Patent ID: 7233756
Filing Date: 2007-06-19
Classification: G03G

Abstract:
1. An image forming apparatus comprising: an image bearing member on which an electrostatic image is formed; a developing device, which develops the electrostatic image in a developing position, which is opposite to said image bearing member, said developing device including a developing container having a first chamber and a second chamber constituting a developer circulating route, a developer carrying member provided in said first chamber for carrying the developer to develop the electrostatic image, and an agitating and carrying member provided in said second chamber and having a spiral vane provided around a rotary shaft to agitate and carrying the developer; a rotary member holding said developing device and rotatable in a route including said developing position; supplying means for supplying the developer to said developing device, which is in said developing position; an opening, provided in a wall of said second chamber located above an upper end of said spiral vane of said agitating and carrying member and located downstream in a rotation direction of said agitating and carrying member in a region above a rotation center of said agitating and carrying member in said second chamber in a state in which said developing device is in said developing position, for discharging excess developer resulting from the supply of the developer by said supplying means through said opening to an outside of said developing device; and an opening and closing member provided so that one end of said opening and closing member is pivotally moved about a pivot center provided at the other end of said opening and closing member, said opening and closing member being pivotally moved to a position for opening said opening when said developing device is in the developing position, the one end of said opening and closing member being located downstream of the pivot center in the rotation direction of said agitating and carrying member.