| 摘要 |
PURPOSE:To prevent images from being stained when formed continuously by performing reading or exposing operation within a range limited with an image effective signal generated by a 1st or 2nd CPU. CONSTITUTION:At least the 1st CPU 2 or 2nd CPU 11 generates the image effective signal V-VALID1 or V-VALID2 whose range is smaller than the length of transfer paper in the rotational direction of a drum and the reading or exposing operation is carried out within the range limited with the image effective signal. Consequently, when a copying machine which performs reversal development is used, no toner sticks on a part where no image is written on the drum, so no toner sticks on the end part of the transfer paper. Therefore, the upper fixing roll Ru of a fixation part is not stained with toner and when continuous image formation is carried out, the images are prevented from being stained. |
