基于负载变化的超声振子电学性能试验研究

针对超声波加工中振幅衰减和振幅不稳定现象,通过超声振子的静态加载试验,分析了轴向与径向加工负载力对超声振子电学特性的影响规律,以及超声振子电学参数的变化对超声振幅的影响机制。结果表明,超声振子的电学参数在径向负载力与轴向负载力的影响下有相似的变化趋势,即超声振子谐振频率与动态电阻随着负载力的增加而单向增大,动态电感与动态电容有相反的变化趋势,二者的综合效果使谐振频率随着负载力的增加而增大,静态电容在一定范围内波动,当超声振子所受的负载力增大到一定值时,超声振子的低频谐振点会消失。依据理论分析与试验研究结果,提出了改善振幅衰减和振幅不稳定现象的措施。

Experimental Study on Electrical Performance of Ultrasound Vibrator Based on Load Change

Aiming at the phenomenon of amplitude attenuation and amplitude instability in ultrasonic machining,studying the influence rule of the axial and radial processing load force on the electrical characteristics of the ultrasonic vibrator was analyzed,and studying the mechanism of the influence of the change of the electrical parameters of the ultrasonic vibrator on the ultrasonic amplitude,through the static loading experiment of the ultrasonic vibrator.The results showed that,the electric parameters of the ultrasonic vibrator have similar changing trend under the radial load force and the axial load force.The dynamic resistance increases unidirectionally with the increase of load force.Dynamic inductance and dynamic capacitance have opposite changing trend,and they cause the resonant frequency increases with the increase of load force together.The static capacitance fluctuates within a certain range.The low-frequency resonance point of the ultrasonic vibrator will disappear,when the cutting force of the ultrasonic vibrator increases to a certain value.According to the theoretical analysis and experimental results,the measures to improve amplitude attenuation and amplitude instability are proposed.