| 摘要 |
PURPOSE:To accurately confirm the residual quantity of developer and the replacement timing of a process cartridge by providing a passing means through which light for detecting the residual quantity of the developer can be transmitted on a used developer containing part. CONSTITUTION:Every time a stirring rod 20a is rotated, the surface of a residur detecting window 2 is rubbed with a stirring sheet member 21a so that toner (t) is wiped away. The toner (t) is replenished to the inside of a developing device 18 by the stirring rod 20a and the stirring is repeated. As a result, the toner (t) on the surface of the residur detecting window 2 is used up and the light emitted from a light emitting part 3 is projected on a light receiving part 4 positioned while facing the residue detecting window 2, whereby a voltage is generated in the light receiving part 4. Therefore, the voltage level of the light receiving part 4 is changed according to the way the toner (t) sticks on the surface of the residur detecting window 2. The value of the voltage level is read so as to detect the presence or absence of the toner (t). Thus, the residur quantity of the developer in a developer container and the replacement time of the process cartridge can be accurately recognized. |
