JPS6240983A - Automatic welding equipment for linear weld zone - Google Patents

Abstract

PURPOSE:To perform the welding of a linear weld zone simply and with high accuracy by correcting the laser beam detected by a laser beam photodetector by a correcting means so that it becomes parallel apparently to the linear weld zone. CONSTITUTION:A laser beam position detecting part 16 detects the laser beam detecting position of a laser beam photodetector 7 and sends out the detecting output thereof to a photodetector position correction quantity arithmetic part 17. The arithmetic part 17 operates the horizontal movement of the first arm 12, gives the arithmetic output to the first driving part 14 and controls the horizontal movement of the arm 12 so as to detect the laser beam at the center part of the first laser beam photodetector 7 based on the detected output thereof. A torch position correction quantity arithmetic part 20 operates the horizontal movement of the second arm 13 so that a torch 6 is located on the linear weld zone 2 based on the calculated output from the carriage moving quantity calculating part 19 and the laser beam detecting position output of the second layer detector, etc. This arithmetic output is given to the second driving part 15 to control the horizontal movement of the second arm 13. The laser beam thus becomes parallel to the weld zone 2 apparently.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an automatic straight welding device used for automatic welding of flat plate joints, etc., and particularly to an automatic welding device for straight welds that is used to automatically weld flat plate joints, etc. Concerning improvement of control means.

[Conventional technology]

Conventionally, when automatically welding a straight welding part such as a flat plate joint, welding was usually performed by laying a rail along the welding part and moving an automatic welding machine on the rail.

In addition, the welding groove position may be detected using an eddy current sensor or a visual sensor, and an automatic welding machine may be moved in accordance with the detected output to perform welding.

[Problem that the invention seeks to solve]

However, when laying the rails and performing automatic welding, the length of each rail is only about 2 to 3 meters, so
In order to continuously and automatically weld straight line welds over several meters long, it was necessary to connect multiple rails. For this reason, it was difficult to make the entire rail completely straight, and it was also difficult to make it completely parallel to the straight welds. Therefore, it was not possible to perform welding with high precision.

On the other hand, when welding is performed using an eddy current sensor, the eddy current sensor detects the gap in a straight weld and performs positioning, so this straight weld has a linear groove shape. However, if they are in close contact with each other, the position detection accuracy will decrease.

For this reason, it lacked practicality. Further, when welding is performed using a visual sensor, at least an image processing device is required. For this reason, the entire device becomes very large-scale, and is also problematic in terms of cost. In addition, external conditions such as the brightness of the place where welding is performed and the dirt on the plates to be welded must be kept constant, so it cannot be carried out easily.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an automatic welding device for straight welds that can easily and accurately weld straight welds.

Means for Solving Problem C] In order to solve the above problems and achieve the object, the present invention provides a laser transmitter that emits a laser beam so as to form a plane perpendicular to the straight welding part, and also provides the above-mentioned method. A welding cart that moves a welding torch in the welding direction for welding a straight line weld is provided with a laser receiver that receives the laser light emitted from the laser transmitter, and the laser light received by the laser receiver is used to move the welding torch in the welding direction. This is corrected so that it appears parallel to the welded part.

[Effect]

By taking such measures, it is possible to always move the welding torch provided on the welding carriage to follow the straight welding part with a simple and inexpensive configuration.

〔Example〕

FIG. 1 is a schematic diagram of an embodiment in which the present invention is applied to welding a straight weld portion 2 in a welded member 1 to which flat plates 1a and lb are temporarily attached. In the figure, reference numeral 3 denotes a laser beam transmitter, which emits a laser beam 4 while rotating it so as to form a plane perpendicular to the linear welded portion 2. Reference numeral 5 denotes an automatic welding cart movable in the welding direction, and the automatic welding cart 5 includes a welding torch 6 for welding the straight welding portion 2, a first laser receiver 7 for receiving the laser beam 4, and the like. installed. Further, a second
A laser receiver 8 is attached.

FIG. 2 is a block diagram showing the configuration of the automatic welding cart 5. As shown in FIG. The automatic welding cart main body 11 includes a first arm 12 to which the first laser receiver 7 is attached, and a welding torch 6.
A second arm 13 having attached thereto is provided, and these first and second arms 13 are provided. The second arm 12.13G and the first arm respectively. The second drive unit 14.15 horizontally moves the straight weld 8I12 so as to be perpendicular to the straight weld 8I12. In addition,
The first arm 12 is not affected by the movement of the second arm 13, but the second arm 13 is configured to move in the same direction by the same amount of movement in response to the movement of the first arm 12. There is.

Reference numeral 16 denotes a laser beam position detecting section for detecting the laser beam receiving position of the laser beam receiver 7, and this detection output is sent to the light receiver position correction amount calculating section 17. Based on the detection output from the laser beam position detection section 16, the receiver position correction amount calculating section 17 adjusts the first laser beam 4 so that the laser beam 4 is received at the center of the first laser beam receiver 7. 1 arm 1
This calculation output is given to the first drive section 14, and the horizontal movement amount of the first arm 12 is calculated.
It controls the horizontal movement of the

On the other hand, the automatic welding truck body 11 has this truck body 11
A counter 18 for counting the number of wheel rotations is provided,
The wheel rotation speed counted by this counter 18 is output to a bogie movement amount calculation section 19.

The cart movement amount calculation unit 19 calculates the movement amount of the automatic welding cart main body 11 from the wheel rotation speed given from the counter 18 and the preset wheel diameter, and this calculation output is It is output to the torch position correction amount calculation section 20. The torch position correction amount calculating section 20 determines that the welding torch 6 is always in a straight welding section based on the calculation output from the cart movement amount calculating section 19 and the laser beam receiving position output of the second laser receiver 8. said second so as to be located on the second
The horizontal movement amount of the arm 13 is calculated, and the calculation output is given to the second drive section 15 to control the horizontal movement of the second arm 13.

In this embodiment configured in this way, the laser beam 4 is emitted from the laser transmitter 3 so as to form a plane perpendicular to the straight welding part 2, and the position of the welding torch 6 is determined based on this laser beam 4. The automatic welding of the straight weld section 2 is controlled.

Here, it is difficult to cause the laser beam transmitter 3 to emit the laser beam 4 so as to be parallel to the linear welded portion 2. Therefore, the first laser beam 4 is arranged so that the laser beam 4 is apparently parallel to the straight welding part 2. Second arm 12.1
The horizontal movement of No. 3 is calculated, and the calculation output is used to calculate the horizontal movement of No. 3.
By controlling the second drive 14.15, the welding torch 6 is always positioned over the straight weld 2.

As shown in Figure 3, the total weld length is L, and the straight weld part 2
The distance from to the laser transmitter 3, the so-called laser transmitting position, is Wl, and the distance from the straight welding part 2 to the laser beam receiving position of the second laser receiver 8, the so-called laser end position, is Wl.
Set it to 2. Then, the distance W3 from the straight welding part 2 to the laser beam 4 at the position of the weld length L1 is W3=11/L (W2-Wl)+W1...
It is determined by the formula (1).

Therefore, from the first laser beam receiver 7 to the welding torch 6
1st so that the distance to W3 is W3. second arm 12
．． By controlling the laser beam 13, the laser beam 4 is apparently parallel to the straight welding part 2. Here, the total weld length [and the laser emission position W1 are preset values, the laser end position W2 is detected by the second laser receiver 8,
The length L1 to be welded is calculated by the cart movement amount calculating section 19.

Further, the first laser receiver 7 has a laser beam 4 at its center.
Since the position is controlled to receive the laser beam 4,
move parallel to Therefore, ΔW −W 3− W
1-11/L (W2-Wl) ...(2
) by the torch position correction amount calculation section 20, and by controlling the second drive section 15 based on the calculation output,
The welding torch 6 always traces the welding groove of the straight welded part 2.

Thus, according to this embodiment, the welding torch 6 attached to the automatic welding cart 5 is guided by the laser beam 4 corrected so that it is apparently parallel to the straight welding part 2, and the welding torch 6 is guided to the straight welding part 2. Move while following the welding groove. Therefore, there is no need to lay a rail or detect the position using an eddy current sensor or a visual sensor as in the conventional method. Since it is sufficient to transmit the signal parallel to the portion 2, it is possible to trace the welding groove with high accuracy with a simple and inexpensive configuration. Furthermore, since there is no need to perform image processing, there is no need for the apparatus to become large-scale, and there is no need for complicated conditions such as keeping the brightness in the room constant, the dirt on the workpiece 1, etc. to be constant. As a result, automatic welding of the straight weld portion 2 can be easily performed.

Note that the present invention is not limited to the above embodiments.

For example, in the above embodiment, a case was shown in which the laser beam 4 was rotated to form a -〇 plane perpendicular to the straight welding part 2;
Since it is only necessary for the laser light receiving sections 7 and 8 to receive the laser light 4 almost simultaneously, the laser light 4 may be transmitted in vibration over a predetermined angle, or may be transmitted in a fan shape using a prism or the like. Further, in the above embodiment, the automatic welding cart 5
Although the case where calculation is performed using the wheel rotation speed and the diameter of the wheel as the position detecting means is shown, other position detecting means may be applied.

Further, in the above embodiment, the present invention was applied to automatic welding of flat plates 1a and 1b, but the present invention is not limited to this, and can be applied to any automatic welding of straight welded parts. It goes without saying that various other modifications can be made without departing from the gist of the present invention.

(Effects of the Invention) As detailed above, the present invention provides a laser oscillator that emits laser light so as to form a plane perpendicular to the linear weld, and a welding torch that welds the linear weld. A welding cart that is moved in the welding direction is provided with a laser receiver that receives the laser light emitted from the laser transmitter, and the laser light received by the laser receiver is apparently parallel to the straight welding part. This is corrected as follows.

Therefore, according to the present invention, with a simple and inexpensive configuration,
Since the welding torch provided on the welding cart can always be moved following the straight welding part, it is possible to provide an automatic welding device for the straight welding part which can simply and accurately weld the straight welding part.

[Brief explanation of the drawing]

FIGS. 1 to 3 are diagrams showing an embodiment of the present invention,
FIG. 1 is a schematic diagram showing the general configuration, FIG. 2 is a block diagram showing the configuration of the automatic welding cart, and FIG. 3 is a diagram for explaining the function and effect. DESCRIPTION OF SYMBOLS 1... Member to be welded, 2... Straight line welding part, 3... Laser light transmitter, 4... Laser light, 5... Automatic welding trolley, 6... Welding torch, 7.8 ...First. second laser receiver, 12.13...first. second arm, 1
4゜15...1st. Second driving unit, 16... Laser beam position detection unit, 17... Light receiver position correction amount calculation unit, 1
8... Counter, 19... Cart movement amount calculation unit, 20.
・・１・−chi position correction prostitute Hanbu.

Claims (1)

[Claims] A welding torch that welds a straight weld, a welding cart that moves the welding torch in the welding direction, a laser transmitter that emits laser light so as to form a plane perpendicular to the straight weld, and this laser transmitter. a laser receiver provided on the welding cart so as to receive laser light emitted from the welding cart; and a correction means for correcting the laser light received by the laser receiver so that it is apparently parallel to the straight welding part. An automatic welding device for straight welding parts, characterized by comprising: