ELECTRIC DISCHARGE MACHINING DEVICE

PURPOSE:To prevent generation of machining error by reading the machining liquid cooling data from a control data memory means in accordance with the mean machining current and the rate of machining liquid flow, and controlling the temp. of the machining liquid supplied to the space between electrodes by a control means. CONSTITUTION:When a pulse voltage from a machining power supply 8 is impressed between a work to be machined 2 and machining electrode 1, which are heated by electric discharge to raise also the temp. of the machining liquid 4, so that a control device 22 in an NC device 7 controls a machining liquid cooling means 20. There is a certain time delay between heat emission from the work 2 and the temp. rise in the machining liquid 4, so that the control means 22 reads the mean machining current, the rate of flow of the machining liquid 4, or the cooling ability data corresponding to combination thereof from a control data memory means 21, and on the basis of this read data the machining liquid cooling means 20 is controlled to keep the temp. of the work 2 at a desired value. This prevents generation of the machining error due to dispersion of the temps.