| 摘要 |
PURPOSE:To improve detection accuracy by sampling the detection output of a toner sensor based on a detection cycle acynchronous with the rotation cycle of an agitator. CONSTITUTION:A detection signal outputted from a piezoelectric toner sensor 7 is sampled in a prescribed detection cycle, and the level of the sampled detection signal is identified based on a threshold value; the identified result, that is, identification data on whether toner 2 remains or not is sequentially stored in a memory 13. As it does so, the prescribed detection cycle is set to be asynchronous with the rotation cycle of the agitator 5 which agitates the toner 2. Therefore, only when a cleaner 6 rubs the detection surface of the piezoelectric toner sensor 7 as the agitator 5 rotates, the sampling of the detection signal of the piezoelectric toner sensor 7 is not repeated. |
