| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus for achieving durability improvement of an image carrier by preventing the occurrence of a leak black point to the image carrier. <P>SOLUTION: The image forming apparatus provided with a transfer roller 24 for transferring toner images formed on a photoreceptor drum (image carrier) 21 on paper (transfer material) S is provided with a contact pressure variable means 6 (a transfer gap roller 34, cams 36, a motor 37, a driver 38, a control means 38 and the like) for varying a contact pressure to the photoreceptor drum 21 of the transfer roller 24, based on size information of a longitudinal direction of the paper S detected previously. Specifically, the smaller the size of the longitudinal direction of the paper S is, the larger the contact pressure to the photoreceptor drum 21 of the transfer roller 24 is, in the contact pressure variable means. <P>COPYRIGHT: (C)2008,JPO&INPIT |
