A wire electrical discharge machine includes: a gap voltage detector for detecting a voltage across an electrode gap; a first voltage control unit for applying a first voltage to the electrode gap; a discharge determiner for determining whether or not the electrode gap is in a discharging state during application of the first voltage; and a second voltage control unit for supplying a machining current through the electrode gap when the electrode gap is in a discharging state. After a supply of the machining current to the electrode gap, even when a discharge is induced by the next application of the first voltage to the electrode gap, the second voltage control unit prohibits application of a second voltage to the electrode gap.

A wire electrical discharge machine includes: a gap voltage detector for detecting a voltage across an electrode gap; a first voltage control unit for applying a first voltage to the electrode gap; a discharge determiner for determining whether or not the electrode gap is in a discharging state during application of the first voltage; and a second voltage control unit for supplying a machining current through the electrode gap when the electrode gap is in a discharging state. After a supply of the machining current to the electrode gap, even when a discharge is induced by the next application of the first voltage to the electrode gap, the second voltage control unit prohibits application of a second voltage to the electrode gap.

A substrate includes a multilayer substrate body in which a plurality of circuit bodies are laminated in a laminating direction through insulating layers and are interlayer connected via a connected conductor formed on each of the insulating layers, and a magnetic body that is arranged in the laminating direction while at least a part of or all of the magnetic body sandwiches the circuit bodies. Each of the circuit bodies includes at least a first circuit body and a second circuit body. The first circuit body is formed of a first extending portion and a first folding portion. The second circuit body is formed of a second extending portion and a second folding portion.

A substrate includes a multilayer substrate body in which a plurality of circuit bodies are laminated in a laminating direction through insulating layers and are interlayer connected via a connected conductor formed on each of the insulating layers, and a magnetic body that is arranged in the laminating direction while at least a part of or all of the magnetic body sandwiches the circuit bodies. Each of the circuit bodies includes at least a first circuit body and a second circuit body. The first circuit body is formed of a first extending portion and a first folding portion. The second circuit body is formed of a second extending portion and a second folding portion.

An electrical discharge machining apparatus and an electrical discharge machining method with adjustable machining parameters comprise a carrier and an electrical discharge machining (EDM) unit. The carrier is used for placing a to-be-machined object defined with a machining target area. A discharge electrode of the electrical discharge machining (EDM) unit is used to cut the machining target area of the to-be-machined object along a first cutting direction with at least one machining parameter, the machining parameter is correspondingly adjusted when a specified parameter of the to-be-machined object changes to a first numerical value, thereby using the adjusted machining parameter to perform a second cutting step on the machining target area of the to-be-machined object. A segmented cutting technology for solving a problem that a cutting speed (mm.sup.2/min) is slowed down and a total cutting time is prolonged due to changes of the specified parameter of electrical discharge machining cutting.

A method for the monitoring of a wire electrical discharge machining (WEDM) process, the method comprising the steps of: setting a unit observation length for the signal acquisition, continuously acquiring at least one process signal which is representative of an amount of material removed by at least one discharge and the position (X;Y) of said at least one discharge, and determining, based on said at least one process signal and one or more properties of a current machining, a cumulated amount of material removed per unit observation length along a machining path, including amounts of material removed by travelling in a forward cutting direction and amounts of material removed by travelling in a reverse cutting direction.

A method for the monitoring of a wire electrical discharge machining (WEDM) process, the method comprising the steps of: setting a unit observation length for the signal acquisition, continuously acquiring at least one process signal which is representative of an amount of material removed by at least one discharge and the position (X;Y) of said at least one discharge, and determining, based on said at least one process signal and one or more properties of a current machining, a cumulated amount of material removed per unit observation length along a machining path, including amounts of material removed by travelling in a forward cutting direction and amounts of material removed by travelling in a reverse cutting direction.

A multiwire electric discharge machine includes: a machining power source that applies a machining pulse voltage between a workpiece and a cutting wire section; and a wire breakage detection unit that detects breakage of a wire electrode. The wire breakage detection unit is electrically connected in parallel to a wire electrode portion stretched over a section from one location on the feeding side of the wire electrode to one location on the ejection side of the wire electrode, and the wire breakage detection unit includes: a wire breakage detection circuit in which a wire breakage detection power source constantly supplying direct current to the wire electrode portion at least while the workpiece is undergoing a cutting process and a current limiting resistor are connected in series; and a wire breakage determination unit that determines breakage of the wire electrode based on current flowing through the current limiting resistor.

A multiwire electric discharge machine includes: a machining power source that applies a machining pulse voltage between a workpiece and a cutting wire section; and a wire breakage detection unit that detects breakage of a wire electrode. The wire breakage detection unit is electrically connected in parallel to a wire electrode portion stretched over a section from one location on the feeding side of the wire electrode to one location on the ejection side of the wire electrode, and the wire breakage detection unit includes: a wire breakage detection circuit in which a wire breakage detection power source constantly supplying direct current to the wire electrode portion at least while the workpiece is undergoing a cutting process and a current limiting resistor are connected in series; and a wire breakage determination unit that determines breakage of the wire electrode based on current flowing through the current limiting resistor.

The invention relates to a method and device for wire electrical discharge machining (WEDM), in which a first voltage UCH1 is measured between a first current feeder and the workpiece, and a second voltage U.sub.CH2 is measured between a second current feeder the workpiece, whereas said first- and second voltage U.sub.CH1, U.sub.CH2 are measured when current of the machining discharge pulse is zero, for instance at the end of the of the machining discharge current pulse, and a voltage difference of said measured voltages ΔU.sub.CH=U.sub.CH1−U.sub.CH2 is determined, and a discharge position of said machining discharge pulse is determined in real time, as a function of said voltage difference ΔU.sub.CH.