Patent ID: 6980879

Claim:
A controller for a wire electric discharge machine performing electric discharge machining by applying electric discharge pulse current between a wire electrode and a workpiece while said wire electrode and said workpiece are caused to relatively move to each other, comprising: discharge pulse number counting means for counting a discharge pulse number applied every predetermined time; moving means for relatively moving said wire electrode and said workpiece to each other along a machining path on the basis of a moving command; reference discharge pulse number memory means for storing a discharge pulse number which is used as a reference; means for determining a ratio of a numerical value obtained by said discharge pulse number counting means to a numerical value stored in said reference discharge pulse number memory means; and means for outputting, to said moving means, distance obtained by multiplying relative moving distance between said wire electrode and said workpiece to be determined by a preset feed speed and said predetermined time by said ratio as a moving command every said predetermined time.