DESIGN OF A HYBRID TRANSDUCER TYPE ULTRASONIC MOTOR

This paper presents a design method of a hybrid transducer-type ultrasonic motor (HTUSM) aimed at practical uses of the motor. We introduce a simple equivalent circuit that expresses the unique operation mechanism of the hybrid transducer-type motor. The numerical simulation based on the model enables us to predict the motor characteristics such as the maximum torque and the no-load revolution speed. In addition, for the purpose of efficient design and physical interpretation of the phenomena, we discuss analytically the maximum torque of a special case and develop two design charts for the prediction of the no-load speed of the motor.