CN208172510U - Image forming apparatus - Google Patents

Abstract

The utility model provides an image forming device, comprising: a drum box with a photosensitive drum; a developing box assembled in the drum box, having a developing roller and a reset gear, and the reset gear has a protrusion; a casing, the developing box is assembled in the casing , the casing has an opening into which the developer cartridge in the state assembled to the drum cartridge can be inserted; the cover can move between a closed position and an open position; the LED unit for exposing the photosensitive drum can move together with the cover, in an exposure position when the cover is in the closed position, and a disengaged position when the cover is in the open position; a lever capable of contacting the protrusion and movable between a first position and a second position; and an attached cover capable of being assembled to the drum cartridge During the assembly of the developing cartridge of the attached cover, during the assembly of the developing cartridge with the attached cover to the housing, the attached cover contacts the lever to move the lever from the first position to the second position. In the state where the lever is located at the second position , a part of the rod guides the LED unit from the separation position to the exposure position.

Description

image forming device

technical field

The utility model relates to an image forming device.

Background technique

Conventionally, electrophotographic image forming apparatuses such as LED printers are known. A detachable cartridge is used in such an image forming apparatus. For example, Patent Document 1 describes a conventional image forming apparatus having a detachable cartridge. The image forming apparatus of Patent Document 1 includes: a casing having a slot; a cover movable to an open position opening an opening of the slot and a closed position closing the opening; and an LED unit movable together with the cover. The cartridge fits to the slot via the opening of the housing. And when the cover is moved from the open position to the closed position, the LED unit is moved from the separation position to the exposure position.

prior art literature

patent documents

Patent Document 1: Japanese Unexamined Patent Publication No. 2013-54058

Utility model content

Problems to be solved by utility models

Usually, an image forming apparatus is shipped with a cartridge attached to a casing when shipped from a factory. During shipping, the housing fitted with the cartridge may be subjected to vibrations. Even if vibration during transportation is assumed, the LED unit needs to be positioned stably at the exposure position.

An object of the present invention is to provide an image forming apparatus capable of stably positioning an LED unit at an exposure position when a casing equipped with a cassette is transported.

Solution to the problem

In order to solve the above-mentioned problems, the first solution of the present application includes: a drum cartridge having a photosensitive drum; The first shaft rotates, the reset gear can rotate around the second shaft extending in the first direction, and has a protrusion; the housing is assembled in the developing cartridge in the state of the drum cartridge The housing is provided with an opening into which the developer cartridge in a state assembled to the drum cartridge can be inserted; and a cover is movable between a closed position for closing the opening and an open position for opening the opening. an LED unit for exposing the photosensitive drum, movable together with the cover, in an exposure position capable of exposing the photosensitive drum with the cover in the closed position , when the cover is in the open position, the LED unit is located at a separate position farther from the photosensitive drum than the exposure position; the lever is capable of contacting the protrusion and can be positioned between the first position and the second position and an attached cover capable of being assembled to the developing cartridge mounted on the drum cartridge, covering at least a part of the developing cartridge mounted on the drum cartridge, in the state where the attached cover is mounted During assembly of the developing cartridge to the casing, the accessory cover contacts the lever to move the lever from the first position to the second position, and when the lever is in the second In the state of the position, a part of the rod guides the LED unit from the separation position to the exposure position.

A second aspect of the present application is based on the image forming apparatus of the first aspect, wherein the LED unit moves from the separated position to the closed position as the cover moves from the open position to the closed position. During movement of the exposure position, a part of the rod guides the LED unit from the separation position to the exposure position.

A third aspect of the present application is based on the image forming apparatus according to the first aspect or the second aspect, wherein the accessory cover has a separation part, and the accessory cover is attached to the developing cartridge attached to the drum cartridge. In a state where the separating part separates the photosensitive drum from the developing roller.

A fourth aspect of the present application is based on the image forming apparatus according to the first to third aspects, further comprising an optical sensor that detects the lever located at the second position.

A fifth aspect of the present application is based on the image forming apparatuses of the first to fourth aspects, wherein the accessory cover has a direction along an insertion direction of the developing cartridge mounted on the drum cartridge into the casing. During the assembly of the auxiliary cover to the housing in the state of being assembled to the developing cartridge assembled on the drum cartridge, the contact surface is in contact with the lever to move the lever from the The first position moves toward the second position.

A sixth aspect of the present application is based on the image forming apparatuses of the first to fifth aspects, wherein the developing cartridge has: a toner storage portion capable of accommodating toner; and a development coupling capable of The third shaft extending in the first direction rotates and is located at one end of the toner storage portion in the first direction, and the reset gear is located in the toner container in the first direction. the other end of the agent containing part.

A seventh aspect of the present application is based on the image forming apparatus of the sixth aspect, wherein the developing cartridge has: a storage medium having an electrical contact surface; and a holder for accommodating the toner in the first direction One side of the part holds the electrical contact surface, the bracket has a first outer surface, a second outer surface and an elastic member, the first outer surface is located on one side of a third direction intersecting the electrical contact surface, The electrical contact surface is held, the second outer surface is located on the other side of the third direction, and is located at a position separated from the first outer surface in the third direction, and the elastic member is located in the Between the first outer surface and the second outer surface, it can expand and contract in the third direction, and is connected with the first outer surface and the second outer surface, and the elastic member expands and contracts The distance between the first outer surface and the second outer surface in the third direction changes, and the accessory cover has a bracket cover, and the bracket cover is assembled on the bracket to cover at least a part of the bracket. When the bracket cover is assembled on the bracket, the bracket cover presses the first outer surface toward the second outer surface, and presses the second outer surface toward the first outer surface. In the state where the bracket cover is separated from the bracket, the length of the elastic member in the third direction becomes a first length, and in the state where the bracket cover is mounted on the bracket, the length of the elastic member in the third direction is the first length. The length of the elastic member is a second length shorter than the first length.

An eighth aspect of the present application is based on the image forming apparatus of the seventh aspect, wherein, in a state where the bracket cover is mounted on the bracket, the electrical contact surface faces the electrical contact surface in the third direction. The inner surface of the bracket cover is separated from the contact surface.

A ninth aspect of the present application is based on the image forming apparatuses of the first to eighth aspects, wherein the drum cartridge has a drum coupling positioned on the photosensitive drum in the first direction. The attached cover covers the drum coupling of the drum cartridge when it is attached to the developing cartridge in the assembled state of the drum cartridge.

A tenth aspect of the present application is based on the image forming apparatuses of the sixth to eighth aspects, wherein the accessory cover covers the Described development coupling.

An eleventh aspect of the present application is based on the image forming apparatuses of the first to tenth aspects, wherein the accessory cover covers the At least a portion of the gear is reset.

A twelfth aspect of the present application is based on the image forming apparatuses of the seventh to eleventh aspects, wherein an electrical contact capable of contacting the electrical contact surface is provided, and when the holder cover is not attached to the holder, When the developing cartridge in the state is assembled to the casing, the electrical contacts are in contact with the electrical contact surface, and the developing cartridge in the state in which the bracket cover is assembled to the bracket is assembled to the housing. In the case of the image forming apparatus described above, the electrical contact is located at a position separated from the electrical contact surface in the third direction.

Utility Model Effect

According to the first aspect to the twelfth aspect of the present application, when the developing cartridge is attached to the housing in a state where the attached cover is attached, the lever is pressed and moved from the first position to the second position. And, the LED unit is guided to the exposure position by a part of the rod moved to the second position. Thereby, the LED unit can be stably positioned at the exposure position.

In particular, according to the sixth aspect of the present application, the friction between the electrical contact surface and the inner surface of the bracket cover can be avoided.

Description of drawings

FIG. 1 is a perspective view of a process cartridge mountable in an image forming apparatus.

Fig. 2 is an exploded perspective view of the developing cartridge with the IC chip assembly disassembled.

Fig. 3 is an exploded perspective view of the developing cartridge with the second gear part disassembled.

4 is a longitudinal sectional view of the image forming apparatus.

Fig. 5 is a diagram showing a state in which the process cartridge is mounted in the socket.

Fig. 6 is a perspective view of a process cartridge equipped with an attached cover.

Fig. 7 is a perspective view with a cover.

Fig. 8 is a view showing a state where the process cartridge with the attached cover is attached to the slot.

Fig. 9 is a view showing a state in the middle of insertion of the process cartridge with the cover attached thereto.

Fig. 10 is a diagram showing a state in the middle of insertion of the process cartridge with the cover attached thereto.

Fig. 11 is a diagram for explaining a guide portion and a rod.

Fig. 12 is a diagram showing a state where the process cartridge with the attached cover is attached to the slot.

Fig. 13 is a view showing a state where the process cartridge with the attached cover is attached to the slot.

Detailed ways

Hereinafter, embodiment of this invention is demonstrated with reference to drawings.

It should be noted that, hereinafter, the longitudinal direction of the developing roller of the developing cartridge is referred to as "the first direction". Also, the insertion direction of the process cartridge with respect to the casing of the image forming apparatus is referred to as "second direction". Also, the direction intersecting the electrical contact surface is referred to as a "third direction". In the following embodiments, the first direction intersects (preferably perpendicular to) the second direction, the second direction intersects the third direction, and the third direction intersects (preferably orthogonal) to the first direction.

<1. About the process cartridge>

FIG. 1 is a perspective view of a process cartridge 1 that can be assembled in an image forming apparatus.

The process cartridge 1 has a drum cartridge 2 and a developing cartridge 3 . The developer cartridge 3 is detachable from the drum cartridge 2 . A user of the image forming apparatus can replace only one of the drum cartridge 2 and the developing cartridge 3 with a new one. Therefore, the life of the drum cartridge 2 and the life of the developing cartridge 3 can be effectively consumed, respectively.

It should be noted that, below, the structure of each part of the process cartridge 1 in the state of being mounted in the image forming apparatus will be described using the above-mentioned first direction, second direction, and third direction.

<1.1. About drum cartridges>

The drum cartridge 2 transfers the toner supplied from the developing cartridge 3 to the printing paper via the photosensitive drum 22 . The drum cartridge 2 has a drum frame 21 , a photosensitive drum 22 and a gear unit 23 .

The drum frame 21 is a frame capable of fitting the developing cartridge 3 . The drum frame 21 has a frame main body 211 and a frame cover 212 . The frame cover 212 is fixed relative to the frame main body 211 . The photosensitive drum 22 is located between the frame main body 211 and the frame cover 212 . However, the drum frame 21 may be composed of a single member, or may be composed of three or more members.

The drum frame 21 has one end portion 213 in the second direction and the other end portion 214 away from the one end portion 213 in the second direction. One end portion 213 is closer to the photosensitive drum 22 than the other end portion 214 . The drum frame 21 has a concave portion 210 between one end portion 213 and the other end portion 214 into which the developing cartridge 3 is inserted.

The photosensitive drum 22 is a drum rotatable about a rotation shaft extending in the first direction. The photosensitive drum 22 is located at one end portion 213 of the drum frame 21 in the second direction. The photosensitive drum 22 has a drum main body and a drum shaft. The drum main body is a cylindrical member extending in the first direction. The outer peripheral surface of the drum main body is covered with a photosensitive material. The drum shaft is a cylindrical member extending in the first direction along the rotation axis of the photosensitive drum 22 . The drum shaft is located at least one end of the drum body in the first direction. The drum main body is relatively non-rotatably fixed with respect to the drum shaft.

It should be noted that the drum shaft may pass through the drum main body in the first direction. For example, the drum shaft may be inserted into a through hole provided in the center of the drum main body. Furthermore, the pair of drum shafts may respectively extend in the first direction from both ends of the drum main body in the first direction.

As a material of the drum shaft, for example, metal as a conductor is used. The drum shaft is connected to a ground terminal of the image forming apparatus. Thus, the drum shaft is maintained at the reference voltage.

The gear portion 23 is located at one end of the drum cartridge 2 in the first direction. The gear unit 23 has a plurality of gears and a drum coupling 231 . A plurality of gears are accommodated in a space formed between the frame main body 211 and the frame cover 212 . The drum coupling 231 is exposed from the drum frame 21 . When the process cartridge 1 is assembled to the image forming apparatus, the drive shaft of the image forming apparatus is connected to the drum coupling 231 . Furthermore, the rotation of the drive shaft is transmitted to a plurality of gears via the drum coupling 231 .

It should be noted that the plurality of gears included in the gear unit 23 may be gears that transmit rotational force through meshing of teeth, or may be gears that transmit rotational force through friction.

<1.2. About the developing cartridge>

FIG. 2 is an exploded perspective view of the developing cartridge 3 with the IC chip assembly 35 disassembled. FIG. 3 is an exploded perspective view of the developer cartridge 3 with the second gear portion 34 disassembled.

The developer cartridge 3 is fitted to the recessed portion 210 of the drum frame 21 . The developing cartridge 3 supplies toner to the photosensitive drum 22 of the drum cartridge 2 . The developing cartridge 3 has a casing 30 , an agitator 31 , a developing roller 32 , a first gear portion 33 , a second gear portion 34 , and an IC chip unit 35 .

The case 30 is a toner storage portion capable of storing toner, and extends along the first direction. The housing 30 has a first side panel 301 and a second side panel 302 . The first side plate 301 is located at one end of the housing 30 in the first direction. The second side plate 302 is located at the other end of the housing 30 in the first direction. The first side plate 301 is separated from the second side plate 302 in a first direction. The first gear part 33 and the IC chip assembly 35 are located on the outer surface of the first side plate 301 . Inside the casing 30 is provided a toner chamber 303 that stores toner. Furthermore, the case 30 has an opening 304 . The opening portion 304 is located at one end of the housing 30 in the second direction. The toner chamber 303 communicates with the outside through the opening 304 .

The stirrer 31 has a stirring shaft 311 and a stirring blade 312 . The stirring shaft 311 extends along the first direction. The stirring blade 312 expands radially outward from the stirring shaft 311 . At least a part of the stirring shaft 311 and the stirring blade 312 are disposed inside the toner chamber 303 . A stirring gear is attached to one end portion of the stirring shaft 311 in the first direction. The stirring shaft 311 and the stirring blade 312 rotate together with the stirring gear. When the stirring blade 312 rotates, the toner in the toner chamber 303 is stirred.

The developing roller 32 is a roller rotatable about a rotation axis (first axis) extending in a first direction. The developing roller 32 is located at the opening 304 of the housing 30 . That is, the developing roller 32 is located at one end of the housing 30 in the second direction. When the developing cartridge 3 is mounted on the drum cartridge 2 , the outer peripheral surface of the developing roller 32 is in contact with the outer peripheral surface of the photosensitive drum 22 .

The second direction is also the insertion direction of the developing cartridge 3 mounted on the drum cartridge 2 with respect to the slot 91 of the image forming apparatus 100 .

The developing roller 32 has a developing roller main body 321 and a developing roller shaft 322 . The developing roller main body 321 is a cylindrical member extending in the first direction. The material of the developing roller main body 321 is elastic rubber, for example. The developing roller shaft 322 is a cylindrical member penetrating through the developing roller main body 321 in the first direction. Metal or conductive resin is used as a material for the developing roller shaft 322 . The developing roller main body 321 is relatively non-rotatably fixed with respect to the developing roller shaft 322 .

One end portion of the developing roller shaft 322 in the first direction is fixed to a developing roller gear 332 that is a part of the first gear portion 33 . Therefore, the developing roller shaft 322 and the developing roller main body 321 are rotated by the driving of the first gear portion 33 . It should be noted that the developing roller shaft 322 may not pass through the developing roller main body 321 in the first direction. For example, a pair of developing roller shafts 322 may respectively extend from both ends of the developing roller main body 321 in the first direction along the first direction.

In addition, the developing cartridge 3 has a supply roller which is not shown in the figure. The supply roller is located between the developing roller 32 and the toner chamber 303 . Toner is supplied from the toner chamber 303 to the outer peripheral surface of the developing roller 32 via a supply roller. At this time, the toner is charged by friction between the supply roller and the developing roller 32 . On the other hand, a bias voltage is applied to the developing roller shaft of the developing roller 32 . Therefore, the toner is attracted to the outer peripheral surface of the developing roller 32 by the electrostatic force between the developing roller shaft and the toner.

In addition, the developer cartridge 3 has a layer thickness regulating blade (not shown). The layer thickness regulating blade shapes the toner supplied to the outer peripheral surface of the developing roller 32 to a constant thickness. Then, the toner on the outer peripheral surface of the developing roller 32 is supplied to the photosensitive drum 22 . At this time, the toner moves from the developing roller main body to the photosensitive drum 22 according to the electrostatic latent image formed on the outer peripheral surface of the photosensitive drum 22 . Thereby, visualization of the electrostatic latent image is realized at the outer peripheral surface of the photosensitive drum 22 .

The first gear part 33 is located on the outer surface of the first side plate 301 of the housing 30 . The first gear unit 33 has a plurality of gears including the aforementioned stirring gear and developing roller gear 332 , and a developing coupling 331 . At least a part of the plurality of gears is located between the first side plate 301 and an inner cover 371 described later. The development coupling 331 is rotatable about a rotation shaft (third shaft) extending in the first direction. The development coupling 331 is exposed from the inner cover 371 . When the process cartridge 1 is assembled in the image forming apparatus, the drive shaft of the image forming apparatus is connected to the developing coupling 331 . Further, the rotation of the drive shaft is transmitted to a plurality of gears including the developing roller gear 332 via the developing coupling 331 .

The developing roller gear 332 is rotatable about a rotation shaft (first shaft) extending in the first direction. The developing roller gear 332 is a gear for rotating the developing roller 32 . A plurality of gear teeth are provided at equal intervals over the entire circumference of the outer peripheral portion of the developing roller gear 332 . A part of the plurality of gear teeth of the developing coupling 331 meshes with a part of the plurality of gear teeth of the developing roller gear 332 . Also, the developing roller gear 332 is fixed to the end portion of the developing roller shaft 322 in the first direction in a relatively non-rotatable manner. Therefore, when the developing coupling 331 rotates, the developing roller gear 332 rotates, and the developing roller 32 also rotates together with the developing roller gear 332 .

The idler gear is a gear for transmitting the rotation of a plurality of gears including the development coupling 331 to the agitation gear. The stirring gear is a gear for rotating the stirrer 31 . The stirring gear is rotatable about a rotation axis extending in a first direction. A plurality of gear teeth are provided at equal intervals over the entire circumference of the outer peripheral portion of the stirring gear. The stirring gear is fixed to one end of the stirring shaft 311 in the first direction so as to be relatively non-rotatable. Therefore, when power is transmitted from the developing coupling 331 to the agitation gear via the idler gear, the agitation gear rotates, and the agitator 31 also rotates together with the agitation gear.

The inner cover 371 is fixed to the outer surface of one end of the housing 30 in the first direction, for example, by screw fastening. The inner cover 371 accommodates the development coupling 331 , the development roller gear 332 , an idler gear, a stirring gear, and the like. The inner cover 371 has a cylindrical collar 372 extending in the first direction. The developing coupling 331 is fitted into the collar 372 . Furthermore, the developing cartridge 3 has a cover 373 . The outer cover 373 is fixed to the inner cover 371 . The outer cover 373 is located on a side opposite to the outer case 30 with respect to the inner cover 371 in the first direction.

It should be noted that the plurality of gears included in the first gear portion 33 may be gears that transmit rotational force through meshing of teeth, or may be gears that transmit rotational force through friction.

The second gear part 34 is located on the outer surface of the second side plate 302 of the housing 30 . As shown in FIG. 3 , the second gear unit 34 has a reset gear 341 . The reset gear 341 is located at the other end of the housing 30 in the first direction. Also, the reset gear 341 is rotatable around a rotation shaft (second shaft) extending in the first direction in accordance with the driving force received by the development coupling 331 .

A protrusion 343 is provided on the outer peripheral surface of the reset gear 341 . The protrusion 343 rotates with the rotation of the reset gear 341, and its position in the circumferential direction changes. A lever is provided inside a casing of an image forming apparatus described later in which the process cartridge 1 is assembled. The protrusion 343 presses the rod according to the position in the circumferential direction. As will be described in detail later, the lever is movable between a first position and a second position. When the lever is pressed by the protrusion 343 to move from the first position to the second position, for example, the image forming apparatus recognizes that a new developing cartridge 3 is assembled.

After the developer cartridge 3 is assembled in the image forming apparatus, power is transmitted from the first gear portion 33 to the second gear portion 34 via the agitator. When the developer cartridge 3 is a new product, the reset gear 341 is rotated by the power described above. As the reset gear 341 rotates, the protrusion 343 of the reset gear 341 pushes down the lever. Thereby, the image forming apparatus recognizes the developing cartridge 3 as a new product. The teeth of the reset gear 341 are provided only on a part of the outer peripheral surface. Therefore, when the reset gear 341 rotates by a predetermined angle, the meshing of the gear teeth is loosened, and the reset gear 341 stops rotating. Therefore, even if the once-assembled developing cartridge 3 is assembled again, the reset gear 341 does not rotate.

The IC chip package 35 has an IC chip 351 and an IC chip holder 352 as a storage medium. The IC chip 351 has four electrical contact surfaces 353 . The electrical contact area 353 consists of a metal as a conductor. Also, the IC chip 351 can store various information related to the developing cartridge 3 . However, the number of electrical contact surfaces 353 that the IC chip 351 has may be 1 to 3, or may be 5 or more.

The IC chip holder 352 has a first outer surface 35A and a second outer surface 35B. The first outer surface 35A is located at one end of the IC chip holder 352 in the third direction. The second outer surface 35B is located at the other end of the IC chip holder 352 in the third direction. The first outer surface 35A is movable in the third direction relative to the second outer surface 35B.

More specifically, the IC chip holder 352 has a first holder member 361 , a second holder member 362 and a coil spring 363 between them. The first bracket member 361 is made of resin, for example. The second bracket member 362 is made of resin, for example. The first bracket member 361 has a first outer surface 35A. The IC chip 351 is fixed to the holding surface 360 included in the first outer surface 35A. The second bracket member 362 has a second outer surface 35B. In the assembled IC chip holder 352, the first outer surface 35A is separated from the second outer surface 35B in the third direction.

The coil spring 363 is an elastic member that expands and contracts in the third direction. The coil spring 363 is located between the first outer surface 35A and the second outer surface 35B in the third direction. The coil spring 363 may be directly connected to the first outer surface 35A and the second outer surface 35B, or may be indirectly connected via a connecting member. The coil spring 363 expands and contracts in the second direction at least between the first state and the second state contracted from the first state. The length in the third direction of the coil spring 363 in the first state is longer than the length in the third direction of the coil spring 363 in the second state. Therefore, the distance in the third direction between the first outer surface 35A and the second outer surface 35B in the first state is larger than the distance in the third direction between the first outer surface 35A and the second outer surface 35B in the second state. Long distance. Also, at least the length of the coil spring 363 in the second state in the third direction is shorter than the natural length of the coil spring 363 .

The second bracket member 362 has a cylindrical spring bracket 362A. The spring bracket 362A protrudes from the second bracket member 362 in the second direction. A coil spring 363 is inserted into this spring holder 362A. It should be noted that a cylindrical protrusion (not shown) is provided inside the spring holder 362A. The protruding portion is inserted inside the coil spring 363 . Thus, the coil spring 363 is supported by the outer peripheral surface of the protruding portion and the inner peripheral surface of the spring holder 362A.

The second bracket member 362 has a first claw portion 362B and a second claw portion 362C. The first claw portion 362B and the second claw portion 362C respectively protrude from the second bracket member 362 in a direction crossing with respect to the third direction. On the other hand, the first bracket member 361 has a first opening 361A. The first claw portion 362B is inserted into the first opening 361A. Also, the first bracket member 361 has a second opening not shown. The second opening is provided in the first bracket member 361 on the opposite side to the first opening 361A in the first direction. The second claw portion 362C is inserted into the second opening.

In the first state, the first claw portion 362B is in contact with the first bracket member 361 at the edge portion on the second outer surface 35B side of the first opening 361A. Also, in the first state, at the edge of the second opening on the second outer surface 35B side, the second claw portion 362C is in contact with the first bracket member 361 . Thereby, the length of the coil spring 363 in the third direction can be prevented from being longer than in the first state. Also, the first bracket member 361 may be prevented from being detached from the second bracket member 362 . On the other hand, in the second state, the first claw portion 362B and the second claw portion 362C are separated from the first bracket member 361 .

The IC chip 351 is fixed on the holding surface 360 included in the first outer surface 35A of the first holder member 361 . That is, as the first holder member 361 moves in the third direction relative to the second holder member 362 , the electrical contact surface 353 of the IC chip 351 also moves in the third direction. It should be noted that the IC chip 351 is fixed at a position recessed in the third direction from the first outer surface 35A toward the second holder member 362 .

The first bracket member 361 has a boss 37A, a boss 37B, and a boss 37C. The boss 37A, the boss 37B, and the boss 37C are provided on the outer surface of the first bracket member 361 crossing the first direction. The boss 37A and the boss 37B are provided on the outer surface of the first bracket member 361 facing the inner cover 371 . The boss 37A and the boss 37B extend in the first direction from the outer surface of the first bracket member 361 toward the inner cover 371 . On the other hand, the inner cover 371 has a through hole 371A and a through hole 371B. The through hole 371A and the through hole 371B penetrate the inner cover 371 in the first direction. The boss 37A is inserted into the through hole 371A. The boss 37B is inserted into the through hole 371B. It should be noted that the through hole 371A may be a concave portion into which the boss 37A can be inserted. Furthermore, the through-hole 371B may be a recess into which the boss 37B can be inserted.

The boss 37C is provided on the outer surface of the first bracket member 361 facing the housing 373 . The boss 37C extends in the first direction from the outer surface of the first bracket member 361 toward the housing 373 . On the other hand, the cover 373 has a through hole 373A. The through hole 373A penetrates the cover 373 in the first direction. The boss 37C is inserted into the through hole 373A. It should be noted that the through hole 373A may be a concave portion into which the boss 37C can be inserted.

The size (inner dimension) of the through hole 373A in the second direction is larger than the size (outer dimension) of the boss 37C in the second direction. The size (inner dimension) of the through hole 371A in the second direction is larger than the size (outer dimension) of the boss 37A in the second direction. Furthermore, the size (inner dimension) of the through hole 371B in the second direction is larger than the size (outer dimension) of the boss 37B in the second direction. Therefore, the IC chip holder 352 can move in the second direction with respect to the inner cover 371 and the outer cover 373 together with the boss 37A, the boss 37B, and the boss 37C. When the IC chip holder 352 moves in the second direction, the IC chip 351 having the electrical contact surface 353 also moves in the second direction together with the IC chip holder 352 .

The size of the through hole 373A in the third direction (inner size) is larger than the size of the boss 37C in the third direction (outer size). The size (inner dimension) of the through hole 371A in the third direction is larger than the size (outer dimension) of the boss 37A in the third direction. Furthermore, the size (inner dimension) of the through hole 371B in the third direction is larger than the size (outer dimension) of the boss 37B in the third direction. Therefore, the IC chip holder 352 can move in the third direction with respect to the inner cover 371 and the outer cover 373 together with the boss 37A, the boss 37B, and the boss 37C. When the IC chip holder 352 moves in the third direction, the IC chip 351 having the electrical contact surface 353 also moves in the third direction together with the IC chip holder 352 .

In addition, the inner cover 371 may have boss|hub 37A, 53B, and the 1st bracket member 361 may have through-hole 371A, 45B. Furthermore, the cover 373 may have a boss 37C, and the first bracket member 361 may have a through hole 373A.

<2. About the image forming device>

FIG. 4 is a longitudinal sectional view of the image forming apparatus 100 .

The image forming apparatus 100 is an electrophotographic printer (for example, an LED printer) that forms an image on printing paper using toner supplied from the process cartridge 1 . The image forming apparatus 100 has a housing 11 , a cover 12 and a plurality of LED units 13 .

The housing 11 has a plurality of slots 110 . Each slot 110 has an opening 111 capable of allowing insertion of the process cartridge 1 . The process cartridge 1 is inserted into the slot 110 through the opening 111 . Thus, the process cartridge 1 is assembled to the casing 11 . The process cartridge 1 is prepared for each color of toner. Therefore, the casing 11 has slots 110 for each color of toner. The image forming apparatus 100 uses four color toners of K (black), C (cyan), M (magenta), and Y (yellow). Therefore, the casing 11 of the image forming apparatus 100 has four slots 110. The four slots 110 are aligned in the third direction. The process cartridges 1 are inserted into the slots 110, respectively.

The cover 12 is a flat cover that covers the housing 11 . One end of the cover 12 in the third direction is rotatably connected to the housing 11 . The cover 12 is rotatable about a cover rotation axis 120 extending in a first direction between an open position and a closed position. The other end of the cover 12 in the third direction when the cover 12 is in the open position is farther from the housing 11 than the other end of the cover 12 in the third direction when the cover 12 is in the closed position.

The user of the image forming apparatus 100 arranges the cover 12 at the open position when assembling the process cartridge 1 to the casing 11 . When the cover 12 is disposed in the open position, the opening 111 of the slot 110 is open. Furthermore, the user of the image forming apparatus 100 arranges the cover 12 in the closed position when the assembly of the process cartridge 1 is completed. When the cover 12 is configured in the closed position, the opening 111 of the slot 110 is closed.

A plurality of LED units 13 are attached to a surface of the cover 12 facing the housing 11 . When the cover 12 is rotated around the cover rotation shaft 120 , the LED unit 13 also moves together with the cover 12 . The LED unit 13 is prepared for each process cartridge 1 . Therefore, the image forming apparatus 100 has four LED units 13 . Each LED unit 13 exposes the photosensitive drum 22 of each process cartridge 1 . Thus, an electrostatic latent image is formed on the outer peripheral surface of each photosensitive drum 22 .

The LED unit 13 is rotatable relative to the cover 12 between a retracted position (position indicated by a dashed-two dotted line in FIG. 4 ) and a protruding position (position indicated by a solid line in FIG. 2 ) farther from the cover 12 than the retracted position. When the cover 12 starts to rotate from the open position toward the closed position, each LED unit 13 moves from the retracted position to the projected position. Then, when the cover 12 further moves to the closed position with the LED unit 13 located at the projected position, the process cartridge 1 is further inserted into the slot 110 . At the same time, the LED unit 13 moves from a separation position at a predetermined distance from the photosensitive drum 22 to an exposure position in contact with the process cartridge 1 . At this time, the LED unit 13 moves to the exposure position while being guided by a guide member described later.

FIG. 5 is a diagram showing a state in which the process cartridge 1 is mounted on the socket 110 . Fig. 5 is a view viewed from a first direction. Also, in FIG. 5, the process cartridge 1 is indicated by a dotted line.

The process cartridge 1 is inserted into the slot 110 along the second direction. A guide portion 92 is arranged near the insertion port of the socket 110 . The guide portion 92 supports a metal electrical contact 93 capable of contacting the electrical contact surface 353 of the IC chip 351 . When the process cartridge 1 is inserted into the slot 110 , the electrical contact surface 353 of the IC chip 351 of the developing cartridge 3 contacts with the electrical contacts 93 .

In the middle of insertion of the process cartridge 1 , the first holder member 361 comes into contact with the guide portion 92 . The second bracket member 362 is pressed toward the guide portion 92 in the third direction by the frame of the housing 11 . Thereby, the first bracket member 361 and the second bracket member 362 approach in the third direction through the guide portion 92 . That is, the coil spring 363 is compressed compared to its natural length. When the insertion of the process cartridge 10 is completed and the electrical contact surface 353 is in contact with the electrical contacts 93, the first holder member 361 moves in the third direction toward the guide portion 92 by the elastic force of the coil spring 363 shorter than the natural length. As a result, the electrical contact surface 353 of the IC chip 351 is in contact with the electrical contact 93 . The control unit of the image forming apparatus 100 acquires necessary information from the IC chip 351 via the electrical contact surface 353 that is in contact with the electrical contact 93 .

<3.About attached cover>

The image forming apparatus 100 configured as described above is shipped, for example, with the process cartridge 1 attached to the attached cover when shipped from the factory. By attaching the cover to the process cartridge 1, the LED unit 13 can be stably positioned at the exposure position due to vibration during transportation, and the electrical contact surface 353 of the IC chip 351 can be protected. Hereinafter, the attached cover will be described.

FIG. 6 is a perspective view of the process cartridge 1 equipped with the attached cover 50 . FIG. 7 is a perspective view of the attached cover 50 .

The accessory cover 50 is made of resin, for example. The attached cover 50 has a bracket holding part 51 , a first coupling cover part 521 and a second coupling cover part 522 , an electrode cover part 53 , and an arm 54 .

The arm 54 extends in a first direction. The first coupling cover part 521 is located at one end of the arm 54 in the first direction, and the second coupling cover part 522 is located at the other end of the arm 54 in the first direction. The first coupling cover portion 521 extends in the second direction. When the accessory cover 50 is assembled to the process cartridge 1 , the first coupling cover portion 521 covers the drum coupling 231 and the developing coupling 331 . The second coupling cover portion 522 extends in the second direction. The second coupling cover portion 522 covers the second gear portion 34 .

The bracket holding portion 51 is located at one end of the arm 54 in the first direction and at one end of the first coupling cover portion 521 in the second direction. The holder holder 51 is attached to the IC chip holder 352 . The holder holding part 51 is attached to the outer cover 373 (see FIG. 2 ) which holds the IC chip holder 352 between the inner cover 371 and the inner cover 371 . The holder holder 51 holds the IC chip holder 352 from both sides in the second direction.

The bracket holding portion 51 has an insertion port 51A that opens toward the second coupling cover portion 522 in the first direction. The holder holder 51 is attached to the IC chip holder 352 through the insertion port 51A.

The holder holder 51 has an opening 56 at one end in the third direction. When the holder holding portion 51 is fitted to the housing 373 , the IC chip 351 is exposed from the opening 56 in the third direction.

The holder holding portion 51 has a chip protection portion 56A and a chip protection portion 56B that cover a part of the opening 56 from the third direction. The chip protection portion 56A and the chip protection portion 56B are respectively provided at edge portions of the opening 56 facing in the second direction. The chip protection portion 56A extends toward the chip protection portion 56B in the second direction. The chip protection portion 56B extends toward the chip protection portion 56A in the second direction. The chip protection portion 56A is separated from the chip protection portion 56B in the second direction. When the holder holding part 51 is mounted on the IC chip holder 352 , the space between the chip protection part 56A and the chip protection part 56B in the second direction faces the electrical contact surface 353 in the third direction.

The attached cover 50 attached to the IC chip holder 352 holds the IC chip holder in a state of pressing the first outer surface 35A of the IC chip holder 352 toward the second outer surface 35B and pressing the second outer surface 35B toward the first outer surface 35A. 352. In this state, in the third direction, the distance between the first outer surface 35A and the second outer surface 35B is the shortest. Accordingly, the first bracket member 361 and the second bracket member 362 do not move in the third direction with respect to the bracket holding portion 51 of the attached cover 50 . That is, expansion and contraction of the coil spring 363 can be suppressed. Furthermore, for example, it is possible to suppress the problem that the electric contact surface 353 contacts the outside and is damaged due to expansion and contraction of the coil spring 363 during shipment of the process cartridge 1 .

The second coupling cover portion 522 has a contact surface 55 along the second direction. When the accessory cover 50 is assembled to the process cartridge 1, the contact surface 55 faces the lever with which the protrusion 343 of the aforementioned reset gear 341 can contact in the third direction. Then, while the attached cover 50 is attached to the housing 11 in a state of being attached to the developing cartridge 3 attached to the drum cartridge 2 , the contact surface 55 contacts the lever to move the lever from the first position to the second position. The contact surface 55 has a first inclined surface 551 and a second inclined surface 552 , has a triangular shape when viewed from the first direction, and protrudes toward the rod facing in the third direction. When the accessory cover 50 is assembled to the process cartridge 1 , the second coupling cover portion 522 covers the reset gear 341 . The contact surface 55 of the second coupling cover portion 522 presses the lever instead of the protrusion 343 of the reset gear 341 . The function of the contact surface 55 will be described in detail later.

In addition, the second coupling cover portion 522 has a separation portion 57 . The separating portion 57 separates the photosensitive drum 22 from the developing roller 32 in a state where the attached cover 50 is attached to the developing cartridge 3 attached to the drum cartridge 2 .

The electrode cover portion 53 is located at one end portion of the second coupling cover portion 522 in the second direction. When the attached cover 50 is attached to the process cartridge 1, the electrode cover part 53 covers the developing electrode which is not shown in figure.

The process cartridge 1 can be attached to the socket 110 in a state where the attached cover 50 is attached.

<4.About the attached state of the cover>

FIG. 8 is a diagram showing a state in which the process cartridge 1 with the attached cover 50 is attached to the socket 110 . Fig. 8 is a sectional view viewed from a first direction. For convenience of illustration, hatching is omitted in FIG. 8 . Moreover, in FIG. 8, the process cartridge 1, the casing 11, and the cover 12 are indicated by dotted lines. 9 and 10 are diagrams showing a state in the middle of insertion of the process cartridge 1 to which the attached cover 50 is attached.

The slot 110 has a side surface 112 , a guide 113 , and a guide 114 facing in the third direction. The process cartridge 1 to which the attached cover 50 is mounted is inserted between the side surface 112 and the guides 113 and 114 . When the process cartridge 1 is inserted between the side surface portion 112 and the guide portions 113 and 114 , the contact surface 55 of the attached cover 50 attached to the process cartridge 1 comes into contact with the lever 15 .

FIG. 11 is a diagram for explaining the guide parts 113 and 114 and the rod 15 .

The guide part 113 and the guide part 114 are juxtaposed in the second direction with the space 115 vacated. The rod 15 is provided at a position facing the guide portion 113 in the third direction. The lever 15 moves between a first position shown in dashed lines in FIG. 11 and a second position shown in solid lines in FIG. 11 . When not pressed from the outside, the lever 15 is located at the first position, and when pressed from the outside, the lever 15 moves from the first position to the second position.

The housing 11 is provided with an optical sensor 16 that detects the lever 15 at the second position. When the image forming apparatus 100 is in use, the protrusion 343 of the reset gear 341 is in contact with the lever 15 . Thus, the lever 15 moves from the first position to the second position. Then, the optical sensor 16 detects that the lever 15 has moved to the second position. As a result, for example, the image forming apparatus 100 recognizes that a new developer cartridge 3 is assembled. It should be noted that, instead of the optical sensor 16, the position of the lever 15 may be detected by, for example, a touch sensor.

When the process cartridge 1 is inserted into the slot 110, the process cartridge 1 moves in the second direction along the first face 112A of the side portion 112 as shown in FIG. At this time, the second inclined surface 552 attached to the contact surface 55 of the cover 50 of the process cartridge 1 presses the lever 15 to move the lever 15 from the first position to the second position.

The second inclined surface 552 is parallel to the first surface 112A of the side surface portion 112 . Therefore, when the process cartridge 1 moves along the first surface 112A of the side portion 112 , the second inclined surface 552 keeps pressing the lever 15 . That is, the lever 15 is continuously located at the second position.

In addition, when the process cartridge 1 is inserted into the slot 110 , the process cartridge 1 moves in the third direction along the second surface 112B of the side surface 112 as shown in FIG. 10 . At this time, the lever 15 is pressed by the first inclined surface 551 of the contact surface 55 with the cover 50 . The first inclined surface 551 is parallel to the second surface 112B of the side surface 112 . Therefore, the first inclined surface 551 keeps pressing the lever 15 while the process cartridge 1 moves along the second surface 112B. That is, the lever 15 is continuously located at the second position.

Thus, during insertion of the process cartridge 1 equipped with the attached cover 50, the lever 15 is always located at the second position.

When the process cartridge 1 is inserted into the slot 110 and the cover 12 is rotated from the open position to the closed position, the LED unit 13 is inserted in the third direction toward the opposite side of the guide portions 113 , 114 from the process cartridge 1 . At this time, since a part of the lever 15 in the second position is located in the space 115 , insertion of the LED unit 13 into the space 115 can be prevented. That is, when the LED unit 13 moves from the separation position to the exposure position with the rotation of the cover 12 , it is guided from the separation position to the exposure position by a part of the lever 15 located at the second position. Thereby, it is possible to prevent erroneous mounting of the LED unit 13 in which the LED unit 13 is inserted into the space 115 .

In addition, even if the process cartridge 1 is slightly disengaged from the slot 110 due to vibration during transportation, for example, the state shown in FIG. 9 or FIG. Therefore, insertion of the LED unit 13 into the space 115 can be prevented by a part of the rod 15 . Thereby, even if vibration is received during transportation, the LED unit 13 can be stably positioned at the exposure position.

In addition, by attaching the cover 50 , it is possible to protect the electrical contact surface 353 and the electrical contact 93 by avoiding the contact between the electrical contact surface 353 of the developing cartridge 3 and the electrical contact 93 .

12 and 13 are diagrams showing a state in which the process cartridge 1 with the attached cover 50 is attached to the socket 110 . FIG. 12 is a diagram showing a state in the middle of insertion of the process cartridge 1 to which the attached cover 50 is attached. FIG. 13 is a diagram showing a state in which the insertion of the process cartridge 1 equipped with the attached cover 50 is completed. 12 and 13 are views viewed along the first direction.

The process cartridge 1 equipped with the attached cover 50 is inserted into the slot 110 in the second direction. A guide portion 92 is arranged near the insertion port of the socket 110 . The guide part 92 supports the electric contact 93 . When the process cartridge 1 is inserted into the slot 110 , the electrical contact surface 353 of the IC chip 351 of the developing cartridge 3 contacts with the electrical contacts 93 .

When the process cartridge 1 is not equipped with the attached cover 50 , the first bracket member 361 and the second bracket member 362 approach in the third direction through the guide portion 92 during insertion of the process cartridge 1 . In the case where the process cartridge 1 is equipped with the attached cover 50 , the IC chip holder 352 is held by the attached cover 50 in a state where the first outer surface 35A and the second outer surface 35B are closest to each other. Therefore, as shown in FIG. 8 , the process cartridge 1 can be inserted into the slot 110 so that the attached cover 50 does not come into contact with the guide portion 92 .

When the assembly of the process cartridge 1 to the socket 110 is completed, the electrical contact surface 353 moves to a position facing the electrical contact 93 in the third direction. The attached cover 50 holds the bracket 36 in a state in which expansion and contraction of the coil spring 363 is suppressed. Therefore, even after the insertion is completed, the first bracket member 361 does not move in the third direction toward the guide portion 92 . Moreover, the electrical contact surface 353 will not be in contact with the electrical contacts 93 .

In addition, in the third direction, the space between the chip protection portion 56A and the chip protection portion 56B in the second direction is located at a position facing the electrical contact surface 353 . Therefore, in the third direction, the accessory cover 50 is not located between the electrical contact surface 353 and the electrical contact 93 . Accordingly, even when the process cartridge 1 is mounted on the socket 110 , the electrical contacts 93 do not come into contact with the attached cover 50 .

In this way, the process cartridge 1 can be attached to the socket 110 even in the state where the attached cover 50 is attached. In addition, it is possible to avoid friction between the electrical contact surface 353 and the electrical contacts 93 . Furthermore, it is possible to protect the electrical contact 93 by avoiding contact between the electrical contact 93 and the attached cover 50 .

<5. Modifications>

As mentioned above, although one Embodiment of this invention was described, this invention is not limited to said embodiment. Hereinafter, various modification examples will be described focusing on differences from the above-described embodiment.

The accessory cover 50 may not be provided with the bracket holding portion 51 . That is, the additional cover 50 may not have the function of protecting the electrical contact surface 353 of the IC chip 351 . Furthermore, the contact surface 55 with the cover 50 has a triangular shape when viewed from the first direction, but is not limited thereto. The contact surface 55 only needs to have a shape capable of continuously pressing the lever 15 toward the second position when the process cartridge 1 with the attached cover 50 is inserted into the slot 110 .

In addition, in the above-described embodiment, the holder holder 51 holds the IC chip holder 352 in a state where the first holder member 361 and the second holder member 362 are closest to each other. However, it is only necessary that at least the coil spring 363 is not longer than the natural length when the holder holding portion 51 is mounted on the IC chip holder 352 .

In addition, in the above-described embodiment, the IC chip 351 having the electrical contact surface 353 is fixed to the outer surface of the IC chip holder 352 . However, it is also possible to fix only the electrical contact surface 353 that is in contact with the electrical contact 93 on the outer surface of the IC chip holder 352 , and arrange the parts other than the electrical contact surface of the IC chip 351 on other parts of the developing cartridge 3 .

In addition, in the above-described embodiment, the coil spring 363 is used as the elastic member. However, other types of springs such as leaf springs and torsion springs may be used instead of the coil springs 363 .

In addition, the shapes of the minute parts of the components constituting the image forming apparatus may be different from the shapes shown in the drawings of the present application. In addition, the respective elements appearing in the above-described embodiments or modified examples may be appropriately combined within a range that does not cause contradiction.

Label description

1: Process cartridge

2: drum cartridge

3: Developing cartridge

10: Process box

11: Shell

12: Hood

13: Exposure unit

15: Rod

16: Light sensor

21: Drum frame

22: Photosensitive drum

23: gear department

30: shell

31: Stirrer

32: Developing roller

33: First gear unit

34: Second gear unit

35: IC chip components

35A: First outer surface

35B: Second outer surface

36: Bracket

37A: Boss

37B: Boss

37C: Boss

45B: Through hole

50: with cover

51: Bracket holder

51A: Insertion port

53: Electrode cover

53B: Boss

54: arm

55: contact surface

56: opening

56A: Chip Protection Department

56B: Chip Protection Department

57: Separation Department

60: bracket cover

91: slot

92: Guidance Department

93: electrical contact

100: image forming device

110: slot

111: opening

112: side face

112A: First side

112B: Second side

113: Guidance Department

114: Guidance Department

115: space

120: cover rotation shaft

210: Recess

211: Frame Body

212: frame cover

213: one end

214: the other end

231: Drum Coupling

301: First side panel

302: Second side panel

303: Toner Room

304: opening

311: stirring shaft

312: mixing blade

321: Developer Roller Body

322: Developing Roller Shaft

331: Develop Coupling

332: Developer Roller Gear

341: Reset Gear

343: protrusion

351: IC chip

352: IC Chip Holder

353: Electrical contact surface

360: keep face

361: First bracket member

361A: First opening

362: Second bracket member

362A: Spring bracket

362B: First claw

362C: Second claw

363: Coil Spring

371: inner cover

371A: Through hole

371B: Through hole

372: Collar

373: Cover

373A: Through hole

521: First coupling guard

522: Second coupling guard

551: first inclined plane

552: second inclined plane

Claims (12)

1. An image forming device, characterized in that: A drum cartridge with a photosensitive drum; a developing cartridge, assembled to the drum cartridge, having a developing roller capable of rotating around a first shaft extending in a first direction, and a reset gear capable of rotating around a first shaft extending in the first direction an upwardly extending second shaft rotates and has a protrusion; a housing to which the developing cartridge in a state assembled to the drum cartridge is assembled, having an opening into which the developing cartridge in a state assembled to the drum cartridge can be inserted; a cover movable between a closed position closing the opening and an open position opening the opening; an LED unit for exposing the photosensitive drum, movable together with the cover, in an exposure position capable of exposing the photosensitive drum with the cover in the closed position, the LED unit is located at a separate position farther from the photosensitive drum than the exposure position with the cover in the open position; a rod capable of contacting the protrusion and movable between a first position and a second position; and a cover capable of being attached to the developing cartridge mounted on the drum cartridge, covering at least a part of the developing cartridge mounted on the drum cartridge, The accessory cover contacts the lever to move the lever from the first position to the second position while the developer cartridge in the attached state is attached to the housing. , A part of the lever guides the LED unit from the separation position to the exposure position in a state where the lever is located at the second position. 2. The image forming apparatus according to claim 1, wherein: During movement of the LED unit from the separation position to the exposure position accompanying movement of the cover from the open position to the closed position, a portion of the rod moves the LED unit from the A separation position leads towards said exposure position. 3. The image forming apparatus according to claim 1, wherein: The accessory cover has a separation part that separates the photosensitive drum from the developing roller in a state where the accessory cover is attached to the developing cartridge attached to the drum cartridge. 4. The image forming apparatus according to claim 1, wherein: An optical sensor that detects the lever at the second position is provided. 5. The image forming apparatus according to claim 1, wherein: The accessory cover has a contact surface along an insertion direction of the developing cartridge mounted on the drum cartridge with respect to the housing, and is fitted to the developing cartridge mounted on the drum cartridge. The contact surface is in contact with the lever to move the lever from the first position to the second position during assembly of the case to the housing. 6. The image forming apparatus according to claim 1, wherein: The developing cartridge has: a toner storage section capable of storing toner; and a developing coupling rotatable about a third axis extending in the first direction, positioned at one end of the toner storage portion in the first direction, The reset gear is located at the other end portion of the toner storage portion in the first direction. 7. The image forming apparatus according to claim 6, wherein: The developing cartridge has: a storage medium having an electrical contact surface; and a holder, located on one side of the toner storage portion in the first direction, to hold the electrical contact surface, the holder includes a first outer surface, a second outer surface, and an elastic member, the first outer surface The surface is located on one side of the third direction intersecting with the electrical contact surface, and the electrical contact surface is held, and the second outer surface is located on the other side of the third direction, and is located on the other side of the first outer surface. In the position separated in the third direction, the elastic member is located between the first outer surface and the second outer surface, is capable of stretching and contracting in the third direction, and is compatible with the first outer surface and the second outer surface. The second outer surface is connected, and the distance between the first outer surface and the second outer surface in the third direction changes through expansion and contraction of the elastic member, The accessory cover has a bracket cover attached to the bracket to cover at least a part of the bracket, and the bracket cover faces the first outer surface toward the bracket when the bracket cover is attached to the bracket. pressing the second outer surface and pressing the second outer surface toward the first outer surface, In a state where the bracket cover is separated from the bracket, the length of the elastic member in the third direction becomes a first length, The length of the elastic member in the third direction is a second length shorter than the first length in a state where the bracket cover is attached to the bracket. 8. The image forming apparatus according to claim 7, wherein: In a state where the bracket cover is fitted to the bracket, the electrical contact surface is separated from an inner surface of the bracket cover facing the electrical contact surface in the third direction. 9. The image forming apparatus according to claim 1, wherein: The drum cartridge has a drum coupling at one end of the photosensitive drum in the first direction, The accessory cover covers the drum coupling of the drum cartridge when attached to the developer cartridge in a state where the drum cartridge is assembled. 10. The image forming apparatus according to claim 6, wherein: The accessory cover covers the development coupling when attached to the development cartridge in a state in which the drum cartridge is assembled. 11. The image forming apparatus according to claim 1, wherein: The accessory cover covers at least a part of the reset gear when the developer cartridge is attached to the drum cartridge. 12. The image forming apparatus according to claim 7, wherein: having electrical contacts capable of contacting said electrical contact surface, When the developing cartridge is mounted on the casing in a state where the holder cover is not mounted on the holder, the electrical contacts are in contact with the electrical contact surfaces, When the developing cartridge is mounted on the image forming apparatus in a state where the holder cover is mounted on the holder, the electrical contact is located at a position separated from the electrical contact surface in the third direction.