An image forming apparatus includes a main body casing; a first drum unit including a first photosensitive drum configured to rotate about an axis extending in a first direction; a second drum unit including a second photosensitive drum configured to rotate about an axis extending in the first direction; a belt; a cleaning member configured to clean the belt; an auger configured to convey waste toner cleaned by the cleaning member; a first toner cartridge including a first new toner containing unit configured to supply new toner and a waste toner containing unit configured to contain the waste toner conveyed by the auger; and a second toner cartridge including a second new toner containing unit configured to supply new toner to the second drum unit. The waste toner containing unit is aligned with the first new toner containing unit in a second direction perpendicular to the first direction.

A developing unit and a photosensitive unit respectively have engaging mechanism parts that fit in each other in the longitudinal direction so as to integrate the developing unit and the photosensitive unit. The developing unit includes, as the engaging mechanism part, a first holding member to hold the front end part of a drum shaft. The photosensitive unit includes, as the engaging mechanism part, a second holding member to hold the rear end part of a roller shaft. The first holding member and the second holding member are provided in a slidable manner in a direction in which the developing roller and the photosensitive drum separate from each other, and furthermore are biased toward a direction in which the developing roller and the photosensitive drum come close to each other.

A developing unit and a photosensitive unit respectively have engaging mechanism parts that fit in each other in the longitudinal direction so as to integrate the developing unit and the photosensitive unit. The developing unit includes, as the engaging mechanism part, a first holding member to hold the front end part of a drum shaft. The photosensitive unit includes, as the engaging mechanism part, a second holding member to hold the rear end part of a roller shaft. The first holding member and the second holding member are provided in a slidable manner in a direction in which the developing roller and the photosensitive drum separate from each other, and furthermore are biased toward a direction in which the developing roller and the photosensitive drum come close to each other.

An image forming apparatus includes a main body casing having a front side wall having a plurality of cartridge ports and a tray port, each of the plurality of cartridge ports extending in a first direction and being aligned in a second direction; a reading scanner unit provided above the main body casing; and a sheet discharging unit configured to discharge a sheet and positioned between an upper side wall of the main body and the reading scanner unit. The apparatus further includes a sheet feeding unit positioned below a door provided on the front side wall; a plurality of toner cartridges which are attached to the plurality of cartridge ports; and a plurality of photosensitive drums being detached from the main body casing in the second direction, each of the plurality of toner cartridges being spaced apart from the plurality of photosensitive drums in a third direction.

An image forming apparatus includes an intermediate transferor to rotate in a predetermined rotation direction, a plurality of image bearers disposed along the intermediate transferor to bear latent images, a plurality of developing devices to develop the latent images, a plurality of developer containers to contain developers, and a plurality of conveyance paths each corresponding to a respective one of the plurality of developing devices and a respective one of the plurality of developer containers to supply the developers to the plurality of developing devices respectively. An arrangement of the plurality of developing devices in the predetermined rotation direction is configured to be changed without changing an arrangement of the plurality of developer containers. A layout of the plurality of conveyance paths is configured to be changed without changing connections between a supply source and a supply destination of the plurality of conveyance paths.

An image forming apparatus includes an intermediate transferor to rotate in a predetermined rotation direction, a plurality of image bearers disposed along the intermediate transferor to bear latent images, a plurality of developing devices to develop the latent images, a plurality of developer containers to contain developers, and a plurality of conveyance paths each corresponding to a respective one of the plurality of developing devices and a respective one of the plurality of developer containers to supply the developers to the plurality of developing devices respectively. An arrangement of the plurality of developing devices in the predetermined rotation direction is configured to be changed without changing an arrangement of the plurality of developer containers. A layout of the plurality of conveyance paths is configured to be changed without changing connections between a supply source and a supply destination of the plurality of conveyance paths.

An image forming apparatus includes a housing; a partition wall which is provided in the housing along a substantially vertical direction, the partition wall partitioning an inner space of the housing into a first space and a second space; developing units which are disposed in parallel along the substantially vertical direction in the first space, each of the developing units comprising a first reception opening and a return opening; and developer cartridges which correspond to the plurality of developing units, the developer cartridges being disposed in parallel along the substantially vertical direction in the second space, each of developer cartridges comprising a supply opening and a second reception opening. The first reception openings of the developing units communicate with the supply openings of respective ones of the developer cartridges, and the return openings of the developer units communicate with the second reception openings of respective ones of the developer cartridges.

An image forming apparatus includes: a main body having an opening; a photoconductor unit including a photoconductor and removably mountable to the main body through the opening by moving the photoconductor unit in a first direction; an exposure member; and a moving mechanism configured to move the exposure member closer to and further from the photoconductor. The moving mechanism includes: a fixed shaft having an axial line thereof fixed relative to the main body; a first arm including one end portion thereof which is supported rotatably around the axial line of the fixed shaft; a movable shaft having an axial line thereof which is movable relative to the main body; and a second arm including: one end portion supporting the exposure member; and another end portion connected to the first arm via the movable shaft, and the second arm being swingable around the axial line of the movable shaft.

A method of assembling a belt conveyance apparatus having an endless belt, a plurality of rollers, a frame, a bearing holder, an urging member, a slider, and a driving gear includes the steps of: in a state without the driving gear mounted to the frame, arranging the slider in a disengaged position; attaching the bearing holder and the urging member to the frame; moving the slider in an engaged position so that it engages with the bearing holder; and attaching the driving gear to the frame so that it meshes with the slider arranged in the engaged position.