EDM machine development

Soviet scholar Lazarenko and his wife invented the EDM machine, which then developed rapidly with the improvement of pulse power supply and control system. The pulse power supply used initially was a simple resistor-capacitor circuit. In the early 1950s, it was improved to a resistor-inductor-capacitor circuit. At the same time, the so-called long pulse power supply such as pulse generator was used to improve the etching efficiency and reduce the relative loss of tool electrode.
Subsequently, high-frequency pulse power supplies such as high-power electron tubes and thyristors appeared, which improved the productivity under the same surface roughness conditions. In the mid-1960s, transistor and thyristor pulse power supplies appeared, which improved energy utilization efficiency and reduced tool electrode loss, and expanded the adjustable range of rough and fine machining.
By the 1970s, power supplies such as high-low voltage composite pulses, multi-circuit pulses, equal-amplitude pulses and adjustable waveform pulses appeared, and new progress was made in machining surface roughness, machining accuracy and reducing tool electrode loss. In terms of control systems, from the initial simple maintenance of the discharge gap and control of the advance and retreat of the tool electrode, it gradually developed to the use of microcomputers to timely control various factors such as electrical parameters and non-electrical parameters.