三种基于夹心换能器驱动的球形超声马达设计

文章在换能器设计理论基础上利用有限元方法对夹心换能器进行了优化设计,通过改变前端变幅杆的长度、底座高度以及前端厚度的几何参数进行分析,得到了换能器前端变幅杆几何参数与换能器性能之间的关系,变幅杆的长度与换能器固有频率成反比,与振幅成正比,变幅杆的底座高度和前端厚度与固有频率和振幅放大系数皆成反比.以夹心换能器为驱动,提出三种新型多自由度球型马达结构设计,分别介绍了三种马达结构,分析了驱动原理和运动轨迹的实现,对比了相互之间的优缺点.对四换能器球形马达进行了样机试验,实际工作频率为33.300kHz,在驱动电压110V时,最大输出力矩为0.13Nm,最高转速可达46r/min.

Design of Three Kind of Spherical Ultrasonic Motors Based on Sandwiched Transducers

This paper carried out optimization design of sandwiched ultrasonic transducer by applying the finite element method on the basis of the transducer design principle.By changing the front horn's length,the horn base's height and the front tip's thickness,the relationship between the geometrical parameters variation of the transducer front horn and the transducer's performance was attained during the analysis.The horn's length is inverse proportional to the transducer's resonant frequency and proportional to vibration amplitude.Both the horn base's height and the front tip's thickness are inverse proportional to resonant frequency and amplitude magnifying ratio.Three kinds of novel spherical ultrasonic motors(USM)with multiple degrees of freedom driven by sandwiched transducer were designed.These motors structure were introduced while their driving principles and motion trajectory realization were analyzed.Finally,three kinds of motors were compared with each other with regard to their merits and demerits. Experiment was carried out on the prototype of the four-transducer type USM.The working frequency is 33.300kHz.Driven by 110V voltage,the maximum output torque is 0.13Nm,and the maximum revolving speed is 46r/min.