Patent ID: 11927894
Assignee: CANON KABUSHIKI KAISHA
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 21:
22. An image forming apparatus comprising:
an image forming portion provided with a rotatable image bearing member on which an electrostatic latent image corresponding to image information is formed, and a developing member contacting the image bearing member at a developing position and configured to develop the electrostatic latent image on the image bearing member with a developer;
an intermediary transfer member onto which an image formed with the developer is transferred from the image bearing member at a primary transfer position;
a transfer device configured to transfer the image formed with the developer from the intermediary transfer member to a recording material at a secondary transfer position;
a common driving source configured to drive the image bearing member, the developing member, and the intermediary transfer member;
a contact-and-separation mechanism configured to cause the developing member to contact or separate from the image bearing member; and
a controller configured to control the contact-and-separation mechanism,
wherein in a case that the developing member is separated from the image bearing member when an operation in which the image is transferred to an image forming area on the intermediary transfer member from the image bearing member is terminated, the controller controls, based on presence or absence of the recording material at the secondary transfer position when development is terminated, to switch and execute a first control in which the developing member is started to separate from the image bearing member after an end portion of an image forming area on the image bearing member with respect to a moving direction of a surface of the image bearing member passes through the primary transfer position, and a second control in which the developing member is started to separate from the image bearing member after the end portion of the image in the image forming area on the image bearing member with respect to the moving direction of the surface of the image bearing member passes through the developing position and before the end portion of the image forming area reaches the primary transfer position.