【摘要】 研究了一种夹心式压电陶瓷高频超声换能器的厚度振动特性.换能器由前后金属盖板、厚度方向极化的压电陶瓷薄圆环共轴连接而成.其横向尺寸远大于纵向尺寸.应用一维设计理论,分析了压电陶瓷圆环的厚度振动特性,得出了其机电等效电路和共振频率方程.并用网络级联理论,推出压电陶瓷晶堆的机电等效电路.设计并制作了一组厚度振动夹心式压电陶瓷超声换能器,对其共振频率进行测试.实验表明测量值和理论计算值符合较好.更多还原

【Abstract】 A sandwich piezoelectric ceramic ultrasonic transducer in thickness vibration is studied.The transducer consists of the front and back metal masses,the coaxially segmented thickness polarized piezoelectric ceramic thin ring.For this kind of sandwich piezoelectric transducers,it is required that the lateral dimension of the transducer is sufficiently large compared with that of the longitudinal so that no lateral displacements in the transducer can occur(laterally clamped).The thickness vibration of piezoelectric ceramic ring is analysed and its electro-mechanical equivalent circuit is obtained.The thickness vibration of a piezoelectric ceramic stack consisting of a number of identical piezoelectric thin circular rings is analysed and its electro-mechanical equivalent circuit is also obtained using network analysis theory.Based on the frequency equation,a set of sandwich piezoelectric ceramic ultrasonic transducers are designed and manufactured,and their resonance frequencies are measured.It is shown that the measured resonance frequencies are in good agreement with the theoretical results.更多还原