| 摘要 |
PURPOSE:To efficiently exchange a photosensitive body which is almost dead based on rotating time from the time of being set, etc., by detecting that an unused photosensitive body is set without comparatively making a cost high. CONSTITUTION:A member 52 to be detected which is on a first position shown by a continuous line when it is unused and moves to a second position shown by a virtual line when it is set to a device main body and the photosensitive body 2 is turned is provided on the attachable/detachable photosensitive unit 2. Also a photointerrupter (detecting means) 5 detecting whether the member 52 is on the second position or not is provided, by which first detection is executed, then after the photosensitive body 3 is turned and a specified time is elapsed, second detection is executed so that whether the unused photosensitive unit 2 is set or not can be detected based on the combination of detection results. |
