| 摘要 |
PURPOSE:To easily write different information at an optional position by composing an erasing means of a movable shutter which cuts off the optical path of exposure for a document and a pulse motor which positions the movable shutter at a specific position of an image carrier. CONSTITUTION:A photosensitive drum 10 is rotated as shown by an arrow (b) to scan and form a document image on the drum 10 with incident light Bi and a 2nd pulse motor 204 is driven right before the subscanning-directional front end of the part of the document image to be erased or written reaches an exposure position Ph. Then a ring lever 206 is rotated. Consequently, the shutter 207 moves as shown by an arrow (d) to cut off the light Bi. At this time, the length of the shutter 207 in the moving direction is long enough to cut off the entire surface in the width direction at the exposure position Ph. Therefore, charges on the drum 10 at the part are not erased and another piece of information can be written with laser beam light 110 positioned on the rotating-directional side of the drum 10 as compared with the front end of the shutter 207. |
