Welding positioning device and welding positioning method

Abstract

To enable facilitation of preparation work in teaching work.SOLUTION: A welding positioning device is a positioning device of a welding robot having a function of positioning an electrode bar mounted to an attachment hole of an attachment part so as to be replaceable and performing welding, and automatically replacing the electrode bar. The welding positioning device includes a bar-shaped grip part that can be gripped in the attachment part in a state of being inserted to the attachment hole coaxial with the electrode bar. The welding positioning device includes a light emission part 82 that can be attached to the attachment part via the grip part and emits light L to a position where welding is performed when the electrode bar is attached in a state of being attached to the attachment part.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a welding positioning device and a welding positioning method. [Background technology]

[0002] Patent Document 1 discloses an automatic tungsten electrode replacement device. The welding robot constituting the automatic tungsten electrode replacement device performs welding using a tungsten electrode attached to a TIG arc welding torch. When the attached tungsten electrode deteriorates, the welding robot automatically replaces the deteriorated tungsten electrode with a new tungsten electrode prepared in the electrode station.

[0003] Patent Document 2 discloses a welding manipulator teaching device. The welding manipulator teaching device is equipped with an optical mechanism in which a projector and a camera are arranged inside the casing of a welding nozzle. The welding manipulator teaching device irradiates a laser beam from an optical device replaced with the welding nozzle onto a welding workpiece, detects deviation from the weld line of the welding workpiece, and adjusts the deviation. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 4-4979 [Patent Document 2] JP 2011-255473 A Summary of the Invention [Problem to be solved by the invention]

[0005] When performing a teaching operation using such a welding manipulator teaching device, the operator must remove the welding nozzle from the welding manipulator and attach an optical device to the location where the welding nozzle was removed. This requires a lot of time and effort in preparation for the teaching operation.

[0006] The present invention has been made in consideration of the above problems, and has an object to make it possible to facilitate the preparation work when carrying out a teaching work. [Means for solving the problem]

[0007] According to one aspect of the present invention, there is provided a welding positioning device for a welding robot that has the function of aligning an electrode rod, which is replaceably attached to a mounting hole of a mounting part, to a welding part and welding the electrode rod, and automatically replacing the electrode rod. The welding positioning device includes a rod-shaped gripping portion that can be held by the mounting part when inserted into the mounting hole that is coaxial with the electrode rod, and a light-emitting portion that can be attached to the mounting part via the gripping portion and that irradiates light onto a position to be welded when the electrode rod is attached while attached to the mounting part. Effect of the Invention

[0008] According to one aspect of the present invention, the welding positioning device has a rod-shaped gripping portion that can be gripped by the mounting portion of the welding robot, and can be attached to the welding robot by inserting the gripping portion into the mounting hole of the welding robot and gripping the gripping portion with the mounting portion. Therefore, by utilizing the automatic electrode rod replacement function of the welding robot, the welding positioning device can be attached to the mounting portion of the welding robot.

[0009] Therefore, compared to when the worker removes the welding nozzle from the welding robot, attaches the optical device to the welding robot, and then performs the teaching work, the worker does not need to remove the welding nozzle, making it possible to facilitate the preparation work before the teaching work.

[0010] The welding positioning device further includes a light emitting unit that, when attached to the attachment unit via the gripper, irradiates light onto the position to be welded when the electrode rod is attached to the attachment unit. Therefore, when the welding positioning device is attached to the welding robot, the light emitting unit can irradiate light onto the position to be welded.

[0011] Therefore, for example, teaching work can be performed by aligning the irradiation position of the light emitted from the light emitting unit with the welding portion. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view showing a welding robot to which a welding positioning device according to this embodiment is attached. [Diagram 2] FIG. 2 is a cross-sectional view showing a main part of a welding device provided on a robot arm of a welding robot. [Diagram 3] FIG. 3 is an explanatory diagram showing a procedure for replacing an electrode rod by a welding robot. [Figure 4] FIG. 4 is a perspective view showing the welding positioning device according to the present embodiment. [Diagram 5] FIG. 5 is a flowchart showing the operation of the welding robot. [Figure 6] FIG. 6 is an explanatory diagram showing a state in which the welding positioning device according to this embodiment is attached to a welding robot. [Figure 7] FIG. 7 is an explanatory diagram showing a teaching operation performed using the welding positioning device according to this embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, the welding positioning device 10 (see FIG. 4) and the welding positioning method according to the present embodiment will be described with reference to the accompanying drawings. First, the welding robot 12 to which the welding positioning device 10 is attached will be described.

[0014] Fig. 1 is a perspective view showing a welding robot 12 to which a welding positioning device 10 (see Fig. 7) according to this embodiment is attached. Fig. 2 is a cross-sectional view showing a main part of a welding device 16 provided on a robot arm 14 of the welding robot 12. Fig. 3 is an explanatory diagram showing a procedure for replacing an electrode rod 20 in the welding robot 12.

[0015] 1, welding robot 12 is a device that welds a weld 34, which is a position where a first workpiece 30 and a second workpiece 32, which are base materials, are welded to each other. Welding robot 12 includes a robot body 40, a robot arm 14 that extends from robot body 40, and a welding device 16 that is attached to the tip of robot arm 14. Welding robot 12 is controlled by a controller 42.

[0016] The welding robot 12 is a multi-axis robot. The welding robot 12 operates the robot arm 14 in accordance with commands from a controller 42, and controls the position and orientation of the welding device 16 in six axial directions (X-axis, Y-axis, Z-axis, and rotation directions around each axis).

[0017] The controller 42 controls the operation of the welding robot 12. The controller 42 is composed of a microcomputer equipped with a CPU, RAM, ROM, an input / output interface, etc. The CPU of the controller 42 reads and executes programs stored in the ROM to perform various processes. The controller 42 can also be composed of multiple microcomputers.

[0018] 2, the welding device 16 is a device for performing, for example, TIG (Tungsten Inert Gas) welding. A welding torch 50 is provided at the tip of the welding device 16.

[0019] The welding torch 50 includes a hollow nozzle 52 and an attachment portion 54 provided inside the nozzle 52. The nozzle 52 is formed in a cylindrical shape. A tapered portion 56 that tapers toward the tip is formed at the tip of the nozzle 52. The tip of the tapered portion 56 is open.

[0020] A shielding gas 58 is supplied between the nozzle 52 and the attachment portion 54. The shielding gas 58 is collected toward the center by the tapered portion 56 of the nozzle 52 and is supplied around the electrode rod 20 protruding from the tapered portion 56. The attachment portion 54 is formed in a cylindrical shape. A circular attachment hole 60 opens at the tip of the attachment portion 54. The attachment hole 60 can insert a cylindrical electrode rod 20 used in TIG welding.

[0021] The mounting portion 54 is provided with a gripping mechanism (not shown) on the base end side for gripping the electrode rod 20 inserted into the mounting hole 60. The gripping mechanism is constituted by, for example, a collet chuck mechanism. The gripping mechanism operates according to commands from the controller 42 (see FIG. 1). The gripping mechanism forms a gripping state in which the electrode rod 20 is gripped, and a released state in which the gripping state is released. The electrode rod 20 is gripped in a state where it protrudes from the tapered portion 56 of the nozzle 52.

[0022] A voltage is applied from a welding power source between the electrode rod 20 and the base material such as the first workpiece 30 and the second workpiece 32. An arc discharge is generated between the electrode rod 20 and the base material. The arc discharge is generated in a shielding gas 58 supplied from a nozzle 52. The heat of this arc discharge melts, for example, the base material and a filler rod (not shown), and welding is performed.

[0023] As a result, the welding robot 12 aligns the electrode rod 20, which is replaceably attached to the mounting hole 60 of the mounting portion 54, with the welding portion 34 and performs welding.

[0024] The welding robot 12 has a function of automatically replacing the electrode rod 20 attached to the mounting hole 60. The automatic replacement function is performed in response to a command from the controller 42. This automatic replacement function will be briefly described.

[0025] 3, when replacing the electrode rod 20 attached to the attachment portion 54 (see FIG. 2) of the welding torch 50, the controller 42 operates the welding robot 12 to move the welding torch 50 to which the electrode rod 20 is attached onto a collection box 72 provided on the replacement table 70. In this state, the controller 42 releases the gripping mechanism, and drops the electrode rod 20 that was gripped by the gripping mechanism into the collection box 72 (step S10).

[0026] Then, the controller 42 operates the welding robot 12 to move the welding torch 50 to above the electrode rod 20 prepared on the exchange table 70, and inserts the electrode rod 20 into the mounting hole 60 of the mounting portion 54. In this state, the controller 42 puts the gripping mechanism into a gripping state, and causes the electrode rod 20 to be held by the mounting portion 54 (step S12).

[0027] Next, the controller 42 operates the welding robot 12 to move the welding torch 50 (step S14), and brings the electrode rod 20 extending from the nozzle 52 of the welding torch 50 into contact with the upper surface of the exchange table 70 or the like. In this state, the controller 42 releases the gripping mechanism and lowers the welding torch 50 to adjust the amount of protrusion of the electrode rod 20 from the tip of the nozzle 52, and then places the gripping mechanism in the gripping state to fix the electrode rod 20.

[0028] Then, the controller 42 operates the welding robot 12 to move the welding torch 50, in which the electrode rod 20 has been replaced (step S16), to the welding portion 34 (step S18), and starts welding.

[0029] Next, the welding positioning device 10 according to this embodiment will be described with reference to Fig. 4. Fig. 4 is a perspective view showing the welding positioning device 10 according to this embodiment.

[0030] As shown in Fig. 4, the welding positioning device 10 includes a rod-shaped gripping part 80 that can be gripped by the mounting part 54 (see Fig. 2) in a state where it is inserted into the mounting hole 60 that is coaxial with the electrode rod 20 described above. The welding positioning device 10 also includes a light-emitting part 82 that can be attached to the mounting part 54 via the gripping part 80 and that irradiates light L (see Fig. 7) to the position (34) to be welded when the electrode rod 20 is attached in a state where it is attached to the mounting part 54.

[0031] The light L is a ray that travels in a straight line. An example of a ray that travels in a straight line is a laser beam. The light emitting unit 82 can be a laser pointer that irradiates a laser beam that travels in a straight line.

[0032] The welding positioning device 10 also includes a power supply unit 84 that supplies power to the light-emitting unit 82. The power supply unit 84 is a dedicated power supply that supplies power only to the light-emitting unit 82. The gripper 80 is provided on a holding member 86 that holds the light-emitting unit 82.

[0033] More specifically, the light-emitting unit 82 is formed in a cylindrical shape and includes a light source therein. The light source is, for example, a laser light source. A transmission window 88 that transmits light L (see FIG. 7) emitted from the light source is provided on the tip surface of the light-emitting unit 82. This allows the light-emitting unit 82 to emit light L along a central axis 90 of the light-emitting unit 82.

[0034] The holding member 86 is formed in a cylindrical shape. A holding hole 92 is formed in the tip surface of the holding member 86. The base end of the light emitting unit 82 is replaceably inserted into the holding hole 92. As a result, the light emitting unit 82 is held by the holding member 86 in a state where it is inserted into the holding hole 92.

[0035] The gripping portion 80 extends from the base end surface of the holding member 86. The gripping portion 80 is formed in a cylindrical shape. The gripping portion 80 has the same cross-sectional shape as the electrode rod 20. More specifically, the gripping portion 80 has approximately the same cross-sectional shape as the electrode rod 20 (see FIG. 2, etc.) attached to the welding robot 12, and has approximately the same outer diameter dimension as the electrode rod 20.

[0036] In this embodiment, the gripping portion 80 has substantially the same cross-sectional shape as the electrode bar 20 and substantially the same outer diameter as the electrode bar 20, but this embodiment is not limited to this. The gripping portion 80 may have a cross-sectional shape slightly different from that of the electrode bar 20 or an outer diameter slightly different from that of the electrode bar 20, as long as it can be inserted into the mounting hole 60 in which the electrode bar 20 is attached and can form a gripped state and a released state by the gripping mechanism.

[0037] The central axis 90 of the gripping part 80, the central axis 90 of the holding member 86, and the central axis 90 of the light emitting part 82 held by the holding member 86 are aligned with each other. When the welding positioning device 10 is attached to the mounting part 54, the central axis 90 of the gripping part 80 is aligned with the central axis of the mounting hole 60. When the electrode rod 20 is attached to the mounting part 54, the central axis of the electrode rod 20 is aligned with the central axis of the mounting hole 60. That is, the central axis of the light L when the welding positioning device 10 is attached to the mounting part 54 (the central axis 90 of the gripping part 80) is aligned with the central axis of the electrode rod 20 when the electrode rod 20 is attached to the mounting part 54. The light emitting part 82 is disposed on the central axis 90 of the gripping part 80, and the light emitting part 82 irradiates the light L on an extension of the central axis 90 of the gripping part 80.

[0038] The power supply unit 84 is composed of a battery. The power supply unit 84 supplies power to the light emitting unit 82. This allows the welding positioning device 10 to emit the light L independently without extending a harness for power supply.

[0039] The power supply unit 84 is formed in a cylindrical shape with a smaller diameter than the holding member 86. The length of the power supply unit 84 is set to be approximately the same as the length of the holding member 86. The power supply unit 84 is held by the holding member 86 in a state of being in close contact with the side portion of the holding member 86.

[0040] In this embodiment, the case where the grip portion 80 is provided on the holding member 86 that holds the light-emitting portion 82 will be described as an example, but the embodiment is not limited to this configuration. For example, the grip portion 80 may have a structure in which it extends directly from the light-emitting portion 82. In a structure in which the grip portion 80 extends from the light-emitting portion 82, the power supply portion 84 is disposed on the side of the light-emitting portion 82.

[0041] (Operation description) Next, the operation of the welding robot 12 will be described with reference to Figures 5 to 7. The welding positioning method according to this embodiment is realized by the operation of the welding robot 12.

[0042] Fig. 5 is a flow chart showing the operation of the welding robot 12. Fig. 6 is an explanatory diagram showing how the welding positioning device 10 according to this embodiment is attached to the welding robot 12. Fig. 7 is an explanatory diagram showing how a teaching operation is performed using the welding positioning device 10 according to this embodiment.

[0043] When the CPU operates according to a processing program stored in a memory such as a ROM to execute the teaching process, controller 42 actuates welding robot 12 to move welding torch 50 to which electrode rod 20 is attached to a removal position (step SB10). More specifically, controller 42 moves welding torch 50 onto electrode rod holder 93 (see FIG. 6) provided on arrangement table 91, which serves as the removal position.

[0044] Furthermore, the controller 42 operates the welding robot 12 to lower the welding torch 50 and hold the electrode rod 20 in the electrode rod holding portion 93. Then, the controller 42 releases the gripping mechanism and raises the welding torch 50, thereby removing the electrode rod 20 that was attached to the mounting hole 60 of the mounting portion 54 (step SB12).

[0045] Furthermore, the controller 42 operates the welding robot 12 to move the welding torch 50 having the attachment portion 54 from which the electrode rod 20 has been removed, to the arrangement position 94 of the arrangement table 91 on which the welding positioning device 10 is arranged (step SB14).

[0046] Furthermore, controller 42 operates welding robot 12 to lower welding torch 50 and insert gripping portion 80 of welding positioning device 10 into mounting hole 60 of mounting portion 54 of welding torch 50 (step SB16). In this state, controller 42 sets the gripping mechanism to the gripping state to grip gripping portion 80 of welding positioning device 10 inserted into mounting hole 60 to mounting portion 54 (gripping step), and attaches welding positioning device 10 to mounting portion 54 of welding torch 50 (step SB18).

[0047] Next, controller 42 operates welding robot 12 to move welding torch 50, to which welding positioning device 10 is attached, to welding portion 34 (see FIG. 7) as the position to be welded (step SB20). Then, light L emitted from light-emitting unit 82 of welding positioning device 10 is irradiated onto welding portion 34 as the position to be welded at the destination (irradiation step). Using light L from light-emitting unit 82, controller 42 performs a teaching process (step SB22) and then ends the teaching process.

[0048] Specifically, the teaching process is a process in which a teaching operation is performed to have welding robot 12 store the operations of welding. In the teaching operation, the worker operates robot arm 14 while visually checking that light L from welding positioning device 10 moves along welding portion 34, which is the position where first workpiece 30 and second workpiece 32 are welded, and stores the coordinates of the operation trajectory in welding robot 12.

[0049] (Action and Effects) The main functions and effects of the welding positioning device 10 and the welding positioning method configured as above will be summarized.

[0050] (1) The welding positioning device 10 is a positioning device for a welding robot 12 that has the function of aligning the electrode rod 20, which is replaceably attached in the mounting hole 60 of the mounting part 54, with the welding part 34 for welding, and automatically replacing the electrode rod 20. The welding positioning device 10 is equipped with a rod-shaped holding part 80 that can be held by the mounting part 54 in a state where it is inserted into the mounting hole 60 that is coaxial with the electrode rod 20. The welding positioning device 10 is attachable to the mounting part 54 via the holding part 80, and is equipped with a light-emitting part 82 that irradiates light L to the position (34) to be welded when the electrode rod 20 is attached in a state where it is attached to the mounting part 54.

[0051] (6) The welding positioning method is a positioning method for a welding robot 12 having a function of aligning and welding an electrode rod 20, which is replaceably attached in a mounting hole 60 of a mounting portion 54, with a welding portion 34 and automatically replacing the electrode rod 20. The welding positioning method includes a holding step (step SB18) of inserting a rod-shaped holding portion 80 into the mounting hole 60, which is coaxial with the electrode rod 20, and holding the holding portion 80 on the mounting portion 54. The welding positioning method also includes an irradiation step (step SB22) of irradiating light L by a light emitting portion 82 attached to the mounting portion 54 via the holding portion 80 to a position (34) to be welded when the electrode rod 20 is attached to the mounting portion 54.

[0052] According to this embodiment, the welding positioning device 10 is provided with a rod-shaped gripping portion 80 that can be gripped by the mounting portion 54 of the welding robot 12. Therefore, the welding positioning device 10 can be attached to the welding robot 12 by inserting the gripping portion 80 into the mounting hole 60 of the welding robot 12 and gripping the gripping portion 80 by the mounting portion 54. As a result, the welding positioning device 10 can be attached to the mounting portion 54 of the welding robot 12 by utilizing the automatic electrode rod 20 replacement function of the welding robot 12.

[0053] Therefore, compared to a case where the worker removes the welding torch 50 from the welding robot 12, attaches the optical device to the welding robot 12, and then performs the teaching work, the worker does not need to remove the welding torch 50, and the preparation work before the teaching work can be facilitated.

[0054] Furthermore, the welding positioning device 10 includes a light-emitting unit 82 that irradiates light L onto the position (34) to be welded when the electrode rod 20 is attached to the attachment unit 54 in a state where the welding positioning device 10 is attached to the attachment unit 54 via the gripping unit 80. Therefore, with the welding positioning device 10 attached to the welding robot 12, the light-emitting unit 82 can irradiate light L onto the position (34) to be welded.

[0055] Therefore, for example, by aligning the irradiation position of the light L emitted from the light emitting unit 82 with the welding portion 34 as the position to be welded, it is possible to perform a teaching operation.

[0056] By using the light emitting unit 82 that irradiates the light L, the worker can perform a teaching operation to memorize the position coordinates of the welding torch 50 in the same state as during welding using the electrode rod 20. Therefore, the welding robot 12 that has performed the teaching operation using the welding positioning device 10 can improve the welding quality.

[0057] The welding positioning method (6) of this embodiment can also provide the same effects as those described above.

[0058] (2) In the welding positioning device 10 , the gripping portion 80 has the same cross-sectional shape as the electrode rod 20 .

[0059] According to this embodiment, it is easier to hold the gripping portion 80 in the mounting hole 60 of the mounting portion 54 than when the cross-sectional shape of the gripping portion 80 is different from that of the electrode rod 20 .

[0060] (3) The welding positioning device 10 further includes a power supply unit 84 that supplies power to the light emitting unit 82 .

[0061] According to this embodiment, power can be supplied to the light-emitting unit 82 without receiving power from an external source. Therefore, compared to a case where a power supply harness must be extended from the welding positioning device 10, wiring work is not required, and the movable range of the welding robot 12 can be expanded.

[0062] (4) The grip portion 80 is provided on a holding member 86 that holds the light-emitting portion 82 .

[0063] In this embodiment, the light emitting unit 82 is held by a holding member 86 provided with a gripping portion 80. Therefore, by devising the shape of the holding member 86, it becomes possible to use a commercially available light emitting unit 82, which enables cost reduction. In addition, the light emitting unit 82 can be replaced, which improves convenience.

[0064] (5) The welding positioning device 10 further includes a power supply unit 84 that supplies power to the light emitting unit 82 , and the power supply unit 84 is held by a holding member 86 .

[0065] According to this embodiment, the welding positioning device 10 can supply power to the light emitting unit 82 without receiving power from an external source. Therefore, compared to a case where a power supply harness must be extended from the welding positioning device 10, wiring work is not required, and the movable range of the welding robot 12 can be expanded.

[0066] The light emitting unit 82 is held by a holding member 86 provided with a gripping portion 80. Therefore, by devising the shape of the holding member 86, it becomes possible to use a commercially available light emitting unit 82, which allows for cost reduction. In addition, the light emitting unit 82 can be replaced, which improves convenience.

[0067] Although the embodiments of the present invention have been described above, the above-mentioned embodiments merely show some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above-mentioned embodiments.

[0068] In the above embodiment, the welding robot 12 to which the welding positioning device 10 is attached performs TIG welding, but the welding robot 12 is not limited to a robot that performs TIG welding. The welding robot 12 may be, for example, a robot that performs arc welding without using the shielding gas 58. [Explanation of symbols]

[0069] 10 Welding positioning device 12 Welding robot 20 electrode rod 34 Welding 42 Controller 54 Mounting part 60 mounting holes 80 Gripping part 82 Light emitting part 84 Power supply section 86 Retaining member 90 center axis L light

Claims

1. A welding positioning device for a welding robot having a function of aligning an electrode replaceably attached to a mounting hole of a mounting portion with a welding portion and welding the electrode, and automatically replacing the electrode, a rod-shaped gripping portion that can be gripped by the mounting portion in a state where the rod-shaped gripping portion is inserted into the mounting hole that is coaxial with the electrode rod; a light emitting portion that can be attached to the attachment portion via the gripping portion and that irradiates light onto a position to be welded when the electrode rod is attached in a state where the light emitting portion is attached to the attachment portion; A welding positioning device comprising:

2. 2. The weld positioning device of claim 1, The gripping portion has the same cross-sectional shape as the electrode rod. Welding positioning device.

3. The welding positioning device according to claim 1 or 2, Further comprising a power supply unit for supplying power to the light emitting unit. Welding positioning device.

4. The welding positioning device according to claim 1 or 2, The gripping portion is provided on a holding member that holds the light emitting portion. Welding positioning device.

5. 5. The weld positioning device of claim 4, A power supply unit that supplies power to the light-emitting unit, The power supply unit is held by the holding member. Welding positioning device.

6. A welding positioning method for a welding robot having a function of aligning an electrode replaceably attached to a mounting hole of a mounting portion to a welding portion and welding the electrode, and automatically replacing the electrode, comprising: a gripping step of inserting a rod-shaped gripping portion into the mounting hole that is coaxial with the electrode rod and gripping the gripping portion to the mounting portion; an irradiation step of irradiating light to a position to be welded when the electrode rod is attached to the attachment portion by a light emitting unit attached to the attachment portion via the gripping unit; Equipped with Welding positioning method.

Images