| 摘要 |
PURPOSE:To enable only one of photosensitive layers to be operated and make possible both monochromatic copying and color copying by superposedly sensitizing the respective photosensitive layers separately formed for each color in performing two color copying and making selective use of two power transmission systems. CONSTITUTION:When monochromatic operation is selected, a clutch 26 engages, causing a photosensitive drum 1 to be driven counterclockwise via first power transmission system. In this case, a one-way clutch 16 acts in the disengaging direction, prohibiting turning of a driven pulley 18 and causing a photosensitive sheet 2 to be detained in the illustrated position. During one turning of the photosensitive drum 1, the monochromatic recording operation takes place. When two- color operation is selected, the clutch 26 is disengaged, 27 is engaged. This causes the photosensitive drum 1 to be driven by the second driving system by way of a timing belt 17, driven pulley 18 and one-way clutch. At this time, the photosensitive sheet 2 mounted to a timing belt 17 also turns integrally with the outside peripheral surface of the photosensitive drum 1, thus during one turning the recording operation of two-color visible images takes place. |
