| 摘要 |
PURPOSE:To prevent toner from being unnecessarily leaked from the side plate part of a developing part case fitted into the developing sleeve of a developing device. CONSTITUTION:The developing device is constituted to rotatably fit a cylindrical developing sleeve 32 into the opening part 31 of the developing part case 30, semicircular notched stepped parts 35 are formed on the left and right side plate 30a of the opening part 31 in the developing part case 30 and projections 36 are formed on the connecting corner parts of each notched stepped part 35 with the end surfaces of the left and right side plates 30a as well. Sealing materials 34 disposed so as to abut on roughly semicircular parts on both circumferential end parts of the developing sleeve 32 are arranged along the semicircumferential end faces of the notched stepped parts 35 from the end surfaces of the left and right side plates via the projections 36. Thus, a gap from which the toner leaks, is not formed with respect to the surface of the sealing material 34 in a place curved outward in the radial direction of the developing sleeve 32 in the place of the projection 36. |
