| 摘要 |
PURPOSE:To optimize the exchange period of a photoreceptor. CONSTITUTION:Between a primary current Idc flowing at the time of electrifying a photoreceptor drum 9 with an electrifying roller 10 and the film thickness (d) of the photosensitive layer of the drum 9, Idc=k/d (where, K is a constant) is established. Therefore, the primary current signal Idc 23 is monitored by a film thickness detecting part 20, to infer the film thickness (d) of the drum 9. Thus, a change in the film thickness (d) of the drum 9 caused by endurance, that is, the electric characteristics of the drum 9 can be accurately grasped and the exchange period of the photoreceptor can be optimized. |
