Studies On An Explosion-proof Linear Ultrasonic Motor

This project is derived from Natural Science Foundation of China Name of Fundamental Research of Explosion-proof Piezoelectric Motor (No.50807048).Ultrasonic motor (USM), which can also be called piezoelectric motor, utilizes the vibration of the elastic body (stator) in the ultrasonic frequency band and the converse piezoelectric effect of piezoelectric materials. A linear ultrasonic motor (LUSM) is an important type of USM. Besides the common characteristics of rotary USM, LUSM also possesses the following advantages:the capability of direct and straight drive, a simple structure, a flexible design, allowing easy miniaturization. It has been widely used in many fields such as precision instruments, astronautics, medical field, automobile and micro-robot. But there are some problems about LUSM, and no research of LUSM being used in the explosive atmosphere.In order to enhancing output characteristics, efficiency and applying to the explosive atmosphere, this dissertation has been studied out an explosion-proof linear ultrasonic motor. The specific contributions of this work are as follows.1. The analysis of explosion-proof LUSM about broad application prospect and background is presented. It is pointed out the significant and problems of explosion-proof LUSM.2. Based on the operating principles of LUSM and the excitation process of operating vibration modes, it is demonstrated the elliptical movement of driving foot and pointed out some design requirements of LUSM.3. The main structural sizes which effect on the modal frequency of stator has been analyzed and determined by use of ANSYS software. The assembly drawing and power supply of explosion-proof enclosure of explosion-proof LUSM have been designed.4. The two unequal modal frequencies have been resolved by combining the structure perturbation and finite element method. Through the harmonic response analysis of the stator, the optimal modal frequency has been found. From the transient analysis, the response time of stator is around0.16s.5. Three prototype stator of LUSM have been manufactured. After adjusting of two modal frequencies, the difference of them is only70Hz. From the experimental result, the maximum speed of LUSM without load is46mm/s. Through the explosion-proof test of manufactured power supply enclosure, it is proved that the explosion-proof enclosure is qualified.