Transducer for linear motor and its application to large diameter ultrasonic motor

摘要

We studied on a large torque and high efficiency ultrasonic motor. At first, we fabricated an ultrasonic motor with a transducer and a small rotor. The transducer consists of two sandwich-type vibrators. The diameter of the rotor was 0.063m. The maximum efficiency of the motor was 53% at the rotation speed of 11 rad/sec and the load torque of 1.7N·m. Next, we made a large diameter ultrasonic motor with the same three transducers and a large rotor. The rotor was the inner ring of a cross-roller bearing. The bearing bore diameter was 0.34m. We confirmed composition of torques of the three transducers. The no-load speed and the maximum torque were 1.4rad/sec and 8.3N·m.