| 摘要 |
PURPOSE:To give effective vibration stimuli to patients even at low electric power and also to prevent discontinuation of vibration even when the weight of a patient to be treated is loaded by changing over rotation the output shaft of an ultrasonic motor normal/reverse continuously to vibrate the shaft. CONSTITUTION:The circuit which drives an ultrasonic motor is connected to a high frequency voltage source 5 through an amplifier circuit 6 for one of the electrode 3 of a piezoelectric body and through the amplifier circuit 6 and a phase changing circuit 7 for the other electrode 4. The phase changing circuit 7 phase converts high frequency voltage from the voltage source 5 upon receiving signals from a normal/reverse switching circuit 8 by +90 deg. and -90 deg.. When high frequency voltage phase converted by -90 deg. is applied in the electrode 4, the ultrasonic motor rotates to the direction opposite to that when it is phase converted by +90 deg.. According to pulse signals from an oscillator, the circuit can be switched continuously at high speed into output signals corresponding to phase conversion of +90 deg. and -90 deg. and the ultrasonic motor is switched to normal and reverse rotation continuously at high speed to generate vibrations on the output shaft according to the frequency of pulse. |
