| 摘要 |
PURPOSE:To always stabilize the electrified potential of a photosensitive body at a desired one by controlling an electrifier based on the measured value of a potential sensor whose output is calibrated so that the surface potential of the photosensitive body can be electrified to a fixed potential. CONSTITUTION:Whenever the main switch of the image forming device, for instance, is turned on, a 1st switching means 37 is switched. In response to that switching, the photosensitive body 21 is biased to a predetermined high voltage, and the measured value of the potential sensor at that time is read out. An electrifier control means 35 controls an output from the electrifier 23 to electrify the surface of the photosensitive body, and at the same time the output of the electrifier 24 is adjusted so that the output from the potential sensor 24 can be equal to the read-out measured value. In such a way, the title device is provided with the potential sensor 24 detecting the surface potential of the photosensitive body, and a circuit automatically calibrating the output of the potential sensor at a fixed timing, whereby the output from the potential sensor measuring the surface potential of the photosensitive body can be one which is always calibrated. Thus, the photosensitive body can be electrified at a desired potential. |
