JP2002307171A - Multi-point welding gun device and method for multi- point welding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve workability and a productivity by enabling weld of members of different materials by using a single welding gun device, and almost simultaneous weld of a plurality of welding spots, thereby dispensing with such an entangled work as replacement of the welding gun device. SOLUTION: The device is provided with a first welding gun part 16 which functions as a primary electric current supply, an electrode connection part 24 with which the first welding gun part 16 is connected when an electric current is supplied from the first welding gun part 16, a cable part 26 which connects the electrode connection part 24, an upper side arm 32 and a lower side arm 34, and a second welding gun part 20 furnished with a plurality of arms and electrode tips 12a and 12b which energize thin works 18a and 18b as a secondary electric current supply, and the length and the resistance of the cable part 26, and the pressurizing force of the electrode tips 12a and 12b are adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-point welding gun device and a multi-point welding method capable of spot-welding overlapping portions of thin-walled members such as a door panel, a bonnet and a trunk of an automobile.

[0002]

2. Description of the Related Art Conventionally, in a mixed production line of an automobile, various welding gun devices have been used to weld a body or the like using a normal steel plate or a body or the like using an aluminum steel plate.

[0003] These welding guns are constructed so that only one welding site can be welded for one energization.

[0004]

At present, in an automobile assembly plant, a mixed production of assembling a plurality of types of vehicles on the same assembly line is performed. Aluminum sheets are used for reasons such as weight reduction.

[0005] However, in the welding gun device according to the prior art, when welding a body or the like using a normal steel plate and when welding a body or the like using an aluminum steel plate, for example, an electric current is applied during welding. Since the amount of current, pressing force, etc. are different, it is necessary to set a dedicated welding gun device for each material and select and use a welding gun device for each material when performing welding. Is done.

[0006] Further, an installation space for a plurality of welding gun devices is required, and there is a concern that the periphery of the work space becomes narrow.

Further, in the welding gun according to the prior art, since only one welding can be performed for one energization of the electrode tip, a portion having a plurality of welding locations such as a door panel is welded. In doing so, it takes a long time to work, and there is a possibility that subtle distortion, twisting, etc. of the member may occur due to welding at a plurality of welding points of the same member one by one. There is the complexity of having to weld.

In resistance welding conventionally employed in spot welding, when a plurality of welding points are to be welded simultaneously, current tends to flow to a portion having a low resistance value in a member to be welded, and a high resistance value is obtained. There is a feature that current does not easily flow there. As a result, there is a possibility that welding is insufficient at a portion having a high resistance value, and that welding strength is insufficient.

The present invention has been made in consideration of the above various concerns and the like. A single welding gun device can be used to weld members of different materials, and a plurality of welding locations can be substantially removed. It is an object of the present invention to provide a multi-point welding gun device and a multi-point welding method that can simultaneously perform welding.

[0010]

In order to achieve the above object, the present invention provides a first welding gun portion used as a current supply source for spot welding, and a current from the first welding gun portion. And a second welding gun portion having a plurality of sets of electrode tips branched from the electrode connecting portion and used for spot welding, the electrode connecting portion and the second welding gun portion. And a conductor portion that is electrically connected to the plurality of welding portions of the work and distributes the current supplied to the first welding gun portion to the plurality of electrodes of the second welding gun portion substantially equally. Wherein a plurality of welding portions of the work are welded substantially simultaneously by the second welding gun portion.

The present invention also relates to a multi-point welding method for spot welding a plurality of welding portions of a work, wherein a first welding gun used for spot welding is used as a primary current supply source, A second welding gun portion having a plurality of sets of electrode tips branched from a current supply source is used as a secondary current supply source, and a current supplied to the primary current supply source is supplied to each of a plurality of welding portions of a workpiece. The method is characterized in that the plurality of welding portions of the work are substantially simultaneously distributed to the secondary-side current supply sources substantially simultaneously.

By adjusting the length of the conductor, the resistance of the conductor and the pressure of the electrode,
It is preferable to distribute the current value substantially uniformly to the electrode tip of the second welding gun portion.

Further, the first welding gun portion is formed by a spot welding gun for welding an aluminum steel plate,
The welding gun portion may include a plurality of other spot welding guns for welding ordinary steel plates, and the first welding gun portion may be provided detachably from the electrode connection portion.

Further, the work may be at least any one of a body, a door panel, a bonnet, a trunk and the like of an automobile.

Further, it is preferable that the second welding gun is fixed on the support table by a connecting member connecting the upper arm of the second welding gun with the first fixing member and the second fixing member.

[0016] Further, the conductor portion is composed of a plurality of cables formed of a flexible material so as to be flexible, and one end of the cable is connected to a plate member sandwiching a first insulating member. Is connected to a first connecting member connected to one of the arms and a second connecting member connected to the other of the arms via the second insulating member.

Further, it is preferable that the second welding gun portion electrically connected via the cable is constituted by up to four spot welding guns.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a multi-point welding method according to the present invention will be described below in detail with reference to the accompanying drawings. .

In FIG. 1, reference numeral 10 indicates a multipoint welding gun device according to an embodiment of the present invention. In the embodiment of the present invention, a pair of electrode tips 12a, 1
A multi-point welding gun device in which four sets of 2b are connected and capable of welding four welding points substantially simultaneously will be described.

The multi-point welding gun device 10 includes a support base 14 to which the multi-point welding gun device 10 is fixed, and a first welding gun portion 16 (see FIGS. 3 and 4) functioning as a primary-side current supply source. ) And a pair of thin-walled works 18a, 18b
(See FIGS. 3 and 4). A second welding gun portion 20 provided with a plurality of pairs of arms for supplying current to an electrode tip 22 of the first welding gun portion 16 when current is supplied (see FIGS. 3 and 4).
Electrode connection part 24 to which the electrode connection part 24 is connected.
And a cable section (conductor section) 26 for electrically connecting the second welding gun section 20 with the second welding gun section 20.

The first welding gun portion 16 is a single high-current spot welding gun (for example, a welding gun for aluminum plate), and the second welding gun portion 20 is a plurality of small-current spot welding guns. Welding gun (for example, welding gun for ordinary steel plate)
Are used, and the first welding gun portion 16 and the second welding gun portion 20 can be used independently.

As shown in FIGS. 3 and 4, the support base 14 is formed in an L-shaped cross section,
A support 28 to which the welding gun 20 is fixed is formed, and a support member 30 to which the electrode connecting part 24 is fixed on the upper surface is connected to the other end via a bolt. As a current supply source connected to the electrode connection part 24 at the time of current supply, for example, a first welding gun part 16 for spot welding a pair of aluminum steel plates is used.

The second welding gun portion 20 is formed to have a substantially U-shaped cross section, and has an upper arm 32 connected to the upper side, a lower arm 34 connected to the lower side, and an upper arm 32.
And a pair of substantially cylindrical electrode tips 12a and 12b connected to each other so as to be opposed to the tip of the lower arm 34 and the tip of the lower arm 34, respectively.

The upper arm 32 has a substantially L-shaped cross section, and has an electrode tip 12a at one end.
The other end is connected to a first upper terminal 36 described later via a bolt 35 on the upper surface and one end of a first connecting member 38 formed in a substantially L-shaped cross section and connected to the lower surface. Between the two.

The lower arm 34 is formed to have a substantially L-shaped cross section, and has an electrode tip 12b at one end.
The first connecting member (connecting member) 40 formed of a plate-like material is integrally connected to both sides of the other end. A plurality of through holes are formed on both lower sides of the first connecting member 40.

One of the through holes is fixed to both side surfaces of a first fixing member 42 described later via a screw member, and the other is fixed to the second fixing member 46 via a screw member. The first fixing member 42 is fixed via a bolt 44 to a screw hole formed on the upper surface of the column 28. The other end of the second fixing member 46 is connected to the other end of the first connecting member 38 via a second connecting member 48 having a substantially L-shaped cross section.

As shown in FIG. 6, between the second connecting member 48 and the other end of the first connecting member 38, a first insulating plate (first insulating plate) made of an insulating material is formed. Member) 50 and the third connecting member 52 are sandwiched via a bolt member 54, and a through hole 56 is provided substantially at the center of the first connecting member 38.
Are formed.

The diameter of the through hole 56 is
And an insulating collar member 58 formed into a substantially cylindrical shape is inserted between the through-hole 56 and the threaded portion of the bolt member 54. Note that an insulating washer 60 made of an insulating material is sandwiched between the bolt member 54 and the first connecting member 38 so that the current supplied to the first connecting member 38 is applied to the bolt member 54. Has been blocked.

The first connecting member 38 and the second fixing member 4
6, as shown in FIG. 6, through a through hole formed in the first connecting member 38 and the second fixing member 46, an insulating spacer 62 having a substantially circular cross section made of an insulating material is provided.
Is pinched.

That is, under the insulating action of the first insulating plate 50 and the insulating spacer 62, the current from the first upper terminal 36 and the current from the first lower terminal 78 are prevented from conducting.

As shown in FIGS. 3 and 4, the upper arm 32 is connected to both side surfaces and is fixed to a second connecting member (connecting member) 64 formed of a plate-like material via a screw member. , And a second arm connected to the upper arm 32.
A spring member (not shown) is provided between the connecting member 64 and the first connecting member 40 connected to the lower arm 34, and biases the upper arm 32 and the lower arm 34 in a direction of separating them. The first connecting member 40 and the second connecting member 64 are engaged with each other so as to be displaceable in the axial direction.

That is, the electrode tip 12a connected to the upper arm 32 and the electrode tip 12b connected to the lower arm 34 are configured to be always relatively separated from each other.

As shown in FIG. 5, the electrode connecting portion 24 is formed of a metal material (for example, copper), and is provided on a first plate (plate member) 66 provided on the upper surface side and on a lower surface side. A second plate (plate member) 68 to be provided;
Sandwiched between the first plate 66 and the second plate 68,
And a second insulating plate (second insulating member) 70 formed of an insulating material. The first welding gun portion 16 is positioned between the upper surface of the first plate 66 and the lower surface of the second plate 68.
The electrode tip 22 is pressed to supply power to the electrode connection portion 24 from the electrode tip 22.

The first plate 66 and the second plate 6
8 and the second insulating plate 70 are formed with through holes 56 at both ends thereof.
Is fixed via a bolt member 54 to a screw hole formed on the upper surface of the support member 30. The diameter of the through hole 56 is formed larger than the diameter of the threaded portion of the bolt member 54, and an insulating collar member 58 is inserted between the through hole 56 and the threaded portion of the bolt member 54.

That is, the insulating collar member 58 prevents the current flowing through the first plate 66 and the second plate 68 from flowing through the bolt member 54.

It should be noted that the distance between the second plate 68 and the support member 30 and between the upper surface of the first plate 66 and the bolt member 5
4, an insulating washer 60 is sandwiched between the first and second washers.
The current flowing through the plate 66 and the second plate 68 is prevented from flowing through the bolt member 54 and the support member 30.

The cable portion 26 is formed of a flexible material, and as shown in FIG.
Upper cable 72 coupled between upper surfaces of plate 66
a to 72d, and lower cables 74a to 74d connected between the lower arm 34 and the lower surface of the second plate 68. Each cable 72a-72d, 74a-7
The length 4d is formed to be approximately equal to each of the four sets of second welding gun portions 20 from the electrode connection portion 24.

For example, in the upper cables 72a to 72d, since the distance from the electrode connecting portion 24 to the first upper terminal 36 of the upper arm 32 to which each is electrically connected is not equal, as shown in FIG. In the XY plane, the electrode connection portion 24 and the first upper terminal 36 are connected substantially linearly, and the resulting cables 72a to 72d,
As shown in FIGS. 3 and 4, the difference between the lengths of the upper cables 74a to 74d is determined by separating the upper cables 72b and 72c connected to the center in the XZ plane from the center by a predetermined distance from the center. 72a, 72d, each cable 72a
The length of the upper cables 72a to 72d is made substantially equal by adjusting the lengths of the upper cables 72a and 74a to 74d.

That is, each of the cables 72a to 72d, 7
By making the lengths 4a to 74d substantially equal, the resistance values of the cables 72a to 72d and 74a to 74d themselves become substantially equal. Electrode tips 12a, 12 connected to
When power is supplied to b, the current is distributed approximately equally and supplied to the upper arm 32 and the lower arm 34 as substantially equal current values, so that multiple points can be welded almost simultaneously and equally.

Further, since the lengths of the upper cables 72a to 72d and the lower cables 74a to 74d are made substantially equal and then changed, the resistance value of the cable portion 26 can be changed. The current value from the first welding gun unit 16 to the second welding gun unit 20 can be controlled.

As shown in FIGS. 3 and 4, one end of each of the upper cables 72a to 72d is formed of a conductive metal material and is connected to one end of the upper arm 32 via a bolt 35. The first upper terminal 36 to be connected and the other end of the upper cables 72a to 72d are formed of a conductive metal material, and are connected to the electrode connection portion 24 via bolts 35.
Second upper terminal 7 connected to the upper surface of first plate 66 of FIG.
6 is connected to one end of each of the lower cables 74a to 74d. The first lower terminal 78 is formed of a metal material and connected to one end of the second connection member 48 via the bolt 35. The other end of each of the lower cables 74a to 74d is connected to a second lower terminal 80 formed of a metal material and connected to the lower surface of the second plate 68 of the electrode connecting portion 24 via a bolt 35. ing.

With this configuration, the current supplied from the first welding gun section 16 to the electrode connection section 24 is reduced to the first level.
Upper cables 72a-72d and lower cables 74a-74d via plate 66 and second plate 68
And the electrode tips 12a, 12b of the second welding gun 20 via the first plate 66 and the second plate 68.
Is energized.

The multi-point welding gun device 10 according to the embodiment of the present invention is basically constructed as described above. Next, the operation and effect of the device will be described.

The following describes a case where a pair of thin plate-like works (for example, a car body, a door panel, a bonnet, a trunk, etc.) 18a and 18b made of ordinary steel plates are used and the overlapped portions are spot-welded.

Here, the case where the second welding gun portion 20 is changed from the unclamped state (see FIG. 2) to the clamped state (see FIG. 3) will be described.

First, the electrode tip 12 of the lower arm 34
A pair of thin plate-shaped works 18a and 18b are brought into contact with the upper surface of b. In this case, the thin workpieces 18a and 18b are in a state of being fixed by a jig or the like (not shown). It is in a state of being isolated for a predetermined time under the action.

Next, the first welding gun 1 serving as a current supply source
6, the electrode tip 12a of the first welding gun portion 16 is brought into contact with the lower surface of the second plate 68 of the electrode connecting portion 24,
By pressing the electrode tip 12b against the upper surface of the first plate 66, the first plate 66
And the second plate 68. In this case, under the insulating action of the second insulating plate 70 sandwiched between the first plate 66 and the second plate 68, the respective currents are opposed to the first plate 66 and the second plate 6
8 is prevented from being energized.

The current supplied to the upper surface of the first plate 66 is supplied from the first plate 66 to the upper cables 72a to 72d via the second upper terminal 76, and the first upper terminal 3
6, the current supplied to the lower surface of the second plate 68 is supplied to the lower arm 74 via the second lower terminal 80.
a to 74 d are supplied to the lower arm 34 via the second upper terminal 76. In this case, the current flowing through the first connecting member 38 via the other end of the upper arm 32 by the second insulating plate 70 and the insulating spacer 62 causes the current flowing through the second fixing member 46 and the second connecting member 4
8 is prevented from being energized.

In this case, the cables 72a to 72
Since the lengths of the cables d and 74a to 74d are substantially equal, the resistance values of the cables 72a to 72d and 74a to 74d themselves are substantially equal.
The current is distributed approximately equally to the upper cables 72a to 72d and the lower cables 74a to 74d branched into books.

As a result, current is supplied to the electrode tip 12a connected to the upper arm 32 and the electrode tip 12b connected to the lower arm 34 substantially equally.

Subsequently, by pressing the upper arms 32 of the plurality of second welding gun portions 20 against the elastic force of a spring member (not shown), the electrode tip 12a is pressed against the thin plate-like work 18a. Electrode tip 12a and electrode tip 12b
The work 18a, 18b is sandwiched between the second welding gun portion 2 by sandwiching a pair of thin plate-like work 18a, 18b.
0 is in a clamped state, and a current is supplied between the electrode tip 12a and the electrode tip 12b, so that a nugget (not shown) is formed between the one work 18a and the other work 18b, and the works 18a and 18b are Strongly welded.

That is, a plurality of welding points of the works 18a and 18b are welded at substantially the same strength with substantially the same strength.

In the multipoint welding method according to the present embodiment, a case where there is no difference in resistance between a plurality of welding parts has been described. By appropriately adjusting the length of each of the cables 72a to 72d and 74a to 74d and the pressing force of the electrode according to the resistance value of each welding part, a plurality of welding points can be substantially formed regardless of the resistance difference between the welding parts. Welding can be performed almost simultaneously with the same strength.

As described above, in the present embodiment, power is supplied to the plurality of arms and the electrode tips 12a and 12b from the first welding gun portion 16 for welding an aluminum steel plate, which is a current supply source, almost uniformly via the cable portion 26. By this, the current value of the first welding gun portion 16 is substantially equally divided, so that the current value suitable for welding the aluminum steel plate (for example, about 40,000 amps,
8 cycles) is adjusted to a current value (for example, about 10,000 amps, energization time of 10 cycles) suitable for welding a normal steel plate.

That is, there is no need to separately provide a current control device or the like for controlling the current, and members of different materials such as a normal steel plate and an aluminum steel plate can be welded only by the first welding gun portion 16. A complicated operation for selecting a welding gun is not required, and workability and work efficiency can be improved. In addition, the installation space for a plurality of welding gun devices is accordingly reduced, so that the working space can be effectively utilized.

Further, the second welding gun portion 20 and the electrode connecting portion 2
The upper cables 72a to 72d and the lower cables 74a to 74d for electrically connecting the first and second cables 4 to 4 have substantially equal lengths, and the resistance values of the respective 72a to 72d and 74a to 74d are substantially equal. By adjusting the pressing force of the chips 12a and 12b, without controlling the current,
Since a plurality of welding points can be welded at substantially the same time and with the same strength, the working time can be greatly reduced, and the working efficiency can be improved.

Further, as shown in FIG.
When fixing two side beams 84, which are two reinforcing members, to the inner surface of a door panel 82 of an automobile at eight welding points 88 via four fixing brackets 86, a welding gun device 90 according to the related art includes: Since the welding points 88 of the fixing bracket 86 are sequentially welded one by one, delicate distortion, twisting, and the like are generated between the welding part and the non-welding part of the fixing bracket 86, and as a result, the fixing is performed. The side beam 84 fixed via the bracket 86 has a problem that similar delicate distortion, twist, and the like occur.
For this reason, there is the complexity that the operator has to perform the welding operation in consideration of the welding order for each condition such as a part.

On the other hand, a set of multi-point welding gun devices 10a and 10b according to this embodiment shown in FIG.
Since eight welding points 88 provided on the fixing bracket 86 can be substantially simultaneously welded, delicate distortion, twisting, and the like do not occur in the fixing bracket 86 and the side beam 84.

That is, by welding a plurality of welding points of the workpieces 18a and 18b substantially simultaneously, delicate distortion, twisting, etc. of members generated when welding a plurality of welding points of the same member one by one. Can be suppressed, and the complicated work of welding in consideration of the order of welding, which has been conventionally performed, is not required, so that the working efficiency can be improved.

[0060]

According to the present invention, the following effects can be obtained.

That is, since members of different materials can be welded only in the first welding gun portion, a complicated operation for selecting a welding gun for each member is not required, and workability and work efficiency can be improved. it can.

In addition, the installation space for a plurality of welding gun devices is reduced accordingly, so that the working space can be effectively utilized.

Further, the length of the conductor for electrically connecting the second welding gun portion and the electrode connection portion is made substantially equal, the resistance of the conductor is made substantially equal, and the pressing force of the electrode is made equal. By adjusting, the welding points can be welded at substantially the same time and with the same strength, so that the working time can be greatly reduced and the working efficiency can be improved.

Further, by welding a plurality of welding points at substantially the same time, it is possible to suppress the occurrence of delicate distortion, twisting, etc. of the members, and to perform the complicated welding in consideration of the welding order. Since no work is required,
Work efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a partially omitted perspective view of a multipoint welding gun device according to an embodiment of the present invention.

FIG. 2 is a front view of the multipoint welding gun device according to the embodiment of the present invention.

FIG. 3 is a partially omitted side view showing a state when the welding gun portion is unclamped in the multipoint welding gun device according to the embodiment of the present invention.

FIG. 4 is a partially omitted side view showing a state where the welding gun portion is clamped in the multipoint welding gun device according to the embodiment of the present invention.

FIG. 5 is a vertical sectional view taken along line VV of FIG. 2;

FIG. 6 is a partially cutaway enlarged view of a connecting portion between a first connecting member and a second connecting member of the multipoint welding gun device according to the embodiment of the present invention.

FIG. 7 is a top view when a side beam is welded to a door panel of an automobile using a welding gun device according to the related art.

FIG. 8 is a top view of the multi-point welding gun device according to the embodiment of the present invention when a side beam is welded to a door panel of an automobile.

[Explanation of symbols]

10, 10a, 10b: Multi-point welding gun device 12a, 12b: Electrode tip 14: Support base 16: First welding gun 18a, 18b: Work 20: Second welding gun 22: Electrode tip 24: Electrode connecting 26 ... Cable part 28 ... Support part 30 ... Support member 32 ... Upper arm 34 ... Lower arm 35 ... Bolt 36 ... First upper terminal 38 ... First connecting member 40 ... First connecting member 42 ... First fixing member 44 ... Bolt 46 ... Second fixing member 48 ... Second connecting member 50 ... First insulating plate 52 ... Third connecting member 54 ... Bolt member 56 ... Through hole 58 ... Insulating collar member 60 ... Insulating washer 62 ... Insulating spacer 64 ... Second Connecting member 66 First plate 68 Second plate 70 Second insulating plate 72a to 72d Upper cable 74a to 74d Lower cable 76 ... 2 upper terminal 78 first lower terminal 80 second lower terminal 82 door panel 84 side beam 86 fixing bracket 88 welding point 90 welding gun device

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B23K 11/24 358 B23K 11/24 358 // B23K 103: 10 103: 10

Claims (14)

[Claims] 1. A first welding gun portion that functions as a current supply source and is used for spot welding, an electrode connection portion to which current from the first welding gun portion is supplied, and a branch from the electrode connection portion. A second welding gun portion having a plurality of one set of electrode tips and used for spot welding, electrically connected to the electrode connection portion and the second welding gun portion, and A conductor portion for distributing a current supplied to the first welding gun portion to the plurality of electrodes of the second welding gun portion substantially evenly, wherein the plurality of welding portions of the workpiece are the second welding gun. A multi-point welding gun device characterized by being welded almost simultaneously by a part. 2. The multi-point welding gun device according to claim 1, wherein the length of said conductor portion, the resistance value of said conductor portion, and the pressure of said electrode are adjusted to adjust said second welding gun portion. A multi-point welding gun device wherein a current value is distributed substantially uniformly to an electrode tip. 3. The multi-point welding gun device according to claim 1, wherein said first welding gun portion comprises a spot welding gun for welding an aluminum steel plate, and said second welding gun portion welds an ordinary steel plate. Consisting of several other spot welding guns
The said 1st welding gun part is detachably provided with respect to the said electrode connection part, The multipoint welding gun apparatus characterized by the above-mentioned. 4. The multi-point welding gun device according to claim 1, wherein the work comprises at least one of a vehicle body, a door panel, a bonnet, a trunk and the like. 5. The multi-point welding gun device according to claim 1, wherein the second arm is connected to an upper arm of the second welding gun portion by a connecting member connecting the first fixing member and the second fixing member.
A multi-point welding gun device, wherein a welding gun portion is fixed on a support base. 6. The multi-point welding gun device according to claim 1, wherein said conductor comprises a plurality of cables formed of a flexible material so as to be flexible, and one end of said cable is a first insulating member. The other end of the cable is connected to a first connecting member connected to one of the arms and a second connecting member connected to the other of the arms via a second insulating member, respectively. A multi-point welding gun device to be connected. 7. The multi-point welding gun device according to claim 3, wherein the second welding gun portion electrically connected via the cable is constituted by up to four spot welding guns. Multi-point welding gun device characterized by the following. 8. A multi-point welding method for spot welding a plurality of welding portions of a workpiece, wherein a first welding gun used for spot welding is used as a primary current supply source, and A second welding gun portion having a plurality of branched electrode tips is used as a secondary current supply source, and a current supplied to the primary current supply source is supplied to the secondary side in accordance with a plurality of welding portions of a workpiece. A multi-point welding method, wherein the plurality of welding portions of the workpiece are substantially simultaneously distributed to current supply sources, and a plurality of welding portions are welded substantially simultaneously. 9. The multi-point welding method according to claim 8, wherein the length of the conductor portion, the resistance value of the conductor portion, and the pressing force of the electrode are adjusted respectively, so that the electrode of the second welding gun portion is adjusted. A multipoint welding method, wherein a current value is distributed to a chip substantially evenly. 10. The multi-point welding method according to claim 8, wherein the first welding gun portion is a spot welding gun for welding an aluminum steel plate, and the second welding gun portion is for welding a normal steel plate. Consisting of several other spot welding guns,
The multi-point welding method according to claim 1, wherein the first welding gun part is detachably provided to the electrode connection part. 11. The multi-point welding method according to claim 8, wherein the workpiece comprises at least one of a body, a door panel, a bonnet, a trunk, and the like of an automobile. 12. The multi-point welding method according to claim 8, wherein the second arm is connected to an upper arm of the second welding gun portion by a connecting member connecting the first fixing member and the second fixing member.
A multipoint welding method, wherein a welding gun portion is fixed on a support base. 13. The multi-point welding method according to claim 8, wherein the conductor comprises a plurality of cables formed of a flexible material so as to be flexible, and one end of the cable is provided with a first insulating member. The other end of the cable is connected to a first connecting member connected to one of the arms and a second connecting member connected to the other of the arms via a second insulating member. Multi-point welding method characterized by being performed. 14. The multi-point welding method according to claim 10, wherein the second welding gun portion electrically connected through the cable is constituted by up to four spot welding guns. Characteristic multi-point welding method.