JP2002361414A - Method for completing consumable two-electrode arc welding, method for controlling completion of welding, and welding robot - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a method for completing arc welding in which two wires are fed in one torch for welding, in consumable electrode arc welding. SOLUTION: In the method for completing consumable two-electrode arc welding in which two wires are fed in one torch for welding, the feeding and energizing of a succeeding wire 4 are stopped at a welding completion position P2; while the welding torch is moved by a first crater fill distance D1 at a speed slower than the regular welding speed in the direction reversed from the welding direction, the first crater fill is performed by a preceding wire 3; and then, with the movement of the welding torch stopped, a second crater fill is performed by the preceding wire 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved method for terminating arc welding in which two consumable electrodes (hereinafter referred to as wires) are fed and welded within one torch in consumable electrode arc welding. .

[0002]

2. Description of the Related Art In the construction of various welded structures, work efficiency has been improved by performing thin plate high-speed welding or thick plate high-welding welding.
As shown in FIG. 1, a consumable electrode arc welding method of a two-electrode one-torch method in which two wires are fed from one torch is adopted. In the figure, power is supplied from a welding power source (not shown) between the preceding chip 1 and the following chip 2 and the work 8 to be welded, and the leading wire tip 3a fed from the preceding chip 1 and the following chip 2 respectively. And trailing wire tip 4
Arcs 5 and 6 are generated from a. The nozzle 10 surrounds the preceding chip 1 and the following chip 2 and supplies the shielding gas 11 to the inside of the nozzle 10.

In FIG. 2, the molten metal in a molten pool 7 formed by an arc 5 generated from a preceding wire 3 tends to flow backward due to surface tension. The molten metal whose force is about to flow backward is pushed back just below the arc 5 generated from the preceding wire 3 so that the amount of molten metal at each welding position is made uniform.

FIG. 3 is a view showing a general configuration of the above-described two-electrode one-torch welding robot. In the figure, a welding torch 14 having a leading tip 1 and a trailing tip 2 is attached to the tip of a manipulator 21, and a leading wire welding power supply device 23 for feeding the leading tip 1 and a trailing wire for feeding to the trailing tip 2. A welding power supply 24 supplies welding power between the preceding chip 1 and the following chip 2 and the workpiece 8, respectively. Advance wire feeder 25
And the following wire feeder 26 feeds the wires to the preceding chip 1 and the following chip 2 respectively. The robot control device 27 controls the manipulator 21, the power supply device 23 for preceding wire welding, and the power supply device 24 for following wire welding.
When the welding direction is changed, the leading and trailing lines are switched, so that the leading chip 1, the leading wire 3, the leading wire feeding device 25, the leading wire welding power supply device 23, the trailing chip 2, the trailing wire 4, and the trailing wire The description of each reference numeral of the row wire feeding device 26 and the following wire welding power supply device 24 is replaced with the preceding and following description.

[Prior art 1] Conventionally proposed 2
A method of terminating welding using a welding robot of the one-electrode torch type (hereinafter referred to as Conventional Technique 1) will be described with reference to FIGS. In order to simplify the description, the leading wire 3
And the case where the following wire 4 is fed. FIG. 4 is a view for explaining a method of terminating the consumable electrode arc welding of the two-electrode one-torch method of the prior art 1, and FIG. It is a figure explaining an end method.

FIG. 4A shows a state in which the consumable electrode arc welding of the two-electrode one-torch method is performed. In FIG.
0, the leading wire 3 and the trailing wire 4 protrude. Electric power is supplied to each of the gaps, and arcs 5 and 6 are generated from the leading wire tip 3a and the trailing wire tip 4a, respectively, to form a weld bead 9.

As shown in FIG. 4 (B), when the leading end 3a of the leading wire reaches the welding end position P2 which is the end of the welding bead formed by the leading wire 3, the robot controller shown in FIG. 27 determines that the leading wire tip 3a has reached the welding end position P2, and outputs a crater processing command signal to the leading wire welding power supply device 23 and the following wire welding power supply device 24.

Here, the crater process will be described. At the end of the weld bead, a so-called crater is formed in the molten pool immediately below the arc due to the arc force. Defects such as cracks and shrinkage holes are likely to occur in this crater. In order to prevent this, the operation of reducing or eliminating the crater is called crater processing. In general, a method of decreasing the welding current continuously or stepwise at the end of the welding bead or interrupting the welding current is used. In addition, the above-mentioned prior art 1
Is referred to as a second crater process in the present invention.

Thereafter, when the crater process is completed,
The robot control device 27 shown in FIG. 3 receives the welding end command signal from the preceding wire welding power supply device 23 and the following wire welding power supply device 24, and as shown in FIG.
End the welding.

FIG. 5 is a view showing the appearance of the end portion of a weld bead by the method of terminating the consumable electrode arc welding of the two-electrode one-torch method of the prior art 1. As shown in the figure, since both the leading wire 3 and the following wire 4 perform crater processing, two crater processing traces 15 and 16 are generated. Therefore, not only the appearance of the weld bead becomes poor, but also when the crater process is performed, a depression 15 is formed between the two crater process marks.
a occurs and the strength of the weld joint decreases. In addition, when performing high-speed welding, since the molten pool before the crater treatment is solidified without being subjected to the crater treatment and solidifies to form a molten pool mark 13, defects such as cracks and shrinkage holes are likely to occur.

[Prior Art 2] Japanese Patent Application Laid-Open No. 2001-113373 entitled "Control Method for Tandem Arc Welding" (hereinafter referred to as Prior Art 2) has been proposed to solve the above-mentioned problems. FIG. 6 is a diagram showing an apparatus for performing tandem arc welding according to Prior Art 2. In the figure, a power supply device 44 for leading wire welding and a power supply device 4 for following wire welding are provided between a leading tip 41 and a trailing tip 42 and the workpiece 2.
5 supply power respectively. Lead wire feeder 46
And the following wire feeder 47 supplies the leading wire 48 and the trailing wire 49 to the leading chip 41 and the trailing chip 42, respectively, to generate the arc 50 and the arc 51. The weld pool 52 is formed by the arc 50 and the arc 51, and a weld bead 53 is formed behind the weld pool 52. The welding control device 54 controls the operation of the welding robot 55 and the power supply device 44 for preceding wire welding and the power supply device 4 for following wire welding.
5 is performed.

FIG. 7 is a time chart for explaining a control method at the end of welding according to the prior art 2, wherein FIG. 7A shows the lapse of time t of the current flowing through the preceding wire, and FIG. FIG. 7C shows the elapsed time t of the moving speed of the preceding chip 41 and the succeeding chip 42, and FIG. 9D shows the elapsed time of the following wire energizing current. FIG. 7E shows the lapse of time t of the voltage applied to the succeeding wire.

At time t1 shown in FIG. 7, when the leading tip 41 reaches the welding end position P2, the current flowing through the leading wire 48 is reduced from I1 to I2, as shown in FIG. As shown in FIG.
The applied voltage of 8 is reduced from E1 to E2. Thereafter, after the elapse of the waiting time Td1, the arc of the leading wire 48 is stopped to reduce the size of the molten pool.

At time t2 in FIG.
Reaches the welding end position P2, the movement of the leading tip 41 and the trailing tip 42 is stopped, as shown in FIG. Then, as shown in FIG.
Is decreased from I3 to I4, and as shown in FIG.
From E4 to E4. Thereafter, the arc of the following wire 49 is stopped after the elapse of the waiting time Td2.

It is appropriate that the currents I2 and I4 reduced before the arc is stopped are about half of the normal welding currents I1 and I2, respectively. Further, the applied voltages E2 and E4 reduced before the arc is stopped may be set to values suitable for the reduced currents I2 and I4, respectively.

As described above, the current flowing through the leading wire 48 and the trailing wire 49 at the end of welding and the voltage to be applied are reduced, and the welding is stopped after the waiting time. In addition, it is disclosed that it is possible to obtain a good weld end portion having no welding defects such as irregularities, pits, and cracks, but has the following problems.

[0017]

In the above-mentioned prior art 2, as shown in FIG. 7, after the current and voltage applied to the leading wire 48 are reduced, welding is performed only by the trailing wire 49. . The welding speed at this time is a speed at which high-speed welding is performed, as shown in FIG. Accordingly, after the current and voltage applied to the leading wire 48 are reduced, the welding speed of the leading tip 41 and the trailing tip 42 is too fast to perform welding only by the arc of the trailing wire 49, so that the welding bead width is reduced. May decrease, insufficient penetration may occur, or humping beads may occur.
The weld bead near the welding end position cannot provide a uniform and beautiful appearance. In high-speed welding where the welding speed exceeds 2 [m / min], in order to obtain a uniform weld bead,
The ratio of the current flowing through the leading wire 48 to the current flowing through the following wire 49 is about 2: 1. Therefore, if the current supplied to the leading wire 48 is reduced and stopped while maintaining the speed of the high-speed welding, the ratio of the current supplied to the leading wire 48 and the following wire 49 is not an appropriate ratio, and high-speed welding is performed. In this case, the arc force of the following wire 49 becomes excessive, and this arc force blows off the molten pool, so that the weld bead becomes non-uniform and a welding defect occurs.

Further, in the prior art 2, for example, as shown in FIG. 8, the fillet welding of a bottom plate having a box-shaped workpiece 8 and a wall in front of the welding end position P2 in the welding direction is performed. In the case of performing, the leading tip 41 reaches the welding end position P2 and the leading tip 41 hits the wall, and the leading tip 41 and the trailing tip 42 cannot be moved in the welding direction. The method cannot be implemented. FIG. 8 is a diagram for explaining a case where the shape of the workpiece 8 is box-shaped and fillet welding of the bottom plate is performed. Therefore, the trailing tip 42 is at the welding end position P
2 cannot be reached, as shown in FIG.
Since the welding near the welding end position P2 is performed by only the leading wire 48, the welding bead 9a near the welding ending position P2 becomes thin or the welding bead 9 becomes uneven,
Weld defects occur. FIG. 9 is a diagram for explaining that the weld bead 9 at the welding end position P2 when performing the fillet welding of the bottom plate becomes non-uniform when the shape of the workpiece 8 is box-shaped according to the related art 2. .

[0019]

The invention described in claim 1 at the time of filing is the invention of the first embodiment shown in FIGS. 10 and 11, wherein two wires are fed within one torch. In the consumable two-electrode arc welding end method for welding, the welding end position P
In step 2, the feed and energization of the following wire 4 are stopped, and the leading wire 3 is moved to the first direction while moving the welding torch in the direction opposite to the welding direction at a speed lower than the normal welding speed by the first crater processing distance D1. This is a method of ending consumable two-electrode arc welding in which crater processing is performed, then movement of the welding torch is stopped, and the preceding wire 3 performs second crater processing.

The invention according to claim 2 at the time of filing is the consumable two-electrode arc welding in which the first crater processing distance D1 according to claim 1 at the time of filing is the "distance between the tip ends of the wires of the standard protrusion length" L2. This is the end method.

According to a third aspect of the present invention, there is provided a consumable two-electrode which calculates the first crater processing distance D1 from the first crater processing moving speed and the first crater processing moving time. This is a method for terminating arc welding.

The invention described in claim 4 at the time of filing is shown in FIG.
In the consumable two-electrode arc welding end method in which two wires are fed and welded in one torch according to the second embodiment shown in Fig. 1, when the leading tip 1 reaches the welding end position P2. While the feeding and energization of the following wire 4 are stopped, the first crater processing current value and the first crater processing current value are moved at the first crater processing speed lower than the normal welding speed while moving the welding torch in the direction opposite to the welding direction. The leading wire 3 performs the first crater treatment at the crater treatment voltage value, and then stops the welding torch when the leading wire 3 reaches the second crater treatment position P3, and the second crater treatment current value and the second crater treatment value According to the processing voltage value, the second crater processing is started and the measurement of the predetermined second crater processing time is started.
This is a consumable two-electrode arc welding termination method for terminating the crater process.

The invention described in claim 5 at the time of filing is an invention obtained by adding an anti-stick treatment and a welding release treatment to the invention described in claim 4 at the time of filing, and FIG. 13 and FIG. Is a consumable two-electrode arc welding end control method in which two wires are fed and welded within one torch, the leading tip 2 is located at a welding end position P.
"1st crater processing start position welding torch moving step" instructing the end of welding of the following wire 4 when the number reaches 2.
(Corresponding to step ST9) and a "first crater processing command step" (corresponding to step ST10) in which a command for performing the first crater processing at a first crater processing speed at which the preceding wire is lower than the normal welding speed is provided. And the subsequent wire 4 performs an anti-stick process and a welding release process, and after the anti-stick process and the welding release process,
When it is determined that there is no welding, the following wire welding ending process is completed (corresponding to step ST11), and when the preceding tip 1 reaches the welding ending position P2, the preceding wire welding ending process step is completed. While moving the welding torch in the direction opposite to the welding direction until the wire 3 reaches the second crater processing position P3, the leading wire 3 issues a command to perform the first crater processing at the first crater processing speed while the “first crater processing speed” is given.
Crater processing command step "(corresponding to step ST12) and" first crater processing step "for outputting a predetermined first crater processing current value and first crater processing voltage value when the first crater processing is commanded ( Step S
T12), when the welding torch moves in the direction opposite to the welding direction and reaches the second crater processing position P3, the welding torch is stopped and the preceding wire performs the second crater processing. (The step of starting the second crater process) (corresponding to step ST13)
When the crater processing is instructed, the second crater processing current value and the second crater processing voltage value are output, the measurement of the predetermined second crater processing time is started, and the measurement of the second crater processing time is completed. “Second crater processing step” (step ST1)
4), when the measurement of the second crater processing time expires, the anti-stick processing and the welding release processing of the preceding wire 3 are performed, and after the anti-stick processing and the welding releasing processing are completed, there is no welding of the preceding wire 3. When it is determined that
This is a consumable two-electrode arc welding end control method including a "preceding wire welding end processing step" (corresponding to step ST15) for completing the preceding wire welding end processing.

The invention according to claim 6 at the time of filing is the same as that of the second embodiment shown in FIGS. 13 and 15 (excluding the work program file output circuit 29 and the electrode parameters 31 in FIG. 15) and FIG. (Except for processing step ST11 and preceding wire welding end processing step ST15), a welding end control method embodying the invention of claim 5 at the time of filing, wherein two wires within one torch are connected. In the consumable two-electrode arc welding end control method of feeding and welding, when the leading tip 1 reaches the welding end position P2, the welding torch moving path calculation circuit 32 sends the following wire welding end processing command signal S10. It outputs to the row wire welding condition output circuit 36 and outputs the first crater processing command signal S11 to the preceding wire welding condition output circuit 35, and the speed is lower than the normal welding speed. The first crater processing speed is output to the servo control circuit 33, and the servo control circuit 33 moves the welding torch in a direction opposite to the welding direction (“first crater processing command signal output step”) (step ST10); The first crater processing command signal S is output to the output circuit 35.
When “11” is input, the preceding wire welding condition output circuit 35 outputs the first crater processing current value and the first crater processing voltage value to the power supply device for preceding wire welding “first crater processing step” (step ST12), the welding torch moves in the direction opposite to the welding direction, and the leading tip 1
Reaches the second crater processing position P3, the servo control circuit 33 stops the manipulator 21, and the welding torch moving path calculation circuit 32 sends the second crater processing command signal S13 to the preceding wire welding condition output circuit 35. The “second crater processing start step” to be output (step ST1
3), when the second crater processing command signal S13 is input to the preceding wire welding condition output circuit 35, the preceding wire welding condition output circuit 35 outputs the second crater processing current value and the second crater processing voltage value in advance. Power supply unit for wire welding 2
3 to start the measurement of a predetermined second crater processing time, and terminate the second crater processing when the measurement of the second crater processing time expires (“second crater processing step”) (step ST14). This is a consumable two-electrode arc welding end control method comprising:

The invention of claim 7 at the time of filing is an invention obtained by adding an anti-stick treatment and a welding release treatment to the invention of claim 6 at the time of filing, and is shown in FIGS. 13 and 15 (FIG. 15). 18 except for the work program file output circuit 29 and the electrode parameter 31) and the consumable two-electrode arc welding end control method for feeding and welding two wires in one torch. When the preceding tip 1 reaches the welding end position P2, the welding torch movement path calculation circuit 32 outputs the following wire welding end processing command signal S10 to the following wire welding condition output circuit 36, and performs the first crater processing. The command signal S11 is output to the preceding wire welding condition output circuit 35, the first crater processing speed lower than the normal welding speed is output to the servo control circuit 33, and the servo control is performed. The first crater processing command signal output step (step ST10) in which the road 33 moves the welding torch in the direction opposite to the welding direction, and the following wire from the welding torch movement path calculation circuit 32 to the following wire welding condition output circuit 36. When the welding end processing command signal S10 is input, the power supply unit for subsequent wire welding 24 performs anti-stick processing and welding release processing, and after the anti-stick processing and welding release processing is completed, the following wire welding condition output circuit 36.
Outputs a succeeding wire welding end processing completion signal S12 to the welding torch movement path calculation circuit 32 when it is determined that there is no welding of the succeeding wire 4 (step ST11). When the first crater processing command signal S11 is input to the preceding wire welding condition output circuit 35, the preceding wire welding condition output circuit 35
A “first crater processing step” (step ST12) in which the crater processing current value and the first crater processing voltage value are output to the power supply device for preceding wire welding 23; When 1 reaches the second crater processing position P3, the servo control circuit 33 stops the manipulator 21 and the welding torch moving path calculation circuit 32 outputs the second crater processing command signal S13 to the preceding wire welding condition output circuit 35. "Starting step for second crater processing" (step ST13) to be output to the second crater processing command signal S
13 is input, the preceding wire welding condition output circuit 35 outputs the second crater processing current value and the second crater processing voltage value to the preceding wire welding power supply device 23, and the predetermined second crater processing is performed. The measurement of time is started, and the second crater process is terminated when the measurement of the second crater process time has expired (step ST14).
When the measurement of the crater processing time has expired, the power supply device for preceding wire welding 23 performs an anti-stick process and a welding release process on the preceding wire, and the preceding wire welding condition output circuit 35 determines that the preceding wire 3 is not welded. The consumable two-electrode arc welding end control method includes a "preceding wire welding end processing step" (step ST15) for outputting a preceding wire welding end processing completion signal S14 to the welding torch movement path calculation circuit 32.

The invention according to claim 8 at the time of filing is the same as the invention according to claim 6 at the time of filing, except that “a preceding wire and a following wire welding start completion signal output step” ST8 shown in FIG.
13 and 15 and FIG. 17 and FIG. 18 of the second embodiment (excluding the subsequent wire welding end processing step ST11 and the preceding wire welding end processing step ST15). A control method,
In the consumable two-electrode arc welding end control method in which two wires are fed and welded in one torch, the standard protruding length L1 of the leading wire 3 or the trailing wire 4 and the leading wire 3 and "Electrode parameter setting step" for setting an electrode parameter including "the distance between the wire tips of the standard protruding length" L2 of the succeeding wire 4
(Step ST1), a “work program file setting step” for setting predetermined welding start parameters and welding end parameters in the work program file output circuit 29 in each welding section of the workpiece 8 (step ST2); The welding robot system is started, and the electrode parameters set in the electrode parameter output circuit 31 and the normal welding speed at a predetermined welding start position in each welding section of the work 8 set in the work program file output circuit 29 are determined. The welding current value and the welding voltage value of the preceding wire 3 and the first crater processing current value are output to the welding torch movement path calculation circuit 32 at a predetermined welding start position of each welding section of the workpiece 8 at each welding section. And the first crater processing voltage value, the second crater processing current value, and the second
Crater processing voltage value and preceding wire welding condition output circuit 3
5 and outputs a welding current value and a welding voltage value of the following wire 4 at a predetermined welding start position in each welding section of the workpiece 8 to be welded in the following wire welding condition output circuit 3.
"Input step of electrode parameter and crater processing work program file" output to step 6 (step ST3)
After the preceding wire welding start command signal S1 is inputted to the preceding wire welding condition output circuit 35 and the succeeding wire welding start command signal S2 is inputted to the following wire welding condition output circuit 36, the welding torch moving path calculating circuit 32, a first crater processing speed lower than a normal welding speed, which is a moving speed of the welding torch during the first crater processing period, from the work program file output circuit 29, and a second operation in which the welding torch moves in a direction opposite to the welding direction. The first crater processing distance D1 and the second crater processing time are input, and the welding end position P
Manipulator 21 for moving welding torch to 2
"Step of calculating welding end position welding torch movement path" (step ST7) for calculating each joint angle of the above, and when the leading tip 1 reaches the welding end position P2, the welding torch movement path calculation circuit 32 outputs the following wire. The welding end processing command signal S10 is output to the succeeding wire welding condition output circuit 36, the first crater processing command signal S11 is output to the preceding wire welding condition output circuit 35, and the welding torch movement path calculation circuit 32
Outputs the first crater processing speed to the servo control circuit 33, and the servo control circuit 33 moves the welding torch in a direction opposite to the welding direction, a "first crater processing command signal output step" (step ST10); When the first crater processing command signal S11 is input to the welding condition output circuit 35, the preceding wire welding condition output circuit 35 outputs the first crater processing current value and the first crater processing voltage value to the preceding wire welding power supply device 23. When the welding torch moves in the direction opposite to the welding direction and the preceding tip 1 reaches the second crater processing position P3, the servo control circuit 33 The manipulator 21 is stopped, and the welding torch movement path calculation circuit 32 outputs the second crater processing command signal S13 as a preceding wire welding condition output. And outputs it to the road 35 "second crater processing start step" (step ST13), the prior wire welding condition output circuit 35 to the second crater treatment command signal S1
3 is input, the leading wire welding condition output circuit 3
5 outputs the second crater processing current value and the second crater processing voltage value to the power supply device for preceding wire welding 23, starts measurement of a predetermined second crater processing time, and measures the second crater processing time. "Second crater processing step" (Step S)
T14).

As shown in FIG. 15 of the second embodiment (except for the work program file output circuit 29 and the electrode parameters 31 in FIG. 15),
In a welding robot that feeds and welds two wires in a torch, each joint angle of the manipulator 21 for moving the welding torch from a welding start position to a welding end position is calculated (a servo control circuit 33 described later). 2) Output the calculated values of the joint angles, and when the welding torch reaches the welding start position, output the preceding wire welding start command signal S1 (to the preceding wire welding condition output circuit 35 described later) and output the following wire. The welding start command signal S2 is output (to a later-described wire welding condition output circuit 36 described later), the normal welding speed is output (to a servo control circuit 33 described later), and the preceding tip 1 reaches the welding end position P2. At this time, the following wire welding end processing command signal S10 is output (to the following wire welding condition output circuit 36 described later), and the first crater processing command signal S11 is generated (the preceding crater processing command signal described later). Hate welding conditions output circuit 35
), And outputs a first crater processing speed lower than the normal welding speed (to a servo control circuit 33 described later). When the preceding chip 1 reaches the second crater processing position P3, the second crater processing speed is output. A welding torch movement path calculation circuit 32 that outputs a crater processing command signal S13 (to a preceding wire welding condition output circuit 36 described later), and each joint angle of the manipulator 21 for moving the welding torch from the welding torch movement path calculation circuit 32 Is input to control the manipulator 21, and when the first crater processing speed is input, the welding torch is moved in the direction opposite to the welding direction,
Servo control circuit 33 for stopping manipulator 21 when preceding chip 1 reaches second crater processing position P3
When the preceding wire welding start command signal S1 is input, a signal for instructing the leading wire 3 to supply a welding current is output (to the later described leading wire welding power supply device 23),
When the arc 5 is generated at the leading end 3a of the leading wire, a leading wire welding start completion signal S3 is output to the welding torch moving path calculation circuit 32, and the first crater processing command signal S1 is output.
When 1 is input, the first crater processing current value and the first crater processing voltage value are output (to the power supply device for preceding wire welding 23 described later), and the second crater processing command signal S is output.
When 13 is input, the second crater processing current value and the second crater processing voltage value are output (to the power supply device for preceding wire welding 23 described later), and measurement of a predetermined second crater processing time is started. When the measurement of the second crater processing time has expired, a command signal for stopping the supply and energization of the leading wire 3 is issued (the leading wire welding power supply device 23 described later).
A) a preceding wire welding condition output circuit 35 to be output, and a preceding wire for supplying a welding current to the preceding wire 3 when a signal for instructing to supply a welding current to the preceding wire is input from the preceding wire welding condition output circuit 35. Power supply unit 23 for welding
When the following wire welding start command signal S2 is inputted, a signal for instructing the energization of the welding current of the following wire is output (to the later described wire welding power supply 24 described later),
When the arc 6 is generated at the trailing wire tip 4a, the trailing wire welding start completion signal S4 is output to the welding torch movement path calculation circuit 32, and when the trailing wire welding end processing command signal S10 is input, A succeeding wire welding condition output circuit 36 that outputs a command signal for stopping the feeding and energization of the following wire 4 (to a later-described wire welding power supply 24 described later), The welding robot includes a trailing wire welding power supply device 24 that supplies a welding current to the trailing wire 4 when a signal for commanding the welding current to flow through the row wire is input.

The invention described in claim 10 at the time of filing is an invention obtained by adding an anti-stick treatment and a welding release treatment to the invention described in claim 9 at the time of filing.
As shown in FIG. 15 (excluding the work program file output circuit 29 and the electrode parameters 31), in a welding robot that feeds and welds two wires in one torch, welding is performed from a welding start position to a welding end position. Each joint angle of the manipulator 21 for moving the torch is calculated (to a servo control circuit 33 described later), and the calculated value of each joint angle is output. When the welding torch reaches the welding start position, the preceding wire welding is performed. A start command signal S1 is output (to a later-described preceding wire welding condition output circuit 35), a subsequent wire welding start command signal S2 is output (to a later-described later wire welding condition output circuit 36), and the normal welding speed is set. (To the servo control circuit 33 to be described later), and when the preceding tip 1 reaches the welding end position P2, the following wire welding end processing command signal S10 (to be described later). To the following wire welding condition output circuit 36, and to output the first crater processing command signal S11 (to the preceding wire welding condition output circuit 35, which will be described later). (To the servo control circuit 33 to be described later), and when the preceding chip 1 reaches the second crater processing position P3, the second crater processing command signal S13 is output to the preceding wire welding condition output circuit 36 to be described later. The calculated value of each joint angle of the manipulator 21 for moving the welding torch from the welding torch moving path calculating circuit 32 and the welding torch moving path calculating circuit 32 is input to control the manipulator 21 so that the first crater processing speed is reduced. When input, the welding torch is moved in the direction opposite to the welding direction, and when the leading tip 1 reaches the second crater processing position P3, the A servo control circuit 33 to stop the Regulator 21,
When the preceding wire welding start command signal S1 is input,
A signal for instructing the leading wire 3 to supply a welding current is output (to the leading wire welding power supply device 23 described later), and when the arc 5 is generated at the leading wire tip 3a, the leading wire welding start completion signal S3 is welded. The first crater processing current value and the first crater processing voltage value are output to the torch movement path calculation circuit 32 and when the first crater processing command signal S11 is input (to the power supply device for preceding wire welding 23 described later). When the second crater processing command signal S13 is input, the second crater processing current value and the second crater processing voltage value are output (to the power supply device for preceding wire welding 23 described later), and the predetermined When the measurement of the second crater processing time is started and the measurement of the second crater processing time is completed, a command signal for performing the anti-stick processing and the welding release processing of the preceding wire 3 is issued. Later preceding wire welding power supply 23) outputs, when it is determined that the welding without prior wire 3, the prior wire welding end processing completion signal S14
Is output to the welding torch movement path calculation circuit 32, and when a signal for commanding the application of the welding current of the preceding wire from the preceding wire welding condition output circuit 35 is input to the preceding wire 3, A power supply device 23 for preceding wire welding, which supplies a welding current and performs an antistick process and a welding release process on the leading wire 3 when a command signal for performing an antistick process and a welding release process on the preceding wire is input; Wire welding start command signal S2
Is input, a signal for instructing the energization of the welding current of the following wire (the power supply device 24 for the following wire welding described later).
When the arc 6 is generated at the leading wire end 4a, the trailing wire welding start completion signal S4 is outputted to the welding torch movement path calculating circuit 32, and the trailing wire welding end processing command signal S10 is inputted. When it is determined that the following wire 4 is not welded, a command signal for performing the anti-stick process and the welding release process of the following wire 4 is output (to the later-described wire welding power supply 24 described later). A subsequent wire welding condition output circuit 3 that outputs a subsequent wire welding end processing completion signal S12 to the welding torch movement path calculation circuit 32
6 and when a signal instructing the energization of the welding current of the following wire from the following wire welding condition output circuit 36 is input,
When a welding current is applied to the following wire 4 and a command signal for performing the anti-stick process and the welding release process of the following wire 4 is input, the following wire performs the anti-stick process and the welding release process of the following wire 4. This is a welding robot including a welding power supply device 24.

The invention of claim 11 at the time of filing is an invention in which a work program file output circuit 29 and an electrode parameter output circuit 31 shown in FIG. 15 are added to the invention of claim 9 at the time of filing. As shown in FIG. 15 of the second embodiment, in a welding robot that feeds and welds two wires within one torch, predetermined welding start parameters and welding end parameters in each welding section of the work 8 to be welded. And an electrode parameter comprising a predetermined "standard protrusion length of the leading wire 3 or the following wire 4" L1 and a "distance between the wire tips of the standard protrusion length" L2. Is output from the electrode parameter output circuit 31 and the work program file output circuit 29 which store the It calculates each joint angle of the manipulator 21 for moving the contact torch (to the servo control circuit 33 to be described later) and outputs the calculated values of each joint angle,
When the welding torch reaches the welding start position, the preceding wire welding start command signal S1 is output (to the later-described preceding wire welding condition output circuit 35), and the succeeding wire welding start command signal S2 is output to the later-described later wire welding condition. Welding condition output circuit 36
), And outputs the normal welding speed (to a servo control circuit 33 to be described later).
, The following wire welding end processing command signal S1
0 (to a later-described wire welding condition output circuit 36 to be described later), and outputs a first crater processing command signal S11 (to a preceding wire welding condition output circuit 35 to be described later). The first crater processing speed is output (to a servo control circuit 33 to be described later), and when the preceding chip 1 reaches the second crater processing position P3, the second crater processing command signal S13 is output (to output a preceding wire welding condition to be described later). Welding torch movement path calculation circuit 3 to be output to circuit 36)
2 and the calculated values of the joint angles of the manipulator 21 for moving the welding torch from the welding torch movement path calculation circuit 32 are input to control the manipulator 21;
When the first crater processing speed is input, the welding torch is moved in a direction opposite to the welding direction, and when the leading tip 1 reaches the second crater processing position P3, the manipulator 21 is moved.
When the preceding wire welding start command signal S1 is input, a signal for commanding the supply of the welding current to the preceding wire 3 is output (to the later described preceding wire welding power supply device 23). When the arc 5 is generated at the leading end 3a of the leading wire, the leading wire welding start completion signal S3 is output to the welding torch moving path calculating circuit 32,
When the first crater processing command signal S11 is input,
A first crater processing current value and a first crater processing voltage value are output (to a power supply device 23 for preceding wire welding described later),
When the second crater processing command signal S13 is input, the second crater processing current value and the second crater processing voltage value are output (to a later-described power supply device 23 for preceding wire welding),
The measurement of the predetermined second crater processing time is started, and when the measurement of the second crater processing time has expired, a command signal for stopping the supply and energization of the leading wire 3 is issued (a power supply device for leading wire welding described later). 23) a preceding wire welding condition output circuit 35 and a preceding wire welding condition output circuit 3
5, when a signal for commanding the supply of the welding current to the preceding wire 3 is input, a power supply device 23 for preceding wire welding for supplying a welding current to the preceding wire 3 and a subsequent wire welding start command signal S2 are input. When the arc 6 is generated at the trailing wire tip 4a, a signal for instructing the following wire 4 to supply a welding current to the trailing wire 4 is output. A wire welding start completion signal S4 is output to the welding torch movement path calculation circuit 32,
When the succeeding wire welding end processing command signal S10 is input, a succeeding wire welding that outputs a command signal to stop feeding and energization of the following wire 4 (to a later-described later wire welding power supply unit 24 described later). When the condition output circuit 36 and a signal for commanding the energization of the welding current of the following wire 4 from the following wire welding condition output circuit 36 are input, the following wire welding for applying the welding current to the following wire 4 The welding robot includes the power supply device 24.

The invention described in claim 12 at the time of filing is an invention obtained by adding an anti-stick treatment and a welding release treatment to the invention described in claim 11 at the time of filing.
As shown in FIG. 5, in a welding robot that feeds and welds two wires in one torch, predetermined welding start parameters and welding end parameters in each welding section of the workpiece 8 are stored. An electrode storing the work program file output circuit 29 and electrode parameters including a predetermined "standard protrusion length of the leading wire 3 or the following wire 4" L1 and a "distance between the wire tips of the standard protrusion length" L2. An output signal of the parameter output circuit 31 and an output signal of the work program file output circuit 29 are input, and each joint angle of the manipulator 21 for moving the welding torch from the welding start position to the welding end position is calculated (servo control described later). The circuit 33 outputs the calculated value of each joint angle, and when the welding torch reaches the welding start position, a preceding wire welding start command is issued. No. S1 is output (to a later-described preceding wire welding condition output circuit 35), a succeeding wire welding start command signal S2 is output (to a later-described later wire welding condition output circuit 36), and a normal welding speed is output (described later). And when the preceding tip 1 reaches the welding end position P2, outputs a succeeding wire welding end processing command signal S10 (to a later-described subsequent wire welding condition output circuit 36). The first crater processing command signal S11 is output (to the preceding wire welding condition output circuit 35 described later), and the first crater processing speed lower than the normal welding speed is output (to the servo control circuit 33 described later). When the leading tip 1 reaches the second crater processing position P3, a welding torch movement that outputs a second crater processing command signal S13 (to a later-described preceding wire welding condition output circuit 36). When the calculated values of the respective joint angles of the manipulator 21 for moving the welding torch from the path calculation circuit 32 and the welding torch movement path calculation circuit 32 are input to control the manipulator 21, and the first crater processing speed is input. A servo control circuit 33 that moves the welding torch in the direction opposite to the welding direction and stops the manipulator 21 when the preceding tip 1 reaches the second crater processing position P3;
When the preceding wire welding start command signal S1 is input,
A signal for commanding the supply of the welding current to the leading wire 3 is output (to the leading wire welding power supply device 23 described later), and when the arc 5 is generated at the leading wire tip 3a, the leading wire welding start completion signal S3 is welded. The first crater processing current value and the first crater processing voltage value are output to the torch movement path calculation circuit 32 and when the first crater processing command signal S11 is input (to the power supply device for preceding wire welding 23 described later). When the second crater processing command signal S13 is input, the second crater processing current value and the second crater processing voltage value are output (to the power supply device 23 for preceding wire welding described later), The measurement of the crater processing time is started, and when the measurement of the second crater processing time has expired, a command signal for performing the anti-stick processing and the welding release processing of the preceding wire 3 is given as ( The output of the preceding wire welding power supply unit 23 described above, and when it is determined that there is no welding of the preceding wire 3, the preceding wire welding completion processing completion signal S14 is output to the welding torch movement path calculation circuit 32. When a signal for instructing the application of the welding current of the preceding wire 3 is input from the circuit 35 and the preceding wire welding condition output circuit 35, the welding current is supplied to the preceding wire 3 to perform anti-stick processing and welding of the preceding wire 3. When a command signal for performing the release processing is input, a power supply device 23 for preceding wire welding that performs antistick processing and welding release processing of the preceding wire 3 and a subsequent wire welding start command signal S
2 is input, a signal for instructing the energization of the welding current of the following wire 4 is output (to the later-described wire welding power supply device 24 described later), and the arc 6 is generated at the leading wire tip 4a. Then, the following wire welding start completion signal S4 is output to the welding torch movement path calculation circuit 32, and when the following wire welding end processing command signal S10 is inputted, the anti-stick processing and the welding release processing of the following wire 4 are performed. (To the later-described power supply 24 for wire welding described later)
A trailing wire welding condition output circuit 36 that outputs a trailing wire welding end processing completion signal S12 to the welding torch movement path calculating circuit 32 when it is determined that there is no welding of the trailing wire 4; When a signal instructing the energization of the welding current of the following wire 4 is input from the condition output circuit 36, the welding current is applied to the following wire 4 and
Power supply unit 24 for performing the anti-stick processing and the welding release processing of the following wire 4 when the command signal for performing the anti-stick processing and the welding release processing is input
And a welding robot comprising:

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram that best illustrates the features of the invention according to the present application. Since this is the same as FIG. 10 described later, the description will be given later with reference to FIG. An embodiment of the present invention is a welding robot according to claim 12 at the time of filing, wherein the welding robot feeds and welds two wires in one torch. A work program file output circuit 29 that stores a predetermined welding start parameter and a predetermined welding end parameter, and a predetermined “standard protrusion length of the leading wire 3 or the following wire 4” L1 and “standard protrusion length” Distance between wire tips "
The output signal of the electrode parameter output circuit 31 storing the electrode parameter consisting of L2 and the output signal of the work program file output circuit 29 are input to the manipulator 21 for moving the welding torch from the welding start position to the welding end position. The joint angle is calculated (to a servo control circuit 33 to be described later), and the calculated value of each joint angle is output. When the welding torch reaches the welding start position, the preceding wire welding start command signal S1 is output to the preceding wire (to be described later). To the welding condition output circuit 35, output the subsequent wire welding start command signal S2 (to the later described wire welding condition output circuit 36), and output the normal welding speed (servo control circuit 33 described later).
), When the preceding tip 1 reaches the welding end position P2, outputs a succeeding wire welding end processing command signal S10 (to a succeeding wire welding condition output circuit 36 described later) and outputs a first crater processing command. The signal S11 is output (to the later-described preceding wire welding condition output circuit 35), the first crater processing speed lower than the normal welding speed is output (to the later-described servo control circuit 33), and the preceding chip 1 2
When reaching the crater processing position P3, a welding torch movement path calculation circuit 32 that outputs a second crater processing command signal S13 (to a preceding wire welding condition output circuit 36 described later).
And the calculated values of the joint angles of the manipulator 21 for moving the welding torch from the welding torch moving path calculation circuit 32 are input to control the manipulator 21. When the first crater processing speed is input, the welding torch is activated. When the leading tip 1 moves in the direction opposite to the welding direction and the leading tip 1 reaches the second crater processing position P3, when the servo control circuit 33 for stopping the manipulator 21 and the leading wire welding start command signal S1 are input, A signal for commanding the supply of the welding current to the leading wire 3 is output (to the leading wire welding power supply device 23 described later), and when the arc 5 is generated at the leading wire tip 3a, the leading wire welding start completion signal S3 is welded. The first crater processing current value and the first crater processing current value are output to the torch movement path calculation circuit 32 and when the first crater processing command signal S11 is input. The regulator treatment voltage value (the preceding wire welding power supply 23 to be described later) and outputs,
When the second crater processing command signal S13 is input, the second crater processing current value and the second crater processing voltage value are output (to a later-described power supply device 23 for preceding wire welding),
The measurement of the predetermined second crater processing time is started, and when the measurement of the second crater processing time expires, a command signal for performing the anti-stick processing and the welding release processing of the preceding wire 3 is issued (for the preceding wire welding A preceding wire welding condition output circuit 35, which outputs a preceding wire welding end processing completion signal S14 to the welding torch movement path calculating circuit 32 when it is determined that the preceding wire 3 is not welded. When a signal for commanding the application of the welding current of the preceding wire 3 is input from the welding condition output circuit 35, a command signal for applying the welding current to the preceding wire 3 and performing anti-stick processing and welding release processing of the preceding wire 3 is performed. Wire welding power supply device 23 that performs anti-stick processing and welding release processing of preceding wire 3 when is input
When the following wire welding start command signal S2 is inputted, a signal for instructing the energization of the welding current of the following wire 4 is output (to the following wire welding power supply 24 described later),
When the arc 6 is generated at the trailing wire tip 4a, the trailing wire welding start completion signal S4 is output to the welding torch movement path calculation circuit 32, and when the trailing wire welding end processing command signal S10 is input, A command signal for performing the anti-stick processing and the welding release processing of the succeeding wire 4 is output (to the later-described power supply 24 for subsequent wire welding), and when it is determined that there is no welding of the succeeding wire 4, the welding torch moving path is determined. The succeeding wire welding end processing completion signal S12 is sent to the calculation circuit 32.
Is output from the following wire welding condition output circuit 36, and when a signal instructing the energization of the welding current of the following wire 4 is input from the following wire welding condition output circuit 36, the welding current is supplied to the following wire 4. A power supply unit 24 for welding the subsequent wire 4 to perform an anti-stick process and a welding release process on the following wire 4 when a command signal for performing an anti-stick process and a welding release process of the following wire 4 is inputted when a current is supplied; Is a welding robot.

[0032]

Embodiment 1 Hereinafter, a method for terminating welding will be described in Embodiment 1, and a robot controller 27 will be described in Embodiment 2.
Will be described below.

Embodiment 1 FIG. 10 is a view for explaining an embodiment of a consumable two-electrode arc welding termination method according to the present invention. FIG. 4A shows a state during the consumable electrode arc welding of the two-electrode one-torch method, and the same reference numerals are given to the same functions shown in FIG.

As shown in FIG. 10B, when the leading wire tip 3a reaches the welding end position P2, the robot controller 27 shown in FIG.
Has reached the welding end position P2, and outputs a welding end command signal to the succeeding wire welding power supply device 24,
The first crater processing command signal is output to the preceding wire welding power supply device 23. L2 shown in FIG. 10 (B) is a distance between the tip ends of the wires having the standard protruding length, and can be used as a later-described first wire crater processing distance D1 of a later-described wire. Thereafter, as shown in FIG. 3C, the leading wire 3 performs the first crater processing while the welding torch moves the first crater processing distance D1, for example, the distance L2 between the wire tips in the direction opposite to the welding direction. .

Here, the first crater process is a process of stopping the feeding and energizing of the succeeding wire 4 and energizing only the preceding wire 3 to move the welding torch in the direction opposite to the welding direction, and terminate the welding. Is to do. The welding current value, welding voltage value and welding speed during the first crater processing period can be set arbitrarily. Usually, the welding current value and welding voltage of welding (hereinafter, referred to as normal welding) until the welding torch reaches the welding end position. The value is lower than the welding speed.

FIG. 11 is a view for explaining a method of terminating the welding subsequent to FIG. 10 in the method of terminating the welding of the first embodiment. FIG.
FIGS. 11A to 11C subsequent to 0 (C) will be described. When the welding torch has moved the first crater processing distance D1, for example, the distance L2 between the wire tips in the direction opposite to the welding direction, the welding torch stops, and the robot control device 27 shown in FIG. A second crater processing command signal is output to the welding power source device 23, and FIG.
As shown in (A), the leading wire 3 performs a second crater process.

Here, the second crater process is to process the crater with the welding torch stopped after the preceding wire 3 has performed the first crater process. Can be set arbitrarily. This corresponds to the crater process described in the related art 1.

When the preceding wire 3 has completed the second crater process, the robot controller 27 shown in FIG.
However, a welding end command signal is output to the preceding wire welding power supply device 23, and the welding is ended as shown in FIG. 11 (B).

As described above, in the first embodiment, only the leading wire 3 performs the crater process described in the prior art 1 in the second crater process, and therefore, as shown in FIG. Only one occurs. Further, since the moving speed of the welding torch during the first crater process shown in FIG. 10 (C) is reduced from the speed of normal welding, the molten metal generated by the preceding wire 3 while moving the welding torch is arced. The molten metal is pushed in the moving direction of the torch by the force, and this molten metal can fill the recessed molten pool due to the arc force of the following wire 4, and the weld pool trace 13 shown in FIG. Is good in appearance.

Further, in the case where the shape of the workpiece 8 shown in FIG. 8 is box-shaped and the bottom plate having a wall on the front surface in the welding direction at the welding end position P2 is to be subjected to fillet welding, the leading wire 3 is not welded. After reaching the position P2, after the energization of the following wire 4 is stopped, the preceding wire 3 and the following wire 4 are moved in the direction opposite to the welding direction, and the preceding wire 3 performs the first crater process, and After the subsequent wire 4 has moved the first crater processing distance D1, the preceding wire 3 performs the second crater processing, so that the uniform welding bead 9 as shown in FIG.
Can be obtained. FIG. 12 is a diagram for explaining a case in which the shape of the workpiece 8 is box-shaped and fillet welding of the bottom plate is performed by the welding termination method of the first embodiment.

In the first embodiment, the first crater processing distance D1 is set to “the distance between the wire tips having the standard protrusion length” L
It can be 2. Also, the first crater processing distance D
1 can be calculated from the first crater processing moving speed and the first crater processing moving time. Further, the first crater processing distance D1 can be calculated as a percentage of the "distance between the wire tips of the standard protrusion length" L2.

[Explanation of FIG. 13] FIG. 13 shows welding from the welding start position P1 to the first crater processing start position and the second crater processing position when the leading wire 3 of the first embodiment of the present invention performs crater processing. It is a figure for explaining a moving distance of a torch. In the same figure, a distance from a “welding start position” P1 which is a starting end of a welding bead formed by the following wire 4 at the start of welding to a “welding end position” P2 which is a terminating end of the welding bead formed by the preceding wire 3. Is calculated as the total welding torch moving distance L3. Here, the “welding end position” and the “first crater processing start position” are the same position. Then, the welding torch is moved at a normal welding speed until the position of the following chip 2 reaches the welding end position P2 (first crater processing start position) from the welding start position P1 to the preceding chip 1. Then, the normal welding speed is maintained until the preceding tip 1 moves from the welding end position P2 (first crater processing start position) by the first crater processing distance D1 in the direction opposite to the welding direction to the second crater processing position P3. The welding torch is moved at the first crater processing speed that is slower than that.

As shown in FIG. 13, the welding termination method of the first embodiment is a welding termination method in which the feeding and energization of the following wire 4 are stopped and the preceding wire 3 performs the first and second crater processes. When the leading tip 1 reaches the welding end position P2, the feeding and energization of the trailing wire 4 are stopped, and the welding torch is moved in the opposite direction to the welding direction while moving the welding torch in a direction opposite to the normal welding speed. When the leading wire 3 performs the first crater processing at the first crater processing current value and the first crater processing voltage value at one crater processing speed, and then, when the preceding wire 3 reaches the second crater processing position P3, welding is performed. The torch is stopped, the second crater processing time is started, and the measurement of the second crater processing time is started based on the second crater processing current value and the second crater processing voltage value. A consumable second electrode arc welding termination method to end the second crater treatment when expired measurement.

[Second Embodiment] Next, a description will be given of a welding end control method and a welding robot according to a second embodiment of the present invention. [Explanation of FIG. 14] FIG. 14 is a diagram showing the leading tip 1 and the trailing tip with respect to the center axis of the nozzle 10 when the welding line WL used in the second embodiment is the X axis and the center axis of the nozzle 10 is the Y axis. FIG. 4 is a diagram showing a positional relationship between a leading wire tip 3a and a trailing wire tip 4a when the tip 2 is arranged at an angle. In FIG. 14 in which the leading chip 1 and the trailing chip 2 are arranged at an angle with respect to the Y axis of the center axis of the nozzle 10, the leading chip angle α is such that the center axis of the leading chip 1 advances to the center Y axis of the nozzle. The trailing tip angle β is an angle in which the center axis of the trailing tip 2 is inclined by the receding angle β to the center Y axis of the nozzle.
Or, the standard protrusion length of the succeeding wire 4 ”L1 (for example, 20
[mm]) is the tip position (tool center position) of the leading wire 3 or the trailing wire 4 when the leading wire 3 or the trailing wire 4 is projected from the tip of the leading tip 1 or the trailing wire 2 by a predetermined length. ), And the “distance between the wire tips of the standard protruding length” L2 is the length of the preceding wire and the following wire when the protruding length of the preceding wire 3 or the following wire 4 is the standard protruding length L1. , Which are predetermined set values.

[Description of FIG. 15] FIG. 15 is a block diagram of a robot control device 27 when the welding end method or the welding end control method of the present invention is applied to the welding robot shown in FIG. In FIG. 15, a work program file output circuit 29 stores predetermined welding start parameters and welding end parameters in each welding section of the workpiece 8. Here, the “welding start parameter” is a welding current value and a welding voltage value of the leading wire 3 and the following wire 4 at the welding start position of each welding section, and a normal welding speed. The “welding end parameter” is a condition of the first and second crater processes performed by the preceding wire 3, and includes a first crater process current value, a first crater process voltage value, and a first crater process period. The moving speed of the welding torch in the direction opposite to the welding direction, the moving distance of the welding torch (D1 shown in FIG. 13), the second crater processing current value, the second crater processing voltage value, and the second crater processing time are parameters. .

Further, the first crater processing distance D1 in the second embodiment may be set to, for example, "the distance between the wire tips of the standard protrusion length" L2. Alternatively, the moving time of the welding torch during the following wire and the first crater processing period may be set. In this case, (first crater processing distance) D1 = (movement speed of welding torch during first crater processing period) × (movement time of welding torch during first crater processing period). Alternatively, the distance may be specified as a percentage of “the distance between the wire ends of the standard protrusion length” L2 and set as (first crater processing distance) D1 / L2 [%].

According to the experiments by the inventors, when the molten pool is depressed to the extent that the molten pool mark 13 is formed as shown in FIG. In order to fill the pond, it is necessary to move the preceding tip 1 in a direction opposite to the welding direction more than the "standard distance between the tip ends of the wires of the protruding length" L2. Therefore, as shown in FIG. 13, the first crater processing distance D1 is set to be longer than the "distance between the wire tips having the standard protrusion length" L2.

The electrode parameter output circuit 31 shown in FIG.
In FIG. 14, the leading end position of the leading wire 3 or the trailing wire 4 when the leading wire 3 or the trailing wire 4 projects from the leading end of the leading tip 1 or the trailing tip 2 shown in FIG. "Standard protrusion length of leading wire 3 or trailing wire 4" which is the length up to (tool center position) L
1 (for example, 20 [mm]) and the distance between the leading ends of the leading wire 3 and the trailing wire 4 when the trailing length of the leading wire 3 or the trailing wire 4 is the standard trailing length L1. An electrode parameter consisting of "distance between wire tips" L2 is stored.

The welding torch moving path calculation circuit 32
Receives the output signal of the work program file output circuit 29, calculates the joint angles of the manipulator 21 for moving the welding torch from the welding start position to the welding end position, and sends the calculated angles to the servo control circuit 33 described later. The calculated value of the joint angle is output.

The servo control circuit 33 receives the calculated values of the joint angles of the manipulator 21 for moving the welding torch from the welding torch moving path calculation circuit 32 and controls the manipulator 21.

The preceding wire welding condition output circuit 35 outputs a preceding wire welding start command for instructing the leading torch 1 to reach a predetermined welding start position and supplying a welding current to the preceding wire 3 from the welding torch moving path calculating circuit 32. When the signal S1 is input, the work program file output circuit 2
9 outputs a signal instructing to supply a welding current of a welding current value of the preceding wire 3 output by the leading wire 3. The power supply device for leading wire welding 23 supplies a welding current to the leading wire 3 when a signal for instructing to supply a welding current to the leading wire is input from the leading wire welding condition output circuit 35.

The succeeding wire welding condition output circuit 36 instructs the succeeding tip 2 to reach a predetermined welding start position and instructs the following wire 4 to supply a welding current to the succeeding wire 4 from the welding torch movement path calculating circuit 32. When the wire welding start command signal S2 is input, the work program file output circuit 2
9 outputs a signal instructing the energization of the welding current of the welding current value of the succeeding wire 4 output by the wire 9. The power supply device 24 for following wire welding supplies a welding current to the following wire 4 when a signal instructing to supply a welding current to the following wire is input from the following wire welding condition output circuit 36.

[Embodiment 2] Embodiment 2 is described with reference to FIGS.
As shown in FIG. 7 and FIG. 18, the feeding and energization of the following wire 4 are stopped at the welding end position P2, and the leading wire 3 is moved to the first direction while moving the welding torch in the direction opposite to the welding direction.
A welding end control method and a welding robot for performing a crater process, subsequently substantially stopping a welding torch and performing a second crater process. FIG. 1 shows a welding end control method according to the second embodiment.
As shown in FIG. 3, when the leading tip 1 reaches the welding end position P2, the feed and energization of the trailing wire 4 are stopped, and the welding torch is moved in the opposite direction to the welding direction while the normal welding speed is reduced. The first wire 3 performs the first crater process at the first crater process current value and the subsequent wire first crater process voltage value at the slow first crater process speed, and then the preceding wire 3 moves to the second crater process position P3. When the welding torch is stopped, the second crater processing current is started by the second crater processing current value and the second crater processing voltage value, and the measurement of the second crater processing time is started,
This is a consumable two-electrode arc welding end control method for terminating the second crater processing when the measurement of a predetermined second crater processing time has expired.

Next, the operation of the robot controller 27 according to the second embodiment will be described with reference to the time charts of signals in FIG.
This will be described with reference to the flowchart shown in FIG. [Explanation of FIG. 16] FIG. 16 is a diagram showing signals output by the welding torch moving path calculation circuit 32 of the robot controller of the second embodiment and the moving speeds of the preceding chip 1 and the following chip 2. In the same figure, FIG. 7A shows the elapsed time t of the preceding wire welding start instruction signal S1, FIG. 8B shows the elapsed time t of the first crater processing instruction signal S11, and FIG. ) Shows the lapse of time t of the second crater processing command signal S13, and FIG.
FIG. 8E shows the elapsed time t of the following wire welding start command signal S2, and FIG. 7F shows the elapsed time t of the following wire welding end processing command signal S10. The lapse t is shown. Here, in order to simplify the explanation, it is assumed that the path between the welding start position and the welding end position in each welding section is taught by one straight line.

[Description of FIGS. 17 and 18] FIGS. 17 and 18 are flowcharts showing the operation of the robot control device 27 of the second embodiment. Step ST1 shown in FIG.
In the “electrode parameter setting step”, the standard protrusion length L1 of the leading wire 3 or the trailing wire 4 and the leading wire 3 and the trailing wire 4
The electrode parameters are set including the “distance between the wire tips of the standard protrusion length” L2.

In step ST2 "work program file setting step", predetermined welding start parameters and welding end parameters in each welding section of the workpiece 8 are set in the work program file output circuit 29.

At step ST3 "input step of electrode parameter and crater processing work program file" shown in FIG. 17 and at time t1 shown in FIG. 16, the welding robot system is started, and the electrode parameters set in the electrode parameter output circuit 31 and the work are performed. The normal welding speed at a predetermined welding start position in each welding section of the workpiece 8 set in the program file output circuit 29 is output to the welding torch movement path calculation circuit 32. Further, the welding current value and welding voltage value of the preceding wire 3 at the welding start position of each predetermined welding section in each welding section of the workpiece 8, the first crater processing current value, the first crater processing voltage value, and the second The second crater processing current value and the second crater processing voltage value are output to the preceding wire welding condition output circuit 35, and the succeeding wire 4 at a predetermined welding start position in each welding section of each welding section of the workpiece 8 is welded. Are output to the subsequent wire welding condition output circuit 36.

In step ST4 “calculation of welding start position welding torch moving path, output step” shown in FIG.
The welding torch movement path calculation circuit 32 calculates each joint angle of the manipulator 21 for moving the welding torch to the welding start position, and outputs the calculated value of each joint angle to the servo control circuit 33.

Step ST5 "leading wire and trailing wire welding start signal output step" shown in FIG. 17 and FIG.
When the welding torch moves to the welding start position at time t2 shown in FIG. 4 and reaches the calculated value of the joint angle at the welding start position described in step ST4, the welding torch movement path calculation circuit 32 starts the preceding wire welding. The command signal S1 is output to the preceding wire welding condition output circuit 35, and the following wire welding start command signal S2 is output to the following wire welding condition output circuit 36.

In step ST6 “starting the energization of the leading wire and the following wire” shown in FIG. 17, the preceding wire welding start command signal S1 is input to the preceding wire welding condition output circuit 35, and the following wire welding start command signal S2 is generated. When input to the succeeding wire welding condition output circuit 36, the preceding wire welding condition output circuit 35 and the following wire welding condition output circuit 36 are respectively applied to the preceding wire 3 and the following wire 4 at the welding start position. The supplied welding current value and welding voltage value are output to the leading wire welding power supply device 23 and the trailing wire welding power supply device 24 to energize the leading wire 3 and the trailing wire 4, respectively.

In step ST7 "step of calculating the welding end position welding torch moving path" shown in FIG. 17, the preceding wire welding start command signal S1 is input to the preceding wire welding condition output circuit 35, and the succeeding wire welding start command signal S2 is generated. After being input to the succeeding wire welding condition output circuit 36, the welding torch moving path calculating circuit 32 outputs the first crater processing speed and the welding speed, which are the moving speed of the welding torch during the first crater processing period, from the work program file output circuit 29. The first crater processing distance (D1 shown in FIG. 13) in which the welding torch moves in the direction opposite to the direction and the second crater processing time are input, and each joint of the manipulator 21 for moving the welding torch to the welding end position. Calculate the angle.

In the step ST8 "outputting the preceding wire and subsequent wire welding start completion signal" step, when the arc 5 and the arc 6 are generated at the leading wire tip 3a and the trailing wire tip 4a, respectively, the preceding wire welding condition output circuit. 35 and the following wire welding condition output circuit 36 output the preceding wire welding start completion signal S3 and the following wire welding start completion signal S4 to the welding torch movement path calculation circuit 32, respectively.

In step ST9 “first crater processing start position welding torch moving step” shown in FIG. 18, the welding torch moving path calculation circuit 32 receives the preceding wire welding start completion signal S3 and the following wire welding start completion signal S4. Then, the welding torch moving path calculation circuit 32 calculates the joint angles of the manipulator 21 for moving the preceding tip 4 to the welding end position P2 (first crater processing start position) calculated in step ST7 shown in FIG. Output to the servo control circuit 33. As a result, the manipulator 21 starts a linear operation at a preset normal welding speed and performs normal welding.

At a step ST10 “first crater processing command signal output step” shown in FIG. 18 and at a time t3 shown in FIG. 16, the preceding chip 1 moves to the welding end position P2 (first
(The crater processing start position) and reaches the calculated joint angle at the welding end position P2 (the first crater processing start position) described in step ST7 shown in FIG. The succeeding wire welding end processing command signal S10 is output by the following wire welding condition output circuit 36.
And outputs the first crater processing command signal S11 to the preceding wire welding condition output circuit 35. Further, the welding torch movement path calculation circuit 32 outputs the first crater processing speed to the servo control circuit 33, and the servo control circuit 33 moves the welding torch in a direction opposite to the welding direction.

At step ST11 "step of finishing the subsequent wire welding" shown in FIG. 18 and at time t3 shown in FIG. 16, the following wire welding condition output circuit 36 outputs the following processing from the welding torch moving path calculation circuit 32 to the following wire welding end processing. When the command signal S10 is input, the power supply device 24 for subsequent wire welding performs anti-stick processing and welding release processing. Then, after the end of the anti-stick processing and the welding release processing, when the succeeding wire welding condition output circuit 36 determines that there is no welding, the following wire welding end processing completion signal S12 is output to the welding torch moving path calculation circuit 32. . Here, the anti-stick processing means that the motor feeds the wire by the inertial force even after the stop signal is input to the wire feeding device. Therefore, when the wire plunges into the molten pool and the molten pool cools, the tip of the wire adheres (sticks) to the deposited metal. In order to prevent this stick, after a stop signal is input to the wire feeder, a current smaller than the welding current value is applied to continue the melting of the wire and prevent the wire from plunging into the molten pool. It is. In the welding release process, after the current supply to the wire is terminated, it is detected whether or not the tip of the wire is welded to the workpiece by, for example, a short-circuit detection circuit or a welding current relay. Then, when welding is detected, a no-load voltage is applied between the tip of the wire and the work to be energized, and the wire is burned up to release the welding.

In step ST12 “first crater processing step” shown in FIG. 18, when the preceding wire welding condition output circuit 35 receives the first crater processing command signal S11, the preceding wire welding condition output circuit 35 The first crater processing current value and the first crater processing voltage value are output to the preceding wire welding power supply device 23.

At step ST13 “second crater processing start step” shown in FIG. 18 and at time t4 shown in FIG. 16, the welding torch moves in the direction opposite to the welding direction.
When the calculated value of the joint angle at the second crater processing position P3 shown in FIG. 13 calculated in step ST7 shown in FIG. 7 is reached, the servo control circuit 33 stops the manipulator,
The welding torch moving path calculation circuit 32 outputs the second crater processing command signal S13 to the preceding wire welding condition output circuit 35.

In step ST14 "second crater processing step" shown in FIG. 18, when the preceding wire welding condition output circuit 35 receives the second crater processing command signal S13, the preceding wire welding condition output circuit 35 The second crater processing current value and the second crater processing voltage value are output to the preceding wire welding power supply device 23, and the measurement of the second crater processing time is started.

In step ST15 “preceding wire welding end processing step” shown in FIG. 18, when the preceding wire welding condition output circuit 35 completes the measurement of the second crater processing time, the preceding wire welding power supply device 23 The anti-stick process and the welding release process are performed. When the preceding wire welding condition output circuit 35 determines that there is no welding of the preceding wire 3 after the end of the anti-stick process and the welding release process, the preceding wire welding completion process completion signal S14 is output to the welding torch moving path calculation circuit 32. I do.

In step ST16 “next welding section welding step” shown in FIG. 18, when the welding torch moving path calculation circuit 32 receives the preceding wire welding end processing completion signal S14 and the following wire welding end processing completion signal S12, The steps ST4 shown in FIG. 17 to step ST15 shown in FIG. 18 are repeated to perform welding for the next welding section.
When the welding of all the welding sections set in the work program file output circuit 29 is completed, the activation of the welding robot is stopped.

The welding end control method according to the second embodiment described above is summarized as follows. In the welding end control method according to the second embodiment, the electrode parameter output circuit 31 outputs the standard protruding length L1 of the leading wire 3 or the following wire 4 and the “distance between the wire ends of the standard protruding length of the preceding wire 3 and the following wire 4”. "Electrode parameter setting step" (step ST1) for setting the electrode parameters including "L2", and the work program file output circuit 29 stores predetermined welding start parameters and welding end parameters in each welding section of the work 8 to be welded. "Step for setting work program file" (step ST2) to be set, the welding robot system is started, the electrode parameters set in the electrode parameter output circuit 31, and the welding of the workpiece 8 set in the work program file output circuit 29 The normal welding speed at the predetermined welding start position in the section The welding current value and the welding voltage value, the first crater processing current value, and the first crater of the preceding wire 3 at the welding start position of each predetermined welding section of each welding section of the workpiece 8 are output to the output circuit 32. The processing voltage value, the second crater processing current value, and the second crater processing voltage value are output to the preceding wire welding condition output circuit 35, and at a predetermined welding start position of each welding section in each welding section of the workpiece 8 to be welded. The "electrode parameter and crater processing work program file input step" (step ST3) for outputting the welding current value and the welding voltage value of the following wire 4 to the following wire welding condition output circuit 36; Calculates the joint angles of the manipulator 21 for moving the welding torch to the welding start position, and calculates the calculated value of each joint angle in the servo control circuit 33. When the welding torch reaches the welding start position, the welding torch movement path calculation circuit 32 outputs the preceding wire welding start command signal S1. Lead wire welding condition output circuit 3
5 to output the following wire welding start command signal S2 to the following wire welding condition output circuit 36 (step ST5) and a preceding wire welding start command. When the signal S1 is input to the preceding wire welding condition output circuit 35 and the following wire welding start command signal S2 is input to the following wire welding condition output circuit 36, the preceding wire welding condition output circuit 35 and the following wire welding are output. The condition output circuit 36 compares the welding current value and the welding voltage value supplied to the leading wire 3 and the following wire 4 at the welding start position with the leading wire welding power supply 2.
3 and the following wire welding power supply 24 to energize the preceding wire 3 and the following wire 4, respectively, and the welding torch movement path calculation circuit 32 outputs the normal welding speed to the servo control circuit 33. The wire and subsequent wire energization start step ”(step ST6), the preceding wire welding start command signal S1 is input to the preceding wire welding condition output circuit 35, and the following wire welding start command signal S2 is output to the following wire welding condition output circuit. After being input to the welding torch 36, the welding torch moving path calculating circuit 32 outputs the first crater processing speed and the welding direction which are lower than the normal welding speed at the moving speed of the welding torch during the first crater processing period from the work program file output circuit 29. The first crater processing distance D1 in which the welding torch moves in the opposite direction and the second crater processing time are input, and the Calculating each joint angle of the manipulator 21 for moving the contact torch "welding end position welding torch movement route calculation step" (step ST
7) and when the arc 5 and the arc 6 are generated at the leading wire tip 3a and the trailing wire tip 4a, respectively, the leading wire welding condition output circuit 35 and the trailing wire welding condition output circuit 36 output the preceding wire welding start completion signal. "Preceding wire and following wire welding start completion signal output step" for outputting S3 and succeeding wire welding start completion signal S4 to welding torch movement path calculation circuit 32, respectively (step ST8).
The welding torch moving path calculation circuit 32 outputs the preceding wire welding start completion signal S3 and the following wire welding start completion signal S3.
4 is input, the welding torch moving path calculation circuit 3
2 is the welding end position P2 calculated in step ST7
Manipulator 21 for moving preceding chip 4 to
The first torch moving position welding torch moving step (step ST9) for outputting each joint angle to the servo control circuit 33, and the welding torch moving path calculating circuit when the preceding tip 1 reaches the welding end position P2. 32 outputs the following wire welding end processing command signal S10 to the following wire welding condition output circuit 36, and outputs the first crater processing command signal S1.
1 to the preceding wire welding condition output circuit 35, the welding torch moving path calculation circuit 32 outputs the first crater processing speed to the servo control circuit 33, and the servo control circuit 33 sets the welding torch in the direction opposite to the welding direction. "First crater processing command signal output step" to be moved (step ST10)
When the following wire welding condition output circuit 36 receives the following wire welding end processing command signal S10 from the welding torch movement path calculation circuit 32, the following wire welding power supply device 24 performs anti-stick processing and welding release. When the following wire welding condition output circuit 36 determines that there is no welding of the following wire 4 after the completion of the anti-stick process and the welding release process, the following wire welding is terminated by the welding torch moving path calculation circuit 32. A "subsequent wire welding end processing step" for outputting a processing completion signal S12 (step ST11);
When the preceding wire welding condition output circuit 35 receives the first crater processing command signal S11, the preceding wire welding condition output circuit 35 outputs the first crater processing current value and the first crater processing voltage value to the power supply for the preceding wire welding. “First crater processing step” output to the device 23 (step ST1
2) and when the welding torch moves in the direction opposite to the welding direction and reaches the second crater processing position P3, the servo control circuit 33 stops the manipulator, and the welding torch moving path calculation circuit 32 The “second crater processing start step” (step ST13) in which the second crater processing command signal S13 is output to the preceding wire welding condition output circuit 36, and the second crater processing command signal S13 is input to the preceding wire welding condition output circuit 35. At this time, the preceding wire welding condition output circuit 35 outputs the second crater processing current value and the second crater processing voltage value to the preceding wire welding power supply device 23,
The “second crater processing step” (step ST14) for starting the measurement of the second crater processing time, and the power supply device for the preceding wire welding when the preceding wire welding condition output circuit 35 completes the measurement of the second crater processing time. 23 performs anti-stick processing and welding release processing of the preceding wire, and when the preceding wire welding condition output circuit 35 determines that there is no welding of the preceding wire 3, the welding torch movement path calculating circuit 32
To output a preceding wire welding end processing completion signal S14 to the "preceding wire welding end processing step" (step ST1).
5) A consumable two-electrode arc welding end control method comprising:

Embodiment 2 to which the above-mentioned welding end control method is applied
The following summarizes the welding robot. The welding robot according to the second embodiment includes a work program file output circuit 29 that stores a predetermined welding start parameter and a predetermined welding end parameter in each welding section of the workpiece 8, a predetermined preceding wire 3 or a predetermined following wire. Wire 4
An electrode parameter output circuit 31 storing the electrode parameters including the standard protrusion length L1 and the distance L2 between the wire tips of the standard protrusion length, and an output signal of the work program file output circuit 29 are input to the welding start position. To calculate the joint angles of the manipulator 21 for moving the welding torch to the welding end position (to a servo control circuit 33 described later) and output the calculated value of each joint angle,
When the welding torch reaches the welding start position, the preceding wire welding start command signal S1 is output to the (preceding wire welding condition output circuit 35 to be described later), and the following wire welding start command signal S2 is outputted to the following wire (to be described later). The normal welding speed is output to the welding condition output circuit 36 (servo control circuit 3 described later).
3), and when the preceding tip 1 reaches the welding end position P2, outputs the succeeding wire welding end processing command signal S10 (to the succeeding wire welding condition output circuit 36 described later) to perform the first crater processing. A command signal S11 is output (to a later-described preceding wire welding condition output circuit 35), a first crater processing speed lower than a normal welding speed is output to a (shorter control circuit 33 described later), and the preceding tip 1 When reaching the crater processing position P3, a welding torch movement path calculation circuit 32 that outputs a second crater processing current value and a second crater processing voltage value (to a preceding wire welding condition output circuit 36 described later), and a welding torch movement The calculated values of the joint angles of the manipulator 21 for moving the welding torch from the path calculation circuit 32 are input, the manipulator 21 is controlled, and the first crater process is performed. When it is, enter the degrees,
When the welding torch is moved in the direction opposite to the welding direction and the leading tip 1 reaches the second crater processing position P3, the servo control circuit 33 for stopping the manipulator and the leading wire welding start command signal S1 are input. Then, a signal for commanding the application of the welding current to the preceding wire 3 is output (to the later-described preceding wire welding power supply device 23), and when the arc 5 is generated at the leading wire tip 3a, the preceding wire welding start completion signal S3 Is output to the welding torch movement path calculating circuit 32, and when the first crater processing command signal S11 is input, the first crater processing current value and the first crater processing voltage value (the power supply device 23 for the preceding wire welding described later) To)
When the second crater processing command signal S13 is input, the second crater processing current value and the second crater processing voltage value are set (the power supply device 23 for the preceding wire welding described later).
) And start measuring the second crater processing time,
When the measurement of the second crater processing time has expired, a command signal for performing anti-stick processing and welding release processing of the preceding wire is output (to the power supply device 23 for preceding wire welding described later) to determine that there is no welding of the preceding wire 3. When the determination is made, the leading wire welding condition output circuit 35 that outputs the leading wire welding end processing completion signal S14 to the welding torch movement path calculation circuit 32, and the supply of the welding current of the leading wire 3 from the leading wire welding condition output circuit 35. When a command signal is input, a welding current is supplied to the preceding wire 3, and when a command signal for performing the anti-stick process and the welding release process is input to the preceding wire 3, the preceding wire 3 is subjected to the anti-stick process and Power supply unit for preceding wire welding 23 that performs welding release processing
When the following wire welding start command signal S2 is inputted, a signal for instructing the energization of the welding current of the following wire 4 is output (to the following wire welding power supply 24 described later),
When the arc 6 is generated at the trailing wire tip 4a, the trailing wire welding start completion signal S4 is output to the welding torch movement path calculation circuit 32, and when the trailing wire welding end processing command signal S10 is input, When the succeeding wire 4 outputs a command signal for performing the anti-stick process and the welding release process (to the later-described wire welding power supply 24 described later), and when it is determined that there is no welding of the succeeding wire 4, the welding torch moving path The succeeding wire welding end processing completion signal S12 is sent to the calculation circuit 32.
The welding current is supplied to the succeeding wire 4 when a signal for commanding the energization of the welding current of the following wire 4 is input from the succeeding wire welding condition output circuit 36 that outputs A power supply unit 24 for welding the subsequent wire 4 to perform an anti-stick process and a welding release process when a command signal for performing an anti-stick process and a welding release process is input to the following wire 4 when the current is supplied. Is a welding robot.

[0073]

The consumable two-electrode arc welding end method, the welding end control method and the welding robot of the present invention are the consumable electrode arc welding end method of the two-electrode one-torch method. The feeding and energization are stopped, and the welding torch is moved in a direction opposite to the welding direction at a welding speed slower than that during normal welding, and the first torch is moved only by the leading wire 3.
The crater process is performed, and thereafter, the movement of the welding torch is substantially stopped, and the second crater process is performed. Therefore, only one crater trace remains. Joint strength can also be secured. In addition, when performing high-speed welding, crater processing can also be performed on the hollow molten pool before performing crater processing.Therefore, no weld pool marks are generated at the welding end position, and defects such as cracks, shrinkage holes, etc. Will not occur. Further, even when fillet welding of a bottom plate having a box shape and a wall in front of the welding end position P2 in the welding direction at the welding end position P2 is performed, a uniform weld bead 9 can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram that best represents the features of the invention according to the present application.

FIG. 2 is a view for explaining a method for ending a consumable electrode arc welding of a two-electrode one-torch method.

FIG. 3 is a diagram showing a general configuration of a two-electrode one-torch welding robot;

FIG. 4 is a diagram for explaining a method of terminating a consumable electrode arc welding of a two-electrode one-torch method according to Prior Art 1.

FIG. 5 is a diagram illustrating a method of ending the consumable electrode arc welding of the two-electrode, one-torch method according to the prior art 1 following FIG. 4;

FIG. 6 is a diagram showing an apparatus for performing tandem arc welding according to Prior Art 2.

FIG. 7 is a time chart illustrating a control method at the end of welding according to Prior Art 2.

FIG. 8 is a diagram for explaining a case in which the shape of a workpiece 8 is box-shaped and fillet welding of a bottom plate is performed.

FIG. 9 is a view for explaining that a weld bead 9 at a welding end position P2 when performing a fillet welding of a bottom plate becomes non-uniform in a case where a shape of an object to be welded 8 is box-shaped according to a conventional technique 2; .

FIG. 10 illustrates a case in which the leading wire 3 and the trailing wire 4 are fed and the leading wire 3 performs the first and second crater processes in the consumable two-electrode arc welding termination method according to the first embodiment of the present invention. FIG.

FIG. 11 is a view for explaining a welding termination method following FIG. 10 in the welding termination method of the first embodiment.

FIG. 12 is a diagram showing a work 8 to be welded by the method for terminating welding of the first embodiment.
FIG. 4 is a diagram for explaining a case where the shape of a box is box-shaped and fillet welding of a bottom plate is performed.

FIG. 13 is a diagram for explaining a moving distance of a welding torch from a welding start position P1 to a first crater processing start position and a second crater processing position when the leading wire 3 of the present invention performs crater processing.

FIG. 14 shows that the leading tip 1 and the trailing tip 2 are angled with respect to the center axis of the nozzle 10 when the welding line WL used in the second embodiment is the X axis and the center axis of the nozzle 10 is the Y axis. FIG. 6 is a diagram showing a positional relationship between a leading wire tip 3a and a trailing wire tip 4a when the wires are arranged in a horizontal position.

15 is a block diagram of a robot control device 27 when the welding end method or the welding end control method of the present invention is applied to the welding robot shown in FIG.

FIG. 16 is a diagram illustrating a signal output from a welding torch movement path calculation circuit 32 of the robot control device according to the second embodiment and movement speeds of a preceding chip 1 and a following chip 2;

FIG. 17 is a flowchart illustrating an operation of the robot control device 27 according to the second embodiment.

FIG. 18 is a robot controller 2 according to a second embodiment following FIG. 17;
7 is a flowchart showing the operation of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Leading tip 2 Trailing tip 3 Leading wire 3a Leading wire tip 4 Trailing wire 4a Trailing wire tip 5, 6 Arc 7 Molten pool 8 Workpiece 9 Weld bead 10 Nozzle 11 Shield gas 13 Molten pool trace 14 Welding torch 15 , 16 Crater processing mark 21 Manipulator 23 Lead wire welding power supply 24 Trailing wire welding power supply 25 Leading wire feeder 26 Trailing wire feeder 27 Robot controller 29 Work program file output circuit 31 Electrode parameter output circuit 32 Welding torch movement path calculation circuit 33 Servo control circuit 35 Leading wire welding condition output circuit 36 Trailing wire welding condition output circuit 41 Leading tip 42 Trailing tip 44 Leading wire welding power supply 45 Trailing wire welding power supply 46 Leading Wire feeder 47 Follower Ear feeding device 48 Leading wire 49 Trailing wire 50, 51 Arc 52 Weld pool 53 Welding bead 54 Welding controller 55 Welding robot D1 First crater processing distance L1 Standard protrusion length of leading wire 3 or trailing wire 4 L2 Standard Distance between the protruding wire tips L3 Total welding torch movement distance P1 Welding start position P2 Welding end position P3 Second crater processing position S1 Leading wire welding start command signal S2 Trailing wire welding start command signal S3 Leading wire welding start completion signal S4 Trailing wire welding start completion signal S5 Leading wire welding end processing command signal S10 Trailing wire welding end processing command signal S11 First crater processing command signal S12 Trailing wire welding end processing completion signal S13 Second crater processing command signal S14 Wire welding end processing completion signal α Line chip angle after angle β

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4E001 AA03 BB08 BB09 DB01 QA01 QA04

Claims (12)

[Claims] 1. A method for ending a consumable two-electrode arc welding in which two wires are fed and welded in one torch, the feeding and energization of a subsequent wire are stopped at a welding end position to weld the welding torch. The leading wire performs the first crater process while moving in the opposite direction to the first crater process distance at a speed lower than the normal welding speed, and then stops the movement of the welding torch and causes the preceding wire to perform the second crater process. Consumable two-electrode arc welding end method. 2. The method for ending consumable two-electrode arc welding according to claim 1, wherein the first crater processing distance is a distance between the wire tips having a standard protrusion length. 3. The consumable two-electrode arc welding end method according to claim 1, wherein the first crater processing distance is calculated from the first crater processing moving speed and the first crater processing moving time. 4. A consumable two-electrode arc welding termination method in which two wires are fed and welded in one torch, and when a leading tip reaches a welding end position, feeding and energization of a following wire are stopped. While moving the welding torch in a direction opposite to the welding direction, the leading wire is moved to the first crater processing current value and the first crater processing voltage value at the first crater processing speed lower than the normal welding speed. Next, when the preceding wire reaches the second crater processing position, the welding torch is stopped, and the second crater processing is started with the second crater processing current value and the second crater processing voltage value, and A consumable two-electrode arc welding termination method for starting measurement of a predetermined second crater processing time and terminating the second crater processing when the measurement of the second crater processing time has expired. 5. A consumable two-electrode arc welding end control method in which two wires are fed and welded in one torch, and when the leading tip reaches a welding end position, a command to end welding of a succeeding wire is issued. A first crater processing start position welding torch moving step, and a first crater processing command step for giving a command for performing a first crater processing at a first crater processing speed of a preceding wire at a speed lower than a normal welding speed;
When the succeeding wire performs anti-stick processing and welding release processing, and after the anti-stick processing and welding releasing processing is completed, when it is determined that there is no welding of the succeeding wire, the succeeding wire welding end processing is completed. Processing steps;
When the leading tip reaches the welding end position, the leading wire is moved at the first crater processing speed while moving the welding torch in the direction opposite to the welding direction until the leading wire reaches the second crater processing position. A first crater processing command step for giving a command for crater processing, and a first crater processing step for outputting a predetermined first crater processing current value and first crater processing voltage value when the first crater processing is commanded When the welding torch moves in the direction opposite to the welding direction and reaches the second crater processing position, the welding torch is stopped and the preceding wire issues a command for performing the second crater processing. A crater processing start step, and outputting a second crater processing current value and a second crater processing voltage value when the preceding wire is instructed to perform the second crater processing; A second crater processing step for starting measurement of a predetermined second crater processing time, and terminating the second crater processing when the measurement of the second crater processing time has expired; and measuring the second crater processing time. Upon expiration, the anti-stick process and the welding release process of the preceding wire are performed, and after the completion of the anti-stick process and the welding release process, when it is determined that the preceding wire is not welded, the preceding wire welding completion process is completed. A consumable two-electrode arc welding end control method including an end processing step. 6. A consumable two-electrode arc welding end control method for feeding and welding two wires in one torch, wherein when a preceding tip reaches a welding end position, a welding torch moving path calculating circuit includes: A succeeding wire welding end processing command signal is output to a succeeding wire welding condition output circuit, and a first crater processing command signal is output to a preceding wire welding condition output circuit. Outputting a speed to a servo control circuit, wherein the servo control circuit moves a welding torch in a direction opposite to a welding direction, a first crater processing command signal output step, and the preceding wire welding condition output circuit outputs the first crater processing command signal. Is input, the preceding wire welding condition output circuit outputs the first crater processing current value and the first crater processing voltage value to the power supply device for preceding wire welding. A first crater processing step,
When the welding torch moves in the direction opposite to the welding direction and the preceding tip reaches the second crater processing position, the servo control circuit stops the manipulator, and the welding torch movement path calculation circuit calculates the second crater movement path. A second crater processing start step of outputting a processing command signal to the preceding wire welding condition output circuit; and outputting the preceding wire welding condition output signal when the second crater processing command signal is input to the preceding wire welding condition output circuit. The circuit outputs the second crater processing current value and the second crater processing voltage value to the power supply device for preceding wire welding, starts measuring a predetermined second crater processing time, and measures the second crater processing time. And a second crater processing step of terminating the second crater processing when the expiration is completed. 7. A consumable two-electrode arc welding end control method for feeding and welding two wires in one torch, wherein when a preceding tip reaches a welding end position, a welding torch moving path calculating circuit includes: A succeeding wire welding end processing command signal is output to a succeeding wire welding condition output circuit, and a first crater processing command signal is output to a preceding wire welding condition output circuit, so that the first crater process at a speed lower than a normal welding speed is performed. Outputting a speed to a servo control circuit, the servo control circuit moving a welding torch in a direction opposite to a welding direction, a first crater processing command signal output step, and the following wire welding condition output circuit calculating the welding torch moving path. When the subsequent wire welding end processing command signal is input from the circuit, the power supply unit for subsequent wire welding performs anti-stick processing and welding release processing, After completion of the sticking process and the welding release process, when the following wire welding condition output circuit determines that there is no welding of the following wire, the following wire welding completion process completion signal is output to the welding torch movement path calculation circuit. The following wire welding end processing step, and when the first crater processing command signal is input to the preceding wire welding condition output circuit, the preceding wire welding condition output circuit
A first crater processing step of outputting the crater processing current value and the first crater processing voltage value to the power supply device for preceding wire welding; A second crater processing start step of, when the servo control circuit stops the manipulator, the welding torch moving path calculation circuit outputting a second crater processing command signal to the preceding wire welding condition output circuit, When the second crater processing command signal is input to the preceding wire welding condition output circuit, the preceding wire welding condition output circuit outputs a second crater processing current value and a second crater processing voltage value for the preceding wire welding. Output to the power supply device, start the measurement of the second predetermined crater processing time, and the measurement of the second crater processing time has expired The ends of the second crater treatment 2
A crater processing step; when the preceding wire welding condition output circuit has completed the measurement of the second crater processing time, the preceding wire welding power supply device performs an anti-stick process and a welding release process on the preceding wire, and When the wire welding condition output circuit determines that there is no welding of the preceding wire, a preceding wire welding termination processing step of outputting a preceding wire welding termination processing completion signal to the welding torch movement path calculation circuit is completed. Control method. 8. A consumable two-electrode arc welding end control method in which two wires are fed and welded in one torch, wherein a standard protruding length of a leading wire or a trailing wire and a leading wire and a trailing wire are supplied to an electrode parameter output circuit. An electrode parameter setting step for setting an electrode parameter including a standard wire length of the row wire and a distance between the wire tips; a work program file output circuit; predetermined welding start parameters for each welding section of the work to be welded; and welding end. A work program file setting step of setting parameters; activating the welding robot system; electrode parameters set in the electrode parameter output circuit; and predetermined values in each welding section of the workpiece set in the work program file output circuit. The welding torch movement path calculation circuit calculates the normal welding speed at the welding start position And the welding current value and welding voltage value of the preceding wire at the welding start position of each predetermined welding section in each welding section of the workpiece, the first crater processing current value, the first crater processing voltage value, and The second crater processing current value and the second crater processing voltage value are output to the preceding wire welding condition output circuit, and the welding current of the succeeding wire at a predetermined welding start position in each welding section of each welding section of the workpiece. Inputting an electrode parameter and a crater processing work program file for outputting a value and a welding voltage value to a subsequent wire welding condition output circuit, and inputting a preceding wire welding start command signal to the preceding wire welding condition output circuit, After the start command signal is input to the succeeding wire welding condition output circuit, the work program file is sent to the welding torch movement path calculation circuit. The from the force circuit normal slower than welding speed rate is the moving speed of the welding torch of the first crater treatment period 1
A crater processing speed and a first crater processing distance and a second crater processing time at which the welding torch moves in a direction opposite to the welding direction are input, and each joint angle of the manipulator for moving the welding torch to the welding end position is calculated. A welding end position welding torch movement path calculating step, and when the preceding tip reaches the welding end position, the welding torch movement path calculation circuit outputs a succeeding wire welding end processing command signal to the subsequent wire welding condition output. The first crater processing command signal is output to the preceding wire welding condition output circuit, the welding torch movement path calculation circuit outputs the first crater processing speed to the servo control circuit, and the servo control circuit outputs A first crater processing command signal output step for moving the welding torch in a direction opposite to the welding direction, and the preceding wire welding condition output circuit A first crater process for outputting a first crater process current value and a first crater process voltage value to a preceding wire welding power supply device when the first crater process command signal is input; Step, when the welding torch moves in the direction opposite to the welding direction and the preceding tip reaches the second crater processing position, the servo control circuit stops the manipulator, and the welding torch moving path calculation circuit A second crater processing start step of outputting a second crater processing command signal to the preceding wire welding condition output circuit; and a step of, when the second crater processing command signal is input to the preceding wire welding condition output circuit, The wire welding condition output circuit
The second crater processing current value and the second crater processing voltage value are output to the power supply device for preceding wire welding, and the second
A consumable two-electrode arc welding end control method, comprising: starting the measurement of the crater processing time; and terminating the second crater processing when the measurement of the second crater processing time has expired. 9. A welding robot for feeding and welding two wires in one torch, calculating each joint angle of a manipulator for moving a welding torch from a welding start position to a welding end position (described later). Output the calculated value of each joint angle to the servo control circuit, and when the welding torch reaches the welding start position, output the preceding wire welding start command signal (to the preceding wire welding condition output circuit described later),
Outputs the following wire welding start command signal (to the later described wire welding condition output circuit), outputs the normal welding speed (to the later described servo control circuit), and when the preceding tip reaches the welding end position. , Output a subsequent wire welding end processing command signal (to a subsequent wire welding condition output circuit described later),
The first crater processing command signal is output (to a later-described preceding wire welding condition output circuit), and the first crater processing speed lower than the normal welding speed is output (to a later-described servo control circuit). A welding torch moving path calculation circuit that outputs a second crater processing command signal (to a later-described preceding wire welding condition output circuit) when reaching the second crater processing position; and a welding torch from the welding torch moving path calculation circuit. The calculated value of each joint angle of the manipulator for moving is input to control the manipulator, and when the first crater processing speed is input, the welding torch is moved in a direction opposite to the welding direction, and the leading tip 1 is moved.
When the robot reaches the second crater processing position, a servo control circuit that stops the manipulator and a signal that instructs the preceding wire to supply a welding current to the preceding wire when the preceding wire welding start command signal is input ( When the arc is generated at the leading end of the leading wire, a leading wire welding start completion signal is outputted to the welding torch movement path calculating circuit, and the first crater processing command signal is output. When input, the first crater processing current value and the first crater processing voltage value are output (to a power supply device for preceding wire welding described later), and when the second crater processing command signal is input, the second crater processing command signal is output. The crater processing current value and the second crater processing voltage value are output (to a power supply device for preceding wire welding described later), and measurement of a predetermined second crater processing time is started. When the measurement of the second crater processing time has expired, a preceding wire welding condition output circuit that outputs a command signal (to a later-described preceding wire welding power supply device) to stop feeding and energizing the preceding wire; When a signal for commanding the application of the welding current of the preceding wire is input from the wire welding condition output circuit, a power supply device for preceding wire welding that supplies the welding current to the preceding wire,
When the following wire welding start command signal is input,
A signal for commanding the energization of the welding current of the following wire is output (to a power supply device for the following wire welding described later). Output to the torch movement path calculation circuit,
When the succeeding wire welding end processing command signal is input, a succeeding wire welding condition output for outputting a command signal for stopping supply and energization of the succeeding wire (to a later-described later wire welding power supply device). Circuit, when a signal instructing the energization of the welding current of the succeeding wire is input from the subsequent wire welding condition output circuit, a power supply device for a subsequent wire welding that energizes the welding current to the subsequent wire. Welding robot. 10. In a welding robot that feeds and welds two wires within one torch, each joint angle of a manipulator for moving a welding torch from a welding start position to a welding end position is calculated (described later). Output the calculated value of each joint angle to the servo control circuit, and when the welding torch reaches the welding start position, output the preceding wire welding start command signal (to the preceding wire welding condition output circuit described later),
Outputs the following wire welding start command signal (to the later described wire welding condition output circuit), outputs the normal welding speed (to the later described servo control circuit), and when the preceding tip reaches the welding end position. , Output a subsequent wire welding end processing command signal (to a subsequent wire welding condition output circuit described later),
The first crater processing command signal is output (to a later-described preceding wire welding condition output circuit), the first crater processing speed lower than the normal welding speed is output (to a later-described servo control circuit), and the leading chip 1 is output. A welding torch moving path calculation circuit that outputs a second crater processing command signal (to a later-described preceding wire welding condition output circuit) when the motor reaches the second crater processing position; and a welding torch based on the welding torch moving path calculation circuit. The calculated value of each joint angle of the manipulator for moving the manipulator is input to control the manipulator, and when the first crater processing speed is input, the welding torch is moved in a direction opposite to the welding direction, and the leading tip is A servo control circuit that stops the manipulator when the second crater processing position is reached; When the arc is generated at the leading end of the leading wire, a signal for instructing the leading wire to supply a welding current to the leading wire is output (to a leading wire welding power supply device described later). It outputs to the welding torch movement path calculation circuit, and when the first crater processing command signal is inputted, outputs the first crater processing current value and the first crater processing voltage value (to a power supply device for preceding wire welding described later). Then, when the second crater processing command signal is input, the second crater processing current value and the second crater processing voltage value are output (to a power supply device for preceding wire welding described later), and the second crater processing is performed. The measurement of the processing time is started, and when the measurement of the second crater processing time has expired, a command signal for performing the anti-stick processing and the welding release processing of the preceding wire is issued (to be described later). A preceding wire welding condition output circuit that outputs a preceding wire welding end processing completion signal to the welding torch moving path calculation circuit when the preceding wire is determined to be not welded. When a signal for commanding the application of the welding current of the preceding wire is input from the welding condition output circuit, a command signal for applying the welding current to the preceding wire and performing anti-stick processing and welding release processing of the preceding wire is input. When the preceding wire welding power supply device performs anti-stick processing and welding release processing of the preceding wire, and when the following wire welding start command signal is input, a signal for commanding the energization of the welding current of the following wire is provided. (To a power supply unit for subsequent wire welding described later), and when an arc is generated at the leading end of the subsequent wire, the following wire welding start completion signal is output to the melting unit. It outputs to the contact torch movement path calculation circuit, and when the following wire welding end processing command signal is inputted, a command signal for performing anti-stick processing and welding release processing of the following wire (for the following wire welding for later described). Output to the power supply device, and when it is determined that there is no welding of the succeeding wire, a succeeding wire welding condition output circuit that outputs a succeeding wire welding end processing completion signal to the welding torch moving path calculation circuit; When a signal for commanding the energization of the welding current of the following wire is input from the wire welding condition output circuit, a command signal for energizing the welding current to the following wire and performing anti-stick processing and welding release processing of the following wire. A welding robot comprising a power supply device for subsequent wire welding, which performs an anti-stick process and a welding release process on the following wire when is input. 11. A work program for storing a predetermined welding start parameter and a predetermined welding end parameter in each welding section of an object to be welded in a welding robot for feeding and welding two wires in one torch. A file output circuit, an electrode parameter output circuit storing an electrode parameter including a predetermined standard extension length of the leading wire or the following wire and a distance between the wire tips of the standard extension length, and the work program file output circuit Is output, the joint angle of the manipulator for moving the welding torch from the welding start position to the welding end position is calculated (to a servo control circuit described later), and the calculated value of each joint angle is output. When the welding torch reaches the welding start position, a preceding wire welding start command signal is output (the preceding wire welding condition output Road), output the following wire welding start command signal (to the following wire welding condition output circuit described later), output the normal welding speed (to the servo control circuit described later), and the preceding chip finishes welding. When it reaches the position, it outputs a succeeding wire welding end processing command signal (to a later-described wire welding condition output circuit described later) and outputs the first crater processing command signal (to a later-described preceding wire welding condition output circuit). And outputs a first crater processing speed lower than a normal welding speed (to a servo control circuit described later). When the preceding chip reaches the second crater processing position, a second crater processing command signal is output. A welding torch moving path calculation circuit for outputting (to a preceding wire welding condition output circuit to be described later), and each of the manipulators for moving the welding torch from the welding torch moving path calculating circuit. When the calculated value of the angle is input to control the manipulator, when the first crater processing speed is input, the welding torch is moved in the direction opposite to the welding direction, and when the preceding tip reaches the second crater processing position. A servo control circuit for stopping the manipulator, and a signal for instructing the supply of welding current to the preceding wire when the preceding wire welding start command signal is input (to a power supply device for preceding wire welding described later). When an arc is generated at the leading end of the preceding wire, a preceding wire welding start completion signal is output to the welding torch moving path calculation circuit, and when the first crater processing command signal is input, the first crater processing current is output. And outputs the first crater processing voltage value (to a power supply device for preceding wire welding described later) and outputs the second crater processing command signal when the second crater processing command signal is input. The crater processing current value and the second crater processing voltage value are output (to a power supply device for preceding wire welding described later), the measurement of the second predetermined crater processing time is started, and the measurement of the second crater processing time is completed. Then, a command signal for stopping the supply and energization of the leading wire is sent to the leading wire welding power supply device described later.
A preceding wire welding condition output circuit to be output, and a power supply device for preceding wire welding that supplies a welding current to the preceding wire when a signal for commanding the application of a welding current to the preceding wire is input from the preceding wire welding condition output circuit. When the following wire welding start command signal is input, a signal instructing the energization of the welding current of the following wire is output (to a power supply device for later wire welding described later), and When an arc is generated, a trailing wire welding start completion signal is output to the welding torch movement path calculating circuit, and when the trailing wire welding end processing command signal is input, feeding and energizing of the trailing wire are performed. A welding signal output circuit for outputting a command signal (to a later-described wire welding power supply device to be described later) for stopping the welding, and a welding current of the succeeding wire from the following wire welding condition output circuit. Welding robot signal to command electric is when inputted, and a line wire welding power supply after passing a welding current to the trailing wire. 12. A work program for storing a predetermined welding start parameter and a predetermined welding end parameter in each welding section of an object to be welded in a welding robot for feeding and welding two wires in one torch. A file output circuit, and an electrode parameter output circuit storing an electrode parameter comprising a predetermined standard extension length of the leading wire or the following wire and a distance between the wire tips of the standard extension length,
An output signal of the work program file output circuit is input, and each joint angle of a manipulator for moving a welding torch from a welding start position to a welding end position is calculated (to a servo control circuit described later). The calculated value is output, and when the welding torch reaches the welding start position, the preceding wire welding start command signal is output (to the preceding wire welding condition output circuit described later), and the succeeding wire welding start command signal is described (described later). Output to the succeeding wire welding condition output circuit) and normal welding speed (to the servo control circuit described later)
Output, and when the preceding tip reaches the welding end position,
A subsequent wire welding end processing command signal is output (to a later-described wire welding condition output circuit described later), and a first crater processing command signal is output (to a preceding wire welding condition output circuit described later). Also outputs a first crater processing speed (to a servo control circuit described later) at a lower speed, and when the preceding chip reaches the second crater processing position, outputs a second crater processing command signal (preceding wire welding condition output described later). A circuit for calculating a joint torch movement path to be output to the circuit and a calculation value of each joint angle of the manipulator for moving the welding torch from the circuit for calculating a first torch. When the processing speed is input, the welding torch is moved in a direction opposite to the welding direction, and when the preceding tip reaches the second crater processing position, When the servo control circuit for stopping the manipulator and the preceding wire welding start command signal are input, a signal for instructing the supply of welding current to the preceding wire is output (to a power supply device for preceding wire welding described later), When an arc is generated at the wire tip, a preceding wire welding start completion signal is output to the welding torch moving path calculation circuit, and when the first crater processing command signal is input, the first crater processing current value and the first crater processing current value are output. One crater processing voltage value is output (to a power supply device for preceding wire welding described later), and when the second crater processing command signal is input, the second crater processing current value and the second crater processing voltage value are described (described later). Output to the preceding wire welding power supply device) to start measurement of a predetermined second crater processing time, and when the measurement of the second crater processing time has expired. Prior wire command signal for anti-stick treatment and welding cancellation process (the preceding wire welding power supply to be described later) and outputs, when it is determined that the welding without prior wires,
A preceding wire welding condition output circuit that outputs a preceding wire welding end processing completion signal to the welding torch movement path calculation circuit, and when a signal for instructing the application of the welding current of the preceding wire from the preceding wire welding condition output circuit is input. A power supply device for a preceding wire welding, which supplies a welding current to the preceding wire and performs an anti-stick process and a welding release process of the preceding wire when a command signal for performing the anti-stick process and the welding release process of the preceding wire is input. When the following wire welding start command signal is input, a signal for instructing the energization of the welding current of the following wire is output (to a power supply device for later wire welding described later), and an arc is generated at the tip of the following wire. Is generated, a following wire welding start completion signal is output to the welding torch movement path calculation circuit, and the following wire welding end processing command signal S When 0 is input, a command signal for the anti-stick treatment and welding release processing of the trailing wire 4 (the row wire welding power supply after that will be described later)
A trailing wire welding condition output circuit that outputs a trailing wire welding end processing completion signal to the welding torch movement path calculation circuit when it is determined that there is no welding of the trailing wire. When a signal for commanding the energization of the welding current of the subsequent wire is input from the circuit, a command signal for energizing the welding current to the subsequent wire and performing anti-stick processing and welding release processing of the subsequent wire was input. A welding robot including a power supply device for subsequent wire welding that sometimes performs anti-stick processing and welding release processing of the subsequent wire.