为了有效提高超声电机的机械输出性能,研制了一种微小型贴片式纵弯复合激励式圆筒型行波超声电机。该电机由圆筒和一个纵弯复合换能器组成,换能器位于圆筒的外侧壁上,换能器由一对弯振压电陶瓷片、一对纵振压电陶瓷片和前端为变幅杆的长方形铝块组成。对电机的工作原理进行了分析,利用有限元方法对电机进行了设计与仿真,实现了电机两个基本振动模态特征频率的简并。对振动特性进行了测试,测试结果与有限元分析结果吻合良好。测试结果表明,换能器的纵振、弯振和圆筒弯振模态之间均实现了很好的匹配。
In order to improve the mechanical performance of ultrasonic motor, a miniature patch cylindrical traveling wave ultrasonic motor using longitudinal bending composite excitation is proposed. The motor is composed of a cylinder and a longitudinal-bending transducer located on the lateral wall of the cylinder. The transducer is made up of a pair of bending vibration piezoelectric ceramic plates, a pair of longitudinal vibration piezoelectric ceramic plates and a rectangular aluminum piece whose front end is the amplitude transformer. The motor is designed and simulated using finite element method based on the analysis of the working principle of the motor, which realizes frequency degeneracy of the two basic vibration modes of the motor. The vibration characteristics are tested. The test results well agree with the results of finite element method, and show that longitudinal vibration mode, bending vibration mode and cylindrical bending vibration mode match well.