| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus that improves the accuracy of steering control by obtaining contour shape data from which effect of periodic change in the widthwise position of a belt member resulting from a support rotor has been removed. <P>SOLUTION: In order to make the position of belt skew detected by a belt skew sensor reach a target value, a controller B1003 having a gain peak only for a specific frequency component is provided in addition to a controller A1001 that makes the position of belt skew reach a specific position. For the frequency of a signal extracted by the controller B1003, at least one rotation frequency is selected from the support rotor supporting an intermediate transfer belt. The controller B1003 has the gain peak in the selected rotation period. As a result, significant belt skew is prevented by the control that makes the position of belt skew reach the target value. Therefore, the amount of color shift resulting from frequency disturbance caused by a roller can be decreased. <P>COPYRIGHT: (C)2012,JPO&INPIT |
