| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an ultrasonic motor improving a vibrating efficiency by highly efficiently transmitting the vibration of an electromechanical conversion element to a member to be driven. <P>SOLUTION: The ultrasonic motor 1 is equipped with: a bar-like elastic body 12 having a groove portion 14; a pair of stacked piezoelectric elements 18 having both ends held on the bar-like elastic body 12, disposed on a front surface 12a and a rear surface 12b in a state of having an acute angle as an angle between the displacement direction and the longitudinal direction of the bar-like elastic body 12 and arranged on the bar-like elastic body 12 so as to be inclined in the opposite direction to each other when viewed face to face in the longitudinal direction of the bar-like elastic body 12; and a frictional piece 26 bonded to the front end of the bar-like elastic body 12. In the ultrasonic motor 1, alternating voltages different in phase are applied to the pair of stacked piezoelectric elements 18 respectively, thereby simultaneously exciting longitudinal vibration and torsional vibration to cause the frictional piece 26 to excite an ultrasonic elliptic movement. The ultrasonic motor 1 has an equalizing section 24 for equalizing high rigidity and low rigidity generated near the frictional piece 26 when the frictional piece 26 excites the ultrasonic elliptic movement. <P>COPYRIGHT: (C)2011,JPO&INPIT |
