JP2008073728A - Joining method of metallic member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joining method by which joining can be carried out with stable quality even when materials of members to be joined are different from each other and when minute members are to be joined that are difficult by the conventional parallel gap welding. <P>SOLUTION: On the surface of at least one of the two members 2, 3 to be joined, there is preliminarily formed the plating layer of a metallic material having a melting point lower than that of the one member. The two members are stacked with the plating layer 6 interposed in-between, two electrodes 1a, 1b set in parallel with each other with a prescribed interval are pressed against the members, power is supplied to the electrodes, the plating layer is melted through resistive heat generation of the members, and the two members are joined. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

本発明は、小物部品やさらには微細な部品の接合に関し、特に、線径または幅１．０ｍｍ以下のリードワイヤを回路基板のランドやターミナル等に接合を行う接合方法に関する。   The present invention relates to joining of small parts and even fine parts, and more particularly, to a joining method for joining a lead wire having a wire diameter or width of 1.0 mm or less to a land or terminal of a circuit board.

従来、基板上のパターンやランド部に端子やリードワイヤ等を接合する方法として、ハンダ付けが一般的に用いられているが、ハンダ付けは、工程の時間短縮に限界があり、また、１５０℃以上の高温の環境にさらされる部位には使用できない問題がある。
これに対し、短時間で接合でき、かつ高温にさらされる部材の接合に利用できる方法として、特許文献１に示されるようなパラレルギャップ溶接方法が知られている。
この溶接方法は、溶接ヘッドに、互いに絶縁された２本の電極を狭い間隔で平行に取り付け、これら電極で重ね合わせて配置された被溶接部材を加圧しつつ、電極間に溶接電流を流すことにより発生する抵抗発熱を利用して溶接する方法である。 Conventionally, soldering is generally used as a method for joining terminals, lead wires, etc. to a pattern or land on a substrate. However, soldering has a limit in shortening the process time, and 150 ° C. There is a problem that it cannot be used for the parts exposed to the above high temperature environment.
On the other hand, a parallel gap welding method as shown in Patent Document 1 is known as a method that can be used for joining members that can be joined in a short time and exposed to high temperatures.
In this welding method, two electrodes that are insulated from each other are attached to a welding head in parallel at a narrow interval, and a welding current is passed between the electrodes while pressurizing a member to be welded that is superposed by these electrodes. It is a method of welding using the resistance heat generated by.

このパラレルギャップ溶接により、導電性の異なる２つの部材を溶接するような場合、例えば、基板上のステンレス鋼製のターミナルに銅製のリードを溶接する場合、溶接電流を供給する側の電極を、導電性の低い方の部材に押し当てる方法と高い方の部材に当てる方法のいずれかによって溶接が行われる。   When two members having different electrical conductivities are welded by this parallel gap welding, for example, when welding a copper lead to a stainless steel terminal on a substrate, the electrode on the side supplying the welding current is made conductive. Welding is performed by either a method of pressing against a member having a lower property or a method of pressing against a member having a higher property.

図６（ａ）は、溶接電流を供給する側の電極１ａを、導電性の低い方のターミナル３に押し当てる場合を示す。
基板４上のターミナル３の上にリード２を重ね合わせ、電極１ａでターミナル３を加圧力ａで加圧するとともに、溶接部を形成する側の電極１ｂによって、リード２を加圧力ｂで加圧する。この場合、電極１ｂの下部に溶融部５を形成してターミナル３とリード２を溶接するために、電極１ａの加圧力ａを電極１ｂの加圧力ｂよりも高めに設定しするとともに、ターミナル３とリード２の合わせ面にプロジェクション（突起）を形成して両者の接触抵抗を高め、なおかつ、電極１ａに導電性の良いクロム銅（ＣｒＣｕ）を用いるのに対して、電極１ｂをモリブデンまたはタングステンなどの電気抵抗が高く熱伝導の悪い材質にして、溶接部で発生した熱が電極を通して逃げないようして工夫して溶接する。 FIG. 6A shows a case where the electrode 1a on the side where the welding current is supplied is pressed against the terminal 3 having the lower conductivity.
The lead 2 is superposed on the terminal 3 on the substrate 4 and the terminal 3 is pressurized with the applied pressure a by the electrode 1a, and the lead 2 is pressurized with the applied pressure b by the electrode 1b on the side where the weld is formed. In this case, in order to form the melted portion 5 below the electrode 1b and weld the terminal 3 and the lead 2, the pressing force a of the electrode 1a is set higher than the pressing force b of the electrode 1b, and the terminal 3 A projection (protrusion) is formed on the mating surface of the lead 2 and the contact resistance between the two is increased, and the electrode 1b is made of chromium copper (CrCu) having good conductivity, whereas the electrode 1b is made of molybdenum or tungsten. A material with high electrical resistance and poor heat conduction is devised so that heat generated at the weld does not escape through the electrodes.

また、図６（ｂ）は、電極１ａと電極１ｂをともに導電性の高い方のリード２に押し当てる場合を示す。
ターミナル３上へのリード２の重ね合わせ部分を長くし、電極１ａと溶接側の電極１ｂによって、リード２をターミナル３に加圧する。この場合も、各電極の材質や加圧力の設定は、（ａ）の場合と同様にする。溶接電流を電気抵抗の低いリード２から供給するため、溶接電流はリード２に多く流れ、ターミナル３に流れる電流は少ない。このため、（ａ）と同様、溶接側の電極１ｂにモリブデン又はタングステンを用い、かつ加圧力ｂを加圧力ａより低く設定して、電極１ｂとリード２の接触抵抗で発熱させ、その熱を溶接部に伝えて溶接をする。 FIG. 6B shows a case where both the electrode 1a and the electrode 1b are pressed against the lead 2 having higher conductivity.
The overlapping portion of the lead 2 on the terminal 3 is lengthened, and the lead 2 is pressed against the terminal 3 by the electrode 1a and the electrode 1b on the welding side. Also in this case, the setting of the material and the applied pressure of each electrode is the same as in the case of (a). Since the welding current is supplied from the lead 2 having a low electrical resistance, the welding current flows through the lead 2 and the current flowing through the terminal 3 is small. For this reason, as in (a), molybdenum or tungsten is used for the electrode 1b on the welding side, and the applied pressure b is set lower than the applied pressure a, and heat is generated by the contact resistance between the electrode 1b and the lead 2, and the heat is Tell the weld and weld.

以上のような従来のパラレルギャップ溶接方法では下記のような問題がある。
（１）２つの電極の加圧力の設定などにおいて、溶接品質が確保できる条件範囲が狭く、安定した溶接を行うことが困難である。
（２）溶接側の電極は高温にさらされるため電極の寿命も短く、かつその熱によって溶接部以外の部分が不必要に加熱される。
（３）所要の抵抗発熱を行うためにはある程度の電極間隔Ｌが必要であり、微細な部材の溶接が出来ない。
（４）溶接側の電極と被溶接部材の接触部分も高温に加熱されるため、溶接後に被溶接部材の電極への張り付きが発生し、電極の定期的な研磨が必要となる。 The conventional parallel gap welding method as described above has the following problems.
(1) In setting the pressurizing force of two electrodes, the condition range in which welding quality can be ensured is narrow, and it is difficult to perform stable welding.
(2) Since the electrode on the welding side is exposed to a high temperature, the life of the electrode is short, and parts other than the welded portion are unnecessarily heated by the heat.
(3) A certain amount of electrode spacing L is required to perform the required resistance heat generation, and fine members cannot be welded.
(4) Since the contact portion between the electrode on the welding side and the member to be welded is also heated to a high temperature, sticking of the member to be welded to the electrode occurs after welding, and it is necessary to periodically polish the electrode.

特開２００３−４８０７３号公報JP 2003-48073 A

そこで、本発明は、パラレルギャップ溶接技術を用いた接合方法において、上記のような問題点を解決し、接合しようとする部材の材質が異なる場合や従来のパラレルギャップ溶接では接合が困難な微細な部材の場合でも安定した品質で接合が可能な接合方法を提供することを課題とする。   Therefore, the present invention solves the above-described problems in the joining method using the parallel gap welding technique, and it is difficult to join in the case where the materials of the members to be joined are different or the conventional parallel gap welding. It is an object of the present invention to provide a joining method capable of joining with stable quality even in the case of members.

上記の課題を解決するために、本発明は次のようにしたことを特徴とする。
請求項１の発明は、接合しようとする２つの部材の少なくとも一方の部材の表面に、あらかじめ該部材の材料の融点よりも低い融点を有する金属材料のメッキ層を形成し、該２つの部材をメッキ層を間に介在させて重ね合わせ、所定の間隔を置いて平行にセットされた２本の電極を該部材に押し当て、電極間に通電して部材の抵抗発熱により前記メッキ層を溶融させて２つの部材を接合することを特徴とする。 In order to solve the above problems, the present invention is characterized as follows.
In the invention of claim 1, a plating layer of a metal material having a melting point lower than the melting point of the material of the member is previously formed on the surface of at least one of the two members to be joined, Two layers of electrodes are placed on top of each other with a predetermined interval between them, and two electrodes set parallel to each other are pressed against the member, and the plating layer is melted by resistance heating of the member by energizing between the electrodes. The two members are joined together.

この発明によれば、融点の低いメッキ層を溶融させて接合するため、従来のパラレルギャップ溶接方法よりも溶融に必要な発熱量を小さくできる。そのため、（イ）電極間隔を狭く設定でき、製品の接合部の寸法を小さく設計できるので、部品の小型化、高密度化が可能となり、（ロ）発熱部分を小さくできるために他部品への熱影響を最小限にでき、（ハ）電極温度が比較的低いため電極寿命が長くできる、という効果が得られる。さらに、この発明によれば、（ニ）主としてメッキ層の溶融による接合のため、接合部の形状変化が少なくきれいな仕上がりが可能であり、（ホ）接合しようとする部材の材質が異なっていても、加圧力は左右の電極で同一でよく、しかも、加圧力の変動による接合品質への影響は小さいのでその設定が容易である、という効果が得られる。   According to the present invention, since the plating layer having a low melting point is melted and joined, the calorific value necessary for melting can be reduced as compared with the conventional parallel gap welding method. Therefore, (a) the electrode spacing can be set narrow, and the dimensions of the product joint can be designed to be small, so that the parts can be made smaller and denser. Thermal effects can be minimized, and (c) the electrode life can be increased because the electrode temperature is relatively low. Further, according to the present invention, (d) because the joining is mainly performed by melting of the plating layer, the shape of the joined part is small and a beautiful finish is possible. (E) Even if the materials of the members to be joined are different The applied pressure may be the same for the left and right electrodes, and since the influence on the joining quality due to fluctuations in the applied pressure is small, an effect that the setting is easy is obtained.

請求項２の発明は、請求項１の発明において、さらに、接合しようとする２つの部材の材質が異なっており、導電性の高い方の部材に前記メッキ層を形成して、その部材を電極側に配置したことを特徴とする。
この発明によれば、接合しようとする２つの部材の材質が異なる場合においても、上記従来のような問題もなく確実に接合することができる。 According to a second aspect of the present invention, in the first aspect of the present invention, the materials of the two members to be joined are different, the plated layer is formed on the member having higher conductivity, and the member is used as an electrode. It is arranged on the side.
According to the present invention, even when the materials of the two members to be joined are different, the joining can be surely performed without the above-described problems.

請求項３の発明は、請求項１、２の発明において、さらに、接合しようとする一方の部材が銅または銅合金よりなり、該部材の表面に銀または銀合金よりなるメッキ層が形成されていることを特徴とする。
この発明によれば、基板上のランド部などにリードワイヤを接合する場合など、最適な条件で接合することができる。 According to a third aspect of the present invention, in the first and second aspects of the present invention, one member to be joined is made of copper or a copper alloy, and a plated layer made of silver or a silver alloy is formed on the surface of the member. It is characterized by being.
According to the present invention, bonding can be performed under optimum conditions such as when a lead wire is bonded to a land portion or the like on a substrate.

請求項４の発明は、請求項１〜３の発明において、さらに、メッキ層をそれぞれ母部材の表面に形成することをことを特徴とする。
この発明によれば、接合しにくい部材に対しても確実に接合することができる。 According to a fourth aspect of the present invention, in the first to third aspects of the present invention, the plating layer is further formed on the surface of the base member.
According to this invention, it is possible to reliably join even a member that is difficult to join.

請求項５の発明は、請求項１〜４の発明において、さらに、電極間に冷却部材を配置し、それぞれの電極から加熱部材に向けて電流を供給して、それぞれの電極と冷却部材の間で、メッキ層を溶融させることを特徴とし、請求項６の発明は、同じく、電極間に補助電極を配置し、補助電極からそれぞれの電極に向けて電流を供給して、それぞれの電極と補助電極の間で、前記メッキ層を溶融させることを特徴とする。
これらの発明によれば、部材を複数箇所で接合することができ、より強固に接合することができる。 According to a fifth aspect of the present invention, in the first to fourth aspects of the present invention, a cooling member is further disposed between the electrodes, current is supplied from the respective electrodes toward the heating member, and between the respective electrodes and the cooling member. The invention according to claim 6 is also characterized in that the auxiliary electrode is disposed between the electrodes, and an electric current is supplied from the auxiliary electrode to each electrode to assist each electrode and the auxiliary electrode. The plating layer is melted between the electrodes.
According to these inventions, the members can be joined at a plurality of locations, and can be joined more firmly.

本発明は、パラレルギャップ溶接技術を用い、図６を用いて説明したように従来の方法では種々問題のある、２つの被接合部材が導電率の異なる材質よりなる場合、あるいは、被接合部材が微細で重ね合せ部が長く取れないような場合でも、低い発熱温度で短い電極間距離で接合が行えるようにするとともに、左右の電極の加圧力を同じにして、容易に接合が行えるようにした。
そのために本発明では、接合しようとする２つの部材の少なくとも一方の部材の表面に、あらかじめ該部材の材料の融点よりも低い融点を有する金属材料のメッキ層を形成しておき、そのメッキ層を溶融させて２つの部材を接合するようにした。 The present invention uses the parallel gap welding technique, and there are various problems in the conventional method as described with reference to FIG. 6. When the two members to be joined are made of materials having different conductivities, or the members to be joined are Even when it is fine and the overlapping part cannot be removed for a long time, it is possible to perform bonding with a low exothermic temperature and a short distance between the electrodes, and the pressure applied to the left and right electrodes can be the same to facilitate bonding. .
Therefore, in the present invention, a plating layer of a metal material having a melting point lower than the melting point of the material of the member is formed in advance on the surface of at least one member of the two members to be joined. The two members were joined by melting.

以下、基板４上の導電性の低いターミナル３（ステンレス鋼製）と導電性の高いリードワイヤ２（銅製）との接合を例に、図１を用いて本発明の態様を詳細に説明する。   Hereinafter, an embodiment of the present invention will be described in detail with reference to FIG. 1 by taking as an example the joining of a terminal 3 (made of stainless steel) having low conductivity on a substrate 4 and a lead wire 2 (made of copper) having high conductivity.

本発明では、リードワイヤ２の接合しようとする表面を、銅よりも融点の低い材料、例えば銀でメッキしておき、それをターミナル３の表面に重ね合わせる。このときメッキ層６がリードワイヤ２とターミナル３の間に介在されるようにする。   In the present invention, the surface to be joined of the lead wire 2 is plated with a material having a melting point lower than that of copper, for example, silver, and is superposed on the surface of the terminal 3. At this time, the plating layer 6 is interposed between the lead wire 2 and the terminal 3.

次いで所定の間隔を置いて平行にセットされた左右の電極１ａ、１ｂをリードワイヤ２の表面に押し当てて加圧する。このときの加圧力ａ、ｂは左右の電極で同じでよい。加圧力が所定の値に到達したらすぐに電極間に通電する。このとき、電流は破線で示すように電極１ａから導電性の高いリードワイヤ２を通って電極１ｂに流れる。この電流によって電極間ではさまれたリードワイヤの部分が抵抗発熱する。その発熱によってリードワイヤ表面のメッキ層が溶融し、さらに、電極の加圧力によって下側にあるターミナル３に熱の伝導とともにメッキの金属が流れ、両者の隙間を埋めるとともに、両者の材料内に拡散しする。
メッキ層が溶融後、通電を終了させると、発生した熱は電極により急速に冷却され、溶融したメッキの金属が凝固し、リードワイヤ２とターミナル３は接合部７で接合される。 Next, the left and right electrodes 1a and 1b set in parallel at a predetermined interval are pressed against the surface of the lead wire 2 and pressed. The applied pressures a and b at this time may be the same for the left and right electrodes. As soon as the applied pressure reaches a predetermined value, electricity is applied between the electrodes. At this time, current flows from the electrode 1a through the highly conductive lead wire 2 to the electrode 1b as indicated by a broken line. The portion of the lead wire sandwiched between the electrodes by this current generates resistance heat. Due to the heat generation, the plating layer on the lead wire surface melts, and further, the metal of the plating flows along with the conduction of heat to the terminal 3 on the lower side by the applied pressure of the electrode, fills the gap between the two, and diffuses into both materials To do.
When energization is terminated after the plating layer is melted, the generated heat is rapidly cooled by the electrodes, the molten plating metal is solidified, and the lead wire 2 and the terminal 3 are joined at the joint 7.

このとき、リードワイヤ２の電極１ａ、１ｂに接している部分は、電極１ａへの伝熱で冷却されるので、接合部以外の熱影響を最小にすることができる。また、メッキ層をろう材のように溶融して接合するので接合部の形状変化が少なく、接合部をきれいな状態で仕上げることができる。   At this time, the portions of the lead wire 2 that are in contact with the electrodes 1a and 1b are cooled by heat transfer to the electrode 1a, so that the heat influence other than the joint can be minimized. In addition, since the plating layer is melted and joined like a brazing material, the shape of the joint is hardly changed, and the joint can be finished in a clean state.

以上のように本発明では、従来のパラレルギャップ溶接のようにリードワイヤとターミナルの加圧接触部を溶融するのではなく、電極間のメッキ層を溶融させて接合する。メッキ層の材料の融点は接合しようとする部材の融点より低いため（銅の融点が１０８３℃で、銀の融点が９６２℃）、メッキ層を溶融させるために必要な発熱量は、従来の方法よりも小さくてよく、電極間距離Ｌを、０．０５〜１．０ｍｍの短い範囲で設定できる。また、電極間で溶融させるため、左右電極の加圧力ａ、ｂも同じにできる。   As described above, in the present invention, the pressure contact portion between the lead wire and the terminal is not melted as in the conventional parallel gap welding, but the plating layer between the electrodes is melted and joined. Since the melting point of the material of the plating layer is lower than the melting point of the members to be joined (the melting point of copper is 1083 ° C. and the melting point of silver is 962 ° C.), the calorific value necessary for melting the plating layer is the conventional method. The inter-electrode distance L can be set in a short range of 0.05 to 1.0 mm. Further, since the electrodes are melted, the applied pressures a and b of the left and right electrodes can be made the same.

また、本発明では、電極間のメッキ層をろう材のように用いてそれを溶融させて接合するため、メッキに用いられる金属材料としては、接合しようとする部材の材料よりも融点の低い材料を用いる。銅製のリードワイヤの場合は上記のように銀が好適である。
他方の部材の材料がメッキ金属と接合性の悪い場合には、接合しようとする部材のそれぞれにメッキ層を形成するのが好ましい。その際、メッキ金属との付着性が悪い場合には、メッキする部材の金属とメッキ金属の両方になじみのよい金属で下地メッキを施し、その上に所定のメッキ金属でメッキするのがよい。図１の例で、ステンレス鋼のターミナルにも銀のメッキ層を形成する場合は、直接銀メッキをするよりは、Ｎｉの下地メッキの上に銀メッキをするとより付着性を高めることができる。 In the present invention, since the plating layer between the electrodes is used like a brazing material and is melted and joined, the metal material used for plating is a material having a lower melting point than the material of the member to be joined. Is used. In the case of copper lead wires, silver is suitable as described above.
When the material of the other member is poorly bonded to the plated metal, it is preferable to form a plated layer on each member to be bonded. At that time, if the adhesion to the plating metal is poor, it is preferable to perform base plating with a metal that is familiar to both the metal of the member to be plated and the plating metal, and then to plate with a predetermined plating metal. In the example of FIG. 1, when a silver plating layer is also formed on a stainless steel terminal, the adhesion can be improved by silver plating on the Ni base plating rather than direct silver plating.

本発明は、基本的に従来のパラレルギャップ溶接装置を用いて実施できる。電極としては、狭い間隔をおいて平行に配置され、電極間が電気的に絶縁された左右一対の電極が用いられる。この電極の素材は、導電性、熱伝導性のよい銅またはクロム銅のような銅合金が好適である。   The present invention can basically be implemented using a conventional parallel gap welding apparatus. As the electrodes, a pair of left and right electrodes that are arranged in parallel at a narrow interval and are electrically insulated from each other are used. The electrode material is preferably copper or a copper alloy such as chrome copper having good conductivity and thermal conductivity.

電極の先端部は、接合しようとする部材の径や幅の１．３倍以上の長さを一辺とする四角形が好ましい。そうすることにより、多少の位置ズレでも吸収することができ、電極と部材の接触部の発熱を電極の熱容量と伝熱でより効果的に冷却することができる。
また、左右の電極の先端面は、部材に対して接触抵抗を一様にして押し当てることができるように、例えば電極を垂直に設置した場合、最下端が水平方向に対し同一レベルになるように配置させる。 The tip of the electrode is preferably a quadrangle with one side having a length of 1.3 times or more the diameter or width of the member to be joined. By doing so, even a slight misalignment can be absorbed, and the heat generation at the contact portion between the electrode and the member can be more effectively cooled by the heat capacity and heat transfer of the electrode.
Also, the tip surfaces of the left and right electrodes can be pressed against the member with a uniform contact resistance. For example, when the electrodes are installed vertically, the lowermost ends are at the same level in the horizontal direction. To place.

電極は、線径１．０ｍｍ以下のリードワイヤの場合、接触面に１ｍｍ²あたり４０から８０００ｇ程度の加圧力で押し付ける。その際の加圧力は、接合部材間が適度な接触圧で接触し、リードワイヤなどの接合部材に電流を安定して供給できるように、また、電極と接合部材との接触面での発熱を抑制し、かつ接合後に接合部材の冷却を助けることができるように設定される。加圧力は、加圧によって生じる変形が許容範囲に収まる範囲とするが、そのような変形を考慮してあらかじめ接合部に元の径（幅）の４０％以下の範囲で潰し加工をしたものを用いてもよい。 In the case of a lead wire having a wire diameter of 1.0 mm or less, the electrode is pressed against the contact surface with a pressure of about 40 to 8000 g per mm ² . The pressure applied at that time is such that the joining members are brought into contact with each other at an appropriate contact pressure, and a current can be stably supplied to the joining member such as a lead wire, and heat is generated at the contact surface between the electrode and the joining member. It sets so that it can suppress and can help cooling of a joining member after joining. The applied pressure is a range in which the deformation caused by the pressurization falls within an allowable range. However, in consideration of such a deformation, the joint is previously crushed in a range of 40% or less of the original diameter (width). It may be used.

電極の通電条件は、メッキ層を溶融させるのに必要な発熱量が得られるように設定する。必要な発熱量は、メッキ金属の融点や接合使用とする部材の形状、寸法、熱容量などに応じて決まるので、それに必要な電流、電圧、通電時間を設定する。   The energization conditions of the electrodes are set so as to obtain a calorific value necessary for melting the plating layer. The necessary amount of heat generation is determined according to the melting point of the plated metal, the shape, size, heat capacity, etc. of the member to be used for joining.

以上では１点で接合する方法を説明したが、より接合強度を有する製品の接合においては、複数の点で接合する必要が生じる。図２、３に示す例は、そのような場合に適用できる本発明の他の実施の態様を示す。   Although the method of joining at one point has been described above, it is necessary to join at a plurality of points in joining products having higher joining strength. The example shown in FIGS. 2 and 3 shows another embodiment of the present invention applicable to such a case.

図２は、電極１ａ、１ｂ間に、銅などの熱伝導率の高い材料でできた冷却部材８を配置した例を示す。この場合は、ターミナル３とリードワイヤ２の接合部を長く取る以外は、図１の場合と同様にリードワイヤ２の表面にメッキ層６を形成して両者を重ね合わせ、左右の電極１ａ、１ｂと冷却部材８とで、リードワイヤ２を加圧する。このとき、冷却部材の加圧力は、電極の加圧力と同じかそれ以下の加圧力とする。次いで、図の破線で示すように電極１ａから電極１ｂに電流を供給するが、リードワイヤ２の冷却部材８に接している部分は、該部材によって冷却されて温度が低下するので、その部分に隣接するメッキ層６は溶融せず、電極１ａと冷却部材８の間及び電極１ｂと冷却部材８の間で溶融が起こり、ターミナル３とリードワイヤ２は、その溶融部分７、７の２点で接合される。この方法では、冷却部材の数を増加させれば２点以上での接合も可能であるが、電極間隔は大きくなるという不利が生じる。   FIG. 2 shows an example in which a cooling member 8 made of a material having high thermal conductivity such as copper is disposed between the electrodes 1a and 1b. In this case, except that the joint between the terminal 3 and the lead wire 2 is made long, a plating layer 6 is formed on the surface of the lead wire 2 in the same manner as in FIG. And the cooling member 8 pressurize the lead wire 2. At this time, the pressure of the cooling member is the same as or less than the pressure of the electrode. Next, current is supplied from the electrode 1a to the electrode 1b as shown by the broken line in the figure. However, the portion of the lead wire 2 that is in contact with the cooling member 8 is cooled by the member and the temperature is lowered. The adjacent plating layer 6 does not melt, but melting occurs between the electrode 1a and the cooling member 8 and between the electrode 1b and the cooling member 8, and the terminal 3 and the lead wire 2 are at two points of the melting portions 7 and 7. Be joined. In this method, if the number of cooling members is increased, joining at two or more points is possible, but there is a disadvantage that the electrode interval is increased.

図３は、前記電極間に補助電極９を配置した例を示す。この場合も図２の場合と同様に、ターミナル３とリードワイヤ２をセットし、左右の電極１ａ、１ｂと補助電極９とで、リードワイヤ２を加圧する。このとき、補助電極の加圧力は、左右の電極の加圧力と同じかそれ以下の加圧力とする。そして、図の破線で示すようにそれぞれの電極１ａ、１ｂから補助電極に向けて電流を供給して、それぞれの電極と補助電極の間で、前記メッキ層を溶融させる。ターミナル３とリードワイヤ２は、その溶融部分７、７の２点で接合される。   FIG. 3 shows an example in which the auxiliary electrode 9 is arranged between the electrodes. Also in this case, as in the case of FIG. 2, the terminal 3 and the lead wire 2 are set, and the lead wire 2 is pressurized by the left and right electrodes 1a and 1b and the auxiliary electrode 9. At this time, the pressing force of the auxiliary electrode is the same as or less than the pressing force of the left and right electrodes. And as shown with the broken line of a figure, an electric current is supplied toward each auxiliary electrode from each electrode 1a, 1b, and the said plating layer is fuse | melted between each electrode and auxiliary electrode. The terminal 3 and the lead wire 2 are joined at two points of the melted portions 7 and 7 thereof.

以上のような本発明は、図４に示すパラレルギャップ溶接装置を用いて実施される。
装置の接合ヘッド１１には、電極１ａ、ｂがそれぞれホルダ１２ａ、ｂを介して取り付けられている。平行する二本の電極の間は電気的に絶縁されており、各電極は、二次導体１３ａ、ｂにより電源１０と接続されている。一対の電極の形状は同一であり、材質はいずれも導電性、伝熱性のよい銅または銅合金が用いられる。また接合ヘッド１１に装備される電極ホルダ１２ａ、ｂは、電極１ａ、ｂの交換と手入れが容易な構造となっており、また、熱伝導と電気的導通のよい材料で造られ電極の冷却作用も持つようにする。 The present invention as described above is carried out using the parallel gap welding apparatus shown in FIG.
Electrodes 1a and 1b are attached to the joining head 11 of the apparatus via holders 12a and 12b, respectively. Two parallel electrodes are electrically insulated from each other, and each electrode is connected to the power source 10 by secondary conductors 13a and 13b. The pair of electrodes has the same shape, and the material is copper or copper alloy having good conductivity and heat conductivity. Further, the electrode holders 12a and 12b provided in the joining head 11 have a structure in which the electrodes 1a and b can be easily exchanged and maintained, and are made of a material having good heat conduction and electrical conduction, and the cooling action of the electrodes. Also have.

接合に当たっては、まず、接合ヘッド１１は設定加圧に達するまで電極１ａ、ｂによってリードワイヤ２をターミナル３に押し付ける。一対の電極の加圧力が予め設定された加圧値に達すると、接合ヘッド１１に搭載されたリミットスイッチが作動し、検出信号を直ちに信号線１４を通して電源１０に送り、電源１０から一対の電極に対し、１〜２ｍｓの短時間に、およそ５Ｖ未満で２０〜３０００Ａ程度の電力が供給される。   In joining, first, the joining head 11 presses the lead wire 2 against the terminal 3 by the electrodes 1a and b until reaching the set pressure. When the pressing force of the pair of electrodes reaches a preset pressure value, a limit switch mounted on the bonding head 11 is activated, and a detection signal is immediately sent to the power source 10 through the signal line 14. On the other hand, in a short time of 1 to 2 ms, power of about 20 to 3000 A is supplied at about less than 5 V.

接合のための電流は、電極１ａからリードワイヤ２に供給され電極１ｂを通り電源１０に流れる。電流が流れるとリードワイヤの固有抵抗によって急速に内部発熱し、通電中にリードワイヤ２のメッキ層（図示せず）を瞬時に溶融させ、押し付けられたターミナル７と溶融接合される。
このとき、リードワイヤ２の電極１ａ、ｂに接している部分は、電極への伝熱で冷却され、発熱は抑制された状態となっている。 A current for bonding is supplied from the electrode 1a to the lead wire 2 and flows to the power source 10 through the electrode 1b. When an electric current flows, internal heat is rapidly generated due to the specific resistance of the lead wire, and a plated layer (not shown) of the lead wire 2 is instantaneously melted while being energized and melted and joined to the pressed terminal 7.
At this time, the portions of the lead wire 2 that are in contact with the electrodes 1a and 1b are cooled by heat transfer to the electrodes, and the heat generation is suppressed.

電源１０は、フィードバック機能（電極間電圧を一定にし、通電電流をセンシングして定電力となるよう電流を制御する機能）を持っており、通電中は常に安定した電力の供給がなされる。
通電終了後、溶融したリードワイヤ２のメッキ金属はターミナル３に押し付けられた状態で凝固する。
その後、接合ヘッド１１を操作し、接合ヘッド１１を原点位置に復帰させる。この時、電極先端はリードワイヤ２と容易に分離し次の工程に影響を与えないで移動できる。 The power supply 10 has a feedback function (a function of controlling the current so as to obtain constant power by sensing the energization current while keeping the voltage between the electrodes constant), and stable power supply is always performed during energization.
After the energization is completed, the molten plated metal of the lead wire 2 is solidified while being pressed against the terminal 3.
Thereafter, the bonding head 11 is operated to return the bonding head 11 to the origin position. At this time, the electrode tip is easily separated from the lead wire 2 and can move without affecting the next process.

図５に、本発明の接合に用いる電極形状の一例を示す。電極は中央の絶縁層１５を挟んで左右対称に配置され、かつ上下にスライドするように取り付けられる。絶縁層の厚さである電極間隔Ｌは約０．０５ｍｍ〜１．０ｍｍである。また、図５（ｂ）に示すように、電極の下端側から見た接触面１６の形状も絶縁層１５を挟み左右対象となっている。電極下端の接触面１６は平滑に仕上げられている。絶縁層１５の下端は電極の下端より内側に設定されており、その距離Ｈは０.５〜５．０ｍｍである。電極の端部の幅Ｔは、１．０〜４．０ｍｍである。また左右の電極全体は円柱状でおよそ８ｍｍの直径で、全体の長さは３０ｍｍ程度の大きさである。   In FIG. 5, an example of the electrode shape used for the joining of this invention is shown. The electrodes are arranged symmetrically with respect to the central insulating layer 15 and attached so as to slide up and down. The electrode interval L, which is the thickness of the insulating layer, is about 0.05 mm to 1.0 mm. Further, as shown in FIG. 5B, the shape of the contact surface 16 viewed from the lower end side of the electrode is also the left and right object with the insulating layer 15 interposed therebetween. The contact surface 16 at the lower end of the electrode is finished smoothly. The lower end of the insulating layer 15 is set inside the lower end of the electrode, and the distance H is 0.5 to 5.0 mm. The width T of the end portion of the electrode is 1.0 to 4.0 mm. The entire left and right electrodes are cylindrical and have a diameter of about 8 mm, and the overall length is about 30 mm.

以上、ターミナルとリードワイヤを接合する場合を例に本発明の実施の形態を説明したが、接合される部材や部材の材料はその例に限定されるものではない。本発明は、少なくとも一方が通電により発熱する金属材料でできた部材であればよい。
以上説明した実施の形態は本発明の一例であって、本発明は、特許請求の範囲の請求項に記載される事項によってのみ規定されており、上記以外の実施の形態も実施可能である。 As mentioned above, although embodiment of this invention was described taking the case where a terminal and a lead wire are joined as an example, the member and material of a member to be joined are not limited to the example. The present invention only needs to be a member made of a metal material that generates heat when energized.
The embodiment described above is an example of the present invention, and the present invention is defined only by matters described in the claims of the claims, and other embodiments can be implemented.

本発明の接合方法を説明するための図である。It is a figure for demonstrating the joining method of this invention. 本発明の接合方法の別の態様を説明するための図である。It is a figure for demonstrating another aspect of the joining method of this invention. 本発明の接合方法のさらに別の態様を説明するための図である。It is a figure for demonstrating another aspect of the joining method of this invention. 本発明を実施するための装置の概略図である。1 is a schematic view of an apparatus for carrying out the present invention. 本発明で用いる電極の一例を説明する図である。It is a figure explaining an example of the electrode used by this invention. 従来のパラレルギャップ溶接方法を説明するための図である。It is a figure for demonstrating the conventional parallel gap welding method.

符号の説明Explanation of symbols

１ａ、１ｂ 接合用の電極
２ リードワイヤ（接合しようとする部材）
３ 基板上に配置されたターミナル（接合しようとする部材）
４ 基板
６ メッキ層
７ メッキ層の溶融部
８ 冷却部材
９ 補助電極
１０ 電源
１１ 接合ヘッド
１２ａ、１２ｂ 電極ホルダ
１３ａ、１３ｂ 二次導体
１４ 信号線
１５ 絶縁層
１６ 電極の下端面 1a, 1b Electrode for joining 2 Lead wire (member to be joined)
3 Terminals placed on the board (members to be joined)
4 Substrate 6 Plating layer 7 Melting part of plating layer 8 Cooling member 9 Auxiliary electrode 10 Power source 11 Joining head 12a, 12b Electrode holder 13a, 13b Secondary conductor 14 Signal line 15 Insulating layer 16 Lower end surface of electrode

Claims (6)

接合しようとする２つの部材の少なくとも一方の部材の表面に、あらかじめ該部材の材料の融点よりも低い融点を有する金属材料のメッキ層を形成し、該２つの部材をメッキ層を間に介在させて重ね合わせ、所定の間隔を置いて平行にセットされた２本の電極を該部材に押し当て、電極間に通電して部材の抵抗発熱により前記メッキ層を溶融させて２つの部材を接合することを特徴とする接合方法。   A plating layer of a metal material having a melting point lower than the melting point of the material of the member is formed in advance on the surface of at least one of the two members to be joined, and the two members are interposed between the plating layers. Two electrodes set in parallel with a predetermined interval are pressed against the member, and the plated layer is melted by resistance heating of the member by energizing between the electrodes to join the two members The joining method characterized by the above-mentioned. 前記２つの部材の材質が異なっており、導電性の高い方の部材に前記メッキ層を形成して、その部材を電極側に配置したことを特徴とする請求項２に記載の接合方法。   3. The joining method according to claim 2, wherein the two members are made of different materials, the plating layer is formed on a member having higher conductivity, and the member is disposed on the electrode side. 接合しようとする一方の部材が銅または銅合金よりなり、該部材の表面に銀または銀合金よりなるメッキ層が形成されていることを特徴とする請求項１または２に記載の接合方法。   The joining method according to claim 1 or 2, wherein one member to be joined is made of copper or a copper alloy, and a plating layer made of silver or a silver alloy is formed on the surface of the member. メッキ層を前記２つの部材のそれぞれの表面に形成することを特徴とする請求項１〜３に記載の接合方法。   The bonding method according to claim 1, wherein a plating layer is formed on each surface of the two members. 前記電極間に冷却部材を配置し、冷却部材に接する部材の温度を低下させて、それぞれの電極と冷却部材の間でメッキ層を溶融させることを特徴とする請求項１〜４のいずれか１項に記載の接合方法。   The cooling member is disposed between the electrodes, the temperature of the member in contact with the cooling member is lowered, and the plating layer is melted between each electrode and the cooling member. The joining method according to item. 前記電極間に補助電極を配置し、補助電極からそれぞれの電極に向けて電流を供給して、それぞれの電極と補助電極の間で前記メッキ層を溶融させることを特徴とする請求項１〜４のいずれか１項に記載の接合方法。   The auxiliary electrode is disposed between the electrodes, current is supplied from the auxiliary electrode to each electrode, and the plating layer is melted between each electrode and the auxiliary electrode. The joining method according to any one of the above.

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