A developing device includes a developer cartridge and a developing unit. The developer cartridge, in some instances, may include a shutter. This shutter may have a wall for closing a developer supply hole, and be movable, with respect to a developer cartridge casing, between an open position where the supply hole is opened by the wall and a closed position where the supply hole is closed by the wall. The shutter may further include a protrusion that is movable with respect to the wall of the shutter between a first position and a second position in an axial direction. The protrusion, in the first position, is engageable with a developing unit and, in the second position, would be disengaged from the developing unit.

Disclosed is a developing apparatus including: a developer bearing member that bears a developer; a developing frame body that rotatably supports the developer bearing member; a one-end side end member that supports one-end side in an axis direction of the developer bearing member of the developing frame body; and another-end side end member that supports the other-end side in the axis direction of the developer bearing member of the developing frame body. Each of the one-end side end member and the other-end side end member is independently movable with respect to the developing frame body.

An image forming apparatus includes a development cartridge having a developing roller. The developing roller includes a roller body, and a shaft to pass through a central axis of the roller body. A coupling structure is disposed at an end part of the shaft, is movable from a first position to a second position, and includes a first coupling piece and a second coupling piece. Positions of the first coupling piece and the second coupling piece are maintained with respect to one another by a static frictional force between surfaces of the first coupling piece and the second coupling piece to hold the coupling structure in the first position. When a predetermined force overcomes the static frictional force, the first coupling piece and the second coupling piece disengage from one another to allow the coupling structure to move from the first position to the second position.

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.

An image forming apparatus including a main body casing, a cover, a drum cartridge, a developing cartridge, an intermediate transfer belt and a movable cam. The movable cam is movable among a first position when the cover is in the open position, a second positon and a third position when the cover is in the closed position. In a case where the movable cam is in the first position, the photosensitive drum is in a first drum position spaced from the intermediate transfer belt, and the developing roller is in a first developing position spaced from the photosensitive drum. In a case where the movable cam is in the second position, the photosensitive drum is positioned toward the the intermediate transfer belt from the first drum position. In a case where the cam is in the third position, the developing roller is positioned toward the photosensitive drum from the first developing position.

A developing cartridge and an electronic imaging apparatus, where the developing cartridge is detachable installed in the electronic imaging apparatus, and includes a cartridge, a power reception member, a rotary member and an activation member; the cartridge includes a first side wall and a second side wall provided opposite to each other along a first direction, where a power reception member is located at the first side wall, a rotary member is installed between the first side wall and the second side wall, one end of the rotary member is provided with a first gear, and the other end of the rotary member is provided with a second gear, an activation member is located at the second side wall; and the activation member includes a movable member and a trigger part provided at the movable member.

A developing cartridge includes: a casing; a developing roller extending in a first direction; a boss movable with the casing; and a first lever movable relative to the casing. The first lever includes: one end portion functioning as a point of effort; another end portion functioning as a point of load; a shaft functions as a fulcrum and positioned between the one end portion and the another end portion; and a first hole into which the boss is fitted. By the one end portion receiving a driving force, the first lever is pivotally movable about the shaft. A dimension of the first hole in a second direction crossing the first direction is greater than a dimension in the second direction of the boss. In a case where the casing moves in the second direction relative to the first lever, the boss moves in the second direction within the first hole.

An image forming apparatus includes a drive source, an object configured to be driven by the drive source, and a drive transmission mechanism including a driving member, a driven member, an intermediate member, an urging member, and an actuating portion. The intermediate member is configured to move in an axial direction. The intermediate member includes a shaft portion extending in the axial direction, and a positioning portion configured to determine a position of the driven member in a direction orthogonal to the axis. The shaft portion includes a receiving portion configured to receive a force. The receiving portion is positioned inward of the positioning portion in a radial direction of rotation of the intermediate member.

An image forming apparatus including a photosensitive member, a developing cartridge that has a developing member, a developing frame, an end member attached to the developing frame, and a restricting portion restricting a swing movement of the end member, and an apparatus body to which the developing cartridge is attachable. The apparatus body includes a movement unit moving the developing cartridge from a first position to a second position, a positioning portion engaging with the end member when the developing cartridge is located at the second position, and a restriction releasing portion acting on the restricting portion with a movement of the developing cartridge from the first position to the second position and releasing restriction of the swing movement of the end member, the restriction releasing portion being provided at a part of the apparatus main body excluding the movement unit.

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.