U形直线超声电机结构设计

针对直线超声电机的小型化问题,提出一种新型U形直线超声电机,该电机由U形定子和导轨组成,压电陶瓷片采用粘贴的方式固定在定子上.研究了电机的激振方式与位置,设计并加工了直线超声电机样机和测试装置.将柔性铰链结构应用到直线超声电机夹持中.通过实验确定了电机的最佳工作频率、预压力.研究了输出力和空载速度随工作频率、预压力和电压的变化规律.实验表明,电机在电压值400 Vpp,预压力25N条件下,最大空载速度470 mm/s,最大输出力9N,定子质量25 g,推重比达36;柔性夹持能提高电机的模态一致性和效率,同时简化了电机结构.该研究为电机小型化发展奠定基础.

Structure design of a linear ultrasonic motor with a U-shaped vibrator

Considering the miniaturization of a linear ultrasonic motor(LUSM),a U-shaped linear ultrasonic motor was proposed.The motor consists of a U-shaped stator,slider,and piezoelectric ceramics attached to the stator.The problem of where and how to excite the mode was discussed.A prototype and its test equipment were fabricated.The flexible hinge structure was used in the linear ultrasonic motor gripper.The motor’s optimum working frequency and pre-pressure were obtained by the experiments.The output force and velocity changed with the working frequency,and the pre-pressure and voltage were studied.When the value of the voltage is 400Vpp and the pre-pressure is 25N,the maximum no-load speed is 470mm/s,the maximum output force is 9N,the stator’s mass is 25g and the thrust-weight ratio is 36.The flexible gripper can improve the motor’s modal consistency and efficiency,and can also simplify the structure.This research settles the basis for the miniaturization of a linear ultrasonic motor.