| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent outflow of toner and carrier to the surface of a photoreceptor when detecting discharge start voltage. <P>SOLUTION: The image forming apparatus performs charging control, such that surface potential of the photoreceptor 1 when applying two AC peak-to-peak voltages: Vpp1 and Vpp2 which are equal to or smaller than the double the discharge start voltage, and AC peak-to-peak voltage Vpp3 which is more than the double the discharge start voltage to a charging means 2 is detected by a detection means 4, to thereby specify the discharge start voltage (Vth); and the peak-to-peak voltage is set to the vicinity of the discharge start voltage (2Vth) that is double, wherein the surface potential of the photoreceptor 1, when applying Vpp1 and Vpp2 is detected and then bias to make the surface potential of the photoreceptor 1 become a predetermined value is applied to a developing means 5, according to the result of detection. <P>COPYRIGHT: (C)2008,JPO&INPIT |
