Abstract: | This paper describes an electrodischarge machine† for micro-hole boring capable of improved accuracy and performance in boring precision small diameter holes in components such as ink jet nozzles for printers, electron gun apertures for graphic displays, micro-connectors for high-speed computers, and optical components for telecommunications. Micro-energy discharging permits machining of 15–300 μm diameter micro-holes with a roundness accuracy of 0.5 μm or better and a surface roughness less than 0.1 μm. No bending stress is applied to the tool electrode, therefore high precision machining of cylindrical surfaces, machining with very thin side-walls, and machining of overlapping multiple-holes are all possible, regardless of the hardness of any electrically conductive material. Tool electrodes of any diameter are machinable using reversed-polarity electric discharge and are replaceable in the same way as conventional drills. Travel of the tool electrode is controlled automatically by microprocessor, thus eliminating the need for a skilled operator. |