| 摘要 |
PURPOSE:To reduce a malfunction, to improve the detection precision and to prevent the wear or the like of a developing blade by moving a member in accordance with the toner level to detect the toner end. CONSTITUTION:A revolver type developing device 1 is provided with a means 2 which detects whether a surface 15 of toner 14 in each developing device 11 is above a specific point 16 in the developing device 11 or not, and the toner end is decided when the detecting means 2 detects that the toner surface 15 is always below said point in the course where the developing device 11 is turned to a developing position from its adjacent position. Thus, the detection precision is improved and the wear of a developing blade 13 or the like is reduced, and toner scattering or the like has no influences upon this detection. |
