Storage-capacitor-type EDM power supply

摘要

A storage-capacitor-type EDM power-supply system wherein the storage capacitor is charged from a DC source to store a predetermined amount of charge thereon under the control of a switch connected between the DC source and the capacitor. The discharge circuit connecting the capacitor with an EDM gap to allow the stored charge to be discharged through the latter also includes a switch which is controlledly rendered conductive by a signal pulse generator which provides a controlled switching signal preprogrammed in a microprocessor such that the capacitor discharge machining current has a predetermined waveform corresponding to the preprogrammed signal. Preferably, the machining current in each capacitor-discharge cycle is in the form of a composite pulse consisting of a series of periodically interrupted pulses of a minimum on-time and off-time.