| 摘要 |
PURPOSE:To eliminate variation in recording picture quality due to the fatigue of a photosensitive body by switching an electrostatic charging current or voltage for electrostatic charging operation after a preset number of records or time corresponding to them. CONSTITUTION:An image exposing part 3 projects an image of an original to be copied on the photosensitive body 1a to form a latent image, which is developed by a developing part 4 to obtain a toner image. A temperature sensor 5 is provided nearby the photosensitive body 1a to detect the temperature of the photosensitive body 1a and a control part performs control according to a current value to switch current values according to the number of continuous copies from a copy counter, for example, after the 20th copy and the 70th copy are taken. In this case, magnification corresponding to a standard current value is determined with temperature information from the temperature sensor 5. The control part has a timer, so the time from the point of time when continuous copying operation is completed is measured and used as a factor for the determination of the current value at the start of next copying operation which is 3min and 20min later. This control which is combined in a matrix starts restarts from the beginning when a main switch is turned off. |
