Process cartridge

Abstract

Disclosed in the present invention is a process cartridge. The process cartridge comprises: a drum unit comprising a second housing and a photosensitive drum; a developing unit comprising a first housing and a developing roller; a first coupling member; and a chip having a chip electrical contact surface, wherein the developing unit is movably connected to the drum unit, and is movable relative to the drum unit around the following poses: (a) a first pose in which the developing roller is in contact with the photosensitive drum; and (b) a second pose in which the developing roller is separated from the photosensitive drum; and when the process cartridge is located in the first pose and is positioned such that the developing roller and the photosensitive drum are located at the lower end of the process cartridge and a second axis is lower than a first axis, the developing unit can move to the second pose by means of its own weight.

Description

A process cartridge TECHNICAL FIELD

[0001] The present application relates to the technical field of electrophotographic imaging, and in particular to a process cartridge. BACKGROUND

[0002] A process cartridge and a process cartridge detachably mounted in an image forming apparatus are disclosed in the prior art, wherein the process cartridge comprises a first housing and a second housing, and a developing roller, a force receiving member and a partition member supported on the first housing, and a photosensitive drum supported on the second housing, when the process cartridge performs a printing task, the developing roller and the photosensitive drum are in pressure contact with each other, and the developing roller can deliver the developer carried thereon to the photosensitive drum to develop the latent image on the photosensitive drum; when the process cartridge does not perform a printing task, the force receiving member can receive a pushing force from the image forming apparatus to push the first housing to move relative to the second housing, and then the partition member supported on the first housing is moved to a position abutting against the second housing, so that the separation state of the developing roller and the photosensitive drum can be stably maintained; since the force receiving member and the partition member and other components need to be additionally provided in the process cartridge, the structure of the process cartridge becomes complex, the assembly efficiency is reduced, and the production cost is high. SUMMARY

[0003] To solve the above problems, the present application provides a new process cartridge, which is mainly realized by the following technical scheme:

[0004] A process cartridge having opposite left and right ends in a left-right direction, the process cartridge comprising:

[0005] a drum unit comprising a second housing and a photosensitive drum rotatable about a second axis extending in the left-right direction;

[0006] a developing unit comprising a first housing and a developing roller rotatable about a first axis extending in the left-right direction;

[0007] a first coupling member disposed at the right end of the process cartridge in the left-right direction and configured to receive an external force to drive the developing roller to rotate;

[0008] a chip having a chip electrical contact surface, the chip electrical contact surface and the photosensitive drum being arranged in an up-down direction crossing the left-right direction, the process cartridge having an upper end and a lower end in the up-down direction, the chip electrical contact surface being located at the upper end of the process cartridge, and the photosensitive drum being located at the lower end of the process cartridge;

[0009] the developing unit being movably connected to the drum unit and being movable relative to the drum unit about the following attitudes:

[0010] (a) a first attitude in which the developing roller is in contact with the photosensitive drum;

[0011] (b) a second attitude in which the developing roller is separated from the photosensitive drum;

[0012] When the process cartridge is positioned in the first attitude and in a position in which the developing roller is located at the lower end of the process cartridge and the second axis is lower than the first axis, the developing unit is movable to the second attitude by its own weight.

[0013] Further, the first coupling member is rotatable about a third axis, and the developing unit and the drum unit are movably coupled to each other by a coupling portion, the coupling portion being located above the third axis in the up-down direction.

[0014] Further, the first coupling member is rotatable about a third axis, and the developing unit and the drum unit are movably coupled to each other by a coupling portion, the first axis being located in front of the second axis in a front-rear direction intersecting the up-down direction and the left-right direction, and the coupling portion being located in front of the third axis in the front-rear direction.

[0015] Further, the developing unit and the drum unit are rotatably coupled to each other by a coupling portion, the coupling portion including a coupling hole provided on the developing unit and a coupling protrusion provided on the drum unit, the coupling protrusion being insertable into the coupling hole.

[0016] Further, the first coupling member is rotatable about a third axis, and the developing unit is rotatable relative to the drum unit about a fourth axis, the distance between the third axis and the fourth axis being greater than the distance between the third axis and the first axis in a direction perpendicular to the left-right direction.

[0017] Further, the developing unit is rotatable relative to the drum unit about a fourth axis, the distance between the fourth axis and the first axis being Y in the up-down direction, where 20 mm ≦ Y ≦ 45 mm.

[0018] Further, the developing unit is rotatable relative to the drum unit about a fourth axis, the distance between the fourth axis and the first axis being X in a front-rear direction intersecting the left-right direction and the up-down direction, where 14 mm ≦ X ≦ 26 mm.

[0019] Further, the second casing includes a first cover positioned at the right end of the process cartridge in the left-right direction, the first cover covering at least a portion of the first casing as viewed from the right end to the left end of the process cartridge, the first cover being provided with an exposure opening communicating with the outside of the process cartridge in a direction intersecting the left-right direction, at least a portion of the first coupling member being exposed outside the process cartridge through the exposure opening.

[0020] Further, the second casing includes a first cover positioned at the right end of the process cartridge in the left-right direction, the first cover covering at least a portion of the first casing as viewed from the right end to the left end of the process cartridge, the first cover being provided with an exposure opening communicating with the outside of the process cartridge in a direction intersecting the left-right direction, at least a portion of the first coupling member being exposed outside the process cartridge through the exposure opening.

[0021] Further, in the up-down direction, the limited portion is positioned at a lower end of the first coupling member.

[0022] Further, the process cartridge further includes a gear cover provided on the developing unit, the gear cover covering at least a portion of the first coupling member, the limited portion being configured as a protrusion provided on the gear cover, the limiting portion being configured as a hole provided on the first cover.

[0023] Further, the process cartridge further includes a support member provided at one end of the photosensitive drum in the left-right direction, the support member rotatably supporting the photosensitive drum on the second casing, the support member being configured to be movable relative to the second casing in a direction intersecting the left-right direction.

[0024] Further, the process cartridge further includes an elastic member applying a force to the support member so as to urge the support member to move in a direction approaching the developing roller in a direction intersecting the left-right direction.

[0025] Further, the first coupling member includes a coupling protrusion and a coupling gear provided separately, the coupling protrusion being configured to be movable relative to the coupling gear in a direction intersecting the left-right direction.

[0026] Further, the processing cartridge further comprises a damping part arranged on the developing unit, the damping part can inhibit the rotation of the first coupling member.

[0027] Further, the damping part is sponge or rubber or damping agent.

[0028] Further, the processing cartridge further comprises a time delay mechanism arranged at one end of the processing cartridge in the left-right direction, for prolonging the time required for the developing unit to move from the position where the developing roller is separated from the photosensitive drum to the position where the developing roller is in contact with the photosensitive drum.

[0029] Further, the time delay mechanism comprises a transmission gear, the transmission gear can move in response to the rotation of the first coupling member, to allow the developing unit to move from the second posture to the first posture.

[0030] Further, the transmission gear comprises a first transmission gear arranged on the developing unit and a second transmission gear arranged on the drum unit, the driving force outputted by the first coupling member can be transmitted to the first transmission gear and the second transmission gear in sequence.

[0031] Further, the second transmission gear is configured as a cogwheel with gear tooth part and cogwheel toothless part, when the developing unit is in the second posture, the gear tooth part of the second transmission gear is engaged with the first transmission gear to be in a first position, to receive driving force to rotate; when the developing unit is in the first posture, the cogwheel toothless part of the second transmission gear is opposite to the first transmission gear to be in a second position different from the first position.

[0032] Further, the second transmission gear can rotate along a fifth axis, the second transmission gear is recessed to form an avoiding part along the direction perpendicular to the fifth axis, when the developing unit is in the first posture, at least a part of the first transmission gear is accommodated in the avoiding part.

[0033] Further, the time delay mechanism further comprises a reset member, the reset member can apply force to the second transmission gear, so that the second transmission gear in the second position has a moving tendency to the first position.

[0034] The present application provides a processing cartridge, by changing the gravity center and swing gravity center of the developing unit, the developing roller can be separated from the photosensitive drum by the gravity of the developing unit, the rotation torque generated by the rotation of the first coupling member is applied on the developing unit, to realize the contact between the developing roller and the photosensitive drum, by the above configuration, the processing cartridge does not need to set force receiving rod and other components, greatly simplifies the structure of the processing cartridge, and reduces the production cost. BRIEF DESCRIPTION OF DRAWINGS

[0035] Fig. 1 is a schematic view of the process cartridge of Embodiment 1 of the present application from a certain angle;

[0036] Fig. 2 is a schematic view of the process cartridge of Embodiment 1 of the present application after the developing unit and the drum unit are separated;

[0037] Fig. 3 is a schematic view of the process cartridge of Embodiment 1 of the present application from another angle;

[0038] Fig. 4 is a schematic view of the process cartridge of Embodiment 1 of the present application when the developing roller and the photosensitive drum are separated;

[0039] Fig. 5 is a schematic view of the process cartridge of Embodiment 1 of the present application when the developing roller and the photosensitive drum are in contact;

[0040] Fig. 6 is a schematic view of the process cartridge of Embodiment 1 of the present application in cross section when the developing roller and the photosensitive drum are separated;

[0041] Fig. 7 is a schematic view of the process cartridge of Embodiment 1 of the present application in cross section when the developing roller and the photosensitive drum are in contact;

[0042] Fig. 8 is a schematic view of the process cartridge of Embodiment 2 of the present application from a certain angle;

[0043] Fig. 9 is a schematic view of the process cartridge of Embodiment 2 of the present application from another angle;

[0044] Fig. 10 is a schematic view of the process cartridge of Embodiment 3 of the present application from a certain angle;

[0045] Fig. 11 is a schematic view of the process cartridge of Embodiment 3 of the present application from another angle;

[0046] Fig. 12 is a schematic view of the process cartridge of Embodiment 3 of the present application in the position where the developing roller and the photosensitive drum are in contact and the position where they are separated;

[0047] Fig. 13 is a schematic view of the process cartridge of Embodiment 3 of the present application showing the operation of the time delay mechanism;

[0048] Fig. 14 is a schematic view of the process cartridge of Embodiment 3 of the present application showing a partial enlargement of the time delay mechanism;

[0049] Fig. 15 is a schematic view of the process cartridge of Embodiment 3 of the present application from still another angle;

[0050] Fig. 16 is a schematic view of the process cartridge of Embodiment 4 of the present application from a certain angle;

[0051] Fig. 17 is a schematic view of the process cartridge of Embodiment 4 of the present application after the first cover is separated from the housing;

[0052] Fig. 18 is a schematic view of the process cartridge of Embodiment 4 of the present application showing the drive side in exploded form;

[0053] Fig. 19 is a schematic view of the first cover in Embodiment 4 of the present application;

[0054] Fig. 20 is a schematic view of the process cartridge in Embodiment 4 of the present application;

[0055] Fig. 21 is another schematic view of the process cartridge in Embodiment 4 of the present application;

[0056] Fig. 22 is a schematic view of the process cartridge in Embodiment 5 of the present application;

[0057] Fig. 23 is a schematic view of the process cartridge in Embodiment 5 of the present application;

[0058] Fig. 24 is a schematic view of the process cartridge in Embodiment 5 of the present application;

[0059] Fig. 25 is a schematic view of the process cartridge in Embodiment 5 of the present application. DETAILED DESCRIPTION

[0060] Embodiment 1

[0061] For the purpose of describing the process cartridge 1000 in the present application, the directions of the process cartridge 1000 will be defined as follows. The first direction is the direction in which the axis of rotation of the developing roller 1001 (developing roller rotation axis) extends. The first direction is the direction in which the housing 1010 has opposite first and second ends, and the coupling member 1020 is disposed at the first end of the housing 1010. The second direction is the direction that intersects the first direction. The second direction is the direction in which the housing 1010 has opposite third and fourth ends, and the chip electrical contact surface 131a is disposed at the third end of the housing 1010, and the photosensitive drum 1002 is disposed at the fourth end of the housing 1010. The third direction is the direction that intersects the first and second directions.

[0062] As shown in Figs. 1-7, a process cartridge 1000 is disclosed in the present application, which is detachably installed in an image forming apparatus having a power supply member, an electrical contact, and a driving force applying member. In the present application, the image forming apparatus is an electrophotographic image forming apparatus (i.e., a printer).

[0063] The processing cartridge 1000 comprises a housing 1010, the housing 1010 has a first housing 1010a and a second housing 1010b connected with each other, wherein the first housing 1010a can accommodate a developer, the second housing 1010b comprises a first cover 1011 and a second cover respectively arranged at a first end and a second end of the housing 1010 and a main body part 1013 located at least partially between the first cover 1011 and the second cover, the first cover 1011 and the main body part 1013 are integrally formed, which makes it only need a set of molds in the process of producing the first cover 1011 and the main body part 1013, thus the production cost of the processing cartridge 1000 can be reduced, and in the process of assembling the processing cartridge 100, the first cover 1011 and the main body part 1013 also do not need to be additionally assembled, thus it also helps to improve the assembly efficiency of the processing cartridge 1000. Further, the first cover 1011, the second cover and the main body part 1013 are integrally formed, which can further reduce the production cost of the processing cartridge 1000 and improve the assembly efficiency of the processing cartridge 1000.

[0064] The processing cartridge 1000 further comprises a developing roller 1001 supported on the first housing 1010a, a photosensitive drum 1002 supported on the second housing 1010b and a charging roller (not shown in the drawings), wherein when the processing cartridge 1000 performs a printing work, the developing roller 1001 carries a developer, the charging roller can uniformly charge the photosensitive drum 1002, the charged photosensitive drum 1002 can form an electrostatic latent image on the outer surface of the photosensitive drum 1002 after being selectively irradiated by a laser in an image forming apparatus, the developing roller can deliver the developer carried thereon to the photosensitive drum 1002 to develop the electrostatic latent image thereon and form a developer image on the photosensitive drum 1002 through the contact with the photosensitive drum 1002, then the developer image can be transferred to a transfer belt through the contact between the photosensitive drum 1002 and the transfer belt, finally, the transfer belt can transfer the developer image to a recording medium (such as paper). The processing cartridge 1000 further comprises a first coupling member 1020 supported on the first housing 1010a and a second coupling member 1009 arranged on the second housing 1010b, the first coupling member 1020 and the second coupling member 1009 are both located at the first end of the housing 1010, the first cover 1011 can cover at least a part of the first coupling member 1020 to position the first coupling member 1020, the first coupling member 1020 can be coupled with a first driving force applying member of the image forming apparatus to receive a rotational driving force output by the first driving force applying member to rotate, thereby driving the developing roller 1001 to rotate, the second coupling member 1009 can be coupled with a second driving force applying member of the image forming apparatus to receive a driving force output by the second driving force applying member to rotate, thereby driving the photosensitive drum 1002 to rotate.

[0065] The process cartridge 1000 also includes an electrode having an electrode electrical contact surface that is electrically contactable with a power supply component of the image forming device, the electrode electrical contact surface being disposed at the second end of the housing 1010 in the first direction, the electrode electrical contact surface being configured to supply power to the charging component, that is, the electrode is configured to receive power from the image forming device and supply the received power to the charging component to ensure that the charging component is able to charge the photoconductive drum 1002. Furthermore, the process cartridge 1000 includes a chip 1031 having a chip electrical contact surface 1031a that is electrically contactable with an electrical contact of the image forming device, the chip electrical contact surface 1031a being disposed at the first end of the housing 1010 in the first direction, that is, the chip electrical contact surface 1031a is disposed at the same end of the housing 1010 as the first coupling member 1020 or the second coupling member 1009 in the first direction.

[0066] In order to avoid the deformation of the outer surface of the developing roller 1001 caused by the long time contact between the developing roller 1001 and the photosensitive drum 1002, and thus the image deterioration, when the process cartridge 1000 does not need to perform the printing task, the developing roller 1001 should be kept separated from the photosensitive drum 1002 as much as possible. For this purpose, the embodiment 1 changes the rotation / oscillation center of the first shell 1010a of the process cartridge 1000 relative to the second shell 1010b. Specifically, as shown in FIG. 2, the first end of the shell 1010 in the first direction is provided with a connecting portion, which includes a first positioning column 1011a and a first positioning hole 1059a matched with each other. The first positioning column 1011a can be matched and inserted into the first positioning hole 1059a, and the two keep the gap cooperation. The first positioning column 1011a is arranged on the first cover 1011 of the second shell 1010b, and the first positioning hole 1059a is arranged on the gear cover 1059 or the bearing plate 1060 of the first shell 1010a. Preferably, the first positioning hole 1059a is arranged on the gear cover 1059 of the first shell 1010a. The developing unit 1051 (including the first shell 1010a and the developing roller 1001 and other components) is connected to the drum unit 1052 (including the second shell 1010b and the photosensitive drum 1002 and other components) through the positioning and supporting cooperation of the first positioning hole 1059a and the first positioning column 1011a. Correspondingly, the developing unit 1051 is supported by the drum unit 1052, and the developing unit 1051 can rotate / oscillate relative to the drum unit 1052 with the first positioning hole 1059a or the first positioning column 1011a as the center, that is, the center axis of the first positioning hole 1059a or the first positioning column 1011a matches the rotation axis of the developing unit 1051 relative to the drum unit 1052. In this embodiment, it can also be said that the first shell 1010a can rotate / oscillate relative to the second shell 1010b with the first positioning hole 1059a or the first positioning column 1011a as the center, and the center axis of the first positioning hole 1059a or the first positioning column 1011a matches the rotation axis of the first shell 1010a relative to the second shell 1010b. Alternatively, the first positioning column 1011a can also be arranged on the gear cover 1059 or the bearing plate 1060 of the first shell 1010a, and the first positioning hole 1059a can also be arranged on the first cover 1011 of the second shell 1010b. Therefore, this is not limiting.

[0067] Specifically, since the first positioning hole 1059a and the first positioning post 1011a are in a matching relationship with each other, the positions of the first positioning hole 1059a and the first positioning post 1011a in the second direction (for the convenience of understanding, the second direction will be described as the up-down direction hereinafter) and the third direction (for the convenience of understanding, the second direction will be described as the front-rear direction hereinafter) in the process cartridge 1000 are substantially the same, therefore, the position of the first positioning hole 1059a will be described hereinafter, in general, the first positioning hole 1059a should be as far away from the developing roller 1001 as possible, so as to provide a long enough torque, so that the developing unit 1051 can be separated to the separated position with a smaller weight, i.e. closer to the upper end of the first housing 1010a in the up-down direction and closer to the front end of the first housing 1010a in the front-rear direction, further, the distance between the central axis A2 of the first positioning hole 1059a and the rotation axis A1 of the first coupling member 1020 is greater than the distance between the developing roller rotation axis A3 of the developing roller 1001 and the rotation axis A1 of the first coupling member 1020; first, in the up-down direction, the first positioning hole 1059a is located at the upper end of the first cover 1011, and specifically, the first positioning hole 1059a is located above the rotation axis A1 of the first coupling member 1020 in the up-down direction, more specifically, as shown in FIG. 7, when the developing roller 1001 is in the contact position, i.e. the developing unit 1051 is in the first attitude, in the up-down direction, the distance between the central axis A2 of the first positioning hole 1059a and the developing roller rotation axis A3 of the developing roller 1001 is Y, wherein 20mm≦Y≦45mm, more preferably, 30mm≦Y≦38mm, when Y is within the above range, the separating effect is better. In the front-rear direction, the first positioning hole 1059a is arranged at the front end of the first housing 1010a, and specifically, the first positioning hole 1059a is arranged at the front end of the rotation axis A1 of the first coupling member 1020, more specifically, in the front-rear direction, the distance between the central axis A2 of the first positioning hole 1059a and the developing roller rotation axis A3 of the developing roller 1001 is X, wherein 14mm≦X≦26mm, more preferably, 18mm≦X≦22mm, when X is within the above range, the separating effect is better.

[0068] Further, the rotation center of the developing unit 1051 is arranged at the above-mentioned position in the process cartridge 1000, thus, when the developing roller 1001 is ready to move toward the separation position, the first coupling member 1020 will be interfered by the exposure opening 1012 arranged on the first cover 1011 and cannot move, which results in that the developing unit 1051 cannot move and the developing roller 1001 cannot reach the separation position. Therefore, in order to solve the problem and facilitate the normal separation of the developing roller 1001 from the photosensitive drum 1002, at least a part of the first coupling member 1020 is movably arranged in the exposure opening 1012. Further, the exposure opening 1012 is configured as a circular hole, and the diameter of the exposure opening 1012 is greater than that of the supported surface 1020b of the first coupling member 1020, which is a circumferential surface. As a preferred, in order to solve the problem and facilitate the normal separation of the developing roller 1001 from the photosensitive drum 1002, the difference between the diameter of the exposure opening 1012 and that of the supported surface 1020b of the first coupling member 1020 is 0.5mm-6mm, more preferably, the difference between the diameters is 1mm-3mm, which has the best separation effect in the range, which effectively avoids the problem that the first coupling member 1020 cannot move enough to separate the developing roller 1001 from the photosensitive drum 1002 due to the small difference between the diameters, and also avoids the problem that the developing unit 1051 cannot rotate to a contact position where the developing roller 1001 contacts the photosensitive drum 1002 due to the large difference between the diameters.However, as another alternative embodiment in the present embodiment, the exposure opening 1012 can also be unchanged in size as in the prior art, that is, the diameter difference between the exposure opening 1012 and the supported surface 1020b of the first coupling member 1020 can also be less than 0.5 mm, in which case, to achieve the separation of the developing roller 1001, a cross-coupling structure (which can be referred to as a cross slider coupling) can also be provided in the process cartridge 1000, since the cross-coupling structure belongs to a well-known technology, therefore, it will not be described in detail here, and only a brief introduction will be made for the specific implementation structure, that is, the developing coupling protrusion 1020a and the coupling gear 1020c are connected by a connecting slider (not shown), that is, the coupling protrusion 1020a and the coupling gear 1020c of the first coupling member 1020 are provided separately, and during the movement and separation of the developing unit 1051, the developing coupling protrusion 1020a will always be coupled with the driving force applying member of the image forming apparatus, and the position of the coupling protrusion 1020a in the process cartridge 1000 will hardly move, but the connecting slider and the coupling gear 1020c will move with the movement of the developing unit 1051, avoiding the movement of the developing unit 1051 being inhibited, therefore, through this cross-coupling structure, the above technical effects can be achieved without increasing the diameter of the exposure opening 1012; and, in another alternative embodiment, in the case where the coupling protrusion 1020a and the coupling gear 1020c of the first coupling member 1020 are provided separately, the connection can also be achieved through a universal joint structure that can tilt and swing relative to the left-right direction, that is, the universal joint structure has a tilt position and a righting position, when the developing roller 1001 moves towards the separation position, the universal joint can be moved from the righting position to the tilt position, so that the movement of the developing unit 1051 is not inhibited without changing the position of the coupling protrusion 1020a in the process cartridge 1000.

[0069] Further, the process cartridge 1000 further comprises a limiting surface (not shown in the figure) and a limited surface (not shown in the figure) that cooperate with each other, the limiting surface and the limited surface can be used to limit the rotation / pivoting distance of the first housing 1010a relative to the second housing 1010b after contacting each other, thereby stabilizing the separation distance of the developing roller 1001 and the photosensitive drum 1002, wherein one of the limiting surface and the limited surface is provided on the first housing 1010a, and the other is provided on the second housing 1010b, and the positions of the limiting surface and the limited surface are also not limited, as long as they can contact each other to limit the rotation / pivoting distance of the first housing 1010a relative to the second housing 1010b.

[0070] Of course, the left end of the process cartridge 1000 is also provided with similar structure as the first positioning post and the first positioning hole, which is substantially the same as the structure and position of the first positioning hole 1059a and the first positioning post 1011a at the right end of the process cartridge 1000, i.e. the first positioning hole 1059a and the first positioning post 1011a at the left end and the right end are coaxially arranged, and the detailed description will not be repeated herein.

[0071] When the process cartridge 1000 does not perform a task or the process cartridge 1000 is positioned such that the photosensitive drum 1002 is positioned at the lower end of the process cartridge 1000 and the photosensitive drum rotation axis A4 of the photosensitive drum 1002 is positioned at the lower end of the developing roller rotation axis A3 of the developing roller 1001, the weight (self-weight) of the developing unit 1051 relative to the center of gravity 1099 of the developing unit 1051 generates a moment (R1 direction in FIG. 7) around the first positioning post 1011a, so that the developing roller 1001 and the photosensitive drum 1002 are separated from each other, at this time, the developing unit 1051 is in the second posture, and the separation distance d between the developing roller 1001 and the photosensitive drum 1002 can be stably maintained by the contact between the limiting surface and the limited surface, therefore, as the process cartridge 1000 adopting the structure, the developing roller 1001 can be stably maintained at the separation position when the process cartridge 1000 does not perform a printing task, and further, the deformation of the surface elastic layer of the developing roller 1001 caused by the contact between the developing roller 1001 and the photosensitive drum 1002 can be inhibited. When the process cartridge 1000 needs to perform a printing task, the first coupling member 1020 can receive the driving force of the image forming apparatus to rotate in the R2 direction opposite to the R1 direction, and the rotational torque generated thereby is applied to the developing unit 1051, so that the state balance of the developing roller 1001 in the separation position is broken, thereby causing the developing unit 1051 to rotate around the first positioning post 1011a in the R2 direction, and further, causing the developing roller 1001 to maintain contact with the photosensitive drum 1002; when the imaging is completed, i.e. the process cartridge 1000 no longer continues to perform a printing task, the first coupling member 1020 stops rotating, and the rotational torque applied to the developing unit 1051 disappears, at this time, the self-weight of the developing unit 1051 can again cause the developing unit 1051 to rotate around the first positioning post 1011a, so that the developing roller 1001 and the photosensitive drum 1002 are separated from each other.

[0072] In general, the embodiment provides a process cartridge 1000, by changing the center of gravity and the swing center of the developing unit 1051, the developing roller 1001 and the photosensitive drum 1002 can be separated from each other by the self-gravity of the developing unit 1051, the rotational torque generated by the rotation of the first coupling member 1020 is applied to the developing unit 1051, so that the developing roller 1001 and the photosensitive drum 1002 are in contact, by the above structure, the process cartridge 1000 no longer needs to be provided with a force receiving rod and other components, the structure of the process cartridge 1000 is greatly simplified, and the production cost is reduced.

[0073] Embodiment 2

[0074] Next, the embodiment 2 of the present application is introduced, as shown in FIG. 8-9, the embodiment 2 discloses a processing cartridge, the same as the processing cartridge in the embodiment 1, for example, the developing unit still relies on its own gravity to achieve the separation of the developing roller and the photosensitive drum, and relies on the rotation of the developing connecting part 1120 to achieve the contact of the developing roller and the photosensitive drum, the difference is that the positions of the chip 1131 and the electrode 1113 in the processing cartridge 1100 are different.

[0075] The electrode 1113 of the processing cartridge 1100 is arranged on the second cover 1112 of the second shell 1110b, the electrode 1113 has an electrode electric contact surface 1113a which can be electrically contacted with the power supply part of the image forming device, in the first direction, the electrode electric contact surface 1113a is arranged at the second end of the shell 1110 and at least partially faces upward of the shell 1110, the electrode electric contact surface 1113a is configured to be able to supply the power to the charging roller, that is, the electrode 1113 can receive the power of the image forming device and supply the received power to the charging roller, so as to ensure that the charging roller can charge the photosensitive drum. Moreover, the chip 1131 of the processing cartridge 1100 has a chip electric contact surface 1131a which can be electrically contacted with the electric contact of the image forming device, in the left-right direction, the chip electric contact surface 1131a is arranged at the left end of the shell 1110, that is, the chip electric contact surface 1131a and the electrode electric contact surface 1113a are both arranged at the left end of the shell 1110, while in the first direction, the first coupling part 1120 is arranged at different sides of the shell 1110, which can make the chip electric contact surface 1131a further away from the first coupling part 1120 in the left-right direction, reduce the influence of the vibration generated by the first coupling part 1120 when rotating on the stability of the electric contact between the chip electric contact surface 1131a and the electric contact of the image forming device, and in the first direction, the chip electric contact surface 131a is arranged at a position further away from the right end of the shell 1110 than the electrode electric contact surface 1113a.

[0076] Embodiment 3

[0077] As shown in FIG. 10-15, a processing cartridge 1300 in the embodiment 3 of the present application is shown, the processing cartridge 1300 is the same as the processing cartridge in the above-mentioned embodiment 2, for example, the processing cartridge 1300 also completes the separation of the developing roller and the photosensitive drum by the weight (i.e. gravity) of the developing unit itself, and achieves the contact of the developing roller and the photosensitive drum by the torque of the developing rotating part in the developing unit, therefore, for this part of structure and function, this embodiment will not be described again, the difference is that the first cover 1352 and the second cover 1351 and other structures and gear trains of the processing cartridge 1300 are different, the part of structure will be described in detail next.

[0078] The first cover 1352 of the process cartridge 1300 is provided with a first exposure opening 1352a, which can also be referred to as a notch, through which at least a portion of the first coupling member 1320 is exposed outside the process cartridge 1300 in the first direction to receive a rotational driving force from the image forming device to drive the developing roller 1309 and the powder feeding roller 1302 to rotate. In a direction crossing the first direction, the first exposure opening 1352a communicates with the outside of the first cover 1352, specifically, in the third direction (i.e. the direction in which the process cartridge 1300 and the tray are installed together into the image forming device when the process cartridge 1300 is supported on the tray of the image forming device), the first exposure opening 1352a opens in a direction away from the photosensitive drum axis, in other words, in the installation direction of the process cartridge 1300, the first exposure opening 1352a opens toward the downstream side of the installation direction of the process cartridge 1300. With this configuration, the developing unit can be more easily assembled to the drum unit in a direction crossing the first direction, so that interference of the developing unit with the first cover 1352 when installed in a direction crossing the first direction can be avoided. Therefore, based on this structure of the first exposure opening 1352a, the assembly efficiency of the process cartridge 1300 can be greatly improved.

[0079] Since the drum roller separation in the present embodiment is realized by the gravity of the developing unit, the separation distance between the developing roller 1309 supported on the developing unit and the photosensitive drum of the drum unit should be appropriate under the condition that the developing unit is not subjected to other external forces, so the process cartridge 1300 in the present embodiment is further provided with a limiting mechanism for limiting the swing distance of the developing unit after separation, so as to keep the developing roller 1309 of the developing unit at an appropriate distance from the photosensitive drum, and the limiting mechanism is preferably arranged at both ends of the process cartridge 1300 in the left-right direction, and the limiting mechanisms at both ends of the process cartridge 1300 are substantially the same in structure, so the limiting mechanism at the right end of the process cartridge 1300 will be taken as an example for description below. Specifically, the limiting mechanism comprises a limiting part 1353 arranged on the gear cover 1359 of the developing unit and configured as a protrusion, and a limiting hole 1352b arranged on the first cover 1352 and a limiting part 1352c formed on the inner surface of the limiting hole 1352b and configured as a surface, and in the second direction, the limiting part 1353 and the limiting part 1352c are located at the lower end of the first coupling 1320, and more specifically, the limiting part 1353 and the limiting part 1352c are located at the lower end of the developing roller axis A3, and more specifically, as shown in FIG. 15, in the state that the developing unit is not subjected to the force from the outside of the process cartridge 1300 (hereinafter referred to as the predetermined state of the process cartridge 1300), the distance P2 between the rotation axis A2 of the developing unit and the limiting part 1352c is greater than or equal to the distance P1 between the rotation axis A2 of the developing unit and the developing roller axis A3, and in the third direction, the limiting part 1353 and / or the limiting part 1352c has an overlapping part with the first coupling 1320, the limiting part 1353 can be inserted into the limiting hole 1352b and contact with the limiting part 1352c in the state that the developing roller 1309 is separated from the photosensitive drum, so that the tendency of the lower end of the developing unit moving away from the photosensitive drum is inhibited, at this time, the interval distance between the developing roller 1309 and the photosensitive drum will remain stable and have an appropriate distance; as an optional structure, the limiting hole 1352b can be arranged on the developing unit, and correspondingly, the limiting part 1353 is arranged on the first cover 1352, so this is not limiting.

[0080] As described in the foregoing embodiments, when the process cartridge 1300 needs to perform a printing task, the first coupling member 1320 starts to rotate, and the developing unit can swing toward the drum unit by the torque generated by the rotation of the first coupling member 1320 to achieve the re-contact between the developing roller 1309 and the photosensitive drum, and then the printing can be achieved. However, if the developing roller 1309 contacts the photosensitive drum too fast, at the position where the photosensitive drum and the developing roller 1309 contact each other, the outer surface of the photosensitive drum has not been charged by the charging member, and there is no potential difference to inhibit the transfer of the developer carried on the developing roller 1309 to the photosensitive drum, which can cause the developer carried on the developing roller 1309 to be transferred to the photosensitive drum, so that the developer on the photosensitive drum is transferred to the transfer belt of the image forming apparatus, and the contaminated transfer belt finally transfers the developer to the paper, causing the decline of the printing quality. Based on this potential problem, the embodiment proposes an improvement scheme, that is, the process cartridge 1300 further comprises a time delay mechanism, which is designed to delay the time when the developing roller 1309 contacts the photosensitive drum after the first coupling member 1320 starts to rotate, so as to avoid the above-mentioned problem. Specifically, as shown in FIGS. 13-14, the time delay mechanism comprises a first transmission gear 1303, a second transmission gear 1304 and a reset member 1305, wherein the first transmission gear 1303 is installed on the developing unit and has a first gear tooth 1303b in contact with the gear tooth portion 1320c of the first coupling member 1320, and can receive the output rotary driving force thereof, so that the first transmission gear 1303 rotates, and the first transmission gear 1303 further comprises a second gear tooth 1303a coaxial with the first gear tooth 1303b and farther away from the left end of the process cartridge 1300 in the first direction than the first gear tooth 1303b; the second transmission gear 1304 is installed on the first cover 1352 through a connecting portion 1352d configured as an elastic buckle, that is, the second transmission gear 1304 does not move with the swing of the developing unit, the second transmission gear 1304 comprises a second transmission gear tooth 1304a which can be in contact and engaged with the second gear tooth 1303a, and the second transmission gear 1304 can rotate, but the second transmission gear tooth 1304a does not extend along the circumference 360 degrees of the second transmission gear 1304, that is, the second transmission gear 1304 is not a full-tooth gear, but a missing-tooth gear. As shown in FIG. 13(a), in the case where the developing roller 1309 is separated from the photosensitive drum, the second transmission gear tooth 1304a is in the state of being in contact and engaged with the second gear tooth 1303a, and at this time, the second transmission gear 1304 is in the initial position.The second transmission gear 1304 further comprises a receiving portion 1304b, which is located at the downstream side of the second transmission gear teeth 1304a and adjacent to the gear teeth of the downstream side of the second transmission gear teeth 1304a in the rotation direction of the second transmission gear 1304, the second transmission gear teeth 1304a are configured to be concave from the outer circumferential surface of the second transmission gear 1304 towards the direction close to the rotation axis of the second transmission gear 1304, at least a part of the receiving portion 1304b is closer to the rotation axis of the second transmission gear teeth 1304a than the second transmission gear teeth 1304a in the direction perpendicular to the rotation axis of the second transmission gear 1304, in the state that the developing roller 1309 keeps in contact with the photosensitive drum, as shown in Fig. 13(c), the receiving portion 1304b can be used to accommodate at least a part of the second gear teeth 1303a, so that the second gear teeth 1303a keeps spaced from the second transmission gear teeth 1304a, thereby making the rotation driving force of the first transmission gear 1303 unable to be transmitted to the second transmission gear 1304, at this time, the second transmission gear 1303 will keep in the static state and be in the termination position; the delay mechanism further comprises the reset member 1305 mentioned above, at least one end of the reset member 1305 abuts against the second transmission gear 1304, so that the reset member 1305 can exert a force on the second transmission gear 1304 along the direction opposite to the rotation direction of the second transmission gear 1304, thereby when the developing roller 1309 is separated from the photosensitive drum again, the second gear teeth 1303a can be released from the restriction of the receiving portion 1304b, under the urging of the reset member 1305, the second transmission gear 1304 can be reset from the termination position as shown in Fig. 13(c) to the initial position as shown in Fig. 13(a) again, preferably, the reset member 1305 is a spring, more preferably, the spring is a torsion spring, of course, the reset member 1305 is not limited to the spring structure, but also can be elastic rubber, rubber rope, etc., which is not limited.

[0081] Next, the working process of the delay mechanism when the developing roller 1309 of the process cartridge 1300 is in contact with the photosensitive drum and the developing roller 1309 is separated from the photosensitive drum will be introduced in combination with Figs. 12-14, first, when the process cartridge 1300 is in the printing task, i.e. the state that the developing roller 1309 is in contact with the photosensitive drum, as shown in Fig. 12(a) and Fig. 13(c), the second gear teeth 1303a are located in the receiving portion 1304b of the second transmission gear 1304, and the second gear teeth 1303a are also kept spaced from the second transmission gear teeth 1304a, in this state, the reset member 1305 is elastically deformed and accumulates elastic force.

[0082] When the processing cartridge 1300 does not need to perform a printing task, the processing cartridge 1300 switches from a state of performing a printing task to a state of not needing to perform a printing task, the first coupling member 1320 stops rotating, the developing unit swings relative to the drum unit under the action of its own gravity in a direction away from the drum unit, the developing roller 1309 starts to separate from the photosensitive drum and gradually moves away, and then as shown in (b) of FIG. 12, the limiting portion 1353 and the limiting portion 1352c come into contact, the swing of the developing unit is inhibited, and the spacing distance between the developing roller 1309 and the photosensitive drum remains constant; when the developing unit starts to swing, the first transmission gear 1303 supported on the developing unit can gradually move away from the second transmission gear 1304 along with the swing of the developing unit, after the first transmission gear 1303 moves to a predetermined distance, the second gear tooth 1303a can be disengaged from the accommodating portion 1304b, so that the rotation limitation of the second transmission gear 1304 is released, the elastic force accumulated by the reset member 1305 is released and applied to the second transmission gear 1304, so that the second transmission gear 1304 is reset from the terminal position of (c) of FIG. 13 to the initial position of (a) of FIG. 13, so as to facilitate the second transmission gear 1304 to perform the next delayed driving action.

[0083] When the processing cartridge 1300 needs to perform a printing task again, the processing cartridge 1300 switches from a state of not performing a printing task to a state of needing to perform a printing task, the first coupling member 1320 starts to rotate, at this time, the developing unit swings relative to the drum unit under the torque of the first coupling member 1320 by a certain distance until the second gear teeth 1303a of the first transmission gear 1303 and the second transmission gear teeth 1304a of the second transmission gear 1304 are engaged, so that the position of the developing unit relative to the drum unit is limited and cannot continue to swing, at this time, the developing roller 1309 is still spaced from the photosensitive drum; as the first coupling member 1320 starts to rotate, the first transmission gear 1303 is driven to start to rotate, at this time, the second transmission gear teeth 1304a of the second transmission gear 1304 in contact with the second gear teeth 1303a of the first transmission gear 1303 are driven to rotate, the second transmission gear 1304 starts to rotate against the reset force of the reset member, the second transmission gear 1304 will be in an intermediate position as shown in Fig. 13(b) for a period of time, until the second transmission gear 1304 rotates to a position where the second transmission gear teeth 1304a are disengaged from the second gear teeth 1303a of the first transmission gear 1303, the second transmission gear 1304 will stop rotating, and finally at least part of the second gear teeth 1303a of the first transmission gear 1303 is accommodated in the accommodating portion 1304b of the second transmission gear 1304, at this time, the second transmission gear 1304 is in the terminal position as shown in Fig. 13(c), at this time, the position limitation of the developing unit is released, the developing unit swings relative to the drum unit under the rotating torque of the first coupling member 1320 against the gravity of the developing unit, so that the developing roller 1309 contacts the photosensitive drum again, so that the printing task can continue to be performed, that is, when the first coupling member 1320 starts to rotate, due to the limitation of the second gear teeth 1303a and the second transmission gear teeth 1304a, the torque of the first coupling member 1320 will not immediately make the developing unit swing to a position where the developing roller 1309 contacts the photosensitive drum, but after the second gear teeth 1303a and the second transmission gear teeth 1304a are disengaged, the developing unit loses the limitation and moves to a position where the developing roller 1309 contacts the photosensitive drum under the torque, therefore, the time delay mechanism provided in the processing cartridge 1300 can delay the driving of the developing unit to swing after the first coupling member 1320 starts to rotate, thereby solving the above technical problems.

[0084] Embodiment 4

[0085] As shown in Figs. 16-21, a process cartridge 1400 according to an embodiment of the present application is shown, which is the same as the process cartridges in the above-mentioned embodiments 2-3 in that the separation of the developing roller from the photosensitive drum is accomplished by the weight (i.e. gravity) of the developing unit itself, and the contact of the developing roller with the photosensitive drum is achieved by the torque of the rotating member in the developing unit, so the same structure and function will not be described again, and the differences will be described in detail below.

[0086] The process cartridge 1400 includes a support member 1421 provided at one end of the photosensitive drum 1404, which is used to connect and rotatably support the photosensitive drum 1404 on the housing. Preferably, the support member 1421 is configured as a second coupling member connected at one end of the photosensitive drum 1004, and the structure of the support member 1421 as a second coupling member will be described below. The second coupling member is at least partially exposed outside the process cartridge 1400 through the exposure hole 1452b provided on the first cover 1452, so as to receive the driving force from the image forming device to rotate, thereby driving the photosensitive drum 1004 to rotate. At the same time, at least a portion of the second coupling member is rotatably supported by the inner wall of the exposure hole 1452b, that is, the second coupling member can be used as a connecting member to rotatably support the photosensitive drum 1004 on the first cover 1452. Alternatively, the first coupling member 1421 can also be divided into at least two parts, i.e. a first part that can receive the driving force and a second part that can be connected at one end of the photosensitive drum 1404 and supported on the inner wall of the exposure hole 1452b, wherein the second part is used as the support member 1421 to rotatably support the photosensitive drum 1404. The first part and the second part are operatively connected so as to transmit the driving force, that is, the driving force received by the first part can still be transmitted to the photosensitive drum 1404. Alternatively, one end of the photosensitive drum 1404 is not provided with a second coupling member, and the photosensitive drum 1404 can be driven to rotate by the first coupling member 1421, that is, the first coupling member 1421 can simultaneously drive the developing roller 1401 and the photosensitive drum 1404 to rotate, wherein the support member 1421 only serves to support the photosensitive drum 1404 and no longer has the function of transmitting the driving force.

[0087] The drum unit 1429 of the processing cartridge 1400 further comprises a charging roller 1405 and a second force applying portion 1406 which can urge the charging roller 1405 towards the photosensitive drum 1404, the second force applying portion 1406 is preferably a spring; further, the support 1421 is in clearance fit with the exposure hole 1452b, the support 1421 is configured to be movable in the exposure hole 1452b in a direction crossing the first direction, which also makes the photosensitive drum 1404 movable in a non-rotating linear movement in the direction crossing the first direction, more specifically, the charging roller 1405 can press the photosensitive drum 1404 under the urging of the second force applying portion 1406, so that the photosensitive drum 1404 has a movement towards the direction close to the developing roller 1401, which helps to keep the developing roller 1401 of the photosensitive drum 1404 in close contact when the processing cartridge 1400 is performing a printing task, and improves the conveying effect of the developing roller 1401 conveying the developer onto the photosensitive drum 1404; further, in order to ensure the stability of the support of the photosensitive drum 1404, the exposure hole 1452b is preferably a non-circular hole, the center P1 of the first side 1461 of the exposure hole 1452b close to the developing roller 1401 and the center P2 of the second side 1462 of the exposure hole 1452b away from the developing roller 1401 are not concentric, P1 and P2 are apart from each other by K in the front-rear direction (the installation direction of the processing cartridge 1400), K is 0.1mm-3mm, preferably, K is 0.1mm-0.8mm, at this time, the photosensitive drum 1404 has a good offset distance, which can avoid the problem of unstable positioning of the photosensitive drum 1404 when the offset distance is too large, it should be noted that the shape of the exposure hole 1452b is not limited, which can be the above-mentioned non-circular structure, or a circular structure, or an irregularly shaped hole structure, as long as the support 1421 can support the photosensitive drum 1404 to be movable in the direction crossing the first direction; further, in order to improve the urging effect of the photosensitive drum 1404, the urging force direction on the photosensitive drum 1404 is as close as possible to the position where the photosensitive drum 1404 and the developing roller 1401 contact each other, which helps to concentrate the force and provide greater urging force, therefore, the processing cartridge 1400 of the embodiment further comprises a first force applying portion 1407, the first force applying portion 1407 is installed on the first cover 1452, one end of the first force applying portion 1407 abuts against the support 1421, so that the support 1421 can be urged towards the developing roller 1401, the first force applying portion 1407 is preferably a torsional spring or a compression spring, optionally, it can also be a sponge, rubber or an elastic protrusion or an elastic sheet which is integrally formed with the first cover 1452 or the second housing, which is not limited.

[0088] As can be seen from the above embodiments, the developing unit 1410 and the drum unit 1429 are operatively connected through the cooperation between the first positioning protrusion 1452b provided on the first cover 1452 and the first positioning hole 1459b provided on the gear cover 1459b, thus, in addition to the above structure, the process cartridge 1400 in the present embodiment also provides another structure, i.e., the first positioning protrusion 1452b and the first positioning hole 1459b also adopt clearance fit, thus enabling the developing unit 1410 to make non-rotational linear movement relative to the drum unit 1429 in a direction intersecting the first direction, and enabling the developing roller 1401 to be further biased towards the photosensitive drum 1404. It should be noted that the structural cooperation between the first positioning protrusion 1452b and the first positioning hole 1459b is substantially the same as the structural cooperation between the support 1421 and the exposure hole 1452b, and thus will not be described herein again.

[0089] The present embodiment provides a process cartridge 1400, which can further enable the developing roller 1401 to maintain close contact with the photosensitive drum 1404, thus improving the conveying effect of the developer and improving the printing quality.

[0090] Embodiment 5

[0091] As shown in FIGS. 22-25, a process cartridge 1500 in the present embodiment 5 is shown. The process cartridge 1500 is the same as the process cartridges in the above embodiments 2-4 in that the process cartridge 1500 also enables the developing roller to be separated from the photosensitive drum through the weight (i.e., gravity) of the developing unit itself, and enables the developing roller to be in contact with the photosensitive drum through the torque of the rotating component in the developing unit, thus, for the structure and function of this part, the present embodiment will not be described again. For the differences, the following will be described in detail.

[0092] In order to make the developing roller and the photosensitive drum keep close contact when the process cartridge 1400 performs a printing task, and improve the contact stability between the two, in addition to the structure in which the photosensitive drum is actively close to the developing roller in Embodiment 4, the structure in which the developing roller is further close to the photosensitive drum in the present embodiment can also be adopted. Specifically, the force applying part 1560 is arranged on the developing unit 1510 in the process cartridge 1500, so as to increase the swing torque of the developing unit, and the speed fluctuation of the developing unit 1510 can be inhibited, so that the contact between the developing roller and the photosensitive drum is more stable. One structure of the force applying part 1560 is that, as shown in FIGS. 22-23, the force applying part 1560 is configured as a sponge, rubber or friction member or the like arranged between the first coupling member 1520 and the bearing plate 1559 for rotatably supporting the housing of the first coupling member 1520, as long as the member can inhibit the rotation of the first coupling member 1520. Preferably, the force applying part 1560 is a ring-shaped sponge sleeved on the first coupling member 1520. Therefore, by arranging the member, the swing torque of the developing unit is increased, so that the contact force between the developing roller and the photosensitive drum is increased, and the contact stability between the two is improved.

[0093] Another structure of the force applying part 1560 is that, as shown in FIG. 24, a damping agent is arranged between the first coupling member 1520 and the bearing plate 1559 for rotatably supporting the housing of the first coupling member 1520. The damping agent can be a viscous damping agent, a viscoelastic damping agent, a friction damping agent or the like, which is not limited. Further, the damping agent is partially or fully enclosed in the first coupling member 1520, so as to avoid the damping agent from flowing out with the rotation of the first coupling member 1520.

[0094] Still another structure of the force applying part 1560 is that, as shown in FIG. 25, the force applying part 1560 is configured as an elastic member operatively connected between the developing unit 1510 and the drum unit 1520. The elastic force generated by the elastic member can be applied to the developing unit 1510 and the drum unit 1529, so that the developing roller and the photosensitive drum are close to each other. Preferably, the elastic member is a tension spring or a compression spring. It is worth mentioning that, since the separation of the developing roller and the photosensitive drum in the present embodiment still relies on the gravity of the developing unit 1510, the elastic member is configured such that the elastic force generated by the elastic member is smaller than the separation force of the developing unit 1510. Therefore, when the developing roller and the photosensitive drum need to be separated, the separation can be normally achieved. When the developing roller and the photosensitive drum need to be in contact, the torque generated by the rotating component in the developing unit 1510 is applied to the developing unit 1510, and the elastic force of the elastic member is also applied to the developing unit 1510. Under the combined action of the two, the developing roller and the photosensitive drum will keep stable contact.

Claims

1. A process cartridge having a left end and a right end opposed in a left-right direction, the process cartridge comprising: a drum unit including a second housing and a photosensitive drum rotatable about a second axis extending in the left-right direction; a developing unit including a first housing and a developing roller rotatable about a first axis extending in the left-right direction; a first coupling member disposed at the right end of the process cartridge in the left-right direction and receivable of an external force to drive the developing roller to rotate; a chip having a chip electrical contact surface, the chip electrical contact surface being arranged with the photosensitive drum in an up-down direction crossing the left-right direction, the process cartridge having an upper end and a lower end in the up-down direction, the chip electrical contact surface being located at the upper end of the process cartridge, the photosensitive drum being located at the lower end of the process cartridge; the developing unit being movably coupled to the drum unit and movable relative to the drum unit about: (a) a first attitude in which the developing roller is in contact with the photosensitive drum; and (b) a second attitude in which the developing roller is separated from the photosensitive drum; characterized in that, when the process cartridge is located in the first attitude and positioned such that the developing roller is located at the lower end of the process cartridge and the second axis is lower than the first axis, the developing unit is movable to the second attitude by its own weight.

2. The process cartridge according to claim 1, wherein, the first coupling member is rotatable about a third axis, the developing unit and the drum unit are movably coupled to each other by a coupling portion, the coupling portion being located above the third axis in the up-down direction.

3. The process cartridge of claim 1, wherein, the first coupling member is rotatable about a third axis, the developing unit and the drum unit are movably coupled to each other by a coupling portion, the first axis is located in front of the second axis in a front-rear direction crossing the up-down direction and the left-right direction, and the coupling portion is located in front of the third axis in the front-rear direction.

4. The process cartridge of claim 1, wherein, the developing unit and the drum unit are rotatably coupled to each other by a coupling portion, the coupling portion includes a coupling hole provided on the developing unit and a coupling protrusion provided on the drum unit, the coupling protrusion being insertable into the coupling hole.

5. The process cartridge of claim 1, wherein, the first coupling member is rotatable about a third axis, the developing unit is rotatable relative to the drum unit about a fourth axis, and a distance between the third axis and the fourth axis in a direction perpendicular to the left-right direction is greater than a distance between the third axis and the first axis.

6. The process cartridge of claim 1, wherein, the developing unit is rotatable relative to the drum unit about a fourth axis, and a distance between the fourth axis and the first axis in the up-down direction is Y, where 20 mm ≦ Y ≦ 45 mm.

7. The process cartridge of claim 1, wherein, the developing unit is rotatable relative to the drum unit about a fourth axis, and a distance between the fourth axis and the first axis in a front-rear direction crossing the left-right direction and the up-down direction is X, where 14 mm ≦ X ≦ 26 mm.

8. The process cartridge of claim 1, wherein, The second housing includes a first cover positioned at the right end of the process cartridge in the left-right direction, the first cover covering at least a portion of the first housing as viewed from the right end to the left end of the process cartridge, the first cover being provided with an exposure opening communicating with the outside of the process cartridge in a direction intersecting the left-right direction, at least a portion of the first coupling member being exposed outside the process cartridge through the exposure opening.

9. The process cartridge of claim 1, wherein, The second housing includes a first cover positioned at the right end of the process cartridge in the left-right direction, the first cover covering at least a portion of the first housing as viewed from the right end to the left end of the process cartridge, the developing unit being provided with a positioned portion, the drum unit being provided with a limiting portion, movement of the developing unit in a direction in which the developing roller is separated from the photosensitive drum being limited by the limiting portion in contact with the positioned portion when the process cartridge is in the second attitude, the developing unit being rotatable relative to the drum unit about a fourth axis, the fourth axis being located at a distance from the limiting portion greater than or equal to a distance of the fourth axis from the first axis in a direction perpendicular to the left-right direction.

10. The process cartridge of claim 9 wherein, The positioned portion is positioned at a lower end of the first coupling member in the up-down direction.

11. The process cartridge of claim 9 wherein, The process cartridge further includes a gear cover provided on the developing unit, the gear cover covering at least a portion of the first coupling member, the positioned portion being configured as a protrusion provided on the gear cover, the limiting portion being configured as a hole provided on the first cover.

12. The process cartridge of claim 1, wherein, The process cartridge further includes a support member provided at one end of the photosensitive drum in the left-right direction, the support member being configured to rotatably support the photosensitive drum on the second housing, the support member being configured to be movable relative to the second housing in a direction intersecting the left-right direction.

13. The process cartridge of claim 12, wherein, The process cartridge further includes an elastic member configured to apply a force to the support member so as to urge the support member to move in a direction approaching the developing roller in a direction intersecting the left-right direction.

14. The process cartridge of claim 1, wherein, The first coupling member includes a coupling protrusion and a coupling gear provided separately from each other, the coupling protrusion being configured to be movable relative to the coupling gear in a direction intersecting the left-right direction.

15. The process cartridge of claim 1, wherein, The process cartridge further includes a damping portion provided on the developing unit, the damping portion being configured to dampen rotation of the first coupling member.

16. The process cartridge of claim 15, wherein, The damping portion is a sponge, a rubber, or a damper.

17. The process cartridge of claim 1, wherein, The process cartridge further includes a time delay mechanism provided at one end of the process cartridge in the left-right direction, the time delay mechanism being configured to lengthen a time required for the developing unit to move from a position in which the developing roller is separated from the photosensitive drum to a position in which the developing roller is in contact with the photosensitive drum.

18. The process cartridge of claim 17, wherein, The time delay mechanism includes a transmission gear configured to move in response to rotation of the first coupling member to allow the developing unit to move from the second attitude to the first attitude.

19. The process cartridge of claim 18 wherein, The transmission gear includes a first transmission gear provided on the developing unit and a second transmission gear provided on the drum unit, and the driving force output from the first coupling member is sequentially transmitted to the first transmission gear and the second transmission gear.

20. The process cartridge of claim 19 wherein, The second transmission gear is configured as a cogwheel having a cogwheel tooth portion and a cogwheel toothless portion, the cogwheel tooth portion of the second transmission gear is engaged with the first transmission gear to be in a first position to receive the driving force to rotate when the developing unit is in the second posture, and the cogwheel toothless portion of the second transmission gear is opposite to the first transmission gear to be in a second position different from the first position when the developing unit is in the first posture.

21. The process cartridge of claim 20 wherein, The second transmission gear is rotatable along a fifth axis, and the second transmission gear is recessed in a direction perpendicular to the fifth axis to form a relief portion, at least a portion of the first transmission gear is accommodated in the relief portion when the developing unit is in the first posture.

22. The process cartridge of claim 21, wherein, The time delay mechanism further includes a reset member which can apply a force to the second transmission gear, so that the second transmission gear in the second position has a moving tendency to move to the first position.

Images