KR101832740B1 - Brazing spot welding apparatus and welding method using the same - Google Patents

Brazing spot welding apparatus and welding method using the same Download PDF

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Publication number
KR101832740B1
KR101832740B1 KR1020150188983A KR20150188983A KR101832740B1 KR 101832740 B1 KR101832740 B1 KR 101832740B1 KR 1020150188983 A KR1020150188983 A KR 1020150188983A KR 20150188983 A KR20150188983 A KR 20150188983A KR 101832740 B1 KR101832740 B1 KR 101832740B1
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South Korea
Prior art keywords
bonded
electrode
welding
bonding
lower electrode
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KR1020150188983A
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Korean (ko)
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KR20170078455A (en
Inventor
김태현
이문용
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주식회사 성우하이텍
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Priority to KR1020150188983A priority Critical patent/KR101832740B1/en
Publication of KR20170078455A publication Critical patent/KR20170078455A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K11/00—Resistance welding; Severing by resistance heating
    • B23K11/10—Spot welding; Stitch welding
    • B23K11/11—Spot welding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K1/00—Soldering, e.g. brazing, or unsoldering
    • B23K1/0008—Soldering, e.g. brazing, or unsoldering specially adapted for particular articles or work
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K1/00—Soldering, e.g. brazing, or unsoldering
    • B23K1/14—Soldering, e.g. brazing, or unsoldering specially adapted for soldering seams
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K11/00—Resistance welding; Severing by resistance heating
    • B23K11/002—Resistance welding; Severing by resistance heating specially adapted for particular articles or work
    • B23K11/0026—Welding of thin articles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K11/00—Resistance welding; Severing by resistance heating
    • B23K11/36—Auxiliary equipment

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Resistance Welding (AREA)
  • Pressure Welding/Diffusion-Bonding (AREA)

Abstract

A spot brazing welding apparatus and a welding method are disclosed. A spot brazing welding apparatus according to an embodiment of the present invention includes a lower electrode having a lower cap tip mounted on a tip of a lower shank; And an upper cap tip is attached to the tip of the upper shank connected to the upper portion of the lower electrode corresponding to the upper portion of the lower electrode to apply a current so that heat is generated by the contact resistance generated between the upper electrode and the lower electrode, An upper electrode for bonding and forming a heat affected zone below the melting point; The upper shank and the upper cap are provided to penetrate the inside of the upper shank. The pressing force is applied by a pressing spring formed in the upper shank. The pressing force is applied to the inside of the bonding material below the melting point of the bonding material. To the heat affected zone formed at the interface between the materials to be bonded.
Further, in the welding method using the spot brazing welding apparatus, a material to be bonded is placed in a state in which two sheets of the sheet material are stacked between the lower electrode and the upper electrode; An electrode pressing step of moving and pressing the upper electrode against the upper surface of the bonding portion of the bonding material supported on the lower electrode; Heating the joining portion of the material to be bonded up to a point immediately before the melting point by using a resistance heat generated by applying a current to the joining portion of the joining material through the lower electrode and the upper electrode to form a heat affected portion therein; A penetration rod penetrating step of penetrating the bonding portion of the material to be bonded and penetrating into the heat affected portion by the pressing force of the pressing spring during the conduction heating step; A filler material injection step of injecting the filler supplied from the filler material supply means through the supply hose to the heat affected portion formed at the interface between the bonded materials through the penetrating rod; An electrode returning step of returning the upper electrode while applying a filler material to the hole on the bonding material formed by the penetrating rod; A filler material injection stop step of stopping the injection of the filler material while the penetrating rod is extracted from the material to be bonded; And a welding finishing step of finishing the welding through the cooling process for a predetermined time after the stopping of the sparging of the filler material.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a spot brazing welding apparatus,

The present invention relates to a spot brazing welding apparatus and a welding method. More particularly, the present invention relates to a spot brazing welding apparatus and a welding method. More particularly, the present invention relates to a spot brazing welding apparatus and welding method, To a spot brazing welding apparatus and a welding method which can shorten a process time and can eliminate a dimensional change of a product.

In general, laser welding using a laser beam output from a laser oscillator or electrical resistance welding using a spot welding machine is mainly applied to overlap two or more identical or dissimilar plate materials.

1 is a conceptual view for explaining spot brazing welding according to the prior art.

Referring to Fig. 1, recently, spot brazing is performed. First, a filler material 100 is first put into a brazing part between two sheets of the material to be bonded (P), and then both the two sheets of material are bonded to the upper electrode 101 A welding technique in which a current is flowed while being pressurized by the lower electrode 103 to bond the two sheets of the material to be bonded P to each other by the heat generated by the contact resistance and the pressing force is attracting attention.

This spot brazing welding is applied particularly to the method of joining dissimilar metal plates by using the filler material 100 which is the third metal.

Such conventional spot brazing welding requires the filler material 100 to be inserted in advance at the welding position between the two sheet materials to be joined since the filler material 100 is placed between the sheet material and the sheet material and pressurized and energized. 100) is added, so that the processing time is increased.

In addition, there is also a disadvantage in that a gap is formed between the plate material and the plate material due to the filler material 100, thereby causing a dimensional change of the plate material after the joining process.

The embodiment of the present invention can shorten the welding time by welding the two sheets of the plate material to be welded by injecting the filler into the interface between the plate materials through the penetration rod at an appropriate temperature during the spot welding process, And to provide a spot brazing welding apparatus and a welding method capable of preventing dimensional change after welding.

In one or more embodiments of the present invention, a lower electrode is constructed by mounting a lower cap tip on the tip of a lower shank; And an upper cap tip is attached to the tip of the upper shank connected to the upper portion of the lower electrode corresponding to the upper portion of the lower electrode to apply a current so that heat is generated by the contact resistance generated between the upper electrode and the lower electrode, An upper electrode for bonding and forming a heat affected zone below the melting point; The upper shank and the upper cap are provided to penetrate the inside of the upper shank. The pressing force is applied by a pressing spring formed in the upper shank. The pressing force is applied to the inside of the bonding material below the melting point of the bonding material. And a penetration rod for supplying the filler supplied through the gap between the bonding materials to the heat affected portion formed at the interface between the bonding materials.

In addition, the lower and upper cap tips may be made of chrome copper.

The lower and upper cap tips may be made of an iron-based metal material.

In addition, the filler may be provided in the form of a liquid or a paste or a powder so as to melt or penetrate into the heat-affected portion formed at the interface of the material to be bonded and mutually bond the materials to be welded.

The penetration rod may be made of an iron-based metal material.

Further, the pressing spring may have an elastic modulus set in accordance with the thickness of the member to be bonded.

The pressing spring may include a coil spring whose one end is supported by the pressing rod inside the upper shank and the other end is supported by the upper end of the penetrating rod.

The material to be bonded may be composed of two identical or different plates.

In the welding method using the spot brazing welding apparatus, a material to be bonded is placed in a state in which two sheet materials are superimposed between a lower electrode and an upper electrode; An electrode pressing step of moving and pressing the upper electrode against the upper surface of the bonding portion of the bonding material supported on the lower electrode; Heating the joining portion of the material to be bonded up to a point immediately before the melting point by using a resistance heat generated by applying a current to the joining portion of the joining material through the lower electrode and the upper electrode to form a heat affected portion therein; A penetration rod penetrating step of penetrating the bonding portion of the material to be bonded and penetrating into the heat affected portion by the pressing force of the pressing spring during the conduction heating step; A filler material injection step of injecting the filler supplied from the filler material supply means through the supply hose to the heat affected portion formed at the interface between the bonded materials through the penetrating rod; An electrode returning step of returning the upper electrode while applying a filler material to the hole on the bonding material formed by the penetrating rod; A filler material injection stop step of stopping the injection of the filler material while the penetrating rod is extracted from the material to be bonded; A welding method using a spot brazing welding apparatus including a welding completion step of completing welding through a cooling process for a certain period of time after the sparging of the sparging material is stopped can be provided.

In the sparging step, the heat affected zone formed at the interface between the materials to be bonded may be in a semi-molten state in which the solid phase and the liquid phase coexist due to resistance heat generated by the lower and upper electrodes.

In addition, in the sparging of the filler material, the filler may be provided in the form of a liquid or a paste or a powder so that the filler material may melt or penetrate into the heat-affected portion formed at the interface of the material to be bonded and mutually bond the welded materials.

In the embodiment of the present invention, the welding time can be shortened by injecting the filler through the penetrating rod to the interface between the plate materials at an appropriate temperature during the spot welding in the process of welding the two plate materials to be bonded.

Especially, it can be applied to the joining between two kinds of metal sheets due to the advantage of brazing welding using a joining material.

Further, since the welding is performed in an atmosphere in which the filler material is melted but the material to be welded is not completely melted, deformation and residual stress of the material to be welded are small.

Further, not the method of inserting the filler material between the materials to be bonded, but the method of spraying the material to the interface of semi-molten state between the materials to be bonded so that the gap between the plate materials as the material to be bonded is not opened, It is possible to secure a welding quality with high dimensional accuracy because there is no dimensional change.

1 is a conceptual view for explaining spot brazing welding according to the prior art.
2 is a configuration diagram of a spot brazing welding apparatus according to an embodiment of the present invention
3 is a process diagram of a welding method using a spot brazing welding apparatus according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In describing the method of joining the plated steel sheet of the present invention, the same reference numerals are applied to the same constituent elements as the conventional constitution.

2 is a configuration diagram of a spot brazing welding apparatus according to an embodiment of the present invention

2, a spot brazing welding apparatus according to an embodiment of the present invention includes a lower electrode 1, an upper electrode 3, a penetrating rod 5, Overlapping welding is performed in a state in which the plate members are overlapped.

The lower electrode 1 is configured such that a lower cap tip 13 is mounted on the tip of the lower shank 11.

The upper electrode 3 is formed by mounting an upper cap tip 25 on the tip of the upper shank 23 connected to the upper portion of the lower electrode 1 and connected to the pressing rod 21.

The upper electrode 3 applies a current so that the junction of the material to be bonded P is heated at a temperature lower than the melting point by heat generated by the contact resistance generated between the upper electrode 3 and the lower electrode 1, HT are formed and bonded.

Here, the lower cap tip 13 and the upper cap tip 25 may be made of chromium copper, which is basically used for spot welding. However, the present invention is not limited thereto. For heating the surface of the bonding material P, Can be configured.

The infiltration rod 5 is installed to penetrate the inside of the upper shank 23 and the upper cap tip 25 and is provided with a pressing force by a pressing spring 31 formed inside the upper shank 23, The filler material 7 that penetrates into the heat affected portion HT of the material to be bonded at the melting point of the bonding material P and is supplied from the external fugitive material supply means 35 through the supply hose 33 is sandwiched between the bonded materials P To the heat-affected zone HT formed at the interface of the heat-affected zone HT.

When the lower and upper cap tips (13, 25) are made of chrome copper, the permeable rods (5) are made of strong iron-based metal materials and can not only increase durability but also cause high- And helps penetration of the rod 5 to the material to be bonded (P).

The filler material 7 may be provided in the form of a liquid or a paste or a powder so as to melt or penetrate into the heat affected zone HT formed at the interface of the material to be bonded P and to bond the welded materials P to each other .

The pressing spring 31 may be a coil spring whose one end is supported by the pressing rod 21 in the upper shank 23 and the other end is supported by the upper end of the penetrating rod 5. [

The pressing spring 31 is set to have an elastic modulus in accordance with the thickness of the material to be bonded P. When the thickness of the material to be bonded P is changed,

That is, when the plate material to be bonded (P) is heated to form the heat affected zone (HT) at a certain temperature below the melting point, the pressure spring (31) Since the insertion depth is different according to the thickness of the plate, it is applied in a replacement manner so as to provide an appropriate pressing force.

3 is a process diagram of a welding method using a spot brazing welding apparatus according to an embodiment of the present invention.

Hereinafter, a welding method using a spot brazing welding apparatus according to an embodiment of the present invention will be described with reference to FIG.

First, a material feeding step (S1) for feeding a material to be bonded (P) in which two sheet materials are stacked between the lower electrode (1) and the upper electrode (3) is carried out.

The electrode pressing step S2 for moving the upper electrode 3 against the upper surface of the bonding portion of the bonding material P supported on the lower electrode 1 is performed.

Subsequently, the junction of the material to be bonded (P) is heated to just before the melting point by using a resistance heat generated by applying a current to the bonding portion of the bonding material (P) through the lower electrode (1) and the upper electrode The conductive heating step (S3) for forming the heat affected zone (HT) inside the bonded material (P) proceeds.

During the step S3 of the conduction heating step, the infiltration rod 5 penetrates the bonding portion of the material to be bonded P by the pressing force of the pressure spring 31 and penetrates into the heat affected portion HT, Step S4 is proceeded.

That is, when the sheet material to be bonded (P) is heated to form a heat affected zone (HT) reaching a certain temperature below the melting point, the pressing rod (31) When it reaches the level that can be put out, it penetrates the plate and penetrates into the inside.

When the penetrating rod 5 is infiltrated into the material to be bonded P as described above, the filler material 7 supplied from the filler material supply means 35 through the supply hose 33 through the penetration rod 5 is bonded to the material to be bonded P (S5), which is sprayed to the heat affected zone (HT) formed at the interface between the fuel cell

At this time, at the interface between the materials to be bonded (P), in the sparging material injecting step (S5), the heat affected by the lower electrode (1) and the upper electrode (3) And the filler material 7 is supplied in the form of a liquid or paste or powder so as to melt or penetrate into the heat affected portion HT of the material to be bonded P and to bond the materials to be bonded P together.

Thereafter, the electrode returning step S6 for applying the filler material 7 to the holes on the bonding material P formed by the permeable bar 5 and returning the upper electrode 3 is proceeded.

At this time, a filler material injection stop step (S7) for stopping the spraying of the filler material (7) is performed while the penetrating rod (5) is released from the material to be bonded (P) And a welding completion step (S8) for completing the welding through the welding process.

Therefore, according to the spot brazing welding apparatus and the welding method according to the embodiment of the present invention, the two sheet materials as the material to be bonded (P) penetrate into the heat-oriented portion (HT) formed at the interface between the sheet materials at the proper temperature during the spot welding It is possible to shorten the welding time by making the welding with the filler material 7 by injecting the filler material 7 by penetrating the rod 5 and in particular by the advantage of brazing welding with the filler material 7, There is an advantage that it can be applied to the joining of materials.

Further, since the filler material 7 is melted in the heat affected zone HT but the material to be bonded P is welded in an atmosphere in which the material P is not completely melted, there is an advantage that deformation and residual stress of the material to be bonded P are small.

In addition, as in the conventional method, the filler material 7 is not inserted between the materials to be bonded P, but is transferred to the heat affected portion HT between the materials to be bonded P, And there is no dimensional change caused by the existing filler (7) even after welding, so that welding quality with high dimensional precision can be secured.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. Various modifications and variations are possible within the scope of the appended claims.

1: Lower electrode
3: upper electrode
5: Penetration rod
7: Ingredient
11: Lower shank
13: Lower cap tip
21:
23: upper shank
25: Upper cap tip
31: Pressure spring
33: Supply hose
35: Filler supply means
HT: Heat affected zone
P: Bonded material

Claims (11)

A lower electrode having a lower cap tip mounted on a tip of a lower shank;
And an upper cap tip is attached to the tip of the upper shank connected to the upper portion of the lower electrode corresponding to the upper portion of the lower electrode to apply a current so that heat is generated by the contact resistance generated between the upper electrode and the lower electrode, An upper electrode for bonding and forming a heat affected zone below the melting point;
The upper shank and the upper cap are provided to penetrate the inside of the upper shank. The pressing force is applied by a pressing spring formed in the upper shank. The pressing force is applied to the inside of the bonding material below the melting point of the bonding material. To the thermally affected portion formed at the interface between the materials to be bonded;
And a welding device for welding the spot. The method according to claim 1,
The lower and upper cap tips
Spot brazing welding device made of chrome copper. The method according to claim 1,
The lower and upper cap tips
A spot brazing welding device comprising an iron-based metal material. The method according to claim 1,
The above-
And is provided in the form of a liquid or paste or powder so as to melt or penetrate into the heat affected portion formed at the interface of the material to be bonded and to bond the materials to be welded to each other. The method according to claim 1,
The infiltration rod
A spot brazing welding device comprising an iron-based metal material. The method according to claim 1,
The pressing spring
And an elastic modulus is set according to the thickness of the material to be bonded. The method according to claim 1,
The pressing spring
And a coil spring whose one end is supported by the pressing rod inside the upper shank and the other end is supported by the upper end of the penetration rod. The method according to claim 1,
The material to be bonded
A spot brazing welding device comprising two identical or different plates. A welding method using a spot brazing welding apparatus according to any one of claims 1 to 8,
A material feeding step of feeding a material to be bonded in a state in which two sheet materials are stacked between a lower electrode and an upper electrode;
An electrode pressing step of moving and pressing the upper electrode against the upper surface of the bonding portion of the bonding material supported on the lower electrode;
Heating the joining portion of the material to be bonded up to a point immediately before the melting point by using a resistance heat generated by applying a current to the joining portion of the joining material through the lower electrode and the upper electrode to form a heat affected portion therein;
A penetration rod penetrating step of penetrating the bonding portion of the material to be bonded and penetrating into the heat affected portion by the pressing force of the pressing spring during the conduction heating step;
A filler material injection step of injecting the filler supplied from the filler material supply means through the supply hose to the heat affected portion formed at the interface between the bonded materials through the penetrating rod;
An electrode returning step of returning the upper electrode while applying a filler material to the hole on the bonding material formed by the penetrating rod;
A filler material injection stop step of stopping the injection of the filler material while the penetrating rod is extracted from the material to be bonded;
A welding finishing step of finishing the welding by cooling the finishing material for a predetermined time after the sparging of the filler material is stopped;
Wherein the welding is performed using a spot brazing welding apparatus. 10. The method of claim 9,
Wherein the heat affected zone formed at the interface between the materials to be bonded is a semi-molten state in which the solid phase and the liquid phase coexist due to resistance heat generated by the lower and upper electrodes in the sparging material injecting step. 10. The method of claim 9,
In the sparging material injection step, the sparging material is welded using a spot brazing welding apparatus provided in the form of a liquid or paste or powder so as to be melted or penetrated into the heat affected portion formed at the interface of the material to be welded, .
KR1020150188983A 2015-12-29 2015-12-29 Brazing spot welding apparatus and welding method using the same KR101832740B1 (en)

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KR102394629B1 (en) * 2017-12-07 2022-05-06 현대자동차주식회사 Method for welding steel sheet made by hot stamping

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100902767B1 (en) 2008-01-02 2009-06-15 한종공업 주식회사 Spot welding machine with preventing overheating of cooling water for nut

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100902767B1 (en) 2008-01-02 2009-06-15 한종공업 주식회사 Spot welding machine with preventing overheating of cooling water for nut

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