A drum unit, to which a developer cartridge with a developer roller and a protrusion protruding in an axial direction of the developer roller is attachable, is provided. The drum unit includes a casing, a photosensitive drum to contact the developer roller, a first guide arranged to confront the protrusion along a direction orthogonal to the axial direction when the developer cartridge is attached to the casing to guide the protrusion, a second guide movable between a first position and a second position to guide the protrusion and arranged to confront the protrusion along the orthogonal direction when the developer cartridge is attached to the casing, and an urging member to urge the second guide in a direction from the first position toward the second position. The second guide includes a contact part to contact the first guide when the second guide is in the second position.

An image forming apparatus, including a photosensitive drum, a developer cartridge with a developer roller and a protrusion, a casing, a separator member to move the developer cartridge between a contact position and a separate position, and a first guide to guide the protrusion, is provided. The first guide confronts the protrusion along a direction orthogonal to an axial direction of the developer roller when the developer cartridge is in the contact position. The first guide includes a first guiding surface and a first inclined surface. The first guiding surface extends in parallel with a line connecting a center of a rotation axis of the developer roller with a center of a rotation axis of the photosensitive drum. The first inclined surface inclines with respect to the first guiding surface. The protrusion contacts the first inclined surface when the separator member moves the developer cartridge toward the separate position.

An electrical connecting member electrically connects between two conductive members comprising. The electrical connecting member includes a coil spring part formed by winding a wire around a coil axis. The electrical connecting member comes into contact with one of the conductive members with elastic force in a circumferential direction around the coil axis and comes in contact with the other of the conductive members with elastic force in an axial direction of the coil axis so that the conductive members are electrically connected.

An image forming apparatus includes an apparatus main body and a unit. The apparatus main body includes a positioning hole extending in a first direction intersecting with a mounting direction of the unit, and a pair of first inner edges extending in the first direction. The unit includes a sheet metal member and a positioning unit formed on a distal end side of the sheet metal member in the mounting direction. The sheet metal member includes a first surface extending along the mounting direction and a second surface located on an opposite side from the first surface. The positioning unit includes a projection piece inserted into the positioning hole, and a protrusion. The protrusion is formed by deforming the sheet metal member such that the second surface of the projection piece is partially perpendicular to the mounting direction and projects to a second direction perpendicular to the first direction.

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 fourth frame plate.

A packing member for packing a cartridge for an image forming apparatus, the packing member includes a frame portion having a recess for accommodating the cartridge; a closing member portion for openably closing the recess; a hinge portion for movably connecting the closing member portion relative to the frame portion to open and close the recess; a connecting portion connecting the frame portion and the closing member portion to close the recess; and the closing member portion being provided with a separating portion removable from the closing member portion while leaving the connecting portion on the frame portion.

In an image forming apparatus, a belt unit, a process cartridge, and an exposure unit are arranged in this order in a first direction such that the belt unit is positioned at an upstream side of the process cartridge in the first direction and the exposure unit is positioned at a downstream side of the process cartridge in the first direction. The photosensitive drum is engaged to a positioning member from an upstream side of the positioning member in the first direction. A pressing member presses the process cartridge from the upstream side toward the downstream side of the process cartridge in the first direction. The pressing member moves between a first position, at which the pressing member presses the process cartridge, and a second position, at which pressing of the pressing member to the process cartridge is released.

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 apparatus includes: a housing; a drawer; and first and second process cartridges attachable to the drawer. The first process cartridge includes a first drum cartridge including a first photosensitive drum and a first developing cartridge including a first developing roller. When attached to the first drum cartridge, the first developing cartridge is movable between a first position where the first developing cartridge is detachable from the first drum cartridge and a second position where the first developing cartridge is not detachable from the first drum cartridge. In a state where the first and second process cartridges are attached to the drawer at positions adjacent to each other, the first developing cartridge comes into contact with the second process cartridge during movement of the first developing cartridge from the second position to the first position before the first developing cartridge reaches the first position.

A developing cartridge including a casing, a developing roller, a developing roller gear, a gear cover, a first boss, and a pressure receiving surface. The developing roller is positioned closer to a first end portion of the casing than to a second end portion of the casing in a first direction. The first boss extends in a second direction and is movable together with the casing. The first boss is positioned away from the developing roller in the first direction by a first distance and also positioned away from the developing roller in a third direction. The pressure receiving surface is positioned further from the developing roller than the first boss is from the developing roller in the third direction. The pressure receiving surface is positioned away from the developing roller by the first distance or by a second distance shorter than the first distance.