JP3190736B2 - Consumable electrode arc welding method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a consumable electrode type arc which performs welding along a welding line while weaving a welding torch right and left in a V-shaped, L-shaped or similar shape groove. The present invention relates to a welding method, and more particularly to an arc welding method using welding line automatic copying control for correctly copying a welding torch to a welding line.

[0002]

2. Description of the Related Art In automatic profiling control of a welding line, for example, a welding torch 1 is shown in a V-shaped groove as shown in FIG. 13 with the left and right (L at the left end, R at the right end, and O at the weaving center). ) Is generally used to utilize the relationship between the wire protrusion length and the welding current when weaving is performed. As this type of method, for example, Japanese Unexamined Patent Publication No.
There is a technique disclosed in, for example, Japanese Patent Application Laid-Open No. 1-144272.

In this prior art, as shown in FIGS. 14 (a) and 14 (b), the welding current waveform when the weaving center coincides with the welding line is shown in FIGS. 15 (a), (b) and FIG. 16
As shown in (a) and (b), the fact that the welding current waveform is different when the weaving center does not coincide with the welding line is used.

In other words, in the weaving left-right scanning, the difference ΔIL = IL ₁ −IL ₂ between the maximum current value IL ₁ and the minimum current value IL ₂ during the process from the L end to the R end, and
Difference ΔIR = IR ₁ -IR ₂ between the maximum current value IR ₁ and the minimum current value IR ₂ in stroke from R end to L end, FIG. 14
In the states shown in FIGS. 15A and 15B, ΔIL = ΔIR, and FIG.
In the states shown in FIGS. 16A and 16B, ΔIL> ΔIR, and FIG.
It is used that ΔIL <ΔIR in the states shown in (a) and (b).

Accordingly, if ΔIL> ΔIR, FIG.
(a) and (b), the position of the welding torch 1 is corrected rightward by a predetermined amount K, and if ΔIL <ΔIR, FIG. ,
As shown in (b), the welding torch 1
Is corrected to the left by the fixed amount K. Such a correcting operation is performed every half cycle of the weaving, and the center of the weaving of the welding torch 1 is automatically made to follow the welding line.

[0006]

However, in the conventional consumable electrode type arc welding method, since the correction amount of one welding torch position is fixed at a fixed amount K, there is a limit in the follow-up range, and the target welding range is limited. If the line changes suddenly or if the welding line deviates greatly from the center of the weaving, it cannot follow quickly. Further, if the value of the correction amount K for one time is extremely increased in order to widen the following range, there is a problem that a meandering bead is generated.

SUMMARY OF THE INVENTION The present invention is intended to solve such a problem, and consumable electrode type arc welding in which the amount of correction of the welding torch position is variable to improve the followability of a welding line without generating a meandering bead. The aim is to provide a method.

[0008]

To achieve the above object, a consumable electrode type arc welding method according to the present invention is provided.
Based on the welding current detected while periodically weaving the welding torch, the welding torch corrects the position with respect to the welding line and performs welding while following the welding line, and based on the welding current, Welding torch
The current correction direction for the welding line is a right direction and a left direction.
A non-direction 0 is determined, and a correction amount corresponding to the current correction direction is added to or subtracted from a previous correction amount of the welding torch for the welding line, and the current correction amount for the welding line of the welding torch is calculated. The position of the welding torch is moved in the current correction direction by the current correction amount.

[0009] The invention according to claim 2 provides a welding torch with a peripheral.
Based on the welding current detected during periodic weaving.
And correct the position of the welding torch with respect to the welding line.
Consumable electrode type arc welding that performs welding while following the welding line
The method comprises the steps of:
This time the correction direction for the welding line is right and left
Or non-directional 0, and (i) the welding
When the previous correction amount with respect to the weld line of over switch is a is and the current correction direction is not non-oriented 0 0 or, the front
When the correction amount is not 0 and the correction direction this time is no direction 0
If the previous correction direction of the welding torch with respect to the welding line is the same as the current correction direction, a value obtained by adding a predetermined fixed correction amount to the previous correction amount in the current correction direction is used. (Ii) the previous correction amount is not 0 and the current correction direction is no direction 0
If it is, the constant correction amount and the current correction amount those added to the previous correction amount to the previous correction direction opposite to the direction, (iii) the a previous correction amount is 0 and the current correction direction Is zero in the non-direction , the previous correction amount is used as the current correction amount as it is, and (iv) the previous correction amount is
If the current correction direction is not 0 and the current correction direction is not the non-direction 0, and the previous correction direction and the current correction direction are reversed, a value twice the fixed correction amount is set in the current correction direction. The amount added to the previous correction amount shall be the current correction amount.
It is characterized by.

[0010] Further, the invention according to claim 3 provides a welding torch.
Based on the welding current detected while weaving periodically,
And correct the position of the welding torch with respect to the welding line.
Consumable electrode type arc welding that performs welding while following the welding line
The welding method based on the welding current.
The direction of correction this time with respect to the welding line
Direction or non-direction 0, and (i) the welding
When the previous correction amount with respect to the weld line of the torch at it and said time correction direction is not non-oriented 0 0 or, the
The previous correction amount is not 0 and the current correction direction is no direction 0
If the previous correction direction of the welding torch with respect to the welding line and the current correction direction are the same, a preset fixed correction amount is added to the previous correction amount in the current correction direction. (Ii) when the current correction direction is no direction 0, the previous correction amount is directly used as the current correction amount; and (iii) the previous correction amount.
If the amount is not 0 and the current correction direction is not the non-direction 0, and the previous correction direction and the current correction direction are reversed, a value twice the fixed correction amount is used. The value added to the previous correction amount in the current correction direction is the current correction amount.
It is characterized by:

[0011]

According to the consumable electrode type arc welding method of the present invention described above, the current correction amount of the welding torch with respect to the welding line is variable in accordance with the current correction direction of the welding torch with the welding line. When the position correction direction constantly changes, the amount of one correction can be reduced. On the other hand, when the center of the weaving and the welding line are largely displaced, the amount of one correction can be increased.

[0012]

1 to 5 show a consumable electrode type arc welding method as a first embodiment of the present invention, and FIG. FIG. 2 is a flowchart for explaining the procedure for correcting the position of the welding torch, FIG. 3 is a block diagram showing an arc welding apparatus to which the method of this embodiment is applied, and FIGS. 5 is a graph showing the weld line following ability when the method of the present embodiment is applied.

First, an arc welding apparatus to which the method of this embodiment is applied will be described with reference to FIG. 3. In FIG. 3, reference numeral 1 denotes a welding torch, 2 denotes a work having a V-shaped groove 2a, and 3 denotes a tip of an arm. A multi-joint type arc welding robot which mounts a welding torch 1 on a part thereof and performs welding on the work 2 while controlling the position of the welding torch 1, and a robot control panel 4 for controlling the operation of the arc welding robot 3. It is.

The robot control panel 4 has a V-shaped groove 2a.
For performing a weaving operation of the welding torch 1 to the left and right within the robot, driving and controlling each arm of the arc welding robot 3 based on the calculation result, and oscillatingly driving the welding torch 1 at a predetermined weaving frequency. It is.

Reference numeral 5 denotes a welding power source for supplying electric power for arc welding, and reference numeral 6 denotes a shunt attached to the welding power source 5 from which a welding current is detected. The welding current detected from the shunt 6 is digitally converted by an A / D converter in the robot control panel 4, and based on the welding current digital value and an end signal indicating the weaving end used for the weaving operation, the robot control panel is used. 4, the position correction direction and the amount of one correction of the welding torch 1 are calculated in accordance with the flowcharts described later with reference to FIGS.
Output to Accordingly, the position of the welding torch 1 with respect to the welding line is corrected based on the welding current detected while periodically weaving the welding torch 1, and welding is performed while following the welding line.

The apparatus configured as shown in FIG.
In the first embodiment of the present invention, according to the flowcharts shown in FIGS. 1 and 2, the welding line automatic copying control for correctly copying the welding torch 1 to the welding line is performed as follows.

First, with reference to FIG. 2, a description will be given of a basic procedure for correcting the position of the welding torch common to the second embodiment and the third embodiment which will be described later. determines whether or not (step S1), and when it is in said transition section, while sampling the maximum current value IL ₁ and the minimum current value IL ₂ in the transition section (step S2), and the migration If that is the welding torch 1 is not in interval when in transition section of the L ends the R edge samples the maximum current value IR ₁ and the minimum current value IR ₂ in the transition section (step S3).

When it is determined that the half cycle of the weaving cycle is completed and not the first half cycle (steps S4 and S4).
5), and difference ΔIL = IL ₁ -IL _2, the maximum current value IL ₁ and the minimum current value IL ₂ in stroke to R terminal from L end,
Difference between the maximum current value IR ₁ and the minimum current value IR ₂ in stroke from R end to L ends .DELTA.iR = calculates the IR ₁ -IR ₂ (step S6). Unless the stroke for at least one cycle is completed, the four current values IL ₁ , IL ₂ , IR ₁ , and IR ₂ required for the arithmetic processing from step S 6 cannot be obtained. Is being done.

After calculating these differences ΔIL and ΔIR,
A current correction direction and a current correction amount are determined by a correction amount determination process described later with reference to FIG. 1 (step S7), and a control command based on the current correction direction and the current correction amount is output to the arc welding robot 3. (Step S
8) The welding torch 1 is moved in the current correction direction by the current correction amount, and the weaving center of the welding torch 1 is automatically made to follow the welding line.

Next, referring to FIG.
A description will be given of the procedure of the correction amount determination process of the first embodiment, which is performed in step S6.
L is compared with ΔIR (step A1), and it is determined whether the magnitude relation is ΔIL> ΔIR, ΔIL = ΔIR, or ΔIL <ΔIR.

If ΔIL> ΔIR, the change amount (correction direction index) u of the current correction amount coefficient α is set to +1 (step A2), and if ΔIL = ΔIR, the current correction amount coefficient α is changed. The quantity u is set to 0 (step A3), and ΔIL <Δ
In the case of IR, the change amount u of the correction amount coefficient α this time is-
1 (step A4), and the thus determined change amount u
_Is added to the previous correction amount coefficient α _OLD to calculate the current correction amount coefficient α (step A5). In this embodiment, the correction direction toward the R end is positive (+), and the correction direction toward the L end is negative (−).

Then, in order to set the upper limit of the absolute value | α | of the correction amount coefficient α to 3, it is determined whether the absolute value | α | is greater than 3 (step A6), and | α | ≦ If it is 3, α
While K (mm) is used as the correction amount U this time (step A7), α>
If it is 3, α is replaced with 3, and if α <−3, α is replaced with −.
3 and 3K (mm) or -3K (mm) is set as the current correction amount U (step A8). Here, K is a predetermined constant amount, and the correction amount at the time of the correction operation performed once this time is at most three times the constant amount K in any of the positive and negative directions by the processing of steps A6 to A8. Will be limited.

FIG. 12 shows an example of a specific correction amount determination result according to the correction amount determination processing procedure of the first embodiment described above with reference to FIG. However, in FIG. 12, L described in the column of the last-last, previous, and current correction directions indicates that the correction direction is leftward, that is, u = −.
1 is the case, 0 is the case where u = 0, R is the case where the correction direction is rightward, that is, u = + 1, and ΔL and ΔR described in the column of the correction amount are -K and + K, respectively. Corresponding.

The correction amount determination processing of the first embodiment described above with reference to FIG. 1 is based on the case where the welding line position gradually shifts as shown by three types of straight lines in FIG. To 3
Each figure shows the weld line followability when applied to each of the cases where there is a step-like shift as indicated by the types of straight lines. The step-like lines shown in FIGS. 4 and 5 respectively indicate the weaving center position with respect to the welding line position.

As described above, according to the consumable electrode type arc welding method of the first embodiment, the current correction amount U for the welding line of the welding torch 1 is variable in accordance with the current correction direction for the welding line of the welding torch 1. Therefore, when the welding current is unstable and the position correction direction is constantly fluctuating, the amount of one correction is reduced. On the other hand, when the center of the weaving and the welding line are greatly displaced, one correction is performed. The correction amount U can be increased, and the followability of the welding line is greatly improved without generating a meandering bead. In particular, in the present embodiment, as shown in FIG. 4, it is possible to stably follow the case where the welding line gradually shifts.

Next, a description will be given of a consumable electrode type arc welding method according to a second embodiment of the present invention with reference to FIGS. 6 to 8. FIG. 6 is a flow chart for explaining the welding torch position correcting procedure, and FIGS. FIG. 8 is a graph showing the weld line following ability when the method of the present embodiment is applied.

Here, the apparatus to which the method of the second embodiment is applied is completely the same as that described with reference to FIG. 3, and a description thereof will be omitted. The basic procedure of correcting the position of the welding torch by the robot control panel 4 is completely the same as that described with reference to FIG. 2, and a description thereof will be omitted.

The second embodiment differs from the first embodiment in that step S in the flowchart of FIG.
7 is only the part of the correction amount determination processing procedure, the correction amount determination processing procedure of the second embodiment will be described below with reference to FIG. First, similarly to steps A1 to A4 of the first embodiment, the first four steps B1 to B4
The current correction direction index (the change amount of the current correction amount coefficient α in the first embodiment) u is set to any one of +1, 0, and −1 according to the correction direction. That is, u = + 1 when it needs to be corrected to the right, u = 0 when the welding line position and the weaving center position match, and u = when it needs to be corrected to the left. It is set to -1.

Thereafter, it is determined whether or not the correction amount coefficient α _OLD was 0 last time (step B5), and it is further determined whether or not the current correction direction index u is 0 (steps B6 and B8). As a result of the determination in steps B5 and B6, α _OLD = 0 and u
If = 0 (when the previous correction amount is 0 and the current correction direction is 0), the previous correction amount coefficient α _OLD is used as it is as the current correction amount coefficient α (step B7). Thus, the previous correction amount is used as it is as the current correction amount.

As a result of the determination in steps B5 and B8, α
_{If OLD} ≠ 0 and u = 0 (when the previous correction amount is not 0 and the current correction direction is 0), 1 is added to the previous correction amount coefficient α _OLD in the direction opposite to the previous correction direction (step B9),
Thus, in steps B13 to B15 described below, |
A value obtained by adding the fixed correction amount K to the previous correction amount in the direction opposite to the previous correction direction in the range of α | ≦ 3 is used as the current correction amount U.

If u ≠ 0 is determined in step B8, it is determined whether α _OLD and u have the same sign (step B1).
0), the same sign (when the previous correction direction and the current correction direction are the same), or u ≠ in step B6.
When it is determined to be 0 (when the previous correction amount is 0 and the current correction direction is not 0), 1 is added to the previous correction amount coefficient α _OLD in the current correction direction (step B11), and as a result, From B13 to B15, the value obtained by adding the fixed correction amount K to the previous correction amount in the current correction direction in the range of | α | ≦ 3 is used as the current correction amount U.

Further, in step B10, α _OLD and u
Are not the same sign, that is, are different signs
In the case where the previous correction direction and the current correction direction are reversed, 2 is added to the previous correction amount coefficient α _OLD in the current correction direction (step B12).
According to 3 to B15, the constant correction amount K within the range of | α |
The value obtained by adding the doubled value to the previous correction amount in the current correction direction is used as the current correction amount U.

Then, steps A6 to A8 of the first embodiment
By the processing exactly the same as in steps B13 to B15, the correction amount in the correction operation performed once this time is limited to a maximum of three times the constant amount K in any of the positive and negative directions.

FIG. 12 shows an example of a specific correction amount determination result by the correction amount determination processing procedure of the second embodiment described above with reference to FIG. In addition, the correction amount determination processing of the second embodiment described above with reference to FIG. 6 is performed when the welding line position gradually shifts as shown by three types of straight lines in FIG. Each figure shows the weld line following ability when applied to each of the cases where there is a step-like shift as shown by the straight line. 7 and 8
Indicate the weaving center position with respect to the welding line position.

In this manner, the same effect as that of the first embodiment can be obtained by the consumable electrode type arc welding method of the second embodiment, and the welding line gradually shifts as shown in FIG. In this embodiment, not only can the case be stably followed, but also particularly in the present embodiment, as shown in FIG. 8, even when the welding line is displaced in a step shape.

Next, a description will be given of a consumable electrode type arc welding method according to a third embodiment of the present invention with reference to FIGS. 9 to 11. FIG. 9 is a flow chart for explaining the welding torch position correcting procedure, and FIGS. FIG. 11 is a graph showing the weld line following ability when the method of the present embodiment is applied.

Also in the third embodiment, the only difference from the first embodiment is the modification amount determination processing procedure in step S7 in the flowchart of FIG. 2, as in the second embodiment. With reference to FIG. 9, a description will be given of a correction amount determination processing procedure according to the third embodiment. First, in the same manner as steps B1 to B4 of the second embodiment, in the first four steps C1 to C4, the current correction direction index u is set to one of +1, 0, and -1 according to the correction direction. .

Thereafter, it is determined whether or not the previous correction amount coefficient α _OLD was 0 (step C5), and it is further determined whether or not the current correction direction index u is 0 (steps C6 and C8). As a result of the determination in steps C5, C6, and C8, α _OLD = 0
And u = 0 or α _OLD ≠ 0 and u = 0 (regardless of the previous correction amount, the current correction direction is 0
), The previous correction amount coefficient α _OLD is directly used as the current correction amount coefficient α (step C7), whereby the previous correction amount is directly used as the current correction amount in step C13 described later.

As a result of the determination at steps C5 and C8, α
_{If OLD} ≠ 0 and u ≠ 0, it is determined whether α _OLD and u have the same sign (step C9), and if they are the same sign (when the previous correction direction and the current correction direction are the same). Alternatively, when u ≠ 0 is determined in step C6 (when the previous correction amount is 0 and the current correction direction is not 0), 1 is added to the previous correction amount coefficient α _OLD in the current correction direction (step C10). ), Thereby, the following steps C12 to C12
According to 14, the value obtained by adding the fixed correction amount K in the current correction direction to the previous correction amount in the range of | α | ≦ 3 is used as the current correction amount U.

Further, when it is determined in step C9 that α _OLD and u are not the same sign, that is, they are different signs (when the previous correction direction and the current correction direction are reversed),
2 is added to the previous correction amount coefficient α _OLD in the current correction direction (step C11).
By C14, a value obtained by adding a value twice the fixed correction amount K in the current correction direction to the previous correction amount in the range of | α | ≦ 3 is used as the current correction amount U.

FIG. 12 shows an example of a specific correction amount determination result by the correction amount determination processing procedure of the third embodiment described above with reference to FIG. Further, the correction amount determination processing of the third embodiment described above with reference to FIG. 9 is performed when the welding line position is gradually shifted as shown by three types of straight lines in FIG. Each figure shows the weld line following ability when applied to each of the cases where there is a step-like shift as shown by the straight line. FIG.
The stepped lines shown in FIG. 0 and FIG. 11 respectively indicate the weaving center position with respect to the welding line position.

In this way, the consumable electrode type arc welding method of the third embodiment also provides the same operation and effect as the second embodiment, and the welding line gradually shifts as shown in FIG. In addition to the case where the welding line can be stably followed, as shown in FIG.

In each of the above-described embodiments, the correction amount is limited to ± 3K. However, the present invention is not limited to this, and the correction amount may be limited to another value. However, no limitation is required.

[0044]

As described above in detail, according to the consumable electrode type arc welding method of the present invention (claims 1 to 3), the current correction amount for the welding line of the welding torch is changed to the current correction amount for the welding line of the welding torch. When the welding current is unstable and the position correction direction fluctuates constantly, the amount of correction is reduced once, while the weaving center and the welding line are greatly displaced. Has been configured so that the amount of correction at one time can be increased, so that no meandering bead is generated and stability is not impaired.
This has the effect of greatly improving the followability and responsiveness of the welding line.

[Brief description of the drawings]

FIG. 1 is a flowchart for explaining a correction amount determining procedure in a consumable electrode type arc welding method as a first embodiment of the present invention.

FIG. 2 is a flowchart for explaining a welding torch position correcting procedure according to the embodiment.

FIG. 3 is a block diagram showing an arc welding apparatus to which the method of the embodiment is applied.

FIG. 4 is a graph showing the weld line following ability when the method of the first embodiment is applied.

FIG. 5 is a graph showing the weld line following ability when the method of the first embodiment is applied.

FIG. 6 is a flowchart for explaining a correction amount determining procedure in the consumable electrode type arc welding method as the second embodiment of the present invention.

FIG. 7 is a graph showing the weld line following ability when the method of the second embodiment is applied.

FIG. 8 is a graph showing the weld line following ability when the method of the second embodiment is applied.

FIG. 9 is a flowchart illustrating a procedure for determining a correction amount in a consumable electrode type arc welding method as a third embodiment of the present invention.

FIG. 10 is a graph showing the weld line following ability when the method of the third embodiment is applied.

FIG. 11 is a graph showing weld line followability when the method of the third embodiment is applied.

FIG. 12 is a table showing, in comparison with the case where the methods of the first to third embodiments are applied, the current correction amounts corresponding to the second-last, previous, and current correction directions in a concrete manner; .

FIG. 13 is a schematic view showing a general V-shaped groove and a welding torch.

FIG. 14A is a schematic view showing an arrangement state of a welding torch in a V-shaped groove when a weaving center and a welding line coincide with each other, and FIG. 14B shows welding in a state shown in FIG. 6 is a graph showing a current waveform.

FIG. 15A is a schematic view showing an arrangement state of a welding torch in a V-shaped groove when a weaving center is shifted to the left side from a welding line, and FIG. 15B is a view showing a state shown in FIG. It is a graph which shows a welding current waveform.

FIG. 16A is a schematic view showing the arrangement of a welding torch in a V-shaped groove when the weaving center is shifted to the right side of the welding line, and FIG. 16B is a view showing the state shown in FIG. It is a graph which shows a welding current waveform.

[Explanation of symbols]

 Reference Signs List 1 welding torch 2 work 2a V-shaped groove 3 arc welding robot 4 robot control panel 5 welding power source 6 shunt

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-52171 (JP, A) JP-A-1-48677 (JP, A) JP-A-2-101508 (JP, A) 52592 (JP, B2) JP-B 61-17590 (JP, B2) JP-B 3-28979 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) B23K 9/127 B23K 9 / 12

Claims (3)

(57) [Claims] 1. A consumable electrode type arc welding method for correcting a position of a welding torch with respect to a welding line based on a welding current detected while periodically weaving the welding torch and performing welding while following the welding line. On the welding line of the welding torch based on the welding current
The current correction direction is the right direction, left direction, and no direction 0.
Determined which one, said correction amount according to the current correction direction those obtained by adding or subtracting the previous correction amount with respect to the weld line of the welding torch, and this correction amount with respect to the weld line of the welding torch, the Revised A consumable electrode type arc welding method, wherein the position of the welding torch is moved in the correction direction this time by an amount. 2. Weaving a welding torch periodically.
Of the welding torch based on the welding current detected while
Welding while correcting the position with respect to the welding line and following the welding line
In the consumable electrode type arc welding method, the welding torch is welded to the welding line based on the welding current.
The current correction direction is the right direction, left direction, and no direction 0.
The previous correction amount of the welding torch with respect to the welding line is 0 .
There and if the current correction direction is not non-oriented 0, or the previous correction amount is the and the current correction direction not 0
If said current correction direction as the previous modification direction with respect to the weld line of the welding torch without a non-oriented 0 are the same, a constant correction amount which is set in advance in the previous correction amount said to this correction direction The added value is the current correction amount, and the previous correction amount is not 0 and the current correction direction is indeterminate.
If it is towards 0, the constant correction amount and the current correction amount those added to the previous correction amount to the previous correction direction opposite to the direction, the a last correction amount is 0 and the the time correction direction Solid
If the direction is 0, the previous correction amount is used as the current correction amount as it is, and the previous correction amount is not 0 and the current correction direction is
If the previous correction direction and the current correction direction are opposite to each other and are not the direction 0, a value obtained by adding a value twice the fixed correction amount in the current correction direction to the previous correction amount is used in the current correction direction. anti Worn electrode arc welding method characterized in that the correction amount. 3. Weaving a welding torch periodically.
Of the welding torch based on the welding current detected while
Welding while correcting the position with respect to the welding line and following the welding line
In the consumable electrode type arc welding method, the welding torch is welded to the welding line based on the welding current.
The current correction direction is the right direction, left direction, and no direction 0.
The previous correction amount of the welding torch with respect to the welding line is 0 .
There and if the current correction direction is not non-oriented 0, or the previous correction amount is the and the current correction direction not 0
When the previous correction direction and the current correction direction with respect to the welding line of the welding torch are the same as the non-direction 0 ,
The present correction amount is obtained by adding a preset fixed correction amount to the previous correction amount in the current correction direction. When the current correction direction is non-directional 0, the previous correction amount is used as it is. This is the current correction amount, and the previous correction amount is not 0 and the current correction direction is
If the previous correction direction and the current correction direction are opposite to each other and are not the direction 0, a value obtained by adding a value twice the fixed correction amount in the current correction direction to the previous correction amount is used in the current correction direction. anti Worn electrode arc welding method characterized in that the correction amount.