An image-forming apparatus includes: a photosensitive drum, a motor, and a drum gear train configured to transmit a driving force from the motor to the photosensitive drum. The drum gear train includes a first gear, a second gear and a first clutch. The first gear is rotatable about a first axis upon receipt of the driving force. The second gear is rotatable about the first axis and configured to receive the driving force from the first gear and to transmit the driving force to the photosensitive drum. The first clutch is switchable between a first transmission state where the driving force is transmitted from the first gear to the second gear and a first transmission cutoff state where the transmission of the driving force from the first gear to the second gear is cut off.

A process cartridge comprises a photosensitive drum and a developing roller. A coupling member is provided adjacent to one axial end of the developing roller. The coupling member includes a driven portion, and an intermediary portion configured and positioned to engage with the driven portion. The intermediary portion is also configured to be movable relative to the driven portion in a direction crossing the axis of the developing roller while maintaining engagement with the driven portion. The coupling member further includes a driving portion configured and positioned to receive a driving force for rotating the developing roller. The driving portion is also configured to engage with the intermediary portion, and to be movable relative to the intermediary portion in a direction crossing the axis of the developing roller while maintaining engagement with the intermediary portion.

To provide a process cartridge, a drum unit capable of receiving a driving force from the main assembly, and an image forming apparatus including the process cartridge. A cartridge is provided with a movable member having a driving force receiving portion. The movable member moves between an advanced position and a retracted position.

In one example in accordance with the present disclosure, a developer unit seal is described. The developer unit seal includes an endcap. The endcap has an opening to receive a dynamic seal for a roller, an inlet to receive print fluid, and a channel embedded in a surface of the endcap. The channel connects the inlet with the opening to direct print fluid to the opening. The developer unit seal also includes a sealing member to cover the channel.

According to one embodiment, a sheet conveying device includes a roller, a motor, a clutch, and a torque generator. The roller conveys a sheet. The motor is a driving source. The clutch connects or disconnects drive of the motor with respect to the roller. The torque generator applies a torque to the roller.

A gear includes a gear body to be attached to a distal end of a driving shaft in an axial direction of the driving shaft and including teeth each extending obliquely with respect to the axial direction, and a stopping portion included in the gear body and configured in such a manner as to allow the driving shaft to which the gear body is attached to move in a circumferential direction. When the driving shaft moves in the circumferential direction, the stopping portion is enabled to stop the gear body from moving in the axial direction, the stopping portion stopping the gear body by coming into contact with a portion of the driving shaft.

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.

An image forming apparatus includes a drive roller configured to be rotated by a drive source, a first rotation member configured to be driven to rotate by the drive roller, and a second rotation member configured to be driven to rotate by the drive roller. The drive roller, the first rotation member, and the second rotation member are configured to convey a sheet in a state where the sheet is present at a first nip portion and a second nip portion at the same time.

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.