| 摘要 |
PURPOSE:To stabilize an image density by correcting the amt. of a toner to be replenished according to a change in the target value of the toner concn. to be controlled. CONSTITUTION:The quantity of the toner to be replenished is corrected to a change in the target value of the toner concn. to be controlled. A toner concn. sensor 25 outputs the signal from an oscillator 26 to a detector 27. This signal is inputted together with the signal corresponding to the target value of the toner concn. set by a toner concn. setter 80 respectively to the analog input port of a microcomputer 70. The output voltage of the detector 27 is compared with the target value of the toner concn. and the required quantity of the toner to be replenished is computed. A stepping motor 73 for replenishment is rotated by as much as the number of pulses corresponding thereto and the fresh toner is replenished. The stability of the image density is stabilized in such a manner and the clean images which are free from unequal densities, fogging, voids, etc., are obtd. |
