In a cartridge structure employing an inclinable coupling member engaging with a rotational force transmitting portion of an electrophotographic image forming apparatus, the coupling member is unable to engage with the rotational force transmitting portion of the electrophotographic image forming apparatus when the mounting and dismounting direction and the developing/spacing direction relative to the electrophotographic image forming apparatus of different from each other. Under the circumstances, a coupling lever contacting and retracting relative to the coupling member in interrelation with the mounting and dismounting operation of a developing cartridge B1, and a coupling spring for the coupling lever to apply an urging force to the coupling member are provided.

A cartridge includes a photosensitive drum having a rotational axis about which the photosensitive drum is rotatable, a developing roller having a rotational axis about which the developing roller is rotatable, and a casing rotatably supporting the photosensitive drum and the developing roller. The coupling member is operatively connected to the photosensitive drum, with the coupling member including at least one projection capable of receiving a rotational force to rotate the photosensitive drum. A spring is provided with a movable part that is movable relative to the casing in a direction away from the rotational axis of the developing roller to urge the coupling member so that at least the projection of the coupling member moves away from the rotational axis of the developing roller.

A developing cartridge includes a casing, a developing roller rotatable about an axis extending in a first direction, a developing memory having an electrical contact surface, an agitator, an agitator gear rotatable about an agitator axis together with the agitator, a holder holding the electrical contact surface, and a plate movable between a first position and a second position in a second direction crossing the first direction relative to the casing. The holder is movable relative to the casing in a third direction crossing the first and second directions between a retracted position and an advancing position. The holder is movable from the retracted position to the advancing position in response to a movement of the plate from the first position to the second position. The plate is positioned farther away from the developing roller than the agitator gear and the holder are in the second direction.

A cartridge is mountable in and dismountable from a main assembly of an image forming apparatus, in which the main assembly includes an opening and an openable member including a discriminating portion. The cartridge includes a process unit including a rotatable photosensitive member and a developing roller configured to supply toner to the photosensitive member, and a developer storage unit configured to store a developer. The developer storage unit is provided with a discharge opening for permitting discharge of the stored developer to the process unit and is mountable to and dismountable from the process unit. The developer storage unit is provided with a portion-to-be-discriminated provided so as to be engaged with the discriminating portion of the openable member when the cartridge is mounted in the main assembly and the openable member is in a closed position.

A first supporting member includes a first engaging portion and a second engaging portion that respectively engage with a first engaged portion and a second engaged portion that are provided in a second supporting member. The first engaging portion and the second engaging portion are configured to apply force in directions opposite to the directions in which the first engaged portion and the second engaged portion move when an opening opens.

A drum supporting member, which is usable with an image forming apparatus, includes a photosensitive drum and a mounting portion for detachably mounting a developing cartridge. The drum mounting portion also includes a contacting member contactable with the developing cartridge, with contacting member being movable between a first position and a second position. When the contacting member is in the first position, the contacting member contacts the developing cartridge with a developing roller of the developing cartridge being placed in a third position contacting the photosensitive drum. When the contacting member is in the second position, the contacting member contacts the developing cartridge with the developing cartridge being placed in a fourth position in which the developing cartridge is dismountable from the drum supporting member. The drum supporting member further includes an elastic member configured to urge the contacting member against movement of the developing cartridge in a direction from the fourth position to the third position.

To develop a conventional coupling for transmitting a driving force.

A coupling member is provided with a supporting portion for movable supporting a driving force receiving portion for receiving a driving force.

In a cartridge structure employing an inclinable coupling member engaging with a rotational force transmitting portion of an electrophotographic image forming apparatus, the coupling member is unable to engage with the rotational force transmitting portion of the electrophotographic image forming apparatus when the mounting and dismounting direction and the developing/spacing direction relative to the electrophotographic image forming apparatus of different from each other. Under the circumstances, a coupling lever contacting and retracting relative to the coupling member in interrelation with the mounting and dismounting operation of a developing cartridge B1, and a coupling spring for the coupling lever to apply an urging force to the coupling member are provided.

A drum cover is movable relative to a photosensitive drum between a first position at which the drum cover covers a part of a circumferential surface of the photosensitive drum, and a second position at which the drum cover does not cover the part of the circumferential surface of the photosensitive drum. A toner cartridge includes a toner storage portion configured to store toner to be supplied to the photosensitive drum. A drum cartridge includes a toner cartridge guide extending in a second direction crossing a first direction. The toner cartridge guide guides the toner cartridge to move in the second direction when the toner cartridge is being attached to the drum cartridge. A distance from the toner cartridge guide to the drum cover at the second position is longer than a distance from the toner cartridge guide to the drum cover at the first position.

An image forming apparatus in which a cartridge including an erroneous attaching prevention unit and a protruding portion as a holding unit, can be inserted to an attached position. The image forming apparatus includes a frame, an inclined surface on which the protruding portion is placed, the inclined surface being provided to the frame, a guide portion defining with the inclined surface a gap through which the protruding portion is able to pass, and a movable member configured to engage with the erroneous attaching prevention unit on a downstream side of the guide portion in an insertion direction.