| 摘要 |
PURPOSE:To display the remaining quantity of tonor in stages or continuously by arranging a resistor inside a tonor tank, converting the change of the resistance value of the resistor into voltage and current and comparing the resistance value with the standard value. CONSTITUTION:A U-shaped or V-shaped transistor 11 i inserted vertically into the tonor tank 17 of a magnet dry developer from an insulated blacket 12. Both ends of the resistor 11 are connected to the external electric circuit through a lead line 14. Since the resistance of the tonor itself is low, about 3X10<3>OMEGAcm-3X10<4>OMEGAcm, the resistance value measured on the basis of the quantity of tonor is changed. The change of the resistance value is converted into voltage, current by a resistance value-voltage current converting circuit, the output is compared with the standard value in a comparator and the compared result is displayed through a display circuit. |
