Some constructions and characteristics of rod-type piezoelectric ultrasonic motors using longitudinal and torsional vibrations

Ultrasonic motors using longitudinal and torsional motions of rod vibrators have previously been proposed. Several motor constructions, whose forms are different from the previous ones, are proposed and their characteristics are experimentally examined in order to develop the ultrasonic motors of this type; that is, they are expected to have much different uses, according to how their forms are modified. Two groups of motor are dealt with: one contains motors basically suited to the relatively high torque of 2-3 kgf-cm and the other contains motors for small or medium torque below about 1.0 kgf-cm. As the result, operational characteristics of motors are totally revealed. These are useful in developing the rod type ultrasonic motors and in their practical applications.