JP2004105973A - Automatic laser beam welding apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic laser beam welding apparatus with which the automatic welding can be performed to a cylindrical work 6. <P>SOLUTION: This automatic laser beam welding apparatus is provided with a light fiber 3 for transmitting the laser beam output from a laser beam oscillator 2 to a welding head 4, a shifting means 5 for shifting a position of the welding head, a CCD camera 8 and a height sensor 9 for recognizing the shape of the cylindrical work 6, a table 3 for work, supporting the cylindrical work 6, an articulated robot 17 for handling, performing carrying-in/carrying-out of the cylindrical work 6 to the table 31 for work and a controlling means 10 for controlling the relative position of the welding head 4 to the cylindrical work 6 to a prescribed position based on the information of the CCD camera 8 and the height sensor 9. Thus, the automatic laser beam welding apparatus, with which the cylindrical work 6 can automatically be welded, is used. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an automatic laser welding apparatus, and is intended to enable automatic welding to an object to be welded, particularly a cylindrical / columnar part or a part in the manufacturing process thereof.
[0002]
[Prior art]
Laser light is extremely directional and has a large energy, and is used for precise welding, cutting, drilling, surface modification treatment, etc. by focusing on a small point.
[0003]
In this case, pulse wave laser light (PW) or continuous wave laser light (CW) is used depending on the material of the workpiece and the processing technique. Generally, pulse wave laser light has a short duration, so it is suitable for drilling minute holes or spot welding without affecting the surroundings. Suitable for machining such as welding.
[0004]
A YAG laser oscillator, which is a kind of solid-state laser oscillator, uses a YAG (yttrium, aluminum, garnet) crystal doped with Nd as a laser single crystal, and a laser beam having a wavelength of 1.064 μm is converted into a pulse wave laser beam or a continuous laser beam. Output as wave laser light. Since YAG laser light is infrared laser light having a wavelength of 1.064 μm, transmission using an optical fiber is possible.
[0005]
As a result, in a welding apparatus or cutting apparatus using a YAG laser oscillator, laser light can be routed by an optical fiber, and the degree of freedom in design and arrangement is great.
[0006]
When laser welding is performed with such a laser welding apparatus, welding with a deep penetration depth can be performed in a narrow welding range. This is because the laser beam has a very strong light condensing property, and the laser beam functions as a powerful concentrated heat source with an extremely high energy density.
[0007]
For example, when welding a workpiece such as a fuel outlet member of a combustor, which is a high-temperature part of a cylindrical or columnar gas turbine, using a laser welding apparatus, the workpiece is used using a rotary chuck such as a lathe or a small turntable. Is fixed, the position is fixed by moving the welding head to a predetermined position of the welding target portion, and the work chuck device is rotated at an appropriate speed to perform the processing.
[0008]
In addition, a technique for holding a laser welding apparatus in a welding robot and storing a movement locus of the laser welding apparatus in advance by teaching or the like (see, for example, Patent Document 1) is applied to a workpiece of a cylindrical or cylindrical part or a part in its manufacturing process. It is also possible to apply to this.
[0009]
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-42775
[Problems to be solved by the invention]
However, in the prior art, operations such as loading a workpiece, fixing the workpiece, moving and teaching the welding head with respect to the welded portion, and unloading the workpiece after processing have been performed by the operator's hands. These operations are carried in heavy objects and YAG laser irradiation environment, and the work environment is poor and the productivity is low.
[0011]
The present invention has been made in view of the above circumstances, and an automatic laser welding apparatus capable of automatically welding a workpiece, in particular, a cylindrical / columnar gas turbine part or a part in the manufacturing process thereof. The purpose is to provide.
[0012]
[Means for Solving the Problems]
The automatic laser welding apparatus of the present invention that solves the above problems is
A laser oscillator that outputs laser light;
An optical fiber that transmits the laser beam output from the laser oscillator to the welding head;
Moving means for moving the position of the welding head;
Shape recognition means for recognizing the shape of the work piece;
A workpiece support means for supporting the workpiece,
Handling means for carrying in and out the workpiece to and from the workpiece support means;
And a control means for controlling the relative position of the welding head with respect to the workpiece to a predetermined position based on the information of the shape recognition means.
[0013]
Moreover, in the automatic laser welding apparatus according to claim 1,
There are multiple laser oscillators that output laser light.
The optical fiber is characterized in that the laser beams from the respective laser oscillators are individually and combined and transmitted to the welding head.
[0014]
Moreover, in the automatic laser welding apparatus according to claim 1,
Equipped with multiple welding heads with different laser light outputs,
The control means has a function of selecting a welding head according to the condition of the workpiece, and operates the moving means so as to control the selected welding head to a predetermined position.
[0015]
Moreover, in the automatic laser welding apparatus according to any one of claims 1 to 3,
The shape recognizing means is an image pickup means for obtaining an image by photographing an object to be welded.
[0016]
Moreover, in the automatic laser welding apparatus according to any one of claims 1 to 3,
The shape recognition means is a height sensor that detects the distance between the workpiece and the welding head by contacting the workpiece.
[0017]
Moreover, in the automatic laser welding apparatus according to any one of claims 1 to 5,
The laser oscillator is a YAG laser oscillator.
[0018]
Moreover, in the automatic laser welding apparatus as described in any one of Claims 1 thru | or 6,
The work piece is a cylindrical or columnar part or a part in the manufacturing process thereof.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an overall configuration of an automatic laser welding apparatus according to an embodiment of the present invention, and FIG. 2 shows a schematic configuration of a welding head.
[0020]
As shown in FIGS. 1 and 2, the laser welding apparatus 1 includes a YAG laser oscillator 2 that outputs laser light, and the laser light output from the YAG laser oscillator 2 is welded via a connector 15 by an optical fiber 3. It is transmitted to the processing head 4. The welding head 4 is held by a moving means (for example, a direct welding robot) 5 and is moved to an arbitrary position by the moving means 5.
[0021]
Further, the laser welding apparatus 1 is provided with a CCD camera 8 and a height sensor 9 as shape recognition means for recognizing the shape of the cylindrical workpiece 6 as an object to be welded.
The CCD camera 8 is provided with an illumination device capable of adjusting the illuminance.
[0022]
The shape recognition means is not limited to the CCD camera 8 and the height sensor 9, and any sensor such as a contact type or a contacted type can be applied as long as the shape of the cylindrical workpiece 6 can be recognized. .
[0023]
As shown in FIG. 1, a work table 31 and a work table 32 are provided as workpiece support means, and are appropriately selected and used according to the size and shape of the cylindrical work 6. On the other hand, a work stocker cart 13 and a work stocker cart 14 are provided, and are appropriately selected and used according to the size and shape of the cylindrical workpiece 6.
[0024]
The cylindrical workpiece 6 carried into the workpiece stocker carriage 13 and the workpiece stocker carriage 14 is conveyed to the workpiece table 31 and the workpiece table 32 by the handling articulated robot 17 as handling means.
[0025]
The CCD camera 8 takes an image of the cylindrical work 6 supported by the work table 31 and the work table 32, and the height sensor 9 is the cylindrical work 6 supported by the work table 31 and the work table 32 and the welding head. 4 is detected, and the shape of the cylindrical workpiece 6 is recognized.
[0026]
The photographing result of the CCD camera 8 and the detection result of the height sensor 9 are input to the control means 10, and based on the input result, the control means 10 moves to the moving means 5 so as to control the welding head 4 to a predetermined position. In addition to outputting the command, the command is output so that the work table 31 and the work table 32 perform the necessary posture drive.
[0027]
That is, the relative position of the welding head 4 with respect to the cylindrical workpiece 6 is controlled to a predetermined position based on information from the CCD camera 8 and the height sensor 9 which are shape recognition means.
[0028]
That is, as shown in FIG. 2, the position of the welding target line 7 in the horizontal direction and the groove condition are determined from the photographing result of the CCD camera 8, and the height to the welding target line 7 is determined by the height sensor 9. Based on these determination results, the position of the welding head 4 and the postures of the work table 31 and the work table 32 are controlled so that the laser beam 12 from the welding head 4 is focused on the welding target line 7. .
[0029]
In the laser welding apparatus 1 configured as described above, the cylindrical workpiece 6 is loaded on the work stocker carriage 13 or the work stocker carriage 14 outside the laser light shielding wall 20.
In this case, a worker's hand or a handling robot (not shown) is used. The work stocker cart 13 or the work stocker cart 14 is moved to a predetermined position of the laser welding apparatus 1 to fix the position of the work stocker cart 13 or the work stocker cart 14.
[0030]
Automatic operation is started in this state.
[0031]
The cylindrical work 6 is moved to the work table 31 or the work table 32 by the multi-joint robot 17 for handling and chucked. The posture of the work table 31 or the work table 32 is moved and the welding head 4 is moved to a predetermined position.
[0032]
Further, the horizontal position and groove state of the welding target line 7 are determined from the photographing result of the CCD camera 8, and the height to the welding target line 7 is determined by the height sensor 9, and based on these determination results. Thus, the position of the welding head 4 and the postures of the work table 31 and the work table 32 are controlled so that the laser beam 12 from the welding head 4 is focused on the welding target line 7.
[0033]
Thereby, the position and the posture of the work table 31 and the work table 32 are controlled so that the laser beam 12 from the welding head 4 is focused on the welding target line 7, and the cylindrical work 6 is automatically welded. Is done.
[0034]
After the welding is completed, the cylindrical work 6 that has been processed by the handling articulated robot 17 is moved to the work stocker carriage 14 or the work stocker carriage 13, and the new cylindrical work 6 is moved from the work stocker carriage 13 or the work stocker carriage 14. Move to work table 31 or work table 32 for chucking.
[0035]
After the welding process described above is repeated for a predetermined number of cylindrical workpieces 6 and the processing of the stocked cylindrical workpieces 6 is completed, the workpiece stocker carriage 14 or the workpiece stocker carriage 13 in which the processed cylindrical workpieces 6 are accommodated is attached. The cylindrical workpiece 6 is transshipped by moving it outside the laser light shielding wall 20.
[0036]
The series of operations described above enables automatic laser welding of the cylindrical workpiece 6. As a result, it is possible to provide an automatic laser welding apparatus capable of automatically welding an object to be welded, particularly a cylindrical / columnar part and a part in the manufacturing process thereof. As the cylindrical / columnar parts, for example, high-temperature parts of a gas turbine (combustor fuel supply system parts, etc.) can be applied.
[0037]
FIG. 3 shows a schematic configuration of the YAG laser oscillator 2. For example, the connector 15 can connect three types of optical fibers. For example, as shown in FIG. 3, the YAG laser oscillator 2 includes three types of YAG laser oscillators 2a, 2b, and 2c.
[0038]
The optical fibers from the YAG laser oscillators 2a, 2b and 2c are respectively connected to the low output optical fiber 3a (see FIG. 3A), and the optical fibers from the YAG laser oscillators 2a and 2b are bundled together. A medium output optical fiber 3b connected to each other (see FIG. 3B), and a high output optical fiber 3c connected by bundling optical fibers from the YAG laser oscillators 2a, 2b, 2c (FIG. 3C )) Is connected as appropriate.
[0039]
The operator connects the optical fiber 3 corresponding to the target cylindrical workpiece 6 (according to the required welding depth) to the connector 15. By detecting the welding object line 7 based on the plane condition by the CCD camera 8 and the height condition by the height sensor 9, the output of the optical fiber 3 connected in advance matches the output to the detected welding object line 7. It can be confirmed whether or not If a mismatch is confirmed, an optical fiber suitable for the output required before the work can be connected.
[0040]
FIG. 4 shows a schematic configuration of a welding head according to another embodiment of the present invention. The same members as those shown in FIGS. 1 to 3 are denoted by the same reference numerals.
[0041]
As shown in the figure, YAG laser oscillators 2a, 2b, 2c that output laser light are provided (see FIG. 3), and laser light output from the YAG laser oscillators 2a, 2b, 2c is transmitted by optical fibers 3a, 3b, 3c. The data is transmitted to the welding heads 21a, 21b, and 21c via the connector 15.
[0042]
The welding heads 21a, 21b, 21c are held by the moving means 5, and the required welding work heads 21a, 21b, 21c are positioned and moved by the moving means 5 to arbitrary positions.
[0043]
The optical fiber 3 includes a low-power optical fiber 3a to which optical fibers from the YAG laser oscillators 2a, 2b, and 2c are individually connected (see FIG. 3A), and optical fibers from the YAG laser oscillators 2a and 2b are bundled together. A medium output optical fiber 3b connected to each other (see FIG. 3B), and a high output optical fiber 3c connected by bundling optical fibers from the YAG laser oscillators 2a, 2b, 2c (FIG. 3C ))).
[0044]
The photographing result of the CCD camera 8 and the detection result of the height sensor 9 are input to the control means 10, and the control means 10 selects and selects the welding heads 21a, 21b, 21c used for welding based on the input result. A movement command is output to the moving means 5 so as to control the welding head 21 to a predetermined position.
[0045]
That is, the horizontal position and groove state of the welding target line 7 are determined from the photographing result of the CCD camera 8, and the height to the welding target line 7 is determined by the height sensor 9, and based on these determination results. The welding heads 21a, 21b, and 21c are selected and selected so that the laser beam 12 from the welding head 21 corresponding to a predetermined welding depth is focused on the welding target line 7. The position is controlled.
[0046]
In the laser welding apparatus 1 having the above-described configuration, the CCD camera 8 and the height sensor 9 are lowered while the cylindrical workpiece 6 is rotated, and the image status (plane position, etc.) of the welding target line 7 and the height of the welding target line 7 are measured. The situation is recognized and input to the control means 10. At this time, the diameter of the cylindrical workpiece 6 is recognized by the height sensor 9.
[0047]
A welding head 21 corresponding to a predetermined welding depth (corresponding to the diameter of the cylindrical workpiece 6) is selected from the control means 10 based on the image state of the welding target line 7 and the height state of the welding target line 7. A movement command is output to the moving means 5.
[0048]
Accordingly, the positions of the welding heads 21a, 21b, and 21c are controlled so that the laser beam 12 from the welding head 21 corresponding to the diameter of the cylindrical workpiece 6 is focused on the welding target line 7. Also, the operator can manually adjust the welding status by checking the image.
[0049]
Based on the plane condition by the CCD camera 8 and the height condition by the height sensor 9, the welding head 21 corresponding to the diameter of the cylindrical workpiece 6 is selected by automatically following the welding target line 7, and the position and height in the plane direction are selected. Directional position (ie, three-dimensional position) can be controlled. By recognizing the plane state by image processing, the operator can confirm the actual welding target line 7.
[0050]
Accordingly, the welding point 7 and the condensing point (irradiation point) of the laser beam 12 of the welding head 21 corresponding to the diameter of the cylindrical workpiece 6 can be automatically matched, and the operation set in advance by teaching or the like can be performed. For example, correction can be performed. Thereby, even if it applies to welding of the cylindrical workpiece 6 from which a diameter differs, the required welding head 21 can be selected and welding along the welding object line 7 is attained, and stable welding quality can be maintained.
[0051]
As a result, it is possible to provide an automatic laser welding apparatus capable of automatically welding a workpiece to be welded, particularly a cylindrical / columnar part or a part in the process of manufacturing, to a different kind of workpiece. It becomes possible.
[0052]
The number of welding heads 21 is not limited to three, and two or four or more can be applied.
[0053]
【The invention's effect】
The laser welding apparatus of the present invention is
A laser oscillator that outputs laser light;
An optical fiber that transmits the laser beam output from the laser oscillator to the welding head;
Moving means for moving the position of the welding head;
Shape recognition means for recognizing the shape of the work piece;
A workpiece support means for supporting the workpiece,
Handling means for carrying in and out the workpiece to and from the workpiece support means;
Control means for controlling the relative position of the welding head with respect to the workpiece to a predetermined position based on the information of the shape recognition means,
It is possible to provide an automatic laser welding apparatus capable of automatically performing welding on the workpiece.
[0054]
Moreover, in the automatic laser welding apparatus according to claim 1,
There are multiple laser oscillators that output laser light.
Because the optical fiber is transmitted individually and combined with the laser light from each laser oscillator to the welding head,
Laser beams with different outputs can be used.
[0055]
Moreover, in the automatic laser welding apparatus according to claim 1,
Equipped with multiple welding heads with different laser light outputs,
The control means has a function of selecting the welding head according to the condition of the workpiece, and the moving means is operated so as to control the selected welding head to a predetermined position.
It can be used for different types of welds.
[0056]
Moreover, in the automatic laser welding apparatus according to any one of claims 1 to 3,
Since the shape recognition means is an image pickup means for obtaining an image by photographing an object to be welded,
The welded part can be recognized visually.
[0057]
Moreover, in the automatic laser welding apparatus according to any one of claims 1 to 3,
Since the shape recognition means is a height sensor that detects the distance between the workpiece and the welding head by contacting the workpiece,
The distance can be detected reliably.
[0058]
Moreover, in the automatic laser welding apparatus according to any one of claims 1 to 5,
Since the laser oscillator is a YAG laser oscillator,
It can be applied to YAG laser welding.
[0059]
Moreover, in the automatic laser welding apparatus as described in any one of Claims 1 thru | or 6,
Since the work piece is a cylindrical or columnar part or a part in its manufacturing process,
Automatic welding of cylindrical / cylindrical parts or parts in the manufacturing process becomes possible.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of an automatic laser welding apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic configuration diagram of a welding head.
FIG. 3 is a schematic configuration diagram of a YAG laser oscillator 2;
FIG. 4 is a schematic configuration diagram of a welding head according to another embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Laser welding apparatus 2 YAG laser oscillator 3 Optical fiber 4 Welding head 5 Moving means 6 Cylindrical work 7 Welding object line 8 CCD camera 9 Height sensor 10 Control means 31, 32 Work table 13, 14 Work stocker cart 15 Connector 17 Handling Articulated robot 20 Laser shading wall 21 Welding head

Claims (7)

A laser oscillator that outputs laser light;
An optical fiber that transmits the laser beam output from the laser oscillator to the welding head;
Moving means for moving the position of the welding head;
Shape recognition means for recognizing the shape of the work piece;
A workpiece support means for supporting the workpiece,
Handling means for carrying in and out the workpiece to and from the workpiece support means;
An automatic laser welding apparatus comprising: control means for controlling the relative position of the welding head with respect to the workpiece to a predetermined position based on information of the shape recognition means. In the automatic laser welding apparatus of Claim 1,
There are multiple laser oscillators that output laser light.
An automatic laser welding apparatus characterized in that an optical fiber transmits laser beams from respective laser oscillators individually and combined to a welding head. In the automatic laser welding apparatus of Claim 1,
Equipped with multiple welding heads with different laser light outputs,
An automatic laser welding apparatus characterized in that the control means has a function of selecting a welding head according to the condition of the workpiece and operates the moving means so as to control the selected welding head to a predetermined position. In the automatic laser welding apparatus according to any one of claims 1 to 3,
An automatic laser welding apparatus, wherein the shape recognizing means is an imaging means for photographing an object to be welded to obtain an image. In the automatic laser welding apparatus according to any one of claims 1 to 3,
An automatic laser welding apparatus, wherein the shape recognition means is a height sensor that detects a distance between a workpiece and a welding head by contacting the workpiece. In the automatic laser welding apparatus according to any one of claims 1 to 5,
An automatic laser welding apparatus characterized in that the laser oscillator is a YAG laser oscillator. In the automatic laser welding apparatus according to any one of claims 1 to 6,
An automatic laser welding apparatus characterized in that the workpiece is a cylindrical or columnar part or a part in its manufacturing process.

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