Abstract: Provided is a wire electric discharge machining device and method capable of reliably terminating a short circuit between a wire electrode and a workpiece. The invention relates to a wire electric discharge machining device that starts machining of a workpiece (3) by generating an electric discharge in a machining gap formed between the workpiece and a wire electrode (2) threaded through a start hole (4) in the workpiece. The wire electric discharge machining device includes: a tension control device (56) that controls tension of the wire electrode so as to maintain the tension at a set value; a short circuit detector (57) that detects a short circuit between the wire electrode and the workpiece; and a short circuit termination system that reduces the tension of the wire electrode and vibrates the wire electrode in order to terminate a short circuit when the short circuit detector has detected the short circuit.

Abstract: Provided is a wire electric discharge machining device and method capable of reliably terminating a short circuit between a wire electrode and a workpiece. The invention relates to a wire electric discharge machining device that starts machining of a workpiece (3) by generating an electric discharge in a machining gap formed between the workpiece and a wire electrode (2) threaded through a start hole (4) in the workpiece. The wire electric discharge machining device includes: a tension control device (56) that controls tension of the wire electrode so as to maintain the tension at a set value; a short circuit detector (57) that detects a short circuit between the wire electrode and the workpiece; and a short circuit termination system that reduces the tension of the wire electrode and vibrates the wire electrode in order to terminate a short circuit when the short circuit detector has detected the short circuit.