JPH1133747A - Junction of copper pipe and aluminum pipe and method thereof - Google Patents
Junction of copper pipe and aluminum pipe and method thereofInfo
- Publication number
- JPH1133747A JPH1133747A JP9205256A JP20525697A JPH1133747A JP H1133747 A JPH1133747 A JP H1133747A JP 9205256 A JP9205256 A JP 9205256A JP 20525697 A JP20525697 A JP 20525697A JP H1133747 A JPH1133747 A JP H1133747A
- Authority
- JP
- Japan
- Prior art keywords
- tube
- aluminum
- copper
- copper tube
- tapered portion
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Non-Disconnectible Joints And Screw-Threaded Joints (AREA)
- Arc Welding In General (AREA)
- Pressure Welding/Diffusion-Bonding (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、良好な気密性及び
接合強度を有する銅管とアルミニウム管との接合体及び
接合方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joined body and a joining method of a copper tube and an aluminum tube having good airtightness and joint strength.
【０００２】[0002]
【従来の技術及び発明が解決しようとする課題】冷蔵庫
や空調機器等に使用されている熱交換器においては、圧
縮機やキャピラリー管等用の銅管と蒸発器や凝縮機等用
のアルミニウム管とが使用されており、これらの管は種
々の方法により接合されている。従来から知られている
接合方法としては、圧接法（フリクションウェルディン
グ法）、融接法（フラッシュバットウェルディング法、
超音波亜鉛ソルダリング法）、拡散接合法等が挙げられ
る。2. Description of the Related Art In heat exchangers used in refrigerators and air conditioners, copper tubes for compressors and capillary tubes and aluminum tubes for evaporators and condensers are known. And these tubes are joined in various ways. Conventionally known bonding methods include a pressure welding method (friction welding method), a fusion welding method (flash butt welding method,
Ultrasonic zinc soldering method), diffusion bonding method and the like.
【０００３】このような用途では銅管とアルミニウム管
との接合部に高い気密性及び接合強度だけでなく、機械
的変形に対する気密性の保持力が高いことも要求される
が、従来の接合方法では上記要求を十分に満たすことが
できない。例えば融接法の場合、接合部に脆弱相の形成
が避けられないので、機械的変形に対する気密性の保持
力が十分でない。また圧接法では接合時の加圧力に耐え
るだけの管厚が必要であり、また突き合わせ接合部が脆
弱であるという問題がある。さらに圧接法では瞬間的な
加熱溶融及び加圧力の適正な管理が困難であるので、接
合品質の安定化及びコスト削減に限界がある。[0003] In such applications, not only the joint between the copper tube and the aluminum tube is required to have not only high hermeticity and joint strength but also a high force of maintaining hermeticity against mechanical deformation. Then, the above requirements cannot be sufficiently satisfied. For example, in the case of the fusion welding method, the formation of a fragile phase at the joint is inevitable, so that the force for maintaining the hermeticity against mechanical deformation is not sufficient. In the pressure welding method, there is a problem that the pipe thickness is required to withstand the pressing force at the time of joining, and that the butt joint is weak. Further, it is difficult to appropriately control the instantaneous heating and melting and the pressing force by the pressure welding method, so that there is a limit in stabilizing the joining quality and reducing the cost.
【０００４】このような接合方法の中で拡散接合法は強
固な接合部が形成できるので有望であり、種々の方法が
提案されている。例えば特公昭62-55477号は、アルミニ
ウム部材の端面に断面Ｖ字状の環状溝を形成するととも
に、アルミニウム管の先端部を前記環状溝と相補的な断
面形状とし、アルミニウム管の環状溝に銅部材の先端部
を当接した状態で、接触面をアルミニウム／銅の共晶温
度以上でアルミニウムの融点以下の温度に高周波加熱
し、共晶反応により接触面に生じた融液相を両部材の相
互押圧により外部に排出し、その後直ちに急冷すること
を特徴とするアルミニウム管と銅管との接合方法を開示
している。しかしながら、この接合方法では、アルミニ
ウム管の端面に形成した環状溝内に銅管の先端部を当接
した状態で接合するので、接合部分の面積が不十分であ
り、得られる接合体に十分な気密性及び機械的接合強度
を確保するのが難しいという問題がある。Among such bonding methods, the diffusion bonding method is promising because a strong bonding portion can be formed, and various methods have been proposed. For example, Japanese Patent Publication No. Sho 62-55477 discloses that an annular groove having a V-shaped cross section is formed on an end surface of an aluminum member, and a distal end portion of an aluminum tube has a sectional shape complementary to the annular groove. With the tip of the member in contact, the contact surface is high-frequency heated to a temperature equal to or higher than the eutectic temperature of aluminum / copper and equal to or lower than the melting point of aluminum. Disclosed is a method for joining an aluminum pipe and a copper pipe, wherein the pipes are discharged to the outside by mutual pressing and then immediately cooled. However, in this joining method, since the joining is performed in a state where the tip of the copper tube is in contact with the annular groove formed in the end face of the aluminum tube, the area of the joining portion is insufficient, and the joining body obtained is insufficient. There is a problem that it is difficult to ensure airtightness and mechanical bonding strength.
【０００５】また特開平8-19876 号は、アルミニウム管
を固定するステンレス製チャック部と、それと一体のス
テンレス製拡管拘束部を有する可動クランプ装置を使用
し、クランプ装置に固定したアルミニウム管の端部に加
熱した銅管のテーパ状端部を圧入することにより、両管
を接合する方法を開示している。可動クランプ装置の拡
管拘束部は移動しながら外嵌合管の拡がりを防止するの
みならず、重ね接合部における外嵌合管を圧下して接触
面での密接度合いを強め、均等な共晶合金層の形成を促
し、過剰な共晶合金を排除している。しかしながら拡管
拘束部の内面は等径でテーパ部がなく、また接合部上を
移動するようになっているので、銅管とアルミニウム管
との間に非常に薄い共晶相を均一に形成することはでき
ない。Japanese Patent Application Laid-Open No. Hei 8-19876 discloses an end portion of an aluminum tube fixed to a clamp device using a stainless steel chuck portion for fixing an aluminum tube and a movable clamp device having a stainless steel expansion restricting portion integrated therewith. Discloses a method of joining both tubes by press-fitting a tapered end of a heated copper tube. The pipe expansion restraint part of the movable clamp device not only prevents the expansion of the outer fitting pipe while moving, but also lowers the outer fitting pipe at the lap joint to increase the degree of close contact at the contact surface, and achieve a uniform eutectic alloy It promotes layer formation and eliminates excess eutectic alloy. However, since the inner surface of the expansion constrained part has the same diameter and no taper, and moves on the joint, a very thin eutectic phase must be uniformly formed between the copper tube and the aluminum tube. Can not.
【０００６】特開平9-85467 号は、銅管とアルミニウム
管との接合方法において、(a) 前記銅管の端部に長手方
向の少なくとも一部が凸曲面状のテーパ部を形成し、そ
の際凸曲面部の長手方向接線が前記銅管の長手方向接線
となす角度を銅管先端部方向に単調増加とし、(b) 前記
銅管のテーパ部を銅／アルミニウムの共晶温度以上でア
ルミニウムの融点未満の温度に加熱し、(c) 前記銅管の
テーパ部に、前記銅管の外径より小さい内径を有するア
ルミニウム管を外嵌めして、前記銅管の凸曲面部に前記
アルミニウム管の内面を加圧下で摺接させ、もって銅と
アルミニウムとの界面に相互拡散による共晶相を過渡的
に形成させ、(d) 脆い共晶相の成長を少なくするため
に、得られた接合部を急冷することを特徴とする接合方
法を開示している。銅管の端部に長手方向の少なくとも
一部が凸曲面状のテーパ部を有するので、銅管とアルミ
ニウム管との接合面は大きく、また両者の界面に形成さ
れた共晶相は薄くかつ均一であるという利点を有する。Japanese Patent Application Laid-Open No. 9-85467 discloses a method of joining a copper tube and an aluminum tube, wherein (a) forming a tapered portion having a convex curved surface at least in a longitudinal direction at an end of the copper tube; The angle between the longitudinal tangent of the convex portion and the longitudinal tangent of the copper tube is monotonically increased in the direction of the tip of the copper tube, and (b) the taper portion of the copper tube is made of aluminum at a temperature higher than the eutectic temperature of copper / aluminum. (C) an aluminum tube having an inner diameter smaller than the outer diameter of the copper tube is externally fitted to the tapered portion of the copper tube, and the aluminum tube is fitted to the convex curved surface portion of the copper tube. (D) to form a eutectic phase by interdiffusion transiently at the interface between copper and aluminum, and to reduce the growth of the brittle eutectic phase. A joining method characterized by quenching a part is disclosed. At least a part of the copper pipe at the end has a convex tapered portion at least in the longitudinal direction, so that the joining surface between the copper pipe and the aluminum pipe is large, and the eutectic phase formed at the interface between the two is thin and uniform. It has the advantage of being
【０００７】ところが冷蔵庫や空調機器等では、接合体
の気密性及び接合強度をいっそう向上させるとともに機
械的変形に対しても十分な気密性保持力を有するように
するという厳しい要件が要求されるが、かかる要求に完
全に答えるためには接合界面での共晶相を10μｍ以下と
非常に薄くすることが必要であることが分かった。しか
しながらアルミニウム管の接合部は拘束されていないの
で、接合界面での共晶相を10μｍ以下と均一に薄くする
ことはできない。However, refrigerators, air conditioners, and the like are required to have strict requirements to further improve the airtightness and bonding strength of the bonded body and to have a sufficient airtightness retaining force against mechanical deformation. It has been found that it is necessary to make the eutectic phase at the joining interface as thin as 10 μm or less in order to completely meet such requirements. However, since the joining portion of the aluminum tube is not restricted, the eutectic phase at the joining interface cannot be uniformly thinned to 10 μm or less.
【０００８】従って本発明の目的は、大きな接合面積を
有するとともに気密性及び接合強度の信頼性が高く、か
つ機械的変形に対しても十分な気密性保持力を有する銅
管とアルミニウム管との接合体を提供することである。Accordingly, an object of the present invention is to provide a copper pipe and an aluminum pipe which have a large joint area, high airtightness and high reliability of joint strength, and have sufficient airtightness retaining force against mechanical deformation. It is to provide a conjugate.
【０００９】本発明のもう１つの目的は、かかる特徴を
有する接合体を得るために、銅管とアルミニウム管とを
安価にかつ効率良く接合する方法を提供することであ
る。Another object of the present invention is to provide a method of joining a copper tube and an aluminum tube at low cost and efficiently in order to obtain a joined body having such characteristics.
【００１０】[0010]
【課題を解決するための手段】上記目的に鑑み鋭意研究
の結果、本発明者等は、内嵌用銅管の端部にテーパ部を
設け、かつアルミニウム管の先端部を拘束するようにク
ランプで固定し、加熱した銅管のテーパ部をクランプで
拘束したアルミニウム管に圧入することにより、銅管と
アルミニウム管との界面に銅／アルミニウムの共晶相を
形成する場合に、クランプ内面の先端付近に銅管のテー
パ部とほぼ同じ傾斜のテーパ部を設けておくことによ
り、形成される共晶相を非常に薄くすることができるこ
とを発見し、本発明に想到した。As a result of intensive studies in view of the above-mentioned objects, the present inventors have found that a tapered portion is provided at an end of a copper pipe for internal fitting, and a clamp is provided so as to restrain the tip of an aluminum pipe. When a copper / aluminum eutectic phase is formed at the interface between the copper tube and the aluminum tube by press-fitting the tapered portion of the heated copper tube into the aluminum tube constrained by the clamp, the tip of the inner surface of the clamp is fixed. It has been discovered that the eutectic phase to be formed can be made extremely thin by providing a tapered portion having substantially the same inclination as the tapered portion of the copper tube in the vicinity, and reached the present invention.
【００１１】すなわち、本発明の銅管とアルミニウム管
との接合体は、銅管の端部に形成されたテーパ部が前記
銅管の外径より小さい内径を有するアルミニウム管に圧
入されてなるもので、前記銅管の外面と前記アルミニウ
ム管の内面との界面に前記テーパ部の半分以上の長さに
わたって銅とアルミニウムとの共晶相が形成されてお
り、かつ前記共晶相のうち厚さ10μｍ以下の領域の長さ
が１mm以上であることを特徴とする。That is, a joined body of a copper tube and an aluminum tube according to the present invention is obtained by press-fitting a tapered portion formed at an end of the copper tube into an aluminum tube having an inner diameter smaller than the outer diameter of the copper tube. A eutectic phase of copper and aluminum is formed at an interface between an outer surface of the copper tube and an inner surface of the aluminum tube over a length of at least half of the tapered portion, and the thickness of the eutectic phase is The length of the region of 10 μm or less is 1 mm or more.
【００１２】また本発明の銅管とアルミニウム管との接
合方法は、(a) 前記アルミニウム管の内径より僅かに大
きい外径を有する前記銅管の端部にテーパ部を形成し、
(b)前記アルミニウム管の外径と実質的に同一の内径を
有するとともに、先端付近の内面に前記銅管のテーパ部
とほぼ同じ傾斜のテーパ部が設けられているクランプに
より、前記アルミニウム管の先端部を把持・固定し、
(c) 前記銅管のテーパ部を、銅／アルミニウムの共晶温
度以上でアルミニウムの融点未満の温度に加熱し、(d)
前記銅管のテーパ部を前記クランプで固定した前記アル
ミニウム管の先端部内に圧入し、もって前記銅管の外面
と前記アルミニウム管の内面との界面に銅／アルミニウ
ムの共晶相を形成させることにより、両者を密封状態に
接合することを特徴とする。[0012] The method for joining a copper tube and an aluminum tube according to the present invention comprises: (a) forming a tapered portion at an end of the copper tube having an outer diameter slightly larger than the inner diameter of the aluminum tube;
(b) a clamp having substantially the same inner diameter as the outer diameter of the aluminum tube, and having a taper portion having the same inclination as the taper portion of the copper tube provided on the inner surface near the tip, Hold and fix the tip,
(c) heating the tapered portion of the copper tube to a temperature equal to or higher than the eutectic temperature of copper / aluminum and lower than the melting point of aluminum;
By press-fitting the tapered portion of the copper tube into the tip of the aluminum tube fixed by the clamp, thereby forming a eutectic phase of copper / aluminum at the interface between the outer surface of the copper tube and the inner surface of the aluminum tube. It is characterized in that both are joined in a sealed state.
【００１３】本発明の接合方法によれば、銅管の外面と
アルミニウム管の内面との界面に形成される共晶相は広
い面積を有するだけでなく、厚さ10μｍ以下の領域の長
さが１mm以上もあり、接合部の気密性及び接合強度が十
分であるのみならず、機械的変形に対しても十分な気密
性保持力を有する。According to the joining method of the present invention, the eutectic phase formed at the interface between the outer surface of the copper tube and the inner surface of the aluminum tube has not only a large area but also a region having a thickness of 10 μm or less. It is not less than 1 mm, and has not only a sufficient hermeticity and a joint strength of the joint portion but also a sufficient hermeticity retaining force against mechanical deformation.
【００１４】[0014]
【発明の実施の形態】本発明を図面を参照しながら以下
詳細に説明するが、本発明はそれらに限定されるもので
はない。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings, but the present invention is not limited thereto.
【００１５】[1] 銅管及びアルミニウム管 (1) 銅管 銅管１は端部にテーパ部11が形成されている。テーパ部
11の長さは銅管１の外径の１〜３倍であるのが好まし
い。テーパ部11が銅管１の外径より短いと共晶相の形成
により得られる接合面積が不十分である。またテーパ部
11の長さが銅管１の外径の３倍を超えると、テーパ部11
の傾斜が緩やか過ぎて、アルミニウム管２への圧入が困
難になる。例えば銅管１の外径が７〜９mm（特に８mm）
の場合、テーパ部11は10〜20mm（特に約15mm）であるの
が好ましい。[1] Copper Tube and Aluminum Tube (1) Copper Tube The copper tube 1 has a tapered portion 11 formed at an end. Tapered part
The length of 11 is preferably 1 to 3 times the outer diameter of the copper tube 1. If the tapered portion 11 is shorter than the outer diameter of the copper tube 1, the joining area obtained by forming the eutectic phase is insufficient. Also taper
If the length of 11 exceeds three times the outer diameter of copper tube 1, taper 11
Is too gentle, and it is difficult to press-fit into the aluminum tube 2. For example, the outer diameter of the copper tube 1 is 7 to 9 mm (especially 8 mm)
In this case, the tapered portion 11 is preferably 10 to 20 mm (particularly about 15 mm).
【００１６】図１に示す本発明の第一の実施例では、銅
管１のテーパ部11の傾斜は直線的である。銅管１の長手
方向に対するテーパ部11の傾斜角αは１〜８°であるの
が好ましい。傾斜角αがこの範囲内にあると、両管の圧
接力が適度であり、銅管１の外面とアルミニウム管２の
内面とがぴったりと密着するために、均一な薄い共晶相
が形成される。より好ましい傾斜角αは約２〜６°であ
り、特に３〜５°である。In the first embodiment of the present invention shown in FIG. 1, the inclination of the tapered portion 11 of the copper tube 1 is linear. The inclination angle α of the tapered portion 11 with respect to the longitudinal direction of the copper tube 1 is preferably 1 to 8 °. When the inclination angle α is within this range, the pressure contact force between the two tubes is appropriate, and the outer surface of the copper tube 1 and the inner surface of the aluminum tube 2 are in close contact with each other, so that a uniform thin eutectic phase is formed. You. A more preferable inclination angle α is about 2 to 6 °, particularly 3 to 5 °.
【００１７】図２に示す本発明の第二の実施例では、銅
管１のテーパ部11に凸曲面部11ａを設ける。また先端部
に曲面状の縮径部11ｂを設けてもよい。凸曲面部11ａの
曲率半径Ｒは、アルミニウム管２の先端部に銅管１のテ
ーパ部11を圧入する際に、アルミニウム管２の先端部が
拡径しながら銅管１のテーパ部11の外面に大きな圧力で
摺接するように、設定するのが好ましい。このために
は、例えば銅管１の外径が６〜10mm（特に８mm）の場
合、曲率半径Ｒは240 〜640 mmであるのが好ましい。凸
曲面部11ａは全域にわたって同一の曲率半径を有する必
要はないが、その曲率半径Ｒが全域にわたって同一の場
合に大きな圧接力が生じ、凸曲面部11ａ全体に薄い共晶
相が得られる。In the second embodiment of the present invention shown in FIG. 2, a tapered portion 11 of a copper tube 1 is provided with a convex curved surface portion 11a. Further, a curved reduced diameter portion 11b may be provided at the tip end. The radius of curvature R of the convex curved surface portion 11a is such that when the tapered portion 11 of the copper tube 1 is press-fitted into the tip portion of the aluminum tube 2, the outer surface of the tapered portion 11 of the copper tube 1 is expanded while the tip portion of the aluminum tube 2 is enlarged. It is preferable to set so as to be in sliding contact with a large pressure. For this purpose, for example, when the outer diameter of the copper tube 1 is 6 to 10 mm (especially 8 mm), the radius of curvature R is preferably 240 to 640 mm. The convex curved surface portion 11a does not need to have the same radius of curvature over the entire region, but when the radius of curvature R is the same over the entire region, a large pressing force is generated, and a thin eutectic phase is obtained over the entire convex curved surface portion 11a.
【００１８】図３は図２の銅管１のテーパ部11の傾斜を
示す概略図である。明瞭化のために図３ではテーパ部11
の傾斜角は誇張されている。まず銅管１の長手方向接線
に対する凸曲面部11ａの平均傾斜角α' は１〜８°であ
る。平均傾斜角α' がこの範囲内にあると、両管の圧接
力が適度であり、銅管１の外面とアルミニウム管２の内
面とがぴったりと密着するために、均一な薄い共晶相が
形成される。より好ましい平均傾斜角α' は約１〜３°
である。凸曲面部11ａの膨らみ（テーパ部11の表面とテ
ーパ部11の両端を結ぶ直線との最大距離）ｄは0.05〜0.
15mmであるのが好ましい。例えば銅管１の外径が６〜10
mm（特に８mm）の場合、膨らみｄは0.1mm程度であるの
が好ましい。FIG. 3 is a schematic view showing the inclination of the tapered portion 11 of the copper tube 1 of FIG. For clarity, FIG.
The angle of inclination is exaggerated. First, the average inclination angle α 'of the convex curved surface portion 11a with respect to the longitudinal tangent of the copper tube 1 is 1 to 8 °. When the average inclination angle α ′ is within this range, the pressure contact force between the two tubes is appropriate, and the outer surface of the copper tube 1 and the inner surface of the aluminum tube 2 are in close contact with each other, so that a uniform thin eutectic phase is formed. It is formed. More preferable average inclination angle α ′ is about 1 to 3 °
It is. The bulge (maximum distance between the surface of the tapered portion 11 and a straight line connecting both ends of the tapered portion 11) d of the convex curved surface portion 11a is 0.05 to 0.
It is preferably 15 mm. For example, the outer diameter of the copper tube 1 is 6 to 10
In the case of mm (especially 8 mm), the bulge d is preferably about 0.1 mm.
【００１９】テーパ部11の先端部に設けられた縮径部11
ｂは、銅管１がアルミニウム管２にスムーズに挿入でき
るようにするとともに、アルミニウム管２の内面が最初
に強く圧接される部分であり、縮径部11ｂでアルミニウ
ム管２は拡径される。縮径部11ｂは0.5 〜２mmの長さ及
び20〜45°の平均傾斜角β（銅管１の長手方向接線に対
する）を有するのが好ましい。例えば銅管１の外径が６
〜10mm（特に８mm）の場合、縮径部11ｂは１mm程度の長
さ及び30°の平均傾斜角βを有するのが好ましい。The reduced diameter portion 11 provided at the tip of the tapered portion 11
b is a portion where the copper tube 1 can be smoothly inserted into the aluminum tube 2 and the inner surface of the aluminum tube 2 is first strongly pressed against the inside, and the diameter of the aluminum tube 2 is expanded at the reduced diameter portion 11b. The reduced diameter portion 11b preferably has a length of 0.5 to 2 mm and an average inclination angle β (with respect to the longitudinal tangent of the copper tube 1) of 20 to 45 °. For example, when the outer diameter of the copper tube 1 is 6
In the case of about 10 mm (especially 8 mm), the reduced diameter portion 11b preferably has a length of about 1 mm and an average inclination angle β of 30 °.
【００２０】凸曲面部11ａ及び縮径部11ｂのために、銅
管１の先端部における外径Ｄ2 は銅管１の本体の外径Ｄ
1 の0.1 倍以上縮径している。縮径比［（Ｄ1 −Ｄ2 ）
／Ｄ1 ］が0.1 以上であると、アルミニウム管２への銅
管１の圧入が極めて容易になる。また縮径比が0.3 を超
えると銅管１の先端部の内径が小さすぎて、管内の流体
抵抗が大きくなる。従って、好ましい縮径比は0.1 〜0.
3 である。例えば銅管１の外径が６〜10mm（特に８mm）
の場合、縮径の程度は１mm以上が好ましく、特に1.3 mm
以上が好ましい。Because of the convex curved surface portion 11a and the reduced diameter portion 11b, the outer diameter D 2 at the tip of the copper tube 1 is equal to the outer diameter D of the main body of the copper tube 1.
The diameter is reduced 0.1 times or more than 1 . Diameter reduction ratio [(D 1 -D 2 )
/ D 1 ] is 0.1 or more, it becomes extremely easy to press-fit the copper tube 1 into the aluminum tube 2. If the diameter reduction ratio exceeds 0.3, the inner diameter of the tip of the copper tube 1 is too small, and the fluid resistance in the tube increases. Therefore, the preferred diameter reduction ratio is 0.1 to 0.
3 For example, the outer diameter of the copper tube 1 is 6 to 10 mm (especially 8 mm)
In the case of, the degree of diameter reduction is preferably 1 mm or more, particularly 1.3 mm
The above is preferred.
【００２１】図４は本発明の第三の実施例による銅管の
テーパ部を示す縦断面図である。この実施例では、テー
パ部12は１つの凸曲面部12ａと、凸曲面部12ａより先端
側のほぼ平坦なテーパ部分12ｂと、凸曲面部12ａより本
体側のほぼ平坦なテーパ部分12ｃとからなる。ほぼ平坦
なテーパ部分12ａ及び12ｃの接線は凸曲面部12ａの接線
と整合している。すなわち傾斜角が不連続に変化する部
分がない。好ましい実施例では、凸曲面部12ａは銅管１
の外径の0.3 〜１倍の長さ及び10〜60mmの曲率半径を有
するのが好ましい。またほぼ平坦なテーパ部分12ｂは銅
管１の外径の0.3 〜１倍の長さを有するのが好ましい。
さらにほぼ平坦なテーパ部分12ｃは銅管１の外径の0.3
〜１倍の長さ及び0.5 〜1.5 °の平均傾斜角δを有する
のが好ましい。長さに関しては、例えば銅管１の外径が
６〜10mm（特に８mm）の場合、凸曲面部12ａは３〜８m
m、好ましくは４〜６mm（特に５mm）であり、テーパ部
分12ｂは３〜８mm、好ましくは４〜６mm（特に５mm）で
あり、テーパ部分12ｃは３〜８mm、好ましくは４〜６mm
（特に５mm）である。FIG. 4 is a longitudinal sectional view showing a tapered portion of a copper tube according to a third embodiment of the present invention. In this embodiment, the tapered portion 12 is composed of one convex curved surface portion 12a, a substantially flat tapered portion 12b on the distal end side from the convex curved surface portion 12a, and a substantially flat tapered portion 12c on the main body side from the convex curved surface portion 12a. . The tangents of the substantially flat tapered portions 12a and 12c are aligned with the tangents of the convex curved surface 12a. That is, there is no portion where the inclination angle changes discontinuously. In the preferred embodiment, the convex curved portion 12a is a copper tube 1
It preferably has a length of 0.3 to 1 times the outer diameter of and a radius of curvature of 10 to 60 mm. The substantially flat tapered portion 12b preferably has a length of 0.3 to 1 times the outer diameter of the copper tube 1.
Further, the substantially flat tapered portion 12c is 0.3 mm of the outer diameter of the copper tube 1.
It preferably has a length of .about.1 times and an average inclination angle .delta. Of 0.5-1.5 DEG. Regarding the length, for example, when the outer diameter of the copper tube 1 is 6 to 10 mm (especially 8 mm), the convex curved surface portion 12a is 3 to 8 m
m, preferably 4-6 mm (especially 5 mm), the tapered portion 12b is 3-8 mm, preferably 4-6 mm (especially 5 mm), and the tapered portion 12c is 3-8 mm, preferably 4-6 mm.
(Especially 5 mm).
【００２２】なお第二実施例と同様に、第三実施例の銅
管１のテーパ部12の先端部に縮径部を設けてもよい。ま
たテーパ部分12ｃを平坦（直線状）とする代わりに、曲
率半径の小さな凸曲面状としてもよい。この場合、テー
パ部分12ｃの曲率半径は第二実施例の曲率半径（240 〜
640 mm）と同じでよい。As in the second embodiment, a reduced diameter portion may be provided at the tip of the tapered portion 12 of the copper tube 1 of the third embodiment. Further, instead of making the tapered portion 12c flat (linear), it may be formed into a convex curved surface having a small radius of curvature. In this case, the radius of curvature of the tapered portion 12c is the radius of curvature of the second embodiment (240 to 240).
640 mm).
【００２３】(2) アルミニウム管 アルミニウム管２は、銅管１との気密な接合を達成する
ために、銅管１の外径より僅かに小さな内径を有するの
が好ましい。理論的にはアルミニウム管２の内径は銅管
１の外径と同じで良いが、製造誤差を考慮してアルミニ
ウム管２の内径を僅かに小さくする。しかし、アルミニ
ウム管２の内径が小さすぎると圧入が困難になるので、
銅管の外径／アルミニウム管の内径の上限は1.5 とする
のが好ましい。(2) Aluminum Tube The aluminum tube 2 preferably has an inner diameter slightly smaller than the outer diameter of the copper tube 1 in order to achieve an airtight connection with the copper tube 1. Theoretically, the inner diameter of the aluminum tube 2 may be the same as the outer diameter of the copper tube 1, but the inner diameter of the aluminum tube 2 is slightly reduced in consideration of manufacturing errors. However, if the inner diameter of the aluminum tube 2 is too small, press-fitting becomes difficult.
The upper limit of the outer diameter of the copper tube / the inner diameter of the aluminum tube is preferably 1.5.
【００２４】[2] 接合装置 図１は本発明の好ましい一実施例による銅管１とアルミ
ニウム管２との接合装置を示す。[2] Joining Apparatus FIG. 1 shows an apparatus for joining a copper tube 1 and an aluminum tube 2 according to a preferred embodiment of the present invention.
【００２５】接合装置は、銅管１のテーパ部11の周囲に
設けられた高周波加熱コイル４と、アルミニウム管２の
先端部を保持するクランプ５と、高周波加熱コイル４の
近傍に設けられた窒素ガス吹き付け管６と、銅管１の後
端部を把持・固定する２つ割りのクランプ（図示せず）
とを有する。The joining device includes a high-frequency heating coil 4 provided around the tapered portion 11 of the copper tube 1, a clamp 5 for holding the tip of the aluminum tube 2, and a nitrogen gas provided near the high-frequency heating coil 4. Gas blow pipe 6 and two separate clamps (not shown) for holding and fixing the rear end of copper pipe 1
And
【００２６】(1) アルミニウム管用クランプ 図１に示すように、クランプ５は２つ割りのクランプ片
５ａ、５ｂからなり、各クランプ片５ａ、５ｂの内面７
は、先端同径部７ａと、銅管１の圧入によるアルミニウ
ム管２の拡径を拘束するための中間のテーパ部７ｂと、
アルミニウム管２を把持・固定するための後端同径部７
ｃとからなる。先端同径部７ａの内径は銅管１の外径よ
り僅かに大きければ良いが、実用上は銅管１の外径にア
ルミニウム管２の肉厚の２倍を加えた径とほぼ等しいの
が好ましい。テーパ部７ｂの傾斜は銅管１のテーパ部11
の傾斜と実質的に同じであるのが好ましい。また後端同
径部７ｃの内径はアルミニウム管２の外径と実質的に同
じであるのが好ましい。(1) Clamp for Aluminum Tube As shown in FIG. 1, the clamp 5 comprises two clamp pieces 5a and 5b, and the inner surface 7 of each clamp piece 5a and 5b.
Has a tapered portion 7a at the tip and an intermediate tapered portion 7b for restraining the expansion of the aluminum tube 2 by press fitting of the copper tube 1;
Rear end same diameter part 7 for holding and fixing aluminum tube 2
c. The inner diameter of the tip-end same-diameter portion 7a may be slightly larger than the outer diameter of the copper tube 1, but in practice, it is approximately equal to the outer diameter of the copper tube 1 plus twice the thickness of the aluminum tube 2. preferable. The inclination of the tapered portion 7b is equal to the tapered portion 11 of the copper tube 1.
Is preferably substantially the same. Further, it is preferable that the inner diameter of the rear end same diameter portion 7c is substantially the same as the outer diameter of the aluminum tube 2.
【００２７】後端同径部７ｃの長さは、アルミニウム管
２を確実に把持・固定できる長さであれば特に限定され
ない。テーパ部７ｂの長さは銅管１の外径の0.2 倍〜1.
5 倍であるのが好ましく、0.5 〜１倍であるのがより好
ましい。なお先端同径部７ａの長さは特に限定されな
い。The length of the rear end same-diameter portion 7c is not particularly limited as long as the aluminum tube 2 can be securely gripped and fixed. The length of the tapered portion 7b is 0.2 to 1.times. The outer diameter of the copper tube 1.
It is preferably 5 times, more preferably 0.5 to 1 times. In addition, the length of the end same-diameter portion 7a is not particularly limited.
【００２８】クランプ５は良好な機械的強度、高耐熱性
及び低熱伝達率等を要するために、ステンレススティー
ル、高速度鋼、セラミックス等により形成するか、これ
らの素材を複合して形成するのが好ましい。Since the clamp 5 requires good mechanical strength, high heat resistance, low heat transfer coefficient, etc., it is necessary to form the clamp 5 from stainless steel, high-speed steel, ceramics, or the like, or to form a composite of these materials. preferable.
【００２９】(2) 高周波加熱コイル 高周波加熱コイル４は通常の２又は３ターンのコイルで
よいが、２つ割りのコイルにより形成しても良い。高周
波加熱コイル４の出力は約20ｋＷもあれば十分であり、
またその周波数は約100 ｋＨｚ近傍で良い。(2) High-frequency heating coil The high-frequency heating coil 4 may be a usual two- or three-turn coil, but may be formed by a two-piece coil. The output of the high-frequency heating coil 4 needs only about 20 kW,
Further, the frequency may be around 100 kHz.
【００３０】(3) 窒素ガス吹き付け管 高周波加熱コイル４の近傍に配置された窒素ガス吹き付
け管６は、図１及び図５に示すように、先端がＬ字型に
屈曲していおり、先端部６ａの底面には複数の通気孔６
ｂが一列に設けられている。管６の上端は窒素ガス供給
源（図示せず）に連結しており、管６に供給された窒素
ガスは複数の通気孔６ｂより下方に向けて噴出され、銅
管１の加熱されたテーパ部11を包囲する。これよにり銅
管１が加熱中に酸化するのを有効に防止することができ
る。(3) Nitrogen Gas Blowing Tube As shown in FIGS. 1 and 5, the nitrogen gas blowing tube 6 disposed near the high-frequency heating coil 4 has an L-shaped tip, A plurality of ventilation holes 6 are provided on the bottom of 6a.
b are provided in a line. The upper end of the pipe 6 is connected to a nitrogen gas supply source (not shown), and the nitrogen gas supplied to the pipe 6 is jetted downward from the plurality of vents 6b, and the heated taper of the copper pipe 1 is formed. Surrounds part 11. Accordingly, it is possible to effectively prevent the copper tube 1 from being oxidized during heating.
【００３１】(4) 銅管用クランプ 銅管１用クランプ（図示せず）も２つ割りのクランプ片
からなり、銅管１内に窒素ガスを流通し得るように構成
されている。これにより加熱中に銅管１の内面が酸化さ
れるのを防止することができる。また圧入直後に接合部
を急冷するために窒素ガス又は圧縮空気を利用すること
もできる。(4) Copper Tube Clamp The copper tube 1 clamp (not shown) is also composed of two clamp pieces, and is configured so that nitrogen gas can flow through the copper tube 1. This can prevent the inner surface of the copper tube 1 from being oxidized during heating. Nitrogen gas or compressed air can also be used to rapidly cool the joint immediately after press-fitting.
【００３２】[3] 接合方法 図１に示すように、銅管１をクランプ（図示せず）によ
り把持・固定するとともに、アルミニウム管２の先端部
を一対のクランプ片５ａ、５ｂの間に配置し、図６に示
すようクランプ片５ａ、５ｂを閉じる。このときアルミ
ニウム管２の先端部がクランプ片５ａ、５ｂの先端より
僅かに内側に位置するように、アルミニウム管２を位置
決めるのが好ましい。[3] Joining method As shown in FIG. 1, the copper tube 1 is gripped and fixed by a clamp (not shown), and the tip of the aluminum tube 2 is arranged between a pair of clamp pieces 5a and 5b. Then, the clamp pieces 5a and 5b are closed as shown in FIG. At this time, it is preferable to position the aluminum tube 2 so that the distal end of the aluminum tube 2 is located slightly inside the distal ends of the clamp pieces 5a and 5b.
【００３３】次に銅管１のテーパ部11の先端部をクラン
プ片５ａ、５ｂの先端同径部７ａ内に入れる。このとき
銅管１のテーパ部11の先端部の外径はアルミニウム管の
内径より小さいので、銅管１のテーパ部11の先端部はア
ルミニウム管２内に僅かに進入する。Next, the tip of the tapered portion 11 of the copper tube 1 is inserted into the same-diameter portion 7a of the tip of the clamp pieces 5a, 5b. At this time, since the outer diameter of the tip of the tapered portion 11 of the copper tube 1 is smaller than the inner diameter of the aluminum tube, the tip of the tapered portion 11 of the copper tube 1 slightly enters the aluminum tube 2.
【００３４】この状態で高周波加熱コイル４を閉じて通
電し、銅管１のテーパ部11を銅／アルミニウムの共晶温
度以上でかつアルミニウムの融点未満の温度に加熱す
る。加熱の間窒素ガス吹き付け管６より窒素ガスを吹き
付けて、銅管１のテーパ部11の周囲を窒素ガスで覆うと
ともに、銅管１内に窒素ガスを通すこともできる。なお
窒素ガスの代わりにアルゴンガス等の他の不活性ガスを
使用しても良い。In this state, the high-frequency heating coil 4 is closed and energized to heat the tapered portion 11 of the copper tube 1 to a temperature higher than the eutectic temperature of copper / aluminum and lower than the melting point of aluminum. During the heating, nitrogen gas can be blown from the nitrogen gas blowing tube 6 to cover the periphery of the tapered portion 11 of the copper tube 1 with nitrogen gas, and also to allow nitrogen gas to pass through the copper tube 1. Note that another inert gas such as an argon gas may be used instead of the nitrogen gas.
【００３５】銅管１のテーパ部11の温度が共晶温度未満
であると、銅管１のアルミニウム管２内への圧入によっ
ても界面に共晶相が形成されない。またアルミニウムの
融点以上であるとアルミニウム管が変形して接合が不可
能になる。具体的には、テーパ部11の加熱温度は600 〜
800 ℃が好ましい。なお高周波加熱コイル４への通電時
間は３〜10秒間でよい。If the temperature of the tapered portion 11 of the copper tube 1 is lower than the eutectic temperature, no eutectic phase is formed at the interface even when the copper tube 1 is pressed into the aluminum tube 2. If the melting point is higher than the melting point of aluminum, the aluminum tube is deformed and cannot be joined. Specifically, the heating temperature of the tapered portion 11 is 600 to
800 ° C. is preferred. The energizing time to the high-frequency heating coil 4 may be 3 to 10 seconds.
【００３６】銅管１のテーパ部11が前記温度に達した後
は、銅管１のテーパ部11が共晶温度以上に維持される限
り、高周波加熱コイル４への通電を停止しても、或いは
通電量を減少させてもよい。After the tapered portion 11 of the copper tube 1 has reached the above temperature, as long as the tapered portion 11 of the copper tube 1 is maintained at a temperature higher than the eutectic temperature, the energization of the high-frequency heating coil 4 is stopped. Alternatively, the amount of current may be reduced.
【００３７】銅管１のテーパ部11が上記温度範囲内にあ
る間に、銅管１をクランプ５方向に押圧し、銅管１のテ
ーパ部11をアルミニウム管２内に圧入する。銅管１の圧
入速度は10mm／秒以上とするのが好ましい。圧入速度が
10mm／秒未満であると、銅管の外面とアルミニウム管の
内面との界面に薄くて均一な共晶相が形成されにくい。
好ましい圧入速度は10〜200 mm／秒である。While the tapered portion 11 of the copper tube 1 is within the above temperature range, the copper tube 1 is pressed in the direction of the clamp 5, and the tapered portion 11 of the copper tube 1 is pressed into the aluminum tube 2. The press-fitting speed of the copper tube 1 is preferably set to 10 mm / sec or more. Pressing speed
If it is less than 10 mm / sec, it is difficult to form a thin and uniform eutectic phase at the interface between the outer surface of the copper tube and the inner surface of the aluminum tube.
The preferred indentation speed is between 10 and 200 mm / sec.
【００３８】加熱した銅管１のテーパ部11をアルミニウ
ム管２内に圧入すると、図７に示すように、銅管１のテ
ーパ部11はアルミニウム管２の内面に圧接される。両管
の接触面における温度は銅／アルミニウム共晶温度（54
8 ℃）より高いので、接触面において銅／アルミニウム
共晶相が形成する。テーパ部11が進入するにつれてアル
ミニウム管２は拡径し、両管の界面では圧接された銅と
アルミニウムとが次々と共晶相を形成していく。このと
きアルミニウム管２はクランプ５により拘束されている
ので、アルミニウム管２が拡開しすぎることはなく、銅
管１のテーパ部11との圧接力は非常に強固となる。この
状態では銅管１の外面とアルミニウム管２の内面との間
には極めて僅かしか空間がないので、界面に生成した銅
／アルミニウム共晶合金のうち過剰のものは銅管１の先
端及びアルミニウム管２の先端に排出される。その結
果、銅管１とアルミニウム管２との間の非常に狭い界面
には微量の共晶相しか存在せず、共晶相は非常に薄いも
のとなる。When the tapered portion 11 of the heated copper tube 1 is pressed into the aluminum tube 2, the tapered portion 11 of the copper tube 1 is pressed against the inner surface of the aluminum tube 2 as shown in FIG. The temperature at the contact surface of both tubes is the copper / aluminum eutectic temperature (54
8 ° C.), a copper / aluminum eutectic phase forms at the interface. As the tapered portion 11 enters, the diameter of the aluminum tube 2 increases, and at the interface between the two tubes, the pressed copper and aluminum successively form a eutectic phase. At this time, since the aluminum tube 2 is restrained by the clamp 5, the aluminum tube 2 does not expand too much, and the pressure contact force with the tapered portion 11 of the copper tube 1 becomes very strong. In this state, since there is very little space between the outer surface of the copper tube 1 and the inner surface of the aluminum tube 2, excess copper / aluminum eutectic alloy formed at the interface is removed at the tip of the copper tube 1 and the aluminum. It is discharged to the tip of the tube 2. As a result, only a small amount of the eutectic phase exists at the very narrow interface between the copper tube 1 and the aluminum tube 2, and the eutectic phase becomes very thin.
【００３９】圧入により共晶相が形成された後、接合部
を急冷するのが好ましい。急冷のためには、連結した銅
管１とアルミニウム管２の内部に窒素ガス又は圧縮空気
を流せばよい。急冷速度は100 ℃／秒以上とするのが好
ましい。急冷速度が100 ℃／秒未満であると、得られた
共晶相が冷却の過程で結晶が粗大化し、脆化してしま
う。好ましい急冷速度は200 ℃／秒以上である。After the eutectic phase is formed by press-fitting, it is preferable to rapidly cool the joint. For rapid cooling, nitrogen gas or compressed air may be flowed inside the connected copper tube 1 and aluminum tube 2. Preferably, the quenching rate is 100 ° C./sec or more. If the quenching rate is less than 100 ° C./second, the obtained eutectic phase becomes coarse and brittle during cooling. The preferred quenching rate is 200 ° C./sec or more.
【００４０】[4] 接合体 上記接合方法により得られる本発明の接合体は、テーパ
部11の約１／２以上にわたって共晶相が形成されてい
る。共晶相の形成領域がテーパ部11の約１／２未満であ
ると、接合部の気密性及び接合強度が十分でない。さら
に本発明の接合体は、形成された共晶相のうち厚さが10
μｍ以下の領域の長手方向長さが１mm以上であることを
特徴とする。共晶相の厚さが10μｍ以下であると、機械
的変形力（剪断力等）に対する抵抗力が大きく、気密性
の保持力が十分である。10μｍ以下の厚さの共晶相の長
さは２mm以上が好ましい。[4] Joint In the joined body of the present invention obtained by the above-described joining method, the eutectic phase is formed over about 1/2 or more of the tapered portion 11. If the region where the eutectic phase is formed is less than about 1/2 of the tapered portion 11, the airtightness and the bonding strength of the bonded portion are not sufficient. Further, the bonded body of the present invention has a thickness of 10% of the formed eutectic phase.
The length in the longitudinal direction of the region of μm or less is 1 mm or more. When the thickness of the eutectic phase is 10 μm or less, the resistance to mechanical deformation (such as shearing force) is large, and the force for maintaining airtightness is sufficient. The length of the eutectic phase having a thickness of 10 μm or less is preferably 2 mm or more.
【００４１】[0041]
【実施例】本発明を以下の実施例により詳細に説明する
が、本発明はこれらの実施例に限定されるものではな
い。The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.
【００４２】参考例１ 厚さ１mm及び幅１０mmの銅板及び厚さ１mm及び幅１０mm
のアルミニウム板の表面をそれぞれワイヤーブラシで磨
いた後で、両板を重ね合わせた。次いで図８に示す工具
を使用し、42％の圧縮率で冷間圧接し、それを300 ℃か
ら500 ℃まで50℃毎の各温度に加熱し、共晶相を成長さ
せた。接合した両板を両側から引っ張り、接合部が剪断
剥離する時の負荷（Ｎ）を測定した。また各接合板の接
合界面における共晶相の厚さ（μｍ）を測定した。剪断
剥離負荷（Ｎ）と共晶相の厚さ（μｍ）との関係を図９
に示す。 REFERENCE EXAMPLE 1 A copper plate having a thickness of 1 mm and a width of 10 mm and a thickness of 1 mm and a width of 10 mm
After polishing the surface of each aluminum plate with a wire brush, the two plates were overlaid. Next, using the tool shown in FIG. 8, cold welding was performed at a compression ratio of 42%, and the resultant was heated from 300 ° C. to 500 ° C. at each temperature of 50 ° C. to grow a eutectic phase. The two bonded plates were pulled from both sides, and the load (N) when the bonded portion was sheared off was measured. Further, the thickness (μm) of the eutectic phase at the bonding interface of each bonding plate was measured. FIG. 9 shows the relationship between the shear separation load (N) and the thickness (μm) of the eutectic phase.
Shown in
【００４３】図９から明らかなように、共晶相の厚さ
（μｍ）が約10μｍを超えると、剪断剥離負荷が急激に
減少する。これから、銅管／アルミニウム管の接合部に
おける共晶相の厚さは10μｍ以下にする必要があること
が分かる。As is apparent from FIG. 9, when the thickness (μm) of the eutectic phase exceeds about 10 μm, the shear peeling load decreases sharply. This indicates that the thickness of the eutectic phase at the joint between the copper tube and the aluminum tube needs to be 10 μm or less.
【００４４】実施例１ １．接合体の製造 外径8.0 mm、肉厚0.6 mm及び長さ90mmの脱酸銅製の管１
と、外径8.0 mm、肉厚0.6 mm及び長さ150 mmのアルミニ
ウム（純度99.3％）製管２とを用意した。銅管１の先端
から13mmの長さの部分にテーパ加工を施して、直線的に
径が減少し、先端外径が6.2mm のテーパ部11を形成し
た。 Embodiment 1 1. Manufacture of bonded body Deoxidized copper tube 1 with outer diameter 8.0 mm, wall thickness 0.6 mm and length 90 mm
And an aluminum (purity 99.3%) tube 2 having an outer diameter of 8.0 mm, a wall thickness of 0.6 mm, and a length of 150 mm. A portion having a length of 13 mm from the tip of the copper tube 1 was tapered to form a tapered portion 11 having a linearly reduced diameter and a tip outer diameter of 6.2 mm.
【００４５】図６に示すように、銅管１を長さ約40mmの
ステンレス製の２つ割りのクランプ片（図示せず）でし
っかり保持するとともに、アルミニウム管２も長さ約60
mmの２つ割りのクランプ片５ａ、５ｂで保持した。クラ
ンプ片５ａ、５ｂの内面の同径部７ａの長さは５mmであ
り、テーパ部７ｂの長さは６mmであった。この状態で２
つ割りの高周波加熱コイル４を閉じて銅管１のテーパ部
11の周囲に位置するようにし、窒素ガス吹き付け管６よ
り窒素ガスをテーパ部11の周囲に流しながら、高周波電
源より約20ｋｗ及び90ｋＨｚの電流を高周波加熱コイル
４に10秒間流した。テーパ部11の温度が約750 ℃に達し
たら、高周波加熱コイル４への通電量を減少させ、接合
部の温度を約560 ℃に維持しながら銅管１のテーパ部11
を50mm／秒の速度でアルミニウム管２内に圧入した。As shown in FIG. 6, the copper tube 1 is firmly held by a stainless steel clamp having a length of about 40 mm (not shown), and the aluminum tube 2 is also about 60 mm in length.
It was held by the clamp pieces 5a and 5b divided into 2 mm. The length of the same diameter portion 7a on the inner surface of the clamp pieces 5a and 5b was 5 mm, and the length of the tapered portion 7b was 6 mm. In this state 2
Close the split high-frequency heating coil 4 and taper the copper tube 1
A current of about 20 kW and 90 kHz was passed from the high frequency power supply to the high frequency heating coil 4 for 10 seconds while flowing nitrogen gas from the nitrogen gas blowing pipe 6 around the tapered portion 11. When the temperature of the tapered portion 11 reaches about 750 ° C., the amount of current supplied to the high-frequency heating coil 4 is reduced, and the tapered portion 11 of the copper tube 1 is maintained while maintaining the temperature of the joint at approximately 560 ° C.
Was pressed into the aluminum tube 2 at a speed of 50 mm / sec.
【００４６】銅管１のテーパ部11をアルミニウム管２内
に圧入すると、両管の界面に銅／アルミニウムの共晶相
が形成され、余分の共晶相は銅管１及びアルミニウム管
２の先端からそれぞれ排出された。銅管１の圧入完了後
直ちに銅管１内に圧縮空気を流して、接合部を急冷し
た。When the tapered portion 11 of the copper tube 1 is pressed into the aluminum tube 2, a eutectic phase of copper / aluminum is formed at the interface between the two tubes. Respectively. Immediately after the completion of the press-fitting of the copper tube 1, compressed air was flowed into the copper tube 1 to rapidly cool the joint.
【００４７】２．接合体の評価 得られた銅管／アルミニウム管の接合体を長手方向に切
断し、接合界面における共晶相の厚さを光学顕微鏡観測
により測定した。この測定を10本の接合体に対して行
い、アルミニウム管２の先端からの長さに対する共晶相
の厚さ分布を求めた。結果を図10に示す。図10において
ハッチングは測定データのバラツキの範囲を表す。図10
から明らかなように、共晶相の厚さが10μｍ以下の領域
は2.8mm であった。2. Evaluation of joined body The obtained joined body of the copper tube / aluminum tube was cut in the longitudinal direction, and the thickness of the eutectic phase at the joining interface was measured by optical microscope observation. This measurement was performed for ten bonded bodies, and the thickness distribution of the eutectic phase with respect to the length from the tip of the aluminum tube 2 was obtained. The results are shown in FIG. In FIG. 10, hatching indicates a range of variation of the measurement data. FIG.
As is clear from the figure, the area where the thickness of the eutectic phase was 10 μm or less was 2.8 mm.
【００４８】次に各20本ずつの銅管／アルミニウム管の
接合体を万力（バイス) で挟んで、40％の圧縮率まで段
階的に圧縮した。圧縮した接合体の一端を密封し、他端
から接合体内を10 kgf/cm 2 の圧縮空気により加圧し、
水中に浸漬して空気の漏れの有無をテストした。このテ
ストを各圧縮率毎に20本の接合体に対して行った。測定
結果を表１に示す。Next, each of the twenty copper / aluminum pipe joints was sandwiched between vices and stepwise compressed to a compression ratio of 40%. One end of the compressed joined body is sealed, and the joined body is pressurized from the other end with 10 kgf / cm 2 of compressed air,
They were immersed in water and tested for air leakage. This test was performed on 20 joints at each compression ratio. Table 1 shows the measurement results.
【００４９】比較例１ アルミニウム管２の後部のみを通常のクランプ片で固定
し先端部（接合部）は開放状態とした以外は、実施例１
と同じ条件で銅管／アルミニウム管の接合体を作製し
た。実施例１と同様にして共晶相の厚さを測定し、アル
ミニウム管２の先端からの長さに対する共晶相の厚さ分
布を求めた。結果を図10に示す。図10から明らかなよう
に、共晶相の厚さは全接合領域で15μｍ以上であった。
次に各接合体に対して実施例１と同様にして気密性テス
トを行った。測定結果を表１に示す。 Comparative Example 1 Example 1 was repeated except that only the rear part of the aluminum tube 2 was fixed with a normal clamp piece and the tip part (joined part) was opened.
Under the same conditions as in the above, a joined body of a copper tube / aluminum tube was produced. The thickness of the eutectic phase was measured in the same manner as in Example 1, and the thickness distribution of the eutectic phase with respect to the length from the tip of the aluminum tube 2 was obtained. The results are shown in FIG. As is clear from FIG. 10, the thickness of the eutectic phase was 15 μm or more in the entire bonding region.
Next, an airtightness test was performed on each joined body in the same manner as in Example 1. Table 1 shows the measurement results.
【００５０】 表１ 漏れ発生率（％）ｎ＝20圧縮率（％） 実施例１ 比較例１ ０ 0 0 11〜20 0 50 21〜30 5 70 31〜40 20 90Table 1 Leakage generation rate (%) n = 20 Compression rate (%) Example 1 Comparative example 100 0 0 11 to 20 0 50 21 to 30 5 70 31 to 40 20 90
【００５１】表１の結果から明らかなように、両者とも
ゼロ圧縮の場合には良好な耐漏れ性を有する。ところが
20％まで圧縮すると、実施例１の接合体では漏れ発生率
が０％であるのに対して、比較例１の接合体では50％に
も達した。20％超の圧縮率は実用上要求される耐用レベ
ル以上であるので、本発明の銅管／アルミニウム管の接
合体は十分に実用に耐える耐圧縮性を有することがわか
る。As is evident from the results in Table 1, both have good leakage resistance in the case of zero compression. However
When compressed to 20%, the leak rate of the joined body of Example 1 was 0%, while that of the joined body of Comparative Example 1 reached 50%. Since the compression ratio of more than 20% is equal to or higher than the service level required for practical use, it can be seen that the copper / aluminum tube joint of the present invention has sufficient compression resistance for practical use.
【００５２】[0052]
【発明の効果】以上詳述した通り、本発明によりアルミ
ニウム管の先端部をクランプで固定した状態で銅管のテ
ーパ部を圧入することにより、銅管／アルミニウム管の
界面に薄い共晶相を形成し、もって優れた耐漏れ性を有
する接合体が得られる。本発明の銅管／アルミニウム管
の接合体は、極めて薄い共晶相のために機械的変形があ
っても気密性が良好に保持される。また本発明の接合方
法はアルミニウム管の先端部に銅管のテーパ部を圧入す
る方式であるので、高い気密性を有する銅管／アルミニ
ウム管の接合体を安価に効率良く得ることができ、製品
歩留りも良好である。As described above in detail, according to the present invention, a thin eutectic phase is formed at the copper / aluminum tube interface by press-fitting the tapered portion of the copper tube while fixing the tip of the aluminum tube with a clamp. Thus, a joined body having excellent leakage resistance can be obtained. The copper / aluminum tube joined body of the present invention can maintain good airtightness even if there is mechanical deformation due to an extremely thin eutectic phase. In addition, since the joining method of the present invention is a method in which a tapered portion of a copper tube is press-fitted into a tip portion of an aluminum tube, a copper / aluminum tube joined body having high airtightness can be obtained efficiently at low cost. The yield is also good.
【図１】 本発明の一実施例により銅管／アルミニウム
管の接合体を製造する装置を示す要部概略断面図であ
る。FIG. 1 is a schematic sectional view showing a main part of an apparatus for manufacturing a copper tube / aluminum tube assembly according to an embodiment of the present invention.
【図２】 本発明の別の実施例による銅管のテーパ部を
示す断面図である。FIG. 2 is a cross-sectional view illustrating a tapered portion of a copper tube according to another embodiment of the present invention.
【図３】 図２の銅管のテーパ部の表面傾斜を示す概略
図である。FIG. 3 is a schematic view showing a surface inclination of a tapered portion of the copper tube of FIG. 2;
【図４】 本発明のさらに別の実施例による銅管のテー
パ部を示す断面図である。FIG. 4 is a sectional view showing a tapered portion of a copper tube according to still another embodiment of the present invention.
【図５】 窒素ガス吹き付け管を示す概略図である。FIG. 5 is a schematic view showing a nitrogen gas blowing tube.
【図６】 図１の装置において銅管を圧入する直前の状
態を示す概略断面図である。FIG. 6 is a schematic sectional view showing a state immediately before press-fitting a copper tube in the apparatus of FIG. 1;
【図７】 図１の装置において銅管を圧入した後の状態
を示す概略断面図である。FIG. 7 is a schematic sectional view showing a state after press-fitting a copper tube in the apparatus of FIG. 1;
【図８】 参考例１において使用した圧着用工具及びそ
れにより圧着した両板を示す概略図である。FIG. 8 is a schematic view showing a crimping tool used in Reference Example 1 and both plates crimped by the tool.
【図９】 剪断剥離負荷と共晶相の厚さとの関係を示す
グラフである。FIG. 9 is a graph showing the relationship between the shear separation load and the thickness of the eutectic phase.
【図10】 アルミニウム管の先端からの長さに対する共
晶相の厚さの分布を示すグラフである。FIG. 10 is a graph showing the distribution of the thickness of the eutectic phase with respect to the length from the tip of the aluminum tube.
１・・・・・銅管 11、12・・・テーパ部 11ａ、12ａ・凸曲面部 11ｂ・・・・縮径部 ２・・・・・アルミニウム管 ４・・・・・高周波加熱コイル ５・・・・・アルミニウム管用クランプ ５ａ、５ｂ・クランプ片 ６・・・・・窒素ガス吹き付け管 ７ａ・・・・先端同径部 ７ｂ・・・・テーパ部 ７ｃ・・・・後端同径部 1 ···· Copper tube 11, 12 ··· Tapered portion 11a, 12a · Convex curved surface portion 11b · · · Reduced diameter portion 2 ··· Aluminum tube 4 ··· High frequency heating coil 5 · ···· Aluminum tube clamp 5a, 5b · Clamp piece 6 ··· Nitrogen gas spraying tube 7a ··· Equal diameter part 7b ··· Tapered part 7c ··· Equal diameter part at rear end
フロントページの続き (51)Int.Cl.6 識別記号 ＦＩ Ｆ２８Ｆ 1/00 Ｆ２８Ｆ 1/00 Ｅ // Ｂ２３Ｋ 103:18 Continued on the front page (51) Int.Cl. 6 Identification code FI F28F 1/00 F28F 1/00 E // B23K 103: 18
Claims (7)
銅管の外径より小さい内径を有するアルミニウム管に圧
入されてなる接合体において、前記銅管の外面と前記ア
ルミニウム管の内面との界面に前記テーパ部の半分以上
の長さにわたって銅とアルミニウムとの共晶相が形成さ
れており、かつ前記共晶相のうち厚さ10μｍ以下の領域
の長さが１mm以上であることを特徴とする接合体。1. A joined body in which a tapered portion formed at an end of a copper tube is press-fitted into an aluminum tube having an inner diameter smaller than an outer diameter of the copper tube, wherein an outer surface of the copper tube and an inner surface of the aluminum tube are provided. A eutectic phase of copper and aluminum is formed at an interface with at least half of the length of the tapered portion, and a length of a region having a thickness of 10 μm or less in the eutectic phase is 1 mm or more. A joined body characterized by the above.
ウム管との接合体において、前記銅管のテーパ部の長さ
は前記銅管の外径の１〜３倍であり、かつ前記テーパ部
の平均傾斜角は１〜８°であることを特徴とする接合
体。2. The joined body of a copper tube and an aluminum tube according to claim 1, wherein a length of the tapered portion of the copper tube is 1 to 3 times an outer diameter of the copper tube, and A joined body characterized in that the average inclination angle of the tapered portion is 1 to 8 °.
いて、(a) 前記アルミニウム管の内径より僅かに大きい
外径を有する前記銅管の端部にテーパ部を形成し、(b)
前記アルミニウム管の外径と実質的に同一の内径を有す
るとともに、先端付近の内面に前記銅管のテーパ部とほ
ぼ同じ傾斜のテーパ部が設けられているクランプによ
り、前記アルミニウム管の先端部を把持・固定し、(c)
前記銅管のテーパ部を、銅／アルミニウムの共晶温度以
上でアルミニウムの融点未満の温度に加熱し、(d) 前記
銅管のテーパ部を前記クランプで固定した前記アルミニ
ウム管の先端部内に圧入し、もって前記銅管の外面と前
記アルミニウム管の内面との界面に銅／アルミニウムの
共晶相を形成させることにより、両者を密封状態に接合
することを特徴とする接合方法。3. A method for joining a copper tube and an aluminum tube, comprising: (a) forming a tapered portion at an end of the copper tube having an outer diameter slightly larger than the inner diameter of the aluminum tube;
The clamp has substantially the same inner diameter as the outer diameter of the aluminum tube, and has a tapered portion having the same inclination as the tapered portion of the copper tube on the inner surface near the distal end. Hold and fix, (c)
Heating the tapered portion of the copper tube to a temperature equal to or higher than the eutectic temperature of copper / aluminum and lower than the melting point of aluminum, and (d) press-fitting the tapered portion of the copper tube into a tip portion of the aluminum tube fixed by the clamp. A joining method characterized by forming a eutectic phase of copper / aluminum at an interface between the outer surface of the copper tube and the inner surface of the aluminum tube, thereby joining the two in a sealed state.
との接合方法において、前記銅管の圧入後、直ちに接合
部を急冷することを特徴とする接合方法。4. The joining method according to claim 3, wherein the joint is quenched immediately after press-fitting the copper tube.
ウム管との接合方法において、前記クランプ内面のテー
パ部は前記銅管のテーパ部とほぼ同一の傾斜を有するこ
とを特徴とする接合方法。5. The method for joining a copper tube and an aluminum tube according to claim 3 or 4, wherein the tapered portion on the inner surface of the clamp has substantially the same inclination as the tapered portion of the copper tube. Method.
アルミニウム管との接合方法において、前記アルミニウ
ム管の圧入速度が10mm／秒以上であることを特徴とする
接合方法。6. The method for joining a copper tube and an aluminum tube according to claim 3, wherein the press-fitting speed of the aluminum tube is 10 mm / sec or more.
アルミニウム管との接合方法において、前記銅管のテー
パ部の長さは前記銅管の外径の１〜３倍であり、かつ前
記テーパ部の平均傾斜角は１〜８°であることを特徴と
する接合方法。7. The method for joining a copper tube and an aluminum tube according to claim 3, wherein a length of the tapered portion of the copper tube is 1 to 3 times an outer diameter of the copper tube. And a mean inclination angle of the tapered portion is 1 to 8 °.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20525697A JP3311649B2 (en) | 1997-07-15 | 1997-07-15 | Joint and joining method of copper tube and aluminum tube |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20525697A JP3311649B2 (en) | 1997-07-15 | 1997-07-15 | Joint and joining method of copper tube and aluminum tube |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH1133747A true JPH1133747A (en) | 1999-02-09 |
| JP3311649B2 JP3311649B2 (en) | 2002-08-05 |
Family
ID=16503983
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20525697A Expired - Fee Related JP3311649B2 (en) | 1997-07-15 | 1997-07-15 | Joint and joining method of copper tube and aluminum tube |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3311649B2 (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1299038C (en) * | 2005-02-24 | 2007-02-07 | 左铁军 | Copper-aluminium combined pipeline for refrigerating system and its preparing method |
| WO2008034320A1 (en) * | 2006-09-20 | 2008-03-27 | Tiejun Zuo | A non-eutectic structure weld joint of copper-aluminum thin wall pipe and its manufacturing method |
| CN100445623C (en) * | 2006-09-20 | 2008-12-24 | 左铁军 | Refrigeration pipe composed of copper elbow and U pipe of aluminum, and preparation method |
| JP2009072820A (en) * | 2007-09-24 | 2009-04-09 | Mitsubishi Electric Corp | Joined body, joining method and joining apparatus of copper tube with aluminum tube, and fluid circuit device |
| JP2009192191A (en) * | 2008-02-18 | 2009-08-27 | Hitachi Cable Ltd | Heat exchanger and its manufacturing method |
| JP2011179779A (en) * | 2010-03-03 | 2011-09-15 | Mitsubishi Electric Corp | Twisted tube type heat exchanger for water heater and heat pump type water heater including the same |
| WO2012122842A1 (en) * | 2011-03-15 | 2012-09-20 | Zuo Tiejun | Method for preparing copper-aluminum welded joint of capillary and sleeved copper-end aluminum capillary |
| KR101388191B1 (en) * | 2012-06-08 | 2014-04-23 | 김호영 | connecting method of pipe |
| US9950381B2 (en) | 2014-07-30 | 2018-04-24 | Haier Us Appliance Solutions, Inc. | Tube coupling and a method for forming a tube coupling |
| CN109277685A (en) * | 2018-11-20 | 2019-01-29 | 上海理工大学 | A kind of different metal materials pipeline welding device |
| JP2021115836A (en) * | 2020-01-29 | 2021-08-10 | 国立大学法人広島大学 | Laser welding device and laser welding method |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102284788A (en) * | 2011-07-14 | 2011-12-21 | 江苏金鑫电器有限公司 | Pressure deposition welding method for aluminum and copper dissimilar metals |
-
1997
- 1997-07-15 JP JP20525697A patent/JP3311649B2/en not_active Expired - Fee Related
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1299038C (en) * | 2005-02-24 | 2007-02-07 | 左铁军 | Copper-aluminium combined pipeline for refrigerating system and its preparing method |
| WO2008034320A1 (en) * | 2006-09-20 | 2008-03-27 | Tiejun Zuo | A non-eutectic structure weld joint of copper-aluminum thin wall pipe and its manufacturing method |
| CN100445623C (en) * | 2006-09-20 | 2008-12-24 | 左铁军 | Refrigeration pipe composed of copper elbow and U pipe of aluminum, and preparation method |
| KR101057068B1 (en) | 2006-09-20 | 2011-08-16 | 위에 자오 | Welding seams of non-eutectic structures of copper-aluminum thin-walled pipes and methods for their preparation |
| JP2009072820A (en) * | 2007-09-24 | 2009-04-09 | Mitsubishi Electric Corp | Joined body, joining method and joining apparatus of copper tube with aluminum tube, and fluid circuit device |
| JP2009192191A (en) * | 2008-02-18 | 2009-08-27 | Hitachi Cable Ltd | Heat exchanger and its manufacturing method |
| JP2011179779A (en) * | 2010-03-03 | 2011-09-15 | Mitsubishi Electric Corp | Twisted tube type heat exchanger for water heater and heat pump type water heater including the same |
| WO2012122842A1 (en) * | 2011-03-15 | 2012-09-20 | Zuo Tiejun | Method for preparing copper-aluminum welded joint of capillary and sleeved copper-end aluminum capillary |
| KR101388191B1 (en) * | 2012-06-08 | 2014-04-23 | 김호영 | connecting method of pipe |
| US9950381B2 (en) | 2014-07-30 | 2018-04-24 | Haier Us Appliance Solutions, Inc. | Tube coupling and a method for forming a tube coupling |
| CN109277685A (en) * | 2018-11-20 | 2019-01-29 | 上海理工大学 | A kind of different metal materials pipeline welding device |
| JP2021115836A (en) * | 2020-01-29 | 2021-08-10 | 国立大学法人広島大学 | Laser welding device and laser welding method |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3311649B2 (en) | 2002-08-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3311649B2 (en) | Joint and joining method of copper tube and aluminum tube | |
| JP5310714B2 (en) | Metal tube joining structure and heat exchanger | |
| US5956846A (en) | Method and apparatus for controlled atmosphere brazing of unwelded tubes | |
| KR101256973B1 (en) | Liquid phase diffusion bonding pipe joint and manufacturing method therefor | |
| JPH0985467A (en) | Joined body between copper tube and aluminum tube and joining method | |
| US6871774B2 (en) | Aluminum tubular heat exchanger and method of construction | |
| JP5008508B2 (en) | Bonded body of copper tube and aluminum tube, bonding method, bonding device, and fluid circuit device | |
| TW202320946A (en) | Stainless steel and copper joint, manufacturing method therefor, and stainless steel and copper joining method | |
| JPH0819876A (en) | Lap joining equipment for dissimilar metal tube | |
| KR20220107918A (en) | Heater plate and method for manufacturing heater plate | |
| JP2006231349A (en) | Heat exchanger | |
| JPH10296432A (en) | High frequency brazing method | |
| JP4461525B2 (en) | Bonded body of copper tube and aluminum tube and heat exchanger provided with the same | |
| JPH05264185A (en) | Heat pipe container | |
| CN208117070U (en) | Weld Cooling fixture and its zirconium-base amorphous welding equipment | |
| JPH1094879A (en) | Pipe frame joined structure and joining method therefor | |
| JP4264775B2 (en) | Dissimilar metal joining method | |
| JP2005308293A (en) | Heat exchanger and its manufacturing method | |
| JPH11216576A (en) | Connection of copper pipe and aluminum pipe | |
| JP2010247194A (en) | Method of joining metallic tube | |
| KR200270457Y1 (en) | A accumulator of cooling equipment | |
| JPS58168487A (en) | Production of internally finned heat transmission pipe | |
| JPH03204130A (en) | Manufacture of flat tube for heat exchanger | |
| JPS6177678A (en) | Method of bonding metal cylindrical body for ceramic cylindrical structural member | |
| WO2005075925A1 (en) | Heat exchanger manufacturing method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| LAPS | Cancellation because of no payment of annual fees |