A process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus, includes a rotatable photosensitive drum; a rotatable developing roller configured to develop image formed on the drum, the developing roller being capable of contacting to and spacing from the drum; an urging force receiving portion configured to receive, from a main assembly side urging member, an urging force for spacing the developing roller from the drum; a cartridge side drive transmission member capable of the coupling with a main assembly side drive transmission member and configured to receive, from the main assembly side drive transmission member, a rotational force for rotating the developing roller; and a decoupling member capable of urging the cartridge side drive transmission member by the urging force received by the urging force receiving portion to decouple the cartridge side drive transmission member from the main assembly side drive transmission member.

A photosensitive member unit detachably mountable to a main assembly of an image forming apparatus, the image forming apparatus including a first main assembly side helical gear portion and a second main assembly side helical gear portion which are coaxially rotatable, the photosensitive member unit includes a photosensitive member rotatable about a rotational axis thereof; a first unit side helical gear portion for meshing engagement with the first main assembly side helical gear portion; and a second unit side helical gear portion for meshing engagement with the second main assembly side helical gear portion, wherein a twisting direction of a tooth of the second unit side helical gear portion is the same as the twisting direction of a tooth of first unit side helical gear portion, wherein a helix angle of the tooth of the second unit side helical gear portion is larger than a helix angle of the tooth of the first unit side helical gear portion, and wherein the first unit side helical gear portion and the second unit side helical gear portion are rotatable in a state in which the first unit side helical gear portion is in meshing engagement with the first main assembly side helical gear portion, and the second unit side helical gear portion is in meshing engagement with the second main assembly side helical gear portion.

Examples of a print particle replenishment device are described herein. Some examples of the print particle replenishment device may include an interfacing portion. Some examples of the interfacing portion may include a ramp to actuate a hinging door. In some examples, the hinging door may be on a host device receptacle.

An example image forming apparatus includes a frame, a first shaft supported by the frame, and a first coupler. The first coupler includes a body coupled to one end of the first shaft and a first protrusion protruding from the body in an axial direction of the first shaft, the first protrusion having a first surface and a second protrusion protruding from the first surface. The second protrusion is to lock with a groove to mount a cartridge on the frame, the first shaft is to provide a rotational force in a first rotational direction to rotate the second protrusion of the first coupler and to insert the second protrusion into the groove to lock with the cartridge, and the first surface of the first protrusion of the first coupler is to contact a second surface to transmit the rotational force to the second coupler in the first rotational direction.

An image forming apparatus includes a toner container, a storage part, a cover and an opening/closing mechanism. The toner container includes a shutter. The cover is movable between a closed position for closing the storage part and an opened position for opening the storage part. The opening/closing mechanism closes a supply port by rotating the shutter in accordance with an opening operation for moving the cover to the opened position and opens the supply port by rotating the shutter in accordance with a closing operation for moving the cover to the closed position, in a state where the toner container is attached to the storage part. The toner container includes an interference portion which interferes with the opening/closing mechanism to prevent the toner container from being attached to the storage part in a case where the cover is not moved to the opened position normally.

An image forming apparatus, having a photosensitive drum assembly, an exposure head, and a bearing, is provided. The photosensitive drum assembly includes a photosensitive drum and a flange disposed at an end of the photosensitive drum in an axial direction of an axis of the photosensitive drum. The flange contacts an inner surface of the photosensitive drum. The exposure head includes a plurality of light emitters aligned along the axial direction of the photosensitive drum, a lens array focusing light from the light emitters on the photosensitive drum, and a head frame to support the light emitters and the lens array. The bearing has a first contact face to contact the exposure head to define a distance between the lens array and the photosensitive drum along a direction of an optical axis of the light.

An image forming apparatus includes a paper feed device and an image forming apparatus main body including a paper feed cassette removable from the image forming apparatus main body and including an image forming unit. The paper feed cassette stores a recording material, and the image forming unit forms an image on the recording material. The paper feed device allows the image forming apparatus main body to be stacked on the paper feed device below the paper feed cassette. The paper feed device is provided with a coupling section. In a space formed in a case where the paper feed cassette is removed from the image forming apparatus main body, the coupling section is fixed to the image forming apparatus main body by a fixing unit to couple the image forming apparatus main body and the paper feed device together.

An image forming apparatus includes an image bearing member, a developing device including a developer container and a developer carrying member, a mounting portion, a moving mechanism, a cover member, a wall member, a first seal member, a second seal member, and a fan. The developing device is in a separated position, neither the first seal member or the second seal member contacts the wall member. When the developing device is in a developing position, both the first seal member and the second seal member contact the wall member. When the developing device is in the developing position, a space for permitting passing of an airflow by the fan is formed along a mounting direction by the cover member, the wall member, the first seal member, and the second seal member.

A developer supply container is detachably mountable to a developer receiving apparatus, the developer receiving apparatus including a developer receiving portion provided with a receiving port for receiving a developer and including a portion-to-be-engaged of displacing integrally with the developer receiving portion. The developer supply container includes a discharging portion provided with a shutter opening for discharging the developer accommodated in the developer accommodating portion, and an engaging portion. The engaging portion engages with the portion-to-be-engaged with a mounting operation of the developer supply container to displace the developer receiving portion so as to bring the receiving opening into fluid communication with the shutter opening. The engaging portion includes a curved portion having an angle relative to a mounting direction of the developer supply container, the angle decreasing with approach toward an upstream side in the mounting direction.

A detachable container includes: a container body configured to be detachably attached to a receiving portion of an apparatus housing; a joining unit provided on the container body, the joining unit being configured to be rotatably joined with a joined unit provided on the apparatus housing; an operation unit having a rotation center coaxial with the joining unit, the operation unit being configured to perform a rotational operation for the joining unit; and a restraint unit provided coaxially with the rotation center of the operation unit, the restraint unit being configured to, when the container body is attached to the receiving portion of the apparatus housing, allow a rotation of the operation unit, and when the container body is not attached, to restrain the rotation of the operation unit.