JP4048654B2

JP4048654B2 - Refrigeration cycle equipment

Info

Publication number: JP4048654B2
Application number: JP21090999A
Authority: JP
Inventors: 誠司伊藤; 邦夫入谷
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 1999-07-26
Filing date: 1999-07-26
Publication date: 2008-02-20
Anticipated expiration: 2019-07-26
Also published as: JP2001030744A

Description

【０００１】
【発明の属する技術分野】
本発明は、暖房モードと冷房モードと除湿モードとを切替可能なヒートポンプ式の冷凍サイクル装置に関し、例えば、電気自動車用空調装置に用いて好適なものである。
【０００２】
【従来の技術】
従来、電気自動車等の車両では、エンジン廃熱（温水）を熱源として車室内の暖房を行うことができないので、ヒートポンプ式の冷凍サイクル装置を装備して、凝縮器での冷媒凝縮熱により車室内を暖房するようにしている。
【０００３】
しかし、冬季の寒冷地使用のごとく外気温が−１０°Ｃ以下に低下するような使用環境では、ヒートポンプサイクルにおいて蒸発器として作用する室外熱交換器での吸熱量が低下して、圧縮機吸入圧力が低下するので、冷媒比容積が大きくなり、冷媒循環量が減少するので、暖房能力が低下するという問題があった。このため、寒冷地使用では車室内の暖房能力が不足してしまう。
【０００４】
そこで、本出願人においては、先に、特開平９−３２８０１３号公報において、暖房時に、サイクル高圧冷媒を中間圧に減圧し、この中間圧冷媒を気液分離器にてガス冷媒と液冷媒とに分離し、この中間圧のガス冷媒を圧縮機にガスインジェクションすることにより、暖房時での圧縮機の圧縮仕事量を増大させて、暖房能力を増大させるようにした冷凍サイクル装置を提案している。
【０００５】
この従来技術では、室内空調ユニットの空気通路の上流側に冷凍サイクルの蒸発器を、また、その下流側に冷凍サイクルの凝縮器を配置して、除湿運転を実施することにより、車両窓ガラスの曇り止めを行うようにしている。
【０００６】
また、上記の従来技術では、圧縮機の吐出側に配置した四方弁により冷房時では圧縮機の吐出ガスを室外熱交換器に流入させ、また、暖房時には圧縮機の吐出ガスを室内凝縮器に流入させるように冷媒の流れ方向を切り替えている。
【０００７】
【発明が解決しようとする課題】
ところで、上記の従来技術では、暖房時に室外熱交換器に着霜が生じたときは、四方弁により冷媒流れを反転させて逆サイクル（冷房サイクル）とし、室外熱交換器の霜を圧縮機の高温吐出ガスの熱で除去するようにしている。
【０００８】
このように逆サイクルへの反転により室外熱交換器の除霜を行うので、除霜中は室内の暖房を行うことができず、暖房フィーリングを損なうという不具合がある。
【０００９】
また、上記の従来技術では、四方弁により冷房流れを切り替えて運転モードの切替を行っているので、サイクルの冷媒配管構成が煩雑になり、かつ、逆止弁等の部品点数が増加する。
【００１０】
本発明は上記点に鑑みて、第１には、室外熱交換器の除霜モードにおける室内暖房作用を確保することを目的とする。
【００１１】
また、本発明は第２には、通常暖房時における暖房能力の向上と、室外熱交換器の除霜中における室内暖房作用の確保とを両立させることを目的とする。
【００１２】
また、本発明は第３には、サイクルの冷媒通路構成の簡略化を図ることを目的とする。
【００１３】
【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、室内へ向かって空気が流れる空調通路（２）と、
冷媒を圧縮し吐出する圧縮機（２２）と、
前記空調通路（２）内に設置され、前記圧縮機（２２）からの吐出ガス冷媒により空気を加熱する凝縮器（１２）と、
前記空調通路（２）内に形成され、前記凝縮器（１２）をバイパスして空気を流すバイパス通路（１２ａ）と、
前記空調通路（２）内に設置され、前記凝縮器（１２）への空気流れと前記バイパス通路（１２ａ）への空気流れとを切り替えるドア手段（１６、１７）と、
室外に設置される室外熱交換器（２４）と、
前記室外熱交換器（２４）の冷媒入口側に設置された暖房用減圧装置（２７）と、
前記空調通路（２）内で、前記凝縮器（１２）の上流側に設置された蒸発器（１１）と、
前記蒸発器（１１）の冷媒入口側に設置された冷房用減圧装置（２９）と、
前記暖房用減圧装置（２７）をバイパスして冷媒が流れる冷媒バイパス通路（６３）と、
前記冷媒バイパス通路（６３）に設けられたバイパス側減圧装置（２６）とを備え、
前記圧縮機（２２）の吐出側を常に前記凝縮器（１２）に接続して、前記圧縮機（２２）からの吐出ガス冷媒が常に前記凝縮器（１２）を通過して前記室外熱交換器（２４）側への一方向に流れるようにし、
暖房モード時には、前記空調通路（２）内の送風空気が前記凝縮器（１２）を通過する位置に前記ドア手段（１６、１７）を切り替えることにより、前記圧縮機（２２）の吐出ガス冷媒が前記凝縮器（１２）に流入して前記空調通路（２）内の送風空気に放熱することで凝縮し、前記凝縮器（１２）通過後の高圧冷媒が前記暖房用減圧装置（２７）により減圧されて低圧状態となり、前記暖房用減圧装置（２７）通過後の低圧冷媒が前記室外熱交換器（２４）に流入して蒸発し、前記室外熱交換器（２４）通過後の低圧冷媒が前記圧縮機（２２）に吸入されるようになっており、前記暖房モードでは前記凝縮器（１２）により加熱された温風を室内へ吹き出し、
冷房モード時には、前記空調通路（２）内の送風空気が前記バイパス通路（１２ａ）を通過する位置に前記ドア手段（１６、１７）を切り替えることにより、前記圧縮機（２２）の吐出ガス冷媒が前記空調通路（２）内の送風空気と熱交換しないまま前記凝縮器（１２）を通過し、前記凝縮器（１２）通過後の吐出ガス冷媒が高圧状態のまま前記室外熱交換器（２４）に流入し、前記室外熱交換器（２４）にて前記吐出ガス冷媒が凝縮し、前記室外熱交換器（２４）通過後の高圧冷媒が前記冷房用減圧装置（２９）により減圧されて低圧状態となり、前記冷房用減圧装置（２９）通過後の低圧冷媒が前記蒸発器（１１）に流入して前記空調通路（２）内の送風空気から吸熱することで蒸発し、前記蒸発器（１１）通過後の低圧冷媒が前記圧縮機（２２）に吸入されるようになっており、前記冷房モードでは前記蒸発器（１１）により冷却された冷風が前記バイパス通路（１２ａ）を通過して室内へ吹き出し、
除湿モード時には、前記空調通路（２）内の送風空気が前記凝縮器（１２）を通過する位置に前記ドア手段（１６、１７）を切り替えることにより、前記圧縮機（２２）の吐出ガス冷媒が前記凝縮器（１２）に流入して前記空調通路（２）内の送風空気に放熱することで凝縮し、前記凝縮器（１２）通過後の高圧冷媒が前記暖房用減圧装置（２７）により減圧されて中間圧状態となり、前記暖房用減圧装置（２７）通過後の中間圧冷媒が前記室外熱交換器（２４）に流入して室外空気と熱交換し、前記室外熱交換器（２４）通過後の中間圧冷媒が前記冷房用減圧装置（２９）により減圧されて低圧状態となり、前記冷房用減圧装置（２９）通過後の低圧冷媒が前記蒸発器（１１）に流入して前記空調通路（２）内の送風空気から吸熱することで蒸発し、前記蒸発器（１１）通過後の低圧冷媒が前記圧縮機（２２）に吸入されるようになっており、前記除湿モードでは前記蒸発器（１１）により冷却除湿された冷風を前記凝縮器（１２）にて再加熱して室内へ吹き出し、
前記暖房モード時に前記室外熱交換器（２４）の除霜を行う除霜モードを設定するときは、前記空調通路（２）内の送風空気が前記バイパス通路（１２ａ）を通過する位置に前記ドア手段（１６、１７）を切り替えることにより、前記圧縮機（２２）の吐出ガス冷媒が前記空調通路（２）内の送風空気と熱交換しないまま前記凝縮器（１２）を通過し、前記凝縮器（１２）通過後の吐出ガス冷媒を、前記暖房用減圧装置（２７）に向かう流れと前記冷媒バイパス通路（６３）に向かう流れとに分岐し、
前記分岐ガス冷媒の一方が前記暖房用減圧装置（２７）により減圧されて低圧状態となり、前記暖房用減圧装置（２７）通過後の低圧状態のガス冷媒が前記室外熱交換器（２４）に流入して前記室外熱交換器（２４）の除霜を行い、前記室外熱交換器（２４）通過後の低圧冷媒が前記圧縮機（２２）に吸入されるようになっており、
また、前記分岐ガス冷媒の他方が前記冷媒バイパス通路（６３）に流入して前記バイパス側減圧装置（２６）により減圧されて低圧状態となり、前記バイパス側減圧装置（２６）通過後の低圧状態のガス冷媒が前記蒸発器（１１）に流入し、前記蒸発器（１１）にて前記空調通路（２）内の送風空気を前記低圧状態のガス冷媒により加熱し、前記蒸発器（１１）通過後の低圧冷媒も前記圧縮機（２２）に吸入されるようになっており、前記除霜モードでは前記蒸発器（１１）にて加熱された温風が前記バイパス通路（１２ａ）を通過して室内へ吹き出すことを特徴としている。
【００１４】
これによると、室外熱交換器（２４）の除霜を行いながら、同時に蒸発器（１１）による空気加熱作用により室内の暖房を続行できる。つまり、暖房モード時には蒸発器（１１）が使用されない点に着目して、本発明では除霜モード時に蒸発器（１１）を有効利用することにより、サイクルの煩雑化を招くことなく、除霜モードにおける室内暖房作用を確保することができる。
【００１５】
また、請求項１記載の発明では、冷房、除霜モード時には、ドア手段（１６、１７）により凝縮器（１２）への空気流れを遮断してバイパス通路（１２ａ）に空気を通過させることができ、そのため、凝縮器（１２）は高圧冷媒が流れる冷媒通路の一部としての役割を果たすことになる。
そのため、暖房、冷房、除湿、除霜の各モードを通じて、凝縮器（１２）に冷媒が流れたままとなり、圧縮機（２２）の吐出ガス冷媒を常に凝縮器（１２）を通して室外熱交換器（２４）へ向かう一方向に流すことができる。その結果、冷媒流れ方向逆転のための四方弁の廃止、あるいは、冷媒流れ経路切替用の逆止弁、電磁弁等の弁装置の数を低減することが可能となり、冷媒配管構成の簡素化により製品コストを低減できる。
次に、請求項２記載の発明では、請求項１において、発熱部品（８１）の廃熱を回収する第１熱交換手段（７４、３２０）を有し、
除霜モード時に、バイパス側減圧装置（２６）により減圧された低圧状態のガス冷媒が第１熱交換手段（７４、３２０）により発熱部品（８１）の廃熱を吸熱し、この廃熱を吸熱した後の低圧状態のガス冷媒が蒸発器（１１）に流入することを特徴としている。
【００１６】
これによると、除霜モード時の蒸発器（１１）による室内暖房能力を発熱部品（８１）の廃熱回収により向上できる。
【００１７】
次に、請求項３記載の発明では、請求項２において、圧縮機（２２）として、圧縮した冷媒を吐出する吐出ポート（２２ａ）、冷凍サイクル低圧側の冷媒を吸入する吸入ポート（２２ｂ）、および冷凍サイクル中間圧側のガス冷媒を導入するガスインジェクションポート（２２ｃ）を有する圧縮機を用い、
暖房モード時においても、凝縮器（１２）にて凝縮した高圧冷媒を暖房用減圧装置（２７）に向かう流れと冷媒バイパス通路（６３）に向かう流れとに分岐し、
前記分岐冷媒の一方が暖房用減圧装置（２７）により減圧されて低圧状態となって室外熱交換器（２４）に流入し、
前記分岐冷媒の他方は、バイパス側減圧装置（２６）により中間圧まで減圧し、この中間圧冷媒に第１熱交換手段（７４、３２０）により発熱部品（８１）の廃熱を吸熱させて、この中間圧冷媒をガス化し、この中間圧ガス冷媒をガスインジェクションポート（２２ｃ）に流入させるようになっており、
暖房モード時には、室外熱交換器（２４）通過後の低圧冷媒が吸入ポート（２２ｂ）に吸入され、冷房モード時には、蒸発器（１１）通過後の低圧冷媒が吸入ポート（２２ｂ）に吸入され、除霜モード時には、室外熱交換器（２４）通過後の低圧冷媒及び蒸発器（１１）通過後の低圧冷媒が吸入ポート（２２ｂ）に吸入されることを特徴としている。
【００１８】
これによると、圧縮機（２２）へのガスインジェクションによる暖房能力の向上効果と発熱部品（８１）の廃熱回収による暖房能力の向上効果とを合わせ奏することができる。そのため、通常暖房時における暖房能力の向上と、室外熱交換器の除霜中における室内暖房作用の確保とを良好に両立できる。
【００１９】
次に、請求項４記載の発明では、請求項３において、暖房モード時に、暖房用減圧装置（２７）に向かう前記一方の分岐冷媒である高圧冷媒と、バイパス側減圧装置（２６）により減圧された中間圧冷媒との間で熱交換を行う第２熱交換手段（２３、２３０）を有することを特徴としている。
【００２０】
これによると、中間圧冷媒が高圧冷媒から吸熱するとともに発熱部品（８１）の廃熱からも吸熱するので、中間圧冷媒のガス化が促進され暖房能力を効果的に向上できる。
【００２１】
次に、請求項５記載の発明では、請求項４において、第１熱交換手段と第２熱交換手段とを１つの熱交換器（２３０）として一体に構成したことを特徴としている。
【００２２】
これによると、第１、第２の熱交換手段を一体型熱交換器（２３０）により小型、簡潔に構成できる。
【００２３】
次に、請求項６記載の発明では、請求項１において、発熱部品（８１）の廃熱を回収する第１熱交換手段（７４、３２０）を有し、
暖房モード時に圧縮機（２２）に吸入される、室外熱交換器（２４）通過後の低圧冷媒に第１熱交換手段（７４、３２０）により発熱部品（８１）の廃熱を吸熱させ、
除霜モード時には、圧縮機（２２）に吸入される、室外熱交換器（２４）通過後の低圧冷媒、及び圧縮機（２２）に吸入される、蒸発器（１１）通過後の低圧冷媒に第１熱交換手段（７４、３２０）により発熱部品（８１）の廃熱を吸熱させることを特徴としている。
【００２４】
これによると、低圧側冷媒は中間圧冷媒に比して温度が低いから、発熱部品（８１）の温度が低い条件のときでも廃熱回収を行うことができる。
【００２５】
次に、請求項７記載の発明では、請求項６において、圧縮機（２２）の吸入ポート（２２ｂ）の入口側に、冷媒の気液を分離するアキュームレータ（２５）を備え、このアキュームレータ（２５）から、オイルの溶け込んだ液冷媒をガス冷媒に混合して吸入ポート（２２ｂ）に吸入させるようになっており、アキュームレータ（２５）の入口側に第１熱交換手段（７４、３２０）を配置したことを特徴としている。
【００２６】
これによると、アキュームレータ（２５）によりオイルが溶け込んだ液冷媒を低圧ガス冷媒に確実に混入させて、圧縮機（２２）の吸入ポート（２２ｂ）に送り込むことができる。その結果、圧縮機回転数の低下により室外熱交換器（２４）を流れる冷媒の流量（流速）が低下して室外熱交換器（２４）に冷媒中のオイルが溜まりやすい暖房低負荷時においても、圧縮機（２２）へのオイル戻り性を良好に確保でき、圧縮機（２２）の耐久性向上に貢献できる。しかも、アキュームレータ（２５）の入口側に第１熱交換手段（７４、３２０）を配置することにより、アキュームレータ入口側の気液２相域の冷媒（ガス域冷媒より一層低温の冷媒）に発熱部品（８１）の廃熱を吸熱させることができ、発熱部品（８１）の低温時においても廃熱回収を良好に行うことができる。
【００３０】
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。
【００３１】
【発明の実施の形態】
（第１実施形態）
図１は、本発明を電気自動車用空調装置に適用した第１実施形態で、空調ユニット１は電気自動車の車室内に設置されるもので、その空調ダクト２は、車室内に空調空気を導く空調通路を構成するものである。この空調ダクト２の一端側に内外気を吸入する吸入口３、４、５が設けられている。内気吸入口４と外気吸入口５は、内外気切替ドア６により切替開閉される。
【００３２】
上記吸入口３〜５に隣接して、空調ダクト２内に空気を送風する送風機７が設置されており、この送風機７は図示しないモ−タとこのモータにより駆動されるファン７ａ、７ｂにより構成される。
【００３３】
一方、空調ダクト２の他端側には車室内へ通ずる複数の吹出口、すなわち車室内乗員の足元部に向かって空調空気を吹き出すフット吹出口８、車室内乗員の上半身に向かって空調空気を吹き出すフェイス吹出口９および車両フロントガラスの内面に空調空気を吹き出すデフロスタ吹出口１０が形成されている。
【００３４】
また、送風機７よりも空気下流側における空調ダクト２内には冷房用蒸発器１１が設けられている。この冷房用蒸発器１１は、冷凍サイクル２１の一部を構成する室内側熱交換器であり、後述する冷房モードおよび除湿モード時に、内部を流れる冷媒の吸熱作用によって、空調ダクト２内の空気を除湿、冷却する冷却器として機能する。また、後述する除霜モード時には内部を流れる冷媒の放熱作用によって、空調ダクト２内の空気を加熱する加熱器として機能する。
【００３５】
また、冷房用蒸発器１１よりも空気下流側における空調ダクト２内には暖房用凝縮器１２が設けられている。この暖房用凝縮器１２は、冷凍サイクル２１の一部を構成する室内側熱交換器であり、後述する暖房モードおよび除湿モード時に、内部を流れる冷媒の放熱作用によって、空調ダクト２内の空気を加熱する加熱器として機能する。
【００３６】
また、空調ダクト２内の空気流路は、仕切り壁１３によりフット吹出口８側の第１空気流路１４と、フェイス吹出口９およびデフロスタ吹出口１０側の第２空気流路１５とに仕切られている。この空気流路１４、１５の２分割は冬季の暖房時に次の内外気２層モードを実施するためである。すなわち、冬季暖房時にフット吹出口８側の第１空気流路１４には内気吸入口３から温度の高い内気を吸入して足元へ温度を吹き出すことにより暖房負荷を軽減すると同時に、デフロスタ吹出口１０側の第２空気流路１５には外気吸入口５から湿度の低い外気を吸入して、フロントウインドの曇りを確実に防止する内外気２層モードを実施するために、空気流路１４、１５の２分割を行っている。
【００３７】
ドア１６、１７は凝縮器１２を通る空気通路と凝縮器１２をバイパスするバイパス通路１２ａとを切り替える通路切替ドアであり、一方のドア１７は空気流路１４、１５の仕切り部材の役割を兼ねている。また、１８は空気流路１４、１５の下流側に配置されたドアで、空気流路１４、１５の仕切り作用と空気流路１４、１５の連通状態とを切り替えるドアである。なお、前記した各吹出口８、９、１０は図示しない吹出口切替ドアにより開閉される。
【００３８】
ところで、上記冷凍サイクル２１は、冷房用の蒸発器１１と暖房用の凝縮器１２とで冷房、暖房および除湿を行うヒートポンプ式冷凍サイクルとして構成されており、蒸発器１１と凝縮器１２の他に以下の機器を備えている。
【００３９】
すなわち、冷媒圧縮機２２、気液２相の中間圧冷媒を高圧冷媒と熱交換してガス化する冷媒−冷媒熱交換器２３、室外熱交換器２４、サイクル低圧冷媒（圧縮機吸入冷媒）の気液を分離して余剰液冷媒を溜めておくアキュムレータ（気液分離器）２５、凝縮器１２通過後の高圧冷媒の一部を分岐（バイパス）させて中間圧に減圧する第１減圧装置２６、冷媒−冷媒熱交換器２３の出口の高圧冷媒を暖房時に低圧まで減圧する第２減圧装置２７、冷房時に室外熱交換器２４からの凝縮後の高圧冷媒を低圧まで減圧する第３減圧装置２９、冷房、暖房、除湿、除霜の各モードでの冷媒流れを切り替える電磁弁（冷媒経路切替手段）２８ａ、２８ｂ、２８ｃ、および水−冷媒熱交換器７４が冷凍サイクル２１に備えられている。
【００４０】
なお、室外熱交換器２４は電気自動車の車室外に設置され、電動室外ファン２４ａにより送風される外気と熱交換するようになっている。また、上記冷媒圧縮機２２は電動式圧縮機であって、図示しない交流モータを一体に密封ケース内に内蔵し、このモータにより駆動されて冷媒の吸入、圧縮、吐出を行う。この冷媒圧縮機２２の交流モータにはインバータ３０により交流電圧が印加され、このインバータ３０により交流電圧の周波数を調整することによってモータ回転速度を連続的に変化させるようになっている。従って、インバータ３０は圧縮機２２の回転数調整手段をなすものであり、このインバータ３０には、車載バッテリ３１からの直流電圧が印加される。インバータ３０は空調用制御装置４０によって通電制御される。
【００４１】
冷媒圧縮機２２には圧縮した冷媒を吐出する吐出ポート２２ａ、サイクル低圧側の冷媒を吸入する吸入ポート２２ｂ、および中間圧のガス冷媒をインジェクションするガスインジェクションポート２２ｃが備えられている。このガスインジェクションポート２２ｃは、ガスインジェクション通路２２ｄを介して冷媒−冷媒熱交換器２３に連通している。
【００４２】
第１減圧装置２６、第２減圧装置２７および第３減圧装置２９はいずれも電気的に弁開度が調整される電気式膨張弁からなり、この電気式膨張弁は例えば、ステップモータのような電気駆動手段を有し、この電気駆動手段により弁体の変位量を調整して、この弁体により冷媒絞り通路の開度を調整するものである。なお、第１〜第３減圧装置２６、２７、２９は固定絞り手段（例えば、キャピラリチューブ、オリフィス等）により構成することもできる。
【００４３】
アキュムレータ２５はＵ状の冷媒出口管２５ａを有しており、余剰液冷媒を底部側に溜めてガス冷媒をＵ状の冷媒出口管２５ａの上端開口部から吸入することにより圧縮機２２への液バックを防止する。また、同時に、アキュムレータ２５のＵ状の冷媒出口管２５ａの底部に設けた小径のオイル戻し穴（図示せず）から、オイルが溶け込んだ液冷媒を吸入してガス冷媒に混合することより、圧縮機２２へのオイル戻り性を確保するように構成されている。
【００４４】
また、冷媒−冷媒熱交換器２３と第２減圧装置２７を接続する高圧側の冷媒配管（主流路）３２には、冷媒−冷媒熱交換器２３出口の高圧冷媒の温度および圧力を検出するための冷媒温度センサ４１ａと高圧センサ４１ｂが設置されている。このセンサ４１ａ、４１ｂの出力信号は空調用制御装置４０に入力され、第２減圧装置２７の開度を制御することで冷媒−冷媒熱交換器２３出口の高圧冷媒のサブクール（過冷却度）を制御する。
【００４５】
また、前記したインジェクション通路２２ｄには、第１減圧装置２６で減圧された中間圧冷媒の温度および圧力を検出する中間圧冷媒温度センサ４１ｆ、中間圧センサ４１ｇが設置されている。このセンサ４１ｆ、４１ｇの出力信号は空調用制御装置４０に入力され、第１減圧装置２６の開度を制御することで、冷媒−冷媒熱交換器出口の中間圧冷媒のスーパヒート（過熱度）を制御する。
【００４６】
空調用制御装置４０はマイクロコンピュータとその周辺回路にて構成されるもので、空調用制御装置４０には、上記センサ４１ａ、４１ｂ、４１ｆ、４１ｇの他に、外気温センサ４１ｃ、蒸発器直後の空気温度を検出する蒸発器温度センサ４１ｄ、圧縮機２２の吐出ガス温度を検出する吐出温度センサ４１ｅ、室外熱交換器２４出口の冷媒温度センサ４１ｈ、インバータ３０の電流センサ４１ｉ等のセンサ群４１からセンサ信号が入力されるようになっている。
【００４７】
また、空調用制御装置４０には、空調用コントロールパネル５０（図２参照）から乗員（ユーザ）により操作される各レバーの設定状況に応じた信号も入力されるようになっている。
【００４８】
なお、図１にはインバータ３０と空調用制御装置４０との間の電気的接続のみを示し、他の機器と空調用制御装置４０との電気的接続を図示していないが、第１〜第３減圧装置２６、２７、２９、電磁弁２８ａ、２８ｂ、２８ｃ、ドア６、１６、１７、１８、図示しない吹出口切替ドア、送風機７、および室外ファン２４ａの作動も制御装置４０により制御される。電磁弁２８ａ、２８ｂ、２８ｃは、制御装置４０により後述の図８のように開閉制御されて冷媒循環経路を冷房、暖房、除湿、除霜の各運転モードに対応して切り替える。
【００４９】
一方、前記した冷媒−冷媒熱交換器２３は例えば図２に示すように、内部通路２３ａと外部通路２３ｂとを同心状に形成した二重通路構造の円筒形状になっている。内部通路２３ａは中心部に位置して室外熱交換器２４へ向かう主流の冷媒（高圧冷媒）が流れる。
【００５０】
これに対し、外部通路２３ｂは、内部通路２３ａの外周側の円周方向に並列配置された多数の小通路から形成されており、外部通路２３ｂには第１減圧装置２６で減圧された中間圧冷媒がバイパス通路６３から流入する。
【００５１】
ここで、内部通路２３ａおよび外部通路２３ｂを形成する管状体２３ｃはアルミニウム等の熱伝導性に優れた金属にて成形（例えば、押出し成形）され、かつ、管状体２３ｃの外表面には断熱材２３ｄが固着されているので、内部通路２３ａ内の高圧冷媒と外部通路２３ｂ内の中間圧冷媒との相互間のみで良好に熱交換を行うことができる。
【００５２】
この冷媒−冷媒熱交換器２３は、ガスインジェクションを必要としないときには、第１減圧装置２６を全閉することにより、内部通路２３ａのみに高圧冷媒が流れるので、高圧側配管３２の一部として使われる。
【００５３】
また、水−冷媒熱交換器７４も上記冷媒−冷媒熱交換器２３と同様に内部通路（温水通路）７４ａと外部通路（冷媒通路）７４ｂとを同心状に形成した二重通路構造の円筒形状にて構成することができる。外部通路７４ｂには冷媒−冷媒熱交換器２３の外部通路２３ｂから中間圧冷媒が配管７１を介して流入する。
【００５４】
この外部通路７４ｂの出口側は、インジェクション通路２２ｄを介してインジェクションポート２２ｃに接続されるとともに、分岐点７３ａから除霜用電磁弁２８ｃを設けた配管７２に接続される。この配管７２は第３減圧装置２９下流の分岐点７３ｂに接続されている。
【００５５】
ここで、水−冷媒熱交換器７４の内部通路（温水通路）７４ａに温水を循環させる温水回路８０について説明すると、この温水回路８０は電気自動車に搭載される発熱部品８１の冷却を行うものであって、発熱部品８１としては、例えば、電気自動車走行用交流モータ（図示せず）の回転速度制御用インバータの半導体スイッチ素子（パワートランジスタ）等である。
【００５６】
この温水回路８０には、前記した水−冷媒熱交換器７４の他に、温水循環用の電動式水ポンプ８２、電磁弁タイプの三方弁（水回路切替手段）８３、温水（冷却水）の熱を外気中に放熱する放熱器８４が備えられている。三方弁３５の切替作用により、発熱部品８１で加熱された温水が実線矢印Ａのように水−冷媒熱交換器７４側に流れるか、または破線矢印Ｂのように放熱器８４側に流れるようになっている。
【００５７】
次に、図３に示す空調コントロールパネル５０には、乗員により手動操作される以下の操作部材が設けられている。５１は車室内への吹出空気の温度の目標値を設定する温度コントロールレバーで、本例では、電動式圧縮機２２の回転数調整の目標値を設定するように構成されている。
【００５８】
また、温度コントロールレバー５１の操作位置により設定される目標値に対し、電磁弁２８ａ、２８ｂ、２８ｃおよび通路切替ドア１６、１７の開閉を制御し、冷凍サイクルの運転モードを切り替える。
【００５９】
各運転モードの切替は例えば図４に示すようにレバー５１を左から右に移動させることにより冷房モード、除湿モード、暖房モードを順次設定する。また、図５、６、７に示すように温度コントロールレバー５１の操作位置の移動により、冷房時には目標蒸発器吹出温度が設定され、除湿時および暖房時には目標高圧圧力が設定されるようになっている。
【００６０】
温度コントロールレバー５１の操作位置信号は制御装置４０に入力され、そして制御装置４０は、センサ群４１により検出される実際の蒸発器吹出空気温度または高圧圧力が上記目標値と一致するように圧縮機２２の回転数を制御して、吹出空気温度を制御する。
【００６１】
５２は送風機７の速度（風量）切替レバー、５３は圧縮機２２の運転を断続するエアコンスイッチ、５４は吹出口８、９、１０の切替ドア（図示せず）を開閉する空調吹出モード切替レバー、５５は内外切替ドア６を開閉する内外気切替レバーである。
【００６２】
次に、上記構成において第１実施形態の作動を説明する。エアコンスイッチ５３が投入されると、その信号が制御装置４０に投入され、圧縮機２２を起動する。この状態にて温度コントロールレバー５１が図４のＰＨ２からＰＨ１の位置にあると、制御装置４０は暖房モードと判定して電磁弁２８ａ、２８ｂ、２８ｃ、通路切替ドア１６、１７等の機器を図８の暖房モード時の状態に制御する。
【００６３】
図１の黒色矢印は暖房モード時における冷媒流れを示し、図９は暖房モード時における冷凍サイクルの冷媒の状態を示すモリエル線図である。圧縮機２２から吐出された高温高圧の過熱ガス冷媒は、まず、室内に設定された凝縮器１２に流入し、ここで送風機７により送風される空気と熱交換（放熱）し、ガス冷媒が凝縮する。ガス冷媒の凝縮により加熱された温風は主にフット吹出口８より車室内へ吹き出され、車室内の暖房を行う。
【００６４】
凝縮器１２から流出した高圧冷媒の一部は、冷房用電磁弁２８ｂが閉じているため、分岐点６１ａからバイパス通路６３側へ分岐される。そして、この分岐された高圧冷媒は第１減圧装置２６に流入し、中間圧ＰＭまで減圧される。中間圧ＰＭまで減圧された二相冷媒は冷媒−冷媒熱交換器２３の外部通路２３ｂを通り、内部通路２３ａを通る室内凝縮器１２出口の高圧冷媒と熱交換（吸熱）することで乾き度が増加する。
【００６５】
暖房モード時には温水回路８０の発熱部品８１にて加熱された温水が三方弁８３により実線矢印Ａのように水−冷媒熱交換器７４側に流れるので、冷媒−冷媒熱交換器２３の外部通路２３ｂから流出した中間圧冷媒は水−冷媒熱交換器７４において温水と熱交換（吸熱）することで乾き度が増加してガス化する。
【００６６】
電磁弁２８ｃは暖房モード時に閉状態にあるので、中間圧のガス冷媒はインジェクション通路２２ｄを通ってインジェクションポート２２ｃに流入する。
【００６７】
一方、冷媒−冷媒熱交換器２３の内部通路２３ａを通る高圧冷媒は外部通路２３ｂを通る冷媒と熱交換（放熱）し、過冷却される。この過冷却された高圧冷媒は第２減圧装置２７に流入し、第２減圧装置２７により低圧ＰＬまで減圧され室外熱交換器２４に流入する。そして、この低圧冷媒が室外熱交換器２４を通る際に室外ファン２４ａの送風空気（外気）から吸熱して蒸発する。
【００６８】
室外熱交換器２４で蒸発したガス冷媒は、開状態にある暖房用電磁弁２８ａを通過してアキュムレータ２５に流入し、暖房負荷の変動により生じる液冷媒はアキュムレータ２５内に溜められる。アキュムレータ２５ではそのＵ状の冷媒出口管２５ａの上端開口部からガス冷媒を吸入するとともに、Ｕ状の冷媒出口管２５ａの底部に設けたオイル戻し穴（図示せず）から、オイルが溶け込んだ液冷媒を吸入してガス冷媒に混合し、このガス冷媒を圧縮機２２の吸入ポート２２ｂに吸入させる。これにより、中間期の暖房低負荷時のように冷媒流量が少ない条件のもとでも、圧縮機２２へ確実にオイルを戻すことができる。
【００６９】
第１減圧装置（電気式膨張弁）２６の開度は、中間圧冷媒の温度センサ４１ｆおよび圧力センサ４１ｇの検出信号に基づいて制御装置４０により制御されて、圧縮機２２のインジェクションポート２２ｃに流入するガスインジェクション冷媒のスーパーヒートＳＨが所定量になるように冷媒流量を制御する。すなわち、ガスインジェクション冷媒のスーパーヒートＳＨが大きくなれば、第１減圧装置（電気式膨張弁）２６の開度を増大し、逆にスーパーヒートＳＨが小さくなれば、第１減圧装置（電気式膨張弁）２６の開度を減少させる。このようなガスインジェクション冷媒のスーパーヒート制御により圧縮機２２への過度な液戻りを防止できる。
【００７０】
また、第２減圧装置２７の開度は制御装置４０により制御されて、冷媒−冷媒熱交換器２３の内部通路２３ａを出た高圧冷媒のサブクールＳＣが所定量になるように冷媒−冷媒熱交換器２３での交換熱量を制御する。すなわち、高圧冷媒のサブクールＳＣが大きくなれば、第２減圧装置２７の開度を増大して高圧を低下させてサブクールＳＣを減少させる。逆に、高圧冷媒のサブクールＳＣが小さくなれば、第２減圧装置２７の開度を減少して高圧を上昇させて、サブクールＳＣを増加させる。
【００７１】
なお、図９において、Ｇｉはインジェクション通路２２ｄからインジェクションポート２２ｃにガスインジェクションされる冷媒流量、Ｇｅは室外熱交換器（暖房時の蒸発器）２４を通して圧縮機２２に吸入される冷媒流量、Δｉ₁は冷媒−冷媒熱交換器２３および水−冷媒熱交換器７４で吸熱するガスインジェクション側の中間圧冷媒のエンタルピ差で、Δｉ₂は冷媒−冷媒熱交換器２３で放熱して、第２減圧装置２７に向かう高圧冷媒のエンタルピ差である。
【００７２】
また、通路切替ドア１６、１７は凝縮器１２側の空気通路を開いてバイパス通路１２ａを全閉するので、圧縮機２２から吐出された高温高圧冷媒と送風機７により送風された空気とを凝縮器１２にて熱交換させる。
【００７３】
図１０は第１減圧装置２６により減圧された中間圧冷媒の圧力（中間圧）を横軸にとり、縦軸にインジェクション冷媒のスーパーヒートＳＨおよび暖房能力Ｑｃをとったもので、スーパーヒートＳＨが所定値Ｔ１であるときに、水−冷媒熱交換器７４での廃熱回収がないときは中間圧＝Ｐｍとなり、そのときの暖房能力ＱｃはＱ１となる。
【００７４】
これに対し、本実施形態のように、水−冷媒熱交換器７４で温水から廃熱回収を行うときは、スーパーヒートＳＨを同じ値Ｔ１に制御しても、温水からの廃熱回収により中間圧冷媒のガス化が促進されるので、図１１に示すように中間圧をＰｍからＰｍ１まで高めることができる。この中間圧の上昇により、ガスインジェクション冷媒流量がＧｉからＧｉ１に増加して、暖房能力Ｑｃを図１０のＱ１からＱ２に向上できる。図１１は廃熱回収の有無によるサイクル冷媒状態の変化を示すモリエル線図である。
【００７５】
次に、暖房モード時における除霜モードについて説明する。暖房モード時では蒸発器として作用する室外熱交換器２４において発生する凝縮水が凍結して、室外熱交換器２４に着霜状態が生じる。この室外熱交換器２４の着霜状態が制御装置４０により判定されると、電磁弁２８ａ、２８ｂ、２８ｃ、通路切替ドア１６、１７等の機器が図８の除霜モード時の状態に切り替えられる。
【００７６】
室外熱交換器２４の着霜状態は種々な方法で判定することができるが、本例では、室外熱交換器２４の着霜により室外熱交換器２４の出口冷媒温度Ｔｈｏが低下して、外気温Ｔａｍとこの出口冷媒温度Ｔｈｏとの差（Ｔａｍ−Ｔｈｏ）が所定値（例えば、２０°Ｃ）より大きくなると、室外熱交換器２４が着霜状態であるとしてサイクルを図１２の除霜モード状態に切り替える。
【００７７】
図１２の矢印は除霜モードにおける冷媒の流れ方向を示し、図１３は除霜モードにおける冷媒の状態変化を示すモリエル線図である。
【００７８】
除霜モード時には、通路切替ドア１６、１７により凝縮器１２の空気通路が全閉されているので、送風機７の送風空気はすべて凝縮器１２のバイパス通路１２ａを通過する。そのため、圧縮機２２からの吐出ガス冷媒は凝縮器１２で熱交換せずに吐出直後の状態のまま凝縮器１２を通過し、分岐点６１ａにて２つの流れに分岐される。
【００７９】
すなわち、一方の冷媒流れは冷媒−冷媒熱交換器２３の内部通路２３ａを通って放熱した後に、第２減圧装置２７により減圧され室外熱交換器２４に流入する。ここで、減圧後のガス冷媒（ホットガス）が室外熱交換器２４にて放熱して、室外熱交換器２４の霜を溶かす。室外熱交換器２４を通過した冷媒は開状態にある暖房用電磁弁２８ａを通過してアキュムレータ２５に流入する。
【００８０】
分岐点６１ａからの他方の冷媒流れは、第１減圧装置２６に流入し、減圧される。この減圧後のガス冷媒は冷媒−冷媒熱交換器２３の外部通路２３ｂを通り、内部通路２３ａを通る高圧ガス冷媒と熱交換して吸熱した後に、水−冷媒熱交換器７４の外部通路（冷媒通路）７４ｂにて温水から再度吸熱する。
【００８１】
その後に、ガス冷媒は除霜用電磁弁２８ｃを通過して室内蒸発器１１に流入し、送風機７の送風空気中に放熱する。室内蒸発器１１を通過した冷媒は、アキュムレータ２５に流入し、室外熱交換器２４を通過した冷媒と合流し、圧縮機２２に吸入される。
【００８２】
室内蒸発器１１にて加熱された送風空気（温風）は凝縮器１２のバイパス通路１２ａを通過して主にフット吹出口８から車室内へ吹き出し、車室内の暖房を行う。従って、除霜中にも車室内の暖房を続行できるので、除霜中における車室内温度の低下を抑制できる。なお、除霜モード時には第１、第２減圧装置２６、２７は予め設定された所定の制御開度に保持される。
【００８３】
除霜モードが進行して、室外熱交換器２４の出口冷媒温度Ｔｈｏが上昇して外気温Ｔａｍとこの出口冷媒温度Ｔｈｏとの差（Ｔａｍ−Ｔｈｏ）が所定値（例えば、２０°Ｃ）以下になり、かつ、その状態が所定時間（例えば、１０秒）以上継続されると、室外熱交換器２４の除霜が終了したと判定し、自動的に暖房モードに復帰させる。
【００８４】
次に、温度コントロールレバー５１が図３のＰＣ１からＰＣ２の位置にあると、制御装置４０は冷房モードと判定して電磁弁２８ａ、２８ｂ、２８ｃ、通路切替ドア１６、１７等の機器を図８の冷房モードの状態に制御する。図１の白抜き矢印は冷房モードにおける冷媒流れを示す。
【００８５】
冷房モード時には、通路切替ドア１６、１７が凝縮器１２側の空気通路を全閉するため、送風機７の送風空気は全量、バイパス通路１２ａを流れる。そのため、圧縮機２２から吐出された高温高圧の過熱ガス冷媒は、凝縮器１２で送風機７の送風空気と熱交換（放熱）せず、それ故、圧縮機２２からの吐出直後の過熱状態のまま、凝縮器１２を通過する。
【００８６】
このとき、第１、第２減圧装置（電気式膨張弁）２６、２７が全閉状態に制御されているため、圧縮機２２からの吐出ガス冷媒の全量が、開弁状態にある冷房用電磁弁２８ｂおよびバイパス通路６２を通って室外熱交換器２４に流入する。
【００８７】
この室外熱交換器２４では、高圧ガス冷媒が室外ファン２４ａの送風空気（外気）と熱交換（放熱）して凝縮する。そして、室外熱交換器２４で凝縮した冷媒は、電磁弁２８ａ、２８ｃの閉弁により第３減圧装置２９を通過して低圧ＰＬまで減圧された後、蒸発器１１に流入する。ここで、第３減圧装置２９は高圧センサ４１ｂと室外熱交換器２４の出口冷媒温度センサ４１ｈの検出信号に基づいて室外熱交換器２４出口冷媒のサブクールが所定値となるように弁開度が制御される。
【００８８】
蒸発器１１にて冷媒が送風機７の送風空気から吸熱して蒸発し、蒸発器１１にて冷却された冷風は、上記したように下流側の室内凝縮器１２は通過せず、そのバイパス通路１２ａを冷風のまま通過して、主にフェイス吹出口９から車室内へ吹き出して車室内を冷房する。
【００８９】
一方、蒸発器１１で蒸発したガス冷媒はアキュムレータ２５に流入し、このアキュムレータ２５からガス冷媒は圧縮機２２の吸入ポート２２ｂに吸入される。
【００９０】
次に、温度コントロールレバー５１が図３のＰＤ１からＰＤ２の位置にあると、制御装置４０は除湿モードと判定して電磁弁２８ａ、２８ｂ、２８ｃ、通路切替ドア１６、１７等の機器を図８の除湿モード時の状態に制御する。図１の斜線付き矢印は除湿モード時の冷媒流れ経路を示す。
【００９１】
除湿モード時には、通路切替ドア１６、１７により凝縮器１２の空気通路が開放されるので、圧縮機２２から吐出された高温高圧の過熱ガス冷媒は凝縮器１２に流入し、ここで送風機７の送風空気と熱交換（放熱）し、ガス冷媒が凝縮する。
【００９２】
このとき、第１減圧装置２６および冷房用電磁弁２８ｂが全閉されているので、凝縮器１２で凝縮した高圧冷媒の全量が冷媒−冷媒熱交換器２３の内部通路２３ａを通過する。このとき、内部通路２３ａを通過する冷媒は冷却されず、室内凝縮器１２を出たときの状態のまま、冷媒−冷媒熱交換器２３を通過して第２減圧装置２７に流入し、この第２減圧装置２７により中間圧に減圧され室外熱交換器２４に流入する。
【００９３】
ここで、第２減圧装置２７により作られる中間圧は、除湿モードにおいて高い吹出温度が必要な第１除湿モードＤ₁では、外気温度に対する冷媒の飽和圧力より低く設定することにより、室外熱交換器２４を蒸発器として作用させて吸熱側に設定できる。すなわち、第２減圧装置２７の開度を小さくして減圧量を大きくすることにより中間圧が低く設定される。
【００９４】
そして、室外熱交換器２４を流れ出た中間圧冷媒は、暖房用電磁弁２８ａの閉弁により第３減圧装置２９に流入し、低圧ＰＬまで減圧される。この減圧された低圧冷媒は蒸発器１１に流入し、送風機７の送風空気から吸熱して蒸発した後、アキュムレータ２５に流入する。アキュムレータ２５からガス冷媒は圧縮機２２の吸入ポート２２ｂに吸入される。
【００９５】
除湿モードでは、室内空調ユニット１内に設定された蒸発器１１および凝縮器１２にともに冷媒が流れて、送風機７の送風空気はまず蒸発器１１で冷却、除湿され、その後に凝縮器１２にて再加熱され、温風となる。この温風は主にデフ吹出口１０より車室内へ吹き出され、窓ガラスの曇り止めを行うとともに、車室内を除湿暖房する。
【００９６】
ところで、除湿モードの中で、高い吹出温度が必要な第１除湿モードＤ₁では、圧縮機２２の動力、室外熱交換器２４の吸熱量、および室内蒸発器１１での吸熱量の総和を室内凝縮器１２から放熱できるため、目的とする高い吹出温度を作り出すことができる。
【００９７】
一方、除湿モードの中で、低い吹出温度が必要な第２除湿モードＤ₂では、第２減圧装置２７により作られる中間圧を、外気温度に対する冷媒の飽和圧力よりも高く設定することにより、室外熱交換器２４を凝縮器として作用させて放熱側に設定できる。すなわち、第２減圧装置２７の弁開度を大きくして減圧量を小さくすることにより中間圧が高く設定される。
【００９８】
これにより、室外熱交換器２４が凝縮器となり放熱側として作用するため、圧縮機２２の動力Ｌおよび室内蒸発器１１での吸熱量の合計と、室外熱交換器２４での放熱量Ｑｅｈと室内凝縮器１１での放熱量Ｑｃの合計とが等しくなる。従って、室内凝縮器１１での放熱量は第１除湿モードＤ₁の場合より減少するので、目的とする低い吹出温度を作り出すことができる。
【００９９】
なお、本第１実施形態によると、以下の理由からサイクル冷媒循環経路を簡素化できる。すなわち、除霜モードおよび冷房モード時においても、通路切替ドア１６、１７により凝縮器１２への空気流れを遮断してバイパス通路１２ａを空気が通過するようにしているため、凝縮器１２は高圧冷媒が流れる冷媒通路の一部となる。そのため、暖房、冷房、除湿および除霜の全モードを通じて、凝縮器１２に冷媒が流れたままとなるので、圧縮機２２の吐出ガス冷媒を常に凝縮器１２を通して室外熱交換器２４等へ向かう一方向に流すことができる。その結果、冷媒流れ方向逆転のための四方弁の廃止、あるいは、冷媒流れ経路切替用の逆止弁、電磁弁等の弁装置の数を低減することが可能となり、冷媒配管構成を簡素化できる。
【０１００】
（第２実施形態）
図１４は第２実施形態であり、第１実施形態では温水回路８０に三方弁８３を設けて、暖房、除霜モード時には発熱部品８１で加熱された温水を実線矢印Ａのように水−冷媒熱交換器７４側に流し、また、冷房、除湿モード時には発熱部品８１で加熱された温水を破線矢印Ｂのように放熱器８４側に流すようにしているが、第２実施形態では三方弁８３、放熱器８４を廃止して、常に水−冷媒熱交換器７４に温水が流れるようにしている。
【０１０１】
第２実施形態によると、放熱器８４の廃止に伴って発熱部品８１の冷却を常に水−冷媒熱交換器７４にて行う必要が生じる。従って、インジェクション通路２２ｄ側に常に冷媒を循環することになり、冷房モード時にインジェクション冷媒の温度上昇により圧縮機吐出冷媒温度が上昇するものの、温水回路８０の部品点数低減によるコスト低減を図ることができる。
【０１０２】
（第３実施形態）
図１５は第３実施形態であり、第１実施形態では水−冷媒熱交換器７４を中間圧冷媒が流れるインジェクション通路２２ｄ側に設けて、インジェクション冷媒により発熱部品８１の廃熱回収を行っているが、第３実施形態では低圧側冷媒により発熱部品８１の廃熱回収を行うようにしている。
【０１０３】
すなわち、図１５に示すように、蒸発器１１の出口側と暖房用電磁弁２８ａの出口側との合流点７３ｃと、アキュムレータ２５の入口部との間に水−冷媒熱交換器７４を設けている。
【０１０４】
第３実施形態によると、冷房時に蒸発器１１出口からの冷媒が水−冷媒熱交換器７４の外部通路（冷媒通路）７４ｂを通って流れるので、圧損増加による若干の効率低下が生じるとともに、暖房モード時に廃熱回収によるインジェクション冷媒の増量効果を発揮できないが、その代わりに、第３実施形態においては温水回路８０の温水温度が低い条件の時にも、温水からの廃熱回収を行って暖房能力を向上できる。
【０１０５】
すなわち、図１６は第３実施形態による除霜モード時のモリエル線図（図１３に対応）であり、水−冷媒熱交換器７４の外部通路（冷媒通路）７４ｂではアキュムレータ２５入口側の気液２相域の低圧冷媒が流れる。この気液２相域の低圧冷媒の温度は過熱ガス域の冷媒より十分低い温度であるので、温水回路８０の温水温度が多少低くくなっても温水と冷媒との温度差を確保して、温水からの廃熱回収による暖房能力向上を実現できる。この効果は、除霜モード時だけでなく、暖房モード時にも同様に発揮できる。
【０１０６】
なお、図１３、１６では、図面作成上の理由から蒸発器１１での冷媒圧力を室外熱交換器２４での冷媒圧力より低い状態で図示しているが、実際は両者１１、２４での冷媒圧力が同等であることはもちろんである。
【０１０７】
（第４実施形態）
図１７は第４実施形態であり、第１〜第３実施形態では水−冷媒熱交換器（第１熱交換手段）７４と冷媒−冷媒熱交換器（第２熱交換手段）２３とをそれぞれ独立に構成しているが、第４実施形態では図１７〜図１９に示すように、両熱交換器２３、７４を１つの一体型熱交換器２３０として構成している。
【０１０８】
図１８、１９により、一体型熱交換器２３０の具体例を説明すると、冷媒−冷媒熱交換器２３における高圧冷媒が流れる内部通路２３ａに相当する高圧冷媒通路部２３０ａと、冷媒−冷媒熱交換器２３における中間圧冷媒が流れる外部通路２３ｂに相当する中間圧冷媒通路部２３０ｂと、水−冷媒熱交換器７４における温水が流れる内部通路７４ａに相当する温水通路部２３０ｃとを一体化している。
【０１０９】
この一体化に際して、上記三者の通路部２３０ａ〜２３０ｃをいずれもアルミニュウム等の金属により押し出し加工された扁平状の多穴チューブにより構成するとともに、中間圧冷媒通路部２３０ｂを中央にして、その両側に高圧冷媒通路部２３０ａと温水通路部２３０ｃとを密着接合して一体化している。
【０１１０】
（他の実施形態）
なお、上記した第１〜第４実施形態では、凝縮器１２の出口側（冷媒−冷媒熱交換器２３の上流側）の分岐点６１ａと、室外熱交換器２４の入口側（第２減圧装置２７の下流側）の合流点６１ｂとを直接結合するバイパス通路６２を設け、このバイパス通路６０に電磁弁（電気的開閉手段）２８ｂを挿入しているが、バイパス通路６２を廃止して電磁弁２８ｂを第２減圧装置２７の入口、出口間に直接並列接続してもよい。
【０１１１】
上述の各実施形態では、凝縮器１２への空気流れとバイパス通路１２ａへの空気流れを切り替えるドア手段として、連動操作される２枚の板状の通路切替ドア１６、１７を用いているが、このドア手段として、１枚の板状ドア、さらにはフィルム状ドア等を用いてもよい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実施形態を示す冷凍サイクル図である。
【図２】第１実施形態で使用する冷媒−冷媒熱交換器の具体例を示す断面図である。
【図３】第１実施形態で使用する空調制御パネルの正面図である。
【図４】図３の空調制御パネルにおける温度コントロールレバーの作動領域と運転モードとの特性図である。
【図５】同温度コントロールレバーの冷房領域の特性図である。
【図６】同温度コントロールレバーの除湿領域の特性図である。
【図７】同温度コントロールレバーの暖房領域の特性図である。
【図８】第１実施形態で使用する弁・ドアの作動説明用の図表である。
【図９】第１実施形態における暖房モードの冷凍サイクルの作動を説明するモリエル線図である。
【図１０】第１実施形態における廃熱回収有無による暖房能力の説明図である。
【図１１】第１実施形態における廃熱回収有無による冷凍サイクルの作動の違いを説明するモリエル線図である。
【図１２】第１実施形態における除霜時の作動を説明する冷凍サイクル図である。
【図１３】第１実施形態における除霜時の作動を説明するモリエル線図である。
【図１４】本発明の第２実施形態を示す冷凍サイクル図である。
【図１５】本発明の第３実施形態を示す冷凍サイクル図である。
【図１６】第３実施形態における除霜時の作動を説明するモリエル線図である。
【図１７】第４実施形態を示す冷凍サイクル図である。
【図１８】第４実施形態による一体型熱交換器を例示する概略斜視図である。
【図１９】図１８の各通路接合部の断面図である。
【符号の説明】
１１…蒸発器、１２…凝縮器、１６、１７…通路切替ドア、２２…圧縮機、
２２ｃ…ガスインジェクションポート、２２ｄ…ガスインジェクション用通路、２３…冷媒−冷媒熱交換器、２４…室外熱交換器、２５…アキュムレータ、
２６…第１減圧装置、２７…第２減圧装置、２９…第３減圧装置、
７４…水−冷媒熱交換器、８１…発熱部品。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat pump type refrigeration cycle apparatus capable of switching between a heating mode, a cooling mode, and a dehumidifying mode, and is suitable for use in, for example, an air conditioner for an electric vehicle.
[0002]
[Prior art]
Conventionally, in a vehicle such as an electric vehicle, the vehicle interior cannot be heated using engine waste heat (hot water) as a heat source. Therefore, a heat pump type refrigeration cycle device is provided and the vehicle interior is heated by the refrigerant condensation heat in the condenser. Like to heat up.
[0003]
However, in a usage environment in which the outside air temperature drops below -10 ° C as in cold weather in winter, the amount of heat absorbed by the outdoor heat exchanger acting as an evaporator in the heat pump cycle is reduced, and the compressor suction Since the pressure is reduced, the refrigerant specific volume is increased, and the amount of refrigerant circulation is reduced, so that there is a problem that the heating capacity is lowered. For this reason, when used in cold regions, the heating capacity in the passenger compartment is insufficient.
[0004]
Therefore, in the present applicant, first, in JP-A-9-328013, during heating, the cycle high-pressure refrigerant is reduced to an intermediate pressure, and this intermediate-pressure refrigerant is separated into a gas refrigerant and a liquid refrigerant by a gas-liquid separator. And proposed a refrigeration cycle device that increases the heating capacity by increasing the amount of compression work of the compressor during heating by gas-injecting the intermediate-pressure gas refrigerant into the compressor. Yes.
[0005]
In this prior art, the evaporator of the refrigeration cycle is arranged upstream of the air passage of the indoor air conditioning unit, and the condenser of the refrigeration cycle is arranged downstream of the air passage, so that the dehumidifying operation is performed. I try to stop fogging.
[0006]
Further, in the above prior art, the four-way valve arranged on the discharge side of the compressor allows the discharge gas of the compressor to flow into the outdoor heat exchanger during cooling, and the discharge gas of the compressor to the indoor condenser during heating. The flow direction of the refrigerant is switched so as to flow in.
[0007]
[Problems to be solved by the invention]
By the way, in the above prior art, when frost is generated in the outdoor heat exchanger during heating, the refrigerant flow is reversed by a four-way valve to make a reverse cycle (cooling cycle), and the frost in the outdoor heat exchanger is removed from the compressor. The heat is removed by the heat of the high temperature discharge gas.
[0008]
Thus, since the defrosting of the outdoor heat exchanger is performed by reversing to the reverse cycle, the room heating cannot be performed during the defrosting, and the heating feeling is impaired.
[0009]
In the above-described conventional technology, the cooling flow is switched by the four-way valve to switch the operation mode. Therefore, the refrigerant piping configuration of the cycle becomes complicated, and the number of parts such as a check valve increases.
[0010]
In view of the above points, the present invention firstly aims to ensure an indoor heating function in a defrosting mode of an outdoor heat exchanger.
[0011]
A second object of the present invention is to achieve both the improvement of the heating capacity during normal heating and the securing of the indoor heating function during defrosting of the outdoor heat exchanger.
[0012]
A third object of the present invention is to simplify the refrigerant passage configuration of the cycle.
[0013]
[Means for Solving the Problems]
  In order to achieve the above object, the invention according to claim 1 provides:An air conditioning passage (2) through which air flows into the room;
  A compressor (22) for compressing and discharging the refrigerant;
  A condenser (12) that is installed in the air conditioning passage (2) and that heats the air with a refrigerant gas discharged from the compressor (22);
  A bypass passage (12a) that is formed in the air conditioning passage (2) and flows the air bypassing the condenser (12);
  Door means (16, 17) installed in the air conditioning passage (2), for switching between an air flow to the condenser (12) and an air flow to the bypass passage (12a);
  An outdoor heat exchanger (24) installed outdoors;
  A heating decompressor (27) installed on the refrigerant inlet side of the outdoor heat exchanger (24);
  Installed upstream of the condenser (12) in the air conditioning passage (2).TheAn evaporator (11);
  A cooling decompression device (29) installed on the refrigerant inlet side of the evaporator (11);
  A refrigerant bypass passage (63) through which the refrigerant flows by bypassing the heating decompression device (27);
  A bypass-side pressure reducing device (26) provided in the refrigerant bypass passage (63);With
  The discharge side of the compressor (22) is always connected to the condenser (12), and the discharge gas refrigerant from the compressor (22) always passes through the condenser (12) and the outdoor heat exchanger. (24) to flow in one direction to the side,
  In the heating mode, the discharge gas refrigerant of the compressor (22) is changed by switching the door means (16, 17) to a position where the blown air in the air conditioning passage (2) passes through the condenser (12). The refrigerant is condensed by flowing into the condenser (12) and dissipating heat to the blown air in the air conditioning passage (2), and the high-pressure refrigerant after passing through the condenser (12) is decompressed by the heating decompression device (27). The low-pressure refrigerant after passing through the heating decompression device (27) flows into the outdoor heat exchanger (24) and evaporates, and the low-pressure refrigerant after passing through the outdoor heat exchanger (24) It is designed to be sucked into the compressor (22), and in the heating modeHot air heated by the condenser (12) is blown into the roomAnd
  In the cooling mode, by switching the door means (16, 17) to a position where the blown air in the air conditioning passage (2) passes through the bypass passage (12a), the discharge gas refrigerant of the compressor (22) is changed. The outdoor heat exchanger (24) passes through the condenser (12) without exchanging heat with the blown air in the air conditioning passage (2), and the discharged gas refrigerant after passing through the condenser (12) remains in a high pressure state. And the discharge gas refrigerant condenses in the outdoor heat exchanger (24), and the high-pressure refrigerant after passing through the outdoor heat exchanger (24) is decompressed by the cooling decompression device (29) to be in a low pressure state. Then, the low-pressure refrigerant after passing through the cooling decompression device (29) flows into the evaporator (11) and absorbs heat from the blown air in the air-conditioning passage (2) to evaporate, and the evaporator (11) The low-pressure refrigerant after passing is compressed (22) is adapted to be inhaled, in the cooling modeCold air cooled by the evaporator (11)Through the bypass passage (12a)Blowing into the roomAnd
  In the dehumidifying mode, the discharge gas refrigerant of the compressor (22) is changed by switching the door means (16, 17) to a position where the blown air in the air conditioning passage (2) passes through the condenser (12). The refrigerant is condensed by flowing into the condenser (12) and dissipating heat to the blown air in the air conditioning passage (2), and the high-pressure refrigerant after passing through the condenser (12) is decompressed by the heating decompression device (27). The intermediate-pressure refrigerant after passing through the heating pressure reducing device (27) flows into the outdoor heat exchanger (24) and exchanges heat with outdoor air, and passes through the outdoor heat exchanger (24). The subsequent intermediate pressure refrigerant is decompressed by the cooling decompression device (29) to be in a low pressure state, and the low pressure refrigerant after passing through the cooling decompression device (29) flows into the evaporator (11) and enters the air conditioning passage ( 2) To absorb heat from the blown air inside Evaporated, the evaporator (11) low-pressure refrigerant after passing through said pressure It is designed to be sucked into the compressor (22), and in the dehumidification modeThe cold air cooled and dehumidified by the evaporator (11) is reheated by the condenser (12) and blown into the room.And
  When setting the defrost mode for defrosting the outdoor heat exchanger (24) during the heating mode,By switching the door means (16, 17) to a position where the blown air in the air conditioning passage (2) passes through the bypass passage (12a), the discharged gas refrigerant of the compressor (22) is changed to the air conditioning passage ( 2) Passing through the condenser (12) without exchanging heat with the blown air inside, and discharging after passing through the condenser (12)Gas refrigerant,The flow toward the heating decompression device (27) and the flow toward the refrigerant bypass passage (63)Branch,
  One of the branched gas refrigerantsIs reduced in pressure by the heating decompression device (27) to be in a low pressure state, and the low-pressure gas refrigerant after passing through the heating decompression device (27)Inflow into the outdoor heat exchanger (24)do itDefrosting the outdoor heat exchanger (24),The low-pressure refrigerant after passing through the outdoor heat exchanger (24) is sucked into the compressor (22),
  Also,The other of the branched gas refrigerant isThe refrigerant flows into the refrigerant bypass passage (63) and is depressurized by the bypass side pressure reducing device (26) to be in a low pressure state, and the low pressure gas refrigerant after passing through the bypass side pressure reducing device (26)It flows into the evaporator (11), and the blower air in the air conditioning passage (2) is blown by the evaporator (11).By the low-pressure gas refrigerantHeated,The low-pressure refrigerant after passing through the evaporator (11) is also sucked into the compressor (22), and in the defrosting mode, the warm air heated by the evaporator (11) Blows into the room through (12a)It is characterized by that.
[0014]
According to this, while performing defrosting of the outdoor heat exchanger (24), indoor heating can be continued by the air heating action of the evaporator (11) at the same time. That is, paying attention to the point that the evaporator (11) is not used in the heating mode, in the present invention, the evaporator (11) is effectively used in the defrosting mode, so that the defrosting mode is not caused without complicating the cycle. It is possible to ensure the indoor heating action in the.
[0015]
  In the first aspect of the present invention, in the cooling and defrosting mode, the air flow to the condenser (12) is blocked by the door means (16, 17) and the air is allowed to pass through the bypass passage (12a). Therefore, the condenser (12) serves as a part of the refrigerant passage through which the high-pressure refrigerant flows.
  Therefore, through each mode of heating, cooling, dehumidification, and defrosting, the refrigerant remains flowing into the condenser (12), and the discharge gas refrigerant of the compressor (22) is always passed through the condenser (12) to the outdoor heat exchanger ( 24). As a result, it is possible to eliminate the four-way valve for reversing the refrigerant flow direction, or to reduce the number of valve devices such as a check valve and a solenoid valve for switching the refrigerant flow path, thereby simplifying the refrigerant piping configuration. Product cost can be reduced.
  Next, in the invention according to claim 2, in claim 1, it has the 1st heat exchange means (74, 320) which collects the waste heat of exothermic parts (81),
  During defrost mode,The low-pressure gas refrigerant decompressed by the bypass-side decompression device (26)Waste heat of the heat generating component (81) is removed by the first heat exchange means (74, 320).The gas refrigerant in the low pressure state after absorbing heat and absorbing this waste heatEvaporator (11)InInflowDoIt is characterized by that.
[0016]
According to this, the room heating capability by the evaporator (11) at the time of a defrost mode can be improved by the waste heat recovery of a heat-emitting component (81).
[0017]
  Next, in the invention of claim 3, in claim 2, as the compressor (22), a discharge port (22a) for discharging the compressed refrigerant, a suction port (22b) for sucking in the refrigerant on the low pressure side of the refrigeration cycle, And a compressor having a gas injection port (22c) for introducing a gas refrigerant on the refrigeration cycle intermediate pressure side,
  Even in the heating mode, the high-pressure refrigerant condensed in the condenser (12) branches into a flow toward the heating decompression device (27) and a flow toward the refrigerant bypass passage (63),
  One of the branched refrigerants is decompressed by the heating decompression device (27) to become a low pressure state and flows into the outdoor heat exchanger (24),
  The other of the branch refrigerant is by a bypass side pressure reducing device (26).The intermediate pressure refrigerant is depressurized to an intermediate pressure, the first heat exchange means (74, 320) absorbs the waste heat of the heat generating component (81), the intermediate pressure refrigerant is gasified, and the intermediate pressure gas refrigerant is gasified. Flow into the injection port (22c)And
  In the heating mode, the low-pressure refrigerant after passing through the outdoor heat exchanger (24) is sucked into the suction port (22b), and in the cooling mode, the low-pressure refrigerant after passing through the evaporator (11) is sucked into the suction port (22b), In the defrosting mode, the low-pressure refrigerant after passing through the outdoor heat exchanger (24) and the low-pressure refrigerant after passing through the evaporator (11) are sucked into the suction port (22b).It is characterized by that.
[0018]
According to this, the improvement effect of the heating capability by the gas injection to the compressor (22) and the improvement effect of the heating capability by the waste heat recovery of the heat generating component (81) can be combined. Therefore, it is possible to satisfactorily balance the improvement of the heating capacity during normal heating and the securing of the indoor heating action during the defrosting of the outdoor heat exchanger.
[0019]
  Next, in invention of Claim 4, in Claim 3, at the time of heating mode,It is said one branch refrigerant which goes to decompression device (27) for heatingHigh-pressure refrigerant,The pressure was reduced by the bypass side pressure reducing device (26).It has the 2nd heat exchange means (23,230) which heat-exchanges with an intermediate pressure refrigerant | coolant, It is characterized by the above-mentioned.
[0020]
According to this, since the intermediate pressure refrigerant absorbs heat from the high pressure refrigerant and also absorbs heat from the waste heat of the heat generating component (81), gasification of the intermediate pressure refrigerant is promoted, and the heating capacity can be effectively improved.
[0021]
Next, the invention described in claim 5 is characterized in that, in claim 4, the first heat exchange means and the second heat exchange means are integrally formed as one heat exchanger (230).
[0022]
According to this, the first and second heat exchanging means can be made compact and simple by the integrated heat exchanger (230).
[0023]
  Next, in invention of Claim 6, in Claim 1, it has the 1st heat exchange means (74, 320) which collect | recovers the waste heats of a heat-emitting component (81),
  Inhaled into compressor (22) during heating mode, After passing the outdoor heat exchanger (24)The low-pressure refrigerant absorbs the waste heat of the heat generating component (81) by the first heat exchange means (74, 320),
  During defrost modeIsSucked into the compressor (22), After passing the outdoor heat exchanger (24)Low pressure refrigerant and sucked into compressor (22), After passing through the evaporator (11)The waste heat of the heat generating component (81) is absorbed into the low-pressure refrigerant by the first heat exchange means (74, 320).
[0024]
According to this, since the temperature of the low-pressure side refrigerant is lower than that of the intermediate-pressure refrigerant, waste heat recovery can be performed even when the temperature of the heat generating component (81) is low.
[0025]
Next, according to a seventh aspect of the present invention, in the sixth aspect, an accumulator (25) for separating the gas-liquid refrigerant is provided on the inlet side of the suction port (22b) of the compressor (22), and the accumulator (25 ), The liquid refrigerant in which the oil is dissolved is mixed with the gas refrigerant and sucked into the suction port (22b), and the first heat exchange means (74, 320) is arranged on the inlet side of the accumulator (25). It is characterized by that.
[0026]
According to this, the liquid refrigerant in which the oil is dissolved by the accumulator (25) can be reliably mixed into the low-pressure gas refrigerant and sent to the suction port (22b) of the compressor (22). As a result, the flow rate (flow velocity) of the refrigerant flowing through the outdoor heat exchanger (24) is reduced due to the decrease in the compressor rotation speed, and the oil in the refrigerant is likely to accumulate in the outdoor heat exchanger (24) even at a low heating load. The oil return property to the compressor (22) can be secured satisfactorily, and the durability of the compressor (22) can be improved. In addition, by arranging the first heat exchange means (74, 320) on the inlet side of the accumulator (25), a heat generating component can be added to the gas-liquid two-phase refrigerant on the accumulator inlet side (refrigerant lower in temperature than the gas refrigerant). The waste heat of (81) can be absorbed, and the waste heat can be recovered satisfactorily even when the heat generating component (81) is at a low temperature.
[0030]
In addition, the code | symbol in the bracket | parenthesis of each said means shows a corresponding relationship with the specific means as described in embodiment mentioned later.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
FIG. 1 is a first embodiment in which the present invention is applied to an air conditioner for an electric vehicle. An air conditioning unit 1 is installed in a vehicle interior of an electric vehicle, and an air conditioning duct 2 guides conditioned air into the vehicle interior. It constitutes an air conditioning passage. Suction ports 3, 4, and 5 for sucking inside and outside air are provided on one end side of the air conditioning duct 2. The inside air inlet 4 and the outside air inlet 5 are opened and closed by an inside / outside air switching door 6.
[0032]
A blower 7 for blowing air is installed in the air conditioning duct 2 adjacent to the suction ports 3 to 5, and this blower 7 is constituted by a motor (not shown) and fans 7a and 7b driven by this motor. Is done.
[0033]
On the other hand, on the other end of the air conditioning duct 2, a plurality of air outlets leading to the passenger compartment, that is, a foot air outlet 8 for blowing out the air conditioned air toward the foot of the passenger in the passenger compartment, and the conditioned air toward the upper body of the passenger in the passenger compartment. A defroster outlet 10 for blowing out conditioned air is formed on the face outlet 9 and the inner surface of the vehicle windshield.
[0034]
In addition, a cooling evaporator 11 is provided in the air conditioning duct 2 on the air downstream side of the blower 7. The cooling evaporator 11 is an indoor heat exchanger that constitutes a part of the refrigeration cycle 21, and in the cooling mode and the dehumidifying mode, which will be described later, the air in the air conditioning duct 2 is removed by the endothermic action of the refrigerant flowing inside. Functions as a dehumidifier / cooler. Moreover, it functions as a heater which heats the air in the air-conditioning duct 2 by the heat radiation action of the refrigerant flowing inside during the defrosting mode described later.
[0035]
Further, a heating condenser 12 is provided in the air conditioning duct 2 on the air downstream side of the cooling evaporator 11. The heating condenser 12 is an indoor heat exchanger that constitutes a part of the refrigeration cycle 21, and in the heating mode and dehumidification mode, which will be described later, the heat in the air conditioning duct 2 is radiated by the heat radiation action of the refrigerant flowing inside. Functions as a heater for heating.
[0036]
In addition, the air flow path in the air conditioning duct 2 is partitioned by a partition wall 13 into a first air flow path 14 on the foot outlet 8 side and a second air flow path 15 on the face outlet 9 and defroster outlet 10 side. It has been. This division of the air flow paths 14 and 15 is for carrying out the next two-layer mode of the inside and outside air during heating in winter. That is, during heating in winter, the first air flow path 14 on the foot outlet 8 side draws high-temperature inside air from the inside air inlet 3 and blows the temperature to the feet, thereby simultaneously reducing the heating load and at the same time defroster outlet 10 In order to implement the inside / outside air two-layer mode in which outside air with low humidity is sucked into the second air passage 15 on the side from the outside air inlet 5 and the front window is reliably prevented from being fogged, the air passages 14, 15 Is divided into two.
[0037]
The doors 16 and 17 are passage switching doors that switch between an air passage that passes through the condenser 12 and a bypass passage 12 a that bypasses the condenser 12. One door 17 also serves as a partition member for the air passages 14 and 15. Yes. Reference numeral 18 denotes a door disposed on the downstream side of the air flow paths 14 and 15, which switches between the partitioning action of the air flow paths 14 and 15 and the communication state of the air flow paths 14 and 15. Each of the outlets 8, 9, and 10 is opened and closed by an outlet switching door (not shown).
[0038]
By the way, the refrigeration cycle 21 is configured as a heat pump refrigeration cycle that performs cooling, heating, and dehumidification with a cooling evaporator 11 and a heating condenser 12, in addition to the evaporator 11 and the condenser 12. The following equipment is provided.
[0039]
That is, the refrigerant compressor 22, the refrigerant-refrigerant heat exchanger 23 that heat-exchanges gas-liquid two-phase intermediate pressure refrigerant with the high-pressure refrigerant and gasifies it, the outdoor heat exchanger 24, and the cycle low-pressure refrigerant (compressor suction refrigerant). An accumulator (gas-liquid separator) 25 that separates gas-liquid and stores excess liquid refrigerant, and a first pressure reducing device 26 that branches (bypasses) part of the high-pressure refrigerant after passing through the condenser 12 to reduce the pressure to an intermediate pressure. , A second decompressor 27 that decompresses the high-pressure refrigerant at the outlet of the refrigerant-refrigerant heat exchanger 23 to a low pressure during heating, and a third decompressor 29 that decompresses the high-pressure refrigerant after condensation from the outdoor heat exchanger 24 to a low pressure during cooling. The refrigeration cycle 21 includes solenoid valves (refrigerant path switching means) 28a, 28b, 28c for switching the refrigerant flow in each of the cooling, heating, dehumidification, and defrost modes, and a water-refrigerant heat exchanger 74.
[0040]
The outdoor heat exchanger 24 is installed outside the passenger compartment of the electric vehicle and exchanges heat with the outside air blown by the electric outdoor fan 24a. The refrigerant compressor 22 is an electric compressor, and an AC motor (not shown) is integrally incorporated in a sealed case, and is driven by the motor to suck, compress, and discharge the refrigerant. An AC voltage is applied to the AC motor of the refrigerant compressor 22 by an inverter 30, and the motor rotation speed is continuously changed by adjusting the frequency of the AC voltage by the inverter 30. Accordingly, the inverter 30 serves as a means for adjusting the rotational speed of the compressor 22, and a DC voltage from the in-vehicle battery 31 is applied to the inverter 30. The inverter 30 is energized and controlled by the air conditioning controller 40.
[0041]
The refrigerant compressor 22 is provided with a discharge port 22a that discharges the compressed refrigerant, a suction port 22b that sucks in the refrigerant on the low-pressure side of the cycle, and a gas injection port 22c that injects the intermediate-pressure gas refrigerant. The gas injection port 22c communicates with the refrigerant-refrigerant heat exchanger 23 via a gas injection passage 22d.
[0042]
Each of the first pressure reducing device 26, the second pressure reducing device 27, and the third pressure reducing device 29 is an electric expansion valve whose valve opening is electrically adjusted, and this electric expansion valve is, for example, a step motor. An electric drive means is provided, and the displacement amount of the valve body is adjusted by the electric drive means, and the opening degree of the refrigerant throttle passage is adjusted by the valve body. The first to third decompression devices 26, 27, and 29 can also be configured by fixed throttle means (for example, capillary tubes, orifices, etc.).
[0043]
The accumulator 25 has a U-shaped refrigerant outlet pipe 25a. The liquid refrigerant is supplied to the compressor 22 by storing excess liquid refrigerant on the bottom side and sucking gas refrigerant from the upper end opening of the U-shaped refrigerant outlet pipe 25a. Prevent back. At the same time, liquid refrigerant in which oil has melted is sucked from a small-diameter oil return hole (not shown) provided at the bottom of the U-shaped refrigerant outlet pipe 25a of the accumulator 25 and mixed with the gas refrigerant. The oil return property to the machine 22 is ensured.
[0044]
In addition, the high-pressure refrigerant pipe (main flow path) 32 connecting the refrigerant-refrigerant heat exchanger 23 and the second decompressor 27 detects the temperature and pressure of the high-pressure refrigerant at the outlet of the refrigerant-refrigerant heat exchanger 23. The refrigerant temperature sensor 41a and the high-pressure sensor 41b are installed. The output signals of the sensors 41a and 41b are input to the air conditioning control device 40, and the subcooling (supercooling degree) of the high-pressure refrigerant at the outlet of the refrigerant-refrigerant heat exchanger 23 is controlled by controlling the opening degree of the second decompression device 27. Control.
[0045]
The injection passage 22d is provided with an intermediate pressure refrigerant temperature sensor 41f and an intermediate pressure sensor 41g for detecting the temperature and pressure of the intermediate pressure refrigerant decompressed by the first decompression device 26. The output signals of the sensors 41f and 41g are inputted to the air conditioning controller 40, and the superheat (superheat degree) of the intermediate pressure refrigerant at the outlet of the refrigerant-refrigerant heat exchanger is controlled by controlling the opening degree of the first pressure reducing device 26. Control.
[0046]
The air-conditioning control device 40 is composed of a microcomputer and its peripheral circuits. The air-conditioning control device 40 includes an outside air temperature sensor 41c and an evaporator immediately after the evaporator in addition to the sensors 41a, 41b, 41f and 41g. From a sensor group 41 such as an evaporator temperature sensor 41d for detecting the air temperature, a discharge temperature sensor 41e for detecting the discharge gas temperature of the compressor 22, a refrigerant temperature sensor 41h at the outlet of the outdoor heat exchanger 24, and a current sensor 41i of the inverter 30. A sensor signal is input.
[0047]
The air-conditioning control device 40 is also input with a signal corresponding to the setting status of each lever operated by a passenger (user) from the air-conditioning control panel 50 (see FIG. 2).
[0048]
FIG. 1 shows only the electrical connection between the inverter 30 and the air conditioning control device 40, and does not show the electrical connection between other devices and the air conditioning control device 40. 3. The operation of the pressure reducing devices 26, 27, 29, electromagnetic valves 28a, 28b, 28c, doors 6, 16, 17, 18, an outlet switching door (not shown), the blower 7, and the outdoor fan 24a is also controlled by the control device 40. . The solenoid valves 28a, 28b, and 28c are controlled to be opened and closed by the control device 40 as shown in FIG. 8 to be described later, and the refrigerant circulation path is switched corresponding to each operation mode of cooling, heating, dehumidification, and defrosting.
[0049]
On the other hand, the refrigerant-refrigerant heat exchanger 23 has a cylindrical shape with a double passage structure in which an internal passage 23a and an external passage 23b are formed concentrically as shown in FIG. The internal passage 23a is located at the center, and a main-stream refrigerant (high-pressure refrigerant) that flows toward the outdoor heat exchanger 24 flows.
[0050]
On the other hand, the external passage 23b is formed by a large number of small passages arranged in parallel in the circumferential direction on the outer peripheral side of the internal passage 23a. The external passage 23b has an intermediate pressure reduced by the first pressure reducing device 26. The refrigerant flows from the bypass passage 63.
[0051]
Here, the tubular body 23c forming the internal passage 23a and the external passage 23b is molded (for example, extrusion molding) with a metal having excellent thermal conductivity such as aluminum, and a heat insulating material is formed on the outer surface of the tubular body 23c. Since 23d is fixed, heat exchange can be performed satisfactorily only between the high-pressure refrigerant in the internal passage 23a and the intermediate-pressure refrigerant in the external passage 23b.
[0052]
The refrigerant-refrigerant heat exchanger 23 is used as a part of the high-pressure side pipe 32 because the high-pressure refrigerant flows only in the internal passage 23a by fully closing the first decompression device 26 when gas injection is not required. Is called.
[0053]
The water-refrigerant heat exchanger 74 also has a cylindrical shape with a double-passage structure in which an internal passage (hot water passage) 74a and an external passage (refrigerant passage) 74b are formed concentrically as in the refrigerant-refrigerant heat exchanger 23. Can be configured. The intermediate pressure refrigerant flows into the external passage 74 b from the external passage 23 b of the refrigerant-refrigerant heat exchanger 23 through the pipe 71.
[0054]
The outlet side of the external passage 74b is connected to the injection port 22c through the injection passage 22d, and is connected to the pipe 72 provided with the defrosting electromagnetic valve 28c from the branch point 73a. This pipe 72 is connected to a branch point 73 b downstream of the third decompression device 29.
[0055]
Here, the hot water circuit 80 that circulates hot water in the internal passage (hot water passage) 74a of the water-refrigerant heat exchanger 74 will be described. The hot water circuit 80 cools the heat generating component 81 mounted on the electric vehicle. The heat generating component 81 is, for example, a semiconductor switch element (power transistor) of an inverter for controlling the rotational speed of an AC motor (not shown) for driving an electric vehicle.
[0056]
In addition to the water-refrigerant heat exchanger 74 described above, the hot water circuit 80 includes an electric water pump 82 for circulating hot water, a three-way valve (water circuit switching means) 83 of a solenoid valve type, and hot water (cooling water). A heat radiator 84 that dissipates heat into the outside air is provided. By the switching action of the three-way valve 35, the hot water heated by the heat generating component 81 flows to the water-refrigerant heat exchanger 74 side as indicated by the solid line arrow A, or flows to the radiator 84 side as indicated by the broken line arrow B. It has become.
[0057]
Next, the air-conditioning control panel 50 shown in FIG. 3 is provided with the following operation members that are manually operated by a passenger. Reference numeral 51 denotes a temperature control lever for setting a target value of the temperature of the air blown into the vehicle interior. In this example, the temperature control lever 51 is configured to set a target value for adjusting the rotational speed of the electric compressor 22.
[0058]
Moreover, the opening / closing of the solenoid valves 28a, 28b, 28c and the passage switching doors 16, 17 are controlled with respect to the target value set by the operation position of the temperature control lever 51, and the operation mode of the refrigeration cycle is switched.
[0059]
For example, as shown in FIG. 4, the operation mode is switched by sequentially moving the lever 51 from the left to the right to set the cooling mode, the dehumidifying mode, and the heating mode. Further, as shown in FIGS. 5, 6 and 7, by moving the operation position of the temperature control lever 51, the target evaporator outlet temperature is set during cooling, and the target high pressure is set during dehumidification and heating. Yes.
[0060]
The operation position signal of the temperature control lever 51 is input to the control device 40, and the control device 40 compresses the compressor so that the actual evaporator blown air temperature or high pressure detected by the sensor group 41 matches the target value. The rotation speed of 22 is controlled and the blown air temperature is controlled.
[0061]
52 is a speed (air volume) switching lever of the blower 7, 53 is an air conditioner switch for intermittently operating the compressor 22, and 54 is an air conditioning blowing mode switching lever for opening and closing a switching door (not shown) of the outlets 8, 9, and 10. , 55 is an inside / outside air switching lever that opens and closes the inside / outside switching door 6.
[0062]
Next, the operation of the first embodiment in the above configuration will be described. When the air conditioner switch 53 is turned on, the signal is turned on to the control device 40 to start the compressor 22. In this state, when the temperature control lever 51 is in the position from PH2 to PH1 in FIG. 4, the control device 40 determines that the heating mode is selected and displays the devices such as the electromagnetic valves 28a, 28b, 28c, the passage switching doors 16, 17 and the like. Control to the state of 8 heating mode.
[0063]
Black arrows in FIG. 1 indicate the refrigerant flow in the heating mode, and FIG. 9 is a Mollier diagram showing the state of the refrigerant in the refrigeration cycle in the heating mode. The high-temperature and high-pressure superheated gas refrigerant discharged from the compressor 22 first flows into the condenser 12 set indoors, where it exchanges heat (radiates heat) with the air blown by the blower 7, and the gas refrigerant is condensed. To do. The warm air heated by the condensation of the gas refrigerant is mainly blown into the vehicle compartment from the foot outlet 8 to heat the vehicle compartment.
[0064]
A portion of the high-pressure refrigerant that has flowed out of the condenser 12 is branched from the branch point 61a to the bypass passage 63 side because the cooling electromagnetic valve 28b is closed. The branched high-pressure refrigerant flows into the first decompression device 26 and is decompressed to the intermediate pressure PM. The two-phase refrigerant decompressed to the intermediate pressure PM passes through the external passage 23b of the refrigerant-refrigerant heat exchanger 23 and exchanges heat with the high-pressure refrigerant at the outlet of the indoor condenser 12 that passes through the internal passage 23a. To increase.
[0065]
In the heating mode, the hot water heated by the heat generating component 81 of the hot water circuit 80 flows to the water-refrigerant heat exchanger 74 side as indicated by the solid arrow A by the three-way valve 83, and therefore the external passage 23b of the refrigerant-refrigerant heat exchanger 23. The intermediate-pressure refrigerant flowing out of the gas is gasified with increased dryness by heat exchange (heat absorption) with warm water in the water-refrigerant heat exchanger 74.
[0066]
Since the solenoid valve 28c is in the closed state in the heating mode, the intermediate-pressure gas refrigerant flows into the injection port 22c through the injection passage 22d.
[0067]
On the other hand, the high-pressure refrigerant passing through the internal passage 23a of the refrigerant-refrigerant heat exchanger 23 exchanges heat (dissipates heat) with the refrigerant passing through the external passage 23b, and is supercooled. The supercooled high-pressure refrigerant flows into the second decompression device 27, is decompressed to the low pressure PL by the second decompression device 27, and flows into the outdoor heat exchanger 24. When the low-pressure refrigerant passes through the outdoor heat exchanger 24, the low-pressure refrigerant absorbs heat from the blown air (outside air) of the outdoor fan 24a and evaporates.
[0068]
The gas refrigerant evaporated in the outdoor heat exchanger 24 flows into the accumulator 25 through the heating solenoid valve 28a in the open state, and the liquid refrigerant generated by the fluctuation of the heating load is stored in the accumulator 25. In the accumulator 25, the gas refrigerant is sucked from the upper end opening of the U-shaped refrigerant outlet pipe 25a, and oil is dissolved from an oil return hole (not shown) provided in the bottom of the U-shaped refrigerant outlet pipe 25a. The refrigerant is sucked and mixed with the gas refrigerant, and the gas refrigerant is sucked into the suction port 22 b of the compressor 22. Accordingly, the oil can be reliably returned to the compressor 22 even under a condition in which the refrigerant flow rate is small as in the case of an intermediate heating and low load.
[0069]
The opening of the first pressure reducing device (electric expansion valve) 26 is controlled by the control device 40 based on the detection signals of the temperature sensor 41f and the pressure sensor 41g of the intermediate pressure refrigerant, and flows into the injection port 22c of the compressor 22. The flow rate of the refrigerant is controlled so that the superheat SH of the gas injection refrigerant to be performed becomes a predetermined amount. That is, if the superheat SH of the gas injection refrigerant increases, the opening degree of the first decompression device (electric expansion valve) 26 is increased, and conversely, if the superheat SH decreases, the first decompression device (electric expansion). The opening of the valve 26 is decreased. Excessive liquid return to the compressor 22 can be prevented by such superheat control of the gas injection refrigerant.
[0070]
In addition, the opening degree of the second decompression device 27 is controlled by the control device 40, and the refrigerant-refrigerant heat exchange is performed so that the subcool SC of the high-pressure refrigerant exiting the internal passage 23a of the refrigerant-refrigerant heat exchanger 23 becomes a predetermined amount. The amount of exchange heat in the vessel 23 is controlled. That is, when the subcool SC of the high-pressure refrigerant increases, the opening degree of the second decompression device 27 is increased to lower the high pressure and reduce the subcool SC. Conversely, if the subcool SC of the high-pressure refrigerant is reduced, the opening of the second decompression device 27 is decreased to increase the high pressure, and the subcool SC is increased.
[0071]
In FIG. 9, Gi is a refrigerant flow rate that is gas-injected from the injection passage 22d to the injection port 22c, Ge is a refrigerant flow rate that is drawn into the compressor 22 through the outdoor heat exchanger (evaporator during heating), Δi₁Is the enthalpy difference of the intermediate pressure refrigerant on the gas injection side that absorbs heat in the refrigerant-refrigerant heat exchanger 23 and the water-refrigerant heat exchanger 74, and Δi₂Is the enthalpy difference of the high-pressure refrigerant that dissipates heat in the refrigerant-refrigerant heat exchanger 23 and travels toward the second decompression device 27.
[0072]
Further, since the passage switching doors 16 and 17 open the air passage on the condenser 12 side and fully close the bypass passage 12a, the high-temperature and high-pressure refrigerant discharged from the compressor 22 and the air blown by the blower 7 are condensed into the condenser. 12 to heat exchange.
[0073]
FIG. 10 shows the pressure (intermediate pressure) of the intermediate-pressure refrigerant decompressed by the first decompression device 26 on the horizontal axis, and the vertical axis represents the superheat SH and heating capacity Qc of the injection refrigerant. The superheat SH is predetermined. At the value T1, when there is no waste heat recovery in the water-refrigerant heat exchanger 74, the intermediate pressure = Pm, and the heating capacity Qc at that time is Q1.
[0074]
On the other hand, when the waste heat is recovered from the hot water by the water-refrigerant heat exchanger 74 as in the present embodiment, even if the superheat SH is controlled to the same value T1, the waste heat is recovered from the hot water. Since the gasification of the pressurized refrigerant is promoted, the intermediate pressure can be increased from Pm to Pm1 as shown in FIG. As the intermediate pressure increases, the gas injection refrigerant flow rate increases from Gi to Gi1, and the heating capacity Qc can be improved from Q1 to Q2 in FIG. FIG. 11 is a Mollier diagram showing the change of the cycle refrigerant state depending on the presence or absence of waste heat recovery.
[0075]
Next, the defrosting mode in the heating mode will be described. In the heating mode, the condensed water generated in the outdoor heat exchanger 24 acting as an evaporator is frozen, and a frosted state occurs in the outdoor heat exchanger 24. When the frosting state of the outdoor heat exchanger 24 is determined by the control device 40, the devices such as the electromagnetic valves 28a, 28b, 28c and the passage switching doors 16, 17 are switched to the state in the defrosting mode of FIG. .
[0076]
Although the frosting state of the outdoor heat exchanger 24 can be determined by various methods, in this example, the frosting of the outdoor heat exchanger 24 reduces the outlet refrigerant temperature Tho of the outdoor heat exchanger 24 and When the difference between the temperature Tam and the outlet refrigerant temperature Tho (Tam−Tho) becomes larger than a predetermined value (for example, 20 ° C.), it is assumed that the outdoor heat exchanger 24 is in a frosted state and the cycle is changed to the defrosting mode of FIG. Switch to state.
[0077]
The arrows in FIG. 12 indicate the flow direction of the refrigerant in the defrosting mode, and FIG. 13 is a Mollier diagram showing the state change of the refrigerant in the defrosting mode.
[0078]
In the defrosting mode, the air passage of the condenser 12 is fully closed by the passage switching doors 16 and 17, so that all the air blown from the blower 7 passes through the bypass passage 12 a of the condenser 12. Therefore, the discharged gas refrigerant from the compressor 22 does not exchange heat in the condenser 12, passes through the condenser 12 as it is immediately after discharge, and is branched into two flows at the branch point 61a.
[0079]
That is, one refrigerant flow radiates heat through the internal passage 23 a of the refrigerant-refrigerant heat exchanger 23, and then is decompressed by the second decompression device 27 and flows into the outdoor heat exchanger 24. Here, the decompressed gas refrigerant (hot gas) dissipates heat in the outdoor heat exchanger 24 to melt the frost in the outdoor heat exchanger 24. The refrigerant that has passed through the outdoor heat exchanger 24 flows into the accumulator 25 through the heating electromagnetic valve 28a in the open state.
[0080]
The other refrigerant flow from the branch point 61a flows into the first decompression device 26 and is decompressed. The decompressed gas refrigerant passes through the external passage 23b of the refrigerant-refrigerant heat exchanger 23, exchanges heat with the high-pressure gas refrigerant passing through the internal passage 23a, absorbs heat, and then passes through the external passage (refrigerant) of the water-refrigerant heat exchanger 74. The heat is absorbed again from the hot water in the passage 74b.
[0081]
Thereafter, the gas refrigerant passes through the defrosting electromagnetic valve 28 c and flows into the indoor evaporator 11, and dissipates heat into the blown air of the blower 7. The refrigerant that has passed through the indoor evaporator 11 flows into the accumulator 25, merges with the refrigerant that has passed through the outdoor heat exchanger 24, and is sucked into the compressor 22.
[0082]
The blown air (warm air) heated by the indoor evaporator 11 passes through the bypass passage 12a of the condenser 12 and blows out mainly from the foot outlet 8 into the vehicle interior to heat the vehicle interior. Therefore, since heating of the passenger compartment can be continued even during defrosting, a decrease in the passenger compartment temperature during defrosting can be suppressed. In the defrosting mode, the first and second decompression devices 26 and 27 are held at a predetermined control opening set in advance.
[0083]
As the defrosting mode proceeds, the outlet refrigerant temperature Tho of the outdoor heat exchanger 24 rises, and the difference between the outside air temperature Tam and this outlet refrigerant temperature Tho (Tam−Tho) is a predetermined value (for example, 20 ° C.) or less. And when the state continues for a predetermined time (for example, 10 seconds) or longer, it is determined that the defrosting of the outdoor heat exchanger 24 is completed, and the mode is automatically returned to the heating mode.
[0084]
Next, when the temperature control lever 51 is in the position of PC1 to PC2 in FIG. 3, the control device 40 determines that the cooling mode is selected, and the devices such as the electromagnetic valves 28a, 28b, 28c, the passage switching doors 16, 17 and the like are shown in FIG. Control to the state of the cooling mode. The white arrow in FIG. 1 indicates the refrigerant flow in the cooling mode.
[0085]
In the cooling mode, the passage switching doors 16 and 17 fully close the air passage on the condenser 12 side, so that all the air blown from the blower 7 flows through the bypass passage 12a. Therefore, the high-temperature and high-pressure superheated gas refrigerant discharged from the compressor 22 does not exchange heat (dissipate heat) with the blown air of the blower 7 in the condenser 12, and therefore remains in a superheated state immediately after being discharged from the compressor 22. Through the condenser 12.
[0086]
At this time, since the first and second pressure reducing devices (electrical expansion valves) 26 and 27 are controlled to be in a fully closed state, the entire amount of the gas refrigerant discharged from the compressor 22 is in an open state. It flows into the outdoor heat exchanger 24 through the valve 28 b and the bypass passage 62.
[0087]
In the outdoor heat exchanger 24, the high-pressure gas refrigerant is condensed by exchanging heat (radiating heat) with the blown air (outside air) of the outdoor fan 24a. Then, the refrigerant condensed in the outdoor heat exchanger 24 passes through the third pressure reducing device 29 by the valve closing of the electromagnetic valves 28 a and 28 c, is reduced to the low pressure PL, and then flows into the evaporator 11. Here, the third decompression device 29 has a valve opening degree so that the subcooling of the refrigerant at the outlet of the outdoor heat exchanger 24 becomes a predetermined value based on detection signals of the high pressure sensor 41b and the outlet refrigerant temperature sensor 41h of the outdoor heat exchanger 24. Be controlled.
[0088]
In the evaporator 11, the refrigerant absorbs heat from the air blown from the blower 7 and evaporates, and the cold air cooled by the evaporator 11 does not pass through the indoor condenser 12 on the downstream side as described above, and its bypass passage 12a. The air is passed through the vehicle as it is, and is blown out mainly from the face air outlet 9 into the vehicle interior to cool the vehicle interior.
[0089]
On the other hand, the gas refrigerant evaporated in the evaporator 11 flows into the accumulator 25, and the gas refrigerant is sucked into the suction port 22 b of the compressor 22 from the accumulator 25.
[0090]
Next, when the temperature control lever 51 is in the position of PD1 to PD2 in FIG. 3, the control device 40 determines the dehumidifying mode, and the devices such as the electromagnetic valves 28a, 28b and 28c, the passage switching doors 16 and 17 are shown in FIG. Control to the dehumidifying mode. The hatched arrows in FIG. 1 indicate the refrigerant flow path in the dehumidifying mode.
[0091]
In the dehumidifying mode, since the air passage of the condenser 12 is opened by the passage switching doors 16 and 17, the high-temperature and high-pressure superheated gas refrigerant discharged from the compressor 22 flows into the condenser 12, where the blower 7 blows air. Heat exchange (heat radiation) with air causes the gas refrigerant to condense.
[0092]
At this time, since the first pressure reducing device 26 and the cooling electromagnetic valve 28 b are fully closed, the entire amount of the high-pressure refrigerant condensed by the condenser 12 passes through the internal passage 23 a of the refrigerant-refrigerant heat exchanger 23. At this time, the refrigerant passing through the internal passage 23a is not cooled, passes through the refrigerant-refrigerant heat exchanger 23 and flows into the second decompression device 27 as it exits the indoor condenser 12, 2 The pressure is reduced to an intermediate pressure by the pressure reducing device 27 and flows into the outdoor heat exchanger 24.
[0093]
Here, the intermediate pressure produced by the second pressure reducing device 27 is the first dehumidifying mode D that requires a high blowing temperature in the dehumidifying mode.₁Then, by setting it lower than the saturation pressure of the refrigerant with respect to the outside air temperature, the outdoor heat exchanger 24 can act as an evaporator and can be set on the heat absorption side. That is, the intermediate pressure is set low by decreasing the opening degree of the second pressure reducing device 27 and increasing the pressure reduction amount.
[0094]
Then, the intermediate pressure refrigerant that has flowed out of the outdoor heat exchanger 24 flows into the third decompression device 29 by the closing of the heating electromagnetic valve 28a, and is decompressed to the low pressure PL. The decompressed low-pressure refrigerant flows into the evaporator 11, absorbs heat from the blown air of the blower 7 and evaporates, and then flows into the accumulator 25. The gas refrigerant is sucked from the accumulator 25 into the suction port 22 b of the compressor 22.
[0095]
In the dehumidifying mode, the refrigerant flows through both the evaporator 11 and the condenser 12 set in the indoor air conditioning unit 1, and the air blown from the blower 7 is first cooled and dehumidified by the evaporator 11, and then the condenser 12. It is reheated and becomes warm air. This warm air is mainly blown out from the differential outlet 10 into the vehicle interior to prevent fogging of the window glass and to dehumidify and heat the vehicle interior.
[0096]
By the way, in the dehumidification mode, the 1st dehumidification mode D which requires high blowing temperature₁Then, since the sum of the power of the compressor 22, the heat absorption amount of the outdoor heat exchanger 24, and the heat absorption amount in the indoor evaporator 11 can be radiated from the indoor condenser 12, a desired high blowing temperature can be created.
[0097]
On the other hand, in the dehumidification mode, the second dehumidification mode D which requires a low blowing temperature₂Then, by setting the intermediate pressure produced by the second decompression device 27 higher than the saturation pressure of the refrigerant with respect to the outside air temperature, the outdoor heat exchanger 24 can act as a condenser and can be set on the heat radiation side. That is, the intermediate pressure is set high by increasing the valve opening degree of the second pressure reducing device 27 and reducing the pressure reduction amount.
[0098]
As a result, the outdoor heat exchanger 24 becomes a condenser and acts as a heat radiating side, so that the total power absorbed by the power L of the compressor 22 and the indoor evaporator 11, the heat radiating amount Qeh in the outdoor heat exchanger 24, and the room The sum of the heat radiation amount Qc in the condenser 11 becomes equal. Therefore, the heat radiation amount in the indoor condenser 11 is the first dehumidifying mode D.₁Therefore, the target low blowing temperature can be produced.
[0099]
According to the first embodiment, the cycle refrigerant circulation path can be simplified for the following reasons. That is, even in the defrosting mode and the cooling mode, the passage switching doors 16 and 17 block the air flow to the condenser 12 so that air passes through the bypass passage 12a. It becomes a part of the refrigerant passage through which. For this reason, the refrigerant continues to flow through the condenser 12 through all modes of heating, cooling, dehumidification, and defrosting. Therefore, the refrigerant discharged from the compressor 22 is always directed to the outdoor heat exchanger 24 and the like through the condenser 12. Can flow in the direction. As a result, the four-way valve for reversing the refrigerant flow direction can be eliminated, or the number of valve devices such as a check valve and a solenoid valve for switching the refrigerant flow path can be reduced, and the refrigerant piping configuration can be simplified. .
[0100]
(Second Embodiment)
FIG. 14 shows the second embodiment. In the first embodiment, a three-way valve 83 is provided in the hot water circuit 80, and the hot water heated by the heat generating component 81 in the heating and defrosting mode is converted into a water-refrigerant as indicated by a solid arrow A. In the cooling and dehumidifying modes, the hot water heated by the heat generating component 81 is allowed to flow toward the radiator 84 as indicated by the broken-line arrow B, but in the second embodiment, the three-way valve 83 is allowed to flow. The heat radiator 84 is abolished so that hot water always flows through the water-refrigerant heat exchanger 74.
[0101]
According to the second embodiment, it is necessary to always cool the heat generating component 81 with the water-refrigerant heat exchanger 74 when the radiator 84 is abolished. Therefore, the refrigerant is always circulated to the injection passage 22d side, and the temperature discharged from the compressor rises due to the rise in the temperature of the injection refrigerant in the cooling mode, but the cost can be reduced by reducing the number of parts of the hot water circuit 80. .
[0102]
(Third embodiment)
FIG. 15 shows a third embodiment. In the first embodiment, a water-refrigerant heat exchanger 74 is provided on the side of the injection passage 22d through which the intermediate-pressure refrigerant flows, and waste heat recovery of the heat generating component 81 is performed by the injection refrigerant. However, in the third embodiment, waste heat recovery of the heat generating component 81 is performed by the low-pressure side refrigerant.
[0103]
That is, as shown in FIG. 15, a water-refrigerant heat exchanger 74 is provided between the junction 73 c between the outlet side of the evaporator 11 and the outlet side of the heating solenoid valve 28 a and the inlet portion of the accumulator 25. Yes.
[0104]
According to the third embodiment, the refrigerant from the outlet of the evaporator 11 flows through the external passage (refrigerant passage) 74b of the water-refrigerant heat exchanger 74 at the time of cooling. In the mode, the effect of increasing the amount of the injection refrigerant by waste heat recovery cannot be exhibited. Instead, in the third embodiment, even when the hot water temperature of the hot water circuit 80 is low, the waste heat recovery from the hot water is performed for heating capacity. Can be improved.
[0105]
16 is a Mollier diagram (corresponding to FIG. 13) in the defrosting mode according to the third embodiment. In the external passage (refrigerant passage) 74b of the water-refrigerant heat exchanger 74, the gas-liquid on the inlet side of the accumulator 25 is shown. Two-phase low-pressure refrigerant flows. Since the temperature of the low-pressure refrigerant in the gas-liquid two-phase region is sufficiently lower than the refrigerant in the superheated gas region, the temperature difference between the hot water and the refrigerant is ensured even if the hot water temperature in the hot water circuit 80 is somewhat lower, Heating capacity can be improved by recovering waste heat from hot water. This effect can be exhibited not only in the defrost mode but also in the heating mode.
[0106]
13 and 16, the refrigerant pressure in the evaporator 11 is shown in a state lower than the refrigerant pressure in the outdoor heat exchanger 24 for reasons of drawing drawing, but actually the refrigerant pressure in both 11 and 24 is shown. Of course, they are equivalent.
[0107]
(Fourth embodiment)
FIG. 17 shows a fourth embodiment. In the first to third embodiments, a water-refrigerant heat exchanger (first heat exchange means) 74 and a refrigerant-refrigerant heat exchanger (second heat exchange means) 23 are respectively provided. Although comprised independently, in 4th Embodiment, as shown in FIGS. 17-19, both the heat exchangers 23 and 74 are comprised as one integrated heat exchanger 230. FIG.
[0108]
A specific example of the integrated heat exchanger 230 will be described with reference to FIGS. 18 and 19. The high-pressure refrigerant passage portion 230a corresponding to the internal passage 23a through which the high-pressure refrigerant flows in the refrigerant-refrigerant heat exchanger 23, and the refrigerant-refrigerant heat exchanger. The intermediate pressure refrigerant passage portion 230b corresponding to the external passage 23b through which the intermediate pressure refrigerant flows in 23 and the hot water passage portion 230c corresponding to the internal passage 74a through which the hot water flows in the water-refrigerant heat exchanger 74 are integrated.
[0109]
At the time of this integration, each of the three passage portions 230a to 230c is constituted by a flat multi-hole tube extruded by a metal such as aluminum, and the intermediate pressure refrigerant passage portion 230b is set at the center and both sides thereof are formed. In addition, the high-pressure refrigerant passage portion 230a and the hot water passage portion 230c are closely joined and integrated.
[0110]
(Other embodiments)
In the first to fourth embodiments described above, the branch point 61a on the outlet side of the condenser 12 (upstream side of the refrigerant-refrigerant heat exchanger 23) and the inlet side of the outdoor heat exchanger 24 (second decompression device). 27 is provided with a bypass passage 62 that directly couples to a junction 61b on the downstream side of 27, and an electromagnetic valve (electrical opening / closing means) 28b is inserted into the bypass passage 60. 28b may be directly connected in parallel between the inlet and the outlet of the second pressure reducing device 27.
[0111]
In each of the embodiments described above, two plate-shaped passage switching doors 16 and 17 that are operated in conjunction are used as door means for switching the air flow to the condenser 12 and the air flow to the bypass passage 12a. Of course, a single plate-like door or a film-like door may be used as the door means.
[Brief description of the drawings]
FIG. 1 is a refrigeration cycle diagram showing a first embodiment of the present invention.
FIG. 2 is a cross-sectional view showing a specific example of a refrigerant-refrigerant heat exchanger used in the first embodiment.
FIG. 3 is a front view of an air conditioning control panel used in the first embodiment.
4 is a characteristic diagram of an operation region and an operation mode of a temperature control lever in the air conditioning control panel of FIG. 3;
FIG. 5 is a characteristic diagram of a cooling region of the temperature control lever.
FIG. 6 is a characteristic diagram of a dehumidifying region of the temperature control lever.
FIG. 7 is a characteristic diagram of a heating region of the temperature control lever.
FIG. 8 is a chart for explaining operations of valves and doors used in the first embodiment.
FIG. 9 is a Mollier diagram illustrating the operation of the refrigeration cycle in the heating mode in the first embodiment.
FIG. 10 is an explanatory diagram of heating capacity depending on whether or not waste heat is recovered in the first embodiment.
FIG. 11 is a Mollier diagram illustrating a difference in operation of the refrigeration cycle depending on whether or not waste heat is recovered in the first embodiment.
FIG. 12 is a refrigeration cycle diagram for explaining the operation at the time of defrosting in the first embodiment.
FIG. 13 is a Mollier diagram illustrating an operation during defrosting in the first embodiment.
FIG. 14 is a refrigeration cycle diagram showing a second embodiment of the present invention.
FIG. 15 is a refrigeration cycle diagram showing a third embodiment of the present invention.
FIG. 16 is a Mollier diagram illustrating the operation during defrosting in the third embodiment.
FIG. 17 is a refrigeration cycle diagram showing a fourth embodiment.
FIG. 18 is a schematic perspective view illustrating an integrated heat exchanger according to a fourth embodiment.
19 is a cross-sectional view of each passage joint in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Evaporator, 12 ... Condenser, 16, 17 ... Passage switching door, 22 ... Compressor,
22c ... Gas injection port, 22d ... Gas injection passage, 23 ... Refrigerant-refrigerant heat exchanger, 24 ... Outdoor heat exchanger, 25 ... Accumulator,
26 ... 1st decompression device, 27 ... 2nd decompression device, 29 ... 3rd decompression device,
74 ... Water-refrigerant heat exchanger, 81 ... Heat-generating component.

Claims

An air conditioning passage (2) through which air flows into the room;
A compressor (22) for compressing and discharging the refrigerant;
A condenser (12) that is installed in the air conditioning passage (2) and that heats the air with a refrigerant gas discharged from the compressor (22);
A bypass passage (12a) that is formed in the air conditioning passage (2) and flows the air bypassing the condenser (12);
Door means (16, 17) installed in the air conditioning passage (2), for switching between an air flow to the condenser (12) and an air flow to the bypass passage (12a);
An outdoor heat exchanger (24) installed outdoors;
A heating decompressor (27) installed on the refrigerant inlet side of the outdoor heat exchanger (24);
An evaporator (11) installed upstream of the condenser (12) in the air conditioning passage (2);
A cooling decompression device (29) installed on the refrigerant inlet side of the evaporator (11);
A refrigerant bypass passage (63) through which the refrigerant flows by bypassing the heating decompression device (27);
A bypass-side pressure reducing device (26) provided in the refrigerant bypass passage (63) ,
The discharge side of the compressor (22) is always connected to the condenser (12), and the discharge gas refrigerant from the compressor (22) always passes through the condenser (12) and the outdoor heat exchanger. (24) to flow in one direction to the side,
In the heating mode, the discharge gas refrigerant of the compressor (22) is changed by switching the door means (16, 17) to a position where the blown air in the air conditioning passage (2) passes through the condenser (12). The refrigerant is condensed by flowing into the condenser (12) and dissipating heat to the blown air in the air conditioning passage (2), and the high-pressure refrigerant after passing through the condenser (12) is decompressed by the heating decompression device (27). The low-pressure refrigerant after passing through the heating decompression device (27) flows into the outdoor heat exchanger (24) and evaporates, and the low-pressure refrigerant after passing through the outdoor heat exchanger (24) is adapted to be sucked into the compressor (22), wherein in the heating mode is blown a hot air heated by the condenser (12) into the room,
In the cooling mode, by switching the door means (16, 17) to a position where the blown air in the air conditioning passage (2) passes through the bypass passage (12a), the discharge gas refrigerant of the compressor (22) is changed. The outdoor heat exchanger (24) passes through the condenser (12) without exchanging heat with the blown air in the air conditioning passage (2), and the discharged gas refrigerant after passing through the condenser (12) remains in a high pressure state. And the discharge gas refrigerant condenses in the outdoor heat exchanger (24), and the high-pressure refrigerant after passing through the outdoor heat exchanger (24) is decompressed by the cooling decompression device (29) to be in a low pressure state. Then, the low-pressure refrigerant after passing through the cooling decompression device (29) flows into the evaporator (11) and absorbs heat from the blown air in the air-conditioning passage (2) to evaporate, and the evaporator (11) The low-pressure refrigerant after passing is compressed (22) is adapted to be sucked into the cool air cooled by the evaporator (11) in the cooling mode is blown into the room through the bypass passage (12a),
In the dehumidifying mode, the discharge gas refrigerant of the compressor (22) is changed by switching the door means (16, 17) to a position where the blown air in the air conditioning passage (2) passes through the condenser (12). The refrigerant is condensed by flowing into the condenser (12) and dissipating heat to the blown air in the air conditioning passage (2), and the high-pressure refrigerant after passing through the condenser (12) is decompressed by the heating decompression device (27). The intermediate-pressure refrigerant after passing through the heating pressure reducing device (27) flows into the outdoor heat exchanger (24) and exchanges heat with outdoor air, and passes through the outdoor heat exchanger (24). The subsequent intermediate pressure refrigerant is decompressed by the cooling decompression device (29) to be in a low pressure state, and the low pressure refrigerant after passing through the cooling decompression device (29) flows into the evaporator (11) and enters the air conditioning passage ( 2) To absorb heat from the blown air inside Evaporated, the evaporator (11) low-pressure refrigerant after passing through are adapted to be sucked into the compressor (22), the condensed cooling dehumidified cold air by the evaporator in the dehumidifying mode (11) It was blown into the room and re-heated in a vessel (12),
When setting the defrost mode for defrosting the outdoor heat exchanger (24) in the heating mode, the door is located at a position where the blown air in the air conditioning passage (2) passes through the bypass passage (12a). By switching the means (16, 17), the discharge gas refrigerant of the compressor (22) passes through the condenser (12) without exchanging heat with the blown air in the air conditioning passage (2), and the condenser (12) The discharged gas refrigerant after passing is branched into a flow toward the heating decompression device (27) and a flow toward the refrigerant bypass passage (63) ,
One of the branch gas refrigerants is decompressed by the heating decompression device (27) to become a low pressure state, and the low-pressure gas refrigerant after passing through the heating decompression device (27) flows into the outdoor heat exchanger (24). The outdoor heat exchanger (24) is defrosted, and the low-pressure refrigerant after passing through the outdoor heat exchanger (24) is sucked into the compressor (22).
Further, the other of the branch gas refrigerant flows into the refrigerant bypass passage (63) and is decompressed by the bypass side decompression device (26) to become a low pressure state, and is in a low pressure state after passing through the bypass side decompression device (26). After the gas refrigerant flows into the evaporator (11), the blower air in the air conditioning passage (2) is heated by the low-pressure gas refrigerant in the evaporator (11), and after passing through the evaporator (11) The low-pressure refrigerant is also drawn into the compressor (22), and in the defrost mode, the warm air heated by the evaporator (11) passes through the bypass passage (12a) and passes through the room. A refrigeration cycle apparatus characterized by being blown out .

Having first heat exchange means (74, 320) for recovering waste heat of the heat generating component (81);
During the defrosting mode, the low-pressure gas refrigerant decompressed by the bypass side decompression device (26) absorbs the waste heat of the heat generating component (81) by the first heat exchange means (74, 320) , the refrigeration cycle apparatus according to claim 1 in which the gas refrigerant of the low pressure state after absorbs waste heat is equal to or flowing into the evaporator (11).

The compressor (22) includes a discharge port (22a) for discharging a compressed refrigerant, a suction port (22b) for sucking a refrigerant on the low pressure side of the refrigeration cycle, and a gas injection port (6) for introducing a gas refrigerant on the intermediate pressure side of the refrigeration cycle. 22c)
Even in the heating mode, the high-pressure refrigerant condensed in the condenser (12) branches into a flow toward the heating decompression device (27) and a flow toward the refrigerant bypass passage (63),
One of the branch refrigerants is decompressed by the heating decompression device (27) to become a low pressure state and flows into the outdoor heat exchanger (24),
The other of the branch refrigerants is depressurized to an intermediate pressure by the bypass side depressurization device (26 ), and the waste heat of the heat generating component (81) is absorbed into the intermediate pressure refrigerant by the first heat exchange means (74, 320). The intermediate pressure refrigerant is gasified, and the intermediate pressure gas refrigerant flows into the gas injection port (22c) .
In the heating mode, the low-pressure refrigerant after passing through the outdoor heat exchanger (24) is sucked into the suction port (22b), and in the cooling mode, the low-pressure refrigerant after passing through the evaporator (11) is sucked into the suction port (22). 22b), and in the defrosting mode, the low-pressure refrigerant after passing through the outdoor heat exchanger (24) and the low-pressure refrigerant after passing through the evaporator (11) are sucked into the suction port (22b). The refrigeration cycle apparatus according to claim 2, characterized in that:

In the heating mode, heat exchange is performed between the high-pressure refrigerant that is the one of the branched refrigerants toward the heating decompression device (27) and the intermediate-pressure refrigerant decompressed by the bypass-side decompression device (26). The refrigeration cycle apparatus according to claim 3, further comprising second heat exchange means (23, 230).

The refrigeration cycle apparatus according to claim 4, wherein the first heat exchange means and the second heat exchange means are integrally configured as one heat exchanger (230).

Having first heat exchange means (74, 320) for recovering waste heat of the heat generating component (81);
Waste heat of the heat generating component (81) is discharged by the first heat exchange means (74, 320) into the low-pressure refrigerant that has passed through the outdoor heat exchanger (24) and is sucked into the compressor (22) in the heating mode. Endotherm,
Wherein the defrost mode, the sucked into the compressor (22) is sucked into the outdoor heat exchanger (24) low-pressure refrigerant after passing through, and the compressor (22), the evaporator (11) 2. The refrigeration cycle apparatus according to claim 1, wherein the waste heat of the heat generating component (81) is absorbed into the low-pressure refrigerant after passing by the first heat exchange means (74, 320).

An accumulator (25) for separating the gas-liquid refrigerant is provided on the inlet side of the suction port (22b),
From the accumulator (25), liquid refrigerant in which oil is dissolved is mixed with gas refrigerant and sucked into the suction port (22b).
The refrigeration cycle apparatus according to claim 6, wherein the first heat exchange means (74, 320) is disposed on an inlet side of the accumulator (25).