JPH0538576A - Method and device for retrying generation of arc in automatic welding device - Google Patents

Abstract

PURPOSE:To provide a method and a device for retrying the generation of the arc in an automatic welding device which can avoid automatically an arc start failure, even in the case the arc start failure is generated at the time of reignition by slag on the surface of the front layer bead. CONSTITUTION:The device is provided with a slag deciding means 18 for deciding that slag is generated in a welding starting point on the front layer bead in the lower part of a torch 3, in the case a starting command is issued and also an arc is not generated even of a prescribed time elapses, and also, provided with a slag avoidance control means 22 for moving the torch 3 by a prescribed amount in an upper direction, thereafter, moving it to any one of both end parts of groove oscillation width, in the case slag is detected, and by avoiding automatically the slag, the arc can be generated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to multi-layer welding by automatic welding equipment such as robot welding using gas shield metal arc welding, in which a non-conductive slag is formed on the arc extinguishing portion of the welding arc on the front bead surface. The present invention relates to an arc generation retry method for automatic welding equipment and its equipment that can automatically avoid solidification, which results in arc start failure when current does not flow during re-ignition for forming the next layer. is there.

[0002]

2. Description of the Related Art In a well-known arc sensor having a groove automatic copying control function, in an automatic welding apparatus using gas shield metal arc welding, for example, robot welding, arc extinction and re-ignition of a welding arc are repeated many times. The position of the electrode wire when the welding arc is extinguished or when re-ignition is started is controlled by the arc sensor to be located at the center in the groove width direction.

In such robot welding, particularly when performing multi-pass welding, when non-conductive slag is solidified in the arc extinguishing part of the welding bead on the front bead surface, when re-ignition for forming the next layer, Electrode wire is fed on this slug,
The current may not flow, resulting in an arc start failure.

In such a case, conventionally, an operator removes the slag or moves the robot to change the torch position.

As described above, in the case of an arc start failure, it is conventionally necessary to manually take measures for avoiding the slag, so that if a start command is issued, the apparatus or program is constructed so that the arc always occurs first. This is because it has been done.

[0006]

As described above, since the conventional arc generation retry method of the automatic welding apparatus is performed manually, the operation rate of the robot is deteriorated or the unmanned operation is unattended due to the arc start failure. There was a problem that it could not be achieved.

In view of the above points, the present invention is an arc welding retry method for an automatic welding apparatus, which is capable of automatically avoiding an arc start failure during re-ignition due to the slag on the front bead surface. And its device.

[0008]

According to a first aspect of the present invention, there is provided a method for retrying arc generation in an automatic welding apparatus, wherein a consumable electrode wire is provided by an automatic welding apparatus having a groove automatic scanning control function by a swinging arc sensor. After forming a bead of a predetermined height in the groove to the end of the groove line using, the arc is extinguished, the torch holding the wire is raised to the next layer position and waits for a predetermined bead cooling time. After step 1 and a predetermined bead cooling time, if no arc is generated for a predetermined time after starting wire feeding and welding power source output by the start command, on the front layer bead below the torch The second step of determining that slag is occurring at the welding start point of No., and if it is determined that slag is occurring, stop the wire feeding and the output of the welding power source and raise the torch by a predetermined amount. After letting it Is moved to swing width side ends of the layer,
In the third step of performing the arc start, and when the arc is not ignited even in the third step, the wire feeding and the output of the welding power source are stopped again, the torch is raised by a predetermined amount, and then the layer is rocked. It is characterized by having a fourth step of moving to the other end of the width and performing a re-arc start.

Further, in the arc generation retry method for the automatic welding device according to the second aspect of the present invention, the groove is automatically formed by using the consumable electrode wire by the automatic welding device having the groove automatic copying control function by the rotary arc sensor. After forming a bead of a predetermined height to the groove line end, extinguishing the arc, raising the torch holding the wire to the next layer position and waiting for a predetermined bead cooling time, After the predetermined bead cooling time, if no arc is generated even after a lapse of a predetermined time from the start of wire feeding and welding power output by the start command, at the welding start point on the front bead below the torch. A second step of determining that slag is occurring,
If it is determined that slag is occurring, stop the wire feeding and welding power output, rotate the torch, and then
And a third step of performing an arc start.

Further, the arc generation retry device of the automatic welding device according to the third aspect of the present invention is provided with a groove automatic tracing control function by a swinging arc sensor, and multi-layer welding is performed for each layer by a consumable electrode wire. In the automatic welding apparatus that performs the cooling time, if there is a start command and no arc is generated even after the lapse of a predetermined time, the slag is placed at the welding start point on the front bead below the torch holding the wire. Slag determining means for determining that the slag is occurring, and if the slag determining means determines that slag is occurring, the slag avoidance commanding means for stopping the wire feeding and the output of the welding power source, and the slag. When the determination means detects the slag and has an X- and Y-axis start command, the Y-axis motor drive unit is instructed to move the torch upward by a predetermined amount, and the first X-axis movement is performed. When a signal or a second X-axis movement signal is input, a first slag avoiding means that issues an instruction to start arc generation, and a movement instruction in the Y-axis upward direction is output from the first slug avoiding means. And the first X-axis movement amount to the one end of the swing width obtained from the X-axis position in the groove width direction at that time and the preset swing width. A second slug avoiding means for outputting a first X-axis movement signal to the first slag avoiding means, while instructing the portion to move the torch to the swing width piece side end of the X axis. When the slag determining means determines that the slag is generated after the second slag avoiding means outputs the first X-axis movement signal, it is determined from the preset swing width, A second X-axis movement amount in a direction opposite to the direction of the first X-axis movement amount Then, the X-axis motor drive unit is instructed to move the torch to the other end of the swing width of the X-axis, and the second X-axis movement signal is output to the first slag avoiding means. A third slag avoiding means is provided.

Further, the arc generation retry device of the automatic welding device according to the fourth aspect of the present invention has a groove automatic copying control function by a rotary arc sensor, and multi-layer welding is performed for each layer by a consumable electrode wire. In an automatic welding device that performs cooling time, if there is a start command and arc does not occur even if a predetermined time has elapsed, slag is generated at the welding start point on the front layer bead below the torch holding the wire. A slag determining means for determining that the slag is occurring, a slag avoidance commanding means for stopping the wire feeding and the output of the welding power source when the slag is determined by the slag determining means, and the slag determination When the means detects the slag and there is a torch rotation start command, the torch rotation drive unit is instructed to rotate the torch, and the torch has rotated. In which the input of the signal indicating the provided and slag avoidance control means for a command to start the arcing if.

[0012]

In the present invention, even if an arc start failure occurs during re-ignition due to the slag on the surface of the front layer bead, the slag determination means detects this slag, and based on this, the slag avoidance control means moves up the torch. After a predetermined amount of movement in the direction, the groove is moved to either end of the swing width, or the torch is rotated to automatically avoid the slag, and an arc can be generated.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An arc welding retry method for an automatic welding apparatus according to an embodiment of the present invention and an apparatus used for this method will be described below with reference to FIGS. FIG. 1 shows an application of the present invention to an orbiting arc welding robot which has a groove automatic copying control function by an orbiting arc sensor and performs multi-layer welding with a consumable electrode wire while keeping a predetermined cooling time for each layer. FIG. 2 is a block diagram showing a circuit configuration of an arc generation retry device, FIG. 2 is a block diagram showing a detailed circuit configuration of an essential part thereof, and FIGS. 3 to 6 are process diagrams for explaining an arc generation retry method using this device. Is.

In FIG. 1, 1 and 2 are base materials, 3 is a torch arranged opposite to the V-shaped groove of the base materials 1 and 2, and 4 is a consumable electrode wire held by the torch 3. This wire 4
Is supplied with a DC constant voltage power supply or a DC constant current power supply from the power supply unit 6 while being fed at a constant speed by the feed motor 5, and blows a welding arc so as to maintain a predetermined arc current or arc voltage.

The torch 3 is gear-coupled to a feed screw 8 of an X-axis block 7 horizontally attached to the robot tip,
The X-axis motor 9 moves the feed screw 8 horizontally (X-axis ± direction).

The X-axis block 7 is gear-coupled to the feed screw 11 of the Y-axis block 10 which is vertically attached to the tip of the robot, and is moved vertically (Y-axis ± direction) along the feed screw 11 by the Y-axis motor 12. To do.

Reference numeral 13 is an arc detecting means, which detects an arc current or an arc voltage of a DC constant voltage power supply or a DC constant current power supply from the power supply unit 6 and, if an arc is generated, a swinging arc described later. The arc detection signal is output to the control device and the slag determination means, and the output is stopped if no arc is generated.

Reference numeral 14 is an oscillating arc control device having a groove automatic copying control function by a known oscillating arc sensor.
When the start command is issued, the power supply unit 6, the wire feeding motor drive unit 15, the X-axis motor drive unit 16, and the Y-axis motor drive unit 17 are turned on, whereby the arc detection signal from the arc detection unit 13 is generated. Is input, the wire feed motor drive unit 1 is based on this arc detection signal.
5, X-axis motor drive unit 16, and Y-axis motor drive unit 17
Is controlled to generate a swinging arc. Further, when there is a start command, the welding power source is turned on, and the wire feeding is started, and then the slag detection signal is input, the slag avoidance command unit 14a causes the welding power source and the wire feeding motor driving unit 15 to operate. When the standby instruction signal is input, the welding power source and the wire feeding motor drive unit 15 are returned to the ON state again. Reference numeral 18 is a slag determining means, and if there is a start command and there is no arc detection signal input from the arc detecting means 13 even after a lapse of a predetermined time, the wire 4 causes slag at the welding start point on the front layer bead. It is determined that the slag detection signal is output to the swing arc control device 14, the slag avoidance control means, the Y-axis movement amount calculation means, the X-axis movement amount calculation means, and the X-axis movement amount reading means, which will be described later. It is a thing.

Reference numeral 19 denotes a Y-axis movement amount calculating means, which receives the slag detection signal from the slag determining means 18 and calculates the next layer from the current Y-axis position of the torch 3 and preset layer data. The Y-axis movement amount of the torch 3 up to is calculated, and the calculated Y-axis movement amount is output to the first slag avoiding means and the Y-axis movement end determining means, which will be described later.

Reference numeral 20 denotes an X-axis movement amount calculating means, which is preset with the current X-axis position of the torch 3 (center position of the V-shaped groove line) when the slag detection signal is inputted from the slag determining means 18. From the swing width data W in that layer,
The first X-axis movement amount W / of the torch 3 up to the end of the swing width side
2 is calculated, and the calculated first X-axis movement amount W / 2 is output to the second slag avoiding means and the X-axis movement end determining means, which will be described later.

Reference numeral 21 is an X-axis movement amount reading means, and when the slag detection signal is input from the slag determining means 18, the swing width data W of the torch 3 in that layer which has been preset is read and read. Set the swing width W of the torch 3 to the second X
The axial movement amount W is set, and the second X-axis movement amount W is output to the third slag avoiding means and the X-axis movement end determining means, which will be described later, respectively.

Reference numeral 22 is a slag avoiding control means, which is composed of a first slag avoiding means 22a, a second slag avoiding means 22b, and a third slag avoiding means 22c, as shown in FIG. When the slag detection signal from the slag determination means 18 and the X and Y axis start command or the X and Y axis restart command are input, the Y axis movement amount and the X axis movement from the Y axis movement amount calculation means 19. First from quantity calculating means 20
X-axis movement amount W / 2 or the second X-axis movement amount W from the X-axis movement amount reading means 21.
6 and the Y-axis motor drive unit 17 are instructed to perform the slag avoiding operation of the torch 3.

That is, the first slag avoiding means 22a
Is a slag detection signal from the slag determination means 18 and X, Y
When the axis start command is issued, the Y-axis motor drive unit 17 is instructed to move the torch 3 to the next-layer position in the Y-axis-direction based on the Y-axis move amount from the Y-axis move amount calculating means 19. When the first X-axis movement signal from the second slag avoiding means 22b or the second X-axis movement signal from the third slag avoiding means 22c is input, the standby instruction means described later , And gives a command to start arc generation.

When the second slag avoiding means 22b outputs a movement command in the Y-axis negative direction from the first slag avoiding means 22a, the first X-axis moving amount calculating means 20 outputs the first X-axis. Based on the moving amount W / 2, the X-axis motor drive unit 16 is instructed to move the torch 3 to the end of the swing width piece in the X-axis-direction, and at the same time, the first slag avoiding means 22a.
To output a first X-axis movement signal to the.

The third slag avoiding means 22c is used when the slag determining means 18 determines that a slag is occurring after the second slag avoiding means 22b outputs the first X-axis movement signal. , Second from the X-axis movement amount reading means 21
On the basis of the X-axis movement amount W of X, the X-axis motor drive unit 16 is instructed to move the torch 3 to the other end of the swing width in the X-axis + direction, and the first slag avoiding means 22a is instructed. It outputs two X-axis movement signals.

Reference numeral 23 is a Y-axis movement end determination means, which is used when the slag avoidance control means 22 is in operation.
The Y-axis movement amount from 9 and the output from the Y-axis motor drive unit 17 are compared, and if the difference becomes zero, it is determined that the Y-axis movement has ended, and the slag avoidance control means 22 is controlled to Y. It outputs an axis movement end signal.

Reference numeral 24 is an X-axis movement end determining means, which is used when the slag avoidance control means 22 is operating.
The first X-axis movement amount W / 2 from 0 or the second X-axis movement amount W from the X-axis movement amount reading means 21 and the output from the X-axis motor drive unit 16 are compared, and the difference is obtained. If becomes zero, X
It is determined that the axis movement has ended, and an X-axis movement end signal is output to the slag avoidance control means 22.

Reference numeral 25 denotes a standby instruction means, which issues a standby instruction signal to the rocking arc control device 14 when the first slag avoidance means 22a of the slag avoidance control means 22 gives an instruction to start arc generation. Is.

Next, an arc generation retry method using the embodiment apparatus having the above-mentioned structure will be described with reference to FIGS. 3 to 6.

First, by means of an orbiting arc welding robot equipped with a groove automatic tracing control function by an orbiting arc sensor, a bead of a predetermined height is placed in the V-shaped groove of the base materials 1 and 2 by using the consumable electrode wire 4. After forming b (first layer) to the end of the groove line, the arc is extinguished at the central position of the V-shaped groove line, and the torch 3 is raised to the position of the next layer (second layer) to perform predetermined bead cooling. Wait for a time (Fig. 3).

Next, after a predetermined bead cooling time, the welding power supply is turned on by the start command, and the feeding of the wire 4 is started. If no arc is generated even after a lapse of a predetermined time from the start of feeding the wire 4, it is determined that the slag s is generated at the welding start point on the first layer bead b below the torch (Fig. 4). ), Stop the wire feeding and welding power output.

Next, after the torch 3 is further raised to the position of the next layer (third layer), the torch 3 is moved by W / 2 to one end of the swing width W of the second layer to start arcing (FIG. 5). ). At this time, the torch 3 is in the third layer position, but if there is a start command, the torch 3 is automatically lowered to the set second layer position and then the feeding of the wire 4 is started.

When the arc is not ignited at the end of the swing width piece (FIG. 5), the wire feeding and the output of the welding power source are stopped again, the torch 3 is raised again to the third layer position, and then the Two
The W is moved to the other end of the swing width of the layer to start the arc (Fig. 6).

7 to 10 show an arc generation retry method for an automatic welding apparatus according to another embodiment of the present invention and an apparatus used for this method. FIG. 7 shows an automatic groove preparation using a rotary arc sensor. The present invention is applied to a rotary arc welding robot having a copy control function and performing multi-layer welding with a consumable electrode wire while keeping a predetermined cooling time for each layer, and is a block diagram showing a circuit configuration of an arc generation retry device. 8 to 10 are process drawings for explaining an arc generation retry method using this apparatus. In each figure, parts corresponding to those in FIGS. 1 to 6 are designated by the same reference numerals. In FIG. 7, reference numeral 30 is an arm whose base end is gear-coupled to a feed screw 11 of a Y-axis block 10 which is vertically attached to the robot tip and which rotatably supports a torch 3 at the tip. 12 moves vertically (Y axis ± direction) along the feed screw 11.

The Y-axis block 10 is gear-coupled to the feed screw 8 of the X-axis block 7 horizontally attached to the tip of the robot, and is moved horizontally (X-axis ± direction) along the feed screw 8 by the X-axis motor 9. To do.

The torch 3 is connected to the output shaft of a torch rotation motor 31 attached to the arm 30 via gears 32 and 33, and is rotated by the torch rotation motor 31. The consumable electrode wire 4 penetrates the torch 3 in an oblique direction, and the projecting ends of the consumable electrode wire 4 can be aimed at the corners at both ends of the narrow groove widths of the base materials 1 and 2.
Reference numeral 34 is a rotary arc control device having a groove automatic copying control function by a known rotary arc sensor. When a start command is issued, the power supply unit 6 and the wire feeding motor drive unit 1 are provided.
5, the X-axis motor drive unit 16, the Y-axis motor drive unit 17, and the torch rotation drive unit 35 are turned on, and when an arc detection signal is input from the arc detection unit 13 by this, this arc detection signal Based on the above, the wire feed motor drive unit 15 and the torch rotation drive unit 35 are controlled to generate a rotary arc, and when moving in the groove line direction,
The X-axis motor drive unit 16 and the Y-axis motor drive unit 17 cause the operation by the groove line automatic copying control. When a slag detection signal is input from the slag determination means 18 after a start command is issued, the welding power source is turned on, and wire feeding is started, the slag avoidance command unit 34
When the welding power source and the wire feed motor drive unit 15 are turned off, and when a standby instruction signal is input from the standby instruction unit 25, the welding power source and the wire feed motor drive unit 15 are turned back on. is there.

Reference numeral 36 is a slag avoiding control means, and when the slag determination means 18 detects the slag and receives a torch rotation start command, the torch 3 is sent to the torch rotation drive section 35.
When a torch rotation signal for notifying that the torch 3 has rotated is input, the standby instruction means 25 is instructed to start arc generation.

Reference numeral 37 denotes a torch rotation determining means, which determines that the torch 3 has rotated if there is an output from the torch rotation driving section 35 when the slag avoiding control means 36 is operating, and instructs the slag avoiding control means 36. It outputs a torch rotation signal.

Next, an arc generation retry method using this apparatus will be described with reference to FIGS. 8 to 10.

First, by a rotary arc welding robot equipped with a groove automatic copying control function by a rotary arc sensor, a bead b (a first b) of a predetermined height is provided in a narrow groove of the base materials 1 and 2 by using a consumable electrode wire 4. 1 layer) up to the end of the groove line,
The arc is extinguished at the center position of the narrow groove, the torch 3 is lifted to the next layer (second layer) position, and the bead cooling time is waited for a predetermined bead cooling time (FIG. 8).

Next, after a predetermined bead cooling time, the welding power supply is turned on by the start command, and the feeding of the wire 4 is started. If no arc is generated even after a lapse of a predetermined time from the start of feeding the wire 4, it is determined that the slag s is generated at the welding start point on the first layer bead b below the torch (Fig. 9). ), Stop the wire feeding and welding power output.

Next, the torch 3 is rotated, and if the torch 3 rotates, arc start is performed (FIG. 10).

[0043]

As described above, according to the present invention, even if the arc start failure occurs during re-ignition due to the slag on the surface of the front bead, this slag is detected by the slag determination means, and based on this, Since the torch is moved upward by a predetermined amount by the slag avoidance control means and then is moved to either of the both ends of the groove swing width, or the torch is rotated, this can be automatically avoided. Therefore, it is possible to improve the operation rate of the automatic welding apparatus, and there is an effect that unmanned operation can be achieved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a circuit configuration of an arc generation retry device of an automatic welding device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a detailed circuit configuration of a main part of an arc generation retry device of an automatic welding device according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram for explaining a first step of the arc generation retry method of the automatic welding device according to the embodiment of the present invention.

FIG. 4 is an explanatory diagram for explaining a second step of the arc generation retry method for the automatic welding device according to the embodiment of the present invention.

FIG. 5 is an explanatory diagram for explaining a third step of the arc generation retry method of the automatic welding device according to the embodiment of the present invention.

FIG. 6 is an explanatory diagram for explaining a fourth step of the arc generation retry method for the automatic welding device according to the embodiment of the present invention.

FIG. 7 is a block diagram showing a circuit configuration of an arc generation retry device of an automatic welding device according to another embodiment of the present invention.

FIG. 8 is an explanatory diagram for explaining a first step of an arc generation retry method for an automatic welding device according to another embodiment of the present invention.

FIG. 9 is an explanatory diagram for explaining a second step of the arc generation retry method of the automatic welding device according to another embodiment of the present invention.

FIG. 10 is an explanatory diagram for explaining a third step of the arc generation retry method of the automatic welding device according to another embodiment of the present invention.

[Explanation of symbols]

 3 Torch 4 Consumable Electrode Wire 14 Oscillating Arc Control Device 14a, 34a Slag Avoidance Command Unit 15 Wire Feed Motor Drive Unit 16 X-Axis Motor Drive Unit 17 Y-Axis Motor Drive Unit 18 Slag Judgment Means 22, 36 Slag Avoidance Control Means 22a First slag avoiding means 22b Second slag avoiding means 22c Third slag avoiding means 34 Rotating arc control device 35 Torch rotation driving part b Bead s Slag

Claims (4)

[Claims] 1. An automatic welding device having a groove automatic tracing control function using an oscillating arc sensor is used to form a bead having a predetermined height in the groove to the end of the groove line by using a consumable electrode wire, and then the arc is formed. The first step of extinguishing the wire, raising the torch holding the wire to the next layer position and waiting for a predetermined bead cooling time, and after the predetermined bead cooling time, feed the wire and start the welding power source by the start command. If no arc is generated after a lapse of a predetermined time from the start of output, it is determined that slag is generated at the welding start point on the front layer bead below the torch.
If it is determined that slag is occurring in the process of step 1, stop the wire feed and the output of the welding power source, raise the torch by a predetermined amount, and then move it to the end of the swing width piece of the layer. , The third step of starting the arc, and if the arc does not ignite even in the third step, the wire feed and the output of the welding power source are stopped again, and the torch is raised by a predetermined amount, and then the layer is shaken. An arc generation retry method for an automatic welding device, which comprises a fourth step of moving to the other end on the other side of the moving range and restarting the arc. 2. An automatic welding apparatus having a groove automatic copying control function using a rotary arc sensor is used to form a bead of a predetermined height in the groove to the end of the groove line by using a consumable electrode wire, and then an arc is formed. The first step of extinguishing the arc, raising the torch holding the wire to the position of the next layer, and waiting for a predetermined bead cooling time, and feeding the wire and outputting the welding power source by a start command after the predetermined bead cooling time If no arc is generated within a predetermined time after starting the welding, it is determined that slag is generated at the welding start point on the front layer bead below the torch.
If it is determined that the process of slag is occurring and the wire feed and the output of the welding power source are stopped and the torch is rotated,
And a third step of performing an arc start, a method of retrying arc generation in an automatic welding apparatus, the method comprising: 3. An automatic welding apparatus equipped with a groove automatic scanning control function by an oscillating arc sensor, and performing multi-layer welding with a consumable electrode wire while keeping a predetermined cooling time for each layer, has a start command and a predetermined time. If no arc is generated even after the lapse of time, slag determining means for determining that slag is generated at the welding start point on the front layer bead below the torch holding the wire, and slag determining means for determining the slag. If it is determined that the slag avoidance command means stops the wire feeding and the output of the welding power source, and the slag determination means detects the slag and the X and Y axis start commands are issued, Y A finger for instructing the shaft motor drive unit to move the torch upward by a predetermined amount, and for starting arcing when the first X-axis movement signal or the second X-axis movement signal is input. When the first slag avoiding means that gives an instruction and the movement command in the Y-axis upward direction are output from the first slag avoiding means, the X-axis position in the groove width direction at that time is preset. The torch is moved to the end of the swing width piece of the X-axis by the X-axis motor drive unit based on the first X-axis movement amount to the end of the swing width piece obtained from the swing width. A second slug avoiding means for issuing a command and outputting a first X-axis movement signal to the first slag avoiding means, and after the second slag avoiding means outputs a first X-axis movement signal. When the slag determining means determines that the slag is generated, the second X direction, which is the direction opposite to the first X-axis movement amount, which is obtained from the preset swing width, is obtained. Based on the axial movement amount, the torch is set to the other end of the X-axis swing width with respect to the X-axis motor drive unit. As well as a command to moving arcing retry apparatus of the automatic welding apparatus, characterized in that a third slug avoidance means for outputting a second X-axis moving signal to said first slug avoiding means. 4. An automatic welding apparatus having a groove automatic copying control function by a rotary arc sensor and performing multi-layer welding with a consumable electrode wire while keeping a predetermined cooling time for each layer. Even if no arc is generated, slag determining means for determining that slag is generated at the welding start point on the front layer bead below the torch holding the wire, and slag is determined by this slag determining means. If it is determined that the torch rotation start command is issued, the slag avoidance command means for stopping the wire feeding and the output of the welding power source, and the torch rotation start command when the slag determination means detects the slag and the torch rotation start command is issued. To the department
An arc generation retry device for an automatic welding device, which is provided with a slag avoidance control means for instructing to rotate the torch and for instructing to start arc generation if there is an input of a signal notifying that the torch has rotated. ..