JPH0592268A - Twin arc welding method by arc welding robot - Google Patents

Abstract

PURPOSE:To perform twin-arc welding without control software by subjecting two articulated arc welding robots provided on a common external control axis movable in the weld line direction to make arc sensor profile control. CONSTITUTION:The two articulated arc welding robots 16 are fitted to the common external control axis 12 movable in the weld line direction, at the time of main welding excepting the welding starting and finishing time, the respective welding robots are subjected to arc sensor profile control by a high speed rotating arc welding method while these are stopped in the weld line direction and welding is performed while the external control axis 12 is moved along the weld line direction. Consequently, the manufacturing cost of welding equipment is reduced and twin arc welding can be performed without requiring the software for synchronous control.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a pair of fillet welded joints for shipbuilding and bridge panels, and two multi-joint arc welding robots and a common external synchronous control shaft for simultaneously welding both sides under the same welding conditions. The present invention relates to a twin arc welding method.

[0002]

2. Description of the Related Art For example, when a pair of fillet welded joints for shipbuilding or bridge panels are welded under the same welding conditions (this is called twin arc welding), two articulated robots are used. A method has been adopted in which each articulated robot is used as one set and has an external control axis that independently moves on each fillet weld joint, and performs welding in synchronization with each fillet weld joint. ..

[0003]

However, since such a method does not have a common external control axis, two sets of external control axes are required, resulting in high manufacturing cost, and each articulated robot requires its own control software. It was difficult to perform welding in synchronism to perform welding, and in the end it was no different from moving one robot twice.

The present invention has been made in order to solve the above problems, and in the case of performing twin arc welding, the manufacturing cost of the welding device is low, and no troublesome control software for synchronous control is required. An object is to provide a twin arc welding method by an arc welding robot.

[0005]

A twin arc welding method by an arc welding robot according to the present invention is a method in which two articulated arc welding robots are attached to a common external control shaft that is movable in the welding line direction, and a pair of corners are provided. At the start of welding and at the end of welding for meat welded joints, the external control axis is stopped and each articulated arc welding robot is driven and controlled by each robot controller to perform welding, except at the start and end of welding. At the time of main welding, the multi-joint arc welding robot is stopped in the welding line direction, and the arc sensor copying control is performed in the plane perpendicular to the welding progress direction by the high-speed rotating arc welding method, and the external control axis is set in the welding line direction. Twin arc welding is performed while moving along.

[0006]

According to the present invention, the multi-joint arc welding robot is stopped in the direction of the welding line during the main welding except at the start of welding and at the end of welding, and the plane is perpendicular to the welding proceeding direction by the high-speed rotating arc welding method. By performing the arc sensor copying control with the two external articulated arc welding robots, twin arc welding is performed while moving the common external control axis along the welding line direction. In the case of main welding of joints, each articulated arc welding robot does not need to perform synchronous control because it performs only arc sensor scanning control, and does not require control software for performing synchronous control. Further, since the external control axis is one in common, the manufacturing cost of the welding device including the articulated arc welding robot with two sets as one set is low.

[0007]

1 is a sectional view showing a state in which the method of the present invention is being carried out, and FIG. 2 is a perspective view showing a state in which the method of the present invention is being carried out. In the figure, 1 is a lower plate, 2 is a standing plate that is erected on the lower plate 1, and 3 is a pair of fillet weld joints formed by the lower plate 1 and the standing plate 2. Reference numeral 10 denotes a gate-shaped control shaft support frame that is laid over the lower plate 1, 11 is a guide rail provided on the upper surface of the horizontal frame of the control shaft support frame 1,
Reference numeral 2 denotes an external control shaft which moves on the horizontal frame of the control shaft support frame 10 in the lengthwise direction thereof while being guided by the guide rails 11, 13 denotes a rotating roller provided at the center of the external control shaft 12, and 14 denotes external control. A moving motor provided on the upper surface of the central portion of the shaft 12, 15 is a drive roller that is connected to the moving motor 14 and drives the rotating roller 13, and 16 is a 6-axis motor mounted on the lower surfaces of both ends of the external control shaft 12. A multi-joint arc welding robot, 17 is a hand of the multi-joint arc welding robot 16, and 18 is a welding torch attached to the hand 17, which is rotated at a high speed by a motor 19. 20 is a welding wire. Further, the groove tracking control of the welding torch 18 by the arc sensor can be performed by the articulated shaft of the robot.

Next, the method of the present invention will be described.

First, at the start of welding in which welding is performed on the starting end portion of the standing plate 2 erected on the lower plate 1, the welding torch 18 starts to move after detecting the arc generation by the welding current or arc voltage. In the articulated arc welding robot 16 having two start timings of the movement of the welding torch 18,
There is a slight deviation at 16. Therefore, the external control axis 1
2 is stopped at the starting end portion position of the standing plate, and each articulated arc welding robot 16 is drive-controlled by each robot controller to start welding independently.

If the two articulated arc welding robots 16 and 16 confirm the arc generation and start moving the welding torch 18, that is, if welding is started, each articulated arc welding robot 16 is attached. With the welding torch 16 being stopped in the welding direction, the articulated arc welding robot 16 performs arc sensor scanning control on the welding torch 16 by a high-speed rotary arc welding method in a plane perpendicular to the welding proceeding direction. External control axis 1
Twin arc welding is performed on the pair of fillet weld joints 3 by moving 2 along the welding line direction. The movement of the external control shaft 12 is performed by rotating the moving motor 14 and rotating the rotating roller 13 via the drive roller 15 so that the control shaft supporting frame 10 travels on the horizontal frame in the length direction thereof. .. At this time, since the external control shaft 12 having the two articulated arc welding robots 16 moves, the welding speeds of the two welding torches 16 become the same, and
It becomes possible to perform the synchronous control welding by the external control shaft 12 common to the multi-joint arc welding robot 16 of the table.

When welding progresses by such twin arc welding and each welding torch 16 reaches near the end of the standing plate 2,
The twin-arc welding is stopped by stopping the movement of the external control shaft 12 at a predetermined distance before the end of the standing plate 2, for example, 10 mm immediately before the end. The reason why the external control shaft 12 is stopped before the end of the standing plate 2 is that there is a deviation in the welding length at the start of welding. At the end of welding after that, the external control shaft 12
Each articulated arc welding robot 1 with the robot stopped
6 is driven and controlled by each robot controller, and the remaining welding is performed independently. The remaining weld length is determined by the following formula.

[Remaining welding length] = [Teached total welding length]-[Welding length at arc start]-[Amount of movement of external control axis in welding direction] Thus, a pair of fillet weld joints When performing the main welding on most of 3 and 3, the two articulated arc welding robots 16 and 16 provided at both ends of the common external control shaft 12 that moves in the welding direction perform only arc sensor scanning control. In order to do so, it is not necessary to perform synchronous control. Therefore, twin arc welding can be performed without requiring control software for performing synchronous control on the two articulated arc welding robots 16, 16. Further, since the external control shaft 12 is one in common, the manufacturing cost of the welding device including the two articulated arc welding robots 16 and 16 can be reduced.

Although the external control shaft 12 of this embodiment moves in the uniaxial direction of the x axis, for example, the external control shaft 12 which moves in the biaxial directions of the x and y axes can be applied to a curved welding line. , Y, z axes that move in three axial directions can be applied to a spiral welding line.

Further, in this embodiment, the pair of fillet welded joints 3 formed by the lower plate 1 and the upright plate 2 is used, but it goes without saying that it is also applicable to a lap joint and a butt joint having a groove. ..

[0015]

As described above, according to the present invention, at the time of main welding except at the start of welding and at the end of welding, each articulated arc welding robot is stopped in the welding line direction by the high-speed rotating arc welding method. Since the arc sensor copying control is performed in a plane perpendicular to and twin twin welding is performed while moving a common external control axis equipped with two articulated arc welding robots along the welding line direction,
In the case of main welding of a pair of fillet welded joints, each articulated arc welding robot does not need to perform synchronous control because it performs only arc sensor scanning control, and requires control software for performing synchronous control. In addition, since there is only one external control axis in common, there is an effect that the manufacturing cost of the welding device composed of two sets of articulated arc welding robots can be reduced.

Further, since the welding of the pair of fillet weld joints at the start and the end of welding is separately performed by using the robot controller of each articulated arc welding robot, synchronous control is not necessary. The effect is that welding can be easily performed if it is placed after teaching.

[Brief description of drawings]

FIG. 1 is a sectional view showing a state in which a method of the present invention is being carried out.

FIG. 2 is a perspective view showing a state in which the method of the present invention is being carried out.

[Explanation of symbols]

 3 Fillet Weld Joint 12 External Control Axis 16 Articulated Arc Welding Robot 18 Welding Torch

Claims (1)

[Claims] 1. Two articulated arc welding robots are attached to a common external control axis that can move in the welding line direction, and the external control axis is set for a pair of fillet weld joints at the start and end of welding. After stopping, each articulated arc welding robot is driven and controlled by each robot controller to perform welding, and each articulated arc welding robot is stopped in the welding line direction during the main welding except at the start of welding and at the end of welding. An arc characterized in that twin arc welding is performed by moving the external control axis along the welding line direction by performing arc sensor copying control in the plane perpendicular to the welding proceeding direction by the high speed rotating arc welding method. Twin arc welding method by welding robot.