JP2022015623A - Developing cartridge - Google Patents

Abstract

To prevent displacement of the position of a developing cartridge.SOLUTION: A developing cartridge 10 comprises: a developing roller 12; a coupling 22 that is rotatable in both a first rotation direction D1 and a second rotation direction D2; and a magnetic member 70. In a state in which the developing cartridge 10 is attached to the drum cartridge 5, when the coupling 22 rotates in the first rotation direction D1, it generates first moment M1 in a direction in which the developing cartridge 10 approaches the drum cartridge 5, and when the coupling rotates in the second rotation direction D2, it generates second moment M2 in a direction in which the developing cartridge 10 moves away from the drum cartridge 5. The magnetic member 70 causes the developing cartridge 10 to generate a magnetic force in a direction to approach the drum cartridge 5. When the coupling 22 rotates in the second rotation direction D2, the developing cartridge 10 resists the second moment M2 and is urged by the magnetic force in the direction to approach the drum cartridge 5.SELECTED DRAWING: Figure 13

Description

The present disclosure relates to a developing cartridge comprising a coupling into which a driving force is input.

The developing cartridge has a coupling that receives a driving force from the image forming apparatus main body. Then, there is known an image forming apparatus that appropriately supplies toner from a developer cartridge to a housing of a developing cartridge according to the remaining amount of toner in the housing of the developing cartridge (Patent Document 1). In this image forming apparatus, the solenoid of the main body of the apparatus is operated to move the lever on the main body side, and the lever on the main body side accesses the lever on the developing cartridge side to supply toner.

Japanese Unexamined Patent Publication No. 2017-181946

However, in the conventional apparatus, toner cannot be supplied to the developing chamber of the developing cartridge only by the operation of the coupling. Therefore, there is a demand for a developing cartridge that can supply toner at a required timing only by a coupling operation.

When the coupling is rotated in the first rotation direction, the developing roller is rotated without supplying toner, and when the coupling is rotated in the second rotation direction opposite to the first rotation direction, the developing roller is supplied with toner. A developing cartridge having a configuration in which the toner is rotated can be considered.

However, when the coupling drive is in the first rotation direction and the second rotation direction, the direction of the rotation moment applied to the developing cartridge changes from the coupling drive, so that the position of the developing cartridge may shift. rice field.

Therefore, it is an object of the present disclosure to prevent the position of the developing cartridge from being displaced.

The development cartridge consists of a developing roller that can rotate about the first axis that extends in the axial direction, and a cup that can rotate in both the first rotation direction and the second rotation direction opposite to the first rotation direction for the second axis that extends in the axial direction. It includes a ring and a magnetic member.
The coupling provides the first moment in the direction in which the developing cartridge approaches the image forming apparatus or the drum cartridge when the developing cartridge rotates in the first rotation direction while the developing cartridge is attached to the image forming apparatus or the drum cartridge. Generated and when the coupling rotates in the second rotation direction, the developing cartridge generates a second moment in the direction away from the image forming apparatus or the drum cartridge.
The magnetic member causes the developing cartridge to generate a magnetic force in a direction approaching the image forming apparatus or the drum cartridge.
When the coupling rotates in the second rotation direction, the developing cartridge resists the second moment and is urged by the magnetic force toward the image forming apparatus or the drum cartridge.

According to this configuration, the coupling rotates in the second rotation direction even if the direction of the moment applied to the developing cartridge changes depending on whether the coupling rotates in the first rotation direction or the second rotation direction. In this case, the developing cartridge resists the second moment and is urged by the magnetic force in a direction approaching the image forming apparatus or the drum cartridge, so that the developing cartridge can be suppressed from moving. As a result, it is possible to prevent the position of the developing cartridge from shifting.

The magnetic member can be configured to be located farther from the developing roller than the coupling.

According to this, it is possible to suppress the position of the developing cartridge from being displaced even if the magnetic force is small, as compared with the case where the magnetic member is located closer to the developing roller than the coupling.

The developing cartridge may further include a housing capable of accommodating toner, and the magnetic member may be configured to be located on one side and the other side of the housing in the axial direction.

According to this, it is possible to further suppress the position of the developing cartridge from being displaced due to the magnetic force generated by the magnetic members located on both sides in the axial direction of the housing.

The developing cartridge further comprises a first contact surface of the image forming apparatus or drum cartridge that can be contacted with the positioning surface, and the coupling is such that the developing cartridge is mounted on the image forming apparatus or the drum cartridge. When rotating in one rotation direction, a first moment is generated in the direction in which the first contact surface approaches the positioning surface, and when the coupling rotates in the second rotation direction, the direction in which the first contact surface separates from the positioning surface. When the coupling rotates in the second rotation direction, the developing cartridge is configured to resist the second moment and to be urged by the magnetic force in the direction in which the first contact surface approaches the positioning surface. can do.

The developing cartridge may further include a housing capable of accommodating toner, and the first contact surface may be configured to be located on one side and the other side of the housing in the axial direction.

This enables stable support of the developing cartridge.

The first contact surface may be configured to be located above the positioning surface when the developing cartridge is mounted on the image forming apparatus.

According to this, in addition to the magnetic force, it is possible to further suppress the position of the developing cartridge from being displaced due to the moment in the direction in which the first contact surface generated by the weight of the developing cartridge approaches the positioning surface.

When the coupling rotates in the second rotation direction, the moment in the direction in which the first contact surface generated by the magnetic force approaches the positioning surface and the moment in the direction in which the first contact surface generated by the weight of the developing cartridge approaches the positioning surface. The sum of can be configured to be larger than the second moment.

The developing cartridge can be configured to be mountable on a drum cartridge having a photoconductor drum and a positioning surface.

The developing cartridge further comprises a second contact surface that receives a pressing force for pressing the developing roller against the photoconductor drum, and the first contact surface or the positioning surface is a roller that is rotatable about a third axis extending in the axial direction. It can be configured to be the outer peripheral surface of.

According to this, it is possible to suppress the friction generated by the contact between the first contact surface and the positioning surface from affecting the pressing load due to the rotation of the roller.

The second contact surface may be configured to generate a moment in the developing cartridge in the direction in which the first contact surface approaches the positioning surface when a pressing force is applied.

According to this, it is possible to further suppress the position of the developing cartridge from being displaced due to the pressing force in addition to the magnetic force.

When the coupling rotates in the second rotation direction, the moment in the direction in which the first contact surface generated by the magnetic force approaches the positioning surface and the moment in the direction in which the first contact surface generated by the weight of the developing cartridge approaches the positioning surface. The sum of the moment in the direction in which the first contact surface approaches the positioning surface, which is generated by the pressing force received by the second contact surface, can be larger than the second moment.

The magnetic member may be a roller made of a magnetic material, the first contact surface may be an outer peripheral surface of the roller, and the positioning surface may be made of a magnet.

The positioning surface is an outer peripheral surface of a roller made of a magnetic material, and the magnetic member has a first contact surface and can be configured to be made of a magnet.

The developing cartridge is a rib having a first contact surface, further including a rib sandwiched between the positioning surface and a magnetic member, and the magnetic member is composed of a magnet, and the rib is brought into contact with the positioning surface by magnetic force. It can be configured to be urged in the direction.

The coupling has a coupling gear for rotating the developing roller, and the developing cartridge is a housing and a developing chamber located inside the housing, which can accommodate toner for supplying to the developing roller. A developing chamber, a toner accommodating chamber located inside the housing, a toner accommodating chamber capable of accommodating toner to be supplied to the developing chamber, and an auger capable of supplying the toner in the toner accommodating chamber to the developing chamber. Alternatively, the agitator is an auger that can rotate about an auger shaft that extends in the axial direction, or the agitator, a transfer gear that can rotate with the auger or the agitator, and a coupling gear that mesh with each other, and the first rotation direction and the second rotation. In a moving gear that can rotate in both directions, a moving gear that can move between the first position that meshes with the transfer gear and the second position that does not mesh with the transfer gear while meshing with the coupling gear, and is a cup. The configuration may further include a moving gear located at the first position when the ring gear rotates in the second rotation direction and located at the second position when the coupling gear rotates in the first rotation direction.

The development cartridge is a coupling in the axial direction with a first gear for rotating the development roller and a second gear that meshes with the first gear and is rotatable in the second rotation direction with respect to the second axis. A clutch that is located between and the second gear and rotates with the coupling. When the coupling rotates in the second rotation direction, it engages with a part of the second gear and is engaged with the second gear together with the coupling gear. A cup is provided with a clutch that does not engage with a part of the second gear and does not rotate the second gear together with the coupling when the coupling rotates in the first rotation direction. When the ring gear rotates in the second rotation direction, the moving gear is located in the first position and does not mesh with the first gear, and the second gear disengages the clutch in response to the coupling gear rotating in the second rotation direction. While rotating in the second rotation direction together with the coupling gear, the first gear rotates in the first rotation direction due to meshing with the second gear, and when the coupling gear rotates in the first rotation direction, the moving gear is the first. Located at two positions, the moving gear rotates in the second rotation direction due to the engagement with the coupling gear, and the first gear rotates in the first rotation direction as the coupling gear rotates in the first rotation direction. , It can be configured to rotate in the first rotation direction by meshing with the moving gear.

When the coupling gear rotates in the first rotation direction, the clutch does not engage with a part of the second gear, and the second gear meshes with the first gear so that the first gear rotates in the first rotation direction. It can be configured to rotate in the second rotation direction accordingly.

The clutch may be configured to be movable along the axial direction between an engaging position that engages with a portion of the second gear and a disengagement position that does not engage with a portion of the second gear.

According to the present disclosure, it is possible to prevent the position of the developing cartridge from being displaced.

It is sectional drawing of the image forming apparatus of 1st Embodiment. It is sectional drawing of the development cartridge. It is a perspective view of the development cartridge. It is an exploded perspective view which shows one side in the axial direction of a developing cartridge in a state where a gear cover is removed. It is a perspective view which shows one side in the axial direction of a developing cartridge in a state where a gear cover is removed. It is an exploded perspective view (a) of a coupling gear, a clutch and a 2nd gear, and the perspective view (b) of a 2nd gear. It is a perspective view (a) which looked at the clutch from one side in the axial direction, and is a perspective view (b) which looked at from the other side in the axial direction. A perspective view (a) of the coupling viewed from one side in the axial direction, a perspective view (b) and a plan view (c) of the coupling viewed from the other side in the axial direction, and a protruding piece of the coupling along the rotation direction. It is XX cross-sectional view (d) cut by the plane. It is a figure (a), (b) which shows the relationship of each part of a coupling, a clutch and a shaft when a clutch is positioned at an engaging position. It is a figure (a), (b) which shows the relationship of each part of a coupling, a clutch and a shaft when a clutch is in a disengagement position. It is a side view which shows one side in the axial direction of a developing cartridge in a state where a drum cartridge and a gear cover are removed. It is a figure which shows the cross section of a drum cartridge, and the side surface on one side in the axial direction of a developing cartridge in a state where a gear cover is removed. It is a figure which shows the cross section of a drum cartridge, and the side surface on one side in the axial direction of a developing cartridge in a state where a gear cover is removed, and is the figure explaining the moment generated when the coupling rotates clockwise (a). It is a figure (b) explaining the moment generated when the coupling rotates counterclockwise. It is a figure (a) explaining the meshing of a gear when a moving gear is located in a 2nd position, and a figure (b) which shows the meshing of a gear in the YY cross section of (a). It is a figure (a) explaining the meshing of a gear when a moving gear is in a 1st position, and a figure (b) which shows the meshing of a gear in the ZZ cross section of (a). It is a figure which shows the cross section of the drum cartridge of 2nd Embodiment, and the side surface on one side in the axial direction of a developing cartridge in a state where a gear cover is removed. In the third embodiment, the cross section of the drum cartridge, the view (a) showing one side surface of the developing cartridge in the axial direction in the state where the gear cover is removed, and the perspective view (b) of the magnetic member, the rib, and the roller. be. It is a figure which shows the cross section of the drum cartridge of 4th Embodiment, and the side surface on one side in the axial direction of a developing cartridge in a state where a gear cover is removed.

Next, the first embodiment of the present disclosure will be described in detail with reference to the drawings.

As shown in FIG. 1, the image forming apparatus 1 mainly includes a main body housing 2, a paper feeding unit 3, an image forming unit 4, and a control unit CU.

The main body housing 2 has a front cover 2A and a paper output tray 2B located on the upper part of the main body housing 2. The main body housing 2 includes a paper feeding unit 3 and an image forming unit 4 inside. By opening the front cover 2A, the developing cartridge 10 is detachably attached.

The paper feed unit 3 accommodates the paper S. Then, the paper feeding unit 3 supplies the paper S to the image forming unit 4 one by one.

The image forming unit 4 includes a drum cartridge 5, a developing cartridge 10, an exposure device (not shown), and a fixing device 4C.

The drum cartridge 5 includes a frame 5A, a photoconductor drum 5B rotatably supported by the frame 5A, and a transfer roller 5T. The transfer roller 5T faces the photoconductor drum 5B. The transfer roller 5T is conveyed while sandwiching the paper S with the photoconductor drum 5B.

The developing cartridge 10 can be attached to the drum cartridge 5. Specifically, the developing cartridge 10 is removable from the drum cartridge 5. The developing cartridge 10 is attached to and detached from the image forming apparatus 1 in a state of being attached to the drum cartridge 5.

As shown in FIG. 2, the developing cartridge 10 includes a housing 11, a developing roller 12, a supply roller 13, a first agitator 14, a second agitator 15, and an auger 16.

The housing 11 has a developing chamber 11A and a toner accommodating chamber 11B. The developing chamber 11A is located inside the housing 11. The toner storage chamber 11B is located inside the housing 11. The developing chamber 11A and the toner accommodating chamber 11B are separated by a partition wall 11W, but are connected by a passage 11P at a portion where the auger 16 is arranged. The passage 11P is arranged only in a part of the housing 11 in the axial direction.
A developing roller 12 and a supply roller 13 are arranged in the developing chamber 11A. The developing chamber 11A can accommodate the toner T to be supplied to the developing roller 12.

The toner accommodating chamber 11B is a room separate from the developing chamber 11A and capable of accommodating the toner T for supplying to the developing chamber 11A. The toner storage chamber 11B is located farther from the developing roller 12 than the developing chamber 11A.

The developing roller 12 includes a developing roller shaft 12A extending in the axial direction and a roller portion 12B. The axial direction is the axial direction of the developing roller 12, and is also simply referred to as the axial direction. The roller portion 12B covers the outer peripheral surface of the developing roller shaft 12A. The roller portion 12B is made of conductive rubber or the like. The developing roller 12 is rotatable about the first axis A1 extending in the axial direction. The developing roller 12 is rotatably supported by the housing 11 around the developing roller shaft 12A.

The supply roller 13 supplies the toner T to the developing roller 12. The supply roller 13 includes a supply roller shaft 13A extending in the axial direction and a roller portion 13B. The roller portion 13B covers the outer peripheral surface of the supply roller shaft 13A. The roller portion 13B is made of a sponge or the like. The supply roller 13 is rotatable about the supply roller shaft 13X extending in the axial direction. The supply roller 13 can rotate about the supply roller shaft 13A.

The first agitator 14 is a plate-shaped member that is long in the axial direction. The first agitator 14 has a shaft 14A. The first agitator 14 is rotatable about the first agitator shaft 14X extending in the axial direction. The shaft 14A is rotatably supported by the housing 11 with respect to the first agitator shaft 14X. The first agitator 14 can agitate the toner T in the developing chamber 11A by rotating.

The second agitator 15 is a plate-shaped member that is long in the axial direction. The second agitator 15 has a shaft 15A. The second agitator 15 is rotatable about the second agitator shaft 15X extending in the axial direction. The shaft 15A is rotatably supported by the housing 11 with respect to the second agitator shaft 15X. The second agitator 15 can agitate the toner T in the toner accommodating chamber 11B by rotating.

The auger 16 has an auger shaft 16A extending in the axial direction and a spiral plate 16B. The spiral plate 16B is fixed to the auger shaft 16A. The spiral plate 16B rotates together with the auger shaft 16A. The auger 16 is rotatable about an axially extending auger shaft 16X. The auger 16 can supply the toner T in the toner accommodating chamber 11B to the developing chamber 11A by rotating.

As shown in FIG. 1, the photoconductor drum 5B is charged by a charger (not shown) and exposed to an exposure apparatus to form an electrostatic latent image. The developing cartridge 10 supplies the toner T to the electrostatic latent image to form the toner image on the photoconductor drum 5B. The toner image on the photoconductor drum 5B is transferred to the paper S supplied from the paper feed unit 3 while passing between the photoconductor drum 5B and the transfer roller 5T.

The fuser 4C heat-fixes the toner image transferred to the paper S to the paper S. The paper S on which the toner image is heat-fixed is discharged to the paper output tray 2B outside the main body housing 2.

The control unit CU is a device that controls the operation of the entire image forming apparatus 1. The control unit CU rotates and controls the joint 7 for driving the developing cartridge 10 by the motor 8. The motor 8 can rotate forward and reverse. The control unit CU can control the motor 8 to rotate the joint 7 both clockwise and counterclockwise. Specifically, the control unit CU sets the motor 8 in the first state of rotating the coupling 22 clockwise and the coupling 22 counterclockwise by a transmission step of transmitting a command for controlling the motor 8 to the motor 8. It can be driven into a second state of rotation.

Next, the detailed configuration of the developing cartridge 10 will be described.
As shown in FIG. 3, the developing cartridge 10 has a gear cover 21 and a coupling 22 on the side surface 11F on one side in the axial direction of the housing 11.

The gear cover 21 has a coupling hole 21A and a shaft support hole 21B. The coupling hole 21A is a hole that exposes the coupling 22. The shaft support hole 21B extends in an arc shape centered on the second shaft A2 extending in the axial direction. The shaft support hole 21B is a hole that supports the moving gear 33 (see FIG. 4), which will be described later. The gear cover 21 is fixed to the housing 11 by a plurality of screws 91.

The coupling 22 has a recess 22A for receiving a driving force and a coupling gear 22B (see FIG. 4) for rotating the developing roller 12. The recess 22A is recessed in the axial direction. The recess 22A is exposed from the coupling hole 21A of the gear cover 21. A joint 7 (see FIG. 1) engages with the recess 22A. The coupling 22 receives a driving force from the joint 7 and has a clockwise direction as an example of the first rotation direction and a counterclockwise direction as an example of the second rotation direction opposite to the first rotation direction for the second axis A2. It can rotate to both. That is, the coupling gear 22B can rotate both clockwise and counterclockwise. In addition, in this specification, a "gear" is not limited to a gear having gear teeth and transmitting a rotational force by the gear teeth, but also includes a gear having a gear tooth and transmitting a rotational force by friction transmission.

As shown in FIGS. 4 and 5, the developing cartridge 10 includes a developing roller gear 23, a supply roller gear 24, an agitator gear 25, a conveyor gear 26, a first gear 31, a second gear 32, and a moving gear 33. A first idle gear 34, a second idle gear 35, a third idle gear 36, and a fourth idle gear 37 are further provided. Each of these gears is covered by a gear cover 21 (see FIG. 4).

The housing 11 has a shaft S2, a shaft S4, a shaft S5, a shaft S6, a shaft S7, and a bearing 11C on the side surface 11F.
The shaft S2 rotatably supports the second gear 32.
The shaft S4 rotatably supports the first idle gear 34.
The shaft S5 rotatably supports the second idle gear 35.
The shaft S6 rotatably supports the third idle gear 36.
The shaft S7 rotatably supports the fourth idle gear 37.
The bearing 11C has a shaft support hole 11D extending along an arc centered on the second shaft A2 extending in the axial direction. The bearing 11C movably and rotatably supports the moving gear 33.

The developing roller gear 23 is located at the end of the developing roller 12. More specifically, it is attached to the end of the developing roller shaft 12A. The developing roller gear 23 can rotate together with the developing roller shaft 12A.

The supply roller gear 24 is located at the end of the supply roller 13. More specifically, the supply roller gear 24 is mounted on the end of the supply roller shaft 13A. The supply roller gear 24 can rotate together with the supply roller shaft 13A.

The agitator gear 25 is attached to the end of the shaft 15A of the second agitator 15. The agitator gear 25 can rotate together with the second agitator 15.

The conveyor gear 26 is mounted on the end of the auger shaft 16A. The conveyor gear 26 can rotate together with the auger 16.

The first gear 31 is a gear for rotating the developing roller 12. The first gear 31 can rotate clockwise with respect to the first agitator shaft 14X. The first gear 31 has a large diameter gear 31A and a small diameter gear 31B having a smaller diameter than the large diameter gear 31A. The large diameter gear 31A rotates together with the small diameter gear 31B.

The second gear 32 can rotate counterclockwise with respect to the second axis A2 extending in the axial direction. The second gear 32 meshes with the first gear 31. More specifically, the second gear 32 meshes with the small diameter gear 31B of the first gear 31.

The first idle gear 34 is rotatable about the fourth axis A4 extending in the axial direction. The first idle gear 34 is rotatably supported by the shaft S4.
The first idle gear 34 has a small diameter gear 34A and a large diameter gear 34B having a larger diameter than the small diameter gear 34A. The small diameter gear 34A rotates together with the large diameter gear 34B. The first idle gear 34 meshes with the first gear 31. More specifically, the small diameter gear 34A of the first idle gear 34 meshes with the large diameter gear 31A of the first gear 31.

The second idle gear 35 is rotatable about the fifth axis A5 extending in the axial direction. The second idle gear 35 is rotatably supported by the shaft S5.
The second idle gear 35 meshes with the first idle gear 34. More specifically, the second idle gear 35 meshes with the large diameter gear 34B of the first idle gear 34.

Further, the second idle gear 35 meshes with the developing roller gear 23. Further, the second idle gear 35 meshes with the supply roller gear 24.

Therefore, when the first gear 31 rotates clockwise, the developing roller gear 23 and the developing roller 12 rotate counterclockwise via the first idle gear 34 and the second idle gear 35. Further, when the first gear 31 rotates clockwise, the supply roller gear 24 and the supply roller 13 rotate counterclockwise via the first idle gear 34 and the second idle gear 35.

The moving gear 33 has a small diameter gear 33A, a large diameter gear 33B having a larger diameter than the small diameter gear 33A, and shafts 33R and 33S. The large diameter gear 33B rotates together with the small diameter gear 33A. The moving gear 33 is rotatable both clockwise and counterclockwise with respect to the moving gear shaft 33X extending in the axial direction.

The shaft 33R projects to the other side in the axial direction along the moving gear shaft 33X. The shaft 33R engages with the shaft support hole 11D of the bearing 11C and is rotatably supported by the bearing 11C and movably supported along an arc centered on the second shaft A2.

The shaft 33S projects to one side in the axial direction along the moving gear shaft 33X. The shaft 33S engages with the shaft support hole 21B of the gear cover 21 and is rotatably supported by the gear cover 21 and movably supported along an arc centered on the second shaft A2.
The shaft 33S passes through the coil of the spring 33P, which is a compression coil spring. Then, the spring 33P generates an urging force between the gear cover 21 and the moving gear 33. As a result, the moving gear 33 is always pressed against the bearing 11C. A frictional force is generated between the moving gear 33 and the bearing 11C, and this frictional force gives resistance to the rotation of the moving gear 33 with respect to the moving gear shaft 33X.

The moving gear 33 meshes with the coupling gear 22B. More specifically, in the moving gear 33, the small diameter gear 33A always meshes with the coupling gear 22B.

Since the moving gear 33 is provided with resistance to rotation about the moving gear shaft 33X by the spring 33P, when the coupling gear 22B rotates clockwise or counterclockwise, the moving gear 33 moves integrally with the coupling gear 22B by this resistance force. try to. Therefore, when the coupling gear 22B rotates counterclockwise, it moves counterclockwise with respect to the second axis A2 together with the coupling gear 22B and is positioned at the first position (see FIG. 15) where it does not mesh with the first gear 31. do.
On the other hand, when the coupling gear 22B rotates clockwise, it moves clockwise with respect to the second axis A2 together with the coupling gear 22B and is located at the second position (see FIG. 14) where the coupling gear 22 meshes with the first gear 31.
That is, the moving gear 33 can move between the first position and the second position in a state of being meshed with the coupling gear 22B.

As shown in FIG. 14, in the moving gear 33, the large diameter gear 33B meshes with the first gear 31 at the second position. On the other hand, in the moving gear 33, neither the small diameter gear 33A nor the large diameter gear 33B meshes with the transport gear 26 at the second position.

As shown in FIG. 15, in the moving gear 33, the small diameter gear 33A meshes with the transport gear 26 at the first position. On the other hand, in the moving gear 33, neither the small diameter gear 33A nor the large diameter gear 33B meshes with the first gear 31 at the first position.

Returning to FIGS. 4 and 5, the third idle gear 36 is rotatable about the sixth axis A6 extending in the axial direction. The third idle gear 36 is rotatably supported by the shaft S6. The third idle gear 36 meshes with the conveyor gear 26.

The fourth idle gear 37 is rotatable about the seventh axis A7 extending in the axial direction. The fourth idle gear 37 is rotatably supported by the shaft S7. The fourth idle gear 37 meshes with the third idle gear 36 and the agitator gear 25.

Therefore, when the conveyor gear 26 rotates, the auger 16 rotates, and the agitator gear 25 and the second agitator 15 rotate via the third idle gear 36 and the fourth idle gear 37. That is, the auger 16 conveys the toner T from the toner accommodating chamber 11B to the developing chamber 11A via the passage 11P while the toner T in the toner accommodating chamber 11B is agitated by the second agitator 15 and the toner T is conveyed to the auger 16. do.

As shown in FIGS. 6A and 6B, the second gear 32 has a gear portion 32A and a shaft S12. The shaft S12 is formed in a cylindrical shape and rotatably supports the coupling 22. The second gear 32 has a larger diameter than the coupling gear 22B.

A clutch 40 is located between the coupling 22 and the second gear 32 in the axial direction.

The shaft S12 rotatably supports the coupling 22 and the clutch 40. Specifically, the outer peripheral surface B11 of the shaft S12 rotatably supports the coupling 22. The inner peripheral surface B12 of the shaft S12 rotatably supports the clutch 40. Specifically, the shaft S12 has a hole B13 that is recessed or penetrates in the axial direction. The clutch 40 is located in the hole B13. As a result, the clutch 40 rotates along the inner peripheral surface B12 of the hole B13. That is, the clutch 40 can rotate with respect to the shaft S12 together with the coupling 22.

The shaft S12 includes a cylindrical wall B1, a bottom wall portion B2, and a plurality of first protrusions P1. The cylindrical wall B1 has a cylindrical shape. The cylindrical wall B1 includes an outer peripheral surface B11 and an inner peripheral surface B12. The bottom wall portion B2 is located at the other end of the cylindrical wall B1 in the axial direction. The bottom wall portion B2 has a disk shape.

The plurality of first protrusions P1 project from the bottom wall portion B2 toward one side in the axial direction. The plurality of first protrusions P1 are arranged in the rotation direction of the coupling 22. The plurality of first protrusions P1 are arranged in an annular shape. The plurality of first protrusions P1 are located inside the holes B13 of the cylindrical wall B1. The plurality of first protrusions P1 are located on one end side in the axial direction of the cylindrical wall B1. Each first projection P1 has a rotation transmission surface FS1 along the axial direction and an inclined surface FS2 inclined with respect to the rotation direction of the clutch 40.

The rotation transmission surface FS1 intersects the rotation direction of the clutch 40. More preferably, the rotation transmission surface FS1 is orthogonal to the rotation direction of the clutch 40. When the clutch 40 rotates counterclockwise D2, the rotation transmission surface FS1 faces the clutch 40 (for details, refer to the first clutch surface FC1: FIG. 7, which will be described later) in the counterclockwise direction D2.

The inclined surface FS2 is a surface for moving the clutch 40 from the engaging position to the disengaging position when the clutch 40 rotates clockwise D1. The inclined surface FS2 is inclined with respect to the rotation direction of the clutch 40. Specifically, the inclined surface FS2 is inclined so as to be located on one side in the axial direction toward the clockwise direction D1.

As shown in FIGS. 7A and 7B, the clutch 40 includes a disk-shaped base portion 41, a plurality of second protrusions P2, a shaft portion 42, a first wall 43, and an arc wall 44. have. The plurality of second protrusions P2 project from the base portion 41 to the other side in the axial direction. The shaft portion 42, the first wall 43, and the arc wall 44 project from the base portion 41 to one side in the axial direction.

The plurality of second protrusions P2 are arranged in the rotation direction of the coupling 22. The plurality of second protrusions P2 are arranged in an annular shape. Each second protrusion P2 has a first clutch surface FC1 and a second clutch surface FC2. The first clutch surface FC1 is along the axial direction. The second clutch surface FC2 is inclined with respect to the rotation direction of the clutch 40.

The first clutch surface FC1 intersects the rotation direction of the clutch 40. More preferably, the first clutch surface FC1 is orthogonal to the rotation direction of the clutch 40. The first clutch surface FC1 comes into contact with the rotation transmission surface FS1 (see FIG. 6B). Specifically, the first clutch surface FC1 comes into surface contact with the rotation transmission surface FS1.

The second clutch surface FC2 is a surface for moving the clutch 40 from the engaging position to the disengaging position when the clutch 40 rotates clockwise D1. The second clutch surface FC2 is inclined with respect to the rotation direction of the clutch 40. Specifically, the second clutch surface FC2 is inclined so as to approach the base portion 41 toward the clockwise D1. The second clutch surface FC2 comes into contact with the inclined surface FS2 (see FIG. 6B). Specifically, the second clutch surface FC2 comes into surface contact with the inclined surface FS2.

The shaft portion 42 extends from the center of the base portion 41 toward one side in the axial direction of the clutch 40. The shaft portion 42 has a cylindrical shape.

The first wall 43 extends radially outward from the shaft portion 42. The first wall 43 has a first surface 43A and a second surface 43B. The first surface 43A and the second surface 43B are orthogonal to the rotation direction. The first surface 43A faces the downstream side of the counterclockwise D2. The second surface 43B faces the upstream side of the counterclockwise D2. The first surface 43A has a third protrusion 47. The third protrusion 47 protrudes from the first surface 43A. The third protrusion 47 extends along the outer peripheral surface of the shaft portion 42. The third protrusion 47 has a third clutch surface FC3.

The third clutch surface FC3 is a surface for moving the clutch 40 from the engaging position to the disengaging position when the coupling 22 rotates clockwise D1. The third clutch surface FC3 is inclined with respect to the rotation direction of the clutch 40. Specifically, the third clutch surface FC3 is inclined so as to approach the base portion 41 toward the clockwise D1. The third clutch surface FC3 comes into contact with the first coupling surface FP1 (see FIGS. 8B and 10B), which will be described later, when the coupling 22 rotates clockwise D1.

The arc wall 44 extends counterclockwise D2 from the radially outer end of the first wall 43. The arc wall 44 has an arc shape centered on the second axis A2. The outer peripheral surface of the arc wall 44 and the outer peripheral surface of the base portion 41 are flush with each other. The outer peripheral surface of the arc wall 44 and the outer peripheral surface of the base portion 41 are rotatably supported by the inner peripheral surface B12 of the shaft S12 (see FIGS. 6A and 6B). Specifically, the outer peripheral surface of the arc wall 44 and the outer peripheral surface of the base portion 41 are cylindrical surfaces centered on the second axis A2. The inner peripheral surface B12 is a cylindrical surface centered on the second axis A2. The outer peripheral surface of the arc wall 44 and the outer peripheral surface of the base portion 41 are in surface contact with the inner peripheral surface B12 of the shaft S12. As a result, the clutch 40 moves in the direction along the second axis A2 while rotating around the second axis A2.

The first wall 43, the arc wall 44, the third clutch surface FC3, and the third protrusion 47 are each provided symmetrically with respect to the second axis A2.

As shown in FIGS. 8A and 8B, the coupling 22 further has a first cylindrical portion 22D and a second tubular portion 22E shown in FIG. 8B. The first tubular portion 22D and the second tubular portion 22E are cylindrical.

As shown in FIG. 8B, the coupling 22 has a partition wall 22F. The partition wall 22F is located between the second cylindrical portion 22E and the first tubular portion 22D. The partition wall 22F partitions the space in the second tubular portion 22E and the space in the first tubular portion 22D. The first cylindrical portion 22D and the partition wall 22F form a recess 22A. Further, the second cylindrical portion 22E and the partition wall 22F form a second recess 22J. The second tubular portion 22E is fitted into the outer peripheral surface B11 of the shaft S12 (see FIGS. 6A and 6B) and is rotatably supported by the shaft S12.

The coupling 22 has a protruding piece 22G. A pair of projecting pieces 22G are provided symmetrically with respect to the second axis A2. The projecting piece 22G is located in the second recess 22J. The projecting piece 22G projects from the partition wall 22F. The protruding piece 22G has a first coupling surface FP1, a second coupling surface FP2, and a third coupling surface FP3.

The first coupling surface FP1 is a surface for moving the clutch 40 from the engaging position to the disengaging position when the clutch 40 rotates clockwise D1. The first coupling surface FP1 faces the downstream side of the clockwise D1. The first coupling surface FP1 is inclined with respect to the rotation direction of the coupling 22. Specifically, as shown in FIGS. 8 (c) and 8 (d), the first coupling surface FP1 is inclined so as to move away from the partition wall 22F toward the clockwise D1.

The second coupling surface FP2 is a surface for moving the clutch 40 from the disengagement position to the engagement position when the coupling 22 rotates counterclockwise D2. The second coupling surface FP2 faces the downstream side of the counterclockwise D2. The second coupling surface FP2 is inclined with respect to the rotation direction of the coupling 22. Specifically, the second coupling surface FP2 is inclined so as to approach the partition wall 22F toward the counterclockwise D2. The second coupling surface FP2 contacts the end of the first wall 43 of the clutch 40.

The third coupling surface FP3 is a surface that comes into contact with the first wall 43 of the clutch 40 in the rotational direction when the coupling 22 rotates counterclockwise D2. The third coupling surface FP3 is located at a position farther from the partition wall 22F than the second coupling surface FP2. The third coupling surface FP3 intersects the rotation direction of the coupling 22. More preferably, the third coupling surface FP3 is orthogonal to the rotation direction of the coupling 22.

As shown in FIGS. 9 and 10, the first wall 43 of the clutch 40 is located between the protruding pieces 22G of the coupling 22 in the rotational direction. The clutch 40 rotates together with the coupling 22. Therefore, the clutch 40 can rotate together with the coupling 22.
The clutch 40 is movable in the axial direction with respect to the shaft S12. The clutch 40 engages with the engagement position (see FIG. 9) that engages with the first protrusion P1 that is a part of the second gear 32 in the rotational direction and the first protrusion P1 that is a part of the second gear 32. It is possible to move along the axial direction to and from the detachment position (see FIG. 10).

As shown in FIGS. 9A and 9B, the clutch 40 is a part of the second gear 32 by moving the clutch 40 to the engaging position when the coupling 22 rotates counterclockwise D2. The second gear 32 is rotated counterclockwise D2 together with the coupling gear 22B by engaging with the first protrusion P1.

The coupling 22 does not move in the direction away from the side surface 11F of the housing 11 with respect to the shaft S12 by coming into contact with the gear cover 21. Here, "the coupling 22 does not move with respect to the shaft S12" means that it does not move at all, and also means that it moves slightly due to rattling. The clutch 40 described above is also movable in the axial direction with respect to the coupling 22.

To explain the operation at this time more specifically, when the coupling 22 rotates counterclockwise D2 in a state where the clutch 40 is in the disengaged position (see FIGS. 10A and 10B), the coupling 22 The second coupling surface FP2 comes into contact with the end of the second surface 43B of the first wall 43 of the clutch 40 in the rotational direction. As a result, the second coupling surface FP2 inclined with respect to the rotation direction urges the clutch 40 toward the first protrusion P1 of the second gear 32.

The clutch 40 moves to the other side in the axial direction, separates from the second coupling surface FP2, and the second protrusion P2 meshes with the first protrusion P1. Then, each of the first clutch surfaces FC1 of the plurality of second projections P2 comes into contact with each rotation transmission surface FS1 of the plurality of first projections P1. After that, when the coupling 22 rotates slightly counterclockwise to D2, the third coupling surface FP3 comes into contact with the first wall 43 of the clutch 40 in the rotational direction.

As a result, the driving force is transmitted from the coupling 22 to the clutch 40. Further, the driving force to the counterclockwise D2 is transmitted from the clutch 40 to the second gear 32 by each rotation transmission surface FS1. As a result, the coupling 22, the clutch 40, and the second gear 32 are integrated and rotate counterclockwise D2.

On the other hand, as shown in FIGS. 10A and 10B, when the coupling 22 rotates clockwise D1, the clutch 40 is positioned at the disengagement position, so that the second gear 32 It does not engage with the first protrusion P1 and does not rotate the second gear 32 together with the coupling 22.

To explain the operation at this time more specifically, when the coupling 22 rotates clockwise D1 in a state where the clutch 40 is in the engaging position (see FIGS. 9A and 9B), the coupling 22 The first coupling surface FP1 pushes the third clutch surface FC3 of the clutch 40 clockwise to D1. As a result, the clutch 40 rotates clockwise D1 together with the coupling 22.

Then, when the clutch 40 rotates clockwise D1, each second clutch surface FC2 of the plurality of second projections P2 comes into contact with each inclined surface FS2 of the plurality of first projections P1, and the clutch 40 is formed by each inclined surface FS2. Is pushed to one side in the axial direction and moves from the engaged position to the disengaged position. As a result, each second protrusion P2 is axially disengaged from each first protrusion P1. That is, the engagement between each second protrusion P2 and each first protrusion P1 is released. After that, the first coupling surface FP1 of the coupling 22 further presses the third clutch surface FC3 of the clutch 40 toward the disengagement position. As a result, the clutch 40 is positioned at the disengaged position. In this state, since each of the second protrusions P2 is located at an axial distance from each of the first protrusions P1, the rotation of the clutch 40 is not transmitted to the second gear 32. That is, the second gear 32 can rotate independently of the clutch 40.

As shown in FIG. 11, the frame 5A of the drum cartridge 5 has a first side frame 51, a second side frame 52 (see FIG. 12), and a bottom frame 53. The first side frame 51 is located on one side in the axial direction. The second side frame 52 is located on the other side in the axial direction. The bottom frame 53 connects the first side frame 51 and the second side frame 52. The first side frame 51 and the second side frame 52 each have a guide groove 54. The guide groove 54 is fitted with an axial end of the developing roller shaft 12A when the developing cartridge 10 is mounted on the drum cartridge 5.

The developing roller 12 is restricted so that the developing roller shaft 12A does not rotate around the photoconductor drum 5B by entering the guide groove 54. In the developing cartridge 10, the developing roller shaft 12A enters the guide groove 54 and is supported by the frame 5A. As a result, the developing cartridge 10 rotates around the developing roller shaft 12A with respect to the drum cartridge 5 when it is attached to or removed from the drum cartridge 5.

As shown in FIG. 12, the drum cartridge 5 has a frame 5A, a photoconductor drum 5B, a pressing member 5C, an urging member 5D, and a positioning surface 61.

The pressing member 5C presses the developing roller 12 against the photoconductor drum 5B. The urging member 5D urges the pressing member 5C toward the photoconductor drum 5B. In the developing roller 12, when the developing cartridge 10 is mounted on the drum cartridge 5, the second contact surface 81 described later of the developing cartridge 10 is pressed toward the photoconductor drum 5B by the pressing member 5C, so that the photoconductor 12 is a photoconductor. Pressed by the drum 5B. The pressing member 5C and the urging member 5D are located on one side and the other side of the frame 5A in the axial direction, respectively.

The positioning surface 61 determines the position of the developing cartridge 10 with respect to the drum cartridge 5 while supporting the developing cartridge 10 in a state where the developing cartridge 10 is mounted on the drum cartridge 5. The positioning surface 61 is made of a magnet. Specifically, the positioning surface 61 is made of a permanent magnet 60. The permanent magnet 60 is fixed to the bottom frame 53. In other words, the drum cartridge 5 has a permanent magnet 60 fixed to the frame 5A. The permanent magnet 60 has a positioning surface 61. The permanent magnets 60 are located on one side and the other side of the frame 5A in the axial direction. That is, the positioning surface 61 is located on one side and the other side of the frame 5A in the axial direction.

The developing cartridge 10 further includes a magnetic member 70, a first contact surface 71, and a second contact surface 81.

The magnetic member 70 generates a magnetic force in the developing cartridge 10 in a direction approaching the drum cartridge 5 in a state where the developing cartridge 10 is mounted on the drum cartridge 5. Specifically, the magnetic member 70 generates a magnetic force on the developing cartridge 10 in the direction in which the first contact surface 71 approaches the positioning surface 61.

The magnetic member 70 is a cylindrical roller that can rotate about the third axis A3 extending in the axial direction. The magnetic member 70 is rotatably supported by the housing 11. Specifically, the housing 11 has a shaft S70 protruding in the axial direction. The magnetic member 70 is rotatably supported by the shaft S70. The magnetic member 70 is made of a magnetic material. Specifically, the magnetic member 70 is made of a ferromagnetic material. As an example, the magnetic member 70 is made of a metal having ferromagnetism such as iron.

The first contact surface 71 is an outer peripheral surface of the magnetic member 70. That is, the first contact surface 71 is the outer peripheral surface of the roller. The first contact surface 71 can come into contact with the positioning surface 61 of the drum cartridge 5 in a state where the developing cartridge 10 is mounted on the drum cartridge 5. The first contact surface 71 is located on the positioning surface 61 in a state where the developing cartridge 10 is mounted on the image forming apparatus 1 together with the drum cartridge 5. That is, the first contact surface 71 can come into contact with the positioning surface 61 from above.

Similar to the positioning surface 61, the magnetic member 70 and the first contact surface 71 are located on one side and the other side of the housing 11 in the axial direction. Specifically, the housing 11 has a shaft S70 protruding from the side surface 11F on one side in the axial direction to one side in the axial direction, and the housing 11 protruding from the side surface 11G on the other side in the axial direction (see FIG. 3) to the other side in the axial direction. It has a shaft (not shown). Each shaft S70 rotatably supports the magnetic member 70. The outer peripheral surface of each magnetic member 70 is the first contact surface 71.

The second contact surface 81 receives a pressing force for pressing the developing roller 12 against the photoconductor drum 5B. Specifically, the second contact surface 81 receives pressing pressure from the pressing member 5C in a state where the developing cartridge 10 is mounted on the drum cartridge 5. The second contact surface 81 is in contact with the pressing member 5C. The second contact surface 81 is located on one side and the other side of the housing 11 in the axial direction, similarly to the pressing member 5C. Specifically, the housing 11 has protrusions 11E protruding outward in the axial direction from the side surfaces 11F and 11G (see FIG. 3), respectively (only one is shown). The surface of each protrusion 11E facing the pressing member 5C is the second contact surface 81.

As shown in FIG. 13A, in the coupling 22, when the developing cartridge 10 is mounted on the drum cartridge 5 and the coupling 22 rotates clockwise D1, the developing cartridge 10 is attached to the drum cartridge 5. The first moment M1 in the approaching direction is generated. Specifically, the coupling 22 generates a first moment M1 in a direction in which the first contact surface 71 approaches the positioning surface 61 when the coupling 22 rotates clockwise D1. The first moment M1 is a force that causes the developing cartridge 10 to rotate clockwise.

On the other hand, as shown in FIG. 13B, the coupling 22 generates a second moment M2 in the direction in which the developing cartridge 10 separates from the drum cartridge 5 when the coupling 22 rotates counterclockwise D2. Specifically, the coupling 22 generates a second moment M2 in a direction in which the first contact surface 71 moves away from the positioning surface 61 when the coupling 22 rotates counterclockwise D2. The second moment M2 is a force that causes the developing cartridge 10 to rotate counterclockwise.

The second contact surface 81 is oriented so as to generate a moment M13 in the developing cartridge 10 in a direction in which the first contact surface 71 approaches the positioning surface 61 when a pressing force is received from the pressing member 5C. Specifically, the second contact surface 81 is oriented so that the pressing force FP of the pressing member 5C is displaced toward the side where the positioning surface 61 is located with respect to the plane PL. The plane PL is a plane that passes through the second contact surface 81 and the first axis A1. As a result, when the developing cartridge 10 is mounted on the image forming apparatus 1, the pressing force FP of the pressing member 5C is not applied toward the first axis A1. The pressing force FP of the pressing member 5C is applied downward of the first axis A1.

As a result, when the second contact surface 81 receives the pressing force from the pressing member 5C, a moment M13 is generated in the developing cartridge 10 so as to cause a clockwise rotation around the vicinity of the developing roller shaft 12A. .. That is, a moment M13 is generated in the developing cartridge 10 in the direction in which the first contact surface 71 approaches the positioning surface 61.

When the coupling 22 rotates counterclockwise D2, the sum of the moment M11, the moment M12, and the moment M13 is larger than the second moment M2. The moment M11 is a moment in the direction in which the first contact surface 71 generated by the magnetic force between the magnetic member 70 and the permanent magnet 60 approaches the positioning surface 61. The moment M12 is a moment in the direction in which the first contact surface 71 generated by the weight of the developing cartridge 10 approaches the positioning surface 61. The moment M13 is a moment in the direction in which the first contact surface 71 generated by the pressing force FP received from the pressing member 5C by the second contact surface 81 approaches the positioning surface 61. Further, when the coupling 22 rotates counterclockwise D2, the sum of the moment M11 and the moment M12 is larger than the second moment M2.

For example, when the amount of toner contained in the housing 11 is larger than the predetermined amount and the developing cartridge 10 is heavier than the predetermined amount, as in the case where the developing cartridge 10 is in a new state, the sum of the moments M11 and M12. Is greater than the second moment M2. On the other hand, even when the amount of toner contained in the housing 11 is equal to or less than a predetermined amount and the developing cartridge 10 is lighter than the predetermined amount, as in the case where the developing cartridge 10 is in a state immediately before replacement, at least, at least. The sum of the moments M11, M12, and M13 is larger than the second moment M2.

Next, the operation of each member when the coupling 22 rotates clockwise D1 or counterclockwise D2 will be described. In FIGS. 14 and 15, the magnetic member 70, the first contact surface 71, and the second contact surface 81 are not shown.

As shown in FIGS. 14A and 14B, when the control unit CU controls the motor 8 to rotate the joint 7 (see FIG. 1) clockwise D1, the coupling gear 22B (coupling 22) watches. Rotate to D1. In this case, the moving gear 33 rotates (revolves) clockwise together with the coupling gear 22B to be located at the second position and meshes with the small diameter gear 31B of the first gear 31. As a result, as the coupling gear 22B rotates clockwise D1, the moving gear 33 rotates counterclockwise due to meshing with the coupling gear 22B, and the first gear 31 rotates counterclockwise due to meshing with the moving gear 33. Rotate clockwise.

When the first gear 31 rotates clockwise, the first idle gear 34 rotates counterclockwise. The second idle gear 35 that meshes with the first idle gear 34 rotates clockwise. Then, the second idle gear 35, the developing roller gear 23, and the supply roller gear 24 rotate counterclockwise. As a result, the developing roller 12 and the supply roller 13 rotate counterclockwise. Further, the first agitator 14 that rotates together with the first gear 31 also rotates.

In this way, when the coupling 22 rotates clockwise D1, the first agitator 14, the developing roller 12, and the supply roller 13 can be rotated to form an image.

Since the moving gear 33 is located at the second position, the moving gear 33 does not mesh with the transport gear 26. Therefore, the conveyor gear 26 does not rotate, nor does the third idle gear 36, the fourth idle gear 37, and the agitator gear 25 rotate. As a result, the auger 16 and the second agitator 15 do not rotate, and the toner T is not conveyed from the toner storage chamber 11B to the developing chamber 11A.

At this time, since the clutch 40 does not engage with the first protrusion P1 (see FIG. 10) which is a part of the second gear 32, the second gear 32 does not rotate depending on the engagement with the clutch 40. However, the second gear 32 rotates counterclockwise as the first gear 31 rotates clockwise due to meshing with the first gear 31.

As shown in FIG. 13A, when the coupling 22 rotates clockwise D1, the first moment M1 in the direction in which the first contact surface 71 approaches the positioning surface 61 acts on the developing cartridge 10. In addition to this, the moment M11 generated by the magnetic force, the moment M12 generated by the weight of the developing cartridge 10, and the moment M13 generated by the pressing force received by the second contact surface 81 act on the developing cartridge 10. ..

As a result, the developing cartridge 10 is urged toward the drum cartridge 5 when the coupling 22 rotates clockwise D1. Specifically, in the developing cartridge 10, when the coupling 22 rotates clockwise D1, the first contact surface 71 is urged to the positioning surface 61. As a result, the developing cartridge 10 is positioned with respect to the drum cartridge 5 in a state where the first contact surface 71 is in contact with the positioning surface 61.

On the other hand, as shown in FIGS. 15A and 15B, when the control unit CU controls the motor 8 to rotate the joint 7 counterclockwise D2, the coupling gear 22B (coupling 22) turns counterclockwise. Rotate to D2. In this case, the moving gear 33 rotates (revolves) counterclockwise together with the coupling gear 22B and is located at the first position, and does not mesh with the first gear 31. Then, as the coupling gear 22B rotates counterclockwise D2, the second gear 32 rotates counterclockwise D2 together with the coupling gear 22B via the clutch 40. Then, the first gear 31 rotates clockwise due to meshing with the second gear 32.

When the first gear 31 rotates clockwise, the developing roller gear 23 and the supply roller gear 24 are counterclockwise via the first idle gear 34 and the second idle gear 35, as in the case where the coupling gear 22B rotates clockwise D1. Rotate clockwise. As a result, the developing roller 12 and the supply roller 13 rotate counterclockwise. Further, the first agitator 14 that rotates together with the first gear 31 also rotates.

In this way, when the coupling 22 rotates counterclockwise D2, the first agitator 14, the developing roller 12, and the supply roller 13 can be rotated to form an image.

Then, when the moving gear 33 is located at the first position, the moving gear 33 meshes with the transport gear 26. Therefore, the conveyor gear 26 rotates counterclockwise. When the conveyor gear 26 rotates counterclockwise, the third idle gear 36 rotates clockwise. When the third idle gear 36 rotates clockwise, the fourth idle gear 37 rotates counterclockwise. When the fourth idle gear 37 rotates counterclockwise, the agitator gear 25 rotates clockwise.

As described above, when the coupling 22 rotates counterclockwise D2, the conveyor gear 26, the third idle gear 36, the fourth idle gear 37, and the agitator gear 25 rotate. As a result, the auger 16 and the second agitator 15 rotate, and the toner T can be conveyed from the toner accommodating chamber 11B to the developing chamber 11A. That is, when the coupling 22 rotates clockwise D1, the toner T can be conveyed from the toner accommodating chamber 11B to the developing chamber 11A while forming an image.

As shown in FIG. 13B, when the coupling 22 rotates counterclockwise D2, a second moment M2 in the direction in which the first contact surface 71 is separated from the positioning surface 61 is generated in the developing cartridge 10. On the other hand, in the developing cartridge 10, a moment M11 is generated in the direction in which the first contact surface 71 generated by the magnetic force approaches the positioning surface 61. Further, in the developing cartridge 10, a moment M12 is generated in the direction in which the first contact surface 71 generated by the weight of the developing cartridge 10 approaches the positioning surface 61. Further, a moment M13 in the direction in which the first contact surface 71 generated by the pressing force received by the second contact surface 81 approaches the positioning surface 61 acts on the developing cartridge 10.

Since the sum of the moments M11 and M12 or the sum of the moments M11, M12 and M13 is larger than the second moment M2, the developing cartridge 10 has a second rotation when the coupling 22 rotates counterclockwise D2. It resists the moment M2 and is urged toward the drum cartridge 5 by magnetic force or the like. Specifically, in the developing cartridge 10, when the coupling 22 rotates counterclockwise D2, the first contact surface 71 resists the second moment M2 and the first contact surface 71 is positioned by the moments M11, M12, M13 generated by magnetic force or the like. It is urged to approach 61.

As a result, in the developing cartridge 10, even when the coupling 22 rotates counterclockwise D2, the first contact surface 71 is urged to the positioning surface 61 without being separated from the positioning surface 61. As a result, the developing cartridge 10 is maintained in a state in which the positioning surface 61 is in contact with the positioning surface 61 and positioned with respect to the drum cartridge 5 even when the coupling 22 rotates counterclockwise D2.

According to the first embodiment described above, the following effects can be obtained.
In the developing cartridge 10, the direction of the moments (M1, M2) applied to the developing cartridge 10 changes depending on whether the coupling 22 rotates clockwise or counterclockwise. However, when the coupling 22 rotates counterclockwise, the developing cartridge 10 resists the second moment M2 and is urged in a direction in which the first contact surface 71 approaches the positioning surface 61 of the drum cartridge 5 by magnetic force or the like. To. This makes it possible to prevent the developing cartridge 10 from moving. Specifically, it is possible to suppress the movement of the first contact surface 71 in the direction away from the positioning surface 61. As a result, it is possible to prevent the position of the developing cartridge 10 from shifting.

Further, the magnetic member 70 is located on one side and the other side of the housing 11 in the axial direction. As a result, it is possible to further suppress the position of the developing cartridge 10 from being displaced due to the magnetic force generated by the magnetic members 70 located on both sides of the housing 11 in the axial direction.

Further, since the first contact surface 71 is located on one side and the other side of the housing 11 in the axial direction, the positioning surface 61 enables stable support of the developing cartridge 10.

Further, the first contact surface 71 is located on the positioning surface 61 in a state where the developing cartridge 10 is mounted on the image forming apparatus 1. As a result, in addition to the moment M11 generated by the magnetic force, the moment M12 generated by the weight of the developing cartridge 10 can further suppress the position of the developing cartridge 10.

Further, the first contact surface 71 is an outer peripheral surface of a rotatable cylindrical magnetic member 70 (roller). As a result, the rotation of the magnetic member 70 can prevent the friction generated by the contact between the first contact surface 71 and the positioning surface 61 from affecting the pressing load of the pressing member 5C.

Further, the second contact surface 81 generates a moment M13 in the developing cartridge 10 in the direction in which the first contact surface 71 approaches the positioning surface 61 when a pressing force is received from the pressing member 5C. As a result, in addition to the moment M11 generated by the magnetic force, the moment M13 generated by the pressing force can further suppress the position of the developing cartridge 10.

Further, in the developing cartridge 10, the first gear 31 is rotated clockwise and the developing roller 12 is rotated in the same direction regardless of whether the coupling 22 is rotated clockwise D1 or counterclockwise D2. Can be made to. Therefore, even when the coupling 22 is rotated in both the clockwise direction D1 and the counterclockwise direction D2, the developing roller 12 does not reverse, so that toner leakage is unlikely to occur.

Further, the moving gear 33 has a large diameter gear 33B and a small diameter gear 33A that rotate together, the large diameter gear 33B meshes with the first gear 31, the small diameter gear 33A meshes with the coupling gear 22B, and the second gear 32. Has a larger diameter than the coupling gear 22B. Therefore, when the coupling 22 is rotated clockwise D1, the speed is increased by the moving gear 33 to rotate the first gear 31. On the other hand, when the coupling 22 is rotated counterclockwise D2, the speed is increased by the second gear 32 to rotate the first gear 31. Therefore, the difference in speed of the developing roller 12 can be reduced between the case where the coupling 22 is rotated clockwise D1 and the case where the coupling 22 is rotated counterclockwise D2.

Further, in the developing cartridge 10, the developing roller 12 can be rotated by rotating the coupling 22 clockwise D1, and the toner T can be supplied by rotating the coupling 22 counterclockwise D2. Therefore, the toner T can be supplied from the toner accommodating chamber 11B to the developing chamber 11A at a required timing only by the operation of the coupling 22. Therefore, since other parts such as the conventional lever are unnecessary, the developing cartridge 10 can be miniaturized.

Further, in the developing cartridge 10, the first gear 31 is rotated counterclockwise and the developing roller 12 is rotated in the same direction regardless of whether the coupling 22 is rotated clockwise D1 or counterclockwise D2. Can be turned. Therefore, it is possible to supply the toner T from the toner accommodating chamber 11B to the developing chamber 11A while developing.

Although the first embodiment of the present disclosure has been described above, the present disclosure is not limited to the first embodiment, and can be appropriately modified and carried out as illustrated below. In the following description, the same reference numerals will be given to the same points as those of the above-described embodiment, and the description thereof will be omitted as appropriate.

In the first embodiment, the developing cartridge 10 is provided with rollers, and the drum cartridge 5 is provided with a magnet for attracting the rollers, but the present invention is not limited to this, and contrary to the first embodiment, the drum cartridge 5 is provided with rollers. , The developing cartridge 10 may include a magnet.

For example, in the second embodiment shown in FIG. 16, the developing cartridge 10 includes a magnetic member 170 made of a magnet instead of the magnetic member 70 (roller) made of the magnetic material of the first embodiment. Further, the drum cartridge 5 includes a roller 160 made of a magnetic material instead of the permanent magnet 60 of the first embodiment. The roller 160 has a positioning surface 161.

The roller 160 is a cylindrical member. The roller 160 is rotatable about the third axis A3 extending in the axial direction when the developing cartridge 10 is mounted on the drum cartridge 5. The roller 160 is rotatably supported by the frame 5A. Specifically, the frame 5A has a shaft 5S extending in the axial direction. The roller 160 is rotatably supported by the shaft 5S. The roller 160 is made of a ferromagnet. As an example, the roller 160 is made of a metal having ferromagnetism such as iron. The positioning surface 161 is an outer peripheral surface of the roller 160. The rollers 160 and the positioning surface 161 are located on one side and the other side of the frame 5A in the axial direction, respectively.

The magnetic member 170 is made of a permanent magnet. The magnetic member 170 is fixed to the housing 11. The magnetic member 170 has a first contact surface 171 that can come into contact with the positioning surface 161. The magnetic member 170 and the first contact surface 171 are located on one side and the other side of the housing 11 in the axial direction, similarly to the positioning surface 161.

Even with such a configuration, when the coupling 22 rotates counterclockwise D2, the developing cartridge 10 resists the second moment M2, and the first contact surface is formed by the moments M11, M12, and M13 generated by magnetic force or the like. Since the 171 is urged in the direction approaching the positioning surface 161 it is possible to prevent the development cartridge 10 from being displaced.

Further, since the positioning surface 161 is the outer peripheral surface of the roller 160, the rotation of the roller 160 affects the pressing load of the pressing member 5C due to the friction generated by the contact between the first contact surface 171 and the positioning surface 161. Can be suppressed.

In the first embodiment, when the developing cartridge 10 is mounted on the drum cartridge 5, the magnetic member 70 made of a magnetic material and the positioning surface 61 made of a magnet are in contact with each other. Further, in the second embodiment, the magnetic member 170 made of a magnet and the positioning surface 161 made of a magnetic material are in contact with each other. However, the present invention is not limited to this, and the magnetic material and the magnet may be non-contact.

For example, in the third embodiment shown in FIGS. 17A and 17B, the developing cartridge 10 further includes ribs 270 with respect to the second embodiment. The rib 270 projects axially from the side surfaces 11F and 11G (see FIG. 3) of the housing 11 in the axial direction. The rib 270 is U-shaped and forms a recess 272. The magnetic member 170 is made of a magnet. Specifically, the magnetic member 170 is made of a permanent magnet. The magnetic member 170 is fixed to the housing 11 in a state of being inserted into the recess 272 of the rib 270.

The rib 270 is sandwiched between the roller 160 and the magnetic member 170 in a state where the developing cartridge 10 is mounted on the drum cartridge 5. Specifically, the rib 270 is sandwiched between the positioning surface 161 and the magnetic member 170. The rib 270 has a first contact surface 271 that can contact the positioning surface 161. The magnetic member 170 urges the rib 270 by magnetic force in the direction in which the first contact surface 271 contacts the positioning surface 161. Since the rib 270 is located between the positioning surface 161 and the magnetic member 170, the positioning surface 161 and the magnetic member 170 do not come into contact with each other.

Even with such a configuration, when the coupling 22 rotates counterclockwise D2, the developing cartridge 10 resists the second moment M2, and the first contact surface 271 is positioned by the moment M11 generated by the magnetic force. Since it is urged in the direction approaching 161 it is possible to suppress the position of the developing cartridge 10 from shifting.

In the third embodiment, there is a rib 270 between the magnet and the magnetic material, but the present invention is not limited to this. For example, when the first contact surface and the positioning surface are located away from the magnet (magnetic member 170) and the magnetic body (roller 160), there may be an empty space between the magnet and the magnetic body.

Further, in the third embodiment, the developing cartridge 10 is provided with a magnet and the drum cartridge 5 is provided with a magnetic material, but the present invention is not limited thereto. That is, the developing cartridge 10 may be provided with a magnetic material, and the drum cartridge 5 may be provided with a magnet.

In the first embodiment, as shown in FIG. 12, the magnetic member 70 is located below the first gear 31, but the present invention is not limited to this. For example, in the fourth embodiment shown in FIG. 18, the magnetic member 70 is located below the agitator gear 25. In other words, the magnetic member 70 is located farther from the developing roller 12 than the coupling 22. According to this, it is possible to suppress the position of the developing cartridge 10 from being displaced even if the magnetic force is small, as compared with the case where the magnetic member 70 is located closer to the developing roller 12 than the coupling 22.

In the first embodiment, the drum cartridge 5 has a positioning surface 61, but the present invention is not limited to this. For example, as shown in FIG. 18, the image forming apparatus 1 may have a positioning surface 61.

In this case, the coupling 22 is the first in the direction in which the developing cartridge 10 approaches the image forming apparatus 1 when the developing cartridge 10 is rotated clockwise D1 while the developing cartridge 10 is attached to the image forming apparatus 1. Generate a moment M1. Further, the coupling 22 generates a second moment M2 in the direction in which the developing cartridge 10 moves away from the image forming apparatus 1 or the image forming apparatus 1 when the coupling 22 rotates counterclockwise D2. Specifically, the coupling 22 generates a first moment M1 in a direction in which the first contact surface 71 approaches the positioning surface 61 when rotating clockwise D1. Further, when the coupling 22 rotates counterclockwise D2, the coupling 22 generates a second moment M2 in a direction in which the first contact surface 71 is separated from the positioning surface 61.

The magnetic member 70 generates a magnetic force in the developing cartridge 10 in a direction approaching the image forming apparatus 1. Specifically, the magnetic member 70 generates a magnetic force on the developing cartridge 10 in the direction in which the first contact surface 71 approaches the positioning surface 61. The first contact surface 71 is in contact with the positioning surface 61 of the image forming apparatus 1.

When the coupling 22 rotates counterclockwise D2, the developing cartridge 10 resists the second moment M2 and is urged toward the image forming apparatus 1 by the magnetic force. Specifically, when the coupling 22 rotates counterclockwise D2, the developing cartridge 10 resists the second moment M2, and the first contact surface 71 approaches the positioning surface 61 due to the moment M11 generated by the magnetic force or the like. Be urged.

In the first embodiment, the developing cartridge 10 is configured separately from the drum cartridge 5, but the development cartridge is not limited to this, and the developing cartridge may be configured integrally with the drum cartridge. That is, the developing cartridge may include a photoconductor drum.

Further, in the first embodiment, in the developing cartridge 10, the portion constituting the toner accommodating chamber 11B is integrally configured with the portion constituting the developing chamber 11A, but the present invention is not limited to this. For example, in the developing cartridge, the portion constituting the toner accommodating chamber is configured separately from the portion constituting the developing chamber, and the portion constituting the toner accommodating chamber is configured to be detachable from the portion constituting the developing chamber. You may be. That is, the drum cartridge, the developing cartridge (the portion constituting the developing chamber), and the portion constituting the toner accommodating chamber may be separate bodies.

In the first embodiment, the moving gear 33 has a small diameter gear 33A and a large diameter gear 33B having different sizes, but may have only one gear. In this case, it is sufficient that one gear can mesh with the coupling gear 22B and also with the first gear 31.

In the first embodiment, the second gear 32 includes a plurality of first protrusions P1, and the clutch 40 includes a plurality of second protrusions P2, but is not limited thereto. For example, the second gear 32 may include one first protrusion. Further, the clutch 40 may include one second protrusion. Further, the first protrusion P1 includes, but is not limited to, a rotation transmission surface FS1 and an inclined surface FS2. For example, one protrusion may include a rotation transmission surface. Further, a protrusion different from one protrusion may have an inclined surface. Similarly, one protrusion may include a first clutch surface. Further, a protrusion different from the one protrusion may be provided with the second clutch surface.

In the first embodiment, both the inclined surface FS2 and the second clutch surface FC2 are inclined surfaces inclined with respect to the rotation direction, but the present invention is not limited to this, and either the inclined surface or the second clutch surface is used. It may be an inclined surface.

In the first embodiment, the coupling 22 includes two surfaces (FP1) for moving the clutch 40 toward the disengagement position, but the coupling 22 is not limited to this, and the clutch 40 is moved toward the disengagement position. The surface may be one, or may be three or more.

In the first embodiment, both the first coupling surface FP1 and the third clutch surface FC3 are inclined surfaces inclined with respect to the rotation direction, but the first coupling surface and the third clutch are not limited to this. One of the surfaces may be an inclined surface.

In the first embodiment, the drum cartridge 5 is provided with the pressing member 5C, but the present invention is not limited to this, and the image forming apparatus 1 may be provided with the pressing member.

In the first embodiment, the member transported from the toner storage chamber 11B to the developing chamber 11A is the auger 16, but the member is not limited to this and may be an agitator. In this case, the transport gear can be made rotatable together with the agitator.

In the first embodiment, the first contact surface 71 is located on the positioning surface 61 in the state where the developing cartridge 10 is mounted on the image forming apparatus 1, but the present invention is not limited to this. For example, the first contact surface may be located in front of the positioning surface when the developing cartridge is mounted on the image forming apparatus.

In the first embodiment, the contact between the first contact surface and the positioning surface is the contact between the outer peripheral surface of the rotatable roller and the flat surface so as not to affect the pressing load of the pressing member 5C. Not limited to. For example, the contact between the first contact surface and the positioning surface may be a contact between planes, that is, a surface contact.

In the first embodiment, the magnetic member 70 has a first contact surface 71. Further, in the third embodiment, the first contact surface 271 is located near the magnetic member 170. However, it is not limited to this. That is, the developing cartridge may have a structure in which the first contact surface is formed separately from the magnetic member and is located away from the magnetic member.

In each of the above embodiments, one of the developing cartridge and the drum cartridge (or image forming apparatus) is provided with a magnet and the other is provided with a magnetic material, but the present invention is not limited thereto. That is, the developing cartridge and the drum cartridge (or the image forming apparatus) may each include a magnet. For example, the developing cartridge may have a structure in which the magnetic member having the first contact surface is made of a magnet, and the positioning surface with which the first contact surface can be contacted is also made of a magnet.

In the first embodiment, the monochrome image forming apparatus 1 is exemplified as the image forming apparatus, but the image forming apparatus may be a color image forming apparatus, may be exposed by an LED, or may be a copy. It may be a machine or a multifunction device.

Each element of each of the above-described embodiments and modifications can be implemented in any combination.

1 Image forming device 5 Drum cartridge 10 Developing cartridge 12 Developing roller 22 Coupling 61 Positioning surface 70 Magnetic member 71 First contact surface A1 First axis A2 Second axis

Claims (18)

It ’s a developing cartridge,
A developing roller that is rotatable about the first axis extending in the axial direction,
A coupling that can rotate in both the first rotation direction and the second rotation direction opposite to the first rotation direction for the second axis extending in the axial direction, and the development cartridge is mounted on the image forming apparatus or the drum cartridge. In this state, when the coupling rotates in the first rotation direction, the developing cartridge generates a first moment in a direction approaching the image forming apparatus or the drum cartridge, and the coupling causes the second rotation. A coupling that generates a second moment in the direction in which the developing cartridge separates from the image forming apparatus or the drum cartridge when rotating in the rotation direction.
The developing cartridge is provided with the image forming apparatus or a magnetic member that generates a magnetic force in a direction approaching the drum cartridge.
The developing cartridge is characterized in that when the coupling rotates in the second rotation direction, it resists the second moment and is urged by the magnetic force in a direction approaching the image forming apparatus or the drum cartridge. Development cartridge. The developing cartridge according to claim 1, wherein the magnetic member is located farther from the developing roller than the coupling. The developing cartridge further comprises a housing capable of accommodating toner.
The developing cartridge according to claim 1 or 2, wherein the magnetic member is located on one side and the other side of the housing in the axial direction. The developing cartridge further comprises a first contact surface accessible to the positioning surface of the image forming apparatus or the drum cartridge.
In the coupling, when the development cartridge is mounted on the image forming apparatus or the drum cartridge and the coupling rotates in the first rotation direction, the first contact surface approaches the positioning surface. The first moment in the direction is generated, and when the coupling rotates in the second rotation direction, the second moment in the direction in which the first contact surface separates from the positioning surface is generated.
The developing cartridge is characterized in that when the coupling rotates in the second rotation direction, the first contact surface is urged in a direction approaching the positioning surface by the magnetic force against the second moment. The developing cartridge according to any one of claims 1 to 3. The developing cartridge further comprises a housing capable of accommodating toner.
The developing cartridge according to claim 4, wherein the first contact surface is located on one side and the other side of the housing in the axial direction. The developing cartridge according to claim 4 or 5, wherein the first contact surface is located on the positioning surface in a state where the developing cartridge is mounted on the image forming apparatus. When the coupling rotates in the second rotation direction, the moment in the direction in which the first contact surface generated by the magnetic force approaches the positioning surface and the first contact surface generated by the weight of the developing cartridge are the same. The developing cartridge according to claim 6, wherein the sum with the moment in the direction approaching the positioning surface is larger than the second moment. The developing cartridge according to claim 6, wherein the developing cartridge can be attached to a drum cartridge having a photoconductor drum and the positioning surface. The developing cartridge further comprises a second contact surface that receives a pressing force for pressing the developing roller against the photoconductor drum.
The developing cartridge according to claim 8, wherein the first contact surface or the positioning surface is an outer peripheral surface of a roller that is rotatable about a third axis extending in the axial direction. The developing cartridge according to claim 9, wherein the second contact surface generates a moment in the developing cartridge in a direction in which the first contact surface approaches the positioning surface when a pressing force is applied. When the coupling rotates in the second rotation direction, the moment in the direction in which the first contact surface generated by the magnetic force approaches the positioning surface and the first contact surface generated by the weight of the developing cartridge are the same. The sum of the moment in the direction approaching the positioning surface and the moment in the direction in which the first contact surface approaches the positioning surface generated by the pressing force applied to the second contact surface is larger than the second moment. The developing cartridge according to claim 10. The magnetic member is the roller made of a magnetic material.
The first contact surface is an outer peripheral surface of the roller.
The developing cartridge according to any one of claims 9 to 11, wherein the positioning surface is made of a magnet. The positioning surface is an outer peripheral surface of the roller made of a magnetic material.
The developing cartridge according to any one of claims 9 to 11, wherein the magnetic member has the first contact surface and is made of a magnet. The developing cartridge is a rib having the first contact surface, further comprising a rib sandwiched between the positioning surface and the magnetic member.
The method according to any one of claims 4 to 11, wherein the magnetic member is made of a magnet and the rib is urged by a magnetic force in a direction in which the first contact surface contacts the positioning surface. Development cartridge. The coupling has a coupling gear for rotating the developing roller.
The developing cartridge is
With the housing
A developing chamber located inside the housing, which can accommodate toner for supplying the developing rollers, and a developing chamber.
A toner storage chamber located inside the housing, which can store toner for supplying to the developing room, and a toner storage chamber.
An auger or agitator capable of supplying the toner in the toner accommodating chamber to the developing chamber, the auger or agitator rotating about the auger axis extending in the axial direction.
With a transfer gear that can rotate with the auger or the agitator,
In a moving gear that meshes with the coupling gear and can rotate in both the first rotation direction and the second rotation direction, the first position that meshes with the transfer gear and the transfer in a state of meshing with the coupling gear. A moving gear that can move between a second position that does not mesh with the gear, and is located at the first position when the coupling gear rotates in the second rotation direction, and the coupling gear is the first rotation. The moving gear located at the second position when rotating in the direction,
The developing cartridge according to any one of claims 1 to 14, further comprising. The first gear for rotating the developing roller and
A second gear that meshes with the first gear and is rotatable in the second rotation direction with respect to the second axis.
A clutch that is located between the coupling and the second gear in the axial direction and rotates together with the coupling, and is one of the second gears when the coupling rotates in the second rotation direction. Engage with the portion, rotate the second gear together with the coupling gear in the second rotation direction, and when the coupling rotates in the first rotation direction, engage with a part of the second gear. A clutch that does not rotate the second gear together with the coupling,
Equipped with
When the coupling gear rotates in the second rotation direction,
The moving gear is located in the first position and does not mesh with the first gear.
In response to the coupling gear rotating in the second rotation direction, the second gear rotates in the second rotation direction together with the coupling gear via the clutch, and the first gear is the first gear. By engaging with the 2 gears, it rotates in the first rotation direction and
When the coupling gear rotates in the first rotation direction,
The moving gear is located in the second position and meshes with the first gear.
In response to the coupling gear rotating in the first rotation direction, the moving gear rotates in the second rotation direction due to meshing with the coupling gear, and the first gear is connected to the moving gear. The developing cartridge according to claim 15, wherein the developing cartridge rotates in the first rotation direction by meshing. When the coupling gear rotates in the first rotation direction, the clutch does not engage with a part of the second gear, and the second gear meshes with the first gear so that the first gear is the first gear. The developing cartridge according to claim 16, wherein the developing cartridge rotates in the second rotation direction according to the rotation in one rotation direction. The clutch is movable along the axial direction between an engagement position that engages with a part of the second gear and a disengagement position that does not engage with the part of the second gear. The developing cartridge according to claim 16 or 17.

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