Patent ID: 6498907
Filing Date: 2002-12-24
Classification: G03G

Abstract:
An image forming apparatus comprising:an image bearing member for bearing a developer image; transferring means for electrostatically transferring said developer image onto a transfer material; a power supply for applying a voltage to said transferring means; electric current detecting means for detecting a value of an electric current which flows to said transferring means when the voltage is applied from said power supply to said transferring means; and controlling means for controlling an output of said power supply by varying the voltage applied to said transferring means by a predetermined voltage quantity in such a manner that the value of the electric current detected by said electric current detecting means becomes a predetermined target electric current value, wherein the predetermined voltage quantity is variable, and impedance is calculated based on a value of the electric current when a predetermined voltage is applied to said transferring means and a value of the predetermined voltage, and the predetermined voltage quantity is determined based on the impedance.