Patent ID: 11953846
Assignee: CANON KABUSHIKI KAISHA
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. An image forming apparatus comprising:
an image forming portion configured to form a toner image;
a rotatable intermediary transfer belt onto which the toner image formed by said image forming portion is transferred;
an inner roller contacting an inner peripheral surface of said intermediary transfer belt and configured to stretch said intermediary transfer belt;
a transfer unit contactable to an outer peripheral surface of said intermediary transfer belt and configured to form a transfer nip, where the toner image is transferred from said intermediary transfer belt onto a recording material, by nipping said intermediary transfer belt between said transfer unit and said inner roller, said transfer unit including an outer roller configured to form the transfer nip between said outer roller and said inner roller;
a contact and separation mechanism configured to bring said transfer unit into contact with and separation from said intermediary transfer belt;
a position changing mechanism configured to change a position of the transfer nip with respect to a circumferential direction of said inner roller by changing a position of said inner roller relative to said outer roller; and
a controller configured to control said position changing mechanism and said contact and separation mechanism,
wherein in a case that a mode, in which the position of said inner roller is changed by said position changing mechanism in a period after a trailing end of a preceding recording material reaches the transfer nip and before a leading edge of a recording material subsequent to the preceding recording material reaches the transfer nip during execution of a continuous image forming job for forming and outputting images on a plurality of recording materials is executed, in the period, said controller controls said position changing mechanism to change the position of said inner roller in a state in which said transfer unit contacts said intermediary transfer belt.