| 摘要 |
PURPOSE:To improve the job efficiency of a copying machine by preventing the copying machine from being stopped even when electrostatic charging output for attaining a reference toner adhesive quantity is not obtained. CONSTITUTION:This device is provided with an optical sensor 14 for detecting the toner sticking amount on the surface of a photosensitive drum, and a control processing part 20 obtaining the electrification output of an electrifier for making a value detected by the sensor 14 satisfy the previously set reference toner sticking amount, and controlling the output of a grid bias power source 19 so that the electrification output may be corrected by setting a difference between the obtained electrification output and the reference electrification output of the electrifier as a correction amount, while controlling the output of the power source 19 so that the electrification output may be specified constant times as large as the previously set reference output value in the case the electrification output which becomes a reference value is not obtained. |
