| 摘要 |
PURPOSE:To prevent sticking and melting of toner on the detection surface of a toner concentration detecting device and to accurately detect toner concentration. CONSTITUTION:The device is provided with a case 30 for storing developer, a spiral 33 arranged in the case 30 for stirring the developer, a developing sleeve for supplying the developer outside. The device is further provided with a toner concentration sensor 48 provided with the detection surface exposed in the case 30, a blade 50 provided on the spiral 33 for wiping the detection surface of the sensor 48, fluorine contained resin layers 49 and 53 provided on the sensor detection surface and the inside surface of the case 30 in the part with which the blade 50 comes into contact. |
