A developing device is detachably supported by an image forming apparatus. The developing device includes a housing that can store developer inside the housing, at least one rotating member rotatably provided for the housing, a first support shaft composed of a conductive member and disposed at an axial end of the rotating member, and a support member including a first bearing portion that supports the first support shaft and constituting a side face of the housing in an axial direction of the rotating member. The first bearing portion includes a first guide portion. The first guide portion protrudes outward from an outer surface of the support member and configured to be guided to an installation position of the developing device during installation of the developing device in the image forming apparatus.

A process cartridge is provided. The process cartridge is detachably mounted in an image formation apparatus configured with a power output unit that is swingable, an outer circumference of the power output unit contains a recessed portion. The process cartridge includes: a power receiving unit, comprising a wheel hub and a power receiving member connected with the wheel hub, the power receiving member being engaged with the power output unit to receive a driving force; where the wheel hub comprises a hollow cylinder portion accommodating the power output unit; where the power receiving member includes a fixing protrusion, the fixing protrusion is engaged with the recessed portion of the power output unit to receive the driving force; where the power receiving unit further comprises a bias part, the bias part applies a bias force to drive the power output unit to move to engage with the fixing protrusion.

A drum cartridge includes: a photosensitive drum rotatable about a drum axis extending in an axis direction; a drum cleaner including a cleaning member cleaning a circumferential surface of the photosensitive drum, and a cleaning housing accommodating transfer residual toner removed from the circumferential surface of the photosensitive drum by the cleaning member; a first drum side plate supporting a first end portion of the photosensitive drum; a second drum side plate located distant from the first drum side plate in the axis direction and supporting a second end portion of the photosensitive drum; a pipe located between the first drum side plate and the second drum side plate in the axis direction and extending in the axis direction; and a conveyor device conveying the transfer residual toner from the cleaning housing to the pipe.

An image forming apparatus includes: a forming part that forms an image on a recording medium; a fixing part that fixes the image formed on the recording medium; a revolving part having a revolving member stretched over multiple rotary members, the revolving member revolving between the forming part and the fixing part to transport the recording medium from the forming part to the fixing part; a feed part that feeds the recording medium to the forming part; a discharge part that discharges the recording medium to which the image has been fixed in the fixing part; a branch part that is provided so as to be split from the discharge part and along which the recording medium, to one side of which the image has been fixed, is transported to the feed part after switching the leading end and the trailing end of the recording medium; a first housing accommodating the forming part, the fixing part, and the revolving part; and a second housing connected to the first housing and accommodating the feed part, the discharge part, and the branch part.

An image forming apparatus includes: a rotatable image carrier on an outer circumferential surface of which an image is to be formed and that is movable in a rotation axis direction between an image forming position and a maintenance position; a light-emitting unit including a base member extending in the rotation axis direction of the image carrier, and plural light-emitting devices provided on the base member and configured to apply light to the outer circumferential surface of the image carrier, the light-emitting unit being configured to move together with the image carrier in the rotation axis direction; and a supporting unit configured to move together with the image carrier in the rotation axis direction and to support the light-emitting unit when the image carrier and the light-emitting unit are at the maintenance position and the light-emitting unit is disabled from being positioned with respect to the image carrier.

An exposure device includes: at least one light emitter that includes a substrate and a light-emitting device disposed on the substrate; and a position adjuster that includes a contact member having an outer periphery in contact with the substrate, a support member that rotatably supports the contact member, and at least one mover that is in contact with the support member to move the support member in a light emission direction of the light emitter.

An image forming apparatus includes a first image forming unit including a rotatable first image carrier and a first light-emitting unit, the first light-emitting unit including a first base member and plural first light-emitting devices, the first base member extending in an axial direction of the first image carrier, the plural first light-emitting devices being provided on the first base member and being configured to apply light to an outer circumferential surface of the first image carrier; and a second image forming unit including a rotatable second image carrier and a second light-emitting unit, the second light-emitting unit including a second base member and plural second light-emitting devices, the second base member extending in an axial direction of the second image carrier, the plural second light-emitting devices being provided on the second base member and being configured to apply light to an outer circumferential surface of the second image carrier. A direction of detaching and attaching of the first light-emitting unit from and to the first image forming unit and a direction of detaching and attaching of the second light-emitting unit from and to the second image forming unit are different from each other.

An image forming apparatus includes an image bearing member, an apparatus body including a transfer member movable between a first position and a second position, an opening/closing member. The apparatus body includes a movement mechanism configured to move the transfer member in accordance with a movement of the opening/closing member. The movement mechanism includes a first movable member and a second movable member. The first movable member is configured to move a first end portion of the transfer member from the first position to the second position. The second movable member is configured to move a second end portion of the transfer member from the first position to the second position.

An image forming apparatus including a main body casing, a drum cartridge and a developing cartridge. The main body casing has an opening and a slot extending in from the opening toward an inside of the main body casing along a first direction. The drum cartridge and the developing cartridge are arranged in a second direction intersecting the first direction in a state where the drum cartridge and the developing cartridge are attached to the slot. The main body casing includes a drum guide groove configured to guide movement of the drum cartridge. The drum cartridge includes a drum protrusion configured to be engaged with the drum guide groove. A width of the drum guide groove in the second direction is decreased toward the inside of the main body casing from the opening.

An image forming apparatus includes a storage portion, a cover member, a locking mechanism, an unlocking portion, and a contact portion. The storage portion conveys developer stored therein in a conveying direction parallel to a rotation axis by being rotated around the rotation axis parallel to a horizontal plane in a first direction. The cover member opens and closes an insertion hole portion, into which the storage portion is inserted, in a side face of the apparatus body. The locking mechanism imposes a restriction on a state change of the cover member from a closed state to an open state. The unlocking portion removes the restriction on the state change imposed by the locking mechanism as a lever portion swings in a second direction opposite the first direction. The contact portion includes a curved surface and rotates integrally with the storage portion to come into contact with the lever portion.