Abstract: An electrophotographic image forming apparatus includes a main body; an image formation unit removably mounted to the main body and having at least two cartridges disposed adjacently to each other; a plurality of memory members disposed on each cartridge to face one another; and a communication unit disposed among the memory members for communication with the memory members.

Abstract: A structure to maintain a steady rotation speed of an optical photoconductor in an electrophotographic image forming apparatus. The structure includes a frame; an optical photoconductor which has a cylindrical shape on an outer surface of which an electrostatic latent image is formed by an optical scan, the optical photoconductor comprising a looped protrusion protruding from an end portion in a lengthwise direction of the optical photoconductor and a rotation shaft installed to be capable of rotating with respect to the frame; a damper installed at an end of the optical photoconductor, the damper comprising a core having a through hole, through which the rotation shaft of the optical photoconductor passes, and a wing, which extends from an outer circumference of the core, contacts and presses an inner circumference of the looped protrusion; and a rotation preventing unit which prevents the damper from rotating depending on rotation of the optical photoconductor.