【０００１】
【発明の属する技術分野】
本発明は、吸収式冷凍機を熱源とする冷媒循環式空調システムに関し、詳しくは冷房時における主な冷媒の循環を上部位置の室外機から流下する冷媒液と戻りの冷媒ガスの比重差によって行う冷媒循環式空調システムに関するものである。
【０００２】
【従来の技術】
従来のこの種の冷媒循環式空調システムとしては図６に示すものがある。これは建物に室外機１と室内機２とを室外機１の方が室内機２より上に位置するように設置すると共に室外機１と室内機２とを冷媒液配管３及び冷媒ガス配管４で連結して、冷房時には室外機１で液化した冷媒液と室内機２で気化した冷媒ガスの比重差により冷媒を自然循環させ、暖房時には室外機１で気化した冷媒ガスと室内機２で液化した冷媒液を建物の下部部位に設けた循環ポンプ５により強制循環させるようにしたものであり、循環ポンプ５と並列に冷房時に開き暖房時に閉じる冷暖切り替え弁６が介装されている。７は室外機１の熱交換器である。この構成によれば、冷房時の冷媒搬送に自然循環方式を採用しているために電力費がかからず、ランニングコストを大幅に節減できる上、騒音も低減できるという利点がある。しかし、大型のビルや横長のビルのように１階当たりの部屋数の多い建物では、水平方向への冷媒搬送にエネルギーが多く消費されるために、自然循環方式の採用が困難となるという問題がある。
【０００３】
この問題を解決するものとして本特許出願人は先に図７に示すような冷媒循環式空調システムを提案した。このシステムのものは図６と基本的に同じであるが、室外機１の冷媒液配管３にタンク８と補助ポンプ９と定差圧弁１０と冷暖切り替え弁１１を設けた点だけが異なる。タンク８は熱交換器７で凝縮した冷媒液を受けるものであって、熱交換器７の下方に配置して熱交換器７に直列に接続してある。また補助ポンプ９は上記タンク８に連続するようにタンク８と直列に接続してある。また定差圧弁１０や冷暖切り替え弁１１はタンク８や補助ポンプ９と並列になるように冷媒液配管３に接続してある。しかして冷房時には室外機１で液化された冷媒液が図７の実線の矢印に示されるように、各冷媒液配管３を通って各室内機２に供給され、室内機２で気化された冷媒ガスが冷媒ガス配管４を通って室外機１へ還流する。このとき冷媒液と冷媒ガスの比重差を利用して行うことができて、冷媒の循環は主に自然循環式で行われるようになっているが、冷房時の冷媒液の自然循環の高低差不足を補うために補助ポンプ９が駆動され、水平配管が長くても送液圧力の不足を生じないようになっている。このとき定差圧弁１０は補助ポンプ９の出口側の圧力が所定以上になると冷媒液を戻す作用をするものであって、補助ポンプ９の出口側の圧力が一定以上にならないようにするためのものである。またタンク８は補助ポンプ９が空運転しないように冷媒液を溜めるものである。なお、冷房時には冷暖切り替え弁６が開かれていると共に冷暖切り替え弁１１が閉じられている。一方、暖房時は冷暖切り替え弁６が閉じられると共に冷暖切り替え弁１１が開かれ、循環ポンプ５を駆動して図７の破線の矢印のように室外機１で気化した冷媒ガスが降下させると共に室内機２で液化した冷媒液を上昇させるように強制循環させられる。
【０００４】
【発明が解決しようとする課題】
ところで、上記のような図７のシステムの場合、冷房時に補助ポンプ９を駆動することで自然循環式のヘッド不足を補って水平配管が長くても冷媒液を送ることができるが、補助ポンプ９の空運転を防止するタンク８に凝縮した冷媒液が落ちにくくて補助ポンプ９により冷媒液の移送が円滑に行われないことがある。つまり、熱交換器７とタンク８とを直列に接続しているために上に位置する熱交換器７と下に位置するタンク８とに落差を設けなければ熱交換器７で凝縮した冷媒液がタンク８に落ちてきにくく、また熱交換器７とタンク８との距離が離れていると冷媒液がタンク８に落ちてきにくくなる。ところが、室外機１で熱交換器７とタンク８とに十分な落差を設けたりした場合、室外機１が大型になるなど新たな問題が生じる。また上記の構造の場合、冷房用の熱交換器と暖房用の熱交換器とが同じものである場合にしか対応できないという問題もある。
【０００５】
本発明は叙述の点に鑑みてなされたものであって、熱交換器とタンクに落差を設けたりしなくても冷房時に凝縮した冷媒液をスムーズに溜めて補助ポンプで供給でき、また冷房用の熱交換器と暖房用の熱交換器を別々のものにできるようにすることを課題とする。
【０００６】
【課題を解決するための手段】
上記課題を解決するために本発明の冷媒循環式空調システムは次の特徴を有している。本発明の第１の特徴は、建物に室外機１と室内機２とを室外機１の方が室内機２より上に位置するように設置すると共に室外機１と室内機２とを冷媒配管で連結して、冷房時には主に室外機１で液化した冷媒液と室内機２で気化した冷媒ガスの比重差により冷媒を循環させるようにした冷媒循環式空調システムにおいて、室外機１の熱交換器７と並列となるように室外機１の冷媒液配管３や冷媒ガス配管４にタンク８を接続し、上記タンク８との合流点より下流側で室外機１の冷媒液配管３に冷媒液を室内機２側に送る補助ポンプ９を配置し、冷房時において、熱交換器７と連通したタンク８に熱交換器７で凝縮した冷媒液を連通管の原理により溜めると共に該タンク８の冷媒液が補助ポンプ９によって室内機２側に供給されるようにして成ることを特徴とする。熱交換器７とタンク８とを冷媒液配管３や冷媒ガス配管４に並列に接続したことにより、熱交換器７とタンク８とに落差がなくても、熱交換器７とタンク８とが離れていても、熱交換器７とタンク８とが連通管の原理で連通しているために熱交換器７で凝縮した冷媒液がスムーズに溜まり、冷媒液を補助ポンプ９でスムーズに送ることができる。これにより室外機１の熱交換器７やタンク８の配置に制約を受けることなく、室外機１が大型になったりする弊害がない。
【０００７】
本発明の第２の特徴は、建物に室外機１と室内機２とを室外機１の方が室内機２より上に位置するように設置すると共に室外機１と室内機２とを冷媒配管で連結して、冷房時には主に室外機１で液化した冷媒液と室内機２で気化した冷媒ガスの比重差により冷媒を循環させ、暖房時には室外機１で気化した冷媒ガスと室内機２で液化した冷媒液を建物下部部位に設けた循環ポンプ５により強制循環させるようにした冷媒循環式空調システムにおいて、室外機１の冷媒液配管３と冷媒ガス配管４との間に冷房用の熱交換器７と暖房用の熱交換器１２とをこれらが並列に並ぶと共に暖房用の熱交換器１２が冷房用の熱交換器７より室内機２側の経路に位置するように接続し、冷房用の熱交換器７と暖房用の熱交換器１２との間でこれらと並列になるようにタンク８を室外機１の冷媒液配管３や冷媒ガス配管４に接続し、タンク８と暖房用の熱交換器１２との間で冷媒液配管３に冷媒液を室内機２側に送る補助ポンプ９を配置し、冷房時において、熱交換器７と連通したタンク８に熱交換器７で凝縮した冷媒液を連通管の原理により溜めると共に該タンク８の冷媒液が補助ポンプ９によって室内機２側に供給されるようにして成ることを特徴とする。冷房用の熱交換器７とタンク８とを冷媒液配管３や冷媒ガス配管４に並列に接続したことにより、熱交換器７とタンク８とに落差がなくても、熱交換器７とタンク８とが離れていても、熱交換器７とタンク８とが連通管の原理で連通しているために冷房時に熱交換器７で凝縮した冷媒液がスムーズに溜まり、冷媒液を補助ポンプ９でスムーズに送ることができる。これにより室外機１の熱交換器７やタンク８の配置に制約を受けることなく、室外機１が大型になったりする弊害がない。また冷房時には室内機２で気化した冷媒ガスが冷媒ガス配管４を介して室外機１の冷房用の熱交換器７に送られ、冷房用の熱交換器７で液化した冷媒液が室内機２に送られものであり、暖房時には室内機２で液化した冷媒液が冷媒液配管３を介して室外機１の暖房用の熱交換器１２に送られ、暖房用の熱交換器１２で冷媒液が気化され、気化された冷媒ガスが室内機２に送られるものであり、冷房時と暖房時に別々の熱交換器７，１２を用いて効果的に冷房や暖房ができる。
【０００８】
また本発明の第３の特徴は、第２の特徴において、補助ポンプ９と暖房用の熱交換器１２との間で冷媒液配管３に補助ポンプ９側から送られる冷媒液のみを通過させる逆止弁１３を設けて成ることを特徴とする。この場合、暖房運転時、冷媒液が補助ポンプ９側に送られるのを防止し、暖房用の熱交換器１２に冷媒液を確実に送ることができる。
【０００９】
また本発明の第４の特徴は、第２又は第３の特徴において、暖房用の熱交換器１２と直列に冷暖切り替え弁１５を設けて成ることを特徴とする。この場合、冷暖切り替え弁１５の切り替えにて冷房時には冷房用の熱交換器７のみに冷媒が流れ、暖房時には暖房用の熱交換器１２のみに冷媒が流れるようにできる。
【００１０】
また本発明の第５の特徴は、第２乃至第４の特徴において、暖房運転時でタンク８に所定以上の冷媒液が溜まっているとき補助ポンプ９を駆動するようにして成ることを特徴とする。この場合、暖房運転時に冷媒が冷房用の熱交換器７に流入しても補助ポンプ９にて戻すことができる。
【００１１】
また本発明の第６の特徴は、第１乃至第５の特徴において、補助ポンプ９からの送液流量を一定に保つ手段を設けて成ることを特徴とする。この場合、補助ポンプ９で冷媒液を送るとき、送液流量を一定に保つことができて安定した送液をすることができる。
【００１２】
【発明の実施の形態】
まず、図１に示す実施の形態から述べる。
【００１３】
建物には室外機１と室内機２とが室外機１が室内機２より上に位置するように設置されている。例えば室外機１は建物の屋上に設置されており、室内機２は建物内の複数の部屋に設置されている。この室外機１と複数個の室内機２とが冷媒液配管３及び冷媒ガス配管４にて接続されている。そして冷房時には室外機１で液化された冷媒液が、図１の実線の矢印に示すように冷媒液配管３を通って各室内機２に供給され、室内機２で気化された冷媒ガスが冷媒ガス配管４を通って室外機１へ還流する。このとき、冷媒液と冷媒ガスとの比重差を利用できるので、冷媒の循環は主に自然循環方式で行われる。一方暖房時には、図１の破線の矢印に示すように室外機１で気化した冷媒ガスが降下し、室内機２で液化した冷媒液を上昇させる必要があるので、冷媒の循環は建物下部位置に設けた循環ポンプ５にて強制的に行われる。このときの冷房と暖房の切り換えは冷暖切り替え弁６によって行われるものであり、この冷暖切り替え弁６は冷房時に開き、暖房時に閉じるようになっている。こうして冷房時の冷媒搬送に主に自然循環方式を採用することにより、夏季における電力コストを節減すると共に、騒音を低減しているのである。
【００１４】
室外機１では冷媒液配管３と冷媒ガス配管４との間に冷房用の熱交換器７と暖房用の熱交換器１２とが熱交換器７と熱交換器１２が並列になるように接続してある。この熱交換器７，１２は例えば熱交換コイルにて形成されている。冷房用の熱交換器７と暖房用の熱交換器１２とは配管系で冷房用の熱交換器７より暖房用の熱交換器１２を室内機２側に位置させてある。また冷房用の熱交換器７と暖房用の熱交換器１２との間でこれらと並列になるように冷媒液配管３と冷媒ガス配管４との間にタンク８を接続してある。冷房用の熱交換器７と暖房用の熱交換器１２との間で室外機１の冷媒液配管３に補助ポンプ９を配置してあり、この補助ポンプ９を駆動することで補助的に冷媒液を送ることができるようになっている。この補助ポンプ９は冷媒液を数ｍの高さへ汲み上げることができる程度の小能力のもので十分であり、設備コストやランニングコストに殆ど影響を及ぼさないものである。上記タンク８にはフロートスイッチのような液面計１４を装着してあり、タンク８の冷媒液の液面を検知してタンク８の液面が所定高さ以上あるとき補助ポンプ９を駆動して冷媒液を送ることができるようになっている。この冷媒液配管３の補助ポンプ９の出口側に補助ポンプ９側からは冷媒液が流れるが、逆には流れない逆止弁１３を補助ポンプ９と直列に接続してある。また室外機１の冷媒液配管３には補助ポンプ９や逆止弁１３と並列になるように定差圧弁１０を接続してある。また暖房用の熱交換器１２と直列に冷暖切り替え弁１５を接続してある。
【００１５】
しかして冷暖切り替え弁１５を閉じて暖房用の熱交換器１２に冷媒が流れないようにした状態で冷房を行うのであるが、冷房時には室内機２から冷媒ガス配管４を通って冷房用の熱交換器７に送られてきた冷媒ガスは熱交換器７で熱交換して凝縮することにより液化して冷媒液となり、凝縮して溜まった冷媒液が補助ポンプ９にて送られ、補助ポンプ９による補助的な送りと、比重差による循環にて室内機２に送られる。この場合、補助ポンプ９にて送ることにより水平配管が長くてもヘッドの不足分を補って室内機２に確実に送ることができる。またタンク８に冷媒液を溜め、タンク８の液面が所定以上の液位のとき補助ポンプ９を駆動して送ることができるために補助ポンプ９を空運転するおそれがない。また冷房用の熱交換器７とタンク８とを並列に接続して熱交換器７とタンク８とが連通管の原理で連通しているため、熱交換器７とタンク８との落差が小さくても、これらの間の距離が離れていても、タンク８に凝縮した冷媒液をスムーズに溜めることができて冷媒液の送りがスムーズに行われる。また補助ポンプ９と並列に定差圧弁１０を設けてあるために補助ポンプ９の出口側の圧力が高くなると定差圧弁１０を介して冷媒液が戻り、冷媒液が必要以上の圧力に加圧されて送られることがない。また冷暖切り替え弁１５を開いて暖房用の熱交換器１２に冷媒が流れるようにした状態で暖房を行うのであるが、暖房時には室内機２から冷媒液配管３を通って暖房用の熱交換器１２に送られてきた冷媒液は熱交換器１２で熱交換して気化して冷媒ガスとなり、冷媒ガスが冷媒ガス配管４を通って室内機２に送られる。暖房時に冷媒液が補助ポンプ９の方に流れても逆止弁１３があるために流れることがない。また冷媒ガスの一部が冷房用の熱交換器７に流れて凝縮することがあるが、このときタンク８の液面が所定高さ以上になると補助ポンプ９が駆動されて冷媒液が戻される。
【００１６】
また、補助ポンプ９から送る冷媒液の流量を一定に保つためには次の手段が用いられる。その一例としては図２（ａ）に示すように補助ポンプ９の下流側に定流量弁１８を設けるものがある。この場合、定流量弁１８にて流量を一定に保って冷媒液を送ることができる。また他例としては図１や図２（ｂ）に示すように補助ポンプ９と並列に定差圧弁１０を設けるものがある。この場合、補助ポンプ９の吐出側の圧力を一定に保って送液流量を一定に保つことができる。さらに他例としては図３（ｃ）に示すように補助ポンプ９の回転数を変化させるものがある。この場合、室内機２からの負荷信号により補助ポンプ９の回転数を制御して送液流量を一定に保つようになっている。
【００１７】
次に図３に示す実施の形態について述べる。本例も図１に示すシステムと基本的に同じであり、同じ部分に同じ符号を付して詳しい説明は省略する。図３R>３に示すものは、図１の暖房用の熱交換器１２、冷暖切り替え弁１５、逆止弁１３をなくしたものであり、冷房だけを専用に行うシステムである。この場合も補助ポンプ９にて送ることにより水平配管が長くてもヘッドの不足分を補って室内機２に確実に送ることができる。またタンク８に冷媒液を溜め、タンク８の液面が所定以上の液位のとき補助ポンプ９を駆動して送ることができるために補助ポンプ９を空運転するおそれがない。また冷房用の熱交換器７とタンク８とを並列に接続して熱交換器７とタンク８とが連通管の原理で連通しているため、熱交換器７とタンク８との落差が小さくても、これらの間の距離が離れていても、タンク８に凝縮した冷媒液をスムーズに溜めることができて冷媒液の送りがスムーズに行われる。
【００１８】
次に図４、図５に示す実施の形態について述べる。これらのものも、上記例のものと基本的に同じであり、同じ部品に同じ符号を付して詳しい説明は省略する。この場合、さらに切り替え弁１６を設け、逆止弁１３の配置を変更している。
【００１９】
【発明の効果】
本発明の請求項１の発明は、建物に室外機と室内機とを室外機の方が室内機より上に位置するように設置すると共に室外機と室内機とを冷媒配管で連結して、冷房時には主に室外機で液化した冷媒液と室内機で気化した冷媒ガスの比重差により冷媒を循環させるようにした冷媒循環式空調システムにおいて、室外機の熱交換器と並列となるように室外機の冷媒液配管や冷媒ガス配管にタンクを接続し、上記タンクとの合流点より下流側で室外機の冷媒液配管に冷媒液を室内機側に送る補助ポンプを配置し、冷房時において、熱交換器と連通したタンクに熱交換器で凝縮した冷媒液を連通管の原理により溜めると共に該タンクの冷媒液が補助ポンプによって室内機側に供給されるようにしているので、補助ポンプを駆動することにより主に自然循環で送る冷媒液をさらに補助的に送ることができて水平配管が長くても室内機に冷媒液を確実に送ることができるものであるのは勿論、熱交換器とタンクとを冷媒液配管や冷媒ガス配管に並列に接続したことにより、熱交換器とタンクとに落差がなくても、熱交換器とタンクとが離れていても、熱交換器とタンクとが連通管の原理で連通しているために熱交換器で凝縮した冷媒液がスムーズに溜まり、冷媒液を補助ポンプでスムーズに送ることができるものであり、これにより室外機の熱交換器やタンクの配置に制約を受けることなく、室外機が大型になったりする弊害がないものである。
【００２０】
本発明の請求項２の発明は、建物に室外機と室内機とを室外機の方が室内機より上に位置するように設置すると共に室外機と室内機とを冷媒配管で連結して、冷房時には主に室外機で液化した冷媒液と室内機で気化した冷媒ガスの比重差により冷媒を循環させ、暖房時には室外機で気化した冷媒ガスと室内機で液化した冷媒液を建物下部部位に設けた循環ポンプにより強制循環させるようにした冷媒循環式空調システムにおいて、室外機の冷媒液配管と冷媒ガス配管との間に冷房用の熱交換器と暖房用の熱交換器とをこれらが並列に並ぶと共に暖房用の熱交換器が冷房用の熱交換器より室内機側の経路に位置するように接続し、冷房用の熱交換器と暖房用の熱交換器との間でこれらと並列になるようにタンクを室外機の冷媒液配管や冷媒ガス配管に接続し、タンクと暖房用の熱交換器との間で冷媒液配管に冷媒液を室内機側に送る補助ポンプを配置し、冷房時において、熱交換器と連通したタンクに熱交換器で凝縮した冷媒液を連通管の原理により溜めると共に該タンクの冷媒液が補助ポンプによって室内機側に供給されるようにしているので、冷房時に補助ポンプを駆動することにより主に自然循環で送る冷媒液をさらに補助的に送ることができて水平配管が長くても室内機に冷媒液を確実に送ることができるものであるのは勿論、冷房用の熱交換器とタンクとを冷媒液配管や冷媒ガス配管に並列に接続したことにより、熱交換器とタンクとに落差がなくても、熱交換器とタンクとが離れていても、熱交換器とタンクとが連通管の原理で連通しているために冷房時に熱交換器で凝縮した冷媒液がスムーズに溜まり、冷媒液を補助ポンプでスムーズに送ることができるものであり、これにより室外機の熱交換器やタンクの配置に制約を受けることなく、室外機が大型になったりする弊害がないものであり、また冷房時には室内機で気化した冷媒ガスが冷媒ガス配管を介して室外機の冷房用の熱交換器に送られ、冷房用の熱交換器で液化した冷媒液が室内機に送られ、暖房時には室内機で液化した冷媒液が冷媒液配管を介して室外機の暖房用の熱交換器に送られ、暖房用の熱交換器で冷媒液が気化され、気化された冷媒ガスが室内機に送られるものであって、冷房時と暖房時に別々の熱交換器を用いて効果的に冷房や暖房ができるものである。
【００２１】
また本発明の請求項３の発明は、請求項２において、補助ポンプと暖房用の熱交換器との間で冷媒液配管に補助ポンプ側から送られる冷媒液のみを通過させる逆止弁を設けているので、暖房運転時、冷媒液が補助ポンプ側に送られるのを防止して暖房用の熱交換器に冷媒液を確実に送ることができるものである。
【００２２】
また本発明の請求項４の発明は、請求項２又は請求項３において、暖房用の熱交換器と直列に冷暖切り替え弁を設けているので、冷暖切り替え弁の切り替えにて冷房時には冷房用の熱交換器のみに冷媒が流れ、暖房時には暖房用の熱交換器のみに冷媒が流れるようにできるものである。
【００２３】
また本発明の請求項５の発明は、請求項２乃至請求項４において、暖房運転時でタンクに所定以上の冷媒液が溜まっているとき補助ポンプを駆動するようにしているので、暖房運転時に冷媒が冷房用の熱交換器に流入しても補助ポンプにて戻すことができるものである。
【００２４】
また本発明の請求項６の発明は、請求項１乃至請求項５のいずれかにおいて、補助ポンプからの送液流量を一定に保つ手段を設けているので、補助ポンプで冷媒液を送るとき、送液流量を一定に保つことができて安定した送液をすることができるものである。
【図面の簡単な説明】
【図１】 本発明の実施の形態の一例を示す配管系統図である。
【図２】 （ａ）（ｂ）（ｃ）は同上の補助ポンプからの送液流量を一定に保つ手段を示す系統図である。
【図３】 同上の他例を示す配管系統図である。
【図４】 同上の他例を示す配管系統図である。
【図５】 同上の他例を示す配管系統図である。
【図６】 従来例を示す配管系統図である。
【図７】 上記従来例を進歩させたものの配管系統図である。
【符号の説明】
１ 室外機
２ 室内機
３ 冷媒液配管
４ 冷媒ガス配管
５ 循環ポンプ
６ 冷暖切り替え弁
７ 熱交換器
８ タンク
９ 補助ポンプ
１２ 熱交換器
１３ 逆止弁
１５ 冷暖切り替え弁[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a refrigerant circulation air conditioning system using an absorption chiller as a heat source, and more specifically, the main refrigerant circulation during cooling is performed by the difference in specific gravity between the refrigerant liquid flowing down from the outdoor unit at the upper position and the return refrigerant gas. The present invention relates to a refrigerant circulation air conditioning system.
[0002]
[Prior art]
A conventional refrigerant circulation type air conditioning system of this type is shown in FIG. This is because the outdoor unit 1 and the indoor unit 2 are installed in a building so that the outdoor unit 1 is located above the indoor unit 2, and the outdoor unit 1 and the indoor unit 2 are connected to the refrigerant liquid pipe 3 and the refrigerant gas pipe 4. The refrigerant is naturally circulated by the difference in specific gravity between the refrigerant liquid liquefied in the outdoor unit 1 and the refrigerant gas vaporized in the indoor unit 2 during cooling, and the refrigerant gas vaporized in the outdoor unit 1 and liquefied in the indoor unit 2 during heating. The refrigerant liquid is forcibly circulated by a circulation pump 5 provided at a lower part of the building, and a cooling / heating switching valve 6 that opens in cooling and closes in heating is interposed in parallel with the circulation pump 5. Reference numeral 7 denotes a heat exchanger of the outdoor unit 1. According to this configuration, since the natural circulation system is adopted for refrigerant conveyance during cooling, there is an advantage that no power cost is required, running costs can be significantly reduced, and noise can be reduced. However, in buildings with a large number of rooms per floor, such as large buildings and horizontally long buildings, a large amount of energy is consumed for transporting refrigerant in the horizontal direction, making it difficult to adopt the natural circulation method. There is.
[0003]
In order to solve this problem, the present applicant previously proposed a refrigerant circulation type air conditioning system as shown in FIG. The system is basically the same as that shown in FIG. 6 except that a tank 8, an auxiliary pump 9, a constant differential pressure valve 10, and a cooling / heating switching valve 11 are provided in the refrigerant liquid pipe 3 of the outdoor unit 1. The tank 8 receives the refrigerant liquid condensed in the heat exchanger 7 and is disposed below the heat exchanger 7 and connected in series to the heat exchanger 7. The auxiliary pump 9 is connected in series with the tank 8 so as to be continuous with the tank 8. The constant differential pressure valve 10 and the cooling / heating switching valve 11 are connected to the refrigerant liquid pipe 3 so as to be in parallel with the tank 8 and the auxiliary pump 9. Thus, during cooling, the refrigerant liquid liquefied in the outdoor unit 1 is supplied to each indoor unit 2 through each refrigerant liquid pipe 3 as indicated by the solid line arrows in FIG. The gas flows back to the outdoor unit 1 through the refrigerant gas pipe 4. At this time, the difference in specific gravity between the refrigerant liquid and the refrigerant gas can be used, and the circulation of the refrigerant is mainly performed by a natural circulation type. However, the difference in the natural circulation of the refrigerant liquid during cooling is different. In order to compensate for the shortage, the auxiliary pump 9 is driven so that the liquid feeding pressure does not become short even if the horizontal pipe is long. At this time, the constant differential pressure valve 10 functions to return the refrigerant liquid when the pressure on the outlet side of the auxiliary pump 9 exceeds a predetermined value, and prevents the pressure on the outlet side of the auxiliary pump 9 from exceeding a certain level. Is. Further, the tank 8 stores the refrigerant liquid so that the auxiliary pump 9 does not run idle. During cooling, the cooling / heating switching valve 6 is opened and the cooling / heating switching valve 11 is closed. On the other hand, at the time of heating, the cooling / heating switching valve 6 is closed and the cooling / heating switching valve 11 is opened, and the circulation pump 5 is driven to lower the refrigerant gas evaporated in the outdoor unit 1 as indicated by the broken line arrow in FIG. The refrigerant liquid liquefied by the machine 2 is forcedly circulated so as to rise.
[0004]
[Problems to be solved by the invention]
By the way, in the case of the system of FIG. 7 as described above, the auxiliary pump 9 is driven at the time of cooling to compensate for the shortage of the natural circulation type head and the refrigerant liquid can be sent even if the horizontal pipe is long. In some cases, the refrigerant liquid condensed in the tank 8 that prevents the idling of the oil is not easily dropped, and the auxiliary pump 9 may not smoothly transfer the refrigerant liquid. In other words, since the heat exchanger 7 and the tank 8 are connected in series, the refrigerant liquid condensed in the heat exchanger 7 unless a drop is provided between the heat exchanger 7 located above and the tank 8 located below. Is difficult to fall into the tank 8, and if the distance between the heat exchanger 7 and the tank 8 is large, the refrigerant liquid is unlikely to fall into the tank 8. However, when a sufficient drop is provided between the heat exchanger 7 and the tank 8 in the outdoor unit 1, new problems such as an increase in the size of the outdoor unit 1 occur. In the case of the above-described structure, there is also a problem that it can be dealt with only when the cooling heat exchanger and the heating heat exchanger are the same.
[0005]
The present invention has been made in view of the description, and it is possible to smoothly collect the refrigerant liquid condensed at the time of cooling without supplying a drop between the heat exchanger and the tank and to supply the refrigerant liquid with an auxiliary pump. It is an object of the present invention to enable separate heat exchangers for heating and heat exchangers for heating.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, the refrigerant circulation air conditioning system of the present invention has the following characteristics. The first feature of the present invention is that the outdoor unit 1 and the indoor unit 2 are installed in a building so that the outdoor unit 1 is positioned above the indoor unit 2 and the outdoor unit 1 and the indoor unit 2 are connected to the refrigerant pipe. In the refrigerant circulation air conditioning system in which the refrigerant is circulated mainly by the specific gravity difference between the refrigerant liquid liquefied in the outdoor unit 1 and the refrigerant gas vaporized in the indoor unit 2 during cooling, the heat exchange of the outdoor unit 1 A tank 8 is connected to the refrigerant liquid pipe 3 and the refrigerant gas pipe 4 of the outdoor unit 1 so as to be in parallel with the vessel 7, and the refrigerant liquid is connected to the refrigerant liquid pipe 3 of the outdoor unit 1 on the downstream side from the junction with the tank 8. An auxiliary pump 9 is disposed to the indoor unit 2 side, and during cooling, the refrigerant liquid condensed in the heat exchanger 7 is accumulated in the tank 8 communicated with the heat exchanger 7 according to the principle of the communication pipe, and the refrigerant in the tank 8 The liquid is supplied to the indoor unit 2 side by the auxiliary pump 9. It is characterized in. Since the heat exchanger 7 and the tank 8 are connected in parallel to the refrigerant liquid pipe 3 and the refrigerant gas pipe 4, the heat exchanger 7 and the tank 8 can be connected even if there is no drop between the heat exchanger 7 and the tank 8. Even if the heat exchanger 7 and the tank 8 are separated, the refrigerant liquid condensed in the heat exchanger 7 is smoothly accumulated because the heat exchanger 7 and the tank 8 are communicated by the principle of the communication pipe, and the refrigerant liquid is smoothly sent by the auxiliary pump 9. Can do. Thus, there is no adverse effect that the outdoor unit 1 becomes large without being restricted by the arrangement of the heat exchanger 7 and the tank 8 of the outdoor unit 1.
[0007]
The second feature of the present invention is that the outdoor unit 1 and the indoor unit 2 are installed in a building so that the outdoor unit 1 is positioned above the indoor unit 2 and the outdoor unit 1 and the indoor unit 2 are connected to the refrigerant pipe. The refrigerant is circulated by the specific gravity difference between the refrigerant liquid liquefied in the outdoor unit 1 and the refrigerant gas vaporized in the indoor unit 2 during cooling, and the refrigerant gas vaporized in the outdoor unit 1 and the indoor unit 2 during heating. In the refrigerant circulation air conditioning system in which the liquefied refrigerant liquid is forcibly circulated by the circulation pump 5 provided in the lower part of the building, heat exchange for cooling is performed between the refrigerant liquid pipe 3 and the refrigerant gas pipe 4 of the outdoor unit 1. The air conditioner 7 and the heating heat exchanger 12 are arranged in parallel, and the heating heat exchanger 12 is connected so as to be located on the path closer to the indoor unit 2 than the cooling heat exchanger 7. Between the heat exchanger 7 and the heating heat exchanger 12 in parallel. Thus, the tank 8 is connected to the refrigerant liquid pipe 3 and the refrigerant gas pipe 4 of the outdoor unit 1, and the refrigerant liquid is sent to the refrigerant liquid pipe 3 between the tank 8 and the heat exchanger 12 for heating to the indoor unit 2 side. An auxiliary pump 9 is arranged, and at the time of cooling, the refrigerant liquid condensed in the heat exchanger 7 is accumulated in the tank 8 communicating with the heat exchanger 7 according to the principle of the communication pipe, and the refrigerant liquid in the tank 8 is stored indoors by the auxiliary pump 9. It is characterized in that it is supplied to the machine 2 side. Since the cooling heat exchanger 7 and the tank 8 are connected in parallel to the refrigerant liquid pipe 3 and the refrigerant gas pipe 4, the heat exchanger 7 and the tank can be connected even if there is no drop between the heat exchanger 7 and the tank 8. Even if the heat exchanger 7 and the tank 8 are separated from each other, the refrigerant fluid condensed in the heat exchanger 7 during cooling is smoothly accumulated because the heat exchanger 7 and the tank 8 communicate with each other by the principle of the communication pipe. Can be sent smoothly. Thus, there is no adverse effect that the outdoor unit 1 becomes large without being restricted by the arrangement of the heat exchanger 7 and the tank 8 of the outdoor unit 1. During cooling, the refrigerant gas evaporated in the indoor unit 2 is sent to the cooling heat exchanger 7 of the outdoor unit 1 through the refrigerant gas pipe 4, and the refrigerant liquid liquefied in the cooling heat exchanger 7 is converted into the indoor unit 2. At the time of heating, the refrigerant liquid liquefied in the indoor unit 2 is sent to the heating heat exchanger 12 of the outdoor unit 1 through the refrigerant liquid pipe 3, and the refrigerant liquid is heated in the heating heat exchanger 12 Is vaporized, and the vaporized refrigerant gas is sent to the indoor unit 2 and can be effectively cooled and heated using separate heat exchangers 7 and 12 during cooling and heating.
[0008]
The third feature of the present invention is the reverse of the second feature, wherein only the refrigerant liquid sent from the auxiliary pump 9 side to the refrigerant liquid pipe 3 is passed between the auxiliary pump 9 and the heat exchanger 12 for heating. A stop valve 13 is provided. In this case, the refrigerant liquid can be prevented from being sent to the auxiliary pump 9 side during the heating operation, and the refrigerant liquid can be reliably sent to the heating heat exchanger 12.
[0009]
The fourth feature of the present invention is that, in the second or third feature, a cooling / heating switching valve 15 is provided in series with the heat exchanger 12 for heating. In this case, the cooling / heating switching valve 15 can be switched so that the refrigerant flows only in the cooling heat exchanger 7 during cooling, and only in the heating heat exchanger 12 during heating.
[0010]
The fifth feature of the present invention is that, in the second to fourth features, the auxiliary pump 9 is driven when a predetermined amount or more of refrigerant liquid is accumulated in the tank 8 during heating operation. To do. In this case, even if the refrigerant flows into the cooling heat exchanger 7 during the heating operation, it can be returned by the auxiliary pump 9.
[0011]
The sixth feature of the present invention is characterized in that in the first to fifth features, there is provided means for keeping the liquid flow rate from the auxiliary pump 9 constant. In this case, when the refrigerant liquid is sent by the auxiliary pump 9, the liquid supply flow rate can be kept constant and stable liquid supply can be performed.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
First, the embodiment shown in FIG. 1 will be described.
[0013]
In the building, the outdoor unit 1 and the indoor unit 2 are installed such that the outdoor unit 1 is positioned above the indoor unit 2. For example, the outdoor unit 1 is installed on the roof of a building, and the indoor unit 2 is installed in a plurality of rooms in the building. The outdoor unit 1 and a plurality of indoor units 2 are connected by a refrigerant liquid pipe 3 and a refrigerant gas pipe 4. During cooling, the refrigerant liquid liquefied in the outdoor unit 1 is supplied to each indoor unit 2 through the refrigerant liquid pipe 3 as indicated by the solid line arrow in FIG. 1, and the refrigerant gas vaporized in the indoor unit 2 is the refrigerant. It returns to the outdoor unit 1 through the gas pipe 4. At this time, since the specific gravity difference between the refrigerant liquid and the refrigerant gas can be used, the refrigerant is circulated mainly by a natural circulation method. On the other hand, during heating, the refrigerant gas vaporized in the outdoor unit 1 falls as indicated by the dashed arrows in FIG. 1 and the refrigerant liquid liquefied in the indoor unit 2 needs to be raised. This is forcibly performed by the circulating pump 5 provided. Switching between cooling and heating at this time is performed by a cooling / heating switching valve 6, and this cooling / heating switching valve 6 is opened during cooling and closed during heating. Thus, by adopting a natural circulation system mainly for refrigerant conveyance during cooling, the power cost in summer is reduced and noise is reduced.
[0014]
In the outdoor unit 1, a cooling heat exchanger 7 and a heating heat exchanger 12 are connected between the refrigerant liquid pipe 3 and the refrigerant gas pipe 4 so that the heat exchanger 7 and the heat exchanger 12 are in parallel. It is. The heat exchangers 7 and 12 are formed by, for example, heat exchange coils. The heat exchanger 7 for cooling and the heat exchanger 12 for heating are piping systems, and the heat exchanger 12 for heating is positioned closer to the indoor unit 2 than the heat exchanger 7 for cooling. Further, a tank 8 is connected between the refrigerant liquid pipe 3 and the refrigerant gas pipe 4 so as to be in parallel between the cooling heat exchanger 7 and the heating heat exchanger 12. An auxiliary pump 9 is arranged in the refrigerant liquid pipe 3 of the outdoor unit 1 between the heat exchanger 7 for cooling and the heat exchanger 12 for heating, and the auxiliary pump 9 is driven to assist the refrigerant. The liquid can be sent. The auxiliary pump 9 needs only to have a small capacity capable of pumping the refrigerant liquid to a height of several meters, and has little influence on equipment cost and running cost. The tank 8 is equipped with a liquid level gauge 14 such as a float switch. When the liquid level of the refrigerant liquid in the tank 8 is detected and the liquid level of the tank 8 exceeds a predetermined level, the auxiliary pump 9 is driven. The refrigerant liquid can be sent. A check valve 13 is connected in series with the auxiliary pump 9 to the outlet side of the auxiliary pump 9 of the refrigerant liquid pipe 3, but the refrigerant liquid flows from the auxiliary pump 9 side but does not flow reversely. A constant differential pressure valve 10 is connected to the refrigerant liquid pipe 3 of the outdoor unit 1 so as to be in parallel with the auxiliary pump 9 and the check valve 13. In addition, a cooling / heating switching valve 15 is connected in series with the heat exchanger 12 for heating.
[0015]
Thus, the cooling / heating switching valve 15 is closed and cooling is performed in a state in which the refrigerant does not flow to the heating heat exchanger 12. At the time of cooling, the cooling heat is passed from the indoor unit 2 through the refrigerant gas pipe 4. The refrigerant gas sent to the exchanger 7 is liquefied by heat exchange in the heat exchanger 7 and condensed to become a refrigerant liquid, and the condensed and accumulated refrigerant liquid is sent by the auxiliary pump 9. Is sent to the indoor unit 2 by an auxiliary feed due to and by circulation due to a difference in specific gravity. In this case, by sending with the auxiliary pump 9, even if the horizontal pipe is long, the shortage of the head can be compensated and it can be reliably sent to the indoor unit 2. Further, since the refrigerant liquid is stored in the tank 8 and the auxiliary pump 9 can be driven and sent when the liquid level of the tank 8 is at a predetermined level or higher, there is no fear that the auxiliary pump 9 is idling. In addition, since the cooling heat exchanger 7 and the tank 8 are connected in parallel and the heat exchanger 7 and the tank 8 communicate with each other by the principle of the communication pipe, the difference between the heat exchanger 7 and the tank 8 is small. Even if the distance between them is long, the refrigerant liquid condensed in the tank 8 can be stored smoothly, and the refrigerant liquid is smoothly fed. Since the constant differential pressure valve 10 is provided in parallel with the auxiliary pump 9, when the pressure on the outlet side of the auxiliary pump 9 increases, the refrigerant liquid returns via the constant differential pressure valve 10, and the refrigerant liquid is pressurized to an excessive pressure. Never sent. Heating is performed in a state where the cooling / heating switching valve 15 is opened so that the refrigerant flows into the heat exchanger 12 for heating. During heating, the heating heat exchanger passes through the refrigerant liquid pipe 3 from the indoor unit 2. The refrigerant liquid sent to 12 is heat-exchanged by the heat exchanger 12 and vaporized to become refrigerant gas, and the refrigerant gas is sent to the indoor unit 2 through the refrigerant gas pipe 4. Even if the refrigerant liquid flows toward the auxiliary pump 9 during heating, it does not flow because of the check valve 13. In addition, a part of the refrigerant gas may flow to the cooling heat exchanger 7 and condense. At this time, when the liquid level of the tank 8 exceeds a predetermined level, the auxiliary pump 9 is driven to return the refrigerant liquid. .
[0016]
In order to keep the flow rate of the refrigerant liquid sent from the auxiliary pump 9 constant, the following means is used. As an example, there is one in which a constant flow valve 18 is provided on the downstream side of the auxiliary pump 9 as shown in FIG. In this case, the refrigerant liquid can be sent while the flow rate is kept constant by the constant flow valve 18. As another example, as shown in FIG. 1 and FIG. 2 (b), a constant differential pressure valve 10 is provided in parallel with the auxiliary pump 9. In this case, the pressure on the discharge side of the auxiliary pump 9 can be kept constant, and the liquid feed flow rate can be kept constant. Still another example is one that changes the rotational speed of the auxiliary pump 9 as shown in FIG. In this case, the rotational speed of the auxiliary pump 9 is controlled by a load signal from the indoor unit 2 so as to keep the liquid supply flow rate constant.
[0017]
Next, the embodiment shown in FIG. 3 will be described. This example is also basically the same as the system shown in FIG. 3R> 3 is a system in which the heating heat exchanger 12, the cooling / heating switching valve 15 and the check valve 13 in FIG. 1 are eliminated, and only the cooling is performed. Also in this case, even if the horizontal piping is long by sending with the auxiliary pump 9, the shortage of the head can be compensated and sent to the indoor unit 2 reliably. Further, since the refrigerant liquid is stored in the tank 8 and the auxiliary pump 9 can be driven and sent when the liquid level of the tank 8 is at a predetermined level or higher, there is no fear that the auxiliary pump 9 is idling. In addition, since the cooling heat exchanger 7 and the tank 8 are connected in parallel and the heat exchanger 7 and the tank 8 communicate with each other by the principle of the communication pipe, the difference between the heat exchanger 7 and the tank 8 is small. Even if the distance between them is long, the refrigerant liquid condensed in the tank 8 can be stored smoothly, and the refrigerant liquid is smoothly fed.
[0018]
Next, the embodiment shown in FIGS. 4 and 5 will be described. These are also basically the same as those in the above example, and the same components are denoted by the same reference numerals and detailed description thereof is omitted. In this case, the switching valve 16 is further provided, and the arrangement of the check valve 13 is changed.
[0019]
【The invention's effect】
In the invention of claim 1 of the present invention, the outdoor unit and the indoor unit are installed in a building so that the outdoor unit is positioned above the indoor unit, and the outdoor unit and the indoor unit are connected by a refrigerant pipe. In a refrigerant circulation air conditioning system that circulates refrigerant mainly due to the specific gravity difference between the refrigerant liquid liquefied in the outdoor unit and the refrigerant gas vaporized in the indoor unit during cooling, the outdoor unit is arranged in parallel with the heat exchanger of the outdoor unit. A tank is connected to the refrigerant liquid pipe and refrigerant gas pipe of the machine, and an auxiliary pump that sends the refrigerant liquid to the indoor unit side is arranged in the refrigerant liquid pipe of the outdoor unit downstream from the junction with the tank. The refrigerant liquid condensed in the heat exchanger is stored in the tank connected to the heat exchanger according to the principle of the communication pipe, and the refrigerant liquid in the tank is supplied to the indoor unit side by the auxiliary pump. Mainly by nature Refrigerant liquid sent by the ring can be further supplementarily sent, and even if the horizontal pipe is long, the refrigerant liquid can be surely sent to the indoor unit. Of course, the heat exchanger and the tank are connected to the refrigerant liquid pipe. Even if there is no drop between the heat exchanger and the tank, or even if the heat exchanger and the tank are separated, the heat exchanger and the tank communicate with each other according to the principle of the communication pipe. Therefore, the refrigerant liquid condensed in the heat exchanger can be collected smoothly, and the refrigerant liquid can be sent smoothly by the auxiliary pump. This restricts the arrangement of the heat exchanger and tank of the outdoor unit. Therefore, there is no harmful effect that the outdoor unit becomes large.
[0020]
Invention of Claim 2 of this invention installs an outdoor unit and an indoor unit in a building so that the direction of an outdoor unit may be located above an indoor unit, and connects an outdoor unit and an indoor unit with refrigerant piping, During cooling, the refrigerant is circulated mainly due to the difference in specific gravity between the refrigerant liquid liquefied by the outdoor unit and the refrigerant gas vaporized by the indoor unit. In a refrigerant circulation air conditioning system that is forcibly circulated by a provided circulation pump, a cooling heat exchanger and a heating heat exchanger are arranged in parallel between the refrigerant liquid pipe and the refrigerant gas pipe of the outdoor unit. Are connected so that the heat exchanger for heating is located in the path on the indoor unit side from the heat exchanger for cooling, and in parallel between the heat exchanger for cooling and the heat exchanger for heating. Make the tank into the outdoor unit's refrigerant liquid piping or refrigerant gas An auxiliary pump is connected to the pipe and between the tank and the heat exchanger for heating to send refrigerant liquid to the indoor unit side in the refrigerant liquid piping, and during cooling, the heat exchanger is connected to the tank connected to the heat exchanger. The refrigerant liquid condensed in the tank is stored according to the principle of the communication pipe, and the refrigerant liquid in the tank is supplied to the indoor unit side by the auxiliary pump. Therefore, the auxiliary liquid is driven mainly by natural circulation during cooling. Of course, the refrigerant liquid can be sent in an auxiliary manner, and even if the horizontal pipe is long, the refrigerant liquid can be reliably sent to the indoor unit. Of course, the cooling heat exchanger and the tank are connected to the refrigerant liquid pipe. Even if there is no drop between the heat exchanger and the tank, or even if the heat exchanger and the tank are separated, the heat exchanger and the tank communicate with each other according to the principle of the communication pipe. Because of this, heat exchangers As a result, the refrigerant liquid can be collected smoothly, and the refrigerant liquid can be sent smoothly by the auxiliary pump. This makes it possible to increase the size of the outdoor unit without being restricted by the arrangement of the heat exchanger and tank of the outdoor unit. The refrigerant gas vaporized in the indoor unit during cooling is sent to the cooling heat exchanger of the outdoor unit through the refrigerant gas pipe, and the refrigerant liquid liquefied in the cooling heat exchanger is The refrigerant liquid that is sent to the indoor unit and liquefied in the indoor unit during heating is sent to the heat exchanger for heating of the outdoor unit through the refrigerant liquid pipe, and the refrigerant liquid is vaporized and vaporized by the heat exchanger for heating. The refrigerant gas sent to the indoor unit can be effectively cooled and heated using separate heat exchangers during cooling and heating.
[0021]
The invention of claim 3 of the present invention, in claim 2, a check valve is provided for passing only the liquid refrigerant sent to the liquid refrigerant pipe from the auxiliary pump side between the auxiliary pump and the heat exchanger for heating Therefore, during the heating operation, the refrigerant liquid can be prevented from being sent to the auxiliary pump side, and the refrigerant liquid can be reliably sent to the heating heat exchanger.
[0022]
In the invention of claim 4 of the present invention, the cooling / heating switching valve is provided in series with the heat exchanger for heating in claim 2 or 3 , so that the cooling / heating switching valve is used for cooling during cooling. The refrigerant flows only in the heat exchanger, and the refrigerant can flow only in the heating heat exchanger during heating.
[0023]
Further, according to the fifth aspect of the present invention, in the second to fourth aspects, the auxiliary pump is driven when a predetermined amount or more of the refrigerant liquid is accumulated in the tank during the heating operation. Even if the refrigerant flows into the heat exchanger for cooling, it can be returned by the auxiliary pump.
[0024]
Moreover, since the invention of claim 6 of the present invention is provided with means for keeping the liquid flow rate from the auxiliary pump constant in any of claims 1 to 5, when the refrigerant liquid is sent by the auxiliary pump, The liquid feeding flow rate can be kept constant and stable liquid feeding can be performed.
[Brief description of the drawings]
FIG. 1 is a piping diagram showing an example of an embodiment of the present invention.
FIGS. 2A, 2B, and 2C are system diagrams showing means for keeping a liquid flow rate from the auxiliary pump same as the above. FIG.
FIG. 3 is a piping system diagram showing another example of the above.
FIG. 4 is a piping diagram showing another example of the above.
FIG. 5 is a piping system diagram showing another example of the above.
FIG. 6 is a piping system diagram showing a conventional example.
FIG. 7 is a piping diagram of the above conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Outdoor unit 2 Indoor unit 3 Refrigerant liquid piping 4 Refrigerant gas piping 5 Circulation pump 6 Cooling / heating switching valve 7 Heat exchanger 8 Tank 9 Auxiliary pump 12 Heat exchanger 13 Check valve 15 Cooling / heating switching valve
