| 摘要 |
<p>PURPOSE:To improve the responsiveness in the control for a heater by installing a primary delaying circuit for delaying the detection output signal of the electric power supplied into a heater by the time constant of the heater. CONSTITUTION:A prescribed voltage is supplied to a differential amplifier 7 through a variable resistor 6 from an electric power source 5. The time constant of a primary delaying circuit 4 is set at the thermal time constant of a heater RH, and through the terminal voltage of a capacitor 4 rises with the time constant, the operation amplifier 7 is in a saturated state up to the time when the terminal voltage of the condenser 3 reaches a certain voltage, and the output voltage does not vary. Accordingly, the period voltage VH becomes max., and the voltage is squre-amplifed by a multiplicator 1, and supplied to the circuit 4. When the voltage of the capacitor 3 rises to a certain value, the differential amplifier 7 separates from a saturation valve region, and operates in a linear region, and also the output voltage reduces according to the time constant of the circuit 4. Accordingly, on the starting-up, a high voltage is supplied to the heater RH, and heating is carried out speedly, and after the heating is completed, the voltage is maintained at a prescribed value.</p> |
