3-DIMENSIONAL SHAPING BY DOT-MATRIX ELECTRICAL-DISCHARGE MACHINING

This paper deals with a new prototyping method called dot-matrix elect rical discharge machining (EDM) with scanning motion. The machining pr ocess by the dot-matrix method is similar to printing motion with a do t-impact printer. This method can be applied not only to EDM but also electrochemical machining and forming. A prototype of the machining un it for the dot-matrix method has six feeding devices for thin wire ele ctrodes. The electrodes of 300 mu m in diameter are arranged with the pitches of 760 mu m. To obtain a smooth surface, a planetary motion in the x-y-plane is added to the feeding of the machining unit in the z- direction, the same area is machined repeatedly, or the machining unit is moved with fine feed. By compensating for the wear of the electrod e during the scanning EDM, various shapes with the accuracy of-microme ters order can be obtained without a formed tool electrode. (C) 1997 E lsevier Science Inc.