A wire electrical discharge machine includes: a mounting table having a placement plane on which a workpiece can be placed; a first guide portion and a second guide portion for stretching a wire electrode therebetween. The first guide portion is integrally equipped with a probe. The relative position in the placement plane between the probe detecting its abutment with the workpiece and the first guide portion before moving the relative position between the first guide portion and the second guide portion is stored as an offset. This offset is corrected based on the tilt information indicating the tilt state of the workpiece relative to the placement plane. Thus, it is possible to obtain the corrected offset in accordance with the tilt state of the workpiece after changing the relative position between the first guide portion and the second guide portion.

A wire electrical discharge machine obtains position error information indicating a position error in a planar direction in a workpiece placed on a mounting table after relative positions between a first guide unit and a second guide unit are changed, and calculates a position of the workpiece with the corrected position error in the planar direction in a state where a wire electrode is inclined according to an inclined state of the workpiece by using this position error information.

A wire electrical discharge machining apparatus includes an NC control device, and the NC control device determines, during taper machining, whether the type of machining is a type (first type) in which an upper die is located on a workpiece side in comparison with a lower die or a type (second type) in which the upper die is located on the side opposite to the workpiece in comparison with the lower die on the basis of a machining program and corrects the positional relationship between the upper die and the lower die in accordance with the determined type of machining.

A wire electrical discharge machining apparatus includes an NC control device, and the NC control device determines, during taper machining, whether the type of machining is a type (first type) in which an upper die is located on a workpiece side in comparison with a lower die or a type (second type) in which the upper die is located on the side opposite to the workpiece in comparison with the lower die on the basis of a machining program and corrects the positional relationship between the upper die and the lower die in accordance with the determined type of machining.

In wire-electrical discharge machine and a numerical control apparatus thereof and a numerical control apparatus for controlling a machine tool, optional minute blocks are automatically created in front of and behind a connecting point, i.e., a joint of a block to which an offset command is instructed, and an offset value is exchanged between the minute blocks so that a correct offset value is set in a desired block.

In wire-electrical discharge machine and a numerical control apparatus thereof and a numerical control apparatus for controlling a machine tool, optional minute blocks are automatically created in front of and behind a connecting point, i.e., a joint of a block to which an offset command is instructed, and an offset value is exchanged between the minute blocks so that a correct offset value is set in a desired block.

In wire-electrical discharge machine and a numerical control apparatus thereof and a numerical control apparatus for controlling a machine tool, optional minute blocks are automatically created in front of and behind a connecting point, i.e., a joint of a block to which an offset command is instructed, and an offset value is exchanged between the minute blocks so that a correct offset value is set in a desired block.

In wire-electrical discharge machine and a numerical control apparatus thereof and a numerical control apparatus for controlling a machine tool, optional minute blocks are automatically created in front of and behind a connecting point, i.e., a joint of a block to which an offset command is instructed, and an offset value is exchanged between the minute blocks so that a correct offset value is set in a desired block.

An EDM machine includes a machine head, a wire guide, a machining wire extending from the wire guide to the machine head, a rotary table mounted to a first surface and a fixed table mounted to the rotary table, and a fixture mounted to the fixed table. The fixture includes a mounting portion substantially circumscribing the fixture. The mounting portion further includes a mounting surface. The mounting surface is closer to a first surface than an upper surface of the fixed table.

A wire electric-discharge machining device includes a control unit that selects a cutting wire to which a pulse voltage is applied by a pulse-voltage generation unit on a basis of an angle formed between an end face of a workpiece and a plane including a plurality of cutting wires, which are not parallel to the end face, an interval between parallel cutting wires, and a relative distance between the cutting wires and the workpiece. A drive unit drives a workpiece in a direction not vertical to the plane including the cutting wires, and the workpiece is cut by electric-discharge machining by applying a pulse voltage.