WIRE ELECTRIC DISCHARGE MACHINE HAVING CORNER SHAPE CORRECTING FUNCTION

• US 20160136745A1
• Filed: 11/12/2015
• Published: 05/19/2016
• Est. Priority Date: 11/19/2014
• Status: Active Grant

• Current Assignee: Fanuc Corporation
• Original Assignee: Fanuc Corporation
• Inventors: HASEGAWA, Yasuo
• Granted Patent: US 10,307,847 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B23H 1/02 Electric circuits specially adapted therefor, e.g. power supply, control, preventing short circuits or other abnormal discharges
• CPC Class Codes: B23H 7/065 Electric circuits specially adapted therefor
• CPC Class Codes: B23H 7/08 Wire electrodes
• CPC Class Codes: B23H 7/20 for programme-control, e.g. adaptive programme-control systems in general G05B19/00
• CPC Class Codes: B23H 7/26 Apparatus for moving or positioning electrode relatively to workpiece; Mounting of electrode
• CPC Class Codes: G05B 2219/45043 EDM machine, wire cutting

Abstract

A wire electric discharge machine has a function of performing correction of corner shapes independently on an upper surface and a lower surface of workpiece. On the basis of the positions of upper and lower wire guides and the position and the thickness of the workpiece, the wire electric discharge machine calculates, on the upper and lower surfaces of the workpiece, a shape correction amount in a state in which there is a space between the upper nozzle and the upper surface of the workpiece and also in which there is a space between the lower nozzle and the lower surface of the workpiece, from a correction amount at the time when nozzles of the upper and lower wire guides are closely attached to the upper and lower surfaces of the workpiece. The wire electric discharge machine performs shape correction according to the calculated shape correction amount.

Claims

1. A wire electric discharge machine that stretches a wire electrode between upper and lower wire guides and relatively moves the wire electrode with respect to a workpiece on the basis of a machining program in order to perform electric discharge machining, the wire electric discharge machine comprising:

a reference-position storing unit configured to store, as a reference position, relative positions in a workpiece thickness direction of the upper and lower wire guides with respect to workpiece upper and lower surfaces and thickness of the workpiece in a state in which the upper and lower wire guides respectively approach the upper and lower surfaces of the workpiece;

a correction-amount storing unit configured to store correction amounts for correcting shift amounts between wire guide coordinate positions on a machining program route in the reference position and actual machining positions on the workpiece upper and lower surfaces, with the shift being caused by wire bending during machining;

a setting unit configured to set relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces in any upper and lower wire guide positions and the thickness of the workpiece;

a correction-amount calculating unit configured to calculate, on the basis of the reference position stored in the reference-position storing unit and the correction amounts stored in the correction-amount storing unit, correction amounts for correcting the respective shift amounts in the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces and the thickness of the workpiece set by the setting unit; and

a wire-guide-position correcting unit configured to correct, on the basis of the correction amounts calculated by the correction-amount calculating unit, positions of the upper and lower wire guides in a relative movement command of a wire guide with respect to the workpiece commanded by the machining program, independently in an upper guide section and lower guide section.

2. A wire electric discharge machine that stretches a wire electrode between upper and lower wire guides and relatively moves the wire electrode with respect to a workpiece on the basis of a machining program in order to perform electric discharge machining, the wire electric discharge machine comprising:

a reference-position storing unit configured to store, as reference positions, a plurality of sets of relative positions in a workpiece thickness direction of the upper and lower wire guides with respect to workpiece upper and lower surfaces and thickness of the workpiece;

a correction-amount storing unit configured to store correction amounts for correcting shift amounts between wire guide coordinate positions on a machining program route in a plurality of the reference positions and actual machining positions on the workpiece upper and lower surfaces, with the shift being caused by wire bending during machining;

a setting unit configured to set relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces in any upper and lower wire guide positions and the thickness of the workpiece;

a selecting unit configured to select, from the sets of the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces and the thickness of the workpiece stored in the reference-position storing unit, a plurality of sets of those close to the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces and the thickness of the workpiece set by the setting unit;

a correction-amount calculating unit configured to calculate, on the basis of the plurality of reference positions in the plurality of sets selected by the selecting unit and the correction amounts stored in the correction-amount storing unit, correction amounts for correcting the respective shift amounts in the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces and the thickness of the workpiece set by the setting unit; and

a wire-guide-position correcting unit configured to correct, on the basis of the correction amounts calculated by the correction-amount calculating unit, positions of the upper and lower wire guides in a relative movement command of a wire guide with respect to the workpiece commanded by the machining program, independently in an upper guide section and a lower guide section.

3. A wire electric discharge machine that stretches a wire electrode between upper and lower wire guides and relatively moves the wire electrode with respect to a workpiece on the basis of a machining program in order to perform electric discharge machining, the wire electric discharge machine comprising:

a reference-position storing unit configured to store, as reference positions, a plurality of sets of relative positions in workpiece thickness direction of the upper and lower wire guides with respect to workpiece upper and lower surfaces and thickness of the workpiece;

a correction-amount storing unit configured to store correction amounts for correcting shift amounts between wire guide coordinate positions on a machining program route in a plurality of the reference positions and actual machining positions on the workpiece upper and lower surfaces, with the shift being caused by wire bending during machining;

a setting unit configured to set relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces in any upper and lower wire guide positions and the thickness of the workpiece;

a correction-amount invoking unit configured to invoke, from the plurality of reference positions stored in the reference-position storing unit and the correction amounts stored in the correction-amount storing unit, correction amounts for correcting the respective shift amounts in the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces and the thickness of the workpiece set by the setting unit; and

a wire-guide-position correcting unit configured to correct, on the basis of the correction amounts invoked by the correction-amount invoking unit, positions of the upper and lower wire guides in a relative movement command of a wire guide with respect to the workpiece commanded by the machining program, independently in an upper guide section and a lower guide section.

4. A wire electric discharge machine that stretches a wire electrode between upper and lower wire guides and relatively moves the wire electrode with respect to a workpiece on the basis of a machining program in order to perform electric discharge machining, the wire electric discharge machine comprising:

a reference-position storing unit configured to store, as a reference position, relative positions in a workpiece thickness direction of the upper and lower wire guides with respect to workpiece upper and lower surfaces and thickness of the workpiece in a state in which the upper and lower wire guides respectively approach the upper and lower surfaces of the workpiece;

a shift-amount storing unit configured to store shift amounts between wire guide coordinate positions on a machining program route in the reference position and actual machining positions on the workpiece upper and lower surfaces, with the shift being caused by wire bending during machining;

a correction-amount calculating unit configured to calculate correction amounts from the shift amounts stored in the shift-amount storing unit;

a setting unit configured to set relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces in any upper and lower wire guide positions and the thickness of the workpiece;

a correction-amount calculating unit configured to calculate, on the basis of the reference position stored in the reference-position storing unit and the correction amounts calculated by the correction-amount calculating unit, correction amounts for correcting the respective shift amounts in the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces and the thickness of the workpiece set by the setting unit; and

a wire-guide-position correcting unit configured to correct, on the basis of the correction amounts calculated by the correction-amount calculating unit, positions of the upper and lower wire guides in a relative movement command of a wire guide with respect to the workpiece commanded by the machining program, independently in an upper guide section and a lower guide section.

5. A wire electric discharge machine that stretches a wire electrode between upper and lower wire guides and relatively moves the wire electrode with respect to a workpiece on the basis of a machining program in order to perform electric discharge machining, the wire electric discharge machine comprising:

a reference-position storing unit configured to store, as reference positions, a plurality of sets of relative positions in a workpiece thickness direction of the upper and lower wire guides with respect to workpiece upper and lower surfaces and thickness of the workpiece;

a shift-amount storing unit configured to store shift amounts between wire guide coordinate positions on a machining program route in a plurality of the reference positions and actual machining positions on the workpiece upper and lower surfaces, with the shift being caused by wire bending during machining;

a correction-amount calculating unit configured to calculate correction amounts from the shift amounts stored in the shift-amount storing unit;

a setting unit configured to set relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces in any upper and lower wire guide positions and the thickness of the workpiece;

a selecting unit configured to select, from the sets of the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces and the thickness of the workpiece stored in the reference-position storing unit, a plurality of sets of those close to the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces and the thickness of the workpiece set by the setting unit;

a correction-amount calculating unit configured to calculate, on the basis of the plurality of reference positions in the plurality of sets selected by the selecting unit and the correction amounts stored in the correction-amount storing unit, correction amounts for correcting the respective shift amounts in the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces and the thickness of the workpiece set by the setting unit; and

a wire-guide-position correcting unit configured to correct, on the basis of the correction amounts calculated by the correction-amount calculating unit, positions of the upper and lower wire guides in a relative movement command of a wire guide with respect to the workpiece commanded by the machining program, independently in an upper guide section and a lower guide section.

6. A wire electric discharge machine that stretches a wire electrode between upper and lower wire guides and relatively moves the wire electrode with respect to a workpiece on the basis of a machining program in order to perform electric discharge machining, the wire electric discharge machine comprising:

a reference-position storing unit configured to store, as reference positions, a plurality of sets of relative positions in workpiece thickness direction of the upper and lower wire guides with respect to workpiece upper and lower surfaces and thickness of the workpiece;

a shift-amount storing unit configured to store shift amounts between wire guide coordinate positions on a machining program route in a plurality of the reference positions and actual machining positions on the workpiece upper and lower surfaces, with the shift being caused by wire bending during machining;

a correction-amount calculating unit configured to calculate correction amounts from the shift amounts stored in the shift-amount storing unit;

a setting unit configured to set relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces in any upper and lower wire guide positions and the thickness of the workpiece;

a correction-amount invoking unit configured to invoke, from the plurality of reference positions stored in the reference-position storing unit and the correction amounts calculated by the correction-amount calculating unit, correction amounts for correcting the respective shift amounts in the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces and the thickness of the workpiece set by the setting unit; and

a wire-guide-position correcting unit configured to correct, on the basis of the correction amounts invoked by the correction-amount invoking unit, positions of the upper and lower wire guides in a relative movement command of a wire guide with respect to the workpiece commanded by the machining program, independently in an upper guide section and a lower guide section.

7. The wire electric discharge machine according to claim 1, wherein the reference-position storing unit is configured to store a plurality of sets of the positions of the upper and lower wire guides and the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces, instead of storing the plurality of sets of the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces.

8. The wire electric discharge machine according to claim 2, wherein the reference-position storing unit is configured to store a plurality of sets of the positions of the upper and lower wire guides and the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces, instead of storing the plurality of sets of the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces.

9. The wire electric discharge machine according to claim 3, wherein the reference-position storing unit is configured to store a plurality of sets of the positions of the upper and lower wire guides and the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces, instead of storing the plurality of sets of the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces.

10. The wire electric discharge machine according to claim 4, wherein the reference-position storing unit is configured to store a plurality of sets of the positions of the upper and lower wire guides and the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces, instead of storing the plurality of sets of the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces.

11. The wire electric discharge machine according to claim 5, wherein the reference-position storing unit is configured to store a plurality of sets of the positions of the upper and lower wire guides and the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces, instead of storing the plurality of sets of the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces.

12. The wire electric discharge machine according to claim 6, wherein the reference-position storing unit is configured to store a plurality of sets of the positions of the upper and lower wire guides and the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces, instead of storing the plurality of sets of the relative positions in the workpiece thickness direction of the upper and lower wire guides with respect to the workpiece upper and lower surfaces.