The image forming apparatus includes a cartridge replaceable by detachably mounting to the image forming apparatus, a door that takes a closed state or an open state, a locking pin that switches a state of the regulation unit between a regulating state in which the replacement unit is prevented to be detached from the image forming apparatus and a release state in which the replacement unit is to be detachable from the image forming apparatus, and a lock control unit (a control unit) that makes a determination as to whether or not the state of the regulation unit is to be switched from the release state to the regulating state, at a predetermined timing when initial processing is completed after a power source is turned on or a state of the door becomes the closed state from the open state.

An image forming apparatus includes an image carrier unit, a developing unit, a supporting frame, a retainer and a sheet member. The image carrier unit includes an image carrier on which an electrostatic latent image is formed. The developing unit develops the electrostatic latent image with toner. The supporting frame supports the image carrier unit and the developing unit in an attachable and detachable manner. The retainer is supported by the supporting frame in a turnable manner, and positions the image carrier unit and the developing unit to the supporting frame by being turned upward. The sheet member closes a gap between the supporting frame and the retainer. The sheet member has an upper section supported by the retainer and a lower end section supported by the supporting frame, and at least one of the upper end section and the lower end section is configured to be detachable.

A developing cartridge includes a storage medium. A first contact portion is provided in a photoconductor unit and configured to be electrically connected to the storage medium. A second contact portion is provided in an apparatus body. The photoconductor unit is configured to, in a case of attaching the photoconductor unit to the apparatus body, move from a first position to a second position while being guided by a guide member and then move from the second position to a third position below the second position. At least one of the first contact portion and the second contact portion is capable of being displaced such that engagement between the first contact portion and the second contact portion is performed while the photoconductor unit moves by being guided by the guide member, and the engagement is maintained while the photoconductor unit moves from the second position to the third position.

An image forming apparatus configured to form an image on a sheet, the image forming apparatus includes an apparatus body, and a detachable unit. The detachable unit includes a first positioned portion and a second positioned portion. The apparatus body includes a frame member having a first positioning portion and a second positioning portion which respectively engage with the first positioned and second positioned portion, so that the detachable unit is positioned with respect to frame member in the attaching direction and the first direction. The second positioning portion is arranged closer to a center portion of the detachable unit in the second direction than the first positioning portion.

In an image forming apparatus, a tray unit to which a cartridge is detachably mounted, and that is configured to be capable of moving between an internal position situated within the apparatus main body and an external position situated outside, includes first and second side plates configured to support the cartridge, and they are each made of metal, and include a supporting portion and an outer side portion, the supporting portions includes positioning portions configured to come into contact with the cartridge to position the cartridge as to an image forming position. The apparatus main body includes first and second pressing members each capable of moving between pressing positions at which the cartridge is pressed, and separated positions separated from the cartridge. The first and second pressing members are disposed each intersecting with imaginary planes that is orthogonal to the longitudinal direction and intersect the positioning portions.

A cartridge frame includes a protruding rib protruding toward a first frame, a first bearing supporting one end of a photosensitive drum in an axial direction, and a second bearing supporting an other end of the photosensitive drum in the axial direction. The first frame includes a first guide rail configured to, when a process cartridge is attached to an apparatus main body, guide the protruding rib to slide along the first guide rail. A second frame includes a second guide rail configured to, when the process cartridge is attached to the apparatus main body, guide the second bearing to slide along the second guide rail. A size of the first guide rail in a width direction perpendicular to both the axial direction and an attachment direction of the process cartridge is smaller than a size of the second guide rail in the width direction.

One of two walls apart from each other in a first direction has an opening. A drum cartridge includes a photosensitive drum rotatable about a drum axis extending in the first direction when the drum cartridge is attached to a housing. The drum cartridge is movable through the opening between a first position at which an entirety of the drum cartridge is located inside the housing and a second position at which at least part of the drum cartridge is located outside the housing. The development cartridge includes a development roller rotatable about an axis extending in the first direction. The development cartridge is unattachable to and undetachable from the drum cartridge in a state where the drum cartridge is located at the first position. The development cartridge is attachable to and detachable from the drum cartridge in a state where the drum cartridge is located at the second position.

A drawer is moveable between an inner position and an outer position through an opening when a cover is located at an opening position. A waste toner conveying tube is movable in a second direction between a first connection position and a first disconnection position when a drum cartridge is attached to a drawer and the drawer is at the inner position. When the cover moves from a closing position toward the opening position, the waste toner conveying tube moves from the first connection position toward the first disconnection position in conjunction with the movement of the cover. The drawer is movable from the inner position toward to the outer position when the drum cartridge is attached to the drawer, the drawer is at the inner position, and the waste toner conveying tube is at the first disconnection position.

An image forming apparatus of the present invention includes: a body; a developing cartridge having a memory medium and a developer bearing member; a tray including a frame which is movable between a housed position and a drawn-out position and has side portions extending in the moving direction and to which the developing cartridge is attachable, an image bearing member that faces the developer bearing member when the developing cartridge is attached, a tray-side metal terminal provided on the side portion and electrically connected to the memory medium when the cartridge is attached, and a tray guide portion extending along the moving direction; a body-side metal terminal that faces the tray-side metal terminal when the tray is housed, wherein the tray-side metal terminal is provided below the tray guide 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.