JP2019155418A - Arc-welding control method - Google Patents

Abstract

To improve an appearance of a welded portion by stabilizing arc generation at the starting time thereof.SOLUTION: Arc welding is performed by setting the sum of a welding current ON period Ton and a welding current OFF period Toff as a welding period Tc. An arc welding control method comprises: a first short circuit step for shorting a welding wire 18 with a base material 17 just before completion of the welding-current ON period Ton; and a wire tip end position control step for changing the tip end shape of the welding wire 18 by supplying first electric current Ic1 to the welding wire 18 at a first time T1 after the first short circuit step, so as to adjust the distance between the tip end of the welding wire 18 and the base material 17 to be a first distance WD1. The welding current OFF period Toff is started after completion of the wire tip end position control step.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an arc welding control method for performing arc welding by generating an arc between a welding wire as a consumable electrode and a base material as a welding object.

  Non-consumable electrode type TIG welding is widely used to realize a beautiful wave-shaped weld bead (hereinafter referred to as a scale-shaped bead) in welding of a bicycle or a motorcycle. In recent years, from the viewpoint of improving productivity, there is a great demand for replacing non-consumable electrode type TIG welding with consumable electrode type MIG welding or MAG welding. In the non-consumable electrode type TIG welding, since the electrode does not melt, it is necessary to supply a filler material separately from the electrode in the welding of a strength part that needs to increase the surplus of the bead.

  On the other hand, in consumable electrode type MIG welding and MAG welding, current is passed through the welding wire, which is the electrode, and arc welding generated between the welding wire and the base metal is used for welding while melting the welding wire. Is high and the welding speed can be increased.

  As a welding method for forming a scaly bead by consumable electrode type MIG welding or MAG welding, in Patent Document 1, welding was performed while the torch was stopped during the arc ON period, and the torch was stopped during the subsequent arc OFF period. Later, a method is described in which a scaly bead is formed by intermittent welding that repeats a series of operations of moving the torch while the arc is OFF, moving to the next welding point, and solidifying the base material.

  In addition, in order to improve the appearance design of the scaly beads, it is necessary to control the amount of heat input to the base material. For this purpose, for example, Patent Document 2 proposes an arc welding method in which a short-circuit transition period and a pulse transition period are controlled to be alternately repeated.

Japanese Patent Application Laid-Open No. 06-055268 JP-A-62-279087

  However, in the welding method disclosed in Patent Document 1, the amount of heat input to the base material during the arc ON period is large, and the base material may be melted down. Further, in the welding method disclosed in Patent Document 2, it is difficult to cause problems such as burnout by alternately repeating short heat welding with low heat input and pulse welding with high heat input. If the distance from the base material is set to a predetermined value or more, the arc is not stable at the transition from the short-circuit transition period to the pulse transition period, and the appearance of the welded portion is deteriorated. In particular, there has been a problem that the appearance design properties of the scaly beads are lowered.

  This invention is made | formed in view of this point, The objective is to provide the arc-welding control method which makes the external appearance of a welding location favorable, when performing arc welding by changing heat input periodically.

  In order to achieve the above object, an arc welding control method according to the present invention is provided with a welding current ON period in which a predetermined welding current flows in a welding wire, and after the welding current ON period, and the welding current is supplied to the welding wire. An arc welding control method for performing arc welding using a sum of a welding current off period in which no welding current flows as a welding cycle, and a first short-circuiting step for short-circuiting the welding wire with a base material immediately before the end of the welding current on-period; Then, after the first short-circuiting step, by supplying a first current to the welding wire at a first time, the tip shape of the welding wire is changed, and the tip of the welding wire, the base material, A wire tip position control step that adjusts the distance to be the first distance, and the welding current off period is started after the end of the wire tip position control step. And butterflies.

  According to this method, at the time of transition from the welding current on period to the welding current off period, the distance between the tip of the welding wire and the base material is supplied to the welding wire at the first time. Can be easily adjusted to the predetermined first distance. Further, by adjusting the distance between the tip of the welding wire and the base material to the first distance, it is possible to stabilize the rising at the start of arc generation in the next welding cycle. Moreover, the heat input difference in a welding location can be enlarged and the external appearance of a welding location can be made favorable.

  As described above, according to the present invention, it is possible to stabilize the rising at the start of arc generation and to improve the appearance of the welded portion.

It is a figure which shows schematic structure of the arc welding apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the various output waveforms at the time of arc welding which concern on Embodiment 1 of this invention. It is a schematic diagram which shows the shape of a scaly bead. It is a figure which shows the various output waveforms between the welding current ON time in one welding period, and the welding current OFF time. It is a figure which shows the various output waveforms at the time of completion | finish of arc welding. It is a figure which shows the various output waveforms between the continuous welding periods based on Embodiment 1 of this invention. It is a figure which shows the various output waveforms between the continuous welding periods for the comparison. It is a figure which shows the various output waveforms at the time of the arc welding which concerns on Embodiment 2 of this invention.

  Hereinafter, the present embodiment will be described in detail with reference to the drawings. The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or its application.

(Embodiment 1)
[Configuration and basic operation of arc welding equipment]
FIG. 1 is a diagram showing a schematic configuration of an arc welding apparatus according to the present embodiment. The arc welding apparatus 16 performs welding by repeating an arc state and a short-circuit state between a welding wire 18 that is a consumable electrode and a base material 17 that is a welding object. The welding wire 18 fed to the base material 17 is held by a torch (not shown), and when the torch moves at a predetermined speed, the distal end of the welding wire 18 is also predetermined at the same speed. It moves along the welding section.

  The arc welding device 16 includes a main transformer 2, a primary side rectification unit 3, a switching unit 4, a DCL (reactor) 5, a secondary side rectification unit 6, a welding current detection unit 7, and a welding voltage detection unit. 8, a control switching unit 9, an output control unit 10, and a wire feed speed control unit 13. Moreover, the arc welding apparatus 16 has a robot controller (not shown) that controls the operation of a robot (not shown) that holds a torch (not shown).

  The output control unit 10 includes a short-circuit welding control unit 11 and a pulse welding control unit 12. The wire feed speed control unit 13 includes a wire feed speed detection unit 14 and a calculation unit 15. The primary side rectification unit 3 rectifies the input voltage input from the input power source (three-phase AC power source) 1 outside the arc welding device 16. The switching unit 4 controls the output of the primary side rectification unit 3 to an output suitable for welding. The main transformer 2 converts the output of the switching unit 4 into an output suitable for welding.

  The secondary side rectification unit 6 rectifies the output of the main transformer 2. A DCL (reactor) 5 smoothes the output of the secondary side rectification unit 6 to a current suitable for welding. The welding current detector 7 detects the welding current. The welding voltage detector 8 detects the welding voltage.

  The control switching unit 9 is a switching unit that outputs to the output control unit 10 timing to switch from short-circuit welding control to pulse welding control and pulse welding to cooling period. The control switching unit 9 has a timekeeping function, measures the predetermined time set by the welding condition setting unit 22, and outputs the timing for switching control to the output control unit 10 and the wire feed speed control unit 13. . The “cooling period” is a period during which the welding current I is set to 0, and during this period, the amount of heat input from the arc is 0 (see FIG. 2).

  The output control unit 10 outputs a control signal to the switching unit 4 to control the welding output. The short-circuit welding control unit 11 controls short-circuit welding when the control switching unit 9 commands short-circuit welding. The pulse welding control unit 12 controls pulse welding when the control switching unit 9 commands pulse welding.

  The wire feeding speed control unit 13 controls the wire feeding unit 21 to feed the base material 17. The feeding speed of the welding wire 18 is controlled. The wire feed speed detector 14 detects the wire feed speed. The calculation unit 15 calculates an integrated amount of the feed amount of the welding wire 18 based on a signal from the wire feed rate detection unit 14 and controls the wire feed rate. Specifically, the difference between the command value of the wire feed speed and the detected value is obtained, and feedback control is performed so that the actual wire feed speed matches the command value based on the integrated amount of the difference. .

  A wire feeding unit 21 and a welding condition setting unit 22 are connected to the arc welding device 16. The welding condition setting unit 22 is used for setting welding conditions in the arc welding apparatus 16. The welding condition setting unit 22 includes a short circuit welding setting unit 23, a pulse welding setting unit 24, and a cooling period setting unit 25. The wire feeding unit 21 controls the feeding of the welding wire 18 based on the signal from the wire feeding speed control unit 13.

  The welding output of the arc welding device 16 is supplied to the welding wire 18 via the welding tip 20 when a torch SW (switch) (not shown) is turned on. Then, welding is performed by generating an arc 19 between the welding wire 18 and the base material 17 which is a welding object, based on the welding output of the arc welding device 16.

  Next, operation | movement of the arc welding apparatus 16 comprised as mentioned above is demonstrated using FIG. In this embodiment, at the time of arc welding, the first short-circuit welding, the pulse welding, and the second short-circuit welding are performed in this order, and then the arc welding apparatus 16 is operated so as to provide a cooling period in which the welding current is zero. A torch (not shown) that holds the welding wire 18 is controlled so as to move at a constant speed in a predetermined section where welding is performed. In other words, welding is performed when the torch is stopped, and the torch is not moved to the next teaching point after the welding is stopped, as in general stitch welding. The torch moves continuously so that it is maintained. Note that the welding speed may not be constant over the entire welded portion of the base material 17. For example, the welding speed may be changed in a portion where the thickness of the base material 17 changes.

  FIG. 2 is a diagram showing various output waveforms during arc welding according to the present embodiment, in arc welding in which the first short-circuit welding period Tss, the pulse welding period Tp, the second short-circuit welding period Tse1, and the cooling period Tn are repeated. , The feed speed W, the welding voltage V, the welding current I, and the time change of the droplet transfer state D at the tip of the welding wire 18 are shown.

  First, the feeding of the welding wire 18 is started at the feeding speed W1 from the time point Wst when the start of welding is instructed. The conditions set by the short-circuit welding setting unit 23 from the time point Wst at which the start of welding is instructed or from the time point Ed at which the start of welding is instructed and the occurrence of a short circuit between the welding wire 18 and the base material 17 as the welding object is detected. Then, the welding output is controlled by the short-circuit welding control unit 11, and the first short-circuit welding is performed between the welding wire 18 and the base material 17 so as to alternately repeat the short-circuit state and the arc state.

  Next, when a predetermined time Tss preset by the short-circuit welding setting unit 23 has elapsed, the control switching unit 9 switches from the first short-circuit welding to pulse welding in which the peak current and the base current are alternately repeated. Thereafter, the welding output is controlled by the pulse welding control unit 12 under the conditions set by the pulse welding setting unit 24, and pulse welding is performed from the pulse welding start point Pst (Pst1, Pst2) while repeating the peak current and the base current.

  When a predetermined time Tp set in advance by the pulse welding setting unit 24 elapses, the control switching unit 9 alternately repeats the short-circuit state and the arc state between the welding wire 18 and the base material 17 from the pulse welding. Switch to second short circuit welding. The welding output is controlled by the short circuit welding control unit 11 under the conditions set by the short circuit welding setting unit 23, and the second short circuit welding is performed.

  And if predetermined time Tse1 preset by the short circuit welding setting part 23 passes, the control switching part 9 will switch from a 2nd short circuit welding to a cooling period. However, although not shown in FIG. 3, as will be described later, a period for controlling the tip position of the welding wire 18 is provided during the transition from the second short-circuit welding to the cooling period (see FIG. 4). During a predetermined time Tn set by the cooling period setting unit 25, the output from the output control unit 10 is cut off. Thereby, the heat input by the arc can be reduced to zero. The above-mentioned first short-circuit welding period Tss, pulse welding period Tp, second short-circuit welding period Tse1, a preparation period Ta to be described later, and a tip position control period Tb of the welding wire 18 a welding current through which the welding current I flows. The ON period Ton, the cooling period Tn as the welding current OFF period Toff in which no welding current flows through the welding wire 18, the sum of the welding current ON period Ton and the welding current OFF period Toff as one welding cycle Tc, and these are repeated in order. A scaly bead is formed.

At this time, as shown in FIG. 2, after the first short-circuit welding period Tss, a pulse welding period Tp having a high heat input is provided, and thereafter, the average feed speed is repeated while repeating the forward feed and the reverse feed of the welding wire 18. A second short-circuit welding period Tse1 is provided in which the arc state and the short-circuit state are alternately performed while decreasing the average value of the welding current I and the welding voltage V. After that, a cooling period Tn in which the heat input is 0 is provided. That is, the welding cycle Tc of arc welding is expressed by the following formula (1).
Tc = Tss + Tp + Tse1 + Ta + Tb + Tn (1)

Further, the welding current ON period Ton and the welding current OFF period Toff are expressed by the following equations (2) and (3), respectively.
Ton = Tss + Tp + Tse1 + Ta + Tb (2)
Toff = Tn (3)

  By doing in this way, the cooling effect in a welding location can be improved, the difference in heat input can be maximized, and a scale-like bead with a clear wave shape can be realized. In the cooling period Tn, when the output of the welding current I and the welding voltage V is set to 0, the amount of heat input can be set to 0 and the cooling performance is the best. If only the welding current I is set to 0 and the welding voltage V is kept applied, the state in which the no-load voltage V1 is generated can be maintained, and the next arc start can be performed smoothly.

  The period from the pulse welding start time point Pst1 of the pulse welding period Tp to the pulse welding start time point Pst2 of the pulse welding period Tp of the next cycle is defined as the period Pc of the pulse welding period. The wave has a rough shape, and the shorter the wave, the denser the wave. In addition, the time length of this period Pc corresponds with the time length of the above-mentioned welding period Tc. Further, as will be described later, periods Ta and Tb in which a current flows through the welding wire 18 are provided immediately before the end of the welding current ON period Ton.

  Further, short-circuit welding has a shorter arc length than pulse welding, can shorten the distance WD1 (first distance WD1) from the tip of the welding wire 18 to the base material 17 at the end of welding, and the cooling period Tn. Can be reduced. Therefore, by reducing the time from the feeding start time Wst of the welding wire 18 to the current detection time Ed, it is possible to reduce the variation in the cooling period Tn, and to make the period Pc of the pulse welding period constant and uniform scaly beads. Can be formed. If the second short-circuit welding period Tse1 is too large, the amount of heat input at the welded portion increases, and the waviness of the scaly beads is not clear.

  In addition, if a molten pool is not formed immediately below the arc when the arc is generated in the pulse welding period Tp, the droplets of the welding wire 18 are blown off and spatter is generated when the peak current Ip is output. Therefore, the first short-circuit welding period Tss is provided before the pulse welding period Tp. As a result, when the pulse welding period Tp is switched, a molten ground is formed immediately below the arc, and generation of spatter due to the pulse current can be suppressed.

  At the time of arc start in the first short-circuit welding period Tss, as shown in FIG. 2, a no-load voltage V1 higher than the welding voltage during the pulse welding period Tp is output, and the welding wire 18 is moved at a constant feed speed W1. It is fed until it is short-circuited with the base material 17 and current is detected. The welding current I1 after the current detection is larger than the welding current when the short circuit is opened in the main welding. The welding current I1 is output for a predetermined period. During this period, the welding wire 18 is fed back with a predetermined amplitude. After the short circuit is opened, the welding wire 18 is fed while repeating normal feeding and reverse feeding with a predetermined amplitude and frequency. Although FIG. 2 shows a case where the feeding waveform is a sine wave, any feeding waveform such as a trapezoidal wave (not shown) may be used as long as it is a periodic waveform. Further, the frequency (period) may be constant or may vary. Further, when feeding is performed at a constant feeding speed that does not have a predetermined amplitude and frequency, management is easy, but sputtering due to electromagnetic pinch force is likely to occur when the short circuit is opened. Therefore, the sputter | spatter generation | occurrence | production at the time of the short circuit open | release in the 1st short circuit welding period Tss can be suppressed by mechanically forward-feeding and reverse-feeding the welding wire 18 with a predetermined amplitude and frequency.

  The droplet transfer state D at this time is shown at the bottom of FIG. The state (a) shows a droplet transfer state during the arc period of the short-circuit arc welding during the first short-circuit welding period Tss, and the welding wire 18 is fed forward while generating an arc. The state (b) shows the droplet transfer state during the short-circuit period of the short-circuit arc welding during the first short-circuit welding period Tss. After the droplet at the tip of the welding wire 18 is transferred to the base material 17, the wire is fed backward. , Mechanically urge to open the short circuit. Next, the feeding of the welding wire 18 in the pulse welding period Tp is performed at a constant feeding speed optimum for the welding current set by the pulse welding setting unit 24, and the state (c) is repeated while repeating the peak current and the base current. ), The droplet at the tip of the welding wire 18 is released. When the pulse welding period Tp ends, the feeding speed of the welding wire 18 is stopped as shown in the state (d), and the distance from the tip of the welding wire 18 to the base material 17 at this time is WD. Further, in the second short-circuit welding period Tse1, the above-described states (a) and (b) are repeated, and at the start of the cooling period Tn, from the tip of the welding wire 18 to the base material 17 as shown in the state (e). Is adjusted to be the first distance WD1. This will be described in detail later.

  After the cooling period Tn elapses, the next cycle is executed again, and as shown in the state (f), the welding wire 18 comes into contact with the base material 17 and the current is detected, and then the next first short-circuit welding period Tss is started again. . As described above, the arc maintained in the first and second short-circuit welding periods Tss, Tse1 and the pulse welding period Tp disappears in the cooling period Tn, and the arc is restarted when switching to the next first short-circuit welding period Tss. Since it is necessary to generate this, sputtering due to an electromagnetic pinch force is likely to occur when the short circuit is opened at the beginning of the arc start. However, in the present embodiment, during the first short-circuit welding period Tss, the welding wire 18 is mechanically forward-fed and reverse-fed, so that it is possible to suppress the occurrence of spatter during short-circuit opening at the initial stage of arc start. That is, the occurrence of spatter due to the electromagnetic pinch force can be reduced by feeding the welding wire 18 forward and backward in the first short-circuit welding period Tss and mechanically opening the short-circuit state.

  As shown in FIG. 2, the welding current I and the feed speed W in the first short-circuit welding period Tss are changed every moment. In particular, the average feeding speed of the feeding speed is gradually increased so as to approach the set feeding amount of the welding conditions in the pulse welding period Tp.

  The first and second short-circuit welding with a low heat input are performed by performing welding in a cycle in which the first short-circuit welding period Tss, the pulse welding period Tp, the second short-circuit welding period Tse1, and the cooling period Tn are sequentially repeated. By adjusting each of the heat input pulse welding and the cooling period in which the heat input is 0, the heat input to the base material 17 can be widely controlled, and the weld bead shape can be controlled more precisely. .

  FIG. 3 is a schematic diagram showing the shape of the scaly bead in the present embodiment. At the welding point shown in FIG. 3, after the arc welding described above is performed for one cycle or a plurality of cycles, the welding wire 18 and the torch are moved to the next welding point to perform the next arc welding. By repeating this sequentially along a predetermined trajectory, a plurality of scaly beads arranged continuously are formed. When the arc welding is finished up to the final point of the predetermined welding locus, the arc welding is finished as it is, or once the arc welding is finished and the welding wire 18 and the torch are moved to the starting point of another welding locus. Therefore, the welding wire 18 needs to be separated from the base material 17 by a predetermined distance WD2 so that the welding wire 18 can move at the end of arc welding. This will be described in detail later.

  In addition, during the first short-circuit welding period Tss, the welding wire 18 is fed with a predetermined amplitude and frequency, but is not limited thereto. As described above, the welding wire 18 may be fed at a constant feeding speed during the first short-circuit welding period Tss in order to facilitate management.

  Further, in the second short-circuit welding period Tse1, the average feeding speed of the welding wire 18 is gradually decreased with the inclination Ke. In the second short-circuit welding period Tse1, when the short-circuit and the arc generation are defined as one cycle, the average feeding of the welding wire 18 at an inclination Ke so that the second short-circuit welding period Tse1 is completed in the first to fifth cycles. Reduce speed. By doing so, the amount of heat input to the base material 17 can be gradually reduced. Note that the second short-circuit welding is performed with the average value of the wire feed speed being constant while the feed of the welding wire 18 is alternately repeated in the forward feed and the reverse feed, and the wire feed speed is set after the second short-circuit welding is completed. It may be attenuated.

  Further, during the pulse welding period Tp, the welding wire 18 is fed at a constant feeding speed, but is not limited thereto. During the pulse welding period Tp, the feeding speed of the welding wire 18 may be changed.

  Further, although the average feed speed Ws is increased to the constant feed speed during the pulse welding period Tp during the first short-circuit welding period Tss, the present invention is not limited to this. The average feed speed Ws at the end of the first short-circuit welding period Tss may be different from the constant feed speed during the pulse welding period Tp.

[Control of welding wire tip position]
FIG. 4 shows various output waveforms between the welding current on time and the welding current off time in one welding cycle according to the present embodiment. In addition, in FIG. 4, the time change waveform of the welding voltage V and the welding current I is shown similarly to FIG. In FIG. 4, the second short-circuit welding period Tse <b> 1, the preparation period Ta, and the tip position for feeding the welding wire that attenuate the average feeding speed while repeating the forward feeding and the reverse feeding of the welding wire 18 shown in FIG. For the control period Tb, the wire feed speed Wa is shown as an average speed for easy explanation. Further, during these periods, it is preferable to attenuate the average feed speed while repeating the forward feed and the reverse feed of the welding wire 18 and feed the welding wire. However, the feed speed of the welding wire 18 is increased during the forward feed. It may be lowered.

  As shown in FIG. 4, when the torch SW (switch) is turned off, in other words, when the low heat input transition signal is turned on (time point A), the transition starts from the pulse welding period Tp toward the cooling period Tn, The pulse welding period Tp is switched to the second short-circuit welding period Tse1, and the average feed speed Wa of the welding wire 18 decreases monotonously as described above.

  When the average feed speed Wa becomes equal to or less than a predetermined threshold (time point B), a preparation period Ta for controlling the tip position of the welding wire 18 is started. In the preparation period Ta, when the welding wire 18 is forwardly fed, the base material 17 and the welding wire 18 are short-circuited (first short-circuiting step), and the base material 17 and the welding wire 18 are first short-circuited (time point C). Is detected. Further, after the short circuit, a short circuit opening current for applying a short circuit is applied to the welding wire 18, whereby an arc is generated between the base material 17 and the welding wire 18, and the base material 17 and the welding wire 18 are short circuited. Is opened (first short-circuit opening step). The time point at which the short circuit is opened is detected, or the time point (time point D) at which the short circuit is opened and the current after the short circuit is opened reaches a predetermined value as the time point when the short circuit opening is stabilized. If the first distance WD1 between the tip of the welding wire 18 and the base material 17 in the tip position control period Tb is not adversely affected by a short circuit or the like, the average is obtained after detecting the time of short circuit (time C). The feeding of the welding wire 18 may be continued until the feeding speed Wa becomes zero. Alternatively, when the time point of short-circuiting (time point C) is detected, the feeding of the welding wire 18 may be stopped.

  The tip position control period Tb of the welding wire 18 is started after time D immediately after the detection of the short circuit opening. Specifically, the tip position control period Tb is started after the short circuit is opened just before the time point D and the current after the short circuit is opened reaches a predetermined value. If there is no problem such as an unintended short circuit, the tip position control period Tb may be started immediately after the short circuit is opened. In the tip position control period Tb, by passing a predetermined current Ic1 (first current) through the welding wire 18, the welding wire 18 where the arc is generated is heated and the tip starts to melt further. By adjusting the time for flowing the first current Ic1 to a predetermined time T1 (first time), the melting amount of the tip of the welding wire 18 is determined, and as a result, the tip of the welding wire 18 is formed into a ball shape. At the same time, the distance between the tip of the welding wire 18 and the base material 17 is adjusted to a desired first distance WD1 in a separated state (wire tip position control step).

  After the end position control period Tb ends, the welding current I becomes 0 and the cooling period Tn starts. During the cooling period Tn, the distance between the tip of the welding wire 18 and the base material 17 is maintained at the first distance WD1. During the cooling period Tn, the welding wire 18 and the base material 17 are fixed to each other, and the welding wire 18 to the base material 17 are fixed. In this state, after the cooling period Tn, the next welding cycle is continuously started on the same weld bead. That is, the welding output is controlled by the short-circuit welding control unit 11 under the conditions set by the short-circuit welding setting unit 23 from the time point Ed at which the welding wire 18 is forwardly fed and the occurrence of a short circuit between the welding wire 18 and the base material 17 is detected. Then, the first short-circuit welding is performed. Thereby, before the cooling period Tn, the next welding on the same welding bead is performed by separating the welding wire 18 and the base material 17 by a predetermined first distance WD1 so as to be as small as possible. At the start of the cycle, the distance to the short circuit between the welding wire 18 of the first short circuit welding and the base material 17 is shortened and stabilized, the loss of the start of the short circuit is suppressed, and the welding cycle Pc is further stabilized. And a stable scaly bead with a beautiful appearance with clear waviness can be realized.

  In the present embodiment, the first distance WD1 is adjusted to be about 1.5 mm to 3 mm, preferably about 2 mm, the first current Ic1 is about 30 A, and the first time T1 is about 4 msec. It is.

In the present embodiment, the average feed speed Wa of the welding wire 18 is decelerated at the average acceleration α1 from the second short-circuit welding period Tse1 to the tip position control period Tb, and the average deceleration acceleration α1 is 8.3 m. It is set in the range of / s ^{2 to} 33.3 m / s ² . ^Preferably, it is set in the range of 13.3m / ^{s 2} ~33.3m / s 2 typically be set at 16.7 m / ^{s 2.}

  By setting the average deceleration acceleration α1 within the above range, the transition from the high heat input pulse welding period Tp to the cooling period Tn in which the welding current I is turned off is performed quickly, and the heat input balance at the welding location is improved. It is possible to adjust more clearly and to stabilize the rising at the start of arc generation. Moreover, the heat input difference in a welding location can be enlarged and the external appearance of a welding location can be made favorable. In particular, when a plurality of scaly beads are continuously formed and arranged on the base material 17, a scaly bead having a beautiful appearance with a clear wave pattern can be realized. Moreover, the welding tact can be further increased.

  If the average deceleration acceleration α1 becomes too large, the welding wire 18 may be excessively pushed into the base material 17 when the short circuit is detected at the time point C shown in FIG. 4, and the welding wire 18 and the base material 17 are temporarily short-circuited. After that, the first distance WD1, which is the distance between the tip of the welding wire 18 and the base material 17, which is adjusted in the tip position control period Tb, becomes unstable. In addition, if the average deceleration acceleration α1 becomes too small, the transition from the heat input pulse welding period Tp to the cooling period Tn where the welding current is turned off becomes too slow, and the heat input balance at the welding point becomes too gentle. The scale beads may become unclear. In consideration of the above, the range of the average deceleration acceleration α1 is set.

[About burnback control]
When welding at a predetermined welding point or welding locus is completed, arc welding is ended by a welding end signal (not shown). If necessary, the welding wire 18 and the torch are moved to the next welding point after the end of arc welding. Thus, when arc welding is completed, it is necessary to leave a predetermined distance in advance between the welding wire 18 and the base material 17 so as not to be fixed. For this reason, at the end of arc welding, the welding wire 18 and the torch can be stably moved to the next welding point, which is a welding start point at a position different from that on the welding bead at the end of arc welding after the end of arc welding. As described above, the burnback control for separating the welding wire 18 and the base material 17 by a predetermined distance is performed. In the burnback control, similar to the above-described wire tip position control, a predetermined current is passed through the welding wire 18 for a predetermined time to melt the tip of the welding wire 18 and change its shape into a ball shape to form droplets. In addition, the distance between the welding wire 18 and the base material 17 is adjusted.

  FIG. 5 shows various output waveforms at the end of arc welding. In addition, in FIG. 5, the time change waveform of the welding voltage V and the welding current I is shown similarly to FIGS. In addition, at the time of the end of arc welding in which a welding end signal is output, instead of the second short-circuit welding period Tse1 following the pulse welding period Tp having a high heat input shown in FIGS. A third short-circuit welding period Tse2 in which the arc state and the short-circuit state are alternately provided while the average feed speed is gradually attenuated while repeating the reverse feed and the average values of the welding current I and the welding voltage V are lowered is provided. .

  For the third short-circuit welding period Tse2, the preparation period Ta, and the tip position control period Tb, the wire feed speed Wa is shown as an average speed in order to facilitate the explanation as in FIG. Further, during this period, it is preferable to gradually attenuate the average feeding speed while repeating normal feeding and reverse feeding of the welding wire 18 to feed the welding wire. May be gradually reduced.

  When a welding end signal is output from the control switching unit 9 to the output control unit 10 (time point E), as shown in FIG. 5, the average feed speed Wa of the welding wire 18 decreases monotonously as described above.

  When the average feed speed Wa becomes equal to or lower than a predetermined threshold (time point F), a preparation period Td for forming the tip of the welding wire 18 into a ball shape is started. In the preparation period Td, when the welding wire 18 is forwardly fed, the base material 17 and the welding wire 18 are short-circuited (second short-circuiting step), and the base material 17 and the welding wire 18 are first short-circuited (time point G). Is detected. Further, after the short circuit, a short circuit opening current for applying a short circuit is applied to the welding wire 18, whereby an arc is generated between the base material 17 and the welding wire 18, and the base material 17 and the welding wire 18 are short circuited. Is opened (second short-circuit opening step). The time point at which the short circuit is opened is detected, or the time point (time point H) at which the short circuit is opened and the current after the short circuit is opened reaches a predetermined value as the time point when the short circuit opening is stabilized.

  The burnback control period Te is started after time H immediately after the detection of the short circuit opening. Specifically, the burnback control period Te is started after the short circuit is opened just before the time point H and the current after the short circuit is opened reaches a predetermined value. If there is no problem such as an unintended short circuit, the burnback control period Te may be started immediately after the time when the short circuit is opened. In the burnback control period Te, by passing a predetermined current Ic2 through the welding wire 18, the welding wire 18 where the arc is generated is heated and the tip starts to melt further. By adjusting the time for supplying the current Ic2 to a predetermined time T2 (second time), the melting amount of the tip of the welding wire 18 is determined. As a result, the tip of the welding wire 18 is formed into a ball shape, The distance between the tip of the welding wire 18 and the base material 17 is adjusted to a second value WD2 that is a desired value (burnback control step).

  After the end of the burnback control period Te, the welding current I becomes 0, and the welding wire 18 and the torch can be stably moved to the next welding point that is a welding start point different from the position on the weld bead at the end of welding. In this way, arc welding is completely completed. When the next welding starts after the end of arc welding, the position of the torch is set to a predetermined value, so the distance between the tip of the welding wire 18 and the base material 17 is maintained at the second distance WD2. In this state, the next arc welding is started.

  In the present embodiment, the second distance WD2 is adjusted to be about 5 mm, the second current Ic2 is about 50 A, and the second time T2 is about 50 msec. That is, the second distance WD2 in the burnback control step is adjusted to be longer than the first distance WD in the tip position control step. In the example shown in FIGS. 4 and 5, the second current Ic2 is adjusted to be larger than the first current Ic1, and the second time T2 is adjusted to be longer than the first time T1. However, the setting of the first and second currents IC1 and IC2 and the first and second times T1 and T2 is not particularly limited to this. In short, the second distance WD2 only needs to be longer than the first distance WD1. Specifically, the welding wire 18 is used in the burnback control step rather than the electric power applied to the welding wire 18 in the tip position control step. It is sufficient to increase the power applied to the. These electric powers are determined by the product of the welding current I, the welding voltage V and the time in each step. Therefore, this product may be made larger in the burnback control step than in the tip position control step. In addition to the above, for example, the first current IC1 and the second current IC2 may be set to the same value, and the second time T2 may be adjusted to be longer than the first time T1, The first time T1 and the second time T2 may be set to the same value, and the second current IC2 may be adjusted to be larger than the first current IC1. In addition, in the state where the short circuit between the welding wire 18 and the base material 17 is opened, if the welding current I is excessively increased, spatter is generated, and the appearance of the welded portion is impaired, or a welding failure occurs. It is not preferable that the second current Ic2 becomes too large. Therefore, in order to avoid such a problem, the second current Ic2 may be made closer to the first current Ic1.

Further, in the present embodiment, the average feed speed Wa of the welding wire 18 is decelerated at the average acceleration α2 from the third short-circuit welding period Tse2 to the time point shown in FIG. 5, and this average deceleration acceleration α2 is 0.8 m. It is set within the range of / s ^{2 to 5} m / s ² . Typically, it is set at 1.7 m / s ² .

  By setting the average deceleration acceleration α2 within the above range, it is less likely to cause welding disturbance due to sudden deceleration, and the burnback process is executed reliably so that welding from the next welding start point is performed smoothly. be able to. Further, since the degree of cooling at the end of the weld bead, which is the end point of welding, is relatively large, the end of the weld bead can be adjusted by gradually reducing the amount of heat input to the base material 17 and adjusting the amount of heat input. The appearance design property of a bead can be improved by suppressing the dent (crater) in a part.

  In the present embodiment, the average deceleration acceleration α1 of the welding wire 18 before the start of the tip position control is set to have an absolute value larger than the average deceleration acceleration α2 of the welding wire 18 before the end of welding. It is not particularly limited to this. For example, the absolute value of the average deceleration acceleration α1 can be set to the average deceleration when it is desired to smoothly form a ball-shaped droplet at the tip of the welding wire 18 and to smoothly start the arc rather than the welding speed or scale-shaped bead appearance. You may make it approximate the value of the acceleration α2. For example, α1 = α2 may be set. When importance is attached to the bead appearance, it is preferable to set the average deceleration acceleration α1 within the above-mentioned range, and to make the absolute value of the average deceleration acceleration α1 larger than the absolute value of the average deceleration acceleration α2.

[Effects]
As described above, the arc welding control method according to the present embodiment is provided after the welding current ON period Ton in which the predetermined welding current I flows through the welding wire 18 and the welding current ON period Ton. Arc welding is performed by periodically repeating the welding current on period Ton and the welding current off period Toff with the sum of the welding current off period Toff in which the current I does not flow as a welding period Tc. In a preparation period Ta just before the end of the welding current ON period Ton, the welding wire 18 is short-circuited with the base material 17 (first short-circuiting step). Further, the short circuit between the welding wire 18 and the base material 17 is opened (first short circuit opening step).

  In the tip position control period Tb of the welding wire 18 following the first short-circuiting step and the first short-circuit opening step, the first current Ic1 is supplied to the welding wire 18 at the first time T1, so that the welding wire 18 The tip is melted to change its shape, and the distance between the tip of the welding wire 18 and the base material 17 is adjusted to be the first distance WD1 (wire tip position control step). Furthermore, a cooling period Tn as a welding current off period Toff is started after the end of the wire tip position control step.

  According to the present embodiment, the first current Ic1 is supplied to the welding wire 18 at the first time T1 during the transition from the welding current on period Ton to the cooling period Tn (welding current off period Toff). The melting amount at the tip of the welding wire 18 can be easily controlled. This makes it easy to adjust the first distance WD1, which is the distance between the welding wire 18 and the base material 17. Further, by adjusting the distance between the tip of the welding wire 18 and the base material 17 to a first distance WD1 which is a desired value, and making the distance between the welding wire 18 and the base material 17 as close as possible, after the end of the cooling period Tn. On the same weld bead, it is possible to continuously stabilize the rising at the start of arc generation in the next welding cycle. In addition, since arc welding is performed with the welding current ON period Ton and the welding current OFF period Toff as one welding cycle Tc, the heat input difference at the welding point can be increased, and the appearance of the welding point can be improved. . In particular, when a plurality of scaly beads are continuously arranged on the base material 17, a scaly bead having a beautiful appearance with a clear wave can be realized.

  In addition, after the first short-circuit step, a first short-circuit release step is provided, and by starting the tip position control period Tb from the short-circuit release time point D, the length of the tip of the welding wire 18 melted and retracted is directly Therefore, the distance between the welding wire 18 and the base material 17 can be set to the first WD1, and the adjustment accuracy of the first distance WD1 can be improved.

  Moreover, the arc welding control method according to the present embodiment causes the welding wire 18 to be short-circuited with the base material 17 at the end of arc welding (second short-circuiting step). Further, the short circuit between the welding wire 18 and the base material 17 is opened (second short circuit opening step). In the burn-back control period Te following the second short-circuit step and the second short-circuit release step, the second current Ic2 is supplied to the welding wire 18 at the second time T2, so that the tip of the welding wire 18 has a ball shape. And the distance between the tip of the welding wire 18 and the base material 17 is adjusted to the second distance WD2 (burnback control step). Further, the electric power applied to the welding wire 18 in the burnback control step is larger than the electric power applied to the welding wire 18 in the wire tip position control step, and the first distance WD1 is shorter than the second distance WD2.

  According to this embodiment, the power applied to the welding wire 18 in the burnback control step is larger than the power applied to the welding wire 18 in the wire tip position control step, so that the tip of the welding wire 18 is increased. Can be made larger than the melting amount in the wire tip position control step. This makes it easy to adjust the second distance WD2 between the welding wire 18 and the base material 17 to be longer than the first distance WD1. Further, by adjusting the distance between the tip of the welding wire 18 and the base material 17 to be the second distance WD2, the welding wire 18 and the base material 17 are fixed when the arc welding is finished. Can be prevented. Moreover, when the surface of the molten pool formed in the base material 17 vibrates immediately after completion of arc welding, the welding wire 18 unintentionally contacts the molten pool and spatter is generated, or welding at the end of welding is performed. When the welding wire 18 moves to the next welding point which is a welding start point at a position different from that on the bead, it is possible to prevent the appearance of the welded portion from being damaged by contacting the base material 17 or the molten pool.

  Further, by adjusting the distance between the tip of the welding wire 18 and the base material 17 to the second distance WD2 which is a desired value, the next arc welding is performed with the tip of the welding wire 18 in contact with the base material 17. The start (touch start) can be reliably avoided and the arc start can be performed smoothly.

  Further, after the second short-circuit step, a second short-circuit release step is provided, and by starting the burnback control period Te from the short-circuit release time point H, the length of the welding wire 18 melted and retracted directly is directly Thus, the second distance WD2 that is the distance between the welding wire 18 and the base material 17 can be set, and the adjustment accuracy of the second distance WD2 can be improved.

  Further, the welding speed can be increased by making the first time T1 in the wire tip position control step shorter than the second time T2 in the burnback control step. Further, the appearance of the welded portion can be improved. This will be further described with reference to FIGS.

  FIG. 6 shows various output waveforms during the continuous welding cycle according to the present embodiment, and FIG. 7 shows various output waveforms during the continuous welding cycle for comparison. 6 and 7 show the time-varying waveforms of the welding voltage V and the welding current I as in FIGS. Note that the wire feed speed W is shown as an average speed in order to facilitate the explanation as in FIG. Note that the wire feeding speed Wa that attenuates from the pulse welding period Tp toward the tip position control period Tb attenuates the average feeding speed while repeating normal feeding and reverse feeding of the welding wire 18 to feed the welding wire. Although it is preferable to perform this, the feeding speed of the welding wire 18 may be reduced during normal feeding. Further, it is preferable that the average feed speed of the wire feed speed Wa that attenuates from the pulse welding period Tp toward the tip position control period Tb is steeper. By making it steep, the threshold value at which the preparation period Ta starts (time point B shown in FIG. 4) can be quickly reached, and the welding cycle Tc can be made compact while ensuring the tip position control period Tb, and welding can be performed. Tact can be suppressed. In the arc welding shown in FIG. 7, in the wire tip position control step, the first distance WD1, the first current Ic1, and the first time T1 are the second distance WD2 and the second distance WD2 in the burnback control step. The current Ic2 and the second time T2 are adjusted to be approximately the same. That is, the first distance WD1 is adjusted to be about 5 mm, the first current Ic1 is adjusted to about 50 A, and the first time T1 is adjusted to about 50 msec.

  According to the arc welding of the present embodiment shown in FIG. 6, the no-load detection period Tf can be about 30 msec, whereas according to the arc welding shown in FIG. 7, the no-load detection period Tf is about 60 msec, which is about 2 It is twice as long. Here, as shown in FIG. 2, the no-load detection period Tf is a period from a welding start instruction time point Wst to a time point Ed at which a short circuit between the welding wire 18 and the base material 17 is detected. This is a period during which the no-load voltage V1 is generated. Thus, in the example shown in FIG. 7, the no-load detection period Tf becomes longer because the wire feed speed at the start of welding in the first short-circuit welding period Tss is constant at W1, whereas the cooling period Tn This is because the first distance WD1 between the tip of the welding wire 18 and the base material 17 is 5 mm in the case of FIG. 7 and is longer than 2 mm in the case of FIG.

  In the arc welding control in the present embodiment, the no-load detection period Tf is included in the first short-circuit welding period Tss and is not included in the cooling period Tn. Therefore, as shown in FIG. 7, when the no-load detection period Tf becomes longer, the period in which no arc is generated following the cooling period Tn becomes longer, and the substantial cooling period of the welding wire 18 becomes longer. As a result, the difference in heat input to the welded portion is different from the designed value, and a desired appearance cannot be obtained. Moreover, if the no-load detection period Tf becomes longer, the welding current ON period Ton becomes longer than the set value, and the welding cycle Tc becomes longer. For this reason, the welding time in one welding point becomes long, and the whole welding speed will fall.

  On the other hand, according to the present embodiment, by setting the first time T1 in the wire tip position control step to be shorter than the second time T2 in the burnback control step, as shown in FIG. It is possible to prevent the detection period Tf from becoming long and increase the welding speed. Further, the appearance of the welded portion can be improved. Further, in the wire tip position control step and the burnback control step, the current flowing through the welding wire 18 and the time during which the current flows and the distance between the welding wire 18 and the base material 17 are individually controlled, so that the welding speed is controlled. To improve the appearance of the welded portion and prevent the welding wire 18 and the base material 17 from adhering at the end of arc welding. As a result, high-quality and stable arc welding can be performed over the entire predetermined welding trajectory.

  In addition, in this embodiment, although the wire diameter of the welding wire 18 was about 1.1 mm-1.3 mm, it is not specifically limited to this. In addition, the first distance WD1 in the wire tip position control step and the second distance WD2 in the burnback control step can be appropriately changed depending on the material and surface shape of the base material 17, the required welding time, and the like.

(Embodiment 2)
FIG. 8 is a diagram showing various output waveforms at the time of arc welding according to the present embodiment. In the arc welding in which the first short-circuit welding period Tss, the pulse welding period Tp, and the cooling period Tn are repeated, the feeding speed W and the welding are shown. The time change of the voltage V, the welding current I, and the droplet transfer state D at the tip of the welding wire 18 is shown. Note that a preparation period Ta for controlling the tip position of the welding wire 18 between the pulse welding period Tp and the cooling period Tn and a tip position control period Tb of the welding wire 18 are not shown.

  The method shown in this embodiment is different from the method shown in Embodiment 1 in that the second short-circuit welding period Tse1 is omitted. In the present embodiment, after the end of the pulse welding period Tp, as shown in FIG. 4, a preparation period Ta and a tip position control period Tb of the welding wire 18 are provided, and the welding wire 18 is provided in the tip position control period Tb. On the other hand, by supplying the first current Ic1 at the first time T1, the tip of the welding wire 18 is melted to change its shape, and the distance between the tip of the welding wire 18 and the base material 17 is the first. The distance is adjusted to be WD1. Further, as shown in FIG. 5, a preparation period Td and a burnback control period Te are provided at the end of arc welding in which arc welding is terminated by a welding end signal (not shown). In the burnback control period Te, a welding wire is provided. By supplying the second current Ic2 to the second wire 18 at the second time T2, the tip of the welding wire 18 is formed into a ball shape, and the distance between the tip of the welding wire 18 and the base material 17 is the second. The distance is adjusted to be WD2.

  In the method shown in the first embodiment, by setting the second short-circuit welding period Tse1 to a predetermined value, it is possible to reduce the amount of heat input to the base material 17 and to adjust the heat input balance at the welded location, By reducing the number of generated pits, the appearance design of the scaly bead can be improved.

  However, also by the method shown in the present embodiment, the rising at the start of arc generation can be stabilized, as in the method shown in the first embodiment. Moreover, the heat input difference in a welding location can be enlarged and the external appearance of a welding location can be made favorable. In particular, when a plurality of scaly beads are continuously arranged on the base material 17, a scaly bead having a beautiful appearance with a clear wave can be realized. Furthermore, the welding speed can be increased.

(Other embodiments)
In the first and second embodiments, by providing the burnback control period Te and supplying predetermined power to the welding wire 18, the distance between the tip of the welding wire 18 and the base material 17 is the second distance. Although adjusted so as to be WD2, the distance between the tip of the welding wire 18 and the base material 17 may be adjusted by other methods. For example, at the end of arc welding, following the second short circuit step and the second short circuit release step described above, in other words, after the second short circuit release step or during the second short circuit release step, You may adjust so that the distance of the front-end | tip of the welding wire 18 and the preform | base_material 17 may become 2nd distance WD2 by reversely feeding 18. In addition, short circuit opening can be accelerated | stimulated by sending back the welding wire 18 during a short circuit opening step.

  With this method, the distance between the tip of the welding wire 18 and the base material 17 can be adjusted in a short time. However, when the second distance WD2 is adjusted by reversely feeding the welding wire 18, a feeding error may occur due to frictional resistance or slippage of the wire feeding. In the burnback control step, the accuracy of adjusting the distance is improved by providing the burnback control period Te and adjusting the second distance WD2 by the electric power applied to the welding wire 18. Note that the second distance WD2 is used in combination with both reverse feeding of the welding wire 18 at the end of arc welding and melting of the tip by applying a predetermined electric power to the welding wire 18 in the burnback control period Te. May be adjusted. In addition, the present invention is not limited to this, and each of the constituent elements and steps described in the above embodiments can be combined to form a new embodiment.

  The arc welding control method according to the present invention stabilizes the rising at the start of arc generation and can improve the appearance of the welded portion, so that arc welding that forms scaly beads, for example, frames for bicycles, motorcycles, automobiles, etc. This is useful when applied to arc welding to the like.

1 Input power 2 Main transformer (transformer)
3 Primary side rectification part 4 Switching part 5 DCL (reactor)
6 Secondary side rectification unit 7 Welding current detection unit 8 Welding voltage detection unit 9 Control switching unit 10 Output control unit 11 Short-circuit welding control unit 12 Pulse welding control unit 13 Wire feed speed control unit 14 Wire feed speed detection unit 15 Calculation Unit 16 Arc welding device 17 Base material 18 Welding wire 19 Arc 20 Welding tip 21 Wire feeding unit 22 Welding condition setting unit 23 Short-circuit welding setting unit 24 Pulse welding setting unit 25 Cooling period setting unit

Claims (12)

Arc welding is performed with a welding period as a sum of a welding current on period in which a predetermined welding current flows in the welding wire and a welding current off period in which the welding current does not flow in the welding wire. An arc welding control method comprising:
A first short-circuiting step for short-circuiting the welding wire with a base material immediately before the end of the welding current ON period;
After the first short-circuiting step, by supplying a first current to the welding wire for a first time, the tip shape of the welding wire is changed, and the tip of the welding wire and the base material are changed. A wire tip position control step for adjusting the distance so as to be the first distance,
The arc welding control method, wherein the welding current off period is started after the end of the wire tip position is controlled. In the arc welding control method according to claim 1,
After the first short circuit step, further comprising a first short circuit opening step for opening a short circuit between the welding wire and the base material,
An arc welding control method, wherein the wire tip position control step is performed after completion of the first short circuit opening step. In the arc welding control method according to claim 1 or 2,
A second short-circuit step for short-circuiting the welding wire with the base material at the end of arc welding;
After the second short circuit step, further comprising a second short circuit opening step for opening a short circuit between the welding wire and the base material, In the arc welding control method according to claim 1 or 2,
A second short-circuit step for short-circuiting the welding wire with the base material at the end of arc welding;
After the second short-circuit step, by supplying a second current to the welding wire for a second time, the tip of the welding wire is formed into a ball shape, and the tip of the welding wire and the mother A burnback control step for adjusting the distance to the material to be the second distance,
The arc welding control method, wherein the first distance is shorter than the second distance. In the arc welding control method according to claim 4,
An arc welding control method, wherein the electric power applied to the welding wire in the burnback control step is larger than the electric power applied to the welding wire in the wire tip position control step. In the arc welding control method according to claim 5,
The first current is the same value as the second current, and the first time is shorter than the second time, or the second current is greater than the first current, and The first time is the same value as the second time, or the second current is larger than the first current, and the first time is shorter than the second time. Arc welding control method. In the arc welding control method according to any one of claims 1 to 6,
In the welding current ON period, the first low heat input welding with a low heat input to the base material and the high heat input welding with a high heat input to the base material compared to the first low heat input welding in this order. An arc welding control method characterized by being performed. In the arc welding control method according to claim 7,
The first low heat input welding is short-circuit welding, and the high heat input welding is pulse welding. In the arc welding control method according to claim 7,
An arc welding control method, wherein after the high heat input welding, second low heat input welding, in which heat input to the base material is lower than that of the high heat input welding, is further performed. In the arc welding control method according to claim 9,
The first and second low heat input weldings are short-circuit weldings, and the high heat input weldings are pulse weldings. In the arc welding control method according to claim 8 or 10,
In the short-circuit welding, by alternately repeating forward and reverse feeding of the welding wire with respect to the base material, an arc is generated between the base material and the welding wire, the base material, and the base material. The welding wire and the short-circuited state are repeated alternately.
In the pulse welding, the welding wire is sent to the base material at a constant wire feed speed, and a peak current and a base current are alternately passed through the welding wire, whereby the base material, the welding wire, An arc welding control method characterized by performing an arc between the two. In the arc welding control method according to any one of claims 1 to 11,
An arc welding control method comprising forming a plurality of scaly beads continuously arranged on the base material.