JP4100184B2

JP4100184B2 - Refrigeration cycle equipment

Info

Publication number: JP4100184B2
Application number: JP2003027049A
Authority: JP
Inventors: 悦久山田; 繁樹伊藤
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 2003-02-04
Filing date: 2003-02-04
Publication date: 2008-06-11
Anticipated expiration: 2023-02-04
Also published as: JP2004239469A

Description

【０００１】
【発明の属する技術分野】
本発明は、車両空調用等に好適な冷凍サイクル装置に関するものである。
【０００２】
【従来の技術】
本出願人は、先に、特許文献１にて従来のレシーバサイクルおよびアキュムレータサイクルとは異なる新規な方式により蒸発器出口ガス冷媒の過熱度を調整する冷凍サイクル装置を提案している。
【０００３】
この従来技術は、具体的には、図６に示す冷凍サイクル基本構成を有するものであり、凝縮器１５に第１、第２熱交換部１８ａ、１８ｂを設定するとともに、この第１、第２熱交換部１８ａ、１８ｂの間に気液分離器２を配置している。そして、圧縮機１の吐出ガス冷媒の主流を凝縮器１５の入口ジョイント４０から吐出ガス主通路４６を経て第１熱交換部１８ａに流入させる。
【０００４】
この第１熱交換部１８ａで凝縮した液冷媒の一部を液冷媒バイパス通路４１により気液分離器２内に流入させるとともに、圧縮機１の吐出ガス冷媒の一部を入口ジョイント４０の下流側から吐出ガスバイパス通路４２に分岐し、この吐出ガスバイパス通路４２を通過して吐出ガス冷媒の一部を気液分離器２内に流入させる。
【０００５】
気液分離器２内にて凝縮後の液冷媒と吐出ガス冷媒とが混合、熱交換するとともに、その混合冷媒の気液がガス冷媒と液冷媒の密度差により分離され、液冷媒は気液分離器２内の下部に溜まり、ガス冷媒は気液分離器２内の上部に溜まる。
【０００６】
第２熱交換部１８ｂは第１熱交換部１８ａの冷媒流れ下流側に接続されるものであって、第２熱交換部１８ｂの入口側には、第１熱交換部１８ａで凝縮した液冷媒の主流が流れる液冷媒導入通路４３が接続される。更に、気液分離器２のガス冷媒戻し通路４４および液冷媒戻し通路４５が第２熱交換部１８ｂの入口側に接続される。
【０００７】
従って、第１熱交換部１８ａで凝縮した液冷媒の主流、気液分離器２内上部のガス冷媒および気液分離器２内下部の液冷媒の三者が第２熱交換部１８ｂに流入し、これらの冷媒が第２熱交換部１８ｂで再度冷却され、過冷却状態となる。この過冷却液冷媒が減圧装置３５により減圧されて低圧の気液２相状態となり、この低圧冷媒が蒸発器３６にて蒸発した後に、圧縮機１に吸入される。
【０００８】
上記従来技術では、気液分離器２内にて凝縮後の液冷媒と吐出ガス冷媒とが混合、熱交換するので、この混合冷媒の乾き度が圧縮機吐出ガス冷媒の過熱度に応じて変化して、気液分離器２内に溜まる液冷媒量を圧縮機吐出ガス冷媒の過熱度に応じて調整することができる。従って、この気液分離器２内の液冷媒量の調整によりサイクル内循環冷媒流量を調整し、その結果、圧縮機の吐出ガス冷媒の過熱度、ひいては蒸発器出口ガス冷媒の過熱度を調整できる。
【０００９】
このように、上記従来技術によると、サイクル高圧側に設けた気液分離器２内の液冷媒量の調整により蒸発器出口ガス冷媒の過熱度を調整できるので、減圧装置３５として固定絞り、あるいは高圧冷媒の状態に応動する可変絞り等を使用できる。そのため、減圧装置３５として、構造が複雑で高価な温度式膨張弁を使用せずにすむという利点がある。また、気液分離器２を冷媒比体積の小さいサイクル高圧側に設けるから、気液分離器２を低圧側気液分離器（アキュムレータ）に比較して小型化できる等の利点も得られる。
【００１０】
【特許文献１】
特開２００２−３２３２７４号公報
【００１１】
【発明が解決しようとする課題】
ところで、上記従来技術においては、凝縮器１５に圧縮機１の吐出ガス冷媒が流入する冷媒入口ジョイント４０を配置し、この冷媒入口ジョイント４０から吐出ガス冷媒の主流を第１熱交換部１８ａに流入させる吐出ガス冷媒主通路４６、および冷媒入口ジョイント４０から吐出ガス冷媒の一部を気液分離器２内に直接流入させる吐出ガスバイパス通路４２を凝縮器１５に形成している。
【００１２】
従って、従来技術では、吐出ガス冷媒を第１熱交換部１８ａ側と気液分離器２側とに分配する冷媒通路構成を凝縮器１５側に設ける必要があるので、凝縮器１５の冷媒通路構成が複雑となり、製造コストが上昇するという問題がある。
【００１３】
また、サイクル内循環冷媒流量を圧縮機吐出ガス冷媒の過熱度に応じて所期の目標通りに調整するためには気液分離器２内へ流入する吐出ガス流入量を精度良く規定する必要があり、そのため、吐出ガスバイパス通路４２の通路面積を高精度に仕上げる必要がある。
【００１４】
しかし、実際には、凝縮器ろう付け時のろう材の回り込み等の影響で、吐出ガスバイパス通路４２の通路面積が所期の設計値からある程度変化することは不可避である。この吐出ガスバイパス通路４２の通路面積の変化により気液分離器２内への吐出ガス流入量が変化するので、サイクル内循環冷媒流量を圧縮機吐出ガス冷媒の過熱度に応じて適切に調整できない原因となる。
【００１５】
例えば、吐出ガスバイパス通路１０の通路面積がろう材の回り込み等により所期の設計値から減少すると、液冷媒流入量に対する吐出ガス流入量の割合が所期の設定割合から減少し、吐出ガス冷媒の過熱度変化を気液分離器２内に適切にフィードバックできない。その結果、吐出ガス冷媒の過熱度に対して気液分離器２内に溜まる液冷媒量が過度に増加し、サイクル内循環冷媒流量が吐出ガス冷媒の過熱度に対して過小となり、冷房性能の低下を起こす。
【００１６】
本発明は上記点に鑑みて、サイクル高圧側に設けられる気液分離器内に溜まる液冷媒量を調整して、サイクル内循環冷媒流量を調整する冷凍サイクル装置において、凝縮器の冷媒通路構成の簡素化を図ることを目的とする。
【００１７】
また、本発明は、サイクル高圧側に設けられる気液分離器内に溜まる液冷媒量を調整して、サイクル内循環冷媒流量を調整する冷凍サイクル装置において、吐出ガスバイパス通路の通路面積が凝縮器ろう付け時のろう材の回り込みにより変化することを防止することを他の目的とする。
【００１８】
【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に記載の発明では、圧縮機（１）の吐出ガス冷媒が放熱して凝縮する第１熱交換部（１８ａ）と、第１熱交換部（１８ａ）の冷媒流れ下流側に設けられる第２熱交換部（１８ｂ）と、圧縮機（１）の吐出ガス冷媒の一部および第１熱交換部（１８ａ）を通過した冷媒の少なくとも一部が流入し、流入冷媒の気液を分離して液冷媒を溜める気液分離器（２）と、気液分離器（２）内部のガス冷媒を第２熱交換部（１８ｂ）に導入するガス冷媒戻し通路（２３、２４、２５、２７、２８）とを備え、気液分離器（２）内に溜まる液冷媒量を圧縮機（１）の吐出ガス冷媒の過熱度に応じて調整する冷凍サイクル装置において、
気液分離器（２）は流入冷媒の気液分離空間（５）を形成するタンク本体（４）を有し、
圧縮機（１）の吐出ガス冷媒が流入する吐出ガス入口ジョイント（３）がタンク本体（４）に組み付けられ、
タンク本体（４）は、第１熱交換部（１８ａ）及び第２熱交換部（１８ｂ）を有する凝縮器（１５）と別体であって、凝縮器（１５）に締め付け固定されるようになっており、
タンク本体（４）の内部に、吐出ガス入口ジョイント（３）からの吐出ガス冷媒を２つの流れに分岐する分岐部と、分岐部からの一方の吐出ガス冷媒を第１熱交換部（１８ａ）の入口に流入させる凝縮用吐出ガス通路（１１）と、分岐部からの他方の吐出ガス冷媒を気液分離空間（５）に直接流入させる吐出ガスバイパス通路（８）とが形成されており、
また、第１熱交換部（１８ａ）を通過した冷媒の少なくとも一部を気液分離空間（５）に導入するための冷媒導入通路（１２）がタンク本体（４）に形成されており、
さらに、凝縮用吐出ガス通路（１１）と第１熱交換部（１８ａ）の入口側との間、および第１熱交換部（１８ａ）の出口側と冷媒導入通路（１２）との間をそれぞれＯリングシール部を備えた連結部により連結するとともに、ガス冷媒戻し通路（２３、２４、２５、２７、２８）の中間部もＯリングシール部を備えた連結部により連結することを特徴とする。
【００１９】
これによると、吐出ガス入口ジョイント（３）をタンク本体（４）に組み付け、このタンク本体（４）を凝縮器（１５）に締め付け固定し、吐出ガス入口ジョイント（３）からの吐出ガス冷媒の分岐部と、この分岐部で分岐された吐出ガス冷媒を第１熱交換部（１８ａ）側と気液分離空間（５）側に分配する通路部（８、１１）とをタンク本体（４）内に形成するから、このような吐出ガス分配通路部を、第１熱交換部（１８ａ）を含む凝縮器側に設ける必要がない。これにより、凝縮器の冷媒通路構成を簡素化して凝縮器の製造コストを低減できる。
【００２０】
しかも、凝縮用吐出ガス通路（１１、１１ａ）および吐出ガスバイパス通路（８）は、凝縮器の外部において凝縮器のろう付けと無関係に構成できるから、凝縮器のろう付け工程のろう材回り込みの影響を受けない。従って、吐出ガスバイパス通路（８）の通路面積として加工当初の寸法精度を維持できるので、吐出ガスバイパス通路（８）の通路面積の変化を抑えて、サイクル内循環冷媒流量を圧縮機吐出ガス冷媒の過熱度に応じて適切に調整できる。
【００２２】
また、請求項１に記載の発明では、タンク本体（４）の内部に、凝縮用吐出ガス通路（１１）と吐出ガスバイパス通路（８）とを形成しているので、凝縮用吐出ガス通路（１１）および吐出ガスバイパス通路（８）をタンク本体（４）に一体形成することができる。従って、下記の請求項２に比較して吐出ガス入口ジョイント（３）の形状を通常の汎用性のある簡単な形状にすることができる。
【００２３】
請求項２に記載の発明では、圧縮機（１）の吐出ガス冷媒が放熱して凝縮する第１熱交換部（１８ａ）と、第１熱交換部（１８ａ）の冷媒流れ下流側に設けられる第２熱交換部（１８ｂ）と、圧縮機（１）の吐出ガス冷媒の一部および第１熱交換部（１８ａ）を通過した冷媒の少なくとも一部が流入し、流入冷媒の気液を分離して液冷媒を溜める気液分離器（２）と、気液分離器（２）内部のガス冷媒を第２熱交換部（１８ｂ）に導入するガス冷媒戻し通路（２３、２４、２５、２７、２８）とを備え、気液分離器（２）内に溜まる液冷媒量を圧縮機（１）の吐出ガス冷媒の過熱度に応じて調整する冷凍サイクル装置において、
気液分離器（２）は流入冷媒の気液分離空間（５）を形成するタンク本体（４）を有し、
圧縮機（１）の吐出ガス冷媒が流入する吐出ガス入口ジョイント（３）がタンク本体（４）にＯリングシール部を備えた締め付け固定構造にて組み付けられ、
タンク本体（４）は、第１熱交換部（１８ａ）及び第２熱交換部（１８ｂ）を有する凝縮器（１５）と別体であって、凝縮器（１５）に締め付け固定されるようになっており、
吐出ガス入口ジョイント（３）の内部に、吐出ガス冷媒を２つの流れに分岐する分岐部と、分岐部からの一方の吐出ガス冷媒を第１熱交換部（１８ａ）の入口側に向かって流す凝縮用吐出ガス通路（１１ａ）と、分岐部からの他方の吐出ガス冷媒を気液分離空間（５）に直接流入させる吐出ガスバイパス通路（８）とが形成されており、
タンク本体（４）には、凝縮用吐出ガス通路（１１ａ）と第１熱交換部（１８ａ）の入口側とを連通させるタンク側凝縮用吐出ガス通路（１１）、および第１熱交換部（１８ａ）を通過した冷媒の少なくとも一部を気液分離空間（５）に導入するための冷媒導入通路（１２）が形成されており、
さらに、タンク側凝縮用吐出ガス通路（１１）と第１熱交換部（１８ａ）の入口側との間、および第１熱交換部（１８ａ）の出口側と冷媒導入通路（１２）との間をそれぞれＯリングシール部を備えた連結部により連結するとともに、ガス冷媒戻し通路（２３、２４、２５、２７、２８）の中間部もＯリングシール部を備えた連結部により連結することを特徴とする。
【００２４】
請求項２に記載の発明においても、上述した請求項１に記載の発明と同様の作用効果を発揮できる。特に、請求項２に記載の発明では、吐出ガス入口ジョイント（３）に凝縮用吐出ガス通路（１１ａ）および吐出ガスバイパス通路（８）を形成しているので、吐出ガス入口ジョイント（３）を変更するのみで、凝縮用吐出ガス通路（１１ａ）および吐出ガスバイパス通路（８）の仕様を変更することができる。従って、冷凍サイクルの仕様変更への対応を極めて簡単に行うことができる。
【００２５】
請求項３に記載の発明では、請求項１または２において、第１熱交換部（１８ａ）を通過した冷媒の全量を気液分離器（２）に流入させることを特徴とする。
【００２６】
これによると、第１熱交換部（１８ａ）を通過して凝縮した液冷媒の全量が気液分離器（２）内に流入するので、気液分離器（２）内への液冷媒導入量が前述の従来技術に比較して大幅に増加する。このため、気液分離器（２）内への吐出ガス冷媒分配量を前述の従来技術に比較して大幅に増加でき、これに伴って、、吐出ガスバイパス通路（８）の通路面積（通路径）を前述の従来技術における吐出ガスバイパス通路（４２）よりも大幅に大きくすることができる。
【００２７】
そのため、請求項３では、吐出ガスバイパス通路（８）の加工上の寸法バラツキの影響により上記通路面積が所期の設計値からある程度変化しても、この通路面積の所期の設計値に対する変化割合を十分小さくできる。
【００２８】
これにより、上記通路面積の変化に基づく吐出ガス冷媒分配量の変化割合を前述の従来技術よりも大幅に低減でき、この結果、気液分離器（２）内への吐出ガス流入量の変化割合を小さくして、サイクル内循環冷媒流量の調整作用に対する製造上の寸法バラツキの影響度合いを低減できる。
【００２９】
換言すると、吐出ガスバイパス通路（８）の寸法を高精度に仕上げる必要性が低下するので、吐出ガスバイパス通路（８）の加工コストを低減できる。
【００３０】
請求項４に記載の発明のように、請求項１または２において、第１熱交換部（１８ａ）を通過した冷媒の一部のみを気液分離器（２）に流入させ、第１熱交換部（１８ａ）を通過した冷媒の残部を第２熱交換部（１８ｂ）に流入させるようにしてもよい。
【００３１】
請求項５に記載の発明では、請求項１ないし４のいずれか１つにおいて、気液分離器（２）内に溜まる液冷媒の一部を取り出す液冷媒戻し通路（２９）を有し、液冷媒戻し通路（２９）をガス冷媒戻し通路（２３、２４、２５、２７、２８）に合流し、気液分離器（２）内のガス冷媒と液冷媒を合流した状態で、第２熱交換部（１８ｂ）に導入することを特徴とする。
【００３２】
これにより、気液分離器（２）内に溜まる液冷媒に含まれる潤滑オイルを常にサイクル循環冷媒中に還流できるので、圧縮機（１）の潤滑性を確実に確保できる。しかも、気液分離器（２）内のガス冷媒と液冷媒を合流して第２熱交換部（１８ｂ）に導入するから、液冷媒戻し通路（２９）を簡単に構成できる。
【００３３】
なお、上記各手段の括弧内の符号は、後述する実施形態に記載の具体的手段との対応関係を示すものである。
【００３４】
【発明の実施の形態】
（第１実施形態）
図１は第１実施形態による高圧側気液分離器と凝縮器の具体的構成および冷凍サイクル装置の基本構成を示す図であり、車両空調用冷凍サイクルに適用した場合を示している。図２は図１の要部拡大図である。
【００３５】
冷凍サイクル装置の圧縮機１は電磁クラッチ１ａを介して車両エンジン（図示せず）によりベルト駆動される。圧縮機１から吐出された高温高圧のガス冷媒はまず最初に高圧側の気液分離器２の冷媒入口ジョイント３に流入するようになっている。
【００３６】
ここで、気液分離器２はタンク本体４を有し、このタンク本体４はアルミニュウム等の金属により上下方向に延びる縦長の概略円筒状に形成され、冷媒の気液分離および液冷媒の貯留のための気液分離空間５を形成する。このタンク本体４の上面壁部には円形の上部開口部６が形成され、この上部開口部６内に冷媒入口ジョイント３の円筒状突出部３ａが嵌合される。円筒状突出部３ａに円周方向の外周溝部３ｂを形成して、この外周溝部３ｂに弾性シール材としてＯリング３ｃを装着し、このＯリング３ｃにより円筒状突出部３ａと上部開口部６の内周壁面との間のシールを保持する。
【００３７】
冷媒入口ジョイント３は図示しないボルトによりタンク本体４の上面壁部に締め付け固定される。冷媒入口ジョイント３は円筒状突出部３ａの軸方向（上下方向）に貫通する通路穴３ｄを有し、この通路穴３ｄを通過して圧縮機１の吐出ガス冷媒が上部開口部６の内側空間に流入する。
【００３８】
上部開口部６の上端面から所定寸法だけ下方の部位にリング状板部７が上部開口部６の内側空間の内方へ突き出すように形成され、このリング状板部７の中心部に微小穴を開けて吐出ガスバイパス通路８が形成されている。ここで、リング状板部７はダイキャスト加工等によりタンク本体４に一体成形できる。そして、リング状板部７の中心部に切削加工により微小穴を高精度で開けて、吐出ガスバイパス通路８を形成する。
【００３９】
この吐出ガスバイパス通路８は上部開口部６の内側空間に流入した吐出ガス冷媒の一部を分岐して気液分離空間５側へ直接流入（バイパス）させるものであって、吐出ガスバイパス通路８の通路面積（穴開口面積）により気液分離空間５側への吐出ガス冷媒流入量（バイパス量）を規定できる。
【００４０】
タンク本体４の上部側面壁部４ａのうち、吐出ガスバイパス通路８の上方側（上流側）部位および下方側（下流側）部位に、それぞれ後述する凝縮器１５の一方のヘッダタンク１９側へ突き出す円筒状突出部９、１０が一体に形成されている。この両円筒状突出部９、１０のうち上方側の円筒状突出部９の中心部に貫通穴を開けて凝縮用吐出ガス通路１１を形成する。
【００４１】
この凝縮用吐出ガス通路１１の通路面積と吐出ガスバイパス通路８の通路面積との比率により両通路８、１１への吐出ガスの分配割合を規定するようになっている。本実施形態では、凝縮用吐出ガス通路１１への吐出ガスの分配量よりも吐出ガスバイパス通路８の吐出ガスの分配量の方が多くなるようにしてある。
【００４２】
また、両円筒状突出部９、１０のうち下方側の円筒状突出部１０の中心部にも貫通穴を開けて液冷媒通路１２を形成する。この液冷媒通路１２は凝縮器１５の第１熱交換部１８ａにて凝縮した液冷媒の全量をタンク本体４内の空間５のうち吐出ガスバイパス通路８の直下の気液混合部１３に導入するものである。
【００４３】
両円筒状突出部９、１０にはそれぞれ円周方向の外周溝部９ａ、１０ａが形成され、この外周溝部９ａ、１０ａにそれぞれ弾性シール材としてＯリング９ｂ、１０ｂを装着している。
【００４４】
接続ジョイント１４はアルミニウムニュウム等の金属にて形成され、凝縮器１５の一方のヘッダタンク１９にろう付けにより接合される。この接続ジョイント１４にはタンク本体４の両円筒状突出部９、１０を嵌合するための円形の通路穴１４ａ、１４ｂが開けてある。この通路穴１４ａ、１４ｂの通路面積は凝縮用吐出ガス通路１１および液冷媒通路１２の通路面積より所定量大きくしてある。
【００４５】
接続ジョイント１４の通路穴１４ａ、１４ｂの内周壁面と両円筒状突出部９、１０との間をＯリング９ｂ、１０ｂによりシールするようになっている。タンク本体４は図示しないボルトにより接続ジョイント１４に締め付け固定されるようになっている。
【００４６】
接続ジョイント１４のうちヘッダタンク１９側の端面に通路穴１４ａ、１４ｂにそれぞれ対応して円形の嵌合突部１４ｃ、１４ｄが形成され、この嵌合突部１４ｃ、１４ｄをヘッダタンク１９の嵌合穴部（図示せず）に嵌合した状態で接続ジョイント１４はヘッダタンク１９にろう付けにより接合される。
【００４７】
次に、凝縮器１５の具体的構成を説明すると、凝縮器１５は多数の冷媒流路を並列に形成する一般にマルチフロータイプと称されるタイプの熱交換器構成であって、凝縮器１５は水平方向に延びて冷媒流路を構成する多数本の偏平チューブ１６とこれに接合されるコルゲートフィン１７とにより熱交換部１８を構成している。
【００４８】
この熱交換部１８の左右両側にヘッダタンク（サイドタンク）１９、２０を上下方向に配置している。偏平チューブ１６の左右両端部をヘッダタンク１９、２０に接合するとともに、偏平チューブ１６内の冷媒流路の左右の端部をそれぞれヘッダタンク１９、２０の内部に連通する。
【００４９】
一方のヘッダタンク１９の内部空間は２枚の仕切り板２１ａ、２１ｂにより上中下３つの空間１９ａ、１９ｂ、１９ｃに仕切られている。ここで、上部空間１９ａには接続ジョイント１４の上部通路穴１４ａが連通しているので、吐出冷媒ガスの一部が凝縮用吐出ガス通路１１から上部通路穴１４ａを通過して上部空間１９ａへ流入する。
【００５０】
また、他方のヘッダタンク２０の内部空間は１枚の仕切り板２２により上下２つの空間２０ａ、２０ｂに仕切られている。一方のヘッダタンク１９内の下側仕切り板２１ｂと他方のヘッダタンク２０内の仕切り板２２は、タンク上下方向において同一高さに配置され、この両仕切り板２１ｂ、２２の上側、すなわち、熱交換部１８の上側領域に第１熱交換部１８ａを構成し、両仕切り板２１ｂ、２２の下側、すなわち、熱交換部１８の下側領域に第２熱交換部１８ｂを構成している。
【００５１】
第１熱交換部１８ａでは、一方のヘッダタンク１９の上部空間１９ａに流入した吐出冷媒ガスが矢印ａのように偏平チューブ１６および他方のヘッダタンク２０の上部空間２０ａを通過してＵターン状に流れるようになっている。吐出冷媒ガスはこの間に冷却空気中に放熱して凝縮され、液冷媒が一方のヘッダタンク１９の中間部空間１９ｂに流入する。
【００５２】
この中間部空間１９ｂは接続ジョイント１４の下部通路穴１４ｂおよび液冷媒通路１２を通して気液分離器２の気液混合部１３に連通しているので、第１熱交換部１８ａで凝縮した液冷媒の全量が気液混合部１３に流入する。
【００５３】
一方のヘッダタンク１９のうち下部空間１９ｃに対応する部位に、気液分離器２からの戻し冷媒の入口部をなす戻し冷媒入口ジョイント２３が接合され、この戻し冷媒入口ジョイント２３は連結パイプト２４を介して気液分離器２底部の接続ジョイント２５に接続されている。
【００５４】
気液分離器２の底部にはタンク本体４と別部品として構成された底面蓋部材２６が、図示しないＯリング等の弾性シール材を用いて気密にシール固定されている。接続ジョイント２５は、通路穴２５ａを有し、Ｏリング等の弾性シール材を介在して底面蓋部材２６の中心穴部２６ａにシール固定される。
【００５５】
一方、気液分離器２の略円形の内部空間５の中心部には、丸パイプ状の管状部材２７が上下方向に延びるように配置され、この管状部材２７の下端部が底面蓋部材２６の中心穴部２６ａに支持固定される。これにより、管状部材２７の内部通路の下端部が接続ジョイント２５の通路穴２５ａに連通する。この管状部材２７の上端部は気液分離器２内部の貯留液冷媒の液面Ａよりも十分上方の部位に位置し、閉塞端面を構成している。管状部材２７の上端部より僅かに下方の外周面にガス冷媒戻し口２８が形成され、このガス冷媒戻し口２８は液面Ａより上方のガス冷媒域に開口してガス冷媒（飽和ガス）を管状部材２７内に吸入する。
【００５６】
また、管状部材２７の外周面のうち、液冷媒の液面Ａよりも十分下方の部位に液冷媒を吸入する液冷媒戻し口２９が開口しており、液冷媒（飽和液）はこの液冷媒戻し口２９から管状部材２７内に吸入され、上記ガス冷媒と混合する。従って、気液分離器２内からのガス冷媒と液冷媒が混合した状態で管状部材２７→接続ジョイント２５→連結パイプト２４→戻し冷媒入口ジョイント２３を経てヘッダタンク１９の下部空間１９ｃ内に流入する。
【００５７】
気液分離器２のタンク本体４の内部空間５において気液混合部１３の下方部に、気液混合部１３から下方へ向かう冷媒流れに旋回流Ｂを与える旋回通路３０が形成してある。この旋回通路３０は、気液混合部１３からの冷媒流れをタンク本体４の円形内周壁面の接線方向に向けて流すことにより旋回流Ｂを形成する。ガイド板３１は気液混合部１３からの冷媒がタンク本体４の円形内周壁面に沿って直接下方へ向かう流れを阻止して旋回流Ｂの形成効果を高める。
【００５８】
この旋回流Ｂにより遠心力が冷媒流れに作用して、密度の大きい液冷媒（飽和液）はタンク本体４の内周壁面に押し付けられ、タンク本体４の内周壁面に沿って下方へ落下し、タンク本体４の内部空間５の下部に溜まり、前述の液面Ａを形成する。これに対し、密度の小さいガス冷媒（飽和ガス）はタンク本体４の中心部寄りに集まって、タンク本体４の内部空間５の上部、すなわち、液冷媒の液面Ａの上方部にガス冷媒の領域を形成する。
【００５９】
このように、気液混合部１３からの流入冷媒の気液を旋回流Ｂの遠心力を利用して強制的に分離するので、気液分離器２のタンク容積が小さくても流入冷媒の気液を確実に分離できる。以上により、気液混合部１３の下方領域に遠心分離器３２が構成される。
【００６０】
タンク本体４の内部空間のうち、液冷媒の貯留領域に冷媒中に含まれる水分を吸着するための乾燥剤３３が配置されている。なお、管状部材２７、乾燥剤３３等の部品は、底面蓋部材２６を取り外すことによりタンク本体４内部へ脱着できる。
【００６１】
一方、戻し冷媒入口ジョイント２３からヘッダタンク１９の下部空間１９ｃ内に流入した、気液分離器２内からの戻し冷媒は、第２熱交換部１８ｂの偏平チューブ１６を矢印ｂのように他方のヘッダタンク２０の下部空間２０ｂへ向かって流れる。他方のヘッダタンク２０のうち下部空間２０ｂに対応する部分には出口ジョイント３４が接合され、この出口ジョイント３４から冷媒が凝縮器１５外部へ出て減圧装置３５側へ向かう。
【００６２】
なお、凝縮器１５において、熱交換部１８（第１、第２熱交換部１８ａ、１８ｂ）のチューブ１６、コルゲートフィン１７、ヘッダタンク１９、２０、接続ジョイント１４、戻し冷媒入口ジョイント２３、出口ジョイント３４等はすべてアルミニュウム材で構成され、ろう付けにより一体構造に組み付けられる。
【００６３】
一方、減圧装置３５は凝縮器１５を通過した冷媒を低圧の気液２相状態に減圧するためのものであり、本例ではオリフィス、ノズル、キャピラリーチューブ等の固定絞りで構成してある。なお、減圧装置３５を高圧冷媒の状態（圧力、温度）に応じて開度が調整される可変絞りで構成してもよい。
【００６４】
蒸発器３６は減圧装置３５を通過した低圧冷媒を図示しない空調用送風機の送風空気から吸熱して蒸発させるものである。蒸発器３６は図示しない空調室内ユニットのケース内に配置され、蒸発器３６で冷却された冷風は周知のごとく図示しないヒータコア部で温度調整された後に車室内へ吹き出す。蒸発器３６で蒸発したガス冷媒は圧縮機１に吸入される。
【００６５】
なお、凝縮器１５は車両走行による走行風を受けて冷却される部位、具体的には車両エンジンルーム内の最前部等に配置され、走行風および凝縮器用冷却ファン（図示せず）の送風空気により冷却される。
【００６６】
次に、上記構成において第１実施形態の作動を説明する。圧縮機１の吐出ガス冷媒はまず最初に高圧側の気液分離器２の冷媒入口ジョイント３からタンク本体４の上部開口部６の内側空間に流入する。
【００６７】
そして、この上部開口部６の内側空間から吐出ガス冷媒の一部は凝縮用吐出ガス通路１１および接続ジョイント１４の通路穴１４ａを通過して凝縮器１５の一方のヘッダタンク１９の上部空間１９ａ内に流入する。この上部空間１９ａの吐出冷媒ガスは矢印ａのように第１熱交換部１８ａの冷媒流路（偏平チューブ１６および他方のヘッダタンク２０の上部空間２０ａ）をＵターン状に通過して、冷却空気（外気）中に放熱する。
【００６８】
通常のサイクル運転条件であれば、吐出ガス冷媒は第１熱交換部１８ａのＵターン状の冷媒流路を流れる間に冷却空気中に放熱して凝縮されるので、この凝縮後の液冷媒がヘッダタンク１９の中間部空間１９ｂ内に流入する。この凝縮後の液冷媒の全量が中間部空間１９ｂから接続ジョイント１４の通路穴１４ｂおよび液冷媒通路１２を通過して気液分離器２の気液混合部１３に流入する。
【００６９】
一方、気液分離器２の上部開口部６の内側空間に流入した吐出ガス冷媒の残部は吐出ガスバイパス通路８を通過して気液分離器２の気液混合部１３に直接流入する。従って、この吐出ガス冷媒と、第１熱交換部１８ａを通過した凝縮後の液冷媒の全量が気液混合部１３にて混合される。
【００７０】
次に、この混合冷媒が遠心分離器３２の旋回通路３０を通過することにより、混合冷媒の気液が前述した遠心分離により液冷媒（飽和液）とガス冷媒（飽和ガス）とに分離され、液冷媒は気液分離器２内下部に溜まる。この液冷媒の一部が管状部材２７下端部付近の液冷媒戻し口２９から管状部材２７内に流入する。また、液冷媒の液面Ａの上方に溜まるガス冷媒がガス冷媒戻し口２８から管状部材２７内に流入する。
【００７１】
管状部材２７内に流入したガス冷媒と液冷媒は、接続ジョイント２５、連結パイプ２４、および戻し冷媒入口ジョイント２３を通過してヘッダタンク１９の下部空間１９ｃ内に流入する。
【００７２】
上記のガス冷媒（飽和ガス）と液冷媒（飽和液）は上記経路にて混合され、その後、第２熱交換部１８ｂの偏平チューブ１６を矢印ｂのように通過し、ここで再度大気中に放熱して過冷却状態になる。この過冷却液冷媒はヘッダタンク２０の下部空間２０ｂに流入した後、出口ジョイント３４から凝縮器１５の外部へ出て、減圧装置３５側へ向かう。
【００７３】
気液分離器２内に溜まる液冷媒の一部を液冷媒戻し口２９から第２熱交換部１８ｂに導入し、液冷媒の一部を常にサイクル循環冷媒の流れ中に戻すことにより、液冷媒に含まれる潤滑オイルを圧縮機１へ確実に戻して、圧縮機１の潤滑性を確保できる。
【００７４】
ところで、以上のような冷媒流れを形成するため、第１熱交換部１８ａを通過して凝縮した液冷媒の全量および吐出ガスバイパス通路８からの吐出ガス冷媒の一部が気液分離器２内の気液混合部１３で混合し、熱交換する。これにより、気液混合部１３で混合した冷媒は、圧縮機吐出ガス冷媒の過熱度に応じた乾き度を持った気液２相状態となる。
【００７５】
この結果、気液分離器２内に溜まる液冷媒量が圧縮機吐出ガス冷媒の過熱度に応じた量となる。換言すると、圧縮機吐出ガス冷媒の過熱度の変化に応答して気液分離器２内の液冷媒量を調整できる。この液冷媒量の調整により、気液分離器２内から第２熱交換部１８ｂへ導入されるガス冷媒量が変化してサイクル内循環冷媒流量を調整でき、これにより、圧縮機吐出ガス冷媒の過熱度を調整できる。そして、圧縮機１での圧縮過程は基本的に等エントロピ変化であるから、圧縮機１吐出ガス冷媒の過熱度を制御できれば、蒸発器出口ガス冷媒の過熱度を制御できることになる。
【００７６】
このように、サイクル高圧側に設けられる気液分離器２内に溜まる液冷媒量を調整して、サイクル内循環冷媒流量を調整する冷凍サイクル装置において、本実施形態によると、圧縮機１の吐出ガス冷媒が流入する冷媒入口ジョイント３を気液分離器２に配置し、そして、吐出ガス冷媒を第１熱交換部１８ａ側と気液分離器２側とに分配する冷媒通路構成、すなわち、凝縮用吐出ガス通路１１および吐出ガスバイパス通路８をともに気液分離器２のタンク本体４に構成している。
【００７７】
このため、凝縮器１５側に吐出ガス冷媒の分配通路構成を設定する必要がなくなり、凝縮器１５の冷媒通路構成を簡素化して製造コストを低減できる。また、吐出ガスバイパス通路８の通路断面積を凝縮器１５側の構成の変更を必要とせずに、気液分離器２のタンク本体４にて簡単に変更できる。
【００７８】
しかも、吐出ガスバイパス通路８を気液分離器２のタンク本体４に構成しているので、吐出ガスバイパス通路８が凝縮器１５のろう付け時のろう材の回り込みの影響を受けることが全くない。
【００７９】
従って、吐出ガスバイパス通路８の通路面積を凝縮器ろう付け工程の影響を受けずに切削加工当初の本来の設計値のまま維持でき、気液分離器２内へ流入する吐出ガスバイパス量を精度良く規定できる。
【００８０】
また、吐出ガスバイパス通路８は冷媒入口ジョイント３側から直接目視検査することが可能であるから、吐出ガスバイパス通路８の目詰まり異常を簡単に発見でき、不良品の出荷を防止できる。
【００８１】
更に、本実施形態では、吐出ガスバイパス通路８の製造上の寸法バラツキの影響度合いをも低減できるという利点がある。
【００８２】
この利点について具体的に説明すると、気液分離器２内に導入する凝縮後の液冷媒と吐出ガス冷媒の流入割合は、吐出ガス冷媒の過熱度変化を気液分離器２内に適切にフィードバックするために、各冷凍サイクルごとに決まる所定割合に設定する。例えば、液冷媒と吐出ガス冷媒の流入割合は、液冷媒：吐出ガス冷媒＝１：２（重量流量の割合）程度に設定する。
【００８３】
本実施形態では第１熱交換部１８ａを通過して凝縮した液冷媒の全量を気液分離器２内に導入しているため、気液分離器２内への吐出ガスバイパス量を第１熱交換部１８ａ側への吐出ガス分配量より大きな値に設定できる。これに伴って、吐出ガスバイパス量を規定する吐出ガスバイパス通路８の通路径を比較的大きな値例えば、φ５．５ｍｍ程度に増大できる。
【００８４】
ところで、吐出ガスバイパス通路８の通路径の加工に際しては、加工上の寸法バラツキが発生することは不可避である。しかし、本実施形態によると、吐出ガスバイパス通路８の通路径を上記のように比較的大きな値に増大できるので、吐出ガスバイパス通路８の通路径が加工上のバラツキで多少変化してもその変化割合を減少できる。そのため、吐出ガスバイパス通路８の通路径の変化に基づく吐出ガス冷媒バイパス量の変化割合も小さな値に抑制できる。
【００８５】
これにより、圧縮機吐出ガス冷媒の過熱度に応じてサイクル内循環冷媒流量をより一層適切に調整できる。
【００８６】
（第２実施形態）
第１実施形態では第１熱交換部１８ａを通過して凝縮した液冷媒の全量を気液分離器２内に導入しているが、第２実施形態では、第１熱交換部１８ａを通過して凝縮した液冷媒の一部のみを気液分離器２内に導入し、液冷媒の残部は第２熱交換部１８に直接導入する。
【００８７】
図３は第２実施形態を示すもので、第１実施形態と同等部分には同一符号を付して説明を省略する。凝縮器１５のヘッダタンク２０における仕切り板２２の位置を第１実施形態の位置、すなわち、ヘッダタンク１９の下側仕切り板２１ｂの位置より所定寸法だけ下方位置に変更している。
【００８８】
この結果、第２実施形態では、第１熱交換部１８ａの上半部の偏平チューブ１６を通過してヘッダタンク２０の上部空間２０ａ内に流入した冷媒が２つの流れに分岐される。すなわち、上部空間２０ａ内の冷媒の半分程度は第１熱交換部１８ａの下半部の偏平チューブ１６を通過して凝縮し、この凝縮後の液冷媒はヘッダタンク１９の中間部空間１９ｂおよび接続ジョイント１４を通過して気液分離器２側へ流れる。
【００８９】
また、ヘッダタンク２０の上部空間２０ａ内の残部の冷媒は、矢印ｃのように第２熱交換部１８ｂの上半部の偏平チューブ１６を通過してヘッダタンク１９の下部空間１９ｃ内に流入し、ここで、戻し冷媒入口ジョイント２３からの戻し冷媒と混合する。ヘッダタンク１９の下部空間１９ｃ内の冷媒は第２熱交換部１８ｂの下半部の偏平チューブ１６を矢印ｂのように通過して再度冷却され過冷却状態となる。
【００９０】
第２実施形態では、第１熱交換部１８ａで凝縮した液冷媒の一部のみを気液分離器２側に導入するので、凝縮用吐出ガス通路１１から第１熱交換部１８ａ側へ分配する吐出ガス量の方を吐出ガスバイパス通路８から気液分離器２側へ分配する吐出ガス量よりも多くする。
【００９１】
第２実施形態によると、第１実施形態における「第１熱交換部１８ａ通過後の液冷媒の全量を気液分離器２内に導入する」ことによる利点は発揮できないが、これ以外の点では第１実施形態と同様の作用効果を発揮できる。
【００９２】
なお、第２実施形態では、第１実施形態におけるガイド板３１の代わりに笠状のガイド板３１０を管状部材２７の上端部に配置し、この笠状のガイド板３１０により冷媒の気液分離を促進し、液冷媒はガイド板３１０の外周部から下方へ落下させ、空間５内の上部に溜まるガス冷媒のみを管状部材２７のガス冷媒戻し口２８に吸入させるようにしている。
【００９３】
（第３実施形態）
第１、第２実施形態では、圧縮機１の吐出ガス冷媒が流入する冷媒入口ジョイント３を気液分離器２に配置し、そして、吐出ガス冷媒の一部を第１熱交換部１８ａ側に分配する凝縮用吐出ガス通路１１および吐出ガス冷媒の残部を気液分離器２側に分配する吐出ガスバイパス通路８をともに気液分離器２のタンク本体４に構成しているが、第３実施形態では、図４、図５に示すように冷媒入口ジョイント３自体に凝縮用吐出ガス通路１１ａおよび吐出ガスバイパス通路８を構成している。
【００９４】
このため、冷媒入口ジョイント３の円筒状突出部３ａの軸方向（上下方向）寸法を第１、第２実施形態より長くして、円筒状突出部３ａの先端部（下端部）が液冷媒通路１２の開口位置付近、換言すると、気液混合部１３の直ぐ上方の部位に位置するようにしてある。
【００９５】
そして、冷媒入口ジョイント３の通路穴３ｄの先端部（下端部）付近に、通路穴３ｄよりも通路面積（通路径）を所定量だけ小さくした吐出ガスバイパス通路８を形成している。また、円筒状突出部３ａの外周面のうち、タンク本体４の上側円筒状突出部９に対向する部位に貫通穴を開けて凝縮用吐出ガス通路１１ａを形成している。この冷媒入口ジョイント３の凝縮用吐出ガス通路１１ａは、タンク本体４の凝縮用吐出ガス通路１１および接続ジョイント１４の通路穴１４ａを介してヘッダタンク１９の上部空間１９ａ内に連通する。
【００９６】
ここで、冷媒入口ジョイント３の凝縮用吐出ガス通路１１ａおよびタンク本体４の凝縮用吐出ガス通路１１の通路面積（通路径）を、接続ジョイント１４の通路穴１４ａの通路面積（通路径）より小さくしてあるので、ろう材回り込みの影響を受けない凝縮用吐出ガス通路１１、１１ａの通路面積（通路径）により第１熱交換部１８ａ側への吐出ガス分配量を規定できる。
【００９７】
また、円筒状突出部３ａの外周面のうち、凝縮用吐出ガス通路１１ａよりも先端側（下方側）部位に円周方向の外周溝部３ｅを形成して、この外周溝部３ｅに弾性シール材としてＯリング３ｆを装着している。このＯリング３ｆにより凝縮用吐出ガス通路１１ａ側の吐出ガスが円筒状突出部３ａの外周面の微小隙間から気液混合部１３側へ流入することを阻止できる。
【００９８】
なお、第３実施形態は第１実施形態と同様に第１熱交換部１８ａにて凝縮した液冷媒の全量をタンク本体４内の気液混合部１３に導入する構成としているが、第３実施形態を第２実施形態のように第１熱交換部１８ａにて凝縮した液冷媒の一部をタンク本体４内の気液混合部１３に導入する例に適用でき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実施形態による気液分離器一体型凝縮器の模式的な縦断面図である。
【図２】図１の要部拡大図である。
【図３】第２実施形態による気液分離器一体型凝縮器の模式的な縦断面図で、気液分離器の分解状態を示す。
【図４】第３実施形態による気液分離器一体型凝縮器の模式的な縦断面図である。
【図５】図４の要部拡大図である。
【図６】従来技術による冷凍サイクルの基本構成図である。
【符号の説明】
１…圧縮機、２…気液分離器、
３…吐出ガス入口ジョイント（吐出ガス入口部）、４…タンク本体、
８…吐出ガスバイパス通路、１１、１１ａ…凝縮用吐出ガス通路、
１５…凝縮器、１８ａ…第１熱交換部、１８ｂ…第２熱交換部、
２３、２４、２５、２７、２８…ガス冷媒戻し通路、２９…液冷媒戻し通路、
３５…減圧装置、３６…蒸発器。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a refrigeration cycle apparatus suitable for vehicle air conditioning and the like.
[0002]
[Prior art]
The present applicant has previously proposed a refrigeration cycle apparatus that adjusts the degree of superheat of an evaporator outlet gas refrigerant by a novel method different from the conventional receiver cycle and accumulator cycle in Patent Document 1.
[0003]
Specifically, this prior art has the basic configuration of the refrigeration cycle shown in FIG. 6, and the first and second heat exchange units 18 a and 18 b are set in the condenser 15, and the first and second The gas-liquid separator 2 is disposed between the heat exchange units 18a and 18b. Then, the main flow of the discharge gas refrigerant of the compressor 1 is caused to flow from the inlet joint 40 of the condenser 15 through the discharge gas main passage 46 to the first heat exchange unit 18a.
[0004]
A part of the liquid refrigerant condensed in the first heat exchanging portion 18 a is caused to flow into the gas-liquid separator 2 through the liquid refrigerant bypass passage 41, and a part of the discharge gas refrigerant of the compressor 1 is downstream of the inlet joint 40. Branches to the discharge gas bypass passage 42, passes through the discharge gas bypass passage 42, and allows a part of the discharge gas refrigerant to flow into the gas-liquid separator 2.
[0005]
In the gas-liquid separator 2, the condensed liquid refrigerant and the discharged gas refrigerant are mixed and heat-exchanged, and the gas-liquid of the mixed refrigerant is separated by the density difference between the gas refrigerant and the liquid refrigerant. The gas refrigerant accumulates in the lower part in the separator 2, and the gas refrigerant accumulates in the upper part in the gas-liquid separator 2.
[0006]
The second heat exchanging part 18b is connected to the downstream side of the refrigerant flow of the first heat exchanging part 18a, and the liquid refrigerant condensed in the first heat exchanging part 18a is provided on the inlet side of the second heat exchanging part 18b. The liquid refrigerant introduction passage 43 through which the main flow flows is connected. Further, the gas refrigerant return passage 44 and the liquid refrigerant return passage 45 of the gas-liquid separator 2 are connected to the inlet side of the second heat exchange unit 18b.
[0007]
Accordingly, the main flow of the liquid refrigerant condensed in the first heat exchange unit 18a, the gas refrigerant in the upper part of the gas-liquid separator 2 and the liquid refrigerant in the lower part of the gas-liquid separator 2 flow into the second heat exchange unit 18b. These refrigerants are cooled again by the second heat exchanging portion 18b and become a supercooled state. The supercooled liquid refrigerant is decompressed by the decompression device 35 to be in a low-pressure gas-liquid two-phase state. After the low-pressure refrigerant evaporates in the evaporator 36, it is sucked into the compressor 1.
[0008]
In the above prior art, since the condensed liquid refrigerant and the discharge gas refrigerant are mixed and heat exchanged in the gas-liquid separator 2, the dryness of the mixed refrigerant changes according to the superheat degree of the compressor discharge gas refrigerant. Thus, the amount of liquid refrigerant accumulated in the gas-liquid separator 2 can be adjusted according to the degree of superheat of the compressor discharge gas refrigerant. Therefore, the circulation refrigerant flow rate in the cycle is adjusted by adjusting the amount of liquid refrigerant in the gas-liquid separator 2, and as a result, the degree of superheat of the discharge gas refrigerant of the compressor and consequently the degree of superheat of the evaporator outlet gas refrigerant can be adjusted. .
[0009]
Thus, according to the prior art, the degree of superheat of the evaporator outlet gas refrigerant can be adjusted by adjusting the amount of liquid refrigerant in the gas-liquid separator 2 provided on the cycle high pressure side. A variable throttle that responds to the state of the high-pressure refrigerant can be used. Therefore, there is an advantage that it is not necessary to use an expensive temperature type expansion valve having a complicated structure as the pressure reducing device 35. Further, since the gas-liquid separator 2 is provided on the high-pressure side of the cycle where the refrigerant specific volume is small, there are also advantages that the gas-liquid separator 2 can be reduced in size compared to the low-pressure side gas-liquid separator (accumulator).
[0010]
[Patent Document 1]
JP 2002-323274 A
[0011]
[Problems to be solved by the invention]
In the above prior art, the refrigerant inlet joint 40 into which the discharge gas refrigerant of the compressor 1 flows is arranged in the condenser 15, and the main flow of the discharge gas refrigerant flows into the first heat exchange section 18a from the refrigerant inlet joint 40. The discharge gas refrigerant main passage 46 and the discharge gas bypass passage 42 through which a part of the discharge gas refrigerant flows directly from the refrigerant inlet joint 40 into the gas-liquid separator 2 are formed in the condenser 15.
[0012]
Therefore, in the prior art, since it is necessary to provide a refrigerant passage configuration for distributing the discharged gas refrigerant to the first heat exchange unit 18a side and the gas-liquid separator 2 side on the condenser 15 side, the refrigerant passage configuration of the condenser 15 is provided. However, there is a problem that the manufacturing cost increases.
[0013]
Further, in order to adjust the circulating refrigerant flow rate in the cycle according to the intended target according to the degree of superheat of the compressor discharge gas refrigerant, it is necessary to accurately define the amount of discharge gas flowing into the gas-liquid separator 2. Therefore, it is necessary to finish the passage area of the discharge gas bypass passage 42 with high accuracy.
[0014]
However, in practice, it is inevitable that the passage area of the discharge gas bypass passage 42 changes to some extent from the intended design value due to the influence of the brazing material wraparound at the time of brazing the condenser. Since the amount of discharge gas flowing into the gas-liquid separator 2 changes due to the change in the passage area of the discharge gas bypass passage 42, the in-cycle circulation refrigerant flow rate cannot be adjusted appropriately according to the degree of superheat of the compressor discharge gas refrigerant. Cause.
[0015]
For example, when the passage area of the discharge gas bypass passage 10 is reduced from the intended design value due to the wrapping of the brazing material, the ratio of the discharge gas inflow amount to the liquid refrigerant inflow amount is reduced from the predetermined set ratio, and the discharge gas refrigerant The superheat degree change cannot be properly fed back into the gas-liquid separator 2. As a result, the amount of liquid refrigerant that accumulates in the gas-liquid separator 2 with respect to the degree of superheat of the discharge gas refrigerant increases excessively, and the circulating refrigerant flow rate in the cycle becomes too small with respect to the degree of superheat of the discharge gas refrigerant. Cause a drop.
[0016]
In view of the above points, the present invention is a refrigeration cycle apparatus that adjusts the amount of liquid refrigerant accumulated in a gas-liquid separator provided on the high-pressure side of a cycle to adjust the flow rate of refrigerant circulating in the cycle. The purpose is to simplify.
[0017]
Further, the present invention provides a refrigeration cycle apparatus that adjusts the amount of liquid refrigerant accumulated in a gas-liquid separator provided on the high-pressure side of the cycle to adjust the flow rate of circulating refrigerant in the cycle. Another object is to prevent the brazing material from changing due to wraparound during brazing.
[0018]
[Means for Solving the Problems]
  In order to achieve the above object, in the first aspect of the present invention, the first heat exchange section (18a) where the discharged gas refrigerant of the compressor (1) dissipates heat and condenses, and the first heat exchange section (18a). The second heat exchange part (18b) provided on the downstream side of the refrigerant flow, a part of the discharged gas refrigerant of the compressor (1) and at least a part of the refrigerant that has passed through the first heat exchange part (18a) flow in, A gas-liquid separator (2) that separates the gas-liquid of the inflowing refrigerant and stores the liquid refrigerant, and a gas refrigerant return passage for introducing the gas refrigerant inside the gas-liquid separator (2) into the second heat exchange section (18b) ( 23, 24, 25, 27, 28), and adjusts the amount of liquid refrigerant accumulated in the gas-liquid separator (2) according to the degree of superheat of the refrigerant discharged from the compressor (1).
  The gas-liquid separator (2) has a tank body (4) that forms a gas-liquid separation space (5) for the incoming refrigerant,
  Discharge gas inlet into which the discharge gas refrigerant of the compressor (1) flowsJoint(3)Is assembled to the tank body (4),
  The tank body (4) is separate from the condenser (15) having the first heat exchange part (18a) and the second heat exchange part (18b), and is fastened and fixed to the condenser (15). And
  Inside the tank body (4), a branch part that branches the discharge gas refrigerant from the discharge gas inlet joint (3) into two flows, and one discharge gas refrigerant from the branch part1st heat exchange part (18a)EntranceDischarge gas passage for condensing (11)And the other discharged gas refrigerant from the branch portion is separated into the gas-liquid separation space (5)Discharge gas bypass passage (8) for direct flow intoAnd is formed,
  Further, a refrigerant introduction passage (12) for introducing at least a part of the refrigerant that has passed through the first heat exchange section (18a) into the gas-liquid separation space (5) is formed in the tank body (4),
  Furthermore, between the discharge gas passage for condensation (11) and the inlet side of the first heat exchange section (18a), and between the outlet side of the first heat exchange section (18a) and the refrigerant introduction passage (12), respectively. It connects with the connection part provided with the O-ring seal part, and also connects the intermediate part of the gas refrigerant return passage (23, 24, 25, 27, 28) with the connection part provided with the O-ring seal part.It is characterized by that.
[0019]
  According to this, the discharge gas inletJoint(3)Assemble the tank body (4) and fasten the tank body (4) to the condenser (15).Discharge gas inletJointFrom (3)The discharge gas refrigerant branching section and the discharge gas refrigerant branched at this branching section1st heat exchange part (18a) side and gas-liquid separationSpace (5)The passages (8, 11) distributed to the sideIn tank body (4)Therefore, it is not necessary to provide such a discharge gas distribution passage part on the condenser side including the first heat exchange part (18a). Thereby, the refrigerant path structure of a condenser can be simplified and the manufacturing cost of a condenser can be reduced.
[0020]
Moreover, the condensing discharge gas passages (11, 11a) and the discharge gas bypass passage (8) can be configured outside the condenser independently of the brazing of the condenser, so that the brazing material wrap around the condenser brazing process. Not affected. Therefore, since the dimensional accuracy at the beginning of processing can be maintained as the passage area of the discharge gas bypass passage (8), a change in the passage area of the discharge gas bypass passage (8) is suppressed, and the circulating refrigerant flow rate in the cycle is set to the compressor discharge gas refrigerant. Can be adjusted appropriately according to the degree of superheat.
[0022]
  In the first aspect of the present invention, the condensation discharge gas passage (11) and the discharge gas bypass passage (8) are formed inside the tank body (4).The condensing discharge gas passage (11) and the discharge gas bypass passage (8) can be formed integrally with the tank body (4). Therefore, the following claims2Compared with the discharge gas inletJointThe shape of (3) can be made into a simple shape having a general versatility.
[0023]
  Claim2Invention described inThen, the 1st heat exchange part (18a) in which the discharge gas refrigerant of a compressor (1) dissipates heat and condenses, and the 2nd heat exchange part (18b) provided in the refrigerant | coolant flow downstream of a 1st heat exchange part (18a). ) And a portion of the refrigerant discharged from the compressor (1) and at least a portion of the refrigerant that has passed through the first heat exchanging portion (18a) flow in, and the gas and liquid of the inflowing refrigerant are separated to collect the liquid refrigerant. A liquid separator (2) and a gas refrigerant return passage (23, 24, 25, 27, 28) for introducing the gas refrigerant in the gas-liquid separator (2) into the second heat exchange section (18b), In the refrigeration cycle apparatus that adjusts the amount of liquid refrigerant accumulated in the gas-liquid separator (2) according to the degree of superheat of the discharge gas refrigerant of the compressor (1),
  The gas-liquid separator (2) has a tank body (4) that forms a gas-liquid separation space (5) for the incoming refrigerant,
  The discharge gas inlet joint (3) into which the discharge gas refrigerant of the compressor (1) flows is assembled in a tank body (4) with a tightening and fixing structure having an O-ring seal portion,
  The tank body (4) is separate from the condenser (15) having the first heat exchange part (18a) and the second heat exchange part (18b), and is fastened and fixed to the condenser (15). And
  Inside the discharge gas inlet joint (3), a branch part that branches the discharge gas refrigerant into two flows, and one discharge gas refrigerant from the branch part flows toward the inlet side of the first heat exchange part (18a). A condensing discharge gas passage (11a) and a discharge gas bypass passage (8) for allowing the other discharge gas refrigerant from the branch portion to directly flow into the gas-liquid separation space (5) are formed.,
  The tank body (4) includes a tank-side condensing discharge gas passage (11) that connects the condensing discharge gas passage (11a) and the inlet side of the first heat exchanging portion (18a), and a first heat exchanging portion ( A refrigerant introduction passage (12) for introducing at least a part of the refrigerant that has passed through 18a) into the gas-liquid separation space (5) is formed.,
  Further, between the tank side condensation discharge gas passage (11) and the inlet side of the first heat exchange section (18a), and between the outlet side of the first heat exchange section (18a) and the refrigerant introduction passage (12). Are connected by a connecting portion having an O-ring seal portion, and the intermediate portions of the gas refrigerant return passages (23, 24, 25, 27, 28) are also connected by a connecting portion having an O-ring seal portion. And
[0024]
  Also in the invention according to the second aspect, the same effect as that of the first aspect can be exhibited. Particularly, in the invention according to claim 2, since the discharge gas passage (11a) and the discharge gas bypass passage (8) for condensation are formed in the discharge gas inlet joint (3),Discharge gas inletJointThe specifications of the condensing discharge gas passage (11a) and the discharge gas bypass passage (8) can be changed only by changing (3). Therefore, it is possible to very easily cope with a change in specifications of the refrigeration cycle.
[0025]
  Claim3In the invention described inIn claim 1 or 2,The total amount of the refrigerant that has passed through the first heat exchange section (18a) is caused to flow into the gas-liquid separator (2).
[0026]
According to this, since the whole amount of the liquid refrigerant condensed through the first heat exchange section (18a) flows into the gas-liquid separator (2), the amount of liquid refrigerant introduced into the gas-liquid separator (2). Is significantly increased compared to the above-described prior art. For this reason, the distribution amount of the discharge gas refrigerant into the gas-liquid separator (2) can be greatly increased as compared with the above-described prior art, and accordingly, the passage area of the discharge gas bypass passage (8) (Path diameter) can be made significantly larger than the discharge gas bypass passage (42) in the prior art described above.
[0027]
  Therefore, the claim3Then, even if the passage area changes to some extent from the intended design value due to the dimensional variation in processing of the discharge gas bypass passage (8), the rate of change of the passage area with respect to the intended design value can be made sufficiently small. .
[0028]
As a result, the change rate of the discharge gas refrigerant distribution amount based on the change in the passage area can be greatly reduced as compared with the above-described conventional technology. As a result, the change rate of the discharge gas inflow amount into the gas-liquid separator (2) This can reduce the degree of influence of dimensional variations in manufacturing on the adjustment of the circulating refrigerant flow rate in the cycle.
[0029]
In other words, since the necessity for finishing the dimensions of the discharge gas bypass passage (8) with high accuracy is reduced, the processing cost of the discharge gas bypass passage (8) can be reduced.
[0030]
  Claim4As in the invention described in claim 1,Or 2, Only a part of the refrigerant that has passed through the first heat exchanging part (18a) is caused to flow into the gas-liquid separator (2), and the remaining part of the refrigerant that has passed through the first heat exchanging part (18a) is taken as the second heat exchanging part. It may be allowed to flow into (18b).
[0031]
  Claim5In the invention described in claim 1, the claims 1 to4Any one of the liquid refrigerant return passage (29) for taking out part of the liquid refrigerant accumulated in the gas-liquid separator (2), and the liquid refrigerant return passage (29) is connected to the gas refrigerant return passage (23, 24, 25, 27, 28), and the gas refrigerant and the liquid refrigerant in the gas-liquid separator (2) are merged and introduced into the second heat exchange section (18b).
[0032]
Thereby, since the lubricating oil contained in the liquid refrigerant accumulated in the gas-liquid separator (2) can always be recirculated into the cycle circulation refrigerant, the lubricity of the compressor (1) can be reliably ensured. Moreover, since the gas refrigerant and the liquid refrigerant in the gas-liquid separator (2) are merged and introduced into the second heat exchange section (18b), the liquid refrigerant return passage (29) can be easily configured.
[0033]
In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.
[0034]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
FIG. 1 is a diagram showing a specific configuration of a high-pressure side gas-liquid separator and a condenser and a basic configuration of a refrigeration cycle apparatus according to the first embodiment, and shows a case where it is applied to a vehicle air conditioning refrigeration cycle. FIG. 2 is an enlarged view of a main part of FIG.
[0035]
The compressor 1 of the refrigeration cycle apparatus is belt-driven by a vehicle engine (not shown) via an electromagnetic clutch 1a. The high-temperature and high-pressure gas refrigerant discharged from the compressor 1 first flows into the refrigerant inlet joint 3 of the high-pressure side gas-liquid separator 2.
[0036]
Here, the gas-liquid separator 2 has a tank body 4, and this tank body 4 is formed in a vertically long, generally cylindrical shape that extends in the vertical direction by a metal such as aluminum, and is used for gas-liquid separation of refrigerant and storage of liquid refrigerant. A gas-liquid separation space 5 is formed. A circular upper opening 6 is formed in the upper wall of the tank body 4, and the cylindrical protrusion 3 a of the refrigerant inlet joint 3 is fitted into the upper opening 6. An outer circumferential groove 3b in the circumferential direction is formed in the cylindrical projection 3a, and an O-ring 3c is attached to the outer circumferential groove 3b as an elastic seal material. The O-ring 3c allows the cylindrical projection 3a and the upper opening 6 to be formed. Holds the seal between the inner wall surface.
[0037]
The refrigerant inlet joint 3 is fastened and fixed to the upper wall portion of the tank body 4 by a bolt (not shown). The refrigerant inlet joint 3 has a passage hole 3 d penetrating in the axial direction (vertical direction) of the cylindrical protrusion 3 a, and the discharged gas refrigerant of the compressor 1 passes through the passage hole 3 d to be inside the upper opening 6. Flow into.
[0038]
A ring-shaped plate portion 7 is formed so as to protrude inward of the inner space of the upper opening portion 6 at a position below the upper end surface of the upper opening portion 6 by a predetermined dimension. And a discharge gas bypass passage 8 is formed. Here, the ring-shaped plate portion 7 can be integrally formed with the tank body 4 by die casting or the like. Then, a minute hole is formed with high accuracy in the center of the ring-shaped plate portion 7 by cutting to form the discharge gas bypass passage 8.
[0039]
The discharge gas bypass passage 8 divides a part of the discharge gas refrigerant that has flowed into the inner space of the upper opening 6 and directly flows (bypass) the refrigerant into the gas-liquid separation space 5. The discharge gas refrigerant inflow amount (bypass amount) to the gas-liquid separation space 5 side can be defined by the passage area (hole opening area).
[0040]
Out of the upper side wall 4a of the tank body 4, the upper side (upstream side) part and the lower side (downstream side) part of the discharge gas bypass passage 8 project toward one header tank 19 side of a condenser 15 to be described later. Cylindrical protrusions 9 and 10 are integrally formed. A condensing discharge gas passage 11 is formed by opening a through hole in the central portion of the cylindrical protrusion 9 on the upper side of the cylindrical protrusions 9 and 10.
[0041]
The distribution ratio of the discharge gas to both the passages 8 and 11 is defined by the ratio of the passage area of the condensing discharge gas passage 11 and the passage area of the discharge gas bypass passage 8. In this embodiment, the distribution amount of the discharge gas in the discharge gas bypass passage 8 is larger than the distribution amount of the discharge gas to the discharge gas passage 11 for condensation.
[0042]
In addition, a liquid refrigerant passage 12 is formed by opening a through hole in the central portion of the cylindrical projection 10 on the lower side of the cylindrical projections 9 and 10. The liquid refrigerant passage 12 introduces the entire amount of the liquid refrigerant condensed in the first heat exchanging portion 18 a of the condenser 15 into the gas-liquid mixing portion 13 immediately below the discharge gas bypass passage 8 in the space 5 in the tank body 4. Is.
[0043]
Both cylindrical protrusions 9 and 10 are respectively formed with circumferential groove portions 9a and 10a in the circumferential direction, and O-rings 9b and 10b are mounted as elastic seal materials on the circumferential groove portions 9a and 10a, respectively.
[0044]
The connection joint 14 is formed of a metal such as aluminum and is joined to one header tank 19 of the condenser 15 by brazing. The connection joint 14 is formed with circular passage holes 14a and 14b for fitting the cylindrical protrusions 9 and 10 of the tank body 4 together. The passage areas of the passage holes 14a and 14b are larger than the passage areas of the condensing discharge gas passage 11 and the liquid refrigerant passage 12 by a predetermined amount.
[0045]
The inner peripheral wall surfaces of the passage holes 14a and 14b of the connection joint 14 and the cylindrical protrusions 9 and 10 are sealed by O-rings 9b and 10b. The tank body 4 is fastened and fixed to the connection joint 14 by a bolt (not shown).
[0046]
Circular fitting projections 14c and 14d are formed on the end face of the connection joint 14 on the header tank 19 side corresponding to the passage holes 14a and 14b, respectively. The fitting projections 14c and 14d are fitted to the header tank 19. The connection joint 14 is joined to the header tank 19 by brazing in a state of being fitted into a hole (not shown).
[0047]
Next, a specific configuration of the condenser 15 will be described. The condenser 15 is a heat exchanger configuration of a type generally called a multiflow type in which a large number of refrigerant flow paths are formed in parallel. A number of flat tubes 16 that extend in the horizontal direction and constitute a refrigerant flow path and corrugated fins 17 joined to the flat tubes 16 constitute a heat exchange section 18.
[0048]
Header tanks (side tanks) 19 and 20 are arranged in the vertical direction on both the left and right sides of the heat exchange unit 18. The left and right ends of the flat tube 16 are joined to the header tanks 19 and 20, and the left and right ends of the refrigerant flow path in the flat tube 16 are communicated with the header tanks 19 and 20, respectively.
[0049]
The internal space of one header tank 19 is partitioned into three spaces 19a, 19b, and 19c by upper and middle spaces by two partition plates 21a and 21b. Here, since the upper passage hole 14a of the connection joint 14 communicates with the upper space 19a, a part of the discharged refrigerant gas flows into the upper space 19a from the condensation discharge gas passage 11 through the upper passage hole 14a. To do.
[0050]
Further, the internal space of the other header tank 20 is partitioned into two upper and lower spaces 20 a and 20 b by a single partition plate 22. The lower partition plate 21b in one header tank 19 and the partition plate 22 in the other header tank 20 are arranged at the same height in the vertical direction of the tank, and the upper side of the partition plates 21b and 22, that is, heat exchange. The first heat exchanging portion 18a is configured in the upper region of the portion 18, and the second heat exchanging portion 18b is configured in the lower region of the partition plates 21b and 22, that is, in the lower region of the heat exchanging portion 18.
[0051]
In the first heat exchanging portion 18a, the discharged refrigerant gas that has flowed into the upper space 19a of one header tank 19 passes through the flat tube 16 and the upper space 20a of the other header tank 20 in the U-turn shape as indicated by an arrow a. It comes to flow. During this time, the discharged refrigerant gas dissipates heat and is condensed in the cooling air, and the liquid refrigerant flows into the intermediate space 19 b of one header tank 19.
[0052]
Since this intermediate space 19b communicates with the gas-liquid mixing section 13 of the gas-liquid separator 2 through the lower passage hole 14b of the connection joint 14 and the liquid refrigerant path 12, the liquid refrigerant condensed in the first heat exchange section 18a The entire amount flows into the gas-liquid mixing unit 13.
[0053]
A return refrigerant inlet joint 23 that forms an inlet portion of the return refrigerant from the gas-liquid separator 2 is joined to a portion of the header tank 19 corresponding to the lower space 19 c, and the return refrigerant inlet joint 23 connects the connection pipe 24. To the connection joint 25 at the bottom of the gas-liquid separator 2.
[0054]
A bottom cover member 26 configured as a separate part from the tank body 4 is hermetically sealed and fixed to the bottom of the gas-liquid separator 2 using an elastic seal material such as an O-ring (not shown). The connection joint 25 has a passage hole 25a, and is fixed to the center hole portion 26a of the bottom cover member 26 with an elastic sealing material such as an O-ring interposed.
[0055]
On the other hand, a round pipe-shaped tubular member 27 is disposed in the center of the substantially circular inner space 5 of the gas-liquid separator 2 so as to extend in the vertical direction, and the lower end portion of the tubular member 27 is the bottom cover member 26. It is supported and fixed in the center hole portion 26a. As a result, the lower end portion of the internal passage of the tubular member 27 communicates with the passage hole 25 a of the connection joint 25. The upper end portion of the tubular member 27 is located at a position sufficiently above the liquid level A of the stored liquid refrigerant in the gas-liquid separator 2 and constitutes a closed end surface. A gas refrigerant return port 28 is formed on the outer peripheral surface slightly below the upper end portion of the tubular member 27, and the gas refrigerant return port 28 opens into the gas refrigerant region above the liquid level A to allow gas refrigerant (saturated gas) to flow. Inhale into the tubular member 27.
[0056]
In addition, a liquid refrigerant return port 29 for sucking the liquid refrigerant is opened in a portion of the outer peripheral surface of the tubular member 27 that is sufficiently below the liquid surface A of the liquid refrigerant, and the liquid refrigerant (saturated liquid) is the liquid refrigerant. It is sucked into the tubular member 27 from the return port 29 and mixed with the gas refrigerant. Accordingly, the gas refrigerant and the liquid refrigerant from the gas-liquid separator 2 are mixed and flow into the lower space 19c of the header tank 19 through the tubular member 27 → the connection joint 25 → the connection pipe 24 → the return refrigerant inlet joint 23. .
[0057]
In the internal space 5 of the tank main body 4 of the gas-liquid separator 2, a swirl passage 30 is provided in the lower part of the gas-liquid mixing unit 13 to give a swirling flow B to the refrigerant flow downward from the gas-liquid mixing unit 13. The swirling passage 30 forms a swirling flow B by causing the refrigerant flow from the gas-liquid mixing unit 13 to flow toward the tangential direction of the circular inner peripheral wall surface of the tank body 4. The guide plate 31 prevents the refrigerant from the gas-liquid mixing unit 13 from flowing directly downward along the circular inner peripheral wall surface of the tank body 4 to enhance the effect of forming the swirl flow B.
[0058]
Centrifugal force acts on the refrigerant flow by the swirling flow B, and the liquid refrigerant (saturated liquid) having a high density is pressed against the inner peripheral wall surface of the tank body 4 and falls downward along the inner peripheral wall surface of the tank body 4. The liquid level A is formed in the lower part of the internal space 5 of the tank body 4. On the other hand, the low-density gas refrigerant (saturated gas) gathers near the center of the tank body 4, and the gas refrigerant is placed above the internal space 5 of the tank body 4, that is, above the liquid surface A of the liquid refrigerant. Form a region.
[0059]
As described above, the gas-liquid of the inflowing refrigerant from the gas-liquid mixing unit 13 is forcibly separated using the centrifugal force of the swirl flow B, so The liquid can be reliably separated. As described above, the centrifuge 32 is configured in the lower region of the gas-liquid mixing unit 13.
[0060]
Of the internal space of the tank body 4, a desiccant 33 for adsorbing moisture contained in the refrigerant is disposed in the liquid refrigerant storage region. It should be noted that components such as the tubular member 27 and the desiccant 33 can be detached from the tank body 4 by removing the bottom cover member 26.
[0061]
On the other hand, the return refrigerant flowing from the return refrigerant inlet joint 23 into the lower space 19c of the header tank 19 from the gas-liquid separator 2 moves the flat tube 16 of the second heat exchange part 18b to the other side as indicated by the arrow b. It flows toward the lower space 20b of the header tank 20. An outlet joint 34 is joined to a portion of the other header tank 20 corresponding to the lower space 20b, and the refrigerant exits the condenser 15 from the outlet joint 34 toward the decompression device 35 side.
[0062]
In the condenser 15, the tube 16, the corrugated fins 17, the header tanks 19 and 20, the connection joint 14, the return refrigerant inlet joint 23, and the outlet joint of the heat exchange section 18 (first and second heat exchange sections 18 a and 18 b). 34 etc. are all made of an aluminum material, and are assembled into an integral structure by brazing.
[0063]
On the other hand, the decompression device 35 is for decompressing the refrigerant that has passed through the condenser 15 into a low-pressure gas-liquid two-phase state. In this example, the decompression device 35 is composed of a fixed throttle such as an orifice, a nozzle, or a capillary tube. Note that the decompression device 35 may be configured with a variable throttle whose opening degree is adjusted according to the state (pressure, temperature) of the high-pressure refrigerant.
[0064]
The evaporator 36 evaporates the low-pressure refrigerant that has passed through the decompression device 35 by absorbing heat from air blown from an air-conditioning blower (not shown). The evaporator 36 is disposed in a case of an air conditioning indoor unit (not shown), and the cool air cooled by the evaporator 36 is blown out into the vehicle compartment after the temperature is adjusted by a heater core (not shown) as is well known. The gas refrigerant evaporated by the evaporator 36 is sucked into the compressor 1.
[0065]
Note that the condenser 15 is disposed at a portion that is cooled by the traveling wind generated by the traveling of the vehicle, specifically, the foremost portion in the vehicle engine room, and the blowing air of the traveling wind and the condenser cooling fan (not shown). It is cooled by.
[0066]
Next, the operation of the first embodiment in the above configuration will be described. The discharged gas refrigerant of the compressor 1 first flows into the inner space of the upper opening 6 of the tank body 4 from the refrigerant inlet joint 3 of the high-pressure side gas-liquid separator 2.
[0067]
A part of the discharge gas refrigerant from the inner space of the upper opening 6 passes through the discharge gas passage 11 for condensation and the passage hole 14 a of the connection joint 14, and is in the upper space 19 a of one header tank 19 of the condenser 15. Flow into. The refrigerant gas discharged from the upper space 19a passes through the refrigerant flow path (the flat tube 16 and the upper space 20a of the other header tank 20) of the first heat exchanging portion 18a in a U-turn shape as indicated by an arrow a. Dissipate heat in (outside air).
[0068]
Under normal cycle operation conditions, the discharged gas refrigerant dissipates heat and condenses into the cooling air while flowing through the U-turn-like refrigerant flow path of the first heat exchange unit 18a. It flows into the intermediate space 19 b of the header tank 19. The entire amount of the liquid refrigerant after the condensation passes through the passage hole 14b of the connection joint 14 and the liquid refrigerant passage 12 from the intermediate space 19b and flows into the gas-liquid mixing portion 13 of the gas-liquid separator 2.
[0069]
On the other hand, the remaining portion of the discharge gas refrigerant that has flowed into the inner space of the upper opening 6 of the gas-liquid separator 2 passes through the discharge gas bypass passage 8 and directly flows into the gas-liquid mixing portion 13 of the gas-liquid separator 2. Therefore, the gas-liquid mixing unit 13 mixes the discharged gas refrigerant and the total amount of the condensed liquid refrigerant that has passed through the first heat exchange unit 18a.
[0070]
Next, when this mixed refrigerant passes through the swirl passage 30 of the centrifuge 32, the gas-liquid of the mixed refrigerant is separated into liquid refrigerant (saturated liquid) and gas refrigerant (saturated gas) by the above-described centrifugation, The liquid refrigerant accumulates in the lower part of the gas-liquid separator 2. A part of the liquid refrigerant flows into the tubular member 27 from the liquid refrigerant return port 29 near the lower end of the tubular member 27. Further, the gas refrigerant that accumulates above the liquid level A of the liquid refrigerant flows into the tubular member 27 from the gas refrigerant return port 28.
[0071]
The gas refrigerant and the liquid refrigerant that have flowed into the tubular member 27 pass through the connection joint 25, the connection pipe 24, and the return refrigerant inlet joint 23 and flow into the lower space 19 c of the header tank 19.
[0072]
The gas refrigerant (saturated gas) and the liquid refrigerant (saturated liquid) are mixed in the path, and then pass through the flat tube 16 of the second heat exchanging portion 18b as shown by the arrow b, where it again enters the atmosphere. Dissipates heat and becomes supercooled. The supercooled liquid refrigerant flows into the lower space 20b of the header tank 20, and then exits from the outlet joint 34 to the outside of the condenser 15 toward the decompression device 35.
[0073]
A part of the liquid refrigerant accumulated in the gas-liquid separator 2 is introduced into the second heat exchange unit 18b from the liquid refrigerant return port 29, and a part of the liquid refrigerant is always returned to the flow of the cycle circulation refrigerant to thereby obtain the liquid refrigerant. The lubricating oil contained in is reliably returned to the compressor 1 and the lubricity of the compressor 1 can be ensured.
[0074]
By the way, in order to form the refrigerant flow as described above, the total amount of the liquid refrigerant condensed through the first heat exchange section 18a and a part of the discharge gas refrigerant from the discharge gas bypass passage 8 are contained in the gas-liquid separator 2. The gas-liquid mixing unit 13 mixes and heat-exchanges. Thereby, the refrigerant mixed in the gas-liquid mixing unit 13 becomes a gas-liquid two-phase state having a dryness corresponding to the degree of superheat of the compressor discharge gas refrigerant.
[0075]
As a result, the amount of liquid refrigerant accumulated in the gas-liquid separator 2 becomes an amount corresponding to the degree of superheat of the compressor discharge gas refrigerant. In other words, the amount of liquid refrigerant in the gas-liquid separator 2 can be adjusted in response to a change in the degree of superheat of the compressor discharge gas refrigerant. By adjusting the amount of liquid refrigerant, the amount of gas refrigerant introduced from the gas-liquid separator 2 to the second heat exchanging portion 18b can be changed to adjust the flow rate of circulating refrigerant in the cycle. The degree of superheat can be adjusted. Since the compression process in the compressor 1 is basically an isentropic change, if the superheat degree of the compressor 1 discharge gas refrigerant can be controlled, the superheat degree of the evaporator outlet gas refrigerant can be controlled.
[0076]
As described above, in the refrigeration cycle apparatus that adjusts the amount of refrigerant circulating in the cycle by adjusting the amount of liquid refrigerant accumulated in the gas-liquid separator 2 provided on the high-pressure side of the cycle, according to the present embodiment, the discharge of the compressor 1 is performed. The refrigerant inlet joint 3 into which the gas refrigerant flows is arranged in the gas-liquid separator 2, and the refrigerant passage configuration for distributing the discharged gas refrigerant to the first heat exchange section 18a side and the gas-liquid separator 2 side, that is, condensation The discharge gas passage 11 and the discharge gas bypass passage 8 are both configured in the tank body 4 of the gas-liquid separator 2.
[0077]
For this reason, it is not necessary to set the distribution passage configuration of the discharge gas refrigerant on the condenser 15 side, and the refrigerant passage configuration of the condenser 15 can be simplified to reduce the manufacturing cost. Further, the passage cross-sectional area of the discharge gas bypass passage 8 can be easily changed by the tank body 4 of the gas-liquid separator 2 without the need for changing the configuration on the condenser 15 side.
[0078]
Moreover, since the discharge gas bypass passage 8 is configured in the tank body 4 of the gas-liquid separator 2, the discharge gas bypass passage 8 is not affected by the wraparound of the brazing material when the condenser 15 is brazed. .
[0079]
Therefore, the passage area of the discharge gas bypass passage 8 can be maintained at the original design value at the beginning of cutting without being affected by the condenser brazing process, and the amount of discharge gas bypass flowing into the gas-liquid separator 2 can be accurately determined. Can be well defined.
[0080]
In addition, since the discharge gas bypass passage 8 can be directly visually inspected from the refrigerant inlet joint 3 side, a clogging abnormality in the discharge gas bypass passage 8 can be easily found, and shipment of defective products can be prevented.
[0081]
Furthermore, in this embodiment, there is an advantage that the degree of influence of dimensional variation in manufacturing of the discharge gas bypass passage 8 can be reduced.
[0082]
This advantage will be described in detail. The inflow ratio of the condensed liquid refrigerant and the discharge gas refrigerant introduced into the gas-liquid separator 2 appropriately feeds back the change in superheat degree of the discharge gas refrigerant into the gas-liquid separator 2. In order to do this, a predetermined ratio determined for each refrigeration cycle is set. For example, the inflow ratio between the liquid refrigerant and the discharge gas refrigerant is set to about liquid refrigerant: discharge gas refrigerant = 1: 2 (weight flow rate ratio).
[0083]
In the present embodiment, since the entire amount of the liquid refrigerant condensed after passing through the first heat exchanging portion 18a is introduced into the gas-liquid separator 2, the discharge gas bypass amount to the gas-liquid separator 2 is set to the first heat. It can be set to a value larger than the discharge gas distribution amount to the exchange unit 18a side. Accordingly, the diameter of the discharge gas bypass passage 8 that defines the discharge gas bypass amount can be increased to a relatively large value, for example, about φ5.5 mm.
[0084]
By the way, when machining the diameter of the discharge gas bypass passage 8, it is inevitable that variations in dimensions occur during machining. However, according to the present embodiment, since the passage diameter of the discharge gas bypass passage 8 can be increased to a relatively large value as described above, even if the passage diameter of the discharge gas bypass passage 8 changes slightly due to processing variations, The rate of change can be reduced. Therefore, the change rate of the discharge gas refrigerant bypass amount based on the change in the passage diameter of the discharge gas bypass passage 8 can also be suppressed to a small value.
[0085]
Thereby, the circulation refrigerant flow in a cycle can be adjusted more appropriately according to the degree of superheat of a compressor discharge gas refrigerant.
[0086]
(Second Embodiment)
In the first embodiment, the entire amount of liquid refrigerant condensed through the first heat exchange unit 18a is introduced into the gas-liquid separator 2, but in the second embodiment, the liquid refrigerant passes through the first heat exchange unit 18a. Then, only a part of the liquid refrigerant condensed is introduced into the gas-liquid separator 2, and the remaining liquid refrigerant is directly introduced into the second heat exchange unit 18.
[0087]
FIG. 3 shows the second embodiment, and the same parts as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted. The position of the partition plate 22 in the header tank 20 of the condenser 15 is changed to a position below the position of the first embodiment, that is, the position of the lower partition plate 21b of the header tank 19 by a predetermined dimension.
[0088]
As a result, in the second embodiment, the refrigerant that has flowed into the upper space 20a of the header tank 20 through the flat tube 16 in the upper half of the first heat exchange unit 18a is branched into two flows. That is, about half of the refrigerant in the upper space 20a is condensed by passing through the flat tube 16 in the lower half of the first heat exchanging portion 18a, and the condensed liquid refrigerant is connected to the intermediate space 19b of the header tank 19 and the connection. It passes through the joint 14 and flows to the gas-liquid separator 2 side.
[0089]
Further, the remaining refrigerant in the upper space 20a of the header tank 20 flows into the lower space 19c of the header tank 19 through the flat tube 16 in the upper half of the second heat exchange portion 18b as indicated by an arrow c. Here, the refrigerant is mixed with the return refrigerant from the return refrigerant inlet joint 23. The refrigerant in the lower space 19c of the header tank 19 passes through the flat tube 16 in the lower half part of the second heat exchange part 18b as shown by the arrow b and is cooled again to be in a supercooled state.
[0090]
In the second embodiment, only a part of the liquid refrigerant condensed in the first heat exchange unit 18a is introduced to the gas-liquid separator 2 side, so that it is distributed from the condensation discharge gas passage 11 to the first heat exchange unit 18a side. The amount of discharge gas is made larger than the amount of discharge gas distributed from the discharge gas bypass passage 8 to the gas-liquid separator 2 side.
[0091]
According to the second embodiment, the advantage of “introducing the entire amount of liquid refrigerant after passing through the first heat exchange unit 18a into the gas-liquid separator 2” in the first embodiment cannot be exhibited, but in other respects The same effects as those of the first embodiment can be exhibited.
[0092]
In the second embodiment, a cap-shaped guide plate 310 is disposed at the upper end of the tubular member 27 instead of the guide plate 31 in the first embodiment, and the gas-liquid separation of the refrigerant is performed by the cap-shaped guide plate 310. The liquid refrigerant is caused to fall downward from the outer peripheral portion of the guide plate 310 so that only the gas refrigerant accumulated in the upper portion of the space 5 is sucked into the gas refrigerant return port 28 of the tubular member 27.
[0093]
(Third embodiment)
In the first and second embodiments, the refrigerant inlet joint 3 into which the discharge gas refrigerant of the compressor 1 flows is disposed in the gas-liquid separator 2, and a part of the discharge gas refrigerant is placed on the first heat exchange unit 18a side. The condensing discharge gas passage 11 to be distributed and the discharge gas bypass passage 8 for distributing the remainder of the discharge gas refrigerant to the gas-liquid separator 2 side are both configured in the tank body 4 of the gas-liquid separator 2, but the third embodiment In the embodiment, as shown in FIGS. 4 and 5, the refrigerant inlet joint 3 itself includes a condensing discharge gas passage 11 a and a discharge gas bypass passage 8.
[0094]
For this reason, the axial direction (vertical direction) dimension of the cylindrical protrusion 3a of the refrigerant inlet joint 3 is made longer than those in the first and second embodiments, and the tip (lower end) of the cylindrical protrusion 3a is the liquid refrigerant passage. 12 in the vicinity of the opening position, in other words, a position immediately above the gas-liquid mixing unit 13.
[0095]
A discharge gas bypass passage 8 having a passage area (passage diameter) smaller than the passage hole 3d by a predetermined amount is formed near the tip (lower end) of the passage hole 3d of the refrigerant inlet joint 3. Further, a condensing discharge gas passage 11a is formed by opening a through hole in a portion of the outer peripheral surface of the cylindrical protruding portion 3a facing the upper cylindrical protruding portion 9 of the tank body 4. The condensing discharge gas passage 11 a of the refrigerant inlet joint 3 communicates with the upper space 19 a of the header tank 19 through the condensing discharge gas passage 11 of the tank body 4 and the passage hole 14 a of the connection joint 14.
[0096]
Here, the passage area (passage diameter) of the condensing discharge gas passage 11 a of the refrigerant inlet joint 3 and the condensing discharge gas passage 11 of the tank body 4 is smaller than the passage area (passage diameter) of the passage hole 14 a of the connection joint 14. Therefore, the discharge gas distribution amount to the first heat exchanging portion 18a side can be defined by the passage area (passage diameter) of the condensing discharge gas passages 11 and 11a that is not affected by the brazing material wraparound.
[0097]
In addition, an outer circumferential groove 3e in the circumferential direction is formed in a distal end side (lower side) of the outer peripheral surface of the cylindrical protrusion 3a with respect to the discharge gas passage 11a for condensation, and the outer circumferential groove 3e serves as an elastic sealing material. O-ring 3f is attached. The O-ring 3f can prevent the discharge gas on the condensing discharge gas passage 11a side from flowing into the gas-liquid mixing portion 13 side from the minute gap on the outer peripheral surface of the cylindrical protrusion 3a.
[0098]
In addition, although 3rd Embodiment is set as the structure which introduces the whole quantity of the liquid refrigerant condensed in the 1st heat exchange part 18a to the gas-liquid mixing part 13 in the tank main body 4 similarly to 1st Embodiment, 3rd Embodiment Of course, the embodiment can be applied to an example in which a part of the liquid refrigerant condensed in the first heat exchange unit 18a is introduced into the gas-liquid mixing unit 13 in the tank body 4 as in the second embodiment.
[Brief description of the drawings]
FIG. 1 is a schematic longitudinal sectional view of a gas-liquid separator integrated condenser according to a first embodiment of the present invention.
FIG. 2 is an enlarged view of a main part of FIG.
FIG. 3 is a schematic longitudinal sectional view of a gas-liquid separator integrated condenser according to a second embodiment, showing a disassembled state of the gas-liquid separator.
FIG. 4 is a schematic longitudinal sectional view of a gas-liquid separator integrated condenser according to a third embodiment.
FIG. 5 is an enlarged view of a main part of FIG.
FIG. 6 is a basic configuration diagram of a conventional refrigeration cycle.
[Explanation of symbols]
1 ... Compressor, 2 ... Gas-liquid separator,
3 ... discharge gas inlet joint (discharge gas inlet), 4 ... tank body,
8 ... discharge gas bypass passage, 11, 11a ... discharge gas passage for condensation,
15 ... Condenser, 18a ... 1st heat exchange part, 18b ... 2nd heat exchange part,
23, 24, 25, 27, 28 ... gas refrigerant return passage, 29 ... liquid refrigerant return passage,
35 ... decompression device, 36 ... evaporator.

Claims

A first heat exchange section (18a) in which the discharged gas refrigerant of the compressor (1) dissipates heat and condenses;
A second heat exchange section (18b) provided downstream of the refrigerant flow of the first heat exchange section (18a);
A part of the discharged gas refrigerant of the compressor (1) and at least a part of the refrigerant that has passed through the first heat exchange part (18a) flow in, and the gas-liquid that separates the gas-liquid of the inflowing refrigerant and stores the liquid refrigerant A separator (2);
A gas refrigerant return passage (23, 24, 25, 27, 28) for introducing the gas refrigerant inside the gas-liquid separator (2) into the second heat exchange section (18b),
In the refrigeration cycle apparatus that adjusts the amount of liquid refrigerant accumulated in the gas-liquid separator (2) according to the degree of superheat of the discharge gas refrigerant of the compressor (1),
The gas-liquid separator (2) has a tank body (4) that forms a gas-liquid separation space (5) for the incoming refrigerant,
A discharge gas inlet joint (3) into which the discharge gas refrigerant of the compressor (1) flows is assembled to the tank body (4),
The tank body (4) is separate from the condenser (15) having the first heat exchange part (18a) and the second heat exchange part (18b), and is fastened and fixed to the condenser (15). Is supposed to be
Inside the tank body (4), a branch portion for branching the discharge gas refrigerant from the discharge gas inlet joint (3) into two flows, and one discharge gas refrigerant from the branch portion for the first heat exchange A condensing discharge gas passage (11) that flows into the inlet of the section (18a) , a discharge gas bypass passage (8) that allows the other discharge gas refrigerant from the branch portion to flow directly into the gas-liquid separation space (5) , and Is formed ,
Also, a refrigerant introduction passage (12) for introducing at least a part of the refrigerant that has passed through the first heat exchange part (18a) into the gas-liquid separation space (5) is formed in the tank body (4). And
Furthermore, between the discharge gas passage for condensation (11) and the inlet side of the first heat exchange section (18a), the outlet side of the first heat exchange section (18a), and the refrigerant introduction passage (12) Are connected by a connecting portion having an O-ring seal portion, and the intermediate portions of the gas refrigerant return passages (23, 24, 25, 27, 28) are also connected by a connecting portion having an O-ring seal portion. A refrigeration cycle apparatus characterized by that.

A first heat exchange section (18a) in which the discharged gas refrigerant of the compressor (1) dissipates heat and condenses;
A second heat exchange section (18b) provided downstream of the refrigerant flow of the first heat exchange section (18a);
A part of the discharged gas refrigerant of the compressor (1) and at least a part of the refrigerant that has passed through the first heat exchange part (18a) flow in, and the gas-liquid that separates the gas-liquid of the inflowing refrigerant and stores the liquid refrigerant A separator (2);
A gas refrigerant return passage (23, 24, 25, 27, 28) for introducing the gas refrigerant inside the gas-liquid separator (2) into the second heat exchange section (18b),
In the refrigeration cycle apparatus that adjusts the amount of liquid refrigerant accumulated in the gas-liquid separator (2) according to the degree of superheat of the discharge gas refrigerant of the compressor (1),
The gas-liquid separator (2) has a tank body (4) that forms a gas-liquid separation space (5) for the incoming refrigerant,
The discharge gas inlet joint (3) into which the discharge gas refrigerant of the compressor (1) flows is assembled to the tank body (4) with a fastening structure having an O-ring seal portion,
The tank body (4) is separate from the condenser (15) having the first heat exchange part (18a) and the second heat exchange part (18b), and is fastened and fixed to the condenser (15). Is supposed to be
Inside the discharge gas inlet joint (3), a branch part for branching the discharge gas refrigerant into two flows, and one discharge gas refrigerant from the branch part on the inlet side of the first heat exchange part (18a) And a discharge gas bypass passage (8) for allowing the other discharge gas refrigerant from the branch portion to directly flow into the gas-liquid separation space (5). ,
The tank body (4) includes a tank-side condensation discharge gas passage (11) that communicates the condensation discharge gas passage (11a) with the inlet side of the first heat exchange section (18a), and the first A refrigerant introduction passage (12) for introducing at least part of the refrigerant that has passed through the heat exchange section (18a) into the gas-liquid separation space (5) is formed ,
Furthermore, between the tank side condensation discharge gas passage (11) and the inlet side of the first heat exchange section (18a), and the outlet side of the first heat exchange section (18a) and the refrigerant introduction passage (12 ) Are connected by connecting portions each having an O-ring seal portion, and intermediate portions of the gas refrigerant return passages (23, 24, 25, 27, 28) are also connected by a connecting portion having an O-ring seal portion. A refrigeration cycle apparatus connected to each other.

The refrigeration cycle apparatus according to claim 1 or 2 , wherein the entire amount of the refrigerant that has passed through the first heat exchange section (18a) is caused to flow into the gas-liquid separator (2).

Only a part of the refrigerant that has passed through the first heat exchange part (18a) flows into the gas-liquid separator (2), and the remaining part of the refrigerant that has passed through the first heat exchange part (18a) is passed through the second heat. refrigeration cycle apparatus according to claim 1 or 2, characterized in that to flow into the exchange unit (18b).

A liquid refrigerant return passage (29) for taking out part of the liquid refrigerant accumulated in the gas-liquid separator (2), and the liquid refrigerant return passage (29) is connected to the gas refrigerant return passage (23, 24, 25, 27, 28)
While merging the gas refrigerant and liquid refrigerant in the gas-liquid separator (2) in, according to any one of claims 1 to 4, characterized in that introduced into the second heat exchange section (18b) Refrigeration cycle equipment.