| 摘要 |
PURPOSE:To obtain the uniform quality of copies by installing a means for controlling a developing speed so that the higher an electric potential is, the lower the speed is made, according to the surface potential of a photosensitive body detected by an electric potential detection means. CONSTITUTION:A detected output which shows the surface potential of the photosensitive drum 1 detected by the surface potential sensor 4 is converted into a digital signal in an A/D converter 21 and transmitted to a microcomputer 22. The microcomputer 22 arithmetically processes the transmitted digital signal and outputs the arithmetically processed results and it stores an arithmetical formula which shows the relation between the surface potential and the developing speed as a program. When the surface potential tends to be high and copying density tends to be thick the developing speed is lower so as to keep the copying density constant. Thus, the lowering of the quality of copies; the copying density just after quiescence becomes thick or the degree of density changes because of the variance, etc., of a quiescent period and the characteristic of the photosensitive body, can be removed. |
