| 摘要 |
PURPOSE:To properly detect the presence or absence of a developer in a developing unit of a process cartridge by interlocking either a light emitting part or a light receiving part with the maintenance action of a device main body and cleaning part. CONSTITUTION:When the process cartridge 10 is removed from the fitting part 2 of the device main body for replacement, cleaning members 32a and 33a expand in fitting holes 2a and 2b because the inner parts 32a and 33a of cleaning members 32 and 33 pass through the fitting holes 2a and 2b. The process cartridge rubs the outer surface of the light emitting part 27a and the light receiving part 27b of a toner detecting means 27, and eventually cleans the outer surfaces of the light emitting part 27 and light receiving part 27b. Consequently, the light emitting part 27a and the light receiving part 28b can be maintained free of foreign matters such as toner and dust, and accordingly the presence or absence of a developer can be detected accurately. |
