ULTRASONIC VIBRATOR

PROBLEM TO BE SOLVED: To provide an ultrasonic vibrator capable of accurately measuring propagation time of ultrasonic vibration.SOLUTION: A carbon fiber composite material 2 side of an ultrasonic vibrator 1 is made to contact to a side surface of a stainless vessel 6 by way of a silicon-based grease which is a contact medium. Here, a center axis position of the ultrasonic vibrator 1 is about 40 mm higher than a bottom surface of the stainless vessel 6. Then, a piezoelectric element 3 of the ultrasonic vibrator 1 is applied with an application voltage being sin wave pulse of 2 MHz, 10 Vp-p. As a result, the ultrasonic wave is propagated to the carbon fiber composite material 2, the stainless vessel 6, and pure water 9, and the most of it is reflected on the opposite inside surface of the stainless vessel 6 and then propagated to the pure water 9 again, and to the stainless, the carbon fiber composite material 2, and the piezoelectric element 3. The ultrasonic vibration propagated to the piezoelectric element 3 causes voltage at the piezoelectric element 3, thereby obtaining reception waveform.