| 摘要 |
PURPOSE:To prevent powder toner from flying to guide faces and roller portions by disposing torus-form flange members at the boundary between the effective image forming regions and guide faces of a donor drum. CONSTITUTION:The central portion between the two guide faces 1a and 1a of a donor drum 1 is the effective image forming region 1b and torus-grooves 1c are formed at the boundary parts between said effective image forming region 1b and guide faces 1a. Torus-form flange members 29 are mounted to the respective effective image forming regions 1b of the torus grooves 1c, exist between the above mentioned effective image forming regions 1b are guide faces 1a respectively and are shielding both. Hence, even if the toner of the effective image forming region 1b of the donor drum 1 fly, it may be prevented from flying to the contact regions between the rollers 28 and guide faces 1b. If grooves 30 or the like of V-form in section are provided to the end faced on the side of the effective image forming region 1b of the torus-form flange members 29, the foregoing flying may be more surely prevented. |
