超声手术刀声学系统设计和实验

Acoustic system design and test of ultrasonic scalpel

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,提出了一种最速曲线过渡段的复合变幅杆,并对装配有该变幅杆的超声刀声学系统进行一系列实验。首先,基于等效电路法,设计了夹心式压电换能器和最速曲线型变幅杆的基本结构。在此基础上,结合超声刀的工作条件和材料特性,对换能器-变幅杆基本结构进行精确设计。然后,利用有限元法和实验法获取了换能器纵振频率以及频率响应曲线,证明了该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:应用最速曲线的超声刀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,满足设计需求。

For ensuring both 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 horn based on the fastest curve transition section,a series of tests are carried out on the ultrasonic knife acoustic system equipped with the ultrasonic horn.Firstly,based on the equivalent circuit method,the basic structure of sandwich piezoelectric transducer and fastest curved luffing rod is designed.On this basis,combined with the working conditions and material characteristics of ultherapy,the basic structure of transducer-luffing rod is accurately designed.Then,the transducer longitudinal vibration frequency and frequency response curve are obtained by finite element method and experimental method,which further demonstrates 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 ultrasonic knife transducer with the fastest curve are consistent with the design objectives and simulation results.After the load is connected,the coagulation and cutting effect are good,which meets the design requirements.