Patent ID: 7885554

Claim:
A developing device that can be mounted to and dismounted from a mounting and dismounting section provided in an image forming apparatus main unit, the developing device comprising: a developing device main unit; a positioning member for positioning the developing device main unit with respect to the mounting and dismounting section by engaging the mounting and dismounting section when the developing device is mounted to the mounting and dismounting section, the positioning member being fixed on a one end side in a longitudinal direction of the developing device main unit; a coupling member that is to be coupled to the mounting and dismounting section when the developing device is mounted to the mounting and dismounting section, the coupling member being attached to the other end side in the longitudinal direction of the developing device main unit in such a manner that its relative position to the developing device main unit can be changed; and an element capable of communication in a noncontacting manner with the image forming apparatus main unit side when the developing device is mounted to the mounting and dismounting section, the element being provided at the one end side in the longitudinal direction of the developing device main unit.