Three-dimensional position detection device and welding machine using the same

Abstract

To provide a three-dimensional position detection device and a welding machine that can detect positions more simply.SOLUTION: A first irradiation unit 11 of a welding machine 10 emits a first light beam 17 that allows a mark to be visualized to a workpiece 31 of a portion applied with the mark. A second irradiation unit 12 emits a second light beam 18 onto the workpiece 31. An imaging unit 13 images the workpiece 31 of the portion applied with the mark to generate a first image 19, and images the workpiece 31 under irradiation of the second light beam 18 to generate a second image 20. A welding unit 14 performs welding on the workpiece 31. A drive unit 15 changes the three-dimensional position and posture of the welding unit 14. A calculation control unit 16 performs welding on the workpiece 31 of the portion applied with the mark by using the welding unit 14 on the basis of the welding position information 21.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a three-dimensional position detection device and a welding machine using the same, and more particularly to a welding machine capable of easily identifying a welding point. [Background technology]

[0002] One of the fields in which 3D position detection devices can be applied is welding, which is a method of integrating parts by applying heat to the joints between the parts.

[0003] In recent years, methods have been developed for using robots to perform welding in the manufacturing process of vehicles, etc. In the invention described in Patent Document 1, a welding torch is provided at the tip of an articulated robot, and welding is performed on an object to be welded, such as a car body, that is provided at a predetermined location. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-094581 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the above-mentioned three-dimensional position detection device and welding machine using image processing technology have room for improvement in terms of making welding easier.

[0006] For example, when welding is performed inside a factory such as an automobile factory, the positions of the workpiece and the welding machine are determined in advance, so it is easy to identify the relative positions of the two.

[0007] On the other hand, welding is performed in various situations. For example, when a welding machine is introduced to weld reinforcing bars at a civil engineering or construction site, it is necessary to identify the relative position of the reinforcing bars with respect to the welding machine. However, there is a problem that the measurement work is very complicated when measuring and identifying the reinforcing bars with respect to the welding machine for only one welding. In addition, there is a problem that it is difficult to introduce the welding machine if the workers working at the construction site are not familiar with the measurement work.

[0008] Furthermore, with the declining birthrate and aging population, it is becoming difficult to secure skilled welders at civil engineering and construction sites, and there is a strong demand for welding robots to solve this problem.

[0009] Furthermore, problems associated with detecting three-dimensional positions can occur not only in welding but also in other fields such as appearance quality inspection.

[0010] The present invention has been made in consideration of the above problems, and an object of the present invention is to provide a three-dimensional position detection device and a welding machine that can detect a position more easily. [Means for solving the problem]

[0011] The three-dimensional position detection device of the present invention is a three-dimensional position detection device that detects the position of an object to which a mark is attached, and is equipped with a first irradiation unit, a second irradiation unit, an imaging unit, and an arithmetic and control unit, wherein the first irradiation unit irradiates the object to the portion to which the mark is attached with a first light ray that enables the mark to be visualized, the second irradiation unit irradiates the object to the portion to which the mark is attached with a second light ray having a different wavelength from that of the first irradiation unit, the imaging unit generates a first image by photographing the object to which the mark is attached, and generates a second image by photographing the object in a state in which the second light ray is irradiated, and the arithmetic and control unit detects the position of the mark from the first image, calculates the three-dimensional position of the mark from the second image, and calculates position information based on the three-dimensional position of the mark.

[0012] The welding machine of the present invention is a welding machine that performs welding work on a workpiece having a mark, and is equipped with a first irradiation unit, a second irradiation unit, an imaging unit, a welding unit, a drive unit, and an arithmetic and control unit, the first irradiation unit irradiates the workpiece at the portion having the mark with a first light beam that enables the mark to be visualized, the second irradiation unit irradiates the workpiece with a second light beam having a wavelength different from that of the first irradiation unit, the imaging unit generates a first image by imaging the workpiece at the portion having the mark, and the second light beam A second image is generated by photographing the workpiece in an irradiated state, the welding unit is configured to weld the workpiece, the drive unit is configured to change the three-dimensional position and posture of the welding unit, the calculation and control unit detects the position of the mark from the first image, calculates the three-dimensional position of the mark from the second image, calculates welding position information based on the three-dimensional position of the mark, and uses the welding unit to weld the workpiece at the portion to which the mark is applied based on the welding position information.

[0013] In the welding machine of the present invention, the first light beam is a UV light beam, and the mark can be viewed by visible light beams by irradiating the mark with the first light beam.

[0014] In the welding machine of the present invention, the welding position information includes a welding start position, a welding route, and a welding end position. Effect of the Invention

[0015] The three-dimensional position detection device of the present invention is a three-dimensional position detection device that detects the position of an object to which a mark is attached, and includes a first irradiation unit, a second irradiation unit, an image capture unit, and an arithmetic and control unit, the first irradiation unit irradiates the object to which the mark is attached with a first light beam that can visualize the mark, the second irradiation unit irradiates the object to which the mark is attached with a second light beam having a wavelength different from that of the first irradiation unit, the image capture unit generates a first image by capturing the object to which the mark is attached, and generates a second image by capturing the object in a state in which the second light beam is irradiated, and the arithmetic and control unit detects the position of the mark from the first image, calculates the three-dimensional position of the mark from the second image, and calculates position information based on the three-dimensional position of the mark. According to the three-dimensional position detection device of the embodiment of the present invention, the three-dimensional position of the marked portion can be easily and accurately calculated by image processing.

[0016] The welding machine of the present invention is a welding machine that performs welding work on a workpiece having a mark, and is equipped with a first irradiation unit, a second irradiation unit, an imaging unit, a welding unit, a drive unit, and an arithmetic and control unit, the first irradiation unit irradiates the workpiece at the portion having the mark with a first light beam that enables the mark to be visualized, the second irradiation unit irradiates the workpiece with a second light beam having a wavelength different from that of the first irradiation unit, the imaging unit generates a first image by imaging the workpiece at the portion having the mark, and the second light beam The second image is generated by photographing the workpiece in an irradiated state, the welding unit is configured to weld the workpiece, the driving unit is configured to change the three-dimensional position and posture of the welding unit, and the calculation control unit detects the position of the mark from the first image, calculates the three-dimensional position of the mark from the second image, calculates welding position information based on the three-dimensional position of the mark, and uses the welding unit to weld the workpiece at the part to which the mark is applied based on the welding position information. According to the welding machine of the embodiment of the present invention, the workpiece at the part to which the mark is applied can be easily welded. Therefore, at a construction site or the like, the relative position between the workpiece and the welding machine can be easily specified, and welding work can be easily and accurately performed. In addition, the relative position is semi-automatically determined by image processing, making it possible to perform high-quality welding without the need for skilled work.

[0017] In addition, in the welding machine of the present invention, the first light is a UV light, and the mark can be viewed with visible light by irradiating the first light. According to the welding machine of the embodiment of the present invention, even if a mark remains on the workpiece after welding is completed, the mark is usually not visible with visible light, so that the mark does not deteriorate the appearance of the workpiece.

[0018] In the welding machine according to the present invention, the welding position information includes a welding start position, a welding route, and a welding end position. According to the welding machine according to the embodiment of the present invention, the welding of the workpiece can be performed accurately. [Brief description of the drawings]

[0019] [Figure 1] 1 is a side view showing an entire welding machine according to an embodiment of the present invention; [Diagram 2] 1 is a perspective view showing an entire welding machine according to an embodiment of the present invention; [Diagram 3] 1 is a side view partially illustrating a welding machine according to an embodiment of the present invention. [Figure 4] 4 is a flowchart illustrating a method of performing welding using a welding machine according to an embodiment of the present invention. [Figure 5A] FIG. 4 is a side view showing a step of applying a first mark in a method of performing welding using a welding machine according to an embodiment of the present invention. [Figure 5B] FIG. 2 is a top view showing a step of applying a first mark in a method of performing welding using a welding machine according to an embodiment of the present invention. [Figure 6A] 10 is a side view showing a step of photographing a first mark in a method of performing welding using a welding machine according to an embodiment of the present invention. FIG. [Figure 6B] 10 is a top view showing a step of photographing a first mark in a method of performing welding using a welding machine according to an embodiment of the present invention. FIG. [Figure 7A] 11 is a side view showing a step of photographing a second mark in a method of performing welding using a welding machine according to an embodiment of the present invention. FIG. [Figure 7B] 11 is a top view showing a step of photographing a second mark in a method of performing welding using a welding machine according to an embodiment of the present invention. FIG. [Figure 8] 5 is a schematic diagram showing the principle of calculating the position of a reference plane in a method of performing welding using a welding machine according to an embodiment of the present invention. FIG. [Figure 9A] 1 is a side view showing a step of performing welding in a method of performing welding using a welding machine according to an embodiment of the present invention. FIG. [Figure 9B] FIG. 2 is a top view showing a step of performing welding in a method of performing welding using a welding machine according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, a welding machine 10 according to an embodiment of the present invention and a welding method using the same will be described in detail with reference to the drawings. In the following description, the same components are in principle given the same reference numerals, and repeated description will be omitted. Here, the welding machine 10 according to this embodiment is an example of a three-dimensional position detection device. In addition, other equipment can be used as an example of the three-dimensional position detection device, such as an inspection device.

[0021] FIG. 1 is a side view showing an entire welding machine 10. As shown in FIG.

[0022] As described below, welding machine 10 is a welding machine that performs a welding operation on workpiece 31, which is an object to which a mark is applied. Welding machine 10 is an articulated robot for welding. Specifically, welding machine 10 includes first irradiation unit 11, second irradiation unit 12, imaging unit 13, welding unit 14, drive unit 15, and calculation control unit 16. Here, first irradiation unit 11, second irradiation unit 12, and imaging unit 13 will be described later with reference to FIG. 2 and subsequent figures.

[0023] The welding machine 10 is fixed to the upper surface of a pedestal 22. The pedestal 22 is provided with casters at its lower end so that it can be moved. Since the pedestal 22 is movable, when the welding machine 10 is used at a construction site or the like, for example, a worker can move the pedestal 22 to easily bring the welding machine 10 closer to steel plates and reinforcing bars installed at the construction site. In addition, by moving the pedestal 22, a worker can easily roughly align the welding machine 10 with a workpiece 31, which will be described later.

[0024] The driving unit 15 is configured to be able to change the three-dimensional position and posture of the welding portion 14 and the storage portion 23. For example, a commercially available articulated robot arm can be used as the driving unit 15. Specifically, the driving unit 15 has, from the lower side, a first support portion 151, a first joint portion 152, a second support portion 153, a second joint portion 154, a first arm portion 155, a third joint portion 156, and a second arm portion 157. The first support portion 151 is fixed to the upper surface of the base 22. The first joint portion 152 is disposed between the first support portion 151 and the second support portion 153, and the second support portion 153 is allowed to rotate around an axis extending along the up-down direction. The second joint portion 154 is disposed between the second support portion 153 and the lower end of the first arm portion 155, and the first arm portion 155 is allowed to rotate around an axis extending along the left-right direction. The third joint portion 156 is disposed between the upper end of the first arm portion 155 and the rear end of the second arm portion 157, and the second arm portion 157 is rotatable about an axis extending in the left-right direction. With the driving portion 15 configured as described above, the three-dimensional positions and orientations of the accommodation portion 23 and the welding portion 14 fixed to the tip portion of the driving portion 15 can be freely adjusted.

[0025] Cylinder 24 is attached to the upper front end of second arm portion 157. Cylinder 24 is an intermediate member for attaching accommodating portion 23 to the front end of second arm portion 157. Cylinder 24 supports accommodating portion 23 in a state in which it can slide along the longitudinal direction of second arm portion 157.

[0026] The accommodation section 23 is a substantially box-shaped member that accommodates various components for aligning the welded portion 14. The accommodation section 23 and the components will be described later with reference to FIG.

[0027] The welding portion 14 is configured to be able to weld the workpiece 31, which will be described later. The welding portion 14 is configured to be able to perform arc welding, electron beam welding, gas welding, and laser welding. The welding portion 14 is installed below the front end of the second arm portion 157. The welding portion 14 is connected to a welding machine main body, not shown.

[0028] The arithmetic control unit 16 is composed of a semiconductor element such as a CPU (Central Processing Unit). The arithmetic control unit 16 may include a semiconductor storage device such as a RAM (Random Access Memory) or a ROM (Read Only Memory) as a storage unit. Such a storage unit stores programs, parameters, etc. The arithmetic control unit 16 executes functions and methods described below based on the programs, parameters, etc. read from the storage unit.

[0029] As described later, the calculation control unit 16 detects the position of a first mark 301 (described later) from a first image 19 (described later). Furthermore, the calculation control unit 16 calculates a three-dimensional position of a second mark 302 (described later) from a second image 20 (described later). Furthermore, the calculation control unit 16 calculates welding position information 21, which is an example of position information (described later), based on the three-dimensional position of the second mark 302 (described later). Furthermore, the calculation control unit 16 welds the portion of the workpiece 31 to which the mark is applied, using the welding unit 14, based on the welding position information 21 (described later). This matter will be described later with reference to FIG. 4 and subsequent figures.

[0030] FIG. 2 is a perspective view showing the entire welding machine 10. As shown in FIG.

[0031] Here, a first workpiece 311 and a second workpiece 312 are exemplified as the workpiece 31. The first workpiece 311 and the second workpiece 312 are, for example, thick iron plates used at construction sites. The second workpiece 312 is placed on the upper surface of the first workpiece 311. As will be described later, the welding machine 10 welds the rear side of the second workpiece 312 to the upper surface of the first workpiece 311.

[0032] FIG. 3 is a side view partially showing the housing portion 23 of the welding machine 10. As shown in FIG.

[0033] Inside the storage section 23, the first irradiating section 11, the second irradiating section 12, the photographing section 13, etc. are stored.

[0034] The storage section 23 is a substantially box-shaped member formed by forming a steel plate or the like into a predetermined shape. The opening 232 is formed by opening the front lower end of the storage section main body 231. In addition, a lid section 233 is disposed at the lower front end of the storage section main body 231 and immediately adjacent to the opening 232. The lid section 233 is a substantially plate-shaped member, and its lower side is rotatably connected to the storage section main body 231. By opening the lid section 233, each light beam can be emitted from the first irradiation section 11 and the second irradiation section 12 through the opening 232. In addition, the photographing section 13 can photograph the workpiece 31, the first mark 301, and the second mark 302 described later through the opening 232. In addition, when welding is performed by the welding section 14, the lid section 233 closes the opening 232. This makes it possible to prevent dust and the like generated during welding from entering the storage section 23.

[0035] The first irradiation unit 11 is configured to irradiate the first light beam 17 to the workpiece 31 at the portion where the first mark 301 is applied. Here, the first light beam 17 is a UV light beam that makes it possible to visualize the first mark 301 described later. When viewed from above, the first irradiation unit 11 is formed in a substantially ring shape with a hollow portion formed in the center. The photographing unit 13 is disposed above the hollow portion of the first irradiation unit 11 and photographs the downward direction through the hollow portion.

[0036] The second irradiating unit 12 is configured to irradiate the workpiece 31 with a second light beam 18 having a wavelength different from that of the first irradiating unit 11. For example, the second irradiating unit 12 is a line laser that irradiates a laser beam that extends linearly along the left-right direction.

[0037] The photographing unit 13 is a camera that photographs the downward direction using visible light. The photographing unit 13 is disposed directly above the first irradiation unit 11 inside the storage unit 23. As described later, the photographing unit 13 generates a first image 19 by photographing a portion of the workpiece 31 to which the first mark 301 is applied. Furthermore, as described later, the photographing unit 13 generates a second image 20 by photographing the workpiece 31 in a state in which the second light beam 18 is irradiated. The matters concerned will be described in detail with reference to FIG. 4 and subsequent figures.

[0038] FIG. 4 is a flow chart illustrating a method of performing welding using welder 10.

[0039] In step S10, an operator fixes the workpieces. Specifically, referring to Fig. 2, an operator fixes the relative positions of first workpiece 311 and second workpiece 312. A clamp (not shown) or the like may be used for the fixation. At the same time, the operator moves welding machine 10 to the vicinity of workpiece 31 by operating pedestal 22 shown in Fig. 1.

[0040] In step S11, a worker marks the first mark 301.

[0041] Fig. 5A is a side view showing the step of applying the first mark 301. Fig. 5B is a top view showing the step of applying the first mark 301.

[0042] 5A and 5B, a case is shown here in which the second workpiece 312 is placed on the upper surface of the first workpiece 311, and the rear edge of the second workpiece 312 is welded to the upper surface of the first workpiece 311. Therefore, the first mark 301 is marked on the upper surface of the first workpiece 311 so as to follow the rear edge of the second workpiece 312. Here, the first mark 301 is shown by hatching.

[0043] A UV mark that is difficult to see with visible light and becomes visible when irradiated with a first light ray 17 (UV light) described later can be used as the first mark 301. Since the UV mark cannot be seen with visible light, even if it remains on the workpiece 31 after welding, it does not impair the aesthetic appearance of the workpiece 31.

[0044] In step S12, the arithmetic and control unit 16 captures an image of the workpiece 31 while irradiating it with the first light beam 17.

[0045] Fig. 6A is a side view showing a step of photographing the first mark 301. Fig. 6B is a top view showing a step of photographing the first mark 301.

[0046] 6A, in this step, first, the first irradiating unit 11 irradiates the first light beam 17 downward based on an instruction from the calculation control unit 16. UV light is adopted as the first light beam 17, and this allows the first mark 301 to be clearly photographed with visible light. In this state, the photographing unit 13 photographs the downward direction to generate the first image 19. The first image 19 is stored in the semiconductor storage device or the like described above.

[0047] 6B, a dotted line indicates the outer edge of the area in which the first image 19 is captured. As shown in this figure, the first mark 301 is clearly visible in the first image 19.

[0048] In step S13, the calculation control unit 16 searches for the first mark 301. Specifically, referring to Fig. 6B, the first mark 301 is clearly photographed within the first image 19. Therefore, the calculation control unit 16 can calculate the position of the rear side of the second workpiece 312 in the front-rear direction and the left-right direction by performing image analysis on the first image 19.

[0049] In step S14, the arithmetic and control unit 16 captures an image of the workpiece 31 while irradiating it with the second light beam 18.

[0050] Fig. 7A is a side view showing a step of photographing the second mark 302. Fig. 7B is a top view showing a step of photographing the second mark 302.

[0051] 7A, based on an instruction from the calculation control unit 16, the second irradiating unit 12 irradiates the second light beam 18 toward the first workpiece 311. As described above, the second irradiating unit 12 is a line laser that irradiates a laser beam linearly along the left-right direction.

[0052] 7B, a second mark 302 is formed on and near the top surface of the first workpiece 311. The second mark 302 is a mark formed by irradiation with the second light beam 18, which is a line laser. At this time, on the top surface of the first workpiece 311, the first mark 301 and the second mark 302 described above overlap each other.

[0053] There are steps between the first workpiece 311 and its periphery. Therefore, a bent portion where the second mark 302 is bent at a right angle is formed on the periphery of the first workpiece 311. In Fig. 7B, the start point of this bent portion is indicated by A1, and the end point of the bent portion is indicated by A2.

[0054] In this process, a second image 20 is generated by capturing an image using the capturing unit 13 while the second irradiating unit 12 is irradiating the second light beam 18. In Fig. 7B, the outer edge of the second image 20 is indicated by a dotted line. The second image 20 is stored in the semiconductor storage device or the like described above.

[0055] In step S15, the calculation and control unit 16 measures the distance from the welding machine 10.

[0056] 8 is a schematic diagram showing the principle of calculating the position of the reference plane in a method of performing welding using the welding machine 10. First, the calculation control unit 16 calculates A, which is the distance between A1 and A2 described above. A can be easily calculated from the number of pixels in the second image 20. Also, θ is the size of the angle formed by the second light ray 18 and the vertical side. Then, if the height of the upper surface of the pedestal 22 is known, the height B of the reference plane, which is the upper surface of the first workpiece 311, can be calculated as A×TAN(90-θ).

[0057] This makes it possible to identify the three-dimensional position of the rear side of the second workpiece 312, which is the location to be welded.

[0058] In step S16, the calculation and control unit 16 calculates the position where welding is to be performed.

[0059] 9A and 9B are side and top views showing the steps of performing welding.

[0060] 9B, the calculation control unit 16 calculates welding position information 21 based on the information calculated in the previous steps, i.e., the three-dimensional position of the rear side of the second workpiece 312. Specifically, the calculation control unit 16 calculates the three-dimensional positions of the welding start position 211, the welding route 212, and the welding end position 213.

[0061] In step S17, the calculation control unit 16 teaches position information for performing welding. Specifically, the calculation control unit 16 teaches the position information for performing welding in consideration of the three-dimensional position of the welding position information 21 and the position, posture, angle, etc. of the welding portion 14.

[0062] In step S18, the calculation and control unit 16 welds the workpiece 31. Specifically, as shown in Fig. 9A, the tip of the welding portion 14 is brought close to the welding route 212 and welding is performed. Furthermore, when welding is performed, as shown in Fig. 9B, the welding portion 14 starts welding from the welding start position 211, moves rightward along the welding route 212, and reaches the welding end position 213.

[0063] 9A, when welding is performed by welding portion 14, lid portion 233 rotates about its lower end as the center of rotation based on instructions from calculation control portion 16 to close opening 232 of housing body 231. This prevents dust generated by welding from entering inside housing portion 23. Also, cylinder 24 moves housing portion 23 upward and rearward. This prevents housing portion 23 from interfering with the welding work of welding portion 14.

[0064] In this manner, the vicinity of the rear side of the second workpiece 312 can be welded to the upper surface of the first workpiece 311.

[0065] Although the embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and modifications can be made without departing from the scope of the present invention. In addition, the above-described embodiments can be combined with each other. [Explanation of symbols]

[0066] 10. Welding machine 11 1st irradiation section 12 Second irradiation section 13. Photography Department 14 Welding 15 Drive unit 151 1st support part 152 1st joint part 153 Second support part 154 2nd joint part 155 First Arm 156 Third joint 157 Second Arm 16 Calculation control unit 17 First Ray 18 Second ray 19 1st image 20 2nd image 21 Welding position information 211 Welding start position 212 Welding Route 213 Welding end position 22 Pedestal 23 Storage unit 231 Storage unit body 232 Opening 233 Lid 24 cylinders 301 1st Mark 302 2nd Mark 31 Work 311 First Work 312 2nd Work

Claims

1. A three-dimensional position detection device that detects the position of an object to which a mark is attached, The apparatus includes a first irradiation unit, a second irradiation unit, an imaging unit, and an arithmetic and control unit, the first irradiating unit irradiates a first light beam capable of visualizing the mark onto a portion of the object to which the mark is applied; The second irradiating unit irradiates the object with a second light beam having a wavelength different from that of the first irradiating unit, the photographing unit generates a first image by photographing the object in a portion to which the mark is applied, and generates a second image by photographing the object in a state in which the second light beam is irradiated; The arithmetic and control unit is Detecting a position of the mark from the first image; Calculating a three-dimensional position of the mark from the second image; A three-dimensional position detection device which calculates position information based on the three-dimensional position of the mark.

2. A welding machine that performs welding work on a workpiece to which a mark has been applied, The apparatus includes a first irradiation unit, a second irradiation unit, an imaging unit, a welding unit, a driving unit, and a calculation control unit, The first irradiation unit irradiates a first light beam capable of visualizing the mark onto the workpiece at a portion where the mark is applied, The second irradiation unit irradiates the workpiece with a second light beam having a wavelength different from that of the first irradiation unit, The photographing unit generates a first image by photographing the workpiece of the portion to which the mark is applied, and generates a second image by photographing the workpiece in a state in which the second light beam is irradiated, The welding portion is configured to be able to weld the workpiece, The drive unit is configured to change a three-dimensional position and a posture of the welding portion, The arithmetic and control unit is Detecting a position of the mark from the first image; Calculating a three-dimensional position of the mark from the second image; Calculating welding position information based on the three-dimensional position of the mark; A welding machine characterized in that, based on the welding position information, the welding part is used to weld the workpiece at the portion to which the mark is applied.

3. the first light beam is a UV light beam, The welding machine according to claim 2 , wherein the mark is visible by irradiating the mark with the first light beam.

4. The welding machine according to claim 2 , wherein the welding position information includes a welding start position, a welding route, and a welding end position.

Images