JP2010167502A - Consumable electrode type arc welding equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems in the conventional spatter reducing method using a current rapid reducing means, in which arc interruption occurs in arc regeneration to cause the instability of the arc, incorrect bead, defective penetration or the like. <P>SOLUTION: A consumable electrode type arc welding equipment includes: a constriction detection means for detecting constriction in a consumable electrode wire occurring at the last period of a short circuit; and a physical quantity rapid reducing means for rapidly reducing the physical quantity of at least any of electric current, voltage and electric power to be fed to the consumable electrode wire when constriction is detected by the constriction detection mean till the prescribed physical quantity of at least any of the electric current, voltage, and electric power reaches a first prescribed value, thus the arc interruption in the arc regeneration, the instability of the arc, the incorrect bead and the defective penetration are prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a consumable electrode type arc welding apparatus that feeds consumable electrode wires and alternately generates short circuits and arcs and welds them, and detects a constriction of consumable electrode wires that occurs at the end of the short circuit. The present invention relates to a consumable electrode type arc welding apparatus that suppresses the generation of spatter by reducing a predetermined short period.

  In recent years, there has been a demand for higher quality of welding quality such as spatter generation amount, bead appearance, and penetration. In particular, reducing spatter generation improves welding quality and prevents spatter adhesion to the jig, thereby improving maintainability and realizing an improved work environment.

  As a conventional spatter reduction method, a method is known in which the constriction at the tip of a consumable electrode wire is detected at the end of a short circuit, and the short circuit current is reduced to a predetermined current, thereby reducing spatter generated when an arc is regenerated. (For example, refer to Patent Document 1 and Patent Document 2).

  The conventional method will be described with reference to FIG. FIG. 4 shows a welding current waveform and a timing chart in which the occurrence of spatter is reduced by detecting the constriction. E1 is the time when the constriction is detected, E5 is the time when the arc is regenerated from the short circuit state, and E6 is from the arc state. When a short circuit occurs, E10 indicates a time when a third predetermined period T3 has elapsed from the occurrence of E6, and Is1 indicates a predetermined current value.

  When the constriction detecting means detects the constriction of the wire tip that occurs during the short circuit at the time point E1, the physical quantity reducing means is used to sharply reduce the current to a predetermined current value Is1 (for example, 50 A). As the squeezing detection means, for example, a method of detecting that the temporal change amount dV / dt of the welding voltage reaches a predetermined value is often used.

  As a physical quantity reducing means for sharply reducing the current, a method is used in which a switching element is inserted into the DC output of the welding power source and a resistor is connected in parallel to this switching element. When the current is sharply reduced, The switching element is cut off, and the others are turned on to short-circuit the resistor.

  Then, after the arc is regenerated at E5, the current is sharply increased to shift to arc control. Thus, by keeping the current value at the arc re-occurrence point E5 low, the occurrence of spatter at the time of arc re-occurrence can be suppressed.

  In FIG. 4, the short circuit of the wire generated at E6 during the arc is detected by the short circuit detecting means, and the current is sharply reduced using the physical quantity reducing means for the third predetermined time T3. This third predetermined time T3 is a control interval of several ms called short-circuit initial control time, and by providing this, short-circuit at the initial stage of short-circuit is ensured, unexpected micro-short circuit is reduced, The transition to the base material can be ensured, the arc can be stabilized, and the occurrence of spatter can be suppressed.

JP 59-202171 A JP-A-3-281063

However, the conventional method has a problem that, as will be described later, after the constriction is detected, the short circuit current is reduced by the physical quantity reducing means, and an arc break occurs when the arc is regenerated.

  Further, when the current is sharply dropped at the time point E6 in FIG. 4 where the short circuit is determined during the arc, if the short circuit occurs and the arc is generated, the arc cannot be maintained and the arc breaks. There was a problem.

  FIG. 5 shows an example of a welding output waveform and timing chart when arc break occurs in the prior art, E1 is when necking is detected, E5 is when arc is regenerated from a short-circuit state, and E11 is arc. At the time when the break occurs, Is1 indicates a predetermined current value.

  In FIG. 5, the constriction detecting means detects the constriction at the time point E1 during the short circuit, and the current is sharply reduced to a predetermined current value Is1 (for example, 50 A) using the physical quantity reducing means.

  As a physical quantity reducing means for sharply reducing the current, if a switching element is inserted into the DC output of the welding power source and a resistor is connected in parallel to the switching element, the switching element is used to reduce the current sharply. Is turned off (off state), and otherwise the conduction (on state) is made to short-circuit the resistor.

  After the arc is regenerated at E5, the switching element is turned on (on state), the current is increased sharply, and the process shifts to arc control. At this time, since a switching element composed of an IGBT or the like has a delay in turn-on time, a power loss due to the resistance occurs immediately after the arc transition, and sufficient power is supplied between the wire and the base material to sustain the arc. May not be able to be supplied, resulting in arc breakage.

  In recent years, reactor-less welding control has become common as a background to the problem of arc breakage, and the effect of holding an arc due to the current holding function of the reactor has been weakened. In other words, it is possible to reduce the short-circuit current when the arc is regenerated to a lower value (30 A or the like) than the conventional (100 A or the like).

  When arc breakage occurs, the insufficient heat input to the base metal due to arc breakage causes arc instability, bead fraud, and poor penetration, and induces further welding instability.

  In order to avoid arc interruption, it is effective to set a predetermined current value Is1 high (for example, 100 A). However, as a result, the short-circuit current at the time of arc regeneration cannot be sufficiently reduced, and the spatter reduction performance. Cannot be fully utilized.

  In addition, a method of increasing the L value of the reactor in the welding path is effective, and this improves the current holding function and makes it difficult for arc breakage to occur. It becomes difficult to realize a simple current waveform.

  Further, when the output is suddenly reduced, a desired current drooping degree (for example, −5000 A / ms) cannot be obtained, and a desired welding control performance cannot be realized.

  Thus, it was very difficult to prevent arc breakage while keeping the short-circuit current during arc regeneration low to ensure the spatter reduction performance.

An object of the present invention is to provide an arc welding method capable of preventing arc breakage occurring at the time of re-arcing from a short circuit and arc break occurring at the time of occurrence of a micro short circuit, and preventing unstable welding, improper bead and poor penetration. And

  In order to solve the above-mentioned problems, a consumable electrode arc welding apparatus according to the present invention is a consumable electrode arc welding apparatus that feeds a consumable electrode wire and welds by alternately generating a short circuit and an arc. A short-circuit detecting means for determining an arc state; and a second predetermined physical quantity of at least one of current, voltage or power supplied to the consumable electrode wire when the short-circuit detecting means detects a short circuit from the arc. A physical quantity rapid decrease means that rapidly decreases until reaching a value and / or when a second predetermined period elapses, the physical quantity rapid decrease means until a second predetermined value is reached and / or until a second predetermined period elapses The supply physical quantity is rapidly reduced by turning off the switching element, and when the second predetermined value is reached and / or when the second predetermined period elapses. It is an conduction.

  As described above, the consumable electrode arc welding apparatus of the present invention is a consumable electrode arc welding apparatus that feeds a consumable electrode wire and welds by alternately generating a short circuit and an arc. A short-circuit detecting means for determining the at least one predetermined supply physical quantity of current, voltage or power supplied to the consumable electrode wire when the short-circuit detection means detects a short-circuit from the arc, reaches a second predetermined value. A physical quantity suddenly decreasing means that rapidly decreases until a time point and / or a time point at which a second predetermined period elapses, wherein the physical quantity suddenly decreasing means turns on the switching element until a second predetermined value is reached and / or when a second predetermined time period elapses. The supply physical quantity is suddenly reduced by making the connection non-conductive, and the switching element is made conductive when the second predetermined value is reached and / or when the second predetermined period elapses. And in, preventing arc interruption, arc unstable, bead defect, a sputter increase, can be prevented penetration of failure or the like, it is possible to suppress an adverse effect on production efficiency and working environment.

The figure which shows the welding output waveform and timing in Embodiment 1 of this invention. Block diagram of consumable electrode arc welder in Embodiment 1 of the present invention The figure which shows the welding output waveform and timing in Embodiment 1 of this invention. The figure which shows the welding output waveform and timing of the prior art The figure which shows the welding output waveform and timing at the time of the arc break of a prior art occurring

(Embodiment 1)
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing a welding output waveform and a timing chart in the present embodiment, FIG. 2 is a block diagram of a consumable electrode type arc welder in the present embodiment, and FIG. 3 is a welding in the present embodiment. It is a figure which shows an output waveform and a timing chart.

In FIGS. 1 and 3, E1 is the time when necking detection occurs, E2 is the time when a predetermined time T1 to be described later elapses from E1, and E3 has reached I1 as the switching reference of the switching element 6 to be described later E4 is the time when the output current reaches the current Is1 waiting for re-arc, which will be described later, E5 is the time when the arc is regenerated from the short circuit state, E6 is the time when the short circuit occurs from the arc state, E8 is the time when E6 is generated E7 is a time when the output current reaches I2, which is a switching reference of the switching element 6 described later, E9 is a time when the output current reaches the short-circuit initial current Is2, and E10 is a predetermined time from E6. , T1 is a first predetermined period, T2 is a second predetermined period, T3 is a third predetermined period, I1 is a first predetermined current value, and I2 is a second predetermined current. , Is1 predetermined current value, Is2 represents a predetermined current value.

  The above-mentioned I1, Is1, I2, Is2, T1, T2, and T3 are determined based on time, for example.

  In FIG. 2, 1 is a primary rectifier, 2 is a smoothing capacitor, 3 is a first switching element, 4 is a transformer, 5 is a secondary rectifier, 6 is a second switching element, 7 is a resistor, 8 is a reactor, 9 is a setting unit, 10 is a voltage detection unit, 11 is a current detection unit, 12 is an arc short-circuit determination unit, 13 is a constriction detection unit, 15 is a first drive unit, 16 is a welding output control unit, 17 Is a second drive unit, 18 is a sudden decrease signal generation unit, 20 is a base material, 21 is a torch for welding, and 22 is a wire for welding.

  The operation of the consumable electrode type arc welding apparatus configured as described above will be described.

  In FIG. 2, the commercial power input (200 V) is converted into a DC voltage by a primary rectifier 1 composed of a diode or the like and a smoothing capacitor 2 composed of an electrolytic capacitor or the like, and PWM ( The first switching element 4 is driven by an inverter of a first switching element 3 including an IGBT (Insulated Gate Bipolar Transistor), a MOSFET (Metal-Oxide Semiconductor Field Transistor), and the like driven by a pulse wide modulation (Pulse Wide Modulation) operation or a phase shift operation. Is converted into high-frequency alternating current suitable for welding, rectified by the secondary rectification unit 5 configured by a diode or the like, driven by the drive unit 17 and configured by a second switch configured by an IGBT or the like. The output is smoothed by the reactor 8 via the switching element 6 and the resistance unit 7 connected in parallel to the second switch element 6, and is supplied to the wire 22 that is a consumable electrode from the power supply chip inside the torch 21. An arc is generated between the tip and the base material 20.

  The squeezing detection unit 13, which is a squeezing detection unit, receives the voltage detection signal from the voltage detection unit 10, calculates a voltage differential value, and sets the detection level (for example, 0.5 V / ms) set by the setting unit 9. If it reaches, a constriction signal is output as a constriction is detected.

  In addition, the squeezing detection occurs at the time point E1 in FIG. 1, and the squeezing signal output from the squeezing detection unit 13 becomes a high level. Upon receiving the squeezing signal from the squeezing detection unit 13, a sudden decrease signal generation unit 18 constituted by a CPU (Central Processing Unit) or the like outputs a sudden decrease signal to the drive unit 17. The drive unit 17 operates so as to cut off (turn off) the second switching element 6 while the sudden decrease signal from the sudden decrease signal generation unit 18 is at the LOW level. As a result, the welding current is arced through the resistance unit 7. The welding output control unit 16 that is supplied with power and at the same time configured by a CPU or the like controls the inverter configured by the first switching element 3 via the first driving unit 15, and converts the welding current to a predetermined current value I1 (for example, 100A).

Then, at the time point E3 when the welding current output detected by the current detection unit 11 constituted by CT (Current Transformer) or the like reaches the first predetermined value I1 set by the setting unit 9, the sudden decrease signal generation unit 18 stops the output of the sudden decrease signal, the second drive unit 17 brings the second switching element 6 into a conducting state, and the current value is reduced to a predetermined current Is1 (for example, 50 A).

The first predetermined value I1 may be a fixed value (for example, 100A), or a function of a welding current at the time when the necking is detected by the necking detecting means (for example, set to 100A when detected at 300A). It may be a function obtained from at least one of the wire diameter of the consumable electrode wire to be fed, the wire type, the wire protrusion length, the shield gas to be supplied, and the set current region of the welding current, and the ratio of the temporal change of the welding voltage is large. (For example, if the dV / dt value at the time of detecting the constriction is 1 V / ms, it is set to 100 A), and the integrated value of the welding current of the current short circuit (for example, until the time of detecting the constriction) If the integrated welding current value is 300 A · s, it may be determined from 100 A).

Also, the point in time when the sudden decrease signal generator 18 stops outputting the sudden decrease signal and the second drive unit 17 brings the second switching element 6 into the conducting state is the point in time E1 when the constriction is detected as shown in FIG. From this time, the sudden decrease signal generator 18 may count the time until the time point E2 when the first predetermined time T1 set by the setting unit 9 elapses.
Alternatively, either the time point E3 when the welding current output shown in FIG. 1 reaches the first predetermined value I1 or the time point E2 when the first predetermined time T1 elapses from the time point E1 when the constriction is detected shown in FIG. 3 occurs. It may be a point in time.

  Or it is good also as a point in time when both the point E3 when the welding current output reached the first predetermined value I1 and the point E2 when the first predetermined time T1 elapses from the point when the constriction is detected.

  The first predetermined time T1 may be a fixed value (for example, 50 us), or a function of the welding current at the time when the constriction is detected by the constriction detecting means (for example, set to 50 us when detected at 300 A). It may be a function obtained from at least one of the wire diameter of the consumable electrode wire to be fed, the wire type, the wire protrusion length, the shield gas to be supplied, and the setting current of the welding current, and the magnitude of the rate of change of the welding voltage with time (For example, if the dV / dt value at the time of detecting the constriction is 1 V / ms, the value may be set to 50 us). If the integrated current value is 300 A · s, it may be obtained from 50 us).

  In FIG. 2, when the second switching element 6 is conducted, the welding current is arc-fed through the second switching element 6 without passing through the resistance portion 7.

In FIG. 1, arc regeneration is not performed at the time point E4 when the output current reaches Is1, and in this case, the current is controlled to the welding output Is1 until the arc is regenerated.
The arc short circuit determination unit 12 configured by a CPU or the like receives the voltage detection signal from the voltage detection unit 10 and reaches a detection level (for example, 15 V) set by the setting unit 9 during the short circuit determination. The AS (Arc Short) signal is set to arc determination (High level).

  In FIG. 1, at the time E5 when the arc is regenerated from the short-circuit state, the AS signal becomes an arc (High level) determination, and the welding output control unit 16 shifts to predetermined arc control. The arc short circuit determination unit 12 sets the AS signal as a short circuit determination (Low level) when the detection level (for example, 10 V) set by the setting unit 9 is reached during the arc determination.

  At the time point E6 when the short circuit occurs, the AS signal is determined as a short circuit, the sudden decrease signal generation unit 18 outputs a sudden decrease signal, and the drive unit 17 shuts off the second switching element 6 (OFF state). As a result, the welding current is arc-fed through the resistance unit 7, and at the same time, the welding output control unit 16 configured by a CPU or the like shifts to a predetermined short-circuit initial control, and the first driving unit 15 performs the first operation. The inverter constituted by the switching element 3 is controlled to reduce the welding current to a predetermined current value I2 (for example, 50 A).

At the point E8 when the welding current output detected by the current detection unit 11 reaches the second predetermined current value I2 set by the setting unit 9, the sudden decrease signal generation unit 18 stops outputting the rapid decrease signal. The second drive unit 17 brings the second switching element 6 into a conductive state. This is because the voltage supplied between the base material 20 and the wire 22 by the resistance portion 7 is lowered unless the second switching element 6 is in a conductive state when an arc is generated during a short circuit. This is to prevent arc breakage.

  The second predetermined current value I2 may be a fixed value (for example, 75A), and is set to 75A when the arc short-circuit determining unit 12 detects a short circuit (for example, when detected at 150A). Or a function obtained from at least one of the wire diameter of the consumable electrode wire 22 to be fed, the wire type, the wire protrusion length, the shield gas to be supplied, and the set current region of the welding current.

  Also, when the sudden decrease signal generator 18 stops outputting the sudden decrease signal and the second drive unit 17 puts the second switching element 6 into the conductive state, as shown in FIG. It may be from E6 to E7 when the sudden decrease signal generation unit 18 starts counting time and the second predetermined time T2 set by the setting unit 9 has elapsed. As shown in FIG. 2 or a point E8 at which a predetermined current value I2 of 2 is reached or a point E8 when a second predetermined time T2 elapses from a point E6 when a short circuit is detected as shown in FIG. It may be the time when both the point E8 at which the second predetermined current value I2 is reached and E7 at which the second predetermined time T2 has elapsed from the time when the constriction is detected.

  The second predetermined time T2 may be a fixed value (for example, 200 us), or a function of the welding current at the time when the arc short-circuit determining unit 12 detects a short circuit (for example, set to 200 us when detected at 150 A). Alternatively, it may be a function obtained from at least one of the wire diameter of the consumable electrode wire to be fed, the wire type, the wire protrusion length, the shield gas to be supplied, and the set current region of the welding current.

  When the second switching element 6 is conducted, the welding current is arc-fed through the second switching element 6 without passing through the resistance portion 7. During normal welding, the second switching element becomes conductive. Even after the output current reaches Is2, the current is controlled to the welding output Is2 during the third predetermined time T3. At E10 after the elapse of the third predetermined time T3, the welding control unit 16 shifts to a predetermined short circuit opening control, outputs a predetermined short circuit current, and promotes the opening of the short circuit.

  As described above, the delay of the turn-on time of the second switching element 6 is absorbed by making the timing of E2 and E3 for conducting the second switching element 6 earlier than the time point E5 when the arc is generated. At the time point E5 when the re-occurrence occurs, the second switch element 6 is completely turned on, and sufficient electric power for sustaining the arc can be supplied, thereby preventing the occurrence of an arc break during arc regeneration.

It should be noted that the first predetermined period and the first predetermined current I1, which serve as a reference for the timings of E2 and E3 for conducting the second switching element 6, are determined by experiments or the like.
Even in the case where a micro short circuit occurs during the initial stage of the short circuit, by supplying the second switching element 6 in advance, the supply of power at the time of re-arcing is not hindered and arc breakage is prevented. be able to.

By preventing arc breaks as described above, arc instability, bead defects, increased spatter, poor penetration, etc. can be minimized, and adverse effects on production efficiency and work environment can be suppressed. In the consumable electrode arc welding apparatus according to the present embodiment, an example is shown in which current is detected using CT, and the first switching element 6 is switched between conduction and non-conduction when the current reaches a predetermined current. The voltage detection means may be used to detect the voltage, and when the voltage reaches a predetermined voltage, the first switching element 6 may be switched between conduction and non-conduction, or the power measurement means may be used to detect the power. The first switching element 6 may be switched between conduction and non-conduction when the predetermined power is reached.

  The consumable electrode type arc welding method of the present invention can prevent the occurrence of arc breakage and minimize the occurrence of arc instability, bead defects, increased spatter, poor penetration, etc., and adversely affects production efficiency and work environment. This is useful for arc welding techniques using spatter reduction techniques using a current steepening circuit composed of switching elements and resistors, and is used for automobiles, shipbuilding, It can be widely used in industries where spatter generation such as bridges is a problem.

E1 Neck detection point E2 E1 point T1 has elapsed E3 Output current has reached I1 E4 Output current has reached Is1 E5 Arc has been regenerated from a short-circuit point E6 Short-circuit point has occurred E7 Point E2 at which T2 has elapsed since generation of E6 Point E8 at which output current has reached I2 Point E10 at which output current has reached Is2 Point E10 at which T3 has elapsed since generation of E6 Point 11 at which arc break has occurred T1 First predetermined period T2 Second predetermined period T3 Third predetermined period I1 First predetermined value I2 Second predetermined value Is1 Predetermined current value Is2 Predetermined current value 1 Primary rectifier 2 Smoothing capacitor 3 First switching element 4 Transformer 5 Secondary rectification unit 6 Second switching element 7 Resistance unit 8 Reactor 9 Setting unit 10 Voltage detection unit 11 Current detection unit 12 Arc short-circuit determination unit 13 Constriction detection unit 15 First Turning part 16 welding output control unit 17 the second driving unit 18 rapidly decreases signal generator 20 preforms 21 Torch 22 Wire

Claims (6)

A consumable electrode type arc welding apparatus that feeds consumable electrode wires and welds by alternately generating short circuits and arcs, and short-circuit detecting means for distinguishing between short-circuit and arc states, and short-circuiting from the arc by the short-circuit detecting means A physical quantity reducing means for reducing at least one predetermined supply physical quantity of current, voltage or power supplied to the consumable electrode wire when the consumable electrode wire is detected, and the physical quantity reducing means is inserted in series with the welding output. 2 and a resistor connected in parallel to the second switching element, and the physical quantity reducing means keeps the second switching element nonconductive until reaching a second predetermined value. When the physical quantity is reduced and the second predetermined value is reached, the second switching element is turned on, and the welding output control unit is configured by the first switching element. Consumable electrode type arc welding device to control the inverter to reduce the supply physical quantity to said fourth predetermined value lower than the second predetermined value being. A consumable electrode type arc welding apparatus that feeds consumable electrode wires and welds by alternately generating short circuits and arcs, and short-circuit detecting means for distinguishing between short-circuit and arc states, and short-circuiting from the arc by the short-circuit detecting means A physical quantity reducing means for reducing at least one predetermined supply physical quantity of current, voltage or power supplied to the consumable electrode wire when the consumable electrode wire is detected, and the physical quantity reducing means is inserted in series with the welding output. 2 and a resistor connected in parallel to the second switching element, and the physical quantity reducing means keeps the second switching element non-conductive until a second predetermined period elapses. The physical quantity is reduced, and when the second predetermined period elapses, the second switching element is turned on, and the welding output control unit has the first switching element. Consumable electrode type arc welding device to reduce the supply physical quantity lower predetermined amount than the supply physical quantity at the time of controlling the inverter composed elapsed the second predetermined period. A consumable electrode type arc welding apparatus that feeds consumable electrode wires and welds by alternately generating short circuits and arcs, and short-circuit detecting means for distinguishing between short-circuit and arc states, and short-circuiting from the arc by the short-circuit detecting means A physical quantity reducing means for reducing at least one predetermined supply physical quantity of current, voltage or power supplied to the consumable electrode wire when the consumable electrode wire is detected, and the physical quantity reducing means is inserted in series with the welding output. 2 switching elements and a resistor connected in parallel to the 2 switching elements, and the physical quantity reducing means until the second predetermined value is reached or until the second predetermined period elapses, whichever comes first The supply physical quantity is reduced by disabling the second switching element until the point of time, and the second switching element is reduced at the earlier point of time. Consumable electrode arc welding in which the element is made conductive and the welding output control unit controls the inverter constituted by the first switching element to reduce the supply physical quantity to a predetermined quantity lower than the supply physical quantity at the earlier time point. apparatus. A consumable electrode type arc welding apparatus that feeds consumable electrode wires and welds by alternately generating short circuits and arcs, and short-circuit detecting means for distinguishing between short-circuit and arc states, and short-circuiting from the arc by the short-circuit detecting means A physical quantity reducing means for reducing at least one predetermined supply physical quantity of current, voltage or power supplied to the consumable electrode wire when the consumable electrode wire is detected, and the physical quantity reducing means is inserted in series with the welding output. 2 switching elements and a resistor connected in parallel to the 2 switching elements, and the physical quantity reducing means is later until a second predetermined value is reached or until a second predetermined period elapses. The supply physical quantity is reduced by disabling the second switching element until the point of time, and the second switching element is reduced at the later point of time. Consumable electrode arc welding in which the element is made conductive and the welding output control unit controls the inverter constituted by the first switching element to reduce the supply physical quantity to a predetermined quantity lower than the supply physical quantity at the later time point. apparatus. The second predetermined value is based on either the welding current or the welding voltage when a short circuit is detected from the arc by the short circuit detecting means, or the wire diameter, wire type, wire protrusion length of the consumable electrode wire to be fed, The consumable electrode type arc welding apparatus according to claim 1, wherein the consumable electrode type arc welding apparatus is determined based on at least one of shielding gas to be supplied. The second predetermined period is based on either the welding current or the welding voltage when a short circuit is detected from the arc by the short circuit detection means, or the wire diameter, wire type, wire protrusion length of the consumable electrode wire to be fed, 5. The consumable electrode type arc welding apparatus according to claim 2, wherein the consumable electrode type arc welding apparatus is determined based on at least one of shielding gas to be supplied.

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