Welder and welding method

Abstract

The present invention provides a welder which can be easily moved and which can easily detect a relative position.　An irradiation unit 11 of a welder 10 irradiates a workpiece 22 with light rays 16. An imaging unit 12 images the workpiece 22. A welding unit 13 performs welding with respect to the workpiece 22 A drive unit 14 changes the three-dimensional position and posture of the welding unit 13. A computation control unit 15 controls the irradiation unit 11 to irradiate the workpiece 22 with prescribed light rays 16, and controls the imaging unit 12 to image the workpiece 22 in the state of being irradiated with the light rays 16 so that an image 17 is formed. Furthermore, the computation control unit 15 calculates the positional relationship between the welding unit 13 and the workpiece 22 on the basis of the image 17, and controls the drive unit 14 to drive the welding unit 13. A tip of the welding unit 13 is thereby brought closer to the workpiece 22, and welding work is performed.

Description

Welding Machine and Welding Method

[0001] The present invention relates to a welding machine and a welding method, and particularly to a welding machine and a welding method capable of easily calculating the relative position of a welding point.

[0002] Welding is one of the connection methods for connecting steel plates and the like to each other. Welding is a method of integrating members by applying heat to the joint part of the members.

[0003] In recent years, in the manufacturing steps of vehicles and the like, methods of performing welding using robots have also been developed. In the invention described in Patent Document 1, a welding torch is disposed at the tip of an articulated robot, and welding work is performed on a welding object, for example, a vehicle body, disposed at a predetermined location.

[0004] Japanese Patent Application Laid-Open No. 2021-094581

[0005] However, there was room for improvement in the above-described welding machine from the viewpoint of performing welding more simply.

[0006] Specifically, for example, in a shipyard or the like, there are many welding points for welding steel plates to each other. Therefore, the operator needs to perform welding work at a large number of welding points while moving the welding machine. However, since the weight of the welding machine itself is heavy, it was not easy for the operator to move the welding machine. Also, although technologies for semi-automating welding work by using a robot arm have emerged, there is also a problem that it is not easy to detect the relative position between the robot arm and the welding point.

[0007] The present invention has been made in view of such problems, and an object of the present invention is to provide a welding machine and a welding method capable of easily performing movement and relative position detection.

[0008] The present invention relates to a welding machine for performing welding work on a workpiece, comprising: an irradiation unit; an imaging unit; a welding unit; a drive unit; and a calculation and control unit, wherein the irradiation unit is configured to irradiate the workpiece with a light ray; the imaging unit is configured to photograph the workpiece; the welding unit is configured to perform welding on the workpiece; the drive unit is configured to change the three-dimensional position and orientation of the welding unit; the calculation and control unit irradiates the workpiece with a predetermined light ray from the irradiation unit, forms an image by photographing the workpiece with the imaging unit while the light ray is irradiated, calculates the positional relationship between the welding unit and the workpiece based on the image, and drives the welding unit with the drive unit to bring the tip of the welding unit closer to the workpiece and perform welding work.

[0009] Furthermore, the welding machine of the present invention is characterized in that the irradiation unit is positioned above the imaging unit.

[0010] Furthermore, the welding machine of the present invention is characterized in that the irradiation unit irradiates the workpiece with a line laser that extends along the width direction.

[0011] Furthermore, the welding machine of the present invention comprises a support body configured to support the irradiation unit, the imaging unit, the welding unit, and the drive unit; a front wheel disposed on the front side of the bottom of the support body; a rear wheel disposed on the rear side of the bottom of the support body; and a fixing part disposed between the front wheel and the rear wheel at the bottom of the support body. The welding machine is movable on the upper surface of the work surface by the rotation of the front wheel and the rear wheel, and the position of the support body on the upper surface of the work surface is fixed by lifting the front wheel or the rear wheel off the work surface and fixing the fixing part to the work surface.

[0012] In the welding machine of the present invention, the irradiation unit is fixed to the drive unit.

[0013] The welding machine of the present invention is characterized in that the irradiation unit is housed in a housing, the housing has a first side surface which is the surface through which the light ray irradiated from the irradiation unit passes, the welding unit is disposed on the side of the first side surface of the housing, the first side surface is disposed so as to face the direction of the welding location when the light ray is irradiated from the irradiation unit toward the workpiece, and is disposed so as to face the side of the welding location when welding the welding location.

[0014] The welding machine of the present invention is characterized in that the drive unit has a plurality of arm sections, and the irradiation section is attached to the arm sections.

[0015] In the welding machine of the present invention, the irradiation unit is attached to the arm unit which constitutes the tip of the drive unit.

[0016] The welding machine of the present invention is characterized in that the irradiation unit has a light-emitting unit and a covering unit, and the covering unit is in a state where it does not cover the light-emitting unit while the light-emitting unit is irradiating the light beam, and covers the light-emitting unit while the welding work is being performed.

[0017] The welding machine of the present invention further comprises a support body configured to support the imaging unit and the drive unit, wherein the imaging unit is supported by the support body and is disposed on the side of the drive unit.

[0018] In the welding machine of the present invention, a transparent member and a blower are arranged in front of the imaging unit, and while the welding work is being performed, the blower blows gas in front of the transparent member as described above.

[0019] Furthermore, the present invention is a welding method for performing welding work on a welding location of a workpiece, comprising the steps of: moving a welding machine to the vicinity of the welding location; fixing the position of the welding machine on the work surface; irradiating the workpiece with a light ray; forming an image by photographing the part of the workpiece irradiated with the light ray, calculating the distance between the workpiece and the welding machine based on the image; and performing welding on the welding location.

[0020] The welding machine of the present invention is a welding machine that performs welding work on a welding location on a workpiece, and comprises an irradiation unit, an imaging unit, a welding unit, a drive unit, and a calculation control unit, wherein the irradiation unit is configured to irradiate the workpiece with a light ray, the imaging unit is configured to photograph the workpiece, the welding unit is configured to perform welding on the workpiece, the drive unit is configured to change the three-dimensional position and orientation of the welding unit, the calculation control unit irradiates the workpiece with a predetermined light ray from the irradiation unit, forms an image by photographing the workpiece with the imaging unit while the light ray is irradiated, calculates the positional relationship between the welding unit and the workpiece based on the image, and drives the welding unit with the drive unit to bring the tip of the welding unit closer to the workpiece and perform welding work.According to the welding machine of the present invention, the positional relationship between the welding unit and the workpiece is calculated based on an image taken while the light ray is irradiated, the welding unit is displaced to the precise position of the workpiece by the drive unit, and welding work can be performed on the workpiece by the welding unit.

[0021] Furthermore, the welding machine of the present invention is characterized in that the irradiation unit is positioned above the imaging unit. According to the welding machine of the present invention, by positioning the irradiation unit above, the light beam can be irradiated towards the workpiece without interference from the welding unit, drive unit, etc.

[0022] Furthermore, the welding machine of the present invention is characterized in that the irradiation unit irradiates the workpiece with a line laser that extends along the width direction. According to the welding machine of the present invention, by irradiating the workpiece with a line laser, the distance between the welding site and the welding machine can be accurately measured.

[0023] Furthermore, the welding machine of the present invention comprises a support body configured to support the irradiation unit, the imaging unit, the welding unit, and the drive unit; a front wheel disposed on the front side of the bottom of the support body; a rear wheel disposed on the rear side of the bottom of the support body; and a fixing part disposed between the front wheel and the rear wheel at the bottom of the support body. The welding machine is movable on the upper surface of the work surface by the rotation of the front wheel and the rear wheel, and the position of the support body on the upper surface of the work surface is fixed by lifting the front wheel or the rear wheel off the work surface and fixing the fixing part to the work surface. According to the welding machine of the present invention, by providing a front wheel and a rear wheel, the operator can move the support body on the upper surface of the work surface. Furthermore, once the support body has moved to the vicinity of the welding location, the position of the support body can be firmly fixed by lifting the front wheel or the rear wheel off the work surface and fixing the fixing part to the work surface.

[0024] In the welding machine of the present invention, the irradiation unit is fixed to the drive unit. According to the welding machine of the present invention, a dedicated member for arranging the irradiation unit on the upper side can be eliminated, and the configuration of the welding machine can be simplified. Furthermore, since the position and orientation of the drive unit can be precisely controlled by the calculation control unit, the position and orientation of the irradiation unit can also be precisely controlled, and the position of the welding site can be accurately measured.

[0025] In the welding machine of the present invention, the irradiation unit is housed in a housing, the housing has a first side surface which is the surface through which the light beam irradiated from the irradiation unit passes, the welding unit is disposed on the side of the first side surface of the housing, the first side surface is disposed so as to face the direction of the welding location when the light beam is irradiated from the irradiation unit toward the workpiece, and is disposed so as to face the side of the welding location when welding the welding location. According to the welding machine of the present invention, when irradiating a light beam from the irradiation unit toward the workpiece to identify the position of the welding location, it is possible to suppress obstruction of the irradiation of the light beam by the driving unit of the welding unit or the part supporting the welding unit.

[0026] The welding machine of the present invention is characterized in that the drive unit has a plurality of arm sections, and the irradiation section is attached to the arm sections. According to the welding machine of the present invention, by attaching the irradiation section to the arm sections, a mechanism to support the irradiation section can be eliminated, and the overall configuration of the welding machine can be simplified.

[0027] In the welding machine of the present invention, the irradiation unit is attached to the arm portion that constitutes the tip of the drive unit. According to the welding machine of the present invention, a beam of light can be irradiated from the irradiation unit onto the workpiece at a predetermined angle.

[0028] The welding machine of the present invention is characterized in that the irradiation unit has a light-emitting unit and a covering unit, and the covering unit is in a state where it does not cover the light-emitting unit while the light-emitting unit is irradiating the light beam, and covers the light-emitting unit while the welding work is being performed.According to the welding machine of the present invention, it is possible to suppress dust and other particles generated during welding from adhering to the light-emitting unit.

[0029] The welding machine of the present invention further comprises a support body configured to support the imaging unit and the drive unit, wherein the imaging unit is supported by the support body and is disposed on the side of the drive unit. According to the welding machine of the present invention, when the imaging unit is imaging a workpiece, the drive unit does not obstruct the imaging.

[0030] In the welding machine of the present invention, a transparent member and a blower are arranged in front of the imaging unit, and while the welding operation is being performed, the blower blows gas in front of the transparent member as described above. According to the welding machine of the present invention, it is possible to suppress dust and other particles generated during welding from adhering to the transparent member.

[0031] Furthermore, the present invention is a welding method for performing welding work on a welding location of a workpiece, comprising the steps of: moving a welding machine to the vicinity of the welding location; fixing the position of the welding machine on the work surface; irradiating the workpiece with a light ray; forming an image by photographing the part of the workpiece irradiated with the light ray; calculating the distance between the workpiece and the welding machine based on the image; and performing welding on the welding location. According to the welding method of the present invention, the positional relationship between the welding area and the workpiece is calculated based on an image taken while the light ray is irradiated, the welding area is displaced to the precise position of the workpiece by a drive unit, and the welding work is performed on the workpiece by the welding area.

[0032] This is a perspective view showing the entire welding machine according to the first embodiment of the present invention. This is a side view showing the entire welding machine according to the first embodiment of the present invention. This is a flowchart showing the welding method according to the first embodiment of the present invention. This is a perspective view showing the workpiece to be welded in the first embodiment of the present invention. This is a side view showing the step of moving the welding machine in the first embodiment of the present invention. This is a side view showing the step of fixing the welding machine in the first embodiment of the present invention. This is a perspective view showing the step of photographing the vicinity of the welding location in the first embodiment of the present invention. This is a diagram showing an example of a photographed image in the first embodiment of the present invention. This is a top view showing the welding step in the first embodiment of the present invention. This is a perspective view showing the entire welding machine according to the second embodiment of the present invention. This is a side view showing the entire welding machine according to the second embodiment of the present invention. This is a front view showing the entire welding machine according to the second embodiment of the present invention. This is a perspective view showing the welding method according to the second embodiment of the present invention. This is a side view showing the welding machine according to the third embodiment of the present invention. This is a front view showing the welding machine according to the third embodiment of the present invention. This is a perspective view showing the welding machine according to the third embodiment of the present invention. This is a perspective view showing the welding section and irradiation section of the welding machine according to the third embodiment of the present invention. This is a perspective view showing the photographic section of the welding machine according to the third embodiment of the present invention. This is a perspective view showing the imaging unit of a welding machine according to the third embodiment of the present invention. This is a side view showing the imaging unit and the like of a welding machine according to the third embodiment of the present invention. This is a perspective view showing a welding method

[0033] Hereinafter, a welding machine 10 and a welding method using the same according to an embodiment of the present invention will be described in detail with reference to the drawings. In the following description, the same reference numerals will be used for the same components in principle, and repeated descriptions will be omitted. In the following embodiments, the descriptions will be made using the directions of up, down, front, back, left, and right. Here, "front" refers to the direction in which the workpiece 22, which will be described later, is positioned relative to the welding machine 10. Also, "left and right" refers to the left and right when viewing the welding machine 10 from the front.

[0034] Figure 1A is a perspective view showing the entire welding machine 10. Figure 1B is a side view showing the entire welding machine 10.

[0035] The welding machine 10 is a device that performs welding work on the welding points 23 of the workpiece 22, which will be described later. Specifically, the welding machine 10 has an irradiation unit 11, an imaging unit 12, a welding unit 13, a drive unit 14, and a calculation control unit 15. The welding machine 10 also has a support 18, an operating unit 24, a gripping unit 25, a cylindrical support unit 27, etc.

[0036] The support 18 is a member that mechanically supports various components included in the welding machine 10, such as the irradiation unit 11, the imaging unit 12, the welding unit 13, and the drive unit 14. The support 18 has a first support part 181 and a second support part 182. The first support part 181 is a substantially plate-shaped member. The drive unit 14 is disposed in the front part of the first support part 181. The first housing part 29 is disposed in the rear part of the first support part 181. The second support part 182 is a member that extends upward in a substantially rod shape from the approximate center of the first support part 181. The second housing part 30 is disposed at the upper end of the second support part 182. The irradiation unit 11 is housed in the second housing part 30. An opening is formed on the front surface of the second housing part 30 for the light beam 16 emitted from the irradiation unit 11 to pass through.

[0037] The first housing 29 houses various electrical components that make up the welding machine 10, such as the calculation and control unit 15. The first housing 29 also houses the imaging unit 12. An opening is formed on the front of the first housing 29 for the imaging unit 12 to take images.

[0038] The irradiation unit 11 is configured to irradiate the workpiece 22 with a light ray 16, which will be described later. The irradiation unit 11 is a light-emitting element such as an LED, and irradiates the line laser 161, which is the light ray 16, towards the front and downward. The irradiation unit 11 is positioned above the imaging unit 12, which will be described later. As will be described later, the irradiation unit 11 irradiates the workpiece 22 with a line laser 161 that extends along the width direction.

[0039] The imaging unit 12 is configured to photograph the workpiece 22 and is a wide-angle camera capable of taking wide-angle shots in the left-right direction, for example. As will be described later, the imaging unit 12 photographs the portion of the workpiece 22 that is being irradiated by the line laser 161 from the irradiation unit 11.

[0040] The welding unit 13 is fixed to the tip of the drive unit 14 and is a device configured to perform welding work on the workpiece 22. The welding unit 13 is configured, for example, to perform gas welding on the workpiece 22. The welding unit 13 supplies a burning gas while bringing a welding rod into contact with the welding location 23 of the workpiece 22, which will be described later. The welding unit 13 may be configured to perform arc welding, electron beam welding, or laser welding.

[0041] The drive unit 14 is configured to change the three-dimensional position and orientation of the welded part 13. The drive unit 14 is also a multi-joint robot positioned between the workpiece 22 and the imaging unit 12. Specifically, the drive unit 14 has, from bottom to top, a base 141, a first joint 142, a support 143, a second joint 144, a first arm 145, a third joint 146, and a second arm 147. The base 141 is fixed to the front upper part of the first support 181 and mechanically supports the other parts of the drive unit 14. The first joint 142 is a joint that allows the support 143 to rotate relative to the base 141 along an axis extending in the vertical direction. The support 143 is the part that supports the first arm 145 via the second joint 144. The second joint 144 is a part that rotatably connects the support part 143 and the first arm part 145 with a rotation axis extending horizontally as the center of rotation. The third joint 146 is a part that rotatably connects the first arm part 145 and the second arm part 147 with a rotation axis extending horizontally as the center of rotation. Each joint is equipped with a motor, and the operation of each motor is controlled by the calculation control unit 15.

[0042] The arithmetic control unit 15 consists of semiconductor elements such as a CPU (Central Processing Unit). The arithmetic control unit 15 may also include semiconductor memory devices such as RAM (Random Access Memory) and ROM (Read Only Memory) as storage units. Such storage units store programs, parameters, etc. Based on the programs, parameters, etc. read from the storage units, the arithmetic control unit 15 executes the functions and methods described later.

[0043] The operating unit 24 is, for example, a part having an instruction function, which includes a push-type button located on the upper surface of the operating unit 24. The operating unit 24 is connected to the calculation control unit 15, etc., via a harness (not shown).

[0044] The gripping part 25 is attached to the upper end of the irradiation part 11 and is a part that allows an operator to grip it. The gripping part 25 is made of, for example, a steel bar bent and formed into a substantially rectangular shape. By gripping the gripping part 25, the operator can move the welding machine 10 on the upper surface of the work surface while rotating the front wheels 19 and the rear wheels 20 described later.

[0045] The cylindrical support part 27 is a pipe-shaped member extending rearward from the rear end of the welding part 13. Inside the cylindrical support part 27, an intermediate part such as a hose for supplying gas to the welding part 13 and a welding rod is inserted.

[0046] The suspension support part 26 is suspended from the second housing part 30 and is a member that pulls the intermediate part of the cylindrical support part 27 from above. By pulling up the intermediate part of the cylindrical support part 27 by the suspension support part 26, the cylindrical support part 27 can be held more firmly.

[0047] As will be described later, the arithmetic control unit 15 irradiates a predetermined light beam 16 from the irradiation part 11 onto the workpiece 22, and forms an image 17 by photographing the workpiece 22 in a state where the light beam 16 is irradiated, using the photographing part 12. Further, the arithmetic control unit 15 calculates the positional relationship between the welding part 13 and the workpiece 22 based on the image 17, and drives the welding part 13 by the drive part 14. Thereby, the tip of the welding part 13 is configured to approach the workpiece 22 and execute a welding operation.

[0048] Referring to FIG. 1B, the welding machine 10 has front wheels 19, rear wheels 20, a fixing part 21, and a pedal 28 as mechanisms for controlling movement and fixation.

[0049] The front wheels 19 are wheels disposed on the front side at the bottom of the support 18. A plurality of front wheels 19 are arranged along the left - right direction.

[0050] The rear wheels 20 are wheels disposed on the rear side at the bottom of the support 18. One rear wheel 20 may be arranged, or a plurality of rear wheels 20 may be arranged along the left - right direction.

[0051] The welding machine 10 is movable on the upper surface of the work surface by the rotation of its front wheels 19 and rear wheels 20. When moving the welding machine 10 on the upper surface of the work surface, the operator holds the gripping part 25 and applies pressure in the desired direction. In this way, the front wheels 19 and rear wheels 20 rotate, and the welding machine 10 moves.

[0052] The fixing part 21 is a fixing means positioned at the bottom of the support 18 between the front wheel 19 and the rear wheel 20. The fixing part 21 is, for example, an electromagnet. When the fixing part 21 is in the OFF state, it does not exert any fixing force. On the other hand, when the fixing part 21 is in the ON state, it is attracted to the iron plate which is the work surface on which the welding machine 10 moves. Therefore, the welding machine 10 can be firmly fixed to the work surface by the fixing part 21.

[0053] The pedal 28 is positioned at the rear end of the first support portion 181 and is connected to the rear wheel 20 via a linkage mechanism or the like. When the pedal 28 is tilted upward toward the rear, the rear wheel 20 is pushed down and in contact with the upper surface of the work surface. On the other hand, when the pedal 28 is pushed down by the operator, the pedal 28 tilts downward toward the rear, and the rear wheel 20 rises and moves away from the work surface.

[0054] Referring to Figures 2 and subsequent figures, a welding method using the welding machine 10 having the above-described configuration will be explained.

[0055] Figure 2 is a flowchart showing the welding method.

[0056] The welding method according to the first embodiment performs welding work on a welding location 23 of a workpiece 22. Specifically, the welding method according to the first embodiment comprises the steps of: moving the welding machine 10 to the vicinity of the welding location 23; fixing the position of the welding machine 10 on the work surface; irradiating the workpiece 22 with a light ray 16 in the step S12; forming an image 17 by photographing the part of the workpiece 22 irradiated with the light ray 16, and calculating the distance between the workpiece 22 and the welding machine 10 based on the image 17; and performing welding on the welding location 23 in the step S14.

[0057] In step S10, the operator moves the welding machine 10 to the vicinity of the welding location 23.

[0058] Figure 3 is a perspective view showing a workpiece 22 to be welded by a welding machine 10. The workpiece 22 has a first workpiece 221 and a second workpiece 222. The first workpiece 221 is a steel plate extending along a horizontal plane. The second workpiece 222 is a steel plate extending along a vertical plane. The welding location 23 is the part where the front edge of the fixing part 21 contacts the rear surface of the second workpiece 222. In the first embodiment, welding is performed at the welding location 23 to weld the front edge of the first workpiece 221 to the rear surface of the second workpiece 222. Here, the upper surface of the first workpiece 221 is the work surface 31. That is, the welding machine 10 described above is placed on the upper surface of the first workpiece 221 and moves along the upper surface of the first workpiece 221.

[0059] Step S10 will be described in detail with reference to Figures 4A and 4B. In Figures 4A and 4B, the work surface 31 is shown by a dotted line.

[0060] Figure 4A is a side view showing the welding machine 10 in step S10. When moving the welding machine 10, the pedal 28 is not pushed down. Therefore, the rear wheel 20 is positioned at the same height as the front wheel 19. The welding machine 10 is in contact with the work surface 31, which is the first workpiece 221, via the front wheel 19 and the rear wheel 20. Therefore, when the operator grasps the gripping part 25 and tries to move the welding machine 10, the front wheel 19 and the rear wheel 20 rotate, allowing the welding machine 10 to move freely on the work surface 31. Here, the operator moves the welding machine 10 to the immediate vicinity of the welding location 23 mentioned above.

[0061] In step S10, since the front wheel 19 and rear wheel 20 are in contact with the first workpiece 221, the fixing part 21 is not in contact with the first workpiece 221. Also, since the fixing part 21, which is an electromagnet, is in the OFF state, the fixing part 21 is not attracted to the first workpiece 221.

[0062] In step S11, once the welding machine 10 has reached the vicinity of the welding location 23, the operator fixes the position of the welding machine 10 on the work surface 31. Specifically, referring to Figure 4B, the operator pushes the pedal 28 downward. This causes the rear wheel 20 to rise. As mentioned above, the support 18 is supported by the front wheel 19 and the rear wheel 20. Also, a fixing part 21 is provided on the bottom surface of the support 18 between the front wheel 19 and the rear wheel 20. Therefore, when the rear wheel 20 rises by pushing down the pedal 28, the fixing part 21 comes into contact with the work surface 31. That is, the support 18 is supported by the front wheel 19 and the fixing part 21. In this state, the fixing part 21, which is an electromagnet, is turned ON. When this is done, the fixing part 21 is attracted to the work surface 31, which is, for example, a steel plate. This fixes the position of the welding machine 10 on the work surface 31.

[0063] In step S12, the calculation control unit 15 irradiates the workpiece 22 with the line laser 161, which is the light beam 16.

[0064] Figure 5A is a perspective view showing the welding machine 10 in a state where the second workpiece 222 is being photographed while the line laser 161 is being irradiated. Figure 5B is a diagram showing an example of an image taken by the imaging unit 12. In Figures 5A and 5B, the line laser 161 is shown as a dashed line.

[0065] Referring to Figure 5A, the welding machine 10 is sufficiently close to the welding location 23 as a result of the steps described above. Also, the longitudinal direction of the support 18 is approximately perpendicular to the welding location 23.

[0066] In this step, based on instructions from the calculation control unit 15, the irradiation unit 11 irradiates the second workpiece 222 with a line laser 161 through an opening (not shown) formed on the front of the operation unit 24. The line laser 161 is irradiated onto the rear surface of the second workpiece 222 so as to be approximately parallel to the horizontal plane or the welding area 23. Based on instructions from the calculation control unit 15, the imaging unit 12 takes a photograph of the rear surface of the second workpiece 222 while the line laser 161 is irradiated. Since the imaging unit 12 is a wide-angle camera that can take wide-angle shots along the left-right direction, it can also photograph the left and right sides of the drive unit 14. For example, the imaging unit 12 can also photograph from the right end to the left end of the welding area 23. As mentioned above, since the imaging unit 12 is located behind the drive unit 14, the drive unit 14 is reflected in the center of the image taken by the imaging unit 12.

[0067] Figure 5B shows an image 17 captured by the aforementioned imaging unit 12. Image 17 has a first image section 171 and a second image section 172. The first image section 171 is the portion of image 17 that shows the workpiece 22 being illuminated by the light ray 16. The second image section 172 is the portion of image 17 in which the workpiece 22 is shielded by the drive unit 14. Here, the second image section 172 is located in the central part in the left-right direction. The first image section 171 is located in the left and right portions in the left-right direction.

[0068] The arithmetic control unit 15 estimates the position where the light ray 16 is irradiated in the second image unit 172 from the first image unit 171. Specifically, as described above, the second image unit 172 is arranged between the first image units 171. Therefore, the arithmetic control unit 15 can easily interpolate and estimate the position in the second image unit 172 from the position of the line laser 161 in the left first image unit 171 and the position of the line laser 161 in the right first image unit 171. In Figure 5B, the line laser 161 estimated in the second image unit 172 is shown and enclosed by a dotted line.

[0069] In step S13, the calculation control unit 15 calculates the distance between the welding location 23 and the welding machine 10.

[0070] Specifically, referring to Figure 5A, the vertical position of the irradiation unit 11 is known. The tilt angle at which the irradiation unit 11 irradiates the line laser 161 downwards from the horizontal is also known. Furthermore, the positional relationship between the irradiation unit 11 and each part of the drive unit 14 is also known. From this, referring to Figure 5B, if the distance L10 between the welding location 23 and the line laser 161 is determined, the distance in the front-rear direction between each part of the welding machine 10, for example, the drive unit 14 and the welding location 23, can be calculated using geometric theorems such as the Pythagorean theorem. The positional relationship between each part of the welding machine 10 and the welding location 23 in the vertical direction can also be calculated. If the relative positional relationship between the center of the base part 141 of the drive unit 14 and the welding location 23 is determined in each direction (up, down, front, back, left, and right), accurate welding can be performed on the welding location 23 while moving the tip of the welding unit 13 left and right and backward along the vicinity of the welding location 23.

[0071] In step S14, the calculation control unit 15 performs welding on the welding location 23.

[0072] Figure 6 is a top view showing a welding machine 10 performing welding work on a welding location 23. Specifically, the calculation and control unit 15 brings the tip of the welding part 13 close to the left end of the welding location 23, and performs welding by bringing the welding rod into contact with it while emitting gas. The calculation and control unit 15 also performs welding while moving the welding part 13 to the right along the welding location 23. When the welding part 13 has moved to the right end of the welding location 23, the calculation and control unit 15 terminates the welding.

[0073] In step S15, the operator moves the welding machine 10 to the next location where welding will be performed.

[0074] Specifically, referring to Figure 4B, the operator flicks the pedal 28 upward. This causes the rear wheel 20 to move downward and make contact with the work surface 31. Furthermore, the calculation control unit 15 releases the fixing part 21 from its suction to the work surface 31 by turning the fixing part 21 to the OFF state. As a result, as shown in Figure 4A, the operator can move the welding machine 10 to the next welding location.

[0075] In particular, when the welding machine 10 is used in a shipyard, there are many welding locations 23 as shown in Figure 3. On the other hand, the welding machine 10 according to the first embodiment can be easily fixed and moved by operating the pedal 28, and furthermore, positioning can be easily performed by irradiating with a line laser 161 from the irradiation unit 11. Therefore, by using the welding machine 10 in a shipyard, welding work can be simplified and accelerated.

[0076] Referring to Figures 7 and subsequent figures, the configuration of the welding machine 10 according to the second embodiment and the welding method using it will be described. The configuration of the welding machine 10 and the welding method in the second embodiment are substantially the same as those in the first embodiment. Therefore, the following description will focus on the differences between the second embodiment and the first embodiment, omitting and referencing the descriptions of similar parts.

[0077] Figure 7 is a perspective view showing the welding machine 10 according to the second embodiment, Figure 8A is a side view showing the welding machine 10 according to the second embodiment, and Figure 8B is a front view showing the welding machine 10 according to the second embodiment. Figure 7 shows the configuration of the welding machine 10 when it is moving and when it is measuring length.

[0078] Referring to Figures 7 to 8B, the welding machine 10 has a drive unit 14. As described above, the drive unit 14 changes the three-dimensional position and orientation of the welding part 13. The drive unit 14 also has a base portion 141 to a second arm portion 147, as described above. Furthermore, the tip side of the drive unit 14 may be provided with additional arm portions and joint portions. The welding part 13 and the cylindrical support portion 27 are fixed to the tip of the drive unit 14.

[0079] In the second embodiment, the second housing portion 30 and the illumination unit 11 housed therein are fixed to an intermediate portion of the drive unit 14. Here, the second housing portion 30 is fixed to the upper end of the first arm portion 145. The second housing portion 30 is also fixed to the upper end of the first arm portion 145 via a plate-shaped connecting member. By fixing the second housing portion 30 to the first arm portion 145, a dedicated member for positioning the second housing portion 30 and the illumination unit 11 upwards is unnecessary, and the second housing portion 30 can be positioned upwards. The illumination unit 11 is positioned on the front-facing surface of the second housing portion 30 during movement and length measurement. The second housing portion 30 also has a first side surface 301 that faces forward in the state shown in Figure 7. The illumination unit 11 faces the outside through an opening formed by opening the lower end of the first side surface 301. Furthermore, a light ray 16, described later, is emitted from the irradiation unit 11 to the outside through the opening.

[0080] The imaging unit 12 is positioned below the drive unit 14. Specifically, the drive unit 14 has a base portion 141 at its lower end that supports the entire drive unit 14, and the imaging unit 12 is built into the base portion 141. Therefore, since the imaging unit 12 is positioned at the front end of the welding machine 10, other components of the welding machine 10 do not obstruct the field of view of the imaging unit 12. As a result, as will be described later, the imaging unit 12 can capture the light rays 16 irradiated onto the workpiece 22 without being affected by obstacles.

[0081] The imaging unit 12 is configured to photograph the front side of the welding machine 10 through an opening formed on the front surface of the base unit 141. This opening is covered by a sliding cover, which is opened only when taking pictures and closed when moving or welding. This prevents dust and other particles from affecting the imaging unit 12 during movement and welding.

[0082] Referring to Figure 9, step S13 described above, that is, the length measurement step of calculating the distance between the welding location 23 and the welding machine 10, will now be explained.

[0083] Here, the welding machine 10 is positioned such that the first side surface 301, which is the surface that the irradiation unit 11 faces from the second housing 30, faces the second workpiece 222. In other words, in this step, the first side surface 301 faces forward.

[0084] Furthermore, the welded portion 13 and the cylindrical support portion 27 are located on the right side, which is the side of the second housing portion 30. Therefore, the welded portion 13 and the cylindrical support portion 27 do not obstruct the light rays 16 emitted from the irradiation portion 11.

[0085] In this state, based on instructions from the calculation control unit 15, a light ray 16 is irradiated from the irradiation unit 11 toward the second workpiece 222. The light ray 16 may be a line laser 161, or it may be a laser that forms multiple irradiation points (for example, two) along the left-right direction and parallel to the horizontal direction at a predetermined location.

[0086] The imaging unit 12 generates an image by taking wide-angle photographs of the second workpiece 222 and the welding area 23 in the left-right direction, where the light ray 16 is irradiated. There are no components of the welding machine 10 in front of the imaging unit 12. Therefore, there are no obstacles in the field of view of the imaging unit 12 that would obstruct the imaging of the workpiece 22 and the welding area 23. As a result, the imaging unit 12 can take good photographs of the second workpiece 222 and the welding area 23 in the area where the light ray 16 is irradiated.

[0087] The calculation control unit 15 calculates the distance L10 between the portion of the workpiece 22 illuminated by the light ray 16 and the welding location 23 from the generated image, similar to the first embodiment described above. Since the angle of inclination of the direction of illumination of the light ray 16 from the horizontal plane, the height of the illumination unit 11, etc., are known, if the distance L10 can be measured, the distance between the reference position for operating the drive unit 14 and the welding unit 13 and the welding location 23 can be calculated using geometric theorems such as the Pythagorean theorem and trigonometric functions.

[0088] Referring to Figure 10, step S14, that is, the method of welding the welding location 23, will be explained. Here, the calculation control unit 15 rotates the first joint 142 approximately 90 degrees clockwise when viewed from above. In this way, the welding part 13 is positioned on the front side of the support 18. Also, the first side surface 301 of the second housing 30 faces to the left. The calculation control unit 15 moves the welding part 13 with the drive unit 14, thereby performing welding from the left end to the right end of the welding location 23. Through this welding, the front edge of the first workpiece 221 and the rear surface of the second workpiece 222 are welded together.

[0089] Referring to Figures 11A and later, the configuration of the welding machine 10 and the welding method according to the third embodiment will be described. The configuration of the welding machine 10 and the welding method according to the third embodiment are, in principle, the same as those of the first or second embodiment described above. Therefore, the following description will focus on the differences from the first or second embodiment. On the other hand, matters that are the same as those of the first or second embodiment will be omitted from the description, and the previously described explanations will be used as a reference.

[0090] The overall configuration of the welding machine 10 according to the third embodiment will be described with reference to Figures 11A to 12B. Figure 11A is a side view of the welding machine 10. Figure 11B is a front view of the welding machine 10. Figure 12A is a perspective view of the welding machine 10. Figure 12B is a perspective view of the welding machine 10 from a different viewpoint.

[0091] The welding machine 10 is a robot that performs welding work semi-automatically based on the operator's instructions for transport, positioning, and starting. The welding machine 10 mainly consists of a support body 18, a drive unit 14, an irradiation unit 11, and a welding unit 13. The operation of the welding machine 10 is controlled by the aforementioned calculation control unit 15.

[0092] The support 18 is a roughly plate-shaped member, and is made of, for example, an iron plate with sufficient rigidity to support the drive unit 14. The drive unit 14 and the imaging unit 12 are arranged on the upper surface of the support 18. The fixing unit 21 is arranged on the lower surface of the support 18. Here, the imaging unit 12 is arranged to the side of the drive unit 14. In other words, the drive unit 14 and the like are not arranged in front of the imaging unit 12. That is, the drive unit 14 is not arranged between the welding target area (described later) and the imaging unit 12. In this way, when the imaging unit 12 is imaging the workpiece 22, the drive unit 14 does not obstruct the imaging.

[0093] The drive unit 14 has, from bottom to top, a base portion 141, a first joint portion 142, a first arm portion 145, a second joint portion 144, a second arm portion 147, a third joint portion 146, a third arm portion 148, a fourth joint portion 149, and a fourth arm portion 1410. The drive unit 14 is a so-called articulated robot. By rotating each arm portion at each joint portion, the drive unit 14 can adjust the position and orientation of the irradiation portion 11 and the welding portion 13 to a position suitable for welding.

[0094] The base portion 141 is the lowest part of the drive unit 14 and is fixed to the upper surface of the support 18. The drive unit 14 extends in a roughly columnar shape in the vertical direction, and its upper end portion is bent at roughly a right angle toward the left.

[0095] The first joint 142 is a part that rotatably connects the base 141 and the first arm 145. At the first joint 142, the first arm 145 can rotate around an axis extending in the left-right direction as its center of rotation. The first arm 145 is rotationally driven by a motor (not shown) located near the first joint 142. The same applies to the other joints.

[0096] The lower end of the first arm portion 145 is connected to the base portion 141 via the first joint portion 142, and the upper end is connected to the second arm portion 147 via the second joint portion 144. The middle portion of the first arm portion 145 extends in a substantially straight line, and both ends are bent at substantially right angles to the middle portion.

[0097] The second joint 144 is a joint that rotatably connects the first arm 145 and the second arm 147. At the second joint 144, the second arm 147 is rotatable relative to the first arm 145. At the second joint 144, the rear end of the second arm 147 rotates around an axis extending in the left-right direction as the center of rotation.

[0098] The second arm portion 147 has an intermediate portion that extends in a substantially straight line along the front-rear direction, its rear end is bent at a substantially right angle, and its front end is also bent at a substantially right angle.

[0099] The third joint 146 is a joint that rotatably connects the front end of the second arm 147 and the upper end of the third arm 148. The upper end of the third arm 148 is rotatable about an axis extending in the left-right direction within the third arm 148 as the center of rotation.

[0100] The third arm portion 148 is an arm portion whose upper end extends in the left-right direction and whose lower end extends in the up-down direction.

[0101] The fourth joint 149 is a joint that rotatably connects the lower end of the third arm 148 and the rear end of the fourth arm 1410. In the fourth joint 149, the fourth arm 1410 is rotatable around an axis extending in the vertical direction as its center of rotation.

[0102] The fourth arm portion 1410 is an arm that extends in a substantially columnar shape along the front-rear direction. The irradiation portion 11 and the welding portion 13 are arranged at the front end of the fourth arm portion 1410. The irradiation portion 11 is fixed to the tip of the fourth arm portion 1410 via a mounting portion 34. By attaching the irradiation portion 11 to the arm portion, a support mechanism for supporting the irradiation portion 11 can be eliminated, simplifying the overall configuration of the welding machine 10. Furthermore, the irradiation portion 11 is attached to the fourth arm portion 1410 which constitutes the tip of the drive portion 14. Therefore, a beam of light 16 can be irradiated from the irradiation portion 11 onto the workpiece 22 at a predetermined angle.

[0103] Referring to Figure 11A, a joint can also be provided in the middle of the base portion 141 in the vertical direction. This joint allows the upper portion of the base portion 141 to rotate relative to the lower portion. With this configuration, the upper portion of the base portion 141 can be rotated with an axis extending in the vertical direction as the axis of rotation.

[0104] A protective part 35, made of a metal plate having a roughly rectangular parallelepiped shape, is fixed to the front end of the fourth arm portion 1410. The front surface of the protective part 35 is an opening. The irradiation unit 11 and the like, which will be described later, are housed inside the protective part 35.

[0105] The configuration of the irradiation unit 11 and the welding unit 13 will be described with reference to Figure 13A. Figure 13A is a perspective view showing the configuration of the irradiation unit 11 and the welding unit 13 during welding. Figure 13B is a perspective view showing the configuration of the irradiation unit 11 and the welding unit 13 when the laser is irradiated.

[0106] Referring to Figure 13A, the irradiation unit 11 and the welding unit 13 are attached to the front end of the fourth arm unit 1410. The light-emitting unit 111 is attached to the tip of the fourth arm unit 1410 via a mounting fixture. The light-emitting unit 111 is located inside the cylindrical unit 113 and is therefore not shown in the drawing. As mentioned above, the light-emitting unit 111 is, for example, an LED. The cylindrical unit 113 is a substantially cylindrical member with an open front end.

[0107] The covering portion 112 is a substantially lid-shaped member that covers the front end opening of the cylindrical portion 113. The covering portion 112 is rotatably attached to the upper end of the tip of the cylindrical portion 113. The upper end of the covering portion 112 is rotatable with respect to an axis extending in the left-right direction. The covering portion 112 covers the light-emitting portion 111 while welding is being performed. In this way, even if dust and other particles generated during welding are scattered toward the light-emitting portion 111, the progress of the dust is blocked by the covering portion 112, thereby suppressing the adhesion of dust and other particles to the light-emitting portion 111.

[0108] Referring to Figure 13B, the covering portion 112 is kept uncovered from the light-emitting portion 111 while the light-emitting portion 111 is irradiating the light ray 16. Specifically, the covering portion 112 rotates upward with its upper end as the pivot point. In this way, the front end opening of the cylindrical portion 113 is not covered by the covering portion 112, so the line laser irradiated from the light-emitting portion 111 is irradiated forward from the front end of the cylindrical portion 113.

[0109] Figure 14A is a perspective view of the imaging unit 12 from above. Figure 14B is a perspective view of the imaging unit 12 from below. The configuration and operation of the imaging unit 12 will be explained with reference to Figures 14A and 14B.

[0110] Referring to Figures 14A and 14B, the imaging unit 12 mainly comprises a housing 36, a blower 33, a transparent member 32, and an imaging unit 38 and a lens 37, which will be described later. As mentioned above, the imaging unit 12 is a device that photographs the workpiece 22 being irradiated with a laser while the irradiation unit 11 is irradiating the workpiece 22 with a laser.

[0111] The housing portion 36 is a box-shaped member with a roughly rectangular parallelepiped shape, made of a metal plate or the like. The housing portion 36 has a longitudinal direction along the front-to-back direction.

[0112] The housing 36 houses a camera unit 12, which will be described later. A transparent member 32 and an air blower 33 are arranged in front of the camera unit 12.

[0113] The front of the housing 36 is open, and a transparent member 32 is fitted into this front opening. The transparent member 32 is made of a transparent material that transmits visible light, such as a glass plate.

[0114] The air blower 33 is configured to blow air downwards on the front side of the transparent member 32. Specifically, the air blower 33 is a pipe-shaped member that extends along the left-right direction on the front and upper side of the transparent member 32. As shown in Figure 14B, a ventilation hole is formed in the lower part of the air blower 33, penetrating the thick part of the air blower 33. Multiple such ventilation holes are formed along the left-right direction. The air blower 33 is connected to a compressor (not shown).

[0115] Referring to Figure 15, a lens 37 and an imaging unit 38 are arranged behind the transparent member 32. As previously mentioned, a blower unit 33 is arranged in front of and above the transparent member 32. The imaging unit 38 can perform wide-angle photography by capturing light focused or diffused by the lens 37. Due to wide-angle photography by the lens 37, a predetermined distortion occurs in the image captured by the imaging unit 38. Therefore, when calculating the relative positions of the irradiation unit 11 and the welding unit 13 from the image obtained by the imaging unit 38, the effect of distortion is removed from the image before performing predetermined image processing.

[0116] During welding, compressed air is supplied to the air blower 33 from a compressor (not shown), and the air is ejected downward from the vents of the air blower 33. This creates a so-called air curtain in front of the transparent member 32. As a result, even if dust is propagating toward the transparent member 32 during welding, its advance is blocked by the air curtain. Consequently, dust adhesion to the front surface of the transparent member 32 during welding can be suppressed. Therefore, clear images can be taken through the transparent member 32, and the positions of the irradiation unit 11 and the welding unit 13 can be detected with high accuracy from the images obtained from these images.

[0117] In the third embodiment, the alignment and welding method using the welding machine 10 is basically the same as that of the first and second embodiments described above.

[0118] Specifically, referring to Figure 16, first, the irradiation unit 11 and the workpiece 22 are aligned. Here, an example is given of welding two steel plate workpieces 22 together in a shipyard. Examples of workpieces 22 include the first workpiece 221, the second workpiece 222, the third workpiece 223, and the fourth workpiece 224. The first workpiece 221 is a steel plate with a main surface facing up and down. The second workpiece 222 is a steel plate with a main surface facing front and back. The third workpiece 223 is a steel plate with a main surface facing left and right. The fourth workpiece 224 is a steel plate with a main surface facing left and right.

[0119] The welding location 23 is where the welding machine 10 performs welding. The welding location 23 has a first welding location 231, a second welding location 232, and a third welding location 233. The first welding location 231 is where the front edge of the third workpiece 223 abuts against the rear main surface of the second workpiece 222. The second welding location 232 is where the front surface of the first workpiece 221 abuts against the rear main surface of the second workpiece 222. The third welding location 233 is where the front surface of the fourth workpiece 224 abuts against the rear main surface of the second workpiece 222. The lower end of the first welding location 231 and the right end of the second welding location 232 are continuous. The left end of the second welding location 232 and the lower end of the third welding location 233 are continuous.

[0120] First, the worker places the welding machine 10 on the top surface of the first workpiece 221. The welding machine 10 is positioned near the second welding location 232. The welding machine 10 is relatively lightweight, weighing, for example, about 15 kg. Therefore, even a female worker can easily move and transport the welding machine 10. Furthermore, because the welding machine 10 is compact and lightweight, one worker can perform welding work using multiple welding machines 10. Specifically, while one welding machine 10 is performing welding work, the other welding machine 10 can be transported and positioned. In this way, welding work can be performed efficiently.

[0121] Next, based on the operator's instructions, the welding machine 10 enters alignment mode. In alignment mode, the position and angle of the irradiation unit 11 are set to a predetermined value by the displacement of the drive unit 14. In this state, the operator moves the welding machine 10 along the front-rear direction. Specifically, the operator adjusts the position of the welding machine 10 in the front-rear direction so that the line laser 161 emitted by the welding machine 10 illuminates the second welding location 232 or its vicinity. Subsequently, based on the operator's instructions, the calculation control unit 15 operates the fixing unit 21, which is an electromagnet, and fixes the welding machine 10 to the upper surface of the first workpiece 221 by its magnetic force.

[0122] Referring to Figure 17, the welding machine 10 then scans the workpiece 22 with the line laser 161. Specifically, based on instructions from the calculation control unit 15, the welding machine 10 irradiates the workpiece 22 with the line laser 161 from the irradiation unit 11 towards the front and downward. At this time, the line laser 161 irradiates the left main surface of the third workpiece 223, the first welding location 231, the rear main surface of the second workpiece 222, the third welding location 233, and the right main surface of the fourth workpiece 224.

[0123] Furthermore, the calculation control unit 15 performs a scanning operation that moves the line laser 161 upward by displacing the drive unit 14.

[0124] The imaging unit 12 acquires image data by taking pictures at predetermined timings during the scanning operation. The imaging unit 12 photographs the left main surface of the third workpiece 223, the first welding location 231, the rear main surface of the second workpiece 222, the third welding location 233, and the right main surface of the fourth workpiece 224 while the line laser 161 is irradiating them. The imaging unit 12 also performs the photography each time the line laser 161 rises by a predetermined length (for example, 2 mm).

[0125] The calculation control unit 15 calculates the relative positions of the first welding location 231, the second welding location 232, and the third welding location 233 and the welding machine 10 from multiple image data captured during the scanning operation. As a method for this calculation, for example, a laser triangulation type three-dimensional shape measurement method may be employed.

[0126] Next, referring to Figure 18, the welding operation is performed by moving the front end of the welding section 13 of the welding machine 10 along the welding location 23, based on the instructions of the calculation control unit 15. For example, the welding operation is performed in the order of the first welding location 231, the second welding location 232, and the third welding location 233.

[0127] Once the welding work is completed, the worker moves the welding machine 10 to another location and continues welding work at that location.

[0128] Although embodiments of the present invention have been described above, the present invention is not limited thereto, and modifications are possible without departing from the spirit of the invention. Furthermore, the above-described embodiments can be combined with each other.

[0129] For example, as shown in Figures 4A and 4B, the welding machine 10 was moved and fixed by moving the rear wheels 20 in the vertical direction. However, it is also possible to move and fix the welding machine 10 by moving the front wheels 19 in the vertical direction.

[0130] Furthermore, during welding, the operator can set the movement speed of the welding area 13, the speed and acceleration of the welding start position, etc. These settings can also be made by the operator using the control unit 24 of the welding machine 10, or by using a portable electronic device such as a smartphone.

[0131] 10 Welding machine 11 Irradiation unit 111 Light-emitting unit 112 Covering unit 113 Cylindrical unit 12 Imaging unit 13 Welding unit 14 Drive unit 141 Base unit 142 First joint unit 143 Support unit 144 Second joint unit 145 First arm unit 146 Third joint unit 147 Second arm unit 148 Third arm unit 149 Fourth joint unit 1410 Fourth arm unit 15 Calculation control unit 16 Light beam 161 Line laser 17 Image 171 First image unit 172 Second image unit 18 Support body 181 First support unit 182 Second support unit 19 Front wheel 20 Rear wheel 21 Fixing unit 22 Workpiece 221 First workpiece 222 Second workpiece 223 Third workpiece 224 Fourth workpiece 23 Welding point 24 Operating part 25 Gripping part 26 Suspension support part 27 Cylindrical support part 28 Pedal 29 First housing part 30 Second housing part 301 First side surface 31 Working surface 32 Transparent member 33 Air blower part 34 Mounting part 35 Protective part 36 Housing part 37 Lens 38 Imaging part

Claims

1. A welding machine for performing welding work on a workpiece, comprising: an irradiation unit, an imaging unit, a welding unit, a drive unit, and a calculation control unit, wherein the irradiation unit is configured to irradiate the workpiece with a light ray, the imaging unit is configured to photograph the workpiece, the welding unit is configured to perform welding on the workpiece, the drive unit is configured to change the three-dimensional position and orientation of the welding unit, and the calculation control unit irradiates the workpiece with a predetermined light ray from the irradiation unit, forms an image by photographing the workpiece with the imaging unit while the light ray is irradiated, calculates the positional relationship between the welding unit and the workpiece based on the image, and drives the welding unit with the drive unit to bring the tip of the welding unit closer to the workpiece and perform the welding work.

2. The welding machine according to claim 1, characterized in that the irradiation unit is arranged above the imaging unit.

3. The welding machine according to claim 1, characterized in that the irradiation unit irradiates the workpiece with a line laser that extends along the width direction.

4. A welding machine according to claim 1, comprising: a support body configured to support the irradiation unit, the imaging unit, the welding unit and the drive unit; a front wheel disposed on the front side of the bottom of the support body; a rear wheel disposed on the rear side of the bottom of the support body; and a fixing part disposed between the front wheel and the rear wheel at the bottom of the support body, wherein the welding machine is movable on the upper surface of the work surface by the rotation of the front wheel and the rear wheel, and the position of the support body on the upper surface of the work surface is fixed by lifting the front wheel or the rear wheel off the work surface and fixing the fixing part to the work surface.

5. The welding machine according to claim 1, characterized in that the irradiation unit is fixed to the drive unit.

6. The welding machine according to claim 5, characterized in that the irradiation unit is housed in a housing, the housing has a first side surface which is the surface through which the light ray irradiated from the irradiation unit passes, the welding unit is disposed on the side of the first side surface of the housing, the first side surface is disposed so as to face the direction of the welding location when the light ray is irradiated from the irradiation unit toward the workpiece, and is disposed so as to face the side of the welding location when welding the welding location.

7. The welding machine according to claim 1, characterized in that the drive unit has a plurality of arm sections, and the irradiation section is attached to the arm sections.

8. The welding machine according to claim 7, characterized in that the irradiation unit is attached to the arm unit which constitutes the tip of the drive unit.

9. The welding machine according to claim 7, wherein the irradiation unit comprises a light-emitting unit and a covering unit, and the covering unit is configured not to cover the light-emitting unit while the light-emitting unit is irradiating the light beam, and to cover the light-emitting unit while the welding operation is being performed.

10. The welding machine according to claim 7, further comprising a support configured to support the imaging unit and the drive unit, wherein the imaging unit is supported by the support and is disposed on the side of the drive unit.

11. The welding machine according to claim 7, wherein a transparent member and a blower are arranged in front of the imaging unit, and while the welding work is being performed, the blower blows gas in front of the transparent member as described above.

12. A welding method for performing welding work on a welding location of a workpiece, comprising the steps of: moving a welding machine to the vicinity of the welding location; fixing the position of the welding machine on the work surface; irradiating the workpiece with a light ray; forming an image by photographing the part of the workpiece irradiated with the light ray, and calculating the distance between the workpiece and the welding machine based on the image; and performing welding on the welding location.

Images