CN105676607B

CN105676607B - Developing cartridge

Info

Publication number: CN105676607B
Application number: CN201610200592.0A
Authority: CN
Inventors: 李争光; 杨晓锋
Original assignee: Print Rite Unicorn Image Products Co Ltd
Current assignee: Print Rite Unicorn Image Products Co Ltd
Priority date: 2016-03-31
Filing date: 2016-03-31
Publication date: 2023-08-11
Anticipated expiration: 2036-03-31
Also published as: CN105676607A

Abstract

The invention relates to a developing box, and belongs to the technical field of electrophotographic imaging printing. The developing device comprises a box body, a developing unit and a driving switching unit, wherein the driving switching unit comprises a reset piece, a connecting control piece, a developing rotary force receiving piece and a transmission gear for transmitting rotary force to a developing roller. The development rotary force receiving piece is connected with a development device drive output component on the host machine during development operation and is disconnected with the development device drive output component during non-development by matching the components of the drive switching unit with the development end cover and the drive end cover, so that the function of switching the drive of the development roller is realized. The drive switching unit in the developing box has a simple structure, and is convenient to manufacture and assemble, so that the manufacturing cost of the developing box is saved.

Description

Developing cartridge

Technical Field

The present invention relates to a developing cartridge detachably mountable to an electrophotographic image forming apparatus.

Background

An electrophotographic image forming apparatus is an apparatus for forming an image on a printing medium such as paper using an electrophotographic principle, and includes a copying machine, a printer, a facsimile machine, an all-in-one machine, etc., generally including a main body and a developing cartridge detachably mounted in the main body; among them, the developing cartridge has at least a developing roller that supplies developer onto a photosensitive drum to develop an electrostatic latent image, and generally also has a photosensitive drum for forming an electrostatic image.

An electrophotographic image forming apparatus and a developing cartridge detachably mountable to the electrophotographic image forming apparatus are disclosed in patent document publication No. CN104541212 a.

As shown in fig. 41 of the specification thereof, the main unit of the electrophotographic image forming apparatus has a drum driving output member 61 and a developing device driving output member 62 which receive rotational force from a driving motor in the main unit and output the rotational force to a drum rotational force receiving member 4a and a developing rotational force receiving member 474 provided on the developing cartridge as shown in fig. 43; as shown in fig. 7 of the specification thereof, the main machine further has a main machine pushing member 80 for applying a pushing force in the F1 direction to the developing unit 9 so as to rotate about the rotation axis X with respect to the drum unit 8.

As shown in fig. 43 to 53 of the specification, the developing cartridge is provided with a drive switching device for switching the drive of the developing roller 6, for receiving a rotational force from the developing device drive output member 62 and rotationally driving the developing roller during a developing operation, and cutting off the drive to the developing roller during a non-developing period, thereby stopping the developing roller from continuing to supply toner to the photosensitive drum during the non-developing period. The drive switching device includes a developing rotary force receiving member 474, a coupling control member 272, a transmission gear 71, and a spring 70, and a rotary force receiving portion 474b is provided at an end of the developing rotary force receiving member 474.

As shown in fig. 53, during non-development, the coupling control member 272 rotates with the developing end cover 432 relative to the driving end cover 424 about the rotation axis X, and by the engagement of the guided portion 271i with the guide portion 424b, the coupling control member 272 is pushed to move in a direction parallel to the rotation axis X in a direction away from the driving end cover 424, and the transmission gear 71 is pushed to move in a direction away from the rotational force receiving member 474, whereby decoupling between the output arm 474a and the input arm 71n, which is the coupling, is achieved, so that the development drive is cut off.

In order to achieve decoupling of the output arm 474a and the input arm 71n, the transfer gear 71 is required to slide relative to the developing roller gear 69 in a direction parallel to the rotation axis X, so that both can only be designed as spur gears, which easily results in uneven rotation speed transferred to the developing roller, and is unfavorable for improvement of developing quality; in order to enable the sliding to slide relatively at any moment, the requirements on machining precision and installation are higher; in order to achieve the decoupling of the output arm 474a and the input arm 71n and then the coupling, the manufacturing accuracy requirements for both are high, resulting in an increase in the manufacturing cost of the entire developing cartridge.

Disclosure of Invention

An object of the present invention is to provide a developing cartridge having a developing drive switching function.

In order to achieve the above object, the present invention provides a developing cartridge including a cartridge body, a developing unit, and a driving switching unit. The developing unit includes a developing unit frame and a developing roller rotatably supported on the developing unit frame. The developing unit is supported on the cartridge body so as to be reciprocally rotatable about a rotational axis, which is both the rotational axis of the transmission gear and the rotational axis of the developing rotational force receiving member. One of the box body and the developing unit frame is provided with a limiting part, and the other is provided with a guiding part. The drive switching unit comprises a reset piece, a connecting control piece, a developing rotary force receiving piece and a transmission gear for transmitting rotary force to the developing roller; the connection control piece comprises a limited part, a guided part and a force application part, and can reciprocate along the direction parallel to the rotation axis relative to the developing unit frame; the developing rotary force receiving member is coupled to the transfer gear so as to be reciprocally movable in a direction parallel to the above-described rotation axis, that is, both are in a coupled state during the developing operation and the non-developing operation. The developing unit rotates reciprocally around the rotation axis between the connection position and the disconnection position, and the force applying part of the connection control member and the restoring member drive the developing rotation force receiving member to reciprocate along the direction parallel to the rotation axis through the cooperation of the limited part and the cooperation of the guided part and the guiding part, so that the coupling connection with the driving output member of the developing device on the main machine during the developing operation and the decoupling connection during the non-developing period are realized.

As can be seen from the above, since the developing rotational force receiving member is controlled to move in the direction parallel to the rotational axis X by the coupling control member, thereby coupling with and transmitting the rotational force required for development with the developing device driving output member on the main machine during the developing operation, and uncoupling with the developing device driving output member during the non-developing operation, to realize the switching function of the developing drive; in the whole process, the developing rotary force receiving part and the transmission gear are always in a coupling connection state, so that the transmission gear can be arranged into a bevel gear to improve the developing quality, and a coupling connection mechanism between the transmission gear and the bevel gear is convenient to arrange, thereby reducing the manufacturing cost of the developing box.

One specific scheme is that the developing rotary force receiving piece comprises a guide rod, an output arm, a rotary force receiving part positioned at one axial end of the guide rod and a force receiving part used for receiving the force applied by a force applying part on a connecting control piece. The transmission gear is provided with a first accommodating cavity with an opening at one axial end, an input arm is arranged in the first accommodating cavity, the other axial end of the transmission gear is provided with a guide hole communicated with the first accommodating cavity, and the other axial end of the guide rod penetrates through the first accommodating cavity and is in clearance fit with the guide hole. The output arm is in abutting contact with the input arm at the position where the input arm is. Simple structure, easy manufacture and assembly.

The rotary force receiving piece extends along the radial direction of the transmission gear or extends along the direction parallel to the rotation axis towards the bottom surface of the first accommodating cavity to form the output arm; the inner wall of the first accommodation chamber parallel to the rotation axis extends along the radial direction of the transfer gear or the bottom surface of the first accommodation chamber extends along the direction parallel to the rotation axis and towards the opening of the first accommodation chamber to form the input arm. The coupling and coupling structure between the developing rotary force receiving member and the transfer gear is simple and effective, and is convenient to manufacture.

Another specific embodiment is that the guide portion includes a guide surface arranged obliquely with respect to the above-mentioned rotation axis in the rotation circumferential direction of the first transmission gear and/or that the guided portion includes a guided surface arranged obliquely with respect to the above-mentioned rotation axis in the rotation circumferential direction. At least one of the guide surface and the guided surface is provided, and the relative rotation axis is arranged obliquely in the rotation circumferential direction, effectively improving conversion of the relative movement into movement in the direction parallel to the rotation axis X.

The main body of the developing rotary force receiving member is a round boss structure, and the small-diameter end surface of the round boss structure extends along a direction parallel to the rotation axis to form a rotary force receiving part. The body of the connecting control piece is a ring body structure, and the outer peripheral surface of the ring body structure protrudes along the radial direction of the ring body structure to form the guided part and the limited part. The ring body structure is sleeved outside the small-diameter part of the round boss structure and is in clearance fit with the small-diameter part. The shoulder table surface of the round boss structure forms a stress part, the end surface of the ring body structure, which is abutted against the shoulder table surface, forms a force application part, and the structure is simple and convenient to manufacture.

One more specific scheme is that the large-diameter end face of the round boss structure extends along the direction parallel to the rotation axis to form a guide rod and a ring body coaxially arranged outside the guide rod with the guide rod, and more than one first notch is arranged on the ring body along the direction parallel to the rotation axis. The transmission gear is provided with a first accommodating cavity with an opening at one axial end, the other axial end of the transmission gear is provided with a guide hole communicated with the first accommodating cavity, and one end of the guide rod, which is far away from the rotating force receiving part, penetrates through the first accommodating cavity and is in clearance fit with the guide hole. The bottom surface of the transmission gear extends along the direction parallel to the rotation axis to form a convex block matched with the first notch; the reset piece is a spring, the spring is sleeved outside the guide rod and is in clearance fit with the guide rod, one end of the spring is abutted against the large-diameter end face, and the other end of the spring is abutted against the bottom face of the first accommodating cavity.

Another more specific scheme is that the developing unit frame comprises a developing end cover, the developing end cover protrudes along the direction parallel to the rotation axis to form a cylindrical rotary supporting seat, the rotary supporting seat is provided with a second containing cavity with an opening at one axial end, the second containing cavity is used for containing the driving switching unit, the other axial end of the rotary supporting seat is provided with a through hole for exposing the rotary force receiving part, and the side wall of the second containing cavity is provided with a second notch. The box body comprises a driving end cover, the end face of the driving end cover adjacent to the developing end cover is protruded to form the limiting part, and the free end of the limited part passes through the second notch and is in abutting contact with the limiting part.

Still another specific aspect is that the restoring force of the restoring member forces the developing rotary receiving member away from the transfer gear. The developing rotary force receiving member is movable in the X-axis direction during a developing operation, so that a coupling is established between the developing device drive output member and the developing rotary force receiving member.

The reset member comprises a first magnet and a second magnet which are arranged in homopolar opposite mode, wherein the first magnet is fixed on the developing rotary force receiving member, and the second magnet is fixed on the transmission gear. The design of the reset piece structure and the arrangement of the fixed position are convenient, and the assembly process can be simplified by embedding the magnet on the developing rotary force receiving piece and the transmission gear.

The preferred embodiment is that the developing cartridge further comprises a drum unit. The drum unit includes a drum unit frame, a drum rotational force receiving member, and a photosensitive drum rotatably supported on the drum unit frame. The drum unit frame is fixedly connected with the box body.

Drawings

Fig. 1 is a perspective view of a first embodiment of the present invention;

FIG. 2 is an exploded view of the first embodiment of the present invention;

FIG. 3 is a perspective view of the first embodiment of the present invention, with the protective cover of the photosensitive drum omitted, from the view of FIG. 1;

fig. 4 is a perspective view of a developing end cap in a first embodiment of the present invention;

fig. 5 is a structural exploded view of the coupling control member and the developing rotary receiving member in the first embodiment of the present invention;

FIG. 6 is an exploded view of the return member and the transfer gear in the first embodiment of the present invention;

FIG. 7 is an exploded view of the coupling control member and developer end cap of the first embodiment of the invention;

fig. 8 is an exploded view of the drive end cap, the developing rotary receiving member, the reset member and the transfer gear in the first embodiment of the present invention;

FIG. 9 is a relative movement of the developer roller, photosensitive drum, transfer gear and coupling control member during rotation of the developer unit relative to the drive end cap about the rotational axis X in a first embodiment of the invention;

FIG. 10 is a relative positional relationship between the coupling control member and the developing end cap in the coupled state of the developing rotary force receiving member in the first embodiment of the present invention;

FIG. 11 is a relative positional relationship of the coupling control member and the developing end cap in a uncoupled state of the developing rotary force receiving member in the first embodiment of the present invention;

fig. 12 is a structural exploded view of a developing rotary force receiving member, a return member and a transfer gear in the second embodiment of the present invention;

fig. 13 is a structural exploded view of a developing rotary force receiving member, a return member and a transfer gear in a third embodiment of the present invention;

fig. 14 is an exploded view of a coupling control member and a force applying portion provided on a developing end cap in a fourth embodiment of the present invention.

The invention is further described below with reference to examples and figures thereof.

Detailed Description

The invention mainly improves the developing roller driving switching device in the developing box, and other structures of the developing box can be completely designed according to the existing products.

First embodiment

Referring to fig. 1, the developing cartridge is constituted by a driving end cap 11, a conductive end cap 12, a photosensitive drum protecting cap 13, a torque spring, a drum rotational force receiving member 3, a drum unit 4, a developing unit 5, and a drive switching unit having the developing rotational force receiving member 2. The driving end cap 11 and the conductive end cap 12 constitute a cartridge of the present embodiment, and the developing rotary receiving member 2 is rotatable about the rotation axis X.

Referring to fig. 2 and 3, the end cover 11 is provided with a support shaft hole 111 and a shaft hole 112, and an inner shaft shoulder 1120 is formed in the support shaft hole 111. The conductive end cap 12 is provided with support posts 121 and pin holes 122.

The photosensitive drum protecting cover 13 is detachably buckled on the box body through the buckling of the buckling buckle 130 and the clamping grooves formed in the upper driving end cover 11 and the conductive end cover 12, so that the exposed surface of the photosensitive drum 41 is protected in the process of storing and transporting the developing box, and the photosensitive drum protecting cover 13 needs to be taken down from the box body before being installed into a host machine.

The drum unit 4 has a drum unit frame 40, and a photosensitive drum 41 and a charging roller 42 rotatably supported on the drum unit frame 40. One end of the drum of the photosensitive drum 41 is fitted over an axial end of the drum rotational force receiving member 3 so that the rotational force received by the drum rotational force receiving member 3 from the main unit is directly transmitted to the photosensitive drum 41.

The developing unit 5 has a developing unit frame 50 and a developing roller 54 rotatably supported on the developing unit frame 50. The developing unit frame 50 has a developing end cover 51 at its longitudinal end, and a supporting shaft hole 52 matching the supporting column 121 is provided at the other end. The developing end cover 51 is provided with a rotary support seat 511, and a portion of the developing rotary force receiving member 2 is exposed by extending from the rotary support seat 511 through a through hole 512 provided at an axial end of the rotary support seat 511, and a shaft shoulder 513 is formed at a free end of the rotary support seat 511.

The driving end cover 11 and the conductive end cover 12 are fixed to both longitudinal ends of the drum unit frame 40 by pins, respectively, and the free ends of the drum rotational force receiving members 3 are exposed through the shaft holes 112; a pin (not shown) extends into the photosensitive drum 41 through the pin hole 122 to support the rotation of the photosensitive drum 41.

The supporting column 121 extends into the shaft hole 52, the rotary supporting seat 511 extends into the supporting shaft hole 111 and is in clearance fit with the shaft hole, the shaft shoulder 513 abuts against the inner shaft shoulder 1120, and the developing unit 5 is supported on the driving end cover 11 and the conductive end cover 12 in a reciprocating manner around the rotation axis X by the supporting of the supporting column 121 to the shaft hole 52 and the supporting of the rotary supporting seat 511 by the supporting shaft hole 111, i.e. can be supported on the box in a reciprocating manner.

The developing unit frame 50 is provided near the lower side of the developing end cover 51 with a pushing force receiving portion 53 for receiving the pushing force of the main unit pushing member to rotate the developing unit 5 around the rotation axis X against the torque applied to the developing unit 5 by the torque spring 14, and when the main unit pushing member is restored to the initial position, the developing unit 5 will push the developing unit 5 to rotate around the rotation axis X in the opposite direction by the elastic restoring force of the torque spring 14 provided between the developing unit 5 and the drum unit 4.

Referring to fig. 4, the rotary support base 511 is a cylindrical structure provided on the developing end cover 51, on which a second accommodation chamber 5110 open at one end in the axial direction of the cylindrical structure is provided, and on the other end in the axial direction, a through hole 512 communicating with the second accommodation chamber 5110 is provided, a second notch 514 is formed on a side wall of the second accommodation chamber 5110, three projections 515 uniformly distributed around the rotation axis X are formed on a bottom of the second accommodation chamber 5110 in a direction parallel to the rotation axis X in a projecting manner, the projections 515 constitute a guide portion of the present embodiment, and a guide surface 5150 obliquely arranged around the rotation circumference of the developing rotation force receiving member 2 as shown in fig. 1 is formed on the projections 515.

Referring to fig. 5 and 6, the drive switching unit is constituted by a coupling control member 61, a developing rotational force receiving member 2, a spring 63, and a transmission gear 64.

The body of the coupling control member 61 is a ring structure 610, and the outer peripheral surface of the ring structure 610 radially protrudes to form three guided portions 611 and a limited portion 612. The three guided portions 611 are uniformly arranged along the circumferential direction of the ring structure 610. The guided portion 611 is formed with a guided surface 6110 that cooperates with the guide surface 5150, that is, the guided surface 6110 is also arranged obliquely with respect to the rotation axis X in the rotation circumferential direction of the developing rotation force receiving member 2.

The body of the developing rotary force receiving member 2 is a circular boss structure 20, an upper axial end of the circular boss structure 20 extends along an axial direction thereof, namely, a small diameter end face of the circular boss structure 20 extends along a direction parallel to a rotation axis X to form a rotary force receiving portion 21 with a triangular cross section, a lower axial end extends along an axial direction thereof to form a guide rod 22 and a ring body 23, the ring body 23 is coaxially arranged with the guide rod 22 and is positioned outside the guide rod 22, the ring body 23 is uniformly provided with 4 first notches 231 along a rotation circumferential direction of the developing rotary force receiving member 2, the 4 first notches 231 equally divide the ring body 23 into four output arms 232, and a gap between the ring body 23 and the guide rod 22 is used for accommodating an upper end portion of a spring 63. The end of the guide rod 22 remote from the rounded boss 20 is necked to form a necked end 220.

The transmission gear 64 has a substantially cylindrical external shape, and the transmission gear 64 is provided with a first accommodation chamber 640 open at one axial end thereof, and a guide hole 644 communicating with the first accommodation chamber 640 is formed at the other axial end thereof. The radially outer wall of the transfer gear 64 is provided with circumferentially arranged helical teeth 642. The bottom surface of the first accommodation chamber 640 extends in a direction parallel to the rotation axis X, i.e., in the axial direction of the transfer gear 64 toward the opening direction of the first accommodation chamber 640 to form four projections matching the first notch 231, which constitute the input arm 641 of the present embodiment.

The necked-down end portion 220 of the guide bar 22 passes through the spring 63, the accommodation chamber 640 in order to reach the guide hole 644 in clearance fit therewith, thereby enabling the developer rotation force receiving member 2 to reciprocate relative to the transmission gear 64 in the axial direction of the guide bar 22, i.e., in the direction parallel to the rotation axis X; in the rotational direction of the developing rotational force receiving member 2, the input arm 641 is inserted into the first notch 231 and brought into abutting contact with the output arm 232, i.e., the output arm 232 is brought into abutting contact with the input arm 641 at the position of the input arm 641, thereby achieving a coupling-maintaining coupling with the transfer gear 64 during the reciprocating movement of the developing rotational force receiving member 2 relative to the transfer gear 64 in the direction parallel to the rotational axis X, to transfer the rotational force received by the rotational force receiving portion 21 to the transfer gear 64.

The upper end of the spring 63 abuts on the large diameter end face of the circular boss structure 20, and the lower end abuts on the bottom face of the first accommodation chamber 640, which constitutes the return member of the present embodiment, and its elastic restoring force constitutes the return force of the present embodiment for urging the developing rotary force receiving member 2 away from the transfer gear 64. The ring body structure 610 is sleeved outside the small-diameter part of the circular boss structure 20 and is in clearance fit with the small-diameter part, the lower end face of the ring body structure 610 abuts against the shoulder table surface 201 of the circular boss structure 20, the lower end face of the ring body structure 610 forms a force application part of the embodiment, and the shoulder table surface 201 forms a force bearing part of the embodiment.

Referring to fig. 7, after the coupling control member 61 is assembled with the rotary support base 511, i.e., the coupling control member 61 is installed in the second accommodating chamber 5110, the limited portion 612 protrudes from the second notch 514 out of the second accommodating chamber 5110, and the three guided portions 611 are respectively located in gaps between the three guiding portions 515, and the guided surface 6110 is aligned with the guiding surface 5150.

Referring to fig. 8, the developing end cover 51 provided with the coupling control member 61 is assembled with the driving end cover 11, and the developing rotary force receiving member 2, the spring 63 and the transmission gear 64 are assembled and then housed in the second housing chamber 5110, and the regulated portion 612 is brought into abutment against the regulating portion 113 during clockwise rotation of the developing end cover 51 relative to the driving end cover 11 about the rotation axis X.

Referring to fig. 9, the transfer gear 64 drives the developing roller 54 to rotate through the developing roller gear 540 with the received rotational force.

Referring to fig. 1 to 10, after the developing cartridge is loaded on the main frame of the electrophotographic image forming apparatus, the developing rotary force receiving member 2 and the drum rotary force receiving member 3 are respectively coupled with corresponding driving output members. Due to the presence of the spring 63, the developing rotary receiving member 2 is reciprocally movable in a direction parallel to the rotation axis X by the elastic restoring force thereof, thereby facilitating the coupling of the developing rotary receiving member 2 with the developing device drive output member. At this time, the main body pushing member on the main body does not exert pushing force on the pushing force receiving portion 53, the developing unit 5 and the drum unit 4 exert a torque centering on the rotation axis X against the cartridge body under the elastic restoring force of the torque spring 14, the working peripheral surface of the developing roller 54 or the spacer thereon is held against the working peripheral surface of the photosensitive drum 41 under the action of the torque to form a space required for development between the developing roller 54 and the photosensitive drum 41, the elastic restoring force of the spring 63 forces the rotation force receiving portion 21 of the developing rotation force receiving member 2 to be located at a position coupled with the developing device driving output member, and the end face of the guided portion 611 of the coupling control member 61 is held against the bottom face of the second accommodation chamber 5110, i.e., the developing unit 5 is located at a coupled position against the cartridge body. The developing rotary receiving member 2 receives a rotary force from the developing device driving output member, transmits the rotary force to the transmission gear 64 through the coupling of the output arm 232 and the input arm 641, and transmits the rotary force to the developing roller gear 540 through the gear transmission to drive the developing roller 54 to rotate normally, so as to supply the developer to the photosensitive drum 41 for development.

Referring to fig. 1 to 9 and 11, when printing is stopped, a main body pushing member on the main body applies pushing force to the pushing force receiving portion 53, causing the developing unit frame 50 to compress the torque spring 14 against the elastic restoring force of the torque spring 14, i.e., the developing unit 5 to rotate about the rotation axis X with respect to the cartridge body, thereby causing a gap larger than that required for normal development to be formed between the working peripheral surface of the developing roller 54 and the working peripheral surface of the photosensitive drum 41; since the regulated portion 612 abuts against the regulating portion 113, the coupling control member 61 is forced not to rotate about the rotation axis X together with the developing end cover 51, and the coupling control member 61 is pushed to move in a direction parallel to the rotation axis X toward the transfer gear 64 by the guide surface 5150 and the regulated surface 6110 to force the developing rotational force receiving member 2 to approach the transfer gear 64 in a direction parallel to the rotation axis X against the elastic restoring force of the spring 63, and to be uncoupled from the developing device driving output member, i.e., the developing unit 5 is located at the uncoupled position with respect to the cartridge. Since the development rotational force receiving member 2 is decoupled from the development device drive output member, the drive to the development roller 54 is cut off during non-development, and the supply of the toner to the photosensitive drum 41 is stopped.

Thereby controlling the developing rotary receiving member 2 to reciprocate in a direction parallel to the rotation axis X by the resultant force of the urging portion of the coupling control member 61 to the urging force of the urging portion and the restoring force of the restoring member.

In the present embodiment, the rotation axis X is also the rotation axis of the transmission gear 64 and the developing rotation force receiving member 2 during operation.

Second embodiment

As a description of the second embodiment of the present invention, only the differences from the first embodiment will be described below.

Referring to fig. 12, a reset member in this embodiment is formed by using a first magnetic block 7631 and a second magnetic block 7632 instead of springs, where the first magnetic block 7631 and the second magnetic block 7632 are both in a torus structure.

The necked-down end 7220 of the guide bar 722 sequentially passes through the inner holes of the first magnetic block 7631 and the second magnetic block 7632 and then is in clearance fit with the guide hole 7644.

The first magnetic block 7631 is fixed on the large-diameter end face of the circular boss structure 720 in an adhering manner, the second magnetic block 7632 is fixed on the bottom face of the first accommodating cavity 7640 in an adhering manner, and the first magnetic block 7631 and the second magnetic block 7632 are arranged in homopolar opposite manner.

The first magnetic block 7631 and the second magnetic block 7632 together constitute the reset member of the present embodiment, and the repulsive force therebetween constitutes the reset force of the present embodiment for urging the developing rotation force receiving member 72 away from the transmission gear 764.

Third embodiment

As a description of the third embodiment of the present invention, only the differences from the first embodiment will be described below.

Referring to fig. 13, the outer wall of guide rod 822 is formed with two circular rods 8232 protruding in the lateral direction to replace the ring body in the first embodiment to form the output arm of the present embodiment, the bottom surface of first accommodating chamber 8640 in transfer gear 864 is formed with ring body 8641 protruding in the direction parallel to rotation axis X, ring body 8641 is formed with two notches 8642 cooperating with circular rods 8232 in the direction parallel to rotation axis X, and ring body 8641 provided with notches 8642 is formed to replace the protrusion of the bottom of first accommodating chamber 8640 in the first embodiment to form the input arm of the present embodiment.

The upper end surface of the spring 863 abuts against the round bar 8232 instead of the large diameter end surface of the round boss structure 820.

Fourth embodiment

As a description of the fourth embodiment of the present invention, only the differences from the first embodiment will be described below.

Referring to fig. 14, the guide surface provided on the guide portion 9515 of the developing end cap 951 is omitted, that is, the portion of the guide portion 9515 that acts with the guided surface 9611 provided on the guided portion 9611 of the coupling control member 961 is a spherical surface 95150.

Fifth embodiment

As a description of the fifth embodiment of the present invention, only the differences from the fourth embodiment will be described below.

Referring to fig. 14, in contrast to the fourth embodiment, an arcuate surface is employed instead of the guided surface 96110 provided on the guided portion 9611, while the guiding surface provided on the guiding portion 9515 is not yet provided with the guiding surface in the first embodiment.

The main idea of the present invention is that the channel improves the drive switching mechanism of the developing cartridge to realize the connection with the developing device drive output member on the main machine during the developing operation by controlling the reciprocating movement of the developing rotary force receiving member along the rotation axis X, and to disconnect from the developing device drive output member during the non-developing period, thereby realizing the switching of the driving of the developing roller; there are also obvious variations of the arrangement of the output arm and the input arm, such as the input arm may be constituted by a radial extension of the transfer gear by a side wall of the first housing chamber parallel to the rotation axis X; there are also various obvious variations in the positioning of the coupling control member, the developer rotation force receiving member, and the restoring member, such as the restoring force of the restoring member forcing the developer rotation force receiving member to be close to the transfer gear, and by arranging the guide portion to extend in a direction away from the transfer gear, the coupling control member pushes the developer rotation force receiving member to be away from the transfer gear in the process of rotating the developer end cover about the rotation axis X relative to the developer end cover.

Claims

1. The developing box comprises a box body, a developing unit and a driving switching unit;

the developing unit includes a developing unit frame and a developing roller rotatably supported on the developing unit frame;

the drive switching unit comprises a transmission gear, a resetting piece, a connecting control piece and a developing rotary force receiving piece;

the developing unit is supported on the box body in a reciprocating rotation mode around a rotation axis, and the rotation axis is the rotation axis of the transmission gear and the developing rotation force receiving piece;

the method is characterized in that:

the connecting control piece comprises a limited part, a guided part and a force application part;

the box body is provided with a limiting part, and the developing unit frame is provided with a guiding part;

the coupling control member is reciprocally movable with respect to the developing unit frame in a direction parallel to the rotation axis;

the developing rotary receiving member is coupled to the transfer gear so as to be reciprocally movable in a direction parallel to the rotation axis;

the developing unit rotates reciprocally between a connection position and a disconnection position around the rotation axis along with the box body, and the guiding part comprises a guiding surface which is obliquely arranged along the rotation circumferential direction of the transmission gear relative to the rotation axis through the matching of the limited part and the limiting part and the matching of the guided part and the guiding part;

the force application part and the reset part are combined with the developing rotary force receiving part to drive the developing rotary force receiving part to reciprocate along the direction parallel to the rotation axis;

the developing rotary force receiving member comprises a guide rod, an output arm, a rotary force receiving part positioned at one axial end of the guide rod, and a force receiving part for receiving the force applied by the force applying part; the main body of the developing rotary force receiving part is a round boss structure, and the small-diameter end surface of the round boss structure extends along the direction parallel to the rotary axis to form the rotary force receiving part;

the body of the connecting control piece is of a ring body structure, and the outer peripheral surface of the ring body structure protrudes along the radial direction of the ring body structure to form the guided part and the limited part;

the ring body structure is sleeved outside the small-diameter part of the round boss structure and is in clearance fit with the small-diameter part of the round boss structure;

the shoulder table surface of the round boss structure forms the stress part, and the end surface of the ring body structure, which is abutted against the shoulder table surface, forms the force application part;

the transmission gear is provided with a first accommodating cavity with an opening at one axial end, an input arm is arranged in the first accommodating cavity, the other axial end of the transmission gear is provided with a guide hole communicated with the first accommodating cavity, and the other axial end of the guide rod passes through the first accommodating cavity and is in clearance fit with the guide hole;

the output arm is in abutting contact with the input arm at the position where the input arm is positioned;

the developing unit frame comprises a developing end cover, the developing end cover protrudes along the direction parallel to the rotation axis to form a cylindrical rotary supporting seat, the rotary supporting seat is provided with a second accommodating cavity with an opening at one axial end, the second accommodating cavity is used for accommodating the driving switching unit, the other axial end of the rotary supporting seat is provided with a through hole for exposing the rotation force receiving part, and the side wall of the second accommodating cavity is provided with a second notch;

the box body comprises a driving end cover, the end face of the driving end cover adjacent to the developing end cover protrudes to form the limiting part, and the free end of the limited part passes through the second notch and is in abutting contact with the limiting part;

the reset piece is a spring, the spring is sleeved outside the guide rod and is in clearance fit with the guide rod, one end of the spring is abutted against the large-diameter end face of the round boss structure, and the other end of the spring is abutted against the bottom face of the first accommodating cavity; or alternatively

The reset piece comprises a first magnet and a second magnet which are arranged in a homopolar opposite mode, the first magnet is fixed on the developing rotary force receiving piece, and the second magnet is fixed on the transmission gear.

2. The developing cartridge according to claim 1, wherein:

the rotational force receiving member extends in a radial direction of the transfer gear or in a direction parallel to the rotational axis toward a bottom surface of the first accommodation chamber to form the output arm;

the inner wall of the first accommodating cavity parallel to the rotation axis extends along the radial direction of the transmission gear or the bottom surface of the first accommodating cavity extends along the direction parallel to the rotation axis and towards the opening to form the input arm.

3. The developing cartridge according to claim 1, wherein:

the large-diameter end face of the circular boss structure extends along the direction parallel to the rotation axis to form a guide rod and a ring body coaxially arranged outside the guide rod with the guide rod, and the ring body is provided with more than one first notch arranged along the direction parallel to the rotation axis;

the transmission gear is provided with a first accommodating cavity with an opening at one axial end, the other axial end of the transmission gear is provided with a guide hole communicated with the first accommodating cavity, and one end of the guide rod, which is far away from the rotating force receiving part, passes through the first accommodating cavity and is in clearance fit with the guide hole;

the bottom surface of the transmission gear extends along the direction parallel to the rotation axis to form a convex block matched with the first notch.

4. The developing cartridge according to claim 1, wherein:

the restoring force of the restoring member forces the developing rotary receiving member away from the transfer gear.

5. The developing cartridge according to any one of claims 1 to 4, wherein:

the drum unit comprises a drum unit frame, a drum rotating force receiving member and a photosensitive drum rotatably supported on the drum unit frame;

the drum unit frame is fixedly connected with the box body.