JP3855507B2

JP3855507B2 - Heat exchanger for heating

Info

Publication number: JP3855507B2
Application number: JP35815398A
Authority: JP
Inventors: 広之佐藤; 幹夫福岡
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 1998-12-16
Filing date: 1998-12-16
Publication date: 2006-12-13
Anticipated expiration: 2018-12-16
Also published as: JP2000177365A

Description

【０００１】
【発明の属する技術分野】
本発明は電気発熱体を一体化した暖房用熱交換器に関するもので、車両エンジン（内燃機関）にて加熱された温水（エンジン冷却水）を熱源として空気を加熱する車両暖房用熱交換器に用いて好適である。
【０００２】
【従来の技術】
従来、この種の電気発熱体を一体化した熱交換器は、特開平５−６９７３２号公報において提案されている。この従来装置によれば、温水（エンジン冷却水）を熱源として空気を加熱する暖房用熱交換器に電気発熱体を一体化することにより、エンジン始動直後のように温水温度が低いときには、電気発熱体への通電により、電気発熱体の発生熱を空気中に放熱して空気を加熱することができる。
【０００３】
【発明が解決しようとする課題】
ところで、上記公報記載の従来装置では、発熱体素子と電極板から構成される電気発熱体を暖房用熱交換器のコア部と一体ろう付けしているので、高温のろう付け温度（アルミニュウムのろう付けの場合、６００°Ｃ程度）の雰囲気に発熱体が晒されるので、発熱体の電気的特性が著しく損なわれるという不具合がある。
【０００４】
そこで、本出願人においては、偏平チューブとコルゲートフィンとの組み合わせからなる熱交換用コア部の一部の部位に、電気発熱体を設置する暖房用熱交換器において、熱交換用コア部のうち、隣接するコルゲートフィンの折り曲げ頂部相互の間に保持板を配置するとともに、この保持板を、偏平チューブの長手方向に延びる断面Ｕ字状の形状とし、この断面Ｕ字状の保持板の対向する２つの板面相互の間に所定間隔を設定した状態で、この２つの板面をそれぞれコルゲートフィンの折り曲げ頂部に接合し、保持板の開口部から保持板の内部に電気発熱体を電気絶縁して組み付けるようにした暖房用熱交換器を先に出願している（特願平９−２１５０４２号等）。
【０００５】
この先願のものでは、暖房用熱交換器の一体ろう付け後に、保持板の内部に電気発熱体を挿入し組付けできるので、特開平５−６９７３２号公報のように電気発熱体の電気的特性が損なわれる心配はない。
そして、先願のものでは、熱交換用コア部に締付け力を作用させる締結部材（バンド部材）を装着して、電気発熱体を保持板の内部で圧接保持することにより、電気発熱体を断面Ｕ字状の保持板内部で確実に保持できるようにしている。
【０００６】
ここで、先願のものでは締結部材を、偏平チューブの長手方向と直交方向（換言すると、偏平チューブとコルゲートフィンの積層方向）に延びる長尺形状（細長バンド形状）の両端部に引っ掛け部を設けた形状とし、この両端の引っ掛け部を熱交換用コア部の両サイドのサイドプレートに引っ掛ける構成としているが、このような単純な長尺形状（細長バンド形状）に締結部材を形成しただけであると、締結部材が熱交換用コア部への通風の妨げになったり、締結部材からの押圧荷重によりサイドプレートの変形等の不具合が発生することがある。
【０００７】
本発明は上記点に鑑みて、電気発熱体を保持板内部で圧接保持するための締付け力を作用させる締結部材を用いる暖房用熱交換器において、締結部材の装着に伴う不具合の発生を抑制することを目的とする。
【０００８】
【課題を解決するための手段】
上記目的を達成するため、請求項１記載の発明では、熱源流体が流通するチューブ（６）およびこのチューブ（６）に接合されるフィン部材（７）から構成される熱交換用コア部（３）と、
この熱交換用コア部（３）の一部の部位に配置された保持板（１０）と、
この保持板（１０）の内側部に配置される電気発熱体（９）と、
熱交換用コア部（３）に、電気発熱体（９）を保持板（１０）の内部で圧接保持するように締付け力を作用させる締結部材（１９、２０）とを備え、
チューブは偏平チューブ（６）であり、フィン部材はコルゲートフィン（７）であり、
保持板は、隣接するコルゲートフィン（７）の折り曲げ頂部相互の間に配置され、偏平チューブ（６）の長手方向に延びる断面Ｕ字状の保持板（１０）であり、
締結部材（１９、２０）に、熱交換用コア部（３）の端部に係止される両端の引っ掛け部（２２、２３）と、この両端の引っ掛け部（２２、２３）の間に位置して熱交換用コア部（３）の空気通過面に対向する細長本体部（２１）とを形成し、
この細長本体部（２１）の幅を両端の引っ掛け部（２２、２３）の幅より狭くしたことを特徴としている。
【０００９】
これによると、細長本体部（２１）の幅を両端の引っ掛け部（２２、２３）の幅より狭くしているから、締結部材装着に伴う熱交換用コア部（３）の通風抵抗の増加を低減できる。しかも、両端の引っ掛け部（２２、２３）においては幅を広げることにより、熱交換用コア部（３）の端部における押圧荷重の受圧面積を拡大して、熱交換用コア部（３）の端部の変形を抑制できる。
請求項２記載の発明のように、請求項１に記載の暖房用熱交換器において、具体的には、断面Ｕ字状の保持板（１０）を、その閉塞端部（１０ａ）が空気入口側に向き、その開口部（１０ｂ）が空気出口側に向くように配置し、締結部材（１９、２０）は熱交換用コア部（３）の空気出口側の面のみに配置すればよい。
【００１０】
また、請求項３記載の発明では、電気発熱体（９）を保持板（１０）の内部で圧接保持するように締付け力を作用させる締結部材（１９、２０）に、熱交換用コア部（３）の端部に係止される両端の引っ掛け部（２２、２３）と、この両端の引っ掛け部（２２、２３）の間に位置して熱交換用コア部（３）の空気通過面に対向する細長本体部（２１）とを形成し、この細長本体部（２１）に空気通過孔（２９）を開けたことを特徴としている。
【００１１】
これによると、細長本体部（２１）に開けた空気通過孔（２９）を空気が通過できるので、細長本体部（２１）の幅を特別に狭くしなくても、締結部材装着に伴う熱交換用コア部（３）の通風抵抗の増加を低減できる。しかも、両端の引っ掛け部（２２、２３）においては請求項１と同様に幅広に形成できるので、熱交換用コア部（３）の端部における押圧荷重の受圧面積を拡大して、熱交換用コア部（３）の端部の変形を抑制できる。
【００１２】
請求項４に記載の発明では、熱源流体が流通するチューブ（６）およびこのチューブ（６）に接合されるフィン部材（７）から構成される熱交換用コア部（３）と、
この熱交換用コア部（３）の一部の部位に配置された保持板（１０）と、
この保持板（１０）の内側部に配置される電気発熱体（９）と、
熱交換用コア部（３）に、電気発熱体（９）を保持板（１０）の内部で圧接保持するように締付け力を作用させる締結部材（１９、２０）とを備え、
この締結部材（１９、２０）に、熱交換用コア部（３）の端部に係止される両端の引っ掛け部（２２、２３）と、この両端の引っ掛け部（２２、２３）の間に位置して熱交換用コア部（３）の空気通過面に対向する細長本体部（２１）とを形成し、
この細長本体部（２１）の幅を両端の引っ掛け部（２２、２３）の幅より狭くし、
さらに、細長本体部（２１）の途中に細長本体部（２１）の長手方向に弾性変形可能な曲げ部（３０）を形成したことを特徴としている。
これによると、曲げ部（３０）の弾性変形により熱交換用コア部（３）の寸法バラツキを吸収して、締結部材装着作業を容易化できる。
請求項５に記載の発明では、熱交換用コア部（３）は、チューブ（６）の積層方向の両側部に配置されたサイドプレート（８ａ、８ｂ）を備えており、
このサイドプレート（８ａ、８ｂ）は、長手方向に延びる複数の凸状リブ（２６ａ、２６ｂ）と、この複数の凸状リブ（２６ａ、２６ｂ）の間に形成される凹状溝（２７）とを有する凹凸形状であり、
この凹状溝（２７）に両端の引っ掛け部（２２、２３）が係止されるようにしたことを特徴としている。
【００１３】
これによると、サイドプレート（８ａ、８ｂ）自身の強度アップのために形成された凹凸形状の凹状溝（２７）を利用して両端の引っ掛け部（２２、２３）を簡単確実に係止できる。
請求項６に記載の発明では、凸状リブ（２６ａ、２６ｂ）の平坦頂部に、両端の引っ掛け部（２２、２３）の押圧荷重が加わるようにしたことを特徴としている。
【００１４】
これによると、平坦頂部を持つ凸状リブ（２６ａ、２６ｂ）の形状により、引っ掛け部（２２、２３）からの押圧荷重に対して剛性の高い部分を構成できるので、この押圧荷重によってサイドプレート（８ａ、８ｂ）が変形することを良好に抑制できる。
請求項７に記載の発明では、両端の引っ掛け部（２２、２３）にサイドプレート（８ａ、８ｂ）の面から離れる方向に曲げられた曲げ部（２２ａ、２３ａ）が形成されていることを特徴としている。
【００１５】
これによると、曲げ部（２２ａ、２３ａ）がサイドプレート（８ａ、８ｂ）の面から離れているので、締結部材の装着作業時にこの曲げ部（２２ａ、２３ａ）を弾性変形させることが可能となり、熱交換用コア部（３）の寸法バラツキを吸収して、締結部材装着作業を容易化できる。
請求項８に記載の発明では、両端の引っ掛け部（２２、２３）のうち、一方の引っ掛け部（２２）に、締結部材（１９、２０）の内側方向に向いている係止片（２２ｂ）を形成し、他方の引っ掛け部（２３）には、締結部材（１９、２０）の内側方向へ向いている係止部（２３ｂ）と、この係止部（２３ｂ）の先端部から締結部材（１９、２０）の外側方向へ向いている逃げ片（２３ｃ）とを形成したことを特徴としている。
【００１６】
これによると、締結部材の装着作業時に、一方の引っ掛け部（２２）の係止片（２２ｂ）を熱交換用コア部（３）側の係止部に嵌め込んだ後に、他方の引っ掛け部（２３）の係止部（２３ｂ）を熱交換用コア部（３）側の係止部に嵌め込む際に、係止部（２３ｂ）の先端部に外側方向へ向いている逃げ片（２３ｃ）を形成しているから、この逃げ片（２３ｃ）が熱交換用コア部（３）側の係止部に引っ掛かることがなく、係止部（２３ｂ）を熱交換用コア部（３）側の係止部に容易に嵌め込むことができる。
【００１８】
なお、上記各手段の括弧内の符号は、後述する実施形態記載の具体的手段との対応関係を示すものである。
【００１９】
【発明の実施の形態】
以下、本発明の実施形態を図に基づいて説明する。
（第１実施形態）
図１は本発明の第１実施形態を示す車両暖房用熱交換器の全体構造を示すもので、図１において、暖房用熱交換器Ｈは、温水入口側タンク１と、温水出口側タンク２と、この両タンク１、２の間に設けられた熱交換用コア部３とを有している。
【００２０】
温水入口側タンク１には図示しない車両エンジンからの温水（エンジン冷却水）が流入する入口パイプ４が設けられ、温水出口側タンク２には温水を外部へ流出させ、エンジン側に還流させる出口パイプ５が設けられている。なお、本例の熱交換器は図１に示すように左右対称形であるので、温水入口側タンク１と温水出口側タンク２とを左右逆転してもよい。
【００２１】
各タンク１、２はそれぞれタンク本体部１ａ、２ａと、このタンク本体部１ａ、２ａの開口端面を閉じるシートメタル１ｂ、２ｂとからなり、図１の上下方向が長手方向となる周知のタンク構造である。そして、シートメタル１ｂ、２ｂには偏平状のチューブ挿入穴（図示せず）が多数個、図１の上下方向に１列または複数列並んで形成されている。
【００２２】
熱交換用コア部３は暖房用空気の流れ方向（図１の矢印Ａ方向）に対して平行な偏平状に形成された偏平チューブ６を多数個図１の上下方向に並列配置している。そして、この多数個の偏平チューブ６相互の間に波形状に成形されたコルゲートフィン（フィン部材）７を配置し接合している。
偏平チューブ６の両端開口部はシートメタル１ｂ、２ｂのチューブ挿入穴内にそれぞれ挿通され、接合される。また、コア部３の最外側（図１の上下両端部）のコルゲートフィン７のさらに外側にはサイドプレート８ａ、８ｂが配設され、このサイドプレート８ａ、８ｂは最外側のコルゲートフィン７およびシートメタル１ｂ、２ｂに接合される。
【００２３】
さらに、熱交換用コア部３の一部の部位に、偏平チューブ６の代わりに、電気発熱体９を設置している。図１の例では、熱交換用コア部３の３箇所（斜線部）に電気発熱体９を等間隔で設置している。
そして、熱交換用コア部３のうち、電気発熱体９が設置される部位では、図２に示すように隣接するコルゲートフィン７の折り曲げ頂部の間に、偏平チューブ６の長手方向に延びる断面Ｕ字状の保持板１０を配置している。この保持板１０のＵ字状曲げ形状からなる閉塞端部１０ａが熱交換用コア部３の空気入口側に向き、他端側の開口部１０ｂが熱交換用コア部３の空気出口側に向くように、保持板１０の配置方向が設定されている。
【００２４】
また、保持板１０は、その対向する２つの板面１０ｃ、１０ｄ相互の間に所定間隔を設定し、その状態で、この２つの板面１０ｃ、１０ｄをそれぞれコルゲートフィン７の折り曲げ頂部に接合するようにしてある。電気発熱体９は、開口部１０ｂから保持板１０の内部に挿入されて保持される。ここで、電気発熱体９は保持板１０に対して後述の構造により電気的に絶縁して保持される。
【００２５】
なお、保持板１０の全体の厚さは、偏平チューブ６の厚さと同一に設定してあるので、偏平チューブ６の代わりに保持板１０を隣接するコルゲートフィン７相互の間に設置できる。
ところで、本例における熱交換器では、上記各構成部品１〜８ｂのすべてがアルミニュウム（アルミニュウム合金も含む）にて成形されており、また、断面Ｕ字状の保持板１０も同様にアルミニュウムにて成形されている。保持板１０は板厚０．１〜０．５ｍｍ程度の金属薄板であり、また、平板状の保持板１０の幅（暖房空気の流れ方向Ａの幅）はコア部厚さと略同一であり、また、保持板１０の長手方向の寸法（図１の左右方向の寸法）はシートメタル１ｂ、２ｂ間の寸法と略同一である。
【００２６】
次に、電気発熱体９の具体的構造を図２により説明すると、板状の発熱体素子９ａと、この発熱体素子９ａの表裏両面に配置された細長の平板状の電極板９ｂ、９ｃとからなる３層のサンドウイッチ構造になっている。そして、この電極板９ｂ、９ｃの周囲を全周にわたって電気的絶縁材料からなる被覆部材９ｄにより被覆している。ここで、発熱体素子９ａは所定の設定温度（例えば、２００°Ｃ付近）にて抵抗値が急増する正の抵抗温度特性を有する抵抗体材料（例えば、チタン酸バリウム）からなるＰＴＣヒータ素子である。
【００２７】
発熱体素子９ａの両電極板９ｂ、９ｃはアルミニュウム、銅、ステンレス等の導電金属材から成形された金属薄板であり、この両電極板９ｂ、９ｃの長手方向の寸法（図１の左右方向の寸法）は保持板１０と略同一である。そして、この両電極板９ｂ、９ｃの長手方向において発熱体素子９ａは複数箇所、配置されている。発熱体素子９ａと両電極板９ｂ、９ｃは互いに圧接することにより、両者間の電気的導通を得るようにしてある。
【００２８】
被覆部材９ｄが保持板１０の板面１０ｃ、１０ｄの内側面に圧接するようにして、電気発熱体９は保持板１０の内部に組み付けられる。ここで、被覆部材９ｄは保持板１０と両電極板９ｂ、９ｃとの間の電気的な絶縁作用を果たすものであるが、発熱体素子９ａの熱を保持板１０に伝導する役割を果たすため、保持板１０と両電極板９ｂ、９ｃとの間の被覆部材９ｄの厚さは２５μ〜１００μ程度の薄膜のフィルム状にして、良好な熱伝導作用を確保している。この被覆部材９ｄの具体的材質としては、高耐熱性の樹脂（例えば、ポリイミド樹脂等）が好ましい。
【００２９】
上記電極板９ｂは例えば正極側電極板であり、また、上記電極板９ｃは例えば負極側電極板であり、それぞれ電気接続用の端子部が熱交換用コア部３の図１左側端部付近に一体成形されている。この両端子部は本例では熱交換用コア部３の後方側（空気流れ方向Ａの下流側）に突出している。
次に、電気発熱体９の電気接続構造の概要を図１により説明すると、温水入口側タンク１と温水出口側タンク２のうち、本例では、温水出口側タンク２に電気配線用カバー１１が装着されている。この電気配線用カバー１１はポリプロピレンのようなある程度の弾性を有する樹脂（電気絶縁材料）にてタンク２の外形に沿った形状に成形され、そして、一体成形の弾性係止爪片（図示せず）を利用して、タンク２に脱着可能に装着される。
【００３０】
さらに、電気配線用カバー１１には、正極側のコネクタ１２を持つ正極側リード線１３および負極側のコネクタ１４を持つ負極側リード線１５が保持されている。この正極側リード線１３および負極側リード線１５は電気発熱体９の設置数（３本）に対応して３本づつ設けられている。
そして、電気配線用カバー１１には、熱交換用コア部３の後方側（空気流れ方向Ａの下流側）で、かつ、熱交換用コア部３の図１左側端部に突出する３箇所の電気接続部１６、１７、１８を備えている。この３箇所の電気接続部１６、１７、１８では、正極側リード線１３および負極側リード線１５の先端部に電気接続された接続端子片と、上記３箇所の電気発熱体９の電極板９ｂ、９ｃの端子部との電気接続を行う。
【００３１】
なお、正極側のコネクタ１２および負極側のコネクタ１４には、図示しない外部制御回路が電気接続され、この外部制御回路を介して車載電源から各電気発熱体９に通電されるようになっている。
１９、２０はばね性を持つ金属材料からなる締結（バンド）部材であって、熱交換用コア部３の空気出口側の面に配置される。締結部材１９、２０はその両端に折り曲げ形状からなる引掛け部２２、２３を有しており、この引掛け部２２、２３を上下のサイドプレート８ａ、８ｂに引掛けることにより、締結部材１９、２０は上下のサイドプレート８ａ、８ｂの間に装着される。
【００３２】
この締結部材１９、２０の装着により、電気発熱体９を保持板１０の板面１０ｃ、１０ｄ間に圧接保持させる締付け力を熱交換用コア部３に対して作用させることができる。なお、図１では、コア部３の幅方向（図１の左右方向）の２箇所に締結部材１９、２０を装着しているが、この締結部材１９、２０の装着箇所は、コア部３の幅方向の中央部の１箇所のみとしたり、あるいは３箇所以上にしてもよい。
【００３３】
本実施形態では、保持板１０が閉塞端部１０ａを有するＵ字状曲げ形状に形成しているから、保持板１０の開口部１０ｂ側（空気流れ方向Ａの下流側）にのみ締結部材１２を装着するだけで、電気発熱体９の保持固定が可能となる。
次に、上記した暖房用熱交換器Ｈの製造方法を説明すると、まず、最初に図１に示す熱交換器構成を組み付けるコア組付工程を行う。すなわち、熱交換用コア部３のチューブ６とコルゲートフィン７を交互に積層するとともに、熱交換用コア部３のうち、電気発熱体９が設置される部位（図１の３箇所の斜線部）では、隣接するコルゲートフィン７の折り曲げ頂部の間に、チューブ６の長手方向に延びる断面Ｕ字状の保持板１０を配置する。ここで、この保持板１０の対向する２つの板面１０ｃ、１０ｄの間隔を所定間隔に保持するために、この保持板１０の内部に、この所定間隔の板厚を持ったダミー板（図示せず）を挿入する。
【００３４】
このダミー板は後述の一体ろう付けの工程に対する耐熱性を有し、かつアルミニュウムろう付けされない特性を持った材質（例えば、カーボン等）で形成しておく。この組付工程で、タンク１、２、パイプ４、５、およびサイドプレート８ａ、８ｂも組み付けることはもちろんである。
次に、上記のごとくして、組み付けた熱交換器組付体の組付状態を図示しない適宜の治具により保持して、ろう付け炉内に搬入し、ろう付け工程を行う。すなわち、ろう付け炉内で熱交換器組付体をろう付け温度（６００°Ｃ程度）に加熱して、熱交換器各部材のアルミニウムクラッド材のろう材を溶融し、熱交換器組付体の各部材間を一体ろう付けする。
【００３５】
ろう付け終了後に、熱交換器組付体をろう付け炉から搬出し、常温まで熱交換器組付体の温度が低下した後に、電気発熱体９の組付工程を行う。すなわち、電気発熱体９はそれ単独で、熱交換器組付体とは別に、板状の発熱体素子９ａの表裏両面を平板状の電極板９ｂ、９ｃにより挟み込んで３層のサンドウイッチ構造とし、電極板９ｂ、９ｃの周囲を全周にわたって被覆部材９ｄにより被覆しておく。
【００３６】
そして、熱交換器組付体の熱交換用コア部３における３箇所の保持板１０の内側に挿入されているダミー板を取り出す。この後に、保持板１０の対向する２つの板面１０ｃ、１０ｄの内側に形成される所定間隔の空間に、開口部１０ｂから閉塞端部１０ａ側へ向かって電気発熱体９を挿入する。このとき、被覆部材９ｄが保持板１０に圧接するようにして、電気発熱体９を保持板１０内に組み付ける。
【００３７】
この電気発熱体９の組付の後に、締結部材１９、２０の両端の引掛け部を上下のサイドプレート８ａ、８ｂに引掛けて、上下のサイドプレート８ａ、８ｂの間に締結部材１９、２０を熱交換用コア部３が圧縮されるように装着する。
これにより、電気発熱体９を保持板１０の内側に圧接保持させる締付け力を熱交換用コア部３に対して作用させ、電気発熱体９を保持板１０の内側に確実に保持固定できる。また、同時に、電気発熱体９の内部において、発熱体素子９ａの表裏両面が平板状の電極板９ｂ、９ｃに確実に圧接するので、小さな接触抵抗で良好な電気導通状態が得られる。
【００３８】
次に、上記構成において作動を説明する。車室の暖房を行うときには、図示しない空調用送風ファンが作動して、暖房用熱交換器Ｈのコア部３の偏平チューブ６とコルゲートフィン７との間の空隙部に矢印Ａのように暖房用空気が通過する。一方、車両用エンジンのウォータポンプ（図示せず）の作動によりエンジンからの温水（熱源流体）が入口パイプ４より温水入口側タンク１内に流入する。
【００３９】
そして、温水は、入口側タンク１にて多数本の偏平チューブ６に分配され、この偏平チューブ６を並列に流れる間にコルゲートフィン７を介して暖房用空気に放熱する。多数本の偏平チューブ６を通過した温水は、温水出口側タンク２に流入し、ここで集合され、出口パイプ５から温水は熱交換器外部へ流出し、エンジン側に還流する。
【００４０】
一方、暖房時において、エンジンからの温水の温度が設定温度（例えば、８０°Ｃ）より低いときは、外部制御回路からコネクタ１２、１４、リード線１３、１５を介して電気発熱体９の両電極板９ｂ、９ｃ間に車載電源の電圧を加える。これにより、発熱体素子９ａが通電され発熱する。発熱体素子９ａの発熱は電極板９ｂ、９ｃ、被覆部材９ｄ、保持板１０を経て、両側のコルゲートフィン７に伝導されて、このコルゲートフィン７から暖房用空気に放熱される。従って、温水の低温時でも暖房空気を速やかに加熱して即効暖房を行うことができる。
【００４１】
なお、電気発熱体９の発熱体素子９ａは所定の設定温度にて抵抗値が急増する正の抵抗温度特性を有するＰＴＣ素子であるから、周知のごとく、その発熱温度を設定温度に自己制御する自己温度制御機能を備えている。
以上、暖房用熱交換器Ｈの全体構成および作動について説明したが、次に、本発明の特徴とする締結部材１９、２０の具体的形状および装着構造について詳述する。図３は第１実施形態による締結部材１９、２０を示しており、締結部材１９、２０はばね性を持たせるために、ばね鋼を厚さｔ＝１ｍｍ程度の薄板状にプレス成形したものである。
【００４２】
ここで、締結部材１９、２０は、熱交換用コア部３に対向する細長本体部２１と、両端の引っ掛け部２２、２３とから構成されている。そして、両端の引っ掛け部２２、２３は幅寸法Ｗ₁＝例えば１０ｍｍ程度に幅を広げてあり、これに対して、細長本体部２１は幅寸法Ｗ₂＝例えば４ｍｍ程度であり、引っ掛け部２２、２３の幅寸法Ｗ₁に比較して幅を１／２以下に狭めている。
【００４３】
両端の引っ掛け部２２、２３は、それぞれ、細長本体部２１から内側方向（鋭角的な角度方向）に向けられた円弧状曲げ部２２ａ、２３ａを有し、さらに、一方の引っ掛け部２２の先端部には締結部材１９、２０の内側方向へ一層折れ曲がった係止片２２ｂが形成されている。
また、他方の引っ掛け部２３の先端部には締結部材１９、２０の内側方向へ一層突出する円弧状係止部２３ｂが形成され、さらに、この円弧状係止部２３ｂの先端部から締結部材１９、２０の外側方向へに向けられた逃げ片２３ｃが形成されている。
【００４４】
なお、細長本体部２１の途中に１箇所開けられた孔２４は、メッキ工程における締結部材移送用ハンガーの係止孔であって、締結部材１９、２０の表面には防錆、耐食性向上のための表面処理層（メッキ層）が施してある。また、幅の狭い細長本体部２１と幅の広い両端の引っ掛け部２２、２３との間は、幅寸法が徐々に広がる円弧状（Ｒ形状）の接続部２５によって接続している。この接続部２５が円弧状（Ｒ形状）でなく、直線的なテーパ形状でもよいことはもちろんである。
【００４５】
次に、図４は締結部材１９、２０を係止するサイドプレート８ａ、８ｂの形状を例示するもので、図４の下側は熱交換用コア部３に対向する面であり、サイドプレート８ａ、８ｂには、その長手方向に延びる凹凸状のリブ形状が成形され、このリブ形状により断面係数を大きくして剛性を高めている。そして、サイドプレート８ａ、８ｂには、長手方向に延びる２つの平行な凸状リブ２６ａ、２６ｂの間（幅方向の中央部）に凹状溝２７が形成されている。
【００４６】
締結部材１９、２０は、サイドプレート８ａ、８ｂの凹凸状のリブ形状を利用してサイドプレート８ａ、８ｂに装着するようになっている。すなわち、締結部材１９、２０の装着作業に際しては、締結部材１９、２０の一方の端部の係止片２２ｂを図５に示すように、上下のサイドプレート８ａ、８ｂのうち、いずれか一方のサイドプレートの凹状溝２７内に嵌め込み、係止する。
【００４７】
その後、細長本体部２１を手に持って作業者が押圧力を加えることにより、締結部材１９、２０の逃げ片２３ｃ側の端部を弾性変形させながら、逃げ片２３ｃに隣接する円弧状係止部２３ｂを他方のサイドプレートの凹状溝２７内に嵌め込み、係止する。
以上の操作により、サイドプレート８ａ、８ｂの凹状溝２７を利用して、締結部材１９、２０を簡単にサイドプレート８ａ、８ｂに装着できる。ここで、締結部材１９、２０の両端の引っ掛け部２２、２３において、曲げ部２２ａ、２３ａの部位は図５に拡大図示するように、サイドプレート８ａ、８ｂの側面端部２８から所定量開離して弾性変形しやすいばね部を構成するので、この曲げ部２２ａ、２３ａの弾性変形によってコア部３の寸法ばらつきを吸収して、締結部材１９、２０の装着時の作業性を改善できる。
【００４８】
さらに、締結部材１９、２０の両端の引っ掛け部２２、２３のうち、後から嵌め込みを行う側の引っ掛け部２３には、締結部材１９、２０の外側方向へに向けられた逃げ片２３ｃを円弧状係止部２３ｂの先端側に備えているから、逃げ片２３ｃが凸状リブ２６ａ、２６ｂに引っ掛かることがなく、円弧状係止部２３ｂの嵌め込み作業を容易に行うことができ、締結部材１９、２０の装着作業を一層容易化できる。
【００４９】
そして、締結部材１９、２０が上下のサイドプレート８ａ、８ｂの間に装着された状態では、締結部材１９、２０の両端の引っ掛け部２２、２３が図３（ｂ）に示すように装着前の実線位置から装着後の２点鎖線位置まで弾性変形して、両端の引っ掛け部２２、２３間の間隔が拡大する。その結果、両端の引っ掛け部２２、２３の間に弾性反力が発生し、熱交換用コア部３に対して圧縮方向の締め付け力を作用させることができる。
【００５０】
しかも、締結部材１９、２０のうち、コア部３の空気通過面に対向する細長本体部２１の幅を両端の引っ掛け部２２、２３より狭くすることにより、コア部３の空気通過面での通風抵抗増加を最小限に抑制できる。
さらに、本実施形態によると、次の利点もある。すなわち、本発明者らは，電気発熱体一体組み込み方式の暖房用熱交換器Ｈの開発に際して、その開発当初においては、締結部材１９、２０の両端の引っ掛け部２２、２３をサイドプレート８ａ、８ｂの側面端部２８に係止するものを試作してみたが、この場合は、締結部材１９、２０による締め付け力が側面端部２８に集中して、サイドプレート８ａ、８ｂの変形、さらには、このサイドプレート８ａ、８ｂの変形部に接合されるコルゲートフィン７の座屈等を引き起こすという不具合が生じた。
【００５１】
しかし、本実施形態によると、締結部材１９、２０の両端の引っ掛け部２２、２３の幅を細長本体部２１より広く（２倍以上に拡大）して、サイドプレート８ａ、８ｂへの応力集中を抑えるとともに、引っ掛け部２２、２３とサイドプレート８ａ、８ｂとの係止位置を側面端部２８でなく、凹状溝２７に変更して、締結部材１９、２０の押圧荷重が図５の矢印Ｂに示すごとく凸状リブ２６ａの平坦頂部に加わるようにしている。
【００５２】
この平坦頂部を持つ凸状リブ２６ａの形状により、引っ掛け部２２、２３からの押圧荷重に対して剛性の高い部分（断面係数の大きい部分）を構成できるので、この押圧荷重によってサイドプレート８ａ、８ｂが変形することを良好に抑制できる。従って、サイドプレート８ａ、８ｂの変形によるコルゲートフィン７の座屈等も防止できる。
【００５３】
（第２実施形態）
図６は第２実施形態であり、第１実施形態では、締結部材１９、２０の両端の引っ掛け部２２、２３の形状を別形状、すなわち、一方の引っ掛け部２２側では係止片２２ｂを形成し、他方の引っ掛け部２３側では円弧状係止部２３ｂと逃げ片２３ｃとを形成しているが、第２実施形態では、図６に示すように、両端の引っ掛け部２２、２３を同一形状（両方とも同一形状の円弧状係止部２２ｄ、２３ｂと逃げ片２２ｃ、２３ｃを有する形状）に形成している。
【００５４】
これによれば、締結部材１９、２０の装着作業に際して、締結部材１９、２０の装着方向性がなくなるので、その両端の引っ掛け部２２、２３のいずれを先にサイドプレート８ａ、８ｂに係止してもよい。
（第３実施形態）
図７は第３実施形態であり、第１、第２実施形態では、幅の狭い細長本体部２１と幅の広い両端の引っ掛け部２２、２３との間は、幅寸法が徐々に広がる円弧状（Ｒ形状）またはテーパ状の接続部２５によって接続しているが、第３実施形態ではこの接続部２５を廃止して、細長本体部２１と両端の引っ掛け部２２、２３とを段違い状に直接接続している。従って、接続部２５を廃止した分だけ、幅の狭い細長本体部２１の部分を長くすることができる。
【００５５】
（第４実施形態）
図８は第４実施形態であり、細長本体部２１の幅寸法を両端の引っ掛け部２２、２３の幅寸法と同一寸法まで拡大し、その代わりに、細長本体部２１の部分に長孔状の空気孔２９を設けて、コア面での通風抵抗を低減するようにしたものである。なお、空通過孔２９を１つの長孔とせずに、複数に分割した長孔にしてもよいことはもちろんである。
【００５６】
（第５実施形態）
図９は第５実施形態であり、細長本体部２１に１個または複数（図示の例では３個）の円弧状曲げ部３０を追加形成している。この円弧状曲げ部３０は細長本体部２１の途中部位をコア面から離れる方向に突出するように曲げ形成したものである。
【００５７】
この円弧状曲げ部３０が細長本体部２１の長手方向に弾性変形することにより、コア部３の寸法ばらつきの吸収効果を一層高めることができ、締結部材１９、２０の装着作業性をより改善できる。
（他の実施形態）
なお、上記の実施形態では、断面Ｕ字状の１枚の保持板１０の内側に電気発熱体９を挿入し、１枚の保持板１０の内側に電気発熱体９を圧接保持しているが、保持板１０を２枚の平板状の板に分離し、この２枚の平板状の保持板１０の間に電気発熱体９を圧接保持するようにしてもよい。
【００５８】
また、上記の実施形態では、車両暖房用熱交換器について説明したが、本発明は車両用に限定されることなく、種々な用途の暖房用熱交換器に広く適用可能である。
また、電気発熱体９の設置形態を図１の形態に限らず、暖房用熱交換器の仕様の変化に対応して種々変更し得ることはもちろんである。
【図面の簡単な説明】
【図１】本発明の第１実施形態を示す暖房用熱交換器の斜視図である。
【図２】図１の電気発熱体設置部の破断拡大斜視図である。
【図３】（ａ）は第１実施形態による締結部材の平面図、（ｂ）は同締結部材の正面図、（ｃ）は同締結部材の側面図である。
【図４】図１のサイドプレートの斜視図である。
【図５】図１に示すサイドプレートと締結部材の両端の引っ掛け部との係止部の拡大図である。
【図６】（ａ）は第２実施形態による締結部材の平面図、（ｂ）は同締結部材の正面図、（ｃ）は同締結部材の側面図である。
【図７】（ａ）は第３実施形態による締結部材の平面図、（ｂ）は同締結部材の正面図、（ｃ）は同締結部材の側面図である。
【図８】（ａ）は第４実施形態による締結部材の平面図、（ｂ）は同締結部材の正面図、（ｃ）は同締結部材の側面図である。
【図９】（ａ）は第９実施形態による締結部材の正面図、（ｂ）は同締結部材の側面図である。
【符号の説明】
１、２…タンク、３…熱交換用コア部、６…偏平チューブ、
７…コルゲートフィン、８ａ、８ｂ…サイドプレート、９…電気発熱体、
１０…保持板、１９、２０…締結部材、２１…細長本体部、
２２、２３…両端の引っ掛け部。[0001]
BACKGROUND OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating heat exchanger integrated with an electric heating element, and is a vehicle heating heat exchanger that heats air using hot water (engine cooling water) heated by a vehicle engine (internal combustion engine) as a heat source. It is suitable for use.
[0002]
[Prior art]
Conventionally, a heat exchanger in which this kind of electric heating element is integrated has been proposed in Japanese Patent Laid-Open No. 5-69732. According to this conventional apparatus, an electric heating element is integrated with a heating heat exchanger that heats air using hot water (engine cooling water) as a heat source, so that when the hot water temperature is low, such as immediately after the engine is started, By energizing the body, the heat generated by the electric heating element can be dissipated into the air to heat the air.
[0003]
[Problems to be solved by the invention]
By the way, in the conventional apparatus described in the above publication, the electric heating element composed of the heating element and the electrode plate is brazed integrally with the core of the heat exchanger for heating, so that a high brazing temperature (aluminum brazing temperature). In the case of attachment, since the heating element is exposed to an atmosphere of about 600 ° C., there is a problem that the electrical characteristics of the heating element are significantly impaired.
[0004]
Therefore, in the present applicant, in the heat exchanger for heating in which an electric heating element is installed in a part of the heat exchange core part composed of a combination of a flat tube and a corrugated fin, The holding plate is disposed between the bent corrugated fins of adjacent corrugated fins. The holding plate has a U-shaped cross section extending in the longitudinal direction of the flat tube, and the U-shaped holding plate is opposed to the holding plate. In a state where a predetermined interval is set between the two plate surfaces, the two plate surfaces are joined to the folded top portions of the corrugated fins, respectively, and the electric heating element is electrically insulated from the opening portion of the holding plate to the inside of the holding plate. Have already filed an application for a heat exchanger for heating (Japanese Patent Application No. 9-215042, etc.).
[0005]
In this prior application, since the electric heating element can be inserted and assembled into the holding plate after the brazing of the heating heat exchanger, the electrical characteristics of the electric heating element as disclosed in JP-A-5-69732 are disclosed. There is no worry about damage.
In the prior application, a cross-section of the electric heating element is obtained by attaching a fastening member (band member) that applies a tightening force to the heat exchanging core and holding the electric heating element in pressure contact within the holding plate. It can be securely held inside the U-shaped holding plate.
[0006]
Here, in the prior application, the fastening members are hooked at both ends of a long shape (elongated band shape) extending in a direction orthogonal to the longitudinal direction of the flat tube (in other words, the laminating direction of the flat tube and the corrugated fin). It is configured so that the hooks at both ends are hooked on the side plates on both sides of the heat exchanging core, but only by forming a fastening member in such a simple long shape (elongated band shape) In some cases, the fastening member may hinder ventilation to the heat exchanging core, or a problem such as deformation of the side plate may occur due to a pressing load from the fastening member.
[0007]
In view of the above, the present invention suppresses the occurrence of problems associated with mounting of a fastening member in a heating heat exchanger that uses a fastening member that exerts a tightening force to press-hold the electric heating element inside the holding plate. For the purpose.
[0008]
[Means for Solving the Problems]
  In order to achieve the above object, the invention according to claim 1 provides:A heat exchanging core (3) composed of a tube (6) through which a heat source fluid flows and a fin member (7) joined to the tube (6);
  A holding plate (10) disposed in a part of the heat exchanging core (3);,
  An electric heating element (9) disposed inside the holding plate (10);
  The heat exchanging core (3) is provided with fastening members (19, 20) for applying a tightening force so as to press and hold the electric heating element (9) inside the holding plate (10),
  The tube is a flat tube (6), the fin member is a corrugated fin (7),
  The holding plate is a holding plate (10) having a U-shaped cross section that is disposed between the folded top portions of adjacent corrugated fins (7) and extends in the longitudinal direction of the flat tube (6).
  The fastening members (19, 20) are positioned between the hooks (22, 23) at both ends locked to the ends of the heat exchanging core (3) and the hooks (22, 23) at both ends. And forming an elongated main body (21) facing the air passage surface of the heat exchanging core (3),
  The width of the elongated main body (21) is narrower than the width of the hooks (22, 23) at both ends.
[0009]
  According to this, since the width of the elongated main body portion (21) is narrower than the width of the hook portions (22, 23) at both ends, an increase in the ventilation resistance of the heat exchange core portion (3) accompanying the fastening member mounting is increased. Can be reduced. In addition, by increasing the width of the hooks (22, 23) at both ends, the pressure receiving area of the pressing load at the end of the heat exchange core (3) is expanded, and the heat exchange core (3) The deformation of the end can be suppressed.
  As in the invention described in claim 2, in the heat exchanger for heating according to claim 1, specifically, the holding plate (10) having a U-shaped cross section is provided, and the closed end (10a) is an air inlet. The fastening members (19, 20) may be disposed only on the surface of the heat exchanging core (3) on the air outlet side, with the opening (10b) facing toward the air outlet.
[0010]
  Claims3In the described invention, the end portion of the heat exchanging core portion (3) is applied to the fastening members (19, 20) for applying a tightening force so as to press and hold the electric heating element (9) inside the holding plate (10). Hooks (22, 23) at both ends locked to the two, and an elongate main body located between the hooks (22, 23) at both ends and facing the air passage surface of the heat exchanging core (3) (21) and an air passage hole (29) is formed in the elongated main body (21).
[0011]
According to this, since air can pass through the air passage hole (29) opened in the elongated main body (21), heat exchange associated with mounting of the fastening member can be achieved without specially reducing the width of the elongated main body (21). The increase in ventilation resistance of the core part (3) can be reduced. Moreover, since the hooks (22, 23) at both ends can be formed wide like the first aspect, the pressure receiving area of the pressing load at the end of the heat exchanging core (3) can be expanded to be used for heat exchanging. Deformation of the end of the core (3) can be suppressed.
[0012]
  Claim4Invention described inThen, the heat exchange core portion (3) composed of the tube (6) through which the heat source fluid flows and the fin member (7) joined to the tube (6),
A holding plate (10) disposed in a portion of the heat exchange core (3);
An electric heating element (9) disposed inside the holding plate (10);
The heat exchanging core (3) is provided with fastening members (19, 20) for applying a tightening force so as to press and hold the electric heating element (9) inside the holding plate (10),
Between the fastening members (19, 20), the hooks (22, 23) at both ends locked to the ends of the heat exchanging core (3) and the hooks (22, 23) at both ends An elongated main body (21) positioned and facing the air passage surface of the heat exchanging core (3),
The width of the elongated main body (21) is narrower than the width of the hooks (22, 23) at both ends,
  further,A bent portion (30) that can be elastically deformed in the longitudinal direction of the elongated body portion (21) is formed in the middle of the elongated body portion (21).It is characterized by that.
  according to this,The elastic deformation of the bent portion (30) absorbs the dimensional variation of the heat exchanging core portion (3), thereby facilitating the fastening member mounting operation.
  Claim5In the invention described in (1), the heat exchanging core (3) includes side plates (8a, 8b) disposed on both sides in the stacking direction of the tubes (6),
  The side plates (8a, 8b) include a plurality of convex ribs (26a, 26b) extending in the longitudinal direction and a concave groove (27) formed between the plurality of convex ribs (26a, 26b). It has an uneven shape,
  It is characterized in that the hooks (22, 23) at both ends are locked in the concave groove (27).
[0013]
  According to this, the hook portions (22, 23) at both ends can be easily and reliably locked using the concave and convex grooves (27) formed to increase the strength of the side plates (8a, 8b) themselves.
  Claim6In the invention described in item 1, the pressing load of the hooks (22, 23) at both ends is applied to the flat tops of the convex ribs (26a, 26b).
[0014]
  According to this, since the shape of the convex rib (26a, 26b) having a flat top portion can constitute a portion having high rigidity with respect to the pressing load from the hooking portions (22, 23), the side plate ( It is possible to satisfactorily suppress the deformation of 8a and 8b).
  Claim7In the invention described in (2), bent portions (22a, 23a) bent in a direction away from the surfaces of the side plates (8a, 8b) are formed in the hook portions (22, 23) at both ends.
[0015]
  According to this, since the bent portions (22a, 23a) are separated from the surfaces of the side plates (8a, 8b), it becomes possible to elastically deform the bent portions (22a, 23a) during the mounting work of the fastening member, It is possible to absorb the dimensional variation of the heat exchanging core (3) and facilitate the fastening member mounting operation.
  Claim8In the invention described in (1), a locking piece (22b) facing the inner side of the fastening member (19, 20) is formed on one of the hooks (22, 23) at both ends. The other hooking portion (23) includes a locking portion (23b) facing inward of the fastening member (19, 20), and a fastening member (19, 20) from the tip of the locking portion (23b). ) And a relief piece (23c) facing outward.
[0016]
According to this, at the time of mounting operation of the fastening member, after the engaging piece (22b) of one hooking part (22) is fitted into the locking part on the heat exchanging core part (3) side, the other hooking part ( 23) When the engaging portion (23b) of 23) is fitted into the engaging portion on the heat exchanging core portion (3) side, the escape piece (23c) facing outward at the distal end portion of the engaging portion (23b) Therefore, the escape piece (23c) is not caught by the engaging part on the heat exchanging core part (3) side, and the engaging part (23b) is attached to the heat exchanging core part (3) side. It can be easily fitted into the locking portion.
[0018]
In addition, the code | symbol in the bracket | parenthesis of each said means shows a corresponding relationship with the specific means of embodiment description later mentioned.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 shows the overall structure of a vehicle heating heat exchanger according to the first embodiment of the present invention. In FIG. 1, a heating heat exchanger H includes a hot water inlet side tank 1 and a hot water outlet side tank 2. And a heat exchanging core 3 provided between the tanks 1 and 2.
[0020]
The warm water inlet side tank 1 is provided with an inlet pipe 4 into which warm water (engine cooling water) from a vehicle engine (not shown) flows, and the warm water outlet side tank 2 is an outlet pipe that causes the warm water to flow outside and return to the engine side. 5 is provided. In addition, since the heat exchanger of this example is a right-and-left symmetrical form as shown in FIG. 1, you may reverse the hot water inlet side tank 1 and the hot water outlet side tank 2 right and left.
[0021]
Each of the tanks 1 and 2 includes a tank body 1a and 2a, and sheet metals 1b and 2b for closing the opening end faces of the tank body 1a and 2a, and a well-known tank structure in which the vertical direction in FIG. It is. A large number of flat tube insertion holes (not shown) are formed in the sheet metal 1b, 2b, and one or more rows are formed in the vertical direction of FIG.
[0022]
The heat exchanging core section 3 has a number of flat tubes 6 formed in a flat shape parallel to the flow direction of the heating air (in the direction of arrow A in FIG. 1) and arranged in parallel in the vertical direction in FIG. Then, corrugated fins (fin members) 7 formed in a wave shape are arranged and joined between the multiple flat tubes 6.
Openings at both ends of the flat tube 6 are inserted into and joined to the tube insertion holes of the sheet metals 1b and 2b, respectively. Further, side plates 8a and 8b are disposed on the outer side of the corrugated fins 7 on the outermost side (upper and lower end portions in FIG. 1) of the core part 3, and these side plates 8a and 8b are arranged on the outermost corrugated fins 7 and the sheet. Joined to the metal 1b, 2b.
[0023]
Furthermore, instead of the flat tube 6, an electric heating element 9 is installed in a part of the heat exchanging core 3. In the example of FIG. 1, electric heating elements 9 are installed at three equal intervals (shaded portions) of the heat exchanging core 3.
And in the site | part in which the electric heating element 9 is installed among the core parts 3 for heat exchange, it is the cross section U extended in the longitudinal direction of the flat tube 6 between the bending top parts of the adjacent corrugated fin 7 as shown in FIG. A character-shaped holding plate 10 is arranged. The closed end portion 10 a made of a U-shaped bent shape of the holding plate 10 faces the air inlet side of the heat exchange core portion 3, and the opening portion 10 b on the other end side faces the air outlet side of the heat exchange core portion 3. As described above, the arrangement direction of the holding plate 10 is set.
[0024]
In addition, the holding plate 10 sets a predetermined interval between the two opposing plate surfaces 10c and 10d, and in this state, the two plate surfaces 10c and 10d are respectively joined to the bent top portions of the corrugated fins 7. It is like that. The electric heating element 9 is inserted and held in the holding plate 10 through the opening 10b. Here, the electric heating element 9 is held electrically insulated from the holding plate 10 by a structure described later.
[0025]
Since the entire thickness of the holding plate 10 is set to be equal to the thickness of the flat tube 6, the holding plate 10 can be installed between adjacent corrugated fins 7 instead of the flat tube 6.
By the way, in the heat exchanger in this example, all of the components 1 to 8b are formed of aluminum (including aluminum alloy), and the holding plate 10 having a U-shaped cross section is also made of aluminum. Molded. The holding plate 10 is a thin metal plate having a thickness of about 0.1 to 0.5 mm, and the width of the flat holding plate 10 (the width in the flow direction A of the heating air) is substantially the same as the core thickness. Moreover, the dimension in the longitudinal direction of the holding plate 10 (the dimension in the left-right direction in FIG. 1) is substantially the same as the dimension between the sheet metals 1b and 2b.
[0026]
Next, the specific structure of the electric heating element 9 will be described with reference to FIG. 2. A plate-shaped heating element 9a and elongated flat plate-like electrode plates 9b, 9c arranged on both the front and back surfaces of the heating element 9a; It has a three-layer sandwich structure. The periphery of the electrode plates 9b and 9c is covered with a covering member 9d made of an electrically insulating material over the entire circumference. Here, the heating element 9a is a PTC heater element made of a resistor material (for example, barium titanate) having a positive resistance temperature characteristic in which the resistance value rapidly increases at a predetermined set temperature (for example, around 200 ° C.). is there.
[0027]
Both electrode plates 9b, 9c of the heating element 9a are metal thin plates formed from a conductive metal material such as aluminum, copper, stainless steel, etc., and the longitudinal dimensions of both the electrode plates 9b, 9c (the horizontal direction in FIG. 1). The dimension) is substantially the same as that of the holding plate 10. And the heat generating element 9a is arrange | positioned in multiple places in the longitudinal direction of both these electrode plates 9b and 9c. The heating element 9a and the two electrode plates 9b and 9c are brought into pressure contact with each other to obtain electrical continuity between them.
[0028]
The electric heating element 9 is assembled inside the holding plate 10 so that the covering member 9d is in pressure contact with the inner side surfaces of the plate surfaces 10c and 10d of the holding plate 10. Here, the covering member 9d serves to electrically insulate between the holding plate 10 and the two electrode plates 9b and 9c, but serves to conduct heat of the heating element 9a to the holding plate 10. The thickness of the covering member 9d between the holding plate 10 and the two electrode plates 9b and 9c is a thin film of about 25 μm to 100 μm to ensure a good heat conduction effect. As a specific material of the covering member 9d, a highly heat-resistant resin (for example, a polyimide resin) is preferable.
[0029]
The electrode plate 9b is, for example, a positive electrode plate, and the electrode plate 9c is, for example, a negative electrode plate. Each of the terminal portions for electrical connection is located near the left end of FIG. It is integrally molded. In this example, both the terminal portions protrude to the rear side (downstream side in the air flow direction A) of the heat exchanging core portion 3.
Next, the outline of the electrical connection structure of the electric heating element 9 will be described with reference to FIG. 1. Of the hot water inlet side tank 1 and the hot water outlet side tank 2, an electrical wiring cover 11 is provided on the hot water outlet side tank 2 in this example. It is installed. The electric wiring cover 11 is formed into a shape along the outer shape of the tank 2 with a resin (electrical insulating material) having a certain degree of elasticity such as polypropylene, and an integrally formed elastic locking claw piece (not shown). ) And is detachably mounted on the tank 2.
[0030]
Further, the electrical wiring cover 11 holds a positive lead wire 13 having a positive connector 12 and a negative lead wire 15 having a negative connector 14. Three positive electrode side lead wires 13 and one negative electrode side lead wire 15 are provided corresponding to the number of electric heating elements 9 (three).
The electrical wiring cover 11 has three locations protruding from the rear side (downstream side in the air flow direction A) of the heat exchange core 3 and the left end of FIG. Electrical connections 16, 17, 18 are provided. In these three electrical connection portions 16, 17, and 18, the connection terminal pieces electrically connected to the tip portions of the positive lead wire 13 and the negative lead wire 15 and the electrode plate 9b of the three electrical heating elements 9 are connected. , 9c are electrically connected.
[0031]
Note that an external control circuit (not shown) is electrically connected to the positive connector 12 and the negative connector 14, and each electric heating element 9 is energized from an in-vehicle power source via the external control circuit. .
Reference numerals 19 and 20 denote fastening (band) members made of a metal material having a spring property, which are arranged on the surface of the heat exchanging core 3 on the air outlet side. The fastening members 19 and 20 have hooking portions 22 and 23 having bent shapes at both ends thereof, and the fastening members 19 and 20 are hooked on the upper and lower side plates 8a and 8b. 20 is mounted between the upper and lower side plates 8a, 8b.
[0032]
By mounting the fastening members 19 and 20, a tightening force that presses and holds the electric heating element 9 between the plate surfaces 10 c and 10 d of the holding plate 10 can be applied to the heat exchanging core portion 3. In FIG. 1, the fastening members 19 and 20 are attached to two locations in the width direction of the core portion 3 (left and right direction in FIG. 1). Only one central portion in the width direction may be provided, or three or more may be provided.
[0033]
In this embodiment, since the holding plate 10 is formed in a U-shaped bent shape having the closed end portion 10a, the fastening member 12 is attached only to the opening 10b side (downstream side in the air flow direction A) of the holding plate 10. The electric heating element 9 can be held and fixed simply by mounting.
Next, the manufacturing method of the above-described heating heat exchanger H will be described. First, a core assembling step for assembling the heat exchanger configuration shown in FIG. 1 is first performed. That is, the tubes 6 and the corrugated fins 7 of the heat exchanging core portion 3 are alternately laminated, and portions of the heat exchanging core portion 3 where the electric heating elements 9 are installed (three hatched portions in FIG. 1). Then, the holding plate 10 having a U-shaped cross section extending in the longitudinal direction of the tube 6 is disposed between the folded top portions of the adjacent corrugated fins 7. Here, in order to hold the interval between the two opposing plate surfaces 10c, 10d of the holding plate 10 at a predetermined interval, a dummy plate (not shown) having a plate thickness at the predetermined interval is provided inside the holding plate 10. Insert).
[0034]
This dummy plate is formed of a material (for example, carbon) having heat resistance against the below-described integral brazing process and having a characteristic that aluminum brazing is not performed. Of course, tanks 1 and 2, pipes 4 and 5, and side plates 8a and 8b are also assembled in this assembling step.
Next, as described above, the assembled state of the assembled heat exchanger is held by an appropriate jig (not shown), and is carried into a brazing furnace to perform a brazing process. That is, the heat exchanger assembly is heated to a brazing temperature (about 600 ° C.) in a brazing furnace, and the aluminum clad brazing material of each heat exchanger member is melted to form a heat exchanger assembly. These members are integrally brazed.
[0035]
After the brazing is completed, the heat exchanger assembly is taken out of the brazing furnace, and after the temperature of the heat exchanger assembly is lowered to room temperature, the assembly process of the electric heating element 9 is performed. That is, the electric heating element 9 alone is independent of the heat exchanger assembly, and the front and back surfaces of the plate-like heating element 9a are sandwiched between the plate-like electrode plates 9b and 9c to form a three-layer sandwich structure. The periphery of the electrode plates 9b and 9c is covered with the covering member 9d over the entire circumference.
[0036]
Then, the dummy plates inserted inside the three holding plates 10 in the heat exchange core portion 3 of the heat exchanger assembly are taken out. Thereafter, the electric heating element 9 is inserted from the opening 10b toward the closed end 10a into a space at a predetermined interval formed inside the two opposing plate surfaces 10c and 10d of the holding plate 10. At this time, the electric heating element 9 is assembled in the holding plate 10 so that the covering member 9d is in pressure contact with the holding plate 10.
[0037]
After the electric heating element 9 is assembled, the hooks at both ends of the fastening members 19 and 20 are hooked on the upper and lower side plates 8a and 8b, and the fastening members 19 and 20 are placed between the upper and lower side plates 8a and 8b. Is mounted so that the core part 3 for heat exchange is compressed.
As a result, a clamping force that presses and holds the electric heating element 9 inside the holding plate 10 is applied to the heat exchanging core 3, and the electric heating element 9 can be reliably held and fixed inside the holding plate 10. At the same time, both the front and back surfaces of the heating element 9a are surely pressed into contact with the plate-like electrode plates 9b and 9c inside the electric heating element 9, so that a good electrical conduction state can be obtained with a small contact resistance.
[0038]
Next, the operation in the above configuration will be described. When heating the passenger compartment, an air-conditioning blower fan (not shown) is activated to heat the space between the flat tube 6 and the corrugated fin 7 of the core portion 3 of the heating heat exchanger H as indicated by an arrow A. Air passes through. On the other hand, warm water (heat source fluid) from the engine flows into the hot water inlet side tank 1 from the inlet pipe 4 by operation of a water pump (not shown) of the vehicle engine.
[0039]
The hot water is distributed to a large number of flat tubes 6 in the inlet side tank 1, and radiates heat to the heating air through the corrugated fins 7 while flowing in the flat tubes 6 in parallel. The hot water that has passed through a number of flat tubes 6 flows into the hot water outlet side tank 2 and is gathered here, and the hot water flows out of the heat exchanger from the outlet pipe 5 and returns to the engine side.
[0040]
On the other hand, when the temperature of hot water from the engine is lower than a set temperature (for example, 80 ° C.) during heating, both of the electric heating elements 9 are connected from the external control circuit via the connectors 12 and 14 and the lead wires 13 and 15. The voltage of the in-vehicle power source is applied between the electrode plates 9b and 9c. As a result, the heating element 9a is energized to generate heat. Heat generated by the heating element 9a is conducted to the corrugated fins 7 on both sides through the electrode plates 9b and 9c, the covering member 9d, and the holding plate 10, and is radiated from the corrugated fins 7 to the heating air. Accordingly, even when the hot water is at a low temperature, the heating air can be quickly heated to perform immediate heating.
[0041]
Since the heating element 9a of the electric heating element 9 is a PTC element having a positive resistance temperature characteristic in which the resistance value rapidly increases at a predetermined set temperature, the heating temperature is self-controlled to the set temperature as is well known. It has a self-temperature control function.
The overall configuration and operation of the heating heat exchanger H have been described above. Next, the specific shapes and mounting structures of the fastening members 19 and 20 that characterize the present invention will be described in detail. FIG. 3 shows the fastening members 19 and 20 according to the first embodiment. The fastening members 19 and 20 are formed by pressing a spring steel into a thin plate having a thickness t of about 1 mm in order to have a spring property. is there.
[0042]
Here, the fastening members 19 and 20 are composed of an elongated main body portion 21 that faces the heat exchanging core portion 3 and hook portions 22 and 23 at both ends. The hooks 22 and 23 at both ends have a width dimension W.₁= For example, the width is widened to about 10 mm.₂= For example, about 4 mm, and the width dimension W of the hooks 22 and 23₁The width is narrowed to ½ or less.
[0043]
The hook portions 22 and 23 at both ends have arc-shaped bent portions 22a and 23a that are directed inward (acute angle direction) from the elongated main body portion 21, respectively, and further, the distal end portion of one hook portion 22 Is formed with a locking piece 22b that is further bent inwardly of the fastening members 19 and 20.
In addition, an arcuate locking portion 23b that protrudes further inwardly of the fastening members 19 and 20 is formed at the distal end portion of the other hooking portion 23, and further, the fastening member 19 extends from the distal end portion of the arcuate locking portion 23b. , 20 flank 23c directed outward.
[0044]
In addition, the hole 24 opened at one place in the middle of the elongated main body 21 is a locking hole for the fastening member transfer hanger in the plating process, and the surface of the fastening members 19 and 20 is provided for improving rust prevention and corrosion resistance. The surface treatment layer (plating layer) is applied. Further, the narrow elongated main body portion 21 and the hook portions 22 and 23 at both ends having a wide width are connected by an arc-shaped (R-shaped) connecting portion 25 in which the width dimension gradually increases. Needless to say, the connecting portion 25 may have a linear taper shape instead of an arc shape (R shape).
[0045]
Next, FIG. 4 illustrates the shape of the side plates 8a and 8b for locking the fastening members 19 and 20, and the lower side of FIG. 4 is a surface facing the heat exchanging core 3 and the side plate 8a. , 8b is formed with a concavo-convex rib shape extending in the longitudinal direction, and the rib shape increases the section modulus to increase the rigidity. In the side plates 8a and 8b, a concave groove 27 is formed between two parallel convex ribs 26a and 26b extending in the longitudinal direction (central portion in the width direction).
[0046]
The fastening members 19 and 20 are attached to the side plates 8a and 8b using the uneven rib shape of the side plates 8a and 8b. That is, when the fastening members 19 and 20 are mounted, the locking piece 22b at one end of the fastening members 19 and 20 is either one of the upper and lower side plates 8a and 8b as shown in FIG. Fit into the concave groove 27 of the side plate and lock.
[0047]
Thereafter, the operator holds the elongate main body 21 in hand and applies a pressing force to elastically deform the end portions of the fastening members 19 and 20 on the side of the escape piece 23c, and the arcuate engagement adjacent to the escape piece 23c. The portion 23b is fitted into the concave groove 27 of the other side plate and locked.
With the above operation, the fastening members 19 and 20 can be easily attached to the side plates 8a and 8b using the concave grooves 27 of the side plates 8a and 8b. Here, in the hook portions 22 and 23 at both ends of the fastening members 19 and 20, the portions of the bent portions 22a and 23a are separated from the side end portions 28 of the side plates 8a and 8b by a predetermined amount as shown in an enlarged view in FIG. Since the spring part is easily elastically deformed, the dimensional variation of the core part 3 is absorbed by the elastic deformation of the bent parts 22a and 23a, and the workability when the fastening members 19 and 20 are attached can be improved.
[0048]
Further, out of the hook portions 22 and 23 at both ends of the fastening members 19 and 20, the hook portions 23 on the side to be fitted later are provided with escape pieces 23 c directed in the outward direction of the fastening members 19 and 20 in an arc shape. Since it is provided at the distal end side of the locking portion 23b, the escape piece 23c is not caught by the convex ribs 26a, 26b, and the fitting operation of the arc-shaped locking portion 23b can be easily performed, and the fastening member 19, 20 can be further facilitated.
[0049]
When the fastening members 19 and 20 are mounted between the upper and lower side plates 8a and 8b, the hook portions 22 and 23 at both ends of the fastening members 19 and 20 are not mounted as shown in FIG. It elastically deforms from the solid line position to the two-dot chain line position after mounting, and the interval between the hook portions 22 and 23 at both ends is expanded. As a result, an elastic reaction force is generated between the hook portions 22 and 23 at both ends, and a tightening force in the compression direction can be applied to the heat exchanging core portion 3.
[0050]
In addition, among the fastening members 19 and 20, the width of the elongated main body portion 21 facing the air passage surface of the core portion 3 is made narrower than the hook portions 22 and 23 at both ends, thereby allowing ventilation on the air passage surface of the core portion 3. Increase in resistance can be minimized.
Furthermore, according to the present embodiment, there are the following advantages. That is, when developing the heat exchanger H for heating of the electric heating element integrated system, the inventors of the present invention initially set the hook portions 22 and 23 at both ends of the fastening members 19 and 20 to the side plates 8a and 8b. In this case, the tightening force by the fastening members 19 and 20 is concentrated on the side end portion 28, the deformation of the side plates 8a and 8b, There was a problem that the corrugated fins 7 joined to the deformed portions of the side plates 8a and 8b caused buckling.
[0051]
However, according to the present embodiment, the widths of the hook portions 22 and 23 at both ends of the fastening members 19 and 20 are wider than the elongated main body portion 21 (more than doubled), and stress concentration on the side plates 8a and 8b is reduced. 5, the engaging position between the hook portions 22 and 23 and the side plates 8 a and 8 b is changed to the concave groove 27 instead of the side end portion 28, and the pressing load of the fastening members 19 and 20 is changed to an arrow B in FIG. 5. As shown, it is added to the flat top of the convex rib 26a.
[0052]
Since the shape of the convex rib 26a having the flat top portion can constitute a portion having high rigidity (a portion having a large section modulus) with respect to the pressing load from the hooking portions 22 and 23, the side plates 8a and 8b can be formed by this pressing load. Can be satisfactorily suppressed from deforming. Therefore, buckling of the corrugated fin 7 due to deformation of the side plates 8a and 8b can be prevented.
[0053]
(Second Embodiment)
FIG. 6 shows the second embodiment. In the first embodiment, the hooks 22 and 23 at both ends of the fastening members 19 and 20 are formed in different shapes, that is, the locking piece 22b is formed on one hook 22 side. In the second embodiment, the arcuate locking portion 23b and the escape piece 23c are formed. However, in the second embodiment, as shown in FIG. (Both are shapes having arcuate locking portions 22d and 23b and relief pieces 22c and 23c having the same shape).
[0054]
According to this, since the mounting directionality of the fastening members 19 and 20 is lost when the fastening members 19 and 20 are attached, either of the hook portions 22 and 23 at both ends thereof is first locked to the side plates 8a and 8b. May be.
(Third embodiment)
FIG. 7 shows a third embodiment. In the first and second embodiments, an arc shape in which the width dimension gradually increases between the narrow elongated main body portion 21 and the wide hook portions 22 and 23 at both ends. In the third embodiment, the connection portion 25 is eliminated, and the elongated main body portion 21 and the hook portions 22 and 23 at both ends are directly stepped. Connected. Therefore, the portion of the narrow main body portion 21 having a narrow width can be lengthened by the amount that the connection portion 25 is eliminated.
[0055]
(Fourth embodiment)
FIG. 8 shows a fourth embodiment in which the width of the elongated body 21 is enlarged to the same dimension as the widths of the hooks 22 and 23 at both ends. Air holes 29 are provided to reduce the ventilation resistance on the core surface. Needless to say, the air passage hole 29 may be divided into a plurality of long holes instead of one long hole.
[0056]
(Fifth embodiment)
FIG. 9 shows a fifth embodiment in which one or more (three in the illustrated example) arcuate bent portions 30 are additionally formed in the elongated main body 21. The arc-shaped bent portion 30 is formed by bending an intermediate portion of the elongated main body portion 21 so as to protrude in a direction away from the core surface.
[0057]
The arc-shaped bent portion 30 is elastically deformed in the longitudinal direction of the elongated main body portion 21, whereby the effect of absorbing the dimensional variation of the core portion 3 can be further enhanced, and the mounting workability of the fastening members 19 and 20 can be further improved. .
(Other embodiments)
In the above embodiment, the electric heating element 9 is inserted inside the single holding plate 10 having a U-shaped cross section, and the electric heating element 9 is pressed and held inside the single holding plate 10. The holding plate 10 may be separated into two flat plates, and the electric heating element 9 may be held in pressure contact between the two flat holding plates 10.
[0058]
Moreover, although said embodiment demonstrated the heat exchanger for vehicle heating, this invention is not limited to vehicles, but is widely applicable to the heat exchanger for heating of various uses.
Moreover, the installation form of the electric heating element 9 is not limited to the form shown in FIG.
[Brief description of the drawings]
FIG. 1 is a perspective view of a heating heat exchanger showing a first embodiment of the present invention.
2 is a cutaway enlarged perspective view of the electric heating element installation portion of FIG. 1. FIG.
3A is a plan view of the fastening member according to the first embodiment, FIG. 3B is a front view of the fastening member, and FIG. 3C is a side view of the fastening member.
4 is a perspective view of the side plate of FIG. 1. FIG.
FIG. 5 is an enlarged view of a locking portion between the side plate shown in FIG. 1 and hook portions at both ends of the fastening member.
6A is a plan view of a fastening member according to a second embodiment, FIG. 6B is a front view of the fastening member, and FIG. 6C is a side view of the fastening member.
7A is a plan view of a fastening member according to a third embodiment, FIG. 7B is a front view of the fastening member, and FIG. 7C is a side view of the fastening member.
8A is a plan view of a fastening member according to a fourth embodiment, FIG. 8B is a front view of the fastening member, and FIG. 8C is a side view of the fastening member.
9A is a front view of a fastening member according to a ninth embodiment, and FIG. 9B is a side view of the fastening member.
[Explanation of symbols]
1, 2 ... tank, 3 ... heat exchange core, 6 ... flat tube,
7 ... corrugated fins, 8a, 8b ... side plates, 9 ... electric heating elements,
DESCRIPTION OF SYMBOLS 10 ... Holding plate, 19, 20 ... Fastening member, 21 ... Elongated main-body part,
22, 23 ... Hooks at both ends.

Claims

A heat exchanging core (3) composed of a tube (6) through which a heat source fluid flows and a fin member (7) joined to the tube (6);
A holding plate (10) disposed in a portion of the heat exchange core (3);
An electric heating element (9) disposed inside the holding plate (10);
Fastening members (19, 20) for applying a tightening force to the heat exchanging core (3) so as to press-hold the electric heating element (9) inside the holding plate (10),
The tube is a flat tube (6), the fin member is a corrugated fin (7),
The holding plate is a holding plate (10) having a U-shaped cross section that is disposed between the bent top portions of the adjacent corrugated fins (7) and extends in the longitudinal direction of the flat tube (6).
Between the fastening members (19, 20), the hooks (22, 23) at both ends locked to the ends of the heat exchange core (3), and the hooks (22, 23) at both ends An elongated main body (21) facing the air passage surface of the heat exchanging core (3),
A heating heat exchanger characterized in that the width of the elongated main body (21) is narrower than the width of the hooks (22, 23) at both ends.

The U-shaped holding plate (10) is arranged such that its closed end (10a) faces the air inlet side and its opening (10b) faces the air outlet side,
The heating heat exchanger according to claim 1, wherein the fastening members (19, 20) are arranged only on the air outlet side surface of the heat exchanging core (3).

A heat exchanging core (3) composed of a tube (6) through which a heat source fluid flows and a fin member (7) joined to the tube (6);
A holding plate (10) disposed in a portion of the heat exchange core (3);
An electric heating element (9) disposed inside the holding plate (10);
Fastening members (19, 20) for applying a tightening force to the heat exchanging core (3) so as to press-hold the electric heating element (9) inside the holding plate (10),
Between this fastening member (19, 20), the hook part (22, 23) of both ends latched by the edge part of the said heat exchange core part (3), and the hook part (22, 23) of this both ends An elongated main body (21) facing the air passage surface of the heat exchanging core (3),
A heat exchanger for heating, wherein an air passage hole (29) is opened in the elongated main body (21).

A heat exchanging core (3) composed of a tube (6) through which a heat source fluid flows and a fin member (7) joined to the tube (6);
A holding plate (10) disposed in a portion of the heat exchange core (3);
An electric heating element (9) disposed inside the holding plate (10);
Fastening members (19, 20) for applying a tightening force to the heat exchanging core (3) so as to press-hold the electric heating element (9) inside the holding plate (10),
Between this fastening member (19, 20), the hook part (22, 23) of both ends latched by the edge part of the said heat exchange core part (3), and the hook part (22, 23) of this both ends An elongated main body (21) facing the air passage surface of the heat exchanging core (3),
The width of the elongated main body (21) is narrower than the width of the hooks (22, 23) at both ends,
Furthermore, the heating heat exchanger characterized by the bending part (30) which can be elastically deformed in the longitudinal direction of the said elongate main-body part (21) formed in the middle of the said elongate main-body part (21) .

The heat exchange core (3) includes side plates (8a, 8b) disposed on both sides of the tube (6) in the stacking direction,
The side plates (8a, 8b) include a plurality of convex ribs (26a, 26b) extending in the longitudinal direction and a concave groove (27) formed between the plurality of convex ribs (26a, 26b). It has an uneven shape,
The heating heat exchanger according to any one of claims 1 to 4 , wherein the hooks (22, 23) at both ends are locked to the concave groove (27).

The heating heat exchanger according to claim 5 , wherein a pressing load of the hook portions (22, 23) at both ends is applied to the flat top portions of the convex ribs (26a, 26b).

Claim 5 or 6, characterized in that said side plates (8a, 8b) bent portion which is bent in a direction away from the surface of (22a, 23a) are formed on the hooked portion of said end (22, 23) Heat exchanger for heating described in 1.

Of the hooks (22, 23) at both ends, one hook (22) is formed with a locking piece (22b) facing the inside of the fastening member (19, 20), and the other hook The part (23) includes a locking part (23b) facing inward of the fastening member (19, 20), and the fastening member (19, 20) from the tip of the locking part (23b). The heat exchanger for heating according to any one of claims 1 to 7, wherein a relief piece (23c) facing outward is formed.