JP4076753B2

JP4076753B2 - Air conditioner

Info

Publication number: JP4076753B2
Application number: JP2001329544A
Authority: JP
Inventors: 純一亀山; 智彦河西; 勝彦林田
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2001-10-26
Filing date: 2001-10-26
Publication date: 2008-04-16
Anticipated expiration: 2021-10-26
Also published as: JP2003130482A

Description

【０００１】
【発明の属する技術分野】
この発明は、空気調和装置、特に熱源機１台に対して複数台の室内機を接続する多室型ヒートポンプ空気調和装置で、各室内機毎に冷暖房を選択的に行なうことができ、冷房を行なう室内機と、暖房を行なう室内機とを同時に運転することができる空気調和装置に関するものである。
【０００２】
【従来の技術】
図１１は、例えば特開平４−３３５９６７号公報に示された従来の空気調和装置の全体構成を示す冷媒回路図である。この図において、Ａは熱源機、Ｂ、Ｃ、Ｄは後述するように互いに並列接続された複数台の室内機で、それぞれ同じ構成とされている。Ｅは熱源機Ａと室内機Ｂ、Ｃ、Ｄとを接続する中継機で、構成については後述する。
【０００３】
図１１において、熱源機Ａは以下に述べる各構成要素によって構成されている。即ち、１は圧縮機、２は圧縮機１に接続され、冷媒の流通方向を切り換える四方切換弁、３は熱源機側熱交換器、４は四方切換弁２と圧縮機１との間に接続されたアキュムレータ、３２は熱源機側熱交換器３と後述する第２の接続配管７との間に設けられた第３の逆止弁であり、熱源機側熱交換器３から第２の接続配管７の方向へのみ冷媒流通を許容する。３３は四方切換弁２と後述する第１の接続配管６との間に設けられた第４の逆止弁であり、第１の接続配管６から四方切換弁２の方向へのみ冷媒流通を許容する。３４は四方切換弁２と第２の接続配管７との間に設けられた第５の逆止弁であり、四方切換弁２から第２の接続配管７の方向へのみ冷媒流通を許容する。３５は熱源機側熱交換器３と第１の接続配管６との間に設けられた第６の逆止弁であり、第１の接続配管６から熱源機側熱交換器３の方向へのみ冷媒流通を許容する。
【０００４】
また、室内機Ｂ、Ｃ、Ｄは、それぞれ室内側熱交換器５と、各室内側熱交換器５に近接して室内側熱交換器５に直列接続された第１の流量制御装置９とで構成されている。なお、第１の流量制御装置９は、冷房時は室内側熱交換器５の出口側の過熱度により、暖房時は同じく出口側の過冷却度により開閉状態が制御されるようにされている。更に、中継機Ｅは四方切換弁２と接続された太い第１の接続配管６及び熱源機側熱交換器３と接続され、第１の接続配管６より細い第２の接続配管７によって熱源機Ａと接続され、室内機Ｂ、Ｃ、Ｄの室内側熱交換器５と接続された室内機側の第１の接続配管６ｂ、６ｃ、６ｄ及び室内機Ｂ、Ｃ、Ｄの第１の流量制御装置９に接続された室内機側の第２の接続配管７ｂ、７ｃ、７ｄによって各室内機Ｂ、Ｃ、Ｄと接続されると共に、以下に述べるような内部構成を有する。
【０００５】
即ち、１０は室内機側の第１の接続配管６ｂ、６ｃ、６ｄを、第１の接続配管６または第２の接続配管７に選択的に接続する第１の分岐部で、一端が室内機側の第１の接続配管６ｂ、６ｃ、６ｄにそれぞれ接続され、他端が一括接続されて第１の接続配管６に接続された３個の第１の弁装置８ａと、一端が室内機側の第１の接続配管６ｂ、６ｃ、６ｄにそれぞれ接続され、他端が一括接続されて第２の接続配管７に接続された３個の第２の弁装置８ｂとから構成され、第１の弁装置８ａを開路、第２の弁装置８ｂを閉路することにより、室内機側の第１の接続配管６ｂ、６ｃ、６ｄを第１の接続配管６に接続し、また、第１の弁装置８ａを閉路、第２の弁装置８ｂを開路することにより、室内機側の第１の接続配管６ｂ、６ｃ、６ｄを第２の接続配管７に接続するものである。
【０００６】
１１は室内機側の第２の接続配管７ｂ、７ｃ、７ｄの会合部１７Ａを有する第２の分岐部、１２は第２の接続配管７の途中に設けられた気液分離装置で、その気相部は、第２の接続配管７を経て第２の弁装置８ｂに接続され、その液相部は第２の分岐部１１に接続されている。１３は気液分離装置１２と第２の分岐部１１との間に接続された開閉自在な第２の流量制御装置、１４は第２の分岐部１１と上記第１の接続配管６を結ぶバイパス配管、１５はバイパス配管１４の途中に設けられた第３の流量制御装置、１６ｂ、１６ｃ、１６ｄは第２の分岐部１１内でバイパス配管１４の第３の流量制御装置１５の下流部分と各室内機側の第２の接続配管７ｂ、７ｃ、７ｄとの間でそれぞれ熱交換を行なう第３の熱交換部である。
【０００７】
１６ａはバイパス配管１４の第３の流量制御装置１５の下流で第３の熱交換部１６ｂ、１６ｃ、１６ｄの更に下流部分と各室内機側の第２の接続配管７ｂ、７ｃ、７ｄの会合部１７Ａとの間で熱交換を行なう第２の熱交換部、１９はバイパス配管１４の第２の熱交換部１６ａより更に下流部分と、気液分離装置１２及び第２の流量制御装置１３を接続する配管との間で熱交換を行なう第１の熱交換部、２７は第２の分岐部１１と第１の接続配管６との間に接続された開閉自在な第４の流量制御装置である。
中継機Ｅは上述した第１の分岐部１０、第２の分岐部１１、気液分離装置１２、第２、第３、第４の流量制御装置１３、１５、２７、第１、第２、第３の熱交換部１９、１６ａ、１６ｂ、１６ｃ、１６ｄ、及びバイパス配管１４等を内蔵するものである。
【０００８】
このように構成された従来の空気調和装置によって、大きく分けて３つの形態の運転が行なわれる。即ち、複数台の室内機の総てで冷房運転を行なう場合と、複数台の室内機の総てで暖房運転を行なう場合と、複数台の室内機のうち一部は冷房運転を行ない、他の一部は暖房運転を行なう場合（冷暖房同時運転）とである。
【０００９】
まず、図１２の運転動作状態を示す説明図にて、上述した運転の形態のうち冷房運転のみの場合について説明する。図１２に冷媒の流れを実線矢印で示すように、圧縮機１より吐出された高温高圧の冷媒ガスは四方切換弁２を通り、熱源機側熱交換器３で熱交換して凝縮された後、第３の逆止弁３２、第２の接続配管７を通り、中継機Ｅへ流入する。中継機Ｅへ流入した冷媒は気液分離装置１２、第２の流量制御装置１３の順に通り、第２の分岐部１１へ流入する。
第２の分岐部１１へ流入した冷媒は、会合部１７Ａで室内機側の第２の接続配管７ｂ、７ｃ、７ｄに分流すると共に、各室内機Ｂ、Ｃ、Ｄに流入し、各室内側熱交換器５の出口の過熱度により制御される第１の流量制御装置９により低圧まで減圧された後、室内側熱交換器５で室内空気と熱交換して蒸発しガス化され室内を冷房する。そして、ガス状態となった冷媒は、室内機側の第１の接続配管６ｂ、６ｃ、６ｄ、第１の分岐部１０の第１の弁装置８ａを通り、第１の接続配管６、第４の逆止弁３３、四方切換弁２、アキュムレータ４を経て圧縮機１に吸入される循環サイクルを構成し、冷房運転を行なう。この時、第１の弁装置８ａは開路、第２の弁装置８ｂは閉路されている。
【００１０】
また、この時、第１の接続配管６は低圧、第２の接続配管７は高圧のため必然的に第３の逆止弁３２、第４の逆止弁３３へ冷媒が流通する。
また、このサイクルの時、第２の流量制御装置１３を通過した冷媒の一部がバイパス配管１４へ入り、第３の流量制御装置１５で低圧まで減圧されて、第３の熱交換部１６ｂ、１６ｃ、１６ｄで各室内機側の第２の接続配管７ｂ、７ｃ、７ｄとの間で熱交換を行ない、更に、第２の熱交換部１６ａで第２の分岐部１１の各室内機側の第２の接続配管７ｂ、７ｃ、７ｄの会合部１７Ａとの間で熱交換を行ない、更にまた、第１の熱交換部１９で第２の流量制御装置１３に流入する冷媒との間で熱交換を行ない蒸発した冷媒は、第１の接続配管６へ入り、第４の逆止弁３３、四方切換弁２、アキュムレータ４を経て圧縮機１に吸入される。
一方、第１及び第２並びに第３の熱交換部１９、１６ａ、１６ｂ、１６ｃ、１６ｄで熱交換し、冷却されて過冷却度を十分につけられた上記第２の分岐部１１の冷媒は冷房しようとしている室内機Ｂ、Ｃ、Ｄへ流入する。
【００１１】
次に、図１２を用いて暖房運転のみの場合について説明する。この場合は、四方切換弁２が切り換えられ、冷媒の流れが図１２に破線矢印で示すようになる。即ち、圧縮機１より吐出された高温高圧の冷媒ガスは四方切換弁２を通り、第５の逆止弁３４、第２の接続配管７を通り、中継機Ｅへ流入する。中継機Ｅへ流入した冷媒は、気液分離装置１２、第２の接続配管７を経て第１の分岐部１０に流入する。第１の分岐部１０に流入した冷媒は、第２の弁装置８ｂ、室内機側の第１の接続配管６ｂ、６ｃ、６ｄを通り、各室内機Ｂ、Ｃ、Ｄに流入し、室内側熱交換器５で室内空気と熱交換して凝縮液化し、室内を暖房する。そして、液状態となった冷媒は、各室内側熱交換器５の出口の過冷却度により制御される第１の流量制御装置９を通り、室内機側の第２の接続配管７ｂ、７ｃ、７ｄから第２の分岐部１１に流入して会合部１７Ａで合流し、更に第４の流量制御装置２７を通り、第１の流量制御装置９または第４の流量制御装置２７のどちらか一方で低圧の気液二相状態まで減圧される。そして、低圧まで減圧された冷媒は、第１の接続配管６に至る。
【００１２】
また、室内機側の第２の接続配管７ｂ、７ｃ、７ｄから会合部１７Ａで合流した冷媒の一部は、バイパス配管１４に流入し、第３の流量制御装置１５で減圧された後、第３の熱交換部１６ｂ、１６ｃ、１６ｄ、第２の熱交換部１６ａ、第１の熱交換部１９を経て第１の接続配管６に至り、上述した第４の流量制御装置２７からの冷媒と合流し、第６の逆止弁３５、熱源機側熱交換器３に流入し熱交換して蒸発しガス状態となった冷媒は、四方切換弁２、アキュムレータ４を経て圧縮機１に吸入される循環サイクルを構成し、暖房運転を行なう。この時、第１の弁装置８ａは閉路、第２の弁装置８ｂは開路されている。また、第１の接続配管６は低圧、第２の接続配管７は高圧のため必然的に第５の逆止弁３４、第６の逆止弁３５へ冷媒が流通する。
【００１３】
【発明が解決しようとする課題】
従来の空気調和装置は以上のように構成され、室内機側への冷媒流路が常に流通した状態にあるため、室内機側で配管等の亀裂や配管接続部の緩みが生じた場合には、運転中あるいは停止中あるいはサーモＯＦＦ中に関わらず、冷媒回路内の冷媒が全て室内側に漏洩してしまい、それが小さな居住空間であった場合には、冷媒による窒息の危険性があるという問題点があった。
【００１４】
この発明は、このような問題点を解決するためになされたもので、室内機側で配管等の亀裂や配管接続部の緩みがあった場合でも、室内機側への冷媒の漏洩を防ぐことができる空気調和装置を提供することを目的とする。
【００１５】
【課題を解決するための手段】
この発明に係る空気調和装置は、圧縮機と、この圧縮機から吐出された冷媒の流路を切り換える四方切換弁と、この四方切換弁に接続された熱源機側熱交換器とを有する１台の熱源機、室内側熱交換器と、これに接続された流量制御装置とを有する複数台の室内機、及び上記熱源機と各室内機とを第１及び第２の接続配管を介して接続すると共に、上記各室内側熱交換器の一方の端部を上記第１及び第２の接続配管に切り換え可能に接続する弁装置を有する第１の分岐部と、上記各室内側熱交換器の他方の端部にそれぞれ接続された弁装置と、この弁装置にそれぞれ接続された逆止弁を介して上記各室内側熱交換器の他方の端部を上記第２の接続配管に接続し得るようにされた第２の分岐部とを有する中継機並びに上記室内機の流量制御装置と上記第１の分岐部の弁装置と上記各室内側熱交換器の他方の端部にそれぞれ接続された弁装置の開閉を制御する弁装置制御部を備え、上記弁装置制御部は外部信号受信部を経て与えられる冷媒回路の冷媒漏れを検知した検知信号によって制御されるものである。
【００１６】
この発明に係る空気調和装置は、また、第１の分岐部の弁装置が、各室内側熱交換器の一方の端部にそれぞれ並列的に接続された２つの弁を有し、一方の弁は第１の接続配管に接続され、他方の弁は第２の接続配管に接続されているものである。
【００２０】
この発明に係る空気調和装置は、また、室内機が運転を停止あるいはサーモＯＦＦする時、弁装置制御部は、冷媒の流通方向に対して上流側に位置する弁装置を閉路し、所定時間経過後に下流側に位置する弁装置を閉路するようにしたものである。
【００２１】
この発明に係る空気調和装置は、また、冷房運転時における運転停止あるいはサーモＯＦＦ時には、上流側に位置する弁装置が、各室内側熱交換器の他方の端部にそれぞれ接続された弁装置であり、下流側に位置する弁装置が、流量制御装置及び第１の分岐部の弁装置とされるものである。
【００２２】
この発明に係る空気調和装置は、また、暖房運転時における運転停止あるいはサーモＯＦＦ時には、上流側に位置する弁装置が、第１の分岐部の弁装置であり、下流側に位置する弁装置が、各室内側熱交換器の他方の端部にそれぞれ接続された流量制御装置及び弁装置とされるものである。
【００２３】
【発明の実施の形態】
実施の形態１．
以下、この発明の実施の形態１を図にもとづいて詳細に説明する。
図１は、実施の形態１による空気調和装置の全体構成を示す冷媒回路図である。なお、図１では熱源機１台に室内機３台、中継機１台を接続した場合について説明するが、４台以上の室内機、及び２台以上の中継機を接続した場合でも同様の効果が期待できることは云うまでもない。
【００２４】
図１において、Ａは熱源機、Ｂ、Ｃ、Ｄは後述するように互いに並列接続された室内機で、それぞれ同じ構成とされている。Ｅは熱源機Ａと室内機Ｂ、Ｃ、Ｄとを接続する中継機で、構成については後述する。
熱源機Ａは以下に述べる各構成要素によって構成されている。即ち、１は圧縮機、２は圧縮機１に接続され、冷媒の流通方向を切り換える四方切換弁、３は熱源機側熱交換器、４は四方切換弁２と圧縮機１との間に接続されたアキュムレータ、３２は熱源機側熱交換器３と後述する第２の接続配管７との間に設けられた第３の逆止弁であり、熱源機側熱交換器３から第２の接続配管７の方向へのみ冷媒流通を許容する。
３３は四方切換弁２と後述する第１の接続配管６との間に設けられた第４の逆止弁であり、第１の接続配管６から四方切換弁２の方向へのみ冷媒流通を許容する。３４は四方切換弁２と第２の接続配管７との間に設けられた第５の逆止弁であり、四方切換弁２から第２の接続配管７の方向へのみ冷媒流通を許容する。３５は熱源機側熱交換器３と第１の接続配管６との間に設けられた第６の逆止弁であり、第１の接続配管６から熱源機側熱交換器３の方向へのみ冷媒流通を許容する。
【００２５】
また、室内機Ｂ、Ｃ、Ｄは、それぞれ室内側熱交換器５と、各室内側熱交換器５に近接して室内側熱交換器５に直列接続された第１の流量制御装置９とで構成されている。なお、第１の流量制御装置９は、冷房時は室内側熱交換器５の出口側の過熱度により、暖房時は同じく出口側の過冷却度により開閉状態が制御されるようにされている。更に、中継機Ｅは四方切換弁２と接続された太い第１の接続配管６及び熱源機側熱交換器３と接続され、第１の接続配管６より細い第２の接続配管７によって熱源機Ａと接続され、室内機Ｂ、Ｃ、Ｄの室内側熱交換器５と接続された室内機側の第１の接続配管６ｂ、６ｃ、６ｄ及び室内機Ｂ、Ｃ、Ｄの第１の流量制御装置９に接続された室内機側の第２の接続配管７ｂ、７ｃ、７ｄによって各室内機Ｂ、Ｃ、Ｄと接続されると共に、以下に述べるような内部構成を有する。
【００２６】
即ち、１０は室内機側の第１の接続配管６ｂ、６ｃ、６ｄを、第１の接続配管６または第２の接続配管７に切り換え可能に接続する第１の分岐部で、一端が室内機側の第１の接続配管６ｂ、６ｃ、６ｄにそれぞれ接続され、他端が一括接続されて第１の接続配管６に接続された３個の第１の弁装置８ａと、一端が室内機側の第１の接続配管６ｂ、６ｃ、６ｄにそれぞれ接続され、他端が一括接続されて第２の接続配管７に接続された３個の第２の弁装置８ｂとから構成され、第１の弁装置８ａを開路、第２の弁装置８ｂを閉路することにより、室内機側の第１の接続配管６ｂ、６ｃ、６ｄを第１の接続配管６に接続し、また、第１の弁装置８ａを閉路、第２の弁装置８ｂを開路することにより、室内機側の第１の接続配管６ｂ、６ｃ、６ｄを第２の接続配管７に接続するものである。
【００２７】
１１は室内機側の第２の接続配管７ｂ、７ｃ、７ｄにそれぞれ接続された第３の弁装置２０に対してそれぞれ逆並列関係に一端が接続された第１の逆止弁１７及び第２の逆止弁１８と、第１の逆止弁１７の各他端を一括接続した会合部１７Ａと、第２の逆止弁１８の各他端を一括接続した会合部１８Ａとを有する第２の分岐部、１２は第２の接続配管７の途中に設けられた気液分離装置で、その気相部は、第２の接続配管７を経て第１の分岐部１０の第２の弁装置８ｂに接続され、その液相部は第２の分岐部１１に接続されている。１３は気液分離装置１２と第２の分岐部１１との間に接続された開閉自在な第２の流量制御装置、１４は第２の分岐部１１の会合部１８Ａと上記第１の接続配管６を結ぶバイパス配管、１５はバイパス配管１４の途中に設けられた第３の流量制御装置、１６はバイパス配管１４の第３の流量制御装置１５の下流部分と第２の流量制御装置１３から第２の分岐部１１の会合部１８Ａに至る配管との間で熱交換を行なう第２の熱交換部、１９はバイパス配管１４の第２の熱交換部１６の下流部分と、気液分離装置１２及び第２の流量制御装置１３を接続する配管との間で熱交換を行なう第１の熱交換部、２１は上記第１、第２、第３の弁装置８ａ、８ｂ、２０の開閉を制御する弁装置制御部、また、４５は第２の流量制御装置１３と気液分離装置１２とを接続する配管に取り付けた第１の圧力検出器、４６は第２の流量制御装置１３と第２の分岐部１１とを接続する配管に取り付けた第２の圧力検出器である。
【００２８】
このように構成された実施の形態１の空気調和装置によって、上述したように大きく分けて３つの形態の運転が行なわれる。即ち、複数の室内機の総てで冷房運転を行なう場合と、複数の室内機の総てで暖房運転を行なう場合と、複数の室内機のうち一部は冷房運転を行ない、他の一部は暖房運転を行なう場合（冷暖房同時運転）とである。更に、冷暖房同時運転については、２つの形態の運転が行なわれる。即ち、複数の室内機のうち大部分の室内機が暖房運転を行なう場合（暖房主体運転）と、複数の室内機のうち大部分の室内機が冷房運転を行なう場合（冷房主体運転）とである。
【００２９】
まず、図２を用いて冷房運転のみの場合について説明する。即ち、図２に冷媒の流れを実線矢印で示すように、圧縮機１より吐出された高温高圧の冷媒ガスは四方切換弁２を通り、熱源機側熱交換器３で熱交換して凝縮された後、第３の逆止弁３２、第２の接続配管７を通り、中継機Ｅへ流入する。
中継機Ｅへ流入した冷媒は気液分離装置１２、第２の流量制御装置１３の順に通り、第２の分岐部１１へ流入する。第２の分岐部１１へ流入した冷媒は、会合部１７Ａ、第１の逆止弁１７、第３の弁装置２０、室内機側の第２の接続配管７ｂ、７ｃ、７ｄを通り、各室内機Ｂ、Ｃ、Ｄに流入し、各室内側熱交換器５の出口の過熱度により制御される第１の流量制御装置９により低圧まで減圧されて室内側熱交換器５で室内空気と熱交換して蒸発しガス化され室内を冷房する。
そして、ガス状態となった冷媒は、室内機側の第１の接続配管６ｂ、６ｃ、６ｄ、第１の分岐部１０の第１の弁装置８ａを通り、第１の接続配管６、第４の逆止弁３３、四方切換弁２、アキュムレータ４を経て圧縮機１に吸入される循環サイクルを構成し、冷房運転を行なう。この時、第１の弁装置８ａは開路、第２の弁装置８ｂは閉路、第３の弁装置２０は開路されている。
【００３０】
また、第１の接続配管６は低圧、第２の接続配管７は高圧のため必然的に第３の逆止弁３２、第４の逆止弁３３へ冷媒が流通する。
更に、このサイクルの時、第２の流量制御装置１３を通過した冷媒の一部が第２の熱交換部１６及び第３の流量制御装置１５を経てバイパス配管１４へ入り、第３の流量制御装置１５で低圧まで減圧されて、第２の熱交換部１６で第２の分岐部１１に流入する冷媒との間で熱交換を行ない、また、第１の熱交換部１９で第２の流量制御装置１３に流入する冷媒との間で熱交換を行ない蒸発した冷媒は、第１の接続配管６へ入り、第４の逆止弁３３、四方切換弁２、アキュムレータ４を経て圧縮機１に吸入される。一方、第１の熱交換部１９で熱交換し、冷却され過冷却度を十分につけられた上記第２の分岐部１１の冷媒は、第１の逆止弁１７、室内機側の第２の接続配管７ｂ、７ｃ、７ｄを経由して冷房しようとしている室内機Ｂ、Ｃ、Ｄへ流入する。
【００３１】
次に、図２を用いて暖房運転のみの場合について説明する。この場合は、四方切換弁２が切り換えられ、冷媒の流れが図２に破線矢印で示すようになる。即ち、圧縮機１より吐出された高温高圧の冷媒ガスは四方切換弁２を通り、第５の逆止弁３４、第２の接続配管７を通り、中継機Ｅへ流入する。中継機Ｅへ流入した冷媒は気液分離装置１２、第２の接続配管７を経て第１の分岐部１０に流入する。第１の分岐部１０に流入した冷媒は、第２の弁装置８ｂ、室内機側の第１の接続配管６ｂ、６ｃ、６ｄを通り、各室内機Ｂ、Ｃ、Ｄに流入し、室内空気と熱交換して凝縮液化し、室内を暖房する。
【００３２】
そして、液状態となった冷媒は、各室内側熱交換器５の出口の過冷却度により制御される第１の流量制御装置９を通り、室内機側の第２の接続配管７ｂ、７ｃ、７ｄから第３の弁装置２０を経て第２の分岐部１１に流入し、第２の逆止弁１８を通った後、会合部１８Ａで合流し、ここから第３の流量制御装置１５に流入して低圧の気液二相状態まで減圧される。低圧まで減圧された冷媒は、バイパス配管１４、第２の熱交換部１６、第１の熱交換部１９を経た後、第１の接続配管６を通り、第６の逆止弁３５、熱源機側熱交換器３に流入し熱交換して蒸発しガス状態となった冷媒は、四方切換弁２、アキュムレータ４を経て圧縮機１に吸入される循環サイクルを構成し、暖房運転を行なう。この時、第１の弁装置８ａは閉路、第２の弁装置８ｂは開路、第３の弁装置２０は開路されている。
また、第１の接続配管６は低圧、第２の接続配管７は高圧のため必然的に第５の逆止弁３４、第６の逆止弁３５へ冷媒が流通する。
【００３３】
次に、冷暖房同時運転における暖房主体の場合について図３を用いて説明する。ここでは、室内機Ｂ、Ｃの２台が暖房、室内機Ｄの１台が冷房しようとしている場合について説明する。即ち、図３に冷媒の流れを実線矢印で示すように、圧縮機１より吐出された高温高圧の冷媒ガスは四方切換弁２、第５の逆止弁３４、第２の接続配管７を通り、中継機Ｅに流入する。中継機Ｅに流入した冷媒は気液分離装置１２、第２の接続配管７を経て第１の分岐部１０に流入する。
第１の分岐部１０へ流入した冷媒は、室内機Ｂ、Ｃに接続された第２の弁装置８ｂ、室内機側の第１の接続配管６ｂ、６ｃの順に通り、暖房しようとしている室内機Ｂ、Ｃに流入し、室内側熱交換器５で室内空気と熱交換して凝縮液化し、室内を暖房する。そして、液状態となった冷媒は、室内側熱交換器５の出口の過冷却度により制御され、ほぼ全開状態の第１の流量制御装置９を通り少し減圧されて高圧と低圧の中間の圧力（中間圧）になり、室内機側の第２の接続配管７ｂ、７ｃから第３の弁装置２０、第２の分岐部１１の第２の逆止弁１８を通り会合部１８Ａで合流する。
【００３４】
冷房しようとしている室内機Ｄへの冷媒の流れは、中継機Ｅの第２の分岐部１１の会合部１８Ａで合流した冷媒の一部が矢印Ｐ及びＱのように第２の熱交換部１６を経て第２の分岐部１１の会合部１７Ａに至り、室内機Ｄに接続された第１の逆止弁１７、第３の弁装置２０、室内機側の第２の接続配管７ｄを通り、室内側熱交換器５の出口の過熱度により制御される第１の流量制御装置９により減圧された後に室内機Ｄの室内側熱交換器５に入り熱交換して蒸発しガス状態となって室内を冷房し、第１の分岐部１０の室内機Ｄに接続された第１の弁装置８ａを介して第１の接続配管６に流入する。
一方、室内機Ｂ、Ｃから中継機Ｅの第２の分岐部１１の会合部１８Ａに流入した室内機Ｂ、Ｃの暖房用の冷媒の他の一部は、第２の接続配管７の高圧と第２の分岐部１１の中間圧との差を一定にするように制御される開閉自在な第３の流量制御装置１５を通ってバイパス配管１４に流入し、上述のように第１の接続配管６に至るため、ここで室内機Ｄを冷房した冷媒と合流して太い第１の接続配管６に流入し、第６の逆止弁３５、熱源機側熱交換器３に流入し熱交換して蒸発しガス状態となった冷媒は、四方切換弁２、アキュムレータ４を経て圧縮機１に吸入される循環サイクルを構成し、暖房主体運転を行なう。
【００３５】
この時、暖房しようとしている室内機Ｂ，Ｃに接続されている第１の弁装置８ａは閉路、第２の弁装置８ｂは開路、第３の弁装置２０は開路され、冷房しようとしている室内機Ｄに接続されている第１の弁装置８ａは開路、第２の弁装置８ｂは閉路、第３の弁装置２０は開路されている。また、第１の接続配管６は低圧、第２の接続配管７は高圧のため必然的に第５の逆止弁３４、第６の逆止弁３５へ冷媒が流通する。
【００３６】
また、このサイクルの時、バイパス配管１４へ入った冷媒は、第３の流量制御装置１５で低圧まで減圧されて、第２の熱交換部１６で第２の分岐部１１へ流入する冷媒との間で熱交換を行ない、更に第１の熱交換部１９で第２の流量制御装置１３へ流入する冷媒との間で熱交換を行ない蒸発した冷媒は、第１の接続配管６へ入り、第６の逆止弁３５を経て、熱源機側熱交換器３に流入し熱交換して蒸発しガス状態となる。そして、この冷媒は四方切換弁２、アキュムレータ４を経て圧縮機１に吸入される。一方、第１及び第２の熱交換部１９、１６で熱交換し冷却され過冷却度を十分につけられた冷媒は、上述のように、冷房しようとしている室内機Ｄへ流入する。
【００３７】
次に、冷暖房同時運転における冷房主体の場合について図４を用いて説明する。ここでは、室内機Ｂ、Ｃの２台が冷房、室内機Ｄの１台が暖房しようとしている場合について説明する。即ち、図４に冷媒の流れを実線矢印で示すように、圧縮機１より吐出された高温高圧の冷媒ガスは四方切換弁２を通り、熱源機側熱交換器３で任意量熱交換して気液２相の高温高圧冷媒となり、第３の逆止弁３２、第２の接続配管７を通り、中継機Ｅに流入する。中継機Ｅに流入した冷媒は気液分離装置１２へ送られ、ここで、ガス冷媒と液冷媒に分離され、分離されたガス冷媒は、第２の接続配管７を経て中継機Ｅの第１の分岐部１０の第２の弁装置８ｂ、室内機側の第１の接続配管６ｄの順に通り、暖房しようとしている室内機Ｄに流入し、室内側熱交換器５で室内空気と熱交換して凝縮液化し、室内を暖房する。
【００３８】
更に、室内側熱交換器５の出口の過冷却度により制御されほぼ全開状態の第１の流量制御装置９を通り少し減圧されて、高圧と低圧の中間の圧力（中間圧）となり、室内機側の第２の接続配管７ｄを経て第３の弁装置２０、第２の分岐部１１の第２の逆止弁１８を通り会合部１８Ａから矢印で示すようにバイパス配管１４に流入し、第３の流量制御装置１５で低圧まで減圧されて、第２の熱交換部１６で第２の分岐部１１に流入する冷媒との間で熱交換を行ない、また、第１の熱交換部１９で第２の流量制御装置１３へ流入する冷媒との間で熱交換を行ない蒸発した冷媒は、第１の接続配管６に至る。一方、中継器Ｅの気液分離装置１２で分離された残りの液冷媒は、第１の熱交換部１９で熱交換して冷却され過冷却度を十分につけた後、高圧と中間圧の差を一定にするように制御される第２の流量制御装置１３を通って矢印で示すように、第２の分岐部１１の会合部１７Ａに流入する。
【００３９】
冷房しようとしている室内機Ｂ、Ｃへの冷媒の流れは、中継機Ｅの第２の分岐部１１の会合部１７Ａから室内機Ｂ、Ｃに接続された第１の逆止弁１７、第３の弁装置２０、室内機側の第２の接続配管７ｂ、７ｃを通り、各室内機Ｂ、Ｃに流入する。そして、この冷媒は、室内機Ｂ、Ｃの室内側熱交換器５の出口の過熱度により制御される第１の流量制御装置９により低圧まで減圧されて室内側熱交換器５で室内空気と熱交換して蒸発しガス化され室内を冷房する。そして、ガス状態となった冷媒は、室内機側の第１の接続配管６ｂ、６ｃ、第１の分岐部１０の第１の弁装置８ａを経て第１の接続配管６へ流入し、バイパス配管１４を経て第１の接続配管６に流入する上述の室内機Ｄの暖房用冷媒と合流した後、第４の逆止弁３３、四方切換弁２、アキュムレータ４を経て圧縮機１に吸入される循環サイクルを構成し、冷房主体運転を行なう。
【００４０】
この時、冷房しようとしている室内機Ｂ，Ｃに接続されている第１の弁装置８ａは開路、第２の弁装置８ｂは閉路、第３の弁装置２０は開路され、暖房しようとしている室内機Ｄに接続されている第１の弁装置８ａは閉路、第２の弁装置８ｂは開路、第３の弁装置２０は開路されている。また、第１の接続配管６は低圧、第２の接続配管７は高圧のため必然的に第３の逆止弁３２、第４の逆止弁３３へ冷媒が流通する。
【００４１】
次に、室内機が運転状態から停止あるいはサーモＯＦＦした場合の制御動作について説明する。図５は、室内機が冷房運転の場合の制御動作を示すフローチャートである。ステップＳ５０では室内機が冷房運転中か冷房運転中でないかを判定する。冷房運転中の場合はステップＳ５１へ進み、冷房運転中でない場合はステップＳ５０に戻る。ステップＳ５１では室内機が停止したか停止していないかを判定する。停止した場合にはステップＳ５３に進み、停止していない場合はステップＳ５２へ進む。ステップＳ５２では室内機がサーモＯＦＦしたかサーモＯＦＦしていないかを判定する。サーモＯＦＦした場合にはステップＳ５３へ進み、サーモＯＦＦしていない場合はステップＳ５１に戻る。ステップＳ５３では第１の弁装置８ａ及び第３の弁装置２０を閉としてステップＳ５０へ戻る。
【００４２】
また、図６は、室内機が暖房運転の場合の制御動作を示すフローチャートである。ステップＳ６０では室内機が暖房運転中か暖房運転中でないかを判定する。暖房運転中の場合はステップＳ６１へ進み、暖房運転中でない場合はステップＳ６０に戻る。ステップＳ６１では室内機が停止したか停止していないかを判定する。停止した場合にはステップＳ６３に進み、停止していない場合はステップＳ６２へ進む。ステップＳ６２では室内機がサーモＯＦＦしたかサーモＯＦＦしていないかを判定する。サーモＯＦＦした場合にはステップＳ６３へ進み、サーモＯＦＦしていない場合はステップＳ６１に戻る。ステップＳ６３では第２の弁装置８ｂ及び第３の弁装置２０を閉としてステップＳ６０へ戻る。
【００４３】
以上のように室内機が冷房運転から停止あるいはサーモＯＦＦした場合には、当該室内機に接続している第１、第３の弁装置８ａ、２０を閉として中継機Ｅと室内機との間の冷媒の流通経路を遮断し、室内機が暖房運転から停止あるいはサーモＯＦＦした場合には、当該室内機に接続している第２、第３の弁装置８ｂ、２０を閉として中継機Ｅと室内機との間の冷媒の流通経路を遮断するため、室内機側の配管に亀裂あるいは配管接続部分に緩みがあった場合でも、冷媒回路内の冷媒が多量に室内側に漏洩するのを防止することができる。
【００４４】
実施の形態２．
次に、この発明の実施の形態２を図にもとづいて詳細に説明する。
図７は、実施の形態２の全体構成を示す冷媒回路図である。この図において、図１と同一または相当部分には同一符号を付して説明を省略する。図１と異なる点は、弁装置制御部２１を外部信号によって駆動し得るようにした点である。即ち図７において、２２は外部信号を受信して弁装置制御部２１を駆動する外部信号受信部である。また、冷房運転、暖房運転、冷暖房同時運転（冷房主体運転及び暖房主体運転）時における冷媒の流れは、上述した実施の形態１と同じであるため説明は省略する。
【００４５】
次に、実施の形態２における第１、第２、第３の弁装置８ａ、８ｂ、２０の制御動作について説明する。図８は、第１、第２、第３の弁装置８ａ、８ｂ、２０の制御動作を示すフローチャートである。ステップＳ８０では室内機が冷房運転中であるか冷房運転中でないかを判定する。冷房運転中であればステップＳ８２に進み、冷房運転中でない場合はステップＳ８１へ進む。ステップＳ８１では室内機が暖房運転中であるか暖房運転中でないかを判定する。暖房運転中である場合はステップＳ８３へ進み、暖房運転中でない場合はステップＳ８０へ戻る。
ステップＳ８２では外部信号を受信したか受信していないかを判定する。
受信した場合はステップＳ８４へ進み、受信していない場合はステップＳ８０へ戻る。ステップＳ８４では第１、第３の弁装置８ａ、２０を閉としてステップＳ８０へ戻る。一方、ステップＳ８３では外部信号を受信したか受信していないかを判定する。受信した場合はステップＳ８５へ進み、受信していない場合はステップＳ８０へ戻る。ステップＳ８５では第２、第３の弁装置８ｂ、２０を閉としてステップＳ８０へ戻る。
【００４６】
以上のように室内機が冷房運転中に外部信号受信部２２が外部信号（例えば、冷媒センサーによる冷媒漏れ検知信号等）を受信した場合には、弁装置制御部２１を動作させ、当該室内機に接続している第１、第３の弁装置８ａ、２０を閉とすることによって、冷房運転中に冷媒漏れが検出された場合でも室内側への冷媒の流通を遮断でき、室内側への冷媒漏洩を最小限にすることができる。
また、室内機が暖房運転中に外部信号受信部２２が外部信号（例えば、冷媒センサーによる冷媒漏れ検知信号等）を受信した場合には、同様に弁装置制御部２１を動作させ、当該室内機に接続している第２、第３の弁装置８ｂ、２０を閉とすることによって、暖房運転中に冷媒漏れが検出された場合でも室内側への冷媒の流通を遮断でき、室内側への冷媒漏洩を最小限にすることができる。
【００４７】
実施の形態３．
次に、この発明の実施の形態３について詳細に説明する。実施の形態３の全体構成図及び冷房運転、暖房運転、冷暖房同時運転（冷房主体運転及び暖房主体運転）時における冷媒の流れは、図１と同じであるため図１を流用して説明を省略する。図１と異なる点は、室内機の冷房運転を停止あるいはサーモＯＦＦする時、冷媒の流通方向に対して上流側に位置する弁装置を閉路し、所定時間経過後に下流側に位置する弁装置を閉路するようにした点である。
【００４８】
次に、実施の形態３における第１、第２、第３の弁装置８ａ、８ｂ、２０の制御動作を図９のフローチャートを用いて説明する。
ステップＳ９０では室内機が冷房運転中であるか冷房運転中でないかを判定する。冷房運転中であればステップＳ９１へ進み、冷房運転中でない場合はステップＳ９０へ戻る。ステップＳ９１では室内機が停止したか停止していないかを判定する。停止した場合にはステップＳ９３へ進み、停止していない場合にはステップＳ９２へ進む。ステップＳ９２では室内機がサーモＯＦＦしたかサーモＯＦＦしていないかを判定する。サーモＯＦＦした場合にはステップＳ９３へ進み、サーモＯＦＦしていない場合はステップＳ９１へ戻る。ステップＳ９３では第３の弁装置２０を閉としてステップＳ９４へ進む。ステップＳ９４では第３の弁装置２０を閉路した後の経過時間Ｔがあらかじめ設定された冷房遅延時間Ｔ０を経過しているか経過していないかを判定する。経過している場合にはステップＳ９５へ進み、経過していない場合はステップＳ９４へ戻る。ステップＳ９５では第１の流量制御装置９を閉として、ステップＳ９６へ進む。ステップＳ９６では第１の弁装置８ａを閉としてステップＳ９０へ戻る。
【００４９】
以上のように冷房している室内機が停止あるいはサーモＯＦＦする場合には、上流側である第３の弁装置２０を最初に閉とし、タイマ機能によりあらかじめ設定された経過時間Ｔ０を経過した後、下流側にある第１の流量制御装置９、第１の弁装置８ａを順次閉とすることによって、室内機側へ冷媒が滞留することなく冷媒を中継機Ｅあるいは熱源機Ａに回収することができる。このため、室内機側の配管に亀裂あるいは配管接続部分に緩みがあった場合でも、冷媒回路内の冷媒が室内側に漏洩するのを防止することができる。
【００５０】
実施の形態４．
次に、この発明の実施の形態４について詳細に説明する。実施の形態４の全体構成図及び冷房運転、暖房運転、冷暖房同時運転（冷房主体運転及び暖房主体運転）時における冷媒の流れは、図１と同じであるため図１を流用して説明を省略する。図１と異なる点は、室内機の暖房運転を停止あるいはサーモＯＦＦする時、冷媒の流通方向に対して上流側に位置する弁装置を閉路し、所定時間経過後に下流側に位置する弁装置を閉路するようにした点である。
【００５１】
次に、実施の形態４における第１、第２、第３の弁装置８ａ、８ｂ、２０の制御動作を図１０のフローチャートを用いて説明する。
ステップＳ１００では室内機が暖房運転中であるか暖房運転中でないかを判定する。暖房運転中であればステップＳ１０１へ進み、暖房運転中でない場合はステップＳ１００へ戻る。ステップＳ１０１では室内機が停止したか停止していないかを判定する。停止した場合にはステップＳ１０３へ進み、停止していない場合にはステップＳ１０２へ進む。ステップＳ１０２では室内機がサーモＯＦＦしたかサーモＯＦＦしていないかを判定する。サーモＯＦＦした場合にはステップＳ１０３へ進み、サーモＯＦＦしていない場合はステップＳ１０１へ戻る。
ステップＳ１０３では第２の弁装置８ｂを閉としてステップＳ１０４へ進む。ステップＳ１０４では第２の弁装置８ｂを閉路した後の経過時間Ｔがあらかじめ設定された暖房遅延時間Ｔ１を経過しているか経過していないかを判定する。
経過している場合にはステップＳ１０５へ進み、経過していない場合はステップＳ１０４へ戻る。ステップＳ１０５では第１の流量制御装置９を閉として、ステップＳ１０６へ進む。ステップＳ１０６では第３の弁装置２０を閉としてステップＳ１００へ戻る。
【００５２】
以上のように暖房している室内機が停止あるいはサーモＯＦＦする場合には、上流側である第２の弁装置８ｂを最初に閉とし、タイマ機能によりあらかじめ設定された経過時間Ｔ１を経過した後、下流側にある第１の流量制御装置９、第３の弁装置２０を順次閉とすることによって、室内機側へ冷媒が滞留することなく冷媒を中継機Ｅあるいは熱源機Ａに回収することができる。このため、室内機側の配管に亀裂あるいは配管接続部分に緩みがあった場合でも、冷媒回路内の冷媒が室内側に漏洩するのを防止することができる。
【００５３】
【発明の効果】
この発明に係る空気調和装置は、圧縮機と、この圧縮機から吐出された冷媒の流路を切り換える四方切換弁と、この四方切換弁に接続された熱源機側熱交換器とを有する１台の熱源機、室内側熱交換器と、これに接続された流量制御装置とを有する複数台の室内機、及び熱源機と各室内機とを第１及び第２の接続配管を介して接続すると共に、各室内側熱交換器の一方の端部を第１及び第２の接続配管に切り換え可能に接続する弁装置を有する第１の分岐部と、各室内側熱交換器の他方の端部にそれぞれ接続された弁装置と、この弁装置にそれぞれ接続された逆止弁を介して各室内側熱交換器の他方の端部を第２の接続配管に接続し得るようにされた第２の分岐部とを有する中継機を備えたものであるため、室内機が冷房運転あるいは暖房運転から停止した場合に、中継機と室内機とを接続するガス側、液側両方の弁装置を閉路することができるので、室内機側の配管亀裂あるいは配管接続部に緩みがあった場合でも、室内機側へ多量の冷媒が漏洩するのを防止することができる。
【００５４】
この発明に係る空気調和装置は、また、弁装置制御部が、外部信号に応じた制御動作を行なうようにされたものであるため、室内機が冷房運転中あるいは暖房運転中の場合でも、例えば冷媒センサー等による冷媒漏れの検知信号を外部信号として受信することにより、弁装置制御部が中継機と室内機とを接続するガス側、液側両方の弁装置を閉路する結果、室内機側の配管亀裂あるいは配管接続部に緩みがあった場合でも、室内機側へ多量の冷媒が漏洩するのを防止することができる。
【００５５】
この発明に係る空気調和装置は、また、室内機の運転を停止あるいはサーモＯＦＦする時、弁装置制御部は、冷媒の流通方向に対して上流側に位置する弁装置を閉路し、所定時間経過後に下流側に位置する弁装置を閉路するようにしたものであるため、室内機が冷房運転から停止あるいはサーモＯＦＦした場合には、中継機と室内機とを接続する部分において、冷媒流通方向の入口側である液側の弁装置を最初に閉とし、タイマ機能等によりあらかじめ設定された一定時間経過後に室内機の流量制御装置、出口側であるガス側の弁装置を順次閉とする結果、室内機内へ冷媒が滞留することなく中継機あるいは熱源機に回収でき、室内機側の配管亀裂あるいは配管接続部に緩みがあった場合でも、室内機側へ冷媒が漏洩するのを防止することができる。
【００５６】
また、室内機が暖房運転から停止あるいはサーモＯＦＦした場合には、中継機と室内機とを接続する部分において、冷媒流通方向の入口側であるガス側の弁装置を最初に閉とし、タイマ機能等によりあらかじめ設定された一定時間経過後に室内機の流量制御装置、出口側である液側の弁装置を順次閉とする結果、室内機内へ冷媒が滞留することなく中継機あるいは熱源機に回収でき、室内機側の配管亀裂あるいは配管接続部に緩みがあった場合でも、室内機側へ冷媒が漏洩するのを防止することができる。
【図面の簡単な説明】
【図１】この発明の実施の形態１の全体構成を示す冷媒回路図である。
【図２】図１に示す空気調和装置の冷房又は暖房のみの運転動作状態を示す説明図である。
【図３】図１に示す空気調和装置の冷暖房同時運転で暖房主体の運転動作状態を示す説明図である。
【図４】図１に示す空気調和装置の冷暖房同時運転で冷房主体の運転動作状態を示す説明図である。
【図５】この発明の実施の形態１の冷房運転時における弁装置の制御動作を示すフローチャートである。
【図６】この発明の実施の形態１の暖房運転時における弁装置の制御動作を示すフローチャートである。
【図７】この発明の実施の形態２の全体構成を示す冷媒回路図である。
【図８】この発明の実施の形態２における弁装置の制御動作を示すフローチャートである。
【図９】この発明の実施の形態３における弁装置の制御動作を示すフローチャートである。
【図１０】この発明の実施の形態４における弁装置の制御動作を示すフローチャートである。
【図１１】従来の空気調和装置の全体構成を示す冷媒回路図である。
【図１２】図１１に示す空気調和装置の冷房または暖房のみの運転動作状態を示す説明図である。
【符号の説明】
１圧縮機、２四方切換弁、３熱源機側熱交換器、４アキュムレータ、５室内側熱交換器、６第１の接続配管、６ａ，６ｂ，６ｃ室内機側の第１の接続配管、７第２の接続配管、７ａ，７ｂ，７ｃ室内機側の第２の接続配管、８ａ第１の弁装置、８ｂ第２の弁装置、９第１の流量制御装置、１０第１の分岐部、１１第２の分岐部、１２気液分離装置、１３第２の流量制御装置、１４バイパス配管、１５第３の流量制御装置、１６第２の熱交換部、１７第１の逆止弁、１７Ａ，１８Ａ会合部、１８第２の逆止弁、１９第１の熱交換部、２０第３の弁装置、２１弁装置制御部、２２外部信号受信部、３２第３の逆止弁、３３第４の逆止弁、３４第５の逆止弁、３５第６の逆止弁、４５第１の圧力検出器、４６第２の圧力検出器、Ａ熱源機、Ｂ，Ｃ，Ｄ室内機、Ｅ中継機。[0001]
BACKGROUND OF THE INVENTION
The present invention is an air conditioner, particularly a multi-chamber heat pump air conditioner in which a plurality of indoor units are connected to one heat source unit, and can selectively perform cooling and heating for each indoor unit. The present invention relates to an air conditioner capable of simultaneously operating an indoor unit to be performed and an indoor unit to be heated.
[0002]
[Prior art]
FIG. 11 is a refrigerant circuit diagram showing the overall configuration of a conventional air conditioner disclosed in, for example, Japanese Patent Laid-Open No. 4-335967. In this figure, A is a heat source unit, B, C, and D are a plurality of indoor units connected in parallel to each other as will be described later, each having the same configuration. E is a relay that connects the heat source unit A and the indoor units B, C, and D. The configuration will be described later.
[0003]
In FIG. 11, the heat source machine A is comprised by each component described below. That is, 1 is a compressor, 2 is connected to the compressor 1, and a four-way switching valve for switching the refrigerant flow direction, 3 is a heat source side heat exchanger, and 4 is connected between the four-way switching valve 2 and the compressor 1. The accumulator 32 is a third check valve provided between the heat source device side heat exchanger 3 and a second connection pipe 7 to be described later. The refrigerant flow is allowed only in the direction of the pipe 7. Reference numeral 33 denotes a fourth check valve provided between the four-way switching valve 2 and a first connection pipe 6 which will be described later, and permits refrigerant flow only from the first connection pipe 6 to the four-way switching valve 2. To do. Reference numeral 34 denotes a fifth check valve provided between the four-way switching valve 2 and the second connection pipe 7, and allows the refrigerant to flow only from the four-way switching valve 2 to the second connection pipe 7. Reference numeral 35 denotes a sixth check valve provided between the heat source machine side heat exchanger 3 and the first connection pipe 6, and only from the first connection pipe 6 toward the heat source machine side heat exchanger 3. Allow refrigerant flow.
[0004]
Each of the indoor units B, C, and D includes an indoor heat exchanger 5 and a first flow rate controller 9 connected in series to the indoor heat exchanger 5 in proximity to each indoor heat exchanger 5. It consists of The first flow rate control device 9 is controlled to be opened and closed by the degree of superheat on the outlet side of the indoor heat exchanger 5 during cooling, and also by the degree of supercooling on the outlet side during heating. . Further, the relay machine E is connected to the thick first connection pipe 6 connected to the four-way switching valve 2 and the heat source machine side heat exchanger 3, and is connected to the heat source machine by the second connection pipe 7 narrower than the first connection pipe 6. First flow pipes 6b, 6c, 6d on the indoor unit side connected to A and connected to the indoor heat exchanger 5 of indoor units B, C, D and first flow rates of the indoor units B, C, D The indoor unit B is connected to the indoor units B, C, and D by the second connection pipes 7b, 7c, and 7d on the indoor unit side connected to the control device 9, and has an internal configuration as described below.
[0005]
That is, reference numeral 10 denotes a first branch portion that selectively connects the first connection pipes 6b, 6c, and 6d on the indoor unit side to the first connection pipe 6 or the second connection pipe 7, and one end is the indoor unit. Side first connection pipes 6b, 6c, 6d, the other end being collectively connected and the first connection pipe 6 being connected to the first connection pipe 6, one end being the indoor unit side Each of the first connection pipes 6b, 6c, 6d, and the other end of the first connection pipe 6b, 6c, 6d. By opening the valve device 8a and closing the second valve device 8b, the first connection pipes 6b, 6c, 6d on the indoor unit side are connected to the first connection pipe 6, and the first valve device By closing 8a and opening the second valve device 8b, the first connection pipes 6b, 6c and 6d on the indoor unit side are connected to the second It is intended to be connected to the connection pipe 7.
[0006]
Reference numeral 11 denotes a second branch portion having a meeting portion 17A of the second connection pipes 7b, 7c and 7d on the indoor unit side, and 12 denotes a gas-liquid separation device provided in the middle of the second connection pipe 7. The phase portion is connected to the second valve device 8 b via the second connection pipe 7, and the liquid phase portion is connected to the second branch portion 11. Reference numeral 13 denotes a second flow control device that can be freely opened and closed connected between the gas-liquid separator 12 and the second branch portion 11, and 14 is a bypass that connects the second branch portion 11 and the first connection pipe 6. Piping, 15 is a third flow control device provided in the middle of the bypass piping 14, and 16b, 16c, 16d are downstream portions of the third flow control device 15 of the bypass piping 14 in the second branch portion 11, and It is a 3rd heat exchange part which each heat-exchanges with 2nd connection piping 7b, 7c, 7d by the side of an indoor unit.
[0007]
16a is a downstream part of the third flow control device 15 of the bypass pipe 14 and a further downstream part of the third heat exchange parts 16b, 16c, 16d and a meeting part of the second connection pipes 7b, 7c, 7d on the indoor unit side. A second heat exchanging section 19 for exchanging heat with 17A, 19 connects the gas-liquid separator 12 and the second flow controller 13 further downstream of the second heat exchanging section 16a of the bypass pipe 14. A first heat exchanging unit 27 for exchanging heat with the piping to be connected, 27 is a fourth flow control device that can be freely opened and closed connected between the second branching unit 11 and the first connecting pipe 6. .
The relay machine E includes the first branching unit 10, the second branching unit 11, the gas-liquid separation device 12, the second, third, and fourth flow rate control devices 13, 15, 27, the first, the second, The third heat exchange unit 19, 16a, 16b, 16c, 16d, the bypass pipe 14 and the like are incorporated.
[0008]
By the conventional air conditioner configured as described above, three forms of operation are performed. That is, when performing a cooling operation with all of a plurality of indoor units, when performing a heating operation with all of a plurality of indoor units, some of the plurality of indoor units perform a cooling operation, and others A part of the case is when heating operation is performed (simultaneous cooling and heating operation).
[0009]
First, in the explanatory view showing the operation state of FIG. 12, the case of only the cooling operation among the above-described operation forms will be described. As shown by the solid line arrow in FIG. 12, the high-temperature and high-pressure refrigerant gas discharged from the compressor 1 passes through the four-way switching valve 2 and is condensed by exchanging heat in the heat source unit side heat exchanger 3. , Flows through the third check valve 32 and the second connection pipe 7 and flows into the relay E. The refrigerant that has flowed into the relay E passes through the gas-liquid separator 12 and the second flow rate controller 13 in this order, and then flows into the second branch portion 11.
The refrigerant that has flowed into the second branch portion 11 is branched into the second connection pipes 7b, 7c, and 7d on the indoor unit side at the meeting portion 17A, and flows into the indoor units B, C, and D, After the pressure is reduced to a low pressure by the first flow rate control device 9 controlled by the degree of superheat at the outlet of the heat exchanger 5, it is evaporated and gasified by exchanging heat with the indoor air in the indoor heat exchanger 5 to cool the room. To do. The refrigerant in the gas state passes through the first connection pipes 6b, 6c and 6d on the indoor unit side and the first valve device 8a of the first branching section 10, and passes through the first connection pipe 6 and the fourth connection pipe. The recirculation cycle which is sucked into the compressor 1 through the check valve 33, the four-way switching valve 2 and the accumulator 4 is constructed, and the cooling operation is performed. At this time, the first valve device 8a is open, and the second valve device 8b is closed.
[0010]
At this time, since the first connection pipe 6 is low pressure and the second connection pipe 7 is high pressure, the refrigerant inevitably flows to the third check valve 32 and the fourth check valve 33.
In addition, during this cycle, a part of the refrigerant that has passed through the second flow control device 13 enters the bypass pipe 14 and is decompressed to a low pressure by the third flow control device 15, and the third heat exchange unit 16 b, 16c and 16d perform heat exchange with the second connection pipes 7b, 7c and 7d on the side of each indoor unit, and further, the second heat exchanging part 16a on the side of each indoor unit of the second branch part 11 Heat is exchanged with the meeting part 17A of the second connection pipes 7b, 7c, 7d, and further, heat is exchanged with the refrigerant flowing into the second flow control device 13 at the first heat exchange part 19. The exchanged and evaporated refrigerant enters the first connection pipe 6 and is sucked into the compressor 1 through the fourth check valve 33, the four-way switching valve 2, and the accumulator 4.
On the other hand, the first and second and third heat exchanging units 19, 16a, 16b, 16c, and 16d exchange heat, and the refrigerant of the second branching unit 11 that has been cooled and sufficiently subcooled is cooled. It flows into the indoor units B, C, and D that are going to be used.
[0011]
Next, the case of only the heating operation will be described with reference to FIG. In this case, the four-way switching valve 2 is switched, and the refrigerant flow is as shown by broken line arrows in FIG. That is, the high-temperature and high-pressure refrigerant gas discharged from the compressor 1 passes through the four-way switching valve 2, passes through the fifth check valve 34 and the second connection pipe 7, and flows into the relay machine E. The refrigerant that has flowed into the relay machine E flows into the first branch portion 10 through the gas-liquid separator 12 and the second connection pipe 7. The refrigerant that has flowed into the first branch portion 10 passes through the second valve device 8b and the first connection pipes 6b, 6c, and 6d on the indoor unit side, flows into the indoor units B, C, and D, The heat exchanger 5 exchanges heat with room air to condense and heat the room. And the refrigerant | coolant which became the liquid state passes through the 1st flow control apparatus 9 controlled by the subcooling degree of the exit of each indoor side heat exchanger 5, 2nd connection piping 7b, 7c on the indoor unit side, 7d flows into the second branch part 11 and joins at the meeting part 17A, passes through the fourth flow rate control device 27, and either the first flow rate control device 9 or the fourth flow rate control device 27. The pressure is reduced to a low-pressure gas-liquid two-phase state. Then, the refrigerant depressurized to a low pressure reaches the first connection pipe 6.
[0012]
In addition, a part of the refrigerant merged at the meeting portion 17A from the second connection pipes 7b, 7c, 7d on the indoor unit side flows into the bypass pipe 14 and is decompressed by the third flow control device 15, 3 through the heat exchange units 16b, 16c, 16d, the second heat exchange unit 16a, and the first heat exchange unit 19 to the first connection pipe 6, and the refrigerant from the fourth flow control device 27 described above. The refrigerant that has joined and flows into the sixth check valve 35 and the heat source device side heat exchanger 3 and exchanges heat to evaporate into a gas state is sucked into the compressor 1 through the four-way switching valve 2 and the accumulator 4. The circulation cycle is configured and heating operation is performed. At this time, the first valve device 8a is closed and the second valve device 8b is opened. Further, since the first connection pipe 6 is low pressure and the second connection pipe 7 is high pressure, the refrigerant inevitably flows to the fifth check valve 34 and the sixth check valve 35.
[0013]
[Problems to be solved by the invention]
The conventional air conditioner is configured as described above, and the refrigerant flow path to the indoor unit side is always in a circulating state. Regardless of whether it is in operation, stopped or when the thermo is turned off, all the refrigerant in the refrigerant circuit leaks indoors, and if it is a small living space, there is a danger of suffocation by the refrigerant There was a problem.
[0014]
The present invention has been made to solve such problems, and prevents leakage of refrigerant to the indoor unit side even when there is a crack in the piping or loosening of the pipe connection part on the indoor unit side. An object of the present invention is to provide an air-conditioning apparatus capable of performing the above.
[0015]
[Means for Solving the Problems]
The air conditioner according to the present invention includes a compressor, a four-way switching valve that switches a flow path of refrigerant discharged from the compressor, and a heat source machine side heat exchanger that is connected to the four-way switching valve. A plurality of indoor units having a heat source unit, an indoor heat exchanger, and a flow control device connected thereto, and the heat source unit and each indoor unit are connected via first and second connection pipes. And a first branch portion having a valve device for switching one end of each indoor heat exchanger to the first and second connection pipes, and each indoor heat exchanger. The other end of each indoor heat exchanger can be connected to the second connection pipe via a valve device connected to the other end and a check valve connected to the valve device. And a second branch portion A relay device, a flow control device for the indoor unit, a valve device for the first branching unit, and a valve device control unit for controlling opening and closing of the valve device connected to the other end of each indoor heat exchanger. The valve device control unit is controlled by a detection signal that detects a refrigerant leak in the refrigerant circuit that is given through an external signal receiving unit. Is.
[0016]
In the air conditioner according to the present invention, the valve device of the first branch section has two valves respectively connected in parallel to one end portion of each indoor heat exchanger. Is connected to the first connection pipe, and the other valve is connected to the second connection pipe.
[0020]
In the air conditioner according to the present invention, when the indoor unit stops operating or thermo-OFF, the valve device control unit closes the valve device located upstream with respect to the refrigerant flow direction, and a predetermined time has elapsed. The valve device located downstream is closed later.
[0021]
The air conditioner according to the present invention is also a valve device in which a valve device located on the upstream side is connected to the other end of each indoor heat exchanger when the operation is stopped during the cooling operation or when the thermo is OFF. In addition, the valve device located on the downstream side is the flow control device and the valve device of the first branch portion.
[0022]
In the air conditioner according to the present invention, when the operation is stopped during the heating operation or when the thermo is turned off, the valve device located on the upstream side is the valve device of the first branch portion, and the valve device located on the downstream side is The flow control device and the valve device are respectively connected to the other end of each indoor heat exchanger.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below in detail with reference to the drawings.
FIG. 1 is a refrigerant circuit diagram illustrating the overall configuration of the air-conditioning apparatus according to Embodiment 1. In addition, although FIG. 1 demonstrates the case where three indoor units and one repeater are connected to one heat source unit, the same effect can be obtained when four or more indoor units and two or more repeaters are connected. Needless to say, you can expect.
[0024]
In FIG. 1, A is a heat source unit, B, C, and D are indoor units connected in parallel as will be described later, and each has the same configuration. E is a relay that connects the heat source unit A and the indoor units B, C, and D. The configuration will be described later.
The heat source machine A is comprised by each component described below. That is, 1 is a compressor, 2 is connected to the compressor 1, and a four-way switching valve for switching the refrigerant flow direction, 3 is a heat source side heat exchanger, and 4 is connected between the four-way switching valve 2 and the compressor 1. The accumulator 32 is a third check valve provided between the heat source device side heat exchanger 3 and a second connection pipe 7 to be described later. The refrigerant flow is allowed only in the direction of the pipe 7.
Reference numeral 33 denotes a fourth check valve provided between the four-way switching valve 2 and a first connection pipe 6 which will be described later, and permits refrigerant flow only from the first connection pipe 6 to the four-way switching valve 2. To do. Reference numeral 34 denotes a fifth check valve provided between the four-way switching valve 2 and the second connection pipe 7, and allows the refrigerant to flow only from the four-way switching valve 2 to the second connection pipe 7. Reference numeral 35 denotes a sixth check valve provided between the heat source machine side heat exchanger 3 and the first connection pipe 6, and only from the first connection pipe 6 toward the heat source machine side heat exchanger 3. Allow refrigerant flow.
[0025]
Each of the indoor units B, C, and D includes an indoor heat exchanger 5 and a first flow rate controller 9 connected in series to the indoor heat exchanger 5 in proximity to each indoor heat exchanger 5. It consists of The first flow rate control device 9 is controlled to be opened and closed by the degree of superheat on the outlet side of the indoor heat exchanger 5 during cooling, and also by the degree of supercooling on the outlet side during heating. . Further, the relay machine E is connected to the thick first connection pipe 6 connected to the four-way switching valve 2 and the heat source machine side heat exchanger 3, and is connected to the heat source machine by the second connection pipe 7 narrower than the first connection pipe 6. First flow pipes 6b, 6c, 6d on the indoor unit side connected to A and connected to the indoor heat exchanger 5 of indoor units B, C, D and first flow rates of the indoor units B, C, D The indoor unit B is connected to the indoor units B, C, and D by the second connection pipes 7b, 7c, and 7d on the indoor unit side connected to the control device 9, and has an internal configuration as described below.
[0026]
That is, reference numeral 10 denotes a first branch portion that connects the first connection pipes 6b, 6c, and 6d on the indoor unit side to the first connection pipe 6 or the second connection pipe 7 in a switchable manner, and one end is the indoor unit. Side first connection pipes 6b, 6c, 6d, the other end being collectively connected and the first connection pipe 6 being connected to the first connection pipe 6, one end being the indoor unit side Each of the first connection pipes 6b, 6c, 6d, and the other end of the first connection pipe 6b, 6c, 6d. By opening the valve device 8a and closing the second valve device 8b, the first connection pipes 6b, 6c, 6d on the indoor unit side are connected to the first connection pipe 6, and the first valve device By closing 8a and opening the second valve device 8b, the first connection pipes 6b, 6c and 6d on the indoor unit side are connected. It is intended to be connected to the second connection pipe 7.
[0027]
11 is a first check valve 17 and a second check valve 17 whose one ends are connected in an anti-parallel relationship to the third valve device 20 connected to the second connection pipes 7b, 7c, 7d on the indoor unit side, respectively. A second check valve 18, a meeting part 17 </ b> A in which the other ends of the first check valve 17 are connected together, and a meeting part 18 </ b> A in which the other ends of the second check valve 18 are connected together. 12 is a gas-liquid separation device provided in the middle of the second connection pipe 7, and the gas phase portion thereof passes through the second connection pipe 7 and is the second valve device of the first branch section 10. The liquid phase part is connected to the second branch part 11. Reference numeral 13 denotes a second flow control device that can be freely opened and closed connected between the gas-liquid separator 12 and the second branch portion 11, and 14 is a meeting portion 18 </ b> A of the second branch portion 11 and the first connection pipe. 6 is a third flow control device provided in the middle of the bypass pipe 14, and 16 is a downstream portion of the third flow control device 15 of the bypass pipe 14 and the second flow control device 13. A second heat exchanging part 19 for exchanging heat with the pipe reaching the meeting part 18 </ b> A of the second branch part 11, 19 is a downstream part of the second heat exchanging part 16 of the bypass pipe 14, and the gas-liquid separator 12. And a first heat exchanging part 21 for exchanging heat with the pipes connecting the second flow rate control device 13, controls the opening and closing of the first, second and third valve devices 8 a, 8 b, 20. A valve device control unit that performs the second flow rate control device 13 and a gas-liquid separator. The first pressure detector mounted on piping connecting the 2, 46 is a second pressure detector which is mounted on the pipe connecting the second flow controller 13 and a second branch portion 11.
[0028]
As described above, the air conditioner according to the first embodiment configured as described above is roughly divided into three modes of operation. That is, when performing a cooling operation with all of the plurality of indoor units, when performing a heating operation with all of the plurality of indoor units, some of the plurality of indoor units perform a cooling operation, and some others Is the case where heating operation is performed (simultaneous cooling and heating operation). Further, two types of operation are performed for the simultaneous cooling and heating operation. That is, when most of the indoor units among the plurality of indoor units perform the heating operation (heating main operation) and when most of the indoor units among the plurality of indoor units perform the cooling operation (cooling main operation). is there.
[0029]
First, the case of only the cooling operation will be described with reference to FIG. That is, as shown by the solid line arrow in FIG. 2, the high-temperature and high-pressure refrigerant gas discharged from the compressor 1 passes through the four-way switching valve 2 and is condensed by exchanging heat in the heat source unit side heat exchanger 3. After that, it passes through the third check valve 32 and the second connection pipe 7 and flows into the relay machine E.
The refrigerant that has flowed into the relay E passes through the gas-liquid separator 12 and the second flow rate controller 13 in this order, and then flows into the second branch portion 11. The refrigerant flowing into the second branch portion 11 passes through the meeting portion 17A, the first check valve 17, the third valve device 20, and the second connection pipes 7b, 7c, 7d on the indoor unit side, Flows into the machines B, C, and D, and is reduced to a low pressure by the first flow rate control device 9 controlled by the degree of superheat at the outlet of each indoor heat exchanger 5, and the indoor heat exchanger 5 It is exchanged and evaporated to gasify, and the room is cooled.
The refrigerant in the gas state passes through the first connection pipes 6b, 6c and 6d on the indoor unit side and the first valve device 8a of the first branching section 10, and passes through the first connection pipe 6 and the fourth connection pipe. The recirculation cycle which is sucked into the compressor 1 through the check valve 33, the four-way switching valve 2 and the accumulator 4 is constructed, and the cooling operation is performed. At this time, the first valve device 8a is opened, the second valve device 8b is closed, and the third valve device 20 is opened.
[0030]
In addition, since the first connection pipe 6 is low pressure and the second connection pipe 7 is high pressure, the refrigerant inevitably flows to the third check valve 32 and the fourth check valve 33.
Further, during this cycle, a part of the refrigerant that has passed through the second flow rate control device 13 enters the bypass pipe 14 via the second heat exchange unit 16 and the third flow rate control device 15, and the third flow rate control. The pressure is reduced to a low pressure by the device 15, heat exchange is performed with the refrigerant flowing into the second branch portion 11 by the second heat exchange unit 16, and a second flow rate is obtained by the first heat exchange unit 19. The evaporated refrigerant that exchanges heat with the refrigerant flowing into the control device 13 enters the first connection pipe 6, passes through the fourth check valve 33, the four-way switching valve 2, and the accumulator 4 to the compressor 1. Inhaled. On the other hand, the refrigerant of the second branch portion 11 that has been heat-exchanged by the first heat exchanging portion 19 and has been sufficiently cooled to have a sufficient degree of supercooling is the first check valve 17, the second on the indoor unit side. It flows into the indoor units B, C, and D that are going to be cooled through the connection pipes 7b, 7c, and 7d.
[0031]
Next, the case of only heating operation will be described with reference to FIG. In this case, the four-way switching valve 2 is switched, and the refrigerant flow is as shown by broken-line arrows in FIG. That is, the high-temperature and high-pressure refrigerant gas discharged from the compressor 1 passes through the four-way switching valve 2, passes through the fifth check valve 34 and the second connection pipe 7, and flows into the relay machine E. The refrigerant flowing into the relay machine E flows into the first branch portion 10 through the gas-liquid separator 12 and the second connection pipe 7. The refrigerant that has flowed into the first branching section 10 passes through the second valve device 8b and the first connection pipes 6b, 6c, and 6d on the indoor unit side, flows into the indoor units B, C, and D, and passes through the indoor air. Heat is exchanged with the liquid to condense and heat the room.
[0032]
And the refrigerant | coolant which became the liquid state passes through the 1st flow control apparatus 9 controlled by the subcooling degree of the exit of each indoor side heat exchanger 5, 2nd connection piping 7b, 7c on the indoor unit side, 7d flows through the third valve device 20 to the second branch portion 11, passes through the second check valve 18, and then merges at the meeting portion 18A. From here, it flows into the third flow control device 15 Thus, the pressure is reduced to a low-pressure gas-liquid two-phase state. The refrigerant depressurized to a low pressure passes through the first connection pipe 6 after passing through the bypass pipe 14, the second heat exchange section 16, and the first heat exchange section 19, and then the sixth check valve 35, the heat source machine. The refrigerant that flows into the side heat exchanger 3 and exchanges heat to evaporate into a gas state constitutes a circulation cycle that is sucked into the compressor 1 through the four-way switching valve 2 and the accumulator 4, and performs a heating operation. At this time, the first valve device 8a is closed, the second valve device 8b is opened, and the third valve device 20 is opened.
Further, since the first connection pipe 6 is low pressure and the second connection pipe 7 is high pressure, the refrigerant inevitably flows to the fifth check valve 34 and the sixth check valve 35.
[0033]
Next, the case of heating mainly in the simultaneous cooling and heating operation will be described with reference to FIG. Here, a case where two indoor units B and C are heating and one indoor unit D is going to be cooled will be described. That is, as shown by a solid line arrow in FIG. 3, the high-temperature and high-pressure refrigerant gas discharged from the compressor 1 passes through the four-way switching valve 2, the fifth check valve 34, and the second connection pipe 7. , Flows into the relay E. The refrigerant that has flowed into the relay machine E flows into the first branch portion 10 through the gas-liquid separator 12 and the second connection pipe 7.
The refrigerant flowing into the first branching section 10 passes through the second valve device 8b connected to the indoor units B and C, and the first connection pipes 6b and 6c on the indoor unit side in this order, and the indoor unit that is going to be heated It flows into B and C, heat-exchanges with indoor air with the indoor side heat exchanger 5, is condensed and liquefied, and the room is heated. Then, the refrigerant in the liquid state is controlled by the degree of supercooling at the outlet of the indoor heat exchanger 5 and is slightly reduced in pressure through the first flow control device 9 in the substantially full open state, so that the intermediate pressure between the high pressure and the low pressure is reached. (Intermediate pressure), and the second connecting pipes 7b and 7c on the indoor unit side pass through the third valve device 20 and the second check valve 18 of the second branching section 11 and merge at the meeting section 18A.
[0034]
The refrigerant flows to the indoor unit D that is going to be cooled, with the second heat exchange unit 16 as indicated by arrows P and Q in which a part of the refrigerant joined at the meeting unit 18A of the second branching unit 11 of the relay unit E is shown. Through the first branching valve 17 connected to the indoor unit D, the third valve device 20, and the second connecting pipe 7d on the indoor unit side. After being depressurized by the first flow control device 9 controlled by the degree of superheat at the outlet of the indoor heat exchanger 5, it enters the indoor heat exchanger 5 of the indoor unit D and exchanges heat to evaporate into a gas state. The room is cooled, and flows into the first connection pipe 6 via the first valve device 8a connected to the indoor unit D of the first branching section 10.
On the other hand, the other part of the refrigerant for heating the indoor units B and C that has flowed from the indoor units B and C into the meeting portion 18A of the second branching unit 11 of the relay device E is the high pressure of the second connection pipe 7. Flows into the bypass pipe 14 through the openable / closable third flow control device 15 controlled so as to make the difference between the intermediate pressure of the second branch portion 11 constant, and the first connection as described above. In order to reach the pipe 6, the indoor unit D is merged with the cooled refrigerant and flows into the thick first connection pipe 6, and flows into the sixth check valve 35 and the heat source unit side heat exchanger 3 to exchange heat. The refrigerant that has evaporated to a gas state constitutes a circulation cycle that is sucked into the compressor 1 through the four-way switching valve 2 and the accumulator 4, and performs a heating main operation.
[0035]
At this time, the first valve device 8a connected to the indoor units B and C to be heated is closed, the second valve device 8b is opened, the third valve device 20 is opened, and the room to be cooled is The first valve device 8a connected to the machine D is opened, the second valve device 8b is closed, and the third valve device 20 is opened. Further, since the first connection pipe 6 is low pressure and the second connection pipe 7 is high pressure, the refrigerant inevitably flows to the fifth check valve 34 and the sixth check valve 35.
[0036]
Further, during this cycle, the refrigerant that has entered the bypass pipe 14 is decompressed to a low pressure by the third flow control device 15, and the refrigerant that flows into the second branch portion 11 by the second heat exchange unit 16. The refrigerant that has exchanged heat and has exchanged heat with the refrigerant flowing into the second flow rate control device 13 in the first heat exchanging unit 19 enters the first connection pipe 6, and 6, through the check valve 35, flows into the heat source unit side heat exchanger 3, exchanges heat, evaporates and enters a gas state. The refrigerant is sucked into the compressor 1 through the four-way switching valve 2 and the accumulator 4. On the other hand, as described above, the refrigerant that is cooled by the heat exchange performed by the first and second heat exchanging units 19 and 16 and has a sufficient degree of supercooling flows into the indoor unit D that is to be cooled.
[0037]
Next, the case of the cooling main in the simultaneous cooling and heating operation will be described with reference to FIG. Here, a case where two indoor units B and C are cooling and one indoor unit D is going to be heated will be described. That is, as shown by the solid arrows in FIG. 4, the high-temperature and high-pressure refrigerant gas discharged from the compressor 1 passes through the four-way switching valve 2 and exchanges an arbitrary amount of heat with the heat source unit side heat exchanger 3. It becomes a gas-liquid two-phase high-temperature and high-pressure refrigerant and flows into the relay E through the third check valve 32 and the second connection pipe 7. The refrigerant that has flowed into the relay E is sent to the gas-liquid separator 12 where the refrigerant is separated into a gas refrigerant and a liquid refrigerant, and the separated gas refrigerant passes through the second connection pipe 7 to the first of the relay E. Through the second valve device 8b of the branching section 10 and the first connecting pipe 6d on the indoor unit side, and flows into the indoor unit D to be heated, and exchanges heat with indoor air in the indoor side heat exchanger 5. To condense and heat the room.
[0038]
Furthermore, it is controlled by the degree of supercooling at the outlet of the indoor heat exchanger 5 and is slightly reduced through the first flow control device 9 in the substantially fully open state, so that it becomes an intermediate pressure between the high pressure and the low pressure (intermediate pressure). The second connection pipe 7d on the side passes through the third valve device 20, the second check valve 18 of the second branching section 11, and flows into the bypass pipe 14 from the meeting section 18A as indicated by the arrow, 3, the pressure is reduced to a low pressure by the flow rate control device 15, and heat exchange is performed with the refrigerant flowing into the second branch portion 11 by the second heat exchange unit 16, and the first heat exchange unit 19 The evaporated refrigerant that exchanges heat with the refrigerant flowing into the second flow control device 13 reaches the first connection pipe 6. On the other hand, the remaining liquid refrigerant separated by the gas-liquid separation device 12 of the relay E is cooled by exchanging heat at the first heat exchanging unit 19 and sufficiently subcooled, and then the difference between the high pressure and the intermediate pressure. As shown by the arrow, the air flows into the meeting part 17A of the second branch part 11 through the second flow rate control device 13 that is controlled so as to be constant.
[0039]
The refrigerant flows to the indoor units B and C that are going to be cooled are the first check valve 17 and the third check valve 17 connected to the indoor units B and C from the meeting part 17A of the second branching unit 11 of the relay E. Through the second connecting pipes 7b and 7c on the indoor unit side and into the indoor units B and C. And this refrigerant | coolant is pressure-reduced to low pressure by the 1st flow control apparatus 9 controlled by the superheat degree of the exit of the indoor side heat exchanger 5 of indoor unit B, C, and indoor air is made into indoor air with the indoor side heat exchanger 5. Heat exchanges evaporates and gasifies and cools the room. And the refrigerant | coolant which became the gas state flows in into the 1st connection piping 6 through the 1st connection piping 6b and 6c by the side of an indoor unit, and the 1st valve apparatus 8a of the 1st branch part 10, and bypass piping 14, after joining the heating refrigerant of the indoor unit D flowing into the first connection pipe 6 through 14, the refrigerant is sucked into the compressor 1 through the fourth check valve 33, the four-way switching valve 2, and the accumulator 4. It constitutes a circulation cycle and performs cooling main operation.
[0040]
At this time, the first valve device 8a connected to the indoor units B and C to be cooled is opened, the second valve device 8b is closed, the third valve device 20 is opened, and the room to be heated is heated. The first valve device 8a connected to the machine D is closed, the second valve device 8b is opened, and the third valve device 20 is opened. In addition, since the first connection pipe 6 is low pressure and the second connection pipe 7 is high pressure, the refrigerant inevitably flows to the third check valve 32 and the fourth check valve 33.
[0041]
Next, the control operation when the indoor unit is stopped or thermo-OFF from the operating state will be described. FIG. 5 is a flowchart showing a control operation when the indoor unit is in the cooling operation. In step S50, it is determined whether the indoor unit is in a cooling operation or not. If the cooling operation is being performed, the process proceeds to step S51. If the cooling operation is not being performed, the process returns to step S50. In step S51, it is determined whether the indoor unit is stopped or not stopped. If stopped, the process proceeds to step S53. If not stopped, the process proceeds to step S52. In step S52, it is determined whether the indoor unit is thermo-off or not thermo-off. If the thermo is turned off, the process proceeds to step S53. If the thermo is not turned off, the process returns to step S51. In step S53, the first valve device 8a and the third valve device 20 are closed, and the process returns to step S50.
[0042]
FIG. 6 is a flowchart showing the control operation when the indoor unit is in the heating operation. In step S60, it is determined whether the indoor unit is in a heating operation or not. If the heating operation is being performed, the process proceeds to step S61. If the heating operation is not being performed, the process returns to step S60. In step S61, it is determined whether the indoor unit is stopped or not stopped. If stopped, the process proceeds to step S63, and if not stopped, the process proceeds to step S62. In step S62, it is determined whether the indoor unit is thermo-off or not thermo-off. If the thermo is turned off, the process proceeds to step S63. If the thermo is not turned off, the process returns to step S61. In step S63, the second valve device 8b and the third valve device 20 are closed, and the process returns to step S60.
[0043]
As described above, when the indoor unit is stopped from the cooling operation or thermo-OFF is performed, the first and third valve devices 8a and 20 connected to the indoor unit are closed and the relay unit E and the indoor unit are disconnected. When the indoor unit is stopped from the heating operation or is turned off, the second and third valve devices 8b and 20 connected to the indoor unit are closed and the relay unit E is closed. Prevents the refrigerant in the refrigerant circuit from leaking to the indoor side even if the piping on the indoor unit side is cracked or the pipe connection part is loosened to block the refrigerant flow path to the indoor unit can do.
[0044]
Embodiment 2. FIG.
Next, a second embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 7 is a refrigerant circuit diagram showing the overall configuration of the second embodiment. In this figure, the same or corresponding parts as in FIG. The difference from FIG. 1 is that the valve device controller 21 can be driven by an external signal. That is, in FIG. 7, reference numeral 22 denotes an external signal receiving unit that receives an external signal and drives the valve device control unit 21. Further, the flow of the refrigerant during the cooling operation, the heating operation, and the simultaneous cooling / heating operation (the cooling main operation and the heating main operation) is the same as that in the above-described first embodiment, and thus the description thereof is omitted.
[0045]
Next, the control operation of the first, second, and third valve devices 8a, 8b, and 20 in the second embodiment will be described. FIG. 8 is a flowchart showing the control operation of the first, second, and third valve devices 8a, 8b, and 20. In step S80, it is determined whether the indoor unit is in a cooling operation or not. If the cooling operation is being performed, the process proceeds to step S82. If the cooling operation is not being performed, the process proceeds to step S81. In step S81, it is determined whether the indoor unit is in a heating operation or not. When the heating operation is being performed, the process proceeds to step S83, and when the heating operation is not being performed, the process returns to step S80.
In step S82, it is determined whether an external signal has been received or not.
If received, the process proceeds to step S84. If not received, the process returns to step S80. In step S84, the first and third valve devices 8a and 20 are closed, and the process returns to step S80. On the other hand, in step S83, it is determined whether an external signal has been received or not. If received, the process proceeds to step S85, and if not received, the process returns to step S80. In step S85, the second and third valve devices 8b and 20 are closed, and the process returns to step S80.
[0046]
As described above, when the external signal receiving unit 22 receives an external signal (for example, a refrigerant leak detection signal by the refrigerant sensor) while the indoor unit is in the cooling operation, the valve device control unit 21 is operated to operate the indoor unit. By closing the first and third valve devices 8a and 20 connected to the refrigerant, the refrigerant flow to the indoor side can be shut off even when a refrigerant leak is detected during the cooling operation. Refrigerant leakage can be minimized.
In addition, when the external signal receiving unit 22 receives an external signal (for example, a refrigerant leak detection signal by a refrigerant sensor) while the indoor unit is in the heating operation, the valve device control unit 21 is similarly operated to By closing the second and third valve devices 8b, 20 connected to the refrigerant, the refrigerant flow to the indoor side can be shut off even when a refrigerant leak is detected during the heating operation. Refrigerant leakage can be minimized.
[0047]
Embodiment 3 FIG.
Next, a third embodiment of the present invention will be described in detail. The overall configuration diagram of the third embodiment and the flow of the refrigerant during cooling operation, heating operation, and simultaneous cooling and heating operation (cooling main operation and heating main operation) are the same as those in FIG. To do. The difference from FIG. 1 is that when the cooling operation of the indoor unit is stopped or the thermo-off is performed, the valve device located on the upstream side with respect to the refrigerant flow direction is closed, and the valve device located on the downstream side after a predetermined time has elapsed. It is the point which made it close.
[0048]
Next, the control operation of the first, second, and third valve devices 8a, 8b, and 20 in the third embodiment will be described with reference to the flowchart of FIG.
In step S90, it is determined whether the indoor unit is in a cooling operation or not. If the cooling operation is being performed, the process proceeds to step S91. If the cooling operation is not being performed, the process returns to step S90. In step S91, it is determined whether the indoor unit is stopped or not stopped. If stopped, the process proceeds to step S93, and if not stopped, the process proceeds to step S92. In step S92, it is determined whether the indoor unit is thermo-off or not thermo-off. If the thermo is off, the process proceeds to step S93. If the thermo is not off, the process returns to step S91. In step S93, the third valve device 20 is closed, and the process proceeds to step S94. In step S94, it is determined whether or not the elapsed time T after closing the third valve device 20 has passed a preset cooling delay time T0. If it has elapsed, the process proceeds to step S95, and if it has not elapsed, the process returns to step S94. In step S95, the first flow control device 9 is closed, and the process proceeds to step S96. In step S96, the first valve device 8a is closed, and the process returns to step S90.
[0049]
When the indoor unit being cooled as described above is stopped or thermo-off, the third valve device 20 on the upstream side is first closed, and after the elapsed time T0 set in advance by the timer function has elapsed. By sequentially closing the first flow rate control device 9 and the first valve device 8a on the downstream side, the refrigerant is collected in the relay unit E or the heat source unit A without the refrigerant remaining on the indoor unit side. Can do. For this reason, it is possible to prevent the refrigerant in the refrigerant circuit from leaking to the indoor side even when the indoor unit side pipe is cracked or the pipe connection portion is loose.
[0050]
Embodiment 4 FIG.
Next, a fourth embodiment of the present invention will be described in detail. The overall configuration diagram of the fourth embodiment and the flow of the refrigerant during the cooling operation, heating operation, and simultaneous cooling / heating operation (cooling main operation and heating main operation) are the same as those in FIG. To do. The difference from FIG. 1 is that when the heating operation of the indoor unit is stopped or the thermo-OFF is performed, the valve device located on the upstream side with respect to the refrigerant flow direction is closed, and the valve device located on the downstream side after a predetermined time has elapsed. It is the point which made it close.
[0051]
Next, the control operation of the first, second, and third valve devices 8a, 8b, and 20 in the fourth embodiment will be described with reference to the flowchart of FIG.
In step S100, it is determined whether the indoor unit is in a heating operation or not. If the heating operation is being performed, the process proceeds to step S101. If the heating operation is not being performed, the process returns to step S100. In step S101, it is determined whether the indoor unit is stopped or not stopped. If stopped, the process proceeds to step S103, and if not stopped, the process proceeds to step S102. In step S102, it is determined whether the indoor unit is thermo-off or not thermo-off. If the thermo is turned off, the process proceeds to step S103. If the thermo is not turned off, the process returns to step S101.
In step S103, the second valve device 8b is closed and the process proceeds to step S104. In step S104, it is determined whether or not the elapsed time T after closing the second valve device 8b has passed a preset heating delay time T1.
If it has elapsed, the process proceeds to step S105, and if it has not elapsed, the process returns to step S104. In step S105, the first flow control device 9 is closed, and the process proceeds to step S106. In step S106, the third valve device 20 is closed, and the process returns to step S100.
[0052]
When the indoor unit that is heating as described above is stopped or thermo-OFF is performed, the second valve device 8b on the upstream side is first closed, and after an elapse time T1 preset by the timer function has elapsed. By sequentially closing the first flow rate control device 9 and the third valve device 20 on the downstream side, the refrigerant is collected in the relay device E or the heat source device A without the refrigerant remaining on the indoor unit side. Can do. For this reason, it is possible to prevent the refrigerant in the refrigerant circuit from leaking to the indoor side even when the indoor unit side pipe is cracked or the pipe connection portion is loose.
[0053]
【The invention's effect】
The air conditioner according to the present invention includes a compressor, a four-way switching valve that switches a flow path of refrigerant discharged from the compressor, and a heat source machine side heat exchanger that is connected to the four-way switching valve. A plurality of indoor units having a heat source unit, an indoor heat exchanger, and a flow control device connected thereto, and the heat source unit and each indoor unit are connected via first and second connection pipes. And a first branch portion having a valve device that connects one end of each indoor heat exchanger to the first and second connection pipes in a switchable manner, and the other end of each indoor heat exchanger And the other end of each indoor heat exchanger can be connected to the second connection pipe via a check valve connected to the valve device and a check valve connected to the valve device. Therefore, the indoor unit can be used for cooling operation or heating operation. When the operation is stopped, both the gas side and liquid side valve devices that connect the repeater to the indoor unit can be closed, so even if there is a crack in the indoor unit or a loose pipe connection, It is possible to prevent a large amount of refrigerant from leaking to the indoor unit side.
[0054]
In the air conditioner according to the present invention, since the valve device control unit is configured to perform a control operation according to an external signal, even when the indoor unit is in a cooling operation or a heating operation, for example, By receiving the refrigerant leak detection signal from the refrigerant sensor or the like as an external signal, the valve device control unit closes both the gas side and liquid side valve devices that connect the relay unit and the indoor unit. Even when there is a crack in the pipe or the pipe connection portion, a large amount of refrigerant can be prevented from leaking to the indoor unit side.
[0055]
In the air conditioner according to the present invention, when the operation of the indoor unit is stopped or the thermo-OFF is performed, the valve device control unit closes the valve device located on the upstream side with respect to the refrigerant flow direction, and a predetermined time has elapsed. Since the valve unit located downstream is closed later, when the indoor unit is stopped from the cooling operation or thermo-OFF, the portion in the refrigerant flow direction is connected at the portion connecting the relay unit and the indoor unit. As a result of first closing the liquid side valve device that is the inlet side, and sequentially closing the flow control device of the indoor unit and the gas side valve device that is the outlet side after a predetermined time set in advance by a timer function or the like, Refrigerant can be collected in the relay unit or heat source unit without staying in the indoor unit, and it is possible to prevent the refrigerant from leaking to the indoor unit side even when the piping crack on the indoor unit side or the pipe connection part is loose. Kill.
[0056]
In addition, when the indoor unit is stopped from the heating operation or the thermo is turned off, the valve device on the gas side, which is the inlet side in the refrigerant flow direction, is first closed at the portion where the relay unit and the indoor unit are connected, and the timer function As a result of sequentially closing the flow control device of the indoor unit and the liquid side valve device on the outlet side after the elapse of a predetermined time set in advance, the refrigerant can be recovered in the relay unit or heat source device without stagnation in the indoor unit. Even if there is a crack in the pipe on the indoor unit side or a looseness in the pipe connection portion, the refrigerant can be prevented from leaking to the indoor unit side.
[Brief description of the drawings]
FIG. 1 is a refrigerant circuit diagram showing an overall configuration of a first embodiment of the present invention.
FIG. 2 is an explanatory view showing an operation state of only the cooling or heating of the air-conditioning apparatus shown in FIG.
3 is an explanatory diagram showing a heating-main operation operation state in simultaneous cooling and heating operation of the air-conditioning apparatus shown in FIG. 1. FIG.
4 is an explanatory view showing a cooling-main operation operation state in the simultaneous cooling and heating operation of the air-conditioning apparatus shown in FIG. 1. FIG.
FIG. 5 is a flowchart showing a control operation of the valve device during a cooling operation according to Embodiment 1 of the present invention.
FIG. 6 is a flowchart showing a control operation of the valve device during the heating operation according to the first embodiment of the present invention.
FIG. 7 is a refrigerant circuit diagram illustrating an overall configuration of a second embodiment of the present invention.
FIG. 8 is a flowchart showing a control operation of the valve device according to the second embodiment of the present invention.
FIG. 9 is a flowchart showing a control operation of the valve device according to the third embodiment of the present invention.
FIG. 10 is a flowchart showing a control operation of the valve device in the fourth embodiment of the present invention.
FIG. 11 is a refrigerant circuit diagram showing an overall configuration of a conventional air conditioner.
12 is an explanatory diagram showing an operation state of only the cooling or heating of the air-conditioning apparatus shown in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Compressor, 2 Four way switching valve, 3 Heat source machine side heat exchanger, 4 Accumulator, 5 Indoor side heat exchanger, 6 1st connection piping, 6a, 6b, 6c 1st connection piping by the side of indoor unit, 7 2nd connection piping, 7a, 7b, 7c 2nd connection piping by the side of an indoor unit, 8a 1st valve device, 8b 2nd valve device, 9 1st flow control device, 10 1st branch part, DESCRIPTION OF SYMBOLS 11 2nd branch part, 12 Gas-liquid separator, 13 2nd flow control apparatus, 14 Bypass piping, 15 3rd flow control apparatus, 16 2nd heat exchange part, 17 1st non-return valve, 17A , 18A Meeting unit, 18 Second check valve, 19 First heat exchange unit, 20 Third valve device, 21 Valve device control unit, 22 External signal receiving unit, 32 Third check valve, 33 4 check valve, 34 fifth check valve, 35 sixth check valve, 45 first pressure detector, 46 2nd pressure detector, A heat source machine, B, C, D indoor unit, E relay machine.

Claims

One heat source machine having a compressor, a four-way switching valve for switching the flow path of the refrigerant discharged from the compressor, and a heat source machine-side heat exchanger connected to the four-way switching valve, an indoor heat exchanger And a plurality of indoor units having a flow control device connected thereto, and the heat source unit and each indoor unit are connected via first and second connection pipes, and each indoor side heat exchange is performed. Connected to the first branch portion having a valve device for switching one end of the heat exchanger to the first and second connection pipes, and the other end of each indoor heat exchanger. A second branching section configured to connect the other end of each indoor heat exchanger to the second connection pipe via a valve device and a check valve connected to the valve device. repeater and the indoor flow control device and the first branch portion of the valve device and the upper having a preparative A valve device control unit that controls opening and closing of a valve device connected to the other end of each indoor heat exchanger, and the valve device control unit detects a refrigerant leak in a refrigerant circuit that is given via an external signal receiving unit. An air conditioner controlled by a detected detection signal .

The valve device of the first branch part has two valves connected in parallel to one end of each indoor heat exchanger, and one valve is connected to the first connection pipe, The air conditioning apparatus according to claim 1, wherein the other valve is connected to the second connection pipe.

When the indoor unit stops operating or thermo-OFF, the valve device control unit closes the valve device located on the upstream side with respect to the refrigerant flow direction, and opens the valve device located on the downstream side after a predetermined time has elapsed. The air conditioner according to claim 1 or 2 , wherein the air conditioner is closed.

When the operation is stopped during the cooling operation or when the thermo is turned off, the valve device located on the upstream side is a valve device connected to the other end of each indoor heat exchanger, and the valve device located on the downstream side is 4. The air conditioner according to claim 3 , wherein the air conditioner is the flow rate control device and the valve device of the first branch section.

When the heating operation is stopped or when the thermo is turned off, the valve device located on the upstream side is the valve device of the first branch section, and the valve device located on the downstream side is the other of the indoor heat exchangers. The air conditioner according to claim 3 , wherein the air conditioner is a flow rate control device and a valve device respectively connected to the ends of the air flow.