| 摘要 |
PURPOSE:To make exact correction for preventing fogging, degradation of image densities, deterioration of a developer occurring in adhesion of carriers, damage of a photoreceptor, black spots and drop-outs of images, etc., at good timing by controlling electrostatic chargerd of an image forming means on a downstream side in accordance with the results of detection of a potential detecting means on an upstream side. CONSTITUTION:The electrostatic charge potential by the first electrostatic charger CH1 is first detected by a first potential detecting sensor SE1. Consequently, the grid voltage VG2 of the second electrostatic charger CH2 is lowered by a certain prescribed value than heretofore if the detected voltage is higher than the upper limit value of the electrostatic charge potential. Namely, the electrostatic charge potential by the second electrostatic charger CH2 is made lower than heretofore. The grid voltage VG2 of the second electrostatic charger CH2 is raised by the certain prescribed value than heretofore if the detected value is below the lower limit value of the electrostatic charge potential. Namely, the electrostatic charge potential by the second electrostatic charger CH2 is made higher than heretofore. |
