JP2000094137A - Tig welding torch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a tig welding torch to weld a narrow gap by making an electrode structural body in a flat cross section shape so that no welding wire passes between the electrodes and the width dimension can be made small. SOLUTION: A slender flat insulation plate 22 is held by two flat electrodes 23 from both right and left sides, a welding wire 14 is passed to the backward position deviated from the position of the insulation plate 22 between the electrodes to constitute an electrode structural body 24 made to a totally flat cross section shape. The cross section shape of the electrodes 23 is made to an elliptical, two-split elliptical or polygonal shape. The electrode structural body 24 is assembled with the center part of a torch main body through a collet 25 made of peripherally four-split structure comprising right and left collet bodies 25a and forward and rear spacer bodies 25b and projected downward through a gas cup.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a TIG welding torch used for narrow groove welding.

[0002]

2. Description of the Related Art A conventional TIG welding torch used for performing groove welding or the like by abutting members such as plate members is provided with a vertical electrode provided at a central portion of a torch body 1 as shown in FIG. At the lower end of the insertion hole 2, the upper end of a cylindrical collet body 4 having a tapered portion 3 at the lower end is screwed in. The collet body 4 has a slit 5 in a lower required area and a lower end. Collet body 4
Collet 6 having a tapered surface engaged with the inner surface of tapered portion 3
And a tungsten electrode 7 is vertically inserted into and held by the collet 6, and a lower end face of the collet 6 is located at an upper position of the collet 6 located in the electrode insertion hole 2 of the torch body 1. The torch cap 8 is screwed and arranged so as to abut on the upper end face, and the lower end of the collet 6 is pressed against the inner surface of the tapered portion 3 of the collet body 4 by tightening the torch cap 8 so that the electrode 7 is fixed. Further, an outer body 9 is integrally provided on the outer periphery of the lower part of the collet body 4, a gas lens 10 is attached to a lower end opening of the outer body 9, and the collet body 4 and the outer body are provided below the torch body 1. The gas cup 11 is attached to the outer periphery of the outer body 9 via a seal packing 11 a by screwing it around the outer body 9 so as to surround the outer cylinder 9. The Dogasu 13, collet body 4
The welding wire 14 is melted by the heat of the arc generated at the tip of the electrode 7 while being guided from the inside to the inside of the outer shell 9 and discharged from the tip (lower end) of the gas cup 11 through the gas lens 10, thereby forming a groove or the like. Welding is performed.

In recent years, a TIG welding torch using a multi-electrode system has been developed so that high-speed welding can be performed while allowing a large current to flow. In this case, since a plurality of electrodes cannot be fixed and held by using the collet 6 as shown in FIG. 3, for example, as shown in FIGS. The TIG welding torch 20 employs the collet 15 of FIG. That is, a collet 15 having a configuration in which two arc-shaped collet bodies 16 are combined in a cylindrical shape and a tapered surface 17 is formed on the outer periphery of a lower end portion is formed into an arc-shaped flat cross section.
An electrode structure 21 having an elongated flat insulating plate 19 interposed between the electrodes 18 and a welding wire 14 passing through the center of the insulating plate 19 is assembled so as to be inserted into the inner space of the collet 15. It is designed to be supported by the torch body. Reference numeral 4a denotes an insulator interposed between the divided portions of the collet body 4. 4 (a) (b) (c)
In FIG. 3, the same parts as those in FIG. 3 are denoted by the same reference numerals.

[0004]

However, FIG.
(B) In the case of the TIG welding torch 20 shown in (b) and (c), the electrode structure 21 protruding from the lower end of the gas cup 11
By setting the length to be long, narrow groove welding of a thick plate can be performed.
Since the two electrodes 18 have an arc-shaped flat cross section, there is a limit in reducing the width W of the electrode structure 21 (about 12).
mm), even if narrow groove welding is performed, there is a limit to the applicable groove width.

Accordingly, an object of the present invention is to provide a TIG welding torch capable of performing narrower groove welding.

[0006]

In order to solve the above-mentioned problems, the present invention provides an electrode structure in which an elongated flat insulating plate is sandwiched between two left and right electrodes by two electrodes. In a TIG welding torch which is supported by a torch main body via a collet held from a circumferential direction, a welding wire is inserted into a rear portion of the insulating plate, which departs from a position between the electrodes, and a longitudinal length of each of the electrodes is provided. A cross section perpendicular to the direction, a flat oval shape in the left-right direction, a shape obtained by dividing the oval shape into two in the left-right direction, or a flat polygonal shape in the left-right direction, and a configuration in which the electrode structure has a flat cross-sectional shape. I do.

Since the electrode structure has a flat cross-sectional shape so that the welding wire does not pass between the electrodes, the width can be reduced, so that it can be applied to welding with a narrower groove.

An electrode assembly groove is provided on both left and right side surfaces of the insulating plate so as to extend in the longitudinal direction, and an electrode is fitted into the electrode assembly groove. Can be further stabilized.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIGS. 1 (a) and 1 (b), an electrode mounting groove 22a having a required shape is provided along the longitudinal direction on both left and right side surfaces of an elongated flat insulating plate 22, and these electrode mounting grooves are provided. An electrode 23 having a cross section perpendicular to the longitudinal direction oblong in the left-right direction is fitted into each of the electrodes 22a.
The insulating plate 22 is sandwiched between the two electrodes 23 and the insulating plate 2
An electrode structure 24 having a flat cross-sectional shape is formed so that the welding wire 14 passes through the rear position deviated from the position between the two electrodes. In the present embodiment, the insulating plate 22 is divided into front and rear portions at a position where the welding wire 14 is passed for convenience of manufacture.

The above-structured electrode structure 24 is held by a collet 25 having a divided structure. The collet 25 has a circumferential four-segment structure including left and right collet bodies 25a made of an insulator and front and rear spacer bodies 25b made of an insulator interposed between the ends of the left and right collet bodies 25a. A tapered surface 25c for engaging the inner surface of the tapered portion 3 of the collet body 4 is formed on the outer periphery of the lower end, and the collet body 4 is connected to the lower end of the electrode insertion hole 2 of the torch main body 1 shown in FIG. The electrode structure 24 is screwed into the portion to protrude from the gas cup 11 by a required length.

In the TIG welding torch of the present invention, since the electrode structure 24 has a flat cross section so that the welding wire 14 does not pass between the electrodes 23, the width dimension W 'is shown in FIG. It can be reasonably smaller than W. Therefore, the present invention can be applied to welding of a narrow groove having a smaller width.

Next, FIG. 2 (a) (b) (c) (d)
(E), (f), (g), and (h) show other embodiments of the present invention, and show other examples of the cross-sectional shape of the electrode 23 of the electrode structure 24 in the above embodiment. is there.
That is, FIG. 2A shows a modified example of the elliptical electrode 23 shown in FIG. 1B, which has a flat elliptical shape in the left-right direction, and FIG. FIG. 2 shows a case where the elliptical electrode 23 shown is divided into two parts in the left direction.
(C) shows a shape obtained by dividing the elliptical electrode 23 shown in FIG. 2 (A) into two in the left-right direction, and FIG. FIG.
FIG. 2E shows a case where the electrode 23 has a flat trapezoidal shape in the left-right direction, FIG. 2F shows a case where the electrode 23 has a flat pentagonal shape in the left-right direction, and FIG. 2 shows a case where the electrode 23 has a flat hexagonal shape in the left-right direction, and FIG. 2 (h) shows a case where the electrode 23 has a flat rectangular shape in the left-right direction.

FIG. 2 (a) (b) (c) (d) (e)
(F), (g) and (h) can provide the same operational effects as those of the above-described embodiment, and the directivity of the arc can be obtained by selecting the shape of these electrodes 23. Can also be managed.

In the above embodiment, the electrode structure 2
4 shows a case where the electrode 23 is fitted into the electrode mounting groove 22a of the insulating plate 22 in order to further stabilize the assembly structure, but the electrode structure 24 is formed by a collet 25 of a corresponding shape. Since it is held from the direction, the above-mentioned electrode assembling groove 22a may be unnecessary, and in the embodiment,
Although the insulating plate 22 is divided at the position where the welding wire 14 is passed, the insulating plate 22 may be integrally formed, and it is needless to say that various changes can be made without departing from the gist of the present invention.

[0016]

As described above, according to the TIG welding torch of the present invention, an electrode structure in which an elongated flat insulating plate is sandwiched from both left and right sides by two electrodes is formed around the electrode structure. In a TIG welding torch which is supported by a torch body via a collet which is held from a direction, a welding wire is inserted through a rear portion of the insulating plate, which deviates from a position between the electrodes, and a longitudinal direction of each of the electrodes. The right-angled cross section is a flat oval shape in the left-right direction, a shape obtained by dividing the oval shape into two in the left-right direction, or a polygonal shape flat in the left-right direction, so that the electrode structure has a flat cross-sectional shape. Therefore, the width dimension of the electrode structure can be reduced,
Welding of a narrower groove than before becomes possible, and an electrode mounting groove is provided along the longitudinal direction on both left and right side surfaces of the insulating plate, and an electrode is fitted into the electrode mounting groove. Thereby, excellent effects such as stabilizing the assembly structure of the electrode structure can be exhibited.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a TIG welding torch of the present invention, in which (a) is a cut side view showing a structure of a portion holding an electrode structure, and (b) is a cut plan view of (a). It is.

FIG. 2 shows another embodiment of the present invention.
(B), (c), (d), (e), (f), (g), and (h) are cross-sectional views of electrode structures employing electrodes having different shapes.

FIG. 3 is a schematic view showing an example of a TIG welding torch.

FIG. 4 shows another example of a TIG welding torch.
(A) is an external view of a gas cup portion, (B) is a cut side view of a collet portion, and (C) is a cut plan view of (B).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Torch main body 14 Welding wire 22 Insulating plate 22a Electrode assembling groove 23 Electrode

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Kiyofumi Ishikawa 1 Shin-Nakahara-cho, Isogo-ku, Yokohama-shi, Kanagawa Ishikawajima-Harima Heavy Industries, Ltd. F-term (reference) 4E001 AA03 BB07 DB01 DF06 LF02 LH05 MD02 MD08 QA04

Claims (2)

[Claims] An electrode structure comprising an elongated flat insulating plate sandwiched between left and right sides by two electrodes is supported by a torch body via a collet which holds the electrode structure in a circumferential direction. In a TIG welding torch, a welding wire is inserted through a rear portion of the insulating plate, which is separated from the inter-electrode position, and a cross section of each electrode at right angles in the longitudinal direction is formed into a flat oval shape in the left-right direction. A TIG welding torch characterized in that the electrode structure has a flat cross-sectional shape as a shape obtained by dividing a circular shape into two in the left-right direction or a polygonal shape flat in the left-right direction. 2. The TIG welding torch according to claim 1, wherein an electrode assembling groove is provided on both left and right side surfaces of the insulating plate along the longitudinal direction, and the electrode is fitted into the electrode assembling groove.