A wire electrical discharge machine for detecting an end face of an object, configured so that when a contact detection movement is started and if contact between the wire electrode and the workpiece is detected, positions in which the contact between the wire electrode and the workpiece is detected are stored as contact detection positions and that when a non-contact detection movement is then started and if non-contact between the wire electrode and the workpiece is detected, positions in which the non-contact between the wire electrode and the workpiece is detected are stored as non-contact detection positions. When it is determined whether or not a set number of times of execution is reached and if the set number of times of execution is reached, a reference position is obtained by adding the radius of the wire electrode and a clearance of the wire guide to an end face determination position.

A machining path drawing apparatus for a wire electric discharge machine that draws a machining path for the wire electric discharge machine having a core fixation function includes a machining shape information calculation unit for analyzing a machining program to determine machining shape information, a core fixation function operating region detection unit for determining a region where the core fixation function operates in the machining shape information, and a machining path drawing unit for drawing the region where the core fixation function operates with a display attribute changed when a machining path is drawn based on the machining shape information.

A machining path drawing apparatus for a wire electric discharge machine that draws a machining path for the wire electric discharge machine having a core fixation function includes a machining shape information calculation unit for analyzing a machining program to determine machining shape information, a core fixation function operating region detection unit for determining a region where the core fixation function operates in the machining shape information, and a machining path drawing unit for drawing the region where the core fixation function operates with a display attribute changed when a machining path is drawn based on the machining shape information.

When machining of a workpiece is started in a wire electric discharge machine, before a voltage is applied between a wire electrode and the workpiece (a machining gap), practicable shaft feed control systems are discriminated on the basis of machining conditions set in advance. According to the discrimination, running into an inability state of continuity of machining and an accuracy failure after machining are prevented beforehand.

Electric discharge machining is halted during machining program operation, and a position of the machining halt point is stored. A wire electrode is retreated from the machining halt point to an arbitrary position in which a short-circuit with a workpiece is removed (retreat position), by interrupt operation in which axis movement is performed manually. Then, a return is made from the retreat position to the machining halt point while electric discharge machining is performed, machining program operation is started from the machining halt point, and electric discharge machining is restarted.

A wire electric discharge machine performs electric discharge machining on a workpiece by relatively moving a workpiece placed on a workpiece table and a wire electrode supported by upper and lower wire guides according to a machining program. The wire electric discharge machine comprises an interference determination unit configured to determine whether or not the top or bottom surface of the workpiece table interferes with the wire electrode at the height of the surface during the execution of the machining program.

A wire electric discharge machine performs electric discharge machining on a workpiece by relatively moving a workpiece placed on a workpiece table and a wire electrode supported by upper and lower wire guides according to a machining program. The wire electric discharge machine comprises an interference determination unit configured to determine whether or not the top or bottom surface of the workpiece table interferes with the wire electrode at the height of the surface during the execution of the machining program.

A wire electrical discharge machine includes a first voltage applying circuit, a second voltage applying circuit, and a switch controller. The first voltage applying circuit includes a first DC power source for applying a positive polarity voltage across an electrode gap, and a first switch for on/off-switching of application of the positive polarity voltage. The second voltage applying circuit includes a second DC power source for applying a reverse polarity voltage to the electrode gap, and a second switch for on/off-switching of application of the reverse polarity voltage. The switch controller controls the first switch and the second switch so that the first switch and the second switch are not turned on simultaneously. The first DC power source and the second DC power source are set up so that the absolute value of the reverse polarity voltage is lower than the absolute value of the positive polarity voltage.

A wire-cut EDM machine in which the position of the liquid level of machining fluid is adjusted at the time of automatic wire threading includes a shape information acquisition unit for acquiring information on the shape of an object to be machined, a wire-threading position information acquisition unit for acquiring information on a wire-threading position of a wire electrode based on relative positions of upper and lower wire guides, and a liquid level position adjustment unit for acquiring the height of the object to be machined in the vicinity of the wire-threading position based on the information on the shape of the object to be machined and adjusting the position of the liquid level of the machining fluid at the time of automatic wire threading.

A wire-cut EDM machine in which the position of the liquid level of machining fluid is adjusted at the time of automatic wire threading includes a shape information acquisition unit for acquiring information on the shape of an object to be machined, a wire-threading position information acquisition unit for acquiring information on a wire-threading position of a wire electrode based on relative positions of upper and lower wire guides, and a liquid level position adjustment unit for acquiring the height of the object to be machined in the vicinity of the wire-threading position based on the information on the shape of the object to be machined and adjusting the position of the liquid level of the machining fluid at the time of automatic wire threading.