TRIAL PRODUCTION OF AN ULTRASONIC MOTOR USING LONGITUDINAL AND TORSIONAL VIBRATIONS OF A ROD VIBRATOR DRIVEN BY PIEZOCERAMIC PLATES INSERTED IN ITS AXIAL DIRECTION

This paper deals with a rod-type ultrasonic motor using the first long itudinal and second torsional vibration modes of a rod vibrator driven by piezo-ceramic plates inserted in its axial direction; that is, met al blocks of rod vibrator are made as a quonset hut type. This constru ction is aimed at being suitable for miniaturization of a rod-type ult rasonic motor. Piezo-ceramics to excite longitudinal and torsional vib rations are rectangular in shape so that production of the motor is ea sy. By this construction of the motor, the mechanical strength of bond ing the stator vibrator of motor is also made possible, because of the wide splicing surface of the metal blocks of the stater vibrator. In this paper, the authors investigate experimentally a prototype motor t o confirm its operation and performance. It was found that the longitu dinal and torsional mode vibrator newly proposed by the authors functi oned as a stater vibrator for an ultrasonic motor, and the method of c onstruction was also effective for the practical use of the motor.