A peripherally bolted torsional Langevin vibrator with large diameter.

To fabricate a bolt-clamped large diameter Langevin torsional vibrator as designed is usually difficult. A torsional vibrator tightened with an outside bolt is proposed in which the designed characteristics in the resonant vibration of the normal mode is achieved. A torsional vibrator 80 millimeters in diameter with a calculated resonant frequency of 28kHz has been fabricated. The resonant frequency of the torsional vibrator is 26.1kHz, the quality factor is 890 and the maximum angular velocity is 4.1 rad/s. It is confirmed that the vibration characteristics obtained with the externally-bolted transducer are improved compared with the torsional transducer tightened with an inside bolt.