Wire electrical discharge machine and wire electrical discharge machining method

Patent metadata

Field	Value
Publication number	US-10427233-B2
Application number	US-201715659978-A
Country	US
Kind code	B2
Filing date	Jul 26, 2017
Priority date	Jul 27, 2016
Publication date	Oct 1, 2019
Grant date	Oct 1, 2019

Abstract

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.

First claim

What is claimed is:

1. A wire electrical discharge machine, comprising:
a mounting table having a placement plane on which a workpiece is to be placed, wherein a three-axis coordinate system is defined by (i) an XY-plane coinciding with the placement plane and (ii) a normal direction of the placement plane;
a first guide portion and second guide portion configured to support and stretch a wire electrode therebetween, wherein the workpiece is subjected to electrical discharge machining under a condition where a relative position between the first guide portion and the second guide portion is changed so as to align an inclination of the wire electrode with a tilt of the workpiece relative to the placement plane;
a probe configured to be movable integrally with the first guide portion and detect abutment against the workpiece placed on the mounting table;
an offset storage configured to store, as an offset, a relative position in the XY-plane between the first guide portion and the probe that is in a detected position of abutment against the workpiece before the relative position between the first guide portion and the second guide portion is changed; and
a controller including a processor and a memory, the controller configured to
acquire tilt information representing a tilt state of the workpiece with respect to the placement plane, and
correct the offset stored in the offset storage based on the acquired tilt information to obtain an offset corresponding to the tilt state of the workpiece after the relative position between the first guide portion and the second guide portion is changed.

2. The wire electrical discharge machine according to claim 1 , wherein
the controller is configured to
acquire a relative position in the normal direction between the probe and the first guide portion, and
correct the stored offset based on (i) a tilt angle of the workpiece as the tilt information and on (ii) the acquired relative position in the normal direction between the probe and the first guide portion.

3. The wire electrical discharge machine according to claim 2 , wherein
the controller is configured to acquire the relative position in the normal direction between the probe and the first guide portion by correcting a position of the first guide portion in the normal direction in accordance with a size of a sensor of the probe.

4. The wire electrical discharge machine according to claim 2 , wherein
the controller is configured to correct the stored offset in accordance with a size of a sensor of the probe.

5. The wire electrical discharge machine according to claim 1 , wherein
the controller is configured to
acquire at least two relative positions in the normal direction between the probe, the first guide portion, and the second guide portion, and
correct the stored offset based on (i) an amount of movement of a position of the second guide portion as the tilt information and (ii) the acquired at least two relative positions.

6. The wire electrical discharge machine according to claim 5 , wherein
the controller is configured to acquire the relative position in the normal direction between the probe and the first guide portion by correcting a position of the first guide portion in the normal direction in accordance with a size of a sensor of the probe.

7. The wire electrical discharge machine according to claim 5 , wherein
the controller is configured to correct the stored offset in accordance with a size of a sensor of the probe.

8. A wire electrical discharge machining method using a wire electrical discharge machine that includes:
a mounting table having a placement plane on which a workpiece is to be placed, wherein a three-axis coordinate system is defined by (i) an XY-plane coinciding with the placement plane and (ii) a normal direction of the placement plane;
a first guide portion and second guide portion that support and stretch a wire electrode therebetween, wherein the workpiece is subjected to electrical discharge machining under a condition where a relative position between the first guide portion and the second guide portion is changed so as to align an inclination of the wire electrode with a tilt of the workpiece with respect to the placement plane;
a probe configured to be movable integrally with the first guide portion and detect abutment against the workpiece placed on the mounting table; and
a controller,
the wire electrical discharge machining method comprising:
storing, in an offset storage, as an offset, a relative position in the XY-plane between the first guide portion and the probe that is in a detected position of abutment against the workpiece before the relative position between the first guide portion and the second guide portion is changed;
acquiring, by the controller, tilt information representing a tilt state of the workpiece with respect to the placement plane; and
correcting, by the controller, the stored offset based on the acquired tilt information to obtain an offset corresponding to the tilt state of the workpiece after the relative position between the first guide portion and the second guide portion is changed.

9. The wire electrical discharge machining method according to claim 8 , further comprising:
acquiring, by the controller, a relative position in the normal direction between the probe and the first guide portion,
wherein, in the correcting, the stored offset is corrected based on (i) a tilt angle of the workpiece as the tilt information and (ii) the acquired relative position in the normal direction between the probe and the first guide portion.

10. The wire electrical discharge machining method according to claim 9 , wherein
the relative position in the normal direction between the probe and the first guide portion is acquired by correcting, by the controller, the position of the first guide portion in the normal direction in accordance with a size of a sensor of the probe.

11. The wire electrical discharge machining method according to claim 9 , wherein
in the correcting, the stored offset is corrected in accordance with a size of a sensor of the probe.

12. The wire electrical discharge machining method according to claim 8 , further comprising:
acquiring, by the controller, at least two relative positions in the normal direction between the probe, the first guide portion, and the second guide portion,
wherein, in the correcting, the stored offset is corrected based on (i) an amount of movement of a position of the second guide portion as the tilt information and (ii) the acquired at least two relative positions.

13. The wire electrical discharge machining method according to claim 12 , wherein
the relative position in the normal direction between the probe and the first guide portion is acquired by correcting, by the controller, the position of the first guide portion in the normal direction in accordance with a size of a sensor of the probe.

14. The wire electrical discharge machining method according to claim 12 , wherein
in the correcting, the stored offset is corrected in accordance with a size of a sensor of the probe.

Assignees

• Fanuc Corp

Inventors

• Ookubo Kousuke
• Irie Shouta

Classifications

• B23H7/101

  Supply of working media · CPC title

• B23H7/20

  for program control, e.g. adaptive · CPC title

• B23H2500/20

  Methods or devices for detecting wire or workpiece position · CPC title

• B23H7/10 Primary

  Supporting, winding or electrical connection of wire-electrode · CPC title

• G05B2219/45043

  EDM machine, wire cutting · CPC title