| 摘要 |
PURPOSE:To accurately maintain the toner concentration of the image recorder even when carrier of two component developer is changed with a lapse of time or when there is variation in sensitivity of the toner concentration sensor. CONSTITUTION:A compensation value m of sensitivity so that the variation quantity of the output voltage Vo of a toner concentration sensor against the variation quantity of control voltage Vc of a toner concentration sensor 28 is made equivalent to a value set beforehand and a compensation value Vc against variation due to the lapse of time are calculated and read in. Everytime a sumed up recorded pieces of paper n is increased by a specified number of pieces, control voltage Vc is varied based on the compensation value m and Vc. |
