Device for controlling charge area of photoreceptor

摘要

A device for controlling the charge area of a photoreceptor comprising a detector for detecting the length of a sheet of copying paper, another detector for detecting the length of an image projected area of the photoreceptor, a selecting device for selecting the shorter one between the detected length of the copying paper sheet and that of the image projected area by comparing them with each other, and controls for controlling the charging time of the main charger so as to charge the photoreceptor to an area corresponding to a length selected by the selecting device, whereby the charge area of the photoreceptor is properly controlled so as to correspond to an area necessary to be transferred, even when the length of the image projected area on the photoreceptor differs from that of the copying paper sheet.