超声手术刀声学系统设计和实验*

为兼顾阶梯型变幅杆的高放大系数以及曲线过渡变幅杆突变截面处的高疲劳强度,本文提出了一种最速曲线过渡段的超声刀换能器。首先,基于等效电路法,设计了夹心式压电换能器的基本结构。在此基础上,结合超声刀的工作条件和材料特性,对换能器基本结构进行精确设计；然后,利用FEM法和实验法获取了换能器纵振频率以及频率响应曲线,进一步证明了本文所设计换能器的有效性；最后,对所设计的换能器进行了一系列测试,结果表明：测定了无负载换能器谐振频率与输出端振幅,与设计目标、仿真结果相吻合；连接负载后凝血,切割效果良好。

Acoustic system design and test of ultrasonic scalpel

In order to take into account the high amplification coefficient of the stepped horn and the high fatigue strength at the sudden change section of the curve transition horn, this paper proposes an ultrasonic knife transducer with the fastest curve transition section. Firstly, the basic structure of sandwich piezoelectric transducer is designed based on equivalent circuit method. On this basis, combined with the ultrasonic knife working conditions and material properties, the basic structure of the transducer is accurately designed. Then, the transducer longitudinal vibration frequency and frequency response curve are obtained by FEM and experimental method, which further proves the effectiveness of the transducer designed in this paper. Finally, a series of tests are carried out on the designed transducer. The results show that the resonant frequency and output amplitude of the loadless transducer are measured, which is consistent with the design goal and simulation results. Connected to the load after coagulation, cutting effect is well.