| 摘要 |
PURPOSE:To give a control to the toner concentration at a certain level, by providing the means which gives a change to the reference value to control the supply amount of the toner in accordance with the control given to the picture concentration. CONSTITUTION:When the toner concentration is reduced, the output of the sensor increases to decrease the output of the amplifier A1. The output of the comparator A2 is increased when the output of the amplifier A1 to be supplied to the reverse input terminal becomes lower than the reference voltage to be supplied to the nonreverse input terminal. Then the driver DR works to actuate the solenoid SOL, and as a result the toner is supplied. On the other hand, when the toner concentration is increased, the adverse action to the above is carried out. In such way, a certain level is maintained for the toner concentration. |
