CN210776192U - Processing box - Google Patents

Abstract

The utility model provides a processing box, which comprises a developing roller; a first force receiving member; a developing electrode and a switching device having a second force receiving assembly, a first electrical communicating member and a second electrical communicating member, the second force receiving assembly including a second force receiving member, the first electrical communicating member being connected with the second force receiving member and the developing roller; the second electric communication component is electrically connected with the developing electrode; the second force receiving member is movable between a first position and a second position and between the second position and a third position; the process cartridge having the structure in which the second force receiving member is located at the second position during the image forming operation and the developing roller is charged and the second force receiving member is located at the third position during the non-image forming operation in a state in which the process cartridge is loaded into the image forming apparatus, the developing roller is not charged, the process cartridge can prevent the excessive developer on the developing roller from being attached to the photosensitive drum during the non-image forming operation without adopting the separation of the developing roller from the photosensitive drum, and can ensure the printing quality and the structural stability.

Description

Processing box

[ technical field ] A method for producing a semiconductor device

The present invention relates to a process cartridge for an electrophotographic image forming apparatus, and more particularly to a process cartridge with a switch device.

[ background of the invention ]

In an image forming apparatus that forms an image by electrophotography such as a laser printer, a copying machine, a facsimile machine, etc., there is generally a process cartridge that is detachable from the image forming apparatus. The existing processing box mainly comprises: an integrated process cartridge integrating the photosensitive drum unit and the developing unit, and a divided process cartridge including only the photosensitive drum unit or the developing unit.

In the integral type process cartridge, the photosensitive drum unit and the developing unit are generally connected to each other by being rotatably movable. The photosensitive drum unit includes a photosensitive drum unit frame, a photosensitive drum rotatably supported by the photosensitive drum unit frame, a charging roller, a cleaning blade, a waste powder bin, and the like, and the developing unit includes a developing unit frame, a developing roller rotatably supported by the developing unit frame, a powder bin, a powder feeding roller, a layer thickness adjusting device, and the like. During an image forming operation, the photosensitive drum and the developing roller are in contact with each other by the force of a spring located between the developing unit and the photosensitive unit, and in the case where the image forming apparatus employs a developing method in which the developing roller is placed in contact with the photosensitive drum to develop a latent image on the photosensitive drum, the developing roller is kept pressed against the outer circumferential surface of the photosensitive drum. During non-image forming operations, the surface of the photosensitive drum is charged with excess developer due to charging of the developing roller, which causes a problem of poor printing quality.

To prevent the above problem, there is an image forming apparatus including a housing chamber, a cartridge holder, a door cover, a positioning portion provided in the housing chamber of the image forming apparatus, and a plurality of action portions and the like, wherein the action portions are distributed at a plurality of portions of the image forming apparatus for acting on and having a restraining or fixing action on a process cartridge when the process cartridge is loaded into the image forming apparatus, such as a first force application portion located above the process cartridge after the process cartridge is loaded into the image forming apparatus, a projection of a base of the image forming apparatus, a beam of the base, and the like, and a post-positioning portion provided at the process cartridge loading into the image forming apparatus for mounting the process cartridge in place in the image forming apparatus. Generally, a process cartridge is mounted on a cartridge holder of an image forming apparatus and pushed into an image forming apparatus accommodating chamber, and then has a certain moving distance in a direction perpendicular to the cartridge holder with respect to a positioning portion of the image forming apparatus, and after a door cover of the image forming apparatus is closed, the process cartridge can fall into the positioning portion of the image forming apparatus under a closing action of the door cover, and a first force application portion provided in the image forming apparatus, a convex portion of a base of the image forming apparatus, a beam of the base, and the like have an acting force on the process cartridge, and after the door cover is opened, the process cartridge is detached from the positioning portion following the cartridge holder, and the process cartridge is free from the acting force of the acting portion of the image forming. The image forming apparatus further has a separating mechanism which is provided with a second force application portion and is operable to act on the process cartridge.

A process cartridge of the related art is provided with a first force receiving member and a separating force receiving member on a developing frame, the separating force receiving member being capable of receiving a force from the first force receiving member to project from a retracted position to a projected position and of driving the developing unit frame to deflect relative to a photosensitive unit under a force of a second force application portion of a separating mechanism of an image forming apparatus, thereby separating a developing roller from a photosensitive drum; however, the separation of the photosensitive drum and the developing roller of the process cartridge occurs during a non-imaging operation, and the separation process is accompanied by compression of a spring between the developing unit and the photosensitive unit, so that the separation of the developing roller and the photosensitive drum is delayed to a certain extent by overcoming the elastic force of the spring, and further, the problem that the developing roller causes the surface of the photosensitive drum to be attached with redundant developer still exists.

[ summary of the invention ]

The utility model provides a novel integral type processing box, its accessible control processing box developing roller is electrified during the formation of image operation, developing roller is not electrified during non-formation of image operation and makes the developer can not adhere to on the sensitization drum surface during non-formation of image operation.

To achieve the above object, the present invention provides a process cartridge detachably mountable to an image forming apparatus including a first force application portion and a second force application portion; the process cartridge includes: the developing device comprises a developing unit and a photosensitive unit, wherein the photosensitive unit comprises a photosensitive unit frame and a photosensitive drum, and the developing unit comprises a developing unit frame and a developing roller; a first force receiving member, located at a first end of the process cartridge in a longitudinal direction, for receiving a force from the first force application portion; a developing electrode located at a second end of the process cartridge in a length direction; the process cartridge further includes a switching device at a first end of the process cartridge, the switching device including a second force receiving assembly including a second force receiving member and a first elastic member, a first electrical communicating member connected with the second force receiving member and the developing roller, and a second electrical communicating member; the second electric communication component is connected with the developing electrode; the second force receiving member is movable between a first position and a second position and between the second position and a third position relative to the developing unit frame; in a state where the process cartridge is loaded into the image forming apparatus, the second force receiving member is located at the second position during an image forming operation, the first electrical communication member is in electrical contact with the second electrical communication member, the developing roller is charged, the second force receiving member is located at the third position during a non-image forming operation, the first electrical communication member is not in contact with the second electrical communication member, and the developing roller is not charged.

The process cartridge having the above-described structure, after the process cartridge is loaded into the image forming apparatus, the second force receiving member is located at the second position during the image forming operation, the first electrically communicating member is in electrical contact with the second electrically communicating member, and the developing roller is charged; at the time of non-image forming operation, the second force receiving member moves from the second position to the third position, the first electrical communicating member is disconnected from the second electrical communicating member, and the developing roller is not electrified; when the image forming operation is continued, the second force receiving member returns from the third position to the second position, the first electrically communicating member is in electrical contact with the second electrically communicating member, and the developing roller is charged; therefore, the developing roller is charged during imaging operation and is not charged during non-imaging operation, and redundant developer cannot be attached to the surface of the photosensitive drum during the non-imaging operation, so that the printing quality is ensured.

Further, the second force receiving member includes a first force receiving portion, a second force receiving portion, a first mounting portion, and a supported portion, the first elastic piece having an elastic force to the second force receiving member to position the second force receiving member at the first position, the first force receiving portion for receiving a force of the first force receiving assembly to position the second force receiving member at the second position, the second force receiving portion for receiving a force of the second force applying portion to move the second force receiving member from the second position to the third position with respect to the developing unit frame.

Further, the developing unit further includes a bearing having a supporting portion on which the supported portion of the second force receiving member is fitted, the second force receiving member having a space with the bearing.

The second force receiving member is spaced from the bearing, so that a space is provided for the second force receiving member to move relative to the bearing, and the second force receiving member can deflect relative to the bearing when being acted by the force of the second force application part so as not to drive the developing unit frame to rotate.

Furthermore, the supported part is a U-shaped groove, the corresponding supporting part is a rod piece, and the U-shaped groove is sleeved on the rod piece.

The process cartridge having the above-described structure, the supporting portion thereof is provided in the "U" shaped groove so that the second force receiving member is movable in a plurality of directions relative to the lever.

Further, the "U" -shaped groove includes a first protrusion and a second protrusion, and the first protrusion has a space with the bearing in the moving direction of the second force application portion, so that the second force receiving member is displaced with respect to the bearing by the second force application portion.

The processing box with the structure has the advantages that the gap is reserved between the first lug of the U-shaped groove of the second force receiving member and the bearing in the moving direction of the second force application part, a space is provided for the second force receiving member to move relative to the bearing, when the second force receiving member is subjected to the force of the second force application part, the second force receiving member deflects relative to the bearing and cannot drive the developing unit frame to move, the first electric communication member is disconnected from the second electric communication member, and the developing roller is not electrified.

Further, the first electrical communicating member is located on the developing unit, and includes a first connecting portion provided on the first mounting portion of the second force receiving member and moving with the movement of the second force receiving member, and a second connecting portion electrically contacting the developing roller.

With the above construction, the first connection portion of the first electrical communication member moves with the movement of the second force receiving member, the first electrical communication member is in electrical contact with the second electrical communication member when the first electrical communication member is in the second position, and the first electrical communication member is not in contact with the second electrical communication member when the first electrical communication member is in the third position.

Further, first connecting portion are "U" type extension arm, and the first installation department that corresponds includes mounting hole and mounting groove, "U" type extension arm passes the mounting hole setting and has partly to be located the mounting groove.

The process cartridge having the above-described structure, the "U" -shaped extension arm can be stably mounted on the first mounting portion of the second force receiving member and moved with the movement of the second force receiving member.

Further, a second electrical communicating member is located on the developing unit and has a third connecting portion electrically connected to the developing electrode and a fourth connecting portion at least partially in contact with the "U" -shaped extension arm when the second force receiving member is in the second position.

Further, the developing unit further comprises a gear protecting cover, the gear protecting cover is provided with a second mounting portion, and the fourth connecting portion is mounted on the second mounting portion.

Furthermore, the fourth connecting portion is a hook portion, the corresponding second mounting portion is a concave portion, and the hook portion is sleeved in the concave portion.

The processing box with the structure is characterized in that the hook part is sleeved on the concave part, so that one part of the hook part faces the second force receiving component, and the hook part is contacted with the U-shaped extension arm when the second force receiving component is positioned at the second position.

Further, the first elastic member is a first compression spring.

Above-mentioned processing box uses compression spring as elastic component, and its elasticity is effectual, and simple structure, low in production cost.

Further, the first and second electrical communicating members are made of conductive filaments or sheets or wires.

Above-mentioned processing box, first electric intercommunication component and second electric intercommunication component are made by conductive wire or conducting strip or conductor wire, and its electrically conductive effect is good, and simple structure, low in production cost.

Further, when the process cartridge is loaded into the image forming apparatus, the first force receiving member receives a force from the first force applying portion and presses the second force receiving member to rotate the second force receiving member from the first position to the second position with respect to the developing unit frame, the first electrical communicating member being in electrical contact with the second electrical communicating member; when the second force receiving member receives a force from the second force application portion, the second force receiving member moves from the second position to a third position with respect to the developing unit frame, the first electrical communicating member is separated from the second electrical communicating member, and the developing roller is not electrified; when the second force receiving member is not subjected to the force from the second force application portion in the image forming operation, the second force receiving member returns from the third position to the second position, the first electrical communicating member electrically contacts the second electrical communicating member, and the developing roller is charged.

The process cartridge having the above-described structure, after the process cartridge is loaded into the image forming apparatus, the second force receiving member is located at the second position during the image forming operation, the first electrically communicating member is in electrical contact with the second electrically communicating member, and the developing roller is charged; at the time of non-image forming operation, the second force receiving member moves from the second position to the third position, the first electrical communicating member is disconnected from the second electrical communicating member, and the developing roller is not electrified; when the image forming operation is continued, the second force receiving member returns from the third position to the second position, the first electrically communicating member is in electrical contact with the second electrically communicating member, and the developing roller is charged; therefore, the developing roller is charged during imaging operation and is uncharged during non-imaging operation, redundant developer cannot be attached to the surface of the photosensitive drum during non-imaging operation, printing quality is guaranteed, and the structure is simple.

[ description of the drawings ]

FIG. 1 is a perspective view of a process cartridge according to an embodiment;

FIG. 2 is an enlarged view of a portion A of FIG. 1;

FIG. 3 is a partial exploded view of a process cartridge according to an embodiment;

FIG. 4 is an enlarged view of portion B of FIG. 3;

FIG. 5 is a schematic illustration of the structure of a first force receiving member, a second force receiving member and a bearing according to an embodiment;

FIG. 6 is a schematic structural view of a switching device, a first force receiving member, a developing roller, and a developing electrode according to an embodiment;

FIG. 7 is a positional relationship diagram of the second force receiving member, the first electrical communication member, and the second electrical communication member before the process cartridge is loaded in the image forming apparatus;

FIG. 8 is an enlarged view of portion C of FIG. 7;

FIG. 9 is a positional relationship diagram of the second force receiving member, the first electrical communication member and the second electrical communication member when the first force receiving member of the first embodiment is acted upon by the force of the first force application portion;

FIG. 10 is an enlarged view of portion D of FIG. 9;

FIG. 11 is a positional relationship diagram of the second force receiving member, the first electrical communication member and the second electrical communication member when the second force receiving member of the first embodiment is acted upon by the force of the second force application portion;

fig. 12 is an enlarged view of a portion E of fig. 11.

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

[ detailed description ] embodiments

Example one

As shown in fig. 1 to 3, the process cartridge 100 includes a photosensitive unit 1, a developing unit 2, a first end cap 3, and a second end cap 4, the first end cap 3 being mounted at a first end 5 in a longitudinal direction of the process cartridge 100, the second end cap 4 being mounted at a second end 6 in the longitudinal direction of the process cartridge 100, wherein the first end 5 is opposite to the second end 6 in the longitudinal direction of the process cartridge 100. The photosensitive unit 1 includes a photosensitive unit frame 11, a photosensitive drum 12, a charging roller (not shown), a waste toner hopper 13, and the like. The developing unit 2 includes a developing unit frame 21, a developing roller 22, a powder feed roller (not shown), a powder hopper 23, a developing electrode 24, and the like, wherein the powder hopper 23 has a first end wall 231 and a second end wall 232 in the length direction of the process cartridge 100, the first end wall 231 being adjacent to the first end cap 3, the second end wall 232 being adjacent to the second end cap 4; the developing electrode 24 is mounted on the second end wall 232 with a portion exposed outside the process cartridge 100 for electrical connection with the image forming apparatus. The photosensitive unit 1 and the developing unit 2 are rotatably movably connected together, and the photosensitive drum 12 and the developing roller 22 are in a mutual contact state by the force of a spring (not shown) located between the developing unit 2 and the photosensitive unit 1. The above-described structure of the process cartridge 100 is substantially the same as that of the prior art process cartridge, and will not be described in detail here.

As shown in fig. 2 to 6, the developing unit 2 further includes a switching device 25, a first force receiving member 26, a bearing 27, a gear cover 28, wherein the switching device 25 includes a first electrical communication member 251, a second electrical communication member 252, and a second force receiving member 253, and the second force receiving member 253 includes a second force receiving member 2531 and a first elastic member 2532. The first force receiving member 26, the second force receiving member 253, the bearing 27 and the gear cover 28 are located at the first end 5 in the longitudinal direction of the process cartridge 100 in this embodiment.

As shown in fig. 3 to 5, the bearing 27 has a plurality of guide holes 271, the corresponding first end wall 231 of the powder hopper 23 has a plurality of first protruding posts (not shown), the bearing 27 is fitted on the first end wall 231 of the powder hopper 23 through the guide holes 231 in cooperation with the first protruding posts (not shown) located on the first end wall 231 of the powder hopper 23 for supporting the developing roller 12, the powder feeding roller, and the like, the bearing 27 has a second mounting portion 272 for mounting the first force receiving member 26, a third mounting portion for mounting the first elastic member 2532, and a supporting portion, in this embodiment, the third mounting portion is a mounting protrusion (not shown). The supporting portion is used for supporting the second force receiving member 2531 so that the second force receiving member 2531 can rotate relative to the developing unit frame 21, and the supporting portion of the bearing 27 is a lever 273 in this embodiment. A gear cover 28 is fitted on the side of the bearing 27 close to the first end cover 3 of the process cartridge for covering the developing unit drive gear and the like, and a cutout portion 281 is provided on the gear cover 28 so that the second force receiving member 2531 of the process cartridge 100 can be located in the cutout portion 281 before being loaded into the image forming apparatus.

As shown in fig. 5, 6 and 9, the first force receiving member 26 includes a first force receiving member 261 and a second elastic member, which in this embodiment is a second compression spring 262. The first force receiving member 261 includes a third force receiving portion 2611, an abutting portion 2612, wherein the third force receiving portion 2611 is used for receiving the force from the first force application portion 201 of the image forming apparatus, the abutting portion 2612 abuts on the second force receiving member 2531, the second compression spring 262 is mounted on the first force receiving member 261 and the first force receiving member 261 has an elastic force.

As shown in fig. 4 to 10, in the present embodiment, the switch device 25 comprises a first electrical communication member 251, a second electrical communication member 252 and a second force receiving assembly 253, the second force receiving assembly 253 comprising a second force receiving member 2531 and a first resilient member. In the present embodiment, the first elastic member is a first compression spring 2532, one end of the first compression spring 2532 is mounted on a mounting projection (not shown) of the bearing 27, and the other end is pressed against the second force receiving member 2531, and has an elastic force to the second force receiving member 2531, so that the second force receiving member 2531 is positioned in the notch portion 281 of the gear cover 28 with respect to the developing unit frame 21 before the process cartridge 100 is loaded into the image forming apparatus. In the moving direction a of the second force application portion 202 of the image forming apparatus, the second force receiving member 2531 has a front side surface 25311 and a rear side surface 25312, a front side surface 25311 located in front of the moving direction a of the second force application portion, a rear side surface 25312 located behind the moving direction a of the second force application portion 202, and a gap between the front side surface 25311 and the rear side surface 25312 of the second force receiving member 2531 and the bearing 27, the gap providing a moving space for the second force receiving member 2531 to deflect relative to the bearing 27. The second force receiving member 2531 includes a first force receiving portion 25313, a second force receiving portion 25314, a first mounting portion 25315 and a supported portion, wherein the first force receiving portion 25313 is a cam structure, and the second force receiving member 2531 can rotate relative to the developing unit frame 21 under the pressing of the pressing portion 2612 of the first force receiving member 261, so that the second force receiving member 2531 protrudes from the developing unit frame 21 to the outside of the process cartridge 100; the second force receiving portion 25314 is located above and on the opposite side of the first force receiving portion 25313 in the state where the process cartridge 100 is mounted to the image forming apparatus, the first force receiving portion 25313 is located on the front side of the second force receiving member 2531 and the second force receiving portion 25314 is located on the rear side of the second force receiving member 2531 in the moving direction of the second force application portion 202; the second force receiving portion 25314 is for receiving a force from the imaging apparatus second force application portion 202, so that the second force receiving member 2531 is deflected with respect to the bearing 27. In this embodiment, the supported portion is a "U" shaped groove 25316, and the "U" shaped groove 25316 may fit over the lever 273 so that the second force receiving member 2531 may rotate about the lever 273 relative to the developing unit frame 21; the "U" -shaped groove 25316 has a first protrusion 253161 and a second protrusion 253162, wherein the rear side of the first protrusion 253161 is spaced apart from the bearing 27 in the moving direction a of the second force application portion 202, and can be deflected with respect to the bearing 27 without the bearing 27 being deflected when the second force receiving portion 25314 of the second force receiving member 2531 receives the force of the second force application portion 202.

As shown in fig. 2 to 6, 9, 10, the first and second electrical communication members may be made of a conductive wire or sheet, in this embodiment the first electrical communication member 251 is made of a conductive wire and has a first connection portion and a second connection portion 2512, the first connection portion is a "U" -shaped extension arm 2511, the first mounting portion 25315 of the corresponding first force receiving member 2531 includes a mounting hole 253151 and a mounting groove 253152, the "U" -shaped extension arm 2511 is mounted through the mounting hole 253151 of the second force receiving member 2531 and has a portion located within the mounting groove 253152 such that the "U" -shaped extension arm 2511 may rotate with the rotation of the second force receiving member 2531, the "U" -shaped extension arm 2511 has a portion exposed on the rear side surface 25312 of the second separating force receiving member 2531; the second electrical communicating member 252 is made of a conductive wire and is located on the developing unit frame 21, having a third connecting portion 2521 and a fourth connecting portion; a second boss 2321 on the second end wall 232 of the powder hopper 23, a third boss 2331 on the powder hopper sidewall 233 between the first end wall 231 and the second end wall 232, and a portion of the second electrical communication member 252 supported by the third boss 2331; the third connecting portion 2521 is wound around the second boss 2321 of the second end wall and is in electrical contact with the developing electrode 24, the fourth connecting portion is a hook portion 2522, the hook portion 2522 is hung in the recess 282 of the gear cover 28, and the hook portion 2522 has a portion facing the rear side 25312 of the second force receiving member 2531, the hook portion 2522 being in electrical contact with the "U" -shaped extension arm 2511 when the second force receiving member 2531 is in the second position.

Referring next to fig. 4 to 12, the charging process of the developing roller 21 of the process cartridge 100 during the image forming operation and during the non-image forming operation of the process cartridge 100 will be described in detail.

Fig. 7 is a positional relationship diagram of the second force receiving member 2531, the first electrical communicating member 251, and the second electrical communicating member 252 before the process cartridge is loaded into the image forming apparatus, and as shown in fig. 7 and 8, the second force receiving member 2531 is located in the notch portion 281 of the gear cover 28, the "U" shaped extension arm of the first electrical communicating member may be in contact with or not in contact with the hook portion of the second electrical communicating member at this time, in this embodiment, the "U" shaped extension arm 2511 of the first electrical communicating member 251 is not in contact with the hook portion 2522 of the second electrical communicating member 252, and in this embodiment, the position of the second force receiving member 2531 with respect to the developing frame 21 at this time is the first position. Fig. 9 is a positional relationship diagram of the second force receiving member 2531, the first electrical communication member 251 and the second electrical communication member 252 when the first force receiving member 2531 is subjected to the acting force of the first force application portion 201, and as shown in fig. 9 and 10, the second force receiving portion 25314 protrudes beyond the outer surface of the developing frame 21, the "U" -shaped extension arm 2511 of the first electrical communication member 251 is in electrical contact with the hook portion 2522 of the second electrical communication member 252, and the position of the second force receiving member 2531 relative to the developing frame 21 at this time is the second position in the present embodiment. Fig. 11 is a positional relationship diagram of the second force receiving member 2531, the first electrical communication member 251 and the second electrical communication member 252 when the second force receiving member 2531 is acted by the force of the second force application portion 202, and as shown in fig. 11 and 12, the second force receiving member 2531 deflects relative to the bearing 27, the "U" -shaped extension arm 2511 of the first electrical communication member 251 is not in contact with the hook portion 2522 of the second electrical communication member 252, and the position of the second force receiving member 2531 relative to the developing frame 21 at this time is a third position in this embodiment.

As shown in fig. 4 to 12, the second force receiving member 2531 is located at the first position by the elastic force of the first compression spring 2532 before the process cartridge 100 is loaded into the image forming apparatus. After the process cartridge 100 is loaded into the image forming apparatus, the first force receiving member 261 is subjected to the force of the first force application portion 201, the pressing portion 2612 of the first force receiving member 261 presses against the first force receiving portion 25313 of the second force receiving member 2531, so that the second force receiving member 2531 rotates from the first position to the second position, and the "U" -shaped extension arm 2511 of the first electrical communication member 251 is in electrical contact with the hook portion 2522 of the second electrical communication member 252; after the process cartridge 100 is loaded into the image forming apparatus and in the image forming operation, the second force receiving member 2531 is located at the second position, the "U" -shaped extension arm 2511 of the first electrifying member 251 is in electrical contact state with the hook portion 2522 of the second electrifying member 252, and the developing roller 22 is electrified; after the process cartridge is loaded into the image forming apparatus and in the non-image forming operation, the second force receiving member 2531 is subjected to the force of the second force application portion 202, the second force receiving member 2531 is deflected relative to the bearing 27, the bearing 27 is not deflected, the second force receiving member 2531 is in the third position relative to the bearing 27, the "U" -shaped extension arm 2511 is not in contact with the hook portion 2522 of the second electrical communication member 252, and the developing roller 22 is not electrified; the second compression spring 262 is compressed against the elastic force of the second compression spring 262 of the first force receiving member 261 during the deflection of the second force receiving member 2531, and then when the process cartridge 100 is in the non-operating state, the second force application portion 202 does not apply a force to the second force receiving portion 25314 of the second force receiving member 2531, and the developing roller 22 is charged by the elastic restoring force of the second compression spring 262 as the pressing portion 2612 of the first force receiving member 261 presses against the first force receiving portion 25313 of the second force receiving member 2531 and the second force receiving member 2531 returns from the third position to the second position by the elastic restoring force of the second compression spring 262, and the "U" -shaped extension arm 2511 comes into electrical contact with the hook portion 2522 of the second electrical communication member 252. By this, the process cartridge 100 of the present embodiment, after being loaded into the image forming apparatus, can control the charging of the developing roller 22 by the switching device 25 during the image forming operation and the power-off of the developing roller 22 by the switching device 25 during the non-image forming operation, and can prevent the excessive developer on the developing roller 22 from adhering to the photosensitive drum without forming an image without employing the separation of the developing roller 22 from the photosensitive drum 21, and can ensure the printing quality.

The above embodiments are merely preferred embodiments of the present invention, and the scope of the present invention is not limited thereto. There are also numerous variations in the shape, construction and principles of the present invention, e.g., the first resilient member may be integral with the second force receiving member or may be separately provided, the first mounting portion of the first force receiving member may be a protrusion, and the like. Therefore, any changes and modifications made without departing from the spirit and scope of the present invention should be covered by the present invention.

Claims (13)

1. A process cartridge detachably mountable to an image forming apparatus including a first force application portion and a second force application portion; the process cartridge includes:

the developing device comprises a developing unit and a photosensitive unit, wherein the photosensitive unit comprises a photosensitive unit frame and a photosensitive drum, and the developing unit comprises a developing unit frame and a developing roller;

a first force receiving member, located at a first end of the process cartridge in a longitudinal direction, for receiving a force from the first force application portion;

a developing electrode located at a second end of the process cartridge in a length direction; the method is characterized in that:

the process cartridge further includes a switch device at the first end of the process cartridge, the switch device including a second force receiving assembly including a second force receiving member and a first elastic member, a first electrical communicating member connected with the second force receiving member and the developing roller, and a second electrical communicating member; the second electrical communication member is connected with the developing electrode;

the second force receiving member is movable between a first position and a second position and between a second position and a third position relative to the developing unit frame;

in a state in which the process cartridge is loaded into the image forming apparatus, the second force receiving member is located at the second position during an image forming operation, the first electrical communication member is in electrical contact with the second electrical communication member, the developing roller is charged, the second force receiving member is located at the third position during a non-image forming operation, the first electrical communication member is not in contact with the second electrical communication member, and the developing roller is not charged.

2. A process cartridge according to claim 1, wherein:

the second force receiving member includes a first force receiving portion, a second force receiving portion, a first mounting portion, and a supported portion, the first elastic piece having an elastic force on the second force receiving member to position the second force receiving member at the first position, the first force receiving portion being for receiving a force of the first force receiving component to position the second force receiving member at the second position, the second force receiving portion being for receiving a force of the second force application portion to move the second force receiving member from the second position to the third position with respect to the developing unit frame.

3. A process cartridge according to claim 2, wherein:

the developing unit further includes a bearing having a supporting portion on which the supported portion of the second force receiving member is fitted, the second force receiving member and the bearing having a space therebetween.

4. A process cartridge according to claim 3, wherein:

the supported part is a U-shaped groove, the corresponding supporting part is a rod piece, and the U-shaped groove is sleeved on the rod piece.

5. A process cartridge according to claim 4, wherein:

the U-shaped groove comprises a first lug and a second lug, and an interval is formed between the first lug and the bearing in the moving direction of the second force application part, so that the second force receiving component is deviated relative to the bearing under the action of the second force application part.

6. A process cartridge according to any one of claims 2 to 5, wherein:

the first electrical communicating member is located on the developing unit, and includes a first connecting portion provided on the first mounting portion of the second force receiving member and moving with movement of the second force receiving member, and a second connecting portion electrically contacted with the developing roller.

7. A process cartridge according to claim 6, wherein:

first connecting portion are "U" type extension arm, correspond first installation department includes mounting hole and mounting groove, "U" type extension arm passes the mounting hole sets up and has partly to be located the mounting groove.

8. A process cartridge according to claim 7, wherein:

the second electrical communicating member is located on the developer unit and has a third connecting portion electrically connected to the developer electrode and a fourth connecting portion at least a portion of which contacts the "U" shaped extension arm when the second force receiving member is in the second position.

9. A process cartridge according to claim 8, wherein:

the developing unit further comprises a gear protecting cover, the gear protecting cover is provided with a second installation part, and the fourth connecting part is installed on the second installation part.

10. A process cartridge according to claim 9, wherein:

the fourth connecting part is a hook part, the corresponding second mounting part is a concave part, and the hook part is sleeved in the concave part.

11. A process cartridge according to any one of claims 7 to 10, wherein:

the first elastic piece is a first compression spring.

12. A process cartridge according to any one of claims 7 to 10, wherein:

the first and second electrical communicating members are made of conductive filaments or sheets or wires.

13. A process cartridge according to claim 12, wherein:

when the process cartridge is loaded into the image forming apparatus, the first force receiving member receives a force from the first force applying portion and presses against the second force receiving member to rotate the second force receiving member relative to the developing unit frame from the first position to the second position, the first electrical communicating member being in electrical contact with the second electrical communicating member; when the second force receiving member receives a force from the second force application portion, the second force receiving member moves from the second position to the third position with respect to the developing unit frame, the first electrical communication member is disengaged from the second electrical communication member, and the developing roller is not charged; in an image forming operation, when the second force receiving member is not subjected to a force from the second force application portion, the second force receiving member returns from the third position to the second position, the first electrical communicating member is in electrical contact with the second electrical communicating member, and the developing roller is charged.

Images