| 摘要 |
PURPOSE:To permit continuation of normal copying even in the event of a trouble in a control system in an electrophotographic copier which controls electrostatic charging, exposure and developing in accordance with the measured value of the potential on the surface of aphotosensitive drum by releasing the controlling by the command from the outside. CONSTITUTION:The potential on the surface 1 of a photosensitive drum is measured with a surface potential sensor 7, and in accordance with the result thereof, the quantity of an exposure lamp, the voltage to be supplied to an electrostatic charger, developing bias, etc. are controlled so that the best image is obtained. If said control is infeasible on account of a trouble in the sensor 7, etc., the normal copying operation cannot be made and therefore a command is given from the outside to a microcomputer 15 so as to skip the control routines of exposure, electrostatic charging and developing discretely, and the copying operation is continued at the standard quantity of light, charging quantity and developing bias value. |
