Patent ID: 7158740

Claim:
An image forming apparatus comprising: an image bearing member; a plurality of developing devices for developing electrostatic images formed on said image bearing member with developers, said plurality of developing devices including respective developer carrying members for carrying respective developers; and moving means for moving a selected one of said plurality of developing devices to an operative position, wherein each of said developer carrying members is movable selectively to be in contact with or spaced from said image bearing member at the operative position, wherein said apparatus is operable in a first image formation mode in which an image is formed using said plurality of developing devices and a second image formation mode in which an image is formed using one of said plurality of developing devices, and wherein said developer carrying member which is at the operative position in the first image formation mode is capable of being spaced from said image bearing member for a first duration during a non-developing operation, and said developer carrying member which is at the operative position in the second image formation mode is capable of being spaced from said image bearing member for a second duration during a non-developing-operation, and wherein the second duration is shorter than the first duration.