POWER SUPPLY FOR WIRE ELECTRIC DISCHARGE MACHINING

摘要

A power supply for wire electric discharge machining in which voltages of both positive and negative polarities can be applied between a wire electrode (1a) and a work (2). The power supply comprises a control means (14) for applying a first voltage pulse between the wire electrode and the work for a predetermined time T1 and then applying a second voltage pulse of opposite polarity for a predetermined time T2a from the time when a predetermined time t predetermined for preventing breakdown of a switching means elapses until the voltage between the wire electrode and the work lowers to a specified level Va at which discharge can start. At least two machinings out of three machinings in machining liquid, mist and air are combined to realize high-accuracy, high-reliability wire electric discharge machining.