Patent ID: 7092650
Filing Date: 2006-08-15
Classification: G03G

Abstract:
1. A color image forming apparatus comprising: a photosensitive member having a photosensitive layer and capable of holding a plurality of developed color images; a plurality of image forming units arranged around the photosensitive member, each having a charging device, an expose device, and a developing device, each image forming unit forming one of the plurality of developed color images; a plurality of sensors to detect surface potentials of the photosensitive member, in each position between the charging device and the developing device of each of image forming unit and in a position of downstream side of a last developing device which form the last one of developed color images on the photosensitive member; an estimate device configured to estimate a predicted value of the surface potential of the photosensitive layer for one of developing devices using a first potential representing a surface potential before developing process of one of the developing devices and a second potential representing a surface potential after developing process of the other one of developing devices; and a control device configured to control the corresponding one of charging devices in the corresponding image forming unit in such a manner that the predicted value reaches to a predetermined developing reference value for the one of developing devices.