JP5128159B2

Movatterモバイル変換

Info

Publication number: JP5128159B2
Application number: JP2007091468A
Authority: JP
Inventors: 彰後藤; 順也田辺
Original assignee: Honda Motor Co Ltd
Current assignee: Honda Motor Co Ltd
Priority date: 2007-03-30
Filing date: 2007-03-30
Publication date: 2013-01-23
Anticipated expiration: 2027-03-30
Also published as: JP2008246538A

Description

本発明は、抵抗溶接方法に関する。詳しくは、複数の板材を重ね合わせたワークをスポット溶接する抵抗溶接方法に関する。 The present invention relates to a resistance welding method. Specifically, the present invention relates to a resistance welding method for spot welding a workpiece in which a plurality of plate materials are overlapped.

従来より、自動車の製造工程では、複数枚の板材を重ねて抵抗溶接することが行われている。例えば、自動車のボディを製造する際には、剛性が高く厚い２枚のインナパネルと、このインナパネルよりも剛性が低く薄いアウタパネルと、を重ねて抵抗溶接する。
抵抗溶接では、複数枚の金属の板材を重ね合わせた溶接ワークを一対の電極間に挟んで加圧することにより局部的に接触面積を小さくする。そして、一対の電極間に電流を流すことで、この狭い接触面に大電流を流して、板材間の接触面に溶融部を生じさせる。
特開２００３−２５１４６９号公報Conventionally, in a manufacturing process of an automobile, a plurality of plate materials are stacked and resistance-welded. For example, when manufacturing an automobile body, two inner panels having a high rigidity and a thick inner panel and a thin outer panel having a lower rigidity than the inner panel are overlapped and resistance-welded.
In resistance welding, a contact area is locally reduced by pressing a welding work in which a plurality of metal plates are overlapped between a pair of electrodes. And by flowing an electric current between a pair of electrodes, a large electric current is caused to flow through this narrow contact surface, and a melted portion is generated at the contact surface between the plate members.
JP 2003-251469 A

しかしながら、上述のように、高剛性の２枚のパネルに重ねて低剛性のパネルを抵抗溶接する場合には、以下のような問題がある。 However, as described above, when resistance welding a low-rigidity panel over two high-rigidity panels, there are the following problems.

すなわち、高剛性の２枚のパネルを重ね、さらに、この２枚の高剛性のパネルの一方に低剛性のパネルを重ねて、溶接ワークを形成する。次に、一対の電極でこの溶接ワークを挟持すると、高剛性のパネル同士は撓んで互いに反り返り、これら高剛性のパネル同士の接触面積は小さくなる。これに対し、低剛性のパネルは、高剛性のパネルの一方に重ねて配置されているため、この高剛性のパネルになじんで変形する。その結果、低剛性のパネルと高剛性のパネルとの接触面積は、高剛性のパネル同士の接触面積に比べて大きくなり、低剛性のパネルと高剛性のパネルとの接触抵抗は、高剛性のパネル同士の接触抵抗よりも小さくなる。 That is, two high-rigidity panels are overlapped, and a low-rigidity panel is overlapped on one of the two high-rigidity panels to form a welded workpiece. Next, when this welding work is sandwiched between a pair of electrodes, the high-rigidity panels bend and warp each other, and the contact area between these high-rigidity panels decreases. On the other hand, since the low-rigidity panel is arranged so as to overlap one of the high-rigidity panels, it deforms in conformity with the high-rigidity panel. As a result, the contact area between the low rigidity panel and the high rigidity panel is larger than the contact area between the high rigidity panels, and the contact resistance between the low rigidity panel and the high rigidity panel is high. It becomes smaller than the contact resistance between panels.

したがって、この状態で電極間に通電すると、低剛性のパネルと高剛性のパネルとの間の発熱量は、高剛性のパネル間の発熱量よりも小さくなる。よって、高剛性のパネル同士を溶接できても、高剛性のパネルと低剛性のパネルとを確実に溶接できないおそれがあった。 Therefore, when electricity is applied between the electrodes in this state, the amount of heat generated between the low-rigidity panel and the high-rigidity panel is smaller than the amount of heat generated between the high-rigidity panels. Therefore, even if the high-rigidity panels can be welded together, there is a possibility that the high-rigidity panel and the low-rigidity panel cannot be reliably welded.

本発明は、剛性の異なる複数の板材を確実に溶接できる抵抗溶接方法を提供することを目的とする。 An object of this invention is to provide the resistance welding method which can weld reliably several board | plate materials from which rigidity differs.

本発明の抵抗溶接方法は、複数の板材を重ね合わせて溶接ワークとし、この溶接ワークを一対の電極で挟んだ状態で、当該一対の電極間に通電することで、前記溶接ワークを抵抗溶接する抵抗溶接方法であって、前記一対の電極間に通電中、当該一対の電極間の電流経路を横断するように磁場を生じさせることを特徴とする。 In the resistance welding method of the present invention, a plurality of plate materials are overlapped to form a welded workpiece, and the welded workpiece is resistance welded by energizing the pair of electrodes with the welded workpiece sandwiched between the pair of electrodes. In the resistance welding method, a magnetic field is generated so as to cross a current path between the pair of electrodes while the pair of electrodes is energized.

この発明によれば、一対の電極間に通電するとともに、これら一対の電極間の電流経路を横断するように磁場を生じさせた。よって、一対の電極間に流れる電流には、磁場によりローレンツ力が作用し、電流の経路が乱れて、電子の移動距離が長くなる。その結果、溶接ワークの内部抵抗が増大し、溶接ワークの内部の発熱が促進されることとなる。よって、板材の剛性が異なることにより接触面積が広くなる場合でも、板材の内部抵抗を増大して板材内部の発熱を促進できるから、これらの板材同士を確実に溶接できる。 According to the present invention, a current is applied between the pair of electrodes, and a magnetic field is generated so as to traverse the current path between the pair of electrodes. Therefore, the Lorentz force acts on the current flowing between the pair of electrodes due to the magnetic field, the current path is disturbed, and the moving distance of the electrons becomes long. As a result, the internal resistance of the welded workpiece increases and heat generation inside the welded workpiece is promoted. Therefore, even when the contact area is widened due to the difference in rigidity of the plate materials, the internal resistance of the plate materials can be increased and the heat generation inside the plate materials can be promoted, so that these plate materials can be reliably welded together.

この場合、前記磁場の強さおよび向きのうち少なくとも一方を変化させることが好ましい。 In this case, it is preferable to change at least one of the strength and direction of the magnetic field.

磁場の強さや向きを一定にすると、ローレンツ力の作用する方向が一定方向になってしまい、電子の移動経路を長くできないため、内部抵抗が大きくならず、発熱量を増大させることが困難となる。
しかしながら、この発明によれば、磁場の強さおよび向きのうち少なくとも一方を変化させたので、ローレンツ力の作用する方向が変化するので、電子の移動経路を長くすることができ、内部抵抗を大きくして、発熱量を増大できる。If the strength and direction of the magnetic field are made constant, the direction in which the Lorentz force acts becomes constant and the electron movement path cannot be lengthened, so the internal resistance does not increase and it is difficult to increase the amount of heat generation. .
However, according to the present invention, since at least one of the strength and direction of the magnetic field is changed, the direction in which the Lorentz force acts changes, so that the electron movement path can be lengthened and the internal resistance is increased. Thus, the heat generation amount can be increased.

本発明によれば、一対の電極間に通電するとともに、これら一対の電極間の電流経路を横断するように磁場を生じさせた。よって、一対の電極間に流れる電流には、磁場によりローレンツ力が作用し、電流の経路が乱れて、電子の移動距離が長くなる。その結果、溶接ワークの内部抵抗が増大し、溶接ワークの内部の発熱が促進されることとなる。 According to the present invention, a current is applied between the pair of electrodes, and a magnetic field is generated so as to traverse the current path between the pair of electrodes. Therefore, the Lorentz force acts on the current flowing between the pair of electrodes due to the magnetic field, the current path is disturbed, and the moving distance of the electrons becomes long. As a result, the internal resistance of the welded workpiece increases and heat generation inside the welded workpiece is promoted.

以下、本発明の実施形態を図面に基づいて説明する。
図１は、本発明の一実施形態に係る抵抗溶接方法が適用されたスポット溶接システム１の構成を示す図である。Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing a configuration of aspot welding system 1 to which a resistance welding method according to an embodiment of the present invention is applied.

スポット溶接システム１は、剛性の異なる複数の板材、ここでは３枚の板材を重ね合わせて形成された溶接ワーク２を抵抗溶接するものである。
ここで、溶接ワーク２は、金属製の板材としての厚板２１と、この厚板２１と剛性および厚みが等しい金属製の厚板２２と、厚板２１、２２よりも剛性が低く薄い金属製の板材としての薄板２３と、を重ね合わせて形成されている。Thespot welding system 1 resistance welds a plurality of plate materials having different rigidity, in this case, aweld work 2 formed by superposing three plate materials.
Here, thewelding work 2 includes athick plate 21 as a metal plate material, athick metal plate 22 having the same rigidity and thickness as thethick plate 21, and a thin metal having a lower rigidity than thethick plates 21 and 22. And athin plate 23 as a plate material.

スポット溶接システム１は、溶接ワーク２を抵抗溶接する抵抗溶接部３と、溶接ワーク２の内部に磁場を生じさせる磁場発生部４と、を備える。 Thespot welding system 1 includes aresistance welding part 3 for resistance welding thewelding work 2 and a magnetic field generation part 4 for generating a magnetic field inside thewelding work 2.

抵抗溶接部３は、溶接ワーク２を挟んで配置された一対の溶接電極３１、３２と、これら溶接電極３１、３２を互いに接近、離隔させる駆動機構３３と、溶接電極３１、３２に電流を供給する溶接電源３４と、を備える。
具体的には、溶接電極３１は、厚板２１側に配置され、溶接電極３２は、薄板２３側に配置されている。Theresistance welding part 3 supplies a current to the pair ofwelding electrodes 31 and 32 arranged with thewelding workpiece 2 sandwiched therebetween, thedrive mechanism 33 that moves thewelding electrodes 31 and 32 apart from each other, and thewelding electrodes 31 and 32. Awelding power source 34.
Specifically, thewelding electrode 31 is disposed on thethick plate 21 side, and thewelding electrode 32 is disposed on thethin plate 23 side.

図２は、磁場発生部４の構成を示す図である。
磁場発生部４は、電磁石であり、馬蹄形の芯部４１と、この芯部４１に電線が巻かれて形成されたコイル４２と、コイル４２に接続された電磁石用電源４３と、を備える。
芯部４１の両端は、磁極４１１、４１２であり、溶接ワーク２の薄板２３の表面上に溶接電極３２を挟んで配置される。
なお、磁極４１１、４１２は、直接、薄板２３に接触しておらず、溶接ワーク２の表面に対して絶縁されている。具体的には、磁極４１１、４１２と薄板２３との間に絶縁材４４が介装されている（図１参照）。なお、本実施形態では、絶縁材４４を介装したが、これに限らず、磁極４１１、４１２を薄板２３から離して配置してもよい。FIG. 2 is a diagram illustrating a configuration of the magnetic field generation unit 4.
The magnetic field generation unit 4 is an electromagnet, and includes a horseshoe-shaped core 41, acoil 42 formed by winding an electric wire around thecore 41, and anelectromagnet power supply 43 connected to thecoil 42.
Both ends of thecore portion 41 aremagnetic poles 411 and 412, and are arranged on the surface of thethin plate 23 of thewelding work 2 with thewelding electrode 32 interposed therebetween.
Themagnetic poles 411 and 412 are not in direct contact with thethin plate 23 and are insulated from the surface of thewelding workpiece 2. Specifically, an insulating material 44 is interposed between themagnetic poles 411 and 412 and the thin plate 23 (see FIG. 1). In this embodiment, the insulating material 44 is interposed. However, the present invention is not limited to this, and themagnetic poles 411 and 412 may be disposed away from thethin plate 23.

電磁石用電源４３は、交流電源であり、交流を供給することにより、磁極４１１、４１２間に磁場を発生させる。この磁力の変化を示す波形は、図３に示すように、サインカーブであり、磁場の強さや向きが常に変化する。 Theelectromagnet power supply 43 is an AC power supply, and generates a magnetic field between themagnetic poles 411 and 412 by supplying AC. The waveform indicating the change in magnetic force is a sine curve as shown in FIG. 3, and the strength and direction of the magnetic field always change.

以上のスポット溶接システム１の動作を説明する。
まず、図４に模式的に示すように、駆動機構３３を駆動して、溶接電極３１、３２で溶接ワーク２を加圧して、この溶接ワーク２を挟持する。The operation of the abovespot welding system 1 will be described.
First, as schematically shown in FIG. 4, thedriving mechanism 33 is driven to pressurize thewelding workpiece 2 with thewelding electrodes 31 and 32, and thewelding workpiece 2 is clamped.

すると、厚板２１、２２は撓んで互いに反り返り、これら厚板２１、２２同士の接触面積は、Ａ１となる。これに対し、薄板２３は、厚板２２に重ねて配置されているため、この厚板２２になじんで変形する。その結果、薄板２３と厚板２２との接触面積は、厚板２１、２２同士の接触面積Ａ１よりも大きいＡ２となり、薄板２３と厚板２２との接触抵抗は、厚板２１、２２同士の接触抵抗よりも小さくなる。 Then, thethick plates 21 and 22 bend and warp each other, and the contact area between thethick plates 21 and 22 is A1. On the other hand, since thethin plate 23 is disposed so as to overlap thethick plate 22, thethin plate 23 is deformed by being familiar with thethick plate 22. As a result, the contact area between thethin plate 23 and thethick plate 22 is A2 larger than the contact area A1 between thethick plates 21 and 22, and the contact resistance between thethin plate 23 and thethick plate 22 is between thethick plates 21 and 22. It becomes smaller than the contact resistance.

この状態で、図５に示すように、溶接電源３４を駆動して、溶接電極３１、３２間に通電するとともに、電磁石用電源４３を駆動して、磁極４１１、４１２間に磁場を生じさせる。すると、この磁場は、薄板２３内部において、溶接電極３１、３２間に流れる電流の経路を横断することになる。 In this state, as shown in FIG. 5, thewelding power source 34 is driven to energize thewelding electrodes 31 and 32, and theelectromagnet power source 43 is driven to generate a magnetic field between themagnetic poles 411 and 412. Then, this magnetic field traverses the path of the current flowing between thewelding electrodes 31 and 32 inside thethin plate 23.

すると、厚板２１、２２間の接触抵抗は、薄板２３と厚板２２との接触抵抗よりも大きいため、図６に示すように、主に厚板２１、２２間で発熱し、この厚板２１、２２間には、溶融部２４が生じる。 Then, since the contact resistance between thethick plates 21 and 22 is larger than the contact resistance between thethin plate 23 and thethick plate 22, heat is generated mainly between thethick plates 21 and 22, as shown in FIG. A meltedportion 24 is generated between 21 and 22.

また、磁極４１１、４１２間に生じた磁場は、薄板２３内部において、溶接電極３１、３２間の電流経路を横断するので、溶接電極３１、３２間を流れる電流には、磁場によりローレンツ力が作用する。よって、図７に模式的に示すように、薄板２３内部では、電流の経路が乱れて、電子の移動距離が長くなるので、薄板２３の内部抵抗が増大し、薄板２３の内部には、発熱により溶融部２５が生じる。 Further, since the magnetic field generated between themagnetic poles 411 and 412 traverses the current path between thewelding electrodes 31 and 32 inside thethin plate 23, the Lorentz force acts on the current flowing between thewelding electrodes 31 and 32 by the magnetic field. To do. Therefore, as schematically shown in FIG. 7, the current path is disturbed inside thethin plate 23, and the moving distance of electrons becomes long, so that the internal resistance of thethin plate 23 increases, and heat is generated inside thethin plate 23. As a result, a meltedportion 25 is generated.

その後、厚板２１、２２間に生じた溶融部２４は、次第に成長し、図８に示すように、薄板２３内部の溶融部２５まで到達する。その結果、図９に示すように、溶融部２４は、溶融部２５と完全に一体化し、薄板２３にも十分な溶け込みが得られる。 Thereafter, the meltedportion 24 generated between thethick plates 21 and 22 gradually grows and reaches the meltedportion 25 inside thethin plate 23 as shown in FIG. As a result, as shown in FIG. 9, themelting portion 24 is completely integrated with themelting portion 25, and sufficient penetration can be obtained in thethin plate 23.

本実施形態によれば、以下のような効果がある。
（１）溶接電極３１、３２間に通電するとともに、これら溶接電極３１、３２間の電流経路を横断するように磁場を生じさせた。よって、溶接電極間に流れる電流には、磁場によりローレンツ力が作用し、電流の経路が乱れて、電子の移動距離が長くなる。その結果、溶接ワーク２の内部抵抗が増大し、溶接ワーク２の内部の発熱が促進されることとなる。よって、厚板２２と薄板２３との剛性が異なることにより接触面積が広くなっても、薄板２３の内部抵抗を増大して薄板２３内部の発熱を促進できるから、これらの板材２１、２２、２３を確実に溶接できる。According to this embodiment, there are the following effects.
(1) While energizing between thewelding electrodes 31, 32, a magnetic field was generated so as to cross the current path between thewelding electrodes 31, 32. Therefore, the Lorentz force acts on the current flowing between the welding electrodes due to the magnetic field, the current path is disturbed, and the moving distance of electrons becomes long. As a result, the internal resistance of thewelding workpiece 2 increases, and the heat generation inside thewelding workpiece 2 is promoted. Therefore, even if the contact area is widened due to the difference in rigidity between thethick plate 22 and thethin plate 23, the internal resistance of thethin plate 23 can be increased and the heat generation inside thethin plate 23 can be promoted. Therefore, theseplate materials 21, 22, 23 Can be reliably welded.

（２）磁場発生部４により、磁力をサインカーブに沿って変化させたので、磁場の強さや向きが常に変化し、ローレンツ力の作用する方向が常に変化するから、電子の移動経路を長くすることができ、内部抵抗を大きくして、薄板２３内部での発熱量を増大できる。 (2) Since the magnetic force is changed along the sine curve by the magnetic field generator 4, the strength and direction of the magnetic field always change, and the direction in which the Lorentz force acts always changes, so the electron movement path is lengthened. The internal resistance can be increased, and the amount of heat generated in thethin plate 23 can be increased.

なお、本発明は前記実施形態に限定されるものではなく、本発明の目的を達成できる範囲での変形、改良等は本発明に含まれるものである。
例えば、上述の実施形態では、磁場における磁力の波形をサインカーブとしたが、これに限らず、矩形状としてもよい。It should be noted that the present invention is not limited to the above-described embodiment, and modifications, improvements, etc. within a scope that can achieve the object of the present invention are included in the present invention.
For example, in the above-described embodiment, the waveform of the magnetic force in the magnetic field is a sine curve, but the present invention is not limited to this and may be a rectangular shape.

また、本実施形態では、厚板２１、２２間に生じた溶融部２４を成長させて、薄板２３内部の溶融部２５まで到達させたが、これに限らない。すなわち、溶接電源３４および電磁石用電源４３を調整することにより、厚板２１、２２間に生じた溶融部２４だけではなく、薄板２３内部の溶融部２５も成長させて、これら溶融部２４と溶融部２５とを一体化させてもよい。 Further, in the present embodiment, the meltedportion 24 generated between thethick plates 21 and 22 is grown and reaches the meltedportion 25 inside thethin plate 23, but is not limited thereto. That is, by adjusting thewelding power source 34 and theelectromagnet power source 43, not only themelting part 24 generated between thethick plates 21 and 22, but also themelting part 25 inside thethin plate 23 is grown, Theunit 25 may be integrated.

また、本実施形態では、３枚の板材２１、２２、２３を重ね合わせて溶接ワーク２を形成したが、これに限らない。例えば、溶接ワークを２枚の板材で形成してもよい。具体的には、図１０に示すように、溶接ワーク２Ａを、厚板５１と、この厚板５１よりも剛性が低く薄い薄板５２と、を重ね合わせて形成する。そして、この溶接ワーク２Ａを溶接電極３１、３２で挟持し、溶接電極３１、３２間に通電するとともに、磁極４１１、４１２間に磁場を生じさせる。すると、厚板５１と薄板５２との間で発熱するとともに、薄板５２の内部でも発熱し、薄板５２の内部から厚板５１に亘って溶融部２６が発生する。 Moreover, in this embodiment, although the three board |plate materials 21, 22, and 23 were piled up and thewelding workpiece 2 was formed, it does not restrict to this. For example, the welding workpiece may be formed of two plate materials. Specifically, as shown in FIG. 10, thewelding work 2 </ b> A is formed by superposing athick plate 51 and athin plate 52 having a rigidity lower than that of thethick plate 51. Then, thewelding workpiece 2A is sandwiched between thewelding electrodes 31 and 32, energized between thewelding electrodes 31 and 32, and a magnetic field is generated between themagnetic poles 411 and 412. Then, heat is generated between thethick plate 51 and thethin plate 52, and heat is also generated inside thethin plate 52, and themelting part 26 is generated from the inside of thethin plate 52 to thethick plate 51.

本発明の一実施形態に係る抵抗溶接方法が適用されたスポット溶接システムの構成を示す図である。It is a figure which shows the structure of the spot welding system to which the resistance welding method which concerns on one Embodiment of this invention was applied.前記実施形態に係るスポット溶接システムの磁場発生部の構成を示す図である。It is a figure which shows the structure of the magnetic field generation part of the spot welding system which concerns on the said embodiment.前記実施形態に係るスポット溶接システムの磁場発生部により発生する磁力の変化を示す図である。It is a figure which shows the change of the magnetic force generated by the magnetic field generation part of the spot welding system which concerns on the said embodiment.前記実施形態に係るスポット溶接システムの駆動機構により溶接ワークを加圧した状態を示す模式図である。It is a schematic diagram which shows the state which pressurized the welding workpiece with the drive mechanism of the spot welding system which concerns on the said embodiment.前記実施形態に係るスポット溶接システムの溶接電極間に通電した状態を示す図である。It is a figure which shows the state which electrically supplied between the welding electrodes of the spot welding system which concerns on the said embodiment.前記実施形態に係るスポット溶接システムにより溶接ワークに溶融部を発生させた状態を示す図である。It is a figure which shows the state which generated the fusion | melting part in the welding workpiece with the spot welding system which concerns on the said embodiment.前記実施形態に係るスポット溶接システムの溶接電極間の電流経路を示す模式図である。It is a schematic diagram which shows the current pathway between the welding electrodes of the spot welding system which concerns on the said embodiment.前記実施形態に係るスポット溶接システムにより溶融部を成長させた状態を示す図である。It is a figure which shows the state which grew the fusion | melting part with the spot welding system which concerns on the said embodiment.前記実施形態に係るスポット溶接システムにより溶接が完了した状態を示す図である。It is a figure which shows the state which welding was completed by the spot welding system which concerns on the said embodiment.本発明の変形例に係る抵抗溶接方法が適用されたスポット溶接システムにより溶融部を発生させた状態を示す図である。It is a figure which shows the state which generated the fusion | melting part with the spot welding system to which the resistance welding method which concerns on the modification of this invention was applied.

符号の説明Explanation of symbols

２溶接ワーク
２１、２２厚板（板材）
２３薄板（板材）
３１、３２溶接電極（電極）

2 Weldingwork 21, 22 Thick plate (plate material)
23 Thin plate (plate material)
31, 32 Welding electrode (electrode)

Claims

Translated fromJapanese

複数の板材を重ね合わせて溶接ワークとし、この溶接ワークを一対の電極で挟んだ状態で、当該一対の電極間に通電することで、前記溶接ワークを抵抗溶接する抵抗溶接方法であって、
前記一対の電極間に通電中、当該一対の電極間の電流経路を横断するように磁場を生じさせることを特徴とする抵抗溶接方法。A resistance welding method for resistance welding the welded workpiece by energizing between the pair of electrodes in a state where a plurality of plate materials are overlapped to form a welded workpiece and the welded workpiece is sandwiched between the pair of electrodes,
A resistance welding method, wherein a magnetic field is generated so as to cross a current path between the pair of electrodes during energization between the pair of electrodes.

請求項１に記載の抵抗溶接方法において、
前記一対の電極間に通電中、前記磁場の強さおよび向きのうち少なくとも一方を変化させることを特徴とする抵抗溶接方法。
The resistance welding method according to claim 1,
A resistance welding method characterized by changing at least one of the strength and direction of the magnetic fieldduring energization between the pair of electrodes .