A wire electric discharge machining apparatus includes upper and lower wire guide units including wire guides configured to position and guide a wire electrode and a jet nozzle configured to supply a jet flow coaxially with the wire electrode, and a core holding pad having a through-hole passing therethrough in an upward/downward direction, and in which a plurality of protrusion sections having an equal distance from upper surfaces thereof to a lower surface of the workpiece are formed. The core holding pad is disposed on the lower wire guide unit such that the core holding pad approaches the lower surface of the workpiece as closely as possible.

A wire electrical discharge machine includes a wire feeding hole position acquisition unit configured to obtain a position of a wire feeding hole that allows for insertion and feeding of a wire electrode. In this wire electrical discharge machine, when the position of the wire feeding hole obtained by the wire feeding hole position acquisition unit is deviated from a wire feeding position defined by a machining program, a wire feeding control unit controls a machine main body to move the wire electrode to the position of the wire feeding hole and feed the wire electrode there, and a machining control unit controls the machine main body to perform electrical discharge machining on a workpiece with the wire electrode while moving the wire electrode on a path segment between a position where the wire electrode has been fed and the wire feeding position defined by the machining program.

A program editing device is configured such that, when an arc-shaped partial path is selected from a machining path displayed on a display unit based on route information of each of plural blocks, the program editing device calculates a change amount of the radius of curvature of the selected partial path in accordance with an operation of changing the state of the arc of the selected partial path and revises the block corresponding to the selected partial path based on the change amount.

A method of yielding a thinner product wafer from a thicker base SiC wafer cut from a SiC ingot includes: supporting the base SiC wafer with a support substrate: and while the base SiC wafer is supported by the support substrate, cutting through the base SiC wafer in a direction parallel to a first main surface of the base SiC wafer using a wire as part of a wire electrical discharge machining (WEDM) process, to separate the product wafer from the base SiC wafer, the product wafer being attached to the support substrate when cut from the base SiC wafer.

A method of yielding a thinner product wafer from a thicker base SiC wafer cut from a SiC ingot includes: supporting the base SiC wafer with a support substrate: and while the base SiC wafer is supported by the support substrate, cutting through the base SiC wafer in a direction parallel to a first main surface of the base SiC wafer using a wire as part of a wire electrical discharge machining (WEDM) process, to separate the product wafer from the base SiC wafer, the product wafer being attached to the support substrate when cut from the base SiC wafer.

A method for producing a coil for electric apparatus of the present invention is the method for producing a coil for electric apparatus for cutting spirally a block-shaped workpiece formed with a cylindrical portion corresponding to the coil in a circumferential direction of the cylindrical portion, the spiral coil is formed by turning a cutting means while moving it relatively to the workpiece from a part corresponding to one end of the coil to a part corresponding the other end of the coil along a machining line spirally set in the circumferential direction of the cylindrical portion. According to the invention, since the coil is formed by cutting the continuous cutting machining plane without generating a step in design from the block-shaped workpiece formed with a cylindrical portion corresponding to the coil using a wire-tool etc., it is possible to constitute a high-quality coil.

A wire electrical discharge machine includes: a voltage application unit for repeatedly applying a voltage to an electrode gap between the workpiece and the wire electrode at a predetermined cycle; a switching element connected in parallel with the electrode gap and configured to short-circuit the electrode gap; and a control section for controlling the switching element so as to short-circuit the electrode gap in a pause period during which the voltage is not applied. The control section adjusts a short-circuiting period in which the electrode gap is short-circuited according to the machining shape specified by a machining program.

Methods of repairing a part having a firtree-shaped feature requiring rework are disclosed. An embodiment of the method includes receiving the part having the firtree-shaped feature requiring rework. The part is installed in a machine configured for wire electrical discharge machining (EDM). A location of the firtree-shaped feature relative to a datum of the machine is then determined. Wire EDM is performed on the firtree-shaped feature.

A wire electrical discharge machine includes: a detection unit configured to detect a contact state in which the wire electrode contacts the workpiece, and a contact release state in which the wire electrode that is in the contact state is separated from the workpiece; a vibration unit configured to, if the contact state is detected during the machining of the workpiece, stop relative movement of the wire electrode and vibrate the wire electrode about a stop position at which the relative movement of the wire electrode has been stopped; and a relative movement control unit configured to resume relative movement of the wire electrode if the contact release state is detected until a predetermined time elapses from when the contact state has been detected or until the number of times that the wire electrode is vibrated reaches a predetermined number of times.

Methods and systems for wire-electro discharge machining of components are described. The method comprises machining a first component by moving a wire-EDM electrode along a first set of cutting paths associated with a plurality of cutting passes, the cutting paths determined based on a desired profile shape of the component, obtaining a cutting parameter of the first component post-machining, determining a first modified cutting path for a second component based on the cutting parameter, and machining the second component by moving the wire-EDM electrode along a second set of cutting paths associated with the plurality of cutting passes, the second set of cutting paths comprising the first modified cutting path.