An image forming apparatus includes a first moving member moving between a first position which is a position not in contact with a recording material and a second position which is a position in contact with the recording material, and a second moving member positioned in a third position in a state where an attachable/detachable unit is not attached to an apparatus main body and in a fourth position in a state where the attachable/detachable unit is attached to the apparatus main body. An optical sensor includes a light-emitting portion and a light-receiving portion, and a flag member moves between a transmission position and a light-shielding position and moves in conjunction with movement of the first moving member from the first position to the second position and with a movement of the second moving member from the third position to the fourth 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.

An image forming apparatus includes a main body provided with a mounting portion and an interference member, and a toner cartridge inserted into the mounting portion. The toner cartridge includes a housing containing toner, a coupling portion, a front cover coupled to one end of the housing via the coupling portion, and a switching member to weaken a coupling force of the coupling portion by interfering with the interference member when the toner cartridge is mounted on the mounting portion.

Movement and/or urging of a developer carrying member is carried out with high precision. A cartridge that is mountable to an apparatus main assembly of an image forming apparatus, the cartridge includes a developing roller; a frame supporting the developing roller; a movable part movably supported by the frame and movable to a first position and to a second position relative to the frame; and an elastic part provided between the frame and the movable part to urge the movable part. The movable part includes a first force receiving part that receives force from the apparatus main assembly, in a direction of moving from the first position to the second position, and a second force receiving part that receives force from the apparatus main assembly, in a direction of moving from the second position to the first position. When the movable part receives force from the apparatus main assembly at the first force receiving part and is at the second position, the movable part receives urging force from the elastic part in a direction of moving the movable part from the second position to the first position.

A cartridge includes a photosensitive drum and a coupling member for transmitting a driving force to the photosensitive drum. A movable member is provided movable relative to a frame and a rotatable portion is supported by the movable member and rotatable relative to the movable member. A regulating member is movable between a regulating position for regulating movement of the movable member by contacting the rotatable portion and a non-regulating position where the regulating member does not regulate the movable member. A position of an end portion of the movable member in an axial direction of the photosensitive drum changes relative to the frame by movement of the movable member between a first position and a second position, and the end portion of the movable member is closer to the coupling member in the axial direction of the photosensitive drum when the movable member is in the second position than when the movable member is in the first position. When the regulating member is in the regulating position, the movable member is constrained from moving from the first position to the second position, and, when the regulating member is in the non-regulating position, the movable member is permitted to move from the first position to the second position.

An image forming apparatus includes an apparatus housing, and an imaging module that is removably installed in the apparatus housing. The imaging module includes an image carrier unit that is capable of carrying an image, an image writer unit that writes an image on the image carrier unit, and a module housing that registers and removably holds the image carrier unit and the image writer unit. A fastening unit that registers the module housing with respect to the apparatus housing and that removably fastens the module housing is disposed between the apparatus housing and the module housing.

A pull-in apparatus configured to pull in a unit toward a predetermined position in an apparatus body includes an arm member, a restriction member, a first action portion and a second action portion. The restriction member is movable between a lock position at which the restriction member restricts movement of the arm member in a first direction and a lock-release position at which the restriction member allows the movement of the arm member in the first direction. Movement of the restriction member from the lock position toward the lock-release position is restricted in a state in which the arm member is at a stand-by position, and is allowed in a state in which the arm member has been moved from the stand-by position in a second direction.

An image forming apparatus includes an apparatus main body, a process cartridge, a scanner unit, and a toner cartridge. The process cartridge is detachably mounted on the apparatus main body. The process cartridge includes: a photosensitive drum configured to rotate about a rotational axis extending in a first direction; and a development unit configured to supply toner to the photosensitive drum. The toner cartridge is configured to store toner. At least part of the photosensitive drum, at least part of the scanner unit, and at least part of the toner cartridge are aligned in a second direction in this order. The second direction is perpendicular to both the first direction and to a vertical direction. The at least part of the photosensitive drum, the at least part of the scanner unit, and the at least part of the toner cartridge overlap one another as viewed from the second direction.

A cover covering an image bearing member such that the image bearing member is kept unexposed includes a holding portion holding an end portion of a sealing sheet sealing an opening portion such that an initial developer is accommodated in an accommodating chamber, due to release of the seal of the opening portion with the sealing sheet, the initial developer accommodated in the accommodating chamber moves from the accommodating chamber to a second chamber through the opening portion, and the seal of the opening portion with the sealing sheet is released due to movement of a casing with respect to the cover and detachment of the cover from the casing, responsive to an operation of movement of a cartridge in an attachment direction, with the holding portion holding the end portion of the sealing sheet and a regulation portion regulating movement of the cover.

A developing cartridge includes: a developing roller; a casing having an outer surface; a first shaft rotatable about a rotational axis; a first arm; and a cam. The first arm and the cam extend radially outward from an outer periphery of the first shaft and pivotally movable along with rotation of the first shaft. The cam has: one end connected to the first shaft; another end positioned farther from the rotational axis than the one end is farther from the rotational axis; and a pressure contact surface inclined so as to approach the outer surface of the casing as extending from the one end toward the another end. When a pressing force is applied to the pressure contact surface, the first arm pivotally moves from a first position to a second position along with: pivotal movement of the cam; and the rotation of the first shaft.