静電誘導給電法を用いた放電加工の微細化

摘要

This paper describes the limit of miniaturization of micro EDM using the electrostatic induction feeding method. In this method, it is possible to minimize the influence of the stray capacitance existent parallel to the working gap because the point of electric feeding can be located near the working gap. Hence, the minimum discharge energy is smaller than that of the relaxation pulse generator. As a result, the diameter of discharge craters of this method was 0.4μm, smaller than that of the relaxation pulse generator by 0.3μm. Therefore, the minimum diameter of rods obtained using this method was 0.8μm, smaller than that of the relaxation pulse generator by 0.1 μm. Moreover, the success probability of fabrication of micro rods thinner than 2.0μm in diameter was two times higher than that of the relaxation pulse generator.%1．緒　　　言近年，機械部品の小型化や複雑化が進み，サブミクロンオーダーの加工も要求され始めている．従来の微細放電加工機ではRC放電回路を用いてコンデンサに蓄えたエネルギーを1回の放電エネルギーとして放出して放電加工を行う．最終の仕上げ加工では，外付けのコンデンサの容量をゼロにして，給電線間，工具電極ホルダと加工テーブル間に生じる浮遊容量，および工具電極と工作物間に生じる浮遊容量（極間容量）のエネルギーのみで加工を行う．