A process cartridge and an image forming apparatus

Abstract

A processing cartridge comprises a cartridge body, a photosensitive drum arranged on the cartridge body, a charging roller arranged on the cartridge body, a spacer having a first position and a second position, the spacer locking the charging roller in an isolated position not in contact with the photosensitive drum when in the first position, the spacer being movable from the first position to the second position by a rotation of the charging roller in a first rotation direction, so that the spacer releases the locking of the charging roller, and the charging roller moves to a contact position in contact with the photosensitive drum under the action of an elastic member. The processing cartridge of the embodiment locks the charging roller in the isolated position by the spacer to prevent contact with the photosensitive drum, avoiding contact pollution therebetween. After installation and use, the charging roller automatically moves from the isolated position to the contact position with the photosensitive drum, eliminating the operation step of manually removing the spacer by the user, and improving the user experience.

Description

TECHNICAL FIELD

[0001] The present application relates to an image forming apparatus, and more particularly, to a process cartridge. BACKGROUND

[0002] An image forming apparatus forms an image on a recording material such as paper using an electrophotographic image forming process. Examples of the image forming apparatus include an electrophotographic copier, an electrophotographic printer, a facsimile machine, a word processor, and the like. A cartridge includes at least one of an electrophotographic photosensitive drum as a photosensitive member and a developing member such as a developing roller capable of acting on the drum, and the photosensitive member and the developing member can be integrally configured as a cartridge (may be referred to as a process cartridge) detachably installed in the image forming apparatus. A charging roller for contacting the photosensitive drum and charging the same is also included in the process cartridge.

[0003] After the process cartridge is produced, whether it is a random cartridge or a commodity cartridge, it will be stored for a period of time before shipment, and the storage environment temperature is generally relatively high. If the charging roller (CR) and the photosensitive drum (OPC) are in direct contact in the process cartridge, there is a certain probability that the CR will be contaminated by the OPC or the OPC will be contaminated by the CR after the storage experiment is completed (50°C, 21 days).

[0004] Most of the prior art is to manually add a spacer and a spacer paper between the CR and the OPC to achieve the purpose of isolation. When the user uses it, the spacer needs to be manually removed, which increases the user's use steps and reduces the user experience. SUMMARY

[0005] According to an aspect of the present application, a process cartridge for detachable installation in a main assembly of an image forming apparatus is provided, comprising:

[0006] a cartridge body;

[0007] a photosensitive drum provided on the cartridge body;

[0008] a charging roller provided on the cartridge body; the charging roller is arranged to be rotatable at least in a first rotation direction about an axis thereof;

[0009] a resilient member for urging the charging roller to move towards the photosensitive drum; and

[0010] a spacer provided at an end portion of the charging roller, the spacer having a first position and a second position, the spacer locking the charging roller in an isolated position in which the charging roller is not in contact with the photosensitive drum when in the first position; the spacer is movable from the first position to the second position by a rotational movement of the charging roller in the first rotation direction about an axis parallel to a length direction of the cartridge body, so that the spacer releases the locking of the charging roller, and the charging roller moves to a contact position in which the charging roller is in contact with the photosensitive drum under the action of the resilient member;

[0011] In the process of moving from the first position to the second position, the spacer only moves linearly in a direction perpendicular to the axis of the charging roller or only moves outward along the axis of the charging roller relative to the axis of the charging roller.

[0012] The processing cartridge of the embodiment locks the charging roller in the isolation position through the spacer when not installed and used, prevents contact with the photosensitive drum, and avoids contact pollution therebetween. After installation and use, the spacer is moved from the first position to the second position by the rotation of the charging roller, so that the charging roller is automatically moved from the isolation position to the contact position with the photosensitive drum, the operation step of manually taking out the spacer by the user is omitted, and the user experience is improved.

[0013] In some embodiments, when the spacer only moves linearly in a direction perpendicular to the axis of the charging roller, a transmission part is arranged on the spacer, the charging roller drives the spacer to move by contacting the transmission part, and the transmission relationship between the charging roller and the spacer is disconnected after the charging roller moves to a position away from the transmission part.

[0014] In some embodiments, the transmission part is a tooth, and the end of the charging roller is provided with a tooth that cooperates with the transmission part. The charging roller drives the spacer to move by the meshing of the teeth, and the transmission relationship between the charging roller and the spacer is disconnected after the teeth are disengaged.

[0015] In some embodiments, the spacer includes first and second spacers that move towards each other.

[0016] In some embodiments, the processing cartridge further includes a limiting stopper fixedly arranged on the cartridge body. The spacer is limited by the limiting stopper when in the first position, thereby locking the charging roller in the isolation position. The spacer is disengaged from the limiting stopper when moved to the second position, thereby releasing the locking of the charging roller.

[0017] In some embodiments, the processing cartridge further includes a first bearing arranged at the end of the charging roller. The first bearing is provided with an opening, and the spacer is arranged on the first bearing through the opening. The spacer can be accommodated in the first bearing after moving from the first position to the second position, and moves to the contact position with the first bearing and the charging roller.

[0018] In some embodiments, when the spacer only moves outward along the axis of the charging roller, the spacer is arranged to abut between the photosensitive drum and the charging roller when in the first position, so that the charging roller is locked in the isolation position not in contact with the photosensitive drum. When in the second position, the spacer is disengaged from the photosensitive drum, thereby releasing the locking of the charging roller.

[0019] In some embodiments, the isolator has a contact end that abuts against the photosensitive drum so that the isolator cannot rotate around the charging roller in the first position. The isolator is threaded onto the charging roller so that the isolator moves axially along the charging roller under the drive of the rotational movement of the charging roller in the first rotation direction, moving from the first position to the second position, thereby releasing the locking of the charging roller.

[0020] In some embodiments, the processing box further includes a second bearing disposed at the end of the charging roller, and an elastic element disposed between the second bearing and the box body.

[0021] In some embodiments, the end of the charging roller is provided with teeth such that when the processing cartridge is mounted into the main assembly of the image forming apparatus, the teeth at the end of the charging roller mesh with a drive gear in the main assembly, and the charging roller is driven by the drive gear to rotate in a first rotation direction.

[0022] In some embodiments, isolation elements are provided at both ends of the charging roller.

[0023] The present invention provides an image forming apparatus, including the processing box of any of the above. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the processing box according to Embodiment 1 of the present invention, wherein the isolation member is located in the first position;

[0025] Figure 2 for Figure 1 Enlarged view of point B in the middle;

[0026] Figure 3 This is a side view of the processing box according to Embodiment 1 of the present invention, wherein the separator is located in the first position;

[0027] Figure 4 This is a side view of the processing box according to Embodiment 1 of the present invention (the first bearing is omitted), wherein the isolation member is located in the first position;

[0028] Figure 5 This is a schematic diagram of the internal structure of the processing box according to Embodiment 1 of the present invention, wherein the charging roller is located in the isolation position;

[0029] Figure 6 This is a schematic diagram of the internal structure of the processing box in Embodiment 2 of the present invention (with the isolation components omitted).

[0030] Figure 7 This is a schematic diagram of the internal structure of the processing box according to Embodiment 2 of the present invention, wherein the isolation member is located in the first position;

[0031] Figure 8 This is a schematic diagram of the internal structure of the processing box in Embodiment 2 of the present invention, wherein the separator moves from the first position to the second position;

[0032] Figure 9 This is a schematic diagram of the internal structure of the processing box in Embodiment 2 of the present invention, wherein the isolation member is located in the second position;

[0033] Figure 10 This is a schematic diagram of the isolation component according to Embodiment 2 of the present invention. Detailed Implementation

[0034] The present invention will now be described in further detail with reference to the accompanying drawings.

[0035] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "fixation," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between the components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0036] Example 1

[0037] The image forming apparatus of this embodiment includes a main component and a processing box detachably mounted in the main component.

[0038] See Figures 1-5 The processing box includes a box body 1, a photosensitive drum 2, a charging roller 3, an elastic element 4, an isolation element 5, a limit block 6, a first bearing 7, and a second bearing 8.

[0039] In this embodiment, a three-dimensional Cartesian coordinate system is established, with the length direction of the housing 1 as the X-axis, the shortest line connecting the central axes of the charging roller 3 and the photosensitive drum 2 as the Y-axis, and the remainder as the Z-axis. The photosensitive drum 2 and the charging roller 3 are respectively arranged on the housing 1 along the X-axis and can rotate relative to the housing 1. The end faces at both ends of the housing 1 are parallel to the YZ plane. The elastic element 4 and the second bearing 8 are disposed inside the housing 1, and the isolating element 5, the limiting block 6, and the first bearing 7 are disposed at the end faces of the housing 1.

[0040] The charging roller 3 is configured to be able to rotate at least about the X-axis in the first rotational direction A (see...). Figures 3-4The first rotation direction A is the normal operating direction of the charging roller 3. In some embodiments, the image forming apparatus has a reversing function, which can drive the charging roller 3 to rotate around the X-axis in a second rotation direction opposite to the first rotation direction. The charging roller 3 has an isolated position and a contact position. In the isolated position, the charging roller 3 is isolated from the photosensitive drum 2 and does not contact it. In the contact position, the charging roller 3 contacts the photosensitive drum 2, thereby enabling it to charge the photosensitive drum 2. The charging roller 3 is configured to move from the isolated position to the contact position along the Y-axis. The portion of the charging roller 3 extending beyond the housing 1 has a ring of teeth. The teeth extend axially for a certain length and are used to interact with the isolator 5 and also to receive the drive of the drive gear 9 of the main component of the image forming apparatus.

[0041] The isolating element 5 is disposed at the end of the charging roller 3. In this embodiment, there are two sets of isolating elements 5, each set disposed at both ends of the charging roller 3. In this embodiment, each set of isolating elements 5 includes a first isolating element 51 and a second isolating element 52. The first isolating element 51 and the second isolating element 52 have the same structure and are disposed on both sides of the charging roller 3 along the Z direction and facing each other. The first isolating element 51 and the second isolating element 52 are provided with a transmission part 55. The charging roller 3 drives the first isolating element 51 and the second isolating element 52 to move towards each other by contacting the transmission part 55 (see reference). Figure 4 The transmission part 55 is toothed, and the end of the charging roller 3 is also toothed. The charging roller 3 drives the isolation member to move through the engagement of the teeth, and the transmission relationship with the isolation member is broken after the teeth disengage. In other embodiments, the transmission part 55 can also be a structure that provides friction, such as rubber with high friction.

[0042] The limiting block 6 is used to restrict the position of the isolating member, which can move relative to the limiting block 6 in the Z direction. When the isolating member is in the first position, it is limited by the limiting block 6, thereby locking the charging roller 3 in the isolated position. When the isolating member moves to the second position, it disengages from the limiting block 6, thereby releasing the locking of the charging roller 3.

[0043] The first bearing 7 is disposed at the end of the charging roller 3 and located on the outside of the housing 1. The first bearing 7 has an opening for the isolation member to pass through, so that the isolation member can be accommodated in the first bearing 7 after moving from the first position to the second position, and move with the first bearing 7 and the charging roller 3 to the contact position.

[0044] See Figure 5The second bearing 8 is disposed at the end of the charging roller 3 and located inside the housing 1. In this embodiment, the second bearing 8 is a conductive bearing. The elastic element 4 is disposed between the second bearing 8 and the housing 1 and is used to push the second bearing 8 to move along the Z direction. By pushing the second bearing 8, the charging roller 3 is indirectly pushed, causing it to move from the isolation position to the contact position along the Y direction. The elastic element 4 can be a spring.

[0045] When the processing box in this embodiment is not installed or in use, the first isolating member 51 and the second isolating member 52 respectively abut against the limiting block 6. Limited by the limiting block 6, the first isolating member 51 and the second isolating member 52 are also inserted into the first bearing 7, locking the first bearing 7 and the charging roller 3 in the isolated position. When the processing box is in use, it is installed into the main assembly of the image forming apparatus. The drive gear 9 in the main assembly meshes with the teeth at the end of the charging roller 3. The charging roller 3 receives the drive and rotates along the first rotation direction. The first isolating member 51 and the second isolating member 52 are driven by the charging roller 3 to move in opposite directions along the Z-axis (see...). Figure 3 and 4 (in the direction of the arrow), it retracts into the first bearing 7 and no longer abuts against the limiting block 6. The first bearing 7 is no longer subjected to the force from the first isolation member 51 and the second isolation member 52. At the same time, the elastic member 4 pushes the second bearing 8, and the second bearing 8 drives the charging roller 3 to move towards the photosensitive drum 2 along the Y direction. The first isolation member 51, the second isolation member 52, and the first bearing 7 all move synchronously with the charging roller 3 (refer to the direction of movement of the first bearing 7). Figure 3 (in the direction of the arrow), the charging roller 3 moves to the contact position that contacts the photosensitive drum 2 (see...). Figure 5 (In the direction of the arrow), ready to print.

[0046] After the charging roller 3 is driven to rotate in the first rotation direction, it interacts with the teeth of the first isolator 51 and the second isolator 52. The teeth push the first isolator 51 and the second isolator 52 to their final, unpullable position, i.e., to the end of the teeth of the first isolator 51 and the second isolator 52. At this position, the charging roller 3 disengages from the first isolator 51 and the second isolator 52 located inside the first bearing 7, and the transmission relationship is broken. At this point, even if the charging roller 3 continues to rotate in the first rotation direction (i.e., normal operating state) or reverses in the second rotation direction, it will not interact with the isolators, meaning the isolators will not affect the normal operation of the charging roller 3. This effect can be achieved by reasonably setting the length of the teeth on the first isolator 51 and the second isolator 52. This effectively avoids the risk of the isolators remaining in contact with the charging roller 3 after it has been released from locking, thus preventing interference with the rotation and wear of the charging roller 3. It also avoids the situation where the isolators get stuck inside the processing box in an image forming apparatus with a reversal function when the charging roller 3 reverses.

[0047] In this embodiment, when the processing box is not installed or used, the charging roller 3 is locked in an isolated position by an isolator to prevent it from contacting the photosensitive drum 2, thus avoiding contact contamination between the two. After installation and use, the rotation of the charging roller 3 drives the isolator to move from the first position to the second position, so that the charging roller 3 automatically moves from the isolated position with the photosensitive drum 2 to the contact position, eliminating the need for the user to manually remove the isolator and improving the user experience.

[0048] In other embodiments, the isolator may not be arranged along the Z-direction. For example, it may be arranged at a certain angle to the Z-direction on the YZ plane, as long as the isolator can lock the charging roller 3 in the isolated position. The isolator can move in other directions besides the Z-direction to release the locking of the charging roller 3. The isolator may also not be arranged along the YZ plane. The charging roller 3 may also not move towards the photosensitive drum 2 along the Y-direction, but may move towards the photosensitive drum 2 in other directions, as long as it can eventually make contact with the photosensitive drum 2. The isolator may also include only one of the first isolator 51 or the second isolator 52, as long as it can lock the charging roller 3 in the isolated position.

[0049] Example 2

[0050] The processing box in this embodiment is largely the same as that in Embodiment 1, except that the structure and arrangement of the isolation element 5 are different.

[0051] See Figures 6-10 The processing box in this embodiment includes a box body 1, a photosensitive drum 2, a charging roller 3, an elastic element 4, an isolation element 5, and a second bearing 8.

[0052] The end of the charging roller 3 extending outside the housing 1 has a ring of teeth for receiving drive from the drive gear 9 of the main component of the image forming apparatus. The end of the charging roller 3 inside the housing 1 has external threads for interacting with the isolator 5.

[0053] In this embodiment, there are two separators 5, which are respectively disposed at both ends of the charging roller 3. (See reference...) Figure 10 The isolator 5 is configured as a bracket with a threaded hole 53, which is sleeved on the end of the charging roller 3 through the threaded hole 53. The isolator 5 also has a contact end 54 that contacts and engages with the photosensitive drum 2. The contact end 54 can be an arc-shaped groove. The contact end 54 abuts against the arc-shaped surface of the photosensitive drum 2, thereby preventing the isolator 5 from rotating with the charging roller 3 in the first position, and allowing it to move only along the charging roller 3 in the X direction.

[0054] The second bearing 8 is disposed at the end of the charging roller 3 and located inside the housing 1. In this embodiment, the second bearing 8 is a conductive bearing, and the elastic element 4 is disposed between the second bearing 8 and the housing 1 to push the second bearing 8 to move along the Y direction. By pushing the second bearing 8, the charging roller 3 is indirectly pushed, causing it to move from the isolation position to the contact position along the Z direction. The elastic element 4 can be a spring. In other embodiments, the charging roller 3 may not move towards the photosensitive drum 2 along the Y direction, but may move towards the photosensitive drum 2 in other directions, as long as it can eventually make contact with the photosensitive drum 2.

[0055] The isolator 5 contacts the charging roller 3 via its internal thread. When the processing box is not installed or in use, the isolator 5 is in the first position, abutting between the photosensitive drum 2 and the charging roller 3, thus isolating the charging roller 3 in an isolated position where it does not contact the photosensitive drum 2 (see...). Figure 7 When the processing cartridge is installed into the main assembly of the image forming apparatus, the portion of the charging roller 3 extending outside the cartridge 1 engages with the drive gear 9 of the main assembly. The charging roller 3 is driven and rotates in the first rotation direction. The charging roller 3 applies force to the isolator 5 through its external thread. Since the contact end 54 of the isolator 5 abuts against the photosensitive drum 2, it cannot rotate with the charging roller 3, but can only move outward in the X direction towards the outside of the cartridge 1 (see...). Figure 8 The charging roller 3 moves from the first position to the second position, where it is disengaged from the photosensitive drum 2. Simultaneously, the elastic element 4 pushes the second bearing 8, which in turn drives the charging roller 3 to move along the Y direction toward the photosensitive drum 2. The isolating element 5 moves synchronously with the charging roller 3, and the charging roller 3 moves to the contact position where it contacts the photosensitive drum 2 (see [reference]). Figure 9 ), ready to print.

[0056] After leaving the first position, the isolator 5 disengages from the photosensitive drum 2 and stops moving along the X-axis, thus not interfering with the rotation of the photosensitive drum 2. The relationship between the isolator 5 and the charging roller 3 at the second position can be one of two things: first, the contact point between the charging roller 3 and the isolator 5 at the second position can be a smooth rod, i.e., without threads, so the isolator 5 does not rotate with the charging roller 3; second, the charging roller 3 can extend further at the contact point with the isolator 5 at the second position and be provided with external threads, in which case, due to friction, the isolator 5 can rotate with the charging roller 3. It should be noted that, in either case, even if the charging roller 3 continues to rotate in the first rotation direction (i.e., normal working state) or reverses in the second rotation direction, the isolator 5 will not move in the X direction, re-enter the first position, or move to another position, thereby affecting the normal operation of the charging roller 3 and the photosensitive drum 2. This effectively avoids the isolator 5 from still contacting the photosensitive drum 2 after the locking of the charging roller 3 is released, thus preventing the risk of affecting the rotation and wear of the photosensitive drum 2. It also avoids the situation where the isolator 5 gets stuck inside the processing box when the image forming apparatus with the reversal function is reversing the charging roller 3.

[0057] The above descriptions are merely some embodiments of the present invention. For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of the present invention, or the above technical solutions can be freely combined, including freely combining the technical features of the different embodiments described above; all of these fall within the protection scope of the present invention.

Claims

1. A processing box for detachable mounting in a main assembly of an image forming apparatus, characterized in that, include: Box body; A photosensitive drum is mounted on the housing; A charging roller is disposed on the housing; the charging roller is configured to be able to rotate at least about its axis in a first rotational direction. An elastic element for pushing the charging roller toward the photosensitive drum; as well as An isolator is disposed at the end of the charging roller. The isolator has a first position and a second position. When the isolator is in the first position, it locks the charging roller in an isolated position where it does not contact the photosensitive drum. The isolator is driven by the rotational movement of the charging roller about an axis parallel to the length direction of the housing along a first rotational direction, moving from the first position to the second position, so that the isolator releases the locking of the charging roller, and the charging roller moves to a contact position where it contacts the photosensitive drum under the action of the elastic member. During the movement from the first position to the second position, the isolator moves linearly only in a direction perpendicular to the axis of the charging roller, or moves outward only along the axis of the charging roller, relative to the axis of the charging roller.

2. The processing box according to claim 1, characterized in that, When the isolator moves linearly only in a direction perpendicular to the axis of the charging roller, the isolator is provided with a transmission part. The charging roller drives the isolator to move by contacting the transmission part, and disconnects the transmission relationship with the isolator after moving to a position where it is disengaged from the transmission part.

3. The processing box according to claim 2, characterized in that, The transmission part is a toothed part, and the end of the charging roller is provided with teeth that cooperate with the transmission part. The charging roller drives the isolation member to move through the meshing of the teeth, and disconnects the transmission relationship with the isolation member after the teeth disengage.

4. The processing box according to claim 2, characterized in that, The isolation components include a first isolation component and a second isolation component that move in opposite directions.

5. The processing box according to claim 2, characterized in that, It also includes a limiting block fixedly disposed on the box body. When the isolation member is in the first position, it is limited by the limiting block, thereby locking the charging roller in the isolation position. When the isolation member moves to the second position, it disengages from the limiting block, thereby releasing the lock on the charging roller.

6. The processing box according to claim 2, characterized in that, It also includes a first bearing disposed at the end of the charging roller, the first bearing having an opening, the isolation member being disposed on the first bearing through the opening, the isolation member being able to be accommodated in the first bearing after moving from the first position to the second position, and moving with the first bearing and the charging roller to the contact position.

7. The processing box according to claim 1, characterized in that, When the isolator moves outward only along the axis of the charging roller, the isolator is configured such that, in a first position, the isolator abuts between the photosensitive drum and the charging roller, locking the charging roller in an isolated position where it does not contact the photosensitive drum, and in a second position, the isolator disengages from the photosensitive drum, thereby releasing the locking of the charging roller.

8. The processing box according to claim 7, characterized in that, The isolator has a contact end that abuts against the photosensitive drum, so that the isolator cannot rotate around the charging roller in the first position. The isolator is threaded onto the charging roller, so that the isolator moves along the axial direction of the charging roller under the drive of the rotational movement of the charging roller in the first rotation direction, moving from the first position to the second position, thereby releasing the locking of the charging roller.

9. The processing box according to any one of claims 1 to 8, characterized in that, It also includes a second bearing disposed at the end of the charging roller, and the elastic element is disposed between the second bearing and the housing.

10. The processing box according to any one of claims 1 to 8, characterized in that, The charging roller is provided with teeth at its end, such that when the processing cartridge is installed in the main assembly of the image forming apparatus, the teeth at the end of the charging roller mesh with a drive gear in the main assembly, and the charging roller is driven by the drive gear to rotate in a first rotation direction.

11. The processing box according to any one of claims 1 to 8, characterized in that, The charging roller is provided with the isolation element at both ends.

12. An image forming apparatus, characterized in that, Includes the processing box according to any one of claims 1 to 11.

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