| 摘要 |
PURPOSE:To improve the efficiency of maintenance operation by providing a non-volatile RAM and storing the tolerance of the surface potential of a photosensitive body in it. CONSTITUTION:A detecting analog signal from a photosensitive body drum surface potential detecting device 11 detecting the surface potential of a photosensitive body drum is converted into a digital, parallel data signal by an A/D converter 39 in an input interface circuit 6 and inputted into a microprocessor 5. A logical operation circuit in the microprocessor 5 compares and operates the inputted detecting data and set value read from the electrified voltage setting RAM area 31 of the non-volatile RAM 27. An electrostatically charged voltage controlling signal is outputted to an output interface circuit 17. An electrostatic charge controlling device 23 receives an analog controlling signal and generates electrostatically charged voltage according to the controlling signal in an electrostatic charger whereby the surface potential of the photosensitive body drum is held at a specified potential by the voltage. Thus, the efficiency of the maintenance operation can be improved. |
