A sheet processing apparatus has a main body with an insertion slot for a sheet cassette. The sheet cassette has a moveable pin member. A housing in the main body includes a lever partially rotatable about a first axis. The lever has a pin engagement portion at an end of the lever that rotates about a second axis and has an engagement groove into which the pin member can be inserted from a first pin engagement position and a second pin engagement position when the lever has rotated about the first axis. An elastic member applies a force to the lever to rotate the lever toward the insertion direction of the cassette. The housing includes a chassis having a guide groove extending along the insertion direction. The guide groove includes an inclining portion that is inclined with respect to the insertion direction.

An image-forming device includes a main casing, a belt accommodated in the main casing, developing units arranged along the belt, a drawer configured to detachably support the developing units, the drawer configured to move to a position inside the main casing and to a position outside the main casing, and the drawer having a leading end and a trailing end in a pulling direction from the inside position to the outside position; and a guide configured to guide the drawer and to move between a first position and a second position when the drawer is at the inside position, the second position being farther from the belt than the first position from the belt. When the guide is at the second position, the guide is configured to be tilted downward relative to a horizontal direction such that the leading end is lower than the trailing end.

An image forming apparatus includes an image bearing member, a frame member including a support surface and made of metal, an exposure unit disposed such that an emission direction in which the light is emitted to the image bearing member is inclined with respect to the support surface, a support member made of metal and configured to support the exposure unit that is in an inclined posture with respect to the support surface, and a positioning member made of resin and configured to be in contact with the exposure unit and position the exposure unit. The support surface of the frame member is in contact with at least one of the support member or the positioning member, and wherein the exposure unit is configured to be attached to the frame member via the support member and the positioning member.

A drum unit includes: a frame; a first photosensitive drum; a second photosensitive drum; a charger; and a storage medium. The frame includes: a first frame plate; a second frame plate spaced apart from the first frame plate in a first direction; a third frame plate connecting one end of the first frame plate to one end of the second frame plate; and a fourth frame plate connecting another end of the first frame plate to another end of the second frame plate. The first photosensitive drum and the second photosensitive drum are rotatably supported by the frame. The second photosensitive drum is spaced apart from the first photosensitive drum and positioned closer to the third frame plate than the first photosensitive drum to the third frame plate in a second direction. The storage medium has an electrical contact surface positioned at an outer surface of the third frame plate.

A first cartridge support is configured to support a drum cartridge. The first cartridge support is configured to move in a first direction between a first position at which the drum cartridge is mounted on a housing and a second position at which the drum cartridge is detachable. A second cartridge support is configured to support a development cartridge. The second cartridge support is configured to move in the first direction between a third position at which the development cartridge is mounted on the drum cartridge and a fourth position at which the development cartridge is detachable. In a state where the second cartridge support is located at the third position, the second cartridge support is located between the first cartridge support located at the first position and a cover located at a closed position with respect to the first direction.

An image forming apparatus, includes a body housing, a drawer movable between an accommodated position and a drawn position, a drum cartridge including a photoconductor drum, a developing cartridge including a developing roller, and a belt located above the photoconductor drum, and the drawer is located at the accommodated position. The drum cartridge includes a moving member movable, with respect to the photoconductor drum, between (i) a first position which is a position at which the moving member is not opposed to the developing cartridge mounted on the drum cartridge and is opposed to a circumferential surface of the photoconductor drum and (ii) a second position which is a position at which the moving member is not opposed to the circumferential surface of the photoconductor drum and is opposed to the developing cartridge mounted on the drum cartridge.

An image forming apparatus includes a body casing, a pressing member, a process cartridge, and a drawer. The body casing includes a positioning member. The pressing member is disposed inside the body casing. The process cartridge includes a photosensitive drum. The drawer is configured to support the process cartridge and to move, in a sliding direction orthogonal to an axis direction of the photosensitive drum, between an inside position that is a position inside the body casing and an outside position that is a position outside the body casing. The process cartridge includes an engagement portion and a spring. The engagement portion is configured to be positioned by the positioning member. The spring is configured to be pressed by the pressing member such that the engagement portion is pressed toward the positioning member.

A unit attachment-detachment mechanism includes a unit and a pair of guide rails. The pair of guide rails slidably supports a pair of side faces of the unit. The side faces respectively have formed thereon engagement projections that engage with the guide rails. The pair of guide rails has formed therein at least a pair of inclined portions. The pair of inclined portions is formed asymmetrically with each other in the unit width direction perpendicular to the attachment-detachment direction.

An image forming apparatus includes an apparatus main body, a cartridge including a supported portion, a moving member configured to move to the apparatus main body and thereby move the cartridge, the moving member moving to the apparatus main body so as to be in an external position and an internal position, a main body side positioning portion provided on the apparatus main body and configured to, when the moving member is in the internal position, support the supported portion, and an upward inclination portion provided on the apparatus main body and inclined upwardly from a movement direction in which the moving member moves from the external position to the internal position. The upward inclination portion causes the cartridge to move upward with respect to the moving member in a process in which the moving member moves from the external position to the internal position.

An image forming device, including: a housing; a drawer movable between an inside position at which the drawer is located inside the housing and an outside position at which the drawer is located outside the housing; a drum cartridge including a photoconductive drum and a developer roller and mountable on the drawer; a toner cartridge storing toner to be supplied to the developer roller and mountable on the drawer, wherein the drawer includes a first guide that guides the toner cartridge in mounting the toner cartridge on the drawer, and wherein the drum cartridge includes a second guide connected to the first guide in a state in which the drum cartridge is mounted on the drawer, the second guide being configured to guide the toner cartridge in mounting the toner cartridge on the drawer in the state in which the drum cartridge is mounted on the drawer.