JP2004051077A

JP2004051077A - Air conditioner for vehicle

Info

Publication number: JP2004051077A
Application number: JP2002372092A
Authority: JP
Inventors: Taiichi Aikawa; 相川　泰一; Yasushi Yamanaka; 山中　康司; Makoto Kume; 粂　真; Takahisa Suzuki; 鈴木　隆久
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 2002-05-29
Filing date: 2002-12-24
Publication date: 2004-02-19
Anticipated expiration: 2022-12-24
Also published as: JP4013756B2

Abstract

<P>PROBLEM TO BE SOLVED: To minimize a mounting space in vehicle of a cold storage type air conditioner for a vehicle. <P>SOLUTION: A liquid refrigerant tank section 10a is integrally formed on the lower portion of a tank member 10. A cold storage heat exchanger 11 is placed in the upper internal portion of the tank member 10. A liquid refrigerant circulating pump 15 is placed underneath the cold storage heat exchanger 11 in the tank member 10. When a compressor is operated, a cold storage material 11a' of the cold storage heat exchanger 11 is cooled down by a low-pressure refrigerant which is depressurized by an expansion valve 7, and the low-pressure refrigerant is flowed into an evaporator through an outlet pipe 14. When the compressor is stopped after a vehicle engine stop, cooling refrigerant of the liquid refrigerant tank section 10a is introduced into the evaporator by the liquid refrigerant circulating pump 15, and is cooled down and condensed by cold/heat storage of the cold storage material 11a' by introducing a gaseous-phase refrigerant which is evaporated by the evaporator into the cold storage heat exchanger 11. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、停車時等に圧縮機の駆動源である車両エンジンを一時的に停止させる車両に適用される蓄冷式の車両用空調装置に関するものである。
【０００２】
【従来の技術】
近年、環境保護、車両エンジンの燃費向上等を目的にして、信号待ち等の停車時に車両エンジンを自動的に停止する車両（ハイブリッド車等のエコラン車）が実用化されており、今後、停車時に車両エンジンを停止する車両が増加する傾向にある。
【０００３】
ところで、車両用空調装置においては、冷凍サイクルの圧縮機を車両エンジンにより駆動しているので、上記エコラン車においては信号待ち等で停車して、車両エンジンが停止される毎に、圧縮機も停止して冷房用蒸発器の温度が上昇し、車室内への吹出空気温度が上昇するので、乗員の冷房フィーリングを損なうという不具合が発生する。
【０００４】
そこで、車両エンジン（圧縮機）の稼働時に蓄冷される蓄冷手段を備え、車両エンジン（圧縮機）が停止して蒸発器の冷却作用が停止したときには蓄冷手段の蓄冷熱量を使用して車室内への吹出空気を冷却できる蓄冷式の車両用空調装置の必要性が高まっている。
【０００５】
この種の蓄冷式の車両用空調装置として、従来、特開２０００−３１３２２６号公報に記載されたものが知られている。この従来技術では、図２２に示すように車両エンジンにより駆動される圧縮機１を有する空調用冷凍サイクルＲにおいて、車室内への吹出空気を冷却する蒸発器８と並列に蓄冷材４０ａを内蔵する蓄冷熱交換器４０を設けている。
【０００６】
そして、車両エンジン（圧縮機１）の稼働時に蓄冷を行う時は電磁弁４１を開弁して、膨張弁７により減圧された低圧冷媒を蒸発器８と蓄冷熱交換器４０に並列に流して蓄冷材４０ａを冷却し、蓄冷材４０ａへの蓄冷を行う。
【０００７】
そして、車両エンジンの停止により圧縮機１が停止した時には電動ポンプ４２を作動させて、蓄液タンク４３→電磁弁４１→電動ポンプ４２→蓄冷熱交換器４０→蒸発器８→蓄液タンク４３の閉回路にて冷媒を循環させる。蒸発器８で蒸発した気相冷媒を蓄冷熱交換器４０において蓄冷材４０ａの蓄冷熱量により凝縮し、この凝縮後の液冷媒を蒸発器８に循環させる。これにより、蒸発器８の冷却作用を圧縮機１の停止時にも続行して車室内の冷房機能を発揮できるようにしている。
【０００８】
また、上記従来技術では、車両エンジンの停止（停車）直後、すなわち、放冷冷房モードの始動直後に、蓄液タンク４３内の液冷媒を電動ポンプ４２が吸入するので、電動ポンプ４２の稼働初期にポンプ吸入側が液冷媒で満たされ、電動ポンプ４２の空転を防止できる。
【０００９】
【発明が解決しようとする課題】
ところで、上記従来技術において、蒸発器８の入口側に蓄液タンク４３を配置し、この蒸発器８および蓄液タンク４３と並列に電動ポンプ４２および蓄冷熱交換器４０を接続する冷媒回路構成としているので、これらの機器の間に３方分岐配管４４を介在し、蓄液タンク４３は３方分岐配管４４のうち蒸発器８側の分岐に接続し、電動ポンプ４２および蓄冷熱交換器４０は、３方分岐配管４４のうち反蒸発器側の分岐に接続せざるを得ない。これに加え、蓄液タンク４３と蓄冷熱交換器４０との間には冷媒流路切替用の電磁弁４１を介在する必要がある。
【００１０】
この結果、比較的大きな容積を占める蓄液タンク４３と蓄冷熱交換器４０を必然的に別体にて構成する必要があり、また、電動ポンプ４２も蓄液タンク４３と別体に構成する必要がある。そのため、電動ポンプ４２および蓄冷熱交換器４０と蓄液タンク４３とでそれぞれ専用の車両搭載スペースが必要となって、空調装置の車両搭載性が悪化する。
【００１１】
また、上記従来技術では蓄冷熱交換器４０側の冷媒通路に電磁弁４１を設置して、車両エンジン（圧縮機）の稼働時において冷房能力が不足するときは電磁弁４１を閉じて蓄冷熱交換器４０への冷媒循環を停止し、冷房能力に余裕があるときのみに電磁弁４１を開いて蓄冷熱交換器４０側に低圧冷媒を循環して蓄冷材４０ａへの蓄冷を行うようにしている。
【００１２】
従って、上記従来技術によると、蓄冷熱交換器４０側の冷媒通路開閉用の電磁弁４１が必須となる。これに加え、冷房能力の不足状態、余裕状態等を判定して電磁弁４１を開閉する制御機構も必須となる。その結果、蓄冷機能追加のために製品コストが大幅に上昇してしまうという不具合がある。
【００１３】
更に、上記従来技術において、停車時の放冷冷房モードでは、蒸発器８で蒸発した気相冷媒が蓄冷熱交換器４０内に送り込まれ、蓄冷材４０ａにより冷却され凝縮する。その凝縮後の液冷媒が蓄冷熱交換器４０内に溜まって、この貯留液冷媒の中に蓄冷材４０ａが浸漬される。この結果、蓄冷熱交換器４０内に流入する気相冷媒と蓄冷材４０ａとが接する伝熱面積が減少し、気相冷媒の凝縮能力が低下する。従って、放冷冷房モードにおける蒸発器８への液冷媒供給流量が減少して、放冷冷房能力の低下をきたす。
【００１４】
なお、上記不具合を解消するために、蓄冷熱交換器４０を蒸発器８の上方に配置して、蓄冷熱交換器４０内の液冷媒を重力にて蒸発器８に供給することを検討してみたが、車両においては、蒸発器８を内蔵する空調室内ユニット２０を車室内の計器盤（インパネ）内側等の狭隘なスペース内に搭載しなければならないという搭載上の制約がある。このため、蓄冷熱交換器４０を蒸発器８の上方に配置することは現実的にはほとんど実施できず、有効な対策といえない。
【００１５】
本発明は上記点に鑑みて、蓄冷式の車両用空調装置において車両搭載スペースを縮小することを第１の目的とする。
【００１６】
また、本発明は、蓄冷式の車両用空調装置において、電磁弁による冷媒通路の開閉機能を必要とすることなく、冷房能力および蓄冷機能を良好に発揮できるようにすることを第２の目的とする。
【００１７】
また、本発明は、蓄冷式の車両用空調装置において、放冷冷房モードにおける蓄冷熱交換器での気相冷媒の凝縮能力を向上することを第３の目的とする。
【００１８】
【課題を解決するための手段】
本発明は上記目的を達成するために案出されたもので、請求項１に記載の発明では、車両エンジン（４）により駆動される圧縮機（１）と、圧縮機（１）から吐出された高圧冷媒の放熱を行う高圧側熱交換器（６）と、高圧側熱交換器（６）を通過した冷媒を減圧する減圧手段（７、７０）と、減圧手段（７、７０）により減圧された低圧冷媒を蒸発させて車室内へ送風される空気を冷却する蒸発器（８）と、蒸発器（８）と直列に設けられ、圧縮機（１）の稼働時に、低圧冷媒により冷却される蓄冷材（１１ａ’）を有する蓄冷熱交換器（１１）と、少なくとも蓄冷熱交換器（１１）および液冷媒循環用ポンプ手段（１５）を一体に内蔵するタンク部材（１０）とを備え、
タンク部材（１０）の下部に液冷媒を溜める液冷媒タンク部（１０ａ）を一体に形成し、車両エンジン（４）が停止して圧縮機（１）が停止したときには、液冷媒タンク部（１０ａ）の液冷媒をポンプ手段（１５）により蒸発器（８）に導入し、蒸発器（８）で蒸発した気相冷媒を蓄冷熱交換器（１１）に導入して蓄冷材（１１ａ’）の蓄冷熱により冷却して凝縮することを特徴とする。
【００１９】
これによると、蓄冷熱交換器（１１）を車室内への送風空気を冷却する蒸発器（８）と直列に設けているから、圧縮機（１）の稼働時には圧縮機（１）の作動により蓄冷熱交換器（１１）と蒸発器（８）との直列通路を通して常に冷媒を流して、蒸発器（８）による冷房能力の発揮と、蓄冷熱交換器（１１）の蓄冷材（１１ａ’）への蓄冷を行うことができる。
【００２０】
そのため、蓄冷式の車両用空調装置において、電磁弁による冷媒通路の開閉機能を必要とすることなく、冷房能力および蓄冷機能を良好に発揮できる。また、車両エンジン（４）が停止して圧縮機（１）が停止したときには、タンク部材（１０）下部の液冷媒を液冷媒循環用ポンプ手段（１５）により蒸発器（８）に導入するとともに、蒸発器（８）で蒸発した気相冷媒を蓄冷熱交換器（１１）の蓄冷熱を利用して冷却、液化できるので、蒸発器（８）への液冷媒の供給を継続して冷房機能の発揮を継続できる。
【００２１】
しかも、蓄冷熱交換器（１１）を蒸発器（８）と直列に設けて、蓄冷熱交換器（１１）および液冷媒循環用ポンプ手段（１５）を、液冷媒タンク機構をなすタンク部材（１０）に一体に内蔵するから、従来技術の蓄冷熱交換器、電動ポンプおよび蓄液タンクに相当する部分を１つのタンク部材（１０）にてコンパクトに一体化でき、車両搭載性を大幅に向上できる。
【００２２】
請求項２に記載の発明では、請求項１において、タンク部材（１０）内部のうち上部側に蓄冷熱交換器（１１）を配置し、蓄冷熱交換器（１１）の下部にポンプ手段（１５）を配置したことを特徴とする。
【００２３】
これによると、ポンプ手段（１５）が下方の液冷媒タンク部（１０ａ）側に位置し、蓄冷熱交換器（１１）がポンプ手段（１５）の上方に位置するから、圧縮機（１）の停止時、すなわち、放冷冷房モード時に蓄冷熱交換器（１１）にて凝縮した液冷媒を重力にて速やかに下方の液冷媒タンク部（１０ａ）に落下させることができる。そのため、蓄冷熱交換器（１１）の表面が液冷媒中に浸漬することがないので、蓄冷熱交換器（１１）においてその蓄冷材表面と気相冷媒とが直接、接する伝熱面積を常に確保できる。
【００２４】
これにより、気相冷媒と蓄冷材との間で効率よく熱交換を行うことができるので、蓄冷熱交換器（１１）における気相冷媒の凝縮能力を常に良好に維持できる。従って、放冷冷房能力を良好に確保できる。
【００２５】
また、請求項２によれば、液冷媒タンク部（１０ａ）を下部に一体形成したタンク部材（１０）内部の上部側に蓄冷熱交換器（１１）を配置するだけで、蓄冷熱交換器（１１）自体を蒸発器（９）の上方側に配置するという必要性はない。そのため、空調装置の車両搭載上、配置レイアウトの自由度が増して非常に有利である。
【００２６】
請求項３に記載の発明では、請求項２において、ポンプ手段（１５）を液冷媒タンク部（１０ａ）の液冷媒中に浸漬するように配置したことを特徴とする。
【００２７】
これにより、液冷媒タンク部（１０ａ）の容積を有効利用してポンプ手段（１５）を配置でき、タンク部材（１０）全体の体格をより一層小型化できる。
【００２８】
しかも、ポンプ手段（１５）を液冷媒中に浸漬することにより、車両が何時停車しても、ポンプ手段（１５）の駆動直後から即座に液冷媒を蒸発器（８）に供給できるので、停車直後から放冷冷房の機能を有効に発揮できる。
【００２９】
請求項４に記載の発明では、請求項１ないし３のいずれか１つにおいて、ポンプ手段（１５）の吐出側を蒸発器（８）の入口側に接続する出口通路部（１４）をタンク部材（１０）内部に配置し、出口通路部（１４）の途中に接続口（１４ａ）を開口し、接続口（１４ａ）にタンク部材（１０）内部空間から出口通路部（１４）内への一方向のみに冷媒の流れを許容する第１逆止弁（１３）を配置したことを特徴とする。
【００３０】
これにより、停車時の放冷冷房モード時にはポンプ手段（１５）の吐出圧力により第１逆止弁（１３）が閉弁して、ポンプ手段（１５）により吐出される液冷媒を出口通路部（１４）を通して蒸発器（８）の入口側に供給できる。
【００３１】
また、車両走行時の通常冷房・蓄冷モード時には、圧縮機（１）の作動による冷媒流れによって、第１逆止弁（１３）に順方向の冷媒圧力が作用して第１逆止弁（１３）が開弁し、タンク部材（１０）内の低圧冷媒を蒸発器（８）の入口側に導入できる。
【００３２】
請求項５に記載の発明では、請求項４において、圧縮機（１）の稼働時に、タンク部材（１０）内部から第１逆止弁（１３）に吸入される冷媒の吸入開口端（１３ｂ、１３ｇ）を蓄冷熱交換器（１１）の下端部よりも上方に配置したことを特徴とする。
【００３３】
これにより、タンク部材（１０）内部において冷媒の吸入開口端（１３ｂ、１３ｇ）の部位まで液冷媒を溜めることができる。すなわち、蓄冷熱交換器（１１）の下端部よりも上方の位置まで液冷媒を溜めることができる。よって、蓄冷熱交換器（１１）の配置スペースをも利用して液溜め機能を発揮できるので、蓄冷熱交換器（１１）の下方の液溜め空間を大幅に縮小でき、タンク部材（１０）を小型化できる。この結果、タンク部材（１０）を含む蓄冷ユニットの車両搭載性を向上できる。
【００３４】
請求項６に記載の発明のように、請求項５において、第１逆止弁（１３）を蓄冷熱交換器（１１）の下端部よりも上方に配置すれば、冷媒の吸入開口端（１３ｂ、１３ｇ）を第１逆止弁（１３）それ自体の配置にて蓄冷熱交換器（１１）の下端部よりも上方に配置させることができる。
【００３５】
請求項７に記載の発明のように、請求項５において、第１逆止弁（１３）を蓄冷熱交換器（１１）の下方側に配置し、第１逆止弁（１３）の入口（１３ｂ）と吸入開口端（１３ｇ）との間を配管（１３ｆ）により接続することにより、吸入開口端（１３ｇ）を蓄冷熱交換器（１１）の下端部よりも上方に配置してもよい。
【００３６】
請求項８に記載の発明では、請求項１ないし３のいずれか１つにおいて、圧縮機（１）の稼働時に、タンク部材（１０）内部から吸入した冷媒を蒸発器（８）の入口側に導入する冷媒通路（１３、１４）の吸入開口端（１３ｂ、１３ｇ）を蓄冷熱交換器（１１）の下端部よりも上方に配置したことを特徴とする。
【００３７】
これにより、請求項５と同様に蓄冷熱交換器（１１）の下端部よりも上方の位置まで液冷媒を溜めることができる。よって、蓄冷熱交換器（１１）の下方の液溜め空間を大幅に縮小でき、タンク部材（１０）を小型化できる。この結果、タンク部材（１０）を含む蓄冷ユニットの車両搭載性を向上できる。
【００３８】
請求項９に記載の発明では、請求項５ないし８のいずれか１つにおいて、圧縮機（１）の稼働時に、蓄冷熱交換器（１１）の上方空間に流入した冷媒が蓄冷熱交換器（１１）の上方から下方へと流れ、蓄冷熱交換器（１１）の下方部にて冷媒がＵターンして吸入開口端（１３ｂ、１３ｇ）に吸入されるようにしたことを特徴とする。
【００３９】
ところで、請求項５ないし８によると、蓄冷熱交換器（１１）の下側部分が液冷媒中に浸漬するようになるので、この液冷媒中への浸漬に基づく伝熱性能の低下が懸念される。しかし、請求項９では、圧縮機（１）の稼働時（蓄冷時）に冷媒が蓄冷熱交換器（１１）の上方から下方へと流れ、蓄冷熱交換器（１１）の下方部にて冷媒がＵターンして吸入開口端（１３ｂ、１３ｇ）に吸入されるので、蓄冷熱交換器（１１）の下側部分に接している液冷媒を蓄冷熱交換器（１１）の上方から下方へと流れる冷媒流により常に流動、撹拌できる。これにより、蓄冷熱交換器（１１）下側の液冷媒浸漬部分における伝熱性能の低下を抑制できる。
【００４０】
請求項１０に記載の発明では、請求項９において、吸入開口端（１３ｂ、１３ｇ）の周囲を仕切る仕切り部材（１１０）を有し、この仕切り部材（１１０）に蓄冷熱交換器（１１）の下方部に開口する開口部（１１３）を形成し、この開口部（１１３）から蓄冷熱交換器（１１）の下方部の冷媒を取り入れて吸入開口端（１３ｂ、１３ｇ）に吸入させることを特徴とする。
【００４１】
これによると、仕切り部材（１１０）の仕切り作用によって、請求項９におけるＵターン冷媒流れを良好に形成できる。
【００４２】
請求項１１に記載の発明では、請求項５ないし１０のいずれか１つにおいて、車両エンジン（４）が停止して圧縮機（１）が停止したときに、蓄冷熱交換器（１１）にて凝縮する冷媒の凝縮量よりもポンプ手段（１５）による液冷媒循環流量が多くなるようにポンプ手段（１５）の吐出能力を設定することを特徴とする。
【００４３】
ところで、請求項５ないし１０によると、蓄冷熱交換器（１１）の下側部分が液冷媒中に浸漬するようになるので、圧縮機（１）の停止時（放冷時）にこの液冷媒中への浸漬に基づく伝熱性能の低下が懸念される。しかし、請求項１０では、ポンプ手段（１５）の吐出能力を上記のごとく設定することにより、圧縮機（１）の停止時（放冷時）における液冷媒の液面を蓄冷熱交換器（１１）の下端部より下方へ引き下げることができる。
【００４４】
これにより、蒸発器出口から還流する気相冷媒を蓄冷熱交換器（１１）全体で冷却して凝縮させることができる。従って、放冷能力の低下を防止できる。
【００４５】
請求項１２に記載の発明では、請求項１ないし１１のいずれか１つにおいて、減圧手段は、蒸発器（８）の出口冷媒の過熱度に応じて冷媒流量を調節する膨張弁（７）であり、蓄冷熱交換器（１１）を蒸発器（８）の冷媒入口側に設けることを特徴とする。
【００４６】
ところで、蓄冷熱交換器（１１）において蓄冷材（１１ａ’）への蓄冷が完了すると、低圧冷媒は蓄冷熱交換器（１１）においてほとんど吸熱することなく素通りするようになるが、もし、蓄冷熱交換器（１１）を蒸発器（８）の冷媒出口側に設けると、蒸発器出口冷媒が蓄冷完了した蓄冷材（１１ａ’）により冷却されてしまい、膨張弁（７）による冷媒流量調節を適切に行うことができない事態が生じる。
【００４７】
しかし、請求項１２によると、蓄冷熱交換器（１１）を蒸発器（８）の冷媒入口側に設けているから、膨張弁（７）は蓄冷熱交換器（１１）を設けていない通常のサイクルと同様に蒸発器出口冷媒の過熱度に応じて冷媒流量を適切に調節できる。
【００４８】
請求項１３に記載の発明では、請求項１２において、膨張弁（７）の出口からタンク部材（１０）への冷媒流入部（１２）、および蒸発器（８）の出口からタンク部材（１０）への冷媒流入部（１６）を蓄冷熱交換器（１１）の上部に配置したことを特徴とする。
【００４９】
これにより、車両走行時の通常冷房・蓄冷モード時には膨張弁（７）の出口からの低圧冷媒を蓄冷熱交換器（１１）の上部から下方へ重力方向に沿ってスムースに流すことができる。同様に、停車時の放冷冷房モード時にも、蒸発器（８）の出口からの気相冷媒を蓄冷熱交換器（１１）の上部から下方へ重力方向に沿って流すことができるので、蓄冷熱交換器（１１）表面にて冷却、凝縮した液冷媒を重力により下方へスムースに落下できる。
【００５０】
請求項１４に記載の発明では、請求項１３において、蒸発器（８）の出口からの冷媒流入部（１６）に、蒸発器（８）の出口からタンク部材（１０）への一方向のみに冷媒の流れを許容する第２逆止弁（１８）を配置したことを特徴とする。
【００５１】
これにより、停車時の放冷冷房モード時に蒸発器（８）出口からの冷媒の圧力が第２逆止弁（１８）に順方向に作用して第２逆止弁（１８）が開弁するので、蒸発器（８）出口からの冷媒を蓄冷熱交換器（１１）の上部へ流入させることができる。一方、車両走行時の通常冷房・蓄冷モード時にはタンク部材（１０）内の冷媒圧力が第２逆止弁（１８）に逆方向に作用して第２逆止弁（１８）が閉弁するので、タンク部材（１０）内の冷媒が直接、蒸発器（８）出口側に流出することを防止できる。
【００５２】
請求項１５に記載の発明では、車両エンジン（４）により駆動される圧縮機（１）と、圧縮機（１）から吐出された高圧冷媒の放熱を行う高圧側熱交換器（６）と、高圧側熱交換器（６）を通過した冷媒を減圧する減圧手段（７０）と、減圧手段（７０）により減圧された低圧冷媒を蒸発させて車室内へ送風される空気を冷却する蒸発器（８）と、蒸発器（８）の冷媒出口側に配置され、液冷媒を溜める液冷媒タンク部（１０ａ）を下部に一体に形成するタンク部材（１０）とを備え、タンク部材（１０）の内部にて蒸発器（８）出口の低圧冷媒の気液を分離して、気相冷媒を圧縮機（１）の吸入側に導出するようになっており、
圧縮機（１）の稼働時に、蒸発器（８）通過後の低圧冷媒により冷却される蓄冷材（１１ａ’）を有する蓄冷熱交換器（１１）、および液冷媒循環用ポンプ手段（１５）を少なくともタンク部材（１０）に一体に内蔵し、車両エンジン（４）が停止して圧縮機（１）が停止したときには、液冷媒タンク部（１０ａ）の液冷媒をポンプ手段（１５）により蒸発器（８）に導入し、蒸発器（８）で蒸発した気相冷媒を蓄冷熱交換器（１１）に導入して蓄冷材（１１ａ’）の蓄冷熱により冷却して凝縮することを特徴とする。
【００５３】
請求項１５におけるタンク部材（１０）は一般にアキュムレータと称される冷媒の気液分離器の機能を発揮するものであって、これにより、減圧手段として膨張弁（７）を使用しなくても圧縮機（１）への液冷媒戻り、ひいては液圧縮を防止できる。このように減圧手段として膨張弁（７）を使用しない場合は、蓄冷熱交換器（１１）を蒸発器（８）の冷媒出口側に設けてもサイクルの冷媒流量調節作用に支障は生じない。
【００５４】
また、蓄冷熱交換器（１１）を通過した低圧冷媒がタンク部材（１０）内部を通過して圧縮機（１）に吸入されるから、蓄冷熱交換器（１１）での冷却作用により低圧冷媒が液化しても、その液冷媒はタンク部材（１０）下部の液冷媒タンク部（１０ａ）内に溜めることができる。
【００５５】
そして、蒸発器（８）の冷媒流路での圧力損失分だけ、蒸発器（８）の冷媒出口側の方が冷媒入口側よりも低圧冷媒温度が低下するので、低圧冷媒温度と蓄冷材（１１ａ’）との温度差が拡大して、蓄冷材（１１ａ’）を効率よく冷却できる。
【００５６】
しかも、請求項１５によると、アキュムレータ機能を果たすタンク部材（１０）内へ蓄冷熱交換器（１１）およびポンプ手段（１５）を一体化し、かつ、タンク部材（１０）下部に液冷媒タンク部（１０ａ）を一体形成することにより、請求項１と同様に車両搭載性の向上を図ることができる。
【００５７】
請求項１６に記載の発明では、請求項１５において、タンク部材（１０）内部のうち上部側に蓄冷熱交換器（１１）を配置し、蓄冷熱交換器（１１）の下部にポンプ手段（１５）を配置することを特徴とする。
【００５８】
これにより、アキュムレータ機能を果たすタンク部材（１０）を用いるものにいて、請求項２と同様の効果を発揮できる。
【００５９】
請求項１７に記載の発明では、請求項１６において、ポンプ手段（１５）を液冷媒タンク部（１０ａ）の液冷媒中に浸漬するように配置したことを特徴とする。
【００６０】
これにより、請求項３と同様の効果を発揮できる。
【００６１】
請求項１８に記載の発明では、請求項１５ないし１７のいずれか１つにおいて、蒸発器（８）の出口からタンク部材（１０）への冷媒流入部（１２０）を蓄冷熱交換器（１１）の上部に配置したことを特徴とする。
【００６２】
これにより、蒸発器（８）出口からの冷媒を蓄冷熱交換器（１１）の上部から下方へと重力方向に沿ってスムースに流すことができる。
【００６３】
請求項１９に記載の発明では、請求項１５ないし１８のいずれか１つにおいて、ポンプ手段（１５）の吐出側を蒸発器（８）の入口側に接続する出口通路部（１４２）を備え、出口通路部（１４２）にポンプ手段（１５）から蒸発器（８）の入口側への一方向のみに冷媒の流れを許容する逆止弁（１８）を配置したことを特徴とする。
【００６４】
これにより、停車時の放冷冷房モード時にポンプ手段（１５）の吐出圧力が逆止弁（１８）に順方向に作用して逆止弁（１８）が開弁するので、ポンプ手段（１５）の吐出液冷媒を出口通路部（１４２）を通して蒸発器（８）の入口側に供給できる。一方、車両走行時の通常冷房・蓄冷モード時には蒸発器（８）の入口側の冷媒圧力が逆止弁（１８）に逆方向に作用して逆止弁（１８）が閉弁するので、蒸発器（８）の入口側冷媒が、アキュムレータ機能を果たすタンク部材（１０）内に直接、流入することを防止できる。
【００６５】
上述した請求項４の第１逆止弁（１３）、請求項１４の第２逆止弁（１８）および請求項１９の逆止弁（１８）は電磁弁に比して大幅に低コストで小型なものであり、実用上有利である。
【００６６】
請求項２０に記載の発明では、車両エンジン（４）により駆動される圧縮機（１）と、減圧手段（７、７０）により減圧された低圧冷媒を蒸発させて車室内へ送風される空気を冷却する蒸発器（８）とを包含する冷凍サイクル（Ｒ）を備える車両用空調装置に適用される蓄冷熱交換器であって、冷凍サイクル（Ｒ）の冷媒が流れるチューブ（１１ｅ）と、チューブ（１１ｅ）に熱的に一体に結合され、チューブ（１１ｅ）の拡大伝熱面を構成するフィン（１１ｆ）と、チューブ（１１ｅ）とフィン（１１ｆ）との結合体を収納するシェル（１１ｄ）と、シェル（１１ｄ）内に収納され、圧縮機（１）の稼働時にはチューブ（１１ｅ）内を通過する低温冷媒により冷却されて蓄冷を行い、圧縮機（１）の停止時には、蒸発器（８）で蒸発した気相冷媒を蓄冷熱により冷却して凝縮する蓄冷材（１１ａ’）とを備え、この蓄冷材（１１ａ’）をフィン（１１ｆ）の伝熱面相互間に薄膜状に充填することを特徴とする。
【００６７】
このように、フィン（１１ｆ）の伝熱面相互間に蓄冷材（１１ａ’）を薄膜状に充填する蓄冷熱交換器構成であると、蓄冷材（１１ａ’）の熱伝導率が小さくても、フィン（１１ｆ）と蓄冷材（１１ａ’）との間で効率よく熱交換を行うことができる。その結果、後述の図１７に示す本発明者の比較検討から明白なように、蓄冷材（１１ａ’）を円筒状やボール状の容器内に充填する場合に比較して、蓄冷熱交換器を大幅に小型化できる。
【００６８】
請求項２１に記載の発明では、請求項２０において、チューブ（１１ｅ）は上下方向に配置され、冷媒がチューブ（１１ｅ）を上方から下方へと流れることを特徴とする。
【００６９】
これによると、圧縮機停止時（放冷時）に気相冷媒が蓄冷材（１１ａ’）により冷却されてチューブ（１１ｅ）内で凝縮する際に、チューブ（１１ｅ）内を冷媒が上方から下方へと流れるので、凝縮液を冷媒流れに沿って重力により速やかにチューブ外へ排出することができる。従って、チューブ（１１ｅ）内面での凝縮液膜を常に薄い状態に維持して放冷時の伝熱性能を良好に維持できる。
【００７０】
請求項２２に記載の発明のように、請求項２０または２１において、フィン（１１ｆ）は、具体的には所定のフィンピッチにて略平行に配置された平板状フィンで構成できる。
【００７１】
請求項２３に記載の発明のように、請求項２２に記載の平板状フィン（１１ｆ）は、より具体的には、所定のフィンピッチにて積層された複数枚のフィンにより構成される。
【００７２】
請求項２４に記載の発明のように、請求項２２において、チューブ（１１ｅ）を円管状とし、平板状フィン（１１ｆ）を、チューブ（１１ｅ）の外周面上に螺旋状に連続して一体成形してもよい。
【００７３】
これによると、フィンを予めチューブ外周面上に螺旋状に一体成形しておくことができるので、熱交換器の組付作業を簡略化できる。
【００７４】
請求項２５に記載の発明では、請求項２２ないし２３のいずれか１つにおいて、フィンピッチは、０．５ｍｍ〜２．０ｍｍの範囲に設定されていることを特徴とする。
【００７５】
本発明者の検討によると、フィンピッチを上記範囲に設定することにより、蓄冷熱交換器の伝熱性能の確保と蓄冷熱交換器の小型化とを良好に達成できる。
【００７６】
請求項２６に記載の発明では、請求項２０ないし２５のいずれか１つにおいて、フィン（１１ｆ）に蓄冷材（１１ａ’）の体積変化に伴う移動を許容する貫通穴（１１ｎ）を備えることを特徴とする。
【００７７】
ところで、圧縮機稼働時（蓄冷時）に蓄冷材（１１ａ’）が液相から固相へ相変化する際は蓄冷材（１１ａ’）の体積が減少するが、請求項２６によると、貫通穴（１１ｎ）を通してフィン外部からフィン間に蓄冷材（１１ａ’）を容易に補給できる。
【００７８】
一方、圧縮機停止時（放冷時）に蓄冷材（１１ａ’）が固相から液相へ相変化する際は蓄冷材（１１ａ’）の体積が増加するが、貫通穴（１１ｎ）を通してフィン間からフィン外部へ蓄冷材（１１ａ’）を容易に押し出すことができる。
【００７９】
以上のように蓄冷材（１１ａ’）の体積変化に伴う蓄冷材（１１ａ’）の移動を容易に行うことができるので、蓄冷材（１１ａ’）の体積変化に起因してフィン（１１ｆ）に過大な応力が発生することを回避して、蓄冷熱交換器の耐久性を向上できる。
【００８０】
請求項２７に記載の発明では、請求項２０ないし２５のいずれか１つにおいて、シェル（１１ｄ）とフィン（１１ｆ）との間に断熱用の隙間部（１１ｐ）を備えることを特徴とする。
【００８１】
ところで、シェル（１１ｄ）内壁面付近はシェル外部からの熱の侵入により蓄冷材（１１ａ’）の融点以上に温度上昇して、蓄冷材（１１ａ’）が通常は液相状態に維持される。しかも、好都合なことに、蓄冷材（１１ａ’）の熱伝導率は、固相状態よりも液相状態の方がはるかに小さい。
【００８２】
従って、請求項２７ではシェル（１１ｄ）内周部の隙間部（１１ｐ）に位置する蓄冷材（１１ａ’）を液相状態に維持して、蓄冷材自身の熱伝導率が小さいことを有効利用して、断熱作用を効果的に発揮できる。
【００８３】
その結果、特別な断熱構造を設けなくても冷熱損失を大幅に低減できる。また、断熱構造を設ける場合でも、断熱材使用量を大幅に低減できる。
【００８４】
なお、上記各手段の括弧内の符号は、後述する実施形態に記載の具体的手段との対応関係を示すものである。
【００８５】
【発明の実施の形態】
（第１実施形態）
図１は第１実施形態による車両用空調装置の冷凍サイクルＲを示す。車両用空調装置の冷凍サイクルＲは冷媒を吸入、圧縮、吐出する圧縮機１を有し、この圧縮機１には動力断続用の電磁クラッチ２が備えられている。圧縮機１には電磁クラッチ２およびベルト３を介して車両エンジン４の動力が伝達されるので、電磁クラッチ２への通電を空調用制御装置５により断続することにより圧縮機１の運転が断続される。
【００８６】
圧縮機１から吐出された高温、高圧の過熱気相冷媒は高圧側熱交換器をなす凝縮器６に流入し、図示しない冷却ファンより送風される外気と熱交換して冷却され凝縮する。凝縮器６は凝縮部６ａと、凝縮部６ａを通過した後の冷媒の気液を分離して液冷媒を溜めるとともに液冷媒を導出する受液器６ｂと、受液器６ｂからの液冷媒を過冷却する過冷却部６ｃとを一体に構成した周知のものである。
【００８７】
この過冷却部６ｃからの過冷却液冷媒は減圧手段をなす膨張弁７により低圧に減圧され、低圧の気液２相状態となる。膨張弁７は冷房用熱交換器をなす蒸発器８の出口冷媒の過熱度を調節するように弁７ａの開度（冷媒流量）を調節する温度式膨張弁である。特に、本例では、蒸発器８の出口冷媒が流れる蒸発器出口冷媒通路７ｂをボックス型のハウジング７ｃ内に構成して、蒸発器８の出口冷媒の感温機構をハウジング７ｃ内に一体構成するタイプの温度式膨張弁７を用いている。
【００８８】
蓄冷ユニット９は図１の２点鎖線枠内の機器を図２に示す１つのタンク部材１０の内部に一体的に構成しているものであって、タンク部材１０は上下方向に延びる円筒状の形状であり、その下部に低温の低圧液冷媒を溜める液冷媒タンク部１０ａを一体に構成している。
【００８９】
そして、タンク部材１０内部において、液冷媒タンク部１０ａの上方部に蓄冷熱交換器１１を構成している。この蓄冷熱交換器１１は具体的には、蓄冷材１１ａ’を封入した多数の蓄冷材容器１１ａをその容器相互間に冷媒が流通する隙間部を形成する状態で配置している。この多数の蓄冷材容器１１ａの上下両側に冷媒流通穴を有する保持板１１ｂ、１１ｃを配置し、この保持板１１ｂ、１１ｃの外周部をタンク部材１０の内壁面に固定している。
【００９０】
ここで、蓄冷材容器１１ａの形態は具体的には図３（ａ）に示す冷媒流れ方向に沿って細長く延びる円筒状からなる円筒（スティック）タイプ、図３（ｂ）に示すボールタイプ、図３（ｃ）に示すカプセルタイプのいずれでもよい。蓄冷材容器１１ａは樹脂製の薄膜状パック部材、あるいはアルミニュウム等の金属板材で形成することができる。
【００９１】
蓄冷材容器１１ａ内に封入する蓄冷材１１ａ’としては、低圧冷媒により冷却されて相変化（液相→固相）して凝固潜熱を蓄冷できる材料、すなわち、低圧冷媒温度よりも高い温度で凝固する材料を選択する。
【００９２】
ここで、低圧冷媒温度は蒸発器８でのフロスト防止のために、通常３〜４℃程度の温度に制御され、また、冷房時における車室内吹出空気温度の目標上限温度は冷房フィーリングの確保、蒸発器８からの悪臭防止等のために、通常は１２℃〜１５°程度の温度に設定される。
【００９３】
従って、蓄冷材１１ａ’としては、凝固点が上記低圧冷媒温度と冷房時吹出空気温度の目標上限温度との間に位置する材料が好ましく、具体的には、凝固点が６℃〜８℃程度のパラフィンが最適である。もちろん、低圧冷媒温度を０℃以下に制御すれば、蓄冷材１１ａ’として水（氷）を使用することもできる。
【００９４】
蓄冷材１１ａ’の蓄冷状態（凝固状態）を維持するためには、タンク部材１０内部を蓄冷材１１ａ’の凝固点以下の低温状態に維持する必要があるため、タンク部材１０は断熱タンクとして構成する必要がある。従って、タンク部材１０は断熱性に優れた樹脂タンク、あるいは金属タンク表面に断熱材を貼り付けたもの等を用いる。
【００９５】
なお、蓄冷熱交換器１１をシェルアンドチューブタイプの熱交換器として構成してもよく、その場合はシェル（タンク）内部に配置されるチューブにサイクル低圧冷媒を流通させ、そして、シェル（タンク）内部においてチューブの外側空間に蓄冷材１１ａ’を充填してサイクル低圧冷媒により冷却すればよい。
【００９６】
次に、蓄冷ユニット９と冷凍サイクル冷媒通路との接続関係を説明すると、タンク部材１０の上面には、膨張弁７の弁部７ａを通過して減圧された低温の低圧冷媒が流入する入口パイプ１２が配置してある。この入口パイプ１２は冷媒流入部を構成するものであって、この入口パイプ１２からタンク部材１０内において蓄冷熱交換器１１の上面部に低温の低圧冷媒が流入する。
【００９７】
タンク部材１０内において蓄冷熱交換器１１の下面部には第１逆止弁１３が配置してある。この第１逆止弁１３の入口１３ｂは蓄冷熱交換器１１の下方空間に常時連通しており、第１逆止弁１３の弁体１３ａに対して入口１３ｂから出口１３ｃの方向に冷媒圧力が作用するときは弁体１３ａが弁座部１３ｄから開離して開弁状態となる。逆に、弁体１３ａに対して出口１３ｃから入口１３ｂの方向に冷媒圧力が作用するときは弁体１３ａが弁座部１３ｄに圧着して閉弁状態となる。ストッパ１３ｅは弁体１３ａの全開位置を規定するものである。
【００９８】
タンク部材１０の中心部には出口通路部をなす出口パイプ１４が蓄冷熱交換器１１の中心部を貫通して上下方向に延びるように配置されている。この出口パイプ１４の上端側はタンク部材１０の上面を貫通してタンク外部へ取り出され、図１に示すように蒸発器８の入口部に接続される。
【００９９】
一方、出口パイプ１４の下端側は液冷媒タンク部１０ａの液冷媒貯留領域まで垂下しており、そして、出口パイプ１４の下端部に液冷媒循環用のポンプ手段をなす電動ポンプ１５が設けてある。この電動ポンプ１５はその底面部側に吸入口１５ａを配置し、この吸入口１５ａから液冷媒タンク部１０ａの液冷媒を吸入して出口パイプ１４を通して蒸発器８に循環させるものである。
【０１００】
出口パイプ１４には上下方向の中間部に接続口１４ａが開口し、この接続口１４ａに第１逆止弁１３の出口１３ｃを接続している。従って、膨張弁７の弁部７ａの出口通路から入口パイプ１２、蓄冷熱交換器１１、第１逆止弁１３、および出口パイプ１４を経て蒸発器８の入口に至る冷媒通路が形成され、蓄冷熱交換器１１は蒸発器８の入口側通路に直列に設けられている。
【０１０１】
また、タンク部材１０の上面には、蒸発器８出口からの冷媒をタンク部材１０内に流入させる冷媒流入部をなす冷媒戻しパイプ１６が設けてある。この冷媒戻しパイプ１６の一端側（上端側）は蒸発器８の出口冷媒配管１７に接続してあり、冷媒戻しパイプ１６の他端側（下端側）はタンク部材１０の上面を貫通してタンク部材１０内に配置された第２逆止弁１８に接続される。
【０１０２】
より具体的に説明すると、蒸発器８の出口冷媒配管１７は膨張弁７内部の蒸発器出口冷媒通路７ｂに接続されるものであり、この蒸発器出口冷媒通路７ｂよりも上流側部位にて冷媒戻しパイプ１６の一端が出口冷媒配管１７に接続される。また、タンク部材１０内の空間の最上部に第２逆止弁１８が配置され、第２逆止弁１８の入口１８ｂが冷媒戻しパイプ１６の他端側（下端側）に接続される。第２逆止弁１８の出口１８ｃは蓄冷熱交換器１１の上面部に対向配置されている。
【０１０３】
第２逆止弁１８は第１逆止弁１３と同様のものであり、第２逆止弁１８の弁体１８ａに対して入口１８ｂから出口１８ｃの方向に冷媒圧力が作用するときは弁体１８ａが弁座部１８ｄから開離して開弁状態となる。逆に、弁体１８ａに対して出口１８ｃから入口１８ｂの方向に冷媒圧力が作用するときは弁体１８ａが弁座部１８ｄに圧着して閉弁状態となる。ストッパ１８ｅは弁体１８ａの全開位置を規定するものである。
【０１０４】
なお、本例では、蓄冷ユニット９のタンク部材１０の上面に膨張弁７を配置して、膨張弁７も蓄冷ユニット９の一部分として一体化し、膨張弁７と蓄冷ユニット９を一体状態にて車両に搭載するようにしてある。
【０１０５】
蓄冷ユニット９はタンク部材１０内部の低温状態を維持するためにはタンク部材１０内部への熱の侵入をできるだけ抑制した方が良い。そのためには、蓄冷ユニット９を車室内、例えば、車室内前部の計器盤内側等に設置した方が良い。しかし、車室内のスペース的制約から車室内に蓄冷ユニット９の搭載スペースを確保できない場合は、蓄冷ユニット９を車室外、例えば、エンジンルーム等に設置することになる。
【０１０６】
図４は空調室内ユニット２０を示すものであり、空調室内ユニット２０は通常、車室内前部の計器盤内側に搭載される。空調室内ユニット２０の空調ケース２１は車室内へ向かって送風される空気の通路を構成するものであり、この空調ケース２１内に蒸発器８が設置されている。
【０１０７】
空調ケース２１において、蒸発器８の上流側には送風機２２が配置され、送風機２２には遠心式送風ファン２２ａと駆動用モータ２２ｂが備えられている。送風ファン２２ａの吸入側には内外気切替箱２３が配置され、この内外気切替箱２３内の内外気切替ドア２３ａにより外気（車室外空気）または内気（車室内空気）が切替導入される。
【０１０８】
空調ケース２１内で、蒸発器８の下流側にはエアミックスドア２４が配置され、このエアミックスドア２４の下流側には車両エンジン４の温水（冷却水）を熱源として空気を加熱する温水式ヒータコア２５が暖房用熱交換器として設置されている。
【０１０９】
そして、この温水式ヒータコア２５の側方（上方部）には、温水式ヒータコア２５をバイパスして空気（冷風）を流すバイパス通路２６が形成されている。エアミックスドア２４は回動可能な板状ドアであり、温水式ヒータコア２５を通過する温風とバイパス通路２６を通過する冷風との風量割合を調節するものであって、この冷温風の風量割合の調節により車室内への吹出空気温度を調節する。従って、エアミックスドア２４は車室内への吹出空気の温度調節手段を構成する。
【０１１０】
温水式ヒータコア２５からの温風とバイパス通路２６からの冷風を空気混合部２７で混合して、所望温度の空気を作り出すことができる。さらに、空調ケース２１内で、空気混合部２７の下流側に吹出モード切替部が構成されている。すなわち、車両フロントガラス内面に空気を吹き出すデフロスタ開口部２８、車室内乗員の上半身側に向けて空気を吹き出すフェイス開口部２９、および車室内乗員の足元に向けて空気を吹き出すフット開口部３０を吹出モードドア３１〜３３により開閉するようになっている。
【０１１１】
蒸発器８の温度センサ３４は空調ケース２１内で蒸発器８の空気吹出直後の部位に配置され、蒸発器吹出温度Ｔｅを検出する。ここで、蒸発器温度センサ３４により検出される蒸発器吹出温度Ｔｅは、通常の空調装置と同様に、圧縮機１の電磁クラッチ２の断続制御や、圧縮機１が可変容量型である場合はその吐出容量制御に使用され、これらのクラッチ断続制御や吐出容量制御により蒸発器８の冷却能力を調節して、蒸発器８の吹出温度を制御する。
【０１１２】
図１に示すように、空調用制御装置５には、上記の温度センサ３４の他に、空調制御のために、内気温Ｔｒ、外気温Ｔａｍ、日射量Ｔｓ、温水温度Ｔｗ等を検出する周知のセンサ群３５から検出信号が入力される。また、車室内計器盤近傍に設置される空調制御パネル３６の操作スイッチ群の操作信号も空調用制御装置５に入力される。
【０１１３】
空調制御パネル３６には乗員により手動操作される温度設定スイッチ、風量切替スイッチ、吹出モードスイッチ、内外気切替スイッチ、圧縮機１のオンオフ信号を発生するエアコンスイッチ等の種々な操作スイッチ群（図示せず）が備えられている。
【０１１４】
また、空調用制御装置５はエンジン用制御装置３７に接続されており、エンジン用制御装置３７から空調用制御装置５には車両エンジン４の回転数信号、車速信号等が入力される。
【０１１５】
エンジン用制御装置３７は周知のごとく車両エンジン４の運転状況等を検出するセンサ群３８からの信号に基づいて車両エンジン４への燃料噴射量、点火時期等を総合的に制御するものである。さらに、本実施形態の対象とするエコラン車においては、車両エンジン４の回転数信号、車速信号、ブレーキ信号等に基づいて停車状態を判定すると、エンジン用制御装置３７は、点火装置の電源遮断、燃料噴射の停止等により車両エンジン４を自動的に停止させる。
【０１１６】
また、エンジン停止後、運転者の運転操作により車両が停車状態から発進状態に移行すると、エンジン用制御装置３７は車両の発進状態をアクセル信号等に基づいて判定して、車両エンジン４を自動的に始動させる。なお、空調用制御装置５は、車両エンジン４停止後の放冷冷房モードの時間が長時間に及び、蓄冷熱交換器１１の蓄冷熱量による冷房を持続できない状態になった時、すなわち、蒸発器吹出温度Ｔｅが所定の目標上限温度まで上昇した時は、エンジン再稼働要求の信号をエンジン用制御装置３７に出力する。
【０１１７】
空調用制御装置５およびエンジン用制御装置３７はＣＰＵ、ＲＯＭ、ＲＡＭ等からなる周知の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ある。なお、空調用制御装置５およびエンジン用制御装置３７を１つの制御装置として統合してもよい。
【０１１８】
次に、上記構成において第１実施形態の作動を説明する。図５は車両走行時の通常冷房・蓄冷モード時の作動を示すものであり、この通常冷房・蓄冷モード時では車両エンジン４によって圧縮機１を駆動することにより冷凍サイクルＲが運転される。
【０１１９】
従って、圧縮機１から吐出された高圧気相冷媒が凝縮器６にて冷却され、過冷却状態の液冷媒となって膨張弁７に流入する。この膨張弁７の弁部７ａで高圧液冷媒が減圧されて低温低圧の気液２相状態となり、入口パイプ１２から蓄冷ユニット９のタンク部材１０内に流入する。この流入冷媒はタンク部材１０内において蓄冷熱交換器１１の上面部から多数の蓄冷材容器１１ａ相互間の隙間部を下方へと流れる。
【０１２０】
ここで、蓄冷熱交換器１１の下面部に位置する第１逆止弁１３の弁体１３ａに対して入口１３ｂから出口１３ｃの方向（順方向）に冷媒圧力が作用して、第１逆止弁１３が開弁するので、蓄冷熱交換器１１の下側空間が第１逆止弁１３を介して出口パイプ１４の中間部の接続口１４ａに連通する。
【０１２１】
また、通常冷房・蓄冷モード時は液冷媒循環用の電動ポンプ１５の作動が不要であるため、空調制御装置５の出力により電動ポンプ１５が停止している。このため、電動ポンプ１５が流通抵抗となり、蓄冷熱交換器１１の下側空間の冷媒が電動ポンプ１５を介して出口パイプ１４の下端部に流入する量は僅少である。
【０１２２】
従って、蓄冷熱交換器１１の下側空間の冷媒の大部分は第１逆止弁１３を介して出口パイプ１４の中間部の接続口１４ａに流入する。このとき、第２逆止弁１８の弁体１８ａに対しては出口１８ｃから入口１８ｂの方向（逆方向）に冷媒圧力が作用して、第２逆止弁１８は閉弁状態を維持する。
【０１２３】
出口パイプ１４に流入した低圧冷媒は蒸発器８の入口部に流入し、蒸発器８において空調ケース２１内の送風空気から吸熱して蒸発し、気相冷媒となる。この気相冷媒は、蒸発器８の出口冷媒配管１７および膨張弁７内部の蒸発器出口冷媒通路７ｂを経て圧縮機１に吸入され、再度圧縮される。蒸発器８にて吸熱された冷風はフェイス開口部２９等から車室内へ吹き出して車室内を冷房する。
【０１２４】
次に、通常冷房・蓄冷モード時における蓄冷ユニット９のタンク部材１０内部での冷媒の挙動をより具体的に説明すると、夏期の高外気温時に冷房を始動する場合には蒸発器８の吸い込み空気温度が４０℃以上にも及ぶ高温となり、蒸発器８の冷房熱負荷が非常に大きくなる。このような冷房高負荷条件の下では、蒸発器８の出口冷媒の過熱度が過大となり、膨張弁７の弁部７ａの開度が全開となり、冷凍サイクルの低圧圧力が上昇する。
【０１２５】
そのため、蓄冷ユニット９の蓄冷熱交換器１１に流入する低圧冷媒の温度が蓄冷熱交換器１１の蓄冷材１１ａ’の凝固点（６〜８℃程度）より高い温度となる。従って、蓄冷材１１ａ’は低圧冷媒との熱交換で凝固せず、蓄冷材１１ａ’から顕熱分を吸熱するだけである。その結果、冷房高負荷条件では低圧冷媒が蓄冷熱交換器１１にて吸熱する熱量は僅少量となる。そのため、低圧冷媒のほとんどは蓄冷熱交換器１１を持たない通常の空調装置と同様に蒸発器８にて車室内吹出空気から吸熱して蒸発する。
【０１２６】
なお、冷房高負荷時には、通常、図４の内外気切替箱２３から内気を吸入する内気モードが選択されるから、冷房始動後の時間経過により蒸発器８の吸い込み空気温度が低下し、冷房熱負荷が低下する。これにより、蒸発器８の出口冷媒の過熱度が減少するので、膨張弁７の弁部７ａの開度が減少し、冷凍サイクルの低圧圧力が低下し、低圧冷媒温度が低下する。
【０１２７】
そして、低圧冷媒温度が蓄冷熱交換器１１の蓄冷材１１ａ’の凝固点より低下すると、蓄冷材１１ａ’の凝固が開始され、低圧冷媒は蓄冷材１１ａ’から凝固潜熱を吸熱するので、蓄冷材１１ａ’からの吸熱量が増加する。しかし、蓄冷材１１ａ’がこのように凝固潜熱を蓄冷する段階に至った時点では、既に、冷房熱負荷の低下により低圧冷媒温度が十分低下し、車室内吹出空気が十分低下している。
【０１２８】
従って、蓄冷材１１ａ’への凝固潜熱の蓄冷作用によって、冷房高負荷条件における急速冷房性能（クールダウン性能）が大きく阻害されることがない。換言すると、蓄冷熱交換器１１を冷房用蒸発器８の冷媒回路に直列接続しても、冷房高負荷条件における急速冷房性能を、僅少量低下させるだけであり、良好に発揮できる。
【０１２９】
そして、冷房熱負荷が低下して蓄冷材１１ａ’が凝固する時には、サイクル内の循環冷媒流量が減少し、蓄冷ユニット９のタンク部材１０内での冷媒流速が低下して、気液２相状態の低圧冷媒の気液分離が起こりやすくなる。これにより、タンク部材１０の下部に形成されている液冷媒タンク部１０ａに液冷媒が重力により落下し、徐々に溜まっていく。
【０１３０】
図２は液冷媒タンク部１０ａに液冷媒が最大量溜まった状態を示している。すなわち、液冷媒タンク部１０ａにおける貯留液冷媒の液面が上昇して、第１逆止弁１３の設置高さに到達すると、液冷媒タンク部１０ａの液冷媒は第１逆止弁１３を通して蒸発器８に送り込まれるから、第１逆止弁１３の設置高さより貯留液冷媒の液面が上昇することはない。換言すると、第１逆止弁１３は貯留液冷媒の最大量を決める役割を果たしている。
【０１３１】
次に、信号待ち等の停車時に車両エンジン４を自動的に停止する場合について説明すると、停車時には空調作動状態（送風機２２の作動状態）であっても、車両エンジン４の停止に伴って冷凍サイクルＲの圧縮機１も強制的に停止状態となる。そこで、空調用制御装置５ではこの停車時のエンジン（圧縮機）停止状態を判定して、蓄冷ユニット９内の電動ポンプ１５に給電し、電動ポンプ１５を作動させる。
【０１３２】
これにより、タンク部材１０下部の液冷媒タンク部１０ａに溜まっている液冷媒を電動ポンプ１５が吸入して、出口パイプ１４を介して蒸発器８の入口側に液冷媒を吐出する。この電動ポンプ１５による液冷媒の吸入、吐出作用によって、第１逆止弁１３には冷媒圧力が逆方向に作用して第１逆止弁１３は閉弁する。これに反し、第２逆止弁１８には冷媒圧力が順方向に作用して第２逆止弁１８は開弁する。
【０１３３】
そのため、図６の矢印に示すように、液冷媒タンク部１０ａ→電動ポンプ１５→出口パイプ１４→蒸発器８→出口冷媒配管１７→冷媒戻しパイプ１６→第２逆止弁１８→蓄冷熱交換器１１→液冷媒タンク部１０ａからなる冷媒循環回路で冷媒が循環する。
【０１３４】
従って、蒸発器８では液冷媒タンク部１０ａからの液冷媒が送風機２２の送風空気から吸熱して蒸発するので、圧縮機停止後においても蒸発器８の冷却作用を継続でき、車室内の冷房作用を継続できる。蒸発器８で蒸発した気相冷媒の温度は蓄冷熱交換器１１の蓄冷材１１ａ’の凝固点より高いので、蓄冷材１１ａ’は気相冷媒から融解潜熱を吸熱して固相から液相に相変化（融解）する。これにより、気相冷媒は蓄冷材１１ａ’により冷却され凝縮する。この液冷媒は重力により落下して液冷媒タンク部１０ａに蓄えられる。
【０１３５】
そして、蓄冷材１１ａ’が液相に相変化していくことにより、液冷媒タンク部１０ａ内の液冷媒量が減少していくが、液冷媒タンク部１０ａ内の液冷媒が残存している間、停車時（圧縮機停止時）の車室内冷房作用を継続できる。
【０１３６】
なお、信号待ちによる停車時間は通常、１〜２分程度の短時間であるから、蓄冷材１１ａ’として、凝固点＝６℃、凝固潜熱＝２２９ｋＪ／ｋｇのパラフィンを、４２０ｇ程度用いることにより、１〜２分程度の停車時の間、車室内冷房作用を継続できることを確認している。
【０１３７】
次に、第１実施形態の作用効果を説明する。
【０１３８】
（１）前述の従来技術（特開２０００−３１３２２６号公報）では、比較的容積の大きい蓄冷熱交換器４０と蓄液タンク４３とを別体に構成する必要があり、また、蓄液タンク４３と電動ポンプ４２とを別体に構成する必要があって、車両搭載スペースが増大し、空調装置の車両搭載性が悪化するが、第１実施形態では、蓄冷熱交換器１１を蒸発器８の入口側に直列接続する冷媒回路構成とし、そして、タンク部材１０の内部に蓄冷熱交換器１１を配置するとともに、タンク部材１０の下部に液冷媒タンク部１０ａを一体に形成し、膨張弁７出口からの低圧冷媒が蓄冷熱交換器１１と熱交換した後に蒸発器８に導入されるようにしている。
【０１３９】
しかも、第１実施形態によると、電動ポンプ１５と液冷媒タンク部１０ａとの間に従来技術の３方分岐配管４４のような特別の分岐配管を設定する必要がないので、電動ポンプ１５をタンク部材１０下部の液冷媒タンク部１０ａの液冷媒中に直接、浸漬するように配置できる。
【０１４０】
以上により、従来技術の蓄冷熱交換器４０、蓄液タンク４３および電動ポンプ４２に相当する部分を１つのタンク部材１０に一体化できる。これにより、蓄冷および放冷冷房機能のための蓄冷ユニット９を極めてコンパクトに構成できる。従って、このコンパクトな１つの蓄冷ユニット９を車両空調用の一般的な冷凍サイクルに追加するだけでよく、空調装置の車両搭載性を従来技術より大幅に向上できる。
【０１４１】
（２）停車時の放冷冷房モード時に、蒸発器８の出口からの冷媒をタンク部材１０内に流入させる冷媒流入部、すなわち、冷媒戻しパイプ１６を蓄冷熱交換器１１の上部に設け、蓄冷熱交換器１１の下部に電動ポンプ１５および液冷媒タンク部１０ａを配置しているから、蓄冷熱交換器１１で凝縮した液冷媒を重力にて速やかに液冷媒タンク部１０ａに落下できる。
【０１４２】
このため、蓄冷熱交換器１１の蓄冷材容器１１ａの表面に液冷媒が淀むことがない。この結果、蓄冷熱交換器１１において気相冷媒と蓄冷材容器１１ａとが直接、接する伝熱面積を常に確保できる。
【０１４３】
これにより、放冷冷房モード時に気相冷媒と蓄冷材容器１１ａとの間の熱交換を効率よく行うことができるので、蓄冷熱交換器１１における気相冷媒の凝縮能力を常に良好に維持できる。従って、放冷冷房モード時に蒸発器８への液冷媒供給流量を良好に確保して、放冷冷房能力を良好に発揮できる。
【０１４４】
また、上記のように、蓄冷熱交換器１１をタンク部材１０内にて液冷媒タンク部１０ａの上方に配置することにより、蓄冷熱交換器１１表面での液冷媒の淀みを防止できるので、蓄冷熱交換器１１自体を蒸発器８を内蔵する空調室内ユニット２０の上方に配置するという必要性はなく、車両搭載上、配置レイアウトの自由度が増して非常に有利である。
【０１４５】
（３）タンク部材１０内において蓄冷熱交換器１１の下方に電動ポンプ１５および液冷媒タンク部１０ａを配置して、電動ポンプ１５を液冷媒タンク部１０ａの液冷媒中に直接、浸漬するように配置するから、車両が何時停車しても、放冷モード開始と同時に電動ポンプ１５はその駆動直後から直ちに液冷媒を吸入、吐出できる。従って、放冷モード時に電動ポンプ１５がガス冷媒を吸入して蒸発器８への冷媒供給流量が低下するといった不具合が発生せず、車両の停車直後から即時、放冷冷房の機能を良好に発揮できる。
【０１４６】
（４）車両走行時の通常冷房・蓄冷モード時に、膨張弁７出口からの低圧冷媒をタンク部材１０内に流入させる冷媒流入部、すなわち、入口パイプ１２をタンク部材１０の上部に設け、そして、タンク部材１０内において蓄冷熱交換器１１の下側に逆止弁１３を設けて、蓄冷熱交換器１１の下側の冷媒が逆止弁１３および出口パイプ１４を通して蒸発器８の入口側に導入されるようにしている。
【０１４７】
従って、通常冷房・蓄冷モード時においても、低圧冷媒が蓄冷熱交換器１１の上部から下部へと重力方向に沿ってスムースに冷媒が流れ、蓄冷熱交換器１１下側の逆止弁１３および出口パイプ１４を通して低圧冷媒を蒸発器８の入口側にスムースに導入できる。
【０１４８】
そして、蓄冷熱交換器１１の蓄冷完了後の余剰液冷媒は下方の液冷媒タンク部１０ａへ重力によりスムースに落下させることができる。また、液冷媒タンク部１０ａに溜まる余剰液冷媒の最大液面高さ（最大液冷媒貯留量）を前述のように蓄冷熱交換器１１下側の逆止弁１３の位置によって規定できるので、逆止弁１３の位置まで余剰液冷媒の液面高さが上昇すると、これ以後は、余剰液冷媒が気液混合状態となって蒸発器８に導入される。すなわち、液冷媒タンク部１０ａが存在しない状態と等価の状況で冷凍サイクルは作動する。
【０１４９】
（５）次に、本実施形態による「冷房用蒸発器８に対して蓄冷熱交換器１１を直列接続する」ことの有利さを従来技術との対比により詳述する。前述の従来技術（特開２０００−３１３２２６号公報）では、空調用冷凍サイクルＲにおいて蓄冷材４０ａを内蔵する蓄冷熱交換器４０を冷房用蒸発器８と並列に設けているので、蓄冷熱交換器４０の冷媒通路を冷凍サイクルの運転状況に応じて電磁弁４１により開閉することが必須となる。
【０１５０】
これに反し、本実施形態によると、冷房用蒸発器８に対して蓄冷熱交換器１１を直列接続しているから、夏期の冷房始動時のように冷房熱負荷が非常に高い条件においても、サイクル循環冷媒流量の全量が冷房用蒸発器８を通過するから、蓄冷熱交換器１１の追加により冷房用蒸発器８への循環冷媒流量が減少することはない。
【０１５１】
しかも、蓄冷熱交換器１１における蓄冷材１１ａ’の凝固点を前述のように冷房時吹出空気温度の目標上限温度（１２〜１５℃程度）よりも低い温度（６〜８℃程度）に設定することにより、冷房高熱負荷条件における低圧冷媒の温度よりも蓄冷材１１ａ’の凝固点が低い温度となる。このため、冷房高熱負荷条件では蓄冷材１１ａ’は低圧冷媒との熱交換で凝固せず、顕熱分の吸熱が僅かに行われるだけである。
【０１５２】
そのため、低圧冷媒の大部分は蓄冷熱交換器１１を持たない通常の空調装置と同様に蒸発器８にて車室内吹出空気から吸熱して蒸発する。つまり、蓄冷熱交換器１１への冷媒流れの切替のための特別の操作を行わなくても、冷房高熱負荷条件における冷房用蒸発器８の最大冷却能力を良好に発揮できる。
【０１５３】
その結果、車両走行時の通常冷房・蓄冷モードと、停車時の放冷冷房モードとの間での冷媒流れは、電磁弁に比して大幅に低コストで小型な逆止弁１３、１８によって切り替えることができる。
【０１５４】
（６）また、蓄冷熱交換器１１における蓄冷材１１ａ’の凝固が完了し、蓄冷完了状態になると、蓄冷熱交換器１１における低圧冷媒の吸熱はほとんどなくなるが、蓄冷熱交換器１１を冷房用蒸発器８の入口側に配置しているため、膨張弁７は蒸発器８の出口冷媒の過熱度を感知して冷媒流量を調節できる。従って、蓄冷完了後においても、蒸発器８の冷房熱負荷に応じた適切な冷媒流量を蒸発器８に供給できる。
【０１５５】
なお、第１実施形態において、蓄冷熱交換器１１をもし蒸発器８の出口側に配置すると、蓄冷材１１ａ’の蓄冷完了状態では蒸発器８の出口冷媒が過熱度を持っていても蒸発器８の出口冷媒が蓄冷材１１ａ’により冷却されて過熱度が小さくなってしまい、その結果、膨張弁７の開度が減少して、蒸発器８の冷房熱負荷に対して冷媒流量が過小になるという不具合が生じるが、蓄冷熱交換器１１を冷房用蒸発器８の入口側に配置することにより、このような不具合が生じない。
【０１５６】
（第２実施形態）
上記の第１実施形態では、減圧手段として膨張弁７を用い、膨張弁７により蒸発器８の出口冷媒の過熱度を調節する冷凍サイクルについて説明したが、第２実施形態は蒸発器８の出口側（圧縮機１の吸入側）にアキュムレータを配置し、このアキュムレータにおいて蒸発器出口冷媒の気液を分離して液冷媒を溜めて、気相冷媒を圧縮機１に吸入させるアキュムレータ式の冷凍サイクルに蓄冷熱交換器１１を組み合わせるものである。
【０１５７】
図７〜図１０は第２実施形態を示すもので、前述の図１、図２、図５、図６に対応するものであり、第１実施形態と同等部分には同一符号を付して説明を省略する。また、制御装置５、３７等の電気制御部は第１実施形態と同じであるので、図７〜図１０ではこの電気制御部の図示を省略している。
【０１５８】
アキュムレータ式の冷凍サイクルにおいては、蒸発器８の出口側にタンク状のアキュムレータを配置するので、第２実施形態ではこのアキュムレータに着目して蓄冷ユニット９をアキュムレータと一体に構成する。
【０１５９】
すなわち、第２実施形態では、図８に示すように蓄冷ユニット９のタンク部材１０の上面部に蒸発器８の出口からの冷媒を受け入れる入口パイプ１２０を設け、この入口パイプ１２０により蒸発器８の出口冷媒をタンク部材１０内の上部に流入させる。従って、入口パイプ１２０により蒸発器出口冷媒の流入部が構成される。
【０１６０】
一方、タンク部材１０の下部に液冷媒を溜める液冷媒タンク部１０ａを一体に形成している。蓄冷熱交換器１１は第１実施形態と同様のものであり、タンク部材１０内の上部に配置され、入口パイプ１２０からの流入冷媒が多数の蓄冷材容器１１ａ相互の隙間部を通過して下方へ流れる。
【０１６１】
タンク部材１０の内部には、第１、第２の２つの出口パイプ１４１、１４２が配置してある。第１出口パイプ１４１は通常のアキュムレータにおける出口パイプに相当するものであり、そのため、第１出口パイプ１４１はＵ状に曲げ形成され、Ｕ状の底部にオイル戻し穴１４１ａを開口し、このオイル戻し穴１４１ａから液冷媒中に含まれる圧縮機潤滑用オイルを吸い込むようになっている。
【０１６２】
また、第１出口パイプ１４１のＵ状一端部に気相冷媒吸入口１４１ｂを設け、この気相冷媒吸入口１４１ｂをタンク部材１０内の下部の液冷媒タンク部１０ａに溜まる液冷媒よりも上方の空間に開口する。これにより、タンク部材１０内の上部の気相冷媒を気相冷媒吸入口１４１ｂから第１出口パイプ１４１内に吸入するようになっている。第１出口パイプ１４１の他端側はタンク部材１０の上面部からタンク外部へ取り出して、圧縮機１の吸入側に接続するようになっている。
【０１６３】
また、第１出口パイプ１４１において、気相冷媒吸入口１４１ｂの下流側（下方側）には冷媒中の水分を吸収する乾燥剤を内蔵する乾燥剤ユニット１４１ｃが配置してある。
【０１６４】
一方、第２出口パイプ１４２は停車時の放冷冷房モード時の冷媒循環回路の出口通路部を構成するものであり、その下端部を液冷媒タンク部１０ａの液冷媒中に位置させ、第２出口パイプ１４２の下端部に液冷媒循環用ポンプ手段をなす電動ポンプ１５を設け、電動ポンプ１５の下端部の吸入口１５ａから液冷媒を吸入して第２出口パイプ１４２に吐出する。電動ポンプ１５は本例も液冷媒タンク部１０ａの液冷媒中に浸漬するように配置されている。
【０１６５】
第２出口パイプ１４２の他端側もタンク部材１０の上面部からタンク外部へ取り出してあり、第２出口パイプ１４２のうちタンク部材１０の上面部の上方部位に逆止弁１８を配置している。これにより、第２出口パイプ１４２の他端側は、逆止弁１８を介して蒸発器８の入口配管１４３に接続してある。この入口配管１４３は減圧装置７０の出口側と蒸発器８の入口側との間を結合する配管である。
【０１６６】
逆止弁１８は図２の第２逆止弁１８と同様のものであり、弁体１８ａに対して入口１８ｂから出口１８ｃの方向に冷媒圧力が作用するときは弁体１８ａが弁座部１８ｄから開離して開弁状態となる。図８は逆止弁１８の開弁状態を示す。逆に、弁体１８ａに対して出口１８ｃから入口１８ｂの方向に冷媒圧力が作用するときは弁体１８ａが弁座部１８ｄに圧着して閉弁状態となる。
【０１６７】
第２出口パイプ１４２には、第１出口パイプ１４１の気相冷媒吸入口１４１ｂの上方側と蓄冷熱交換器１１の下方側との間に板部材１４２ａを設け、この板部材１４２ａにより気相冷媒吸入口１４１ｂの周辺部の液冷媒液面に上方から冷媒流が衝突することを防止している。それにより、冷媒流衝突による冷媒液面の波立ちを防止するとともに、気液分離後の気相冷媒を圧縮機吸入側に確実に戻すことができる。
【０１６８】
なお、第２実施形態はアキュムレータ式の冷凍サイクルに関するものであって、アキュムレータタンクの役割を兼ねるタンク部材１０にて蒸発器出口冷媒の気液を分離して液冷媒を溜める。そして、第１出口パイプ１４１の気相冷媒吸入口１４１ｂから気相冷媒を吸入して圧縮機１の吸入側に送り込むことができる。
【０１６９】
従って、蒸発器出口冷媒の過熱度の調節を行わなくても圧縮機１の液冷媒圧縮を防止できるので、第２実施形態では減圧装置７０としてキャピラリチューブ、オリフィス等の固定絞り、あるいは高圧冷媒圧力に応動する可変絞り等を使用することができる。これらの減圧装置７０は、過熱度制御機構を持つ温度式膨張弁７に比して構成が簡素で、安価である。
【０１７０】
図９は第２実施形態による車両走行時の通常冷房・蓄冷モードであり、車両エンジン４により圧縮機１が駆動されることにより、図９の矢印で示す回路、すなわち、圧縮機１の吐出側→凝縮器６→減圧装置７０→入口配管１４３→蒸発器８→入口パイプ１２０→蓄冷熱交換器１１→第１出口パイプ１４１→圧縮機１の吸入側に至る回路にて冷媒が循環し、蒸発器８にて低圧冷媒が空調ケース２１内の送風空気から吸熱して蒸発することにより送風空気が冷却され車室内の冷房を行うことができる。
【０１７１】
また、蓄冷熱交換器１１において蓄冷材１１ａ’を低圧冷媒により冷却して凝固させることにより蓄冷材１１ａ’への蓄冷を行う。なお、通常冷房・蓄冷モードでは、電動ポンプ１５は第１実施形態と同様に停止しており、また、逆止弁１８は閉弁している。
【０１７２】
図１０は第２実施形態による停車時の放冷冷房モードであり、このときは電動ポンプ１５を作動させ、図１０の矢印で示す回路により冷媒を循環させる。すなわち、タンク部材１０下部の液冷媒タンク部１０ａ内の液冷媒を電動ポンプ１５にて吸入、吐出することにより、電動ポンプ１５→第２出口パイプ１４２→逆止弁１８（開弁状態）→入口配管１４３→蒸発器８→入口パイプ１２０→蓄冷熱交換器１１→液冷媒タンク部１０ａに至る回路にて冷媒が循環する。
【０１７３】
これにより、液冷媒タンク部１０ａの貯留液冷媒を蒸発器８に循環するとともに、蒸発器８で蒸発した気相冷媒を蓄冷熱交換器１１により冷却、液化させることにより、第１実施形態と同様に第２実施形態でも停車時の放冷冷房機能を良好に発揮できる。
【０１７４】
ところで、第２実施形態においても、液冷媒タンク部１０ａを一体形成したタンク部材１０内に、蓄冷熱交換器１１および電動ポンプ１５を一体化しているから、第１実施形態と同様に蓄冷ユニット９の車両搭載性を向上できる（前述の（１）の作用効果）。
【０１７５】
また、第２実施形態において、タンク部材１０内の上部に蓄冷熱交換器１１を配置し、蓄冷熱交換器１１の下方に電動ポンプ１５および液冷媒タンク部１０ａを配置すること、蒸発器８出口からの冷媒流入部をなす入口パイプ１２０をタンク部材１０の上部に配置すること等も第１実施形態と同様であり、そのため、第２実施形態でも第１実施形態の前述の（２）〜（５）の作用効果を同様に発揮できる。
【０１７６】
ところで、第２実施形態はアキュムレータ式の冷凍サイクルであるため、蒸発器８の出口側に蓄冷熱交換器１１を直列接続している。これは次の理由による。すなわち、アキュムレータ式の冷凍サイクルでは、減圧装置７０をキャピラリチューブ、オリフィス等の固定絞り、あるいは高圧冷媒圧力に応動する可変絞り等により構成することができ、膨張弁７を使用する必要がない。従って、蒸発器８の出口側に蓄冷熱交換器１１を直列接続しても、前述の蒸発器出口冷媒の過熱度調節の不具合が生じない。
【０１７７】
そして、蒸発器８の冷媒通路を流れる冷媒流れには必ず圧力損失が発生するので、蒸発器８の入口側に比して出口側の方が冷媒圧力（蒸発圧力）が低下する。ここで、アキュムレータ式の冷凍サイクルでは、アキュムレータ部、本実施形態ではタンク部材１０内部に冷媒の気液界面が形成され冷媒が飽和状態になっているので、蒸発器８内の冷媒が過熱状態にならない。従って、蒸発器８の出口側では冷媒圧力の低下に伴って冷媒温度（蒸発温度）が必ず入口側よりも低下する。
【０１７８】
この結果、アキュムレータ式の冷凍サイクルにおいて、蒸発器８の出口側に蓄冷熱交換器１１を直列接続することにより、蓄冷材１１ａ’をより低温の冷媒にて冷却でき、蓄冷材１１ａ’と冷媒との温度差を拡大して熱交換効率を向上でき、蓄冷材１１ａ’の凝固をより短時間で完了できる。
【０１７９】
（第１、第２実施形態の変形例）
なお、第２実施形態では、図８に示すように蓄冷ユニット９のタンク部材１０内にＵ状に曲げ形成した第１出口パイプ１４１を配置し、第１出口パイプ１４１の一端部をタンク部材１０の上面部から外部へ取り出すように構成しているが、図８に２点鎖線で図示するように第１出口パイプ１４１をタンク部材１０の底面部から外部へ取り出すように構成してもよい。
【０１８０】
また、第２実施形態において逆止弁１８は電動ポンプ１５の停止時、すなわち、通常冷房・蓄冷モード時に閉弁することにより、蒸発器８の入口配管１４３から低圧冷媒が第２出口パイプ１４２側へ逆流することを防止するものであるから、電動ポンプ１５自身の停止時の流通抵抗により低圧冷媒の上記逆流を実用上問題のないレベルに低下できるのであれば、逆止弁１８を廃止してもよい。
【０１８１】
また、第１実施形態では、タンク部材１０の下部の断面積をタンク部材１０の上部よりも小さくして液冷媒タンク部１０ａを形成している。また、第２実施形態では、タンク部材１０の下部の断面積をタンク部材１０の上部の断面積と同一にして液冷媒タンク部１０ａを形成している。
【０１８２】
しかし、車両搭載上の都合等により液冷媒タンク部１０ａの高さ寸法を縮小したい場合には、タンク部材１０の下部の断面積をタンク部材１０の上部よりも大きくして液冷媒タンク部１０ａをタンク部材１０の上部よりも水平方向に拡大する形状とし、これにより、液冷媒タンク部１０ａの必要容積を確保するようにしてもよい。
【０１８３】
また、第１、第２実施形態では、いずれも図２、図８に示すように、液冷媒タンク部１０ａの内部に電動ポンプ１５を配置しているが、液冷媒タンク部１０ａの液冷媒をタンク外部に取り出す出口パイプ１４、１４２のうちタンク外部の部位に電動ポンプ１５を配置しても良い。この場合、出口パイプ１４、１４２を液冷媒タンク部１０ａの下方側に取り出し、電動ポンプ１５を液冷媒タンク部１０ａの下方側に配置すれば、電動ポンプ１５の吸入側に液冷媒が充満した状態で電動ポンプ１５を始動できる。
【０１８４】
（第３実施形態）
第１実施形態では、図２に示すようにタンク部材１０の内部において蓄冷熱交換器１１の下方側に第１逆止弁１３を配置し、車両走行時の通常冷房・蓄冷モード時に第１逆止弁１３の入口１３ｂから蓄冷熱交換器１１の下方側の冷媒を吸入し、この吸入冷媒を蒸発器８の入口側に導入するようにしている。このため、液冷媒タンク部１０ａの貯留液冷媒の液面が前述したように第１逆止弁１３の設定高さよりも上昇しないようになっている。故に、第１実施形態では、停車時の放冷冷房モードに必要な液冷媒量を貯留するに必要な容積を持った液冷媒タンク部１０ａを蓄冷熱交換器１１の下方側に形成する必要が生じる。このことがタンク部材１０の小型化の大きな阻害要因となる。
【０１８５】
そこで、第３実施形態では、液冷媒タンク部１０ａの容積が同一であっても、第１実施形態に比較してタンク部材１０を小型化できるようにするものである。
【０１８６】
図１１は第３実施形態を示すものであり、図２（第１実施形態）と同等部分には同一符号を付して説明を省略し、以下第１実施形態との相違点について説明する。タンク部材１０の底面部の中心部に下方へ円筒状に突き出すポンプ収納部１０ｂを形成し、このポンプ収納部１０ｂ内に電動ポンプ１５を収納し、固定している。
【０１８７】
このポンプ収納部１０ｂの内周面と電動ポンプ１５の外周面との間には所定間隔の冷媒流路１０ｃを形成してポンプ収納部１０ｂ底部の液溜め部１０ｄまで液冷媒が流入するようになっている。そして、電動ポンプ１５の吸入口１５ａをポンプ底面部に配置して液溜め部１０ｄの液冷媒を吸入するようになっている。また、電動ポンプ１５の吐出口１５ｂはポンプ上面部に配置して出口パイプ１４の下端部に接続される。
【０１８８】
蓄冷熱交換器１１は、前述の図３（ａ）の円筒（スティック）タイプの蓄冷材容器１１ａを多数本上下方向に配置した構成になっているが、第３実施形態では、タンク部材１０内における蓄冷熱交換器１１の設置場所をタンク部材１０の底面部に近接した部位に引き下げている。具体的には、蓄冷熱交換器１１の下端部とタンク部材１０の底面部との間に、例えば、４ｍｍ程度の微小間隔ｈのみが設定されるように蓄冷熱交換器１１の設置場所を引き下げている。蓄冷熱交換器１１の下方にはこの微小間隔ｈにより液溜め空間１０ｅが構成される。
【０１８９】
そして、出口パイプ１４の接続口１４ａおよび第１逆止弁１３を、蓄冷熱交換器１１の上下方向の中間部位に配置している。この出口パイプ１４の接続口１４ａおよび第１逆止弁１３の周囲を蓄冷熱交換器１１の上方空間と仕切るための仕切り部材１１０を蓄冷熱交換器１１の中心部に設けている。
【０１９０】
この仕切り部材１１０は円板状の上面蓋部１１１と上面蓋部１１１の下側に位置する円筒部１１２とを有し、この円筒部１１２の内側に第１逆止弁１３を配置するとともに、出口パイプ１４は上面蓋部１１１を貫通して上下方向に延びるように配置されている。円筒部１１２の下端部は開口部１１３を形成しているので、第１逆止弁１３の入口１３ｂはこの開口部１１３により液溜め空間１０ｅのみに連通し、蓄冷熱交換器１１の上方空間とは連通しないようになっている。
【０１９１】
第３実施形態によると、第１逆止弁１３の入口１３ｂを蓄冷熱交換器１１の上下方向の中間部位に配置しているから、車両走行時の通常冷房・蓄冷モード時にタンク部材１０内に貯留される液冷媒の液面Ｌが第１逆止弁１３の入口１３ｂ付近の高さまで上昇することができる。これにより、タンク部材１０内部において蓄冷熱交換器１１の上下方向の中間部位まで液冷媒の貯留領域となる。
【０１９２】
従って、第３実施形態では、タンク部材１０内底面部付近の液溜め空間１０ｅのみならず、蓄冷熱交換器１１の多数本の蓄冷材容器１１ａ相互間の空間をも利用して液冷媒タンク部１０ａを構成できる。この結果、液冷媒タンク部１０ａの容積が同一であっても、第３実施形態のタンク部材１０の高さ寸法を図２の第１実施形態に比較して大幅に縮小でき、タンク部材１０を小型化できる。これにより、蓄冷ユニット９の車両搭載性を向上できる。
【０１９３】
ところで、第３実施形態によると、蓄冷熱交換器１１の多数本の蓄冷材容器１１ａ相互間の空間をも利用して液冷媒タンク部１０ａを構成するので、蓄冷材容器１１ａの下側部分が液冷媒中に浸漬することになり、このことから車両走行時の蓄冷能力および停車時の放冷能力の低下が懸念されるが、実際は以下の工夫により上記能力低下をほとんど問題とならないレベルに抑制できる。
【０１９４】
先ず、蓄冷能力について述べると、出口パイプ１４の接続口１４ａおよび第１逆止弁１３の周囲を仕切り部材１１０により仕切って、第１逆止弁１３の入口１３ｂを仕切り部材１１０下端の開口部１１３により液溜め空間１０ｅのみに連通し、入口１３ｂが蓄冷熱交換器１１の上方空間とは連通しないようにしている。
【０１９５】
このため、車両走行時の蓄冷時には、膨張弁７の弁部７ａで減圧された低温低圧の冷媒が入口パイプ１２からタンク部材１０内に流入した後、この流入冷媒が直接第１逆止弁１３の入口１３ｂに向かうことが仕切り部材１１０により阻止される。
【０１９６】
これにより、この流入冷媒はタンク部材１０内において蓄冷熱交換器１１の上面部から多数の蓄冷材容器１１ａ相互間の隙間部を下方へと流れ、タンク部材１０内底面部付近の液溜め空間１０ｅに到達し、しかる後、冷媒は開口部１１３を通過して第１逆止弁１３の入口１３ｂに吸入される。
【０１９７】
このように、蓄冷時にはタンク部材１０内への流入冷媒が必ず蓄冷材容器１１ａ相互間の隙間部を下方へと流れて蓄冷材容器１１ａの下側部分の表面に接している液冷媒を流動させ、撹拌する。これにより、蓄冷材容器１１ａの下側部分が液冷媒域に浸漬していても、蓄冷材容器１１ａの下側部分の表面における熱伝達率の低下を、実際上ほとんど問題とならないレベルに抑制でき、必要な蓄冷能力を確保できる。
【０１９８】
次に、放冷能力について説明すると、停車時の放冷時には電動ポンプ１５を作動させて、液溜め部１０ｄの貯留液冷媒を吸入して蒸発器８に導入し、蒸発器８で蒸発した気相冷媒を蓄冷熱交換器１１に還流し、この蓄冷熱交換器１１にて気相冷媒を冷却して凝縮させる。ここで、蓄冷熱交換器１１における気相冷媒の凝縮量は、蓄冷熱交換器１１での伝熱面積等の熱交換器仕様と、蓄冷材１１ａ’の融点等の物性により求めることができる。
【０１９９】
そして、この気相冷媒の凝縮量よりも電動ポンプ１５による液冷媒循環量が多くなるように電動ポンプ１５の吐出能力を設定することにより、放冷時に液冷媒の液面Ｌを蓄冷熱交換器１１の下端部よりも下方へ下げることができる。これにより、蒸発器８出口から還流する気相冷媒を蓄冷熱交換器１１の蓄冷材容器１１ａの表面全体で効率よく冷却して凝縮させることができるので、放冷能力の低下を防止できる。
【０２００】
（第４実施形態）
上記第３実施形態では、蓄冷熱交換器１１の中心部にて、蓄冷熱交換器１１の上下方向の中間部位に出口パイプ１４の接続口１４ａおよび第１逆止弁１３を配置しているが、第４実施形態では、図１２に示すように、出口パイプ１４の接続口１４ａおよび第１逆止弁１３を蓄冷熱交換器１１の下方側の液溜め空間１０ｅに配置している。
【０２０１】
一方、第１逆止弁１３の入口１３ｂに入口配管１３ｆを接続し、この入口配管１３ｆの先端側を円筒状の仕切り部材１１０内に挿入して、入口配管１３ｆの先端開口１３ｇを円筒状の仕切り部材１１０内において蓄冷熱交換器１１の上下方向の中間部位に配置している。
【０２０２】
これにより、第４実施形態では第１逆止弁１３を蓄冷熱交換器１１の下方側の液溜め空間１０ｅに配置していても、液冷媒の液面Ｌを入口配管１３ｆの先端開口１３ｇの位置、すなわち、蓄冷熱交換器１１の上下方向の中間部位まで上昇させることができる。従って、第３実施形態と同様に、蓄冷熱交換器１１の多数本の蓄冷材容器１１ａ相互間の空間をも利用して液冷媒タンク部１０ａを構成できる。この結果、第４実施形態においても、蓄冷熱交換器１１の下方側の液溜め空間１０ｅの容積を図２の第１実施形態に比較して大幅に縮小でき、タンク部材１０を小型化できる。
【０２０３】
また、第３実施形態に比較すると、第４実施形態では円筒状の仕切り部材１１０の容積を大幅に縮小できるので、その分だけ、蓄冷熱交換器１１の容積を増大して蓄冷材充填量の増加を図ることができる。
【０２０４】
なお、第３実施形態および第４実施形態では、蓄冷熱交換器１１の蓄冷材容器１１ａを図３（ａ）に示す円筒状タイプのもので構成する例について説明したが、蓄冷熱交換器１１の蓄冷材容器１１ａを図３（ｂ）に示すボールタイプ、あるいは図３（ｃ）に示すカプセルタイプのもので構成してもよい。
【０２０５】
（第５実施形態）
図１３は第５実施形態であり、蓄冷熱交換器１１の蓄冷材容器１１ａを図３（ｂ）に示すボールタイプのもので構成し、このボールタイプの蓄冷材容器１１ａを第１逆止弁１３、出口パイプ１４および電動ポンプ１５の周囲空間に直接、密に配置している。すなわち、多数のボールタイプの蓄冷材容器１１ａを互の球面が密着するように上記周囲空間に敷き詰めてある。従って、多数のボールタイプの蓄冷材容器１１ａ相互の球面同士の間には微小な空隙からなる冷媒流路が迷路状に形成される。
【０２０６】
蓄冷熱交換器１１の下端部とケース１０の底面部との間に微小間隔ｈを設定して、液溜め空間１０ｅを形成している。電動ポンプ１５はこの液溜め空間１０ｅの液冷媒を吸入するようになっている。
【０２０７】
第５実施形態では、第３、第４実施形態における仕切り部材１１０を廃止している。しかし、入口パイプ１２の開口端１２ａを第１逆止弁１３の入口１３ｂと反対方向、図１３の例では右方向に向けているので、入口パイプ１２の開口端１２ａから低圧冷媒は第１逆止弁１３の入口１３ｂと反対方向に向かって流出する。しかも、第１逆止弁１３の周囲には多数のボールタイプの蓄冷材容器１１ａを密に敷き詰め、多数の蓄冷材容器１１ａ相互の球面同士の間に微小な空隙からなる冷媒流路を迷路状に形成しているので、車両走行時の蓄冷時に、入口パイプ１２の開口端１２ａから流出した低圧冷媒は、この蓄冷材容器１１ａ相互の迷路状冷媒流路を通過した後に、第１逆止弁１３の入口１３ｂに向かって流れる。
【０２０８】
以上のことから、仕切り部材１１０を廃止しても、入口パイプ１２から流出した低圧冷媒が直ちに第１逆止弁１３の入口１３ｂに向かって流れることはなく、第１逆止弁１３の入口１３ｂから離れた部位から低圧冷媒が蓄冷材容器１１ａ相互の迷路状冷媒流路を通過するので、蓄冷熱交換器１１のうちかなり広範囲の蓄冷材容器１１ａ相互間の冷媒流路を低圧冷媒が通過する。この結果、蓄冷材容器１１ａの下側部分が液冷媒域に浸漬する構成であって、かつ、仕切り部材１１０を廃止しても、第３、第４実施形態に対する蓄冷能力の低下を僅少量に抑制できる。
【０２０９】
なお、放冷時には第３、第４実施形態と同様に気相冷媒の凝縮量よりも電動ポンプ１５による液冷媒循環量が多くなるように電動ポンプ１５の吐出能力を設定することにより、第３、第４実施形態と同等の放冷能力を確保できる。
【０２１０】
第５実施形態によると、第１逆止弁１３を蓄冷熱交換器１１の内部に配置するとともに、電動ポンプ１５も、その大部分を蓄冷熱交換器１１の内部に配置する構成であるから、第３、第４実施形態よりも一層タンク部材１０を小型化できる。特に、タンク部材１０の全高さ寸法の短縮効果が大である。
【０２１１】
また、仕切り部材１１０を廃止して第１逆止弁１３の周囲に多数のボールタイプの蓄冷材容器１１ａを直接、密に敷き詰めているから、仕切り部材１１０の仕切り空間による蓄冷材充填容積の減少が発生せず、蓄冷材充填量を増加することができる。
【０２１２】
（第６実施形態）
第６実施形態は蓄冷ユニット９の体格の大部分を占める蓄冷熱交換器１１の小型化に関するものである。蓄冷熱交換器１１は、所定の蓄冷および放冷能力を発揮するために、この蓄冷、放冷能力に対応した大きな伝熱面積が必要となる。そして、この伝熱面積を確保しつつ、蓄冷材充填量を増加して蓄冷容量を増大しようとすると、蓄冷熱交換器１１がどうしても大型化し、且つ、熱交換器重量も増えて、蓄冷ユニット９の車両搭載性が悪化する。
【０２１３】
そこで、第６実施形態では蓄冷熱交換器１１の伝熱構成の工夫によって蓄冷熱交換器１１の小型化を図るものである。図１４、図１５は第６実施形態による蓄冷熱交換器１１の具体例を示し、図１６は第６実施形態による蓄冷熱交換器１１を蓄冷ユニット９内に組み込んだ例を示す。図１６は、図１に示す膨張弁サイクル、すなわち、減圧手段として膨張弁７を用いて蒸発器出口冷媒の過熱度制御を行う冷凍サイクルＲに適用した場合の蓄冷ユニット９を示している。
【０２１４】
第６実施形態による蓄冷熱交換器１１は一般にシェルアンドチューブタイプと称される熱交換器構成を基本にしている。すなわち、蓄冷熱交換器１１は円筒状のタンク部材であるシェル１１ｄと、このシェル１１ｄに固定され、冷媒流路を構成するチューブ１１ｅと、このチューブ１１ｅに熱的に一体に結合され、チューブ１１ｅの拡大伝熱面を構成するフィン１１ｆとを有している。
【０２１５】
シェル１１ｄは円筒状本体部１１ｇの上端部および下端部を上蓋部１１ｈおよび下蓋部１１ｉにより密封した構成になっている。シェル１１ｄの外径は図１６に示すように蓄冷ユニット９のケース部材１０の内周面に嵌合するように設定され、シェル１１ｄはケース部材１０の内周面に固定される。
【０２１６】
チューブ１１ｅは本例では円管状のものであり、フィン１１ｆは円形の平板形状からなるプレートフィンである。フィン１１ｆにはチューブ挿入用のバーリング穴１１ｊが開けてある。平板状のフィン１１ｆは所定のフィンピッチＰｆにて多数枚積層され、バーリング穴１１ｊに円管状のチューブ１１ｅを挿入した後に、円管状のチューブ１１ｅを拡管することにより、フィン１１ｆとチューブ１１ｅとを機械的に一体に固定する。この機械的な固定と同時に、フィン１１ｆとチューブ１１ｅとを熱的にも一体に結合するようになっている。
【０２１７】
そして、フィン１１ｆとチューブ１１ｅの固定後に、チューブ１１ｅがシェル１１ｄに対して上下方向に延びる縦置きとし、多数枚のフィン１１ｆとチューブ１１ｅとの結合体をシェル１１ｄ内部に収容し、かつ、チューブ１１ｅの上端部および下端部がシェル１１ｄの上側および下側へそれぞれ突き出すようにシェル１１ｄに対して組み付ける。
【０２１８】
この組み付けにおいて、チューブ１１ｅの上端部付近および下端部付近の部位はシェル１１ｄの上蓋部１１ｈおよび下蓋部１１ｉにそれぞれろう付け等の接合手段によりシールして固定される。
【０２１９】
チューブ１１ｅとフィン１１ｆとは熱伝導率のよい金属例えば、アルミニュウムにて成形される。また、シェル１１ｄの各部１１ｇ、１１ｈ、１１ｉもアルミニュウム等の金属で成形される。
【０２２０】
密封ケース構造をなすシェル１１ｄの一部、例えば、上蓋部１１ｈに蓄冷材注入口１１ｋを設け、この注入口１１ｋからシェル１１ｄの内部に蓄冷材１１ａ’を注入するようになっている。シェル１１ｄの内部において蓄冷材１１ａ’は平板状のフィン１１ｆ相互間の間隙（フィンピッチＰｆによる間隙）に充填される。蓄冷材１１ａ’の注入終了後に、注入口１１ｋはプラグ１１ｍにより密封される。
【０２２１】
ここで、蓄冷材１１ａ’は、車両用空調装置の蓄冷という用途であるため、４℃〜８℃程度の融点を有し、過冷却の発生しない物性を有するものが好ましい。このような物性を満足するものとして具体的にはパラフィン（ｎ−テトラデカン）が好適である。
【０２２２】
ところで、蓄冷材１１ａ’として用いるパラフィンは、金属に比べて熱伝導率がかなり小さいので、蓄冷能力および放冷能力を高めるためにはパラフィンの層を薄くして、伝熱面積を大きくすることが望ましい。このために、蓄冷熱交換器１１をシェルアンドチューブタイプの熱交換器構成として、フィン１１ｆ相互間の微小間隙部（フィンピッチＰｆによる間隙部）にパラフィンを薄膜状に充填するようにしている。
【０２２３】
ここで、フィンピッチＰｆは後述するように蓄冷熱交換器１１の伝熱性能の確保と小型化のために０．５〜２ｍｍ程度の範囲が好ましく、より具体的には１．５ｍｍ付近の値に設定する。
【０２２４】
また、蓄冷材１１ａ’は、蓄冷モード・放冷モードの変化に伴って相変化し、それに伴って密度が変化し、体積が変化する。この蓄冷材１１ａ’の体積変化によって平板状のフィン１１ｆには応力が発生し、蓄冷熱交換器１１の金属疲労の原因となる。
【０２２５】
そこで、積層された多数枚の平板状のフィン１１ｆを上下方向に貫通する貫通穴１１ｎを図１４に示すように各フィン１１ｆに設けている。これにより、放冷モード時に蓄冷材１１ａ’が固相状態から液相状態に相変化するときに蓄冷材１１ａ’の体積が増加しても、フィン間の液相の蓄冷材１１ａ’を貫通穴１１ｎを通してフィン外部へスムースに移動させることができる。
【０２２６】
なお、図１４では、貫通穴１１ｎを円形の平板形状からなるプレートフィン１１ｆの中心部に１箇所のみ設ける例を図示しているが、実際には、液相の蓄冷材１１ａ’のスムースな移動のために貫通穴１１ｎを所定間隔にて複数箇所設けることが好ましい。
【０２２７】
また、シェル１１ｄの円筒状本体部１１ｇの内周面と、平板状フィン１１ｆの外周端との間には、所定間隔Ｂ（例えば２ｍｍ程度）を有する断熱用の隙間部１１ｐを設けている。この隙間部１１ｐは、蓄冷ユニット９を車室外の高温環境（例えば、エンジンルーム等）に設置しても蓄冷材１１ａ’の蓄冷熱の断熱作用を確保できるようにするためのものである。
【０２２８】
チューブ１１ｅとして、前述のように本例では円管状のもの（丸チューブ）を用いており、チューブ設置本数を増やして冷媒側伝熱面積を確保するためには円管状チューブ１１ｅの内径は４ｍｍ程度以下が好ましい。なお、チューブ１１ｅとして偏平チューブあるいは偏平多穴チューブを採用することも可能である。偏平チューブの場合は冷媒側伝熱面積を確保するために内径１ｍｍ程度の等価直径を持つものが好ましい。
【０２２９】
次に、第６実施形態による作用効果を説明する。なお、第６実施形態による蓄冷熱交換器１１を持つ蓄冷ユニット９全体の作動は第１実施形態（図２）と同じであるので、説明を省略する。
【０２３０】
第６実施形態による蓄冷熱交換器１１では、熱交換器基本構成をシェルアンドチューブタイプの熱交換器構成として、平板状のフィン１１ｆ相互間の微小間隙部（フィンピッチＰｆによる間隙部）にパラフィンを薄膜状に充填していることが第１の特徴であり、この第１の特徴は以下の検討に基づいて案出されてものである。
【０２３１】
本発明者は、先ず、蓄冷熱交換器１１が車両停車時における放冷冷房のために用いられるという前提の下に、蓄冷材１１ａ’に潜熱蓄冷する際の伝熱隔壁の形態として、▲１▼１次元的な面構成、▲２▼２次元的な面構成、▲３▼３次元的な面構成のいずれが小型化のために最も有利であるか比較検討することにした。
【０２３２】
そこで、上記▲１▼〜▲３▼の伝熱隔壁の代表例として、図１７に示す▲１▼平面・積層タイプ（平行平板タイプ）、▲２▼円筒タイプ（図３（ａ）のタイプ）、▲３▼ボールタイプ（図３（ｂ）のタイプ）を取り上げ、この３種類の伝熱隔壁▲１▼〜▲３▼について、同一蓄冷材重量（６００ｇ）の下、同一の蓄冷、放冷能力が得られる形状別の伝熱面積をコンピュータシュミレーションにより算出し、比較検討してみた。図１７の伝熱面積はこのコンピュータシュミレーションによる算出結果を示す。
【０２３３】
なお、図１７の算出例では、蓄冷材として、パラフィン（融点：５．９℃のｎ−テトラデカン）を使用しており、また、各形状の伝熱隔壁は板厚０．３ｍｍのアルミニュウム合金材を使用している。
【０２３４】
図１７において、▲１▼平面・積層タイプ（平行平板タイプ）の伝熱隔壁は、第６実施形態によるシェルアンドチューブタイプの蓄冷熱交換器１１における平行平板タイプのプレートフィンｆ１１により構成できる。従って、図１７の▲１▼におけるｄ寸法は、図１４のフィンピッチＰｆからプレートフィンｆ１１の板厚分（０．３ｍｍ）を減算した値である。
【０２３５】
図１７に示す各形状の伝熱隔壁の伝熱面積の比較から明らかなように、同一の蓄冷、放冷能力を発揮するに必要な伝熱面積を、▲１▼平面・積層タイプ（平行平板タイプ）の伝熱隔壁により最も小さくできることが分かる。すなわち、平面・積層タイプの伝熱隔壁が熱交換器小型化のために最も有利であることが分かる。
【０２３６】
これは次の理由による。すなわち、相変化により蓄冷を行う場合に蓄冷材の厚みを小さくすることが有利であるが、上記３種類の伝熱隔壁の伝熱面積を同一とした場合に、円筒タイプ▲２▼であると蓄冷材の厚み（図１７の内径ｄに相当）が平面・積層タイプ▲１▼の２倍に増加し、また、ボールタイプ▲３▼であると蓄冷材の厚み（図１７の内径ｄに相当）が平面・積層タイプ▲１▼の３倍に増加するので、伝熱性能が同一とならず、平面・積層タイプ▲１▼→円筒タイプ▲２▼→ボールタイプ▲３▼の順に伝熱性能が低下してしまうからである。
【０２３７】
図１７の検討結果から、第６実施形態のように平面・積層タイプ▲１▼の伝熱隔壁、すなわち、平板状のフィン１１ｆを持つシェルアンドチューブタイプの蓄冷熱交換器１１を構成することにより、円筒タイプ▲２▼やボールタイプ▲３▼の伝熱隔壁を持つ蓄冷熱交換器に比較して、熱交換器体格（図１７の占有体積）を１０〜２５％程度小型化でき、車両搭載性の向上にとって非常に有利である。図１７の占有体積の単位［Ｌ］はリットルを示す。
【０２３８】
なお、図１７において、充填率は、蓄冷熱交換器の占有体積に対する伝熱隔壁と蓄冷材の合計体積の比率である。円筒タイプ▲２▼やボールタイプ▲３▼の伝熱隔壁の場合は、その隔壁形状自体により充填率が必然的に決まるが、第６実施形態による平面・積層タイプ▲１▼の伝熱隔壁の場合は、その隔壁形状自体により充填率が必然的に決まらないので、冷媒チューブ１１ｅの存在を考慮して充填率＝０．９の値を適用している。
【０２３９】
ところで、図１７の比較検討では、上述のように、各形状の伝熱隔壁の板厚を同一条件、具体的には板厚ｔ＝０．３ｍｍを適用しているが、第６実施形態によるシェルアンドチューブタイプの熱交換器構成であると、冷媒チューブ１１ｅのみに冷媒圧力が作用し、伝熱隔壁（拡大伝熱面）をなす平板状のフィン１１ｆには冷媒圧力が作用しない。このため、平板状のフィン１１ｆには、冷媒圧力に対する耐圧強度確保のための板厚が要求されない。
【０２４０】
従って、第６実施形態では、蓄冷熱交換器１１を構成するに当たり、平板状のフィン１１ｆを構成する金属として熱伝導率の良いアルミニュウム合金を用いることにより、平板状のフィン１１ｆの板厚について冷媒チューブ１１ｅよりも一層を薄肉化することができる。具体的には、冷媒チューブ１１ｅの板厚＝０．３ｍｍとし、一方、平板状のフィン１１ｆの板厚は０．１ｍｍ程度まで薄肉化することができる。そして、平板状のフィン１１ｆの板厚を０．１ｍｍ程度まで薄肉化してもフィン効率の低下は無視できるほど小さい。
【０２４１】
なお、比較例▲２▼、▲３▼の伝熱隔壁の場合はいずれも蓄冷材容器を構成し、その外表面側に冷媒通路が形成され、伝熱隔壁の外表面側に冷媒圧力が直接作用するので、耐圧強度確保の観点から薄肉化がしにくい。
【０２４２】
以上のように、第６実施形態のシェルアンドチューブタイプの熱交換器構成であると、伝熱隔壁をなす平板状フィン１１ｆの板厚を冷媒通路をなすチューブ１１ｅの板厚よりも小さい値に独立に設定できるので、熱交換器占有体積を図１７の検討結果よりも実際には一層小さくでき、熱交換器体格を効果的に小型化でき、且つ、軽量化も達成できる。
【０２４３】
次に、平板状のフィン１１ｆのフィンピッチＰｆについて言及すると、フィンピッチＰｆは次の理由から０．５ｍｍ〜２ｍｍの範囲が好適である。すなわち、フィンピッチＰｆを２ｍｍよりも大きくすると、前述した蓄冷材１１ａ’の厚さ拡大による伝熱性能の低下、ひいては、蓄冷、放冷能力の低下が顕著となり、この能力低下を補うためには伝熱面積の拡大、ひいては熱交換器体格の増大を生じるので、フィンピッチＰｆは２ｍｍ以内とすることが好ましい。
【０２４４】
また、逆に、フィンピッチＰｆを小さくすると、伝熱性能としては十分であっても、蓄冷材単位体積当たりのフィン配置数量が必然的に増加してしまうので、熱交換器体格の小型化、軽量化のために不利となる。このため、フィンピッチＰｆは、実際上は０．５ｍｍ以上とすることが好ましい。
【０２４５】
ところで、第６実施形態によると、蓄冷熱交換器１１においてチューブ１１ｅが上下方向に縦配置され、冷媒がチューブ１１ｅ内を上方から下方へと流れるから、放冷時にチューブ１１ｅ内で冷却され凝縮した液冷媒は重力の影響により下方の液冷媒タンク部１０ａへ速やかに落下する。
【０２４６】
これにより、チューブ１１ｅ内面の凝縮液膜を常に薄く保つことができるので、放冷時の凝縮液膜による伝熱性能の低下を抑制でき、放冷性能を有効に発揮できる。
【０２４７】
また、第６実施形態では積層された多数枚の平板状フィン１１ｆを上下方向に貫通する貫通穴１１ｎ（図１４）を各フィン１１ｆに設けて、この貫通穴１１ｎを通して液相の蓄冷材１１ａ’が移動しやすくしている。このため、蓄冷時に蓄冷材１１ａ’が液相状態から固相状態に相変化するに伴って蓄冷材体積が減少する際は、貫通穴１１ｎを通して液相の蓄冷材１１ａ’をフィン外部からフィン間にスムースに補給できる。従って、フィン間にて蓄冷材１１ａ’を効率よく冷却して短時間で蓄冷を完了できる。
【０２４８】
一方、放冷時には蓄冷材１１ａ’が固相状態から液相状態に相変化するに伴って蓄冷材体積が増加するが、その際に、貫通穴１１ｎを通して液相の蓄冷材１１ａ’をスムースにフィン間からフィン外部へ押し出すことができる。このため、蓄冷材１１ａ’の相変化（体積変化）に伴う過大な応力がフィン１１ｆに発生することを回避できる。これにより、フィン１１ｆとチューブ１１ｅとの接合部の金属疲労を防止して、この接合部の耐久性を向上できる。
【０２４９】
また、第６実施形態では、シェル１１ｄの円筒状本体部１１ｇの内周面と、平板状フィン１１ｆの外周端との間には断熱用の隙間部１１ｐを設けて、蓄冷材１１ａ’の蓄冷熱の断熱作用を効果的に発揮できる。
【０２５０】
この断熱作用について詳述すると、シェル１１ｄの円筒状本体部１１ｇは図１６に示すように蓄冷ユニット９のケース部材１０の内壁面に直接嵌合しているので、ケース部材１０外部の高温雰囲気の熱がケース部材１０および円筒状本体部１１ｇの壁面を通して円筒状本体部１１ｇ内側に侵入して、隙間部１１ｐの温度が上昇する。
【０２５１】
これにより、隙間部１１ｐに位置する蓄冷材１１ａ’の温度が融点以上の温度になり、蓄冷材１１ａ’は液相状態を維持する。ここで、パラフィン、水等の蓄冷材１１ａ’の熱伝導率λは、固相状態よりも液相状態の方が大幅に小さくなる。例えば、パラフィンの場合、固相時の熱伝導率λ＝０．２８Ｗ／ｍＫであり、これに対し、液相時の熱伝導率λ＝０．１４Ｗ／ｍＫであり、固相時の熱伝導率λの１／２に減少する。
【０２５２】
従って、隙間部１１ｐに位置する蓄冷材１１ａ’が常にほぼ液相状態として存在することにより、蓄冷材１１ａ’が自身の熱伝導率の低さから断熱作用を効果的に発揮できる。このため、シェル１１ｄの円筒状本体部１１ｇとフィン１１ｆ部分との間に大きな温度差が発生しても、シェル１１ｄ側からの侵入熱量を効果的に低減できる。
【０２５３】
そのため、蓄冷ユニット９が蓄冷材１１ａ’の融点よりも十分温度が高い高温雰囲気に配置されても、蓄冷ユニット９外部への冷熱損失を効果的に抑制できる。これによって、蓄冷ユニット９のケース部材１０に別途設ける断熱材を不要にしたり、断熱材を別途設ける場合でも断熱材使用量を大幅に低減できる。
【０２５４】
以上の説明から理解されるように、第６実施形態によると、車両エンジン停止時の放冷冷房の実現に必要な主要構成部品を液溜めのための共通のケース部材１０内にすべて収納した一体化ユニットからなる蓄冷ユニット９において、その体格の大部分を占める蓄冷熱交換器１１を効果的に小型化でき、蓄冷ユニット９の車両搭載性を向上できる。
【０２５５】
（第７実施形態）
なお、第６実施形態は図１６に示すように、減圧手段として膨張弁７を用いて蒸発器出口冷媒の過熱度制御を行う膨張弁サイクルに適用した場合の蓄冷ユニット９に関するものであるが、第６実施形態による蓄冷熱交換器構成は図７（第２実施形態）に示すアキュムレータサイクルにも同様に適用できる。
【０２５６】
図１８は第７実施形態を示すもので、図７に示すアキュムレータサイクルに第６実施形態の蓄冷熱交換器構成を適用したものである。図１８に示す第７実施形態の蓄冷ユニット９は、図８に示す第２実施形態の蓄冷ユニット９において、蓄冷熱交換器構成を第６実施形態の蓄冷熱交換器構成に置換したものに相当する。従って、図１８において図８および図１６と同等部分に同一符号を付して、第７実施形態の具体的説明は省略する。
【０２５７】
（第８実施形態）
第６実施形態による蓄冷熱交換器構成においては、図１４、１５に示すように１枚の円形平板状のフィン１１ｆに多数本のチューブ１１ｅを挿入する挿入穴（図１４の例ではバーリング穴）１１ｊを設け、この各挿入穴１１ｊにチューブ１１ｅを挿入し、この各挿入穴１１ｊ部分にて多数本のチューブ１１ｅを１枚の円形平板状のフィン１１ｆに一体に接合しているが、第８実施形態では図１９、図２０に示すように複数本の各チューブ１１ｅごとにそれぞれ分割した円形平板状のフィン１１ｆを一体に接合している。
【０２５８】
第６実施形態のように、多数本のチューブ１１ｅの挿入穴１１ｊを設けた円形平板状のフィン１１ｆを多数枚積層し、この多数枚の積層フィン群の各挿入穴１１ｊにチューブ１１ｅを挿入し接合する組付構造では、挿入穴１１ｊの内径とチューブ１１ｅの外形の寸法バラツキ、挿入穴１１ｊの穴ピッチのバラツキ等の影響を受けて、組付作業が困難になることがある。
【０２５９】
これに対し、第８実施形態では各チューブ１１ｅごとにそれぞれ対応して円形平板状のフィン１１ｆを分割成形し、各チューブ１１ｅごとにフィン１１ｆを多数枚積層し、この多数枚の積層フィン群の挿入穴１１ｊにチューブ１１ｅを挿入し接合する。すなわち、各チューブ１１ｅ単位でチューブ１１ｅとフィン１１ｆの組付を行う。
【０２６０】
その後に、各チューブ１１ｅ単位の組付体を、各チューブ１１ｅが上下方向に向くように縦配置として集合し、この組付体のうちフィン１１ｆ結合部分をシェル１１ｄ内に収納するとともに、各チューブ１１ｅの上端部付近及び下端部付近をシェル１１ｄの上蓋部１１ｈ（図１４参照）、下蓋部１１ｉ（図１４参照）にシール固定する。
【０２６１】
第８実施形態によると、各チューブ１１ｅ単位でチューブ１１ｅとフィン１１ｆとを独立に組付を行うことができるから、上述のごとき寸法バラツキがあってもチューブ１１ｅとフィン１１ｆとの組付作業を容易に行うことができる。
【０２６２】
なお、チューブ１１ｅとフィン１１ｆとの接合は、第６実施形態と同様にチューブ拡管、ろう付け等の手段により行えばよい。
【０２６３】
（第９実施形態）
第８実施形態では、各チューブ１１ｅごとに分割成形した円形平板状のフィン１１ｆを多数枚積層し、この多数枚の積層フィン群の挿入穴１１ｊにチューブ１１ｅを挿入し接合しているが、第９実施形態では、図２１に示すように平板状のフィン１１ｆを円管状チューブ１１ｅの外周面上に鍛造加工により一体成形している。
【０２６４】
第９実施形態による平板状のフィン１１ｆは、チューブ長手方向と垂直な面から微小角度傾斜した螺旋状の形態で円管状チューブ１１ｅの外周面上に一体成形する。このため、円管状チューブ１１ｅの外周面上に螺旋状に連続する平板状のフィン１１ｆを効率よく一体成形できる。
【０２６５】
なお、第９実施形態によると平板状のフィン１１ｆは螺旋状に連続する形態となるため、上記第６〜第８実施形態のように、平板状のフィン１１ｆを平行平板配置するものとフィン配置形態が相違することになるが、螺旋状に連続する平板状のフィン１１ｆの螺旋ピッチＰｆ’を前述のフィンピッチＰｆと同様な範囲（０．５〜２．０ｍｍ）に設定することにより、上記第６〜第８実施形態と同様に蓄冷熱交換器１１を小型化できる。
【０２６６】
なお、第８、第９実施形態による蓄冷熱交換器構成を、図１６に示す膨張弁サイクル用の蓄冷ユニット９、および図１８に示すアキュムレータサイクル用の蓄冷ユニット９のいずれにも同様に適用できることはもちろんである。
【０２６７】
（他の実施形態）
なお、上記の各実施形態では、停車時に車両エンジン４を停止する制御を行う車両に搭載される車両用空調装置について説明したが、例えば、車両走行用の動力源として、車両エンジン４と電動モータの両方を備えるハイブリッド車に本発明を適用してもよい。ハイブリッド車では、車両走行時にも走行条件に応じて（例えば減速時、低負荷走行時等に）車両エンジン４を停止する場合もあるので、この車両走行時における車両エンジン４の停止時にも上記各実施形態の放冷モードを実施すればよい。
【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の回路図である。
【図２】図１の蓄冷ユニットの具体的構成を例示する断面図である。
【図３】図２の蓄冷材容器を例示する斜視図である。
【図４】第１実施形態による空調室内ユニット部の概略断面図である。
【図５】第１実施形態による通常冷房・蓄冷モード時の作動説明図である。
【図６】第１実施形態による放冷冷房モード時の作動説明図である。
【図７】第２実施形態を示す冷凍サイクルの回路図である。
【図８】図７の蓄冷ユニットの具体的構成を例示する断面図である。
【図９】第２実施形態による通常冷房・蓄冷モード時の作動説明図である。
【図１０】第２実施形態による放冷冷房モード時の作動説明図である。
【図１１】第３実施形態による蓄冷ユニットの具体的構成を例示する断面図である。
【図１２】第４実施形態による蓄冷ユニットの具体的構成を例示する断面図である。
【図１３】第５実施形態による蓄冷ユニットの具体的構成を例示する断面図である。
【図１４】第６実施形態による蓄冷熱交換器の具体的構成を例示する断面図である。
【図１５】第６実施形態による蓄冷熱交換器の具体的構成を例示する概略斜視図である。
【図１６】第６実施形態による蓄冷ユニットの具体的構成を例示する断面図である。
【図１７】第６実施形態による蓄冷熱交換器と比較例との伝熱隔壁仕様の比較を例示する図表である。
【図１８】第７実施形態による蓄冷ユニットの具体的構成を例示する断面図である。
【図１９】第８実施形態による蓄冷熱交換器の具体的構成を例示する概略斜視図である。
【図２０】第８実施形態による蓄冷熱交換器の要部断面図である。
【図２１】第９実施形態による蓄冷熱交換器の要部断面図である。
【図２２】従来装置の冷凍サイクルの回路図である。
【符号の説明】
１…圧縮機、４…車両エンジン、６…凝縮器（高圧側熱交換器）、
７…膨張弁（減圧手段）、７０…固定絞り等の減圧装置（減圧手段）、
８…蒸発器、９…蓄冷ユニット、１０…タンク部材、１０ａ…液冷媒タンク部、１１…蓄冷熱交換器、１１ａ…蓄冷材容器、１５…電動ポンプ。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a regenerative air conditioner for a vehicle that is applied to a vehicle that temporarily stops a vehicle engine that is a driving source of a compressor when the vehicle stops.
[0002]
[Prior art]
In recent years, vehicles (eco-run vehicles such as hybrid vehicles) that automatically stop the vehicle engine when the vehicle is stopped such as at a traffic light have been put into practical use for the purpose of environmental protection and improved fuel efficiency of the vehicle engine. Vehicles that stop the vehicle engine tend to increase.
[0003]
By the way, in the vehicle air conditioner, since the compressor of the refrigeration cycle is driven by the vehicle engine, the eco-run vehicle is stopped at a signal or the like, and the compressor is stopped every time the vehicle engine is stopped. As a result, the temperature of the cooling evaporator rises, and the temperature of the air blown into the passenger compartment rises, resulting in a problem that the cooling feeling of the occupant is impaired.
[0004]
Therefore, a cold storage means for storing cold when the vehicle engine (compressor) is operated is provided, and when the vehicle engine (compressor) stops and the cooling operation of the evaporator stops, the cold storage means of the cold storage means is used to enter the vehicle interior. There is an increasing need for a regenerative vehicle air conditioner capable of cooling blown air.
[0005]
2. Description of the Related Art As a regenerative air conditioner for a vehicle of this type, one described in Japanese Patent Application Laid-Open No. 2000-313226 has been conventionally known. In this prior art, as shown in FIG. 22, in an air conditioning refrigeration cycle R having a compressor 1 driven by a vehicle engine, a cold storage material 40a is incorporated in parallel with an evaporator 8 for cooling air blown into the vehicle interior. A cold storage heat exchanger 40 is provided.
[0006]
Then, when cold storage is performed during operation of the vehicle engine (compressor 1), the solenoid valve 41 is opened, and the low-pressure refrigerant decompressed by the expansion valve 7 flows in parallel to the evaporator 8 and the cold storage heat exchanger 40. The cold storage material 40a is cooled, and cold storage in the cold storage material 40a is performed.
[0007]
Then, when the compressor 1 is stopped due to the stop of the vehicle engine, the electric pump 42 is operated, and the liquid storage tank 43 → the electromagnetic valve 41 → the electric pump 42 → the cold storage heat exchanger 40 → the evaporator 8 → the liquid storage tank 43 Circulate refrigerant in a closed circuit. The vapor-phase refrigerant evaporated in the evaporator 8 is condensed in the regenerative heat exchanger 40 by the amount of heat stored in the regenerator material 40 a, and the condensed liquid refrigerant is circulated to the evaporator 8. Thus, the cooling operation of the evaporator 8 is continued even when the compressor 1 is stopped, so that the cooling function in the vehicle compartment can be exhibited.
[0008]
Further, in the above-described conventional technique, the electric pump 42 sucks the liquid refrigerant in the liquid storage tank 43 immediately after the vehicle engine is stopped (stopped), that is, immediately after the cooling / cooling mode is started. The suction side of the pump is filled with the liquid refrigerant, and the idling of the electric pump 42 can be prevented.
[0009]
[Problems to be solved by the invention]
By the way, in the above-mentioned conventional technique, a liquid storage tank 43 is arranged on the inlet side of the evaporator 8 and a refrigerant circuit configuration for connecting the electric pump 42 and the cold storage heat exchanger 40 in parallel with the evaporator 8 and the liquid storage tank 43 is provided. Therefore, a three-way branch pipe 44 is interposed between these devices, the liquid storage tank 43 is connected to the branch of the three-way branch pipe 44 on the side of the evaporator 8, and the electric pump 42 and the cold storage heat exchanger 40 are , It must be connected to the branch on the anti-evaporator side of the three-way branch pipe 44. In addition, it is necessary to interpose a solenoid valve 41 for switching the refrigerant flow path between the liquid storage tank 43 and the cold storage heat exchanger 40.
[0010]
As a result, the liquid storage tank 43 occupying a relatively large volume and the cold storage heat exchanger 40 must be necessarily formed separately, and the electric pump 42 also needs to be formed separately from the liquid storage tank 43. There is. Therefore, a dedicated vehicle mounting space is required for each of the electric pump 42, the cold storage heat exchanger 40, and the liquid storage tank 43, and the vehicle mounting performance of the air conditioner deteriorates.
[0011]
Further, in the above-mentioned prior art, an electromagnetic valve 41 is installed in the refrigerant passage on the side of the cold storage heat exchanger 40, and when the cooling capacity is insufficient during operation of the vehicle engine (compressor), the solenoid valve 41 is closed to exchange the cold storage heat. The circulation of the refrigerant to the heat exchanger 40 is stopped, and only when the cooling capacity has a margin, the solenoid valve 41 is opened to circulate the low-pressure refrigerant to the cold-storage heat exchanger 40 to cool the cold storage material 40a. .
[0012]
Therefore, according to the above conventional technology, the solenoid valve 41 for opening and closing the refrigerant passage on the side of the cold storage heat exchanger 40 is essential. In addition, a control mechanism that opens and closes the solenoid valve 41 based on the determination of a cooling capacity shortage state, a margin state, and the like is also essential. As a result, there is a problem that the product cost is significantly increased due to the addition of the cool storage function.
[0013]
Further, in the above-described conventional technology, in the cooling / cooling mode when the vehicle is stopped, the vapor-phase refrigerant evaporated by the evaporator 8 is sent into the cold storage heat exchanger 40, and is cooled and condensed by the cold storage material 40a. The condensed liquid refrigerant accumulates in the cold storage heat exchanger 40, and the cold storage material 40a is immersed in the stored liquid refrigerant. As a result, the heat transfer area where the gas-phase refrigerant flowing into the cold-storage heat exchanger 40 and the cold storage material 40a are in contact with each other is reduced, and the condensing ability of the gas-phase refrigerant is reduced. Accordingly, the flow rate of the liquid refrigerant supplied to the evaporator 8 in the cooling / cooling mode is reduced, and the cooling / cooling capacity is reduced.
[0014]
In addition, in order to solve the above-mentioned problem, it is considered that the cold storage heat exchanger 40 is arranged above the evaporator 8 and the liquid refrigerant in the cold storage heat exchanger 40 is supplied to the evaporator 8 by gravity. However, in the vehicle, there is a mounting restriction that the air-conditioning indoor unit 20 including the evaporator 8 must be mounted in a narrow space such as the inside of an instrument panel (instrument panel) in the vehicle interior. For this reason, arranging the cold storage heat exchanger 40 above the evaporator 8 can hardly be implemented in practice, and is not an effective measure.
[0015]
In view of the above, it is a first object of the present invention to reduce the space for mounting a vehicle in a cold storage type vehicle air conditioner.
[0016]
It is a second object of the present invention to provide a regenerative air conditioner for a vehicle in which a cooling capacity and a regenerative function can be satisfactorily exhibited without requiring an opening / closing function of a refrigerant passage by an electromagnetic valve. I do.
[0017]
Further, a third object of the present invention is to improve the condensation capacity of a gas-phase refrigerant in a cold storage heat exchanger in a cooling / cooling mode in a cold storage type vehicle air conditioner.
[0018]
[Means for Solving the Problems]
The present invention has been devised to achieve the above object, and according to the first aspect of the present invention, a compressor (1) driven by a vehicle engine (4) and a discharge from the compressor (1). The high-pressure side heat exchanger (6) for releasing heat of the high-pressure refrigerant, the pressure reducing means (7, 70) for reducing the pressure of the refrigerant passing through the high-pressure side heat exchanger (6), and the pressure reducing means (7, 70). An evaporator (8) for evaporating the compressed low-pressure refrigerant to cool the air blown into the vehicle interior, and an evaporator (8) provided in series with the evaporator (8). Heat storage heat exchanger (11) having a cold storage material (11a '), and a tank member (10) integrally incorporating at least the cold storage heat exchanger (11) and the pump means for liquid refrigerant circulation (15),
A liquid refrigerant tank (10a) for storing liquid refrigerant is integrally formed below the tank member (10), and when the vehicle engine (4) stops and the compressor (1) stops, the liquid refrigerant tank (10a) stops. ) Is introduced into the evaporator (8) by the pump means (15), and the gaseous phase refrigerant evaporated in the evaporator (8) is introduced into the cold storage heat exchanger (11) to cool the cold storage material (11a '). It is characterized by cooling by cold storage heat and condensing.
[0019]
According to this, since the regenerative heat exchanger (11) is provided in series with the evaporator (8) for cooling the air blown into the vehicle cabin, the compressor (1) operates when the compressor (1) operates. The refrigerant always flows through the series passage of the cold storage heat exchanger (11) and the evaporator (8), thereby exhibiting the cooling capacity of the evaporator (8) and the cold storage material (11a ') of the cold storage heat exchanger (11). Can be stored.
[0020]
Therefore, in the regenerative vehicle air conditioner, the cooling capacity and the regenerative function can be satisfactorily exhibited without requiring the function of opening and closing the refrigerant passage by the electromagnetic valve. When the vehicle engine (4) stops and the compressor (1) stops, the liquid refrigerant at the lower part of the tank member (10) is introduced into the evaporator (8) by the liquid refrigerant circulation pump means (15). Since the vapor-phase refrigerant evaporated in the evaporator (8) can be cooled and liquefied by utilizing the cold storage heat of the cold storage heat exchanger (11), the supply of the liquid refrigerant to the evaporator (8) is continued to provide a cooling function. Can be continued.
[0021]
In addition, the cold storage heat exchanger (11) is provided in series with the evaporator (8), and the cold storage heat exchanger (11) and the pumping means (15) for circulating the liquid refrigerant are connected to a tank member (10) forming a liquid refrigerant tank mechanism. ), The parts corresponding to the cold storage heat exchanger, the electric pump and the liquid storage tank of the prior art can be compactly integrated with one tank member (10), and the mountability on the vehicle can be greatly improved. .
[0022]
According to the second aspect of the present invention, in the first aspect, the cold storage heat exchanger (11) is disposed on the upper side of the inside of the tank member (10), and the pump means (15) is provided below the cold storage heat exchanger (11). ) Is arranged.
[0023]
According to this, the pump means (15) is located on the lower liquid refrigerant tank part (10a) side, and the cold storage heat exchanger (11) is located above the pump means (15). When stopped, that is, in the cooling / cooling mode, the liquid refrigerant condensed in the cold storage heat exchanger (11) can be quickly dropped into the lower liquid refrigerant tank portion (10a) by gravity. Therefore, since the surface of the cold storage heat exchanger (11) does not immerse in the liquid refrigerant, a heat transfer area where the surface of the cold storage material directly contacts the gaseous refrigerant in the cold storage heat exchanger (11) is always secured. it can.
[0024]
This allows efficient heat exchange between the gas-phase refrigerant and the cold storage material, so that the gas-phase refrigerant condensing ability in the cold-storage heat exchanger (11) can always be kept good. Therefore, the cooling and cooling capacity can be satisfactorily secured.
[0025]
According to the second aspect, the cold storage heat exchanger (11) is simply disposed on the upper side inside the tank member (10) in which the liquid refrigerant tank portion (10a) is integrally formed at the lower part. 11) There is no need to arrange itself above the evaporator (9). Therefore, the degree of freedom of the layout is increased when the air conditioner is mounted on a vehicle, which is very advantageous.
[0026]
According to a third aspect of the present invention, in the second aspect, the pump means (15) is disposed so as to be immersed in the liquid refrigerant in the liquid refrigerant tank (10a).
[0027]
Thus, the pump means (15) can be disposed by effectively utilizing the volume of the liquid refrigerant tank (10a), and the overall size of the tank member (10) can be further reduced.
[0028]
Moreover, by immersing the pump means (15) in the liquid refrigerant, the liquid refrigerant can be immediately supplied to the evaporator (8) immediately after the driving of the pump means (15), no matter what time the vehicle stops. Immediately after that, the cooling and cooling function can be effectively used.
[0029]
According to a fourth aspect of the present invention, in any one of the first to third aspects, the outlet passage part (14) connecting the discharge side of the pump means (15) to the inlet side of the evaporator (8) is a tank member. (10) It is arranged inside, and a connection port (14a) is opened in the middle of the outlet passage section (14), and a connection port (14a) is provided in the outlet passage section (14) from the internal space of the tank member (10). A first check valve (13) that allows the flow of the refrigerant only in the direction is arranged.
[0030]
Thereby, in the cooling / cooling mode when the vehicle is stopped, the first check valve (13) is closed by the discharge pressure of the pump means (15), and the liquid refrigerant discharged by the pump means (15) passes through the outlet passage section ( It can be supplied to the inlet side of the evaporator (8) through 14).
[0031]
Further, in the normal cooling / cooling storage mode when the vehicle is running, the refrigerant flow in the forward direction acts on the first check valve (13) due to the refrigerant flow by the operation of the compressor (1), and the first check valve (13). ) Is opened, and the low-pressure refrigerant in the tank member (10) can be introduced to the inlet side of the evaporator (8).
[0032]
According to a fifth aspect of the present invention, in the fourth aspect, the suction opening end (13b, 13b, 13) of the refrigerant drawn into the first check valve (13) from inside the tank member (10) during operation of the compressor (1). 13g) is disposed above the lower end of the cold storage heat exchanger (11).
[0033]
As a result, the liquid refrigerant can be stored up to the portion of the refrigerant suction opening end (13b, 13g) inside the tank member (10). That is, the liquid refrigerant can be stored up to a position above the lower end of the cold storage heat exchanger (11). Therefore, the liquid storage function can be exhibited by utilizing the arrangement space of the cold storage heat exchanger (11), so that the liquid storage space below the cold storage heat exchanger (11) can be significantly reduced, and the tank member (10) can be used. Can be downsized. As a result, the mountability of the cold storage unit including the tank member (10) on the vehicle can be improved.
[0034]
As in the sixth aspect, in the fifth aspect, if the first check valve (13) is disposed above the lower end of the cold storage heat exchanger (11), the refrigerant suction opening end (13b , 13g) can be arranged above the lower end of the cold storage heat exchanger (11) by the arrangement of the first check valve (13) itself.
[0035]
As in the invention according to claim 7, in claim 5, the first check valve (13) is disposed below the regenerative heat exchanger (11), and the inlet of the first check valve (13) ( By connecting a pipe (13f) between 13b) and the suction opening end (13g), the suction opening end (13g) may be arranged above the lower end of the cold storage heat exchanger (11).
[0036]
According to an eighth aspect of the present invention, in any one of the first to third aspects, when the compressor (1) is operated, the refrigerant sucked from inside the tank member (10) is supplied to the inlet side of the evaporator (8). The inlet openings (13b, 13g) of the refrigerant passages (13, 14) to be introduced are arranged above the lower end of the cold storage heat exchanger (11).
[0037]
Thus, the liquid refrigerant can be stored up to a position above the lower end of the cool storage heat exchanger (11), similarly to the fifth aspect. Therefore, the liquid storage space below the cool storage heat exchanger (11) can be significantly reduced, and the tank member (10) can be reduced in size. As a result, the mountability of the cold storage unit including the tank member (10) on the vehicle can be improved.
[0038]
According to the ninth aspect of the present invention, in any one of the fifth to eighth aspects, when the compressor (1) is operated, the refrigerant flowing into the space above the cold storage heat exchanger (11) is cooled by the cold storage heat exchanger (11). The refrigerant flows downward from above 11), and the refrigerant makes a U-turn at the lower part of the cool storage heat exchanger (11) to be sucked into the suction opening ends (13b, 13g).
[0039]
According to the fifth to eighth aspects, the lower part of the cold storage heat exchanger (11) is immersed in the liquid refrigerant, and there is a concern that the heat transfer performance may be reduced due to the immersion in the liquid refrigerant. You. However, in claim 9, when the compressor (1) is operated (cool storage), the refrigerant flows from above the cold storage heat exchanger (11) to below, and at the lower part of the cold storage heat exchanger (11). Is U-turned and is sucked into the suction opening ends (13b, 13g), so that the liquid refrigerant in contact with the lower part of the cool storage heat exchanger (11) is moved downward from above the cool storage heat exchanger (11). It can always flow and stir by the flowing refrigerant flow. Thereby, it is possible to suppress a decrease in heat transfer performance in the liquid refrigerant immersion portion below the cool storage heat exchanger (11).
[0040]
According to a tenth aspect of the present invention, in the ninth aspect, there is provided a partition member (110) for partitioning the periphery of the suction opening end (13b, 13g), and the partition member (110) is provided with a cold storage heat exchanger (11). An opening (113) that opens to the lower part is formed, and the refrigerant in the lower part of the cold storage heat exchanger (11) is taken in from this opening (113) and sucked into the suction opening ends (13b, 13g). And
[0041]
According to this, the U-turn refrigerant flow in claim 9 can be favorably formed by the partitioning action of the partitioning member (110).
[0042]
According to the eleventh aspect of the present invention, in any one of the fifth to tenth aspects, when the vehicle engine (4) stops and the compressor (1) stops, the cold storage heat exchanger (11) operates. The discharge capacity of the pump means (15) is set so that the liquid refrigerant circulating flow rate by the pump means (15) is larger than the amount of condensed refrigerant.
[0043]
According to the fifth to tenth aspects, the lower part of the regenerative heat exchanger (11) is immersed in the liquid refrigerant, so that when the compressor (1) is stopped (during cooling), this liquid refrigerant is cooled. There is a concern that the heat transfer performance may be reduced due to immersion in the inside. However, in the tenth aspect, by setting the discharge capacity of the pump means (15) as described above, the liquid level of the liquid refrigerant when the compressor (1) is stopped (during cooling) can be reduced. ) Can be pulled down below the lower end.
[0044]
Thereby, the gas-phase refrigerant refluxed from the evaporator outlet can be cooled and condensed by the whole regenerative heat exchanger (11). Therefore, it is possible to prevent the cooling ability from lowering.
[0045]
In the twelfth aspect of the present invention, in any one of the first to eleventh aspects, the pressure reducing means is an expansion valve (7) for adjusting a refrigerant flow rate according to the degree of superheat of the refrigerant at the outlet of the evaporator (8). Yes, the regenerative heat exchanger (11) is provided on the refrigerant inlet side of the evaporator (8).
[0046]
When the cold storage to the cold storage material (11a ') is completed in the cold storage heat exchanger (11), the low-pressure refrigerant passes through the cold storage heat exchanger (11) almost without absorbing heat. When the exchanger (11) is provided on the refrigerant outlet side of the evaporator (8), the refrigerant at the evaporator outlet is cooled by the cold storage material (11a ') whose cold storage is completed, and the refrigerant flow rate adjustment by the expansion valve (7) is appropriately performed. Can not be performed.
[0047]
However, according to the twelfth aspect, since the regenerative heat exchanger (11) is provided on the refrigerant inlet side of the evaporator (8), the expansion valve (7) does not include the regenerative heat exchanger (11). Similar to the cycle, the refrigerant flow rate can be appropriately adjusted according to the degree of superheat of the evaporator outlet refrigerant.
[0048]
According to a thirteenth aspect, in the twelfth aspect, the refrigerant inflow portion (12) from the outlet of the expansion valve (7) to the tank member (10) and the tank member (10) from the outlet of the evaporator (8). The refrigerant inflow portion (16) into the cold storage heat exchanger (11) is disposed above the cold storage heat exchanger (11).
[0049]
This allows the low-pressure refrigerant from the outlet of the expansion valve (7) to flow smoothly from the upper part of the cool storage heat exchanger (11) downward along the direction of gravity in the normal cooling / cooling mode when the vehicle is running. Similarly, in the cooling / cooling mode when the vehicle is stopped, the gas-phase refrigerant from the outlet of the evaporator (8) can flow downward along the direction of gravity from the top of the cold storage heat exchanger (11). The liquid refrigerant cooled and condensed on the surface of the heat exchanger (11) can be smoothly dropped downward by gravity.
[0050]
According to a fourteenth aspect of the present invention, in the thirteenth aspect, the refrigerant inflow portion (16) from the outlet of the evaporator (8) is provided only in one direction from the outlet of the evaporator (8) to the tank member (10). A second check valve (18) that allows the flow of the refrigerant is provided.
[0051]
Thereby, in the cooling / cooling mode when the vehicle is stopped, the pressure of the refrigerant from the outlet of the evaporator (8) acts on the second check valve (18) in the forward direction to open the second check valve (18). Therefore, the refrigerant from the outlet of the evaporator (8) can flow into the upper part of the cold storage heat exchanger (11). On the other hand, in the normal cooling / cooling mode when the vehicle is traveling, the refrigerant pressure in the tank member (10) acts on the second check valve (18) in the opposite direction, and the second check valve (18) closes. The refrigerant in the tank member (10) can be prevented from flowing directly to the outlet side of the evaporator (8).
[0052]
In the invention according to claim 15, a compressor (1) driven by a vehicle engine (4), a high-pressure side heat exchanger (6) for radiating heat of the high-pressure refrigerant discharged from the compressor (1), A decompression means (70) for decompressing the refrigerant passing through the high-pressure side heat exchanger (6); and an evaporator (70) for evaporating the low-pressure refrigerant decompressed by the decompression means (70) and cooling the air blown into the vehicle interior. 8), and a tank member (10) disposed on the refrigerant outlet side of the evaporator (8) and integrally forming a liquid refrigerant tank portion (10a) for storing liquid refrigerant at a lower portion thereof. Gas-liquid of the low-pressure refrigerant at the outlet of the evaporator (8) is separated inside, and the gas-phase refrigerant is discharged to the suction side of the compressor (1).
During operation of the compressor (1), the cold storage heat exchanger (11) having the cold storage material (11a ') cooled by the low-pressure refrigerant after passing through the evaporator (8) and the liquid refrigerant circulation pump means (15) At least when the compressor (1) is stopped by stopping the vehicle engine (4) integrally with the tank member (10), the liquid refrigerant in the liquid refrigerant tank (10a) is evaporated by the pump means (15). (8), the vapor-phase refrigerant evaporated in the evaporator (8) is introduced into the cold storage heat exchanger (11), and cooled and condensed by the cold storage heat of the cold storage material (11a '). .
[0053]
The tank member (10) according to claim 15 functions as a refrigerant gas-liquid separator generally called an accumulator, whereby the compression can be performed without using the expansion valve (7) as the pressure reducing means. It is possible to prevent the return of the liquid refrigerant to the machine (1), and hence the liquid compression. In the case where the expansion valve (7) is not used as the pressure reducing means, even if the regenerative heat exchanger (11) is provided on the refrigerant outlet side of the evaporator (8), the operation of adjusting the refrigerant flow rate in the cycle will not be affected.
[0054]
Further, since the low-pressure refrigerant that has passed through the cold storage heat exchanger (11) passes through the inside of the tank member (10) and is sucked into the compressor (1), the low-pressure refrigerant is cooled by the cooling operation of the cold storage heat exchanger (11). Even if is liquefied, the liquid refrigerant can be stored in the liquid refrigerant tank (10a) below the tank member (10).
[0055]
The low-pressure refrigerant temperature on the refrigerant outlet side of the evaporator (8) is lower than that on the refrigerant inlet side by the pressure loss in the refrigerant flow path of the evaporator (8). 11a '), the temperature difference with the heat storage material (11a') can be efficiently cooled.
[0056]
In addition, according to the present invention, the cold storage heat exchanger (11) and the pump means (15) are integrated into the tank member (10) which performs the accumulator function, and the liquid refrigerant tank portion ( By integrally forming 10a), the vehicle mountability can be improved as in the first aspect.
[0057]
According to a sixteenth aspect of the present invention, in the fifteenth aspect, the cool storage heat exchanger (11) is disposed on the upper side of the inside of the tank member (10), and the pump means (15) is provided below the cool storage heat exchanger (11). ) Is arranged.
[0058]
Thus, in the apparatus using the tank member (10) performing the accumulator function, the same effect as in the second aspect can be exhibited.
[0059]
According to a seventeenth aspect, in the sixteenth aspect, the pump means (15) is arranged so as to be immersed in the liquid refrigerant in the liquid refrigerant tank (10a).
[0060]
Thereby, the same effect as the third aspect can be exhibited.
[0061]
In the invention according to claim 18, in any one of claims 15 to 17, the refrigerant inflow portion (120) from the outlet of the evaporator (8) to the tank member (10) is provided as a cold storage heat exchanger (11). It is characterized by being arranged on the upper part of the.
[0062]
Thereby, the refrigerant from the outlet of the evaporator (8) can flow smoothly from the upper part of the cold storage heat exchanger (11) downward along the direction of gravity.
[0063]
According to the nineteenth aspect, in any one of the fifteenth to eighteenth aspects, there is provided an outlet passage part (142) connecting a discharge side of the pump means (15) to an inlet side of the evaporator (8), A check valve (18) is provided in the outlet passage (142) to allow the flow of the refrigerant only in one direction from the pump means (15) to the inlet side of the evaporator (8).
[0064]
Accordingly, in the cooling / cooling mode when the vehicle is stopped, the discharge pressure of the pump means (15) acts on the check valve (18) in the forward direction to open the check valve (18), so that the pump means (15) Can be supplied to the inlet side of the evaporator (8) through the outlet passage (142). On the other hand, in the normal cooling / cooling mode when the vehicle is running, the refrigerant pressure on the inlet side of the evaporator (8) acts on the check valve (18) in the opposite direction to close the check valve (18). The refrigerant on the inlet side of the vessel (8) can be prevented from directly flowing into the tank member (10) that performs the function of an accumulator.
[0065]
The first check valve (13) of claim 4, the second check valve (18) of claim 14, and the check valve (18) of claim 19 are significantly lower in cost than solenoid valves. It is small and practically advantageous.
[0066]
According to the twentieth aspect, the compressor (1) driven by the vehicle engine (4) and the low-pressure refrigerant decompressed by the decompression means (7, 70) are evaporated to supply air blown into the vehicle interior. A cold storage heat exchanger applied to a vehicle air conditioner including a refrigeration cycle (R) including an evaporator (8) for cooling, wherein a tube (11e) through which a refrigerant of the refrigeration cycle (R) flows; A fin (11f) thermally integrated with (11e) and constituting an enlarged heat transfer surface of the tube (11e); and a shell (11d) for accommodating a combined body of the tube (11e) and the fin (11f). When the compressor (1) is in operation, the compressor (1) is cooled by a low-temperature refrigerant passing through the tube (11e) to perform cold storage, and when the compressor (1) is stopped, the evaporator (8) is stored. ) 'A, the cold storage material (11a cold accumulating material to be condensed cooled by cold storage heat refrigerant (11a)', characterized in that filling) as a thin film between the heat-transfer surface mutual fins (11f).
[0067]
As described above, in the cold storage heat exchanger configuration in which the cold storage material (11a ') is filled in a thin film shape between the heat transfer surfaces of the fins (11f), even if the thermal conductivity of the cold storage material (11a') is small. The heat can be efficiently exchanged between the fin (11f) and the cold storage material (11a '). As a result, as is apparent from the comparative study of the present inventor shown in FIG. 17 to be described later, compared with the case where the cold storage material (11a ′) is filled in a cylindrical or ball-shaped container, the cold storage heat exchanger is used. The size can be significantly reduced.
[0068]
According to a twenty-first aspect of the present invention, in the twentieth aspect, the tube (11e) is arranged in a vertical direction, and the refrigerant flows through the tube (11e) from above to below.
[0069]
According to this, when the gas-phase refrigerant is cooled by the regenerator material (11a ') and condenses in the tube (11e) when the compressor is stopped (during cooling), the refrigerant in the tube (11e) moves downward from above. Therefore, the condensed liquid can be quickly discharged out of the tube by gravity along the flow of the refrigerant. Therefore, the condensed liquid film on the inner surface of the tube (11e) is always kept thin so that the heat transfer performance at the time of cooling can be favorably maintained.
[0070]
As in the invention of the twenty-second aspect, in the twentieth or twenty-first aspect, the fins (11f) can be specifically formed of flat fins arranged substantially in parallel at a predetermined fin pitch.
[0071]
Like the invention according to claim 23, the flat fin (11f) according to claim 22 is more specifically configured by a plurality of fins stacked at a predetermined fin pitch.
[0072]
According to a twenty-fourth aspect of the present invention, in the twenty-second aspect, the tube (11e) is formed in a tubular shape, and the plate-like fins (11f) are integrally formed continuously and spirally on the outer peripheral surface of the tube (11e). May be.
[0073]
According to this, since the fins can be integrally formed in a spiral shape on the outer peripheral surface of the tube in advance, the assembling work of the heat exchanger can be simplified.
[0074]
According to a twenty-fifth aspect of the present invention, in any one of the twenty-second to twenty-third aspects, the fin pitch is set in a range of 0.5 mm to 2.0 mm.
[0075]
According to the study of the present inventor, by setting the fin pitch within the above range, it is possible to ensure the heat transfer performance of the regenerative heat exchanger and to achieve a good reduction in the size of the regenerative heat exchanger.
[0076]
According to a twenty-sixth aspect of the present invention, in any one of the twentieth to twenty-fifth aspects, the fin (11f) is provided with a through hole (11n) that allows movement of the cold storage material (11a ′) according to a volume change. Features.
[0077]
By the way, when the cold storage material (11a ') undergoes a phase change from a liquid phase to a solid phase during operation of the compressor (cool storage), the volume of the cold storage material (11a') decreases. The cold storage material (11a ') can be easily supplied between the fins from outside the fins through (11n).
[0078]
On the other hand, when the cold storage material (11a ') changes from a solid phase to a liquid phase when the compressor is stopped (cooling), the volume of the cold storage material (11a') increases, but the fins pass through the through holes (11n). The cold storage material (11a ') can be easily extruded from the space to the outside of the fin.
[0079]
As described above, the movement of the cold storage material (11a ') accompanying the change in the volume of the cold storage material (11a') can be easily performed. The generation of excessive stress can be avoided, and the durability of the cold storage heat exchanger can be improved.
[0080]
According to a twenty-seventh aspect of the present invention, in any one of the twentieth to twenty-fifth aspects, a gap (11p) for heat insulation is provided between the shell (11d) and the fin (11f).
[0081]
By the way, the temperature near the inner wall surface of the shell (11d) rises above the melting point of the cold storage material (11a ') due to the invasion of heat from the outside of the shell, and the cold storage material (11a') is normally maintained in a liquid phase. Moreover, advantageously, the thermal conductivity of the cold storage material (11a ') is much smaller in the liquid state than in the solid state.
[0082]
Therefore, in the twenty-seventh aspect, the cold storage material (11a ') located in the gap portion (11p) of the inner peripheral portion of the shell (11d) is maintained in a liquid phase state, and the low thermal conductivity of the cold storage material itself is effectively utilized. As a result, the heat insulation effect can be effectively exhibited.
[0083]
As a result, the cooling loss can be significantly reduced without providing a special heat insulating structure. Further, even when the heat insulating structure is provided, the amount of heat insulating material used can be significantly reduced.
[0084]
In addition, the code | symbol in the parenthesis of each said means shows the correspondence with the concrete means described in embodiment mentioned later.
[0085]
BEST MODE FOR CARRYING OUT THE INVENTION
(1st Embodiment)
FIG. 1 shows a refrigeration cycle R of the vehicle air conditioner according to the first embodiment. The refrigeration cycle R of the vehicle air conditioner has a compressor 1 that sucks, compresses, and discharges refrigerant, and the compressor 1 is provided with an electromagnetic clutch 2 for intermittent power. Since the power of the vehicle engine 4 is transmitted to the compressor 1 via the electromagnetic clutch 2 and the belt 3, the operation of the compressor 1 is interrupted by interrupting the energization of the electromagnetic clutch 2 by the air-conditioning control device 5. You.
[0086]
The high-temperature, high-pressure superheated gas-phase refrigerant discharged from the compressor 1 flows into a condenser 6 serving as a high-pressure side heat exchanger, exchanges heat with outside air blown from a cooling fan (not shown), and is cooled and condensed. The condenser 6 includes a condenser 6a, a receiver 6b that separates gas and liquid of the refrigerant after passing through the condenser 6a, stores the liquid refrigerant, and outputs the liquid refrigerant, and a liquid refrigerant from the liquid receiver 6b. It is a well-known structure in which a supercooling unit 6c for supercooling is integrally formed.
[0087]
The supercooled liquid refrigerant from the supercooling section 6c is reduced in pressure to a low pressure by the expansion valve 7 serving as a pressure reducing means, and enters a low-pressure gas-liquid two-phase state. The expansion valve 7 is a temperature-type expansion valve that adjusts the opening degree (refrigerant flow rate) of the valve 7a so as to adjust the degree of superheating of the refrigerant at the outlet of the evaporator 8 that forms a heat exchanger for cooling. In particular, in this example, the evaporator outlet refrigerant passage 7b through which the outlet refrigerant of the evaporator 8 flows is formed in the box-shaped housing 7c, and the outlet refrigerant temperature-sensing mechanism of the evaporator 8 is integrally formed in the housing 7c. A thermal expansion valve 7 of the type is used.
[0088]
The regenerative storage unit 9 is one in which the devices within the two-dot chain line frame in FIG. 1 are integrally formed inside one tank member 10 shown in FIG. 2, and the tank member 10 has a cylindrical shape extending in the vertical direction. A liquid refrigerant tank 10a for storing a low-temperature low-pressure liquid refrigerant is integrally formed at a lower portion thereof.
[0089]
Further, inside the tank member 10, a cold storage heat exchanger 11 is configured above the liquid refrigerant tank portion 10a. Specifically, the regenerative heat exchanger 11 includes a plurality of regenerator containers 11a in which regenerator materials 11a 'are sealed, in such a state that a gap is formed between the containers to allow a refrigerant to flow. Holding plates 11b and 11c having refrigerant circulation holes are arranged on the upper and lower sides of the plurality of cold storage material containers 11a, and the outer peripheral portions of the holding plates 11b and 11c are fixed to the inner wall surface of the tank member 10.
[0090]
Here, the form of the cold storage material container 11a is specifically a cylindrical (stick) type having a cylindrical shape elongated in the refrigerant flow direction shown in FIG. 3A, a ball type shown in FIG. Any of the capsule types shown in FIG. 3 (c) may be used. The cold storage material container 11a can be formed of a thin film pack member made of resin or a metal plate material such as aluminum.
[0091]
The regenerative material 11a 'sealed in the regenerator material container 11a is a material that can be cooled by a low-pressure refrigerant and undergo a phase change (liquid phase to solid phase) to accumulate latent heat of solidification, that is, a material that solidifies at a temperature higher than the low-pressure refrigerant temperature. Select the material to be used.
[0092]
Here, the low-pressure refrigerant temperature is usually controlled to a temperature of about 3 to 4 ° C. in order to prevent frost in the evaporator 8, and the target upper limit temperature of the air discharged from the vehicle interior during cooling is to ensure the cooling feeling. The temperature is usually set to about 12 ° C. to 15 ° in order to prevent bad odor from the evaporator 8 and the like.
[0093]
Therefore, as the cold storage material 11a ', a material whose freezing point is located between the low-pressure refrigerant temperature and the target upper limit temperature of the blowing air temperature during cooling is preferable, and specifically, a paraffin having a freezing point of about 6 to 8 ° C. Is optimal. Of course, if the low-pressure refrigerant temperature is controlled to 0 ° C. or less, water (ice) can be used as the cold storage material 11a ′.
[0094]
In order to maintain the cold storage state (solidified state) of the cold storage material 11a ', it is necessary to maintain the inside of the tank member 10 in a low temperature state below the freezing point of the cold storage material 11a', so the tank member 10 is configured as an adiabatic tank. There is a need. Therefore, as the tank member 10, a resin tank having excellent heat insulating properties, a material obtained by attaching a heat insulating material to the surface of a metal tank, or the like is used.
[0095]
The regenerative heat exchanger 11 may be configured as a shell-and-tube type heat exchanger. In this case, the cycle low-pressure refrigerant flows through a tube disposed inside the shell (tank), and the shell (tank) The inside of the tube may be filled with the cold storage material 11a 'inside and cooled by the cycle low-pressure refrigerant.
[0096]
Next, the connection relationship between the regenerative storage unit 9 and the refrigeration cycle refrigerant passage will be described. An inlet pipe through which a low-temperature low-pressure refrigerant, which has been depressurized and passed through the valve portion 7a of the expansion valve 7, flows into the upper surface of the tank member 10. 12 are arranged. The inlet pipe 12 constitutes a refrigerant inflow portion, and a low-temperature low-pressure refrigerant flows into the upper surface of the cold storage heat exchanger 11 in the tank member 10 from the inlet pipe 12.
[0097]
In the tank member 10, a first check valve 13 is arranged on a lower surface portion of the cold storage heat exchanger 11. The inlet 13b of the first check valve 13 is always in communication with the space below the regenerative heat exchanger 11, and the refrigerant pressure in the direction from the inlet 13b to the outlet 13c with respect to the valve body 13a of the first check valve 13. When acting, the valve body 13a is separated from the valve seat 13d to be in an open state. Conversely, when the refrigerant pressure acts on the valve body 13a in a direction from the outlet 13c to the inlet 13b, the valve body 13a is pressed against the valve seat 13d to close the valve. The stopper 13e defines a fully open position of the valve 13a.
[0098]
At the center of the tank member 10, an outlet pipe 14 forming an outlet passage is disposed so as to extend vertically through the center of the cold storage heat exchanger 11. The upper end of the outlet pipe 14 passes through the upper surface of the tank member 10 and is taken out of the tank, and is connected to the inlet of the evaporator 8 as shown in FIG.
[0099]
On the other hand, the lower end of the outlet pipe 14 hangs down to the liquid refrigerant storage area of the liquid refrigerant tank 10a, and the lower end of the outlet pipe 14 is provided with an electric pump 15 serving as a pump means for circulating the liquid refrigerant. . The electric pump 15 is provided with a suction port 15a on the bottom side thereof, sucks the liquid refrigerant in the liquid refrigerant tank 10a from the suction port 15a, and circulates it through the outlet pipe 14 to the evaporator 8.
[0100]
The outlet pipe 14 has a connection port 14a opened at an intermediate portion in the vertical direction, and the outlet 13c of the first check valve 13 is connected to the connection port 14a. Therefore, a refrigerant passage is formed from the outlet passage of the valve portion 7a of the expansion valve 7 to the inlet of the evaporator 8 through the inlet pipe 12, the cold storage heat exchanger 11, the first check valve 13, and the outlet pipe 14, and the cold storage The heat exchanger 11 is provided in series with the inlet side passage of the evaporator 8.
[0101]
Further, on the upper surface of the tank member 10, there is provided a refrigerant return pipe 16 serving as a refrigerant inflow portion for allowing the refrigerant from the outlet of the evaporator 8 to flow into the tank member 10. One end (upper end) of the refrigerant return pipe 16 is connected to an outlet refrigerant pipe 17 of the evaporator 8, and the other end (lower end) of the refrigerant return pipe 16 penetrates through the upper surface of the tank member 10 to form a tank. It is connected to a second check valve 18 arranged in the member 10.
[0102]
More specifically, the outlet refrigerant pipe 17 of the evaporator 8 is connected to the evaporator outlet refrigerant passage 7b inside the expansion valve 7, and the refrigerant is located upstream of the evaporator outlet refrigerant passage 7b. One end of the return pipe 16 is connected to the outlet refrigerant pipe 17. Further, a second check valve 18 is arranged at the uppermost part of the space in the tank member 10, and an inlet 18 b of the second check valve 18 is connected to the other end (lower end) of the refrigerant return pipe 16. The outlet 18c of the second check valve 18 is arranged to face the upper surface of the cold storage heat exchanger 11.
[0103]
The second check valve 18 is similar to the first check valve 13. When the refrigerant pressure acts on the valve body 18 a of the second check valve 18 from the inlet 18 b to the outlet 18 c, 18a is separated from the valve seat 18d to be in a valve-open state. Conversely, when the refrigerant pressure acts on the valve element 18a in the direction from the outlet 18c to the inlet 18b, the valve element 18a is pressed against the valve seat 18d and is closed. The stopper 18e defines a fully open position of the valve element 18a.
[0104]
In this example, the expansion valve 7 is arranged on the upper surface of the tank member 10 of the cold storage unit 9, the expansion valve 7 is also integrated as a part of the cold storage unit 9, and the expansion valve 7 and the cold storage unit 9 are integrated. It is designed to be mounted on.
[0105]
In order to maintain the low temperature state inside the tank member 10, it is better for the cold storage unit 9 to suppress the intrusion of heat into the tank member 10 as much as possible. For this purpose, it is better to install the cold storage unit 9 inside the vehicle compartment, for example, inside the instrument panel at the front of the vehicle compartment. However, when it is not possible to secure a mounting space for the cool storage unit 9 in the vehicle compartment due to space restrictions in the vehicle compartment, the cool storage unit 9 is installed outside the vehicle compartment, for example, in an engine room.
[0106]
FIG. 4 shows the air-conditioning indoor unit 20. The air-conditioning indoor unit 20 is usually mounted inside the instrument panel at the front of the vehicle cabin. The air-conditioning case 21 of the air-conditioning indoor unit 20 constitutes a passage for air blown toward the vehicle interior, and the evaporator 8 is installed in the air-conditioning case 21.
[0107]
In the air conditioning case 21, a blower 22 is disposed upstream of the evaporator 8, and the blower 22 is provided with a centrifugal blower fan 22a and a drive motor 22b. An inside / outside air switching box 23 is arranged on the suction side of the blower fan 22a, and outside air (outside air) or inside air (inside air) is selectively introduced through an inside / outside air switching door 23a in the inside / outside air switching box 23.
[0108]
An air mixing door 24 is disposed downstream of the evaporator 8 in the air conditioning case 21, and a hot water type that heats air using hot water (cooling water) of the vehicle engine 4 as a heat source is disposed downstream of the air mixing door 24. The heater core 25 is provided as a heat exchanger for heating.
[0109]
A bypass passage 26 is formed on the side (upper portion) of the hot water heater core 25 to flow air (cold air) bypassing the hot water heater core 25. The air mix door 24 is a rotatable plate-like door, and adjusts the flow rate of the hot air passing through the hot water heater core 25 and the cool air passing through the bypass passage 26. The temperature of the air blown into the cabin is adjusted by adjusting the temperature. Therefore, the air mix door 24 constitutes a means for adjusting the temperature of the air blown into the vehicle interior.
[0110]
The hot air from the hot-water heater core 25 and the cold air from the bypass passage 26 are mixed in the air mixing section 27 to produce air at a desired temperature. Further, in the air-conditioning case 21, a blowing mode switching unit is configured downstream of the air mixing unit 27. That is, a defroster opening 28 that blows air to the inner surface of the vehicle windshield, a face opening 29 that blows air toward the upper body side of the passenger in the passenger compartment, and a foot opening 30 that blows air toward the feet of the passenger in the passenger compartment. It is opened and closed by mode doors 31-33.
[0111]
The temperature sensor 34 of the evaporator 8 is disposed in the air conditioning case 21 at a position immediately after the air is blown out of the evaporator 8 and detects the evaporator blowout temperature Te. Here, the evaporator outlet temperature Te detected by the evaporator temperature sensor 34 is, as in a normal air conditioner, the intermittent control of the electromagnetic clutch 2 of the compressor 1 or the case where the compressor 1 is of a variable displacement type. The cooling capacity of the evaporator 8 is adjusted by the clutch engagement / disengagement control and the discharge capacity control to control the blowing temperature of the evaporator 8.
[0112]
As shown in FIG. 1, in addition to the temperature sensor 34, the air-conditioning control device 5 detects an internal temperature Tr, an external temperature Tam, a solar radiation amount Ts, a hot water temperature Tw, and the like for air-conditioning control. The detection signal is input from the sensor group 35 of. Further, an operation signal of an operation switch group of an air conditioning control panel 36 installed near the instrument panel in the vehicle compartment is also input to the air conditioning control device 5.
[0113]
The air-conditioning control panel 36 includes various operation switches (shown in the figure) such as a temperature setting switch, an air volume changeover switch, a blowout mode switch, an inside / outside air changeover switch, and an air conditioner switch for generating an on / off signal of the compressor 1 which are manually operated by an occupant. ) Are provided.
[0114]
The air-conditioning control device 5 is connected to the engine control device 37, and the engine control device 37 inputs a rotation speed signal and a vehicle speed signal of the vehicle engine 4 to the air-conditioning control device 5.
[0115]
As is well known, the engine control device 37 comprehensively controls a fuel injection amount, an ignition timing, and the like to the vehicle engine 4 based on a signal from a sensor group 38 that detects an operation state of the vehicle engine 4 and the like. Further, in the eco-run vehicle to which the present embodiment is applied, when the stop state is determined based on the rotation speed signal, the vehicle speed signal, the brake signal, and the like of the vehicle engine 4, the engine control device 37 turns off the ignition device, The vehicle engine 4 is automatically stopped by stopping fuel injection or the like.
[0116]
Further, after the engine is stopped, when the vehicle shifts from the stopped state to the start state by the driver's driving operation, the engine control device 37 determines the start state of the vehicle based on an accelerator signal or the like, and automatically turns the vehicle engine 4 on. To start. Note that the air-conditioning control device 5 performs the cooling / cooling mode after the vehicle engine 4 is stopped for a long time, and when the cooling by the cold storage heat amount of the cold storage heat exchanger 11 cannot be continued, that is, the evaporator When the blowout temperature Te rises to a predetermined target upper limit temperature, a signal of an engine restart request is output to the engine control device 37.
[0117]
The air-conditioning control device 5 and the engine control device 37 are configured by a known microcomputer including a CPU, a ROM, a RAM, and the like, and peripheral circuits thereof. The air-conditioning control device 5 and the engine control device 37 may be integrated as one control device.
[0118]
Next, the operation of the first embodiment in the above configuration will be described. FIG. 5 shows the operation in the normal cooling / cooling mode when the vehicle is running. In this normal cooling / cooling mode, the compressor 1 is driven by the vehicle engine 4 to operate the refrigeration cycle R.
[0119]
Accordingly, the high-pressure gas-phase refrigerant discharged from the compressor 1 is cooled by the condenser 6, turns into a supercooled liquid refrigerant, and flows into the expansion valve 7. The high-pressure liquid refrigerant is decompressed by the valve portion 7a of the expansion valve 7 to be in a low-temperature low-pressure gas-liquid two-phase state, and flows into the tank member 10 of the cool storage unit 9 from the inlet pipe 12. This inflow refrigerant flows downward from the upper surface of the cold storage heat exchanger 11 through the gap between the multiple cold storage material containers 11 a in the tank member 10.
[0120]
Here, the refrigerant pressure acts on the valve body 13a of the first check valve 13 located on the lower surface of the cold storage heat exchanger 11 in the direction from the inlet 13b to the outlet 13c (forward direction), and the first check is performed. Since the valve 13 is opened, the lower space of the regenerative heat exchanger 11 communicates with the connection port 14 a at the intermediate portion of the outlet pipe 14 via the first check valve 13.
[0121]
In addition, in the normal cooling / cooling mode, the operation of the electric pump 15 for circulating the liquid refrigerant is unnecessary, and the electric pump 15 is stopped by the output of the air conditioning control device 5. For this reason, the electric pump 15 becomes a flow resistance, and the amount of the refrigerant in the lower space of the cool storage heat exchanger 11 flowing into the lower end portion of the outlet pipe 14 via the electric pump 15 is small.
[0122]
Therefore, most of the refrigerant in the lower space of the cool storage heat exchanger 11 flows into the connection port 14 a in the middle of the outlet pipe 14 via the first check valve 13. At this time, the refrigerant pressure acts on the valve element 18a of the second check valve 18 in the direction (reverse direction) from the outlet 18c to the inlet 18b, and the second check valve 18 maintains the closed state.
[0123]
The low-pressure refrigerant that has flowed into the outlet pipe 14 flows into the inlet of the evaporator 8, and in the evaporator 8, absorbs heat from the blast air in the air conditioning case 21 and evaporates to become a gas-phase refrigerant. The gas-phase refrigerant is sucked into the compressor 1 through the outlet refrigerant pipe 17 of the evaporator 8 and the evaporator outlet refrigerant passage 7b inside the expansion valve 7, and is compressed again. The cool air absorbed by the evaporator 8 blows out from the face opening 29 and the like into the vehicle interior to cool the interior of the vehicle.
[0124]
Next, the behavior of the refrigerant inside the tank member 10 of the cool storage unit 9 in the normal cooling / cool storage mode will be described more specifically. When the cooling is started at a high outside air temperature in summer, the suction air of the evaporator 8 is used. The temperature becomes as high as 40 ° C. or more, and the cooling heat load of the evaporator 8 becomes very large. Under such high cooling load conditions, the degree of superheat of the refrigerant at the outlet of the evaporator 8 is excessive, the opening of the valve portion 7a of the expansion valve 7 is fully opened, and the low pressure of the refrigeration cycle increases.
[0125]
Therefore, the temperature of the low-pressure refrigerant flowing into the cold storage heat exchanger 11 of the cold storage unit 9 becomes higher than the freezing point (about 6 to 8 ° C.) of the cold storage material 11 a ′ of the cold storage heat exchanger 11. Therefore, the cold storage material 11a 'does not solidify due to heat exchange with the low-pressure refrigerant, but only absorbs sensible heat from the cold storage material 11a'. As a result, the amount of heat absorbed by the low-pressure refrigerant in the cold storage heat exchanger 11 under a high cooling load condition is very small. Therefore, most of the low-pressure refrigerant absorbs heat from the air blown out of the passenger compartment in the evaporator 8 and evaporates in the same manner as in a normal air conditioner without the cool storage heat exchanger 11.
[0126]
At the time of high cooling load, the inside air mode in which the inside air is sucked from the inside / outside air switching box 23 in FIG. 4 is usually selected, so that the temperature of the intake air of the evaporator 8 decreases with the lapse of time after the start of cooling, and the cooling heat The load decreases. As a result, the degree of superheat of the refrigerant at the outlet of the evaporator 8 decreases, so that the opening of the valve portion 7a of the expansion valve 7 decreases, the low pressure of the refrigeration cycle decreases, and the low pressure refrigerant temperature decreases.
[0127]
When the low-pressure refrigerant temperature falls below the freezing point of the cold storage material 11a 'of the cold storage heat exchanger 11, the cold storage material 11a' starts to solidify, and the low-pressure refrigerant absorbs the solidification latent heat from the cold storage material 11a '. The endotherm from 'increases. However, at the time when the cold storage material 11a 'has reached the stage of storing the solidification latent heat in this way, the low-pressure refrigerant temperature has already been sufficiently reduced due to the decrease in the cooling heat load, and the air discharged from the passenger compartment has been sufficiently reduced.
[0128]
Therefore, the rapid cooling performance (cool-down performance) under the high cooling load condition is not significantly impaired by the cold storage effect of the latent heat of solidification on the cold storage material 11a '. In other words, even if the cool storage heat exchanger 11 is connected in series to the refrigerant circuit of the cooling evaporator 8, the rapid cooling performance under a high cooling load condition is reduced only by a small amount and can be sufficiently exhibited.
[0129]
Then, when the cooling heat load decreases and the cold storage material 11a 'solidifies, the circulating refrigerant flow rate in the cycle decreases, the refrigerant flow rate in the tank member 10 of the cold storage unit 9 decreases, and the gas-liquid two-phase state , The gas-liquid separation of the low-pressure refrigerant easily occurs. As a result, the liquid refrigerant drops due to gravity and gradually accumulates in the liquid refrigerant tank portion 10a formed below the tank member 10.
[0130]
FIG. 2 shows a state where the maximum amount of the liquid refrigerant is stored in the liquid refrigerant tank 10a. That is, when the liquid level of the stored liquid refrigerant in the liquid refrigerant tank 10 a rises and reaches the installation height of the first check valve 13, the liquid refrigerant in the liquid refrigerant tank 10 a evaporates through the first check valve 13. The liquid level of the stored liquid refrigerant does not rise from the installation height of the first check valve 13 because the liquid refrigerant is sent to the vessel 8. In other words, the first check valve 13 plays a role in determining the maximum amount of the stored liquid refrigerant.
[0131]
Next, a case where the vehicle engine 4 is automatically stopped when the vehicle stops at a traffic light or the like will be described. The R compressor 1 is also forcibly stopped. Therefore, the air-conditioning control device 5 determines whether the engine (compressor) is stopped when the vehicle is stopped, supplies power to the electric pump 15 in the cool storage unit 9, and operates the electric pump 15.
[0132]
As a result, the electric pump 15 sucks the liquid refrigerant stored in the liquid refrigerant tank portion 10 a below the tank member 10, and discharges the liquid refrigerant to the inlet side of the evaporator 8 via the outlet pipe 14. By the suction and discharge of the liquid refrigerant by the electric pump 15, the refrigerant pressure acts on the first check valve 13 in the reverse direction, and the first check valve 13 closes. On the other hand, the refrigerant pressure acts on the second check valve 18 in the forward direction, and the second check valve 18 opens.
[0133]
Therefore, as shown by the arrow in FIG. 6, the liquid refrigerant tank 10a → the electric pump 15 → the outlet pipe 14 → the evaporator 8 → the outlet refrigerant pipe 17 → the refrigerant return pipe 16 → the second check valve 18 → the cold storage heat exchanger 11 → The refrigerant circulates in the refrigerant circuit composed of the liquid refrigerant tank 10a.
[0134]
Therefore, in the evaporator 8, the liquid refrigerant from the liquid refrigerant tank portion 10a absorbs heat from the air blown by the blower 22 and evaporates, so that the cooling operation of the evaporator 8 can be continued even after the compressor is stopped, and the cooling operation in the vehicle compartment Can be continued. Since the temperature of the vapor phase refrigerant evaporated in the evaporator 8 is higher than the freezing point of the cold storage material 11a 'of the cold storage heat exchanger 11, the cold storage material 11a' absorbs the latent heat of fusion from the gas phase refrigerant and changes from the solid phase to the liquid phase. Change (melt). Thereby, the gas-phase refrigerant is cooled by the cold storage material 11a 'and condensed. The liquid refrigerant drops by gravity and is stored in the liquid refrigerant tank 10a.
[0135]
Then, the amount of the liquid refrigerant in the liquid refrigerant tank portion 10a decreases due to the phase change of the cold storage material 11a 'to the liquid phase, but while the liquid refrigerant in the liquid refrigerant tank portion 10a remains. Thus, the cooling operation in the vehicle compartment when the vehicle is stopped (when the compressor is stopped) can be continued.
[0136]
In addition, since the stop time due to signal waiting is usually a short time of about 1 to 2 minutes, by using about 420 g of paraffin having a freezing point of 6 ° C. and a latent heat of freezing of 229 kJ / kg as the cold storage material 11 a ′, It has been confirmed that the vehicle cabin cooling operation can be continued during a stop of about 2 minutes.
[0137]
Next, the operation and effect of the first embodiment will be described.
[0138]
(1) In the above-described prior art (Japanese Patent Laid-Open No. 2000-313226), it is necessary to separately configure the cold storage heat exchanger 40 and the liquid storage tank 43 having relatively large volumes. And the electric pump 42 need to be configured separately, so that the space for mounting the vehicle increases and the mountability of the air conditioner on the vehicle deteriorates. However, in the first embodiment, the cold storage heat exchanger 11 is connected to the evaporator 8. A refrigerant circuit configuration is connected in series to the inlet side, and a cold storage heat exchanger 11 is arranged inside the tank member 10, and a liquid refrigerant tank portion 10 a is integrally formed below the tank member 10, and an expansion valve 7 outlet is provided. Is exchanged with the cold storage heat exchanger 11 and then introduced into the evaporator 8.
[0139]
Moreover, according to the first embodiment, it is not necessary to set a special branch pipe such as the three-way branch pipe 44 of the related art between the electric pump 15 and the liquid refrigerant tank unit 10a. It can be arranged so as to be directly immersed in the liquid refrigerant in the liquid refrigerant tank portion 10a below the member 10.
[0140]
As described above, the portions corresponding to the cold storage heat exchanger 40, the liquid storage tank 43, and the electric pump 42 of the related art can be integrated into one tank member 10. Thereby, the cold storage unit 9 for the cold storage and the cooling / cooling cooling function can be configured to be extremely compact. Therefore, it is only necessary to add this single compact regenerative unit 9 to a general refrigeration cycle for air conditioning of a vehicle, and the mountability of the air conditioner on the vehicle can be greatly improved as compared with the prior art.
[0141]
(2) In the cooling / cooling mode when the vehicle is stopped, a refrigerant inflow portion that allows the refrigerant from the outlet of the evaporator 8 to flow into the tank member 10, that is, a refrigerant return pipe 16 is provided above the cold storage heat exchanger 11. Since the electric pump 15 and the liquid refrigerant tank 10a are arranged below the heat exchanger 11, the liquid refrigerant condensed in the cold storage heat exchanger 11 can quickly fall into the liquid refrigerant tank 10a by gravity.
[0142]
Therefore, the liquid refrigerant does not stagnate on the surface of the cold storage material container 11a of the cold storage heat exchanger 11. As a result, a heat transfer area where the gas-phase refrigerant and the cold storage material container 11a are in direct contact with each other in the cold storage heat exchanger 11 can always be secured.
[0143]
Thereby, the heat exchange between the gas-phase refrigerant and the cold storage material container 11a can be efficiently performed in the cooling / cooling mode, so that the condensing ability of the gas-phase refrigerant in the cold-storage heat exchanger 11 can always be kept good. Therefore, in the cooling / cooling mode, the flow rate of the liquid refrigerant to be supplied to the evaporator 8 can be sufficiently ensured, and the cooling / cooling capacity can be sufficiently exhibited.
[0144]
Further, as described above, since the cold storage heat exchanger 11 is disposed above the liquid refrigerant tank portion 10a in the tank member 10, stagnation of the liquid refrigerant on the surface of the cold storage heat exchanger 11 can be prevented. There is no need to dispose the heat exchanger 11 itself above the air-conditioning indoor unit 20 containing the evaporator 8, which is very advantageous in terms of mounting on a vehicle and increasing the degree of freedom of arrangement layout.
[0145]
(3) The electric pump 15 and the liquid refrigerant tank 10a are arranged below the cold storage heat exchanger 11 in the tank member 10, and the electric pump 15 is immersed directly in the liquid refrigerant in the liquid refrigerant tank 10a. Because of the arrangement, no matter when the vehicle stops, the electric pump 15 can suck and discharge the liquid refrigerant immediately after the start of the cooling mode, immediately after driving. Therefore, in the cooling mode, the malfunction that the electric pump 15 sucks the gas refrigerant and the supply flow rate of the refrigerant to the evaporator 8 does not occur does not occur, and the function of the cooling / cooling is immediately exhibited immediately after the vehicle stops. it can.
[0146]
(4) In a normal cooling / cooling mode in which the vehicle is running, a refrigerant inflow portion that allows low-pressure refrigerant from the outlet of the expansion valve 7 to flow into the tank member 10, that is, an inlet pipe 12 is provided above the tank member 10; A check valve 13 is provided below the cool storage heat exchanger 11 in the tank member 10, and the refrigerant below the cool storage heat exchanger 11 is introduced to the inlet side of the evaporator 8 through the check valve 13 and the outlet pipe 14. I am trying to be.
[0147]
Therefore, even in the normal cooling / cooling mode, the low-pressure refrigerant flows smoothly from the upper part to the lower part of the cold storage heat exchanger 11 along the direction of gravity, and the check valve 13 and the outlet on the lower side of the cold storage heat exchanger 11 The low-pressure refrigerant can be smoothly introduced to the inlet side of the evaporator 8 through the pipe 14.
[0148]
Then, the surplus liquid refrigerant after the completion of the cold storage of the cold storage heat exchanger 11 can be smoothly dropped to the lower liquid refrigerant tank portion 10a by gravity. Further, since the maximum liquid level (maximum liquid refrigerant storage amount) of the excess liquid refrigerant accumulated in the liquid refrigerant tank portion 10a can be defined by the position of the check valve 13 below the cold storage heat exchanger 11 as described above, When the liquid level of the surplus liquid refrigerant rises to the position of the stop valve 13, thereafter, the surplus liquid refrigerant is introduced into the evaporator 8 in a gas-liquid mixed state. That is, the refrigeration cycle operates in a state equivalent to a state where the liquid refrigerant tank unit 10a does not exist.
[0149]
(5) Next, the advantage of “connecting the regenerative heat exchanger 11 to the cooling evaporator 8 in series” according to the present embodiment will be described in detail in comparison with the related art. In the above-described conventional technology (Japanese Patent Laid-Open No. 2000-313226), the cold storage heat exchanger 40 including the cold storage material 40a is provided in parallel with the cooling evaporator 8 in the air conditioning refrigeration cycle R. It is essential that the refrigerant passage 40 be opened and closed by the solenoid valve 41 in accordance with the operation state of the refrigeration cycle.
[0150]
On the other hand, according to the present embodiment, since the cold storage heat exchanger 11 is connected in series to the cooling evaporator 8, even when the cooling heat load is very high, such as when starting cooling in summer, Since the entire amount of the cycle circulation refrigerant flow passes through the cooling evaporator 8, the addition of the cold storage heat exchanger 11 does not reduce the circulation refrigerant flow to the cooling evaporator 8.
[0151]
In addition, the freezing point of the cold storage material 11a 'in the cold storage heat exchanger 11 is set to a temperature (about 6 to 8 ° C) lower than the target upper limit temperature (about 12 to 15 ° C) of the blowing air temperature during cooling as described above. Thereby, the freezing point of the cold storage material 11a 'becomes lower than the temperature of the low-pressure refrigerant under the cooling high heat load condition. Therefore, under the condition of high cooling load, the cold storage material 11a 'does not solidify due to heat exchange with the low-pressure refrigerant, and only slightly absorbs sensible heat.
[0152]
Therefore, most of the low-pressure refrigerant absorbs heat from the air blown out of the passenger compartment in the evaporator 8 and evaporates in the same manner as in a normal air conditioner having no regenerative heat exchanger 11. That is, the maximum cooling capacity of the cooling evaporator 8 under the high cooling load condition can be satisfactorily exhibited without performing a special operation for switching the refrigerant flow to the cold storage heat exchanger 11.
[0153]
As a result, the flow of the refrigerant between the normal cooling / cooling mode when the vehicle is running and the cooling / cooling mode when the vehicle is stopped is reduced by the check valves 13 and 18 which are significantly lower in cost and smaller than the solenoid valves. You can switch.
[0154]
(6) When the solidification of the cold storage material 11a 'in the cold storage heat exchanger 11 is completed and the cold storage is completed, heat absorption of the low-pressure refrigerant in the cold storage heat exchanger 11 is almost eliminated, but the cold storage heat exchanger 11 is used for cooling. Since it is arranged on the inlet side of the evaporator 8, the expansion valve 7 can detect the degree of superheat of the refrigerant at the outlet of the evaporator 8 and adjust the flow rate of the refrigerant. Therefore, even after the completion of the cold storage, an appropriate refrigerant flow rate according to the cooling heat load of the evaporator 8 can be supplied to the evaporator 8.
[0155]
In the first embodiment, if the regenerator heat exchanger 11 is disposed on the outlet side of the evaporator 8, the evaporator 8 may have a superheat degree even if the outlet refrigerant of the evaporator 8 has a degree of superheat when the regenerative material 11a 'has been completely stored. The outlet refrigerant of No. 8 is cooled by the cold storage material 11 a ′ and the degree of superheat is reduced. As a result, the opening degree of the expansion valve 7 is reduced, and the flow rate of the refrigerant becomes too small with respect to the cooling heat load of the evaporator 8. However, such a problem does not occur by arranging the cold storage heat exchanger 11 on the inlet side of the cooling evaporator 8.
[0156]
(2nd Embodiment)
In the first embodiment, the refrigeration cycle in which the expansion valve 7 is used as the pressure reducing means and the degree of superheat of the refrigerant at the outlet of the evaporator 8 is adjusted by the expansion valve 7 has been described. An accumulator is arranged on the side (the suction side of the compressor 1), in which the gas-liquid of the evaporator outlet refrigerant is separated, the liquid refrigerant is collected, and the gas-phase refrigerant is sucked into the compressor 1 in the accumulator. And a regenerative heat exchanger 11.
[0157]
FIGS. 7 to 10 show a second embodiment, which correspond to FIGS. 1, 2, 5 and 6 described above, and the same parts as those in the first embodiment are denoted by the same reference numerals. Description is omitted. Further, since the electric control units such as the control devices 5 and 37 are the same as those of the first embodiment, the electric control units are not shown in FIGS. 7 to 10.
[0158]
In the accumulator-type refrigeration cycle, a tank-shaped accumulator is arranged on the outlet side of the evaporator 8, so that in the second embodiment, the regenerator unit 9 is formed integrally with the accumulator, focusing on this accumulator.
[0159]
That is, in the second embodiment, as shown in FIG. 8, an inlet pipe 120 for receiving the refrigerant from the outlet of the evaporator 8 is provided on the upper surface of the tank member 10 of the cool storage unit 9. The outlet refrigerant flows into the upper part in the tank member 10. Therefore, the inlet pipe 120 constitutes an inlet portion of the evaporator outlet refrigerant.
[0160]
On the other hand, a liquid refrigerant tank portion 10a for storing the liquid refrigerant is formed integrally with a lower portion of the tank member 10. The cold storage heat exchanger 11 is the same as that of the first embodiment, and is arranged at the upper part in the tank member 10, and the refrigerant flowing from the inlet pipe 120 passes through many gaps between the cold storage material containers 11 a and goes downward. Flows to
[0161]
Inside the tank member 10, first and second two outlet pipes 141 and 142 are arranged. The first outlet pipe 141 is equivalent to an outlet pipe in a normal accumulator. Therefore, the first outlet pipe 141 is formed in a U-shape, and an oil return hole 141a is opened in a U-shaped bottom portion. The oil for compressor lubrication contained in the liquid refrigerant is sucked through the hole 141a.
[0162]
Further, a gaseous-phase refrigerant suction port 141b is provided at one end of the U-shape of the first outlet pipe 141, and the gas-phase refrigerant suction port 141b is located above the liquid refrigerant stored in the lower liquid refrigerant tank 10a in the tank member 10. Open to space. Thereby, the upper gas-phase refrigerant in the tank member 10 is sucked into the first outlet pipe 141 from the gas-phase refrigerant suction port 141b. The other end of the first outlet pipe 141 is taken out of the tank from the upper surface of the tank member 10 and connected to the suction side of the compressor 1.
[0163]
In the first outlet pipe 141, a desiccant unit 141c containing a desiccant that absorbs moisture in the refrigerant is disposed downstream (downward) of the gas-phase refrigerant suction port 141b.
[0164]
On the other hand, the second outlet pipe 142 constitutes an outlet passage portion of the refrigerant circulation circuit in the cooling / cooling mode when the vehicle is stopped, and has a lower end located in the liquid refrigerant in the liquid refrigerant tank 10a. An electric pump 15 serving as a pump means for circulating the liquid refrigerant is provided at a lower end of the outlet pipe 142, and the liquid refrigerant is sucked from a suction port 15 a at a lower end of the electric pump 15 and discharged to the second outlet pipe 142. The electric pump 15 is disposed so as to be immersed in the liquid refrigerant in the liquid refrigerant tank portion 10a in this embodiment as well.
[0165]
The other end of the second outlet pipe 142 is also taken out of the tank from the upper surface of the tank member 10, and the check valve 18 is arranged in a portion of the second outlet pipe 142 above the upper surface of the tank member 10. . Thus, the other end of the second outlet pipe 142 is connected to the inlet pipe 143 of the evaporator 8 via the check valve 18. This inlet pipe 143 is a pipe that connects between the outlet side of the pressure reducing device 70 and the inlet side of the evaporator 8.
[0166]
The check valve 18 is similar to the second check valve 18 in FIG. 2. When the refrigerant pressure acts on the valve body 18a in the direction from the inlet 18b to the outlet 18c, the valve body 18a is moved to the valve seat 18d. And the valve is opened. FIG. 8 shows the open state of the check valve 18. Conversely, when the refrigerant pressure acts on the valve element 18a in the direction from the outlet 18c to the inlet 18b, the valve element 18a is pressed against the valve seat 18d and is closed.
[0167]
The second outlet pipe 142 is provided with a plate member 142a between the upper side of the gas phase refrigerant suction port 141b of the first outlet pipe 141 and the lower side of the cold storage heat exchanger 11, and the plate member 142a The refrigerant flow is prevented from colliding from above with the liquid refrigerant liquid surface around the suction port 141b. Accordingly, it is possible to prevent the refrigerant liquid surface from waving due to the refrigerant flow collision, and to surely return the gas-phase refrigerant after gas-liquid separation to the compressor suction side.
[0168]
The second embodiment relates to an accumulator-type refrigeration cycle, and separates gas-liquid of evaporator outlet refrigerant by a tank member 10 also serving as an accumulator tank, and stores the liquid refrigerant. Then, the gas-phase refrigerant can be sucked from the gas-phase refrigerant suction port 141 b of the first outlet pipe 141 and sent to the suction side of the compressor 1.
[0169]
Therefore, the liquid refrigerant can be prevented from being compressed by the compressor 1 without adjusting the degree of superheat of the refrigerant at the evaporator outlet. In the second embodiment, the pressure reducing device 70 is a fixed throttle such as a capillary tube or an orifice, or a high-pressure refrigerant pressure. A variable diaphragm or the like which responds to the above can be used. These decompression devices 70 have a simpler configuration and are less expensive than the thermal expansion valve 7 having a superheat control mechanism.
[0170]
FIG. 9 shows a normal cooling / cold storage mode during vehicle running according to the second embodiment. When the compressor 1 is driven by the vehicle engine 4, the circuit shown by the arrow in FIG. → condenser 6 → decompression device 70 → inlet pipe 143 → evaporator 8 → inlet pipe 120 → regenerative heat exchanger 11 → first outlet pipe 141 → refrigerant circulates in the circuit leading to the suction side of compressor 1 and evaporates The low-pressure refrigerant absorbs heat from the air blown in the air conditioning case 21 and evaporates in the air cooler 8, so that the air blown is cooled and the vehicle compartment can be cooled.
[0171]
Further, in the cold storage heat exchanger 11, the cold storage material 11a 'is cooled by the low-pressure refrigerant and solidified to cool the cold storage material 11a'. In the normal cooling / cool storage mode, the electric pump 15 is stopped as in the first embodiment, and the check valve 18 is closed.
[0172]
FIG. 10 shows a cooling / cooling mode when the vehicle is stopped according to the second embodiment. At this time, the electric pump 15 is operated, and the refrigerant is circulated by the circuit indicated by the arrow in FIG. That is, the electric pump 15 sucks and discharges the liquid refrigerant in the liquid refrigerant tank portion 10a below the tank member 10, and thereby the electric pump 15 → the second outlet pipe 142 → the check valve 18 (opened state) → the inlet. The refrigerant circulates in a circuit that goes from the pipe 143, the evaporator 8, the inlet pipe 120, the cold storage heat exchanger 11, and the liquid refrigerant tank 10a.
[0173]
Thus, the stored liquid refrigerant in the liquid refrigerant tank unit 10a is circulated to the evaporator 8, and the vapor-phase refrigerant evaporated in the evaporator 8 is cooled and liquefied by the cold storage heat exchanger 11, thereby providing the same as in the first embodiment. In addition, also in the second embodiment, the cooling / cooling function at the time of stopping can be satisfactorily exhibited.
[0174]
By the way, also in the second embodiment, since the cold storage heat exchanger 11 and the electric pump 15 are integrated in the tank member 10 integrally formed with the liquid refrigerant tank portion 10a, the cold storage unit 9 is formed similarly to the first embodiment. Of the vehicle can be improved (the operation and effect (1) described above).
[0175]
Further, in the second embodiment, the cold storage heat exchanger 11 is disposed in the upper part of the tank member 10, and the electric pump 15 and the liquid refrigerant tank 10 a are disposed below the cold storage heat exchanger 11. The arrangement of the inlet pipe 120 serving as the refrigerant inflow section from the upper part of the tank member 10 is the same as that of the first embodiment. Therefore, the second embodiment also includes the above-described (2) to (2) of the first embodiment. The effect of 5) can be similarly exhibited.
[0176]
By the way, since the second embodiment is an accumulator type refrigeration cycle, the regenerative heat exchanger 11 is connected in series to the outlet side of the evaporator 8. This is for the following reason. That is, in the accumulator-type refrigeration cycle, the pressure reducing device 70 can be configured by a fixed throttle such as a capillary tube or an orifice, or a variable throttle that responds to the high-pressure refrigerant pressure, and the expansion valve 7 does not need to be used. Therefore, even if the cold storage heat exchanger 11 is connected in series to the outlet side of the evaporator 8, the above-described problem of the superheat degree adjustment of the evaporator outlet refrigerant does not occur.
[0177]
Since a pressure loss always occurs in the refrigerant flow flowing through the refrigerant passage of the evaporator 8, the refrigerant pressure (evaporation pressure) at the outlet side of the evaporator 8 is lower than that at the inlet side. Here, in the accumulator type refrigeration cycle, since the gas-liquid interface of the refrigerant is formed inside the accumulator portion, in this embodiment, the tank member 10 and the refrigerant is saturated, the refrigerant in the evaporator 8 is overheated. No. Therefore, the refrigerant temperature (evaporation temperature) at the outlet side of the evaporator 8 is always lower than that at the inlet side with a decrease in the refrigerant pressure.
[0178]
As a result, in the accumulator type refrigeration cycle, the cold storage material 11a 'can be cooled by a lower temperature refrigerant by connecting the cold storage heat exchanger 11 in series at the outlet side of the evaporator 8, and the cold storage material 11a' and the refrigerant , The heat exchange efficiency can be improved, and the solidification of the cold storage material 11a 'can be completed in a shorter time.
[0179]
(Modification of First and Second Embodiments)
In the second embodiment, as shown in FIG. 8, a first outlet pipe 141 formed in a U-shape is disposed in a tank member 10 of the cold storage unit 9 and one end of the first outlet pipe 141 is connected to the tank member 10. The first outlet pipe 141 may be taken out from the bottom of the tank member 10 as shown by a two-dot chain line in FIG.
[0180]
In the second embodiment, the check valve 18 is closed when the electric pump 15 is stopped, that is, in the normal cooling / cool storage mode, so that the low-pressure refrigerant flows from the inlet pipe 143 of the evaporator 8 to the second outlet pipe 142. If the reverse flow of the low-pressure refrigerant can be reduced to a level having no practical problem by the flow resistance of the electric pump 15 itself at the time of stoppage, the check valve 18 is eliminated. Is also good.
[0181]
Further, in the first embodiment, the liquid refrigerant tank portion 10a is formed by making the sectional area of the lower part of the tank member 10 smaller than that of the upper part of the tank member 10. Further, in the second embodiment, the liquid refrigerant tank portion 10a is formed such that the cross-sectional area of the lower portion of the tank member 10 is the same as the cross-sectional area of the upper portion of the tank member 10.
[0182]
However, when it is desired to reduce the height of the liquid refrigerant tank portion 10a due to, for example, mounting on a vehicle, the cross-sectional area of the lower portion of the tank member 10 is made larger than that of the upper portion of the tank member 10 to increase the liquid refrigerant tank portion 10a. The liquid refrigerant tank portion 10a may be required to have a required volume by making the shape larger in the horizontal direction than the upper portion of the tank member 10.
[0183]
In the first and second embodiments, the electric pump 15 is disposed inside the liquid refrigerant tank 10a as shown in FIGS. 2 and 8. The electric pump 15 may be arranged at a portion outside the tank among the outlet pipes 14 and 142 taken out to the outside of the tank. In this case, if the outlet pipes 14 and 142 are taken out below the liquid refrigerant tank portion 10a and the electric pump 15 is arranged below the liquid refrigerant tank portion 10a, the suction side of the electric pump 15 is filled with liquid refrigerant. , The electric pump 15 can be started.
[0184]
(Third embodiment)
In the first embodiment, as shown in FIG. 2, a first check valve 13 is disposed below the cold storage heat exchanger 11 inside the tank member 10, and the first check valve 13 is provided in the normal cooling / cool storage mode when the vehicle is running. The refrigerant on the lower side of the cold storage heat exchanger 11 is sucked from the inlet 13 b of the stop valve 13, and the sucked refrigerant is introduced to the inlet side of the evaporator 8. For this reason, the liquid level of the stored liquid refrigerant in the liquid refrigerant tank portion 10a does not rise above the set height of the first check valve 13 as described above. Therefore, in the first embodiment, it is necessary to form the liquid refrigerant tank portion 10a having a volume required to store the liquid refrigerant amount required for the cooling / cooling mode when the vehicle is stopped below the cold storage heat exchanger 11. Occurs. This is a major obstacle to downsizing the tank member 10.
[0185]
Therefore, in the third embodiment, even if the volume of the liquid refrigerant tank portion 10a is the same, the size of the tank member 10 can be reduced as compared with the first embodiment.
[0186]
FIG. 11 shows a third embodiment, and the same parts as those in FIG. 2 (first embodiment) are denoted by the same reference numerals, and description thereof will be omitted. Hereinafter, differences from the first embodiment will be described. A pump housing portion 10b projecting downward in a cylindrical shape is formed at the center of the bottom surface of the tank member 10, and the electric pump 15 is housed and fixed in the pump housing portion 10b.
[0187]
A coolant passage 10c is formed at a predetermined interval between the inner peripheral surface of the pump housing 10b and the outer peripheral surface of the electric pump 15 so that the liquid refrigerant flows into the liquid reservoir 10d at the bottom of the pump housing 10b. Has become. The suction port 15a of the electric pump 15 is arranged at the bottom of the pump so that the liquid refrigerant in the liquid reservoir 10d is sucked. The discharge port 15b of the electric pump 15 is arranged on the upper surface of the pump and connected to the lower end of the outlet pipe 14.
[0188]
The cold storage heat exchanger 11 has a configuration in which a large number of cylindrical (stick) -type cold storage material containers 11a shown in FIG. 3A are arranged in the up-down direction. The installation location of the cold storage heat exchanger 11 is lowered to a location close to the bottom of the tank member 10. Specifically, the installation location of the cool storage heat exchanger 11 is lowered so that only a minute interval h of, for example, about 4 mm is set between the lower end of the cool storage heat exchanger 11 and the bottom surface of the tank member 10. ing. A liquid storage space 10e is formed below the cool storage heat exchanger 11 by the minute interval h.
[0189]
Further, the connection port 14 a of the outlet pipe 14 and the first check valve 13 are arranged at an intermediate portion in the vertical direction of the cold storage heat exchanger 11. A partition member 110 is provided at the center of the cold storage heat exchanger 11 to partition the periphery of the connection port 14a of the outlet pipe 14 and the first check valve 13 from the space above the cold storage heat exchanger 11.
[0190]
The partition member 110 has a disc-shaped top cover 111 and a cylindrical portion 112 located below the top cover 111, and the first check valve 13 is arranged inside the cylindrical portion 112, The outlet pipe 14 is arranged to penetrate the top cover 111 and extend in the up-down direction. Since the lower end of the cylindrical portion 112 forms an opening 113, the inlet 13 b of the first check valve 13 communicates only with the liquid storage space 10 e through the opening 113, and communicates with the space above the cold storage heat exchanger 11. Does not communicate.
[0191]
According to the third embodiment, since the inlet 13b of the first check valve 13 is arranged at an intermediate portion in the vertical direction of the cold storage heat exchanger 11, the inlet 13b is located in the tank member 10 in the normal cooling / cool storage mode when the vehicle is running. The liquid level L of the stored liquid refrigerant can rise to a level near the inlet 13b of the first check valve 13. As a result, a liquid refrigerant storage area is formed in the tank member 10 to a vertically intermediate portion of the cold storage heat exchanger 11.
[0192]
Therefore, in the third embodiment, not only the liquid storage space 10e near the inner bottom surface of the tank member 10 but also the space between the plurality of cold storage material containers 11a of the cold storage heat exchanger 11 is used for the liquid refrigerant tank portion. 10a can be configured. As a result, even if the volume of the liquid refrigerant tank portion 10a is the same, the height of the tank member 10 of the third embodiment can be significantly reduced as compared with the first embodiment of FIG. Can be downsized. Thereby, the mountability of the cold storage unit 9 on the vehicle can be improved.
[0193]
By the way, according to the third embodiment, since the liquid refrigerant tank portion 10a is also configured by utilizing the space between the multiple cold storage material containers 11a of the cold storage heat exchanger 11, the lower portion of the cold storage material container 11a is Since it will be immersed in liquid refrigerant, there is a concern that the cold storage capacity when the vehicle is running and the cooling capacity when the vehicle is stopped may be reduced. it can.
[0194]
First, regarding the cold storage capacity, the connection port 14a of the outlet pipe 14 and the periphery of the first check valve 13 are partitioned by the partition member 110, and the inlet 13b of the first check valve 13 is opened at the lower end of the partition member 110 at the opening 113. Thus, only the reservoir space 10e is communicated, and the inlet 13b is prevented from communicating with the space above the cold storage heat exchanger 11.
[0195]
For this reason, at the time of cold storage during running of the vehicle, the low-temperature and low-pressure refrigerant depressurized by the valve portion 7 a of the expansion valve 7 flows into the tank member 10 from the inlet pipe 12, and the inflow refrigerant is directly transferred to the first check valve 13. The partition member 110 prevents the entrance 13b from going toward the entrance 13b.
[0196]
As a result, the inflow refrigerant flows downward from the upper surface of the cold storage heat exchanger 11 through the gaps between the multiple cold storage material containers 11 a in the tank member 10, and the liquid storage space 10 e near the bottom surface inside the tank member 10. After that, the refrigerant passes through the opening 113 and is sucked into the inlet 13 b of the first check valve 13.
[0197]
Thus, at the time of cold storage, the refrigerant flowing into the tank member 10 always flows downward through the gap between the cold storage material containers 11a to flow the liquid refrigerant in contact with the surface of the lower portion of the cold storage material container 11a. And stir. Thereby, even if the lower part of the cool storage material container 11a is immersed in the liquid refrigerant area, the decrease in the heat transfer coefficient on the surface of the lower part of the cool storage material container 11a can be suppressed to a level that hardly causes a problem. , Necessary cold storage capacity can be secured.
[0198]
Next, the cooling capacity will be described. When cooling is stopped when the vehicle is stopped, the electric pump 15 is operated to suck the stored liquid refrigerant in the liquid reservoir 10 d and introduce it into the evaporator 8. The phase refrigerant is returned to the cold storage heat exchanger 11, and the gas refrigerant is cooled and condensed in the cold storage heat exchanger 11. Here, the condensed amount of the gas-phase refrigerant in the cool storage heat exchanger 11 can be obtained from the heat exchanger specifications such as the heat transfer area in the cool storage heat exchanger 11 and the physical properties such as the melting point of the cool storage material 11a '.
[0199]
By setting the discharge capacity of the electric pump 15 so that the amount of circulation of the liquid refrigerant by the electric pump 15 is larger than the amount of condensation of the gas-phase refrigerant, the liquid level L of the liquid refrigerant at the time of cooling is stored. 11 can be lowered below the lower end. Thereby, the gas-phase refrigerant refluxed from the outlet of the evaporator 8 can be efficiently cooled and condensed over the entire surface of the cold storage material container 11a of the cold storage heat exchanger 11, so that a decrease in cooling capacity can be prevented.
[0200]
(Fourth embodiment)
In the third embodiment, the connection port 14a of the outlet pipe 14 and the first check valve 13 are arranged at the center of the regenerative heat exchanger 11 at an intermediate position in the vertical direction of the regenerative heat exchanger 11. In the fourth embodiment, as shown in FIG. 12, the connection port 14a of the outlet pipe 14 and the first check valve 13 are arranged in the liquid storage space 10e below the cool storage heat exchanger 11.
[0201]
On the other hand, an inlet pipe 13f is connected to an inlet 13b of the first check valve 13, and a distal end side of the inlet pipe 13f is inserted into a cylindrical partition member 110, and a distal end opening 13g of the inlet pipe 13f is formed into a cylindrical shape. It is arranged in the partition member 110 at a vertically intermediate portion of the cold storage heat exchanger 11.
[0202]
Thus, in the fourth embodiment, even if the first check valve 13 is disposed in the liquid storage space 10e below the regenerative heat exchanger 11, the liquid level L of the liquid refrigerant is maintained at the front end opening 13g of the inlet pipe 13f. It can be raised to a position, that is, an intermediate portion in the vertical direction of the cold storage heat exchanger 11. Therefore, similarly to the third embodiment, the liquid refrigerant tank portion 10a can be configured by utilizing the space between the multiple cold storage material containers 11a of the cold storage heat exchanger 11. As a result, also in the fourth embodiment, the volume of the liquid storage space 10e below the cool storage heat exchanger 11 can be significantly reduced as compared with the first embodiment in FIG. 2, and the tank member 10 can be downsized.
[0203]
Further, in comparison with the third embodiment, in the fourth embodiment, since the volume of the cylindrical partition member 110 can be significantly reduced, the volume of the cold storage heat exchanger 11 is increased by that much, and the amount of the cold storage material charged is reduced. Increase can be achieved.
[0204]
In the third and fourth embodiments, an example has been described in which the cold storage material container 11a of the cold storage heat exchanger 11 is formed of a cylindrical type shown in FIG. May be constituted by a ball type shown in FIG. 3 (b) or a capsule type shown in FIG. 3 (c).
[0205]
(Fifth embodiment)
FIG. 13 shows a fifth embodiment, in which the cold storage material container 11a of the cold storage heat exchanger 11 is formed of a ball type shown in FIG. 3 (b), and the ball type cold storage material container 11a is connected to a first check valve. 13, the outlet pipe 14 and the electric pump 15 are directly and densely arranged in the surrounding space. That is, a large number of ball-type cold storage material containers 11a are laid in the surrounding space so that the spherical surfaces thereof are in close contact with each other. Therefore, a refrigerant flow path composed of minute voids is formed in a labyrinth between the spherical surfaces of the many ball-type cold storage material containers 11a.
[0206]
A minute space h is set between the lower end of the cool storage heat exchanger 11 and the bottom of the case 10 to form a liquid storage space 10e. The electric pump 15 sucks the liquid refrigerant in the liquid storage space 10e.
[0207]
In the fifth embodiment, the partition member 110 in the third and fourth embodiments is omitted. However, since the open end 12a of the inlet pipe 12 is directed to the opposite direction to the inlet 13b of the first check valve 13, that is, to the right in the example of FIG. It flows out in the direction opposite to the inlet 13b of the stop valve 13. Moreover, a number of ball-type cold storage material containers 11a are densely spread around the first check valve 13, and a refrigerant flow path formed of a minute gap is formed between the many spherical surfaces of the plurality of cold storage material containers 11a in a maze shape. Therefore, the low-pressure refrigerant flowing out of the opening end 12a of the inlet pipe 12 during the cold storage during running of the vehicle passes through the labyrinth-shaped refrigerant flow passage between the cold storage material containers 11a, and then the first check valve 13 flows toward the inlet 13b.
[0208]
From the above, even if the partition member 110 is abolished, the low-pressure refrigerant flowing out of the inlet pipe 12 does not immediately flow toward the inlet 13b of the first check valve 13, and the inlet 13b of the first check valve 13 does not flow. Since the low-pressure refrigerant passes through the labyrinth-shaped refrigerant flow path between the cold storage material containers 11a from a portion away from the low-temperature refrigerant, the low-pressure refrigerant passes through the refrigerant flow path between the cold storage material containers 11a in the cold storage heat exchanger 11, which is quite wide. . As a result, even if the lower part of the cold storage material container 11a is immersed in the liquid refrigerant area, and the partition member 110 is abolished, the decrease in the cold storage capacity with respect to the third and fourth embodiments is slightly reduced. Can be suppressed.
[0209]
In addition, the discharge capacity of the electric pump 15 is set such that the amount of circulation of the liquid refrigerant by the electric pump 15 is larger than the amount of condensation of the gas-phase refrigerant at the time of cooling as in the third and fourth embodiments. The same cooling ability as that of the fourth embodiment can be secured.
[0210]
According to the fifth embodiment, the first check valve 13 is arranged inside the cold storage heat exchanger 11, and the electric pump 15 is also configured so that most of the electric pump 15 is arranged inside the cold storage heat exchanger 11. The tank member 10 can be further reduced in size than the third and fourth embodiments. In particular, the effect of reducing the overall height of the tank member 10 is great.
[0211]
Further, since the partition member 110 is abolished and a large number of ball-type cold storage material containers 11a are directly and densely spread around the first check valve 13, the volume of the cold storage material charged by the partition space of the partition member 110 is reduced. Does not occur, and the amount of cold storage material can be increased.
[0212]
(Sixth embodiment)
The sixth embodiment relates to the miniaturization of the cool storage heat exchanger 11 which occupies most of the physical size of the cool storage unit 9. The cold storage heat exchanger 11 needs a large heat transfer area corresponding to the cold storage and cooling capacity in order to exhibit the predetermined cooling and cooling capacity. If it is attempted to increase the regenerative storage capacity by increasing the regenerative material filling amount while securing the heat transfer area, the regenerative heat exchanger 11 inevitably increases in size and the heat exchanger weight increases, and the regenerator unit 9 Of the vehicle is deteriorated.
[0213]
Therefore, in the sixth embodiment, the size of the cool storage heat exchanger 11 is reduced by devising the heat transfer configuration of the cool storage heat exchanger 11. 14 and 15 show a specific example of the cool storage heat exchanger 11 according to the sixth embodiment, and FIG. 16 shows an example in which the cool storage heat exchanger 11 according to the sixth embodiment is incorporated in the cool storage unit 9. FIG. 16 shows the regenerator unit 9 applied to the expansion valve cycle shown in FIG. 1, that is, the refrigeration cycle R in which the expansion valve 7 is used as the pressure reducing means to control the superheat degree of the evaporator outlet refrigerant.
[0214]
The regenerative heat exchanger 11 according to the sixth embodiment is based on a heat exchanger configuration generally called a shell and tube type. That is, the cool storage heat exchanger 11 is a shell 11d that is a cylindrical tank member, a tube 11e that is fixed to the shell 11d, and that constitutes a refrigerant flow path, and that is thermally integrated with the tube 11e. And fins 11f constituting an enlarged heat transfer surface.
[0215]
The shell 11d has a configuration in which an upper end and a lower end of a cylindrical main body 11g are sealed by an upper lid 11h and a lower lid 11i. As shown in FIG. 16, the outer diameter of the shell 11d is set so as to fit on the inner peripheral surface of the case member 10 of the cool storage unit 9, and the shell 11d is fixed to the inner peripheral surface of the case member 10.
[0216]
In this example, the tube 11e is a circular tube, and the fin 11f is a plate fin having a circular flat plate shape. The fin 11f has a burring hole 11j for inserting a tube. A large number of flat fins 11f are stacked at a predetermined fin pitch Pf, and after inserting the tubular tube 11e into the burring hole 11j, the tubular tube 11e is expanded to connect the fin 11f and the tube 11e. Mechanically fixed together. At the same time as the mechanical fixation, the fin 11f and the tube 11e are thermally integrated together.
[0219]
After the fin 11f and the tube 11e are fixed, the tube 11e is vertically arranged to extend vertically with respect to the shell 11d, and a combined body of a large number of the fins 11f and the tube 11e is accommodated inside the shell 11d. The upper end and lower end of 11e are assembled to the shell 11d such that they protrude upward and downward, respectively, of the shell 11d.
[0218]
In this assembly, the portions near the upper end and the lower end of the tube 11e are sealed and fixed to the upper lid 11h and the lower lid 11i of the shell 11d by joining means such as brazing, respectively.
[0219]
The tube 11e and the fin 11f are formed of a metal having good thermal conductivity, for example, aluminum. Each part 11g, 11h, 11i of the shell 11d is also formed of a metal such as aluminum.
[0220]
A cold storage material inlet 11k is provided in a part of the shell 11d having a sealed case structure, for example, the upper lid 11h, and the cold storage material 11a 'is injected into the inside of the shell 11d from the inlet 11k. In the inside of the shell 11d, the cold storage material 11a 'is filled in the gap between the flat fins 11f (gap by the fin pitch Pf). After the end of the injection of the cold storage material 11a ', the injection port 11k is sealed by the plug 11m.
[0221]
Here, since the cold storage material 11a 'is used for cold storage of a vehicle air conditioner, it is preferable that the cold storage material 11a' has a melting point of about 4 ° C. to 8 ° C. and has physical properties that do not cause supercooling. Specifically, paraffin (n-tetradecane) is preferable as satisfying such physical properties.
[0222]
By the way, since the paraffin used as the cold storage material 11a 'has a considerably smaller thermal conductivity than metal, it is necessary to increase the heat transfer area by thinning the paraffin layer in order to increase the cold storage capacity and the cooling capacity. desirable. For this purpose, the regenerative heat exchanger 11 is configured as a shell-and-tube type heat exchanger, and the minute gaps between the fins 11f (the gaps due to the fin pitch Pf) are filled with paraffin in a thin film form.
[0223]
Here, the fin pitch Pf is preferably in the range of about 0.5 to 2 mm in order to secure the heat transfer performance of the regenerative heat exchanger 11 and reduce the size thereof, as described later, and more specifically, the value in the vicinity of 1.5 mm. Set to.
[0224]
The cold storage material 11a 'undergoes a phase change with a change in the cold storage mode / cooling mode, and accordingly, the density changes and the volume changes. Due to the volume change of the cold storage material 11a ', stress is generated in the flat fin 11f, which causes metal fatigue of the cold storage heat exchanger 11.
[0225]
Therefore, as shown in FIG. 14, each fin 11f is provided with a through-hole 11n vertically penetrating a large number of laminated plate-like fins 11f. Accordingly, even when the volume of the cold storage material 11a 'increases when the cold storage material 11a' changes its phase from the solid state to the liquid phase state in the cooling mode, the liquid storage material 11a 'in the liquid phase between the fins has a through hole. 11n can be smoothly moved to the outside of the fin.
[0226]
Although FIG. 14 illustrates an example in which only one through hole 11n is provided at the center of the plate fin 11f having a circular flat plate shape, actually, the smooth movement of the liquid-phase cold storage material 11a 'is performed. For this purpose, it is preferable to provide a plurality of through holes 11n at predetermined intervals.
[0227]
Further, between the inner peripheral surface of the cylindrical main body 11g of the shell 11d and the outer peripheral end of the flat fin 11f, a gap 11p for heat insulation having a predetermined interval B (for example, about 2 mm) is provided. The gap 11p is for ensuring the heat insulating effect of the cold storage heat of the cold storage material 11a 'even when the cold storage unit 9 is installed in a high temperature environment (for example, an engine room) outside the vehicle compartment.
[0228]
As described above, in this example, a circular tube (round tube) is used as the tube 11e, and in order to increase the number of tubes to secure the heat transfer area on the refrigerant side, the inner diameter of the circular tube 11e is about 4 mm. The following is preferred. It should be noted that a flat tube or a flat multi-hole tube may be employed as the tube 11e. In the case of a flat tube, it is preferable that the tube has an equivalent diameter of about 1 mm in inner diameter in order to secure a heat transfer area on the refrigerant side.
[0229]
Next, the function and effect of the sixth embodiment will be described. The operation of the entire cold storage unit 9 having the cold storage heat exchanger 11 according to the sixth embodiment is the same as that of the first embodiment (FIG. 2), and therefore, the description is omitted.
[0230]
In the cool storage heat exchanger 11 according to the sixth embodiment, the basic configuration of the heat exchanger is a shell-and-tube type heat exchanger configuration, and a paraffin is formed in a minute gap between the flat fins 11f (gap by the fin pitch Pf). Is a first feature of the present invention, and the first feature is devised based on the following study.
[0231]
The present inventor first assumed that the form of the heat transfer partition when latent heat is stored in the cold storage material 11a 'is based on the premise that the cold storage heat exchanger 11 is used for cooling and cooling when the vehicle is stopped. A comparison was made to determine which of the one-dimensional surface configuration, the two-dimensional surface configuration, and the three-dimensional surface configuration is most advantageous for miniaturization.
[0232]
Therefore, as typical examples of the heat transfer partitions (1) to (3), (1) flat / laminated type (parallel plate type) and (2) cylindrical type (type of FIG. 3 (a)) shown in FIG. , (3) The ball type (type of FIG. 3 (b)) is taken up, and the three types of heat transfer bulkheads (1) to (3) have the same cold storage and cooling under the same cold storage material weight (600 g). The heat transfer area for each shape where the ability was obtained was calculated by computer simulation and compared. The heat transfer area in FIG. 17 shows the calculation result by this computer simulation.
[0233]
In the calculation example of FIG. 17, paraffin (n-tetradecane having a melting point of 5.9 ° C.) is used as a cold storage material, and the heat transfer partition walls of each shape are made of an aluminum alloy material having a thickness of 0.3 mm. You are using
[0234]
In FIG. 17, (1) a flat / laminated type (parallel plate type) heat transfer partition can be constituted by a parallel plate type plate fin f11 in the shell and tube type cold storage heat exchanger 11 according to the sixth embodiment. Therefore, the dimension d in (1) in FIG. 17 is a value obtained by subtracting the plate thickness (0.3 mm) of the plate fin f11 from the fin pitch Pf in FIG.
[0235]
As is clear from the comparison of the heat transfer areas of the heat transfer partitions having the respective shapes shown in FIG. 17, the heat transfer areas required for exhibiting the same cold storage and cooling capacity are defined as (1) a plane / laminated type (parallel plate). It can be seen that the size can be minimized by the (type) heat transfer partition. That is, it can be seen that the flat / laminated type heat transfer partition is most advantageous for downsizing the heat exchanger.
[0236]
This is for the following reason. In other words, it is advantageous to reduce the thickness of the cold storage material when performing cold storage by phase change. However, when the heat transfer areas of the above three types of heat transfer partitions are the same, a cylindrical type (2) is considered. The thickness of the cold storage material (corresponding to the inner diameter d in FIG. 17) is twice as large as that of the flat / laminated type (1), and the thickness of the cold storage material (corresponding to the inner diameter d in FIG. 17) for the ball type (3). ) Increases by three times that of the flat / laminated type (1), so the heat transfer performance is not the same, and the heat transfer performance in the order of the flat / laminated type (1) → cylindrical type (2) → ball type (3) Is to be reduced.
[0237]
From the study results in FIG. 17, it is found that the flat and laminated type (1) heat transfer partition, that is, the shell and tube type regenerative heat exchanger 11 having the flat fins 11f is configured as in the sixth embodiment. Compared to a regenerative heat exchanger having cylindrical type (2) or ball type (3) heat transfer bulkheads, the size of the heat exchanger (occupied volume in FIG. 17) can be reduced by about 10 to 25% and mounted on a vehicle. This is very advantageous for improving the performance. The unit [L] of the occupied volume in FIG. 17 indicates liter.
[0238]
In FIG. 17, the filling rate is a ratio of the total volume of the heat transfer partition and the cold storage material to the volume occupied by the cold storage heat exchanger. In the case of the cylindrical type (2) or the ball type (3), the filling rate is inevitably determined by the shape of the partition itself, but the heat transfer partition of the flat / laminated type (1) according to the sixth embodiment is used. In this case, since the filling rate is not necessarily determined by the partition shape itself, a value of 0.9 is applied in consideration of the presence of the refrigerant tube 11e.
[0239]
By the way, in the comparative study of FIG. 17, as described above, the plate thickness of each shape of the heat transfer partition is applied under the same condition, specifically, the plate thickness t = 0.3 mm. With the shell-and-tube type heat exchanger configuration, the refrigerant pressure acts only on the refrigerant tube 11e, and the refrigerant pressure does not act on the flat fin 11f forming the heat transfer partition (enlarged heat transfer surface). For this reason, the plate-shaped fin 11f does not require a plate thickness for securing the pressure resistance against the refrigerant pressure.
[0240]
Therefore, in the sixth embodiment, when the cold storage heat exchanger 11 is formed, an aluminum alloy having a high thermal conductivity is used as a metal forming the flat fins 11f. The thickness can be further reduced than the tube 11e. Specifically, the thickness of the refrigerant tube 11e is set to 0.3 mm, while the thickness of the flat fin 11f can be reduced to about 0.1 mm. Even if the thickness of the flat fin 11f is reduced to about 0.1 mm, the decrease in the fin efficiency is negligibly small.
[0241]
In each of the heat transfer partitions of Comparative Examples (2) and (3), a cold storage material container was formed, a refrigerant passage was formed on the outer surface side, and the refrigerant pressure was directly applied to the outer surface side of the heat transfer partition. Since it acts, it is difficult to reduce the thickness from the viewpoint of securing the pressure resistance.
[0242]
As described above, with the shell and tube type heat exchanger configuration of the sixth embodiment, the plate thickness of the flat fin 11f forming the heat transfer partition is set to a value smaller than the plate thickness of the tube 11e forming the refrigerant passage. Since they can be set independently, the occupied volume of the heat exchanger can actually be made smaller than the study result of FIG. 17, and the heat exchanger can be effectively reduced in size and weight.
[0243]
Next, referring to the fin pitch Pf of the flat fin 11f, the fin pitch Pf is preferably in the range of 0.5 mm to 2 mm for the following reason. That is, when the fin pitch Pf is larger than 2 mm, the heat transfer performance is deteriorated due to the increase in the thickness of the cold storage material 11a ', and further, the cold storage and cooling ability is significantly reduced. The fin pitch Pf is preferably set to 2 mm or less because the heat transfer area is increased and the heat exchanger size is increased.
[0244]
Conversely, when the fin pitch Pf is reduced, the number of fins per unit volume of the cold storage material necessarily increases, even if the heat transfer performance is sufficient. It is disadvantageous for weight reduction. For this reason, the fin pitch Pf is preferably actually 0.5 mm or more.
[0245]
By the way, according to the sixth embodiment, the tubes 11e are vertically arranged in the regenerative heat exchanger 11, and the refrigerant flows from the upper side to the lower side in the tubes 11e. Therefore, the refrigerant is cooled and condensed in the tubes 11e at the time of cooling. The liquid refrigerant quickly drops to the lower liquid refrigerant tank 10a under the influence of gravity.
[0246]
As a result, the condensed liquid film on the inner surface of the tube 11e can always be kept thin, so that the deterioration of the heat transfer performance due to the condensed liquid film during cooling can be suppressed, and the cooling performance can be effectively exhibited.
[0247]
Further, in the sixth embodiment, through holes 11n (FIG. 14) penetrating vertically through a large number of the stacked flat plate fins 11f are provided in each fin 11f, and the liquid-phase cold storage material 11a 'is passed through the through holes 11n. It is easy to move. For this reason, when the cold storage material 11a 'changes its phase from the liquid phase state to the solid state state during cold storage and the volume of the cold storage material decreases, the cold storage material 11a' in the liquid phase is transferred from the outside of the fin to the fin through the through hole 11n. Can be supplied smoothly. Therefore, the cold storage material 11a 'is efficiently cooled between the fins, and the cold storage can be completed in a short time.
[0248]
On the other hand, at the time of cooling, the volume of the cold storage material 11a 'increases as the phase of the cold storage material 11a' changes from the solid state to the liquid phase state. At this time, the cold storage material 11a 'in the liquid phase is smoothly passed through the through hole 11n. It can be pushed out from between the fins to the outside of the fins. For this reason, it is possible to prevent the fin 11f from generating an excessive stress due to the phase change (volume change) of the cold storage material 11a '. Thereby, metal fatigue at the joint between the fin 11f and the tube 11e can be prevented, and the durability of this joint can be improved.
[0249]
In the sixth embodiment, a gap 11p for heat insulation is provided between the inner peripheral surface of the cylindrical main body 11g of the shell 11d and the outer peripheral end of the flat fin 11f, so that the cold storage material 11a 'can be cooled. The heat insulation effect of heat can be exhibited effectively.
[0250]
The heat insulating effect will be described in detail. Since the cylindrical main body 11g of the shell 11d is directly fitted to the inner wall surface of the case member 10 of the cool storage unit 9 as shown in FIG. Heat penetrates into the inside of the cylindrical main body 11g through the case member 10 and the wall surface of the cylindrical main body 11g, and the temperature of the gap 11p rises.
[0251]
As a result, the temperature of the cold storage material 11a 'located in the gap 11p becomes equal to or higher than the melting point, and the cold storage material 11a' maintains a liquid phase state. Here, the thermal conductivity λ of the cold storage material 11a ′ such as paraffin, water, and the like is much smaller in the liquid state than in the solid state. For example, in the case of paraffin, the thermal conductivity in the solid phase λ = 0.28 W / mK, whereas the thermal conductivity in the liquid phase λ = 0.14 W / mK, To a half of the rate λ.
[0252]
Therefore, since the cold storage material 11a 'located in the gap portion 11p is almost always in a liquid phase state, the cold storage material 11a' can effectively exhibit the heat insulating effect due to its low thermal conductivity. Therefore, even if a large temperature difference occurs between the cylindrical main body 11g of the shell 11d and the fin 11f, the amount of heat entering from the shell 11d side can be effectively reduced.
[0253]
Therefore, even if the cool storage unit 9 is arranged in a high-temperature atmosphere where the temperature is sufficiently higher than the melting point of the cool storage material 11a ', the cooling heat loss to the outside of the cool storage unit 9 can be effectively suppressed. Thereby, the heat insulating material separately provided on the case member 10 of the cold storage unit 9 becomes unnecessary, and even when the heat insulating material is separately provided, the amount of the heat insulating material can be significantly reduced.
[0254]
As can be understood from the above description, according to the sixth embodiment, all the main components necessary for realizing cooling and cooling when the vehicle engine is stopped are housed in a common case member 10 for storing liquid. In the cold storage unit 9 composed of a cooling unit, the cold storage heat exchanger 11 occupying most of the physique can be effectively reduced in size, and the mountability of the cold storage unit 9 in a vehicle can be improved.
[0255]
(Seventh embodiment)
As shown in FIG. 16, the sixth embodiment relates to a regenerator unit 9 applied to an expansion valve cycle in which an expansion valve 7 is used as a pressure reducing means to control the degree of superheat of evaporator outlet refrigerant. The configuration of the cold storage heat exchanger according to the sixth embodiment can be similarly applied to the accumulator cycle shown in FIG. 7 (second embodiment).
[0256]
FIG. 18 shows a seventh embodiment, in which the configuration of the cold storage heat exchanger of the sixth embodiment is applied to the accumulator cycle shown in FIG. The cold storage unit 9 of the seventh embodiment shown in FIG. 18 corresponds to the cold storage unit 9 of the second embodiment shown in FIG. 8 in which the cold storage heat exchanger configuration is replaced with the cold storage heat exchanger configuration of the sixth embodiment. I do. Therefore, in FIG. 18, the same parts as those in FIGS. 8 and 16 are denoted by the same reference numerals, and the specific description of the seventh embodiment is omitted.
[0257]
(Eighth embodiment)
In the regenerative heat exchanger configuration according to the sixth embodiment, as shown in FIGS. 14 and 15, insertion holes (burring holes in the example of FIG. 14) into which a number of tubes 11e are inserted into one circular flat fin 11f. A tube 11e is inserted into each of the insertion holes 11j, and a large number of tubes 11e are integrally joined to one circular flat fin 11f at each of the insertion holes 11j. In the embodiment, as shown in FIG. 19 and FIG. 20, circular flat fins 11f divided into a plurality of tubes 11e are integrally joined.
[0258]
As in the sixth embodiment, a large number of circular plate-shaped fins 11f provided with insertion holes 11j for a large number of tubes 11e are stacked, and the tube 11e is inserted into each of the insertion holes 11j of the large number of stacked fin groups. In the joining structure to be joined, the assembling work may be difficult due to the influence of the dimensional variation of the inner diameter of the insertion hole 11j and the outer shape of the tube 11e, the variation of the hole pitch of the insertion hole 11j, and the like.
[0259]
On the other hand, in the eighth embodiment, a circular flat fin 11f is divided and formed correspondingly for each tube 11e, and a large number of fins 11f are laminated for each tube 11e. The tube 11e is inserted into the insertion hole 11j and joined. That is, the tubes 11e and the fins 11f are assembled for each tube 11e.
[0260]
Thereafter, the assembled bodies of the tubes 11e are assembled in a vertical arrangement such that the tubes 11e are oriented vertically, and the fin 11f connection portion of the assembled body is stored in the shell 11d, and The vicinity of the upper end and the lower end of 11e is sealed and fixed to the upper lid 11h (see FIG. 14) and the lower lid 11i (see FIG. 14) of the shell 11d.
[0261]
According to the eighth embodiment, since the tubes 11e and the fins 11f can be independently assembled for each tube 11e, the assembling work of the tubes 11e and the fins 11f can be performed even if there is a dimensional variation as described above. It can be done easily.
[0262]
The joining of the tube 11e and the fin 11f may be performed by means such as tube expansion or brazing as in the sixth embodiment.
[0263]
(Ninth embodiment)
In the eighth embodiment, a large number of circular flat fins 11f formed separately for each tube 11e are laminated, and the tube 11e is inserted into the insertion hole 11j of the large number of laminated fin groups and joined. In the ninth embodiment, as shown in FIG. 21, a flat fin 11f is integrally formed on the outer peripheral surface of the cylindrical tube 11e by forging.
[0264]
The plate-like fin 11f according to the ninth embodiment is integrally formed on the outer peripheral surface of the tubular tube 11e in a spiral form inclined at a small angle from a plane perpendicular to the tube longitudinal direction. For this reason, the flat fins 11f spirally continuous on the outer peripheral surface of the tubular tube 11e can be efficiently and integrally formed.
[0265]
According to the ninth embodiment, the flat fins 11f are spirally continuous, so that the flat fins 11f are arranged in parallel with the flat fins 11f as in the sixth to eighth embodiments. Although the form is different, by setting the spiral pitch Pf ′ of the flat fins 11f that are spirally continuous to the same range (0.5 to 2.0 mm) as the fin pitch Pf described above, As in the sixth to eighth embodiments, the size of the cold storage heat exchanger 11 can be reduced.
[0266]
It should be noted that the cold storage heat exchanger configurations according to the eighth and ninth embodiments can be similarly applied to both the cold storage unit 9 for the expansion valve cycle shown in FIG. 16 and the cold storage unit 9 for the accumulator cycle shown in FIG. Of course.
[0267]
(Other embodiments)
In each of the above embodiments, the vehicle air conditioner mounted on the vehicle that controls the vehicle engine 4 to stop when the vehicle is stopped has been described. However, for example, the vehicle engine 4 and the electric motor are used as power sources for driving the vehicle. The present invention may be applied to a hybrid vehicle having both of them. In a hybrid vehicle, the vehicle engine 4 may be stopped according to running conditions (for example, at the time of deceleration, low-load running, etc.) even when the vehicle is running. What is necessary is just to implement the cooling mode of embodiment.
[Brief description of the drawings]
FIG. 1 is a circuit diagram of a refrigeration cycle showing a first embodiment of the present invention.
FIG. 2 is a cross-sectional view illustrating a specific configuration of the cool storage unit of FIG.
FIG. 3 is a perspective view illustrating the cold storage material container of FIG. 2;
FIG. 4 is a schematic sectional view of an air-conditioning indoor unit according to the first embodiment.
FIG. 5 is an operation explanatory view in a normal cooling / cool storage mode according to the first embodiment;
FIG. 6 is an operation explanatory diagram in a cooling / cooling mode according to the first embodiment.
FIG. 7 is a circuit diagram of a refrigeration cycle showing a second embodiment.
FIG. 8 is a cross-sectional view illustrating a specific configuration of the cool storage unit of FIG. 7;
FIG. 9 is an operation explanatory diagram in a normal cooling / cool storage mode according to the second embodiment.
FIG. 10 is an operation explanatory diagram in a cooling / cooling mode according to the second embodiment.
FIG. 11 is a cross-sectional view illustrating a specific configuration of a cool storage unit according to a third embodiment.
FIG. 12 is a cross-sectional view illustrating a specific configuration of a cool storage unit according to a fourth embodiment.
FIG. 13 is a cross-sectional view illustrating a specific configuration of a cool storage unit according to a fifth embodiment.
FIG. 14 is a cross-sectional view illustrating a specific configuration of a cool storage heat exchanger according to a sixth embodiment.
FIG. 15 is a schematic perspective view illustrating a specific configuration of a cool storage heat exchanger according to a sixth embodiment.
FIG. 16 is a cross-sectional view illustrating a specific configuration of a cool storage unit according to a sixth embodiment.
FIG. 17 is a table illustrating a comparison of heat transfer partition specifications between a cold storage heat exchanger according to a sixth embodiment and a comparative example.
FIG. 18 is a cross-sectional view illustrating a specific configuration of a cool storage unit according to a seventh embodiment.
FIG. 19 is a schematic perspective view illustrating a specific configuration of a cool storage heat exchanger according to an eighth embodiment.
FIG. 20 is a sectional view of a main part of a cool storage heat exchanger according to an eighth embodiment.
FIG. 21 is a sectional view of a main part of a cool storage heat exchanger according to a ninth embodiment.
FIG. 22 is a circuit diagram of a refrigeration cycle of a conventional device.
[Explanation of symbols]
1 compressor, 4 vehicle engine, 6 condenser (high-pressure side heat exchanger),
7 ... expansion valve (pressure reducing means), 70 ... pressure reducing device (pressure reducing means) such as fixed throttle, etc.
8 evaporator, 9 cold storage unit, 10 tank member, 10a liquid refrigerant tank section, 11 cold storage heat exchanger, 11a cold storage material container, 15 electric pump.

Claims

A compressor (1) driven by a vehicle engine (4);
A high-pressure side heat exchanger (6) for radiating heat of the high-pressure refrigerant discharged from the compressor (1);
Decompression means (7, 70) for decompressing the refrigerant that has passed through the high-pressure side heat exchanger (6);
An evaporator (8) for evaporating the low-pressure refrigerant decompressed by the decompression means (7, 70) and cooling the air blown into the vehicle interior;
A cold storage heat exchanger (11) provided in series with the evaporator (8) and having a cold storage material (11a ') cooled by the low-pressure refrigerant when the compressor (1) is operated;
A tank member (10) integrally incorporating at least the cold storage heat exchanger (11) and a pump means (15) for circulating liquid refrigerant,
A liquid refrigerant tank portion (10a) for storing the liquid refrigerant is integrally formed below the tank member (10);
When the vehicle engine (4) stops and the compressor (1) stops, the liquid refrigerant in the liquid refrigerant tank (10a) is introduced into the evaporator (8) by the pump means (15), An air conditioner for a vehicle, wherein a gas-phase refrigerant evaporated in the evaporator (8) is introduced into the cold storage heat exchanger (11), and cooled and condensed by the cold storage heat of the cold storage material (11a '). .

The cold storage heat exchanger (11) is arranged on the upper side of the inside of the tank member (10), and the pump means (15) is arranged below the cold storage heat exchanger (11). Item 2. The vehicle air conditioner according to Item 1.

The vehicle air conditioner according to claim 2, wherein the pump means (15) is disposed so as to be immersed in the liquid refrigerant in the liquid refrigerant tank portion (10a).

An outlet passage (14) connecting the discharge side of the pump means (15) to the inlet side of the evaporator (8) is arranged inside the tank member (10);
A connection port (14a) is opened in the middle of the outlet passage section (14),
A first check valve (13) is provided at the connection port (14a) to allow the flow of the refrigerant only in one direction from the internal space of the tank member (10) into the outlet passage section 14). The vehicle air conditioner according to any one of claims 1 to 3.

When the compressor (1) is operated, the suction opening ends (13b, 13g) of the refrigerant sucked into the first check valve (13) from inside the tank member (10) are connected to the cold storage heat exchanger (11). The vehicle air conditioner according to claim 4, wherein the air conditioner is disposed above a lower end of the vehicle.

The vehicle air conditioner according to claim 5, wherein the first check valve (13) is disposed above a lower end of the cool storage heat exchanger (11).

The first check valve (13) is disposed below the cold storage heat exchanger (11), and is located between an inlet (13b) of the first check valve (13) and the suction opening end (13g). 6. The air conditioner for a vehicle according to claim 5, wherein the suction opening end (13g) is disposed higher than a lower end portion of the cold storage heat exchanger (11) by connecting the cooling storage heat exchanger (11) by a pipe (13f). apparatus.

When the compressor (1) is operated, the suction openings (13b, 13g) of the refrigerant passages (13, 14) for introducing the refrigerant sucked from inside the tank member (10) to the inlet side of the evaporator (8). The air conditioner for a vehicle according to any one of claims 1 to 3, wherein the air conditioner is disposed above a lower end of the cold storage heat exchanger (11).

During operation of the compressor (1), the refrigerant flowing into the space above the cold storage heat exchanger (11) flows from above the cold storage heat exchanger (11) to below, and the cold storage heat exchanger (11). The vehicle air conditioner according to any one of claims 5 to 8, wherein the refrigerant makes a U-turn at a lower portion of the vehicle and is drawn into the suction opening ends (13b, 13g). .

A partition member (110) for partitioning the periphery of the suction opening end (13b, 13g);
An opening (113) is formed in the partition member (110) below the cool storage heat exchanger (11), and the refrigerant in the lower part of the cool storage heat exchanger (11) is formed through the opening (113). 10. The vehicle air conditioner according to claim 9, wherein air is taken into the suction opening ends (13b, 13g).

When the vehicle engine (4) stops and the compressor (1) stops, the liquid refrigerant circulation by the pump means (15) is smaller than the amount of refrigerant condensed in the cold storage heat exchanger (11). The vehicle air conditioner according to any one of claims 5 to 10, wherein the discharge capacity of the pump means (15) is set so as to increase the flow rate.

The decompression means is an expansion valve (7) that adjusts the flow rate of the refrigerant according to the degree of superheating of the refrigerant at the outlet of the evaporator (8).
The vehicle air conditioner according to any one of claims 1 to 11, wherein the cold storage heat exchanger (11) is provided on a refrigerant inlet side of the evaporator (8).

The refrigerant inflow portion (12) from the outlet of the expansion valve (7) to the tank member (10) and the refrigerant inflow portion (16) from the outlet of the evaporator (8) to the tank member (10) are formed as described above. The air conditioner for a vehicle according to claim 12, wherein the air conditioner is disposed above the cold storage heat exchanger (11).

A second check that allows the refrigerant to flow only in one direction from the outlet of the evaporator (8) to the tank member (10) at the refrigerant inflow portion (16) from the outlet of the evaporator (8). 14. A vehicle air conditioner according to claim 13, wherein a valve (18) is arranged.

A compressor (1) driven by a vehicle engine (4);
A high-pressure side heat exchanger (6) for radiating heat of the high-pressure refrigerant discharged from the compressor (1);
Decompression means (70) for decompressing the refrigerant that has passed through the high-pressure side heat exchanger (6);
An evaporator (8) for evaporating the low-pressure refrigerant decompressed by the decompression means (70) and cooling the air blown into the vehicle interior;
A tank member (10) disposed on the refrigerant outlet side of the evaporator (8) and integrally forming a liquid refrigerant tank portion (10a) for storing liquid refrigerant at a lower portion thereof;
The gas-liquid of the low-pressure refrigerant at the outlet of the evaporator (8) is separated inside the tank member (10), and the gas-phase refrigerant is discharged to the suction side of the compressor (1), During operation of the compressor (1), a cold storage heat exchanger (11) having a cold storage material (11a ') cooled by the low-pressure refrigerant after passing through the evaporator (8), and a liquid refrigerant circulation pump means (15) ) Is integrated into at least the tank member (10),
When the vehicle engine (4) stops and the compressor (1) stops, the liquid refrigerant in the liquid refrigerant tank (10a) is introduced into the evaporator (8) by the pump means (15), An air conditioner for a vehicle, wherein a gas-phase refrigerant evaporated in the evaporator (8) is introduced into the cold storage heat exchanger (11), and cooled and condensed by the cold storage heat of the cold storage material (11a '). .

The cold storage heat exchanger (11) is arranged on the upper side of the inside of the tank member (10), and the pump means (15) is arranged below the cold storage heat exchanger (11). Item 16. The vehicle air conditioner according to item 15.

The vehicle air conditioner according to claim 16, wherein the pump means (15) is disposed so as to be immersed in the liquid refrigerant in the liquid refrigerant tank portion (10a).

18. The cooling unit according to claim 15, wherein a refrigerant inlet (120) from an outlet of the evaporator (8) to the tank member (10) is arranged above the cold storage heat exchanger (11). The vehicle air conditioner according to one of the preceding claims.

An outlet passage (142) connecting a discharge side of the pump means (15) to an inlet side of the evaporator (8);
A check valve (18) is provided in the outlet passage section (142) to allow the flow of the refrigerant only in one direction from the pump means (15) to the inlet side of the evaporator (8). The vehicle air conditioner according to any one of claims 15 to 18.

The compressor (1) driven by the vehicle engine (4) and the evaporator (8) for evaporating the low-pressure refrigerant decompressed by the decompression means (7, 70) and cooling the air blown into the vehicle interior. A cold storage heat exchanger applied to a vehicle air conditioner having a refrigeration cycle (R),
A tube (11e) through which the refrigerant of the refrigeration cycle (R) flows;
A fin (11f) thermally integrated with the tube (11e) and constituting an enlarged heat transfer surface of the tube (11e);
A shell (11d) for accommodating a combined body of the tube (11e) and the fin (11f);
The compressor (1) is accommodated in the shell (11d), and is cooled by a low-temperature refrigerant passing through the tube (11e) when the compressor (1) is operating, and cools down. A cold storage material (11a ′) that cools and condenses the gas-phase refrigerant evaporated by the cooler (8) with cold storage heat;
A cool storage heat exchanger for a vehicle air conditioner, wherein the cool storage material (11a ') is filled in a thin film shape between heat transfer surfaces of the fins (11f).

The cold storage heat exchanger according to claim 20, wherein the tubes (11e) are arranged vertically, and the refrigerant flows through the tubes (11e) from above to below.

22. The heat storage heat exchanger of a vehicle air conditioner according to claim 20, wherein the fins (11f) are flat fins arranged substantially in parallel at a predetermined fin pitch.

23. The cold storage heat exchanger according to claim 22, wherein the flat fins (11f) are formed by a plurality of fins stacked at the predetermined fin pitch.

23. The tube according to claim 22, wherein the tube (11e) has a tubular shape, and the flat fins (11f) are integrally formed in a spiral shape continuously on an outer peripheral surface of the tube (11e). The cold storage heat exchanger of the vehicle air conditioner according to the above.

The heat storage heat exchanger according to any one of claims 20 to 24, wherein the fin pitch is set in a range of 0.5 mm to 2.0 mm.

26. A vehicle air conditioner according to any one of claims 20 to 25, wherein the fin (11f) is provided with a through hole (11n) that allows movement of the cold storage material (11a ') with a change in volume. Cold storage heat exchanger of the device.

The heat storage heat of a vehicle air conditioner according to any one of claims 20 to 26, wherein a heat insulating gap (11p) is provided between the shell (11d) and the fin (11f). Exchanger.