Ultrasonic piezoelectric vibrator coupling - uses contactless electrodes supplying alternating current at resonant frequency

摘要

The ultrasonic transducer consists of a cylindrical piezo ceramic body which is mounted in a holder by a clamp around the centre. The transducer is energised by an alternating current of a frequency equal to that of the transducer resonant frequency. The supply electrodes consists of rings placed concentrically around but out of contact with the ends of the cylindrical body. In an alternative form the electrodes are flat metal panels placed parallel and close to the cylinder ends. One panel has an aperture for the transmission of the ultrasonic waves. The design uses capacitative coupling which at the frequency used gives good energy transfer.