| 摘要 |
PURPOSE:To restrain a positional shift between an electrode and a workpiece due to thermal deformations in machine structure members to reduce machining errors, by providing, in an electric discharge machining apparatus, a device for ventilating and cooling the body of the apparatus with the use of discharge air from a fan cooler for coling machining liquid. CONSTITUTION:Upon electric discharge machining of a workpiece 5 machining liquid 2 having an elevated temperature in a machining tank 1 is returned into a machining liquid tank 14. The machining liquid 2 having a high temperature is cooled down by a fan cooler 13 on the way of feed from the machining liquid tank 14 to the machining tank 1 by a supply pump 20. Thermal energy of the machining liquid 12 which is abrorbed by suction air 15 heats the latter itself, and fan cooler discharge air 16 passes through the insides of bed 10 and column 9 by way of a fan cooler discharge air duct 17, and is discharged to the upper section of the column 9 and the front section of the bed 10 from a discharge air port 19. Accordingly, the machining liquid 2 in the machining tank 1 is also cooled down, and therefore, temperature rises in an electrode 3, a spindle 4, a workpiece 5, a table 6, a saddle 7 and a head 8 may be restrained, thereby the temperature distribution of the entire apparatus may be made uniform. |
