JP2010046699A - Method for adjusting laser head torch, laser head torch, and welding robot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for adjusting a laser head torch capable of accurately and effectively adjusting the laser head torch in a target direction when operating a welding robot, and to provide a laser head torch, and a welding robot. <P>SOLUTION: A welding robot 1 is provided with: a wrist part 26, on which a laser torch 53 is mounted; at least one arm-part 25 connected continuously to the wrist part 26; and a controller 30, which stores a teaching operation of the wrist part 26. An angle measuring instrument 28 is provided so as to keep the relative direction thereof to the wrist part 26 or the optical axis of the laser head torch. The angle of the laser torch 53 is adjusted into a target angle, by operating the wrist part 26 and the arm-part 25 based on the values measured by the angle measuring instrument 28. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for adjusting a laser head torch, a laser head torch, and a welding robot.

  As is well known, welding operations using robots are performed in various industrial fields. For example, it is possible to work at high speed, welding in a narrow place, welding over a wide range, and obtaining a uniform welding quality. It is widely used because it has many advantages compared to manual welding work, such as being able to weld in a dangerous working environment.

  On the other hand, in recent years, a technique related to laser-arc hybrid welding has been disclosed in order to improve the welding quality by increasing the penetration of welding metal such as a welding wire during welding (see, for example, Patent Document 1).

Of course, when performing welding using a laser head torch, it is important to irradiate the laser beam with its optical axis accurately directed at the object to be welded. It is particularly important to accurately irradiate the laser beam irradiated from the laser head torch to the welding object in the vicinity of the supplied welding wire tip, and the moving path of the laser head torch and the optical axis of the laser head torch. It is necessary to memorize the direction of the position accurately by teaching operation.
JP 2005-238282 A

However, the robot has various drive parts and transmission parts, and the optical axis of the laser head torch is the object to be welded due to rattling caused by the manufacturing accuracy of these drive parts and transmission parts, backlash, and wear due to aging. There is a possibility that it will face away from the direction.
Also, even when welding with different weights of laser head torch, or when using one laser head torch, the horizontal distance from the fulcrum of the arm portion to the laser head torch and when the inclination of the arm portion changes The bending moment is changed, and the deflection generated in the arm portion is different, which may cause a deviation in the optical axis of the laser head torch.
As a result, there may be a difference between the target direction in which the laser head torch is to be directed during operation or teaching operation and the direction of the optical axis of the laser head torch.

  Therefore, when teaching operation is performed prior to welding using the laser head torch, an angle meter is applied to the laser head torch to measure the direction of the laser head torch, and the angle error generated on the optical axis of the laser head torch is adjusted to be small. While teaching the direction of the laser head torch. Therefore, establishment of a method for accurately and efficiently adjusting the direction of the optical axis of the laser head torch and specific technical means for realizing the method are required.

  The present invention has been made in consideration of such circumstances, and a laser head torch adjustment method and laser head capable of accurately and efficiently adjusting a laser head torch in a target direction in a welding robot, An object is to provide a torch and a welding robot.

In order to solve the above problems, the present invention proposes the following means.
According to a first aspect of the present invention, there is provided a laser head torch for adjusting a direction of the laser head torch in a welding robot having a wrist portion provided with a laser head torch and at least one arm portion connected to the wrist portion. The angle measurement device so that the relative direction with respect to the wrist or the optical axis of the laser head torch is maintained, the wrist based on the measurement value of the angle measurement device, The laser head torch is adjusted to a target angle which is a target by operating the arm portion.

According to the method for adjusting a laser head torch according to the present invention, by measuring the direction of the optical axis of the laser head torch by an angle measuring instrument in which the wrist or the relative direction of the optical axis of the laser head torch is held, Even if the orientation of the robot arm or the like is deviated, the optical axis of the laser head torch can be directed to the target value, so the wrist and arm parts are efficiently adjusted so that the optical axis of the laser head torch is at the target angle. Can be adjusted.
As a result, the quality of welding using a laser head torch including laser / arc hybrid welding can be improved.

  The invention according to claim 2 is the laser head torch adjustment method according to claim 1, wherein the robot includes a control unit that stores a teaching operation, and the indication value of the angle measuring device is the target value. The operation is stored in the control unit by moving to an allowable angle range.

  According to the method for adjusting a laser head torch according to the present invention, the teaching operation is performed accurately and efficiently so that the direction of the laser head torch is within the allowable range of the target angle based on the indication value of the angle measuring device. Can do. As a result, since the laser head torch operates within the allowable range of the target angle, the quality of welding using the laser head torch can be improved.

  The invention according to claim 3 is provided in the wrist portion of the robot including a wrist portion, at least one arm portion connected to the wrist portion, and a control unit that stores a teaching operation of the wrist portion. The laser head torch includes an angle measuring device, and the angle measuring device is provided so as to maintain a relative orientation with respect to an optical axis of the laser head torch.

  The invention according to claim 4 is a welding robot comprising a wrist portion provided with a laser head torch, at least one arm portion connected to the wrist portion, and a control unit for storing teaching operation. And an angle measuring device, wherein the angle measuring device is provided so as to maintain a relative orientation with respect to the optical axis of the laser head torch.

  According to the welding robot and the welding laser head torch according to the present invention, since the relative orientation of the angle measuring device and the laser head torch is maintained, the optical axis of the laser head torch is accurately and efficiently set to the target angle. Teaching operation can be performed.

  Invention of Claim 5 is the welding robot of Claim 4, Comprising: The said control part has an angle correction means, The said angle correction means is the said angle measurement apparatus input into the said control part A correction value is calculated based on the measured value and the target value, and the optical axis of the laser head torch can be corrected to an allowable range of the target value when driving based on the memory of the teaching operation. It is characterized by.

  According to the welding robot according to the present invention, the optical axis of the laser head torch can be efficiently corrected within the allowable range of the target value based on the measured value measured by the angle measuring device.

According to the laser head torch adjusting method, laser head torch and welding robot according to the present invention, it is possible to accurately and efficiently grasp the relative difference of the optical axis of the laser head torch used in the welding robot with respect to the target. .
As a result, the direction of the optical axis of the laser head torch can be adjusted.
When applied to a teaching robot, the direction of the optical axis of the laser head torch can be taught accurately and efficiently.

The first embodiment of the present invention will be described below with reference to FIGS.
FIG. 1 is a schematic view showing an example of a welding robot 1 according to the present invention.
The welding robot 1 includes a robot 2 and a laser / arc hybrid welding apparatus 4, and the laser / arc hybrid welding apparatus 4 includes a MIG welding machine 40 and a laser welding machine 50.

The robot 2 includes a robot body 20 and a control unit 30. The robot body 20 is driven by a control signal from the control unit 30, and the control unit 30 performs a teaching operation performed during a welding operation. The operation of the robot body 20 can be stored in the control unit 30.
The control unit 30 is connected to the laser / arc hybrid welding apparatus 4 by a control cable (not shown) so that the welding operation by the laser / arc hybrid welding apparatus 4 can be linked with the operation of the robot body 20. .

  In the first embodiment, the robot body 20 is, for example, a 6-axis control robot that can be controlled to 6 axes as shown in FIG. 1. The robot body base 22 is disposed above the robot body base 22. The base rotating part 23 that is rotatable about the vertical axis in the direction of arrow R1 on the horizontal plane, the first arm part 24 connected to the upper part of the base rotating part 23, and the first arm part 24 A second arm portion 25 connected to the second arm portion 25, and a wrist portion 26 connected to the second arm portion 25.

The first arm portion 24 is connected to the base rotating portion 23 by a horizontally disposed axis J1, and is rotatable about the axis J1 in the direction of the arrow R2 with respect to the base rotating portion 23.
The second arm portion 25 is connected to the first arm portion 24 by a horizontally arranged axis J2, and is rotatable in the direction of arrow R3 about the axis J2 with respect to the first arm portion 24. At the same time, the tip side is rotatable around the longitudinal axis of the second arm portion 25 in the direction of the arrow R4.

The wrist portion 26 is connected to the distal end side of the second arm portion 25 and can rotate about the rotation axis J3 about the arrow R5 to change the crossing angle with the longitudinal axis of the second arm portion 25. In addition, it can be rotated about an arrow R6 around an axis J4 orthogonal to the rotation axis J3.
The wrist 26 is provided with an attachment jig 27, and a torch 41 and a laser torch (laser head torch) 53, which will be described later, are attached.

In this embodiment, the angle measuring device 28 is disposed on the mounting jig 27 as shown in FIG. 2, and coincides with the optical axis of the laser torch (laser head torch) 53 and has a relative orientation with the torch 41. The direction in which the optical axis of the laser torch 53 faces is designated as an angle side constant value θ to the digital display unit 28A.
In this embodiment, the angle measurement value θ of the angle measurement device 28 is arranged so as to coincide with the optical axis of the laser head torch. For example, the angle measurement device 28 is predetermined with respect to the optical axis of the laser head torch. It is good also as a structure which crosses and arrange | positions at an angle (relative angle), correct | amends the angle measurement value, and acquires angle (theta) of an optical axis.

  In addition, as the angle measuring device 28, either an analog method or a digital method can be applied. In the first embodiment, for example, a digital angle meter (product number 76549 manufactured by Shinwa Measurement Co., Ltd.) is used. The angle θ of the laser torch 53 can be displayed on the digital display unit 28A formed of liquid crystal.

The MIG welder 40 includes a torch 41 that generates thermal energy between the welded portion of the object to be welded W, a MIG welder main body 42, and a power supply unit (not shown) that supplies welding power to the torch 41. . The torch 41 is supplied with an inert gas such as argon gas via a pressure hose (not shown).
The MIG welder main body 42 is configured by housing a wire feeding unit for feeding the welding wire M to the torch 41 and a control device such as a switch, and is connected to the power source unit by a cable (not shown). Has been.

The laser welding machine 50 includes a laser oscillator 51, a laser transmission fiber (laser light transmission means) 52, and a laser torch (laser head torch) 53, and the laser light oscillated and generated by the laser oscillator 51 is used for laser transmission. The laser beam is transmitted to the laser torch 53 via the fiber 52 and irradiated from the laser torch 53 to the welded portion of the welding object W.
The laser torch 53 has, for example, a configuration in which a lens for converging the laser light is provided inside a housing in which an optical path through which the laser light passes is formed.

Next, a method for adjusting the direction of the laser torch 53 of the welding robot 1 will be described.
1) First, the mounting jig 27 provided with the laser torch 53 and the angle measuring device 28 in which the relative orientation with the laser torch 53 is held is attached to the wrist portion 26.
A laser torch 53 provided with an angle measuring device 28 in place of the attachment jig 27 may be attached to the attachment jig 27 or the wrist portion 26.
2) Next, the robot body 20 is operated by an operation box (not shown) so that the direction (angle θ) of the laser torch 53 corresponds to the target angle when laser-arc hybrid welding is performed on the welding object W.
3) During operation of the robot body 20, adjustment is performed by operating the wrist or the like so that the indicated value (angle θ) of the angle measuring device 28 matches the target angle of the laser torch 53 or falls within the allowable range of the target angle. .
The permissible range for the target angle is selected based on the convergence state of the laser light emitted from the laser torch 53 and the error of the focal position, and a range in which welding of a predetermined quality is possible by teaching within this permissible range. Is preferred.

According to the method for adjusting the laser torch 53 according to the first embodiment, even when the laser torch 53 moves and the direction (angle θ) changes, the direction can be grasped in real time.
Further, according to the welding robot 1, the direction (angle θ) of the laser torch 53 is adjusted in accordance with the target angle by the angle measuring device 28 in which the relative orientation with the laser torch 53 is maintained. Even if there is a tack, the direction of the laser torch 53 can be accurately adjusted with respect to the target angle.
As a result, teaching work can be performed accurately and efficiently in the welding robot 1.
Further, the quality of the laser / arc hybrid welding can be improved by adjusting the direction of the laser torch 53 within the allowable range of the target angle.

The second embodiment of the present invention will be described below with reference to FIG.
FIG. 3 is a schematic diagram illustrating an example of the welding robot 10 according to the second embodiment.
The robot 10 is different from the robot 1 according to the first embodiment.
1) An angle measuring device 128 is arranged instead of the angle measuring device 28,
2) A control unit 130 is provided instead of the control unit 30, and a signal output from the measuring device 128 is input to the control unit 130.
3) The control unit 130 has angle correction means,
Since the other points are the same as those of the first embodiment, the same reference numerals as those of the first embodiment are given and description thereof is omitted.

The angle measuring device 128 can output an angle detected by an angle sensor (not shown) as an electrical signal.
The control unit 130 includes an angle correction unit, and the angle correction unit includes, for example, an angle correction program stored in a storage medium such as an EPROM. In addition, an electrical signal related to angle measurement from the angle measurement device 128 is input to the control unit 130 via the signal line 131.

For example, the angle correction program calculates an angle measurement value relative to the optical axis of the laser torch 53 based on a signal from the angle measuring device 128 input to the control unit 130, and uses the target value of the optical axis of the laser torch 53. A correction value for directing the optical axis of the laser torch 53 to the target value is calculated.
This correction value is stored in a storage unit (not shown).
When driving based on the data stored in the teaching operation, an operation signal obtained by correcting the operation data stored in the storage unit with the correction value is output, and the optical axis of the laser torch 53 is directed in the target direction. Thus, the arm portion and the like are operated.
Instead of storing the correction value, the corrected data calculated from the target value of the optical axis of the laser torch 53 and the correction value may be stored in the storage unit as data for operating the robot 10.

According to the welding robot 10, the optical axis of the laser head torch 53 can be efficiently corrected within the allowable range of the target value based on the measurement value measured by the angle measurement device 128.
As a result, in the robot 10, teaching can be performed accurately and efficiently so that the optical axis of the laser torch 53 faces the target angle.

Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the invention.
For example, in the above-described embodiment, the case where the angle measuring devices 28 and 128 are attached to the attachment jig 27 provided on the wrist portion 26 of the robot body 20 has been described, but for example, the bracket provided on the attachment jig 27 For example, the angle measuring devices 28 and 128 may be provided via the above.

Alternatively, the angle measuring devices 28 and 128 may be provided directly on the laser torch 53 or attached via an attachment member so that the laser torch 53 and the angle measuring device 28 move integrally.
In the above embodiment, the case where the robot body 20 is a six-axis articulated robot has been described. However, the present invention is applicable to a robot other than a six-axis articulated robot, for example, a robot composed of orthogonally arranged arm portions. May be.

  In the above embodiment, the correction value or the corrected data calculated based on the detection signal detected by the angle measuring device 128 is stored in the storage unit in the teaching work, and the direction of the laser torch 53 is adjusted. However, for example, the direction of the optical axis of the laser torch 53 may be corrected in real time based on the detection signal detected by the angle measuring device 128 during operation.

  In the above embodiment, the case where the laser torch 53 is used for laser / arc hybrid welding has been described. However, the laser torch 53 may be applied to a laser torch used for welding other than laser / arc hybrid welding.

It is a figure showing a schematic structure of a welding robot concerning a 1st embodiment of the present invention. It is a figure which shows schematic structure of the laser torch and angle measuring device which concern on the 1st Embodiment of this invention. It is a figure which shows schematic structure of the welding robot which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

W Welding object 1 Welding robot 4 Laser-arc hybrid welding device 20 Robot body 26 Wrist part 24 First arm part (arm part)
25 Second arm part (arm part)
28, 128 Angle measuring device 30, 130 Control unit 53 Laser torch (laser head torch)

Claims (5)

A wrist portion provided with a laser head torch;
A laser head torch adjusting method for adjusting a direction of the laser head torch in a welding robot having at least one arm connected to the wrist,
An angle measuring device is provided so that the relative orientation with the optical axis of the wrist or the laser head torch is maintained,
A method for adjusting a laser head torch, wherein the laser head torch is adjusted to a target angle by operating the wrist part and the arm part based on a measurement value of the angle measuring device. In the case where the robot includes a control unit that stores a teaching operation,
2. The method of adjusting a laser head torch according to claim 1, wherein the control unit stores the operation by moving the indicated value of the angle measuring device to be within an allowable range of the target angle. The wrist,
At least one arm connected to the wrist;
A laser head torch provided on the wrist part of a robot comprising a control unit for storing teaching operation of the wrist part,
Equipped with angle measuring equipment,
The laser head torch according to claim 1, wherein the angle measuring device is provided so as to maintain a relative orientation with respect to an optical axis of the laser head torch. A wrist portion provided with a laser head torch;
At least one arm connected to the wrist;
A welding robot comprising a control unit for storing teaching operations,
Have angle measuring equipment,
The welding robot according to claim 1, wherein the angle measuring device is provided so as to maintain a relative orientation with respect to an optical axis of the laser head torch. The control unit has angle correction means,
The angle correction means includes
Calculate a correction value based on the measured value and the target value of the angle measuring instrument input to the control unit,
The welding robot according to claim 4, wherein the optical axis of the laser head torch can be corrected to an allowable range of the target value when operating based on the memory of the teaching operation.

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