Provided is a process cartridge where a developing unit includes a coupling member that receives driving force, a driving transmission member that transmits the driving force from the coupling member to a driving roller, and a support member that rotatably supports the coupling member and is movable with respect to a developing frame in a direction intersecting with a rotational axis of the developing roller. The developing frame and the driving transmission member are configured to be movable with respect to a drum frame of a drum unit in the direction intersecting the rotational axis. In this process cartridge, an urging member that engages with both the support member and the drum frame is included such that an urging force is applied in a direction in which a positioned portion of the support member and a positioning portion of the drum frame contact each other.

An image forming apparatus, having a casing, a drum unit including first and second lateral walls and first and second photosensitive drums, first and second cartridges supported by the drum unit, first and second operable members, is provided. The first operable member and the second operable member press the first developing cartridge and the second developing cartridge, respectively, in a direction from the first lateral wall toward the second lateral wall to move the first and second developing rollers from the respective contacting positions to respective separated positions. The casing includes a restrictive portion. When the drum unit is attached to the casing, the restrictive portion restricts movement of the drum unit causable by at least one of a pressing action of the first operable member to press the first developing cartridge and a pressing action of the second operable member to press the second developing cartridge.

A process cartridge includes a frame and a photosensitive drum supported by the frame, with the photosensitive drum being rotatable about an axis thereof. A coupling is operatively connected to the photosensitive drum such that a driving force can be transferred from the coupling to the photosensitive drum. A developing roller is supported by the frame, with the developing roller being rotatable about an axis thereof. A gear is positioned at a side of the process cartridge, with the gear being rotatable about an axis thereof. The gear has a plurality of teeth, with at least some of the teeth being exposed teeth that are uncovered by the frame and exposed to outside of the process cartridge, and with a tip of at least one of the exposed teeth facing the axis of the photosensitive drum. As measured in the axial direction of the photosensitive drum, the teeth of the gear are shorter than the projection of the coupling.

A developing cartridge includes a housing, a developing roller, a shaft, a first cam, and an elastic member. The housing has a first outer surface at one end portion of the housing in a first direction. The developing roller is rotatable about a first axis extending in the first direction. The shaft is along a second axis extending in the first direction. The shaft is movable in the first direction relative to both the housing and the developing roller. The first cam is at one end portion of the shaft in the first direction. The first cam is movable in the first direction together with the shaft. The elastic member is positioned outward of the shaft in a radial direction of the shaft. The elastic member is positioned between the first outer surface and the first cam in the first direction.

An image forming apparatus includes a photoelectric conversion portion, a housing, a housing support portion, and a posture adjustment portion. The photoelectric conversion portion receives light reflected by a document sheet placed on a document sheet mounting surface and outputs an electric signal based on the light. The housing has a box shape with an open top and forms a housing space for housing the photoelectric conversion portion on a lower side of the document sheet mounting surface. The housing support portion supports a bottom portion of the housing. The posture adjustment portion includes an operation portion provided outside the housing, and adjusts a posture of the photoelectric conversion portion in accordance with an operation on the operation portion.

A drive device that drives a detachable unit detachably attached to an image forming apparatus includes a drive coupling, a rotary shaft, a relay member, a contact member, and a compression spring. The drive coupling contacts and separate from a driven coupling of the detachable unit along with movement of the detachable unit. The relay member transmits rotation force of the rotary shaft to the drive coupling to rotate together. The compression spring has an axial end contacting the contact member disposed away from the driven coupling from the relay member and another axial end contacting the relay member. The drive coupling includes an outer circumferential restrictor restricts radial movement of the compression spring. The relay member includes an inner circumferential restrictor restricts radial movement of the compression spring.

A process cartridge including: a photosensitive member cartridge including a photosensitive member; and a developing cartridge including a developer carrier. The developing cartridge further includes: an inputting portion; a first cover; and a second cover. The first cover has a first engagement portion configured to move the developer carrier away from the photosensitive member. The first engagement portion is positioned between an axis of the developer carrier extending in an axial direction and an axis of the inputting portion extending in the axial direction, when projected in the axial direction. The second cover has a second engagement portion configured to move the developer carrier away from the photosensitive member. The second engagement portion is positioned between the axis of the developer carrier and the axis of the inputting portion, when projected in the axial direction.

A cartridge includes a photosensitive drum supported by a frame, a coupling positioned at an end of the photosensitive drum, with the coupling being configured to receive a driving force for rotating the photosensitive drum. A lever is movably supported by a part of the frame at a position that is adjacent to the end of the photosensitive drum, with the lever being movable between a first position and a second position. As viewed along the axis of the photosensitive drum, an end of the lever is a first distance from the axis of the photosensitive drum when the lever is in the first position, and the end of the lever is a second distance from the axis of the photosensitive drum when the lever is in the second position, with the second distance being greater than the first distance.

In a cartridge, a housing has a developer accommodating portion and includes a first side wall and a second side wall. A coupling member is disposed at a position opposite to the developer accommodating portion with respect to the first side wall. A detection body is disposed at a position opposite to the developer accommodating portion with respect to the second side wall. A first driving force transmission member is positioned at the same side with the coupling member with respect to the first side wall, and transmits driving force from the coupling member to a rotating member. A second driving force transmission member is positioned at the same side with the detection body with respect to the second side wall, and transmits driving force from the rotating member to the detection body.

A photosensitive member unit includes a photosensitive member, a transfer roller, a mounting portion capable of mounting a development unit including a development roller, a first gear and a second gear each provided at one end of the photosensitive member in an axial direction of the photosensitive member, and a third gear provided at one end of the transfer roller in an axial direction of the photosensitive member and configured to engage with the second gear. The first gear, the second gear, and the third gear are helical gears. A direction in which helical teeth of the first gear are inclined is opposite to a direction in which helical teeth of the second gear are inclined, and the direction in which the helical teeth of the first gear are inclined matches a direction in which helical teeth of the third gear are inclined.