In an image forming apparatus, a process frame is movable into and out of a main casing in a first direction. The process frame includes a first wall and a second wall spaced apart from the first wall in a second direction. A first cartridge is detachably mountable to the process frame in a third direction crossing the second direction. A first electrode protrudes from an outer surface of the first cartridge outwardly in the second direction. In a state where the first cartridge is mounted to the process frame, the first cartridge is positioned between the first wall and second wall of the process frame in the second direction and a portion of the first wall aligns with the first electrode in the third direction such that the portion of the first wall is overlapped with the first electrode as viewed in the third direction.

An image forming apparatus includes: a photosensitive drum; a developing roller; a separation mechanism for moving the developing roller between a contacting position contacting the photosensitive drum and a separated position separated from the photosensitive drum; a first tray; a first sheet feed mechanism for feeding a sheet from the first tray toward the photosensitive drum; a first sheet sensor for detecting passage of the sheet at a prescribed position; and a controller. The controller of the image forming apparatus is configured to perform: when a printing operation is performed onto the sheet ted from the first tray, feeding the sheet in the first tray to the prescribed position and maintain the sheet; moving, on or after the first sheet sensor detects the sheet, the developing roller to the contacting position.

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.

An image forming apparatus includes a main body housing, a drawer, a drum cartridge, and a toner cartridge. The drawer includes a waste toner conveying pipe and a lock member. In a state where the toner cartridge is mounted on the drum cartridge, the drum cartridge is mounted on the drawer, the drawer is located at a drawn-out position, and the lock member is located at a lock position, the toner cartridge is detachable from the drum cartridge.

An image forming apparatus is provided, including a housing; a drum cartridge; a developing cartridge; a drawer movable between an inner position and an outer position; and a lock member provided on the drawer and movable between a lock position at which the lock member locks the drum cartridge to the drawer, and a release position at which a lock between the drum cartridge and the drawer is released. The lock member includes an operation portion for moving the lock member between the lock position and the release position. The developing cartridge includes a cover member that covers at least a portion of the operation portion in a state in which the drum cartridge is mounted to the drawer, and the developing cartridge is mounted to the drum cartridge.

A developing roller is located nearer a first end than a second end in a first direction. A first boss extends in a second direction and is movable together with a housing. The first boss bears the weight of a developer cartridge when the first boss is supported by a support surface of a first side plate of a drum unit, and is located away from the developing roller in the first direction and the third direction. A first pressure receiving surface is located farther away from the developing roller than the first boss in the third direction. The pressure receiving member receives a pressing force in the third direction from a pressing member of the first side plate of the drum unit. The first boss is located away from the developing roller in the first direction by a first distance. The first pressure receiving surface is located away from the developing roller in the first direction by the first distance or by a second distance smaller than the first distance.

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.

An image forming apparatus includes a drum unit, a developing device, a development holder, and a sliding member. The drum unit includes a photosensitive drum. The developing device includes a developing roller. The development holder is swung so as to bring and separate the developing roller close to and apart from the photosensitive drum. The sliding member is slidable in an axial direction of the developing roller. The development holder is swung so as to bring the developing roller close to the photosensitive drum in association with a sliding of the sliding member from a first position to a second position, and the development holder is swung so as to separate the developing roller apart from the photosensitive drum in association with a sliding of the sliding member from the second position to the first position.

An image forming apparatus is provided, including a housing; a drum cartridge; a developing cartridge; a drawer movable between an inner position and an outer position; and a lock member provided on the drawer and movable between a lock position at which the lock member locks the drum cartridge to the drawer, and a release position at which a lock between the drum cartridge and the drawer is released. The lock member includes an operation portion for moving the lock member between the lock position and the release position. The developing cartridge includes a cover member that covers at least a portion of the operation portion in a state in which the drum cartridge is mounted to the drawer, and the developing cartridge is mounted to the drum cartridge.

An image forming apparatus has a body frame and a slide frame. The slide frame is configured to be pulled out from the body frame along a sliding direction. A plurality of image forming cartridges is detachably mounted on the slide frame. A plurality of electrode members is mounted on the slide frame and aligned along the sliding direction so as to correspond to the image forming cartridges. A body-side contact portion of each of the electrode members is electrically connected to the body frame. A cartridge-side contact portion of the electrode member is electrically connected to the image forming cartridge. The image forming cartridge is connected to the body via the corresponding electrode member when the slide frame mounting the image forming cartridges is inserted to the body frame.