| 摘要 |
PROBLEM TO BE SOLVED: To make jam processing smooth without damaging the surface of a photoreceptor drum by adopting such a constitution that devices being in contact with or adjacent to the periphery of the drum are removed after the drum is stopped, so as to freely rotate it forward and backward. SOLUTION: When a paper sheet is stuck to the drum 1 or enters a photoreceptor drum unit along the drum 1 for some reason, in a copying process, the fact is detected by a paper entrance detecting sensor 10 in the vicinity of an entrance in the photoreceptor drum unit. When the detection signal is received, the rotation of the drum 1 is immediately stopped. After the stopping of the drum 1 is confirmed, the devices being in contact with or adjacent to the periphery of the drum 1, for instance, a drum cleaner 7 for removing toner remaining on the drum 1 and developing units 4a-4d for developing a latent image on the surface of the charged drum 1 are removed to secure some gap around the drum 1. Further, a gear is released so that the drum 1 can be freely rotated forward and backward, to easily remove the paper. |
