| 摘要 |
PURPOSE:To transfer a toner image onto a transfer paper effectively, by giving two degrees of freedom and the elastic force of a spring to a transfer roll to press the transfer roll to a photosensitive drum and obtaining a uniform transfer pressure in all regions of the transfer roll to prevent the unevenness of transfer of the toner image. CONSTITUTION:When a copying device is not operated, a transfer roll 16 is separated from a photosensitive drum 11, and a frame 18 is turned around a supporting shaft 14 clockwise and is stopped by a stopper. At this time, the first supporting material 17 is turned around a supporting shaft 18 counterclockwise by the elastic force of a spring 21, and a part (a) of the first supporting material 17 is brought into contact with a part (b) of a frame 13 and is stopped. When the copying device is operated, that is, when the copy is started, the frame 13 is turned around the supporting shaft 14 counterclockwise and is brought into contact with a stopper 22 fixed to the copying device body frame 13 and is stopped. At this time, though the transfer roll 16 is pressed to the photosensitive drum 11 by the elastic force of a spring 21, the distribution of contact pressure is uniform because the transfer roll 16 is supported by the first and the second supporting materials 17 and 19 having two degrees of freedom shown by arrows B and C. |
