JP2004314115A

JP2004314115A - Heat transfer element, and method for manufacturing the same

Info

Publication number: JP2004314115A
Application number: JP2003110413A
Authority: JP
Inventors: Hisashi Hori; 久司堀; Shinya Makita; 慎也牧田
Original assignee: Nippon Light Metal Co Ltd
Current assignee: Nippon Light Metal Co Ltd
Priority date: 2003-04-15
Filing date: 2003-04-15
Publication date: 2004-11-11
Anticipated expiration: 2023-04-15
Also published as: JP4325260B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat transfer element of excellent heat transfer property in which a pipe for heating medium or a heater is tightly fitted to a base member with the pipe or the heater built therein, and a heat transfer manufacturing method for reliably manufacturing the same. <P>SOLUTION: The heat transfer element 1 comprises a base member 2 having a lid trough 6 of rectangular section which is opened in a face side 3 and a recessed trough 8 which is opened in a bottom side of the lid trough 6, a pipe 16 for heating medium which is inserted in the recessed trough 8 of the base member 2, and a lid plate 10 to be fitted to the lid trough 6 of the base member 2. Joined parts W1 and W2 by the friction stirring and joining are formed along each butted surface of both side walls 5 and 5 in the lid trough 6 of the base member 2 and both side surfaces 13 and 14 of the lid plate 10. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、例えば熱交換機や加熱機器あるいは冷却機器などに用いられる伝熱素子およびその製造方法に関する。
【０００２】
【従来の技術】
熱交換、加熱、あるいは冷却すべき対象物に接触または近接して配置される伝熱素子は、その本体であるベース部材に例えば冷却水などの熱媒体を循環させるパイプを密着させて内蔵することが求められている。
係る伝熱素子の製造方法としては、例えばステンレス鋼からなるパイプを鋳型に内設した所定のキャビティ中に貫通させて配置し、係るキャビティ内に例えばアルミニウム合金の溶湯を鋳込んで一体化させる鋳包み方法がある。
しかしながら、上記鋳包み方法では、鋳造の後でベース部材となるアルミニウム合金が凝固する際に収縮するため、得られるベース部材と上記パイプとの間に隙間が生じる。この結果、上記パイプ中を循環する熱媒体からベース部材への熱伝達性が低下する、という問題があった。しかも、鋳型の制作費が高いため、比較的大型の伝熱素子を少量製造する際には、コスト高になる問題もあった。
【０００３】
一方、異なる伝熱素子の製造方法としては、アルミニウム合金からなるベース部材の表面に形成した溝内に、例えばステンレス鋼からなるパイプ、または周囲にステンレス鋼の箔を巻き付けたヒータを挿入し且つ上記溝の開口部を覆うようにベース部材の表面に蓋板をロウ付けする方法がある。
しかしながら、上記ロウ付けを用いる方法では、例えば上記溝にヒータを挿入した場合、その発熱によりロウ材の接合強度が低下したり、係る事態に伴って蓋板が緩んでヒータとベース部材間の熱伝達性が低下する、という問題があった。しかも、ベース部材となるアルミニウム合金のうち、高温強度が高い２０００系あるいは５０００系の合金では、ロウ付けができない、という問題もあった。
【０００４】
【発明が解決すべき課題】
本発明は、以上に説明した従来の技術における問題点を解決し、熱媒体用のパイプまたはヒータとこれを内蔵するベース部材とが密着した熱伝達性に優れた伝熱素子、およびこれを確実に製造できる伝熱素子の製造方法を提供する、ことを課題とする。
【０００５】
【課題を解決するための手段および発明の効果】
本発明は、上記課題を解決するため、ベース部材に形成した蓋溝の底面に開口する凹溝などに熱媒体用のパイプなどを密着可能に挿入し、且つ上記蓋溝にほぼ同一断面の蓋板を嵌合すると共に、係る蓋板とベース部材とを固相状態で一体化する摩擦攪拌接合する、ことに着想して成されたものである。
即ち、本発明の第１の伝熱素子（請求項１）は、表面に開口する断面が矩形の蓋溝および係る蓋溝の底面に開口する凹溝を有するベース材と、係るベース材の凹溝に挿入される熱媒体用のパイプまたはヒータと、上記ベース材の蓋溝に嵌合される蓋板と、を備え、上記ベース材の蓋溝における両側壁と蓋板の両側面との各突き合わせ面に沿って摩擦攪拌接合による接合部が形成されている、ことを特徴とする。
また、本発明の第２の伝熱素子（請求項２）は、表面に開口する断面が矩形の蓋溝および係る蓋溝の底面に開口する凹溝を有するベース材と、係るベース材の蓋溝に嵌合され且つ底面に開口する凹溝を有する蓋板と、上記ベース材の凹溝と前記蓋板の凹溝とに跨って挿入される熱媒体用のパイプまたはヒータと、を備え、上記ベース材の蓋溝における両側壁と蓋板の両側面との各突き合わせ面に沿って摩擦攪拌接合による接合部が形成されている、ことを特徴とする。
【０００６】
これらによれば、ベース部材と蓋板とは、両者の金属材料が固相状態で一体化される摩擦攪拌接合による接合部を介して接合されているため、蓋溝の底面に開口する凹溝に、または係る凹溝と蓋板の凹溝とに跨って、挿入したパイプまたはヒータからの熱による上記接合部における強度の低下をなくすことができる。しかも、摩擦攪拌接合の際に後述する接合シールにより蓋板とベース部材とが加圧されているため、第１の伝熱素子では、係る蓋板の底面に接触ないし押圧されるパイプなどは、当該ベース部材の凹溝と面接触しつつ密着する。一方、第２の伝熱素子では、パイプなどは、ベース部材の凹溝および蓋板の底面に位置する凹溝の全周面で面接触しつつ密着する。従って、上記パイプ中などを循環する熱媒体やヒータからの熱エネルギを効率良くベース部材を介して、伝熱すべき対象物に熱伝達することが可能となる。
尚、ベース部材および蓋板の材質は、特に限定されないが、特に高い熱伝導率で且つ加工性に優れたアルミニウム合金が推奨される。また、ベース部材および蓋板がアルミニウム合金からなる場合、前記パイプは、アルミニウム合金よりも高融点で且つ剛性の高いステンレス鋼管が望ましく、前記ヒータは、公知の電熱線の周囲にステンレス鋼の箔を巻き付けた形態が推奨される。更に、ベース部材は、蓋溝と凹溝を一体に成形できるアルミニウム合金の押出形材とし、第２の伝熱素子に用いる蓋板も凹溝を有する同様の押出形材としても良い。
【０００７】
一方、本発明の伝熱素子の製造方法（請求項３）は、ベース部材の表面に開口する断面が矩形の蓋溝の底面に設けた凹溝に、または係るベース材の凹溝と上記蓋溝に嵌合される蓋板の底面に設けた凹溝とに跨って、熱媒体用のパイプまたはヒータを挿入する挿入工程と、上記ベース部材の蓋溝に断面がほぼ同じ上記蓋板を嵌合する閉塞工程と、上記ベース材の蓋溝における両側壁と上記蓋板の両側面との各突き合わせ面に沿って、摩擦攪拌接合を施す接合工程と、を含む、ことを特徴とする。
これによれば、ベース部材および蓋板を、両者の金属材料を固相状態で一体化する摩擦攪拌接合による接合部を介して強固に接合できる。しかも、前記蓋板の底面に凹溝がない形態では、ベース部材および蓋板を加圧しつつ接合するため、当該蓋板の底面がパイプまたはヒータに接触ないし押圧し、当該パイプなどとベース部材の凹溝とを広い面接触により密着させることができる。また、蓋板の底面にも凹溝がある形態では、パイプなどをベース部材および蓋板の各凹溝に全周面で面接触させつつ、密着させることができる。従って、熱伝達性に優れると共に、パイプやヒータなどからの熱エネルギによっても高い強度を維持できる接合部を有する伝熱素子を効率良く確実に製造することが可能となる。
【０００８】
尚、ベース部材および蓋板の材質は、摩擦攪拌接合が異種金属間にも適用可能であるため、両者が同種のアルミニウム合金同士からなる場合のほか、異種のアルミニウム合金の組み合わせからなる場合も含まれる。また、ベース部材および蓋板がアルミニウム合金同士からなる場合、前記摩擦攪拌接合する際の接合温度が５００℃以下の温度域であるため、予め前記ベース部材や蓋板の凹溝に挿入したヒータの特性が劣化することも防止できる。
【０００９】
また、本発明には、前記ベース板の凹溝の少なくとも下半部の断面形状は、前記パイプまたはヒータの下半部の断面形状と同じか、あるいは係る断面形状とほぼ相似形である、伝熱素子の製造方法（請求項４）も含まれる。これによれば、パイプまたはヒータとベース板の凹溝の内壁や凹溝がない蓋板との接触面積を、係るパイプの全周面またはその５０％以上にして密着させることができる。従って、パイプまたはヒータからの熱エネルギを確実にベース部材に伝達させられる。尚、パイプやヒータの断面が円形で且つ蓋板の底面が平坦な場合、ベース板の凹溝の下半部は、半円形の断面となり、パイプなどの断面が六角形以上の正多角形で且つ蓋板の底面が平坦な場合、凹溝の下半部は、長方形または台形などになり、断面の下半部で凹溝の内壁と面接触する。また、パイプなどの断面が正方形の場合、これとほぼ同じ正方形を呈する断面ベース部材の凹溝に挿入することで、当該パイプの全周面で係る凹溝および蓋板における凹溝のない底面と面接触が可能となる。一方、蓋板の底面に凹溝が位置する形態では、係る蓋板の凹溝とベース板の凹溝とは、対称で且つ同じ半円形または長方形の断面となる。
【００１０】
更に、本発明には、前記蓋板の底面に凹溝がない形態における前記ベース板の前記凹溝の深さは、前記パイプまたはヒータの外径ないし係る外径の１．２倍未満の範囲にある、伝熱素子の製造方法（請求項５）も含まれる。これによれば、パイプまたはヒータの少なくとも下半部の周面を、ベース板の凹溝の内壁と確実に面接触により確実に密着させることができる。
尚、ベース板の凹溝の深さがパイプなどの外径よりも小さいと、パイプなどの全断面が凹溝内に挿入できなくなる。一方、上記凹溝の深さがパイプなどの外径の１．２倍以上になると、蓋板による押さえ込みがなくなり、パイプなどと上記凹溝の内壁との間に隙間を生じる。このため、係る範囲を除外したものである。
【００１１】
また、本発明には、前記凹溝の幅は、前記パイプまたはヒータの外径ないし係る外径の１．１倍の範囲にある、伝熱素子の製造方法（請求項６）も含まれる。
これによっても、パイプまたはヒータの少なくとも下半部の周面または全周面を、ベース部材の凹溝あるいはこれと蓋板底面の凹溝と確実に面接触により確実に密着させることができる。尚、ベース部材や蓋板の凹溝の幅がパイプなどの外径よりも小さいと、係る凹溝にパイプなどが挿入できなくなり、凹溝の幅がパイプなどの外径の１．１倍を越えると、パイプなどと凹溝の内壁との間に隙間を生じる。このため、係る範囲を除外したものである。尚また、以上の凹溝の深さおよび幅の範囲は、前記ベース部材や蓋板がアルミニウム合金からなり、パイプなどが高い剛性のステンレス鋼管からなる場合に特に好適である。
【００１２】
加えて、本発明には、前記接合工程における摩擦攪拌接合に用いる接合ツールは、ツール本体とその底面の中心部から同軸心で垂下する摩擦攪拌ピンとを含み、上記摩擦攪拌ピンの軸方向の長さは、前記突き合わせ面の深さ乃至その６０％以上の範囲にある、伝熱素子の製造方法（請求項７）も含まれる。
これによれば、ベース部材と蓋板との突き合わせ面付近の表面を高速回転する接合ツールのツール本体で押さえ込みつつ、係るツール本体と共に高速回転して突き合わせ面付近に進入する摩擦攪拌ピンにより、ベース部材および蓋板を形成する金属材料を摩擦熱にて固相状態で流動化させて攪拌することができる。このため、蓋板をベース部材の蓋溝内に嵌合した状態で強固に接合できる。しかも、凹溝のない蓋板の底面に接近するパイプなどを、ベース部材の凹溝内に押し込んだり、ベース部材の凹溝と蓋板の凹溝との全周面で面接触させることができる。従って、パイプなどの周面と凹溝の内壁とを面接触により確実に密着できる。
尚、摩擦攪拌ピンの軸方向の長さが突き合わせ面の深さの６０％未満になると、該突き合わせ面に沿って形成される接合部の深さが上記深さの約半分近くになり、接合強度が不足する事態になり得る。また、摩擦攪拌ピンの軸方向の長さが突き合わせ面の深さよりも長いと、流動化した金属材料が蓋溝と蓋板との間に進入して接合部の強度が不足するため、係る範囲を除外した。更に、突き合わせ面の深さは、接合ツールの軸方向に沿った押し込み量を差し引いた距離である。
【００１３】
【発明の実施の形態】
以下において、本発明の実施に好適な形態を図面と共に説明する。
図１（Ａ）は、本発明における第１の伝熱素子の１形態である伝熱素子１を示す斜視図であり、図１（Ｂ）は、係る伝熱素子１の垂直断面図である。
伝熱素子１は、図１（Ａ），（Ｂ）に示すように、表面３および裏面４を有する厚板形状のベース部材２と、係るベース部材２の表面３に開口し且つ断面が長方形（矩形）の蓋溝６に嵌合される蓋板１０と、前記蓋溝６の底面に開口する凹溝８に挿入される熱媒体用のパイプ１６と、を備えている。上記ベース部材２は、例えばアルミニウム合金（ＪＩＳ：Ａ６０６１）からなり、図１（Ａ）に示すように、図示の前後（長手）方向に沿って蓋溝６と、その底面の中央に凹溝８とが形成されている。係る凹溝８は、その下半部が断面半円形のアール面（凹溝）７であり、且つ蓋溝６寄りの上半部の断面は、上記アール面７の直径と同じ幅の長方形である。
【００１４】
また、蓋板１０も上記同様のアルミニウム合金からなり、図１（Ａ），（Ｂ）に示すように、ベース部材２の蓋溝６の断面とほぼ同じ長方形（矩形）断面を形成する上面１１、底面１２、および左右の各側面１３，１４を有する。
更に、パイプ１６は、例えばステンレス鋼（ＪＩＳ：ＳＵＳ３０４）からなり、図１（Ｂ）に示すように、その断面のほぼ下半分は、ベース部材２における凹溝８のアール面７とほぼ同じ相似形の半円形を呈する。因みに、係るパイプ１６は、外径が３ｍｍで且つ肉厚が０．５ｍｍのサイズであり、断面円形の中空部１８を内設している。係る中空部１８には、例えば冷却水、冷却ガス、高温液、あるいは高温ガスなど熱媒体が循環して流される。
【００１５】
後述するように、前記ベース部材２の凹溝８の深さは、パイプ１６の外径と同じ深さ乃至係る外径の１．２倍未満の深さの範囲にあると共に、係る凹溝８のアール面７を除いたほぼ上半部の幅は、パイプ１６の外径と同じ幅乃至係る外径の１．１倍以下の深さの範囲にある。従って、パイプ１６の下半部の周面は、凹溝８のアール面７と面接触している。
図１（Ａ），（Ｂ）に示すように、ベース部材２の蓋溝６の両側壁５，５と、係る蓋溝６に嵌合した蓋板１０の両側面１３，１４との突き合わせ面に沿って、摩擦攪拌接合による接合部Ｗ１，Ｗ２が個別に形成されている。係る接合部Ｗ１，Ｗ２は、ベース部材２および蓋板１０の金属材料を、後述する接合ツールを用いて摩擦熱により固相状態で流動化しつつ攪拌して一体化させたものである。因みに、接合部Ｗ１，Ｗ２の深さは、上記突き合わせ面の深さの約８０％である。
【００１６】
以上のような伝熱素子１によれば、ベース部材２と蓋板１０とは、両者の金属材料が固相状態で一体化される摩擦攪拌接合による接合部Ｗ１，Ｗ２を介して接合されている。このため、蓋溝６の底面に開口する凹溝８に挿入したパイプ１６からの熱による接合部Ｗ１，Ｗ２の強度の低下をなくすことができる。しかも、摩擦攪拌接合の際に蓋板１０とベース部材２とが、後述する接合ツールのツール本体の底面（ショルダ）に加圧されているため、蓋板１０の底面１２に接触ないし押圧されるパイプ１６は、凹溝８のアール面７と面接触しつつ密着する。従って、上記パイプ８中を循環する熱媒体からの熱エネルギを効率良くベース部材２を介して、その付近に位置する対象物に熱伝達することができる。
特に、凹溝８の深さおよび幅が、パイプ１６の外径と同じか、これよりも極く僅かに小さい場合には、パイプ１６と凹溝８の内壁との良好な密着が得られる。
【００１７】
次に、前記伝熱素子１の製造方法について、図２〜図３に基づき説明する。
図２（Ａ）は、表面３および裏面４を有し且つ前記同様のアルミニウム合金からなる厚板２ａの断面を示す。係る厚板２ａは、平面視で図示の前後方向が長手方向である長方形を呈する。係る厚板２ａの表面３における長手方向の中央付近に沿って、エンドミルカッタなどを用いて公知の座ぐり加工を施す。その結果、図２（Ｂ）に示すように、表面３に開口し断面が長方形で且つ左右の側壁５，５を備えた蓋溝６を有する厚板２ｂが形成される。
上記厚板２ｂの蓋溝６における底面の中央部に対し、長手方向に沿って所定の幅で座ぐり加工した後、更にその下側を切削加工により半円形断面に切除する。その結果、図２（Ｃ）に示すように、上記蓋溝６およびその底面の中央部に開口する凹溝８を長手方向に沿って有するベース部材２が形成される。係る凹溝８は、上半部の断面が長方形であり、且つ下半部が断面半円形のアール面７である。
【００１８】
尚、ベース部材２には、上記蓋溝６および凹溝８を長手方向に沿って予め一体に形成されているアルミニウム合金の押出形材を用いても良い。
図２（Ｃ）に示すように、凹溝８の深さ（最深部の深さ）Ｙは、次述する熱媒体用のパイプ１６の外径と同じ乃至その１．２倍未満の範囲にあると共に、凹溝８の幅Ｘは、パイプ１６の外径と同じ乃至その１．１倍以下の範囲にある。
次に、図２（Ｄ）に示すように、凹溝８に前記同様のステンレス鋼からなる熱媒体用のパイプ１６を挿入する（挿入工程）。中空部１８を内設する当該パイプ１６の下半部の周面は、その全長において凹溝８の下半部を形成するアール面７と面接触する。また、係るパイプ１６の上端部は、凹溝８の開口部付近で且つ蓋溝６の底面と同じレベルか、あるいは係る底面よりも僅かに低い位置となる。
【００１９】
更に、図３（Ａ）に示すように、凹溝８にパイプ１６が挿入されたベース部材２の蓋溝６内に、前記同様のアルミニウム合金からなり、上面１１、下面１２、左右の側面１３，１４に囲まれた蓋溝６の断面とほぼ同じ長方形断面の蓋板１０を嵌合する（閉塞工程）。この際、蓋板１０の底面１２の中央付近に、パイプ１６の上端部が線接触または接近すると共に、当該蓋板１０の上面１１は、ベース部材２における左右の表面３，３と面一となる。
次いで、図３（Ｂ），（Ｃ）に示すように、ベース部材２の蓋溝６の両側壁５，５と蓋板１０の両側面１３，１４との２列の突き合わせ面に沿って、摩擦攪拌接合を施す（接合工程）。係る接合には、図示の接合ツール２０を用いる。
【００２０】
即ち、接合ツール２０は、例えば工具鋼からなり、図３（Ｂ），（Ｃ）に示すように、円柱形のツール本体２２と、その底面２４の中心部から同軸心で垂下する摩擦攪拌ピン２６とを含む。尚、攪拌ピン２６の周面には、その軸方向に沿って図示しない複数の小溝や径方向に沿ったネジ溝が形成されていても良い。
因みに、上記ツール本体２２の直径は６〜２０ｍｍ、摩擦攪拌ピン２６の長さは３〜１０ｍｍで且つその直径は２〜８ｍｍである。また、摩擦攪拌ツール２０の回転数は５００〜１５０００ｒｐｍ、送り速度は０．０５〜２ｍ／分であり、当該ツール２０の軸方向に加える押し込み力は１ｋＮ〜２０ｋＮ程度である。
【００２１】
図３（Ｂ），（Ｃ）に示すように、ベース材２および蓋板１０を図示しない治具により拘束した状態で、蓋溝６における左側の側壁５と蓋板１０の側面１３との突き合わせ面に沿って、高速回転する接合ツール２０を押し込む。この際、ツール本体２２の底面２４は、ベース部材２の表面３および蓋板１０の上面１１と平行となる。尚、上記摩擦攪拌ピン２６の軸方向の長さは、図３（Ｂ）に示すように、上記突き合わせ面の深さＨ以下で且つその６０％以上の範囲とされる。
図３（Ｂ），（Ｃ）に示すように、摩擦攪拌ツール２０における摩擦攪拌ピン２６の底面は、前記突き合わせ面のやや下方に達する。係る状態で高速回転する摩擦攪拌ピン２６により、その周囲に位置するベース部材２および蓋板１０のアルミニウム合金材料は、摩擦熱によって加熱され、半固相状態で塑性化し且つ流動化（物質移動）する。尚、摩擦攪拌ピン２６の周面に軸方向に沿った小溝や径方向に沿ったネジ溝があると、上記アルミニウム合金材料の攪拌を一層活発化できる。
【００２２】
係る摩擦攪拌ツール２０が回転しつつ通過した跡には、図３（Ｂ），（Ｃ）に示すように、蓋溝６の側壁５と蓋板１０の側面１３との突き合わせ面に沿って、上記塑性・流動化したアルミニウム合金材料が固化した接合部Ｗ１が形成される。係る接合部Ｗ１の内部は、上記合金材料が十分に塑性流動している場合、多数の空孔である微細なトンネル欠陥などが皆無となる。尚、接合部Ｗ１の表面ｗａは、前記ツール本体２２の底面２４の周縁に倣った細かなさざ波形の凹凸を有し、且つツール本体２２の押し込み量によって、表面３などよりも僅かに凹んでいる。引き続いて、蓋溝６における右側の側壁５と蓋板１０の側面１４との突き合わせ面に沿っても、接合ツール２０を用いて上記と同様の摩擦攪拌接合を施す。
【００２３】
その結果、図３（Ｄ）に示すように、蓋溝６の両側壁５，５と蓋板１０の両側面１３，１４との各突き合わせ面に沿って接合部Ｗ１，Ｗ２が形成され、これにより蓋板１０がベース部材２の蓋溝６内に密嵌され且つ係る蓋板１０の底面１２が予め凹溝８中に挿入され且つ下半部で面接触しているパイプ１６の上端部に当接または著しく近接した伝熱素子１が得られる。
以上のような伝熱素子１の製造方法によれば、熱伝達性に優れると共に、パイプ１６からの熱エネルギによっても高い強度を維持できる接合部Ｗ１，Ｗ２を有する伝熱素子１を効率良く確実に製造することが可能となる。尚、パイプ１６に替えて、例えば電熱線などの周囲にステンレス鋼の箔を巻き付けた断面円形のヒータをベース部材２の凹溝８に挿入しても良い。
【００２４】
図４は、異なる形態の伝熱素子１ａおよびその製造方法に関する。
先ず、前記同様のアルミニウム合金製の厚板の表面３を座ぐり加工や切削加工することにより、図４（Ａ）に示すように、表面３に開口する断面長方形（矩形）の蓋溝６と、その底面中央に開口し且つ断面が正方形の凹溝９とを有するベース部材２ｃを形成する。尚、ベース部材２ｃには、上記蓋溝６および凹溝９を長手方向に沿って予め一体に有するアルミニウム合金の押出形材を用いても良い。
次に、上記凹溝９内に、その深さと幅とに縦・横寸法がほぼ同じ正方形断面である熱媒体用のパイプ１７を挿入する（挿入工程）。係るパイプ１７は、前記同様のステンレス鋼からなり、外形と相似形断面の中空部１９を内設していると共に、上記凹溝９の底面および左右の両側壁に面接触する。
【００２５】
次いで、図４（Ｂ）に示すように、凹溝９にパイプ１７が挿入されたベース部材２ｃの蓋溝６内に、前記同様のアルミニウム合金からなり、蓋溝６の断面とほぼ同じ長方形断面の蓋板１０を嵌合する（閉塞工程）。この際、蓋板１０の底面１２の中央付近に、上記パイプ１７の上面が面接触または極く接近し、且つ当該蓋板１０の上面１１は、ベース部材２ｃの表面３，３と面一となる。
そして、蓋溝６における左右の側壁５，５と蓋板１０の側面１３，１４との一対の突き合わせ面に沿って、それぞれ前記同様の接合ツール２０を用いて前記同様の摩擦攪拌接合を個別に施す（接合工程）。
【００２６】
その結果、図４（Ｃ）に示すように、一対の突き合わせ面に沿って接合部Ｗ１，Ｗ２が形成され、これにより蓋板１０がベース部材２ｃの蓋溝６内に密嵌されると共に、係る蓋板１０の底面１２が予め凹溝９中に挿入され且つ面接触しているパイプ１７の上面に面接触または近接して対向する伝熱素子１ａが得られる。
係る伝熱素子１ａは、図４（Ｃ）に示すように、断面正方形（角形）のパイプ１７をほぼ同じか相似形断面の凹溝９に面接触により挿入され且つ係るパイプ１７の上面に蓋板１０の底面１２が面接触または近接しているため、熱伝達特性が一層向上する。また、以上の伝熱素子１ａの製造方法によれば、パイプ１７からの熱エネルギによっても、ベース部材２ｃと蓋板１０との間で高い強度を維持できる接合部Ｗ１，Ｗ２を有する伝熱素子１ａを効率良く確実に製造可能となる。
【００２７】
【実施例】
ここで、本発明の伝熱素子１の具体的な実施例について説明する。
アルミニウム合金（ＪＩＳ：Ａ６０６１）からなり、前記図１（Ａ），（Ｂ）および図４（Ｃ）における長手方向が３００ｍｍ、表面３と裏面４の幅が３０ｍｍ、厚みが２０ｍｍであると共に、蓋溝６は深さ５ｍｍ×幅１０ｍｍである２つのベース部材２，２ｃを用意した。ベース部材２の凹溝８は、深さ（最深部）Ｙ：３ｍｍ×幅Ｘ：３ｍｍで且つ断面の下半部は半円形の前記アール面７である。また、ベース部材２ｃの凹溝９は、深さＹ：３ｍｍ×幅Ｘ：３ｍｍの正方形断面である。
【００２８】
上記ベース部材２の凹溝８にステンレス鋼（ＪＩＳ：ＳＵＳ３０４）製で、全長：３４０ｍｍ×外径：３ｍｍ×肉厚：０．５ｍｍの熱媒体用のパイプ１６を、その両端を突出させて挿入した。一方、ベース部材２ｃの凹溝９に同じ素材で、全長：３４０ｍｍ×縦：３ｍｍ×横：３ｍｍ×肉厚：０．５ｍｍの断面正方形のパイプ１７を、その両端を突出させて挿入した。係るベース部材２，２ｃの蓋溝６に、前記と同じアルミニウム合金からなり、全長３００ｍｍ×幅９．８ｍｍ×厚み５ｍｍの蓋板１０を個別に嵌合した。係る蓋板１０を含む上記ベース部材２，２ｃを拘束した状態で、蓋溝６の両側壁５，５と蓋板１０の両側面１３，１４との一対の突き合わせ面に沿って、摩擦攪拌接合を接合を個別に行った。
【００２９】
これに用いた接合ツール２０は、工具鋼（ＳＫＤ６１）からなり、そのツール本体２２の直径が１５ｍｍで、摩擦攪拌ピン２６は、直径５ｍｍ×長さ３．８ｍｍである。係る接合ツール２０を、上記突き合わせ面に沿って、回転数：１４００ｒｐｍ、移動速度：３００ｍｍ／分、軸方向の押し込み深さ（距離）：０．２ｍｍの同じ条件で、回転しつつ移動させて接合部Ｗ１，Ｗ２を個別に形成した。
ベース部材２を用いた伝熱素子１を実施例１、ベース部材２ｃを用いた伝熱素子１ａを実施例２とした。これらを長手方向の４箇所で切断して目視し、接合部Ｗ１，Ｗ２におけるトンネル欠陥などの有無、パイプ１６と凹溝８，９および蓋板１０との隙間の有無を調べた。その結果を表１に示す。
【００３０】
【表１】

【００３１】
表１によれば、実施例１，２の伝熱素子１，１ａの接合部Ｗ１，Ｗ２には、トンネル欠陥などは全く見当たらなかった。また、実施例１の凹溝８とパイプ１６との下半部間には、隙間がなく、実施例２の蓋板１０の底面１２を含む凹溝９とパイプ１７との間では、全周にて隙間のない密着性を有することが判明した。
次に、前記実施例１と同じベース部材２を１０個用意し、表２に示すように、凹溝８の深さ（最深部）Ｙと幅Ｘを変化させ、前記と同じ熱媒体用のパイプ１６を個別に挿入した。これらの蓋溝６の両側壁５，５と蓋板１０の両側面１３，１４との各突き合わせ面に沿って、前記と同じ接合ツール２０を用い且つ前記と同じ同じ条件により摩擦攪拌接合を個別に行った。
得られた１０の伝熱素子（１）について、前記同様に切断して目視し、接合部Ｗ１，Ｗ２における欠陥などの有無や、パイプ１６と凹溝８および蓋板１０との隙間の有無を調べた。その結果も表２に示す。
【００３２】
【表２】

【００３３】
表２によれば、パイプ１６の外径よりも凹溝８の深さＹが小さい（浅い）比較例１では、蓋板１０の浮き上がりにより、接合部Ｗ１，Ｗ２にトンネル欠陥が生じ、且つパイプ１６と凹溝８のアール面との間に隙間が生じた。また、凹溝８の深さＹがパイプ１６の外径の１．２倍である比較例２では、接合ツール２０の加圧で蓋板１０の中央部が凹み且つ側面１３，１４が浮き上がったため、接合部Ｗ１，Ｗ２にアルミニウム合金材料不足による欠陥が生じ且つ上記隙間も生じた。
更に、凹溝８の幅Ｘがパイプ１６の外径の１．１倍を越えた比較例３〜５では、蓋板１０が上記同様の撓み変形をしたため、接合部Ｗ１，Ｗ２にアルミニウム合金材料不足による欠陥が生じ且つ上記隙間も生じた。
一方、凹溝８の深さＹがパイプ１６の外径と同じかその１．２倍未満であり、凹溝８の幅Ｘがパイプ１６の外径と同じかその１．１倍以下である実施例３〜７では、接合部Ｗ１，Ｗ２にトンネル欠陥などがなく、且つ凹溝８のアール面７とパイプ１６の下半部とに隙間のない良好な密着状態となっていた。
【００３４】
更に、前記実施例１と同じベース部材２、蓋板１０、および熱媒体用のパイプ１６を７組用意し、これらについて前記同様に挿入および嵌合して組立てた。
表３に示すように、前記接合ツール２０における摩擦攪拌ピン２６の軸方向の長さを変化させ、前記ツール本体２２の押し込み量（距離）を一定とし、上記７組の蓋溝６の両側壁５，５と蓋板１０の両側面１３，１４との突き合わせ面に沿って、上記押し込み量を含め前記と同じ条件により摩擦攪拌接合を個別に行った。
得られた７個の伝熱素子（１）について、前記同様に切断して目視し、接合部Ｗ１，Ｗ２における欠陥の有無、および凹溝８とパイプ１６との隙間の有無を調べた。その結果も表３に示す。
【００３５】
【表３】

【００３６】
表３によれば、摩擦攪拌ピン２６の長さが前記突き合わせ面の深さＨ（押し込み量を除いた蓋溝６の深さ）よりも長い比較例６では、塑性流動化したアルミニウム合金材料が蓋溝６と蓋板１０との間に差し込むため、ベース部材２およびパイプ１６と蓋板１０との間に隙間が生じていた。
また、摩擦攪拌ピン２６の長さが前記突き合わせ面の深さＨの６０％未満である比較例７では、上記材料の組成流動および接合ツール２０による加圧およびアルミニウム合金材料の塑性流動が不足し、接合部Ｗ１，Ｗ２の接合強度が低くなっため、パイプ１６と蓋板１０の底面１２との間に隙間が生じていた。
一方、摩擦攪拌ピン２６の長さが前記突き合わせ面の深さＨと同じかその６０％以上であった実施例８〜１２では、接合部Ｗ１，Ｗ２に欠陥がなく、且つパイプ１６と凹溝８との下半部およびパイプ１６の上端部と蓋板１０の底面１２との間には、隙間がなく良好な密着状態となっていた。
以上の実施例１〜１２の伝熱素子１により、本発明の効果が裏付けられた。
【００３７】
図５（Ａ）は、複数の前記伝熱素子１（伝熱素子１ａも含む、以下同じ）を用いた伝熱ユニットＵ１の概略を示す。係る伝熱ユニットＵ１は、図５（Ａ）に示すように、複数の伝熱素子１，１，…をそれらのベース部材２（ベース部材２ｃも含む、以下同じ）を離間して平行に配置すると共に、各ベース部材２の長手方向の両端から突出する熱媒体用のパイプ１６（パイプ１７も含む、以下同じ）に、ヘッダーパイプ２７を直角に接続している。
また、図５（Ｂ）は、複数の前記伝熱素子１を用いた異なる形態の伝熱ユニットＵ２の概略を示す。係る伝熱ユニットＵ２は、図５（Ｂ）に示すように、複数の伝熱素子１，１，…をそれらのベース部材２を隣接させて平行に配置し、各ベース部材２の長手方向の両端から突出し且つ隣接する熱媒体用のパイプ１６，１６間をほぼＵ字形の連絡パイプ２８を介して接続したものである。
以上のような伝熱ユニットＵ１，Ｕ２によれば、複数の前記伝熱素子１（１ａ）におけるパイプ１６（１７）に熱媒体を流通させることにより、これに密着したベース部材２（２ｃ）および蓋板１０を介して、これらに接触または近接する図示しない対象物を迅速に冷却または加熱することが可能となる。
【００３８】
図６（Ａ），（Ｂ）は、前記伝熱素子１の応用形態である伝熱素子１ｂおよびその製造方法を示す。図６（Ａ）に示すように、予め、前記同様のアルミニウム合金からなり、表面３に開口する断面矩形の蓋溝６と、係る蓋溝６の底面に開口し且つ互いに平行な一対の凹溝８，８とを有するベース部材２ｄを形成する。
次に、上記ベース部材２ｄの凹溝８，８に、前記同様のパイプ１６，１６を個別に挿入し（挿入工程）した後、上記蓋溝６にこれとほぼ同じ断面の蓋板１０を嵌合する（閉塞工程）。そして、上記蓋溝６の両側壁５，５と蓋板１０の両側面１３，１４との突き合わせ面に沿って、前記接合ツール２０を用いて摩擦攪拌接合前述した条件に沿ってを施す（接合工程）。その結果、図６（Ｂ）に示すように、上記突き合わせ面に沿って接合部Ｗ１，Ｗ２が形成され、これらにより各凹溝８のアール面７にパイプ１６の下半部を面接触で密着させ、且つ各パイプ１６の上端部に蓋板１０の底面１２が当接する伝熱素子１ｂを得ることができる。
【００３９】
図６（Ｃ），（Ｄ）は、前記伝熱素子１ａの応用形態である伝熱素子１ｃおよびその製造方法を示す。図６（Ｃ）に示すように、予め、前記同様のアルミニウム合金からなり、表面３に開口する断面矩形の蓋溝６と、係る蓋溝６の底面に開口し且つ互いに平行な一対の凹溝９，９とを有するベース部材２ｅを形成する。
次に、上記ベース部材２ｅの凹溝９，９に、前記同様のパイプ１７，１７を個別に挿入し（挿入工程）した後、上記蓋溝６にこれとほぼ同じ断面の蓋板１０を嵌合する（閉塞工程）。そして、上記蓋溝６の両側壁５，５と蓋板１０の両側面１３，１４との突き合わせ面に沿って、前記接合ツール２０を用いて摩擦攪拌接合前述した条件に沿ってを施す（接合工程）。その結果、図６（Ｄ）に示すように、上記突き合わせ面に沿って接合部Ｗ１，Ｗ２が個別に形成され、これらにより各凹溝９内にパイプ１６を面接触により密着させ、且つ各パイプ１７の上面に蓋板１０の底面１２が面接触する伝熱素子１ｃを得ることができる。
尚、ベース部材２ｄ，２ｅには、前記蓋溝６および凹溝８，９を長手方向に沿って一体に有するアルミニウム合金の押出形材を用いても良い。
【００４０】
図７（Ａ），（Ｂ）は、本発明の第２の伝熱素子１ｄとその製造方法を示す。
図７（Ａ）に示すように、前記同様のアルミニウム合金からなり、表面３に開口する断面矩形の蓋溝６と、係る蓋溝６の底面に開口する断面半円形の凹溝７とを有するベース部材２ｆを予め用意する。また、断面が上記蓋溝６と同じ長方形で且つ底面１２の中央に開口する断面半円形の凹溝１５を有する蓋板１０ａを用意する。上記凹溝７と凹溝１５とは、互いに同じ断面で且つ対向している。尚、ベース部材２ｆおよび蓋板１０ａには、押出形材を用いても良い。
【００４１】
図７（Ａ）中の矢印で示すように、ベース部材２ｆの凹溝７に、パイプ１６の下半部を挿入した後、ベース部材２ｆの蓋溝６に蓋板１０ａを嵌合すると同時に、その凹溝１５内に上記パイプ１６の上半部を挿入する（挿入・閉塞工程）。
次いで、ベース部材２ｆの蓋溝６の両側壁５，５と蓋板１０ａの両側面１３，１４との突き合わせ面に沿って、前記接合ツール２０を用いて摩擦攪拌接合前述した条件に沿ってを施す（接合工程）。その結果、図７（Ｂ）に示すように、上記突き合わせ面に沿って接合部Ｗ１，Ｗ２が形成されると共に、丸パイプ１６がその全周面でベース部材２ｆの凹溝７と蓋板１０ａの凹溝１５との内周面と密着した熱伝達性に優れた伝熱素子１ｄを、得ることができる。
【００４２】
図７（Ｃ）は、前記伝熱素子１ｄの応用形態である伝熱素子１ｅを示す。
図７（Ｃ）に示すように、ベース部材２ｇは、前記同様のアルミニウム合金からなり、表面３に開口する断面矩形の蓋溝６と、係る蓋溝６の底面に開口し且つ互いに平行な一対の凹溝７とを有し、蓋板１０ｂは、断面が上記蓋溝６と同じ長方形で且つ底面１２に開口する一対の凹溝１５を有する。上記凹溝７と凹溝１５も、互いに同じ断面で且つ対向している。尚、ベース部材２ｇおよび蓋板１０ｂにも、押出形材を用いても良い。
前記同様に、ベース部材２ｇの凹溝７，７に、パイプ１６の下半部を個別に挿入した後、ベース部材２ｇの蓋溝６に蓋板１０ｂを嵌合し、且つその凹溝１５，１５内に上記パイプ１６の上半部を個別に挿入する（挿入・閉塞工程）。
次いで、ベース部材２ｇの蓋溝６の両側壁５，５と蓋板１０ｂの両側面１３，１４との突き合わせ面に沿って、前記接合ツール２０を用いて摩擦攪拌接合前述した条件に沿ってを施す（接合工程）。その結果、図７（Ｃ）に示すように、上記突き合わせ面に沿って接合部Ｗ１，Ｗ２が形成されると共に、一対の丸パイプ１６がそれぞれの全周面でベース部材２ｇの凹溝７と蓋板１０ｂの凹溝１５との内周面と密着した熱伝達性に優れた伝熱素子１ｅを、得ることができる。
【００４３】
図８（Ａ），（Ｂ）は、本発明の第２の伝熱素子における異なる形態の伝熱素子１ｆとその製造方法を示す。
図８（Ａ）に示すように、前記同様のアルミニウム合金からなり、表面３に開口する断面矩形の蓋溝６と、係る蓋溝６の底面に開口する断面長方形の凹溝９ａとを有するベース部材２ｈを予め用意する。また、断面が上記蓋溝６と同じ長方形で且つ底面１２の中央に開口し且つ断面長方形の凹溝１５ａを有する蓋板１０ｃを用意する。上記凹溝９ａと凹溝１５ａとは、互いに同じ断面で且つ対向している。尚、ベース部材２ｈおよび蓋板１０ｃには、押出形材を用いても良い。
【００４４】
図８（Ａ）中の矢印で示すように、ベース部材２ｈの凹溝９ａに、断面が正方形のパイプ１７の下半部を挿入した後、ベース部材２ｈの蓋溝６に蓋板１０ｃを嵌合すると同時に、その凹溝１５ａ内に上記パイプ１７の上半部を挿入する（挿入・閉塞工程）。次いで、ベース部材２ｈの蓋溝６の両側壁５，５と蓋板１０ｃの両側面１３，１４との突き合わせ面に沿って、前記接合ツール２０を用いた摩擦攪拌接合を前述した条件によって施す（接合工程）。
その結果、図８（Ｂ）に示すように、上記突き合わせ面に沿よって接合部Ｗ１，Ｗ２が形成されると共に、パイプ１７がそのほぼ全周面でベース部材２ｈの凹溝９ａと蓋板１０ａの凹溝１５との内壁面と密着した熱伝達性に優れた伝熱素子１ｆを、得ることができる。
【００４５】
図８（Ｃ）は、前記伝熱素子１ｆの応用形態である伝熱素子１ｇを示す。
図８（Ｃ）に示すように、ベース部材２ｊは、前記同様のアルミニウム合金からなり、表面３に開口する断面矩形の蓋溝６と、係る蓋溝６の底面に開口し且つ互いに平行な一対の凹溝９ａとを有し、蓋板１０ｄは、断面が上記蓋溝６と同じ長方形で且つ底面１２に開口する一対の凹溝１５ａを有する。上記凹溝９ａと凹溝１５ａも、互いに同じ断面で且つ対向している。尚、ベース部材２ｊおよび蓋板１０ｄにも、押出形材を用いても良い。
前記同様に、ベース部材２ｊの各凹溝９ａに、パイプ１７の下半部を個別に挿入した後、ベース部材２ｊの蓋溝６に蓋板１０ｄを嵌合し、且つその凹溝１５ａ内に上記パイプ１７の上半部を個別に挿入する（挿入・閉塞工程）。
【００４６】
次いで、ベース部材２ｊの蓋溝６の両側壁５，５と蓋板１０ｄの両側面１３，１４との突き合わせ面に沿って、前記接合ツール２０を用いて摩擦攪拌接合前述した条件に沿ってを施す（接合工程）。その結果、図８（Ｃ）に示すように、上記突き合わせ面に沿って接合部Ｗ１，Ｗ２が形成されると共に、一対の角パイプ１７がそれぞれの全周面でベース部材２ｊの凹溝９ａと蓋板１０ｂの凹溝１５ａとの内壁面と密着した熱伝達性に優れた伝熱素子１ｇを、得ることができる。
尚、上記凹溝９ａと凹溝１５ａとは、互いに同じ断面でなく、幅のみが共通して、高さ（深さ）の相違する形態にしても良い。
【００４７】
本発明は、以上に説明した各形態や実施例に限定されるものではない。
例えば、前記熱媒体用のパイプは、断面が６角形や８角形の正多角形の形態とし、蓋板が平板の形態であって、上記パイプを挿入するベース部材の凹溝の下半部の断面を当該パイプの下半部の断面とほぼ同じ台形などにしても良い。
また、前記熱媒体用のパイプは、熱伝導率の高い銅または銅合金、あるいは比較的軽量で所要の強度を有するチタン合金などからなるものであっても良い。
更に、前記ベース部材の材質は、熱伝導率の高い銅または銅合金などからなるものとしても良い。
また、前記ベース部材２などの表面３および裏面４の少なくとも一方や、前記蓋板１０の上面１１であって、前記接合ツール２０の移動に支障のない位置に、熱交換促進用の凸条やフィンなどを突設しても良い。特に、ベース部材２などに、蓋溝６、凹溝８，９を押出成形により形成するアルミニウム合金の押出形材を用いる場合には、上記凸条やフィンなどを一体に突設できるため好適である。
【図面の簡単な説明】
【図１】（Ａ）は本発明の第１の伝熱素子における１形態の斜視図、（Ｂ）は（Ａ）中のＢ−Ｂ線に沿った矢視における断面図。
【図２】（Ａ）〜（Ｄ）は上記伝熱素子の製造工程を示す概略図。
【図３】（Ａ），（Ｂ），（Ｄ）は図２（Ｄ）に続く上記伝熱素子の製造工程を示す概略図、（Ｃ）は（Ｂ）中のＣ−Ｃに沿った矢視における断面図。
【図４】（Ａ）〜（Ｃ）は異なる形態の第１の伝熱素子またはその製造工程を示す概略図。
【図５】（Ａ），（Ｂ）は上記伝熱素子を複数用いた伝熱ユニットを示す概略図。
【図６】（Ａ），（Ｂ）は図１の伝熱素子の応用形態またはその製造工程を示す概略図、（Ｃ），（Ｄ）は図４の伝熱素子の応用形態またはその製造工程を示す概略図。
【図７】（Ａ），（Ｂ）は本発明の第２の伝熱素子における１形態またはその製造工程を示す概略図、（Ｃ）は上記伝熱素子の応用形態を示す概略図。
【図８】（Ａ），（Ｂ）は異なる形態の第２の伝熱素子またはその製造工程を示す概略図、（Ｃ）は上記伝熱素子の応用形態を示す概略図。
【符号の説明】
１，１ａ〜１ｄ…伝熱素子、２，２ｃ〜２ｊ…ベース部材、
３…………………表面、５…………………側壁、
６…………………蓋溝、７，８，９，９ａ…ベース部材の凹溝、
１０………………蓋板、１３，１４………側面、
１５，１５ａ……蓋板の凹溝、１６，１７………パイプ、
２０………………接合ツール、２２………………ツール本体、
２４………………ツール本体の底面、２６………………摩擦攪拌ピン、
Ｗ１，Ｗ２………接合部、Ｘ…………………凹溝の幅、
Ｙ…………………凹溝の深さ、Ｈ…………………突き合わせ面の深さ[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a heat transfer element used for, for example, a heat exchanger, a heating device or a cooling device, and a method for manufacturing the same.
[0002]
[Prior art]
The heat transfer element that is placed in contact with or in proximity to the object to be heat-exchanged, heated, or cooled, has a base member that is a main body thereof, and a pipe for circulating a heat medium such as, for example, cooling water is closely attached to the heat transfer element. Is required.
As a method of manufacturing such a heat transfer element, for example, a pipe made of stainless steel is penetrated and arranged in a predetermined cavity provided in a mold, and a molten metal of an aluminum alloy is cast and integrated into the cavity, for example. There is a wrapping method.
However, in the above cast-in method, a gap is generated between the obtained base member and the pipe because the aluminum alloy serving as the base member after casting is contracted when solidified. As a result, there has been a problem that heat transfer from the heat medium circulating in the pipe to the base member is reduced. In addition, since the production cost of the mold is high, there is also a problem that the cost increases when a relatively large heat transfer element is manufactured in a small amount.
[0003]
On the other hand, as a method for manufacturing a different heat transfer element, a stainless steel pipe or a heater having a stainless steel foil wound therearound is inserted into a groove formed on the surface of a base member made of an aluminum alloy, and There is a method of brazing a cover plate to the surface of the base member so as to cover the opening of the groove.
However, in the method using brazing, for example, when a heater is inserted into the groove, the heat generated by the heating lowers the bonding strength of the brazing material, or the lid plate is loosened due to such a situation, and the heat between the heater and the base member is reduced. There was a problem that the transmissibility was reduced. In addition, among the aluminum alloys used as the base member, there is also a problem that brazing cannot be performed with a 2000 or 5000 series alloy having high high-temperature strength.
[0004]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION The present invention solves the above-described problems in the related art, and has a heat transfer element excellent in heat transfer property in which a pipe or heater for a heat medium and a base member containing the same are in close contact with each other. It is another object of the present invention to provide a method of manufacturing a heat transfer element that can be manufactured at a high speed.
[0005]
Means for Solving the Problems and Effects of the Invention
In order to solve the above-mentioned problems, the present invention is to insert a heat medium pipe or the like into a concave groove or the like formed on a bottom surface of a lid groove formed in a base member so as to be in close contact therewith, and to cover the lid groove with substantially the same cross section. In addition to fitting the plates, the lid plate and the base member are friction stir welded to be integrated in a solid state.
That is, the first heat transfer element (Claim 1) of the present invention includes a base member having a lid groove having a rectangular cross section opening on the surface and a concave groove opening on the bottom surface of the lid groove, and a concave of the base material. A pipe or heater for a heat medium inserted into the groove, and a lid plate fitted in the lid groove of the base material, each of the side walls and both side surfaces of the lid plate in the lid groove of the base material A joint portion formed by friction stir welding is formed along the butt surface.
Further, a second heat transfer element of the present invention is a base material having a lid groove having a rectangular cross section opening on the surface and a concave groove opening on the bottom surface of the lid groove, and a lid of the base material. A lid plate having a concave groove fitted into the groove and opening on the bottom surface, a pipe or a heater for a heat medium inserted across the concave groove of the base material and the concave groove of the lid plate, A joint portion formed by friction stir welding is formed along each abutting surface between both side walls of the lid groove of the base material and both side surfaces of the lid plate.
[0006]
According to these, since the base member and the lid plate are joined via the joining portion by friction stir welding in which both metal materials are integrated in a solid state, the concave groove opening on the bottom surface of the lid groove Or between the groove and the groove of the lid plate, it is possible to prevent a decrease in strength at the joint portion due to heat from the inserted pipe or heater. Moreover, since the lid plate and the base member are pressurized by the bonding seal described later during the friction stir welding, in the first heat transfer element, a pipe or the like that is in contact with or pressed against the bottom surface of the lid plate is It comes into close contact with the concave groove of the base member while making surface contact. On the other hand, in the second heat transfer element, the pipe and the like are in close contact with each other on the entire peripheral surface of the concave groove of the base member and the concave groove located on the bottom surface of the cover plate. Therefore, it is possible to efficiently transfer heat energy from a heat medium or a heater circulating in the pipe or the like to an object to be transferred via the base member.
The materials of the base member and the cover plate are not particularly limited, but an aluminum alloy having particularly high thermal conductivity and excellent workability is recommended. When the base member and the cover plate are made of an aluminum alloy, the pipe is preferably a stainless steel pipe having a higher melting point and a higher rigidity than the aluminum alloy, and the heater is made of stainless steel foil around a known heating wire. Wound form is recommended. Further, the base member may be an extruded profile of an aluminum alloy capable of integrally forming the lid groove and the concave groove, and the lid plate used for the second heat transfer element may be a similar extruded profile having the concave groove.
[0007]
On the other hand, the method of manufacturing a heat transfer element according to the present invention (claim 3) is characterized in that a concave groove provided on the bottom surface of a lid groove having a rectangular cross section opened on the surface of the base member or the concave groove of the base material and the lid are formed. An insertion step of inserting a pipe or a heater for a heat medium over a concave groove provided on the bottom surface of the lid plate fitted into the groove, and fitting the lid plate having substantially the same cross section into the lid groove of the base member. And a joining step of performing friction stir welding along each abutting surface between both side walls of the lid groove of the base material and both side surfaces of the lid plate.
According to this, the base member and the lid plate can be firmly joined via the joining part by friction stir welding that integrates both metal materials in a solid state. Moreover, in a mode in which the bottom surface of the cover plate has no concave groove, the base member and the cover plate are joined while being pressed, so that the bottom surface of the cover plate contacts or presses against a pipe or a heater, and the pipe or the like and the base member are connected. The concave groove can be brought into close contact with a wide surface. Further, in the form in which the bottom surface of the lid plate also has a concave groove, a pipe or the like can be brought into close contact with the concave groove of the base member and the lid plate in the entire peripheral surface. Therefore, it is possible to efficiently and reliably manufacture a heat transfer element having a joint portion which has excellent heat transferability and can maintain high strength even by heat energy from a pipe, a heater, or the like.
[0008]
In addition, the material of the base member and the lid plate includes the case where both are made of the same kind of aluminum alloy and the case where they are made of a combination of different kinds of aluminum alloys because the friction stir welding can be applied between different kinds of metals. It is. Further, when the base member and the lid plate are made of aluminum alloys, since the joining temperature at the time of the friction stir welding is in a temperature range of 500 ° C. or less, the heater of the heater previously inserted into the concave groove of the base member or the lid plate is used. Deterioration of characteristics can also be prevented.
[0009]
Further, according to the present invention, the cross-sectional shape of at least the lower half of the concave groove of the base plate is the same as or substantially similar to the cross-sectional shape of the lower half of the pipe or heater. A method for manufacturing a thermal element (claim 4) is also included. According to this, the contact area between the pipe or the heater and the inner wall of the concave groove of the base plate or the lid plate without the concave groove can be brought into close contact with the entire peripheral surface of the pipe or 50% or more thereof. Therefore, the thermal energy from the pipe or the heater can be reliably transmitted to the base member. When the cross section of the pipe or heater is circular and the bottom surface of the lid plate is flat, the lower half of the concave groove of the base plate has a semicircular cross section, and the cross section of the pipe or the like is a hexagonal or higher regular polygon. When the bottom surface of the lid plate is flat, the lower half of the groove has a rectangular or trapezoidal shape, and the lower half of the cross section makes surface contact with the inner wall of the groove. Further, when the cross section of a pipe or the like is a square, by inserting into a concave groove of a cross-section base member having a substantially same square shape as the pipe, the bottom surface without a concave groove in the entire peripheral surface of the pipe and the concave plate in the cover plate is formed. Surface contact is possible. On the other hand, in a form in which the concave groove is located on the bottom surface of the lid plate, the concave groove of the lid plate and the concave groove of the base plate have the same symmetrical and semicircular or rectangular cross section.
[0010]
Further, in the present invention, the depth of the groove of the base plate in a form in which there is no groove on the bottom surface of the lid plate is an outer diameter of the pipe or the heater or a range of less than 1.2 times the outer diameter. The method for manufacturing a heat transfer element described in (5) is also included. According to this, the peripheral surface of at least the lower half of the pipe or the heater can be securely brought into close contact with the inner wall of the concave groove of the base plate by surface contact.
If the depth of the groove of the base plate is smaller than the outer diameter of the pipe or the like, the entire cross section of the pipe or the like cannot be inserted into the groove. On the other hand, when the depth of the groove is 1.2 times or more the outer diameter of the pipe or the like, the pressing by the cover plate is stopped, and a gap is generated between the pipe and the inner wall of the groove. Therefore, such a range is excluded.
[0011]
The present invention also includes a method for manufacturing a heat transfer element, wherein the width of the concave groove is within an outer diameter of the pipe or the heater or 1.1 times the outer diameter of the pipe or the heater (claim 6).
This also ensures that at least the peripheral surface or the entire peripheral surface of the lower half portion of the pipe or heater is brought into close contact with the concave groove of the base member or the concave groove of the bottom surface of the lid plate by surface contact. If the width of the concave groove of the base member or the cover plate is smaller than the outer diameter of the pipe or the like, a pipe or the like cannot be inserted into the concave groove, and the width of the concave groove is 1.1 times the outer diameter of the pipe or the like. If it exceeds, a gap is generated between the pipe or the like and the inner wall of the concave groove. Therefore, such a range is excluded. Further, the above-described depth and width ranges of the concave groove are particularly suitable when the base member and the cover plate are made of an aluminum alloy, and the pipe or the like is made of a highly rigid stainless steel pipe.
[0012]
In addition, according to the present invention, a welding tool used for friction stir welding in the welding step includes a tool main body and a friction stir pin that coaxially hangs from a center portion of a bottom surface of the tool body, and the axial length of the friction stir pin is long. The method also includes a method of manufacturing a heat transfer element having a depth in the range from the depth of the butted surface to 60% or more thereof.
According to this, while holding the surface near the butt surface of the base member and the lid plate with the tool body of the joining tool that rotates at high speed, the friction stir pin that rotates at a high speed with the tool body and enters near the butt surface, The metal material forming the member and the cover plate can be fluidized and stirred in a solid state by frictional heat. For this reason, it is possible to firmly join the lid plate in a state fitted in the lid groove of the base member. In addition, a pipe or the like approaching the bottom surface of the cover plate having no groove can be pushed into the groove of the base member, or can be brought into surface contact with the entire peripheral surface of the groove of the base member and the groove of the cover plate. . Therefore, the peripheral surface of the pipe or the like and the inner wall of the concave groove can be surely brought into close contact with each other by surface contact.
If the axial length of the friction stir pin is less than 60% of the depth of the butted surface, the depth of the joint formed along the butted surface becomes nearly half of the above depth, Insufficient strength can result. Further, if the axial length of the friction stir pin is longer than the depth of the abutting surface, the fluidized metal material enters between the lid groove and the lid plate, and the strength of the joint is insufficient. Was excluded. Further, the depth of the abutting surface is a distance obtained by subtracting the pushing amount along the axial direction of the joining tool.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings.
FIG. 1A is a perspective view showing a heat transfer element 1 which is one mode of a first heat transfer element according to the present invention, and FIG. 1B is a vertical sectional view of the heat transfer element 1. .
As shown in FIGS. 1A and 1B, the heat transfer element 1 has a thick plate-shaped base member 2 having a front surface 3 and a back surface 4, an opening in the front surface 3 of the base member 2, and a rectangular cross section. A cover plate 10 is fitted into the (rectangular) cover groove 6, and a heat medium pipe 16 is inserted into the concave groove 8 opened on the bottom surface of the cover groove 6. The base member 2 is made of, for example, an aluminum alloy (JIS: A6061). As shown in FIG. 1A, a cover groove 6 is formed along a front-rear (longitudinal) direction of the drawing, and a groove 8 is formed at the center of the bottom surface. Are formed. The concave groove 8 has a round surface (concave groove) 7 whose lower half is a semicircular cross section, and a cross section of the upper half near the lid groove 6 is a rectangle having the same width as the diameter of the round surface 7. is there.
[0014]
The lid plate 10 is also made of the same aluminum alloy as described above, and as shown in FIGS. 1A and 1B, an upper surface 11 which forms a rectangular (rectangular) cross section substantially the same as the cross section of the lid groove 6 of the base member 2. , A bottom surface 12 and left and right side surfaces 13 and 14.
Further, the pipe 16 is made of, for example, stainless steel (JIS: SUS304). As shown in FIG. 1 (B), the lower half of the cross section is substantially the same as the round surface 7 of the concave groove 8 in the base member 2. It has a semicircular shape. Incidentally, the pipe 16 has an outer diameter of 3 mm and a thickness of 0.5 mm, and has a hollow portion 18 having a circular cross section therein. A heat medium such as cooling water, cooling gas, high-temperature liquid, or high-temperature gas circulates and flows through the hollow portion 18.
[0015]
As will be described later, the depth of the concave groove 8 of the base member 2 is in the range of the same depth as the outer diameter of the pipe 16 or less than 1.2 times the outer diameter of the pipe 16. The width of the upper half except for the round surface 7 is in the range of the same width as the outer diameter of the pipe 16 or a depth of 1.1 times or less of the outer diameter. Therefore, the peripheral surface of the lower half portion of the pipe 16 is in surface contact with the round surface 7 of the concave groove 8.
As shown in FIGS. 1A and 1B, abutting surfaces of the

side walls

5, 5 of the lid groove 6 of the base member 2 and the side surfaces 13, 14 of the lid plate 10 fitted in the lid groove 6. Along, joints W1 and W2 by friction stir welding are individually formed. The joining portions W1 and W2 are obtained by integrating the metal materials of the base member 2 and the cover plate 10 by using a joining tool described later while fluidizing in a solid state by frictional heat while stirring. Incidentally, the depth of the joints W1 and W2 is about 80% of the depth of the butted surface.
[0016]
According to the heat transfer element 1 as described above, the base member 2 and the cover plate 10 are joined via the joints W1 and W2 by friction stir welding in which both metal materials are integrated in a solid state. I have. For this reason, it is possible to prevent a decrease in the strength of the joints W1 and W2 due to heat from the pipe 16 inserted into the concave groove 8 opened on the bottom surface of the lid groove 6. In addition, since the lid plate 10 and the base member 2 are pressed against the bottom surface (shoulder) of the tool body of the welding tool described later during friction stir welding, the lid plate 10 and the base member 2 come into contact with or are pressed against the bottom surface 12 of the lid plate 10. The pipe 16 is in close contact with the round surface 7 of the groove 8 while making surface contact. Therefore, heat energy from the heat medium circulating in the pipe 8 can be efficiently transmitted to the object located near the heat medium via the base member 2.
In particular, when the depth and width of the groove 8 are the same as or slightly smaller than the outer diameter of the pipe 16, good adhesion between the pipe 16 and the inner wall of the groove 8 can be obtained.
[0017]
Next, a method for manufacturing the heat transfer element 1 will be described with reference to FIGS.
FIG. 2A shows a cross section of a thick plate 2a having a front surface 3 and a back surface 4 and made of the same aluminum alloy as described above. The thick plate 2a has a rectangular shape whose longitudinal direction is the front-rear direction shown in plan view. A known spot facing process is performed using an end mill cutter or the like along the vicinity of the longitudinal center of the surface 3 of the thick plate 2a. As a result, as shown in FIG. 2 (B), a thick plate 2b having a lid groove 6 having a rectangular cross section, a rectangular cross section, and left and

right side walls

5, 5 is formed.
After counterboring the central portion of the bottom surface of the lid groove 6 of the thick plate 2b with a predetermined width in the longitudinal direction, the lower side is further cut out into a semicircular cross section by cutting. As a result, as shown in FIG. 2 (C), the base member 2 having the above-described lid groove 6 and the concave groove 8 opening at the center of the bottom surface thereof along the longitudinal direction is formed. The concave groove 8 has an upper surface having a rectangular cross section and a lower half having a semicircular cross section.
[0018]
The base member 2 may be made of an extruded aluminum alloy in which the lid groove 6 and the concave groove 8 are formed integrally in advance in the longitudinal direction.
As shown in FIG. 2C, the depth (depth of the deepest portion) Y of the concave groove 8 is set to be equal to or less than 1.2 times the outer diameter of the heat medium pipe 16 described below. At the same time, the width X of the concave groove 8 is in the range from the same as the outer diameter of the pipe 16 to 1.1 times or less.
Next, as shown in FIG. 2D, a heat medium pipe 16 made of the same stainless steel as described above is inserted into the groove 8 (insertion step). The peripheral surface of the lower half of the pipe 16 in which the hollow portion 18 is provided is in surface contact with the round surface 7 forming the lower half of the concave groove 8 over its entire length. The upper end of the pipe 16 is located near the opening of the groove 8 and at the same level as the bottom surface of the lid groove 6 or at a position slightly lower than the bottom surface.
[0019]
Further, as shown in FIG. 3A, the upper surface 11, the lower surface 12, and the left and right side surfaces 13 are made of the same aluminum alloy as described above in the lid groove 6 of the base member 2 in which the pipe 16 is inserted into the concave groove 8. , 14 are fitted with a lid plate 10 having a rectangular cross section substantially the same as the cross section of the lid groove 6 (closing step). At this time, the upper end of the pipe 16 is in line contact with or near the center of the bottom surface 12 of the cover plate 10, and the upper surface 11 of the cover plate 10 is flush with the left and right surfaces 3, 3 of the base member 2. Become.
Next, as shown in FIGS. 3B and 3C, along two rows of abutting surfaces of the

side walls

5 and 5 of the cover groove 6 of the base member 2 and the side surfaces 13 and 14 of the cover plate 10, Perform friction stir welding (joining step). The joining tool 20 shown is used for such joining.
[0020]
That is, the joining tool 20 is made of, for example, tool steel, and as shown in FIGS. 3B and 3C, a cylindrical tool main body 22 and a friction stir pin hanging coaxially from the center of the bottom surface 24 thereof. 26. In addition, a plurality of small grooves (not shown) or thread grooves along the radial direction may be formed on the peripheral surface of the stirring pin 26 along the axial direction.
Incidentally, the diameter of the tool main body 22 is 6 to 20 mm, the length of the friction stir pin 26 is 3 to 10 mm, and the diameter thereof is 2 to 8 mm. The rotational speed of the friction stir tool 20 is 500 to 15000 rpm, the feed speed is 0.05 to 2 m / min, and the pushing force applied in the axial direction of the tool 20 is about 1 kN to 20 kN.
[0021]
As shown in FIGS. 3B and 3C, in a state where the base material 2 and the cover plate 10 are restrained by a jig (not shown), the left side wall 5 in the cover groove 6 and the side surface 13 of the cover plate 10 abut. A high-speed rotating joining tool 20 is pushed along the surface. At this time, the bottom surface 24 of the tool main body 22 is parallel to the surface 3 of the base member 2 and the upper surface 11 of the cover plate 10. The axial length of the friction stir pin 26 is, as shown in FIG. 3B, in a range not more than the depth H of the butted surface and not less than 60% thereof.
As shown in FIGS. 3B and 3C, the bottom surface of the friction stir pin 26 in the friction stir tool 20 reaches slightly below the abutting surface. In this state, the aluminum alloy material of the base member 2 and the cover plate 10 located therearound is heated by frictional heat by the friction stir pin 26 which rotates at high speed, and is plasticized and fluidized (mass transfer) in a semi-solid state. I do. If there are small grooves along the axial direction or screw grooves along the radial direction on the peripheral surface of the friction stir pin 26, the stirring of the aluminum alloy material can be further activated.
[0022]
As shown in FIGS. 3 (B) and 3 (C), the trace of the rotation and passage of the friction stir tool 20 is formed along the abutting surface between the side wall 5 of the lid groove 6 and the side surface 13 of the lid plate 10. The joint W1 in which the plasticized and fluidized aluminum alloy material is solidified is formed. When the alloy material has sufficiently flowed plastically, there is no minute tunnel defect, which is a large number of holes, in the inside of the joint W1. The surface wa of the joint W1 has fine irregularities in a wavy shape following the periphery of the bottom surface 24 of the tool body 22, and is slightly recessed from the surface 3 or the like due to the amount of pushing of the tool body 22. I have. Subsequently, the same friction stir welding as described above is performed using the welding tool 20 along the abutting surface between the right side wall 5 in the lid groove 6 and the side surface 14 of the lid plate 10.
[0023]
As a result, as shown in FIG. 3D, joints W1 and W2 are formed along the abutting surfaces of the

side walls

5 and 5 of the cover groove 6 and the side surfaces 13 and 14 of the cover plate 10, respectively. As a result, the cover plate 10 is tightly fitted into the cover groove 6 of the base member 2, and the bottom surface 12 of the cover plate 10 is inserted into the concave groove 8 in advance, and the upper end of the pipe 16 is in surface contact with the lower half. A heat transfer element 1 abutting or very close is obtained.
According to the method for manufacturing the heat transfer element 1 as described above, the heat transfer element 1 having the junctions W1 and W2 which is excellent in heat transferability and can maintain high strength even by the heat energy from the pipe 16 is efficiently and reliably provided. Can be manufactured. Instead of the pipe 16, for example, a heater having a circular cross section in which a stainless steel foil is wound around a heating wire or the like may be inserted into the concave groove 8 of the base member 2.
[0024]
FIG. 4 relates to a different form of the heat transfer element 1a and its manufacturing method.
First, the surface 3 of a thick plate made of the same aluminum alloy as described above is counterbored or cut to form a lid groove 6 having a rectangular cross section (rectangle) opening on the surface 3 as shown in FIG. , A base member 2c having an opening at the center of the bottom surface and a concave groove 9 having a square cross section is formed. The base member 2c may be made of an extruded aluminum alloy having the lid groove 6 and the concave groove 9 integrally in the longitudinal direction in advance.
Next, a pipe 17 for a heat medium having a square cross section having substantially the same vertical and horizontal dimensions as its depth and width is inserted into the concave groove 9 (insertion step). The pipe 17 is made of the same stainless steel as that described above, has a hollow portion 19 having a cross section similar to the outer shape, and is in surface contact with the bottom surface of the concave groove 9 and the left and right side walls.
[0025]
Next, as shown in FIG. 4 (B), a rectangular section made of the same aluminum alloy as described above is formed in the lid groove 6 of the base member 2c in which the pipe 17 is inserted into the concave groove 9, and is substantially the same as the cross section of the lid groove 6. (Closed step). At this time, the upper surface of the pipe 17 comes into surface contact with or extremely near the center of the bottom surface 12 of the lid plate 10, and the upper surface 11 of the lid plate 10 is flush with the surfaces 3, 3 of the base member 2c. Become.
Then, along the pair of abutting surfaces of the left and

right side walls

5 and 5 in the cover groove 6 and the side surfaces 13 and 14 of the cover plate 10, the same friction stir welding is individually performed using the similar welding tool 20. (Joining step).
[0026]
As a result, as shown in FIG. 4C, joints W1 and W2 are formed along the pair of butted surfaces, whereby the cover plate 10 is tightly fitted in the cover groove 6 of the base member 2c, The heat transfer element 1a in which the bottom surface 12 of the cover plate 10 is inserted into the concave groove 9 in advance and faces the surface of the pipe 17 which is in surface contact with or in close proximity to the pipe 17 is obtained.
As shown in FIG. 4 (C), the heat transfer element 1a has a pipe 17 having a square (square) cross section inserted into the groove 9 having substantially the same or similar cross section by surface contact, and a lid is provided on the upper surface of the pipe 17. Since the bottom surface 12 of the plate 10 is in surface contact or close proximity, heat transfer characteristics are further improved. Further, according to the above-described method for manufacturing heat transfer element 1a, heat transfer element having junctions W1 and W2 that can maintain high strength between base member 2c and cover plate 10 even by thermal energy from pipe 17. 1a can be efficiently and reliably manufactured.
[0027]
【Example】
Here, specific examples of the heat transfer element 1 of the present invention will be described.
1 (A), (B) and 4 (C), the longitudinal direction is 300 mm, the width of the front surface 3 and the back surface 4 is 30 mm, the thickness is 20 mm, and the lid is made of aluminum alloy (JIS: A6061). For the groove 6, two

base members

2 and 2c each having a depth of 5 mm and a width of 10 mm were prepared. The concave groove 8 of the base member 2 has a depth (deepest part) Y: 3 mm × width X: 3 mm, and a lower half of the cross section is the semicircular round surface 7. The concave groove 9 of the base member 2c has a square cross section of a depth Y: 3 mm × a width X: 3 mm.
[0028]
A heat medium pipe 16 made of stainless steel (JIS: SUS304) and having a total length of 340 mm, an outer diameter of 3 mm and a thickness of 0.5 mm is inserted into the concave groove 8 of the base member 2 with both ends protruding. did. On the other hand, a pipe 17 of the same material and having a square section with a total length of 340 mm × length: 3 mm × width: 3 mm × wall thickness: 0.5 mm was inserted into the concave groove 9 of the base member 2 c with both ends protruding. The lid plate 10 made of the same aluminum alloy as described above and having a total length of 300 mm, a width of 9.8 mm and a thickness of 5 mm was individually fitted into the lid grooves 6 of the

base members

2 and 2c. In a state where the

base members

2 and 2c including the cover plate 10 are restrained, friction stir welding is performed along a pair of abutting surfaces of both

side walls

5 and 5 of the cover groove 6 and both side surfaces 13 and 14 of the cover plate 10. Were joined individually.
[0029]
The welding tool 20 used for this is made of tool steel (SKD61), the tool body 22 has a diameter of 15 mm, and the friction stir pin 26 has a diameter of 5 mm and a length of 3.8 mm. The welding tool 20 is rotated and moved along the abutting surface under the same conditions of a rotational speed of 1400 rpm, a moving speed of 300 mm / min, and an axial depth of penetration (distance) of 0.2 mm, and bonding. The parts W1 and W2 were individually formed.
The heat transfer element 1 using the base member 2 was Example 1, and the heat transfer element 1a using the base member 2c was Example 2. These were cut at four locations in the longitudinal direction and visually inspected to determine the presence or absence of a tunnel defect or the like at the joints W1 and W2 and the presence of gaps between the pipe 16 and the

grooves

8, 9 and the cover plate 10. Table 1 shows the results.
[0030]
[Table 1]

[0031]
According to Table 1, no tunnel defect or the like was found at the junctions W1 and W2 of the heat transfer elements 1 and 1a of Examples 1 and 2. Further, there is no gap between the concave groove 8 of the first embodiment and the lower half of the pipe 16, and between the concave groove 9 including the bottom surface 12 of the cover plate 10 of the second embodiment and the pipe 17, It was found that the sample had good adhesion without gaps.
Next, ten base members 2 which were the same as those in the first embodiment were prepared, and as shown in Table 2, the depth (the deepest portion) Y and the width X of the concave grooves 8 were changed to obtain the same heat medium as the above. Pipes 16 were individually inserted. The friction stir welding is individually performed along the abutting surfaces of the

side walls

5 and 5 of the cover groove 6 and the side surfaces 13 and 14 of the cover plate 10 using the same welding tool 20 and under the same conditions as above. I went to.
The obtained 10 heat transfer elements (1) were cut and observed in the same manner as described above, and the presence or absence of defects or the like at the joints W1 and W2 and the presence or absence of gaps between the pipe 16 and the concave groove 8 and the cover plate 10 were determined. Examined. Table 2 also shows the results.
[0032]
[Table 2]

[0033]
According to Table 2, in Comparative Example 1 in which the depth Y of the concave groove 8 is smaller (shallower) than the outer diameter of the pipe 16, a tunnel defect occurs at the joints W1 and W2 due to the lifting of the cover plate 10, and A gap was formed between the groove 16 and the round surface of the concave groove 8. In Comparative Example 2 in which the depth Y of the groove 8 is 1.2 times the outer diameter of the pipe 16, the center of the cover plate 10 is dented and the side surfaces 13 and 14 are lifted by the pressing of the joining tool 20. In addition, defects due to the shortage of the aluminum alloy material occurred in the joints W1 and W2, and the above-described gap also occurred.
Further, in Comparative Examples 3 to 5 in which the width X of the concave groove 8 exceeds 1.1 times the outer diameter of the pipe 16, the lid plate 10 bends and deforms as described above. Defects occurred due to shortage and the above gaps also occurred.
On the other hand, the depth Y of the concave groove 8 is equal to or less than 1.2 times the outer diameter of the pipe 16, and the width X of the concave groove 8 is equal to or less than 1.1 times the outer diameter of the pipe 16. In Examples 3 to 7, the junctions W1 and W2 did not have a tunnel defect or the like, and the round surface 7 of the concave groove 8 and the lower half portion of the pipe 16 were in good contact with no gap.
[0034]
Further, seven sets of the base member 2, the cover plate 10, and the pipe 16 for the heat medium, which were the same as those of the first embodiment, were prepared and inserted and fitted in the same manner as described above.
As shown in Table 3, the axial length of the friction stir pin 26 in the welding tool 20 was changed so that the pushing amount (distance) of the tool main body 22 was constant, and both side walls of the seven sets of lid grooves 6 were formed. Friction stir welding was individually performed along the abutting surfaces of the side surfaces 5 and 5 and the side surfaces 13 and 14 of the lid plate 10 under the same conditions as described above, including the amount of pushing.
The obtained seven heat transfer elements (1) were cut and visually inspected in the same manner as described above, and the presence or absence of defects at the joints W1 and W2 and the presence or absence of a gap between the concave groove 8 and the pipe 16 were examined. Table 3 also shows the results.
[0035]
[Table 3]

[0036]
According to Table 3, in Comparative Example 6 in which the length of the friction stir pin 26 is longer than the depth H of the abutting surface (the depth of the lid groove 6 excluding the pushing amount), the plasticized fluidized aluminum alloy material is used. Since the cover member 10 is inserted between the cover groove 6 and the cover plate 10, a gap is formed between the base member 2 and the pipe 16 and the cover plate 10.
Further, in Comparative Example 7 in which the length of the friction stir pin 26 is less than 60% of the depth H of the abutting surface, the composition flow of the material, the pressurization by the welding tool 20 and the plastic flow of the aluminum alloy material are insufficient. Since the joining strength of the joining portions W1 and W2 is low, a gap is generated between the pipe 16 and the bottom surface 12 of the cover plate 10.
On the other hand, in Examples 8 to 12 in which the length of the friction stir pin 26 was equal to or more than 60% of the depth H of the abutting surface, the joints W1 and W2 had no defects, and the pipe 16 and the groove 8 and the upper end of the pipe 16 and the bottom surface 12 of the cover plate 10 were in good contact with no gap.
The effects of the present invention were supported by the heat transfer elements 1 of Examples 1 to 12 described above.
[0037]
FIG. 5A schematically shows a heat transfer unit U1 using a plurality of the heat transfer elements 1 (including the heat transfer element 1a, the same applies hereinafter). As shown in FIG. 5A, the heat transfer unit U1 has a plurality of

heat transfer elements

1, 1,... Arranged in parallel with their base members 2 (including the base member 2c, the same applies hereinafter). At the same time, a header pipe 27 is connected at right angles to a heat medium pipe 16 (including the pipe 17, the same applies hereinafter) protruding from both ends in the longitudinal direction of each base member 2.
FIG. 5B schematically shows a heat transfer unit U <b> 2 in a different form using a plurality of the heat transfer elements 1. The heat transfer unit U2 has a plurality of

heat transfer elements

1, 1,... Arranged in parallel with their base members 2 adjacent to each other as shown in FIG. The pipes 16 projecting from both ends and adjacent to each other for the heat medium are connected via a substantially U-shaped connecting pipe 28.
According to the heat transfer units U1 and U2 as described above, the heat medium flows through the pipes 16 (17) in the plurality of heat transfer elements 1 (1a), so that the base members 2 (2c) and Through the cover plate 10, it is possible to quickly cool or heat an object (not shown) in contact with or in proximity to them.
[0038]
FIGS. 6A and 6B show a heat transfer element 1 b which is an application of the heat transfer element 1 and a method of manufacturing the same. As shown in FIG. 6A, a lid groove 6 made of the same aluminum alloy as described above and having a rectangular cross section opened on the surface 3 and a pair of concave grooves opened on the bottom surface of the lid groove 6 and parallel to each other. Then, a base member 2d having 8, 8 is formed.
Next, the

same pipes

16 and 16 as described above are individually inserted into the

concave grooves

8 and 8 of the base member 2d (insertion step), and a cover plate 10 having substantially the same cross section as this is fitted into the cover groove 6. (Blocking step). Then, along the abutting surfaces of the

side walls

5 and 5 of the cover groove 6 and the side surfaces 13 and 14 of the cover plate 10, friction stir welding is performed using the welding tool 20 in accordance with the above-described conditions (joining). Process). As a result, as shown in FIG. 6 (B), joints W1 and W2 are formed along the abutting surface, and the lower half of the pipe 16 is brought into close contact with the round surface 7 of each groove 8 by surface contact. Then, the heat transfer element 1b in which the bottom surface 12 of the lid plate 10 abuts on the upper end of each pipe 16 can be obtained.
[0039]
FIGS. 6C and 6D show a heat transfer element 1c which is an application of the heat transfer element 1a and a method of manufacturing the same. As shown in FIG. 6C, a lid groove 6 made of the same aluminum alloy as described above and having a rectangular cross section opened on the surface 3 and a pair of concave grooves opened on the bottom surface of the lid groove 6 and parallel to each other. The base member 2e having the

components

9 and 9 is formed.
Next, the

same pipes

17, 17 as described above are individually inserted into the

concave grooves

9, 9 of the base member 2e (insertion step), and a lid plate 10 having substantially the same cross section as this is fitted into the lid groove 6. (Blocking step). Then, along the abutting surfaces of the

side walls

5 and 5 of the cover groove 6 and the side surfaces 13 and 14 of the cover plate 10, friction stir welding is performed using the welding tool 20 in accordance with the above-described conditions (joining). Process). As a result, as shown in FIG. 6 (D), joints W1 and W2 are individually formed along the abutting surfaces, whereby the pipes 16 are brought into close contact with the respective grooves 9 by surface contact, and The heat transfer element 1c in which the bottom surface 12 of the cover plate 10 is in surface contact with the upper surface of 17 can be obtained.
The

base members

2d and 2e may be made of an extruded aluminum alloy having the lid groove 6 and the

concave grooves

8 and 9 integrally along the longitudinal direction.
[0040]
FIGS. 7A and 7B show a second heat transfer element 1d of the present invention and a method of manufacturing the same.
As shown in FIG. 7A, the cover groove 6 is made of the same aluminum alloy as described above and has a rectangular cross section opened on the surface 3 and a semicircular concave groove 7 opened on the bottom surface of the cover groove 6. A base member 2f is prepared in advance. In addition, a lid plate 10 a having a rectangular cross section, which is the same as the lid groove 6, and having a semicircular concave groove 15 opening at the center of the bottom surface 12 is prepared. The groove 7 and the groove 15 have the same cross section and face each other. In addition, an extruded shape member may be used for the base member 2f and the lid plate 10a.
[0041]
As shown by the arrow in FIG. 7A, after inserting the lower half of the pipe 16 into the concave groove 7 of the base member 2f, the cover plate 10a is fitted into the cover groove 6 of the base member 2f, The upper half of the pipe 16 is inserted into the groove 15 (insertion / closing step).
Next, along the abutting surfaces of the

side walls

5, 5 of the lid groove 6 of the base member 2f and the side surfaces 13, 14 of the lid plate 10a, friction stir welding is performed using the welding tool 20 according to the above-described conditions. (Joining step). As a result, as shown in FIG. 7B, the joints W1 and W2 are formed along the abutting surface, and the round pipe 16 is formed on the entire peripheral surface thereof with the concave groove 7 of the base member 2f and the cover plate 10a. A heat transfer element 1d having excellent heat transfer properties, which is in intimate contact with the inner peripheral surface of the concave groove 15 can be obtained.
[0042]
FIG. 7C shows a heat transfer element 1e which is an application of the heat transfer element 1d.
As shown in FIG. 7 (C), the base member 2g is made of the same aluminum alloy as described above, and has a lid groove 6 having a rectangular cross section opened on the front surface 3 and a pair of parallel holes opened on the bottom surface of the lid groove 6 and parallel to each other. The lid plate 10 b has a pair of concave grooves 15 which are rectangular in cross section as in the lid groove 6 and open to the bottom surface 12. The

grooves

7 and 15 also have the same cross section and face each other. Note that an extruded profile may be used for the base member 2g and the lid plate 10b.
Similarly, after individually inserting the lower halves of the pipes 16 into the

grooves

7, 7 of the base member 2g, the cover plate 10b is fitted into the cover groove 6 of the base member 2g, and the

grooves

15, 7 are formed. The upper half of the pipe 16 is individually inserted into the pipe 15 (insertion / closing step).
Next, along the abutting surfaces of the

side walls

5, 5 of the lid groove 6 of the base member 2g and the both side surfaces 13, 14 of the lid plate 10b, friction stir welding is performed using the welding tool 20 according to the above-described conditions. (Joining step). As a result, as shown in FIG. 7 (C), the joints W1 and W2 are formed along the abutting surface, and the pair of round pipes 16 are formed with the concave grooves 7 of the base member 2g on the entire circumferential surface. It is possible to obtain a heat transfer element 1e having excellent heat transfer properties, which is in close contact with the inner peripheral surface of the cover plate 10b with the concave groove 15.
[0043]
FIGS. 8A and 8B show a different form of the heat transfer element 1f in the second heat transfer element of the present invention and a method of manufacturing the same.
As shown in FIG. 8A, a base made of the same aluminum alloy as described above and having a rectangular-shaped cover groove 6 opened on the surface 3 and a rectangular-shaped concave groove 9a opened on the bottom surface of the cover groove 6. The member 2h is prepared in advance. In addition, a lid plate 10c having a rectangular cross section, which has the same rectangular shape as the lid groove 6 and is opened at the center of the bottom surface 12 and has a concave groove 15a having a rectangular cross section, is prepared. The concave groove 9a and the concave groove 15a have the same cross section and face each other. Note that an extruded member may be used for the base member 2h and the lid plate 10c.
[0044]
As shown by the arrow in FIG. 8A, after inserting the lower half of the pipe 17 having a square cross section into the concave groove 9a of the base member 2h, the cover plate 10c is fitted into the cover groove 6 of the base member 2h. At the same time, the upper half of the pipe 17 is inserted into the groove 15a (insertion / closing step). Then, friction stir welding using the welding tool 20 is performed along the abutting surfaces of the

side walls

5, 5 of the cover groove 6 of the base member 2h and the side surfaces 13, 14 of the cover plate 10c under the conditions described above ( Joining process).
As a result, as shown in FIG. 8 (B), the joints W1 and W2 are formed along the abutting surface, and the pipe 17 is formed with the concave groove 9a of the base member 2h and the cover plate 10a on almost the entire circumferential surface. And a heat transfer element 1f excellent in heat transfer property in close contact with the inner wall surface with the concave groove 15 can be obtained.
[0045]
FIG. 8C shows a heat transfer element 1g which is an application form of the heat transfer element 1f.
As shown in FIG. 8 (C), the base member 2j is made of the same aluminum alloy as described above, and has a lid groove 6 having a rectangular cross section opened on the surface 3 and a pair of parallel holes opened on the bottom surface of the lid groove 6 and parallel to each other. The lid plate 10d has a pair of concave grooves 15a having a rectangular cross section the same as the lid groove 6 and opening to the bottom surface 12. The

grooves

9a and 15a also have the same cross section and face each other. Note that an extruded profile may be used for the base member 2j and the lid plate 10d.
Similarly to the above, after individually inserting the lower half of the pipe 17 into each groove 9a of the base member 2j, the cover plate 10d is fitted into the cover groove 6 of the base member 2j, and is inserted into the groove 15a. The upper half of the pipe 17 is individually inserted (insertion / closing step).
[0046]
Next, along the abutting surfaces of the

side walls

5 and 5 of the lid groove 6 of the base member 2j and the side surfaces 13 and 14 of the lid plate 10d, friction stir welding is performed using the welding tool 20 according to the above-described conditions. (Joining step). As a result, as shown in FIG. 8 (C), the joints W1 and W2 are formed along the abutting surface, and the pair of square pipes 17 are formed with the concave grooves 9a of the base member 2j on the entire circumferential surface. It is possible to obtain a heat transfer element 1g which is in close contact with the inner wall surface with the concave groove 15a of the cover plate 10b and has excellent heat transfer properties.
The grooves 9a and the grooves 15a may not have the same cross section but may have a common width only and different heights (depths).
[0047]
The present invention is not limited to the embodiments and examples described above.
For example, the pipe for the heat medium has a regular polygonal shape having a hexagonal or octagonal cross section, a lid plate having a flat plate shape, and a lower half of a concave groove of a base member into which the pipe is inserted. The cross section may be substantially the same as the cross section of the lower half of the pipe, such as a trapezoid.
Further, the pipe for the heat medium may be made of copper or a copper alloy having a high thermal conductivity, or a titanium alloy having a relatively light weight and a required strength.
Further, the material of the base member may be made of copper or copper alloy having high thermal conductivity.
In addition, at least one of the front surface 3 and the rear surface 4 of the base member 2 and the like, and the upper surface 11 of the lid plate 10 at a position where the movement of the joining tool 20 is not hindered, Fins or the like may be protruded. In particular, it is preferable to use an extruded aluminum alloy material in which the lid groove 6 and the

concave grooves

8 and 9 are formed by extrusion for the base member 2 and the like, because the above-mentioned ridges and fins can be integrally provided. is there.
[Brief description of the drawings]
FIG. 1A is a perspective view of one embodiment of a first heat transfer element of the present invention, and FIG. 1B is a cross-sectional view taken along line BB in FIG.
2 (A) to 2 (D) are schematic views showing a manufacturing process of the heat transfer element.
FIGS. 3A, 3B, and 3D are schematic views showing a manufacturing process of the heat transfer element following FIG. 2D, and FIG. 3C is along a line CC in FIG. Sectional drawing in the direction of the arrow.
FIGS. 4A to 4C are schematic views showing different first heat transfer elements or manufacturing steps thereof.
FIGS. 5A and 5B are schematic diagrams showing a heat transfer unit using a plurality of the heat transfer elements.
6 (A) and 6 (B) are schematic views showing an application form of the heat transfer element of FIG. 1 or a manufacturing process thereof, and FIGS. 6 (C) and (D) are application forms of the heat transfer element of FIG. 4 or manufacture thereof. The schematic diagram which shows a process.
FIGS. 7A and 7B are schematic views showing one embodiment or a manufacturing process of the second heat transfer element of the present invention, and FIG. 7C is a schematic view showing an application form of the heat transfer element.
FIGS. 8A and 8B are schematic views showing different forms of a second heat transfer element or manufacturing steps thereof, and FIG. 8C is a schematic view showing an applied form of the heat transfer element.
[Explanation of symbols]
1, 1a-1d: heat transfer element, 2, 2c-2j: base member,
3 ………………………………………………………………………………………………………………………………….
6 ...

lid groove

7, 8, 9, 9a ... concave groove of base member,
10 ............ lid plate, 13, 14 ... side,
15, 15a ... groove of the cover plate, 16, 17 ... pipe,
20 joining tool, 22 tool body,
24 ……………………………………………………………………………………………………………………………………….
W1, W2 ... joint, X ... width of groove,
Y: Depth of groove, H: Depth of butt surface

Claims

A base material having a concave groove opening on the bottom surface of the lid groove and the lid groove having a rectangular cross section opening on the surface,
A pipe or heater for a heat medium inserted into the concave groove of the base material,
A lid plate fitted into the lid groove of the base material,
A heat transfer element, wherein a joint portion formed by friction stir welding is formed along each abutting surface between both side walls of the lid groove of the base material and both side surfaces of the lid plate.

A base material having a concave groove opening on the bottom surface of the lid groove and the lid groove having a rectangular cross section opening on the surface,
A lid plate having a concave groove fitted into the lid groove of the base material and opening on the bottom surface,
A heat medium pipe or heater inserted across the concave groove of the base material and the concave groove of the lid plate,
A heat transfer element, wherein a joint portion formed by friction stir welding is formed along each abutting surface between both side walls of the lid groove of the base material and both side surfaces of the lid plate.

The cross-section opening on the surface of the base member extends over the concave groove provided on the bottom surface of the rectangular lid groove or over the concave groove of the base material and the concave groove provided on the bottom surface of the lid plate fitted into the lid groove. An insertion step of inserting a pipe or heater for a heat medium,
A closing step of fitting the lid plate having substantially the same cross section to the lid groove of the base member,
A joining step of performing friction stir welding along each abutting surface of both side walls of the lid groove of the base material and both side surfaces of the lid plate,
A method for manufacturing a heat transfer element, comprising:

4. The cross-sectional shape of at least the lower half of the concave groove of the base plate is the same as or substantially similar to the cross-sectional shape of the lower half of the pipe or heater. 3. The method for manufacturing a heat transfer element according to claim 1.

The depth of the groove of the base plate in a form in which there is no groove on the bottom surface of the lid plate is in the range of less than 1.2 times the outer diameter of the pipe or heater or the outer diameter thereof. The method for manufacturing a heat transfer element according to claim 3.

The width of the groove is 1.1 times the outer diameter or the outer diameter of the pipe or heater,
The method for manufacturing a heat transfer element according to claim 3, wherein:

The welding tool used for friction stir welding in the welding step includes a tool stirrer and a friction stir pin that hangs coaxially from the center of the bottom surface thereof,
The axial length of the friction stir pin is in the range of the depth of the abutting surface to 60% or more thereof.
The method for manufacturing a heat transfer element according to claim 3, wherein: