JPS60106688A - Laser working device - Google Patents

Abstract

PURPOSE:To unite a molten pool which is formed by combination use of laser welding and inert gas arc welding with a welding device which makes combination use of both welding by providing an aperture for irradiating laser light to the electrode part of arc welding. CONSTITUTION:Electrodes 19 for TIG welding are formed into a cylindrical shape and a hole 22 for passage of laser light is provided in the central part thereof. Four pairs of eight electrodes such as (a), (b) are built in the electrode 19 via a cylindrical insulator 23 and a gap for supplying an inert gas 11 is provided on the outside circumference thereof, by which a nozzle 20 is assembled. Each two electrodes 19 making a pair are respectively conductably connected. Welding is accomplished by firing the electrodes 19 of the set (a) by using high frequency and irradiating laser light 2 through the hole 22. The gas 11 is supplied through the hole 22 as well in addition to the supply through the nozzle 20. The arc generated before and behind the laser light increases the absorption rate of the laser light right under the part to be irradiated with the laser, thereby increasing the depth of penetration.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a laser processing device, and more particularly to a welding device that can be used by combining an ignited arc with a condensing portion of a laser beam.

[Background of the invention]

FIG. 1 shows an outline of a welding device that uses both laser welding and inert gas tungsten arc welding (abbreviated as TIG welding). FIG. 2 is an enlarged view of the vicinity of the weld. Welding is performed by applying electricity from a power source 6 between a TIG welding torch 7 fixed by an arm 8 and a material to be welded 9, and using a tungsten electrode 1.
arc 13 is generated to form a molten pool 14. The welding portion 15 is welded by condensing and irradiating the laser beam 2 onto this. At this time, welding is performed while shielding while supplying inert gases 11 and 12 from the laser nozzle 5 and TIG welding torch 7.

In this method, as shown in FIG. 2, the distance Q between the heated part A by TIG welding and the irradiated part B of the laser beam 2 needs to be several tens of mm from the dimensions of the laser welding nozzle 5 and the torch 7. The same molten pool is not formed and the effect of using the rewelding method in combination is small. Therefore.

Efforts have been made to increase the amount of heat input during TIG welding and to make the molten pool 14 thicker. That is, (1) increase the welding current.

(2) Slow down the welding current.

(3) Lengthen and tilt the tungsten electrode to bring it closer.

In these methods, the cross section of the welded part is inevitably as shown in FIG. 3, and problems such as TIG welding, welding distortion, welding deformation, and material embrittlement arise. Excessive welding current has the disadvantage of blowing up the molten metal and worsening the appearance of the weld bead. When supplying the filler metal, it is necessary to supply it by the feeding device 17 as shown in Fig. 4, and since the distance Q between the two melting centers cannot be large, it is nearly horizontal as shown in Fig. 4. The work efficiency is poor because the material must be fed from both directions. If the distance Q is long, it becomes easier to form a semi-molten layer 18, and since the laser beam irradiated part B is welded at such a low temperature that it solidifies, the absorption rate of the laser beam decreases and the weld penetration depth decreases as shown in Fig. 5. This results in shallow welding.

Furthermore, with - number of tungsten electrodes, the welding direction is only one direction, and welding in multiple directions cannot be performed.

[Purpose of the invention]

An object of the present invention is to provide a laser processing machine in which a molten pool formed by a combination of laser welding and TIG welding is integrated, and a deep penetration depth can be obtained by using a combination of surface welding.

[Summary of the invention]

The main point of the present invention is to irradiate the inside of the arc generated by the TIG welding electrode with a laser beam, make the arc column cylindrical,
The purpose is to irradiate the center with laser light. In other words, multiple TIG welding electrodes are used to form a cylindrical shape, a laser is passed through the center of the electrode, the laser beam irradiated area is heated to a molten state, and the absorption rate of the laser beam is increased, making it possible to perform deep welding. This is what I did.

[Embodiments of the invention]

FIG. 6 shows a sectional view of a main part according to the present invention. FIG. 7 is a schematic diagram of the head tip viewed from the damaged welding material side. T.I.G.
Welding electrodes 19 are assembled in 4 pairs of 8 electrodes with cylindrical insulators 23 in between. Its outer periphery is filled with inert gas (Ar, H
e) A nozzle 20 is assembled with a gap for supplying 11. The electrodes were wired so that two pairs (four pairs of a, b, etc.) of each electrode could be separately energized. Welding was performed by igniting the electrodes 19 of group a of TIG welding using high frequency and irradiating the laser beam 2 through the beam passage hole 22. At this time, Ar gas 12 is supplied from the welding nozzle 20 and Ar gas 11 is also supplied from the beam passage hole 22 to prevent oxidation from oxygen in the atmosphere.

It was also effective for cooling purposes. The insulating ring 21 insulates the nozzle 20 and the electrode 19 and seals the nozzle 20 to prevent Ar gas from leaking. The arc generated before and after the laser beam increased the laser beam absorption rate directly under the laser beam irradiation area, resulting in deeper penetration depth. According to the method shown in Fig. 8, the bead width is narrower than that shown in Fig. 5, there is less heat influence, and the weld bead embankment with the same penetration depth can be achieved even at more than twice the welding speed of the conventional method. A good welded joint with little rise was obtained.

In Figure 9, a cylindrical tungsten tip 27 is attached to the tip of the electrode, the nozzle 20 is made of ceramic to insulate it and increase body heat resistance, and a condensing lens 4 for laser light is mounted on the top of the welding head via the #8 edge. A lens holder 24 is incorporated. Welding was performed by supplying Ar gas 11 from the lens holder.

When the welding direction changes, the pair of electrodes is electrically switched from a to b in Fig. 7, but in Fig. 9
With the method shown in the figure, this operation was completely unnecessary and welding could be performed in any direction. In addition, the condensing lens of the laser beam is
Since it is integrated with the IG welding electrode, three-dimensional angle selection can be done by simply adjusting the laser beam, eliminating the need for complex adjustments such as the distance, angle, and direction between the laser beam and the TIG welding electrode.

By using a cylindrical electrode for TIG welding, the arc pressure was reduced, and even when the welding current was increased, the phenomenon of the weld metal popping off and being blown away was eliminated, and a welded part with good deep penetration was obtained.

In the figure, 1 is a laser oscillator, 4 is a condensing range, and 16 is a filler material.

〔Effect of the invention〕

According to the present invention, the molten pool formed by TIG welding and laser welding can be integrated, and deep penetration welding can be performed with high efficiency.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a welding device that uses a combination of conventional laser welding and TIG welding, Fig. 2 is a sectional view of the main parts of conventional welding, and Fig. 3
The figure is a cross-sectional view of a conventional weld zone, FIG. 4 is a schematic diagram of a conventional filler metal supply, FIG. 5 is a cross-sectional view of a weld zone with a conventional filler metal supply, and FIG. 6 is a main part according to the present invention. FIG. 7 is a schematic diagram of a main part according to the present invention, FIG. 8 is a cross-sectional view of a welding part according to the present invention, and FIG. 9 is a schematic cross-sectional view of a welding head according to the present invention. 2... Laser light, 6... TIG welding power source, 9...
Material to be welded, 13... Arc, 15... Welding part, 19
...Electrode, 1st mouth, 2nd bacteria, 3rd decoy, 4th day,! 5 Kuni No. 6 Figure b μ

Claims (1)

[Scope of Claims] (1) In a welding device that combines laser welding and inert gas arc welding, an opening for irradiating a workpiece with a laser beam is provided in the electrode portion of the inert gas arc welding, and A laser processing apparatus characterized in that the arc heat generated by energization and the molten pool formed by the laser beam irradiated through the aperture are integrated. 2. In claim 1, a welding head with a double structure is configured by the electrode that generates an arc and an outer cylinder that supplies a shielding gas for preventing oxidation, and the welding head is configured to have a double structure between the electrode section inside and the workpiece. 1. A laser processing device characterized in that the laser processing device is configured to perform welding by irradiating a laser beam onto the central portion of an arc generated in the process. 3. In claim 2, the plurality of electrodes are arranged symmetrically with respect to the irradiation part of the laser beam through a heat-resistant insulator, and the electrodes are arranged in pairs in the direction of welding progress. A laser processing apparatus characterized in that the welding is performed by applying current, igniting the laser beam together with the irradiation, and performing welding while changing the pair of electrodes to be energized in accordance with a change in the welding direction. 4. In claim 2, the electrode structure for generating the arc is annular, and when energized, a hollow annular arc is formed between the arc and the workpiece, and the laser beam is directed into the hollow part. A laser processing device that performs welding while irradiating. 5. In claim 2, a double-structured welding head consisting of the electrode part and the outer cylinder part, and an optical system for condensing the laser beam, are arranged closer to the workpiece than the electrode part. A laser processing apparatus characterized in that the laser beam is fixed to the upper part of the outer cylinder so as to be condensed, and the electrode part is supported inside the outer cylinder via an insulator to form an integrated structure.