| 摘要 |
PURPOSE:To prevent the entry of toner into the contact areas between spacer members and quide faces for these by providing torus grooves and scarper blades on the outside circumferential surface of a donor drum. CONSTITUTION:Torus grooves 1a are provided at the boundary parts of the image forming effective region 1b which carries the toner in the central region on the outside circumferential surface of donor drum 1 and the quide faces 1c of the spacer members 28 which maintain the spacing between the donor drum 1 and recording electorode 2 constant on the right and left side end parts, and the skirt parts of spacer member brackets 26 are engaged by leaving a small spacing. Also scraper blades 30 are disposed to the guide faces 1c. Then, even if the toner in the image forming effective region 1b tries to enter the contact region between the guide face 1c and spacer member 28, it is blocked by the torus grooves 1a and even if it deposits on the guide faces 1c, it is scraped away from the guide faces 1c by the scraper blades 30 just before the contact areas. |
