Control device for wire electric discharge machine

A control device for a wire electric discharge machine which repeatedly performs a plurality of machining processes causing a wire electrode and workpiece to relatively move and perform electric discharge machining on the workpiece by following a machining path offsetting by an offset value from a machined shape of the workpiece, wherein the offset value differs for the plurality of machining processes, the control device comprising a processor, the processor being configured to:

• look ahead a machining program and analyze a machined shape of the workpiece;
• create, as machining paths for the plurality of machining processes, a plurality of macnining paths of identical circular arc shape offsetting by an offset value from the analyzed machined shape wherein the offset value differs for each of the plurality of machining paths, and a shape of a corner part of each of the plurality of machine paths is an identical circular arc shape;
• create, as machining paths for the plurality of machining processes, a plurality of machining paths of concentric circle shape offsetting by an offset value from the analyzed machined shape wherein the offset value differs for each of the plurality of machining paths, and shape of a corner part of each of the plurality of machining paths is a concentric circle shape;
• and
• select either of the plurality of machining paths if identical circular arc shape and the plurality of machining paths of concentric circle shape, as the machining paths for the plurality of machining processes, based on at least one among the machining program, the analyzed machined shape, the plurality of machining paths of identical circular arc shape, and the plurality of machining paths of concentric circle shape.