JP3795250B2 - Multi-plate oil cooler cooling element - Google Patents

Multi-plate oil cooler cooling element Download PDF

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JP3795250B2
JP3795250B2 JP9380099A JP9380099A JP3795250B2 JP 3795250 B2 JP3795250 B2 JP 3795250B2 JP 9380099 A JP9380099 A JP 9380099A JP 9380099 A JP9380099 A JP 9380099A JP 3795250 B2 JP3795250 B2 JP 3795250B2
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plate
upward
downward
upper plate
lower plate
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JP2000283686A (en
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勝也 山田
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株式会社マーレ フィルターシステムズ
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D1/00—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators
    • F28D1/02—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid
    • F28D1/03—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with plate-like or laminated conduits
    • F28D1/0308—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with plate-like or laminated conduits the conduits being formed by paired plates touching each other
    • F28D1/0325—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with plate-like or laminated conduits the conduits being formed by paired plates touching each other the plates having lateral openings therein for circulation of the heat-exchange medium from one conduit to another
    • F28D1/0333—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with plate-like or laminated conduits the conduits being formed by paired plates touching each other the plates having lateral openings therein for circulation of the heat-exchange medium from one conduit to another the plates having integrated connecting members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F3/00—Plate-like or laminated elements; Assemblies of plate-like or laminated elements
    • F28F3/02—Elements or assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with recesses, with corrugations
    • F28F3/025—Elements or assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with recesses, with corrugations the means being corrugated, plate-like elements
    • F28F3/027—Elements or assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with recesses, with corrugations the means being corrugated, plate-like elements with openings, e.g. louvered corrugated fins; Assemblies of corrugated strips
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F2225/00—Reinforcing means
    • F28F2225/04—Reinforcing means for conduits

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Lubrication Of Internal Combustion Engines (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)

Abstract

PROBLEM TO BE SOLVED: To maintain the rigidity of the end of an element, and also facilitate the assembly, without using surplus reinforcing parts, as the cooling element of a multiboard oil cooler. SOLUTION: In the sectional view of the end of a slender cooling element where single tube bodies each of which is made by placing a downward pan-shaped upper plate 11 and an upward pan-shaped lower plate 12 opposite each other, with a porous corrugated fin plate 13 interposed between, are put on another in plural stages, the downward tubular projection 11d provided at the upper plate 11 is inserted into the through hole 12c of the lower plate and the tip is set in and joined with the back hole of the tubular projection 11d provided at the upper plate in its lower stage on one side, and the upward tubular projection 12d provided at the lower plate 12 is inserted into the through hole 11c of the upper plate and the tip is set in and joined with the back hole of the tubular projection 12d provided at the lower plate in the upper stage on the other, on both sides of the pipe part constituting the inlet and outlet for oil consisting of the upward pipe part 11b of the upper plate 11 and the downward pipe part 12b of the lower plate 12, and pillar members by the tubular projections are made on both sides of the oil pipe, thus the rigidity of the end of the element is maintained, without using other parts.

Description

【０００１】
【発明の属する技術分野】
この発明は部品点数を少なくしながら剛性を維持し、しかも組立て易くした多板式のオイルクーラの冷却エレメントに関する。
【０００２】
【従来の技術】
バス，トラック及び産業車両等に搭載されるディーゼルエンジンでは、図４（ａ）のようにエンジンブロックＥｂの側部にオイルクーラＯｃを配設し、その冷却エレメントＣｅを同図（ｂ）のように蓋フランジＦによりエンジンブロックＥｂの側壁に取付けてウォータジャケットＷ中に臨ませ、ラジエータＲからポンプＰにより循環させられる冷却水を実線矢印のように取入れる一方、オイルパンＯｐからエンジンの摺動部分や軸受部分に送られるオイルを点線矢印のように対向させて取入れて熱交換させ、オイルの温度を所定に保つようにしている。
【０００３】
図５は従来の多板式冷却エレメントの一例の一部分即ち単一段（最下段）のオイル通路を形成するチューブ体を分離して示すものであり、厚さが０．３〜０．４ｍｍ程度のステンレス鋼板からなる楕円形状の下向き浅皿状の上プレート１と、同様の上向き皿状の下プレート２と、両者の間に配置される厚さが０．３ｍｍ程度の鋼板からなる多孔波状のフィンプレート３及びこのフィンプレート３の両端に対向配置されるフィンプレートの高さにほぼ等しい厚さ（３〜４ｍｍ程度）の鋼板からなる曲玉状の補強を兼ねたオイルガイド板４、これと同程度の厚さの鋼板からなるスペーサリング５などを備えている。
【０００４】
上プレート１は周りが下向き縁壁１ａで囲まれ、最上段になるものを除いて長手方向の両端部にオイルの入口（図では右側）又は出口（同左側）をなす上向きパイプ部１ｂが設けられると共に各パイプ部１ｂの周りには溶融ろう材を通すための複数の細孔１ｄが設けられ、両端パイプ部１ｂの中間板面には間隔の維持と熱交換面積の増大を目的としてプレス加工された多数の突子１ｃが上向きに形成されており、一方、下プレート２は周りが上向き縁壁２ａで囲まれ、長手方向の両端部にはオイルの入口又は出口になる下向きパイプ部２ｂが設けられると共にそれらの周りには溶融ろう材を通すための複数の細孔２ｄが設けられ、両端パイプ部２ｂの中間板面には間隔の維持と熱交換面積の増大を目的としてプレス加工された多数の突子２ｃが下向きに形成され、また、フィンプレート３は両端中央部に半円状の切欠部を有し、それらの左又は右側に配置される曲玉状のオイルガイド板４の弧状内周面とで円形をなして、上，下のプレートの上向き又は下向きパイプ１ｂ，２ｂに揃うようになされている。
【０００５】
そして、上記フィンプレート３とオイルガイド板４を中間に介在させて上プレート１と下プレート２を突き合せたものを単一のチューブ体となし、これを図６のように複数段に積層して冷却エレメントＣｅを構成するわけであるが、その場合、図５における下プレート２の中に先ずほぼ同じ大きさで同じ形状の銅ろう箔８をおき、その上にフィンプレート３と曲玉状のオイルガイド板４を並べておき、それらの上に再び同じ大きさの銅ろう箔８をのせ、その上から上プレート１をその下向きの縁壁１ａが下プレート２の上向きの縁壁２ａの内側に嵌合する状態に突き合せる。
【０００６】
また、同様に形成した他段のものを積層するに当たっては、図６のように下段のものの上プレート１の両端の上向きパイプ部１ｂの外側にスペーサリング５をそれぞれ嵌め合せると共にそれらの上向きパイプ部１ｂの内側に上段のものの下段プレート２両端の下向きパイプ２ｂを嵌め込むというようにして複数段積層し、最上段のものの上プレート１の両端部上には所定大きさの銅ろう箔（図示せず）を介して鋼板からなる補強板６を配置し、また最下段のものの下プレート２両端の下向きパイプ部２ｂに、鋼板からなる菱形状のフランジ７の中央のボス孔７ａを環状の銅ろう箔８（図５）を介在させて嵌め合せ、かつフランジ７両側の通孔７ｂに小径環状の銅ろう材を介在させて一対のねじ杆９を挿通しておき、このようにチューブ体を複数段に積層したものが治具に収められ、上に重しがのせられて、加熱炉に入れられ、各部材が液密にろう付けされる。
【０００７】
上記のようにして組立てられた冷却エレメントＣｅは、図６のように最下段の下プレート２に固着されたフランジ７のねじ杆９を介し、オイルの入口パイプＦａと出口パイプＦｂを備えた蓋フランジＦに取付けられ、かつ蓋フランジＦがエンジンブロックＥｂの側壁に取付けられてウォータジャケットＷ内に配置され、入口パイプＦａから冷却エレメントＣｅの各段のチューブ体中に取入られたオイルをウォータジャケットＷ内を流れる冷却水により冷却するように使用される。
【０００８】
【発明が解決しようとする課題】
一般に多板式の冷却エレメントのチューブ体内部には、高いオイル圧（２〜８ｋｇ／ｃｍ２）が作用するが、上下プレート間はフィンプレート及びオイルガイド板を介してろう付け接合されていて、熱伝達の向上とともにチューブ体の間隙の拡大及び外周ろう付接合部の剥離を防止している。両端部に何もないとすると、その部分のふくれや接合部の剥離現象を起こすところから、上記従来の冷却エレメントでは各チューブ体中の両端部に前記曲玉状のオイルガイド板４を配設したり、各パイプ部の周りにスペーサリング５を設けたりしていて、部品点数が多く、重量の増大とコスト高を招き、オイルガイド板やスペーサリングの専有空間だけ熱交換面積が小さくなっている。
【０００９】
そこで、この発明はこれまでのような曲玉状のオイルガイド板やスペーサリングを用いることなく、部品点数を少なくしながら上プレートと下プレートからなるチューブ体両端部の剛性を維持すると共に冷却エレメントの重量の軽減と熱交換面積の増加を図り、しかもエレメントの組立をやり易くすることを課題とする。
【００１０】
【課題を解決するための手段】
上記課題のもとにこの発明は、車両などに用いられる多板式オイルクーラの冷却エレメントとして、芯材の両面にろう材を配した上プレートと下プレート及びその間に配置される鋼板からなる多孔波状のフィンプレートからなり、上プレートの下向き皿状体部の両端部にオイルの入口または出口をなす上向きパイプ部をその外側半円部が皿状体部から張り出す状態に設け、それら張出し半円部の前後の両側に所定直径の通孔と、この通孔に挿通可能で下段の上プレートを突き抜ける高さの先細りな下向き筒状突起をそれぞれ上プレートの対角線上にあるように設け、また下プレートの上向き皿状体部の両端部にオイルの入口または出口をなす下向きパイプ部をその外側半円部が皿状体部から張出す状態に設け、それら張出し半円部の前後の両側に所定直径の通孔と、この通孔に挿通可能で上段の下プレートを突き抜ける高さの先細りな上向き筒状突起を上プレート両端部の通孔と筒状突起とは前後の位置を異ならせて設け、上記フィンプレートを介在させ、かつ上プレートの下向き筒状突起を下プレートの通孔に挿通すると共に下プレートの上向き筒状突起を上プレートの通孔に挿通して単一のチューブ体となし、上段チューブ体の下向き筒状突起の先端を下段チューブ体の下向き筒状突起に嵌め込み接合する一方、下段チューブ体の上向き筒状突起の先端を上段の上向き筒状突起に嵌め込み接合してチューブ体を複数段に積層し、最上段の上プレート両端のパイプ部上には補強板を接合すると共に最下段の下プレート両端のパイプ部下にはフランジを接合し、積層チューブ体の両端パイプ部の両側に下向き筒状突起及び上向き筒状突起による柱部材を形成したことを特徴とするものである。
【００１１】
【発明の実施の形態】
図１はこの発明に係る冷却エレメントの単一段（最下段）のチューブ体を分離して示し、図２はそのチューブ体を複数段積層した状態の断面を示し、また図３は図２のＸ−Ｘ線に沿った一端部の断面を示すものであり、図１において１１は楕円形状をなす下向き皿状の上プレートで０．３〜０．４ｍｍ程度の厚さのステンレス鋼板の両面に厚さが２０μ程度の無酸素銅の薄板ろう材を圧延圧接法などによって接合したクラッド材からなり、周囲に上向きの縁壁１１ｆを有し、長さの大部分（９０％程度）は長方形状の下向き皿状体部１１ａをなし、その壁板には間隔の維持と熱交換面積の増大を目的とした多数の突子１１ｅが上向きに設けられ、この皿状体部１１ａの両端部には、オイルの入口（図で右）又は出口（同左）となる円形の上向きパイプ部１１ｂが、その外側半円部が皿状体部より右又は左に張り出す状態に設けられ、それらの上向きパイプ部１１ｂの半円状の張り出し部分の前後方向の両側の位置には、所定直径の通孔１１ｃと、この通孔１１ｃに挿通可能で、下段のチューブ体の上プレートを突き抜ける程度の高さの先細りになった下向きの筒状突起１１ｄがそれぞれ設けられ、両端部における通孔１１ｃと筒状突起１１ｄはそれぞれ上プレート１１の対角線上に位置し、前後の関係が異なるようになされている。
【００１２】
１２は上向き皿状の下プレートで、上プレート１１と同じ大きさの楕円形状をなし、また、上プレート１１と同じく厚さが０．３〜０．４ｍｍ程度のステンレス鋼板の両面に無酸素銅の薄板ろう材を接合した同じ厚さのクラッド材からなり、周囲に下向きの縁壁１２ｆ（図２参照）を有し、長さの大部分（９０％程度）は長方形状の上向き皿状体部１２ａをなし、その壁板には間隔の維持と熱交換面積の増大を目的とした多数の突子１２ｅが設けられ、皿状体部１２ａの両端部にはオイルの入口（図で右）又は出口（同左）となる円形の下向きパイプ部１２ｂが、その外側半円部が皿状体部より右又は左に張り出す状態に設けられ、それら下向きパイプ部１２ｂの半円状の張出し部分の前後方向の両側の位置には、上プレートの通孔１１ｃと同じ直径の通孔１２ｃと、この通孔１２ｃの挿通可能で、上段のチューブ体の下プレートを突き抜ける程度の高さの先細りになった上向きの筒状突起１２ｄ（高さは上プレートの筒状突起１１ｄと同じ）が、上プレート１１の通孔１１ｃと筒状突起１１ｄとは前後の関係を逆にしてそれぞれ設けられている。しかし、両端部における通孔１２ｃと筒状突起１２ｄはそれぞれ下プレート１２の対角線上に位置し、かつ前後の関係が異なることは上プレート１１と同じである。
【００１３】
換言すれば、上プレート１１と下プレート１２は互いに裏返した関係にあり、そして、最上段のチューブ体の下プレート１２に設けられる上向き筒状突起１２ｄの高さは図３に示すように上プレート１１の皿状体部１１ａの上面に揃うようになされ、また最下段の上プレート１１に設けられる下向き筒状突起１１ｄの高さは下プレート１２の皿状体部１２ａの下面に揃うようになされている。
【００１４】
１３は長方形状をなした多孔波状のフィンプレートで、厚さが０．３ｍｍ程度の鋼板からなり、上プレート１１の下向き皿状体部１１ａと下プレート１２の上向き皿状体部１２ａの間において、両皿状体部の内面に当接する高さとその内側幅にほぼ等しい幅と両端のパイプ部１１ｂ，１２ｂの一部をおおう程度の長さに形成されている。
【００１５】
また、図１において１７は厚手（６〜８ｍｍ程度）の鋼板からなる菱形状のフランジで、その長手軸線がプレートの長手軸線に沿う状態に両端部に配置され、中央に最下段の下プレート１２の下向きパイプ部１２ｂを嵌合させるボス孔１７ａを有すると共に長手軸線の両側にはねじ杆１８を挿通してその頭部を固定（ろう付け）する通孔１７ｂを備えている。
【００１６】
かくて、図１における上プレート１１の下向き皿状体部１１ａと下プレート１２の上向き皿状体部１２ａとの間にフィンプレート１３を配置して、上プレート１１と下プレート１２を突き合せて単一のチューブ体となし、これを図２，図３のように複数段積層するが、この場合、図３に示すように一側部では上プレート１１の端部に設けた下向きの筒状突起１１ｄを下プレート１２に設けた通孔１２ｃに挿通すると共にその先端を下段のチューブ体の上プレート１１に設けた筒状突起１１ｄに嵌め込む一方、他側では下プレート１２の端部に設けた上向きの筒状突起１２ｄを上プレート１１に設けた通孔１１ｃ挿通すると共にその先端を上段のチューブ体の下プレート１２に設けた筒状突起１２ｄに嵌め込むというようにして、チューブ体を複数段に積層する。
【００１７】
その際、上プレート１１と下プレート１２は通孔１１ｃ，１２ｃと筒状突起１１ｄ，１２ｄとの挿通関係、上段のチューブ体と下段のチューブ体は筒状突起１１ｄまたは１２ｄ同士の嵌合関係によって位置決めされながら積層されることになる。
【００１８】
そして、最上段のチューブ体の両端の上向きパイプ部１１ｂの上に孔ふさぎを兼ねた鋼板からなる補強板１６を配設する一方、最下段のチューブ体の下プレート１２両端の下向きパイプ部１２ｂにはフランジ１７の中央ボス孔１７ａを嵌め合せると共に両側の通孔１７ｂには小径環状の銅ろう材を介在させながらねじ杆１８を挿通し、このようにして積層チューブ体をまとめたものが治具に収められ、上に重しがのせられて加熱炉に入れられ、各部材が液密にろう付けされて図２，図３のように冷却エレメントＣｅが形成される。
【００１９】
その際には、図２，図３にみられるように上段チューブ体の下プレートの両端部における下向きパイプ部１２ｂが下段チューブ体の上プレート１１の上向きパイプ部に接合されるが、それと同時に各パイプ部の両側において、上段チューブ体の上プレート１１の下向き筒状突起１１ｄが下段のものの下向き筒状突起１１ｄに接合され、かつ下段チューブ体の下プレート１２の上向き筒状突起１２ｄが上段のものの上向き筒状突起１２ｄに接合されることになり、各パイプ部の両側には筒状突起１１ｄ，１２ｄが上下に連なった柱部材が形成される。
【００２０】
そして、上記のように組立てられた冷却エレメントＣｅは、最下段の下プレート１２に固着されたフランジ１７のねじ杆１８を介し、オイルの入口パイプＦａと出口パイプＦｂを備えた蓋フランジＦに取付けられ（図２ではフランジのねじ杆１８にナットをねじ込み易いようにパイプＦａ，Ｆｂは紙面に垂直方向に曲げられている）、また、その蓋フランジＦがエンジンブロックＥｂの側壁に取付けられてウォータジャケットＷ内に配置され、入口パイプＦａからオイルが、冷却エレメントＣｅの入口側のパイプを通じ各段のチューブ体内に出口側に向って取入れられ、その外側において対向する状態にウォータジャケットＷ内を流れる冷却水と熱交換するように使用される。そのとき、冷却エレメントＣｅに冷却水の動圧やオイルの脈動圧、エンジンの振動などが作用したにしても、両端部にはパイプ部の前後の両側において上下に連なる下向き筒状突起１１ｄまたは上向き筒状突起１２ｄからなる柱部材が形成されているので、それらの柱部材によってエレメント両端部の剛性が充分に維持され、妄りに揺動したり、座屈したり、破損したりすることがない。
【００２１】
なお、図示の例では上，下のプレート１１，１２を楕円形状のものを示したが、これは長方形状のものとしてもよい。また、上下プレートの材料として、芯材の両面に銅ろう材を接合したクラッド材を用いたが、電気銅をメッキ処理したものであっても、さらには各部材間に銅ろう箔を配するようにしてもよい。さらに、図示の例では、ステンレス鋼板製の冷却エレメントについて例示したが、モネル合金製やアルミニム製等であってもよく、材料には限定されない。
【００２２】
【発明の効果】
この発明は車両などに用いられる多板式オイルクーラの冷却エレメントとして、上述のように構成されているので、これまでのような曲玉状のオイルガイド板やスペーサリングを必要としないで、冷却エレメントの両端部における剛性を充分に維持し、かつ剥離を防止することができ、部品点数が少なく、重量を軽減することができ、しかも、上プレートと下プレートとは筒状突起と通孔との挿通関係及び上段のチューブ体と下段のチューブ体とは下向き又は上向きの筒状突起同士の嵌合関係によって位置決めしながら組立ることができ、組立て作業が甚だ容易であり、治具での位置決めは必要ないので治具を簡素化でき、また上プレートと下プレートは裏返した関係にあるので量産に適している。
【図面の簡単な説明】
【図１】この発明に係る冷却エレメントの単一段のチューブ体の分離斜視図。
【図２】冷却エレメント全体の断面図。
【図３】図２のＸ−Ｘ線に沿った端部の断面図。
【図４】（ａ）はオイルクーラの使用状態を示す斜視図。
（ｂ）は冷却エレメントの配置状態を示す説明図。
【図５】従来の冷却エレメントの単一段のチューブ体の分離斜視図。
【図６】従来の冷却エレメントの断面図。
【符号の説明】
１１ 上プレート
１１ａ 下向き皿状体部
１１ｂ 上向きパイプ部
１１ｃ 通孔
１１ｄ 下向き筒状突起
１２ 下プレート
１２ａ 上向き皿状体部
１２ｂ 下向きパイプ部
１２ｃ 通孔
１２ｄ 上向き筒状突起
１３ フィンプレート
１６ 補強板
１７ フランジ
Ｃｅ 冷却エレメント[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cooling element of a multi-plate type oil cooler that maintains rigidity while reducing the number of parts and is easy to assemble.
[0002]
[Prior art]
In a diesel engine mounted on buses, trucks, industrial vehicles, etc., an oil cooler Oc is disposed on the side of the engine block Eb as shown in FIG. 4A, and its cooling element Ce is shown in FIG. It is attached to the side wall of the engine block Eb by the cover flange F and faces the water jacket W, and the coolant circulated by the pump P from the radiator R is taken in as indicated by the solid line arrow, while the engine slides from the oil pan Op. The oil sent to the part and the bearing part is taken in oppositely as indicated by the dotted arrows and heat exchange is performed to keep the oil temperature at a predetermined level.
[0003]
FIG. 5 shows a part of an example of a conventional multi-plate type cooling element, that is, a tube body forming a single-stage (bottom-stage) oil passage separately, and a stainless steel having a thickness of about 0.3 to 0.4 mm. An elliptical downward plate-shaped upper plate 1 made of a steel plate, a similar upward plate-shaped lower plate 2, and a perforated wave-shaped fin plate made of a steel plate having a thickness of about 0.3 mm disposed therebetween 3 and an oil guide plate 4 also serving as a curved ball-shaped reinforcement made of a steel plate having a thickness (about 3 to 4 mm) substantially equal to the height of the fin plate disposed opposite to both ends of the fin plate 3, and the same degree as this The spacer ring 5 made of a steel plate having a thickness of 5 mm is provided.
[0004]
The upper plate 1 is surrounded by a downward-facing edge wall 1a. Except for the uppermost plate, the upper plate 1 is provided with an upward pipe portion 1b that forms an oil inlet (right side in the figure) or an outlet (left side in the figure) at both ends in the longitudinal direction. In addition, a plurality of pores 1d are provided around each pipe portion 1b to allow the molten brazing material to pass therethrough, and the intermediate plate surface of both end pipe portions 1b is pressed for the purpose of maintaining a gap and increasing the heat exchange area. On the other hand, the lower plate 2 is surrounded by an upward edge wall 2a, and at both ends in the longitudinal direction, downward pipe portions 2b serving as oil inlets or outlets are formed. A plurality of pores 2d are provided around them to allow the molten brazing material to pass through, and the intermediate plate surface of both end pipe portions 2b is pressed for the purpose of maintaining the distance and increasing the heat exchange area. Many protrusions 2c The fin plate 3 has a semicircular cutout at the center of both ends and is circular with the arcuate inner peripheral surface of the curved oil guide plate 4 arranged on the left or right side thereof. Thus, the upper and lower plates are aligned with the upward or downward pipes 1b, 2b.
[0005]
A single tube body is formed by abutting the upper plate 1 and the lower plate 2 with the fin plate 3 and the oil guide plate 4 interposed therebetween, and this is laminated in a plurality of stages as shown in FIG. In this case, first, a copper brazing foil 8 having substantially the same size and shape is first placed in the lower plate 2 in FIG. 5, and the fin plate 3 and the curved ball shape are placed thereon. The oil guide plates 4 are placed side by side, and a copper brazing foil 8 of the same size is again placed on them, and the upper plate 1 is placed on the inner side of the upper edge wall 2a of the lower plate 2 with its downward edge wall 1a facing downward. To fit into the state.
[0006]
Further, when stacking the other stages formed in the same manner, as shown in FIG. 6, the spacer rings 5 are fitted on the outer sides of the upward pipe portions 1b at both ends of the upper plate 1 of the lower stage, and the upward pipe portions thereof are respectively fitted. A plurality of layers are stacked such that the downward pipes 2b at both ends of the upper plate 1b are fitted inside the upper plate 1b, and a copper brazing foil of a predetermined size (not shown) is placed on both ends of the upper plate 1 of the uppermost one. The reinforcing plate 6 made of a steel plate is disposed via the lower boss plate 2b at both ends of the lower plate 2 and the center boss hole 7a of the diamond-shaped flange 7 made of steel plate is formed into an annular copper braze. The foil 8 (FIG. 5) is fitted and fitted, and a pair of screw rods 9 are inserted in the through holes 7b on both sides of the flange 7 with a small diameter annular copper brazing material interposed therebetween. A laminate of the stage are contained in a jig, by weigh is placed on top, placed in the heating furnace, each member is brazed in a liquid-tight manner.
[0007]
The cooling element Ce assembled as described above is a lid provided with an oil inlet pipe Fa and an outlet pipe Fb via a screw rod 9 of a flange 7 fixed to the lower plate 2 at the lowest stage as shown in FIG. Oil that is attached to the flange F, and the lid flange F is attached to the side wall of the engine block Eb and is arranged in the water jacket W, and is taken into the tube body of each stage of the cooling element Ce from the inlet pipe Fa. It is used to be cooled by cooling water flowing in the jacket W.
[0008]
[Problems to be solved by the invention]
In general, a high oil pressure ( 2 to 8 kg / cm 2 ) acts inside the tube body of a multi-plate type cooling element, but the upper and lower plates are brazed and joined via fin plates and oil guide plates. As well as improving transmission, the gap between the tube bodies is enlarged and the outer brazed joint is prevented from peeling off. If there is nothing at both ends, the above-described conventional cooling element has the curved oil guide plate 4 disposed at both ends in each tube body, since this causes the phenomenon of blistering and separation of the joint. Or a spacer ring 5 around each pipe part, which increases the number of parts, increases the weight and costs, and reduces the heat exchange area only in the space dedicated to the oil guide plate and spacer ring. Yes.
[0009]
Therefore, the present invention maintains the rigidity of both ends of the tube body composed of the upper plate and the lower plate while reducing the number of parts without using a curved oil guide plate or spacer ring as in the past, and a cooling element. It is an object of the present invention to reduce the weight and increase the heat exchange area, and to make it easy to assemble the element.
[0010]
[Means for Solving the Problems]
Based on the above-mentioned problems, the present invention provides a multi-plate oil cooler used in a vehicle or the like as a cooling element, comprising an upper plate having a brazing material on both sides of a core material, a lower plate, and a porous corrugated plate comprising a steel plate disposed therebetween. The upper pipe has an upward pipe part that forms the inlet or outlet of oil at both ends of the downward plate-like body part of the upper plate, with its outer semicircle projecting from the dish-like body part. A through-hole with a predetermined diameter is provided on both the front and back sides of the section, and tapered downward cylindrical projections that can be inserted into the through-hole and penetrate the lower upper plate so as to lie on the diagonal of the upper plate. A downward pipe part that forms the inlet or outlet of oil is provided at both ends of the upward dish-shaped body part of the plate so that the outer semicircular part projects from the dish-shaped body part. A through-hole with a predetermined diameter and a tapered upward cylindrical protrusion that can be inserted through this through-hole and penetrate the lower plate of the upper stage are different from each other in the front and rear positions of the through-hole and the cylindrical protrusion at both ends of the upper plate. A single tube body with the fin plate interposed therebetween and the downward cylindrical protrusion of the upper plate inserted into the through hole of the lower plate and the upward cylindrical protrusion of the lower plate inserted into the through hole of the upper plate The tip of the downward cylindrical projection of the upper tube body is fitted and joined to the downward cylindrical projection of the lower tube body, while the tip of the upward cylindrical projection of the lower tube body is fitted and joined to the upward cylindrical projection of the upper stage. The tube bodies are stacked in multiple stages, and reinforcing plates are joined to the pipes at both ends of the uppermost upper plate, and flanges are joined to the pipes at both ends of the lowermost plate at the lowermost stage. It is characterized in that on both sides of the pipe section to form a pillar member according to a downward tubular projecting and upward tubular projecting.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
1 shows a single-stage (bottom-stage) tube body of the cooling element according to the present invention separately, FIG. 2 shows a cross-section of the tube bodies stacked in a plurality of stages, and FIG. 3 shows an X of FIG. FIG. 1 shows a cross section of one end along the X-ray. In FIG. 1, reference numeral 11 denotes an elliptical downward plate-like upper plate having a thickness on both sides of a stainless steel plate having a thickness of about 0.3 to 0.4 mm. It is made of a clad material obtained by joining an oxygen-free copper brazing material having a thickness of about 20 μm by a rolling pressure welding method or the like, and has an upward edge wall 11f around it, and most of the length (about 90%) is rectangular. A downward dish-shaped body portion 11a is formed, and a large number of protrusions 11e are provided on the wall plate for the purpose of maintaining a space and increasing a heat exchange area. At both ends of the dish-shaped body portion 11a, Upward circular shape for oil inlet (right in the figure) or outlet (left) The pipe part 11b is provided in a state where the outer semicircular part protrudes to the right or left from the dish-like body part, and the positions of both sides in the front-rear direction of the semicircular projecting part of the upward pipe part 11b are as follows: A through-hole 11c having a predetermined diameter and a downward cylindrical projection 11d that can be inserted into the through-hole 11c and have a taper height that penetrates the upper plate of the lower tube body are provided. The holes 11c and the cylindrical projections 11d are positioned on the diagonal line of the upper plate 11 and have different front-rear relationships.
[0012]
Reference numeral 12 denotes an upward dish-shaped lower plate which has an elliptical shape the same size as the upper plate 11 and is oxygen-free copper on both surfaces of a stainless steel plate having a thickness of about 0.3 to 0.4 mm, similar to the upper plate 11. Made of a clad material of the same thickness joined with a thin brazing filler metal, and has a downward edge wall 12f (see FIG. 2) around it, and most of the length (about 90%) is a rectangular upward dish The wall plate is provided with a number of protrusions 12e for the purpose of maintaining a gap and increasing the heat exchange area. Oil inlets (right in the figure) are provided at both ends of the dish-like body 12a. Or the circular downward pipe part 12b used as an exit (same as the left) is provided in a state where the outer semicircular part projects to the right or left from the dish-like body part, and the semicircular projecting part of the downward pipe part 12b At positions on both sides in the front-rear direction, through holes 11c in the upper plate A through-hole 12c having the same diameter, and an upward cylindrical protrusion 12d that can be inserted through the through-hole 12c and is tapered so as to penetrate the lower plate of the upper tube body (the height is the cylindrical shape of the upper plate) The same as the protrusion 11d), the through hole 11c of the upper plate 11 and the cylindrical protrusion 11d are provided with the front-rear relationship reversed. However, it is the same as the upper plate 11 that the through-holes 12c and the cylindrical protrusions 12d at both ends are located on the diagonal line of the lower plate 12, and the front-rear relationship is different.
[0013]
In other words, the upper plate 11 and the lower plate 12 are in an inverted relationship with each other, and the height of the upward cylindrical protrusion 12d provided on the lower plate 12 of the uppermost tube body is as shown in FIG. 11, and the height of the downward cylindrical projection 11 d provided on the lowermost upper plate 11 is aligned with the lower surface of the dish-like body portion 12 a of the lower plate 12. ing.
[0014]
Reference numeral 13 denotes a rectangular perforated corrugated fin plate made of a steel plate having a thickness of about 0.3 mm, between the downward plate-like body portion 11a of the upper plate 11 and the upward plate-like body portion 12a of the lower plate 12. The height of the two plate-like body portions that are in contact with the inner surface and the width substantially equal to the inner width of the two plate-like body portions are formed so as to cover a part of the pipe portions 11b and 12b at both ends.
[0015]
In FIG. 1, reference numeral 17 denotes a diamond-shaped flange made of a thick (about 6 to 8 mm) steel plate, the longitudinal axis of which is arranged at both end portions along the longitudinal axis of the plate, and the lowermost lower plate 12 at the center. A boss hole 17a for fitting the downward pipe portion 12b is provided, and a through hole 17b is provided on both sides of the longitudinal axis so that the screw rod 18 is inserted and the head portion is fixed (brazed).
[0016]
Thus, the fin plate 13 is disposed between the downward plate-like body portion 11a of the upper plate 11 and the upward plate-like body portion 12a of the lower plate 12 in FIG. 1, and the upper plate 11 and the lower plate 12 are brought into contact with each other. A single tube body is formed and laminated in a plurality of stages as shown in FIGS. 2 and 3. In this case, as shown in FIG. 3, a downward cylindrical shape provided at one end of the upper plate 11 is provided. The protrusion 11d is inserted into a through hole 12c provided in the lower plate 12, and the tip thereof is fitted into the cylindrical protrusion 11d provided in the upper plate 11 of the lower tube body, while being provided at the end of the lower plate 12 on the other side. The tubular body 12d is inserted into the through hole 11c provided in the upper plate 11 and the tip thereof is fitted into the cylindrical protrusion 12d provided in the lower plate 12 of the upper tube body. Stacked in several stages.
[0017]
At that time, the upper plate 11 and the lower plate 12 are inserted through the through holes 11c and 12c and the cylindrical protrusions 11d and 12d, and the upper tube body and the lower tube body are connected by the cylindrical protrusions 11d or 12d. It is laminated while being positioned.
[0018]
A reinforcing plate 16 made of a steel plate that also serves as a hole cap is disposed on the upward pipe portions 11b at both ends of the uppermost tube body, while the downward pipe portions 12b at both ends of the lower plate 12 at the lowermost tube body. The center boss hole 17a of the flange 17 is fitted together, and the screw rod 18 is inserted into the through hole 17b on both sides with a small-diameter annular copper brazing material interposed therebetween. 2 and placed in a heating furnace, each member is liquid-tightly brazed to form a cooling element Ce as shown in FIGS.
[0019]
In this case, as shown in FIGS. 2 and 3, the downward pipe portions 12b at both ends of the lower plate of the upper tube body are joined to the upward pipe portions of the upper plate 11 of the lower tube body. On both sides of the pipe portion, the downward cylindrical protrusion 11d of the upper plate 11 of the upper tube body is joined to the downward cylindrical protrusion 11d of the lower tube body, and the upward cylindrical protrusion 12d of the lower plate 12 of the lower tube body of the upper tube body is the upper one. The cylindrical members 12d are connected to the upward cylindrical protrusion 12d, and columnar members 11d and 12d are formed on both sides of each pipe portion.
[0020]
The cooling element Ce assembled as described above is attached to the lid flange F having the oil inlet pipe Fa and the outlet pipe Fb through the screw rod 18 of the flange 17 fixed to the lowermost lower plate 12. (In FIG. 2, the pipes Fa and Fb are bent in a direction perpendicular to the paper surface so that the nut can be easily screwed into the flange screw rod 18), and the lid flange F is attached to the side wall of the engine block Eb. It is arranged in the jacket W, and oil from the inlet pipe Fa is taken into the tube body of each stage through the pipe on the inlet side of the cooling element Ce toward the outlet side, and flows in the water jacket W in a state of being opposed to the outside. Used to exchange heat with cooling water. At that time, even if the dynamic pressure of the cooling water, the pulsation pressure of the oil, the vibration of the engine, etc. are applied to the cooling element Ce, the downward cylindrical projections 11d that are vertically connected on both the front and rear sides of the pipe portion or the upward Since the column members made of the cylindrical projections 12d are formed, the rigidity of the both end portions of the element is sufficiently maintained by these column members, so that they do not swing loosely, buckle or break.
[0021]
In the example shown in the figure, the upper and lower plates 11 and 12 are elliptical, but they may be rectangular. Moreover, although the clad material which joined the copper brazing material to both surfaces of the core material was used as the material of the upper and lower plates, even if the copper is plated with copper, a copper brazing foil is disposed between the members. You may do it. Furthermore, in the illustrated example, a cooling element made of a stainless steel plate is illustrated, but it may be made of a Monel alloy or aluminum, and is not limited to the material.
[0022]
【The invention's effect】
Since the present invention is configured as described above as a cooling element for a multi-plate oil cooler used in a vehicle or the like, it does not require a curved ball-shaped oil guide plate or a spacer ring as in the past. It is possible to maintain sufficient rigidity at both ends and prevent peeling, reduce the number of parts, reduce the weight, and the upper plate and the lower plate are formed between the cylindrical projection and the through hole. Insertion relationship and upper tube body and lower tube body can be assembled while positioning by fitting relationship between downward or upward cylindrical projections, assembly work is very easy, positioning with jig Since it is not necessary, the jig can be simplified, and the upper plate and the lower plate are reversed so that they are suitable for mass production.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of a single-stage tube body of a cooling element according to the present invention.
FIG. 2 is a cross-sectional view of the entire cooling element.
3 is a cross-sectional view of an end portion taken along line XX of FIG.
FIG. 4A is a perspective view showing a usage state of an oil cooler.
(B) is explanatory drawing which shows the arrangement | positioning state of a cooling element.
FIG. 5 is an exploded perspective view of a single-stage tube body of a conventional cooling element.
FIG. 6 is a cross-sectional view of a conventional cooling element.
[Explanation of symbols]
11 Upper plate 11a Down dish portion 11b Upward pipe portion 11c Through hole 11d Downward cylindrical projection 12 Lower plate 12a Upward dish portion 12b Downward pipe portion 12c Through hole 12d Upward tubular projection 13 Fin plate 16 Reinforcement plate 17 Flange Ce cooling element

Claims (2)

芯材の両面にろう材を配した上プレートと下プレート及びその間に配置される多孔波状のフィンプレートとからなり、上プレートの下向き皿状体部の両端部にオイルの入口または出口をなす上向きパイプ部をその外側半円部が皿状体部から張り出す状態に設け、それら張出し半円部の前後の両側に所定直径の通孔と、この通孔に挿通可能で下段の上プレートを突き抜ける高さの先細りな下向き筒状突起をそれぞれ上プレートの対角線上にあるように設け、また下プレートの上向き皿状体部の両端部にオイルの入口または出口をなす下向きパイプ部をその外側半円部が皿状体部から張出す状態に設け、それら張出し半円部の前後の両側に所定直径の通孔と、この通孔に挿通可能で上段の下プレートを突き抜ける高さの先細りな上向き筒状突起を上プレート両端部の通孔と筒状突起とは前後の位置を異ならせて設け、上記フィンプレートを介在させ、かつ上プレートの下向き筒状突起を下プレートの通孔に挿通すると共に下プレートの上向き筒状突起を上プレートの通孔に挿通して単一のチューブ体となし、上段チューブ体の下向き筒状突起の先端を下段チューブ体の下向き筒状突起に嵌め込み接合する一方、下段チューブ体の上向き筒状突起の先端を上段の上向き筒状突起に嵌め込み接合してチューブ体を複数段に積層し、最上段の上プレート両端のパイプ部上には補強板を接合すると共に最下段の下プレート両端のパイプ部下にはフランジを接合し、積層チューブ体の両端パイプ部の両側に下向き筒状突起及び上向き筒状突起による柱部材を形成したことを特徴とする多板式オイルクーラの冷却エレメント。An upper plate with a brazing material on both sides of the core, a lower plate, and a perforated corrugated fin plate placed between them. The pipe part is provided in a state where the outer semicircular part protrudes from the dish-like body part, a through hole having a predetermined diameter is formed on both sides of the projecting semicircular part, and the upper plate penetrates the lower stage. A tapered pipe projection with a tapered height is provided on each diagonal line of the upper plate, and a downward pipe part that forms an oil inlet or outlet at both ends of the upward plate-like body part of the lower plate has an outer semicircle. Provided in a state where the portion projects from the dish-shaped body portion, a through hole having a predetermined diameter on both sides before and after the projecting semicircular portion, and a tapered upward cylinder that can be inserted into the through hole and penetrates the lower plate of the upper stage Protrusion The through holes and the cylindrical protrusions at both ends of the plate are provided with different front and rear positions, the fin plate is interposed, and the downward cylindrical protrusions of the upper plate are inserted into the through holes of the lower plate and the upward direction of the lower plate The cylindrical protrusion is inserted into the through hole of the upper plate to form a single tube body. The tip of the downward cylindrical protrusion of the upper tube body is fitted into the downward cylindrical protrusion of the lower tube body and joined, while the lower tube body The tip of the upward cylindrical protrusion is fitted into the upper upward cylindrical protrusion and joined to stack the tube bodies in multiple stages. The reinforcing plate is joined to the pipes at both ends of the uppermost upper plate, and the lower lower plate A multi-plate oil characterized in that flanges are joined under the pipe portions at both ends, and pillar members are formed by downward cylindrical protrusions and upward cylindrical protrusions on both sides of the pipe portions at both ends of the laminated tube body. Cooling element of over La. 最上段の下プレートの上向き筒状突起及び最下段の上プレートの下向き筒状突起の一方または両方を所定の高さになしたことを特徴とする請求項１記載の多板式オイルクーラの冷却エレメント。2. A cooling element for a multi-plate oil cooler according to claim 1, wherein one or both of the upward cylindrical protrusion of the uppermost lower plate and the downward cylindrical protrusion of the lowermost upper plate have a predetermined height. .
JP9380099A 1999-03-31 1999-03-31 Multi-plate oil cooler cooling element Expired - Fee Related JP3795250B2 (en)

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US7343965B2 (en) * 2004-01-20 2008-03-18 Modine Manufacturing Company Brazed plate high pressure heat exchanger
JP4724602B2 (en) * 2006-05-17 2011-07-13 トーステ株式会社 Heat exchanger
KR100859153B1 (en) * 2007-09-27 2008-09-19 주식회사 원진 Laminated type oil cooler
US20090260789A1 (en) * 2008-04-21 2009-10-22 Dana Canada Corporation Heat exchanger with expanded metal turbulizer
CN201440047U (en) * 2009-07-23 2010-04-21 卡特彼勒公司 Heat exchanger device and machine using same
JP6122266B2 (en) * 2012-08-27 2017-04-26 株式会社マーレ フィルターシステムズ Heat exchanger
JP6329756B2 (en) * 2013-11-26 2018-05-23 株式会社マーレ フィルターシステムズ Oil cooler

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