超声研齿换能器的设计与研齿试验

Design and experiments of transducer-horn of ultrasonic lapping of gears

介绍了超声研齿的原理与方法,并将超声加工应用于齿轮研磨。利用力电类比和四端网络法,构建超声研齿换能器的等效网络图,通过电路运算,得到了换能器的频率方程与前后端面振速比的计算公式。据此设计了谐振特性良好的1/2波长超声换能器。进行了超声研齿与普通研齿对比试验,利用扫描电镜(SEM)图像分析了两者的材料去除机理。试验表明超声研齿材料去除率可达到普通研磨的3倍,且齿面质量明显提高,齿面粗糙度Ra低至0.2mm,水平截距c减小到1.2!m。

We introduce the method of ultrasonic lapping of bevel gears, and use ultrasonic machining in lapping of gears. Based on the principle of four-terminal networks, equivalent electric circuit diagrams of the transducer-horn are constructed by using mechano-electrical analogy. Equations for frequency and the amplification factor of the transducer-horn are derived from the equivalent circuit Based on the expressions, a set of transducer-horn with favorable resonance performance has been designed. Experiments of the ultrasonic and conventional lapping have been carried out, and the material removal mechanics analyzed with SEM photographs of tooth surfaces. The experiments show that the material removal rate of ultrasonic lapping is three times that of the conventional ones. Ultrasonic lapping also produces better tooth surface quality with roughness Ra=0.2mm, section height c=1.2μm.