JPS61150782A - Automatic square welding device - Google Patents

Abstract

PURPOSE:To make possible the unattended operation and automation, etc. of a welding operation by providing a means for maintaining the specified distance between a weld line and torch and torch angle to a carriage and constituting the torch in such a manner that the torch can turn around the arc point. CONSTITUTION:Wheels 12 for moving in a traverse direction and wheels for moving in a longitudinal direction are provided to the carriage 2. A mechanism 7 for lifting the torch 3 and a mechanism 8 for extending or contracting the torch are disposed. Mechanisms 5, 6 for longitudinal and traverse sliding are provided to the carriage 2 to support the mechanism 7 and the mechanism 8. A swiveling mechanism 4 is commanded by a control part 11 to drive the mechanisms 5, 6 and the mechanisms 7, 8 for lifting and expanding or contracting the torch. The torch 3 executes the parallel fillet welding of vertical faces A, B by such mechanisms. The torch executes continuously welding by turning around the corner part by the mechanisms 5, 6, 7, 8. The automation and unattended operation of welding are thus made possible.

Description

Detailed Description of the Invention: "Industrial Field of Application J The present invention provides a method for automatically and continuously welding horizontal fillet joints forming a grid in structures such as ships. 141! I + Z to the square mesh automatic welding device
! , /71% Thick Z It is difficult to perform welding automatically. For example, when welding a part of a corner as shown in Fig. 6, the corner between the welded material A-B forming a vertical surface and the welded material C forming a horizontal surface. Most of the flesh welds can be welded automatically using a suitable welding machine, but
If it is within a range of approximately m, a portion (remaining welded portion) that cannot be welded becomes X. Therefore, it is not possible to perform square welding work continuously, and the remaining welded portion
It is necessary to perform so-called manual welding to weld the parts anew, resulting in a duplication of the welding process and problems such as uneven quality in the parts welded by the automatic welding process and the manual welding process.

"Objectives of the Invention and Means for Solving the Problems" The present invention aims at unmanned and automated welding work at various fillet joints forming squares in structures such as ships, and expands its scope of application. Then, LN
This makes it possible to apply this method to fields where automatic welding has traditionally been difficult to apply, such as the aluminum tanks of G-ships. In order to achieve that objective, the present invention includes a means for maintaining a constant distance between the welding line and the torch, and a means for maintaining a constant distance between the welding line and the torch, on a trolley that moves the torch in parallel along the straight line portion of the welding line forming the grid. It is equipped with a means for detecting the angle with the vertical plane that forms the welding line and keeping the torch angle constant relative to the direction of the welding line, and a means for changing the torch angle relative to the trolley around the arc point at the tip of the torch as the center of rotation. For the welding line, which is mainly a straight line, the torch is moved in parallel with the trolley while detecting the distance and angle between the torch and the vertical plane, and the trolley is stopped near some corners. At the same time, the torch is rotated around the arc point at the tip while keeping the angle of the torch constant with respect to the inwardly curved surface previously formed in a part of the corner, and the torch is rotated around the arc point at the tip to pass through the inwardly curved surface. Thereafter, the torch is repeatedly guided along the next straight welding line by the trolley, so that the welding work including a portion of the corner progresses continuously.

"Example" An embodiment shown in the drawings will be described below.

In this embodiment, Figures 1 to 3 show the structure of an automatic square welding device, and Figure 4 shows a case where the automatic MIG welding method is applied to a square joint of an aluminum tank in an LNG ship. , FIG. 5 shows an example of the welding work process.

The automatic square welding device 1 is mounted on a material to be welded (for example, a skin plate) C that forms a horizontal surface, and also on a vertical surface A- that forms a linear welding line that forms a square.
A trolley 2 that travels along the line H, a torch 3 that is mounted on the trolley 2 and is moved in parallel along the welding line, and the trolley 2
and various means interposed between the torch 3 and the torch 3 to provide the torch 3 with a desired function.

The various means include a turning mechanism 4 mounted on the cart 2, a front-back sliding mechanism 5 and a left-right sliding mechanism 6 supported by the turning mechanism 4, and a torch 3 supported by both sliding mechanisms 5 and 6. a torch elevating mechanism 7 that also serves as a support bracket; a torch extensible mechanism 8 that extends from the torch elevating mechanism 7 toward the welding line; a torch opposing distance sensor 9 and a torch opposing angle sensor 10 that are attached to the tip of the torch extending mechanism 8. It is configured by combining the functions of the control unit 11 and the like disposed inside the truck 2, etc.

The details of these will be explained below. The truck 2 is provided with wheels 12 that move in the longitudinal direction and wheels 13 that move in the left and right directions, and these wheels are moved back and forth by a drive motor 14 or the like according to a command from the control section 11. Or it can be rotated left and right.

The turning mechanism 4 has two turning mechanisms 5 located above it.
-6, and a drive device for turning the torch relative to the trolley 2, and data on the turning angle is detected by a rotary encoder or the like and transmitted to the control section 11.

6゛゛゛, 8k-Handle mechanism 7 and torch extension mechanism 8 also have controls for sliding, moving up and down, moving up and down, and extending and retracting them back and forth and left and right under the command of the control unit 11. It is equipped with various drive devices.

The torch expansion/contraction mechanism 8 is provided with a parallel link, a drive mechanism for changing the distance from the center of the trolley 2 to the tip of the torch 3 by changing the angle of the parallel link, and an expansion/contraction amount sensor (encoder, etc.). The configuration is as follows.

The torch facing distance sensor 9 is a non-contact type, such as an optical sensor or an ultrasonic sensor, and outputs data on the facing distance between the torch 3 and the vertical plane A-B to the control unit 11. The torch facing angle sensor lO detects the angle θ of the welding line direction of the torch 3 with respect to the vertical plane A-H by a non-contact means, as shown in the example of FIG. When the light receiving elements 10b and 10c are in the permissible range as shown in position (a), the light receiving elements 10b and 10c do not operate, and the third
As shown at position (d) in the figure, due to the bending of the welded material A forming a vertical surface (in the example of FIG. is activated, and the control section 11 that receives the signal mainly operates the turning mechanism 4. Note that a sensor for setting the opposing distance to the welded material C forming a horizontal surface is provided at the tip of the torch 3, if necessary, in accordance with the torch opposing distance sensor 9, and the position of the torch 3 is adjusted. It is also possible to set it automatically.

Further, the control section 11 is composed of a central processing unit (CPU), etc., and is used to move the torch 3 and the trolley 2, etc., and is designed to link each means with the progress of the welding work process. be. To give a supplementary explanation of each of these means, the means for keeping the distance between the welding line and the torch 3 constant is to transmit the data of the torch facing distance sensor 9 to the controller 11.
It is composed of a trolley 2, a front-rear slide mechanism 5, a left-right slide mechanism 6, a torch extension mechanism 8, etc., which are operated by transmitting a signal to the torch. Data control unit 1
It mainly consists of a turning mechanism 4 that is operated by transmitting a signal to the torch 1, and a means for keeping the distance constant, and a means for changing the torch angle around the arc point at the tip of the torch as the center of rotation. This is linked to the means for keeping the torch angle constant, but when adjusting each function to keep the opposing angle with the welded material A-B forming a vertical plane constant, the arc When performing linear welding so that the moving speed of the point is constant, for example, the moving speed of the trolley 2 is kept constant, and the front-rear slide mechanism 5, the left-right slide mechanism 6, the torch extension mechanism, etc. are moved. When necessary, the turning mechanism 4 is activated by a command from the control unit 11 so that the tip of the torch 3 moves at the moving speed of the trolley 2.
When the trolley 2 is in a stopped state, the torch is operated so that the combined movement of the rotation mechanism 4, front/rear slide mechanism 5, left/right slide mechanism 6, and torch extension/contraction mechanism 8 reaches the welding speed. By adjusting the angle,
As welding progresses, the torch 3 is moved around the arc point.

In addition, in the square joint in one embodiment, as shown in Fig. 4, the materials to be welded A and B forming vertical surfaces are transformers and stiffeners, and the materials to be welded C forming horizontal surfaces are skin plates. This is a horizontal fillet joint that is generated by arranging materials, and welding is carried out by mounting the main part of the automatic square welding device on the running surface made of the material to be welded C.

That is, when welding a grid-shaped weld line as shown by the arrow in FIG. 4, at the welding start position S, the torch 3 mounted on the trolley 2 is vertically moved The welding work is started after each means is set so as to maintain the state perpendicular to plane A. At this time, an inwardly curved surface E is formed in advance at the detection position of the torch facing angle sensor 10 at the corner by processing a welded portion or attaching a member having a similar shape. The inward curved surface E is
When the seam of the vertical plane A-H is formed by welding and finishing, the weld line formed by the material to be welded C forming the horizontal plane and 1. Torch facing angle sensor 1
If the inward curved surface E is constructed by pasting a material with a curvature that matches the detection point of 0, for example, 5 to 8 + m
degree.

In addition, in the turning mechanism 4, the torch facing angle sensor 1
The welding operation proceeds while the torch 3 is moved in parallel by the trolley 2 so that the left and right slide mechanism 6 holds the torch 3 at approximately the center position on the left and right sides by the torch opposing distance sensor 9. In this welding process, the position between the welding line at the bottom of the vertical plane A and the tip of the torch 3 is detected by the torch facing distance sensor 9 and the torch facing angle sensor 10, and the left and right sliding mechanism 6 and is corrected via the turning mechanism 4.

Next, when the cart 2 approaches another vertical surface B and detects this, or is stopped by a stopper such as the vertical surface B, the state shown in FIG. 5(B) is reached. In this case, with the trolley 2 stopped, the front and rear slide mechanism 5 is operated to move the torch 3 forward with respect to the trolley 2, and the left and right switch W/VM11! I Q Tl, re
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1c, guide the torch 3 around the corner while keeping the position of the arc point at the tip of the torch 3 constant, and detect the angle with respect to the inward curved surface E with the torch facing angle sensor 10,
The torch extension/contraction mechanism 8 is extended and the left/right slide mechanism 6 is moved to the left.
The torch 3 is rotated to the right by the turning mechanism 4, and the trolley 2 is moved backward as necessary.
The state shown in FIG. 5(C) is led to the state shown in FIG. 5(D).

The welding operation to the right from the position of the torch 3 in FIG. 5(D) is performed by switching to the left-right moving wheels 13 in order to move the cart 2 to the right, as shown in FIG. 5(A). The process continues with the torch 3 in an extended state according to the state of the torch 3.

Furthermore, while extending and contracting the torch 3 at each corner and rotating the torch 3 around the arc point, the welding work is automatically progressed as shown by the arrow in Fig. It will continue until S.

In addition, in one embodiment, the trolley 4 has wheels 12 that move in the longitudinal direction.
Although it is assumed that the vehicle is moved back and forth and left and right on the running surface 1 by the left and right moving wheels 13, it is of course possible to move while being guided along a rail or the like. Further, the torch angle is not limited to being perpendicular to the direction of the welding line, but may be any angle that is maintained at a constant angle within a range close to perpendicular. Furthermore, it goes without saying that it can also be used in cases where the vertical surfaces A and B are curved with respect to the direction of the welding line.

[Effects of the Invention J As explained above, according to the present invention, the following effects can be achieved.

■Since the torch is rotated around the arc point at the tip while keeping the angle of the torch constant at corners, etc., just by forming an inwardly curved surface at the corner,
The welding operation between two mutually orthogonal straight parts and the corner between them can be performed continuously.

■Through the above, we aim to unmanned and automate welding work at various fillet joints that form squares in structures such as ships, and expand the scope of its application.
It can also be applied to fields where automatic welding has traditionally been difficult to apply, such as aluminum tanks for LNG ships.

■Since the torch angle is adjusted by rotating the torch around the arc point, accurate welding work can be performed without the torch tip moving.

[Brief explanation of drawings]

1 to 5 show an embodiment of the automatic square welding device of the present invention, in which FIG. 1 is a side view, FIG. 2 is a plan view,
FIG. 3 is an explanatory diagram of the operation of the angle sensor, and FIG. 4 is a perspective view showing an example of a square joint welded by an automatic square welding device.
5(A) to 5(D) are process explanatory views of the welding work of the welded joint shown in FIG. 4, and FIG. 6 is a perspective view of essential parts illustrating an example of welding a part of a corner according to the prior art. Q.
,, Kaichu'l,,, ,,, Torch, 4...
...Swivel mechanism, 5... Front and rear slide mechanism, 6.
...Right and left slide mechanism, 7...Torch lifting mechanism, 8...Torch extension and contraction mechanism, 9...
・Torch facing distance sensor, 10...Torch facing angle sensor, 11...Control unit, 12...
- Forward and backward moving wheels, 13... Lateral moving wheels, 14... Drive motor, A... Material to be welded, B... Material to be welded, C: Material to be welded, D: Corner, E: Inward curved surface Fig. 4 Fig. 5 Fig. 5

Claims (1)

[Claims] A dolly that moves the torch in parallel along the straight line of the welding line forming a grid is equipped with a means for keeping the distance between the welding line and the torch constant, and a means for detecting the angle between the vertical plane forming the welding line and determining the torch angle. A square mesh automatic welding device, characterized in that it is equipped with means for maintaining the welding line in a constant state with respect to the direction of the welding line, and means for changing the angle of the torch with respect to the trolley around the arc point at the tip of the torch as the center of rotation.