Patent ID: 7110702

Claim:
A developing apparatus comprising: a plurality of developing containers, each containing developer including toner and a carrier, each of said plurality of developing containers having a first chamber provided with a developer carrying member for carrying the developer to develop an electrostatic image formed on an image bearing member, and a second chamber constituting a circulation route for the developer between said first chamber and said second chamber; a carrying member for carrying the developer in said second chamber; an opening portion provided in a side of said second chamber for permitting the overflow of an excess developer with a supply of the developer; and a rotary member rotatable with said plurality of developing containers held thereon, said rotary member being adapted to selectively position a desired developing container at a developing position, wherein in a state in which the desired developing container is positioned at the developing position, a height of a ceiling of said second chamber near said opening portion is greater than a height of the ceiling of said second chamber on an upstream side and a downstream side of said opening portion with respect to a developer carrying direction.