JP4328512B2

JP4328512B2 - Die for extruding fine multi-hole tube, mandrel used for the die, and multi-hole tube manufactured using the die

Info

Publication number: JP4328512B2
Application number: JP2002305365A
Authority: JP
Inventors: 公寿平本; 英世山崎; 史生清水
Original assignee: Showa Denko KK
Current assignee: Resonac Holdings Corp
Priority date: 2001-10-23
Filing date: 2002-10-21
Publication date: 2009-09-09
Anticipated expiration: 2022-10-21
Also published as: JP2003200212A

Description

【０００１】
【発明の属する技術分野】
この発明は、熱交換器の熱交換用アルミニウム製扁平管等に用いられるような、多数の微細中空部を有する多穴管の製造用の押出ダイス、このダイスに用いられるマンドレル、前記ダイスを用いて製造された多穴管、熱交換チューブの製造方法、熱交換器、及び熱交換器の製造方法に関する。
【０００２】
【従来の技術】
例えば、自動車用のアルミニウム製凝縮器等の熱交換器には、一般に、図８に示すように、多数の微細中空部２０２が仕切壁２０１を介して幅方向に列設されたハモニカチューブと称されるような扁平状の熱交換チューブ２００が用いられている。
【０００３】
このような多穴管を押出成形によって製造する場合、押出ダイスとしては、管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされる図１１に示すようなマンドレル３００とを備えたものが用いられる。
【０００４】
前記マンドレル３００は、本体３０１と、この本体３０１から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体３０２とを有しており、柱状体３０２の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリンク部３０３となされている。
【０００５】
このようなマンドレル３００が、前記柱状体の先端ベアリンク部をダイス雌型の開口部内に臨ませた状態でダイス雌型に組み合わされて、ダイスが構成される。押出に際しては、マンドレル３００の後方から、コンテナに装填されたアルミニウム等の成形材料をステム等で加圧することにより、成形材料を雌型と柱状体３０２との間の隙間、及びマンドレル３００の各柱状体３０２間の隙間に流し込んでこれらの隙間から連続的に押出して、押出管を得る。
【０００６】
【発明が解決しようとする課題】
ところで、熱交換器の小型、高性能化の要請に伴い、熱交換器に用いられる多穴押出管２００にも、仕切壁２０１の薄肉化や中空部２０２の幅の縮小化等が望まれるようになってきている。そして、これを実現するために、前記ダイスのマンドレル３００に対しても、隣接する柱状体３０２のベアリング部３０３間の隙間３０４を一層小さくしたり、柱状体３０２のベアリング部分の幅を小さくすることが要求されている。
【０００７】
しかし、マンドレル３００において、隣接する柱状体３０２のベアリング部間の隙間３０４を小さくすると、押出時に、成形材料がこの隙間に十分に流れ込まず、管の仕切壁に欠肉が発生するという問題があった。
【０００８】
この問題を回避するため、図１１に示すように、ベアリング部３０３の押出方向後方側において、柱状体３０２の幅方向の外面をベアリング部の位置よりも内方に凹入させることにより、隣接する柱状体３０２間に幅広状の空間からなるポケット部３０５を形成し、押出に際してはこのポケット部３０５に成形材料を充填することにより、十分な成形材料を隣接するベアリング部間の隙間３０４に供給できるようにして、欠肉を防止する対策が採られることもある。
【０００９】
しかし、特に微細中空部の数が多くなると、ポケット部３０５の形成部分において柱状体３０２の幅方向の肉が少なくなることから、管２００の中空部２０２の幅を小さくするために柱状体３０２の先端ベアリング部分の幅を小さくすると、ポケット形成部分３０５において柱状体３０２はそれ以上に幅方向の肉が少なくなり、強度が低下して破損しやすくなるものであった。このため、管２００の中空部２０２の幅を小さくすることには限界があった。
【００１０】
この発明の目的は、仕切壁の欠肉を抑制することができるとともに、中空部の幅を小さくすることができる微細多穴管押出用ダイスを提供することにある。
【００１１】
この発明の他の目的は、前記の微細多穴管押出用ダイスに用いられるマンドレルを提供することにある。
【００１２】
この発明のさらに他の目的は、前記の微細多穴管押出用ダイスを用いて製造された多穴管を提供することにある。
【００１３】
この発明のさらに他の目的は、前記ダイスを用いた熱交換チューブの製造方法の提供にある。
【００１４】
この発明のさらに他の目的は、前記熱交換チューブを用いた熱交換器及び熱交換器の製造方法の提供にある。
【００１５】
【課題を解決するための手段】
この発明は、押出用ダイスのマンドレルの柱状体の厚み方向にポケット部を形成するとともに、そのポケット部の形状を工夫したものである。
【００１６】
即ち、この発明は以下のものにある。
（１）管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備え、
前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、
前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、
かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されていることを特徴とする微細多穴管押出用ダイス。
（２）柱状体の先端面に補強リブが突出形成されている前項１に記載の微細多穴管押出用ダイス。
（３）ベアリング部における柱状体の幅が２．０ｍｍ以下であり、隣り合う柱状体のベアリング部間の間隔が０．６ｍｍ以下である前項１または２に記載の微細多穴管押出用ダイス。
（４）ベアリング部における柱状体の厚み方向の少なくとも片面に、溝部が形成されている前項１ないし３のいずれかに記載の微細多穴管押出用ダイス。
（５）管の外周部を形成するダイス雌型と組み合わされるマンドレルであって、
本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、
前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、
かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されていることを特徴とする微細多穴管押出用ダイスに用いられるマンドレル。
（６）柱状体の先端面に補強リブが突出形成されている前項５に記載のマンドレル。
（７）ベアリング部における柱状体の幅が２．０ｍｍ以下であり、隣り合う柱状体のベアリング部間の間隔が０．６ｍｍ以下である前項５または６に記載のマンドレル。
（８）ベアリング部における柱状体の厚み方向の少なくとも片面に、溝部が形成されている前項５ないし７のいずれかに記載の微細多穴管押出用ダイス。
（９）管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備えた押出用ダイスであって、
前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、
前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、
かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されている押出用ダイス、
を用いて製造され、幅方向に仕切壁によって仕切られた多数の微細中空部を有する多穴管。
（１０）押出用ダイスの柱状体の先端面に補強リブが突出形成されている前項９に記載の微細多穴管。
（１１）中空部の幅が２．０ｍｍ以下であり、仕切壁の肉厚が０．６ｍｍ以下である前項９または１０に記載の微細多穴管。
（１２）押出用ダイスのベアリング部における柱状体の厚み方向の少なくとも片面に、溝部が形成されていることにより、中空部における隣接する仕切壁間に突出部が形成されている前項９ないし１１のいずれかに記載の微細多穴管。
（１３）管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備え、前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されている押出用ダイスを用い、
この押出用ダイスから成形材料を押し出すことを特徴とする熱交換チューブの製造方法。
（１４）押出用ダイスの柱状体の先端面に補強リブが突出形成されている前項１３に記載の熱交換チューブの製造方法。
（１５）押出用ダイスのベアリング部における柱状体の幅が２．０ｍｍ以下であり、隣り合う柱状体のベアリング部間の間隔が０．６ｍｍ以下である前項１３または１４に記載の熱交換チューブの製造方法。
（１６）押出用ダイスのベアリング部における柱状体の厚み方向の少なくとも片面に、溝部が形成されている前項１３ないし１５のいずれかに記載の熱交換チューブの製造方法。
（１７）管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備えた押出用ダイスであって、
前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、
前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、
かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されている押出用ダイス、
を用いて製造され、幅方向に仕切壁によって仕切られた多数の微細中空部を有する熱交換チューブを備えた熱交換器。
（１８）押出用ダイスの柱状体の先端面に補強リブが突出形成されている前項１７に記載の熱交換器。
（１９）熱交換チューブの中空部の幅が２．０ｍｍ以下であり、仕切壁の肉厚が０．６ｍｍ以下である前項１７または１８に記載の熱交換器。
（２０）熱交換チューブの中空部における隣接する仕切壁間にフィン部が突出形成されている前項１７ないし１９のいずれかに記載の熱交換器。
（２１）管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備えた押出用ダイスであって、
前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、
前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、
かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されている押出用ダイス、
を用いて製造され、幅方向に仕切壁によって仕切られた多数の微細中空部を有する熱交換チューブを用い、
この熱交換チューブとアウターフィンとを交互に配置してろう付する熱交換器の製造方法。
（２２）押出用ダイスの柱状体の先端面に補強リブが突出形成されている前項２１に記載の熱交換器の製造方法。
（２３）熱交換チューブの中空部の幅が２．０ｍｍ以下であり、仕切壁の肉厚が０．６ｍｍ以下である前項２１または２２に記載の熱交換器の製造方法。
（２４）熱交換チューブの中空部における隣接する仕切壁間にフィン部が突出形成されている前項２１ないし２３のいずれかに記載の熱交換器の製造方法。
【００１７】
即ち、この発明の第１のものは、管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備え、前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されていることを特徴とする微細多穴管押出用ダイスにある。
【００１８】
この微細多穴管押出用ダイスでは、マンドレルの柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されるとともに、柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成されているから、押出時には、このポケット部に成形材料がスムーズに流れ込んで充填される。このため、十分な量の成形材料が隣接する柱状体のベアリング部間の隙間に供給される。その結果、ベアリング部間の隙間を小さくしても、管の仕切壁の欠肉が抑制される。しかも、柱状体の幅方向の肉を少なくすることによる柱状体の幅方向のポケット部を必ずしも設けなくても良いから、その分ベアリンク部における柱状体の幅を小さくでき、管の中空部の幅を小さくできる。
【００１９】
また、ポケット部からベアリング部に続く面が内方凸の湾曲面に形成されているから、この部分に角部がなくなり、柱状体に加わる押出圧力による角部への応力集中を避けることができ、柱状体の破損が抑制される。
【００２０】
なお、マンドレルの柱状体の厚み方向の少なくとも片面側にポケット部を設けたことにより、柱状体の厚み方向の肉が減少して、その分の強度低下を来す。このため、柱状体の先端面に補強リブが突出形成された構成として、マンドレルの強度向上を図るものとしても良い。
【００２１】
また、ベアリング部における柱状体の幅が２．０ｍｍ以下であり、隣り合う柱状体のベアリング部間の間隔が０．６ｍｍ以下であるのが、この発明の効果を特に発揮できる点で好ましい。
【００２２】
また、ベアリング部における柱状体の厚み方向の少なくとも片面に、溝部が形成されている構成としても良い。この場合には、溝部に対応する突出部が、多穴管に形成されるから、例えば多穴管を熱交換器の熱交換チューブとして用いる場合には、この突出部を、中空部を流れる冷媒との接触面積を増大させるためのインナーフィンとして用いることができる。
【００２３】
この発明の第２のものは、管の外周部を形成するダイス雌型と組み合わされるマンドレルであって、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されていることを特徴とする微細多穴管押出用ダイスに用いられるマンドレルにある。
【００２４】
このマンドレルをダイス雌型と組み合わせることにより、仕切壁に欠肉のない中空部の幅の小さい多穴管を得ることができる。
【００２５】
このマンドレルにおいても、強度向上の観点から、柱状体の先端面に補強リブが突出形成されている構成としても良い。また、ベアリング部における柱状体の幅が２．０ｍｍ以下であり、隣り合う柱状体のベアリング部間の間隔が０．６ｍｍ以下であっても良い。また、ベアリング部における柱状体の厚み方向の少なくとも片面に、溝部が形成されている構成としても良い。
【００２６】
この発明の第３のものは、管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備え、前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されている押出用ダイスを用いて製造され、幅方向に仕切壁によって仕切られた多数の微細中空部を有する多穴管にある。
【００２７】
この多穴管では、仕切壁に欠肉のない中空部の幅の小さいものとすることができる。
【００２８】
この多穴管において、押出用ダイスの柱状体の先端面に補強リブが突出形成されていても良いし、多穴管の中空部の幅が２．０ｍｍ以下であり、仕切壁の肉厚が０．６ｍｍ以下であっても良い。また、押出用ダイスのベアリング部における柱状体の厚み方向の少なくとも片面に、溝部が形成されていることにより、中空部における隣接する仕切壁間に突出部が形成されていても良い。
【００２９】
この発明の第４のものは、管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備え、前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されている押出用ダイスを用い、この押出用ダイスから成形材料を押し出すことを特徴とする熱交換チューブの製造方法にある。
【００３０】
この製造方法によれば、仕切壁に欠肉のない中空部の幅の小さい熱交換チューブを製造することができる。
【００３１】
この製造方法においても、押出用ダイスの柱状体の先端面に補強リブが突出形成されていても良いし、押出用ダイスのベアリング部における柱状体の幅が２．０ｍｍ以下であり、隣り合う柱状体のベアリング部間の間隔が０．６ｍｍ以下であっても良いし、押出用ダイスのベアリング部における柱状体の厚み方向の少なくとも片面に、溝部が形成されていても良い。
【００３２】
この発明の第５のものは、管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備えた押出用ダイスであって、
前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、
前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、
かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されている押出用ダイス、
を用いて製造され、幅方向に仕切壁によって仕切られた多数の微細中空部を有する熱交換チューブを備えた熱交換器にある。
【００３３】
この熱交換器では、仕切壁に欠肉のない中空部の幅の小さい熱交換チューブを備えているので、熱交換チューブの熱交換効率ひいては熱交換器全体の熱交換効率を向上できる。
【００３４】
この熱交換器においても、押出用ダイスの柱状体の先端面に補強リブが突出形成されていても良いし、熱交換チューブの中空部の幅が２．０ｍｍ以下であり、仕切壁の肉厚が０．６ｍｍ以下であっても良いし、熱交換チューブの中空部における隣接する仕切壁間にフィン部が突出形成されていても良い。
【００３５】
また、この発明の第６のものは、管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備えた押出用ダイスであって、
前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、
前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、
かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されている押出用ダイス、
を用いて製造され、幅方向に仕切壁によって仕切られた多数の微細中空部を有する熱交換チューブを用い、
この熱交換チューブとアウターフィンとを交互に配置してろう付する熱交換器の製造方法にある。
【００３６】
この製造方法では、仕切壁に欠肉のない中空部の幅の小さい熱交換チューブを用いるので、熱交換チューブの熱交換効率ひいては全体の熱交換効率に優れた熱交換器の製造が可能になる。
【００３７】
この熱交換器の製造方法においても、押出用ダイスの柱状体の先端面に補強リブが突出形成されていても良いし、熱交換チューブの中空部の幅が２．０ｍｍ以下であり、仕切壁の肉厚が０．６ｍｍ以下であっても良いし、熱交換チューブの中空部における隣接する仕切壁間にフィン部が突出形成されていても良い。
【００３８】
【発明の実施の形態】
以下に説明する実施形態において、押出加工の対象となる多穴管は、図７（ａ）（ｂ）に示されるように、仕切壁１０１を介して多数の微細中空部１０２が幅方向に列設されたアルミニウム（その合金を含む）製扁平管１００であり、熱交換器の冷媒流通用の熱交換チューブに用いられるものである。かつ、このアルミニウム管の厚み方向（図７の上下方向）の両対向壁部には、幅方向（図７の左右方向）両側の中空部を除く各中空部の幅方向中央部の位置において、それぞれ対向壁部に向かって途中の位置まで突出するフィン部１０３が、アルミニウム管１００の長さ方向に沿って一体に形成されている。従って、幅方向両側の中空部を除く前記各中空部の断面形状はＨ形となっている。
【００３９】
図１は、この発明の一実施形態に係る押出ダイス１のマンドレル２を示す斜視図、図２は同じく雌型ダイス３の押出方向後方（入側）から見た正面図、図３は前記雌型ダイス３とマンドレル２とを組み合わせた状態での図１のIII−III線断面図、図４は図３のIV−IV線断面図である。
【００４０】
図１〜図４において、前記ダイス雌型３は、その押出方向後面の中央部に、アルミニウム管の外周形状に対応する扁平な開口部３１を有するとともに、この開口部３１に連通する態様で、ダイス雌型３の軸方向を貫通する押出材通過孔３２が形成されている。また、前記開口部３１の縁部に、アルミニウム管の外周面を規定するベアリンク部３３が形成されている。
【００４１】
一方、前記マンドレル２は、扁平状のマンドレル本体２１と、マンドレル本体２１の先端部から櫛歯状に一体突出し、幅方向（図４の左右方向）に間隔を置いて列設された複数個の柱状体２２とを有している。
【００４２】
前記マンドレル本体２１における前記柱状体２２との連設部２３は、厚み方向（図４の上下方向）の両外面が先端に向かって先細となる傾斜面となされており、押出時にマンドレル本体２１の厚み方向の両側の成形材料が、柱状体２２に向かって流れ込みやすくなっている。
【００４３】
前記柱状体２２は、前記アルミニウム管１００の中空部１０２をそれぞれ形成するためのものであり、その先端部の形状は、前記各中空部１０２の断面形状に対応している。即ち、列設方向両側の柱状部２２ａを除く各柱状部２２には、厚み方向の両面中央部に、前記アルミニウム管１００のフィン部１０３を形成するための溝部２４が厚み方向の途中の位置まで延びて形成されており、従って各柱状部２２は、アルミニウム管１００の中空部１０２の断面形状に対応して断面Ｈ形に形成されている。また、前記溝部２４は柱状体２２の基端部近くまで延びている。また、柱状体２２の先端外周部が、前記アルミニウム管１００の中空部内周面を規定するベアリング部２５となされている。
【００４４】
ベアリンク部２５の押出方向後方側において、柱状体２２の厚み方向の両側面は、ベアリング部２５の位置よりも内方に削り込まれて凹入しており、この部分に、成形材料充填用空間としてのポケット部２７が形成されている。
【００４５】
さらに、図３に詳細に示すように、前記柱状体２２の基端部から前記ポケット部２７に続く面２８は傾斜面となされ、これにより成形材料のポケット部２７への導入を促進しうるものとなされている。なお、傾斜面ではなく、成形材料のポケット部２７への導入を促進しうる曲面に形成されていても良い。
【００４６】
一方、ポケット部２７からベアリング部２５に続く面２９は、内方凸の湾曲面に形成されている。このように湾曲面に形成したのは、ポケット部２７からベアリング部２５に続く面２９に角部が生じるのをなくすためであり、押出時に角部に応力が集中して柱状体２２が破損するのを防止するためである。
【００４７】
また、前記柱状体２２の幅は、この実施形態では、基端部からベアリング部２５に到るまで同じであり、かつ幅方向の両側面２６がベアリング部に到るまで段差のない平坦面に形成されている。なお、柱状体２２のベアリング部２５を幅方向に突出させた構成としても良い。この場合には、柱状体２２の幅方向の両側面からベアリング部にかけての段差部分を、厚み方向と同じく湾曲面に形成しても良い。また、特に柱状体２２の幅に余裕がある場合には、隣接柱状体の間にもポケット部を設けても良い。
【００４８】
上記構成のマンドレル２が、その柱状体２２の先端のベアリング部２５とダイス雌型３のベアリング部３３とが対向するように、柱状体２２の先端部をダイス雌型３の開口部３１に臨ませて配置され、ダイス１が構成される。なお、マンドレル２は、必要に応じて図示しない支持体に焼き嵌め等により固定支持された状態でダイス雌型と組み合わされても良い。また、マンドレル２を例えばマンドレル本体２１と柱状体２２に分割構成し、これらを焼き嵌め等により固定しても良い。
【００４９】
この状態で、ダイス１がセットされた図示しないコンテナに、成形材料としてのアルミニウムビレットを装填し、常法に従って押出を実施する。押圧によってアルミニウム成形材料はマンドレル２の厚み方向両側において、図３に矢印で示すように、マンドレル本体２１と柱状体２２の連設部２３の傾斜面に沿って柱状体２２方向へと流動し、柱状体２２の厚み方向の両側に形成されたポケット部２７に充填される。
【００５０】
さらに押圧が加わることにより、ポケット部に充填された成形材料は、柱状体２２のベアリング部２５とダイス雌型のベアリング部３３との間の隙間１１から押し出されると同時に、隣接柱状体２２同士の間に十分に供給されて、隣接柱状体２２のベアリング部２５間の隙間１２から押し出される。そして、成形材料が、これらの隙間１１，１２から連続的に押し出されることにより、図７に示したような断面形状のアルミニウム押出管１００が製造される。
【００５１】
この押出しに際して、各柱状体２２のベアリング部２５は、ポケット部２７に充填された成形材料を介して背後から押出方向の前方への応力を受けるが、ポケット部２７からベアリング部２５へと続く面２９は湾曲面に形成されていて角部が存在しないから、前記応力が分散され、柱状体の破損が抑制される。
【００５２】
この実施形態に係る押出ダイスでは、柱状体２２の厚み方向の両側にポケット部２７が形成されており、各柱状体２２の間にはポケット部が設けられていない。このため、ポケット部を形成するために各柱状体２２の幅を細くした場合に比べて、各柱状体のベアリング部における幅を小さくすることができ、従って、アルミニウム管の中空部１０２の幅を小さくすることができる。
【００５３】
しかも、柱状体２２の厚み方向においてポケット部２７を設けたから、柱状体の幅方向にポケット部を設けた場合と同様に、隣接柱状体間の幅方向の隙間１２へと十分に成形材料が供給され、隙間１２を小さくしてもアルミニウム管１００の仕切壁１０１に欠肉が生じるのを抑制できる。
【００５４】
具体的には、図１（ｂ）に示すように、ベアリング部２５における柱状体２２の幅Ｗが２．０ｍｍ以下に設定され、隣り合う柱状体２２、２２のベアリング部間の間隔Ｇが０．６ｍｍ以下に設定される場合に、効果が大きい。つまり、仕切壁１０１の厚みＴ１が０．６ｍｍ以下で、中空部１０２の幅Ｗ１が２．０ｍｍ以下の押出アルミニウム管１００を製造する場合に有効な効果が発揮される。
【００５５】
図５は、この発明の変形例を示すものである。この変形例では、各柱状体２２の正面視Ｈ形の先端面に、「Ｈ」形状の長辺部分に沿って２個の補強リブ５０を突設したものである。これにより、押出時に柱状体２２のベアリング部３３に加わる背圧（図５（ｃ）に矢印で示す）に対して、柱状体２２を強化することができる。
【００５６】
また、以上の実施形態では、マンドレル２の柱状体を断面Ｈ形に形成して、断面Ｈ形の中空部１０２を有するアルミニウム管１００を押し出す場合を示したが、図６に示すように、断面矩形の柱状体２２に形成して、図８に示すような多数の矩形中空部２０２が仕切壁２０１によって幅方向に仕切られたアルミニウム管２００を押し出す構成としても良い。図６において、５０は、柱状体２２の先端面に必要に応じて設けられた突設補強リブである。
【００５７】
図９は、前述したアルミニウム管１００または２００を、熱交換チューブ２５０として用いた熱交換器としてのパラレルフロー形凝縮器を示す正面図である。
【００５８】
この凝縮器は、アルミニウム管１００または２００からなる熱交換チューブ２５０と、アルミニウム製の波形アウターフィン２５１とが上下に交互に配置されるとともに、熱交換チューブ２５０の両端が一対のアルミニウム製ヘッダー２５２、２５２に接続されてなるものである。そして、熱交換チューブ２５０とヘッダー２５２とがろう付けされるとともに、熱交換チューブ２５０とアウターフィン２５１もまたろう付されている。
【００５９】
なお、図９に示す２５３は冷媒入口、２５４は同出口、２５５は最外側のアウターフィンの外側に配置された一対のサイドプレート、２５６は熱交換チューブで構成される冷媒通路を蛇行通路とするために、各ヘッダー２５２の内部を仕切る仕切りであり、これらの各熱交換器構成要素もろう付によって対応部位に接合されている。
【００６０】
この熱交換器では、熱交換チューブ２５０として、中空部の幅が小さく仕切壁の厚さも薄いアルミニウム管１００または２００が用いられているから、熱交換効率に優れている。特に、熱交換チューブ２５０としてアルミニウム管１００を用いた場合には、隣接する仕切壁間において突出するフィン部がインナーフィンとして機能するため、熱交換効率がさらに優れたものとなる。
【００６１】
【実施例】
この実施形態に係るダイスを用いたときの効果を示すため、以下のような試験を行った
（実施例１）
図８に示すような断面矩形の中空部１０２が幅方向に列設されたアルミニウム管２００を押し出すダイス１として、図６に示すような断面矩形の柱状体２２を有するマンドレル２を備え、マンドレル２の幅方向において隣接する柱状体２２間にポケット部を形成した従来品に係るダイスと、幅方向にポケット部を形成することなく、厚み方向の両面側にポケット部２７を形成した本発明実施品に係るダイスを供試品とした。ただし、柱状体２２の先端の補強リブ５０は設けなかった。
【００６２】
そして、柱状体２２のベアリンク部２５の高さＨを１．５ｍｍで一定とした状態で、柱状体２２の幅Ｗ２（図６に示す）と隣接柱状体２２間の隙間１２の大きさＧ２を表１のように各種に設定して、アルミニウムビレットを押し出し、押出成形性の限界を調べた。その結果を表１、及び図１０に示す。図１０において、縦軸が隣接柱状体２２間の隙間１２の大きさＧ２であり、横軸が柱状体２２の幅Ｗ２を示す。また、黒四角点を結ぶ線は、従来品の押出成形限界を示し、黒丸点を結ぶ線は、実施品の押出成形限界を示し、各線で囲まれた右上領域が良好な押出を行いうる範囲を、左下領域が押出不良または押出困難な範囲をそれぞれ示す。
【００６３】
【表１】

【００６４】
表１及び図１０からわかるように、マンドレル２２の幅方向にポケット部を形成した従来品では、柱状体の幅Ｗ２が２．０ｍｍのときは隙間Ｇ２を０．１ｍｍに設定すると仕切壁２０１に欠肉が生じたり、柱状体そのものが破損した。また、柱状体２２の幅Ｗ２が１．０ｍｍ、０．８ｍｍ、０．５ｍｍ、０．２５ｍｍのものでは、隙間Ｇ２がそれぞれ０．１３ｍｍ、０．１５ｍｍ、０．２２ｍｍ、０．６ｍｍになると、仕切壁２０１に欠肉が生じたり、柱状体そのものが破損した。これに対し、マンドレルの厚み方向にポケット部を形成した本発明実施品では、柱状体２２の幅Ｗ２が０．２ｍｍ以上、隙間Ｇ２が０．０８ｍｍ以上であれば、仕切壁２０１の欠肉や柱状体２２の破損が生じなかった。また、柱状体２２の幅Ｗ２が０．１５ｍｍのとき、０．１ｍｍ、０．０５ｍｍのときは、隙間Ｇ２がそれぞれ０．１０ｍｍ、０．１８ｍｍ、０．６であっても、仕切壁２０１の欠肉や柱状体２２の破損が生じなかった。
【００６５】
従って、本発明実施品によれば、押出成形限界を引き上げることができるものであることを確認し得た。
【００６６】
なお、図１０の網掛け部分においては、本実施品であっても、押出しが困難であった。
（実施例２）
実施例１と同じ形式のマンドレルを用い、マンドレル２の幅方向において隣接する柱状体２２間にポケット部を形成した従来品に係るダイスと、幅方向にポケット部を形成することなく、厚み方向の両面側にポケット部を形成した本発明実施品に係るダイスを供試品とした。なお、柱状体先端の補強リブ５０は設けなかった。
【００６７】
そして、柱状体２２のベアリンク部２５の高さＨを０．７ｍｍ、隣接柱状体２２間の隙間１２の大きさＧ２を０．２ｍｍ一定とした状態で、柱状体２２の幅Ｗ２を０．５ｍｍ、０．８ｍｍ、１．０ｍｍにそれぞれ設定して、アルミニウムビレットを押し出し、ダイスの寿命を調査した。
【００６８】
その結果、柱状体２２の幅Ｗ２が０．５ｍｍの場合、従来品では０．９トンのビレットを押し出したところでダイス寿命に達したのに対し、本実施品では２．１トンであり、本実施品の寿命は従来品の約２．３倍であった。また、柱状体２２の幅Ｗ２が０．８ｍｍの場合、従来品では寿命までの押出量が１．５トンであったのに対し、本実施品では２．５トンであり、従来品の約１．６倍の寿命であった。また、柱状体２２の幅Ｗ２が１．０ｍｍの場合、従来品では寿命までの押出量が２．２トンであったのに対し、本実施品では２．６トンであり、従来品の約１．１８倍の寿命であった。
【００６９】
このように、本発明実施品によれば、従来品よりも寿命を延ばすことができ、特に柱状体２２の幅Ｗ２を小さく設定した場合の寿命を顕著に延ばすことができることを確認し得た。
【００７０】
【発明の効果】
上述したように、管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備え、前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されていることを特徴とする微細多穴管押出用ダイスによれば、押出時に、このポケット部に成形材料がスムーズに流れ込んで充填されるため、十分な量の成形材料が隣接する柱状体のベアリング部間の隙間に供給される。
【００７１】
その結果、ベアリング部間の隙間を小さくしても、管の仕切壁の欠肉が抑制される。しかも、柱状体の幅方向の肉を少なくすることによる柱状体の幅方向のポケット部を必ずしも設けなくても良いから、その分ベアリンク部における柱状体の幅を小さくでき、管の中空部の幅を小さくできる。
【００７２】
また、ポケット部からベアリング部に続く面が内方凸の湾曲面に形成されているから、この部分に角部がなくなり、柱状体に加わる押出圧力による角部への応力集中を避けることができ、柱状体の破損が抑制される。
【００７３】
前記押出用ダイスにおいて、柱状体の先端面に補強リブが突出形成されている場合には、マンドレルの強度向上を図ることができる。
【００７４】
また、前記押出用ダイスによれば、ベアリング部における柱状体の幅が２．０ｍｍ以下であり、隣り合う柱状体のベアリング部間の間隔が０．６ｍｍ以下である微細多穴管の押出も可能になる。
【００７５】
また、ベアリング部における柱状体の厚み方向の少なくとも片面に、溝部が形成されている場合には、溝部に対応する突出部が、多穴管に形成されるから、例えば多穴管を熱交換器の熱交換チューブとして用いる場合には、この突出部を、中空部を流れる冷媒との接触面積を増大させるためのインナーフィンとして用いることができる。
【００７６】
また、管の外周部を形成するダイス雌型と組み合わされるマンドレルであって、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されていることを特徴とする微細多穴管押出用ダイスに用いられるマンドレルによれば、ダイス雌型との組み合わせにより、仕切壁に欠肉のない中空部の幅の小さい多穴管を得ることができる。
【００７７】
このマンドレルにおいて、柱状体の先端面に補強リブが突出形成されている場合には、強度を向上できる。
【００７８】
また、ベアリング部における柱状体の幅が２．０ｍｍ以下であり、隣り合う柱状体のベアリング部間の間隔が０．６ｍｍ以下である場合には、多穴管の中空部を極めて微細なものとすることができる。
【００７９】
また、ベアリング部における柱状体の厚み方向の少なくとも片面に、溝部が形成されている場合には、この突出部を例えば熱交換チューブのインナーフィンとして用いることができる。
【００８０】
また、管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備え、前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されている押出用ダイスを用いて製造され、幅方向に仕切壁によって仕切られた多数の微細中空部を有する多穴管によれば、仕切壁に欠肉のない中空部の幅の小さい多穴管となし得る。
【００８１】
この多穴管において、押出用ダイスの柱状体の先端面に補強リブが突出形成されている場合には、マンドレルの強度向上により、仕切壁の欠肉をさらになくして、中空部の幅のさらに小さい多穴管となし得る。
【００８２】
また、前記多穴管の中空部の幅が２．０ｍｍ以下であり、仕切壁の肉厚が０．６ｍｍ以下である場合には、中空部の幅が小さく仕切り壁の肉厚も薄い多穴管となし得る。
【００８３】
また、押出用ダイスのベアリング部における柱状体の厚み方向の少なくとも片面に、溝部が形成されていることにより、中空部における隣接する仕切壁間に突出部が形成されている場合には、この突出部を例えば熱交換チューブのインナーフィンとして用いることができる。
【００８４】
また、管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備え、前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されている押出用ダイスを用い、この押出用ダイスから成形材料を押し出すことを特徴とする熱交換チューブの製造方法によれば、仕切壁に欠肉のない中空部の幅の小さい熱交換チューブを製造することができる。
【００８５】
この製造方法において、押出用ダイスの柱状体の先端面に補強リブが突出形成されている場合には、マンドレルの強度向上により、仕切壁の欠肉をさらになくして、中空部の幅のさらに小さい熱交換チューブを製造できる。
【００８６】
また、押出用ダイスのベアリング部における柱状体の幅が２．０ｍｍ以下であり、隣り合う柱状体のベアリング部間の間隔が０．６ｍｍ以下である場合には、中空部の幅が２．０ｍｍ以下と小さく、仕切壁の肉厚も０．６ｍｍ以下と薄い熱交換チューブを製造できる。
【００８７】
また、押出用ダイスのベアリング部における柱状体の厚み方向の少なくとも片面に、溝部が形成されている場合には、中空部における隣接する仕切壁間にフィン部が突出形成されている熱交換チューブを製造できる。
【００８８】
また、管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備えた押出用ダイスであって、前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されている押出用ダイス、を用いて製造され、幅方向に仕切壁によって仕切られた多数の微細中空部を有する熱交換チューブを備えた熱交換器によれば、仕切壁に欠肉のない中空部の幅の小さい熱交換チューブにより、熱交換チューブの熱交換効率ひいては熱交換器全体の熱交換効率を向上できる。
【００８９】
この熱交換器において、押出用ダイスの柱状体の先端面に補強リブが突出形成されている場合には、熱交換チューブの仕切壁の欠肉をさらになくし中空部の幅をさらに小さくできるから、さらに熱交換効率の良い熱交換器となし得る。
【００９０】
この熱交換器において、熱交換チューブの中空部の幅が２．０ｍｍ以下であり、仕切壁の肉厚が０．６ｍｍ以下である場合には、熱交換チューブの中空部の幅が小さく仕切り壁の肉厚も薄いから、熱交換器の熱交換効率を良いものとなし得る。
【００９１】
また、熱交換チューブの中空部における隣接する仕切壁間にフィン部が突出形成されている場合には、熱交換チューブを流れる冷媒とフィン部との接触により、さらに熱交換効率が増大する。
【００９２】
また、管の外周部を形成するダイス雌型と、このダイス雌型と組み合わされるマンドレルとを備えた押出用ダイスであって、前記マンドレルは、本体と、この本体から櫛歯状に突出し幅方向に間隔を置いて列設された複数個の柱状体とを有し、柱状体の先端外周部が、管の幅方向に列設された複数個の中空部の内周面を形成するベアリング部となされ、前記ベアリング部よりも押出方向後方側において、前記柱状体の厚み方向の少なくとも片側外面が、前記ベアリング部の位置よりも厚み方向内方に凹入することにより、柱状体の厚み方向の少なくとも片面側に、成形材料充填用空間であるポケット部が形成されており、かつ前記柱状体の基端部から前記ポケット部に続く面は、成形材料のポケット部への導入促進用の傾斜面ないし曲面に形成される一方、ポケット部から前記ベアリング部に続く面が内方凸の湾曲面に形成されている押出用ダイス、を用いて製造され、幅方向に仕切壁によって仕切られた多数の微細中空部を有する熱交換チューブを用い、この熱交換チューブとアウターフィンとを交互に配置してろう付する熱交換器の製造方法によれば、仕切壁に欠肉のない中空部の幅の小さい熱交換チューブを用いるので、熱交換チューブの熱交換効率ひいては全体の熱交換効率に優れた熱交換器の製造が可能になる。
【００９３】
この熱交換器の製造方法において、押出用ダイスの柱状体の先端面に補強リブが突出形成されている場合には、熱交換チューブの仕切壁の欠肉をさらになくし中空部の幅をさらに小さくできるから、さらに熱交換効率の良い熱交換器を製造できる。
【００９４】
また、熱交換チューブの中空部の幅が２．０ｍｍ以下であり、仕切壁の肉厚が０．６ｍｍ以下である場合には、熱交換チューブの中空部の幅が小さく仕切り壁の肉厚も薄いから、熱交換器の熱交換効率を良いものとなし得る。
【００９５】
また、熱交換チューブの中空部における隣接する仕切壁間にフィン部が突出形成されている場合には、熱交換チューブを流れる冷媒とフィン部との接触により、さらに熱交換効率の良い熱交換器を製造できる。
【図面の簡単な説明】
【図１】（ａ）は、この発明の一実施形態に係る押出ダイスのマンドレルを示す斜視図、（ｂ）は柱状体の平面図である。
【図２】同じく押出ダイスの雌型ダイスを押出方向後方（入側）から見た正面図である。
【図３】雌型ダイスとマンドレルとを組み合わせた押出ダイスの要部断面図である。
【図４】図３のIV−IV線断面図である。
【図５】この発明の変形例を示すもので、（ａ）はマンドレルの要部の斜視図、（ｂ）は押出出側から見た柱状体の正面図、（ｃ）は柱状体の側面図である。
【図６】この発明の他の実施形態を示すもので、押出出側から見たマンドレルの要部正面図である。
【図７】（ａ）は図１〜図４のダイスによって製造される押出アルミニウム管の断面斜視図、（ｂ）は同じく正面断面拡大図である。
【図８】（ａ）は図６のマンドレルを備えたダイスによって製造される押出アルミニウム管の断面斜視図、（ｂ）は同じく正面断面拡大図である。
【図９】この発明の一実施形態に係る熱交換器の正面図である。
【図１０】実施例で行った押出性の限界試験の結果を示すグラフである。
【図１１】従来の押出ダイスに用いられるマンドレルの斜視図である。
【符号の説明】
１・・・・・・ダイス
２・・・・・・マンドレル
２１・・・・・マンドレル本体
２２・・・・・柱状体
２３・・・・・連設部
２５・・・・・ベアリング部
２７・・・・・ポケット部
２８・・・・・柱状体の基端部からポケット部へと続く面
２９・・・・・ポケット部からアプローチ部へと続く面
３０・・・・・ダイス雌型
５０・・・・・補強リブ
１００・・・・管
１０１・・・・仕切壁
１０２・・・・中空部
２００・・・・管
２０１・・・・仕切壁
２０２・・・・中空部
２５０・・・・熱交換チューブ
２５１・・・・アウターフィン[0001]
BACKGROUND OF THE INVENTION
The present invention uses an extrusion die for manufacturing a multi-hole tube having a large number of fine hollow portions, such as an aluminum flat tube for heat exchange of a heat exchanger, a mandrel used for the die, and the die It is related with the manufacturing method of the multi-hole pipe manufactured in this way, the heat exchange tube, the heat exchanger, and the heat exchanger.
[0002]
[Prior art]
For example, a heat exchanger such as an aluminum condenser for automobiles is generally called a harmonica tube in which a large number of fine hollow portions 202 are arranged in the width direction via a partition wall 201 as shown in FIG. A flat heat exchange tube 200 as described above is used.
[0003]
When such a multi-hole tube is manufactured by extrusion molding, the extrusion die includes a die female die that forms the outer peripheral portion of the tube, and a mandrel 300 as shown in FIG. 11 combined with the die female die. Things are used.
[0004]
The mandrel 300 has a main body 301 and a plurality of columnar bodies 302 that protrude from the main body 301 in a comb-like shape and are arranged at intervals in the width direction. The bare link portion 303 forms the inner peripheral surface of a plurality of hollow portions arranged in the width direction of the tube.
[0005]
Such a mandrel 300 is combined with a female die in a state where the end bare link portion of the columnar body faces the opening of the female die, thereby forming a die. At the time of extrusion, a molding material such as aluminum loaded in a container is pressed with a stem or the like from the rear of the mandrel 300, so that the molding material is pressed between the female mold and the columnar body 302, and each columnar shape of the mandrel 300. Pour into the gaps between the bodies 302 and continuously extrude through these gaps to obtain extruded tubes.
[0006]
[Problems to be solved by the invention]
By the way, with the demand for miniaturization and high performance of the heat exchanger, it is desired that the multi-hole extruded tube 200 used for the heat exchanger also has a thinner partition wall 201 and a reduced width of the hollow portion 202. It is becoming. In order to achieve this, the gap 304 between the bearing portions 303 of the adjacent columnar bodies 302 is further reduced with respect to the mandrel 300 of the die, or the width of the bearing portions of the columnar bodies 302 is reduced. Is required.
[0007]
However, in the mandrel 300, if the gap 304 between the bearing portions of the adjacent columnar bodies 302 is made small, the molding material does not sufficiently flow into the gap during extrusion, and there is a problem that a thin wall is generated in the partition wall of the pipe. It was.
[0008]
In order to avoid this problem, as shown in FIG. 11, on the rear side in the extrusion direction of the bearing portion 303, the outer surface in the width direction of the columnar body 302 is recessed inward from the position of the bearing portion so as to be adjacent to each other. By forming a pocket portion 305 having a wide space between the columnar bodies 302 and filling the pocket portion 305 with a molding material during extrusion, a sufficient molding material can be supplied to the gap 304 between the adjacent bearing portions. In this way, measures to prevent missing meat may be taken.
[0009]
However, particularly when the number of fine hollow portions increases, the width in the width direction of the columnar body 302 decreases at the portion where the pocket portion 305 is formed. Therefore, in order to reduce the width of the hollow portion 202 of the tube 200, When the width of the tip bearing portion is reduced, the columnar body 302 has a smaller thickness in the width direction at the pocket forming portion 305, and the strength is reduced and the columnar body 302 is easily damaged. For this reason, there is a limit to reducing the width of the hollow portion 202 of the tube 200.
[0010]
An object of the present invention is to provide a die for extruding a fine multi-hole tube that can suppress the lack of a partition wall and can reduce the width of a hollow portion.
[0011]
Another object of the present invention is to provide a mandrel for use in the die for extruding a fine multi-hole tube.
[0012]
Still another object of the present invention is to provide a multi-hole tube manufactured using the fine die for extruding a fine multi-hole tube.
[0013]
Still another object of the present invention is to provide a method for producing a heat exchange tube using the die.
[0014]
Still another object of the present invention is to provide a heat exchanger using the heat exchange tube and a method of manufacturing the heat exchanger.
[0015]
[Means for Solving the Problems]
In the present invention, the pocket portion is formed in the thickness direction of the columnar body of the mandrel of the extrusion die, and the shape of the pocket portion is devised.
[0016]
That is, the present invention is as follows.
(1) A die female die that forms the outer periphery of the pipe, and a mandrel combined with the female die,
The mandrel has a main body and a plurality of columnar bodies that protrude from the main body in a comb-like shape and are arranged at intervals in the width direction, and the tip outer periphery of the columnar body is arranged in the width direction of the tube. It is a bearing part that forms the inner peripheral surface of a plurality of hollow parts provided,
At least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion on the rear side in the extrusion direction from the bearing portion, so that at least one side in the thickness direction of the columnar body. In addition, a pocket portion that is a space for filling a molding material is formed,
In addition, the surface extending from the base end portion of the columnar body to the pocket portion is formed as an inclined surface or curved surface for promoting introduction of the molding material into the pocket portion, while the surface extending from the pocket portion to the bearing portion is inward. A die for extruding a fine multi-hole tube, wherein the die is formed on a convex curved surface.
(2) The die for extruding a fine multi-hole tube according to item 1 above, wherein a reinforcing rib protrudes from the tip surface of the columnar body.
(3) The die for extruding a fine multi-hole tube according to the above item 1 or 2, wherein the width of the columnar body in the bearing portion is 2.0 mm or less, and the interval between the bearing portions of adjacent columnar bodies is 0.6 mm or less.
(4) The die for extruding a fine multi-hole tube according to any one of the preceding items 1 to 3, wherein a groove is formed on at least one surface in the thickness direction of the columnar body in the bearing portion.
(5) a mandrel combined with a female die that forms the outer periphery of the tube,
A plurality of columnar bodies protruding from the main body in a comb-like shape and arranged at intervals in the width direction, and a plurality of the outer peripheral portions of the columnar bodies arranged in the width direction of the tube; It is a bearing part that forms the inner peripheral surface of each hollow part,
At least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion on the rear side in the extrusion direction from the bearing portion, so that at least one side in the thickness direction of the columnar body. In addition, a pocket portion that is a space for filling a molding material is formed,
In addition, the surface extending from the base end portion of the columnar body to the pocket portion is formed as an inclined surface or curved surface for promoting introduction of the molding material into the pocket portion, while the surface extending from the pocket portion to the bearing portion is inward. A mandrel used for a die for extruding a fine multi-hole tube, characterized in that the mandrel is formed on a convex curved surface.
(6) The mandrel as described in (5) above, wherein a reinforcing rib protrudes from the tip surface of the columnar body.
(7) The mandrel according to item 5 or 6 above, wherein the width of the columnar body in the bearing portion is 2.0 mm or less, and the interval between the bearing portions of adjacent columnar bodies is 0.6 mm or less.
(8) The die for extruding a fine multi-hole tube according to any one of the preceding items 5 to 7, wherein a groove is formed on at least one surface in the thickness direction of the columnar body in the bearing portion.
(9) A die for extrusion comprising a die female die that forms the outer periphery of the pipe, and a mandrel combined with the die female die,
The mandrel has a main body and a plurality of columnar bodies that protrude from the main body in a comb-like shape and are arranged at intervals in the width direction, and the tip outer periphery of the columnar body is arranged in the width direction of the tube. It is a bearing part that forms the inner peripheral surface of a plurality of hollow parts provided,
At least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion on the rear side in the extrusion direction from the bearing portion, so that at least one side in the thickness direction of the columnar body. In addition, a pocket portion that is a space for filling a molding material is formed,
In addition, the surface extending from the base end portion of the columnar body to the pocket portion is formed as an inclined surface or curved surface for promoting introduction of the molding material into the pocket portion, while the surface extending from the pocket portion to the bearing portion is inward. An extrusion die formed on a convex curved surface;
A multi-hole tube having a large number of fine hollow portions that are manufactured by using a partition wall and partitioned by a partition wall in the width direction.
(10) The fine multi-hole tube as described in (9) above, wherein a reinforcing rib protrudes from the tip end surface of the columnar body of the extrusion die.
(11) The fine multi-hole tube according to 9 or 10 above, wherein the width of the hollow portion is 2.0 mm or less and the wall thickness of the partition wall is 0.6 mm or less.
(12) The protrusions are formed between adjacent partition walls in the hollow portion by forming a groove portion on at least one surface in the thickness direction of the columnar body in the bearing portion of the extrusion die. The fine multi-hole tube according to any one of the above.
(13) A die female die that forms the outer periphery of the pipe and a mandrel combined with the die female die, the mandrel projecting from the main body into a comb-like shape and spaced apart in the width direction. A plurality of columnar bodies provided, and a tip outer peripheral portion of the columnar body serves as a bearing portion forming an inner peripheral surface of a plurality of hollow portions arranged in the width direction of the tube, and the bearing portion Further, on the rear side in the extrusion direction, at least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion, thereby forming at least one side in the thickness direction of the columnar body. A pocket portion, which is a material filling space, is formed, and a surface continuing from the base end portion of the columnar body to the pocket portion is formed as an inclined surface or a curved surface for promoting introduction of the molding material into the pocket portion. Meanwhile, pocket Using the extrusion die of the side next to the bearing portion is formed on the curved surface of the inner convex from parts,
A method for producing a heat exchange tube, comprising extruding a molding material from the extrusion die.
(14) The method for producing a heat exchange tube as described in (13) above, wherein a reinforcing rib is protruded from the front end surface of the columnar body of the extrusion die.
(15) The width of the columnar body in the bearing portion of the extrusion die is 2.0 mm or less, and the interval between the bearing portions of adjacent columnar bodies is 0.6 mm or less. Production method.
(16) The method for producing a heat exchange tube according to any one of items 13 to 15, wherein a groove is formed on at least one surface in the thickness direction of the columnar body in the bearing portion of the extrusion die.
(17) An extrusion die including a die female die that forms an outer peripheral portion of a pipe, and a mandrel combined with the die female die,
The mandrel has a main body and a plurality of columnar bodies that protrude from the main body in a comb-like shape and are arranged at intervals in the width direction, and the tip outer periphery of the columnar body is arranged in the width direction of the tube. It is a bearing part that forms the inner peripheral surface of a plurality of hollow parts provided,
At least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion on the rear side in the extrusion direction from the bearing portion, so that at least one side in the thickness direction of the columnar body. In addition, a pocket portion that is a space for filling a molding material is formed,
In addition, the surface extending from the base end portion of the columnar body to the pocket portion is formed as an inclined surface or curved surface for promoting introduction of the molding material into the pocket portion, while the surface extending from the pocket portion to the bearing portion is inward. An extrusion die formed on a convex curved surface;
A heat exchanger provided with a heat exchange tube having a large number of fine hollow portions that are manufactured by using and partitioned by a partition wall in the width direction.
(18) The heat exchanger as described in (17) above, wherein a reinforcing rib protrudes from the tip end surface of the columnar body of the extrusion die.
(19) The heat exchanger according to item 17 or 18 above, wherein the hollow portion of the heat exchange tube has a width of 2.0 mm or less and the partition wall has a thickness of 0.6 mm or less.
(20) The heat exchanger according to any one of items 17 to 19, wherein a fin portion protrudes between adjacent partition walls in the hollow portion of the heat exchange tube.
(21) An extrusion die comprising a die female die that forms the outer periphery of a pipe, and a mandrel combined with the die female die,
The mandrel has a main body and a plurality of columnar bodies that protrude from the main body in a comb-like shape and are arranged at intervals in the width direction, and the tip outer periphery of the columnar body is arranged in the width direction of the tube. It is a bearing part that forms the inner peripheral surface of a plurality of hollow parts provided,
At least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion on the rear side in the extrusion direction from the bearing portion, so that at least one side in the thickness direction of the columnar body. In addition, a pocket portion that is a space for filling a molding material is formed,
In addition, the surface extending from the base end portion of the columnar body to the pocket portion is formed as an inclined surface or curved surface for promoting introduction of the molding material into the pocket portion, while the surface extending from the pocket portion to the bearing portion is inward. An extrusion die formed on a convex curved surface;
Using a heat exchange tube having a large number of fine hollow portions that are manufactured by using a partition wall in the width direction,
A method of manufacturing a heat exchanger in which the heat exchange tubes and outer fins are alternately arranged and brazed.
(22) The method for producing a heat exchanger as described in (21) above, wherein a reinforcing rib is projected and formed on the front end surface of the columnar body of the extrusion die.
(23) The method for producing a heat exchanger as described in 21 or 22 above, wherein the width of the hollow part of the heat exchange tube is 2.0 mm or less and the wall thickness of the partition wall is 0.6 mm or less.
(24) The method for manufacturing a heat exchanger according to any one of the above items 21 to 23, wherein the fin portion protrudes between adjacent partition walls in the hollow portion of the heat exchange tube.
[0017]
In other words, a first aspect of the present invention includes a female die that forms the outer periphery of a pipe, and a mandrel combined with the female die, and the mandrel protrudes from the main body into a comb-like shape. A plurality of columnar bodies arranged at intervals in the width direction, and an outer peripheral portion of the tip of the columnar body forms an inner peripheral surface of a plurality of hollow portions arranged in the width direction of the pipe. The thickness of the columnar body is such that at least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion on the rear side in the extrusion direction from the bearing portion. A pocket portion, which is a molding material filling space, is formed on at least one side of the direction, and a surface continuing from the base end portion of the columnar body to the pocket portion is for promoting introduction of the molding material into the pocket portion. On inclined or curved surfaces While it made, in fine multihole pipe extrusion die, wherein the surface subsequent to the bearing portion from the pocket portion is formed on the curved surface of the inner convex.
[0018]
In this fine multi-hole tube extrusion die, a pocket portion, which is a space for filling a molding material, is formed on at least one side in the thickness direction of the columnar body of the mandrel, and continues from the base end portion of the columnar body to the pocket portion. Since the surface is formed as an inclined surface or curved surface for promoting introduction of the molding material into the pocket portion, the molding material smoothly flows into the pocket portion and is filled during extrusion. For this reason, a sufficient amount of the molding material is supplied to the gap between the bearing portions of the adjacent columnar bodies. As a result, even if the clearance between the bearing portions is reduced, the lack of the partition wall of the pipe is suppressed. In addition, since it is not always necessary to provide the widthwise pocket portion of the columnar body by reducing the widthwise thickness of the columnar body, the width of the columnar body in the bare link portion can be reduced accordingly, and the hollow portion of the tube The width can be reduced.
[0019]
In addition, since the surface from the pocket part to the bearing part is an inwardly curved surface, there is no corner in this part, and stress concentration on the corner due to the extrusion pressure applied to the columnar body can be avoided. The damage to the columnar body is suppressed.
[0020]
In addition, by providing the pocket portion on at least one side in the thickness direction of the columnar body of the mandrel, the thickness in the thickness direction of the columnar body is reduced, and the strength is reduced accordingly. For this reason, it is good also as what aims at the strength improvement of a mandrel as a structure by which the reinforcement rib protruded and formed in the front end surface of the columnar body.
[0021]
Moreover, it is preferable that the width of the columnar body in the bearing portion is 2.0 mm or less, and the interval between the bearing portions of adjacent columnar bodies is 0.6 mm or less, from the viewpoint that the effect of the present invention can be particularly exhibited.
[0022]
Moreover, it is good also as a structure by which the groove part is formed in the at least single side | surface of the thickness direction of the columnar body in a bearing part. In this case, since the protrusion corresponding to the groove is formed in the multi-hole tube, for example, when the multi-hole tube is used as a heat exchange tube of a heat exchanger, this protrusion is used as a refrigerant flowing through the hollow portion. It can be used as an inner fin for increasing the contact area.
[0023]
According to a second aspect of the present invention, there is provided a mandrel combined with a female die for forming an outer peripheral portion of a pipe, and a plurality of a mandrel protruding in a comb shape from the main body and spaced in the width direction. Each of the columnar bodies is a bearing portion that forms inner circumferential surfaces of a plurality of hollow portions arranged in the width direction of the tube. On the rear side, at least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion, so that the space for filling the molding material is provided on at least one side in the thickness direction of the columnar body. And the surface following the pocket portion from the base end portion of the columnar body is formed as an inclined surface or curved surface for promoting introduction into the pocket portion of the molding material, while the pocket portion From the Bearin The side next to the part is in a mandrel for use in fine multihole pipe extrusion die, characterized in that it is formed on the curved surface of the inner convex.
[0024]
By combining this mandrel with a female die, it is possible to obtain a multi-hole tube having a narrow hollow portion without a lack of partition wall.
[0025]
Also in this mandrel, it is good also as a structure by which the reinforcement rib protrudes and formed in the front end surface of the columnar body from a viewpoint of an intensity | strength improvement. Moreover, the width | variety of the columnar body in a bearing part may be 2.0 mm or less, and the space | interval between the bearing parts of an adjacent columnar body may be 0.6 mm or less. Moreover, it is good also as a structure by which the groove part is formed in the at least single side | surface of the thickness direction of the columnar body in a bearing part.
[0026]
According to a third aspect of the present invention, there is provided a female die that forms an outer peripheral portion of a tube, and a mandrel combined with the female die, and the mandrel projects in a comb-like shape from the main body and extends in the width direction. A plurality of columnar bodies arranged at intervals to each other, the outer peripheral portion of the columnar body forming an inner peripheral surface of a plurality of hollow portions arranged in the width direction of the tube And at least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion on the rear side in the extrusion direction with respect to the bearing portion. A pocket portion, which is a molding material filling space, is formed on at least one surface side, and a surface continuing from the base end portion of the columnar body to the pocket portion is an inclined surface for promoting introduction of the molding material into the pocket portion. Or formed into a curved surface On the other hand, it is manufactured using an extrusion die in which a surface following the bearing portion from the pocket portion is formed as an inwardly convex curved surface, and has a large number of fine hollow portions partitioned by a partition wall in the width direction. It is in the hole tube.
[0027]
In this multi-hole tube, the width of the hollow portion where the partition wall is not thin can be made small.
[0028]
In this multi-hole tube, a reinforcing rib may protrude from the end face of the columnar body of the extrusion die, the width of the hollow portion of the multi-hole tube is 2.0 mm or less, and the wall thickness of the partition wall is It may be 0.6 mm or less. Moreover, the protrusion part may be formed between the adjacent partition walls in a hollow part by forming the groove part in at least one surface of the thickness direction of the columnar body in the bearing part of the extrusion die.
[0029]
According to a fourth aspect of the present invention, there is provided a female die that forms an outer peripheral portion of a pipe, and a mandrel combined with the female die, and the mandrel projects in a comb-like shape from the main body and extends in the width direction. A plurality of columnar bodies arranged at intervals to each other, the outer peripheral portion of the columnar body forming an inner peripheral surface of a plurality of hollow portions arranged in the width direction of the tube And at least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion on the rear side in the extrusion direction with respect to the bearing portion. A pocket portion, which is a molding material filling space, is formed on at least one surface side, and a surface continuing from the base end portion of the columnar body to the pocket portion is an inclined surface for promoting introduction of the molding material into the pocket portion. Or formed into a curved surface On the other hand, a method for producing a heat exchange tube is characterized by using an extrusion die in which a surface following the bearing portion from the pocket portion is formed as an inwardly convex curved surface, and extruding a molding material from the extrusion die. It is in.
[0030]
According to this manufacturing method, it is possible to manufacture a heat exchange tube having a small hollow portion without a lack of partition wall.
[0031]
Also in this manufacturing method, the reinforcing ribs may be formed to protrude from the front end surface of the columnar body of the extrusion die, and the width of the columnar body in the bearing portion of the extrusion die is 2.0 mm or less, and adjacent columnar shapes The interval between the bearing portions of the body may be 0.6 mm or less, and a groove portion may be formed on at least one surface in the thickness direction of the columnar body in the bearing portion of the extrusion die.
[0032]
According to a fifth aspect of the present invention, there is provided an extrusion die including a die female die that forms an outer peripheral portion of a pipe, and a mandrel combined with the die female die,
The mandrel has a main body and a plurality of columnar bodies that protrude from the main body in a comb-like shape and are arranged at intervals in the width direction, and the tip outer periphery of the columnar body is arranged in the width direction of the tube. It is a bearing part that forms the inner peripheral surface of a plurality of hollow parts provided,
At least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion on the rear side in the extrusion direction from the bearing portion, so that at least one side in the thickness direction of the columnar body. In addition, a pocket portion that is a space for filling a molding material is formed,
In addition, the surface extending from the base end portion of the columnar body to the pocket portion is formed as an inclined surface or curved surface for promoting introduction of the molding material into the pocket portion, while the surface extending from the pocket portion to the bearing portion is inward. An extrusion die formed on a convex curved surface;
And a heat exchanger having a heat exchange tube having a large number of fine hollow portions partitioned by a partition wall in the width direction.
[0033]
In this heat exchanger, the partition wall is provided with a heat exchange tube having a small hollow portion without a lack of wall, so that the heat exchange efficiency of the heat exchange tube and thus the heat exchange efficiency of the entire heat exchanger can be improved.
[0034]
Also in this heat exchanger, a reinforcing rib may protrude from the tip end surface of the columnar body of the extrusion die, the width of the hollow portion of the heat exchange tube is 2.0 mm or less, and the wall thickness of the partition wall 0.6mm or less may be sufficient, and the fin part may be protrudingly formed between the adjacent partition walls in the hollow part of a heat exchange tube.
[0035]
The sixth of the present invention is an extrusion die comprising a die female die that forms the outer periphery of the pipe, and a mandrel combined with the female die.
The mandrel has a main body and a plurality of columnar bodies that protrude from the main body in a comb-like shape and are arranged at intervals in the width direction, and the tip outer periphery of the columnar body is arranged in the width direction of the tube. It is a bearing part that forms the inner peripheral surface of a plurality of hollow parts provided,
At least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion on the rear side in the extrusion direction from the bearing portion, so that at least one side in the thickness direction of the columnar body. In addition, a pocket portion that is a space for filling a molding material is formed,
In addition, the surface extending from the base end portion of the columnar body to the pocket portion is formed as an inclined surface or curved surface for promoting introduction of the molding material into the pocket portion, while the surface extending from the pocket portion to the bearing portion is inward. An extrusion die formed on a convex curved surface;
Using a heat exchange tube having a large number of fine hollow portions that are manufactured by using a partition wall in the width direction,
This heat exchanger tube and outer fin are alternately disposed in a heat exchanger manufacturing method for brazing.
[0036]
In this manufacturing method, since the heat exchange tube with a small hollow part width without a lacking wall is used in the partition wall, it becomes possible to manufacture a heat exchanger excellent in the heat exchange efficiency of the heat exchange tube and thus the overall heat exchange efficiency. .
[0037]
Also in this heat exchanger manufacturing method, a reinforcing rib may protrude from the end face of the columnar body of the extrusion die, the width of the hollow portion of the heat exchange tube is 2.0 mm or less, and the partition wall The wall thickness of the heat exchanger tube may be 0.6 mm or less, and the fin portion may be formed to project between adjacent partition walls in the hollow portion of the heat exchange tube.
[0038]
DETAILED DESCRIPTION OF THE INVENTION
In the embodiment described below, as shown in FIGS. 7A and 7B, a multi-hole tube to be subjected to extrusion processing has a large number of minute hollow portions 102 arranged in the width direction via a partition wall 101. It is a flat tube 100 made of aluminum (including its alloy) and used for a heat exchange tube for circulating a refrigerant in a heat exchanger. And in the opposite wall part of the thickness direction (up-and-down direction of Drawing 7) of this aluminum tube, in the position of the width direction central part of each hollow part except the hollow part of the width direction (left-and-right direction of Drawing 7) both sides, Fin portions 103 each projecting to a midway position toward the opposing wall portion are integrally formed along the length direction of the aluminum tube 100. Therefore, the cross-sectional shape of each of the hollow portions excluding the hollow portions on both sides in the width direction is H-shaped.
[0039]
FIG. 1 is a perspective view showing a mandrel 2 of an extrusion die 1 according to an embodiment of the present invention, FIG. 2 is a front view of the female die 3 as seen from the rear (entry side) in the extrusion direction, and FIG. FIG. 4 is a cross-sectional view taken along the line III-III in FIG. 1 in a state where the die 3 and the mandrel 2 are combined, and FIG. 4 is a cross-sectional view taken along the line IV-IV in FIG.
[0040]
1 to 4, the die female die 3 has a flat opening 31 corresponding to the outer peripheral shape of the aluminum tube at the center of the rear surface in the extrusion direction, and communicates with the opening 31. An extruded material passage hole 32 penetrating the axial direction of the die die 3 is formed. A bare link portion 33 that defines the outer peripheral surface of the aluminum tube is formed at the edge of the opening 31.
[0041]
On the other hand, the mandrel 2 has a flat mandrel main body 21 and a plurality of mandrel main bodies 21 that protrude integrally from the tip of the mandrel main body 21 in a comb shape and are arranged at intervals in the width direction (left-right direction in FIG. 4). And a columnar body 22.
[0042]
The connecting portion 23 of the mandrel main body 21 with the columnar body 22 is an inclined surface in which both outer surfaces in the thickness direction (vertical direction in FIG. 4) taper toward the tip. The molding material on both sides in the thickness direction is easy to flow toward the columnar body 22.
[0043]
The columnar body 22 is for forming the hollow portion 102 of the aluminum tube 100, and the shape of the tip portion thereof corresponds to the cross-sectional shape of each hollow portion 102. That is, in each columnar portion 22 excluding the columnar portions 22a on both sides in the row direction, the groove portion 24 for forming the fin portion 103 of the aluminum tube 100 is formed at the middle in the thickness direction at the center of both surfaces in the thickness direction. Accordingly, each columnar portion 22 is formed in an H-shaped cross section corresponding to the cross-sectional shape of the hollow portion 102 of the aluminum tube 100. The groove 24 extends to the vicinity of the base end of the columnar body 22. Further, the outer peripheral portion of the tip of the columnar body 22 is a bearing portion 25 that defines the inner peripheral surface of the hollow portion of the aluminum tube 100.
[0044]
On the rear side in the extrusion direction of the bare link portion 25, both side surfaces in the thickness direction of the columnar body 22 are cut inward from the position of the bearing portion 25 and are recessed, and this portion is filled with a molding material. A pocket portion 27 as a space is formed.
[0045]
Further, as shown in detail in FIG. 3, a surface 28 extending from the base end portion of the columnar body 22 to the pocket portion 27 is an inclined surface, which can facilitate introduction of the molding material into the pocket portion 27. It has been. In addition, you may form in the curved surface which can accelerate | stimulate the introduction to the pocket part 27 of a molding material instead of an inclined surface.
[0046]
On the other hand, a surface 29 following the bearing portion 25 from the pocket portion 27 is formed as an inwardly convex curved surface. The curved surface is formed in this way in order to eliminate the occurrence of corners on the surface 29 following the bearing portion 25 from the pocket portion 27, and stress is concentrated on the corner portions during extrusion, and the columnar body 22 is damaged. This is to prevent this.
[0047]
Further, in this embodiment, the width of the columnar body 22 is the same from the base end portion to the bearing portion 25, and a flat surface without a step until both side surfaces 26 in the width direction reach the bearing portion. Is formed. In addition, it is good also as a structure which protruded the bearing part 25 of the columnar body 22 in the width direction. In this case, stepped portions from both side surfaces in the width direction of the columnar body 22 to the bearing portion may be formed on the curved surface in the same manner as the thickness direction. In addition, when there is a margin in the width of the columnar body 22, a pocket portion may be provided between adjacent columnar bodies.
[0048]
In the mandrel 2 having the above-described configuration, the front end of the columnar body 22 faces the opening 31 of the female die 3 so that the bearing portion 25 at the front end of the columnar body 22 faces the bearing portion 33 of the female die 3. The dice 1 are configured. In addition, the mandrel 2 may be combined with a die female die in a state where it is fixedly supported by a shrink fit or the like on a support body (not shown) as necessary. Further, the mandrel 2 may be divided into, for example, a mandrel main body 21 and a columnar body 22 and fixed by shrink fitting or the like.
[0049]
In this state, an aluminum billet as a molding material is loaded into a container (not shown) in which the die 1 is set, and extrusion is performed according to a conventional method. By pressing, the aluminum molding material flows on both sides in the thickness direction of the mandrel 2 in the direction of the columnar body 22 along the inclined surface of the continuous portion 23 of the mandrel main body 21 and the columnar body 22 as shown by arrows in FIG. The pocket portions 27 formed on both sides of the columnar body 22 in the thickness direction are filled.
[0050]
When the pressing is further applied, the molding material filled in the pocket portion is pushed out from the gap 11 between the bearing portion 25 of the columnar body 22 and the bearing portion 33 of the die female die, and at the same time, between the adjacent columnar bodies 22. It is sufficiently supplied in between and pushed out from the gap 12 between the bearing portions 25 of the adjacent columnar bodies 22. Then, by continuously extruding the molding material from the

gaps

11 and 12, the aluminum extruded tube 100 having a cross-sectional shape as shown in FIG. 7 is manufactured.
[0051]
During this extrusion, the bearing portions 25 of the respective columnar bodies 22 are subjected to stress from the back to the front in the extrusion direction through the molding material filled in the pocket portions 27, but are continuous from the pocket portions 27 to the bearing portions 25. Since 29 is formed on a curved surface and there is no corner, the stress is dispersed, and damage to the columnar body is suppressed.
[0052]
In the extrusion die according to this embodiment, pocket portions 27 are formed on both sides of the columnar body 22 in the thickness direction, and no pocket portions are provided between the columnar bodies 22. For this reason, compared with the case where the width of each columnar body 22 is reduced in order to form the pocket portion, the width of the bearing portion of each columnar body can be reduced, and therefore the width of the hollow portion 102 of the aluminum tube can be reduced. Can be small.
[0053]
In addition, since the pocket portion 27 is provided in the thickness direction of the columnar body 22, the molding material is sufficiently supplied to the gap 12 in the width direction between adjacent columnar bodies as in the case where the pocket portion is provided in the width direction of the columnar body. Even if the gap 12 is reduced, it is possible to suppress the occurrence of a lack of thickness in the partition wall 101 of the aluminum tube 100.
[0054]
Specifically, as shown in FIG. 1B, the width W of the columnar body 22 in the bearing portion 25 is set to 2.0 mm or less, and the gap G between the bearing portions of the adjacent

columnar bodies

22 and 22 is 0. The effect is large when it is set to 6 mm or less. That is, an effective effect is exhibited when manufacturing the extruded aluminum tube 100 in which the thickness T1 of the partition wall 101 is 0.6 mm or less and the width W1 of the hollow portion 102 is 2.0 mm or less.
[0055]
FIG. 5 shows a modification of the present invention. In this modification, two reinforcing ribs 50 project from the front end surface of each columnar body 22 in the H shape when viewed from the front along the long side portion of the “H” shape. Thereby, the columnar body 22 can be strengthened against the back pressure applied to the bearing portion 33 of the columnar body 22 during extrusion (indicated by an arrow in FIG. 5C).
[0056]
Moreover, in the above embodiment, the case where the columnar body of the mandrel 2 is formed in the cross section H shape and the aluminum tube 100 having the hollow portion 102 having the cross section H shape is pushed out is shown, but as shown in FIG. It is good also as a structure which forms in the rectangular columnar body 22 and extrudes the aluminum tube 200 which many rectangular hollow parts 202 as shown in FIG. In FIG. 6, reference numeral 50 denotes a protruding reinforcing rib provided on the front end surface of the columnar body 22 as necessary.
[0057]
FIG. 9 is a front view showing a parallel flow condenser as a heat exchanger using the above-described

aluminum tube

100 or 200 as a heat exchange tube 250.
[0058]
In this condenser, heat exchange tubes 250 made of

aluminum tubes

100 and 200 and corrugated outer fins 251 made of aluminum are alternately arranged up and down, and both ends of the heat exchange tubes 250 have a pair of

aluminum headers

252, 252 is connected. The heat exchange tube 250 and the header 252 are brazed, and the heat exchange tube 250 and the outer fin 251 are also brazed.
[0059]
In FIG. 9, 253 is a refrigerant inlet, 254 is the same outlet, 255 is a pair of side plates arranged outside the outermost outer fin, and 256 is a meandering passage made of a heat exchange tube. Therefore, it is a partition that divides the inside of each header 252, and each of these heat exchanger components is also joined to the corresponding portion by brazing.
[0060]
In this heat exchanger, since the

aluminum tube

100 or 200 having a small hollow portion and a thin partition wall is used as the heat exchange tube 250, the heat exchange efficiency is excellent. In particular, when the aluminum tube 100 is used as the heat exchange tube 250, the fin portion protruding between adjacent partition walls functions as an inner fin, so that the heat exchange efficiency is further improved.
[0061]
【Example】
In order to show the effect when using the die according to this embodiment, the following tests were conducted.
Example 1
As shown in FIG. 8, a mandrel 2 having a columnar body 22 having a rectangular cross section as shown in FIG. 6 is provided as a die 1 for extruding an aluminum tube 200 in which hollow portions 102 having a rectangular cross section as shown in FIG. A die according to a conventional product in which a pocket portion is formed between adjacent columnar bodies 22 in the width direction of the present invention, and a product according to the present invention in which pocket portions 27 are formed on both sides in the thickness direction without forming a pocket portion in the width direction. A die according to was used as a sample. However, the reinforcing rib 50 at the tip of the columnar body 22 was not provided.
[0062]
Then, the width G2 of the columnar body 22 (shown in FIG. 6) and the size G2 of the gap 12 between the adjacent columnar bodies 22 in a state where the height H of the bare link portion 25 of the columnar body 22 is constant at 1.5 mm. Was set to various values as shown in Table 1, and aluminum billets were extruded to examine the limit of extrusion moldability. The results are shown in Table 1 and FIG. 10, the vertical axis represents the size G2 of the gap 12 between the adjacent columnar bodies 22, and the horizontal axis represents the width W2 of the columnar body 22. Also, the line connecting the black square points indicates the extrusion limit of the conventional product, the line connecting the black circle points indicates the extrusion limit of the implemented product, and the upper right area surrounded by each line is a range where good extrusion can be performed , And the lower left region indicates a range where extrusion is poor or difficult.
[0063]
[Table 1]

[0064]
As can be seen from Table 1 and FIG. 10, in the conventional product in which the pocket portion is formed in the width direction of the mandrel 22, when the width W2 of the columnar body is 2.0 mm, the gap G2 is set to 0.1 mm. Insufficient meat or the columnar body itself was damaged. Further, when the width W2 of the columnar body 22 is 1.0 mm, 0.8 mm, 0.5 mm, and 0.25 mm, the gap G2 becomes 0.13 mm, 0.15 mm, 0.22 mm, and 0.6 mm, respectively. The partition wall 201 was thinned or the columnar body itself was damaged. On the other hand, in the embodiment of the present invention in which the pocket portion is formed in the thickness direction of the mandrel, if the width W2 of the columnar body 22 is 0.2 mm or more and the gap G2 is 0.08 mm or more, The columnar body 22 was not damaged. In addition, when the width W2 of the columnar body 22 is 0.15 mm, 0.1 mm, and 0.05 mm, even if the gap G2 is 0.10 mm, 0.18 mm, and 0.6, respectively, There was no breakage of the thin wall or the columnar body 22.
[0065]
Therefore, according to the product of the present invention, it has been confirmed that the extrusion molding limit can be raised.
[0066]
In addition, in the shaded part of FIG. 10, it was difficult to extrude even this product.
(Example 2)
Using a mandrel of the same type as in Example 1, a die according to a conventional product in which a pocket portion is formed between adjacent columnar bodies 22 in the width direction of the mandrel 2, and without forming a pocket portion in the width direction, A die according to the product of the present invention in which pocket portions were formed on both sides was used as a specimen. The reinforcing rib 50 at the tip of the columnar body was not provided.
[0067]
Then, in a state where the height H of the bare link portion 25 of the columnar body 22 is 0.7 mm and the size G2 of the gap 12 between the adjacent columnar bodies 22 is constant 0.2 mm, the width W2 of the columnar body 22 is 0. The aluminum billet was extruded by setting to 5 mm, 0.8 mm, and 1.0 mm, respectively, and the life of the die was investigated.
[0068]
As a result, when the width W2 of the columnar body 22 is 0.5 mm, in the conventional product, the die life is reached when the billet of 0.9 ton is pushed out, whereas in the present product, 2.1 ton, The service life of the product was about 2.3 times that of the conventional product. In addition, when the width W2 of the columnar body 22 is 0.8 mm, the extrusion amount until the end of its service life is 1.5 tons in the conventional product, whereas this product is 2.5 tons, which is about the same as the conventional product. The lifetime was 1.6 times. In addition, when the width W2 of the columnar body 22 is 1.0 mm, the extrusion amount until the end of the life of the conventional product is 2.2 tons, whereas this product is 2.6 tons, which is about the same as the conventional product. 1.18 times longer life.
[0069]
Thus, according to the product of the present invention, it has been confirmed that the life can be extended as compared with the conventional product, and in particular, the life can be remarkably extended when the width W2 of the columnar body 22 is set to be small.
[0070]
【The invention's effect】
As described above, a die female die that forms the outer periphery of the pipe and a mandrel combined with the die female die are provided. The mandrel protrudes from the main body in a comb-like shape and is spaced in the width direction. A plurality of columnar bodies arranged in a row, the outer peripheral portion of the tip of the columnar body is a bearing portion that forms the inner peripheral surface of a plurality of hollow portions arranged in the width direction of the tube, At least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion on the rear side in the extrusion direction from the bearing portion, so that at least one surface side in the thickness direction of the columnar body. The pocket portion, which is a space for filling the molding material, is formed, and the surface continuing from the base end portion of the columnar body to the pocket portion is formed as an inclined surface or a curved surface for promoting introduction of the molding material into the pocket portion. On the other hand According to the fine multi-hole tube extrusion die characterized in that the surface following the bearing portion from the pocket portion is formed as an inwardly convex curved surface, the molding material smoothly flows into the pocket portion during extrusion. Therefore, a sufficient amount of the molding material is supplied to the gap between the bearing portions of the adjacent columnar bodies.
[0071]
As a result, even if the clearance between the bearing portions is reduced, the lack of the partition wall of the pipe is suppressed. In addition, since it is not always necessary to provide the widthwise pocket portion of the columnar body by reducing the widthwise thickness of the columnar body, the width of the columnar body in the bare link portion can be reduced accordingly, and the hollow portion of the tube The width can be reduced.
[0072]
In addition, since the surface from the pocket part to the bearing part is an inwardly curved surface, there is no corner in this part, and stress concentration on the corner due to the extrusion pressure applied to the columnar body can be avoided. The damage to the columnar body is suppressed.
[0073]
In the extrusion die, when the reinforcing rib protrudes from the tip surface of the columnar body, the strength of the mandrel can be improved.
[0074]
Moreover, according to the said extrusion die, the width | variety of the columnar body in a bearing part is 2.0 mm or less, and the extrusion of the fine multi-hole pipe whose space | interval between the bearing parts of an adjacent columnar body is 0.6 mm or less is also possible. become.
[0075]
Further, in the case where a groove is formed on at least one surface in the thickness direction of the columnar body in the bearing portion, since the protrusion corresponding to the groove is formed in the multi-hole tube, for example, the multi-hole tube is replaced with a heat exchanger. When this heat exchange tube is used, this protrusion can be used as an inner fin for increasing the contact area with the refrigerant flowing through the hollow portion.
[0076]
Also, a mandrel combined with a female die that forms the outer periphery of a tube, and having a main body and a plurality of columnar bodies that protrude from the main body in a comb shape and are arranged at intervals in the width direction. The outer peripheral part of the tip of the columnar body is a bearing part that forms the inner peripheral surface of a plurality of hollow parts arranged in the width direction of the tube, and the columnar body is located on the rear side in the extrusion direction with respect to the bearing part. When the outer surface of at least one side in the thickness direction is recessed inward in the thickness direction from the position of the bearing portion, a pocket portion that is a space for filling a molding material is formed on at least one side in the thickness direction of the columnar body. The surface extending from the base end portion of the columnar body to the pocket portion is formed as an inclined surface or curved surface for promoting introduction of the molding material into the pocket portion, while the surface continuing from the pocket portion to the bearing portion. Is inward According to the mandrel used in the die for extruding a fine multi-hole tube, characterized in that it is formed on the curved surface of the die, in combination with a female die, the hollow part without a lack of wall in the partition wall has a small width. A hole tube can be obtained.
[0077]
In this mandrel, the strength can be improved when the reinforcing rib protrudes from the tip surface of the columnar body.
[0078]
In addition, when the width of the columnar body in the bearing portion is 2.0 mm or less and the interval between the bearing portions of adjacent columnar bodies is 0.6 mm or less, the hollow portion of the multi-hole tube is made extremely fine. can do.
[0079]
Moreover, when the groove part is formed in at least one surface of the thickness direction of the columnar body in the bearing part, this protrusion part can be used as an inner fin of a heat exchange tube, for example.
[0080]
Also, a female die for forming the outer periphery of the tube and a mandrel combined with the female die are provided. The mandrel protrudes in a comb-like shape from the main body and is arranged in rows at intervals in the width direction. A plurality of columnar bodies, the outer peripheral portion of the columnar body being a bearing portion that forms inner peripheral surfaces of a plurality of hollow portions arranged in the width direction of the tube, Also, on the rear side in the extrusion direction, at least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion, thereby forming a molding material on at least one side in the thickness direction of the columnar body. A pocket portion that is a filling space is formed, and a surface that continues from the base end portion of the columnar body to the pocket portion is formed as an inclined surface or a curved surface for promoting introduction of the molding material into the pocket portion. ,pocket According to the multi-hole tube having a large number of fine hollow portions that are manufactured using an extrusion die in which the surface following the bearing portion is formed as an inwardly convex curved surface and partitioned by a partition wall in the width direction In addition, a multi-hole tube with a small width of the hollow portion without a lack of partition wall can be formed.
[0081]
In this multi-hole tube, when the reinforcing rib is formed to protrude from the tip end surface of the columnar body of the extrusion die, the lack of the partition wall is further eliminated by the improvement of the strength of the mandrel, and the width of the hollow portion is further increased. You can do with a small multi-hole tube.
[0082]
In addition, when the width of the hollow portion of the multi-hole tube is 2.0 mm or less and the thickness of the partition wall is 0.6 mm or less, the multi-hole has a small width of the hollow portion and a small thickness of the partition wall. You can do with a tube.
[0083]
In addition, when a groove is formed on at least one surface in the thickness direction of the columnar body in the bearing portion of the extrusion die, a protrusion is formed between the adjacent partition walls in the hollow portion. The part can be used as an inner fin of a heat exchange tube, for example.
[0084]
Also, a female die for forming the outer periphery of the tube and a mandrel combined with the female die are provided. The mandrel protrudes in a comb-like shape from the main body and is arranged in rows at intervals in the width direction. A plurality of columnar bodies, the outer peripheral portion of the columnar body being a bearing portion that forms inner peripheral surfaces of a plurality of hollow portions arranged in the width direction of the tube, Also, on the rear side in the extrusion direction, at least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion, thereby forming a molding material on at least one side in the thickness direction of the columnar body. A pocket portion that is a filling space is formed, and a surface that continues from the base end portion of the columnar body to the pocket portion is formed as an inclined surface or a curved surface for promoting introduction of the molding material into the pocket portion. ,pocket According to the heat exchanging tube manufacturing method, the molding material is extruded from the extrusion die, using an extrusion die in which a surface following the bearing portion is formed as an inwardly convex curved surface. It is possible to manufacture a heat exchange tube having a small hollow part with no wall thickness.
[0085]
In this manufacturing method, when the reinforcing rib protrudes from the front end surface of the columnar body of the extrusion die, the lack of the partition wall is further eliminated and the width of the hollow portion is further reduced by improving the mandrel strength. A heat exchange tube can be manufactured.
[0086]
In addition, when the width of the columnar body in the bearing portion of the extrusion die is 2.0 mm or less and the interval between the bearing portions of adjacent columnar bodies is 0.6 mm or less, the width of the hollow portion is 2.0 mm. It is possible to manufacture a heat exchange tube that is as small as below and has a thin wall thickness of 0.6 mm or less.
[0087]
In addition, when a groove is formed on at least one surface in the thickness direction of the columnar body in the bearing portion of the extrusion die, a heat exchange tube in which a fin portion protrudes between adjacent partition walls in the hollow portion is provided. Can be manufactured.
[0088]
Also, an extrusion die comprising a female die that forms the outer periphery of the tube and a mandrel combined with the female die, the mandrel projects in a comb-like shape from the main body and extends in the width direction. A plurality of columnar bodies arranged at intervals to each other, the outer peripheral portion of the columnar body forming an inner peripheral surface of a plurality of hollow portions arranged in the width direction of the tube And at least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion on the rear side in the extrusion direction with respect to the bearing portion. A pocket portion, which is a molding material filling space, is formed on at least one surface side, and a surface continuing from the base end portion of the columnar body to the pocket portion is an inclined surface for promoting introduction of the molding material into the pocket portion. Or curved surface On the other hand, a large number of fine hollow portions, which are manufactured using an extrusion die, in which a surface following the bearing portion from the pocket portion is formed as an inwardly convex curved surface and partitioned by a partition wall in the width direction, According to the heat exchanger equipped with the heat exchange tube, the heat exchange efficiency of the heat exchange tube and thus the heat exchanger as a whole is improved by the heat exchange tube with a narrow hollow part without a lack of partition wall. it can.
[0089]
In this heat exchanger, when the reinforcing rib protrudes from the front end surface of the columnar body of the extrusion die, it is possible to further reduce the lack of the partition wall of the heat exchange tube and further reduce the width of the hollow portion. Furthermore, it can be a heat exchanger with good heat exchange efficiency.
[0090]
In this heat exchanger, when the width of the hollow part of the heat exchange tube is 2.0 mm or less and the wall thickness of the partition wall is 0.6 mm or less, the width of the hollow part of the heat exchange tube is small and the partition wall Since the wall thickness of the heat exchanger is thin, the heat exchange efficiency of the heat exchanger can be improved.
[0091]
Moreover, when the fin part protrudes between adjacent partition walls in the hollow part of the heat exchange tube, the heat exchange efficiency further increases due to the contact between the refrigerant flowing through the heat exchange tube and the fin part.
[0092]
Also, an extrusion die comprising a female die that forms the outer periphery of the tube and a mandrel combined with the female die, the mandrel projects in a comb-like shape from the main body and extends in the width direction. A plurality of columnar bodies arranged at intervals to each other, the outer peripheral portion of the columnar body forming an inner peripheral surface of a plurality of hollow portions arranged in the width direction of the tube And at least one outer surface in the thickness direction of the columnar body is recessed inward in the thickness direction from the position of the bearing portion on the rear side in the extrusion direction with respect to the bearing portion. A pocket portion, which is a molding material filling space, is formed on at least one surface side, and a surface continuing from the base end portion of the columnar body to the pocket portion is an inclined surface for promoting introduction of the molding material into the pocket portion. Or curved surface On the other hand, a large number of fine hollow portions, which are manufactured using an extrusion die, in which a surface following the bearing portion from the pocket portion is formed as an inwardly convex curved surface and partitioned by a partition wall in the width direction, According to the method of manufacturing a heat exchanger in which the heat exchange tubes and outer fins are alternately arranged and brazed using the heat exchange tubes having the heat exchange tubes having a small hollow part width in the partition wall Therefore, it is possible to manufacture a heat exchanger excellent in the heat exchange efficiency of the heat exchange tube, and hence the overall heat exchange efficiency.
[0093]
In this heat exchanger manufacturing method, when the reinforcing rib protrudes from the front end surface of the columnar body of the extrusion die, the lack of the partition wall of the heat exchange tube is further eliminated, and the width of the hollow portion is further reduced. Therefore, a heat exchanger with higher heat exchange efficiency can be manufactured.
[0094]
In addition, when the width of the hollow part of the heat exchange tube is 2.0 mm or less and the wall thickness of the partition wall is 0.6 mm or less, the width of the hollow part of the heat exchange tube is small and the wall thickness of the partition wall is also small. Since it is thin, the heat exchange efficiency of the heat exchanger can be improved.
[0095]
In addition, in the case where the fin portion protrudes between adjacent partition walls in the hollow portion of the heat exchange tube, a heat exchanger with higher heat exchange efficiency can be obtained by contact between the refrigerant flowing through the heat exchange tube and the fin portion. Can be manufactured.
[Brief description of the drawings]
FIG. 1A is a perspective view showing a mandrel of an extrusion die according to an embodiment of the present invention, and FIG. 1B is a plan view of a columnar body.
FIG. 2 is a front view of a female die of the same extrusion die as viewed from the rear (entry side) in the extrusion direction.
FIG. 3 is a cross-sectional view of an essential part of an extrusion die in which a female die and a mandrel are combined.
4 is a cross-sectional view taken along line IV-IV in FIG.
5A and 5B show a modification of the present invention, in which FIG. 5A is a perspective view of a main part of a mandrel, FIG. 5B is a front view of a columnar body viewed from the extrusion side, and FIG. FIG.
FIG. 6 shows another embodiment of the present invention, and is a front view of a main part of a mandrel viewed from the extrusion side.
7A is a sectional perspective view of an extruded aluminum tube manufactured by the dies of FIGS. 1 to 4, and FIG. 7B is an enlarged front sectional view of the same.
8A is a cross-sectional perspective view of an extruded aluminum tube manufactured by a die having the mandrel of FIG. 6, and FIG. 8B is an enlarged front cross-sectional view of the same.
FIG. 9 is a front view of a heat exchanger according to an embodiment of the present invention.
FIG. 10 is a graph showing the results of a limit test of extrudability performed in Examples.
FIG. 11 is a perspective view of a mandrel used in a conventional extrusion die.
[Explanation of symbols]
1. Dice
2 ... Mandrel
21 ... Mandrel body
22 ... Columnar body
23 .....
25 ... Bearing part
27 ...... Pocket
28... The surface from the base end of the columnar body to the pocket
29 …… Surface from the pocket to the approach
30 ... Dice female type
50 ... Reinforcing ribs
100 ... pipe
101 ··· Partition wall
102 .. Hollow part
200 ... pipe
201 ··· Partition wall
202. .. hollow part
250 ... Heat exchange tube
251 ... Outer fin

Claims

A die female mold that forms the outer periphery of the tube, and a mandrel combined with the die female mold,
The mandrel has a main body and a plurality of columnar bodies that protrude from the main body in a comb-like shape and are arranged at intervals in the width direction, and the tip outer periphery of the columnar body is arranged in the width direction of the tube. It is a bearing part that forms the inner peripheral surface of a plurality of hollow parts provided,
On the rear side in the extrusion direction from the bearing part, both surfaces in the thickness direction of the columnar body are recessed inward in the thickness direction from the position of the bearing part, so that at least one side in the thickness direction of the columnar body, A pocket that is a space for filling the molding material is formed,
The surface in the thickness direction of the columnar body following the pocket portion from the base end portion of the columnar body is formed as an inclined surface or curved surface for promoting introduction into the pocket portion of the molding material, and the inclined surface or curved surface and pocket There is no step between the portion and the surface in the thickness direction of the columnar body following the bearing portion from the pocket portion is formed as an inwardly convex curved surface having no surface orthogonal to the extrusion direction. A die for extruding a fine multi-hole tube, characterized in that both surfaces in the width direction of the front end are formed on a flat surface having no step.

2. The die for extruding a fine multi-hole tube according to claim 1, wherein a reinforcing rib protrudes from the front end surface of the columnar body.

The die for extruding a fine multi-hole tube according to claim 1 or 2, wherein a width of the columnar body in the bearing portion is 2.0 mm or less, and an interval between the bearing portions of adjacent columnar bodies is 0.6 mm or less.

The die for extruding a micro multi-hole tube according to any one of claims 1 to 3, wherein a groove is formed on at least one surface of the bearing in the thickness direction of the columnar body.

A mandrel combined with a female die that forms the outer periphery of a tube, and having a main body and a plurality of columnar bodies protruding from the main body in a comb-like shape and arranged at intervals in the width direction, The outer peripheral portion at the tip of the columnar body serves as a bearing portion that forms the inner peripheral surfaces of a plurality of hollow portions arranged in the width direction of the tube, and the thickness of the columnar body on the rear side in the extrusion direction from the bearing portion. Both sides of the direction are recessed inward in the thickness direction from the position of the bearing portion, so that a pocket portion which is a space for filling a molding material is formed on at least one side in the thickness direction of the columnar body, and The surface in the thickness direction of the columnar body following the pocket portion from the base end portion of the columnar body is formed as an inclined surface or curved surface for promoting introduction into the pocket portion of the molding material, and the inclined surface or curved surface and pocket portion not step between the The thickness direction of the surface of the columnar body from the pocket portion following the bearing portion is formed in a curved surface of the non-existent inwardly convex surface perpendicular to the extrusion direction, the width direction of both sides of the front end portion of the columnar body step A mandrel used for a die for extruding a fine multi-hole tube, characterized in that the mandrel is formed on a flat surface having no surface.

The mandrel according to claim 5, wherein a reinforcing rib protrudes from the tip surface of the columnar body.

The mandrel according to claim 5 or 6, wherein the width of the columnar body in the bearing portion is 2.0 mm or less, and the interval between the bearing portions of adjacent columnar bodies is 0.6 mm or less.

The die for extruding a fine multi-hole tube according to any one of claims 5 to 7, wherein a groove is formed on at least one surface in the thickness direction of the columnar body in the bearing portion.

A die for extrusion comprising a female die for forming the outer periphery of a tube and a mandrel combined with the female die,
The mandrel has a main body and a plurality of columnar bodies that protrude from the main body in a comb-like shape and are arranged at intervals in the width direction, and the tip outer periphery of the columnar body is arranged in the width direction of the tube. It is a bearing part that forms the inner peripheral surface of a plurality of hollow parts provided,
On the rear side in the extrusion direction from the bearing part, both surfaces in the thickness direction of the columnar body are recessed inward in the thickness direction from the position of the bearing part, so that at least one side in the thickness direction of the columnar body, A pocket that is a space for filling the molding material is formed,
The surface in the thickness direction of the columnar body following the pocket portion from the base end portion of the columnar body is formed as an inclined surface or curved surface for promoting introduction into the pocket portion of the molding material, and the inclined surface or curved surface and pocket There is no step between the portion and the surface in the thickness direction of the columnar body following the bearing portion from the pocket portion is formed as an inwardly convex curved surface having no surface orthogonal to the extrusion direction. Extrusion dies formed on a flat surface with no steps on both sides in the width direction of the tip,
A multi-hole tube having a large number of fine hollow portions that are manufactured by using a partition wall and partitioned by a partition wall in the width direction.

The fine multi-hole tube according to claim 9, wherein a reinforcing rib protrudes from a tip end surface of the columnar body of the extrusion die.

The fine multi-hole tube according to claim 9 or 10, wherein the hollow portion has a width of 2.0 mm or less and the partition wall has a thickness of 0.6 mm or less.

The protrusion part is formed between the adjacent partition walls in a hollow part by forming the groove part in at least one surface of the thickness direction of the columnar body in the bearing part of the die for extrusion. The fine multi-hole tube described in 1.

A die female die that forms the outer periphery of the tube and a mandrel combined with the die female die, the mandrel projecting in a comb-like shape from the main body and arranged in a row in the width direction. A plurality of columnar bodies, and an outer peripheral portion of the tip of the columnar body serves as a bearing portion that forms an inner peripheral surface of a plurality of hollow portions arranged in the width direction of the tube, and is extruded more than the bearing portion. On the rear side in the direction, both sides in the thickness direction of the columnar body are recessed inward in the thickness direction from the position of the bearing portion, so that at least one surface side in the thickness direction of the columnar body has a space for filling a molding material. A pocket portion is formed, and the surface in the thickness direction of the columnar body following the pocket portion from the base end portion of the columnar body is formed as an inclined surface or a curved surface for promoting introduction of the molding material into the pocket portion. And there is no such inclined surface No difference in level between the curved surface and the pocket portion, with the thickness direction of the surface of the columnar body following said bearing portion from the pocket portion is formed on the curved surface of the non-existent inwardly convex surface perpendicular to the extrusion direction, Both sides in the width direction of the tip of the columnar body use an extrusion die formed on a flat surface without a step,
A method for producing a heat exchange tube, comprising extruding a molding material from the extrusion die.

The method for producing a heat exchange tube according to claim 13, wherein a reinforcing rib protrudes from the tip surface of the columnar body of the extrusion die.

The method for manufacturing a heat exchange tube according to claim 13 or 14, wherein the width of the columnar body in the bearing portion of the extrusion die is 2.0 mm or less, and the interval between the bearing portions of adjacent columnar bodies is 0.6 mm or less. .

The method for producing a heat exchange tube according to any one of claims 13 to 15, wherein a groove is formed on at least one surface of the columnar body in the thickness direction of the columnar body of the extrusion die.

A die for extrusion comprising a female die for forming the outer periphery of a tube and a mandrel combined with the female die,
The mandrel has a main body and a plurality of columnar bodies that protrude from the main body in a comb-like shape and are arranged at intervals in the width direction, and the tip outer periphery of the columnar body is arranged in the width direction of the tube. It is a bearing part that forms the inner peripheral surface of a plurality of hollow parts provided,
On the rear side in the extrusion direction from the bearing part, both surfaces in the thickness direction of the columnar body are recessed inward in the thickness direction from the position of the bearing part, so that at least one side in the thickness direction of the columnar body, A pocket that is a space for filling the molding material is formed,
The surface in the thickness direction of the columnar body following the pocket portion from the base end portion of the columnar body is formed as an inclined surface or curved surface for promoting introduction into the pocket portion of the molding material, and the inclined surface or curved surface and pocket There is no step between the portion and the surface in the thickness direction of the columnar body following the bearing portion from the pocket portion is formed as an inwardly convex curved surface having no surface orthogonal to the extrusion direction. Extrusion dies formed on a flat surface with no steps on both sides in the width direction of the tip,
A heat exchanger provided with a heat exchange tube having a large number of fine hollow portions that are manufactured by using and partitioned by a partition wall in the width direction.

The heat exchanger according to claim 17, wherein a reinforcing rib protrudes from a front end surface of the columnar body of the extrusion die.

The heat exchanger according to claim 17 or 18, wherein the width of the hollow portion of the heat exchange tube is 2.0 mm or less, and the thickness of the partition wall is 0.6 mm or less.

The heat exchanger according to any one of claims 17 to 19, wherein a fin portion protrudes between adjacent partition walls in the hollow portion of the heat exchange tube.

A die for extrusion comprising a female die for forming the outer periphery of a tube and a mandrel combined with the female die,
The mandrel has a main body and a plurality of columnar bodies that protrude from the main body in a comb-like shape and are arranged at intervals in the width direction, and the tip outer periphery of the columnar body is arranged in the width direction of the tube. It is a bearing part that forms the inner peripheral surface of a plurality of hollow parts provided,
On the rear side in the extrusion direction from the bearing part, both surfaces in the thickness direction of the columnar body are recessed inward in the thickness direction from the position of the bearing part, so that at least one side in the thickness direction of the columnar body, A pocket that is a space for filling the molding material is formed,
The surface in the thickness direction of the columnar body following the pocket portion from the base end portion of the columnar body is formed as an inclined surface or curved surface for promoting introduction into the pocket portion of the molding material, and the inclined surface or curved surface and pocket There is no step between the portion and the surface in the thickness direction of the columnar body following the bearing portion from the pocket portion is formed as an inwardly convex curved surface having no surface orthogonal to the extrusion direction. Extrusion dies formed on a flat surface with no steps on both sides in the width direction of the tip,
Of a heat exchanger that is manufactured by using a heat exchange tube having a large number of fine hollow portions partitioned by a partition wall in the width direction and brazing the heat exchange tubes and outer fins alternately. Method.

The method for manufacturing a heat exchanger according to claim 21, wherein a reinforcing rib is formed to protrude from a tip end surface of the columnar body of the extrusion die.

The method for manufacturing a heat exchanger according to claim 21 or 22, wherein the width of the hollow portion of the heat exchange tube is 2.0 mm or less, and the thickness of the partition wall is 0.6 mm or less.

The manufacturing method of the heat exchanger in any one of Claim 21 thru | or 23 by which the fin part protrudes between the adjacent partition walls in the hollow part of a heat exchange tube.