| 摘要 |
PURPOSE:To erase an unnecessary image by providing an erasing lamp in front of a developing device, and controlling its illuminating part with a pair of light shading sheets moving in the axial direction of a photosensitive body in a parallel plane, and opposite to each other. CONSTITUTION:When an original 1 of size B4 is copied by contracting it to a paper of size A4, a contraction instructing signal is fed to a controller 26, a control signal drives a drive motor 24, light shading sheets 25a, 25b applied to the surface of an endless belt 21 are adjusted so as to allow an erasing lamp 20 to illuminate the position of an electrostatic latent image formed on a photosensitive drum 9 corresponding to the 2-3mm. widths of both side ends of an A4 sized copying paper. The light of the lamp 20 is intercepted with the sheets 25a, 25b and does not reach the effective area region (e) on the drum 9. On the other hand, since the other part of the belt 21 transmits light, the light reaches the drum 9 to erase a latent image at that part and form an image erased region F. As a result, an unnecessary image can be erased in accordance with optional magnifications. |
