| 摘要 |
PURPOSE:To maintain the charge voltage of a photoreceptor constant and to carry out superior development, by measuring developing current, feeding back this current value to a charger controller, and controlling the charge voltage so as to keep the feedback value constant. CONSTITUTION:On anticlockwise rotating photosensitive drum 1, corona discharge of electrode 2 uniformly charges its surface, a given optical system scans an original at a speed in a constant ratio to that of drum 1 rotation, and the original light image illuminates drum 1 through window 3 of the system to form an electrostatic latent image on the photoreceptor. The image is developed in developing unit 4, and moved to transfer unit 5. The cylinder of developing roller 6 is grounded through current measuring device 10, and the developing current value measured is sent to charge controller 12 which controls the output voltage to supply it to charger 2 in the direction reverse to to that of developping current change, permitting compensation so as to maintain the charge voltage of the photoreceptor constant. |
