微细倒锥孔电火花加工机构设计及其实验研究

Mechanism Design for Micro EDM Drilling of Negative Tapered Holes and its Experiments

研制了一种微细倒锥孔电火花加工机构模块,该模块在维持电极丝本身不旋转的状态下,控制电极丝端部偏转,以此加工出微细倒锥孔。分析了影响机构加工精度的主要因素,并实验研究了加工过程中脉冲电压、放电电容对加工孔形状的影响。结果表明,用直径120μm的电极丝可在1 mm的钢片上加工出入口孔径190μm、出口孔径220μm的倒锥孔。

A mechanical module was developed for micro EDM （electro discharge machining） drill- ing of negative tapered holes. Using this mechanism, the end of wire electrode is controlled to deflect and swing circumferentially, to machine negative tapered holes along with the electrode＇ s feeding. The mechanism error and its main factors influencing machining accuracy were analyzed. And the process parameters affecting the shape of holes, such as pulse voltage and discharge capacity were also experimented. Results showed that negative tapered holes with inlet diameter of 192μm and outlet diameter of 220μm could be obtained on a steel plate with thickness of 1mm, by using a tool electrode diameter of 120μm.