| 摘要 |
<p>A generator for driving an ultrasonic transducer for use in ultrasonic cleaning. The generator is based on a voltage controlled oscillator (26) which drives an output circuit which includes the ultrasonic transducer (22). The output circuit has a resonant frequency, and a resonance follower (30) produces a control voltage which tunes the voltage controlled oscillator to the resonant frequency. Operating in conjunction with the automatic tuning elements is a constant power control which allows the user to set a desired power level, and monitors the actual output power by means of an output wattmeter circuit (32) to cause the actual output power to match the level selected by the user. The constant output power circuit is effective even during resonance tracking of the system, or during frequency modulation of the ultrasonic output energy.</p> |
