Patent ID: 7805098

Claim:
A development device comprising: a developing tank, which is detachable, for containing a two component developer including toner and carrier; a toner supply device for containing toner and supplying the toner to the developing tank; a communicating chamber between a supply opening and a receiving opening, for communicating an inside of the toner supply device and an inside of the developing tank, wherein the supply opening is formed on the toner supply device and the receiving opening is formed on the developing tank and receives the toner from the supply opening; and a shutter member being supported rotatably in the communicating chamber, for opening and shutting the supply opening in conjunction with an attachment and detachment operation of the developing tank, wherein a rotational axis of the shutter member is arranged parallel to an insertion and removal direction of the developing tank, the shutter member comprising a roller-shaped main section with an open section formed extending in an axial direction thereof as well as opened in a direction perpendicular to the axial direction, for shutting the supply opening by covering the supply opening with an outer surface of the roller-shaped main section, and opening the supply opening by communicating the supply opening and the receiving opening through the open section.