JP2001001172A - Method for laser beam welding and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for laser beam welding capable of simplifying preliminary preparation for welding and having little deformation owing to welding. SOLUTION: A carriage 11 equipped with a torch 14 to emit laser beam is made to travel on overlapped sheets (steel sheets 1, 2) along positions to be welded subjected to laser beam welding, and the overlapped sheets are made closely adhered by own gravity of this carriage 11 and then laser beam welding at the position to be welded is executed. By means of the method mentioned above, close adherance of the overlapped sheets is obtained by own gravity of the carriage 11; thus defective welding and deformation of the overlapped sheets are prevented, there comes no need of conventional tack welding, and then preliminary preparation for welding is simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser welding method used for welding lapping materials and an apparatus therefor.

[0002]

2. Description of the Related Art Conventionally, when welding lapping materials, slot welding or slit welding is performed using coated manual welding (SMAW) or semi-automatic welding (GMAW). The welding of the overlapped material is carried out, for example, in a ship or an automatic warehouse, for example, for manufacturing a double floor on which a transport vehicle moves.

FIG. 4 shows a method of welding a lap material by covering manual welding (SMAW) or semi-automatic welding (GMAW).
It will be described in detail based on. In FIG. 4, reference numerals 1 and 2 denote overlapping members (steel plates to be overlapped and welded). 1. First, before welding, as shown in FIG. 4A, holes 3 (or slits 4) are formed in the steel sheet 1 by gas cutting (plasma or laser cutting may be performed).

[0004] 2. Next, as shown in FIG. 4 (b), the steel plate 1 having been drilled is placed on the steel plate 2, the steel plates 1 and 2 are aligned, and tack welding is performed to bring the steel plates 1 and 2 into close contact with each other. I do. 3. Next, as shown in FIG.
Fillet welding is performed by AW) or semi-automatic welding (GMAW). 5 indicates fillet.

[0005] According to the above-described procedure, the lap members (steel plates 1 and 2) are welded.

[0006]

However, in the above-mentioned manual welding (SMAW) or semi-automatic welding (GMAW),
It is necessary to make a hole in the slot 3 or the slit 4 in the steel plate 1, and it is necessary to perform tack welding of the steel plates 1 and 2,
There was a problem that a lot of time and effort was required for preparation.

[0007] In manual coating welding (SMAW) or semi-automatic welding (GMAW), a welding material is required, and further, the steel plates 1 and 2 are easily deformed, and the slots 3 or the slits 4 are susceptible to welding defects. There was a problem. Accordingly, an object of the present invention is to provide a laser welding method and a laser welding method which can simplify preparation before welding and cause less deformation due to welding.

[0008]

In order to achieve the above-mentioned object, an invention according to claim 1 of the present invention is a laser welding method for welding a lap material with a laser, wherein the torch performs laser irradiation. A vehicle equipped with a laser beam is run on the overlapped material along the welded position where the laser welding is performed, and by the weight of the vehicle, at least the surface of the overlapped material at the welded position is brought into close contact with each other to perform laser welding at the welded position. It is characterized by performing.

According to the above method, at least the surface of the overlapped material at the position to be welded is brought into close contact by the weight of the vehicle, and poor welding and deformation of the overlapped material are prevented. According to a second aspect of the present invention, there is provided a laser welding apparatus for welding a lapping material with a laser, comprising a torch for irradiating a laser beam and a wire supply device, wherein the laser welding is performed on the lapping material along a position to be laser-welded. And a vehicle that performs laser welding of the position to be welded, wherein the vehicle has its own weight for bringing at least the surface of the overlapped material at the position to be welded into close contact.

[0010] According to the above configuration, due to the weight of the vehicle, close contact of at least the surface of the overlapped material at the welding position is obtained, and poor welding and deformation of the overlapped material are prevented. The invention according to claim 3 is the invention according to claim 2, wherein an object to be detected is provided on a welded position of the overlapped material, and the vehicle has the presence or absence of the object to be detected, and a center line of the vehicle. Detecting means for detecting a displacement of the detected object is provided, and the presence or absence of the detected object detected by the detecting means irradiates and cuts off the laser emitted from the torch, and the detected object detected by the detecting means And an adjusting means for controlling the direction of the laser beam emitted from the torch due to the deviation from the torch.

According to the above configuration, laser irradiation is performed based on the presence or absence of the detected object at the position to be welded, and the direction of the laser irradiated from the torch is automatically adjusted to the position to be welded. Is executed. The invention according to claim 4 is the invention according to claim 2 or claim 3, wherein the vehicle is provided with shielding means for shielding the laser light and heat emitted from the surroundings. It is.

According to the above configuration, the light and heat of the laser are shielded from the surroundings, and the safety of the worker is improved.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. The same components as those in FIG. 4 of the conventional example are denoted by the same reference numerals, and description thereof will be omitted. FIG. 1 is a side view of a vehicle that performs lap welding of a laser welding apparatus according to an embodiment of the present invention, and FIG. 2 is a plan view of a main part of the laser welding apparatus.

Reference numeral 11 denotes a vehicle for performing lap material welding.
Is equipped with wheels (rubber tires) 12 at the front and back, and the body (body)
A torch (including a wire supply device) 14 for irradiating a laser is provided below the projection 13 and between the wheels 12 and on a center line L of the vehicle 11 in the traveling direction (x direction). Preparing for. The torch 14 includes an irradiation device 17 that outputs a laser (eg, Nd; YAG laser) irradiation command signal and a stop command signal to an external laser generator 16 via a signal line 15, and the x of the vehicle 11. An adjusting device 18 for adjusting the projection port 14A in a direction (y direction) perpendicular to the direction is provided. In addition, the torch 14 is
The solid-state laser is connected to an outer laser generator 16 and guided to a torch 14 from an optical fiber 19 to irradiate the steel sheets 1 and 2 which are doubled. In the laser generator 16, the output of the laser is preset according to the properties of the two steel plates 1 and 2 to be subjected to lap welding so that the steel plates 1 and 2 have less penetration / deformation. The adjusting means includes the irradiation device 17 and the adjusting device 18.

Before starting welding on the steel sheet 1,
As shown in FIG. 2, a white line (an example of an object to be detected) 22 is applied to a position to be welded along a welding line 21 for performing welding. Since the positions to be welded are arranged at a predetermined length and at a predetermined pitch, the white line 22 has a broken line shape. A plurality of reflective photoelectric switches 23 are arranged below the main body (vehicle body) 13 and in front of the torch 14 in the x direction, facing the white line 22 in the y direction about the center line L. . The detection signals of these reflection-type photoelectric switches 23 are input to a detection device 24. The detection device 24 detects the presence or absence of the welding line 22 by detecting the reflected light from the white line 22, and detects the reflected light.
The deviation between the center line L of the vehicle body 13 and the white line 22 is detected based on the arrangement of the vehicle body 13.

The detection signal of the detection device 24 for the presence or absence of the white line 22 is output to the irradiation device 17 of the torch 14, and the deviation detection signal is output to the adjustment device 18. Irradiation device 17 of torch 14 is white line
When the detection signal of the presence / absence of the sensor 22 is turned on, the irradiation command signal of the solid-state laser is transmitted via the signal line 15 with a delay of a predetermined time (time during which the vehicle 11 moves the distance between the detection device 23 and the torch 14). 16 and, when turned off, outputs a solid-state laser irradiation stop command signal with a delay of the predetermined time. Further, the adjusting device 18 adjusts the projection port 14A of the torch 14 to the center of the white line 22 with the predetermined time delay based on the shift detection signal.

Also, above the main body 13 and at the front position,
Operator's driver's seat equipped with travel operating means such as steering wheel 26
27 is provided, and inside the main body 2, a traveling drive means (not shown) for driving the wheels 2 in accordance with an operation signal of the traveling operation means is provided. Further, on both side surfaces of the main body 2, a shielding plate (an example of a shielding means) 28 for shielding a space between the wheels 12 and between the main body 2 and the steel plate 1 is provided. Heat is completely blocked from the surroundings.

Further, a pair of steel rollers 29 which are rotated in contact with the steel plates 1 and 2 which are piled members are provided below the main body 13 and at the front and rear positions of the projection port 14A of the torch 14 in the x direction. Further, the vehicle 11 has its own weight, for example, about 1 ton, for bringing at least the surfaces of the steel plates 1 and 2 as the lapping members at the welding position into close contact. FIG. 3 shows a procedure of laser welding by the vehicle 11.
This will be described with reference to FIG. Step-1 First, the worker puts the steel plate 1 to be stacked on the steel plate 2 below,
Perform positioning. In addition, when cutting NC on the steel plate 1,
The white line 22 is painted. Step-2 Next, the worker moves the center of the vehicle body 13 from the end of the white line 22 to the white line.
The vehicle 11 is caused to travel at a predetermined speed along the welding line 21 so as to match the row of 22.

Then, as the vehicle 11 moves, the signal line 15
And the optical fiber 19 are sent out, and the two steel plates 1 and 2 are brought into close contact with each other by the weight of the vehicle 11 and the steel roller 29 (in particular,
When the presence or absence of the white line 22 is detected by the detecting device 24, the steel sheet 1, 2 at the welding position located below the torch 14 is closely contacted.
An irradiation command signal is output from the irradiation device 24 to the laser generator 16, and the solid-state laser generated by the laser generator 16 based on this command is transmitted to the torch 14 via the optical fiber 19.
To the steel plates 1 and 2 from the torch 14. The heat of the laser irradiation causes the weight of the vehicle 11 and the steel roller 29
The two steel plates 1 and 2 adhered to each other are welded. The detecting device 24 detects a deviation between the vehicle center line L and the white line 22, and based on the deviation, the irradiation port 14A of the torch 14
It is adjusted to the center of 22 to prevent the welding location from being shifted from the white line 22. Step-3 Then, when the operator drives the vehicle 11 along the white line 22 to the end, the operator stops the vehicle.

Thus, the welding at the welding position indicated by the white line 22 is completed. Thus, laser welding can be automatically performed based on the white line 22. According to this laser welding apparatus, welding can be performed without forming a slot or a slit for forming a steel plate connecting slit, and the steel plate 1 and the steel plate 2 are brought into close contact with each other due to the weight of the vehicle 11. , Poor welding of steel plates 1 and 2,
Deformation can be prevented, and welding can be performed without performing tack welding of the steel plates 1 and 2. Therefore,
The time and labor required for welding preparation can be significantly reduced, the delivery time can be shortened, and the burden on workers can be reduced. Also, no welding material is required, and the cost can be reduced. Further, the provision of the steel roller 29 allows the steel plates 1 and 2 to be more closely adhered to each other.

Further, by adjusting the laser output in the laser generator 16, the penetration and deformation of the steel plates 1 and 2 can be controlled, and welding defects of the steel plates 1 and 2 can be eliminated.
In addition, deformation can be minimized. Further, by providing the shielding plate 20 on the vehicle 11, the laser light and heat can be completely blocked from the surroundings, and the safety of workers can be improved.

In this embodiment, the laser generator
Although 16 is installed outside the vehicle 11, it can be provided on the vehicle 11. Further, in the present embodiment, the vehicle 11 is driven by an operator, but may be an automatic traveling vehicle that can perform automatic steering traveling while detecting the white line 22.

Further, in the present embodiment, the white line 22 is provided as an object to be detected. However, the traveling may be performed while confirming the groove of the steel plate 1 as the object to be detected. Further, in the present embodiment, the light of laser,
Although heat and heat are completely blocked from the surroundings, it is not always necessary to completely block the heat, and it is sufficient that the heat be blocked so that the safety of external workers can be ensured.

Further, in the present embodiment, the vehicle 11 is provided with the rubber tire wheel 12 and the steel roller 29. However, the steel roller 29 can be eliminated by forming the wheel 12 as a steel roller type wheel. is there. At this time, it is desirable to provide the steel roller type wheel as close as possible to the projection port 14A of the torch 14.

[0025]

As described above, according to the present invention, due to the weight of the vehicle, close contact of the overlapped material can be obtained, and poor welding and deformation of the overlapped material can be prevented.

[Brief description of the drawings]

FIG. 1 is a side view of a vehicle that performs lap welding of a laser welding apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view of a main part of the laser welding apparatus.

FIG. 3 is a flowchart showing a welding procedure by the laser welding apparatus.

FIG. 4 is a plan view and a sectional view of a lapping material for explaining a conventional method of welding the lapping material.

[Explanation of symbols]

 1, 2 Steel plate (lapping material) 11 Vehicle 12 Wheel 13 Body 14 Torch 15 Signal line 16 Laser generator 17 Irradiation device 18 Adjustment device 19 Optical fiber 21 Welding line 22 White line (detected object) 23 Photoelectric switch 24 Detection device 28 Shielding plate 29 steel roller

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Yoshinobu Nakamura, 1-7-89, Minamikohoku, Suminoe-ku, Osaka-shi, Osaka Inside Hitachi Zosen Corporation (72) Inventor Shigeo Arakane 1-chome, Minamikohoku, Suminoe-ku, Osaka-shi, Osaka No. 7-89 F-term in Hitachi Zosen Corporation (reference) 2F065 AA15 AA17 AA20 BB01 CC06 CC15 DD12 DD15 FF44 JJ05 LL02 PP22 TT07 4E068 BF00 CA17 CA18 CC01 DA14 DB01

Claims (4)

[Claims] 1. A laser welding method for welding an overlapped material with a laser, wherein a vehicle equipped with a torch for irradiating a laser travels on the overlapped material along a welded position where laser welding is performed. A laser welding method, wherein laser welding of a welded position is performed by bringing at least a surface of a welded position of a lap material into close contact with each other by the weight of a vehicle. 2. A laser welding apparatus for welding an overlapped material with a laser, comprising a torch for irradiating a laser and a wire supply device, running on the overlapped material along a welded position for performing laser welding, A laser welding apparatus comprising: a vehicle that performs laser welding at a position to be welded, wherein the vehicle has its own weight that makes at least the surface of the overlapped material at the position to be welded adhered. 3. An object to be detected is provided on a position to be welded of the overlapped material, and the vehicle is provided with a detecting means for detecting the presence or absence of the object to be detected and a deviation between a center line of the vehicle and the object to be detected. Depending on the presence or absence of the object to be detected by the detection means,
Adjustment means for irradiating and shutting off the laser emitted from the torch, and controlling the direction of the laser emitted from the torch according to a deviation from the object to be detected detected by the detection means, is provided. The laser welding apparatus according to claim 2. 4. The laser welding apparatus according to claim 2, wherein the vehicle is provided with shielding means for shielding the light and heat of the irradiated laser from the surroundings.