| 摘要 |
PURPOSE:To keep toner concentration constant by deciding the toner supply amount of a toner supply means based on the calculated variation of the toner concentration and the detected toner concentration. CONSTITUTION:Magnetic sensors 28a and 28b detecting the toner concentration output a voltage value in accordance with the toner concentration by using a phenomenon that magnetic permeability becomes lower in the case the toner is more and the magnetic permeability becomes higher in the case the toner is less. Then, toner supplying time is decided by using fuzzy inference based on the absolute value of the toner concentration(the output voltage of the magnetic sensor 28a) and the variation of the toner concentration(the difference of the output voltage between the magnetic sensors 28a and 28b) so that the toner concentration in a developing unit 18 may be a fixed value, that means, the output voltage of the sensors 28a and 28b may be converged to be a specified value. When a toner supply roller 32 is rotated by driving a toner supply motor, the toner in a toner box 30 drops in the developing unit 18, thereby supplying the toner 20 to the developing unit 18. |
