径扭复合模式盘形压电超声换能器

Radial-torsional Vibration Mode of Disc-type Piezoelectric Transducer

提出一种新型的斜缝式结构径扭复合模式振动盘形压电超声换能器,并对其径扭复合模式振动进行了理论和试验研究。通过对斜槽处应力的分解,引入两个机械转换系数,依据机电类比原理,建立起换能器的径扭复合模式振动耦合机电等效电路模型,从等效电路得到换能器的径扭复合振动频率方程,探讨狭缝的斜角对换能器共振频率的影响,数值计算表明换能器共振频率随斜角增大而降低。试验加工三个不同斜度狭缝的换能器,并对其共振频率进行了测试和有限元法模态仿真计算,结果表明,理论与仿真值及试验结果吻合较好。

A new kind of radial-torsional composite mode ultrasonic transducer with multiple slanting slots is presented and studied. Two mechanical conversion coefficients are introduced by resolving the stress at chutes. Based on the electromechanical analogy, the coupled equivalent circuit model of the vibration system is set up and the frequency equation is derived. The effect of the oblique angle of the slots on the resonance frequency of the transducer is analyzed. It is concluded that the resonance frequency decreases with the increase of oblique angle. Furthermore, the resonance frequencies of three transducers with different oblique angle of slots are measured and simulated by using finite element method. Experimental results show that the measured frequencies of the transducers are in good agreement with the theory and simulation results.