Patent ID: 9091985
Filing Date: 2015-07-28
Classification: G03G

Abstract:
1. An image forming apparatus for forming a color image, comprising: a first photosensitive member and a second photosensitive member; a first motor and a second motor configured to rotate the first photosensitive member and the second photosensitive member, respectively; a detection section configured to detect rotation phases of the first photosensitive member and the second photosensitive member; a stop processing section configured to control the first motor and the second motor to stop the first photosensitive member and the second photosensitive member such that the rotation phase of the first photosensitive member and the rotation phase of the second photosensitive member have predetermined relations based on the detected rotation phases of the first photosensitive member and the second photosensitive member, after the end of image formation; a control section configured to drive the first motor and the second motor at predetermined time intervals without an image formation instruction to rotate the first photosensitive member and the second photosensitive member, respectively, after the stop processing by the stop processing section until a next image formation; a calculation unit configured to calculate a cumulative value of first rotation amounts of the first photosensitive member and a cumulative value of second rotation amounts of the second photosensitive member after the stop processing by the stop processing section; and a startup control section configured to control the first motor and the second motor to perform a startup process of the first photosensitive member and a startup process of the second photosensitive member based on a difference between the cumulative value of the first rotation amounts and the cumulative value of the second rotation amounts, wherein the startup control section delays the startup process of the first motor from the startup process of the second motor by a time period based on the difference between the cumulative value of the first rotation amounts and the cumulative value of the second rotation amounts when the cumulative value of the first rotation amounts is greater than the cumulative value of the second rotation amounts, and delays the startup process of the second motor from the startup process of the first motor by a time period based on the difference between the cumulative value of the first rotation amounts and the cumulative value of the second rotation amounts when the cumulative value of the second rotation amounts is greater than the cumulative value of the first rotation amounts for the next image formation.