| 摘要 |
PURPOSE: To arbitrary set the inclination of the rise of the vibration amplification of an ultrasonic vibrator transducer by resetting the amplifier output at a prescribed initial value in an oscillation stop state with an error amplifier as a proportional integrating amplifier of a prescribed time constant and starting error amplification at the time of starting oscillation. CONSTITUTION: This ultrasonic oscillator consists of a voltage control oscillator 1 of which the oscillation frequency is changed by the input signal value with the ultrasonic vibrator transducer 7 changed in power factor by a frequency as load, an output amplifier 3 which supplies electric power to the transducer 7 by amplifying the output signal of the oscillator 1, a phase difference detector 4 which detects the phase difference of the output voltage current of the amplifier 3 and the error amplifier 3 which amplifies the error between the phase difference of the output voltage current detected by the detector 4 and the set value of the phase difference. A phase locked loop is composed of the output signal of the amplifier 5 as an input signal to the oscillator 1. The output of the proportional integrating amplifier is reset at the prescribed initial value in the state of the oscillation stop with the amplifier 5 as the proportional integrating amplifier of the prescribed time constant, by which the error amplification is started concurrently with the oscillation start. |
