Patent attributes
A dirty fluid tank of a machining fluid supply tank has a capacity smaller than a machining tank and is arranged lower than the machining tank. An intermediate tank has a capacity smaller than the dirty fluid tank, selectively communicates with the dirty fluid tank. A clear fluid tank has a capacity smaller than the intermediate tank, is arranged above the dirty fluid tank and the intermediate tank. The sum of capacities of the dirty fluid tank and the intermediate tank is larger than the capacity of the machining tank. A pipe includes a drain pipeline of the machining tank, a first pipeline for purifying the electric discharge machining fluid and sending the electric discharge machining fluid to the clear fluid tank, and a second pipeline for sending the electric discharge machining fluid from the clear fluid tank to the machining tank.
