| 摘要 |
PURPOSE:To evade the abnormal discharge of a corona wire causing a failure and to suppress the increase of the quantity of generated ozone by controlling a voltage applied by means of a bias voltage applying means, based on the detected residual potential of a photosensitive body. CONSTITUTION:This image forming device is composed of the photosensitive body 101, an electrifier 102 for electrostatically charging the photosensitive body 101 by discharge, a high voltage applying power source 103 supplying the voltage for the discharge, to the electrifier 102, a developing roller 104 preventing toner from being excessively stuck to the photosensitive body, a middle voltage applying power source 105 supplying the voltage to the developing roller 104, a voltage applying power source 106 applying the voltage to the photosensitive body 101, a potential sensor 107 measuring the residual potential of the photosensitive body 101, and a main control part 108 controlling each part. Then, the voltage previously applied to the photosensitive body, is dropped by a prescribed value, accompanying with the increase of the residual potential, and differences between a developing bias and the residual potential, and between the potential by electrification and the developing bias, are equalized to a value in an initial state, even in the lapse of time. |
