JP2004053107A - Egr gas cooling device - Google Patents

Egr gas cooling device Download PDF

Info

Publication number
JP2004053107A
JP2004053107A JP2002210406A JP2002210406A JP2004053107A JP 2004053107 A JP2004053107 A JP 2004053107A JP 2002210406 A JP2002210406 A JP 2002210406A JP 2002210406 A JP2002210406 A JP 2002210406A JP 2004053107 A JP2004053107 A JP 2004053107A
Authority
JP
Japan
Prior art keywords
egr
pipe
egr gas
cooling device
engine
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP2002210406A
Other languages
Japanese (ja)
Other versions
JP4236879B2 (en
Inventor
Takahiko Naito
内藤　孝彦
Naoya Kubota
久保田　尚矢
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sankei Giken Kogyo Co Ltd
Original Assignee
Sankei Giken Kogyo Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sankei Giken Kogyo Co Ltd filed Critical Sankei Giken Kogyo Co Ltd
Priority to JP2002210406A priority Critical patent/JP4236879B2/en
Publication of JP2004053107A publication Critical patent/JP2004053107A/en
Application granted granted Critical
Publication of JP4236879B2 publication Critical patent/JP4236879B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies

Landscapes

  • Exhaust-Gas Circulating Devices (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide an EGR gas cooling device which recirculates part of exhaust gas ejected from an exhaust system of an engine of an automobile or the like as EGR gas to a intake system of the engine, of a simple structure and excellent in cooling effect. <P>SOLUTION: In an EGR cooling device provided with an outer tube 4 at an outer circumference of EGR piping 1 recirculating part of exhaust gas ejected from an exhaust system of an engine as EGR gas to an intake system of the engine and cooling water is circulated between the outer tube 4 and the EGR piping 1 to cool EGR gas passing through the EGR piping 1, a blockage A is provided in the EGR piping 1. Ring shape or spiral projection parts 1d, 1e are provided in for example the EGR piping 1, or a partition plate or a cylindrical body having a plurality of through holes is provided in the EGR piping as the blockage A. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、自動車等のエンジンの排気系から排出された排気ガスの一部をＥＧＲガスとしてエンジンの吸気系に再循環させるいわゆるＥＧＲガスの冷却装置に関する。
【０００２】
【従来の技術】
従来、上記のようなエンジンから排出される排気ガス中の窒素酸化物を低減させる等の目的で、エンジンの排気系から排出される排気ガスの一部をＥＧＲガスとしてエンジンの吸気系に再循環させるいわゆる排気ガス再循環（ＥＧＲ）装置を設けることは知られている。この場合、吸気系に再循環させるＥＧＲガスは、適度に冷却する必要があり、従来はＥＧＲ配管の途中に冷却手段を備えたＥＧＲガス冷却装置を設けるようにしている。
【０００３】
上記のようなＥＧＲガス冷却装置としては、例えば特開平１１−１９３９９２号や特開平１１−１９３９９３号公報に開示されているように、ＥＧＲガスを流通させるＥＧＲ配管を多数の管材で構成し、それらを覆う外管と上記ＥＧＲ配管との間に冷却水を流通させて上記ＥＧＲガスを冷却するものが知られているが、構造が複雑で製造コストが嵩み、また装置が大型化して車載重量が増大する等の問題がある。
【０００４】
そこで、例えば特開２００１−２０７９１９のようにＥＧＲ配管の外周に冷却水を流通させる筒状の外側水冷ジャケットを設けると共に、上記ＥＧＲ配管内に細い管状の内側水冷ジャケットを設けることが提案されている。しかしながら、ＥＧＲ配管内に細い管状の内側水冷ジャケットを設けるのは、煩雑かつ面倒で製作コストが嵩む等の不具合がある。
【０００５】
また例えば特開２０００−２６５９０８のようにＥＧＲ配管を単管とし、そのＥＧＲ配管の外周に冷却水を流通させる冷却管（外管）を設けると共に、上記ＥＧＲ配管の周方向複数箇所に軸線方向に延びる凹部を形成することによって上記ＥＧＲ配管を横断面波状に形成し、それによってＥＧＲ配管の表面積を増大させて冷却効率を高めるが提案されているが、上記のＥＧＲ配管内を流れるＥＧＲガスは単にそのまま通過するだけなので、必ずしも充分な冷却効果が得られない等の問題があった。
【０００６】
【発明が解決しようとする課題】
本発明は上記の問題点に鑑みて提案されたもので、簡単な構成により、冷却効果の優れたＥＧＲガス冷却装置を提供することを目的とする。
【０００７】
【課題を解決するための手段】
上記の目的を達成するために本発明によるＥＧＲガス冷却装置は、以下の構成としたものである。即ち、エンジンの排気系から排出された排気ガスの一部をＥＧＲガスとしてエンジンの吸気系に再循環させるＥＧＲ配管の外周に外管を設け、その外管とＥＧＲ配管との間に冷却水を流通させて上記ＥＧＲ配管内を通る排気ガスを冷却するＥＧＲガス冷却装置において、上記ＥＧＲ配管内に狭窄部を設けたことを特徴とする。
【０００８】
上記ＥＧＲ配管には、必要に応じて上記外管の内方において大径の膨出部を形成し、その膨出部に狭窄部を設けるようにしてもよい。また上記の狭窄部としては、それによって例えばＥＧＲ配管１の軸線方向におけるそれと直交方向の内空横断面積または内空横断面形状を変化させ得る構成であればよく、具体的には例えばＥＧＲ配管にリング状または螺旋状もしくは突起状の突出部を設ける、あるいは複数個の貫通孔を有する仕切板、もしくは周面に複数個の貫通孔を有する筒体を、前記ＥＧＲ配管内に設けるようにしてもよい。
【０００９】
【発明の実施の形態】
以下、本発明によるＥＧＲガス冷却装置を図に示す実施形態に基づいて具体的に説明する。
【００１０】
図１は本発明によるＥＧＲガス冷却装置の一実施形態を示すもので、図において、１はＥＧＲ配管で、その一端側はフランジ継手２および図に省略した接続管等を介してエンジンの排気マニホールド等に連通接続され、他端はフランジ継手３および図に省略した接続管等を介してエンジンの吸気マニホールド等に連通接続されている。
【００１１】
上記ＥＧＲ配管１は、本実施形態においては、その中間部にハイドロフォーム加工等により両端部１ａ，１ｂよりも大径の膨出部（拡径部）１ｃを形成し、その膨出部１ｃの軸線方向略中央部に、狭窄部Ａとして配管１の内方に突出するリング状の突出部（縮径部）１ｄを設けたものである。その突出部１ｄは、本実施形態においては上記両端部１ａ，１ｂの内径と略同径に形成したものであるが、両端部１ａ，１ｂの内径よりも小さく、或いは大きく形成してもよい。
【００１２】
上記ＥＧＲ配管１の周囲には、上記膨出部１ｃおよび突出部１ｄを覆うようにして外管４を上記配管１と略同心状に設けることによって、上記配管１と外管４との間に冷却水を流通させるための通路Ｓを形成したもので、上記外管４の両端部は、図の場合は配管１と外管４とに溶接等で一体的に固着したリング状の端板４ａ，４ｂで閉塞した構成であるが、外管４のいずれか一方もしくは両方の端部を絞り加工して閉塞するようにしてもよい。
【００１３】
図中、５は冷却水導入管で、その導入管５に図に省略した連通管等を接続してエンジン冷却水の一部を上記配管１と外管４との間の上記通路Ｓ内に導入した後、配水管６から図に省略した連通管等を介してエンジン冷却水の管路内等に帰還させる構成である。７は上記配管１と外管４との間に残留する空気を排出させるための抜気管である。なお、図中の６を上記通路Ｓ内への冷却水導入管とし、５を配水管としてもよい。
【００１４】
なお上記のＥＧＲガス冷却装置を構成する部材の材質等は適宜であるが、好ましくはステンレス等の耐食性および耐熱性のよい金属を用いるとよく、特にＥＧＲ配管１としては、ＳＵＳ４３６を用いると、耐食性および耐熱性がよいだけでなく、熱伝導性がよく、冷却効率を向上させることができる。
【００１５】
上記の構成において、ＥＧＲ配管１と外管４との間の冷却水通路Ｓ内に冷却水を流通させた状態で、図に省略したエンジンからの排気ガスの一部をＥＧＲガスとして上記ＥＧＲ配管１の一端側（図の場合は左側の端部１ａ側）から該配管１内に導入すると、本実施形態においては、ＥＧＲ配管１の中間部に両端部１ａ，１ｂよりも大径の膨出部１ｃが形成されているので、先ず、その膨出部１ｃでＥＧＲガスが膨張する。その際、ＥＧＲガスの大部分は、図１（ａ）に矢印で示すようにＥＧＲ配管１の半径方向外方に拡がる傾向となり、上記膨出部１ｃの内面に押し付けられるようにして上記内面に沿って移動する。次いで、ＥＧＲガスは狭窄部Ａとしての突出部１ｄで圧縮された後、再び膨出部１ｃで膨張して膨出部１ｃの内面に向かって拡散し、その内面に押し付けられるようにして移動する。それによって、ＥＧＲガス中の熱が配管１の内面に順次良好に伝達され、上記配管１と外管４との間に流通する冷却水で効率よく冷却することができるものである。なお、その冷却されたＥＧＲガスは上記ＥＧＲ配管１の他端側（図の場合は右側の端部１ｂ側）から図に省略した接続管等を介してエンジンの吸気マニホールド等に導かれる。
【００１６】
上記のように本発明においては、ＥＧＲ配管１の途中に狭窄部Ａとしての突出部１ｄを設けたから、その突出部１ｄでＥＧＲガスが圧縮されたのち膨張し、その膨張する際のＥＧＲガスが拡がる作用でＥＧＲガス中の熱を配管１に効率よく伝達して冷却することができる。また図示例のように外管４の内側のＥＧＲ配管１に膨出部１ｃを形成すると、ＥＧＲ配管１の表面積が増し、そのＥＧＲ配管１と外管４との間の冷却水通路Ｓ内を流れる冷却水との接触面積が増大して冷却効果を更に向上させることが可能となる。
【００１７】
なお上記実施形態は、突出部１ｄの両側の膨出部１ｃを直管状に形成したが、例えば図２のように膨出部１ｃを滑らかな紡錘形状に形成してもよい。このように構成すると、ＥＧＲガスが突出部１ｄを通過する際の上記の膨張・拡散機能を維持した上でＥＧＲガスの流れをスムーズにすることができると共に、ＥＧＲガスが膨出部１ｃから突出部１ｄに移動する際に膨出部１ｃ内面へのＥＧＲガスの接触頻度や接触圧力等が増大して冷却効果を高めることができる。
【００１８】
上記のような狭窄部を構成する突出部１ｄは、例えば図３のようにＥＧＲ配管１の軸線方向に複数個設けてもよく、その場合、突出部１ｄの大きさ形状等は図のように適宜異ならせてもよく、あるいは同一の大きさ形状に形成してもよい。上記のように突出部１ｄを複数個設けると、ＥＧＲガスが膨張・拡散する回数が増えて冷却効果が向上すると共に、配管１の表面積が増し、その配管１と外管４との間の冷却水通路Ｓ内を流れる冷却水との接触面積が増大して冷却効果を更に向上させることができる。
【００１９】
また上記のような突出部１ｄは、例えば図４に示すように螺旋状に形成してもよく、そのようにすると、配管１内を流れるＥＧＲガスを前記と同様の作用で配管１の内面側に押し付けるように移動付勢することができると共に、ＥＧＲガスが螺旋状の突出部１ｄに沿って旋回し、その遠心力でＥＧＲガスが配管１の内面に更に強く押し付けられて、より効果的に冷却することが可能となる。
【００２０】
さらに前記の狭窄部Ａを形成する手段として上記のようなリング状もしくは螺旋状の突出部１ｄを設ける代わり例えば図５に示すようにＥＧＲ配管１に突起状の突出部１ｄを設けてもよく、その場合にも上記と同様の作用効果が得られる。なお上記の突起状の突出部１ｄとして図の場合は略半球状の突出部１ｄを、ＥＧＲ配管１の膨出部１ｃの軸線方向ほぼ中央部において周方向に４つ設けたが、その形状や配置位置および個数等は適宜である。
【００２１】
また上記のような突出部１ｄ等による狭窄部Ａを設けたＥＧＲ配管１の周面に、例えば図６（ａ）および（ｂ）のように多数の小突起１ｅを設けるようにしてもよく、そのような小突起１ｅを設けると、上記配管１の表面積、ひいては配管１と外管４との間の通路Ｓ内を流れる冷却水との接触面積が増大して冷却効果を更に向上させることができる。後述する実施形態においても同様である。なお、上記図６の場合は小突起１ｅをＥＧＲ配管１の内側に突出させたが、ＥＧＲ配管１の外側に突出させてもよい。
【００２２】
以上の実施形態は狭窄部Ａを形成する手段としてＥＧＲ配管１の周面に突出部１ｄを形成したが、例えば図７に示すように多数の貫通孔１１ａ，１２ａを有する仕切板１１，１２をＥＧＲ配管１内に設けてもよい。その仕切板１１，１２および貫通孔１１ａ，１２ａの配置位置や個数は適宜であるが、図の場合はＥＧＲ配管１の膨出部１ｃ内の上流側と下流側とに仕切板１１，１２を設け、その各仕切板１１，１２の周縁部に複数個の貫通孔１１ａ，１２ａを設けた構成である。また一方の仕切板１１の貫通孔１１ａは円形に、他方の仕切板１２の貫通孔１２ａは仕切板１２の周縁に沿う円弧状の長孔に形成してものであるが、それらの形状は適宜である。
【００２３】
上記のように構成すると、ＥＧＲ配管１の一端１ａ側から導入されたＥＧＲガスは、膨出部１ｃで膨張した後、仕切板１１，１２の貫通孔１１ａ，１２ａを経てＥＧＲ配管１の他端１ｂ側から排出されるもので、その際、上記貫通孔１１ａ，１２ａを通過する過程で、ＥＧＲガスが収縮および膨張を繰り返すと共に、上記上記貫通孔１１ａ，１２ａは仕切板１１，１２の周縁部に形成されているので、その各貫通孔１１ａ，１２ａを通過したＥＧＲガスはＥＧＲ配管１の内面に沿って移動する。それによって、ＥＧＲガス中の熱が配管１に順次良好に伝達され、上記配管１と外管４との間に流通する冷却水で効率よく冷却される。
【００２４】
さらに前記の狭窄部Ａとして例えば図８に示すように周面に多数の貫通孔１３ｃを有する筒体１３をＥＧＲ配管１内に設けてもよい。その筒体１３は、その一端１３ａ側が開口し、その開口側の端部をＥＧＲ配管１の端部１ａの内面に嵌合固着すると共に、他端１３ｂを図８（ｂ）のように十字状に押し潰すことによって閉塞した構成である。
【００２５】
上記のように構成すると、ＥＧＲ配管１の一端１ａ側から導入されたＥＧＲガスは、上記筒体１３内を通って、その周面の貫通孔１３ｃからＥＧＲ配管１の内面に向かって排出された後、そのＥＧＲ配管１の内面近傍を通ってＥＧＲ配管１の他端１ｂ側から排出されるもので、そのとき、上記ＥＧＲガスがＥＧＲ配管１の内面近傍を通ることによってＥＧＲガス中の熱が配管１に順次良好に伝達され、上記配管１と外管４との間に流通する冷却水で効率よく冷却することができるものである。
【００２６】
なお上記各実施形態は、ＥＧＲ配管１の中間部に大径の膨出部１ｃを形成したが、そのような膨出部１ｃを設けることなく、ＥＧＲ配管１をその略全長にわたって略同一径とし、その配管１の途中に前記各実施形態のような狭窄部Ａを設けるようにしてもよい。
【００２７】
【発明の効果】
以上のように本発明によるＥＧＲガス冷却装置は、ＥＧＲ配管１内に狭窄部Ａを設けたから、その狭窄部ＡによってＥＧＲ配管１の軸線方向におけるそれと直交方向の内空横断面積または内空横断面形状を変化させることが可能となり、その狭窄部ＡをＥＧＲガスが通過する際に、該ＥＧＲガスが一旦収縮もしくは圧縮されたのちに膨張し、その膨張力でＥＧＲガスがＥＧＲ配管１の内面に押し付けられるように順次接触してＥＧＲガス中の熱がＥＧＲ配管１に良好に伝達される。そして、そのＥＧＲ配管１に伝達された熱は、上記ＥＧＲ配管１と外管４との間に流通する冷却水によって効率よく冷却することができるもので、ＥＧＲ配管内に狭窄部を設けるだけの極めて簡単な構成によって冷却効率の優れたＥＧＲガス冷却装置を提供できるものである。
【図面の簡単な説明】
【図１】（ａ）は本発明によるＥＧＲガス冷却装置の一実施形態を示す縦断面図。
（ｂ）は（ａ）におけるｂ−ｂ線断面図。
【図２】本発明によるＥＧＲガス冷却装置の他の実施形態を示す縦断面図。
【図３】本発明によるＥＧＲガス冷却装置の他の実施形態を示す縦断面図。
【図４】本発明によるＥＧＲガス冷却装置の他の実施形態を示す縦断面図。
【図５】（ａ）は本発明によるＥＧＲガス冷却装置の他の実施形態を示す縦断面図。
（ｂ）は（ａ）におけるｂ−ｂ線断面図。
【図６】（ａ）および（ｂ）はＥＧＲ配管の周面に小突起を設けた例の縦断面図。
【図７】（ａ）は本発明によるＥＧＲガス冷却装置の他の実施形態を示す縦断面図。
（ｂ）は（ａ）におけるｂ−ｂ線断面図。
（ｃ）は（ａ）におけるｃ−ｃ線断面図。
【図８】（ａ）は本発明によるＥＧＲガス冷却装置の他の実施形態を示す縦断面図。
（ｂ）は（ａ）におけるｂ−ｂ線断面図。
【符号の説明】
１　ＥＧＲ配管
１ａ、１ｂ　端部
１ｃ　膨出部
１ｄ　突出部
１ｅ　小突起
２、３　フランジ継手
４　外管
４ａ，４ｂ　端板
５　冷却水導入管
６　配水管
７　抜気管
Ａ　狭窄部
Ｓ　冷却水通路[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a so-called EGR gas cooling device that recirculates a part of exhaust gas discharged from an exhaust system of an engine of an automobile or the like as EGR gas to an intake system of the engine.
[0002]
[Prior art]
Conventionally, a part of the exhaust gas discharged from the exhaust system of the engine is recirculated to the intake system of the engine as EGR gas for the purpose of reducing nitrogen oxides in the exhaust gas discharged from the engine as described above. It is known to provide a so-called exhaust gas recirculation (EGR) device that causes the exhaust gas recirculation. In this case, the EGR gas to be recirculated to the intake system needs to be appropriately cooled. Conventionally, an EGR gas cooling device including a cooling means is provided in the middle of the EGR pipe.
[0003]
As the EGR gas cooling device as described above, for example, as disclosed in Japanese Patent Application Laid-Open No. H11-193998 and Japanese Patent Application Laid-Open No. H11-193939, an EGR pipe through which the EGR gas flows is constituted by a large number of pipes, and It is known to cool the EGR gas by flowing cooling water between an outer pipe covering the EGR pipe and the EGR pipe. However, the structure is complicated, the production cost is increased, and the size of the apparatus is increased, so that the weight of the vehicle is reduced. There is a problem such as an increase in
[0004]
Therefore, it has been proposed to provide a cylindrical outer water cooling jacket for flowing cooling water around the outer periphery of the EGR pipe and to provide a thin tubular inner water cooling jacket inside the EGR pipe as disclosed in Japanese Patent Application Laid-Open No. 2001-207919. . However, providing a thin tubular inner water cooling jacket in the EGR pipe has problems such as cumbersome and troublesome, and the production cost increases.
[0005]
Further, for example, as in Japanese Patent Application Laid-Open No. 2000-265908, the EGR pipe is formed as a single pipe, and a cooling pipe (outer pipe) for flowing cooling water is provided around the outer circumference of the EGR pipe. It has been proposed that the EGR pipe is formed in a wavy cross section by forming an extending recess, thereby increasing the surface area of the EGR pipe to increase the cooling efficiency. However, the EGR gas flowing through the EGR pipe is simply There was a problem that a sufficient cooling effect could not always be obtained because the gas passed only as it was.
[0006]
[Problems to be solved by the invention]
The present invention has been proposed in view of the above problems, and has as its object to provide an EGR gas cooling device having a simple structure and excellent cooling effect.
[0007]
[Means for Solving the Problems]
To achieve the above object, an EGR gas cooling device according to the present invention has the following configuration. That is, an outer pipe is provided on the outer periphery of an EGR pipe for recirculating a part of the exhaust gas discharged from the exhaust system of the engine as EGR gas to the intake system of the engine, and cooling water is provided between the outer pipe and the EGR pipe. An EGR gas cooling device that cools exhaust gas flowing through the EGR pipe is characterized in that a constriction is provided in the EGR pipe.
[0008]
The EGR pipe may have a large-diameter bulge formed inside the outer pipe as necessary, and a narrowed portion may be provided in the bulge. Further, the constricted portion may have a configuration that can change the inner cross-sectional area or the inner cross-sectional shape in a direction orthogonal to that in the axial direction of the EGR pipe 1, for example. A ring-shaped or spiral-shaped or protruding projection may be provided, or a partition plate having a plurality of through holes, or a cylindrical body having a plurality of through holes on a peripheral surface may be provided in the EGR pipe. Good.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an EGR gas cooling device according to the present invention will be specifically described based on an embodiment shown in the drawings.
[0010]
FIG. 1 shows an embodiment of an EGR gas cooling apparatus according to the present invention. In the figure, reference numeral 1 denotes an EGR pipe, one end of which is connected to a flange joint 2 and an exhaust manifold of an engine via a connection pipe and the like omitted in the figure. The other end is connected to the intake manifold of the engine and the like via the flange joint 3 and a connection pipe not shown in the drawing.
[0011]
In the present embodiment, in the present embodiment, the EGR pipe 1 has a bulged portion (increased diameter portion) 1c having a diameter larger than both end portions 1a and 1b formed at an intermediate portion by hydroforming or the like. A ring-shaped protruding portion (reduced-diameter portion) 1d that protrudes inward of the pipe 1 as a constricted portion A is provided at a substantially central portion in the axial direction. In the present embodiment, the projecting portion 1d is formed to have substantially the same diameter as the inner diameters of both ends 1a and 1b, but may be formed to be smaller or larger than the inner diameters of both ends 1a and 1b.
[0012]
Around the EGR pipe 1, an outer pipe 4 is provided substantially concentrically with the pipe 1 so as to cover the bulging portion 1 c and the protruding portion 1 d, so that the outer pipe 4 is provided between the pipe 1 and the outer pipe 4. A passage S for flowing cooling water is formed, and both ends of the outer pipe 4 are ring-shaped end plates 4a integrally fixed to the pipe 1 and the outer pipe 4 by welding or the like in the case of the figure. , 4b, but one or both ends of the outer tube 4 may be drawn and closed.
[0013]
In the drawing, reference numeral 5 denotes a cooling water introduction pipe, which is connected to a communication pipe or the like omitted from the drawing to connect the introduction pipe 5 to a part of the engine cooling water in the passage S between the pipe 1 and the outer pipe 4. After the introduction, the cooling water is returned from the water distribution pipe 6 to the inside of the pipe of the engine cooling water via a communication pipe or the like not shown in the drawing. Reference numeral 7 denotes a vent pipe for discharging air remaining between the pipe 1 and the outer pipe 4. Note that 6 in the drawing may be a cooling water introduction pipe into the passage S, and 5 may be a water distribution pipe.
[0014]
In addition, although the material etc. of the member which comprises the said EGR gas cooling apparatus are suitable, Preferably it is good to use the metal with good corrosion resistance and heat resistance, such as stainless steel, Especially when using SUS436 as the EGR pipe 1, In addition to good heat resistance, heat conductivity is good and cooling efficiency can be improved.
[0015]
In the above configuration, in a state where the cooling water is circulated in the cooling water passage S between the EGR pipe 1 and the outer pipe 4, a part of the exhaust gas from the engine not shown is used as the EGR gas and the EGR pipe is used. When the tube 1 is introduced into the pipe 1 from one end side (the left end 1a side in the figure), in the present embodiment, the bulge having a larger diameter than the both ends 1a, 1b is formed in the middle of the EGR pipe 1. Since the portion 1c is formed, first, the EGR gas expands at the bulging portion 1c. At this time, most of the EGR gas tends to spread outward in the radial direction of the EGR pipe 1 as indicated by an arrow in FIG. 1A, and is pressed against the inner surface of the bulging portion 1c so as to be spread on the inner surface. Move along. Next, the EGR gas is compressed by the protruding portion 1d as the constricted portion A, then expanded again at the protruding portion 1c, diffuses toward the inner surface of the protruding portion 1c, and moves so as to be pressed against the inner surface. . Thereby, the heat in the EGR gas is successively and well transmitted to the inner surface of the pipe 1, and can be efficiently cooled by the cooling water flowing between the pipe 1 and the outer pipe 4. The cooled EGR gas is guided from the other end of the EGR pipe 1 (the right end 1b in the case of the drawing) to an intake manifold or the like of the engine via a connection pipe or the like omitted from the drawing.
[0016]
As described above, in the present invention, since the protruding portion 1d as the constricted portion A is provided in the middle of the EGR pipe 1, the EGR gas is compressed and expanded at the protruding portion 1d. By the spreading action, heat in the EGR gas can be efficiently transmitted to the pipe 1 for cooling. Further, when the bulging portion 1c is formed in the EGR pipe 1 inside the outer pipe 4 as shown in the illustrated example, the surface area of the EGR pipe 1 increases, and the inside of the cooling water passage S between the EGR pipe 1 and the outer pipe 4 is formed. The contact area with the flowing cooling water is increased, and the cooling effect can be further improved.
[0017]
In the above embodiment, the bulges 1c on both sides of the protrusion 1d are formed in a straight tubular shape. However, for example, the bulge 1c may be formed in a smooth spindle shape as shown in FIG. With this configuration, the flow of the EGR gas can be made smooth while maintaining the above-described expansion / diffusion function when the EGR gas passes through the protruding portion 1d, and the EGR gas protrudes from the protruding portion 1c. When moving to the portion 1d, the frequency of contact of the EGR gas with the inner surface of the bulging portion 1c, the contact pressure, and the like are increased, and the cooling effect can be enhanced.
[0018]
A plurality of protrusions 1d constituting the constricted portion as described above may be provided in the axial direction of the EGR pipe 1 as shown in FIG. 3, for example. In this case, the size and shape of the protrusions 1d are as shown in the figure. They may be different as appropriate, or may be formed in the same size and shape. When a plurality of protrusions 1d are provided as described above, the number of times that the EGR gas expands and diffuses increases, thereby improving the cooling effect, increasing the surface area of the pipe 1, and cooling the pipe 1 between the pipe 1 and the outer pipe 4. The contact area with the cooling water flowing in the water passage S is increased, and the cooling effect can be further improved.
[0019]
Further, the above-mentioned protrusion 1d may be formed in a spiral shape, for example, as shown in FIG. 4, and in such a case, the EGR gas flowing through the inside of the pipe 1 is subjected to the same operation as described above to the inner side of the pipe 1 And the EGR gas is swirled along the helical protrusion 1d, and the centrifugal force causes the EGR gas to be more strongly pressed against the inner surface of the pipe 1, thereby more effectively. It becomes possible to cool.
[0020]
Further, instead of providing the ring-shaped or spiral-shaped protrusion 1d as a means for forming the constricted portion A, a protrusion-like protrusion 1d may be provided on the EGR pipe 1 as shown in FIG. 5, for example. In this case, the same operation and effect as described above can be obtained. In the case of the figure, four substantially hemispherical protrusions 1d are provided in the circumferential direction substantially at the center of the bulging portion 1c of the EGR pipe 1 in the axial direction as the above-mentioned protrusion-like protrusions 1d. The arrangement position, the number, and the like are appropriate.
[0021]
In addition, a large number of small projections 1e may be provided on the peripheral surface of the EGR pipe 1 provided with the constricted portion A by the above-described projections 1d, for example, as shown in FIGS. 6 (a) and 6 (b). Providing such small projections 1e increases the surface area of the pipe 1 and the contact area with the cooling water flowing in the passage S between the pipe 1 and the outer pipe 4 to further improve the cooling effect. it can. The same applies to embodiments described later. In the case of FIG. 6 described above, the small protrusion 1 e is projected inside the EGR pipe 1, but may be projected outside the EGR pipe 1.
[0022]
In the above-described embodiment, the protruding portion 1d is formed on the peripheral surface of the EGR pipe 1 as a means for forming the constricted portion A. However, for example, the partition plates 11 and 12 having a large number of through holes 11a and 12a as shown in FIG. It may be provided in the EGR pipe 1. Arrangement positions and numbers of the partition plates 11 and 12 and the through holes 11a and 12a are appropriate, but in the case of the figure, the partition plates 11 and 12 are arranged on the upstream side and the downstream side in the bulging portion 1c of the EGR pipe 1. In this configuration, a plurality of through holes 11a and 12a are provided in a peripheral portion of each of the partition plates 11 and 12. Also, the through hole 11a of one partition plate 11 is formed in a circular shape, and the through hole 12a of the other partition plate 12 is formed in an arc-shaped long hole along the peripheral edge of the partition plate 12. It is.
[0023]
With the above configuration, the EGR gas introduced from one end 1a side of the EGR pipe 1 expands in the bulging portion 1c, and then passes through the through holes 11a and 12a of the partition plates 11 and 12, and the other end of the EGR pipe 1 The EGR gas repeatedly contracts and expands in the process of passing through the through holes 11a, 12a, and the through holes 11a, 12a are formed at the peripheral portions of the partition plates 11, 12. Therefore, the EGR gas that has passed through the through holes 11 a and 12 a moves along the inner surface of the EGR pipe 1. Thereby, the heat in the EGR gas is sequentially and well transmitted to the pipe 1, and is efficiently cooled by the cooling water flowing between the pipe 1 and the outer pipe 4.
[0024]
Further, a cylindrical body 13 having a large number of through holes 13c on the peripheral surface as shown in FIG. 8, for example, may be provided in the EGR pipe 1 as the constricted portion A. The cylindrical body 13 is open at one end 13a side, the open end is fitted and fixed to the inner surface of the end 1a of the EGR pipe 1, and the other end 13b is cross-shaped as shown in FIG. This is a configuration that is closed by crushing.
[0025]
With the above configuration, the EGR gas introduced from the one end 1a side of the EGR pipe 1 passes through the inside of the cylindrical body 13 and is discharged from the through hole 13c of the peripheral surface toward the inner surface of the EGR pipe 1. Thereafter, the gas is discharged from the other end 1b side of the EGR pipe 1 through the vicinity of the inner surface of the EGR pipe 1. At this time, the heat in the EGR gas is reduced by passing the EGR gas near the inner surface of the EGR pipe 1. The cooling water is transmitted to the pipe 1 sequentially and efficiently, and can be efficiently cooled by the cooling water flowing between the pipe 1 and the outer pipe 4.
[0026]
In each of the above embodiments, the large-diameter bulging portion 1c is formed in the middle portion of the EGR pipe 1. However, the EGR pipe 1 is formed to have substantially the same diameter over substantially the entire length without providing such a bulging portion 1c. Alternatively, a constricted portion A as in the above embodiments may be provided in the middle of the pipe 1.
[0027]
【The invention's effect】
As described above, in the EGR gas cooling device according to the present invention, since the constricted portion A is provided in the EGR pipe 1, the constricted portion A causes the inner cross section or the inner cross section of the EGR pipe 1 to be orthogonal to the axial direction of the EGR pipe 1. When the EGR gas passes through the constricted portion A, the EGR gas is once contracted or compressed and then expanded, and the expansion force causes the EGR gas to be applied to the inner surface of the EGR pipe 1. The heat in the EGR gas is sequentially contacted so as to be pressed, and the heat in the EGR gas is favorably transmitted to the EGR pipe 1. The heat transmitted to the EGR pipe 1 can be efficiently cooled by the cooling water flowing between the EGR pipe 1 and the outer pipe 4, and only a constriction is provided in the EGR pipe. An EGR gas cooling device having excellent cooling efficiency can be provided by an extremely simple configuration.
[Brief description of the drawings]
FIG. 1A is a longitudinal sectional view showing an embodiment of an EGR gas cooling device according to the present invention.
(B) is a bb line sectional view in (a).
FIG. 2 is a longitudinal sectional view showing another embodiment of the EGR gas cooling device according to the present invention.
FIG. 3 is a longitudinal sectional view showing another embodiment of the EGR gas cooling device according to the present invention.
FIG. 4 is a longitudinal sectional view showing another embodiment of the EGR gas cooling device according to the present invention.
FIG. 5A is a longitudinal sectional view showing another embodiment of the EGR gas cooling device according to the present invention.
(B) is a bb line sectional view in (a).
FIGS. 6A and 6B are longitudinal sectional views of an example in which small projections are provided on a peripheral surface of an EGR pipe.
FIG. 7A is a longitudinal sectional view showing another embodiment of the EGR gas cooling device according to the present invention.
(B) is a bb line sectional view in (a).
(C) is a sectional view taken along line cc in (a).
FIG. 8A is a longitudinal sectional view showing another embodiment of the EGR gas cooling device according to the present invention.
(B) is a bb line sectional view in (a).
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 EGR piping 1a, 1b End part 1c Swelling part 1d Projection part 1e Small protrusion 2, 3, Flange joint 4 Outer pipe 4a, 4b End plate 5 Cooling water introduction pipe 6 Water distribution pipe 7 Vent pipe A Narrow part S Cooling water passage

Claims (5)

エンジンの排気系から排出された排気ガスの一部をＥＧＲガスとしてエンジンの吸気系に再循環させるＥＧＲ配管の外周に外管を設け、その外管とＥＧＲ配管との間に冷却水を流通させて上記ＥＧＲ配管内を通るＥＧＲガスを冷却するＥＧＲガス冷却装置において、上記ＥＧＲ配管内に狭窄部を設けたことを特徴とするＥＧＲガス冷却装置。An outer pipe is provided on the outer periphery of an EGR pipe for recirculating a part of the exhaust gas discharged from the exhaust system of the engine as EGR gas to the intake system of the engine, and cooling water is circulated between the outer pipe and the EGR pipe. An EGR gas cooling device for cooling EGR gas passing through the EGR pipe, wherein a narrowed portion is provided in the EGR pipe. 前記外管の内方において前記ＥＧＲ配管に大径の膨出部を形成し、その膨出部に狭窄部を設けてなる請求項１記載のＥＧＲガス冷却装置。2. The EGR gas cooling device according to claim 1, wherein a large-diameter bulge is formed in the EGR pipe inside the outer pipe, and the bulge is provided with a constriction. 前記狭窄部として、前記ＥＧＲ配管に、リング状または螺旋状もしくは突起状の突出部を設けてなる請求項１または２記載のＥＧＲガス冷却装置。3. The EGR gas cooling device according to claim 1, wherein a ring-shaped, spiral-shaped, or projecting protrusion is provided on the EGR pipe as the constriction. 前記狭窄部として複数個の貫通孔を有する仕切板を前記ＥＧＲ配管内に設けてなる請求項１または２記載のＥＧＲガス冷却装置。3. The EGR gas cooling device according to claim 1, wherein a partition plate having a plurality of through holes as the constriction is provided in the EGR pipe. 4. 前記狭窄部として周面に複数個の貫通孔を有する筒体を前記ＥＧＲ配管内に設けてなる請求項１または２記載のＥＧＲガス冷却装置。3. The EGR gas cooling device according to claim 1, wherein a cylinder having a plurality of through holes on a peripheral surface is provided in the EGR pipe as the constriction.
JP2002210406A 2002-07-19 2002-07-19 EGR gas cooling device Expired - Fee Related JP4236879B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2002210406A JP4236879B2 (en) 2002-07-19 2002-07-19 EGR gas cooling device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2002210406A JP4236879B2 (en) 2002-07-19 2002-07-19 EGR gas cooling device

Publications (2)

Publication Number Publication Date
JP2004053107A true JP2004053107A (en) 2004-02-19
JP4236879B2 JP4236879B2 (en) 2009-03-11

Family

ID=31933916

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2002210406A Expired - Fee Related JP4236879B2 (en) 2002-07-19 2002-07-19 EGR gas cooling device

Country Status (1)

Country Link
JP (1) JP4236879B2 (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009034833A1 (en) * 2007-09-10 2009-03-19 Usui Kokusai Sangyo Kaisha Limited Urea water piping structure for exhaust purification device for internal combustion engine
JP2010266141A (en) * 2009-05-15 2010-11-25 Tlv Co Ltd Heat exchanger
JP2010266142A (en) * 2009-05-15 2010-11-25 Tlv Co Ltd Vaporization cooler
JP2011191034A (en) * 2010-03-16 2011-09-29 Showa Denko Kk Dual-pipe heat exchanger
JP2011530687A (en) * 2008-08-06 2011-12-22 ニルソン、スベン・メルカー Channel system
JP2012127623A (en) * 2010-12-17 2012-07-05 Denso Corp Multi-pipe heat exchanger
CN104990441A (en) * 2015-07-15 2015-10-21 宁波高新区金杉新能源科技有限公司 Spiral heat exchange pipe
WO2016056349A1 (en) * 2014-10-06 2016-04-14 フタバ産業株式会社 Heat exchanger
JPWO2016139711A1 (en) * 2015-03-02 2017-04-27 中国電力株式会社 Heat exchange device, fuel gas generator
JP2019196869A (en) * 2018-05-10 2019-11-14 株式会社ニチリン Double-pipe heat exchanger
CN113404604A (en) * 2020-03-17 2021-09-17 本田技研工业株式会社 Cylinder head of multi-cylinder engine

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009034833A1 (en) * 2007-09-10 2009-03-19 Usui Kokusai Sangyo Kaisha Limited Urea water piping structure for exhaust purification device for internal combustion engine
JP2009068348A (en) * 2007-09-10 2009-04-02 Usui Kokusai Sangyo Kaisha Ltd Urea water piping structure for exhaust emission control device of internal combustion engine
JP2011530687A (en) * 2008-08-06 2011-12-22 ニルソン、スベン・メルカー Channel system
JP2010266141A (en) * 2009-05-15 2010-11-25 Tlv Co Ltd Heat exchanger
JP2010266142A (en) * 2009-05-15 2010-11-25 Tlv Co Ltd Vaporization cooler
JP2011191034A (en) * 2010-03-16 2011-09-29 Showa Denko Kk Dual-pipe heat exchanger
JP2012127623A (en) * 2010-12-17 2012-07-05 Denso Corp Multi-pipe heat exchanger
WO2016056349A1 (en) * 2014-10-06 2016-04-14 フタバ産業株式会社 Heat exchanger
JPWO2016139711A1 (en) * 2015-03-02 2017-04-27 中国電力株式会社 Heat exchange device, fuel gas generator
CN104990441A (en) * 2015-07-15 2015-10-21 宁波高新区金杉新能源科技有限公司 Spiral heat exchange pipe
JP2019196869A (en) * 2018-05-10 2019-11-14 株式会社ニチリン Double-pipe heat exchanger
JP7079478B2 (en) 2018-05-10 2022-06-02 株式会社ニチリン Double tube heat exchanger
CN113404604A (en) * 2020-03-17 2021-09-17 本田技研工业株式会社 Cylinder head of multi-cylinder engine
CN113404604B (en) * 2020-03-17 2023-05-30 本田技研工业株式会社 Cylinder head of multi-cylinder engine

Also Published As

Publication number Publication date
JP4236879B2 (en) 2009-03-11

Similar Documents

Publication Publication Date Title
JP2004053107A (en) Egr gas cooling device
US7984752B2 (en) Double-pipe heat exchanger and manufacturing method thereof
JP2006250524A (en) Multi-pipe type heat recovery apparatus
JP2007170271A (en) Multipipe heat exchanger for exhaust gas cooling device
WO2017126083A1 (en) Muffler
US11199116B2 (en) Acoustically tuned muffler
JP2007064514A (en) Heat transfer tube for heat exchanger, and heat exchanger incorporating the heat transfer tube
JP2002054511A (en) Egr cooler
JP2006046846A (en) Double pipe heat exchanger
JP2011214537A (en) Exhaust gas heat recovery device
JP6841849B2 (en) Exhaust pipe
JP2007225137A (en) Multitubular heat exchanger and heat transfer tube for exhaust gas cooling device
JP2005273512A (en) Egr cooler for engine
JP2005055064A (en) Double tube-type heat exchanger and its manufacturing method
JP2002180915A (en) Egr cooler
JP2007085266A (en) Heat exchange apparatus of exhaust system
JP2006266168A (en) Egr cooler
WO2019140893A1 (en) Box-type engine exhaust post-treatment device
KR20190095906A (en) Tube expasion apparatus having spiral groove
JP2001342909A (en) Egr cooler
JP2001012876A (en) Heat exchanger
JP2001342912A (en) Egr cooler
US9149847B2 (en) Indented tube for a heat exchanger
JP2000345925A (en) Egr cooler
JP2001254649A (en) Egr cooler

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20050622

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20080215

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20080227

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20080423

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20081203

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20081217

R150 Certificate of patent or registration of utility model

Ref document number: 4236879

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20111226

Year of fee payment: 3

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20111226

Year of fee payment: 3

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20121226

Year of fee payment: 4

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20131226

Year of fee payment: 5

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

LAPS Cancellation because of no payment of annual fees