| 摘要 |
PURPOSE:To improve reliability and reduce costs by the simple constitution consisting of removing the carrier components on the surface of a rotary sleeve with a scraper, detecting the amount of the toner remained on the surface of the rotary sleeve and controlling the toner density of the developer with said detected amount as density information. CONSTITUTION:A scraper 13 which peels the developer (a) receiving no more influence of a magnet 8 located in the upper part by having passed through a development area 12 and guides the same onto an impeller 11 is provided in the upper rear side of a magnet roller 5, and further, an optical density detector 18 is provided below the scraper 13, by which the density of a residual toner sticking area 19 where only the residual toner a'' separated from the carriers on the surface of a rotary sleeve 7 sticks is detected and is fed as density information to a density control circuit 25 which produces a replenishing signal 26 when the density is low, whereby replenishing of the toner a' is accomplished. |
