Image forming apparatus that employs electrophotographic method

摘要

The formation position of a primary-transferred toner image is corrected by using, as a reference, a timing at which a marker that rotates together with a rotating member is detected by a marker detecting unit for detecting the marker, after part of a preparation operation in which a processing unit is caused to contact or depart from the rotating member is finished.

主权项

1. An image forming apparatus comprising:
an image bearing member configured to bear a toner image; an exposure unit configured to form a latent image on the image bearing member; a development unit that includes a plurality of developing devices that each develop the latent image by using a toner of a different color, and rotates to switch the developing device contacting the image bearing member, such that another of the developing devices contacts the image bearing member; a rotating member configured to operate as an intermediate transfer member onto which the toner image formed on the image bearing member is primary-transferred, or as a transferring material bearing member that bears a recording material onto which the toner image is primary-transferred and rotates; and a correcting unit configured to correct a formation position of a toner image according to a number of the developing devices passing through a developing position until the toner image is formed on the image bearing member after any one of the plurality of developing devices stops at the developing position by the development unit rotating the plurality of developing devices.