JPH09122950A - Composite welding head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correctly achieve a laser beam welding and a TIG welding to the same part. SOLUTION: The TIG welding is achieved by applying the voltage between a tungsten electrode 111 provided on an electrode holder 110 and a base metal 50, and feeding the inert gas in the condition in which the arc is generated. Lenses 141-145 of a condensing lens optical system 140 are fitted to the outer circumferential surface of the electrode holder 110, and the laser beam welding is achieved by condensing the incident laser beam L which is guided by a laser beam guide optical system 130 on the surface of the base metal 50. Thus, the TIG welding and the laser beam welding can be achieved while being a correctly aligned to the same part to obtain the excellent welding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite welding head, and one welding head can simultaneously perform laser welding and TIG welding on the same portion of a workpiece.
Moreover, it is devised so that the welding can be easily performed in a state where the welding points of both weldings are exactly the same.

[0002]

2. Description of the Related Art Since laser light has a very high directivity and a large energy, it is used for precise welding, cutting, drilling, surface modification treatment, etc. by focusing on a small spot. . In this case, pulse wave laser light (PW) or continuous wave laser light (CW) is used according to the difference in the material of the work and the processing method. In general, pulse wave laser light has a short duration, so it is suitable for drilling small holes and spot welding without affecting the surroundings. Suitable for processing such as welding.

A YAG laser oscillator, which is a type of solid-state laser oscillator, is a YAG (yttrium, aluminum, garnet) doped with Nd as a laser single crystal.
A crystal is used, and a laser beam having a wavelength of 1.064 μm is output as a pulse wave laser beam or a continuous wave laser beam. Since the YAG laser light is an infrared laser light having a wavelength of 1.064 μm, it can be transmitted by an optical fiber. As a result, in the welding device using the YAG laser oscillator, the laser light can be routed by the optical fiber, and the degree of freedom in design and arrangement is great.

When laser welding is performed by such a laser welding apparatus, it is possible to perform welding with a deep penetration depth in a narrow welding range. This is because the laser light has a very strong condensing property, and the laser light functions as a powerful concentrated heat source having an extremely high energy density.

On the other hand, as a conventional welding method, TIG welding (inert gas shielded tun) is used.
gsten arc welding) is known. TIG
Welding is a method in which an arc is generated between a tungsten electrode and a base material in an inert gas atmosphere such as argon or helium to perform welding. In such TIG welding, since the arc spreads over a wide range, it is possible to perform welding over a wide welding range although the penetration depth is shallow.

In recent years, studies have been conducted to simultaneously perform laser welding and TIG welding on the same welded portion so that a deep penetration depth can be obtained over a wide welding range.

As an apparatus studied so that laser welding and TIG welding can be performed simultaneously, there is an apparatus shown in FIGS. 2 and 3.

In the apparatus shown in FIG. 2, the TIG welding head 1 is used.
The tip portion of the tungsten electrode 2 is bent at a right angle, and the TIG welding head 1 is arranged horizontally with respect to the surface of the base material 3. Then, an arc 4 is generated between the tip of the bent tungsten electrode 2 and the base material 3. On the other hand, the condenser lens system 5 (only one lens is shown in the figure for simplification, but a plurality of lenses are actually combined) is used to condense the laser light 6 and irradiate the base material 3 obliquely. ing. The relative phase relationship between the TIG welding head 1 and the condenser lens system 5 is maintained so that the welding point of the arc 4 and the irradiation point of the laser light 6 coincide with each other.

In the device shown in FIG. 3, the tungsten electrode 2
The TIG welding head 1 in which a is straightened is arranged obliquely with respect to the surface of the base material 3 and an arc 4 is generated between the tungsten electrode 2 a and the base material 3. On the other hand, the base material 3 is obliquely irradiated with the laser light 6 condensed by the condenser lens system 5.
Then, the TIG welding head 1 is set so that the welding point by the arc 4 and the irradiation point by the laser beam 6 coincide with each other.
The relative positional relationship between the condenser lens system 5 and the condenser lens system 5 is maintained.

[0010]

By the way, in the apparatus shown in FIG. 2, since the tip of the tungsten electrode 2 is bent, the shape of the arc 4 may be unstable and stable welding may not be possible.

2 and 3, the TIG welding head 1 is designed so that the welding point by the arc 4 and the irradiation point of the laser beam 6 coincide with each other even if the welding position and the welding posture are changed. The relative positional relationship between the condenser lens system 5 and the condenser lens system 5 must be maintained, and troublesome positional adjustment must be frequently performed during use, resulting in poor usability. Further, since the laser light 6 is obliquely incident on the base material 3, the shape of the molten pool is not symmetrical and the welded shape may be deteriorated. Further, depending on the welding position and the welding posture, if an attempt is made to establish a relative positional relationship such that the two points coincide with each other, it may interfere with surrounding members and devices, and a good relative positional relationship may not be obtained. In such a case, good welding cannot be performed.

In view of the above-mentioned conventional technique, the present invention provides a composite welding head in which the welding points of TIG welding and laser welding are always the same and which has good operability.

[0013]

The structure of the present invention for solving the above-mentioned problems is to provide a cylindrical electrode holder for enclosing and holding the tungsten electrode in a state where the tungsten electrode projects from the tip, and to guide laser light. A laser light guide optical system for injecting the lever laser light from the base end side of the electrode holder toward the tip end side, and a hole formed in the central portion to be fitted on the outer peripheral surface of the electrode holder and the shaft of the electrode holder. Condensing lens optics, which is composed of a plurality of ring-shaped lenses arranged in line with each other and condenses laser light input from the base end side of the electrode holder to a point ahead of the tip of the tungsten electrode. It is characterized by consisting of Further, in the present invention, the electrode holder has a reflective film formed by gold coating on its surface.

In the present invention, since the condenser lens optical system is fitted to the electrode holder, the head structure is compact and does not interfere with peripheral members, and the points of laser welding and TIG welding are always the same. Good welding is coming.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to FIG. As shown in FIG. 1, in a composite welding head 100 according to the present embodiment, a cylindrical electrode holder 110 contains and holds a tungsten electrode 111, and the tungsten electrode 111 is a tip portion (lower end portion) of the electrode holder 110. ). Further, a reflection film 110a formed by gold coating is applied to the outer peripheral surface of the electrode holder 110.

The power supply unit 112 includes a tungsten electrode 111.
A voltage is applied between the base material 50 and the base material 50. As a result, an arc 113 is generated between the tungsten electrode 111 and the base material 50. Further, the inert gas source 114 is the electrode holder 110.
An inert gas is supplied to the base end of the. The supplied inert gas flows from the base end portion (upper end portion) to the tip portion inside the electrode holder 110, and is jetted from the tip portion to wrap the arc 113 and the welded portion of the base material 50.

The YAG laser device 120 has a laser beam L
Occurs. The laser light guide optical system 130 includes an optical fiber 131, a total reflection mirror 132 fitted in the electrode holder 110, and an optical fiber holder 133. The total reflection mirror 132 is provided on the electrode holder 110 in an oblique state. And the optical fiber 131
Is the laser light L generated by the YAG laser device 120.
Are guided to the vicinity of the electrode holder 110. Further, the total reflection mirror 132 reflects the laser light L emitted from the optical fiber 131, and causes the reflected laser light L to enter from the base end side of the electrode holder 110 toward the front end side.

The condensing lens optical system 140 is composed of a plurality of lenses 141 to 145 and one protective glass 146. The lenses 141 to 145 each have a hole formed in the center thereof, are fitted on the outer peripheral surface of the electrode holder 110, and are arranged side by side in the axial direction of the electrode holder 110. Further, the protective glass 146 is used for the lenses 141 to 145.
It is fitted on the electrode holder 110 at a position closer to the tip end than the electrode holder 110.

Lenses 141 to 151 of the condenser lens optical system 140
The laser beam L reflected by the total reflection mirror 132 and incident on the light source 145 is focused on a point ahead of the tungsten electrode 111. Therefore, the laser light L is focused on the surface portion of the base material 50 and contributes to laser welding.

The composite welding head 1 having such a structure
In 00, TIG welding by the arc 113 and laser welding by the laser beam L can be simultaneously performed on the same portion of the base material 50, and welding with a deep penetration depth can be favorably performed over a wide welding range. it can. in this case,
Since the laser light L is directly incident on the surface of the base material 50 and the arc 113 is formed on the target, the weld pool is symmetrical, and the welding quality and welding shape are good.

In addition, the composite welding head 100 includes a TIG welding system (electrode holder 110, tungsten electrode 11).
1) and the laser welding system (the condensing lens optical system 140 and the laser light guide optical system 130) are integrated, so that even if the welding position or welding position is changed, no special operation is required. The TIG and laser welds always match. Therefore, operability is good and good welding can be performed. Further, since it has an integral structure, it is compact and does not interfere with surrounding members.

Since the outer peripheral surface of the electrode holder 110 is coated with the gold coat reflection film 110a, the laser light L is not absorbed by the electrode holder 110 and the electrode holder 110 does not generate heat by the laser light L. .

Further, the protective glass 111 is made up of the lenses 141 to 141.
Since it is located closer to the tip side than 145, dirt due to welding may adhere to the protective glass 111, but does not adhere to the lenses 141 to 145.
145 can be prevented from becoming dirty. When the protective glass 146 becomes dirty, the protective glass 146 is cleaned or the protective glass 146 is replaced.

In the example of FIG. 1, the laser device is Y
Although an AG laser device is used, other types of laser devices may be used. When another type of laser device is used, a reflecting mirror or the like is used instead of the optical fiber 131 to guide the laser light.

[0025]

According to the present invention as specifically described in connection with the above embodiments, the condenser lens optical system is integrally provided on the outer periphery of the electrode holder provided with the tungsten electrode, and the laser light guide optical system is used. Since the guided laser light is focused on a point ahead of the tungsten electrode by the condenser lens optical system, laser welding and TIG welding can be performed simultaneously on the same portion with high precision and operability. In addition, it is compact as a whole and there is no interference with surrounding members.

Further, since the surface of the electrode holder is coated with the reflecting film by gold coating, the electrode holder does not generate heat by the laser beam.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a composite welding head according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing a conventional technique.

FIG. 3 is a configuration diagram showing a conventional technique.

[Explanation of symbols]

 1 TIG welding head 2, 2a Tungsten electrode 3 Base material 4 Arc 5 Condenser lens system 6 Laser light 50 Base material 100 Composite welding head 110 Electrode holder 110a Reflective film 111 Tungsten electrode 112 Power supply section 113 Arc 114 Inert gas source 120 YAG Laser device 130 Laser light guide optical system 131 Optical fiber 132 Total reflection mirror 133 Optical fiber holder 140 Condensing lens optical system 141 to 145 Lens 146 Protective glass

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Akabane 1-1-1, Wadazaki-cho, Hyogo-ku, Kobe-shi, Hyogo Mitsubishi Heavy Industries Ltd. Kobe Shipyard

Claims (2)

[Claims] 1. A cylindrical electrode holder that encloses and holds the tungsten electrode in a state where the tungsten electrode projects from the tip, and a laser beam that guides the laser beam from the base end side to the tip side of the electrode holder. A laser light guide optical system which is incident on the optical axis, and a plurality of ring-shaped lenses each having a hole formed in the central portion, fitted on the outer peripheral surface of the electrode holder, and arranged along the axial direction of the electrode holder. And a condenser lens optical system for condensing the laser light input from the base end side of the electrode holder at a point ahead of the tip of the tungsten electrode. 2. The composite welding head according to claim 1, wherein the electrode holder has a reflective film formed by gold coating on its surface.