Patent ID: 7865097
Filing Date: 2011-01-04
Classification: G03G

Abstract:
1. An image forming apparatus comprising: a photosensitive member; a charger configured to charge said photosensitive member; a voltage applying unit configured to apply a voltage to said charger; a current detection unit configured to detect a current that flows through said charger upon application of the voltage by said voltage applying unit; and a control unit configured to control said voltage applying unit based on a detection result of said current detection unit, wherein when a plurality of images are to be formed continuously, said control unit controls said voltage applying unit to apply a voltage of a first value that does not cause discharging by said charger during a first period in which a first non-image-forming area is located on a charging part where said photosensitive member is charged by said charger, to apply a voltage of a second value that does not cause discharging during a second period in which a second non-image-forming area is located on the charging part, to apply a voltage of a third value that causes discharging during a third period in which a third non-image-forming area is located on the charging part, and to apply a voltage of a fourth value that causes discharging during a fourth period in which a fourth non-image-forming area is located on the charging part, and image-forming areas exist between the neighboring first to fourth non-image-forming areas, and wherein said control unit determines a voltage value to be applied from said voltage applying unit to said charger during a period in which the image-forming area where an image is formed is located on the charging part, based on the voltages of the first to fourth values, and the detection results of said current detection unit during the first to fourth periods.