用于超声乳化手柄的压电换能器设计及实验研究

Design and Experimental Verification of Piezoelectric Transducer for Phacoemulsification Handpiece

针对白内障超声乳化吸除术的需求,设计一款与传统超声乳化手柄中的40kHz纵向振动压电换能器相比,热安全更好,乳化更高效且最大振幅达到手术需要的超声换能器。压电换能器设计模态为29kHz一阶纵向振动,并验证该换能器的频率及振幅特性。使用有限元分析软件ANSYS17.0对该压电换能器进行模态仿真;使用多普勒激光测振仪对换能器样机从径向及轴向进行扫频与定频分析,将其结果与仿真数据及设计数据进行比较分析。样机实验表明:仿真分析得到压电换能器模态与设计非常接近,振动形态为一阶纵振,谐振频率28.63kHz与设计频率误差为2.17%;使用多普勒激光测振仪测得该换能器为纵向振动,谐振频率为29.46kHz,与设计频率误差为1.59%;在固定电压下得到该换能器频率-振幅关系,在固定频率下得到该换能器电压-振幅关系,验证该换能器最大振幅能够达到超声乳化手术需要,且振幅随电压稳定增大。本设计成功达到预期频率及振幅要求,仿真结果和实物测试充分验证了该设计的正确性。

To meet the specifications of phacoemulsification during cataract surgery,an ultrasonic transducer with better thermal safety,more efficient emulsification,and suitable maximum amplitude compared with the traditional 40kHz longitudinal phaco handpiece was designed.The design mode of the ultrasonic transducer was in first-order longitudinal vibration at 29kHz,the operating frequency and amplitude of the transducer were verified as well.The finite element analysis software ANSYS17.0 was used to simulate the vibration mode of the piezoelectric transducer.The Doppler laser vibrometer was used to analyze the sweep frequency and fixed frequency of the prototype transducer from its radial and axial directions,and the results were compared with the simulation data and design data.The prototype experiment has shown approximately the same results that the simulated vibration mode of the transducer was in first-order longitudinal vibration with a resonance frequency of 28.63kHz which is 2.17%error from the designed mode.The measurement taken by Doppler laser vibrometer shows that the transducer was in longitudinal vibration with a resonance frequency of 29.46kHz,and the error was 1.59%with the designed frequency.The relationship between frequency-amplitude of the transducer was obtained at a fixed voltage,and such relationship verified that the maximum amplitude of the transducer could meet the requirements of phacoemulsification cataract surgery,and the amplitude increased with the voltage stably.It is demonstrated that the product successfully reached the expected frequency and amplitude.The simulation results and sample test fully verified the correctness of the design.