关键词: 直线超声电动机, 结构刚度, 有限元分析, 弯曲模态, 结构动力学

Abstract: In order to improve the structural stiffness of the stator of the existing threaded linear ultrasonic motor, reduce the resonant frequency and increase the output force of the motor, the stator structure of the motor was designed and experimental research was carried out. The motor was composed of a slotted stator matrix, a threaded motor and four pieces of piezoelectric ceramics, which were driven by two third-order in-plane bending modes of the stator. The finite element software was used to analyze the influence of the slot width of the stator internal thread on the modal frequency, and the structural dynamics analysis was carried out to obtain the displacement response and motion trajectory of the stator driving point. Trial-produced a prototype and built a test platform for mechanical characteristics. The experimental results show that the motor can run in a wide frequency range, the best working frequency of the motor is 75. 2 kHz, the maximum speed is 0. 59 mm / s, and the maximum output force is 1. 4 N, which is 31. 1% and 16. 7% higher than that before optimization.

Key words: linear ultrasonic motor, structural stiffness, finite element analysis, bending mode, structural dynamics