轮式直线型超声电机定子的动态设计和分析

Dynamic Design and Analysis of Wheel-Shaped Linear Ultrasonic Motor

利用非统一截面梁在正交方向上的2个同形弯曲振动模态作为工作模态,设计了一种新型直线超声电机。基于有限元理论叙述了该定子的动态设计过程,对定子驱动足位置、压电陶瓷安装位置和定子的不同夹持方式进行了仿真计算,分析了不同阶次弯曲振动模态作为定子工作模态的优缺点以及不同支撑方式对定子振动模态的影响。制造了一台原理性样机,样机定子直径为10 mm,长为55 mm,重为30 g。在驱动电压峰峰值为200 V,驱动频率为49.52 kHz,摩擦副为陶瓷摩擦材料对不锈钢的情况下,电机空载速度为374 mm/s,最大推力为13 N,推重比达到了43∶1。

A new type linear ultrasonic motor using two isomorphic bending modes was designed.The dynamic design process of the stator was detailedly described based on the finite element theory.Firstly,the location of the driving feet,the mounting location of the piezoelectric ceramics,and clamping mode of the stator were simulated and analyzed.Then,the advantages and shortcomings of the operating modes using different order bending modes and the influence of different support modes on the operating modes of the stator were analyzed.A prototype motor with a stator in length of 55 mm,a diameter of 10 mm and weight of 30 g was manufactured.In the case of the driving signal of 200 V(peak to peak) and 49.52 kHz,the motor can reach a maximum speed of 374 mm/s,a maximum thrust of 13 N and the ratio of thrust to weight 43∶1.