Design of the Piezoelectric Actuator with Double Driving Tips

The general operation of a piezoelectric ultrasonic resonant actuator is to convert the cyclic motion of the piezoelectric plate to a linear motion at the rotor or slider. The conventional piezoelectric ultrasonic actuator has only one stator tip to impart both the contact (normal) and driving (tangential) force on the rotor or slider. Since the rotor/slider is driven through friction, the only one stator tip design will result in lower output torques. In theory, a piezoelectric ultrasonic actuator with more stator tips will have larger output torques. However, it is difficult to design a piezoelectric actuator with multiple stator tips with synchronous cyclic motion. In this paper, the design and simulation of a novel piezoelectric actuator with multiple stator tips are presented. The accomplishment of this study is to reduce the motion difference between two different stator tips on the piezoelectric ultrasonic actuator. The Taguchi method was used to find out the optimal dimensions of the piezoelectric plate and the result shows the motion difference between two different stator tips was reduced from 19μm to 0.03μm in the X-direction and from 9μm to 0.18μm in the Y-direction.