Patent ID: 7139501
Filing Date: 2006-11-21
Classification: G03G

Abstract:
1. An image forming apparatus which charges an image carrier and transfers an image formed on the image carrier to a recording medium to form an image, comprising: AC voltage generation means for generating an AC voltage; a charge member to which the AC voltage from said AC voltage generation means is applied; current detection means, connected through a capacitive member to a path which supplies a current from said AC voltage generation means to said charge member, for detecting a current value corresponding to the AC voltage flowing to the capacitive member; and control means for determining an AC voltage upon image formation on the basis of a first value which is detected by said current detection means when an AC voltage less than a discharge start voltage in the image carrier is applied to the charge member and a second value which is detected by said current detection means when an AC voltage not less than the discharge start voltage is applied to the charge members, wherein said control means calculates a discharge current on the basis of the first and second values after start of image forming and controls the AC voltage so that the calculated discharge current becomes a predetermined value upon image forming on the recording medium.