| 摘要 |
<p>An ultrasonic operating apparatus comprising a hand piece containing an ultrasonic vibrator generating ultrasonic vibration, a probe connected with the hand piece and transmitting the ultrasonic vibration, a drive signal generating means for generating a first drive signal driving the ultrasonic vibrator and a second drive signal having an output level different from that of the first drive signal and outputting them to the ultrasonic vibrator, a means for detecting the output current and the output voltage of the second drive signal to the ultrasonic vibrator, and a means for controlling the operation of the drive signal generating means according to the phase difference between the output voltage and the current of the second drive signal and judging the operating state of the probe or hand piece on the basis of whether the resonance frequency at which the phase difference between the output voltage and the output current is substantially equalized can be detected within a predetermined range or not.</p> |
