| 摘要 |
PROBLEM TO BE SOLVED: To make functions of the developer quantity detection and waste toner full tank detection for plural developing units possible to be served by one sensor. SOLUTION: This device is constituted so that a waste toner container 150 is pushed up by the force of spring 152 when the waste toner therein is lessened and lightened, and light beams 162 emitted from a light emitting section 160 in the toner end sensor, are allowed to pass through a hole 151 of the waste toner container 150 and to reach the light receiving section 161. Then, at the time the waste toner container 150 becomes heavy by the increase of the waste toner, the spring 152 contracts, and when the waste toner container 150 lowers downward, the light beams 162 emitted from the light emitting section 160, are made impossible to pass through the hole 151 of the waste toner container, and impossible to reach the light receiving section 161. |
