Patent ID: 9703232
Date: 2017-07-11
CPC Classifications: G03G

Claim:
1. An image forming apparatus comprising: a plurality of image forming portions each including an image bearing member to be rotationally driven, charging means for electrically charging the image bearing member, exposure means for exposing the charged image bearing member to light to form a latent image including an exposed portion as an image portion, developing means, including a developing member movable toward and away from the image bearing member, for forming an image with a developer on the image bearing member by contacting the developing member with the image bearing member, and a cleaning member for removing the developer from the image bearing member in contact with the image bearing member; contact-and-separation means for moving the developing member toward and away from an associated one of the image bearing members of said image forming portions; a voltage source for applying, to the developing member, a developing voltage for urging the developer toward the image portion of the latent image on the image bearing member, wherein said image forming apparatus is capable of executing an operation in a mode in which the image is formed only at a part of said image forming portions, and the operation in the mode is executed in a state in which the developing member is contacted to the image bearing member at said part of said image forming portions where the image is formed and the developing member is separated from the image bearing member at another part of said image forming portions where the image is not formed and in which the image bearing members of said part of said image forming portions where the image is formed and said another part of said image forming portions where the image is not formed are driven; and control means for executing a contacting operation for contacting the developing member to which the developing voltage is applied with the image bearing member, charged by the charging means, for a predetermined period, wherein in the contacting operation, said exposure means does not form the latent image on the image bearing member, and wherein when the operation in the mode is continuously executed, said control means executes the contacting operation at said another part of said image forming portions where the image is not formed.