guide surface 95, and the second contact receiving surface 96 are in a third direction intersecting (preferably orthogonal) to the first direction and the second direction, It faces the photosensitive drum 92.

The first guide surface 93 and the first contact receiving surface 94 are located at one end of the cartridge holding portion 91 in the second direction. The first guide surface 93 and the first contact receiving surface 94 extend in the second direction. Also, the first guide surface 93 and the first contact receiving surface 94 project toward the photosensitive drum 92. Specifically, as the first guide surface 93 approaches the first contact receiving surface 94, the first guide surface 93 inclines so as to approach the photosensitive drum 92. The first contact receiving surface 94 inclines toward the photosensitive drum 92 as it approaches the first guide surface 93.

The second guide surface 95 and the second contact receiving surface 96 are located at the other end of the cartridge holding portion 91 in the second direction. The second guide surface 95 and the second contact receiving surface 96 extend in the second direction. The second guide surface 95 and the second contact receiving surface 96 project toward the photosensitive drum 92. Specifically, the second guide surface 95 is inclined so as to approach the photosensitive drum 92 as it approaches the second contact receiving surface 96. The second contact receiving surface 96 inclines to approach the photosensitive drum 92 as it approaches the second guide surface 95.

Further, as shown in FIG. 1, the frame 90 of the drum unit 9 has a first pressing portion 97 and a second pressing portion 98 for each cartridge holding portion 91. The first pressing portion 97 is located at one end of the cartridge holding portion 91 in the second direction. Further, the first pressing portion 97 is located farther from the first contact receiving surface 94 than the first guide surface 93. The second pressing portion 98 is located at the other end of the cartridge holding portion 91 in the second direction. Further, the second pressing portion 98 is positioned farther from the second contact receiving surface 96 than the second guide surface 95.

FIGS. 3 to 5 show how the developing cartridge 1 is attached to the cartridge holding portion 91. FIG. As shown in FIGS. 3 to 5, the first pressing portion 97 has a coil spring 971 and a pressing member 972. The coil spring 971 is an elastic member that can expand and contract in the third direction. One end of the coil spring 971 in the third direction is connected to the frame 90 of the drum unit 9. The other end of the coil spring 971 in the third direction is connected to the pressing member 972. The coil spring 971 is compressed in the third direction than the natural length.

In addition, the coil spring 971 expands and contracts in the third direction between the first length and the second length shorter than the first length. When the coil spring 971 is in the first length, the pressing member 972 is in the first position. When the coil spring 971 has a second length, the pressing member 972 is located at a second position closer to one end of the coil spring 971 than at the first position. The pressing member 972 has a pressing surface 973 projecting in a direction away from the coil spring 971 in the third direction.

Similarly to the first pressing portion 97, the second pressing portion 98 also has a coil spring and a pressing member having a pressing surface.

When the developing cartridge 1 is inserted into the cartridge holding portion 91, as shown in FIG. 3, first, the first pivot shaft portion 63 contacts the first guide surface 93 of the frame 90. Similarly, the second pivot shaft 17 contacts the second guide surface 95 of the frame 90. Subsequently, when the developing cartridge 1 is further inserted, as shown in FIG. 4, the first pivot shaft portion 63 moves along the first guide surface 93. Then, as shown in FIG. 5, the first curved surface 631 of the first rotation shaft 63 contacts the first contact receiving surface 94. Similarly, the second pivot shaft portion 17 moves along the second guide surface 95. Then, the second curved surface 171 of the second rotation shaft portion 17 contacts the second contact receiving surface 96.

Subsequently, among the outer surfaces of the extending portion 51 of the gear cover 50, one surface in the third direction (hereinafter, referred to as “first pressing receiving surface”) 54 contacts the first pressing portion 97. Specifically, the first pressing receiving surface 54 contacts the pressing surface 973. Thereby, the length of the coil spring 971 contracts from the first length to the second length. The first pressure receiving surface 54 receives a pressing force in the third direction from the first pressing portion 97. Further, also at the other end of the casing 10 in the second direction, one surface in the third direction (hereinafter referred to as “second pressure receiving surface”) 19 contacts the second pressing portion 98. Thereby, the second pressure receiving surface 19 receives the pressing force in the third direction from the second pressing portion 98.

The first pressing receiving surface 54 is located closer to the other end 16 than the first pivot shaft 63 in the first direction. Further, the first pressing receiving surface 54 is located closer to the other end 16 than the developing roller 30 in the first direction. The second pressure receiving surface 19 is located closer to the other end 16 than the second rotation shaft 17 in the first direction. Further, the second pressure receiving surface 19 is located closer to the other end 16 than the developing roller 30 in the first direction.

The pressing force received by the first pressing receiving surface 54 and the second pressing receiving surface 19 has a component of force along the rotation direction about the first rotation shaft 63 and the second rotation shaft 17. . Therefore, the developing cartridge 1 receives the pressing force received by the first pressing receiving surface 54 and the second pressing receiving surface 19 around the first rotation shaft 63 and the second rotation shaft 17 in FIG. Rotate in the direction of the dashed arrow. That is, the casing 10, the agitator 20, the developing roller 30, the gear portion 40, the gear cover 50, and the bearing plate 60 rotate around the first rotation shaft portion 63 and the second rotation shaft portion 17. As a result, the developing roller 30 approaches the photosensitive drum 92. Then, as shown in FIG. 5, the outer peripheral surface of the developing roller 30 contacts the outer peripheral surface of the photosensitive drum 92. As a result, the position and attitude of the developing cartridge 1 with respect to the photosensitive drum 92 are fixed. Then, the outer peripheral surface of the photosensitive drum 92 and the outer peripheral surface of the developing roller 30 are maintained in contact with each other.

As described above, the developing cartridge 1 according to the present embodiment is not positioned on the frame 90 of the drum unit 9 using the developing roller shaft 32, but the first rotation shaft 63 and the first rotating shaft 63 different from the developing roller shaft 32. The developing roller 30 is positioned using the rotation shaft 17. The developing roller shaft 32 and the frame 90 of the drum unit 9 are not in contact with each other. That is, the developing roller shaft 32 and the frame 90 of the drum unit 9 are not in direct contact with each other nor in indirect contact with other members. Therefore, the developing roller 30 can be positioned independently of the dimensional accuracy of the developing roller shaft 32.

Conventionally, positioning of the developing roller with respect to the photosensitive drum involved many parts. Specifically, the outer peripheral surface of the photosensitive drum, the bearing of the photosensitive drum provided on the frame of the drum unit, and the guide groove for the developing roller shaft provided on the frame concerned with the positioning of the developing roller with respect to the photosensitive drum . Further, the developing roller shaft, and in some cases, a collar attached to the developing roller shaft, a bearing of the developing roller, and an outer peripheral surface of the developing roller are also involved in the positioning of the developing roller with respect to the photosensitive drum. On the other hand, in the structure of the present embodiment, the photosensitive drum 92 has the photosensitive drum 92, the first pivot shaft 63 and the second pivot shaft 17 of the bearing plate 60, and the outer peripheral surface of the developing roller 30. Positioning of the developing roller 30 with respect to 92 can be performed. This reduces the number of parts involved in positioning. As a result, it is possible to suppress the positioning error caused by the tolerance of each part.

Also, conventionally, the guide grooves of the frame are provided along the direction in which the photosensitive drums are arranged. Therefore, in the conventional structure, it is necessary to widen the interval between the adjacent photosensitive drums. On the other hand, in the structure of the present embodiment, it is not necessary to provide the frame 90 with the guide groove. Therefore, the distance between the adjacent photosensitive drums 92 can be made narrower than in the prior art.

Here, as shown in FIG. 5, the distance in the first direction from the first rotation shaft 63 to the developing roller 30 is taken as a first distance d1. Further, the distance in the first direction from the first rotation shaft 63 to the first pressing receiving surface 54 is taken as a first specific distance ds1. Similarly, the distance in the first direction from the second rotation shaft portion 17 to the developing roller 30 is taken as a second distance d2. Further, the distance from the second rotation shaft portion 17 to the second pressing receiving surface 19 is taken as a second specific distance ds2.

As shown in FIG. 5, the first specific distance ds1 is larger than the first distance d1. Similarly, the second specific distance ds2 is larger than the second distance d2. For this reason, the pressing force received by the first pressing receiving surface 54 and the second pressing receiving surface 19 is amplified by the lever principle and transmitted to the developing roller 30. Therefore, the outer peripheral surface of the developing roller 30 can be more strongly in contact with the outer peripheral surface of the photosensitive drum 92.

As described above, in this embodiment, the first pivot shaft portion 63 contacts the first contact receiving surface 94 after contacting the first guide surface 93. In addition, after the second pivot shaft portion 17 contacts the second guide surface 95, the second pivot shaft portion 17 contacts the second contact receiving surface 96. However, the first rotation shaft portion 63 may contact the first contact receiving surface 94 after contacting the outer peripheral surface of the photosensitive drum 92 without contacting the first guide surface 93. In addition, the second pivot shaft portion 17 may contact the second contact receiving surface 96 after contacting the outer peripheral surface of the photosensitive drum 92 without contacting the second guide surface 95.

In the present embodiment, the first rotation shaft 63 is included in the bearing plate 60 that constitutes a part of the housing of the developing cartridge 1. For this reason, it is not necessary to provide a member having the first rotation shaft 63 separately from the bearing plate 60. Thereby, the number of parts of the developing cartridge 1 can be suppressed. Further, in the present embodiment, the casing 10 that constitutes a part of the housing of the developing cartridge 1 includes the second rotation shaft portion 17. For this reason, it is not necessary to provide a member having the second rotation shaft portion 17 separately from the casing 10. Thereby, the number of parts of the developing cartridge 1 can be suppressed. However, the first rotation shaft 63 and the second rotation shaft 17 may be provided on a member different from the housing of the developing cartridge 1.

<1-3. Separation operation of developing cartridge>
After mounting the developing cartridge 1 on the drum unit 9, the image forming apparatus can perform a so-called "separation operation" in which the developing roller 30 is temporarily pulled away from the photosensitive drum 92. Hereinafter, this separation operation will be described. FIG. 6 is a view showing a state when the separation operation is performed.

As shown in FIG. 6, the gear cover 50 has a separation boss 55. The separation boss 55 protrudes in the third direction from a surface of the outer surface of the extension portion 51 opposite to the first pressing receiving surface 54 in the third direction. The separation boss 55 is located closer to the other end 16 than the first rotation shaft 63 in the first direction. Further, the separation boss 55 is located closer to the other end 16 than the developing roller 30 in the first direction.

On the other hand, the drum unit 9 has a separation lever 99. The separation lever 99 is rotatable about a rotation axis extending in the second direction. At the time of the separation operation, the separation lever 99 is rotated by the driving force from the image forming apparatus. Then, as shown in FIG. 6, the tip of the separation lever 99 contacts the end surface (receiving surface) of the separation boss 55. Then, the tip of the separation lever 99 presses the end surface of the separation boss 55 in the third direction.

The pressing force (separation force) received by the end surface of the separation boss 55 has a component of a force along the rotation direction about the first rotation shaft portion 63 and the second rotation shaft portion 17. For this reason, the developing cartridge 1 is pivoted about the first pivot shaft portion 63 and the second pivot shaft portion 17 in the direction of the dashed arrow in FIG. 6 by the pressing force received by the separation boss 55. That is, the casing 10, the agitator 20, the developing roller 30, the gear portion 40, the gear cover 50, and the bearing plate 60 rotate around the first rotation shaft portion 63 and the second rotation shaft portion 17. As a result, the outer peripheral surface of the developing roller 30 is separated from the outer peripheral surface of the photosensitive drum 92 in the third direction.

<2. Second embodiment>
Subsequently, the developing cartridge 1 of the second embodiment will be described.

The developing cartridge 1 according to the second embodiment is different from the first embodiment in that the first roller 71 and the second roller are included. In the following, differences from the first embodiment will be mainly described, and parts equivalent to the first embodiment will be assigned the same reference numerals as in the first embodiment and redundant description will be omitted.

FIG. 7 is a partial perspective view of the developing cartridge 1 of the second embodiment. As shown in FIG. 7, in the second embodiment, the bearing plate 60 has a first roller shaft 64. The first roller shaft 64 is located at one end of the bearing plate 60 in the first direction. That is, the first roller shaft 64 is positioned farther from the agitator shaft 21 than the developing roller 30 in the first direction. Further, the first roller shaft 64 protrudes from the flat plate portion 61 in the second direction toward the opposite side to the casing 10.

Similarly, the casing 10 has a second roller shaft (not shown). The second roller shaft is located at one end of the second outer surface 12 of the casing 10 in the first direction. That is, the second roller shaft is located farther from the agitator shaft 21 than the developing roller 30 in the first direction. Further, the second roller shaft protrudes from the second outer surface 12 of the casing 10 in the second direction.

The first roller 71 is a roller having a cylindrical outer peripheral surface (first curved surface). The second roller (not shown) is a roller having a cylindrical outer peripheral surface (second curved surface). The diameters of the outer peripheral surfaces of the first roller 71 and the second roller are smaller than the diameter of the outer peripheral surface of the developing roller 30. The first roller 71 is supported by the first roller shaft 64 and is rotatable about a rotational axis extending in the second direction. The second roller is rotatable about a rotational axis extending in the second direction while being supported by the second roller shaft. The first roller 71 and the second roller are positioned farther from the agitator shaft 21 than the developing roller 30 in the first direction.

The first roller 71 and the second roller are separated in the second direction. However, at least a portion of the first roller 71 and at least a portion of the second roller 71 are in an overlapping position when viewed in the second direction. Further, the outer peripheral surface of the first roller 71 and the outer peripheral surface of the second roller have the same diameter. Further, the distance between the developing roller 30 and the first roller 71 in the first direction is a fixed distance. Further, the distance between the developing roller 30 and the second roller in the first direction is also a fixed distance.

In the present embodiment, the first roller 71 and the second roller serve as a rotating shaft. That is, when the developing cartridge 1 is mounted to the cartridge holding portion 91 of the drum unit 9, the outer peripheral surface of the first roller 71 and the outer peripheral surface of the second roller contact the frame 90 of the drum unit 9. The casing 10, the agitator 20, the developing roller 30, the gear portion 40, the gear cover 50, and the bearing plate 60 correspond to the first roller 71 and the bearing plate 60 according to the external force received from the first pressing portion 97 and the second pressing portion 98. (2) It rotates with respect to the drum unit 9 centering on the roller. As a result, the outer peripheral surface of the developing roller 30 contacts the outer peripheral surface of the photosensitive drum 92.

As described above, also in the second embodiment, the developing roller shaft 32 is not positioned on the frame 90 of the drum unit 9 but the first roller 71 and the second roller different from the developing roller shaft 32 are used. , Position the developing roller 30. The developing roller shaft 32 and the frame 90 of the drum unit 9 are not in contact with each other. That is, the developing roller shaft 32 and the frame 90 of the drum unit 9 do not make direct contact, nor do they make indirect contact via other members. Therefore, the developing roller 30 can be positioned independently of the dimensional accuracy of the developing roller shaft 32.

Also in the second embodiment, the positioning of the developing roller 30 with respect to the photosensitive drum 92 can be performed with a smaller number of parts than in the prior art. For this reason, the positioning error resulting from the tolerance of each part can be suppressed.

In particular, in the present embodiment, the outer peripheral surface of the first roller 71 which is the first curved surface is rotatable around the first roller shaft 64. Further, the outer peripheral surface of the second roller, which is the second curved surface, can rotate around the second roller shaft. Therefore, when the first roller 71 and the second roller contact the frame 90 of the drum unit 9, rubbing occurs between the outer peripheral surface of the first roller 71 or the outer peripheral surface of the second roller and the frame 90. Hateful.

Further, in the present embodiment, the first roller shaft 64 is included in the bearing plate 60 which constitutes a part of the housing of the developing cartridge 1. Therefore, there is no need to provide a member having the first roller shaft 64 separately from the bearing plate 60. Thereby, the number of parts of the developing cartridge 1 can be suppressed. Further, in the present embodiment, the second roller shaft is included in the casing 10 that constitutes a part of the housing of the developing cartridge 1. For this reason, there is no need to provide a member having the second roller shaft separately from the casing 10. Thereby, the number of parts of the developing cartridge 1 can be suppressed. However, the first roller shaft 64 and the second roller shaft may be provided on a member different from the housing of the developing cartridge 1.

In the present embodiment, the diameters of the outer peripheral surfaces of the first roller 71 and the second roller are smaller than the diameter of the outer peripheral surface of the developing roller 30. Thereby, the mounting of the developing cartridge 1 to the cartridge holding portion 91 is facilitated. In particular, the downsizing of the drum unit 9 and the mounting ease of the developing cartridge 1 to the cartridge holding portion 91 can be easily achieved at the same time.

Instead of the bearing plate 60 having the first roller shaft 64, the first roller 71 may have the first roller shaft. In this case, the bearing plate 60 may have an opening into which the first roller shaft can be inserted. Also, instead of the casing 10 having the second roller shaft, the second roller may have the second roller shaft. In this case, the casing 10 may have an opening through which the second roller shaft can be inserted.

<3. Modified example>
As mentioned above, although 1st Embodiment and 2nd Embodiment were described, this invention is not limited to said embodiment.

In the above embodiment, the developing cartridge has the first rotation shaft 63 and the second rotation shaft 17. However, the number of rotation shaft portions of the developing cartridge may be one, or three or more. For example, the developing cartridge may have one rotation shaft extending from one end to the other end in the second direction.

In the above embodiment, the frame 90 of the drum unit 9 has the first pressing portion 95 and the second pressing portion 96 for each cartridge holding portion 91. However, instead of the frame 90, the developing cartridge 1 may have a first pressing portion and a second pressing portion. In this case, the first pressing portion and the second pressing portion of the developing cartridge 1 contact the frame 90, and the developing cartridge 1 rotates with respect to the frame 90 according to the pressing force.

Further, in the above-described embodiment, the developing cartridge 1 has the first rotation shaft portion having the first curved surface. However, as long as the first pivoting shaft portion has the first curved surface, the shape of the first pivoting shaft portion may be different from the above embodiment. For example, the first curved surface may be an arc-shaped surface as viewed in the second direction. In this case, the developing cartridge 1 may rotate with respect to the drum unit 9 about the first curved surface. More specifically, the casing 10, the agitator 20, the developing roller 30, the gear portion 40, the gear cover 50, and the bearing plate 60 may rotate with respect to the drum unit 9 around the first curved surface. Moreover, like the said embodiment, the 1st curved surface of a 1st rotation axial part may be annular | circular shape.

Further, in a state where the first curved surface is in contact with a part of the drum unit 9, the developing cartridge 1 may rotate with respect to the drum unit 9 about the first rotation shaft portion. More specifically, with the first curved surface in contact with a part of the drum unit 9, the casing 10, the agitator 20, the developing roller 30, the gear portion 40, the gear cover 50, and the bearing plate 60 perform the first rotation. You may rotate with respect to the drum unit 9 centering on an axial part.

Further, in the above-described embodiment, the developing cartridge 1 includes the second rotation shaft portion having the second curved surface. However, as long as the second pivoting shaft portion has the second curved surface, the shape of the second pivoting shaft portion may be different from that of the above embodiment. For example, the second curved surface may be an arc-shaped surface as viewed in the second direction. In this case, the developing cartridge 1 may rotate with respect to the drum unit 9 about the second curved surface. More specifically, the casing 10, the agitator 20, the developing roller 30, the gear portion 40, the gear cover 50, and the bearing plate 60 may rotate with respect to the drum unit 9 around the second curved surface. Moreover, like the said embodiment, the 2nd curved surface of a 2nd rotation axial part may be annular ring shape.

Further, in a state where the second curved surface is in contact with a part of the drum unit 9, the developing cartridge 1 may rotate with respect to the drum unit 9 about the second rotation shaft portion. More specifically, with the second curved surface in contact with a part of the drum unit 9, the casing 10, the agitator 20, the developing roller 30, the gear portion 40, the gear cover 50, and the bearing plate 60 perform the second rotation. You may rotate with respect to the drum unit 9 centering on an axial part.

Further, the shape of each part of the developing cartridge may be different from the shape shown in each drawing of the present application. In addition, the elements appearing in the first embodiment, the second embodiment, and the modification may be combined appropriately as long as no contradiction occurs.

DESCRIPTION OF SYMBOLS 1 developing cartridge 9 drum unit 10 casing 11 1st outer surface 12 2nd outer surface 13 accommodation chamber 14 opening part 15 one end part 16 other end part 17 2nd rotation axial part 19 2nd press receiving surface 20 agitator 21 agitator shaft 22 agitation Blade 30 Developing roller 31 Developing roller main body 32 Developing roller shaft 40 Gear portion 41 Coupling 42 Agitator gear 43 Developing roller gear 50 Gear cover 51 Extension portion 52 Circular hole 54 First pressure receiving surface 55 Separation boss 60 Bearing plate 61 Flat portion 62 Bearing projection 63 first rotation shaft 64 first roller shaft 71 first roller 90 frame 91 cartridge holder 92 photosensitive drum 93 first guide surface 94 first contact bearing surface 95 second guide surface 96 second contact bearing surface 97 First pressing part 98 Second pressing part 9 9 separation lever 171 second curved surface 411 fastening hole 631 first curved surface 971 coil spring 972 pressing member 973 pressing surface

Claims

A housing capable of containing a developer, the housing having one end and the other end in the first direction;
An agitator capable of agitating the developer, the agitator having an agitator shaft extending in a second direction;
A developing roller positioned closer to the one end than the agitator shaft in the first direction, the developing roller being rotatable about a rotation axis extending in the second direction;
A first pivoting shaft portion which is located farther from the agitator shaft than the developing roller in the first direction and extends in the second direction;
A developer cartridge comprising
The developing cartridge according to claim 1, wherein the developing roller, the agitator, and the casing are rotatable about the first rotation shaft.
The developing cartridge according to claim 1, wherein
A developing cartridge according to claim 1, wherein a distance between the developing roller and the first rotation shaft portion in the first direction is a fixed distance.
The developing cartridge according to claim 1 or 2, wherein
The diameter of the first rotation shaft portion is smaller than the diameter of the outer peripheral surface of the developing roller.
The developing cartridge according to any one of claims 1 to 3, wherein
The first rotation shaft portion is separated from the developing roller by a first distance in the first direction,
The developer cartridge is further
It has a pressure receiving surface separated by a specific distance larger than the first distance from the first rotation shaft in the first direction,
The developing cartridge, wherein the developing roller, the agitator, and the housing rotate around the first rotation shaft when the pressing receiving surface receives a pressing force.
The developing cartridge according to claim 4,
The developing cartridge according to claim 1, wherein the pressure receiving surface is positioned closer to the other end than the developing roller in the first direction.
The developing cartridge according to any one of claims 1 to 5, wherein
The first rotation shaft portion is a first roller,
The developer cartridge according to claim 1, wherein the first roller is rotatable about an axis of rotation extending in the second direction.
The developing cartridge according to any one of claims 1 to 6, wherein
The developing cartridge can be mounted on a drum unit having a photosensitive drum rotatable about a rotating shaft extending in the second direction,
The developing cartridge according to claim 1, wherein the developing roller, the agitator, and the housing are rotatable relative to the drum unit about the first rotation shaft.
The developing cartridge according to claim 7, wherein
The first rotation shaft portion has a first curved surface,
When the developing cartridge is mounted on the drum unit, the developing roller, the agitator, and the housing, with the first curved surface being in contact with the frame of the drum unit, the first pivot shaft portion A developer cartridge rotating about the drum unit with respect to the drum unit;
A developing cartridge according to claim 7 or 8, wherein
When the developing roller, the agitator, and the housing rotate with respect to the drum unit around the first rotation shaft when the developing cartridge is mounted on the drum unit, the outer periphery of the developing roller A developing cartridge, the surface of which contacts the outer peripheral surface of the photosensitive drum.
The developing cartridge according to any one of claims 1 to 6, wherein
The developing cartridge can be mounted on a drum unit having a photosensitive drum rotatable about a rotating shaft extending in the second direction,
When the developing cartridge is mounted on the drum unit, the developing roller, the agitator, and the housing center on the first rotation shaft after the pressing receiving surface receives the pressing force. A developing cartridge, wherein the outer peripheral surface of the developing roller comes in contact with the outer peripheral surface of the photosensitive drum when it is rotated with respect to the drum unit.
11. The developing cartridge according to claim 10, wherein
When the developing roller, the agitator, and the housing rotate with respect to the drum unit around the first rotating shaft after the first rotating shaft contacts the frame of the drum unit. A developing cartridge, wherein an outer peripheral surface of the developing roller contacts an outer peripheral surface of the photosensitive drum.
12. The developing cartridge according to claim 11, wherein
The first rotation shaft portion has a first curved surface,
When the developing roller, the agitator, and the housing rotate with respect to the drum unit around the first rotation shaft after the first curved surface contacts the frame of the drum unit, the developing roller An outer circumferential surface of the developing cartridge contacts an outer circumferential surface of the photosensitive drum.
The developing cartridge according to any one of claims 10 to 12, wherein
A developing cartridge according to claim 1, further comprising a receiving surface for receiving a separation force in a direction to separate the developing roller from the photosensitive drum.
The developing cartridge according to any one of claims 1 to 13, wherein
A developer cartridge including the first rotation shaft portion;
The developing cartridge according to claim 1, wherein
The first pivot shaft is located at one end of the housing in the second direction,
The developer cartridge is
A second pivoting shaft portion, which is located farther from the agitator shaft than the developing roller in the first direction and extends in the second direction, and is spaced from the first pivoting shaft portion in the second direction. Further comprising a second pivoting shaft located,
A developing cartridge characterized in that the developing roller, the agitator, and the casing rotate around the first and second rotating shaft portions.
The developing cartridge according to claim 15, wherein
The distance between the developing roller and the first rotation shaft in the first direction is a constant distance,
The developing cartridge according to claim 1, wherein a distance between the developing roller and the second rotation shaft in the first direction is a fixed distance.
17. The developing cartridge according to claim 15, wherein
The diameter of the first rotation shaft portion is smaller than the diameter of the outer peripheral surface of the developing roller,
The diameter of the second rotation shaft portion is smaller than the diameter of the outer peripheral surface of the developing roller.
The developing cartridge according to any one of claims 15 to 17, wherein
The first rotation shaft portion is separated from the developing roller by a first distance in the first direction,
The second pivot shaft portion is separated from the developing roller by a second distance in the first direction.
The developer cartridge is further
In the first direction, a pressing receiving surface separated from the first and second rotating shafts by a specific distance larger than the first and second distances is provided.
When the pressing receiving surface receives a pressing force, the developing roller, the agitator, and the housing rotate around the first and second rotating shaft portions. Developer cartridge.
The developing cartridge according to claim 18, wherein
The developing cartridge according to claim 1, wherein the pressure receiving surface is positioned closer to the other end than the developing roller in the first direction.
The developer cartridge according to any one of claims 15 to 19, wherein
The first rotation shaft portion is a first roller,
The second rotation shaft portion is a second roller,
The first roller is rotatable about an axis of rotation extending in the second direction;
The developer cartridge according to claim 1, wherein the second roller is rotatable about an axis of rotation extending in the second direction.
The developing cartridge according to any one of claims 15 to 20, wherein
The developing cartridge can be mounted on a drum unit having a photosensitive drum rotatable about a rotating shaft extending in the second direction,
3. A developing cartridge according to claim 1, wherein said developing roller, said agitator and said casing are rotatable relative to said drum unit about said first and second rotating shaft portions.
22. The developing cartridge according to claim 21, wherein
The first rotation shaft portion has a first curved surface,
The second pivot shaft portion has a second curved surface,
When the developing cartridge is mounted on the drum unit, the developing roller, the agitator, and the housing are in a state where the first curved surface and the second curved surface are in contact with the frame of the drum unit. A developing cartridge, which is pivoted relative to the drum unit about a first pivoting shaft portion and the second pivoting shaft portion.
A developing cartridge according to claim 21 or 22, wherein
When the developing cartridge is mounted on the drum unit, the developing roller, the agitator, and the housing rotate around the first rotating shaft and the second rotating shaft with respect to the drum unit. When moved, the outer peripheral surface of the developing roller contacts the outer peripheral surface of the photosensitive drum.
The developer cartridge according to any one of claims 15 to 19, wherein
The developing cartridge can be mounted on a drum unit having a photosensitive drum rotatable about a rotating shaft extending in the second direction,
When the developing cartridge is mounted on the drum unit, the developing roller, the agitator, and the housing are the first rotating shaft and the second after the pressing receiving surface receives the pressing force. A developing cartridge characterized in that an outer peripheral surface of the developing roller comes in contact with an outer peripheral surface of the photosensitive drum when rotating relative to the drum unit around a rotating shaft portion.
25. The developing cartridge according to claim 24, wherein
After the first and second pivot shafts come into contact with the frame of the drum unit, the developing roller, the agitator, and the housing move together with the first and second pivot shafts. A developing cartridge characterized in that an outer peripheral surface of the developing roller comes in contact with an outer peripheral surface of the photosensitive drum when it is rotated with respect to the drum unit about a moving shaft.
26. The developing cartridge according to claim 25, wherein
The first rotation shaft portion has a first curved surface,
The second pivot shaft portion has a second curved surface,
After the first curved surface and the second curved surface make contact with the frame of the drum unit, the developing roller, the agitator, and the housing are the first pivot shaft portion and the second pivot shaft portion. A developing cartridge characterized in that the outer peripheral surface of the developing roller comes in contact with the outer peripheral surface of the photosensitive drum when it is rotated with respect to the drum unit as a center.
The developing cartridge according to any one of claims 24 to 26, wherein
A developing cartridge according to claim 1, further comprising a receiving surface for receiving a separation force in a direction to separate the developing roller from the photosensitive drum.
The developing cartridge according to any one of claims 15 to 27, wherein
A developer cartridge including the first rotation shaft and the second rotation shaft;
28. A developing cartridge according to any one of claims 7 to 13 or 21 to 27.
The developing roller is
A developing roller shaft extending in a second direction along the rotation axis;
A developing cartridge characterized in that the developing roller shaft and the drum unit are not in contact with each other.