摘要 |
<p>An apparatus and method for ultrasonic cleaning is disclosed in which a transducer (35) in a liquid bath is driven by electronic circuitry causing rapid change of frequency to limit development of high concentration for any significant period of time. The electronic circuitry uses two field effect transistors (19 and 20) driving a square wave into an inductor (31) and capacitor (32) in series with a transformer inductor (33) which is coupled in parallel to the transducer (35) the inductor (31) and capacitor (32) and the transformer inductor (33) which is coupled in parallel to the transducer (35) being selected to be resonant at a mean driving frequency.</p> |