| 摘要 |
<p>A controllable frequency ultrasonic signal generator for driving an ultrasonic transducer via a switching type output circuit for the efficient transfer of energy thereto. The signal generator includes a phase lock loop feedback control for locking the operation of the oscillator to the resonant frequency of the transducer for following variations in transducer resonant frequency due to loading changes, temperature changes, tool tip variations, and the like.</p> |
