【摘要】 圆盘式压电马达的定子被激发出行波后,用于驱动转子的摩擦界面上质点运动为三维斜椭圆,其中的径向分量将引起纯粹的摩擦损耗而导致传动效率降低。分析了圆盘型压电马达定子振动响应的运动学特性,提出定子齿可等效为基体加上附属齿形的复合结构振动;利用动态子结构和有限元法建立了考虑齿槽的定子振动方程,分析了定子齿驱动表面质点的运动特性,指出通过齿形参数设计可以减少径向运动分量的比例;以某特定圆盘压电马达定子为例,以接触界面的传动效率作为优化目标进行定子齿参数的设计,通过迭代得到了能够获得较好输出效率的参数组;通过数值仿真分析了最优参数下压电马达的输出特性,并与其他参数组下的输出特性进行分析和比较;最后加工了特定几组参数的中空型压电马达样机,验证了摩擦界面上径向滑动造成的损耗与定子齿形参数有关,在同样激励条件下的确可在最优参数组获得较好的输出效率。更多还原

【Abstract】 While traveling wave is excited in the stator of a disc piezoelectric motor, the resulted three-dimensional oblique ellipse motion is produced at the friction interface between the stator and the rotor. In this case the radial component of the elliptical motion will lead to pure friction loss and transmission efficiency reduction. The kinematics characteristics of the vibration response of the disc piezoelectric stator were investigated. It was proposed that the stator with teeth was modeled by a teeth structure attached to the main substrate. The vibration equation of the stator was derived by the dynamic substructure method and finite element method, and the particle on the driving surface of stator teeth was analyzed. It is pointed out that the proportion of the displacement component in the radial direction can be reduced by the structural parameters design of the teeth. As an example the teeth of some kind of disc piezoelectric motor were optimized in order to obtain the best transmission efficiency of the contact interface between the stator and rotor. The parameters with better output efficiency were achieved by a series of iteration. The output characteristics of the piezoelectric motor with optimal parameters were computed and analyzed by comparison with those of other parameters. The prototype of the disk piezoelectric motor with specific parameters was manufactured. It is proved that the structural parameters of stator teeth have a considerable effect on the power loss owing to the radial sliding on the friction interface. Under the same excitation conditions, the excellent output efficiency can be achieved by using the stator with the optimal parameters group.更多还原