三棱柱形直线超声电机

A Triangular Prism Shaped Linear Ultrasonic Motor

提出一款三棱柱形直线超声电机。电机定子为由二片压电陶瓷片黏接在三棱柱结构的弹性体上构成。每片压电陶瓷片产生的空间激励力都与两个工作模态的振动方向有一夹角,单片陶瓷片即能激励出两个工作振动模态,而且两者振动响应存在一个相位差。研究了电机定子驱动机制模型,推导了电机单相、两相激励时驱动质点的运动轨迹,分析了电机单相、两相驱动原理。对制作样机的机械性能进行了测试,试验表明电机可在较宽的频率范围内平稳运行,当驱动电压峰峰值为250V时,该电机单相、两相驱动的最大速度分别为2.2、2.5mm/s,最大输出力分别为0.156、0.192N,是定子质量的8.6倍、10.6倍。

A triangular prism shaped linear ultrasonic motor was proposed. The stator comprises a triangular prism shaped elastic body and two piezoelectric ceramics, which are attached to the two outer surfaces of the elastic body. The spatial excitation force generated by each piezoelectric ceramic is at an angle with respect to the vibration direction of each working mode. Each piezoelectric ceramic can excite the two working vibration modes. And there is a phase difference between the vibration responses. A model for the driving mechanism of the motor was developed. The expressions of motion trajectory of the driving points were formulated when the stator was excited by single-phase or two-phase electrical sources. Driving principle of the motor with single-phase and two-phase excitation was analyzed. The performance of a prototype motor was measured. The experimental results show that the motor can operate smoothly in a wide frequency range. When the motor is driven by single-phase and two-phase electrical sources at a voltage of 250V（peak-to-peak）, the speeds without load are 2.2 and 2.5mm/s, and the maximum output forces are 0.156 and 0.192 N, which are 8.6 times and 10.6 times of the stator weight respectively.