Pulse arc welding control method

Abstract

To achieve an excellent welding quality by regularly maintaining a one-pulse period one droplet transfer state even when a welding state varies, in consumable electrode pulse-arc welding.SOLUTION: In a pulse-arc welding control method, a welding wire is fed, peak rising currents Iu that rise from a value of base currents Ib to a value of peak currents Ip are passed during a peak rising period of time Tu, the peak currents Ip are passed during a peak period of time Tp, peak falling currents Ik that fall from the value of the peak currents Ip to the value of the base currents Ib are passed during a peak falling period of time Tk, and the base currents Ib are passed during the base period of time Tb. Changing from a backward feeding peak value Wr to a forward feeding peak value Ws is started at a start time point of the peak rising period of time Tu and changing from the forward feeding peak value Ws to the backward feeding peak value Wr is started at a start time point of the peak falling period of time Tk, at feeding speed Fw of the welding wire. The forward feeding peak value Ws and the backward feeding peak value Wr are changed based on an average value of welding voltages.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a pulse arc welding control method for feeding a welding wire to weld. [Background technology]

[0002] Pulse arc welding, which involves feeding a welding wire to weld, is widely used in welding steel and other materials. In pulse arc welding, the welding wire is fed, and a peak-rise current is applied during the peak-rise period, increasing from the base current value to the peak current value. The peak current is applied during the peak period, and a peak-fall current is applied during the peak-fall period, decreasing from the peak current value to the base current value. The base current is applied during the base period, and these current applications are repeated as one pulse cycle to perform welding. In pulse arc welding, by achieving one droplet transfer per pulse cycle, spatter is reduced and a beautiful bead appearance can be achieved.

[0003] In the invention of Patent Document 1, during a predetermined period from a first point in time during the peak period to a second point in time during the base period, the welding wire feed speed is set to be slower than the feed speed at the rising point of the peak current, or the welding wire is fed in a reverse direction, i.e., in a direction away from the workpiece to be welded. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6123069 Summary of the Invention [Problem to be solved by the invention]

[0005] In pulsed arc welding, it is important to always maintain a droplet transfer state per pulse cycle in order to obtain good welding quality. However, in conventional pulsed arc welding, there is a problem that the droplet transfer state deviates from the state of one droplet transfer per pulse cycle due to fluctuations in the welding state, resulting in poor welding quality.

[0006] Therefore, an object of the present invention is to provide a pulsed arc welding control method capable of always maintaining a droplet transfer state per pulse cycle and obtaining good welding quality even when the welding state fluctuates.

Means for Solving the Problems

[0007] In order to solve the above-described problems, the invention of claim 1 is feeding a welding wire, in a pulsed arc welding control method of repeatedly performing the above energization as one pulse cycle by energizing a peak rising current that rises from the value of the base current to the value of the peak current during the peak rising period, energizing the peak current during the peak period, energizing a peak falling current that falls from the value of the peak current to the value of the base current during the peak falling period, and energizing the base current during the base period, the welding wire repeatedly performs forward feeding and reverse feeding, and performs reverse feeding at least during the base period, changing the forward feeding peak value and the reverse feeding peak value based on the average value of the welding voltage, which is a pulsed arc welding control method characterized by the above.

[0008] The invention of claim 2 is changing the forward feeding peak value and the reverse feeding peak value based on the error between the average value of the welding voltage and the set value of the welding voltage, which is the pulsed arc welding control method according to claim 1, characterized by the above.

[0009] The invention of claim 3 is changing the forward feeding peak value and the reverse feeding peak value so that the average value of the feeding speed of the welding wire becomes a predetermined value, The pulsed arc welding control method according to claim 1 or 2, characterized in that

[0010] The invention according to claim 4 The feeding speed of the welding wire Starts to change from the peak value of the reverse feeding to the peak value of the forward feeding at the start of the peak rising period, Starts to change from the peak value of the forward feeding to the peak value of the reverse feeding at the start of the peak falling period. The pulsed arc welding control method according to claim 1 or 2, characterized in that

[0011] The invention according to claim 5 The change period from the peak value of the forward feeding to the peak value of the reverse feeding is less than or equal to the peak falling period. The pulsed arc welding control method according to claim 4, characterized in that

Advantages of the Invention

[0012] According to the pulsed arc welding control method of the present invention, even if the welding state fluctuates, a good welding quality can be obtained by always maintaining a droplet transfer state per pulse cycle.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Embodiments for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0015] 1 is a block diagram of a welding apparatus for carrying out a pulse arc welding control method according to an embodiment of the present invention. The welding apparatus is mainly composed of a welding power source PS, a robot control device RC, a robot (not shown), etc., all of which are enclosed by dashed lines. Each block will be described below with reference to the diagram.

[0016] The welding power source PS consists of the following blocks:

[0017] The power control circuit MC receives an AC commercial power supply (not shown) such as a three-phase 200V, performs output control such as inverter control in accordance with a drive signal Dv described below, and outputs a welding voltage Vw and welding current Iw suitable for welding. Although not shown, the power control circuit MC includes a primary rectifier circuit that rectifies the AC commercial power supply, a capacitor that smoothes the rectified DC, an inverter circuit that converts the smoothed DC into high-frequency AC in accordance with the drive signal Dv, an inverter transformer that steps down the high-frequency AC to a voltage value suitable for welding, and a secondary rectifier circuit that rectifies the stepped-down high-frequency AC.

[0018] The reactor WL is inserted between the positive output of the power control circuit MC and the welding torch 4, and smoothes the output of the power control circuit MC.

[0019] The feed motor WM is driven to rotate by a feed control signal Fc, which will be described later. The welding wire 1 is fed forward and backward through the welding torch 4 at a feed speed Fw by the rotation of a feed roll 5 connected to the feed motor WM, and an arc 3 is generated between the welding wire 1 and the base material 2. The feed motor WM and the welding torch 4 are mounted on a robot. A welding voltage Vw is applied between a power feed tip (not shown) in the welding torch 4 and the base material 2, and a welding current Iw flows.

[0020] The welding voltage detection circuit VD detects the welding voltage Vw and outputs a welding voltage detection signal Vd. The welding voltage averaging circuit VAV averages the welding voltage detection signal Vd (by passing it through a low-pass filter) and outputs a welding voltage average value signal Vav. The welding voltage setting circuit VR outputs a predetermined welding voltage setting signal Vr. The voltage error amplification circuit EV amplifies the error between the welding voltage setting signal Vr(+) and the welding voltage average value signal Vav(-) and outputs a voltage error amplification signal Ev.

[0021] The current modulation circuit IC receives the voltage error amplified signal Ev as an input, performs PI (proportional-integral) control or PID (proportional-integral-derivative) control, and outputs a peak current setting signal Ipr and a base current setting signal Ibr. This circuit performs current modulation control of the peak current setting signal Ipr and the base current setting signal Ibr so that the welding voltage average value signal Vav becomes equal to the welding voltage setting signal Vr. As a result, arc length control is performed so that the arc length is maintained at an appropriate value. It is also possible to perform current modulation control of only the peak current setting signal Ipr, and set the base current setting signal Ibr to a predetermined value.

[0022] The peak rise period setting circuit TUR outputs a predetermined peak rise period setting signal Tur. The peak period setting circuit TPR outputs a predetermined peak period setting signal Tpr. The peak fall period setting circuit TKR outputs a predetermined peak fall period setting signal Tkr. The base period setting circuit TBR outputs a predetermined base period setting signal Tbr.

[0023] The welding current setting circuit IR receives the peak rise period setting signal Tur, the peak period setting signal Tpr, the peak fall setting signal Tkr, the base period setting signal Tbr, the peak current setting signal Ipr, and the base current setting signal Ibr as inputs, performs the following processing, and outputs the welding current setting signal Ir and the timer signal Tm. 1) During the peak rising period Tu determined by the peak rising period setting signal Tur, output the timer signal Tm = 1, and output the peak rising current Iu that rises from the value of the base current setting signal Ibr to the value of the peak current setting signal Ipr as the welding current setting signal Ir. 2) Subsequently, during the peak period Tp determined by the peak period setting signal Tpr, output the timer signal Tm = 2, and output the peak current setting signal Ipr as the welding current setting signal Ir. 3) Subsequently, during the peak falling period Tk determined by the peak falling period setting signal Tkr, output the timer signal Tm = 3, and output the peak falling current Ik that falls from the value of the peak current setting signal Ipr to the value of the base current setting signal Ibr as the welding current setting signal Ir. 4) Subsequently, during the base period Tb determined by the base period setting signal Tbr, output the timer signal Tm = 4, and output the base current setting signal Ibr as the welding current setting signal Ir. 5) Repeat the above 1) to 4).

[0024] The forward peak value setting circuit WSR takes the above welding voltage average value signal Vav and the above welding voltage setting signal Vr as inputs, and performs either of the following processes 1) or 2), and outputs a positive forward peak value setting signal Wsr with a positive value. Process 1 When Vav ≥ Vt, Wsr = Ws0 + K·(Vav - Vt) When Vav < Vt, Wsr = Ws0 Here, Vt is a predetermined reference welding voltage value, Ws0 is the initial value of the forward peak value, and K is a constant. For example, if Vt = 35V, Ws0 = 50m / min, and K = 2. When (Vav - Vt) < 0V, Wsr = 50m / min. When (Vav - Vt) = 2V, Wsr = 50 + 2×2 = 54m / min. When (Vav - Vt) = 5V, Wsr = 50 + 2×5 = 60m / min. Therefore, the forward peak value changes based on the average welding voltage value. Process 2 When Vav ≧ Vr, Wsr = Ws0 + K·(Vav - Vr) When Vav < Vr, Wsr = Ws0 Here, Ws0 is the initial value of the forward peak value, and K is a constant. For example, if Ws0 = 50 m / min and K = 2.0, then When (Vav - Vr) < 0 V, Wsr = 50 m / min, When (Vav - Vr) = 2 V, Wsr = 50 + 2×2 = 54 m / min, When (Vav - Vr) = 5 V, Wsr = 50 + 2×5 = 60 m / min. Therefore, the forward peak value changes based on the error between the average welding voltage value and the set welding voltage value.

[0025] The average feed speed setting circuit FAR outputs a predetermined average feed speed setting signal Far. The average feed speed detection circuit FAD takes the feed speed setting signal Fr (described later) as an input, detects the average value of the feed speed setting signal Fr, and outputs an average feed speed detection signal Fad. The feed speed error amplification circuit EF amplifies the error between the above-mentioned average feed speed setting signal Far(+) and the above-mentioned average feed speed detection signal Fad(-), and outputs a feed speed error amplification signal Ef.

[0026] The reverse peak value setting circuit WRR takes the above-mentioned feed speed error amplification signal Ef as an input, performs variable speed control so that the value of the average feed speed detection signal Fad becomes equal to the value of the average feed speed setting signal Far, and outputs a reverse peak value setting signal Wsr with a negative value. With this circuit, when the forward peak value setting signal Wsr changes based on the average welding voltage signal Vav or the error between the average welding voltage signal Vav and the welding voltage setting signal Vr, the reverse peak value setting signal Wrr changes in conjunction with that change. Furthermore, even when the forward peak value setting signal Wsr changes as described above, the reverse peak value setting signal Wrr changes so that the average value of the feed speed always maintains a predetermined value (the value of the average feed speed setting signal Far).

[0027] The welding current detection circuit ID detects the welding current Iw and outputs a welding current detection signal Id. The current error amplifier circuit EI amplifies the error between the welding current setting signal Ir(+) and the welding current detection signal Id(-) and outputs a current error amplification signal Ei. The drive circuit DV receives the current error amplification signal Ei and an activation signal On from the robot control device RC (described later), and performs PWM modulation control based on the current error amplification signal Ei when the activation signal On is high (welding starts) and outputs a drive signal Dv for driving the inverter circuit in the power control circuit MC, but does not output the drive signal Dv when the activation signal On is low (welding stops).

[0028] The rising transition period setting circuit TFUR outputs a predetermined rising transition period setting signal Tfur. The value of the rising transition period setting signal Tfur is set to be equal to or less than the value of the peak rising period setting signal Tur. The falling transition period setting circuit TFKR outputs a predetermined falling transition period setting signal Tfkr. The value of the falling transition period setting signal Tfkr is set to be equal to or less than the value of the peak falling period setting signal Tkr.

[0029] The feeding speed setting circuit FR receives the forward feeding peak value setting signal Wsr, the reverse feeding peak value setting signal Wrr, the timer signal Tm, the rising change period setting signal Tfur, and the falling change period setting signal Tfkr as inputs, performs the following processing, and outputs a feeding speed setting signal Fr. 1) During the rising change period Tfu determined by the rising change period setting signal Tfur from the start of the peak rising period Tu of the timer signal Tm=1, the feeding speed setting signal Fr that changes from the value of the reverse feeding peak value setting signal Wrr to the value of the forward feeding peak value setting signal Wsr is output. 2) Subsequently, the forward feed peak value setting signal Wsr is output as the feed speed setting signal Fr. 3) Subsequently, during the falling change period Tfk determined by the falling change period setting signal Tfkr from the start of the peak falling period Tk of the timer signal Tm=3, the feeding speed setting signal Fr is output, which changes from the value of the forward feed peak value setting signal Wsr to the value of the reverse feed peak value setting signal Wrr. 4) Subsequently, the reverse feed peak value setting signal Wrr is output as the feed speed setting signal Fr. 5) Repeat steps 1) to 4) above.

[0030] The feed control circuit FC receives as input the feed speed setting signal Fr and a start signal On from the robot control device RC described later, and outputs a feed control signal Fc to the feed motor WM for feeding the welding wire 1 at the value of the feed speed setting signal Fr when the start signal On is at a high level (welding start), and outputs a feed control signal Fc to the feed motor WM for stopping feeding when the start signal On is at a low level.

[0031] The robot control device RC moves a robot (not shown) in accordance with a pre-taught work program, and outputs a start signal On to command the start or stop of welding.

[0032] 2 is a timing chart of signals in the welding device of FIG. 1, illustrating a pulse arc welding control method according to an embodiment of the present invention. (A) in FIG. 2 shows the change over time in welding current Iw, (B) in FIG. 2 shows the change over time in welding voltage Vw, and (C) in FIG. 2 shows the change over time in welding wire feed speed Fw. The operation of each signal will be explained below with reference to the diagram.

[0033] The feed speed Fw shown in Figure 1(C) indicates a forward feed state in which the material is fed forward in a direction toward the base material when it is a positive value above 0, and a reverse feed state in which the material is fed backward in a direction away from the base material when it is a negative value below 0.

[0034] During a predetermined peak rising period Tu from time t1 to t2, as shown in Fig. (A), a peak rising current Iu that rises from a base current Ib controlled by current modulation to a peak current Ip controlled by current modulation is energized, and as shown in Fig. (B), a peak rising voltage that rises from a base voltage Vb to a peak voltage Vp is applied between the welding wire and the base material. During a predetermined rising change period Tfu from time t1 to t11, as shown in Fig. (C), the feeding speed Fw changes from the value of the reverse feeding peak value Wr to the value of the forward feeding peak value Ws. The start point of the rising change period Tfu is synchronized with the start point of the peak rising period Tu. The rising change period Tfu is a period equal to or less than the peak rising period Tu. The above-mentioned peak rising period Tu is set by the peak rising period setting signal Tur in Fig. 1. The above-mentioned base current Ib is set by the base current setting signal Ibr in Fig. 1. The above-mentioned peak current Ip is set by the peak current setting signal Ipr in Fig. 1. The above-mentioned rising change period Tfu is set by the rising change period setting signal Tfur in Fig. 1. The above-mentioned reverse feeding peak value Wr is set by the reverse feeding peak value setting signal Wrr in Fig. 1. The above-mentioned forward feeding peak value Ws is set by the forward feeding peak value setting signal Wsr in Fig. 1.

[0035] During a predetermined peak period Tp from time t2 to t3, as shown in Fig. (A), a peak current Ip controlled by current modulation is energized, and as shown in Fig. (B), a peak voltage Vp is applied between the welding wire and the base material. During the period from time t11 to t3, as shown in Fig. (C), the feeding speed Fw becomes the value of the forward feeding peak value Ws. The above-mentioned peak period Tp is set by the peak period setting signal Tpr in Fig. 1.

[0036] During a predetermined peak decay period Tk from time t3 to t4, as shown in Fig. (A), a peak decay current Ik that descends from a peak current Ip controlled by current modulation to a base current Ib controlled by current modulation flows, and as shown in Fig. (B), a peak decay voltage that descends from a peak voltage Vp to a base voltage Vb is applied between the welding wire and the base material. During a predetermined decay change period Tfk from time t3 to t31, as shown in Fig. (C), the wire feed speed Fw changes from the value of the forward feed peak value Ws to the value of the reverse feed peak value Wr. The start point of the decay change period Tfk is synchronized with the start point of the peak decay period Tk. The decay change period Tfk is a period equal to or less than the peak decay period Tk. The above-mentioned peak decay period Tk is set by the peak decay period setting signal Tkr in Fig. 1. The above-mentioned decay change period Tfk is set by the decay change period setting signal Tfkr in Fig. 1

[0037] During a predetermined base period Tb from time t4 to t5, as shown in Fig. (A), a base current Ib controlled by current modulation flows, and as shown in Fig. (B), a base voltage Vb is applied between the welding wire and the base material. During the period from time t31 to t5, as shown in Fig. (C), the wire feed speed Fw becomes the value of the reverse feed peak value Wr. Therefore, at least during the base period Tb, the welding wire is fed in reverse. The above-mentioned base period Tb is set by the base period setting signal Tbr in Fig. 1

[0038] The above-mentioned forward feed peak value Ws is set by the forward feed peak value setting circuit WSR in Fig. 1 and changes based on the average value of the welding voltage or the error between the average value of the welding voltage and the welding voltage set value. The above-mentioned reverse feed peak value Wr is set by the reverse feed peak value setting circuit WRR in Fig. 1 and changes so that the average value of the wire feed speed becomes a predetermined value in conjunction with the change in the forward feed peak value Ws

[0039] Numerical examples of the above parameters are shown below Tu = 1 ms, Tp = 1 ms, Tk = 1 ms, Tb = 3 ms Ip = 350 - 450 A, Ib = 50 - 150 A Tfu = 0.5 - 1 ms, Tfk = 0.5 - 1 ms Ws = 50 - 60 m / min, Wr = -30 - -40 m / min

[0040] Next, the effects of this embodiment will be described. According to this embodiment, in a pulsed arc welding control method in which a welding wire is fed, a peak rising current that rises from the value of the base current to the value of the peak current is energized during the peak rising period, the peak current is energized during the peak period, a peak falling current that falls from the value of the peak current to the value of the base current is energized during the peak falling period, and the base current is energized during the base period, and these energizations are repeated as one pulse cycle for welding. The welding wire repeats forward feeding and reverse feeding, and is reverse fed at least during the base period, and the peak value of forward feeding and the peak value of reverse feeding are changed based on the average value of the welding voltage. By energizing the peak current during the peak period, a molten droplet is formed at the tip of the welding wire. During the subsequent base period, by reverse feeding the welding wire, an upward force can be continuously applied to the molten droplet during the base period, so that the molten droplet can be reliably transferred to the molten pool. Furthermore, when the distance between the power supply tip and the base material (wire protruding length) becomes long, the heating due to Joule heat in the wire protruding portion becomes large, and the formed molten droplet becomes too large. When the molten droplet becomes too large, it becomes difficult to detach the molten droplet during one pulse cycle. In this embodiment, it is detected based on the average value of the welding voltage that the distance between the power supply tip and the base material has become long, and the absolute values of the peak values of forward feeding and reverse feeding are changed to increase. By doing so, the upward force acting on the molten droplet can be increased, so that a state of transferring one molten droplet per pulse cycle can be realized. As a result, even if the welding state fluctuates, a state of transferring one molten droplet per pulse cycle can always be maintained, so that good welding quality can be obtained.

[0041] More preferably, according to this embodiment, the peak value of the forward feed and the peak value of the reverse feed are changed based on the error between the average welding voltage and the set welding voltage. In this embodiment, an increase in the distance between the power feed tip and the base metal is detected based on the error between the average welding voltage and the set welding voltage, and the absolute values of the peak values of the forward feed and the reverse feed are changed to increase. In this way, the upward force acting on the droplet can be increased, thereby achieving a one droplet transfer per one pulse period.

[0042] More preferably, according to this embodiment, the peak value of the forward feed and the peak value of the reverse feed are changed so that the average value of the welding wire feed rate is a predetermined value. In this way, even if the peak values of the forward feed and the reverse feed change as the distance between the power feed tip and the base metal increases, the average value of the feed rate can be maintained at a predetermined value. As a result, the bead appearance and penetration depth can be made uniform, thereby improving the welding quality.

[0043] More preferably, according to this embodiment, the welding wire feed speed starts changing from its peak value in the reverse feed to its peak value in the forward feed at the start of the peak rise period, and starts changing from its peak value in the forward feed to its peak value in the reverse feed at the start of the peak fall period. By synchronizing the start of the peak rise period with the start of the change from the peak value in the reverse feed to the peak value in the forward feed, droplets of appropriate size can be reliably formed during the peak period. Furthermore, by synchronizing the start of the peak fall period with the start of the change from the peak value in the forward feed to the peak value in the reverse feed, a strong upward force can be applied to the droplet, thereby reliably detaching the droplet and transferring it to the molten pool.

[0044] More preferably, in this embodiment, the change period from the peak value in the forward feed to the peak value in the reverse feed is equal to or shorter than the peak fall period, which further strengthens the upward force acting on the droplet, thereby more reliably separating the droplet and transferring it to the molten pool.

[0045] More preferably, in this embodiment, the arc length is controlled by modulating at least the peak current. In this way, the pulse period is set to a predetermined value, and the average feed rate can be set to a predetermined value. As a result, fluctuations in the average feed rate, which result in fluctuations in the bead appearance and penetration shape, can be suppressed. [Explanation of symbols]

[0046] 1 welding wire 2 Base material 3. Arc 4 welding torches 5 Feeding roll DV drive circuit Dv drive signal EF Feed speed error amplifier circuit Ef Feed speed error amplification signal EI current error amplifier circuit Ei Current error amplification signal EV voltage error amplifier circuit Ev Voltage error amplified signal FAD average feed speed detection circuit Fad Average feed speed detection signal FAR Average feed speed setting circuit Far Average feed speed setting signal FC feed control circuit Fc feed control signal FR feed speed setting circuit Fr feed speed setting signal Fw Feeding speed Ib Base current Ibr Base current setting signal IC current modulation circuit ID welding current detection circuit Id Welding current detection signal Ik Peak falling current Ip Peak current Ipr Peak current setting signal IR welding current setting circuit Ir Welding current setting signal Iu Peak rising current Iw Welding current MC Power Control Circuit On Start Signal PS Welding Power Supply RC Robot Control Device Tb Base Period TBR Base Period Setting Circuit Tbr Base Period Setting Signal Tfk Falling Change Period TFKR Falling Change Period Setting Circuit Tfkr Falling Change Period Setting Signal Tfu Rising Change Period TFUR Rising Change Period Setting Circuit Tfur Rising Change Period Setting Signal Tk Peak Falling Period TKR Peak Falling Period Setting Circuit Tkr Peak Falling Period Setting Signal Tp Peak Period TPR Peak Period Setting Circuit Tpr Peak Period Setting Signal Tu Peak Rising Period TUR Peak Rising Period Setting Circuit Tur Peak Rising Period Setting Signal VAV Welding Voltage Averaging Circuit Vav Welding Voltage Average Value Signal Vb Base Voltage VD Welding Voltage Detection Circuit Vd Welding Voltage Detection Signal Vp Peak Voltage VR Welding Voltage Setting Circuit Vr Welding Voltage Setting Signal Vw Welding Voltage WL Reactor WM Feed Motor Wr Reverse Feed Peak Value WRR Reverse Feed Peak Value Setting Circuit Wrr Reverse Feed Peak Value Setting Signal Ws Forward Feed Peak Value WSR Forward Feed Peak Value Setting Circuit Wsr Forward Feed Peak Value Setting Signal

Claims

1. feeding a welding wire, during the peak rising period, energizing a peak rising current that rises from the value of the base current to the value of the peak current, during the peak period, energizing the peak current, during the peak falling period, energizing a peak falling current that falls from the value of the peak current to the value of the base current, and during the base period, energizing the base current, and repeating these energizations as one pulse cycle to perform welding. In the pulse arc welding control method, the welding wire repeats forward feeding and reverse feeding, and performs reverse feeding at least during the base period, changing the forward feeding peak value and the reverse feeding peak value based on the average value of the welding voltage, A pulse arc welding control method characterized by this.

2. changing the forward feeding peak value and the reverse feeding peak value based on the error between the average value of the welding voltage and the set value of the welding voltage, The pulse arc welding control method according to claim 1, characterized by this.

3. changing the forward feeding peak value and the reverse feeding peak value so that the average value of the feeding speed of the welding wire becomes a predetermined value, The pulse arc welding control method according to claim 1 or 2, characterized by this.

4. The feeding speed of the welding wire is starting to change from the reverse feeding peak value to the forward feeding peak value at the start of the peak rising period, starting to change from the forward feeding peak value to the reverse feeding peak value at the start of the peak falling period, The pulse arc welding control method according to claim 1 or 2, characterized by this.

5. The change period from the forward feeding peak value to the reverse feeding peak value is equal to or less than the peak falling period, The pulse arc welding control method according to claim 4, characterized by this.

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