| 摘要 |
PROBLEM TO BE SOLVED: To provide an ultrasonic drive unit having excellent reliability, which maintains a vibration displacement of an ultrasonic vibrator always in an optimum state. SOLUTION: When supplying an ultrasonic driving signal to the ultrasonic vibrator through an impedance matching circuit, traveling wave electric power is measured by the input side of the impedance matching circuit, and the voltage level of the ultrasonic driving signal is controlled according to the peak value of the measured traveling wave electric power. COPYRIGHT: (C)2003,JPO
|
