Abstract: A wire cutting electric discharge machine with a wire guide roller having a V-shaped groove beneath the workpiece, and a wire guide between the guide roller and a conveyor belt.

Abstract: An electric discharge wire cutting machine with one nozzle above the workpiece and another nozzle beneath the workpiece, one of the nozzles having a shape obtained by rotating an arc of a circle about the central axis of the conical configuration of the nozzle. This shape allows the working fluid to be smoothly expelled and to prevent the formation of gas bubbles by the wire in the working zone which might prevent adequate cooling of the wire and thereby cuase the wire to break.

Abstract: Method and Apparatus for calculating an offset direction of a wire electrode using inputted offset data which contains the information as to whether the wire electrode should be offset on the inner side or outer side of the theoretical position. The offset data and the advancing direction of the wire electrode are used to determine whether the wire should be offset on the left or right side of the theoretical position.

Abstract: A wire cutting electric discharge machine, in which a wire 27 which has been used a is interposedly supported between opposed top and bottom endless belts 35 and discharged from the machine. The force between the belts 35 with which the wire is interposedly supported can be increased, and the wire 27 can be discharged irrespective of any wear on the belts 35. In addition, in order to extend the life of the belts, during the interval in which the wire is being interposedly supported by the belts, a twist is imparted to the belts and a pair of wire discharge rollers which stretches the wire provided at the rear side of the belts.

Abstract: A wire cutting electric discharge machine which carries out an electric discharge process on a workpiece using a wire electrode of normal diameter, for example, 0.1 mm or greater, can also be used with a fine wire electrode with a diameter of less than 0.1 mm. The fine wire electrode can only withstand a small tension because of its extremely small diameter, so that a wire disposal device for disposing a normal wire electrode cannot be used. Therefore, a wire disposal device for a fine wire electrode is provided adjacent to the lower wire guide device, and the force with which the wire is wound up by the wire disposal device is sufficiently smaller than the tension of the fine wire electrode, so that the wire disposal process does not produce breakage in the fine wire electrode. In addition, the lower wire guide device can be used in common for a normal wire electrode, and as required, can be changed for use with a fine wire electrode.