| 摘要 |
PURPOSE: To prevent the deterioration of image quality and to extend the life of an electrifying member and the life of a cleaning member by automatically adjusting the cleaning capability of an electrifying roller according to load on a photoconductor cleaner. CONSTITUTION: The cleaning means 930 for removing residual matters from the surface of the photoconductor after transfer is provided outside an effective image area on the photoconductor surface. The device is equipped with a pretransfer detection means 916 which detects the density of a reference developed image pattern, and a post-transfer detection means 919 which detects the density of the developed image pattern on the photoconductor surface in the position where the developed image pattern has been transferred. The cleaning load on the electrification cleaning means 930 is controlled according to a transfer rate, found based on the detection output of the pretransfer detection means 916 and the detection output of the post-transfer detection means, and a deviation from a specific reference value. That is, by estimating the occurrence of an unsatisfactory cleaning of the photoconductor based on a change in photoconductor cleaning load, which accompanies a change in transfer rate, the cleaning capability of the electrifying roller 903 is appropriately controlled. |
