| 摘要 |
PURPOSE: To adjust drive signals of an ultrasonic vibrator while reducing energy loss due to heat according to switching operation utilizing pulse width modulation. CONSTITUTION: A device for driving ultrasonic vibrators 16 and 20 for exciting longitudinal vibration and flex vibration at an elastic body and generating ultrasonic elliptical vibration with an electromechanical energy transducer as a drive source is provided with a modulation signal generation circuit 30 for generating a modulation signal in analog waveform for driving the ultrasonic vibrators 16 and 20, a carrier signal generation circuit for generating a carrier signal with a frequency higher than the modulation signal generation circuit 30, and a modulation circuit 31 for performing the pulse width modulation of the carrier signal by a modulation signal. Therefore, a switching circuit 32 for outputting a drive signal for ultrasonic vibrators 16 and 20 by performing switching with the modulation output signal of the modulation circuit 31 and a filter circuit by eliminating the frequency component of the carrier signal from the drive signal from the switching circuit 32 and applying it to the ultrasonic vibrator are provided. |
