JP3724011B2

JP3724011B2 - Air conditioner

Info

Publication number: JP3724011B2
Application number: JP19728395A
Authority: JP
Inventors: 啓夫中村; 芳廣 ▲高▼田; 素生森本; 泰久安永; 友通金子; 英範横山; 荘一小曽戸; 勉井本
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 1995-08-02
Filing date: 1995-08-02
Publication date: 2005-12-07
Anticipated expiration: 2015-08-02
Also published as: JPH0942706A

Description

【技術分野】
【０００１】
本発明は、空気調和機に関する。
【背景技術】
【０００２】
従来、空気調和機は、冷房運転や暖房運転を行うが、最近は省エネルギーに対するニーズが大きく、これを満足する一手段として室内熱交換器の伝熱面積を十分大きくすることがある。ルームエアコン等の小形の空気調和器では、室内機の寸法に制限があり、こうした制限下で伝熱面積を大きくするために、最近では、実願平２−９５１８３号（実開平４−５７０７３号）のマイクロフィルムに記載されているように室内熱交換器を室内機の前面から背面にかけて多段に曲げた構造にしたものが知られている。
【０００３】
一方、空気調和機において、湿度を下げるための除湿運転として、冷却・除湿された空気流を冷凍サイクルの凝縮熱により再加熱する方式が特開平２−１８３７７６号公報に記載されている。
【０００４】
この公報には、圧縮機、四方弁、室外熱交換器、絞り装置、室内熱交換器等を順次冷媒配管で接続し、さらに室内熱交換器を上下に二分割してこれらの間に除湿運転用の小孔付き二方弁を設けたサイクル構成が開示されている。そして除湿運転時には小孔付二方弁を閉じて冷媒を小孔を通して流すことにより絞り作用を行い、上側室内熱交換器を凝縮器、下側室内熱交換器を蒸発器とする。さらに室内空気流をこれらの室内熱交換器に並列に流し、蒸発器で冷却・除湿し、凝縮器で加熱することにより、冷え過ぎを防止しながら湿度を下げる除湿運転を可能にしている。
【発明の開示】
【発明が解決しようとする課題】
【０００５】
上記従来技術は、空気調和器の冷房・暖房という基本性能を向上させながら除湿効率を向上させる点は配慮されていない。
【０００６】
本発明の目的は、冷房・暖房運転という空気調和器の基本性能を満足しつつ、除湿運転を可能とする空気調和機を提供することにある。
【課題を解決するための手段】
【０００７】
上記目的は、圧縮機と、四方弁と、室外熱交換器と、膨張弁と、室内熱交換器とを配管により接続した冷凍サイクルを有し、室内機内に設けられた前記室内熱交換器は、除湿運転の際に加熱器となる複数系統の冷媒流路を有する第１の室内熱交換部分及び除湿運転の際に冷却器となる複数系統の冷媒流路を有する第２の室内熱交換部分とを備え、この第１の室内熱交換部分とこの第２の室内熱交換部分との間の冷媒流路に設けられ除湿運転の際に絞りとして作用する膨張機構と、前記室内熱交換器の空気流れ方向下流に配置された室内ファンとを備えた空気調和機において、前記室内熱交換器を上段部分及び下段部分を有する構造とし、この上段部分を前記第１の室内熱交換部分、この下段部分を前記第２の室内熱交換部分とし、暖房運転時に、前記第２の室内熱交換部分におけるガス冷媒が流れる入口側が空気流の風下側に配されるように前記複数系統の冷媒流路を構成し、前記第１の室内熱交換部分における暖房運転時の冷媒流出口側が前記複数系統の冷媒流路から一系統の冷媒流路となるように、かつこの一系統の冷媒流路が風上側に配されるように前記冷媒流路を構成した空気調和機。とすることで達成される。
【０００８】
以上説明したように、本発明によれば、冷房・暖房運転という空気調和機の基本性能を満足しつつ、除湿運転を可能とする空気調和機を提供することができる。
【発明を実施するための最良の形態】
【０００９】
本発明による一実施例を図１、図２及び図３に示す。
【００１０】
図１は本実施例である室内機の側断面を示す図である。図１において、室内機内に組み込まれた多段曲げ（３段）構造の室内熱交換器１は、熱的な切断線２４により、室内機における前面下段部分２と、前面側上段部分３から背面部分４にかけての部分とに熱的に分離されて構成されている。また、室内熱交換器１には、複数枚の放熱フィン２３を貫通するように設けられた伝熱管２０（○印で示した）が設けられ、伝熱管同士は接続管２１及び接続管２２（破線で示した）により接続されている。
【００１１】
さらに、除湿制御弁５は、後述するように除湿運転時に絞り作用を行う機能を有している。室内熱交換器１の前面上段部分３及び背面部分４が熱的に一体に結合され、これらと除湿制御弁５の一方の接続口が接続配管６によりに接続され、除湿制御弁５の他方の接続口は、接続配管７を介して前面上段部分３及び背面部分４とは熱的に分離された室内熱交換器１の前面下段部分２と接続されている。貫流ファンタイプの室内ファン９が回転すると、前面吸い込みグリル１０、前面側上部吸い込みグリル１１及び背面側上部吸い込みグリル１２から室内空気が流入し、フィルタ１３を介して、多段曲げ室内熱交換器１にて冷媒と熱交換されたあと室内ファン９を通り、吹出口１５から室内に吹出される。なお、１４は背面ケーシング、１５は吹出口、１６は吹出口風向板である。１７は多段曲げ室内熱交換器の前面側部分２及び３に対する露受皿、１８は多段曲げ室内熱交換器１の背面部分４に対する露受皿であり、冷房運転や除湿運転の時に生じる除湿水を受ける機能を有する。
【００１２】
図２に上記した除湿制御弁５を示した。図２(a)は除湿運転時における除湿制御弁５の動作状態を示す図であり、図２(b)は冷房及び暖房運転時の除湿制御弁５の動作状態を示す図である。弁本体３０は、弁座３１、弁体３２、弁体３２の弁部３３、接続管３４、接続管３５、弁体３２を動かす電磁モ−タ３６を備え、大きい矢印３８、３９は冷媒流方向、矢印４０は除湿運転時の冷媒流方向を示す。
【００１３】
除湿運転時には、図２(a)のように、弁体３２は電磁モ−タ３６により閉じられた状態になっている。この時、室内熱交換器１の凝縮器となる前面上段から背面にかけての部分３、４を出た高圧の凝縮液冷媒は、接続管３４から流入し、弁部３３と弁座３１との隙間で構成される狭い通路３７を矢印４０のように流れ、ここで絞り作用を受け低圧・低温の冷媒となった後、接続管３３を通って蒸発器となる室内熱交換器１の前面下段部分２に流入する。この結果、室内熱交換器１の前面上段から背面にかけての部分３、４が加熱器、前面下段部分２が冷却器となって、室内空気を加熱すると同時に冷却・除湿する温度の調整ができる除湿運転が可能になる。
【００１４】
また、冷房及び暖房運転時には、図２(b)のように、除湿制御弁５は、電磁モータ３６により弁体３２が引き上げられ全開の状態になる。この結果、接続管３４と３５はほとんど流通抵抗なしで連通し、冷媒はほとんど抵抗なしで流れることになる。
【００１５】
図３は、本実施例の全体のサイクル構成を示す図である。回転数制御等により能力可変の冷媒を圧縮する圧縮機５０、運転状態を切り換える四方弁５１、室外熱交換器５２、絞り作用の無い全開状態が可能な電動膨張弁５３、さらに前述の多段曲げ室内熱交換器１及び除湿制御弁５を加えて、これらが接続配管により環状に接続されて冷凍サイクルを構成している。また、図３においては、多段曲げ室内熱交換器１の伝熱管の流路状態の一実施例を模式的に示してあり、室内熱交換器１の前面上段部分３と背面部分４は一体に接続されて、伝熱管を接続した二系統の冷媒流路５４、５５から構成され、さらに切断線２４により熱的に分離された室内熱交換器１の前面下段部分２は５６、５７の二冷媒流路から構成されており、これらの伝熱管冷媒流路は除湿制御弁５を介して接続管６及び７により接続されている。なお、５８は室外ファンである。
【００１６】
以上の室内機構造及び冷凍サイクル構成において、除湿運転時には、四方弁５１を冷房運転時と同じ方向に切り換え、除湿制御弁５を適当に絞り電動膨張弁５３を全開とすることにより、冷媒を一点鎖線で示すように圧縮機５０、四方弁５１、室外熱交換器５２、電動膨張弁５３、室内熱交換器１の前面上段部分３及び背面部分４、除湿制御弁５、室内熱交換器１の前面下段部分２、四方弁５１、圧縮機５０の順に循環させ、室外熱交換器５２が上流側の凝縮器、室内熱交換器１の前面上段部分３及び背面部分４が下流側の凝縮器、室内熱交換器１の前面下段部分２が蒸発器となるように運転する。そして、室内空気を室内ファン９により矢印５９で示すように流すと、室内空気は蒸発器として作用する前面下段熱交換器部分２で冷却・除湿されると同時に、下流側の凝縮器すなわち加熱器となる室内熱交換器の前面上段部分３及び背面部分４で加熱され、さらにこれらの空気が混合されて室内に吹き出される。この場合、回転数を制御して圧縮機５０の能力や室内ファン９及び室外ファン５８の送風能力を制御することにより、室内熱交換器１の前面下段部分２、前面上段部分３及び背面部分４の能力を調節することができ、最終的には除湿量や吹き出し空気温度を広い範囲で変えることができる。また、室内熱交換器１を多段曲げ熱交換器にして伝熱面積を大きくしたことにより、相対的に冷却器部分も大きくなり除湿能力を向上できる。さらに、除湿運転において加熱器での加熱量を大きくするためには、室内熱交換器の加熱器部分の割合を冷却器部分に比べて大きくする必要があるが、室内熱交換器１を多段曲げ熱交換器にしてこの前面側上段から背面にかけての部分を加熱器、前面側下段部分を冷却器になるようにすることにより、加熱器部分の伝熱面積を冷却器部分より大きくすることができる。
【００１７】
次に、冷房運転時には、除湿制御弁５を開き電動膨張弁５３を適当に絞ることにより、冷媒を実線の矢印で示すように循環させ、室外熱交換器５２を凝縮器、多段曲げ室内熱交換器１を蒸発器として室内の冷房を行う。暖房運転時には、四方弁５１を切り替え除湿制御弁５を開き電動膨張弁５２を適当に絞ることにより、冷媒を破線の矢印で示すように循環させ、多段曲げ室内熱交換器１を凝縮器、室外熱交換器５２を蒸発器として室内の暖房を行う。
【００１８】
そして冷房、暖房の各運転に対してもサイクル性能及び多段曲げ室内熱交換器１での熱交換性能を確保して効率良く運転する必要がある。以下、この方法について説明する。
【００１９】
まず、図３において、多段曲げ室内熱交換器１を室内機の前面上段から背面にかけての部分３、４と前面下段部分２の二つに熱的に分割し、これらを除湿制御弁５を介して直列に接続してあるため、冷房運転及び暖房運転のうち特に冷房運転においては、室内熱交換器１は全体が低圧でガス冷媒の比容積が大きくて体積流量が多くなる蒸発器となるため、ここでの圧力損失が大きくなってサイクルの性能が低下する。この問題を解決するために、図３においては、多段曲げ室内熱交換器１の前面上段から背面にかけての部分３、４と前面下段部分２の各冷媒流路をそれぞれ５４、５５と５６、５７の二系統にしてある。この結果、冷媒流路での圧力損失が十分小さくなり、特に冷房運転での性能低下を防ぐことができる。
【００２０】
また暖房運転での性能をさらに向上するためには、室内熱交換器の出口で十分なサブクールを取る必要がある。このサブクール域では、冷媒が液状態であると同時に冷媒温度が凝縮温度から徐々に下がることから、液冷媒流の速度を速めて伝熱管内の熱伝達率を高めてやると同時に、伝熱管が風上側になるようにして熱交換前の比較的温度の低い空気流と熱交換するようにする必要がある。室内熱交換器１の前面下段部分２における暖房運転時の入口部分では高温ガス冷媒の温度が凝縮温度まで低下するため、この部分でも冷媒流と空気流とが対向流になるようにしてやる必要がある。このための他の実施例による室内熱交換器１での冷媒流路構成を図４に示す。図３と同一番号を付けたものは同一部分を示す。図４においては、多段曲げ室内熱交換器１の前面上段から背面にかけての部分３、４を、風上側に設けた一系統の冷媒流路部分６０と二系統の冷媒流路部分６１、６２から構成する。さらに室内熱交換器１の前面下段部分２の冷媒流路を５６、５７の二系統にすると同時に前面下段部分２における暖房運転時の冷媒流入口部分を空気流の風下側に設けた配管構成にしてある。
【００２１】
このサイクル構成により、暖房運転においては、圧縮機５０を出て四方弁５１を通った後の高温高圧のガス冷媒が室内熱交換器１に入り、前面下段部分２の冷媒流路が二系統の伝熱管５６、５７を分流して通った後、除湿制御弁５を通って室内熱交換器１の前面上段から背面にかけての部分３、４に入り、冷媒流路が二系統の伝熱管６１、６２を分流して流れる。この流れは、この後合流して冷媒流路が一系統の伝熱管６０を流れる。この場合、室内熱交換器１の前面下段部分２では高温のガス冷媒が流れる入口側が空気流の風下側になり二相冷媒の流れる出口側が温度の低い空気流の風上側になるため、前面下段部分２では冷媒流と空気流とが熱交換性能の優れた対向流状態となる。また前面上段から背面にかけての部分３、４では冷媒流の出口側が一系統冷媒流路の伝熱管６０となっており、飽和温度から徐々に温度の下がるサブクール域に設けられた伝熱管６０は温度の低い上流側空気流と熱交換をするため、十分なサブクールが取れ、暖房性能を向上することができる。
【００２２】
また、冷房運転においては、電動膨張弁５３で絞られ低圧・低温になった冷媒が室内熱交換器１に入り、前面上段から背面にかけての熱交換器部分３、４において一系統の伝熱管６０を通ったあと分流して二系統の伝熱管６１、６２に入り、さらに除湿制御弁５を通って前面下段部分２に入り二系統の伝熱管５６、５７に分流して流れる。しかし、伝熱管６０では冷媒の乾き度が比較的小さいため一系統の冷媒流路でも圧力損失は比較的小さい。また乾き度が比較的大きい伝熱管６１、６２と５６、５７の部分では冷媒流路をそれぞれ二系統にしたことから圧力損失が十分小さくなる。この結果、圧力損失による冷房性能の低下を防ぐことができる。
【００２３】
なお、図３及び図４に示す実施例では、室内熱交換器１の伝熱管を二系統に分ける場合及び一系統と二系統を組み合わせた場合を示したが、これらに限るものではなく、冷媒流路をさらに多くの系統に分ける事も可能であり、この場合も室内熱交換器１での冷媒流圧力損失を低減し、特に冷房性能の低下を防止できる。但し、冷媒流路をあまり多系統にすると、冷媒流の圧力損失は低下するが、熱伝達率の低下が著しく、冷房運転及び暖房運転における能力や動作係数といった空気調和機全体の性能が低下してしまうため、最適な系統数の冷媒流路に設定する必要があり、この系統数は主に冷媒配管の内径に応じて決定される。
【００２４】
ところで図１〜図４の実施例では室内熱交換器１を、前面下段部分２、前面上段部分３、背面部分４の三段に曲げた場合を示したが、これに限るものではなく、各部分を必要に応じてそれぞれ多段に構成しても良い。図５には熱的な切断線６３の下段部分である室内熱交換器１の前面下段部分２'を６４、６５、６６の３段にした場合を示す。これにより伝熱面積を図３より大きくできる。さらには図６に示すように前面下段から前面上段、背面までを折れ線でなく連続した曲線にした一体構造にして、さらに除湿運転時に加熱器となる前面上段から背面にかけての部分と冷却器となる前面下段部分とを、切断線６７により６８と６９の二つに熱的に分離した構造にしても良く、同様に伝熱面積を大きくすることができる。特に小形の空気調和機であるルームエアコン等では、室内熱交換器を収納するスペースが十分に取れないことが多く、この場合には室内熱交換器の曲げ回数を多くしたり、曲線状にすることにより、狭いスペースに十分な伝熱面積を持つ室内熱交換器を収納でき、冷房、暖房さらには除湿運転での性能を向上することができる。
【００２５】
また図１に示す実施例では、除湿運転時において加熱器となる伝熱管の本数を冷却・除湿器となる伝熱管の本数より多くしてあるが、これは加熱器での加熱能力を多くして暖房気味の除湿運転を行う上で有効となるからである。すなわち、除湿運転において、冷却器の能力に比べて、加熱器の能力を十分高くできることから、暖房気味の除湿運転がやり易くなる。
【００２６】
ここで除湿運転において、図３における室外ファン５８の送風能力を落とすと室外熱交換器５２で外気に放熱する能力が減少して室内熱交換器１の加熱器部分３、４での放熱能力が増大する。また圧縮機５０の能力を増す事により加熱器部分３、４での加熱能力を増したり、冷却器部分２での除湿能力を増すことができる。また、室内ファン９の送風能力を変えることによりいろいろな使用状態に適した除湿運転を行うことができる。たとえば通常の除湿運転では人の好みに応じて室内風量を変え、洗濯物を乾燥するときには室内風量を増して運転し、寝るときには室内風量を落として運転するようにする。この場合、最近ではＤＣモータファンやインバータ圧縮機が採用されており、これらは回転数の制御が容易なことからファンや圧縮機の能力を容易に変えて、除湿運転における加熱能力を広い範囲で変えて吹出温度を冷房気味から等温気味、暖房気味まで変えたり、除湿能力を変えたり、さらには使用状態に合わせて室内風量を変えて上記種々の除湿運転を行うことができる。
【００２７】
室内機の全面から背面にかけて設けた室内熱交換器構造に対して、図１乃至図６では、前面上段から背面にかけての部分３、４と前面下段部分２とを熱的に２分割して、これらの間に除湿制御弁５を設けた構成としている。この構成を、前面上段部分３と背面部分４との間に切断線を入れて熱的に２分割し、この間に除湿制御弁５を設けた構成としてもよい。すなわち、除湿運転時においては、前面上段部分３及び前面下段部分２が加熱器として作用し、背面部分４が冷却器として作用することとなる。この場合においても、加熱部分が冷却部分よりも大きいので、暖房気味除湿運転時に問題となる再熱量の不足を防止することができる。さらに、冷却器の下側に加熱器が配置されないことから冷却器で生じた除湿水が加熱器にかかって再蒸発することがない。また、室内熱交換器の前面部分２、３及び背面部分を夫々２系統以上の冷媒流路としたり、前面部分で冷房運転時の冷媒流入り口部分を１系統にして空気流の風上側に配置したり、さらには背面部分で暖房運転時の冷媒流入り口部分を空気流の風上側に配置することにより、冷房運転や暖房運転において圧力損失を低減すると共に空気流と冷媒流を対向流とすることができる。さらに、暖房運転において、十分なサブクールを取ることができる。このため、冷房運転及び暖房運転において、図３乃至図４に記載の実施例と同様に十分効率のよい運転を行うことができる。
【００２８】
また図３における除湿制御弁５や電動膨張弁５３はキャピラリーチューブあるいは通常の膨張弁と二方弁とを並列に設けた構成のものにしてもよく（図示省略）、二方弁の開閉により、図３の実施例と同様の作用を実現することができる。
【００２９】
さらにまた以上説明した実施例においては、空気調和機でよく使用されるＨＣＦＣ２２（ハイドロクロロフルオロカーボン２２の略）等の単一冷媒を使用する場合に付いて説明してきた。しかし最近は、オゾン層破壊や地球温暖化の点からＨＣＦＣ２２に代わる代替冷媒の研究が盛んになっており、代替冷媒としては単一冷媒だけでなく、混合冷媒の使用が検討されている。これに対して、図１及び図２に示す実施例で述べてきた室内機の構造、サイクル構成、運転の制御方法を適用できることは明らかであり、同様の効果が得られる。
【００３０】
以上本実施例によれば、コンパクトな室内機の中に十分大きな熱交換器を設けるために、室内熱交換器を多段曲げあるいは曲線状にすると同時に室内機の前面から背面にかけて設けた構造にし、さらに該室内熱交換器を室内機の前面下段部分と前面上段から背面にかけての部分あるいは前面部分と背面部分を熱的に二分割しその間に除湿運転時に絞り作用を行う除湿制御弁を設けて、除湿運転時には室内熱交換器の前面下段部分あるいは背面部分が冷却器、前面上段から背面にかけての部分あるいは前面部分が加熱器となる冷凍サイクル構成にした。この結果、コンパクトな室内機においても、冷房及び暖房運転での性能を十分向上して省電力を図り、除湿運転では除湿効率（除湿量／消費電力）を向上させると共に冷却器で生じた除湿水が加熱器にかかって再蒸発することの無いようにした。
【００３１】
また、熱的に二分割した室内熱交換器の各々の冷媒流路をそれぞれ二系統以上にして室内機における前面から背面にかけて設けた室内熱交換器での冷媒流の流通抵抗の増加を防止したり、室内熱交換器の冷媒流路における暖房運転時の出口部分を一系統にして暖房運転時に十分な冷媒サブクールが取れるようにしたり、さらには室内熱交換器における冷媒流と空気流とができるだけ対向流になるような配管構成にしたことにより、熱交換器を大きくして冷媒流路が長くなったり、除湿制御弁を設けたことによる性能の低下を防ぐことができる。
【００３２】
また、室外ファン及び圧縮機を能力制御可能なものにしてこれらの機器の能力を適当に制御することにより加熱器での加熱量を広い範囲で制御して、除湿水量を十分取れる状態で、暖房気味、等温気味、冷房気味の除湿運転を行うと同時に、室内ファンの能力制御により種々の利用形態の除湿運転を行うことができる。
【００３３】
さらにまた、以上のような除湿運転方法及び室内熱交換器の配管構成は、単一冷媒、混合冷媒を問わず適用でき、同様の効果を得ることができる。
【図面の簡単な説明】
【００３４】
【図１】本発明の一実施例である空気調和機の室内機構造を示す図である。
【図２】図１における除湿制御弁の構造及動作状態を示す図である。
【図３】本発明の一実施例である空気調和機のサイクル構成を示す図である。
【図４】本発明の他の実施例である室内熱交換器の配管構成を示す図である。
【図５】本発明の他の実施例である室内熱交換器の形状を示す図である。
【図６】本発明のさらに他の実施例である室内熱交換器の形状を示す図である。
【符号の説明】
【００３５】
１…室内熱交換器、２、２'…室内熱交換器の前面下段部分、３…室内熱交換器の前面上段部分、４…室内熱交換器の背面部分、５…除湿制御弁、６、７…室内熱交換器と除湿制御弁との接続配管、９…室内ファン、１０…前面吸い込みグリル、１１…上面吸い込みグリル、１２…背面吸い込みグリル、１３…フィルタ、１４…背面ケーシング、１５…吹き出し口、１６…吹出口風向板、１７…前面露受皿、１８…背面露受け皿、２０…伝熱管、２１、２２…伝熱管の接続配管、２３…放熱フィン、２４、６３、６７…熱的切断線、
３０…弁本体、３１…弁座、３２…弁体、３３…弁部、３４、３５…接続管、３６…電磁モータ、３７…除湿運転時の冷媒流路、５０…圧縮機、５１…四方弁、５２…室外熱交換器、５３…電動膨張弁、５４、５５、５６、５７、６０、６１、６２…冷媒流路、５８…室外ファン、５９…室内空気流方向、６４、６５、６６、６８、６９…熱交換器部分。【Technical field】
[0001]
The present invention relates to an air conditioner.
[Background]
[0002]
Conventionally, an air conditioner performs a cooling operation or a heating operation. Recently, there is a great need for energy saving, and as a means for satisfying this, the heat transfer area of the indoor heat exchanger may be sufficiently increased. In small air conditioners such as room air conditioners, there are restrictions on the dimensions of indoor units, and recently, in order to increase the heat transfer area under such restrictions, No. 2-95183 (No. 4-57073). ), A structure in which an indoor heat exchanger is bent in multiple stages from the front to the back of the indoor unit is known.
[0003]
On the other hand, in an air conditioner, as a dehumidifying operation for lowering humidity, a system in which a cooled and dehumidified air flow is reheated by heat of condensation of a refrigeration cycle is described in Japanese Patent Laid-Open No. 2-183776.
[0004]
In this publication, a compressor, a four-way valve, an outdoor heat exchanger, an expansion device, an indoor heat exchanger, etc. are sequentially connected by refrigerant piping, and the indoor heat exchanger is divided into two parts in the vertical direction to perform dehumidification operation between them. A cycle configuration in which a two-way valve with a small hole is provided is disclosed. During the dehumidifying operation, the two-way valve with a small hole is closed and the refrigerant is allowed to flow through the small hole to perform a throttling action, and the upper indoor heat exchanger is a condenser and the lower indoor heat exchanger is an evaporator. Furthermore, the indoor air flow is allowed to flow in parallel to these indoor heat exchangers, cooled and dehumidified with an evaporator, and heated with a condenser, thereby enabling a dehumidifying operation to reduce humidity while preventing overcooling.
DISCLOSURE OF THE INVENTION
[Problems to be solved by the invention]
[0005]
The prior art described above, the viewpoint of improving the dehumidifying efficiency while improving the basic performance of cooling and heating of the air conditioner has not been consideration.
[0006]
An object of the present invention is to provide an air conditioner that enables a dehumidifying operation while satisfying the basic performance of the air conditioner such as cooling and heating operations.
[Means for Solving the Problems]
[0007]
The above object has a refrigeration cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger are connected by piping, and the indoor heat exchanger provided in the indoor unit is The first indoor heat exchange part having a plurality of refrigerant flow paths serving as heaters during the dehumidifying operation and the second indoor heat exchange part having a plurality of refrigerant flow paths serving as coolers during the dehumidifying operation with the door, and the expansion mechanism which acts as a stop during the dehumidifying operation is provided in the refrigerant channel between the first indoor heat exchanger portion and the second indoor heat exchanger portion, said indoor heat exchanger In an air conditioner including an indoor fan arranged downstream in the air flow direction, the indoor heat exchanger has a structure having an upper part and a lower part, and the upper part is the first indoor heat exchange part, the lower part. During the heating operation, the portion is the second indoor heat exchange portion The plurality of systems of refrigerant flow paths are configured such that the inlet side through which the gas refrigerant flows in the second indoor heat exchange portion is disposed on the leeward side of the air flow, and during the heating operation in the first indoor heat exchange portion Air conditioning in which the refrigerant flow path is configured so that the refrigerant outlet side of the plurality of refrigerant flows from the plurality of refrigerant flow paths into a single refrigerant flow path, and the one refrigerant flow path is arranged on the windward side. Machine. Is achieved.
[0008]
As described above, according to the present invention, it is possible to provide an air conditioner that enables a dehumidifying operation while satisfying the basic performance of the air conditioner such as cooling and heating operations.
BEST MODE FOR CARRYING OUT THE INVENTION
[0009]
One embodiment according to the present invention is shown in FIGS.
[0010]
FIG. 1 is a view showing a side cross section of an indoor unit according to the present embodiment. In FIG. 1, an indoor heat exchanger 1 having a multi-stage bending (three-stage) structure incorporated in an indoor unit includes a front lower part 2 and a rear part from the front upper part 3 in the indoor unit by a thermal cutting line 24. It is configured to be thermally separated into a portion over 4. Further, the indoor heat exchanger 1 is provided with a heat transfer tube 20 (shown by a circle) provided so as to penetrate through the plurality of radiation fins 23, and the heat transfer tubes are connected to each other by a connection tube 21 and a connection tube 22 ( Connected by a broken line).
[0011]
Further, the dehumidification control valve 5 has a function of performing a throttling action during a dehumidifying operation as will be described later. The front upper portion 3 and the rear portion 4 of the indoor heat exchanger 1 are thermally coupled together, and one of the connection ports of the dehumidification control valve 5 is connected to the connection pipe 6, and the other of the dehumidification control valve 5 is connected. The connection port is connected to the lower front portion 2 of the indoor heat exchanger 1 that is thermally separated from the upper front portion 3 and the rear portion 4 through the connection pipe 7. When the cross-flow fan type indoor fan 9 rotates, room air flows from the front suction grill 10, the front side upper suction grill 11, and the rear side upper suction grill 12, and passes through the filter 13 to the multistage bending indoor heat exchanger 1. After the heat exchange with the refrigerant, the air passes through the indoor fan 9 and is blown into the room from the blowout port 15. In addition, 14 is a back casing, 15 is a blower outlet, 16 is a blower outlet wind direction board. 17 is a dew tray for the front side portions 2 and 3 of the multi-stage bending indoor heat exchanger, and 18 is a dew tray for the rear portion 4 of the multi-stage bending indoor heat exchanger 1, and receives dehumidified water generated during cooling operation and dehumidifying operation. It has a function.
[0012]
FIG. 2 shows the dehumidification control valve 5 described above. FIG. 2 (a) is a diagram showing the operating state of the dehumidification control valve 5 during the dehumidifying operation, and FIG. 2 (b) is a diagram showing the operating state of the dehumidifying control valve 5 during the cooling and heating operations. The valve body 30 includes a valve seat 31, a valve body 32, a valve portion 33 of the valve body 32, a connection pipe 34, a connection pipe 35, and an electromagnetic motor 36 that moves the valve body 32, and large arrows 38 and 39 indicate refrigerant flow. The direction and the arrow 40 indicate the refrigerant flow direction during the dehumidifying operation.
[0013]
During the dehumidifying operation, the valve element 32 is closed by the electromagnetic motor 36 as shown in FIG. At this time, the high-pressure condensate refrigerant that has exited the portions 3 and 4 from the upper front to the rear, which is the condenser of the indoor heat exchanger 1, flows in from the connection pipe 34, and the gap between the valve portion 33 and the valve seat 31. After flowing through a narrow passage 37 as shown by an arrow 40 and being subjected to a throttling action to become a low-pressure / low-temperature refrigerant, the lower portion of the front surface of the indoor heat exchanger 1 serving as an evaporator through the connecting pipe 33 Flows into 2. As a result, the portions 3 and 4 from the upper front to the rear of the indoor heat exchanger 1 serve as a heater and the lower front portion 2 serves as a cooler so that the indoor air is heated and at the same time the temperature for cooling and dehumidifying can be adjusted. Driving becomes possible.
[0014]
Further, during the cooling and heating operation, as shown in FIG. 2B, the dehumidification control valve 5 is fully opened by the valve body 32 being pulled up by the electromagnetic motor 36. As a result, the connecting pipes 34 and 35 communicate with each other with almost no flow resistance, and the refrigerant flows with almost no resistance.
[0015]
FIG. 3 is a diagram showing an overall cycle configuration of the present embodiment. Compressor 50 that compresses a variable capacity refrigerant by rotational speed control, etc., four-way valve 51 that switches the operation state, outdoor heat exchanger 52, electric expansion valve 53 that can be fully opened without a throttling action, and the aforementioned multistage bending chamber A heat exchanger 1 and a dehumidification control valve 5 are added, and these are connected in an annular shape by a connection pipe to constitute a refrigeration cycle. Moreover, in FIG. 3, one Example of the flow-path state of the heat exchanger tube of the multistage bending indoor heat exchanger 1 is shown typically, The front upper stage part 3 and the back surface part 4 of the indoor heat exchanger 1 are united. The front lower stage portion 2 of the indoor heat exchanger 1 that is connected and is composed of two refrigerant flow paths 54 and 55 connected with heat transfer tubes and further thermally separated by the cutting line 24 is 56 and 57 two refrigerants. These heat transfer pipe refrigerant flow paths are connected by connecting pipes 6 and 7 through a dehumidification control valve 5. Reference numeral 58 denotes an outdoor fan.
[0016]
In the indoor unit structure and the refrigeration cycle configuration described above, at the time of dehumidifying operation, the four-way valve 51 is switched in the same direction as at the time of cooling operation, and the dehumidifying control valve 5 is appropriately throttled to fully open the electric expansion valve 53 so that one point of refrigerant is obtained. As indicated by a chain line, the compressor 50, the four-way valve 51, the outdoor heat exchanger 52, the electric expansion valve 53, the front upper stage portion 3 and the rear portion 4 of the indoor heat exchanger 1, the dehumidification control valve 5, and the indoor heat exchanger 1 The front lower part 2, the four-way valve 51, and the compressor 50 are circulated in this order, the outdoor heat exchanger 52 is the upstream condenser, the front upper part 3 and the rear part 4 of the indoor heat exchanger 1 are the downstream condensers, It operates so that the front lower stage part 2 of the indoor heat exchanger 1 may become an evaporator. When the indoor air is flown by the indoor fan 9 as indicated by the arrow 59, the indoor air is cooled and dehumidified in the front lower heat exchanger portion 2 acting as an evaporator, and at the same time, a downstream condenser or heater It is heated by the front upper stage part 3 and the rear part 4 of the indoor heat exchanger, and these air are mixed and blown out into the room. In this case, by controlling the rotational speed to control the capacity of the compressor 50 and the blowing capacity of the indoor fan 9 and the outdoor fan 58, the front lower part 2, the front upper part 3 and the rear part 4 of the indoor heat exchanger 1 are controlled. Can be adjusted, and finally, the amount of dehumidification and the temperature of the blown air can be changed over a wide range. Moreover, by making the indoor heat exchanger 1 into a multistage bending heat exchanger and increasing the heat transfer area, the cooler portion becomes relatively large and the dehumidifying ability can be improved. Furthermore, in order to increase the heating amount in the heater in the dehumidifying operation, it is necessary to increase the proportion of the heater portion of the indoor heat exchanger as compared to the cooler portion, but the indoor heat exchanger 1 is bent in multiple stages. By making the part from the front side upper stage to the back side a heater and making the front side lower stage part a cooler as a heat exchanger, the heat transfer area of the heater part can be made larger than the cooler part. .
[0017]
Next, during the cooling operation, the dehumidification control valve 5 is opened and the electric expansion valve 53 is appropriately throttled so that the refrigerant is circulated as indicated by the solid line arrow, and the outdoor heat exchanger 52 is exchanged with a condenser and multistage bending indoor heat exchange. The room 1 is cooled using the apparatus 1 as an evaporator. During the heating operation, the four-way valve 51 is switched, the dehumidification control valve 5 is opened, and the electric expansion valve 52 is appropriately throttled to circulate the refrigerant as indicated by the dashed arrows, and the multistage bending indoor heat exchanger 1 is connected to the condenser and the outdoor The room is heated using the heat exchanger 52 as an evaporator.
[0018]
And it is necessary to ensure efficient cycle operation and heat exchange performance in the multistage bending indoor heat exchanger 1 for each operation of cooling and heating. Hereinafter, this method will be described.
[0019]
First, in FIG. 3, the multi-stage bending indoor heat exchanger 1 is thermally divided into two parts 3 and 4 and a front lower part 2 from the upper front to the rear of the indoor unit, and these are passed through a dehumidification control valve 5. In the cooling operation and the heating operation, particularly in the cooling operation, the indoor heat exchanger 1 is an evaporator whose overall pressure is low, the specific volume of the gas refrigerant is large, and the volume flow rate is increased. In this case, the pressure loss is increased and the cycle performance is lowered. In order to solve this problem, in FIG. 3, the refrigerant flow paths 54, 55, 56, 57 of the portions 3, 4 and the front lower portion 2 from the upper front to the rear of the multi-stage bending indoor heat exchanger 1 are respectively shown. There are two systems. As a result, the pressure loss in the refrigerant flow path becomes sufficiently small, and it is possible to prevent the performance deterioration particularly in the cooling operation.
[0020]
In order to further improve the performance in the heating operation, it is necessary to take a sufficient subcool at the outlet of the indoor heat exchanger. In this subcool region, the refrigerant temperature is gradually lowered from the condensing temperature at the same time as the refrigerant is in the liquid state. Therefore, the liquid refrigerant flow speed is increased to increase the heat transfer coefficient in the heat transfer tube, and at the same time, the heat transfer tube is It is necessary to exchange heat with an air stream having a relatively low temperature before heat exchange so that it is on the windward side. Since the temperature of the high-temperature gas refrigerant is reduced to the condensation temperature at the entrance portion during heating operation in the lower front portion 2 of the indoor heat exchanger 1, it is necessary to make the refrigerant flow and the air flow counter flow in this portion as well. is there. FIG. 4 shows a refrigerant flow path configuration in the indoor heat exchanger 1 according to another embodiment for this purpose. The same reference numerals as those in FIG. 3 denote the same parts. In FIG. 4, the parts 3 and 4 from the front upper stage to the rear face of the multi-stage bending indoor heat exchanger 1 are separated from one system of refrigerant flow path parts 60 and two systems of refrigerant flow path parts 61 and 62 provided on the windward side. Constitute. Further, the refrigerant flow path of the lower front portion 2 of the indoor heat exchanger 1 is made into two systems 56 and 57, and at the same time, the refrigerant inlet portion in the lower front portion 2 during heating operation is provided on the leeward side of the air flow. It is.
[0021]
With this cycle configuration, in the heating operation, the high-temperature and high-pressure gas refrigerant after leaving the compressor 50 and passing through the four-way valve 51 enters the indoor heat exchanger 1, and the refrigerant flow path in the front lower stage portion 2 has two systems. After diverting and passing through the heat transfer tubes 56 and 57, the dehumidification control valve 5 is passed through the portions 3 and 4 from the upper front to the rear of the indoor heat exchanger 1, and the refrigerant flow path has two heat transfer tubes 61, 62 is divided and flows. This flow then merges and the refrigerant flow passes through the heat transfer tube 60 of one system. In this case, in the lower front portion 2 of the indoor heat exchanger 1, the inlet side through which the high-temperature gas refrigerant flows is the leeward side of the air flow, and the outlet side through which the two-phase refrigerant flows is the leeward side of the low-temperature air flow. In part 2, the refrigerant flow and the air flow are in a counterflow state with excellent heat exchange performance. Further, in the portions 3 and 4 from the upper front stage to the rear face, the outlet side of the refrigerant flow is a heat transfer pipe 60 of a single refrigerant flow path, and the heat transfer pipe 60 provided in the subcool region where the temperature gradually decreases from the saturation temperature Since the heat exchange with the low upstream air flow is sufficient, a sufficient subcooling can be obtained and the heating performance can be improved.
[0022]
In the cooling operation, the low-pressure and low-temperature refrigerant that is throttled by the electric expansion valve 53 enters the indoor heat exchanger 1, and a single heat transfer tube 60 is formed in the heat exchanger portions 3 and 4 from the upper front to the rear. After passing through, the flow is divided to enter the two heat transfer tubes 61 and 62, further passes through the dehumidification control valve 5, enters the front lower stage portion 2, and flows to the two heat transfer tubes 56 and 57. However, in the heat transfer tube 60, since the dryness of the refrigerant is relatively small, the pressure loss is relatively small even in one system of the refrigerant flow path. In addition, the heat loss tubes 61, 62, 56, and 57 having a relatively high degree of dryness have a sufficiently small pressure loss because the refrigerant flow paths are two systems. As a result, a decrease in cooling performance due to pressure loss can be prevented.
[0023]
In addition, in the Example shown in FIG.3 and FIG.4, although the case where the heat exchanger tube of the indoor heat exchanger 1 was divided into two systems and the case where one system and two systems were combined was shown, it does not restrict to these, It is also possible to divide the flow path into more systems. In this case as well, the refrigerant flow pressure loss in the indoor heat exchanger 1 can be reduced, and in particular, the cooling performance can be prevented from being lowered. However, if there are too many refrigerant flow paths, the pressure loss of the refrigerant flow will decrease, but the heat transfer rate will decrease significantly, and the overall performance of the air conditioner, such as the capacity and operating coefficient in cooling and heating operations, will decrease. Therefore, it is necessary to set the optimum number of refrigerant flow paths, and this number is mainly determined according to the inner diameter of the refrigerant pipe.
[0024]
In the embodiment of FIGS. 1 to 4, the indoor heat exchanger 1 is shown in a case where it is bent into three stages of a front lower part 2, a front upper part 3, and a rear part 4, but the present invention is not limited to this. The portions may be configured in multiple stages as required. FIG. 5 shows a case where the front lower portion 2 ′ of the indoor heat exchanger 1, which is the lower portion of the thermal cutting line 63, has three stages 64, 65, and 66. Thereby, a heat transfer area can be made larger than FIG. Furthermore, as shown in FIG. 6, an integrated structure in which the front lower stage, the front upper stage, and the rear face are not curved lines but a continuous curve, and a part from the front upper stage to the rear that becomes a heater during dehumidification operation and a cooler are formed. The front lower stage portion may be thermally separated into two parts 68 and 69 by a cutting line 67, and the heat transfer area can be increased in the same manner. In particular, room air conditioners, which are small air conditioners, often do not have enough space to store the indoor heat exchanger. In this case, the indoor heat exchanger can be bent more times or curved. Thus, an indoor heat exchanger having a sufficient heat transfer area in a narrow space can be accommodated, and the performance in cooling, heating, and dehumidifying operation can be improved.
[0025]
In the embodiment shown in FIG. 1, the number of heat transfer tubes serving as heaters during the dehumidifying operation is greater than the number of heat transfer tubes serving as cooling / dehumidifiers, but this increases the heating capacity of the heater. This is because it is effective in performing dehumidifying operation with a heating effect. That is, in the dehumidifying operation, the capacity of the heater can be made sufficiently higher than the capacity of the cooler, so that it is easy to perform a dehumidifying operation with a heating effect.
[0026]
Here, in the dehumidifying operation, if the blowing capacity of the outdoor fan 58 in FIG. Increase. Further, by increasing the capacity of the compressor 50, it is possible to increase the heating capacity in the heater parts 3 and 4 and increase the dehumidifying capacity in the cooler part 2. Moreover, the dehumidification operation suitable for various use conditions can be performed by changing the ventilation capability of the indoor fan 9. For example, in a normal dehumidifying operation, the indoor air volume is changed according to the preference of the person, the indoor air volume is increased when the laundry is dried, and the indoor air volume is decreased when sleeping. In this case, recently, DC motor fans and inverter compressors have been adopted, and these are easy to control the rotation speed, so the ability of the fan and compressor can be easily changed to increase the heating capacity in the dehumidifying operation over a wide range. The above-mentioned various dehumidifying operations can be performed by changing the blowing temperature from a cooling to an isothermal or heating feeling, changing the dehumidifying ability, or changing the indoor air volume according to the use state.
[0027]
For the indoor heat exchanger structure provided from the entire surface to the back of the indoor unit, in FIGS. 1 to 6, the parts 3 and 4 and the front lower part 2 from the upper front stage to the rear part are thermally divided into two parts. The dehumidification control valve 5 is provided between them. This configuration may be a configuration in which a cutting line is inserted between the front upper stage portion 3 and the back portion 4 to thermally divide into two, and a dehumidification control valve 5 is provided therebetween. That is, during the dehumidifying operation, the front upper stage part 3 and the front lower stage part 2 act as a heater, and the back part 4 acts as a cooler. Even in this case, since the heating part is larger than the cooling part, it is possible to prevent the shortage of the reheat amount that becomes a problem during the heating-like dehumidifying operation. Furthermore, since the heater is not disposed below the cooler, dehumidified water generated in the cooler is not re-evaporated on the heater. In addition, the front part 2, 3 and the back part of the indoor heat exchanger have two or more refrigerant flow paths, respectively, and the refrigerant inlet port at the time of cooling operation in the front part is arranged on the windward side of the air flow. In addition, the refrigerant inlet at the time of heating operation is arranged on the windward side of the air flow at the back portion, so that pressure loss is reduced in the cooling operation and heating operation, and the air flow and the refrigerant flow are made to face each other. be able to. Furthermore, a sufficient subcool can be taken in the heating operation. For this reason, in the cooling operation and the heating operation, a sufficiently efficient operation can be performed as in the embodiments described in FIGS. 3 to 4.
[0028]
Further, the dehumidification control valve 5 and the electric expansion valve 53 in FIG. 3 may have a configuration in which a capillary tube or a normal expansion valve and a two-way valve are provided in parallel (not shown). The same operation as the embodiment of FIG. 3 can be realized.
[0029]
Furthermore, in the embodiment described above, the case where a single refrigerant such as HCFC22 (abbreviation of hydrochlorofluorocarbon 22) often used in an air conditioner has been described. Recently, however, research on alternative refrigerants to replace HCFC 22 has been active from the viewpoint of ozone layer destruction and global warming, and the use of mixed refrigerants as well as single refrigerants has been studied as alternative refrigerants. On the other hand, it is clear that the structure, cycle configuration, and operation control method of the indoor unit described in the embodiments shown in FIGS. 1 and 2 can be applied, and similar effects can be obtained.
[0030]
As described above, according to the present embodiment, in order to provide a sufficiently large heat exchanger in a compact indoor unit, the indoor heat exchanger is multi-stage bent or curved and at the same time provided from the front to the back of the indoor unit. Furthermore, the indoor heat exchanger is provided with a dehumidification control valve that thermally divides the indoor unit from the lower front part of the indoor unit and the front part from the front part to the rear part or the front part and the rear part and performs the throttling action during the dehumidifying operation between them. During the dehumidifying operation, the indoor heat exchanger has a refrigeration cycle configuration in which the lower front portion or the rear portion of the indoor heat exchanger is a cooler, and the upper front portion to the rear portion or the front portion is a heater. As a result, even in a compact indoor unit, the performance in cooling and heating operation is sufficiently improved to save power, and in the dehumidifying operation, the dehumidifying efficiency (dehumidifying amount / power consumption) is improved and dehumidified water generated in the cooler So that it does not re-evaporate on the heater.
[0031]
In addition, each refrigerant flow path of the indoor heat exchanger divided into two is divided into two or more systems to prevent an increase in the flow resistance of the refrigerant flow in the indoor heat exchanger provided from the front to the back of the indoor unit. In addition, the outlet part of the refrigerant flow path of the indoor heat exchanger can be integrated into one system so that sufficient refrigerant subcooling can be obtained during the heating operation, and furthermore, the refrigerant flow and air flow in the indoor heat exchanger can be as much as possible. By adopting a piping configuration that provides an opposing flow, it is possible to prevent a decrease in performance due to a larger heat exchanger and a longer refrigerant flow path or a dehumidification control valve.
[0032]
In addition, the capacity of the outdoor fan and the compressor can be controlled, and the capacity of these devices is appropriately controlled so that the heating amount in the heater can be controlled in a wide range so that the amount of dehumidified water can be taken sufficiently. At the same time as performing dehumidifying operation with a slight taste, isothermal feeling, and cooling feeling, it is possible to perform dehumidifying operations in various usage forms by controlling the capacity of the indoor fan.
[0033]
Furthermore, the above dehumidifying operation method and the piping configuration of the indoor heat exchanger can be applied regardless of a single refrigerant or a mixed refrigerant, and the same effect can be obtained.
[Brief description of the drawings]
[0034]
FIG. 1 is a diagram showing an indoor unit structure of an air conditioner according to an embodiment of the present invention.
FIG. 2 is a diagram showing the structure and operating state of the dehumidification control valve in FIG.
FIG. 3 is a diagram showing a cycle configuration of an air conditioner according to an embodiment of the present invention.
FIG. 4 is a diagram showing a piping configuration of an indoor heat exchanger that is another embodiment of the present invention.
FIG. 5 is a diagram showing the shape of an indoor heat exchanger according to another embodiment of the present invention.
FIG. 6 is a diagram showing the shape of an indoor heat exchanger according to still another embodiment of the present invention.
[Explanation of symbols]
[0035]
DESCRIPTION OF SYMBOLS 1 ... Indoor heat exchanger, 2, 2 '... Lower front part of indoor heat exchanger, 3 ... Upper front part of indoor heat exchanger, 4 ... Rear part of indoor heat exchanger, 5 ... Dehumidification control valve, 7 ... Connection pipe between indoor heat exchanger and dehumidification control valve, 9 ... Indoor fan, 10 ... Front suction grill, 11 ... Upper suction grill, 12 ... Rear suction grill, 13 ... Filter, 14 ... Rear casing, 15 ... Outlet Mouth, 16 ... Outlet wind direction plate, 17 ... Front dew tray, 18 ... Back dew tray, 20 ... Heat transfer tube, 21, 22 ... Connection pipe of heat transfer tube, 23 ... Radiation fin, 24, 63, 67 ... Thermal cutting line,
DESCRIPTION OF SYMBOLS 30 ... Valve body, 31 ... Valve seat, 32 ... Valve body, 33 ... Valve part, 34, 35 ... Connection pipe, 36 ... Electromagnetic motor, 37 ... Refrigerant flow path at the time of dehumidification operation, 50 ... Compressor, 51 ... Four-way Valve, 52 ... Outdoor heat exchanger, 53 ... Electric expansion valve, 54, 55, 56, 57, 60, 61, 62 ... Refrigerant flow path, 58 ... Outdoor fan, 59 ... Indoor air flow direction, 64, 65, 66 , 68, 69 ... Heat exchanger part.

Claims

The indoor heat exchanger provided in the indoor unit has a refrigeration cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger are connected by piping . A first indoor heat exchange part having a plurality of refrigerant flow paths serving as a heater and a second indoor heat exchange part having a plurality of refrigerant flow paths serving as a cooler during a dehumidifying operation , An expansion mechanism that is provided in a refrigerant flow path between the first indoor heat exchange portion and the second indoor heat exchange portion and acts as a throttle during the dehumidifying operation, and downstream of the indoor heat exchanger in the air flow direction In an air conditioner equipped with an indoor fan arranged in
The indoor heat exchanger has a structure having an upper part and a lower part,
The upper part is the first indoor heat exchange part, the lower part is the second indoor heat exchange part,
During the heating operation, the refrigerant passages of the plurality of systems are configured such that the inlet side through which the gas refrigerant flows in the second indoor heat exchange portion is arranged on the leeward side of the air flow, and in the first indoor heat exchange portion, The refrigerant flow path is configured so that the refrigerant outlet side during heating operation becomes a single refrigerant flow path from the multiple refrigerant flow paths, and the one refrigerant flow path is arranged on the windward side Air conditioner.