JPH06143038A - Wire electrode for electric discharge machining - Google Patents

Abstract

PURPOSE:To exhaust a molten metal generated by a discharge easily, and to improve the processing speed, in a wire electrode for wire electric discharge machining. CONSTITUTION:A wire with a poligonal section such as a square wire is twisted to form into a wire electrode 1. In such a wire electrode 1, recesses 1c are formed to the parts corresponding to the sides of the square in the raw material condition in the screw form grooves by the twisting. A molten metal generated by the discharge is accumulated to the recesses 1c, and it is exhausted to the outer side following the feeding of the wire electrode 1. Furthermore, this wire electrode 1 is opposed to a work in the running condition as a circular electrode, and an accurate discharge machining can be carried out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric discharge machining wire electrode used as a machining electrode for a wire cut electric discharge machine.

[0002]

2. Description of the Related Art FIG. 8 is an external view showing the shape of a conventional wire electrode used in an electric discharge machine, and FIG. 9 is a sectional view thereof. Further, FIG. 10 is a diagram showing a machining principle of wire electric discharge machining. In these figures, 11 is a wire electrode which is a processing electrode, and has an elongated round wire shape having a circular cross section. 12 is a work piece surrounding the wire electrode 11,
When the longitudinal direction of the wire electrode 11 is the Z axis, it is sent in the X and Y axis directions. Reference numeral 13 is the workpiece 12 and the wire electrode 1
It is ion-exchanged water that is placed between 1 and 1.

The wire electrode 11 has a columnar shape. When performing electric discharge machining, the wire electrode 11 is brought closer to the workpiece 12 from the Z-axis direction, and the wire electrode 11 is surrounded by ion exchange having a large insulation resistance. Continue running water 13. Then, a voltage is applied between the wire electrode 11 and the workpiece 12, and the ion-exchanged water 13 is used as a medium to cause discharge.

The above-mentioned discharge is caused by the wire electrode 11 and the workpiece 1.
The arc column passes through the shortest distance between the two, and the heat energy locally heats both surfaces of the wire electrode 11 and the workpiece 12 to a molten state. At the same time, the ion-exchanged water 13 around the wire electrode 11 is rapidly heated to be in a vaporized state, and is rapidly expanded to be in a locally explosive state.

The pressure of this explosion blows off the molten metal to form fine metal particles, which are carried away together with the ion-exchanged water 13. Then the work piece 1
Both surfaces of the wire electrode 2 and the wire electrode 11 are cooled by the ion-exchanged water 13, leaving a recess.

[0006] By repeating such electric discharge and metal removal very rapidly and frequently, a large dent is gradually enlarged on the surface of the workpiece 12. Then, by feeding the wire electrode 11 according to the expansion speed, a groove is formed along the shape of the wire electrode 11, and desired electric discharge machining can be performed.

[0007]

The conventional wire electrode for electric discharge machining has a cylindrical surface shape as described above,
The molten metal generated by the electric discharge is released to the outside by the explosive pressure of water, but the gap between the work piece and the work piece is usually about 10 to 30 μm, and the work piece thickness is usually 10 to 250 μm.
mm, and the metal particles are discharged only by water through a thin hole between the workpiece and the workpiece. For this reason,
During electrical discharge machining, metal particles narrow the electrical discharge gap between the workpiece and
There is a problem that a short circuit occurs and the processing speed is limited.

The present invention has been made in order to solve the above problems, and an object thereof is to obtain a wire electrode for electric discharge machining in which molten metal generated by electric discharge can be easily discharged and a machining speed is improved. I am trying.

[0009]

The electric discharge machining wire electrode according to the present invention is constructed as follows.

(1) A wire electrode used in an electric discharge machine, which is formed by twisting a metal square wire having a polygonal cross section.

(2) A wire electrode used in an electric discharge machine, in which a plurality of metal rectangular wires having a polygonal cross section are bundled together,
This was twisted and formed.

(3) A wire electrode used in an electric discharge machine, in which one or a plurality of grooves continuous in the axial direction are provided on the surface of a metal round wire having a circular cross section, and the groove is formed by twisting the groove. did.

(4) A wire electrode used in an electric discharge machine, which is formed by binding a plurality of metal round wires having a circular cross section and twisting the wires.

(5) A wire electrode used in an electric discharge machine, in which one or more grooves continuous in the axial direction are provided on the surface of a round metal wire having a circular cross section, and a plurality of these are bound together. , Was further twisted and formed.

[0015]

In the electric discharge machining wire electrode of the present invention,
Since it is formed by twisting a polygonal cross-section polygonal line or a circular cross-section round line, a recess is provided as an escape route for the metal particles melted by the discharge, and the discharge interval is not narrowed.

[0016]

【Example】

Example 1. 1 is an external view showing a wire electrode for electric discharge machining according to a first embodiment of the present invention, and FIG. 2 is a sectional view thereof. In FIGS. 1 and 2, reference numeral 1 denotes a wire electrode which is a machining electrode for wire chip electric discharge machining, and twists (twists) a square wire made of a metal (including an alloy) having a polygonal cross section (here, a square). Has been formed. Reference numerals 1a and 1b denote corners and surface portions of the square wire, and 1c denotes a concave portion generated by twisting, and the diameter of the envelope after twisting is the same as the diagonal dimension of the square wire before twisting.

The wire electrode 1 constructed as described above is
Since it travels in the axial direction as a whole, the outer diameter shape is circular as if it were a round wire, and the workpiece 12 in FIG.
The groove dimension machined therein can maintain a constant value, and since the recess 1c is provided on the surface of the wire electrode 1, the molten metal particles generated by the discharge are held in the recess 1c. You can send it as it is.

That is, by twisting a wire having a non-circular cross section, a recess 1c is obtained which serves as a chip escape path capable of holding metal particles melted by discharge without narrowing the discharge gap, and the wire electrode 1 runs. Therefore, the outer shape of the wire electrode 1 after twisting may be considered to be circular. In this way, the operation of discharging the molten metal particles while providing a uniform discharge gap can be achieved by a simple means of twisting, and the processing speed is improved.

When electric discharge machining is performed using the wire electrode 1, the molten metal generated by the electric discharge is discharged by the ion exchanged water 13 when the electric discharge is scattered by the explosion of the ion exchanged water 13. , Wire electrode 1
While being held in the concave portion 1c on the surface of the wire, the wire electrode 1 and the wire electrode 1 are sent to the outside of the workpiece 12. Therefore, the discharge gap is made uniform and stable, the occurrence of short circuit is reduced, and the processing speed is increased.

Example 2. 3 is an external view showing a second embodiment of the present invention, and FIG. 4 is a sectional view thereof. The wire electrode 2 of this embodiment has a polygonal (square) cross section element wire 3.
A plurality of (four in this case) four and five are bound together and twisted to form. In the figure, 2a and 2b are corner portions and surface portions of the square wire, and 2c is a concave portion generated by twisting.

The wire electrode 2 constructed as described above is
Since it is twisted in the same manner as in the above-described embodiment, the concave portion 2c having a half value of the diagonal dimension and the opposite side dimension or the difference between the maximum diameter and the minimum diameter of the cross section of the element wires 3, 4, and 5 before the twist. After twisting, the wire electrodes 2 are continuously formed at the twisting pitch on the surface of the wire electrode 2. At the same time, since it is twisted, the diagonal part and the maximum diameter part are evenly distributed around the wire electrode 2.
The discharge gap is always kept constant on average even if the wire electrode 2 is twisted or rotated when the workpiece is fed in the thickness direction. Therefore, good wire electric discharge machining can be performed, and the machining speed is also improved.

Example 3. FIG. 5 is a sectional view showing a third embodiment of the present invention. The wire electrode 6 of this embodiment is formed by twisting a square wire having a hexagonal cross section,
b shows the corner | angular part and surface part of a square line, respectively.

Even with such a structure, since the concave portion is formed by twisting, the molten metal particles can be carried out through the concave portion, and the same operation as that of each of the above-described embodiments can be achieved with a simple structure. The effect is obtained.

Example 4. FIG. 6 is a sectional view showing a fourth embodiment of the present invention. The wire electrode 7 of this embodiment is formed by twisting a round wire having a chrysanthemum cross section, and a plurality of axially continuous grooves 7b are provided on the surface of the round wire having a circular cross section, and the groove 7b is twisted. It has been done. 7a is a convex portion between the grooves 7b.

In the wire electrode 7 described above, a recess is formed around the groove 7b by twisting, whereby the molten metal can be easily discharged and the processing speed can be improved.

Example 5. FIG. 7 is a sectional view showing a fifth embodiment of the present invention. The wire electrode 8 of this embodiment is formed by binding a plurality of round wires (here, three) having a circular cross section and twisting the wires.

Even with such a structure, since the concave portion serving as an escape route for the molten metal particles generated by the discharge is formed,
It is possible to obtain the same effect as that of each of the above-described embodiments.
Even in this case, as in the embodiment of FIG. 6, grooves may be provided on the surface of each round wire so as to be continuous in the axial direction, and the discharge of the molten metal particles can be further promoted.

[0028]

As described above, according to the present invention, one or a plurality of polygonal cross-section polygonal lines or circular cross-section circular lines are twisted to form a metal melted by electric discharge with a simple structure. Since the recesses serving as escape paths for the grains are formed, the molten metal can be easily discharged, the discharge interval is not narrowed, and the processing speed is improved.

[Brief description of drawings]

FIG. 1 is an outline view showing a first embodiment of the present invention.

2 is a cross-sectional view of the wire electrode of FIG.

FIG. 3 is an external view showing a second embodiment of the present invention.

4 is a cross-sectional view of the wire electrode of FIG.

FIG. 5 is a sectional view showing a third embodiment of the present invention.

FIG. 6 is a sectional view showing a fourth embodiment of the present invention.

FIG. 7 is a sectional view showing a fifth embodiment of the present invention.

FIG. 8 is an external view showing a conventional example.

9 is a cross-sectional view of the wire electrode of FIG.

FIG. 10 is an explanatory diagram showing a processing principle of wire electric discharge machining.

[Explanation of symbols]

 1 Wire Electrode 2 Wire Electrode 3 Elemental Wire 4 Elemental Wire 5 Elemental Wire 6 Wire Electrode 7 Wire Electrode 7b Groove 8 Wire Electrode

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[Procedure amendment]

[Submission date] February 17, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction content]

[0016]

EXAMPLES Example 1. 1 is an external view showing a wire electrode for electric discharge machining according to a first embodiment of the present invention, and FIG. 2 is a sectional view thereof. In FIGS. 1 and 2, reference numeral 1 denotes a wire electrode which is a machining electrode for wire- cut electric discharge machining, and twists (twists) a square wire made of a metal (including an alloy) having a polygonal cross section (here, a square). Has been formed. Reference numerals 1a and 1b denote corners and surface portions of the square wire, and 1c denotes a concave portion generated by twisting, and the diameter of the envelope after twisting is the same as the diagonal dimension of the square wire before twisting.

Claims (5)

[Claims] 1. A wire electrode used in an electric discharge machine, wherein the wire electrode is formed by twisting a square metal wire having a polygonal cross section. 2. A wire electrode for use in an electric discharge machine, comprising a plurality of metal rectangular wires having a polygonal cross section bound together and twisted to form a wire electrode. 3. A wire electrode used in an electric discharge machine, wherein one or more grooves continuous in the axial direction are provided on the surface of a metal round wire having a circular cross section, and the groove is formed by twisting the groove. A wire electrode for electric discharge machining characterized in that 4. A wire electrode for use in an electric discharge machine, comprising a plurality of metal round wires having a circular cross section bound together and twisted to form the wire electrode. 5. A wire electrode used in an electric discharge machine, wherein one or a plurality of grooves continuous in the axial direction are provided on the surface of a round wire made of a metal having a circular cross section, and a plurality of these are bound together.
A wire electrode for electric discharge machining, which is formed by further twisting.