JP2003311456A - Laser beam irradiating arc welding head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a welding head which needs no large sized structure, which shows less energy loss of a laser beam, and which has improved shielding performance of a welding head by a shielding gas. <P>SOLUTION: In the laser beam irradiating arc welding head, N pieces of semiconductor laser stacks LD3 are arranged around a nozzle 21 mounted on the tip end of a welding torch 15 and, by N pieces of condensing lens optical systems, laser beams are each converged near the intersection between a wire 14 fed from the welding torch and an aimed welding position on an object to be welded. In addition, the welding head is equipped with a head nozzle 36. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to laser irradiation of a laser irradiation arc welding apparatus for performing high-speed welding by irradiating a surface of an object to be welded at an arc generation portion or its peripheral portion of consumable electrode gas shielded arc welding. Regarding improvement of an arc welding head.

[0002]

2. Description of the Related Art Laser welding using a carbon dioxide gas laser, a YAG laser, a semiconductor laser, etc. is a heat source with a high energy density, so that high-speed welding exceeding 2 [m / min] to about 8 [m / min] is possible. It is possible. However, in this laser welding, when there is a gap in the joint portion in welding to a lap joint, a butt joint, etc., the beam spot of the laser irradiation portion is small, so both ends of the joint portion with the gap can be melted. You can't do welding. Therefore, in laser welding, it is necessary to make the joint part of the work piece have no gap,
The practical application range is very limited.

Solving the above problems of laser welding 1
As one method, a composite type laser irradiation arc welding apparatus that uses laser irradiation and consumable electrode gas shield arc welding together has been proposed. This welding method ensures high-speed weldability by the high-energy-density heat source formed by laser irradiation described above, and then melts the joint widely with the expansive heat source formed by the arc, and the wire to the gap portion. By filling, good high-speed welding can be performed even on a joint portion having a gap. Hereinafter, an example of this laser irradiation arc welding device will be described. In the following description, the case where the welding speed is 2 [m / min] or more is referred to as high speed welding.

FIG. 1 is a diagram showing a conventional laser irradiation arc welding apparatus. Hereinafter, description will be given with reference to FIG.
The laser light 2 output from the laser oscillator 1 of a YAG laser or a semiconductor laser is converged by the first lens 3 and output to the optical fiber 4. Then, the laser light 2 transmitted by the optical fiber 4 is bent 90 [degree] by the mirror 6 provided in the laser torch 5, and the laser light 2 that is reflected and spread becomes parallel light by the second lens 7, It is converged by the processing lens 8 so that a focus is generated on the surface of the object to be welded 9, and the object to be welded 9 is irradiated through the cover glass 10.

The welding power source device 11 is a wire feeding device 1.
The wire 14 is controlled by controlling the rotation of the wire feeding roll 13
Is fed through the welding torch 15 and the wire 14
The welding voltage and welding current for generating the arc 16 between the welding target 9 and the workpiece 9 are output. The position of irradiating the laser beam 2 may be a position where the arc 16 of the workpiece 9 is generated or a peripheral part thereof, and the arc 1 is set on the basis of the welding direction.
It may be located at the front, the rear, the right side, or the left side of the generating portion of 6.

[0006]

In the above-described laser irradiation arc welding apparatus of the prior art, since welding is performed using two torches, the laser torch 5 and the welding torch 15, the respective torches do not interfere with each other. In addition, it is necessary to provide one or both torches inclined with respect to the workpiece 9. As a result, laser torch 5 and welding torch 1
Since the welding head composed of 5 and 5 is enlarged and is usually attached to the tip of a manipulator of a welding robot (not shown), the welding direction is limited and the operability of the welding robot is deteriorated. Further, since the laser torch 5 precedes and the welding torch 15 follows and performs welding, it is necessary to operate the manipulator with the positions of the laser torch 5 and the welding torch 15 being fixed. For example, when the welding line bends about 90 [degrees], the welding torch 15 needs to be largely rotated, which complicates the teaching operation of the manipulator. Further, since the laser light 2 output from the laser oscillator 1 is collected and incident on the fiber 4 to transmit the laser light 2, the laser light 2 is transmitted to the fiber 4 when the laser light 2 is incident on the fiber 4. When the laser beam is emitted, energy loss of the laser beam 2 occurs.

When aluminum or aluminum alloy (hereinafter referred to as "aluminum") is welded as the object 9 to be welded, in order to perform a cleaning action for removing an oxide film existing on the surface of the aluminum, compared with welding of mild steel. , Need to shield a wide range. However, the conventional laser irradiation arc welding apparatus shown in FIG. 1 does not have a structure in which the shield gas can sufficiently shield the arc and the molten metal from the atmosphere. You can't shield. Therefore,
When welding aluminum as an object to be welded, because the shielding gas cannot sufficiently shield the arc and molten metal from the air, the molten metal entrains air and causes porosity defects such as blow holes. There was a problem that the quality of the.

[0008]

According to a first aspect of the present invention, an electric power is supplied between a wire 14 fed from a consumable electrode gas shielded arc welding torch 15 and a work 9 to form an arc 16. In the laser irradiation arc welding head, which generates and irradiates the laser beam 2 output from the semiconductor laser stacks LD1 to LDN composed of a plurality of semiconductor lasers to the generation portion of the arc 16 or its peripheral portion, the consumable electrode gas N (N is an integer of 1 or more) semiconductor laser stacks LD1 to LDN arranged around a nozzle 21 attached to the tip of the shield arc welding torch 15, and the above N
Each laser beam 2 output from each of the semiconductor laser stacks LD1 to LDN is condensed, and N laser condensing points are set near the welding target position where the wire feeding direction and the workpiece are intersected. A laser irradiation arc welding head having a condenser lens optical system.

According to a second aspect of the invention, the N semiconductor laser stacks LD1 to LDN are arranged such that the optical axes of the respective light emitting points are in the welding target position direction of the workpiece 9. The laser irradiation arc welding head according to claim 1, wherein LD1 to LDN are provided.

According to a third aspect of the present invention, the shield gas 2 which penetrates the free end side in the radial direction and is supplied to the nozzle 21 is provided.
The laser irradiation arc welding head according to claim 1 or 2, further comprising a nozzle 23 which is provided with a nozzle 23a to which the same shield gas 38 as that of No. 2 is supplied and which is further provided around the nozzle 21.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. 2 is a partial cross-sectional view of the laser irradiation arc welding head 37 of the present invention, and FIG. 3 is a plan view of the laser irradiation arc welding head 37 of the present invention. In FIG. 2, the welding torch 15 is arranged at the center of the laser irradiation arc welding head 37. A feed tip 18 is attached to the tip of a tip body 17 of the welding torch 15, and an orifice 19 made of an insulating material provided with a shield gas jet on the side surface is provided around the shield gas jet of the tip body 17 and made of an insulating material. The insulating bush 20 is arranged around the tip body 17, and the first nozzle 21 is connected to the power supply tip 18
Is surrounded by. The shield gas 22 supplied from a gas cylinder (not shown) passes through the shield gas jet port of the tip body 17, the shield gas jet port of the orifice 19, and is jetted from the tip of the first nozzle 21 to blow the molten pool from the air. Shield. The feeding chip 18 is the feeding chip 1
The wire 14 is guided by inserting the wire 14 into the wire insertion hole 8 and the power supplied from the welding power source device 11 is supplied through the chip body 17 to the power feeding tip 1
8 and the wire 14 is inscribed in the power feed tip 18 to supply power to the wire 14.

The orifice 19 protects the tip body 17 from the spatter scattered from the molten pool. When the orifice 19 is not provided, the shield gas 22 flows from the shield gas ejection port of the tip body 17 to the first nozzle 2
Although the flow of the shield gas 22 is not stable because it is jetted to the inner surface of No. 1, when the orifice 19 is provided, the shield gas 22 jetted from the shield gas jet port of the tip body 17 is further shielded at the orifice 19. By passing through the gas ejection port, the flow velocity becomes uniform and the flow becomes stable.

A second nozzle 23 is provided around the first nozzle 21, and the same shield gas 38 as the shield gas 22 supplied to the first nozzle 21 is supplied. A jet port 23a penetrating in the radial direction is provided on the free end side of the second nozzle 23, and the shield gas 38 is jetted from the jet port 23a and the tip of the second nozzle 23. The shield gas 38 supplied to the second nozzle 23 prevents the purity of the shield gas 22 ejected from the first nozzle 21 from being lowered, and the vicinity of the tip of the power supply tip 18 of the welding torch 15 from the outside atmosphere. It shields and further prevents the shield gas 22 ejected from the first nozzle 21 from being disturbed by the cross air 35 described later.

Next, as shown in FIG. 3, semiconductor laser stacks LD1 to LD8 each having a structure in which bars, in which semiconductor lasers are arranged, are vertically stacked around the second nozzle 23 attached to the tip of the welding torch. Are arranged radially. Cold water is supplied to the upper portions of the semiconductor laser stacks LD1 to LD8 from a chiller 24 which is a chiller device shown in FIG.
A cold water inlet 25 and a cold water outlet 26 for returning to No. 4 are provided respectively. In addition, the semiconductor laser stack LD1
Through LD8, the semiconductor laser power supply device 27 shown in FIG.
Electrodes 28 for supplying electric power from each are provided. In FIG. 2, the semiconductor laser stack LD
About 7 Chiller 24 and semiconductor laser power supply 27
The connection with the chiller of the semiconductor laser stack LD3 and the semiconductor laser power supply device is omitted.

As shown in FIG. 2, a semiconductor laser stack
A condenser lens optical system described below is arranged below the LD1 to LD8. First, semiconductor laser stacks LD1 to L
The laser light 2 output from D8 is converted into parallel rays by the microlens 29, the direction of the parallel rays is changed by the prism lens 30, and the cylindrical lens 3
The laser beam 2 passes through the protection window 33 and is fed from the welding torch 15 by the focus lens 32 and the focus lens 32 so that the laser beam 2 is focused in the vicinity where the wire 14 crossing the welding target position of the workpiece 9 is intersected. Be focused.
The protection window 33 is provided to prevent fume and spatter from adhering to the condenser lens optical system during welding.

The cross air 35 ejected from the cross air ejection port 34 is ejected in parallel with the surface of the protection window 33, and the cross air ejection port of the head nozzle 36 is ejected.
Emitted from 36a. As a result, the metal vapor generated by the arc welding is prevented from adhering to and contaminating the condenser lens optical system. Further, even when a droplet and a part of the molten pool scatter as spatter during welding, the spatter is prevented from adhering to and contaminating the condenser lens optical system.

In FIG. 3, eight semiconductor laser stacks LD1 to LD8 are shown, but eight semiconductor laser stacks are provided.
It is not limited to individual pieces. By changing the number of the semiconductor laser stacks, the condensing characteristic of the laser light 2 can be changed. This can stabilize the arc welding.

The laser irradiation arc welding head 37 of the present invention
Since it has the above-mentioned structure, it does not become large-sized like the welding head of the prior art. Therefore, when it is attached to the tip of the manipulator of the welding robot, the welding direction is not limited, and Operability does not deteriorate. Further, the teaching work of the manipulator does not become complicated.

Further, unlike the welding head of the prior art, since the laser beam 2 output from the laser oscillator 1 is not focused and incident on the fiber 4 to transmit the laser beam 2, the energy loss of the laser beam 2 is caused. Less is.

The laser irradiation arc welding head 37 of the present invention
Since the head nozzle 36 is provided, the shielding property of the welding head 37 by the shield gas is improved so that the arc 16 and the molten metal can be shielded from the atmosphere even in the case of welding at a high welding speed. Therefore, the welding quality is improved. Further, since the shield gas 22 can sufficiently shield the molten pool from the atmosphere even with respect to the object 9 to be welded, such as aluminum, which is required to have a high shielding property, the molten metal does not involve the atmosphere. There is no problem of degrading the quality of welding such as generation of pore defects such as blowholes.

The semiconductor laser stack LD1 shown in FIG.
LD8 are arranged in parallel with the wire feed axis of the welding torch 15. Instead of this, semiconductor laser stacks LD1 to L
The semiconductor laser stack LD1 is arranged so that the optical axes of the respective light emitting points of D8 are directed toward the welding target position of the workpiece 9.
By disposing LD8 to LD8, the prism 30 can be omitted.

Although the embodiment in which the present invention is applied to the consumable electrode gas shield arc welding torch has been described, the present invention can also be applied to the TIG welding torch.

[0023]

Since the present invention is constructed as described above, it has the following effects. The laser irradiation arc welding head of the present invention has N semiconductor laser stacks arranged around a nozzle attached to the tip of the welding torch, and is fed from the welding torch by N focusing lens optical systems. Each laser beam is focused in the vicinity where the wire intersects the welding target position of the workpiece.
As a result, since the welding head of the related art does not become large in size, when mounted on the tip of the manipulator of the welding robot, the welding direction is not restricted, and the operability of the welding robot may deteriorate. Absent. Further, the teaching work of the manipulator does not become complicated.

Further, unlike the welding head of the prior art, since the laser light output from the laser oscillator is not focused and incident on the fiber to transmit the laser light, the energy loss of the laser light is small.

Further, since the laser irradiation arc welding head is provided with the head nozzle, the shielding property of the welding head by the shield gas is improved, and the arc and the molten metal can be separated even in the case of welding at a high welding speed. Since it becomes possible to shield from the atmosphere, the welding quality is improved. In addition, since the shielding gas can sufficiently shield the arc and the molten metal from the atmosphere even for an object to be welded, such as aluminum, which is required to have a high shielding property, the molten metal may be involved in the atmosphere. In addition, there is no problem of degrading the quality of welding such as generation of pore defects such as blowholes.

[Brief description of drawings]

FIG. 1 is a diagram showing a prior art laser irradiation arc welding apparatus.

FIG. 2 is a partial cross-sectional view of the laser irradiation arc welding head of the present invention.

FIG. 3 is a plan view of a laser irradiation arc welding head of the present invention.

[Explanation of symbols]

1 Laser oscillator 2 laser light 3 First lens 4 optical fiber 5 laser torch 6 mirror 7 Second lens 8 Processing lens 9 Workpiece to be welded 10 cover glass 11 Welding power supply 12 wire feeder 13 Wire feeding roll 14 wires 15 welding torch 16 arc 17 chip body 18 Power supply chip 19 Orifice 20 insulating bush 21 first nozzle 22 Shield gas 23 Second nozzle 24 chillers 25 Cold water entrance 26 Cold water outlet 27 Semiconductor laser power supply device 28 electrodes 29 micro lens 30 prism lens 31 Cylindrical lens 32 focus lens 33 Protection window 34 Cross Air Jet 35 Cross Air 36 head nozzle 36a Cross air outlet 37 Laser irradiation arc welding head 38 Shield gas ejection port of the second nozzle 23 LD1 to LD8 Laser diode stack

Continued front page    (72) Inventor Tetsuya Anfuku             2-11-1, Tagawa, Yodogawa-ku, Osaka-shi, Osaka             Daihen Co., Ltd. F-term (reference) 4E001 AA03 BB12 DF09 LH02 MB10                       NA01                 4E068 AA01 BC01 CA01 CA08 CD02                       CD15 CH08 CJ01

Claims (3)

[Claims] 1. A consumable electrode gas shielded arc welding torch supplies electric power between a wire and an object to be welded to generate an arc, which is output from a semiconductor laser stack composed of a plurality of semiconductor lasers. In a laser irradiation arc welding head that respectively irradiates the laser generation part or its peripheral part with the laser generation part, N (N) arranged around the nozzle attached to the tip of the consumable electrode gas shielded arc welding torch. Is an integer greater than or equal to 1) and the respective laser beams output from the N semiconductor laser stacks are condensed, and the vicinity of the welding target position where the wire feeding direction and the workpiece are intersected Laser irradiation arc welding head equipped with N condensing lens optics with the laser condensing point as. 2. The laser according to claim 1, wherein the N semiconductor laser stacks are arranged such that the optical axes of the light emitting points of the N semiconductor laser stacks are in the welding target position direction of the workpiece. Irradiation arc welding head. 3. A nozzle further comprising a nozzle, which is formed on the free end side in the radial direction, and which is provided around the nozzle to which the same shield gas as the shield gas supplied to the nozzle is supplied. The laser irradiation arc welding head according to 1 or 2.