JP2004044948A

JP2004044948A - Air conditioner

Info

Publication number: JP2004044948A
Application number: JP2002204535A
Authority: JP
Inventors: Yukio Watanabe; 渡邊　幸男; Yoshikazu Kawabe; 川邉　義和; Tomoaki Ando; 安藤　智朗
Original assignee: Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Holdings Corp
Priority date: 2002-07-12
Filing date: 2002-07-12
Publication date: 2004-02-12
Anticipated expiration: 2022-07-12
Also published as: JP4226284B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner for assuring the sufficient heating performance by reducing the loss in heat radiation and improving the economical efficiency and amenity without giving the sense of discomfort, by combing the air conditioning methods of different temperature levels with a comparatively simple cycle constitution. <P>SOLUTION: A plurality of throttling devices 14, 18, 28 are mounted in the refrigerant pipe connecting an outdoor unit 2, an indoor unit 6 and an intermediate unit 4, and the parallel connection or serial connection of a first utilization-side heat exchanger 12 and an intermediate heat exchanger 16 can be selected by controlling an opening of the plurality of throttling devices 14, 18, 28 in heating operation. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、ヒートポンプサイクルを採用した空気調和機に関し、特に快適性を向上するために、異なる温度レベルに制御できる複数の利用側熱交換器を有する空気調和機に関する。
【０００２】
【従来の技術】
冷凍サイクルを用いた最近の空気調和機は、暖房運転及び冷房運転が可能で、年間を通して空調機として使用できるヒートポンプ式が主流であるが、快適性向上のために利用側熱交換器を複数にして、暖房運転時において床暖房を可能にしたサイクル構成が提案されている。
【０００３】
例えば、特開平５−２８８４２８号公報に記載の空気調和機は、図３に示されるように、室内に第１利用側熱交換器１００と第２利用側熱交換器１０２とを有し、圧縮機１０４、第１利用側熱交換器１００、第１絞り装置１０６、冷媒と第２媒体を熱交換させるための中間熱交換器１０８、第２絞り装置１１０、熱源側熱交換器１１２を順次接続して冷媒を循環させるサイクルを構成している。また、流量調整弁１１４を設けた配管１１６を第１利用側熱交換器１００をバイパスするように接続し、中間熱交換器１０８を介して第２利用側熱交換器１０２を接続して、第２利用側熱交換器１０２に第２媒体を循環させるように配管して暖房、冷房、除湿時の快適性向上及び効率の向上を図っている。
【０００４】
【発明が解決しようとする課題】
しかしながら、上記従来の構成では、運転モードに関係なく、常時冷媒が中間熱交換器１０８を通過するため、第１利用側熱交換器１００と熱源側熱交換器１１２のみを用いた場合の効率の低下が大きい。また、第１利用側熱交換器１００と中間熱交換器１０８が直列に接続されているため、暖房運転時に第１利用側熱交換器１００での放熱ロスが発生し、第２利用側熱交換器１０２の温度が十分に上がらない。したがって、十分な輻射暖房性能が得られず、暖房能力が不足し、不快感を感じるという問題があった。
【０００５】
本発明は、従来技術の有するこのような問題点に鑑みてなされたものであり、比較的簡単なサイクル構成で異なる温度レベルを持つ空調方式を複合することにより、放熱ロスを減少させて十分な暖房性能を確保するとともに、不快感を感じることのない経済性及び快適性の向上した空気調和機を安価に提供することを目的としている。
【０００６】
また、本発明の別の目的は、室外機と室内機からなる既存の空気調和機を大幅に変更することなく、第２媒体を加熱するための中間ユニットを容易に取り付けて床暖房あるいは給湯を可能にした空気調和機を提供することである。
【０００７】
【課題を解決するための手段】
上記目的を達成するために、本発明のうちで請求項１に記載の発明は、熱源側熱交換器を有する室外ユニットと、第１利用側熱交換器を有し冷媒を用いて空調を行う室内ユニットと、冷媒と第２媒体を熱交換させるための中間熱交換器を有し冷媒により第２媒体を加熱する中間ユニットとを備えた空気調和機において、上記室外ユニット、室内ユニット及び中間ユニットを互いに接続する冷媒配管に複数の絞り装置を設け、暖房運転時に、該複数の絞り装置の開度を制御することにより上記第１利用側熱交換器及び上記中間熱交換器の並列接続及び直列接続を選択できるようにしたことを特徴とする。
【０００８】
また、請求項２に記載の発明は、上記複数の絞り装置が第１、第２及び第３絞り装置を含み、上記室外ユニットに設けられた圧縮機、上記第１利用側熱交換器、上記第１絞り装置、上記中間熱交換器、上記第２絞り装置、上記熱源側熱交換器を順次接続して冷媒を循環させるサイクルを構成するとともに、上記第３絞り装置を有する配管を上記第１絞り装置と上記中間熱交換器をバイパスするように接続し、さらに開閉弁を有する配管で上記圧縮機と上記第１利用側熱交換器を接続する配管と、上記第１絞り装置と上記中間熱交換器を接続する配管を接続し、上記中間熱交換器を介して第２利用側熱交換器を接続して該第２利用側熱交換器に第２媒体を循環させるようにしたことを特徴とする。
【０００９】
さらに、請求項３に記載の発明は、上記複数の絞り装置が第１、第２、第３及び第４絞り装置を含み、上記室外ユニットに設けられた圧縮機、上記第１利用側熱交換器、上記第１絞り装置、上記中間熱交換器、上記第４絞り装置、上記第２絞り装置、上記熱源側熱交換器を順次接続して冷媒を循環させるサイクルを構成するとともに、上記第３絞り装置を有する配管を上記第１絞り装置と上記中間熱交換器と上記第４絞り装置をバイパスするように接続し、さらに開閉弁を有する配管で上記圧縮機と上記第１利用側熱交換器を接続する配管と、上記第１絞り装置と上記中間熱交換器を接続する配管を接続し、上記中間熱交換器を介して第２利用側熱交換器を接続して該第２利用側熱交換器に第２媒体を循環させるようにしたことを特徴とする。
【００１０】
また、請求項４に記載の発明は、暖房起動時に、上記中間熱交換器と上記第１利用側熱交換器に直列に冷媒を流すようにしたことを特徴とする。
【００１１】
また、請求項５に記載の発明は、暖房運転時に、上記中間熱交換器と上記第１利用側熱交換器に並列に冷媒を流すようにしたことを特徴とする。
【００１２】
また、請求項６に記載の発明は、冷房運転時に、上記第１利用側熱交換器を冷却用に、上記中間熱交換器を加熱用に使用するようにしたことを特徴とする。
【００１３】
また、請求項７に記載の発明は、上記室外ユニットの制御を行う室外ユニット制御部と上記室内ユニットの制御を行う室内ユニット制御部とが、上記中間ユニットの制御を行う中間ユニット制御部を介して通信を行うことを特徴とする。
【００１４】
【作用】
上記のように構成したので、例えば、第１利用側熱交換器を通常の気流空調ユニットとして、第２利用側熱交換器を床暖房ユニットとして使用することができる。
【００１５】
暖房運転起動時においては、第１利用側熱交換器と中間熱交換器を直列に使用する回路構成にし、中間ユニット制御部が必要に応じて室外ユニットに対して第２利用側熱交換器で使用する熱量を加えた要求信号を送り、第２媒体を循環させることにより中間熱交換器を介して第２利用側熱交換器を利用することができる。
【００１６】
通常暖房運転時においては、第１利用側熱交換器と中間熱交換器を並列に使用する回路構成にし、中間ユニット内に設けた第１利用側熱交換器及び中間熱交換器の下流側に位置する絞り装置を用いて利用側熱量を分配し、必要な熱量は室内ユニットからの信号と中間ユニット内の信号を元に中間ユニット制御部が計算して室外ユニットに要求信号を送り、室外ユニットは圧縮機周波数及び絞り装置を制御して必要熱量を発生させる。このようにして第１利用側熱交換器あるいは第２利用側熱交換器の温度を任意に設定可能な暖房運転が可能になる。
【００１７】
一方、冷房運転時においては、中間熱交換器を使用しない通常の冷房運転に加えて、低負荷条件など、必要に応じて中間熱交換器と第１利用側熱交換器を直列に接続した回路構成として、室外ユニット内は絞り装置を全開にした冷房動作（再熱除湿運転モード）を行うことができる。この時、中間熱交換器を凝縮器として用いるために、中間熱交換器の下流側（第１利用側熱交換器の上流側）に位置する中間ユニット内の絞り装置を制御すると同時に、第２媒体を循環させ第２利用側熱交換器から放熱することにより冷房運転時の快適性を向上することができる。
【００１８】
【発明の実施の形態】
以下、本発明の実施の形態について、図面を参照しながら説明する。
実施の形態１．
図１は本発明にかかる空気調和機の実施の形態１を示しており、冷媒配管により互いに接続された室外ユニット２と、中間ユニット４と、室内ユニット６とにより冷媒回路が構成されている。
【００１９】
図１に示されるように、冷媒（一次冷媒）を圧縮するための圧縮機８と、冷媒の循環方向を切り替えるための四方弁１０と、室内空気と冷媒との熱交換を行う第１利用側熱交換器１２と、両方向流れの絞り制御及び全開状態が可能な第１絞り装置１４と、冷媒と第２媒体との熱交換を行う中間熱交換器１６と、両方向流れの絞り制御が可能な第２絞り装置１８と、室外空気と冷媒との熱交換を行う熱源側熱交換器２０と、圧縮機への液戻りを防止するためのアキュムレータ２２とが環状に接続されている。
【００２０】
また、四方弁１０と第１利用側熱交換器１２の間の冷媒配管と、第１絞り装置１４と中間熱交換器１６の間の冷媒配管とは、開閉弁２４が取り付けられた第１バイパス管２６により接続されており、第１バイパス管２６は第１利用側熱交換器１２と第１絞り装置１４をバイパスする冷媒路となっている。さらに、第１利用側熱交換器１２と第１絞り装置１４の間の冷媒配管と、中間熱交換器１６と第２絞り装置１８の間の冷媒配管とは、両方向流れの絞り制御及び全開状態が可能な第３絞り装置２８が取り付けられた第２バイパス管３０により接続されており、第２バイパス管３０は第１絞り装置１４と中間熱交換器１６とをバイパスする冷媒路となっている。
【００２１】
また、第２利用側熱交換器３２と、ポンプ３４と、リザーブタンク３６は、中間熱交換器１６と配管で接続されており、第２媒体を循環させるサイクルを構成している。すなわち、ヒ−トポンプの冷媒と第２媒体のそれぞれが循環するサイクルを、中間熱交換器１６を介して熱交換させるように組み合わせたサイクル構成である。
【００２２】
また、上述した各機器のうち、圧縮機８、四方弁１０、第２絞り装置１８、熱源側熱交換器２０及びアキュムレータ２２は室外ユニット２に設けられるとともに、第１利用側熱交換器１２は室内ユニット６に設けられている。
【００２３】
さらに、第１絞り装置１４、中間熱交換器１６、開閉弁２４を有する第１バイパス管２６、第３絞り装置２８を有する第２バイパス管３０を含む冷媒回路と、中間熱交換器１６、ポンプ３４、リザーブタンク３６から構成される第２媒体回路は中間ユニット４に設けられ、室外ユニット２及び室内ユニット６と着脱自在に接続されている。
【００２４】
また、中間ユニット４を制御する中間ユニット制御部３８を介して、室内ユニット６を制御する室内ユニット制御部４０と室外ユニット２を制御する室外ユニット制御部４２とを結ぶ通信経路４４が形成されている。
【００２５】
上記構成の本発明にかかる空気調和機の動作について以下説明する。ここでは、第１利用側熱交換器１２として室内空気と熱交換する気流熱交換器を、第２利用側熱交換器３２としてパイプが組み込まれた床暖房マットを、第２媒体として水を、それぞれ使用した場合を例にとり説明する。
【００２６】
まず、暖房運転時の動作について説明する。
起動時は、開閉弁２４及び第３絞り装置２８を閉じ、第１絞り装置１４を全開の状態で気流熱交換器１２と中間熱交換器１６を直列に接続した回路で起動する。室内ユニット６及び室外ユニット２は通信経路４４を介して通信をしながら、あらかじめ定められた動作を行う。この制御内容は、中間ユニット４がない場合の制御パターンであり、気流熱交換器１２はリモコンなどにより所望の温度になるように室内空気を暖める。
【００２７】
この時、室内ユニット６及び室外ユニット２間の通信内容は中間ユニット制御部３８で参照することが可能である、中間ユニット４は中間熱交換器１６の出口配管部など中間ユニット４内部に設けたセンサーの情報を元に利用側熱交換器で必要な熱量を計算し、信号内容を変更する。すなわち、室内ユニット６から送られる要求熱量に中間ユニット４で必要な熱量を追加して、新たに設定した要求熱量に対応する信号に通信内容を修正して室外ユニット２に送る。信号を受けた室外ユニット２は要求に応じた能力を出すべく第２絞り装置１８の弁開度、圧縮機周波数などを制御する。中間ユニット４は必要に応じてポンプ３４を運転し、中間熱交換器１６で得た熱量は床暖房マットを利用した暖房熱量に消費される。
【００２８】
上記説明では、暖房運転起動時は気流熱交換器１２と中間熱交換器１６を直列に接続して使用する方法を述べたが、並列に構成した回路で起動しても問題はない。
【００２９】
室温が上昇し設定温度に近づくと、より少ない熱量で暖房感が得られるように省エネ運転が可能な床暖房優先の運転に切替える。
【００３０】
床暖房優先運転時は、開閉弁２４を開き、第１絞り装置１４を全閉にして、冷凍サイクルを中間熱交換器１６と気流熱交換器１２が完全に並列に使用されるサイクルに設定する。この場合も、室外ユニット２は中間ユニット制御部３８を経由して与えられる修正された指示信号に従って、要求に応じた能力を出すべく第２絞り装置１８の弁開度、圧縮機周波数などを制御する。床温度は、水循環量の制御あるいは第３絞り装置２８の開度制御により調整される。さらに、床温度を高くしたい場合には、第３絞り装置２８を全閉にすると気流熱交換器１２での放熱ロスを抑えられるため、室外ユニット２で得られた熱量はすべて中間熱交換器１６を経由して水回路側に与えられ床暖房で使用される。このため、中間ユニット制御部３８の制御により床温度を任意に設定することが可能となる。
【００３１】
次に、冷房運転時の動作について説明する。
冷房運転時は、四方弁１０を切替えると共に、第１絞り装置１４及び開閉弁２４を共に全閉にし、第３絞り装置２８を全開にすると、中間ユニット４のない通常のエアコンと同様の回路構成となり、一般のエアコンと同様の気流のみを用いた冷房動作になる。
【００３２】
近年冷房の普及と共に、気流での冷房運転中に冷気が下方に滞留し、足元が冷えて不快感があるという意見も聞かれる。本発明にかかる冷凍サイクルでは、気流冷房を行いながら床暖房を行い、床面の温度の下がり過ぎを防止するためのハイブリッド運転を行うことができる。
【００３３】
次に、ハイブリッド運転時の動作を説明する。
ハイブリッド運転時は、四方弁１０は冷房位置に設定し、第２絞り装置１８を全開に、第３絞り装置２８は全閉にするとともに、第１絞り装置１４を適当に絞って運転する。このときの室外ユニット２の制御内容は中間ユニット４のない場合の再熱除湿モードに相当する（再熱除湿モードは、室内の気流熱交換器を２分割して中間に絞り機構を設け、上流部分を凝縮器、下流部分を蒸発器として用いるものである）。すなわち、ハイブリッド運転を行う場合は、中間ユニット制御部３８は、室外ユニット制御部４２に再熱除湿運転の指示信号を送る一方、室内ユニット制御部４０に冷房運転の指示信号を送り、中間ユニット制御部３８が、室内ユニット制御部４０及び室外ユニット制御部４２から得た情報と、中間熱交換器１６の出口配管部など中間ユニット４内部に設けたセンサーの情報を元に第１絞り装置１４を制御する。このようにして、床温度の下がりすぎを抑えつつ気流による冷房運転を行うことが可能となる。
【００３４】
上述したように、室外ユニット２の運転制御は、中間ユニット４の有無に関係なく、何ら変更を加えることなく行うことができるので、中間ユニット４を取り外して室外ユニット２及び室内ユニット６からなる通常のシステムとして機能する。逆に、中間ユニット４は何ら変更することなく通常のエアコンに接続することもできるので、組み合わせの自由度が高い。
【００３５】
実施の形態２．
図２は本発明にかかる空気調和機の実施の形態２を示しており、図１に示される実施の形態１において、第２絞り装置１８と第３絞り装置２８の間の冷媒配管と中間熱交換器１６とを接続する冷媒配管に第４絞り装置４６を設けたものであり、第２バイパス管３０は、第１絞り装置１４と中間熱交換器１６と第４絞り装置４６をバイパスするように接続されている。
【００３６】
したがって、第１絞り装置１４、中間熱交換器１６、開閉弁２４を有する第１バイパス管２６、第３絞り装置２８を有する第２バイパス管３０、第４絞り装置４６を含む冷媒回路と、中間熱交換器１６、ポンプ３４、リザーブタンク３６から構成される第２媒体回路は中間ユニット４に設けられ、室外ユニット２及び室内ユニット６と着脱自在に接続されている。
【００３７】
上記構成の本発明にかかる空気調和機の動作について以下説明する。ここでも、実施の形態１と同様、第１利用側熱交換器１２として室内空気と熱交換する気流熱交換器を、第２利用側熱交換器３２としてパイプが組み込まれた床暖房マットを、第２媒体として水を、それぞれ使用した場合を例にとり説明する。
【００３８】
まず、暖房運転時の動作について説明する。
起動時は、開閉弁２４及び第３絞り装置２８を閉じ、第１絞り装置１４及び第４絞り装置４６を全開の状態で気流熱交換器１２と中間熱交換器１６を直列に接続した回路で起動する。室内ユニット６及び室外ユニット２は通信経路４４を介して通信をしながら、あらかじめ定められた動作を行う。この制御内容は、中間ユニット４がない場合の制御パターンであり、気流熱交換器１２はリモコンなどにより所望の温度になるように室内空気を暖める。
【００３９】
この時、室内ユニット６及び室外ユニット２間の通信内容は中間ユニット制御部３８で参照することが可能である、中間ユニット４は中間熱交換器１６の出口配管部など中間ユニット４内部に設けたセンサーの情報を元に利用側熱交換器で必要な熱量を計算し、信号内容を変更する。すなわち、室内ユニット６から送られる要求熱量に中間ユニット４で必要な熱量を追加して、新たに設定した要求熱量に対応する信号に通信内容を修正して室外ユニット２に送る。信号を受けた室外ユニット２は要求に応じた能力を出すべく第２絞り装置１８の弁開度、圧縮機周波数などを制御する。中間ユニット４は必要に応じてポンプ３４を運転し、中間熱交換器１６で得た熱量は床暖房マットを利用した暖房熱量に消費される。
【００４０】
上記説明では、暖房運転起動時は気流熱交換器１２と中間熱交換器１６を直列に接続して使用する方法を述べたが、並列に構成した回路で起動しても問題はない。
【００４１】
室温が上昇し設定温度に近づくと、より少ない熱量で暖房感が得られるように省エネ運転が可能な床暖房優先の運転に切替える。
【００４２】
床暖房優先運転時は、開閉弁２４を開き、第１絞り装置１４を全閉にするとともに、第３絞り装置２８及び第４絞り装置４６を適当に開いて、冷凍サイクルを中間熱交換器１６と気流熱交換器１２が完全に並列に使用されるサイクルに設定する。この場合も、室外ユニット２は中間ユニット制御部３８を経由して与えられる修正された指示信号に従って、要求に応じた能力を出すべく第２絞り装置１８の弁開度、圧縮機周波数などを制御する。床温度は、水循環量の制御あるいは第３及び第４絞り装置２８，４６の開度制御により調整される。さらに、床温度を高くしたい場合には、第３絞り装置２８を全閉にすると気流熱交換器１２での放熱ロスを抑えられるため、室外ユニット２で得られた熱量はすべて中間熱交換器１６を経由して水回路側に与えられ床暖房で使用される。さらに、第４絞り装置４６をやや絞ると冷媒の凝縮温度を高くすることも可能である。このため、中間ユニット制御部３８の制御により床温度を任意に設定することが可能となる。
また、実施の形態１に比較し、第４絞り装置４６により細かい能力調整が可能となる。
【００４３】
次に、冷房運転時の動作について説明する。
冷房運転時は、四方弁１０を切替えると共に、第１絞り装置１４、開閉弁２４及び第４絞り装置４６をすべて全閉にし、第３絞り装置２８を全開にすると、中間ユニット４のない通常のエアコンと同様の回路構成となり、一般のエアコンと同様の気流のみを用いた冷房動作になる。
【００４４】
次に、ハイブリッド運転時の動作を説明する。
ハイブリッド運転時は、四方弁１０は冷房位置に設定し、第２絞り装置１８及び第４絞り装置４６を共に全開に、第３絞り装置２８は全閉にするとともに、第１絞り装置１４を適当に絞って運転する。このときの室外ユニット２の制御内容は中間ユニット４のない場合の再熱除湿モードに相当する。すなわち、ハイブリッド運転を行う場合は、中間ユニット制御部３８は、室外ユニット制御部４２に再熱除湿運転の指示信号を送る一方、室内ユニット制御部４０に冷房運転の指示信号を送り、中間ユニット制御部３８が、室内ユニット制御部４０及び室外ユニット制御部４２から得た情報と、中間熱交換器１６の出口配管部など中間ユニット４内部に設けたセンサーの情報を元に第１絞り装置１４及び第４絞り装置４６を制御する。このようにして、床温度の下がりすぎを抑えつつ気流による冷房運転を行うことが可能となる。
【００４５】
なお、上記実施の形態では、室外ユニット２に新たなセンサーを追加しない場合を示したが、通信経路から得られる情報が不十分な場合、吐出温度センサーなどを追加して中間ユニット制御部３８に接続しても良い。
【００４６】
また、上記実施の形態においては、冷媒としてＨＦＣ冷媒（例えばＲ４１０ＡやＲ３２）やＨＣＦＣ冷媒（例えばＲ２２）等の亜臨界冷媒が使用されるが、ＣＯ_２等の超臨界冷媒を使用することもできる。すなわち、超臨界サイクルにおいては、高い第２媒体温度を得るためには、圧力を上げるのが有効であり、限られた範囲の圧縮機運転周波数内において異なる温度の出力を実現することができる。
【００４７】
さらに、上記実施の形態においては、第２利用側熱交換器３２を床暖房マットとして説明したが、第２利用側熱交換器３２は温水暖房用熱交換器あるいは給湯器であってもよく、第２媒体としては水以外にブライン（不凍液）を使用することも可能である。
【００４８】
【発明の効果】
本発明は、以上説明したように構成されているので、以下に記載されるような効果を奏する。
本発明によれば、室外ユニット、室内ユニット及び中間ユニットを互いに接続する冷媒配管に複数の絞り装置を設け、暖房運転時に、複数の絞り装置の開度を制御することにより第１利用側熱交換器及び中間熱交換器の並列接続及び直列接続を選択できるようにしたので、必要に応じ第１利用側熱交換器及び中間熱交換器を並列あるいは直列にして使用することができるので、例えば暖房運転時の放熱ロスを抑えることができ、経済性及び快適性の向上した空気調和機を安価に提供することができる。
【００４９】
また、冷房運転時に、第１利用側熱交換器を冷却用に、中間熱交換器を加熱用に使用するようにしたので、気流による室温制御と輻射による足元の冷えすぎ防止を独立して高精度に制御することができる。したがって、例えば冷房時に不快感を感じることがなく個人の嗜好を反映したより快適性の高い空気調和機を安価に実現することができる。
【００５０】
さらに、室外ユニットの制御を行う室外ユニット制御部と室内ユニットの制御を行う室内ユニット制御部とが、中間ユニットの制御を行う中間ユニット制御部を介して通信を行うようにしたので、例えば従来の室内ユニットと室外ユニットの中間に、中間熱交換器を含む中間ユニットを追加装備するだけで従来ユニットの制御を変更することなく使用することができ、２つの利用側熱交換器を個別に制御する快適性の高い空気調和機を安価に提供することができる。
【図面の簡単な説明】
【図１】本発明にかかる空気調和機の実施の形態１を示すサイクル構成図である。
【図２】本発明にかかる空気調和機の実施の形態２を示すサイクル構成図である。
【図３】従来の空気調和機を示すサイクル構成図である。
【符号の説明】
２　室外ユニット、　４　中間ユニット、　６　室内ユニット、　８　圧縮機、１０　四方弁、　１２　第１利用側熱交換器、　１４　第１絞り装置、
１６　中間熱交換器、　１８　第２絞り装置、２０　熱源側熱交換器、
２２　アキュムレータ、　２４　開閉弁、　２６　第１バイパス管、
２８　第３絞り装置、　３０　第２バイパス管、　３２　第２利用側熱交換器、３４　ポンプ、　３６　リザーブタンク、　３８　中間ユニット制御部、
４０　室内ユニット制御部、　４２　室外ユニット制御部、　４４　通信経路、４６　第４絞り装置。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an air conditioner that employs a heat pump cycle, and more particularly to an air conditioner that has a plurality of use-side heat exchangers that can be controlled at different temperature levels to improve comfort.
[0002]
[Prior art]
Most air conditioners using a refrigeration cycle can perform heating operation and cooling operation, and the mainstream is a heat pump type that can be used as an air conditioner throughout the year.However, in order to improve comfort, there are multiple use-side heat exchangers. Thus, a cycle configuration that enables floor heating during a heating operation has been proposed.
[0003]
For example, the air conditioner described in Japanese Patent Application Laid-Open No. 5-288428 has a first use side heat exchanger 100 and a second use side heat exchanger 102 in a room as shown in FIG. Machine 104, first use side heat exchanger 100, first expansion device 106, intermediate heat exchanger 108 for exchanging heat between the refrigerant and the second medium, second expansion device 110, and heat source side heat exchanger 112 are sequentially connected. And circulates the refrigerant. Further, the pipe 116 provided with the flow rate regulating valve 114 is connected so as to bypass the first use side heat exchanger 100, and the second use side heat exchanger 102 is connected through the intermediate heat exchanger 108, A pipe is circulated through the second use side heat exchanger 102 so as to circulate the second medium, thereby improving comfort and efficiency during heating, cooling, and dehumidification.
[0004]
[Problems to be solved by the invention]
However, in the above-described conventional configuration, since the refrigerant always passes through the intermediate heat exchanger 108 regardless of the operation mode, the efficiency in the case of using only the first usage-side heat exchanger 100 and the heat-source-side heat exchanger 112 is reduced. The drop is large. Further, since the first use side heat exchanger 100 and the intermediate heat exchanger 108 are connected in series, a heat dissipation loss occurs in the first use side heat exchanger 100 during the heating operation, and the second use side heat exchange occurs. The temperature of the vessel 102 does not rise sufficiently. Therefore, there has been a problem that sufficient radiation heating performance cannot be obtained, the heating capacity is insufficient, and discomfort is felt.
[0005]
The present invention has been made in view of such problems of the related art, and by combining air conditioning systems having different temperature levels with a relatively simple cycle configuration, it is possible to sufficiently reduce heat dissipation loss and An object of the present invention is to provide an inexpensive air conditioner that ensures heating performance and has improved economy and comfort without feeling uncomfortable.
[0006]
Another object of the present invention is to easily install an intermediate unit for heating the second medium to perform floor heating or hot water supply without largely changing an existing air conditioner including an outdoor unit and an indoor unit. It is to provide an air conditioner that has been made possible.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, an invention according to claim 1 of the present invention performs air conditioning using an outdoor unit having a heat source side heat exchanger and a refrigerant having a first use side heat exchanger. In the air conditioner including an indoor unit and an intermediate unit having an intermediate heat exchanger for exchanging heat between the refrigerant and the second medium and heating the second medium with the refrigerant, the outdoor unit, the indoor unit, and the intermediate unit A plurality of throttle devices are provided in a refrigerant pipe connecting the first heat exchanger and the intermediate heat exchanger in parallel and in series during heating operation by controlling the degree of opening of the plurality of throttle devices. The connection is selectable.
[0008]
In the invention described in claim 2, the plurality of expansion devices include first, second, and third expansion devices, and a compressor provided in the outdoor unit, the first use-side heat exchanger, The first expansion device, the intermediate heat exchanger, the second expansion device, and the heat source side heat exchanger are sequentially connected to constitute a cycle for circulating the refrigerant, and the pipe having the third expansion device is connected to the first expansion device. A pipe that connects the expansion device and the intermediate heat exchanger so as to bypass the expansion device, and further connects the compressor and the first use-side heat exchanger with a pipe having an on-off valve; the first expansion device and the intermediate heat exchanger; A pipe connecting the exchanger is connected, a second use side heat exchanger is connected via the intermediate heat exchanger, and the second medium is circulated through the second use side heat exchanger. And
[0009]
Further, in the invention according to claim 3, the plurality of throttle devices include first, second, third, and fourth throttle devices, and the compressor provided in the outdoor unit, the first use-side heat exchange. And the first throttle device, the intermediate heat exchanger, the fourth throttle device, the second throttle device, and the heat source side heat exchanger are sequentially connected to form a cycle for circulating the refrigerant, A pipe having a throttling device is connected so as to bypass the first throttling device, the intermediate heat exchanger, and the fourth throttling device, and the compressor and the first utilization side heat exchanger are further connected by a pipe having an on-off valve. And a pipe connecting the first expansion device and the intermediate heat exchanger, and connecting a second use side heat exchanger via the intermediate heat exchanger to the second use side heat exchanger. The second medium is circulated through the exchanger.
[0010]
The invention described in claim 4 is characterized in that a refrigerant is caused to flow in series between the intermediate heat exchanger and the first use-side heat exchanger when heating is started.
[0011]
The invention according to claim 5 is characterized in that a refrigerant is caused to flow in parallel to the intermediate heat exchanger and the first use-side heat exchanger during a heating operation.
[0012]
The invention according to claim 6 is characterized in that the first use-side heat exchanger is used for cooling and the intermediate heat exchanger is used for heating during a cooling operation.
[0013]
According to a seventh aspect of the present invention, the outdoor unit control unit that controls the outdoor unit and the indoor unit control unit that controls the indoor unit are connected via an intermediate unit control unit that controls the intermediate unit. And perform communication.
[0014]
[Action]
With the above configuration, for example, the first use side heat exchanger can be used as a normal airflow air conditioning unit, and the second use side heat exchanger can be used as a floor heating unit.
[0015]
At the time of the heating operation start, the first use side heat exchanger and the intermediate heat exchanger are configured to be used in series, and the intermediate unit control unit controls the outdoor unit as necessary by using the second use side heat exchanger. By sending a request signal to which the amount of heat to be used is added and circulating the second medium, the second use-side heat exchanger can be used via the intermediate heat exchanger.
[0016]
At the time of normal heating operation, the first use side heat exchanger and the intermediate heat exchanger are used in parallel, and a circuit configuration is used, and the first use side heat exchanger and the intermediate heat exchanger provided in the intermediate unit are located downstream of the first use side heat exchanger and the intermediate heat exchanger. The use side heat amount is distributed using the located expansion device, the required heat amount is calculated by the intermediate unit control unit based on the signal from the indoor unit and the signal in the intermediate unit, and a request signal is sent to the outdoor unit, and the outdoor unit Controls the compressor frequency and the throttling device to generate the required amount of heat. In this way, a heating operation in which the temperature of the first use side heat exchanger or the second use side heat exchanger can be set arbitrarily can be performed.
[0017]
On the other hand, in the cooling operation, in addition to the normal cooling operation not using the intermediate heat exchanger, a circuit in which the intermediate heat exchanger and the first use side heat exchanger are connected in series as necessary, such as in a low load condition. As a configuration, a cooling operation (reheat dehumidification operation mode) in which the expansion device is fully opened can be performed in the outdoor unit. At this time, in order to use the intermediate heat exchanger as a condenser, the throttle device in the intermediate unit located downstream of the intermediate heat exchanger (upstream of the first utilization side heat exchanger) is controlled, By circulating the medium and radiating the heat from the second use-side heat exchanger, the comfort during the cooling operation can be improved.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 shows an air conditioner according to a first embodiment of the present invention, in which an outdoor unit 2, an intermediate unit 4, and an indoor unit 6 connected to each other by a refrigerant pipe constitute a refrigerant circuit.
[0019]
As shown in FIG. 1, a compressor 8 for compressing a refrigerant (primary refrigerant), a four-way valve 10 for switching a circulation direction of the refrigerant, and a first usage side for performing heat exchange between indoor air and the refrigerant A heat exchanger 12, a first throttle device 14 capable of throttle control of a two-way flow and a fully open state, an intermediate heat exchanger 16 performing heat exchange between a refrigerant and a second medium, and a throttle control of a two-way flow are possible. The second expansion device 18, a heat source side heat exchanger 20 for exchanging heat between outdoor air and a refrigerant, and an accumulator 22 for preventing liquid return to the compressor are connected in a ring shape.
[0020]
In addition, the refrigerant pipe between the four-way valve 10 and the first use side heat exchanger 12 and the refrigerant pipe between the first expansion device 14 and the intermediate heat exchanger 16 are connected to the first bypass to which the on-off valve 24 is attached. The first bypass pipe 26 is connected by a pipe 26 and serves as a refrigerant path that bypasses the first use-side heat exchanger 12 and the first expansion device 14. Further, the refrigerant pipe between the first use-side heat exchanger 12 and the first expansion device 14 and the refrigerant pipe between the intermediate heat exchanger 16 and the second expansion device 18 are throttle-controlled in a two-way flow and fully opened. The second bypass pipe 30 is connected by a second bypass pipe 30 to which a third expansion device 28 capable of performing pressure reduction is attached. The second bypass pipe 30 is a refrigerant path that bypasses the first expansion device 14 and the intermediate heat exchanger 16. .
[0021]
The second usage-side heat exchanger 32, the pump 34, and the reserve tank 36 are connected to the intermediate heat exchanger 16 by piping, and constitute a cycle for circulating the second medium. In other words, the cycle configuration is such that the cycle in which the refrigerant of the heat pump and the second medium circulate is combined so that heat is exchanged via the intermediate heat exchanger 16.
[0022]
In addition, among the above-described devices, the compressor 8, the four-way valve 10, the second expansion device 18, the heat source side heat exchanger 20, and the accumulator 22 are provided in the outdoor unit 2, and the first use side heat exchanger 12 is It is provided in the indoor unit 6.
[0023]
Further, a refrigerant circuit including a first expansion device 14, an intermediate heat exchanger 16, a first bypass pipe 26 having an on-off valve 24, and a second bypass tube 30 having a third expansion device 28, an intermediate heat exchanger 16, a pump A second medium circuit including a storage tank and a reserve tank is provided in the intermediate unit 4 and is detachably connected to the outdoor unit 2 and the indoor unit 6.
[0024]
In addition, a communication path 44 connecting an indoor unit control unit 40 for controlling the indoor unit 6 and an outdoor unit control unit 42 for controlling the outdoor unit 2 is formed via an intermediate unit control unit 38 for controlling the intermediate unit 4. I have.
[0025]
The operation of the air conditioner having the above configuration according to the present invention will be described below. Here, an airflow heat exchanger that exchanges heat with room air is used as the first use side heat exchanger 12, a floor heating mat in which pipes are incorporated is used as the second use side heat exchanger 32, and water is used as the second medium. The case where each is used will be described as an example.
[0026]
First, the operation during the heating operation will be described.
At the time of startup, the air-flow heat exchanger 12 and the intermediate heat exchanger 16 are started up in a circuit in which the on-off valve 24 and the third expansion device 28 are closed, and the first expansion device 14 is fully opened. The indoor unit 6 and the outdoor unit 2 perform a predetermined operation while communicating via the communication path 44. This control content is a control pattern when the intermediate unit 4 is not provided, and the airflow heat exchanger 12 warms room air to a desired temperature by a remote controller or the like.
[0027]
At this time, the contents of communication between the indoor unit 6 and the outdoor unit 2 can be referred to by the intermediate unit control unit 38. The intermediate unit 4 is provided inside the intermediate unit 4 such as the outlet pipe of the intermediate heat exchanger 16. Calculate the amount of heat required in the use side heat exchanger based on sensor information and change the signal content. That is, the amount of heat required in the intermediate unit 4 is added to the required amount of heat sent from the indoor unit 6, the communication content is corrected to a signal corresponding to the newly set required amount of heat, and the signal is sent to the outdoor unit 2. The outdoor unit 2 that has received the signal controls the valve opening degree of the second expansion device 18, the compressor frequency, and the like so as to provide the capability according to the request. The intermediate unit 4 operates the pump 34 as necessary, and the amount of heat obtained by the intermediate heat exchanger 16 is consumed by the heating heat using the floor heating mat.
[0028]
In the above description, the method of connecting and using the airflow heat exchanger 12 and the intermediate heat exchanger 16 in series at the time of starting the heating operation has been described. However, there is no problem if the airflow heat exchanger 12 and the intermediate heat exchanger 16 are started up in a circuit configured in parallel.
[0029]
When the room temperature rises and approaches the set temperature, the operation mode is switched to a floor heating-priority operation in which energy saving operation can be performed so that a feeling of heating can be obtained with a smaller amount of heat.
[0030]
During the floor heating priority operation, the on-off valve 24 is opened, the first expansion device 14 is fully closed, and the refrigeration cycle is set to a cycle in which the intermediate heat exchanger 16 and the airflow heat exchanger 12 are used completely in parallel. . Also in this case, the outdoor unit 2 controls the valve opening degree, the compressor frequency, and the like of the second expansion device 18 in accordance with the corrected instruction signal given via the intermediate unit control unit 38 so as to provide the required performance. I do. The bed temperature is adjusted by controlling the amount of water circulation or controlling the opening of the third expansion device 28. Further, when the floor temperature is desired to be raised, since the radiation loss in the airflow heat exchanger 12 can be suppressed by fully closing the third expansion device 28, all the heat quantity obtained in the outdoor unit 2 is reduced by the intermediate heat exchanger 16 It is given to the water circuit side via and used for floor heating. Therefore, it is possible to arbitrarily set the floor temperature under the control of the intermediate unit control unit 38.
[0031]
Next, the operation during the cooling operation will be described.
During the cooling operation, the four-way valve 10 is switched, the first throttle device 14 and the on-off valve 24 are both fully closed, and the third throttle device 28 is fully opened. Thus, a cooling operation using only an airflow similar to a general air conditioner is performed.
[0032]
In recent years, with the spread of cooling, it has been heard that cold air stays downward during the cooling operation in the airflow, and that the feet cool down and cause discomfort. In the refrigeration cycle according to the present invention, floor heating is performed while airflow cooling is performed, and hybrid operation for preventing the temperature of the floor from excessively lowering can be performed.
[0033]
Next, the operation during hybrid operation will be described.
During the hybrid operation, the four-way valve 10 is set to the cooling position, the second expansion device 18 is fully opened, the third expansion device 28 is fully closed, and the first expansion device 14 is appropriately throttled for operation. At this time, the control content of the outdoor unit 2 corresponds to the reheat dehumidification mode without the intermediate unit 4 (the reheat dehumidification mode divides the indoor airflow heat exchanger into two parts, provides a throttle mechanism in the middle, and Part is used as a condenser and the downstream part is used as an evaporator). That is, when performing the hybrid operation, the intermediate unit control unit 38 sends an instruction signal of the reheating and dehumidification operation to the outdoor unit control unit 42, and sends an instruction signal of the cooling operation to the indoor unit control unit 40, thereby controlling the intermediate unit control. The unit 38 controls the first throttle device 14 based on information obtained from the indoor unit control unit 40 and the outdoor unit control unit 42 and information on sensors provided inside the intermediate unit 4 such as the outlet piping of the intermediate heat exchanger 16. Control. In this way, it becomes possible to perform the cooling operation by the airflow while suppressing the floor temperature from dropping too much.
[0034]
As described above, since the operation control of the outdoor unit 2 can be performed without any change irrespective of the presence or absence of the intermediate unit 4, the intermediate unit 4 is removed, and the normal operation including the outdoor unit 2 and the indoor unit 6 is performed. Function as a system. Conversely, since the intermediate unit 4 can be connected to a normal air conditioner without any change, the degree of freedom of combination is high.
[0035]
Embodiment 2 FIG.
FIG. 2 shows a second embodiment of the air conditioner according to the present invention. In the first embodiment shown in FIG. 1, the refrigerant pipe and the intermediate heat between the second expansion device 18 and the third expansion device 28 are used. The refrigerant pipe connecting the exchanger 16 is provided with a fourth expansion device 46, and the second bypass pipe 30 bypasses the first expansion device 14, the intermediate heat exchanger 16, and the fourth expansion device 46. It is connected to the.
[0036]
Therefore, the refrigerant circuit including the first expansion device 14, the intermediate heat exchanger 16, the first bypass tube 26 having the on-off valve 24, the second expansion tube 30 having the third expansion device 28, and the fourth expansion device 46, The second medium circuit including the heat exchanger 16, the pump 34, and the reserve tank 36 is provided in the intermediate unit 4, and is detachably connected to the outdoor unit 2 and the indoor unit 6.
[0037]
The operation of the air conditioner having the above configuration according to the present invention will be described below. Here, similarly to the first embodiment, an airflow heat exchanger that exchanges heat with room air is used as the first use-side heat exchanger 12, and a floor heating mat with a built-in pipe is used as the second use-side heat exchanger 32. The case where water is used as the second medium will be described as an example.
[0038]
First, the operation during the heating operation will be described.
At the time of start-up, a circuit in which the airflow heat exchanger 12 and the intermediate heat exchanger 16 are connected in series with the on-off valve 24 and the third expansion device 28 closed and the first expansion device 14 and the fourth expansion device 46 fully opened. to start. The indoor unit 6 and the outdoor unit 2 perform a predetermined operation while communicating via the communication path 44. This control content is a control pattern when the intermediate unit 4 is not provided, and the airflow heat exchanger 12 warms room air to a desired temperature by a remote controller or the like.
[0039]
At this time, the contents of communication between the indoor unit 6 and the outdoor unit 2 can be referred to by the intermediate unit control unit 38. The intermediate unit 4 is provided inside the intermediate unit 4 such as the outlet pipe of the intermediate heat exchanger 16. Calculate the amount of heat required in the use side heat exchanger based on sensor information and change the signal content. That is, the amount of heat required in the intermediate unit 4 is added to the required amount of heat sent from the indoor unit 6, the communication content is corrected to a signal corresponding to the newly set required amount of heat, and the signal is sent to the outdoor unit 2. The outdoor unit 2 that has received the signal controls the valve opening degree of the second expansion device 18, the compressor frequency, and the like so as to provide the capability according to the request. The intermediate unit 4 operates the pump 34 as necessary, and the amount of heat obtained by the intermediate heat exchanger 16 is consumed by the heating heat using the floor heating mat.
[0040]
In the above description, the method of connecting and using the airflow heat exchanger 12 and the intermediate heat exchanger 16 in series at the time of starting the heating operation has been described. However, there is no problem if the airflow heat exchanger 12 and the intermediate heat exchanger 16 are started up in a circuit configured in parallel.
[0041]
When the room temperature rises and approaches the set temperature, the operation mode is switched to a floor heating-priority operation in which energy saving operation can be performed so that a feeling of heating can be obtained with a smaller amount of heat.
[0042]
During the floor heating priority operation, the on-off valve 24 is opened, the first expansion device 14 is fully closed, and the third expansion device 28 and the fourth expansion device 46 are appropriately opened, so that the refrigeration cycle is switched to the intermediate heat exchanger 16. And the airflow heat exchanger 12 are set to a cycle in which they are used completely in parallel. Also in this case, the outdoor unit 2 controls the valve opening degree, the compressor frequency, and the like of the second expansion device 18 in accordance with the corrected instruction signal given via the intermediate unit control unit 38 so as to provide the required performance. I do. The bed temperature is adjusted by controlling the amount of water circulation or controlling the opening of the third and fourth expansion devices 28 and 46. Further, when the floor temperature is desired to be raised, since the radiation loss in the airflow heat exchanger 12 can be suppressed by fully closing the third expansion device 28, all the heat quantity obtained in the outdoor unit 2 is reduced by the intermediate heat exchanger 16 It is given to the water circuit side via and used for floor heating. Further, if the fourth throttle device 46 is slightly throttled, the condensation temperature of the refrigerant can be increased. For this reason, it becomes possible to arbitrarily set the floor temperature under the control of the intermediate unit control unit 38.
Further, compared to the first embodiment, the fourth diaphragm device 46 enables finer adjustment of the performance.
[0043]
Next, the operation during the cooling operation will be described.
During the cooling operation, the four-way valve 10 is switched, and the first throttle device 14, the on-off valve 24, and the fourth throttle device 46 are all closed, and the third throttle device 28 is fully opened. The circuit configuration is the same as that of an air conditioner, and the cooling operation is performed using only the airflow similar to that of a general air conditioner.
[0044]
Next, the operation during hybrid operation will be described.
During the hybrid operation, the four-way valve 10 is set to the cooling position, the second throttle device 18 and the fourth throttle device 46 are both fully opened, the third throttle device 28 is fully closed, and the first throttle device 14 is appropriately set. Driving to narrow down. The control content of the outdoor unit 2 at this time corresponds to the reheat and dehumidification mode without the intermediate unit 4. That is, when performing the hybrid operation, the intermediate unit control unit 38 sends an instruction signal of the reheating and dehumidification operation to the outdoor unit control unit 42, and sends an instruction signal of the cooling operation to the indoor unit control unit 40, thereby controlling the intermediate unit control. The unit 38 uses the first throttle device 14 and the first throttle device 14 based on information obtained from the indoor unit control unit 40 and the outdoor unit control unit 42 and information of a sensor provided inside the intermediate unit 4 such as an outlet pipe of the intermediate heat exchanger 16. The fourth diaphragm device 46 is controlled. In this way, it becomes possible to perform the cooling operation by the airflow while suppressing the floor temperature from dropping too much.
[0045]
In the above embodiment, the case where no new sensor is added to the outdoor unit 2 has been described. However, if the information obtained from the communication path is insufficient, a discharge temperature sensor or the like is added to the intermediate unit control unit 38. You may connect.
[0046]
In the above embodiment, a subcritical refrigerant such as an HFC refrigerant (for example, R410A or R32) or an HCFC refrigerant (for example, R22) is used as a refrigerant, but a supercritical refrigerant such as CO ₂ can also be used. . That is, in the supercritical cycle, it is effective to increase the pressure in order to obtain a high second medium temperature, and an output at a different temperature can be realized within a limited range of the compressor operating frequency.
[0047]
Further, in the above embodiment, the second use side heat exchanger 32 is described as a floor heating mat, but the second use side heat exchanger 32 may be a hot water heating heat exchanger or a water heater, It is also possible to use brine (antifreeze) other than water as the second medium.
[0048]
【The invention's effect】
The present invention is configured as described above, and has the following effects.
ADVANTAGE OF THE INVENTION According to this invention, a 1st use side heat exchange is provided by providing a some throttle apparatus in the refrigerant piping which connects an outdoor unit, an indoor unit, and an intermediate unit mutually, and controlling the opening degree of a plurality of throttle apparatuses at the time of heating operation. Since the parallel connection and the series connection of the heat exchanger and the intermediate heat exchanger can be selected, if necessary, the first use side heat exchanger and the intermediate heat exchanger can be used in parallel or in series. An air conditioner with reduced heat dissipation loss during operation and improved economy and comfort can be provided at low cost.
[0049]
In addition, since the first use side heat exchanger is used for cooling and the intermediate heat exchanger is used for heating during the cooling operation, control of the room temperature by airflow and prevention of excessive cooling of the foot due to radiation are independently performed. It can be controlled with high accuracy. Therefore, for example, an air conditioner with higher comfort that reflects personal preferences without feeling uncomfortable during cooling can be realized at low cost.
[0050]
Furthermore, since the outdoor unit control unit that controls the outdoor unit and the indoor unit control unit that controls the indoor unit communicate via the intermediate unit control unit that controls the intermediate unit, for example, The intermediate unit including the intermediate heat exchanger is additionally installed between the indoor unit and the outdoor unit, so that it can be used without changing the control of the conventional unit, and the two use-side heat exchangers are individually controlled. An air conditioner with high comfort can be provided at low cost.
[Brief description of the drawings]
FIG. 1 is a cycle configuration diagram showing Embodiment 1 of an air conditioner according to the present invention.
FIG. 2 is a cycle configuration diagram showing Embodiment 2 of the air conditioner according to the present invention.
FIG. 3 is a cycle configuration diagram showing a conventional air conditioner.
[Explanation of symbols]
2 outdoor unit, 4 intermediate unit, 6 indoor unit, 8 compressor, 10 four-way valve, 12 first use side heat exchanger, 14 first throttle device,
16 intermediate heat exchanger, 18 second throttling device, 20 heat source side heat exchanger,
22 accumulator, 24 on-off valve, 26 first bypass pipe,
28 third throttle device, 30 second bypass pipe, 32 second use side heat exchanger, 34 pump, 36 reserve tank, 38 intermediate unit controller,
40 indoor unit control unit, 42 outdoor unit control unit, 44 communication path, 46 fourth throttle device.

Claims

An outdoor unit having a heat source side heat exchanger, an indoor unit having a first use side heat exchanger and performing air conditioning using a refrigerant, and an intermediate heat exchanger for exchanging heat between the refrigerant and a second medium An intermediate unit that heats the second medium with the refrigerant,
The outdoor unit, the indoor unit, and the intermediate unit are provided with a plurality of throttle devices in a refrigerant pipe that connects the intermediate units to each other. During the heating operation, the opening degrees of the plurality of throttle devices are controlled to control the first use-side heat exchanger and the heat exchanger. An air conditioner characterized in that parallel connection and series connection of an intermediate heat exchanger can be selected.

The plurality of expansion devices include first, second, and third expansion devices, and a compressor provided in the outdoor unit, the first usage-side heat exchanger, the first expansion device, the intermediate heat exchanger, The second expansion device and the heat source side heat exchanger are sequentially connected to constitute a cycle for circulating the refrigerant, and a pipe having the third expansion device bypasses the first expansion device and the intermediate heat exchanger. And a pipe connecting the compressor and the first use side heat exchanger with a pipe having an open / close valve, and a pipe connecting the first throttle device and the intermediate heat exchanger, The air conditioner according to claim 1, wherein a second use side heat exchanger is connected via an intermediate heat exchanger, and the second medium is circulated through the second use side heat exchanger. .

The plurality of expansion devices include first, second, third, and fourth expansion devices, and a compressor provided in the outdoor unit, the first use side heat exchanger, the first expansion device, the intermediate heat. An exchange, the fourth expansion device, the second expansion device, and the heat source side heat exchanger are sequentially connected to constitute a cycle for circulating the refrigerant, and a pipe having the third expansion device is connected to the first expansion device. A pipe connecting the intermediate heat exchanger and the fourth throttle device so as to bypass the fourth throttle device, and further connecting the compressor and the first use-side heat exchanger with a pipe having an on-off valve; and the first throttle device. And a pipe connecting the intermediate heat exchanger, a second use side heat exchanger is connected via the intermediate heat exchanger, and a second medium is circulated through the second use side heat exchanger. The air conditioner according to claim 1, wherein:

The air conditioner according to any one of claims 1 to 3, wherein a refrigerant is caused to flow in series between the intermediate heat exchanger and the first usage-side heat exchanger when heating is started.

The air conditioner according to any one of claims 1 to 4, wherein a refrigerant is caused to flow in parallel to the intermediate heat exchanger and the first usage-side heat exchanger during a heating operation.

The air according to any one of claims 1 to 5, wherein during the cooling operation, the first use side heat exchanger is used for cooling, and the intermediate heat exchanger is used for heating. Harmony machine.

The outdoor unit control unit that controls the outdoor unit and the indoor unit control unit that controls the indoor unit communicate via an intermediate unit control unit that controls the intermediate unit. The air conditioner according to any one of claims 1 to 6.