| 摘要 |
PROBLEM TO BE SOLVED: To prevent occurrence of deterioration of productivity when switching between a pressure-contact state and a separation state. SOLUTION: This image forming apparatus constituted to transfer a toner image formed by an electrophotographic process onto a recording medium from an image carrier (an intermediate transfer belt) has a toner density detection sensor, a transfer member (a secondary transfer roller) movable between the pressure-contact state and the separation state of the image carrier, a pressure-contact/separation mechanism, a pressure-contact/separation detection sensor for detecting the pressure-contact state and the separation state of the transfer member, and a control part. The control part generates a pattern for detecting pressure-contact/separation for detecting the pressure-contact state and the separation state of the transfer member of the image carrier, lets the toner density detection sensor detect density of the pattern for detecting pressure-contact/separation, and determines whether the transfer member is in the pressure-contact state or the separation state based on the detected density if it determines that output from the pressure-contact/separation detection sensor is abnormal. COPYRIGHT: (C)2010,JPO&INPIT |
