Development cartridge, process cartridge, and image forming apparatus

A cartridge which is attachable, through an opening, to an apparatus main body of an image forming apparatus that has the opening and an opening and closing member that is configured to be movable between an open position where the opening is opened and a close position where the opening is closed, and to which a developer container having developer contained therein is detachably attachable, the cartridge comprising:

• a developer carrier that carries developer on a surface thereof;
• a blade that regulates thickness of the developer;
• an attachment portion to which the developer container is attached, the attachment portion being configured so that the developer container is movable between a first position and a second position different from the first position in a state where the developer container is attached to the attachment portion;
• and
• a moving member that is configured to be movable to be at different positions between a case where the developer container is attached at the first position of the cartridge and a case where the developer container is attached ab the second position of the cartridge, in a case where the cartridge in which the developer container is attached at the first position is attached to the attachment portion, the moving member being at a position of preventing movement of the opening and closing member from the open position to the close position, and in a case where the cartridge in which the developer container is attached at the second position is attached to the attachment portion, the moving member being at a position of allowing movement of the opening and closing member from the open position to the close position.