JPS6228122A - Wire electrode for wire cut electric discharge machine - Google Patents

Abstract

PURPOSE:To sharply cut a corner part by an electrode with no necessity for decreasing its sectional area, by forming a section of the wire electrode in a different shape, for instance, having an angular part. CONSTITUTION:A wire electrode 1 forms its section in a different shape so as to provide an angular part (for instance, rectangular, triangular and flat shape). In this way, a machine, enabling a corner part to be sharply finished by the wire electrode 1 with no necessity for decreasing its sectional area, can perform high accurate machining even if the machine uses a low-priced wire of small strength.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention uses a thin metal wire as an electrode and applies a tensile force to the wire, and while the wire is being fed, the workpiece and the electrode wire are connected to each other. The present invention relates to a wire for a wire-cut electrical discharge machine that generates electrical discharge between the wires and processes a workpiece using the electrical discharge energy.

[Conventional technology]

Wires that are electrodes in wire-cut electric discharge machines (hereinafter referred to as wire electrodes) are usually made of copper or brass wire drawn into a circular cross section with a diameter of 0.05 mm to 0.25 mm.
= m is used depending on conditions such as the thickness of the workpiece. There are also tungsten products, but they are dozens of times more expensive than the copper and brass products mentioned above.
Used only for special purposes.

4 and 5 are enlarged schematic diagrams showing a state in which a workpiece is being processed by a wire electrode, and FIG. 4 is a cross section taken along the line AA in FIG. 5. In the figure, (1) is a wire electrode, (2) is a workpiece, and (2a) is a workpiece (2
), (2b) is the cut-off part, (3) is the discharge part between the wire electrode (1) and the workpiece (2), (4)
is the trajectory of the wire electrode (1) with respect to the workpiece (2), (
5) is a pulse power source that applies a discharge voltage between the wire electrode (1) and the workpiece (2), and (6) is the electrode that feeds the wire (1).
The corner portion of the power supply plate (7) is in contact with the .

In the electrode (1) and workpiece (2) configured as described above, for example, the electrode (1) fed from above is connected to the workpiece (2) via the power supply plate (6). Since a pulse voltage is applied to , a pulse family t is generated through the cooling water in the discharge part (3), and the workpiece (2) is melted by the energy of this discharge and follows the trajectory (4).
The straight part has a cutting width of (d+2g), and the corner part (7) has a cutting width of (
It is processed by forming a corner R of Σ0g).

[Problem that the invention seeks to solve]

In the conventional electrical discharge machining using a wire electrode as described above, the corner part (7) of the product part (2a) of the workpiece (2) after cutting is the radius (d/2) of the wire electrode (1) and the discharge The value (a/2 +
g) Corner R will be formed, so depending on the conditions required for the product after cutting, it may be necessary to remove this corner R. Especially if the product obtained after cutting is made of a hard thick plate such as a mold. In such cases, this removal work must be done manually and take a considerable amount of time.

In order to save this removal work as much as possible, corner R'
(!: If a thin electrode wire (1) is used so that the remaining part is small, the capacity of the discharge current will be small, so the machining speed must be slowed down.Alternatively, the machining speed must be slowed down because it is cheap.) There were problems such as having to use expensive tungsten-based or molybdenum-based wire electrodes for microfabrication, which have excellent strength, instead of copper or brass-based wire electrodes.

This invention was made to solve this problem, and aims to obtain an electrode wire that can be cut with almost no corner radius at the cutting part without using a thin electrode wire. .

[Means to solve all problems]

The wire electrode according to the present invention is formed to have an irregular cross section that allows sharp cutting at corners without reducing the efficiency of electrical discharge machining.

[Effect]

In this invention, wire electric KIjL, t corner R
Since the cross-sectional shape is such that it cannot be completely formed, electrical discharge machining is performed following this cross-sectional shape with a small discharge gap (g) of about several tens of microns in between, so the corners are cut into sharp shapes. do.

〔Example〕

FIG. 1 is a schematic diagram showing the state of processing using an electrode wire according to an embodiment of the present invention, (1) to (4).

(7) is the same or corresponding part to the same reference numeral in FIG. 5 showing the conventional example, and the wire electrode (1) according to the present invention is
It is formed into a rectangular cross section with the lengths of each side being (a) and (b).

Next, the entire machining operation using this wire electrode (1) will be explained. The cutting progresses from the bottom in the figure according to the trajectory (4), and when the center of the wire electrode (1) reaches the 0 point while cutting at cutting 'Wit (a + 2 g), the workpiece (2) The corner part (7) of the product part (2a) is
The discharge part (3) follows the shape of the square wire electrode (1).
The cooling water inside the wire is used as a medium to cut the wire across the discharge gap (g), resulting in a sharp corner shape. Cutting that produces sharp corners is possible without reducing the cross-sectional area of the electrode. In other words, there is no need to use a wire with a small cross-sectional area, which was done in the past to reduce the corner R. For example, even if the cross-sectional shape of the wire is changed, the wire electrode (1) with the same area can be used. This allows machining to obtain sharp corner shapes without reducing factors that affect machining efficiency, such as discharge current capacity and wire tension.

In the above embodiment, the case where the cross section of the wire is square has been described, but the wire may have a triangular cross section as shown in Fig. 2, or it may have a flat shape as shown in Fig. 6. As in the embodiment, sharp corners can be machined without reducing machining efficiency.

〔Effect of the invention〕

As described above, this invention is configured so that electrical discharge machining is performed on a workpiece with a cutting pattern that requires corner machining using a wire electrode with an irregular cross section, so that sharp corners can be machined without reducing machining efficiency. There are effects that can be done.

[Brief explanation of the drawing]

1 is a schematic diagram showing a machining state using a wire electrode according to one embodiment of the present invention, FIGS. 2 and 3 are schematic diagrams showing a machining state using a wire electrode according to another embodiment of the present invention, and FIG. FIG. 5 and FIG. 5 are schematic diagrams showing processing conditions using a conventional wire electrode. In the figure, (1) is a wire electrode, (2) is a workpiece,
(5) is a pulse power supply, (7) is a corner part. Note that the same reference numerals in the figures indicate the same or corresponding parts. Agent: Patent Attorney Masaru Sato 7th year, Corner Department 2nd [

Claims (4)

[Claims] (1) In an apparatus that feeds a wire electrode and applies a pulse voltage between the wire electrode and the workpiece to perform electrical discharge machining and cut the workpiece, the corner portion to be cut by the wire electrode is A wire electrode for a wire-cut electric discharge machine characterized by being formed with an irregular cross section that allows for sharp cutting. (2) A wire electrode for a wire-cut electrical discharge machine according to claim 1, wherein the cross section is rectangular. (3) A wire electrode for a wire-cut electric discharge machine according to claim 1, wherein the wire electrode has a triangular cross section. (4) A wire electrode for a wire-cut electric discharge machine according to claim 1, wherein the wire electrode has a flat cross section.