| 摘要 |
PURPOSE:To shortcircuit a resistor exactly by a method wherein a part of the output of a pulse generating inverter is taken out and rectified and the rectified voltage is amplified so that the resistor provided on the input power source side of the pulse generating inverter is shortcircuited simultaneously upon the start of oscillation of the inverter. CONSTITUTION:An amplifier 20 is inserted in the circuit of tertiary winding 63 of a transformer 6, that is, the control circuit of an SCR4. The signal produced in tertiary winding 63 by the pulse oscillation of an inverter 7 is rectified and smoothed by a diode 12 and a condenser 13. The amplifier 20 amplifies the rectified signal to a fixed voltage regardless of the magnitude of the DC voltage caused by the pulse width, sends it to the control element of the SCR4, performs exact operation, and shortcircuits a resistor 3 by the conduction of the SCR4. |
