蝶形双驱动足直线超声电机设计及实验(英文)

Design and experiment of butterfly linear ultrasonic motor with two driving tips

提出了一种新型双驱动足直线型超声电机。该电机利用联接成一体的两个振子的对称振动,在驱动足端面质点上可获得定/动子之间接触面的切向运动;利用反对称振动,可获得法向运动。同时,激励振子的对称和反对称振动在两个驱动足端面质点上可形成相同方向椭圆运动轨迹,从而驱动压在定子上的动子直线运动。采用有限元法分析了共振频率对结构参数的灵敏度,根据各灵敏度大小适当地调节了结构参数,使定子的两相共振频率基本达到一致。为了获得高速和大推力,前端盖选用硬铝材料,后端盖选用黄铜,压紧螺栓选用镀铬高强度钢材料。实验结果表明:在预压力为70N下,样机的空载速度为0.75m/s,最大推力为16N,是定子质量的22倍。

A novel butterfly linear ultrasonic motor with two driving tips is presented. It utilizes the symmetrical vibration from two vibrators bonded together as the stator to get the lateral motions of the surface points of two driving tips and uses the unsymmetrical vibration to get the normal motions. As a result, the elliptic track motions of surface points of two driving tips are formed by exciting the symmetrical and anti-symmetric vibrations synchronously and the slider compressed on the stator can be drived via friction for moving linearly. Then,the finite element model of the stator is established to calculate the frequency sensitivities to structure parameters. Based on the analysis of the frequency sensitivity, the two vibration frequencies of the stator are adjusted to the same. Duralumin and phos- phor bronze are selected for the head block and the end block respectively, and high strength chromium manganese steel bolts are used for binding the PZT elements,so that the motor can get a high output force and a high speed. Experimental results indicate that the no-load maximum speed is 0.75 m/s and the maximum output force is 16 N, which is 22 times of the stator weight.