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 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.

An image forming apparatus includes an apparatus main body, a process cartridge, a scanner unit, and a toner cartridge. The process cartridge is detachably mounted on the apparatus main body. The process cartridge includes: a photosensitive drum configured to rotate about a rotational axis extending in a first direction; and a development unit configured to supply toner to the photosensitive drum. The toner cartridge is configured to store toner. At least part of the photosensitive drum, at least part of the scanner unit, and at least part of the toner cartridge are aligned in a second direction in this order. The second direction is perpendicular to both the first direction and to a vertical direction. The at least part of the photosensitive drum, the at least part of the scanner unit, and the at least part of the toner cartridge overlap one another as viewed from the second direction.

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.

An apparatus body of an image forming apparatus has a first guide portion having an inlet shape corresponding to an outer shape of an engagement portion provided in a cartridge when seen in an attachment direction of the cartridge to the apparatus body and guiding the engagement portion, a second guide portion for guiding a positioning target portion which is provided on the cartridge for positioning an attachment completion position of the cartridge with respect to the apparatus body, and a movable member being at a regulation position at which a guiding path of the positioning target portion by the second guide portion is blocked is immovable from the regulation position unless being pressed by the engagement portion.

A process cartridge includes a photoreceptor drum that is disposed in a main body frame, and a charging roller unit that includes a charging roller disposed in parallel with an axial direction of the photoreceptor drum and is a separate body from the main body frame. The charging roller unit includes a protrusion. The main body frame includes a guide into which the protrusion is inserted in a state where the charging roller is spaced apart from the photoreceptor drum, and a positioner that is continuously formed at an end part of the guide on an opposite side to an insertion side of the protrusion and positions the charging roller at a position where the charging roller is in contact with the photoreceptor drum.

An image-forming apparatus includes: a main casing; a drawer movable in a first direction relative to the main casing; a process cartridge detachably mountable on the drawer; and a toner cartridge. The drawer includes a first drawer side plate and a second drawer side plate spaced apart from each other in a second direction crossing the first direction. The process cartridge includes: a photosensitive drum rotatable about an axis extending in the second direction when the process cartridge is mounted on the drawer; and a developing device for supplying toner to the photosensitive drum. When the process cartridge is mounted on the drawer and the toner cartridge is attached to the process cartridge, the toner cartridge has a length in the second direction greater than a distance in the second direction between the first drawer side plate and the second drawer side plate.

An apparatus body of an image forming apparatus has a first guide portion having an inlet shape corresponding to an outer shape of an engagement portion provided in a cartridge when seen in an attachment direction of the cartridge to the apparatus body and guiding the engagement portion, a second guide portion for guiding a positioning target portion which is provided on the cartridge for positioning an attachment completion position of the cartridge with respect to the apparatus body, and a movable member being at a regulation position at which a guiding path of the positioning target portion by the second guide portion is blocked is immovable from the regulation position unless being pressed by the engagement portion.

An image-forming apparatus includes: a main casing; a drawer movable in a first direction relative to the main casing; a process cartridge detachably mountable on the drawer; and a toner cartridge. The drawer includes a first drawer side plate and a second drawer side plate spaced apart from each other in a second direction crossing the first direction. The process cartridge includes: a photosensitive drum rotatable about an axis extending in the second direction when the process cartridge is mounted on the drawer; and a developing device for supplying toner to the photosensitive drum. When the process cartridge is mounted on the drawer and the toner cartridge is attached to the process cartridge, the toner cartridge has a length in the second direction greater than a distance in the second direction between the first drawer side plate and the second drawer side plate.

An image forming apparatus includes a port to permit a imaging unit to be installed. A solid head unit has a base, a lifting mechanism, a print head, and a first guide. The lifting mechanism moves the print head up and down. The first guide includes a first guide rail facing the print head that limits the movement of the print head to a first range when the print head and a second, greater range when the print head is raised. The imaging unit includes a photoconductive drum in a drum case that includes a projection facing the solid head unit. The projection is configured to insert into a hole in the print head when the print head is raised.