JP4258117B2

JP4258117B2 - Air conditioner

Info

Publication number: JP4258117B2
Application number: JP2000299756A
Authority: JP
Inventors: 泰隆村上; 義浩田辺; 辰夫関; 利彰吉川; 史武畝崎
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2000-09-29
Filing date: 2000-09-29
Publication date: 2009-04-30
Anticipated expiration: 2020-09-29
Also published as: JP2002107001A

Description

【０００１】
【発明の属する技術分野】
本発明は、空気調和機に関わり、特に、室内温度と湿度を快適にする空気調和機に関する。
【０００２】
【従来の技術】
従来の空気調和機においては、図１１に示すように、圧縮機１、四方切換弁、室外熱交換器２、第１の絞り調整機構３、第１の室内熱交換器４、電磁弁を有する主回路、第２の室内熱交換器６が順次配管で接続され、かつ、前記電磁弁を有する主回路と並列に第２の絞り調整機５が配管で接続されて冷凍サイクルが構成されおり、この冷凍サイクルの冷房運転時には、冷媒が第２の絞り調整機構５を介さずに、主回路を流れるように電磁弁を開き、第１の室内熱交換器４と第２の室内熱交換器６を蒸発器として機能させて冷房を行い。
【０００３】
また、室内相対湿度を主に下げる除湿運転時には、第１の絞り調整機構を全開にして主回路の電磁弁を閉じて、第１の室内熱交換器４が凝縮器（加熱器）として機能し、第２の室内熱交換器６が蒸発器として機能するようにして、冷媒を第２の絞り調整機構５で絞り、一方の第１の室内熱交換器４で過熱しながら、他方の第２の室内熱交換器６で通過空気を冷却し、その後、この冷却された空気と加熱された空気を混合して室温を余り下げずに、顕熱を主体とした除湿運転を行うようにするものであった。
【０００４】
しかし、このような第１の絞り調整機構を全開にして第２の絞り調整機構５で冷媒を絞って除湿運転をするようにしたものにおいては、室内温度（顕熱負荷）に応じて圧縮機の周波数を上げて行くと、冷媒流速の関係からある周波数以上で第２の絞り調整機構５から冷媒音が発生するため、圧縮機の周波数を冷媒音が発生しない所定周波数まで上げた後、室外ファン８の回転数を上げて、室内の高い相対湿度に対応していた。
即ち、室外ファン８の回転数を上げて高圧を上げ、圧縮比が高い状態で運転しているため、圧縮機の吐出温度が上がったり、消費電力を多く消費するものであった。
【０００５】
また、このような圧縮機１の周波数を一定に維持しながら、室外ファン８の回転数を上げて除湿運転を行うものは、図１２に示すように、圧縮機１の周波数と室外ファン８の回転数が決まれば、顕熱能力と潜熱能力とがそれぞれ決まり、この決まった顕熱能力と潜熱能力の夫々に対応した室内温度及び湿度となるように制御する。
【０００６】
従って、室内湿度をある目標設定湿度にしようとして潜熱能力を決めると、この決まった潜熱能力と対応した顕熱能力で室内温度を制御し、逆に、室内温度をある目標設定温度にしようとして顕熱能力を決めると、この決まった顕熱能力に対応した潜熱能力で室内湿度を制御するようになるので、室内の温度と湿度を目標温・湿度にすることが難しかった。
【０００７】
言い換えれば、その時の空調装置の顕熱能力又は潜熱能力と、室内潜熱負荷又は室内顕熱負荷が等しい時には、室内温度及び湿度を目標設定温度及び湿度にできるものの、等しくない時には、室内温度及び湿度のいずれか一方が目標値になると、他方の値は目標値にならず、単に、その他方の能力と釣合った値で室内の状態を維持するようなものとなる。
【０００８】
従って、このようなものは、室内温度が適正目標設定温度にあるにも関わらず、室内湿度が高い時には、室内湿度を低下させるために、室外ファン８の回転数を低下させ、第１室内熱交換器の温度を上げて加熱量をアップさせるので、室内温度が上がるため、圧縮機の回転数を上げなければならず、この回転数アップ分だけ更に加熱量が上がるので、その結果、このアップ加熱量の分だけ、室外ファン８の回転数を再度増加させる必要があり、このようなものは、圧縮機の回転数及び室外ファン８の回転数を予測して制御しなければならず、難しい制御が強いられるだけでなく、正確性も低く、しかも、潜熱能力を考慮していないため、潜熱負荷に対する潜熱能力のバランスが取れず、また、圧縮機の回転数をアップさせた分、消費電力も大きいものであった。
【０００９】
また、圧縮機の周波数を固定せず、第２の絞り調整機構５の冷媒音を室内ファン７の回転数を上げて、その送風音によってマスキングするようにしたものにおいては、即ち、圧縮機の周波数及び室内ファン７の風速を増大させるものにおいては、図１２に示すように、蒸発能力及び蒸発温度が上昇して顕熱比が大きくなるので、室内温度低下に寄与する顕熱能力は増加するものの、室内の絶対湿度低下に寄与する潜熱能力はほとんど増加しなくなり、結果として除湿性能が低下した状態で運転されるため、室内湿度を目標設定湿度にすることはできなかった。
【００１０】
また、これらの従来の空気調和機における再熱除湿運転においては、経済的理由から第２絞り調整機構５を固定開度にしているために、第２の室内熱交換器（蒸発器）の出口冷媒温度と圧縮機の吸入冷媒温度との温度差である所謂吸入スーパーヒート（過熱度）は圧縮機の周波数が変化すると、変化するものであった。
【００１１】
従って、このようなものは、例えば、第２の室内熱交換器（蒸発器）６の熱交換能力を確保しながら圧縮機へ冷媒液が戻らないように、第２の絞り調整機構５の絞り量、即ち、過熱度を低い周波数帯に合わせて設定しても、その後、室内負荷の関係から圧縮機の周波数を上げ、冷媒循環量を多くした時は絞り過ぎとなって、第２の室内熱交換器の出口冷媒温が過熱気味となり、圧縮機の各部温度が上昇し、圧縮機を破損させたりしていた。
【００１２】
また逆に、第２の絞り調整機構５の絞り量（過熱度）を高い周波数帯に設定した後、室内負荷の関係から圧縮機の周波数を低下させ、冷媒循環量を少なくした時は、開き気味となり、液冷媒が圧縮機１に戻るようになるため、圧縮機を破損させたり、除湿性能の低下をまねいていた。
【００１３】
また、これらの再熱除湿運転における第２の絞り調整機構５の開口面積は、一般的に、第１の絞り調整機構３の開口面積よりも小さいため、不純物等が詰まりやすく、現に不純物等が詰まり、冷媒循環が低下して圧縮機の吸入冷媒過熱度が大きくなっても再熱除湿運転を継続するため、この詰まり運転に起因して発生する圧縮機のト各種ラブルも発生していた。
【００１４】
また、その他の従来例としては、特開平６−１３７７１１に示されるようなものがある。しかし、このようなものは冷房運転において、冷房運転中に室内温度を下げるという目的から圧縮機の能力を室内温度（顕熱負荷）に応じて制御し、除湿運転中には室内湿度に応じて圧縮機の能力を制御しているため、冷房運転時と除湿運転時における圧縮機能力の制御のやり方が相違し、複雑な制御をするものであった。
【００１５】
【発明が解決しようとする課題】
従来の空気調和機は、以上説明したように構成されているので、室内温度と相対湿度を目標温・湿度にすることが難しかった。
【００１６】
また、除湿運転時に室内のファン風速を上げて、第２の絞り調整機構５の冷媒音をマスキングするようなものにおいては、風速の増大によって顕熱比が大きくなり、室温は低下するものの、除湿性能が低下してしまうという問題があった。
【００１７】
また、不純物等が第２の絞り調整機構に詰まり、過熱度が大きくなっても、除湿冷却運転を継続するため、圧縮機のトラブルが発生するという問題点があった。
【００１８】
この発明は係る問題を解決するためになされたもので、冷房、暖房時の種々の負荷条件が変化しても、室内温・湿度をスピーディに目標温・湿度して、室内を快適する信頼性の高い空気調和機を得ることを目的とする。
【００１９】
また、この発明は、室内の温度と目標温度と温度差に基づいて自動的に冷房運転をしたり、再熱除湿運転をしたりして室内を快適にする使い勝手の良い空気調和機を得ることを目的とする。
【００２０】
また、この発明は、各機器のトラブルを未然に防止して室内を快適する信頼性の高い空気調和機を得ることを目的とする。
【００２１】
【課題を解決するための手段】
この発明の空気調和機は、圧縮機、室外熱交換器、第１の絞り調整機構、第１の室内熱交換器、第２の絞り調整機構、第２の室内熱交換器が順次配管で接続され、第１の室内熱交換器と第２の室内熱交換器とを共に蒸発器として機能させる冷房運転と、第１の室内熱交換器を凝縮器として、第２の室内熱交換器を蒸発器として機能させ室内相対湿度を下げる再熱除湿運転と、を行う空気調和機であって、制御手段が、冷房運転から再熱除湿運転になった時、室内相対湿度が目標相対湿度よりも高い場合には、圧縮機の回転数を冷房運転終了時の圧縮機の回転数より上昇させ、室内相対湿度が目標相対湿度よりも低い場合には、圧縮機の回転数を冷房運転終了時の圧縮機の回転数より減少させるように制御するとともに、第１の絞り調整機構の開度を制御して、第１の室内熱交換器の加熱能力と第２の室内熱交換器の冷却能力との割合が室内の顕熱負荷と潜熱負荷との割合に合うように再熱除湿運転を行うものである。
【００２８】
また、再熱除湿運転を行っている時に、外気温度が変化した場合には、制御手段が、その変化に対応して室外熱交換器のファンの回転数を制御して第１の室内熱交換器の加熱能力を変化させ、第１の室内熱交換器の加熱能力と第２の室内熱交換器の冷却能力との割合が室内の顕熱負荷と潜熱負荷との割合に合うようにするものである。
【００２９】
また、再熱除湿運転を行っている時に、室内温度が目標設定温度より高くなって、室内相対湿度が目標相対湿度よりも高い場合には、制御手段が、第１の絞り調整機構の開度を絞って、第１の室内熱交換器の凝縮温度を室内温度以下として第１の室内熱交換器の加熱能力をゼロとするものである。
【００３４】
【発明の実施の形態】
実施の形態１．
図１は、この発明の実施の形態１における空気調和機の概略構成図であり、この図において、１は圧縮機、２は室外熱交換器、３は電気式膨張弁等の第１の絞り調整機構、４は第１の室内熱交換器、５は固定開度のオリフィスやキャピラリや電気式膨張弁等からなる第２の絞り調整機構、６は第２の室内熱交換器、７は室内送風機、８は室外送風機である。
なお、この図の第１の室内熱交換器と第２の室内熱交換器との間に設けられた第２の絞り調整機構５は、そこを通過する冷媒音を消音化する多孔質体を備えており、かつ、この第２の絞り調整機構５と並列に、冷房運転時に開となり、除湿運転時に閉となる電磁弁６を備えた主回路を有している。
【００３５】
また、この図の１１は室内に設けられ、室内の相対湿度を検出する室内湿度検出手段、１２は室内に設けられ、室内の温度を検出する室温センサー、１３は第１の室内熱交換器４に設けられ、該熱交換器の入口温度を検出する第１の入口温度センサー、１４は第２の室内熱交換器４に設けられ、該熱交換器の入口温度を検出する第２の入口温度センサー、１５は外気温センサー、１６は室内ユニットの外表面に設けられ、リモコン１７からの信号を受信するリモコン受光部（図示せず）、１７は室内の目標温・湿度や、冷・暖房、再熱除湿運転等の運転モードを指示するリモコンである。
【００３６】
また、この図の９は室内ユニットに設けられ、上記各センサからの信号に基づいて室内ユニット内の各機器（例えば、室内ファン７や、第２の絞り調整機構５等）を制御したり、室外マイコン１０と通信する室内マイコンであり、１０は室外ユニットに設けられ、室外マイコン１０と通信したり、上記各センサから信号に基づいて室外ユニット内の各機器（例えば、圧縮機１や室外ファン８の回転数、第１の絞り調整機構３の開度等）を制御する室外マイコンであり、制御手段（図示せず）は、これらの室外マイコン１０や室内マイコン９等から構成される。
【００３７】
次に、このように構成された動作について説明する。
まず、室内空気の除湿を下げる再熱除湿運転においては、制御手段が主回路の電磁弁を閉じて、冷媒が第２の絞り調整機構５を介して第１の室内熱交換器から第２の室内熱交換器へ流れるようにすると共に、第１の室内熱交換器が凝縮器として機能するように、第１の絞り調整機構３の開度を調整し、かつ、蒸発器として機能する第２の室内熱交換器６の（蒸発）温度を室内空気の露点温度以下にし、その室内通過空気を冷却しながら冷却除湿する。
【００３８】
なお、この時、冷却除湿を多くするために蒸発温度を余り下げると、室内空気の温度も低下してしまい、室温が目標設定温度以下になる恐れがあるので、室温を余り下げずに除湿するために、凝縮器として機能する第１の室内熱交換器４で通過室内空気の一部を加熱し、その通過室内空気の残りを蒸発器として機能する第２の室内熱交換器６を通過させて冷却し、その後、これらの通過室内空気を混合し、適度な温・湿度にした後、吹出口から室内へ吹出す。
【００３９】
また、この除湿冷却運転においては、前述したように室内熱交換器が、第１と第２の室内熱交換器４、６に区分され、特に、第２の室内熱交換器のみが蒸発器となり、蒸発器の冷却能力が約半分程度となり、凝縮器の放熱容量が増えるため、このことを考慮した制御を行うこととなる。
【００４０】
従って、例えば、インバータ（圧縮機の回転数）制御で室内負荷と装置能力をバランスさせるようにしたものにおいては、室内温度が目標設定温度になった冷房運転終了時の圧縮機や室外ファンの回転数で除湿冷却運転へ切換えると、前述したように、第１の室内熱交換器４が凝縮器として機能するため、冷凍サイクルの凝縮器の放熱量（凝縮能力）が増大すると共に、第１の室内熱交換器４で加熱され、かつ、蒸発器の熱交換能力が減少し、室内温度が上昇するので、これを防止するため、目標設定温度に達した冷房運転時の圧縮機の回転数よりも更に回転数を上げ、この上げた能力分で室内を目標設定温度に維持しながら目標設定湿度になるように必要加熱量を付与して室内空気を快適な目標温・湿度にすることとなる。
【００４１】
また、室内負荷よりも装置能力が大きく、室内目標設定温度の所定温度範囲内で制御する所謂サーモ運転制御のものにおいては、放熱量を確保するために室外ファンの回転数を凝縮器の容量変化（外気温度変化）に応じて下げる必要があるものの、装置能力が室内負荷よりも大きいため、圧縮機の回転数は冷房運転終了時の回転数で運転しても室温が上昇しないから、回転数を上げなくても良いこととなる。
【００４２】
しかし、いずれにしても、室内空気の温・湿度を快適な目標温・湿度にするためには、加熱手段として機能する第１の室内熱交換器４の凝縮温度（加熱温度）を第１の絞り調整機構３の開度によって調整すると共に、この調整によって固定開度である第２の絞り調整機構５を介した蒸発器として機能する第２の室内熱交換器６の温度（冷却温度）と冷却能力とも調整して、加熱量と冷却量とを調整しながら室内空気を快適な目標温・湿度にすることになる。
【００４３】
従って、この時、例えば、図５に示すように、第１の絞り調整機構３の開度を絞り、その絞った時の冷凍サイクルをAとし、この冷凍サイクルAにおける第１の絞り調整機構３を更に絞った時の冷凍サイクルをＢとすると、この絞り量の多い冷凍サイクルＢの方が絞り量の少ない冷凍サイクルＡよりも第１の室内熱交換器４へ供給される冷媒が少なくなると共に、その時の加熱温度も低下して室温に近くなるので、熱交換容量が大幅に小さくなって加熱力が大幅に減少するため、加熱能力に対する冷却能力の割合が増大する。また、この逆の動作をさせると、逆に、加熱能力に対する冷却能力の割合が減少するので、第１の絞り調整機構３の開度を大きくしたり、小さくしたりして図３に示すように、加熱能力（顕熱）と冷却能力（顕熱＋潜熱）の割合、即ち、顕熱能力と潜熱能力との割合を調整して室内の顕熱負荷と潜熱負荷に合うようにし、室内空気を快適な目標温・湿度にする。
【００４４】
言い換えれば、第１の絞り調整機構３を絞って第１の室内熱交換器４の凝縮温度を室温以下にして加熱量をゼロにしたり、或いは、室温以上にして加熱したりして室内空気を快適な目標温・湿度にする。
なお、室温以下にして加熱量をゼロにすると、図３に示すように、室内温度と湿度と割合である潜熱と顕熱との勾配は蒸発温度のみの関数となるので、第１の絞り調整機構３の開度を調整し、蒸発温度を調整することによって、余分なエネルギーで加熱することなく、空調機の潜熱能力と顕熱能力との割合を制御できるようになる。
【００４５】
次に、以上のことを踏まえ、例えば、室温が目標設定温度以上（例えば、目標設定温度２５℃に対して２８℃）で相対湿度が高い（８０％以上）時には、図２に示すように、第１の室内熱交換器４の凝縮温度が室温以下になるように、即ち、加熱量がほぼゼロで、冷却を主体にするように、第１の絞り調整機構３の開度を絞り、第２の室内熱交換器６の蒸発温度をＡからＢへ変化させ、図５に示すように、室内温・湿度に対する目標温・湿度の勾配（SHF）をＡからＢに変化させて、目標温・湿度がSHF（顕熱比線）上に乗るようにして、装置能力と室内負荷とを合わせ、室内を快適な目標温・湿度にする。
【００４６】
なお、この加熱量をゼロにしたものにおいては、第１の絞り調整機構３を絞るため、蒸発温度が低下し、室温との温度差が大きくなり、熱交換器容量は増加するものの、冷媒循環量が大幅に減少し、冷却能力が減少するので、室温が余り低下せずに、室内絶対湿度が主に下がるようになるため、室内の相対湿度が低下することとなる。
【００４７】
また、この制御中に、外気温が高くなったり、室内の発熱物体（室内人員数等）によって室温が上昇したりした時は、室外ファン回転数を上げて高圧（加熱状態）が変化しないようにしたり、圧縮機の回転数を高くして負荷に対応したり、或いは、第１の絞り調整機構３の開度を調整したりして目標温・湿度がSHF（顕熱比線）上に乗るように制御する。
【００４８】
また、室温がほぼ目標設定温度（２５℃）で相対湿度が高い（８０％以上）時には、第１の室内熱交換器４の温度が室温以上となるように、第１の絞り調整機構３の開度を制御し、加熱量を調整して室温を維持しながら、室内湿度が目標設定湿度になるようにする。
【００４９】
即ち、室内温度がほぼ目標設定温度で、湿度が高い時は、図５に示すように、主に加熱力によって湿度を下げるため、第１の室内熱交換器４の凝縮温度を室温よりもやや高くなるように第１の絞り調整機構３の開度を調整して、室内湿度を下げるために、第１の室内熱交換器４でやや加熱しながら、この加熱力によって室温が上昇しないように、第２室内熱交換器６の冷却能力の顕熱能力分で加熱力をキヤンセルするようにして、室内温度の低下を防止しながら相対湿度を下げて、室内を快適な目標温・湿度にする。
【００５０】
なお、第２室内熱交換器６の冷却能力の顕熱冷却能力で加熱力をキヤンセルするためには、第１と第２の室内熱交換器の熱交換容量（能力）がほぼ同じであれば、室温と第１の室内熱交換器４の温度との温度差が、室温と第２の室内熱交換器６の温度との温度差とほぼ同じになるようにすれば良い。即ち、第１と第２の室内熱交換器の容量比に基づいて温度差比率を考えて処理すれば良い。
【００５１】
また、室内温度が目標設定温度（２５度）よりも低く、例えば、２３℃の時、言い換えれば、余り蒸し暑さを感じない室内絶対湿度が低い時は、図２に示すように、第１の絞り調整機構３の開度をほぼ全開にして、室温低下に繋がる第２の室内熱交換器６の温度低下を防止しながら、空気側の変化を図３に示すように、加熱量を大きくし、この加熱力（凝縮温度＝外気温度＋約１５℃）によって室温を目標設定温度にすると共に、室内の相対湿度を下げて、室内を快適な目標温・湿度にする。
即ち、室内の温度及び絶対湿度が低く、余り蒸し暑さを感じない時は、外温度も低く、冷凍サイクルのCOPも良い（冷却能力に対する消費力が少ない）ので、加熱温度を大幅に上げ、加熱力を主体とした相対湿度の低下を図る。
また、室内温度が目標設定温度よりも遥かに低く、室内湿度を下げたい時には、暖房運転に切換えるようにしても良い。
【００５２】
なお、以上のような制御をする場合は、当然、図４に示すように、空気線図上で、室内温・湿度と目標温・湿度とを結んで飽和温度線（相対湿度１００％）線とぶつかった点の乾球温度が、例えば５℃以下になった時は、空調機の冷却能力が低下するだけでなく、外気温度の変動によって霜も付く恐れもあるので、この時点から加熱するようにする。
即ち、例えば、５℃以下の０℃になった時は、５℃の飽和湿度点と目標温・湿度とを結ぶ線が室内温・湿度の顕熱線とぶつかる点（第１室内熱交換器の吹出空気温度）を求め、この点と室内温・湿度とのエンタルピ差から必要加熱力を求め、この必要加熱力が得られように第１室内熱交換器の温度が設定されるように、第１の絞り機構の開度が制御されることとなる。
【００５３】
また、一般的に、冷房運転時の冷凍サイクの冷房能力（冷却能力）に対する放熱能力（凝縮能力）の比は、ＣＴ＝４５℃、ＥＴ＝１０℃で、ほぼ１．３前後であり、また除湿運転時には、第１の室内熱交換器４が凝縮器となり、放熱容量が更に増えるので、凝縮温度が下がり、それに伴って蒸発温度も下がるため、第１の絞り調整機構３の開度を全開するだけでは対応できないことも起こるので、この場合は、後述すように、室外ファンの回転数を下げたり、或いは、圧縮機１の回転数を上げたりして対応する。
【００５４】
また更に、前述したように、冷却能力に対する凝縮能力の比（１．３）に応じて凝縮器と蒸発器との面積比を決めるのが一般的であるから、凝縮器として機能する第１の室内熱交換器４に対する第２の室内熱交換器６の面積比を１以上となるようにすると、室外ファンの回転数を下げて凝縮温度を上げたのとほぼ同じこととなり、外気温度が低下しても対応できるようになるため、使い勝手の良い空気調和機が得られる。
【００５５】
また、前述の絞り量を多くしたものにおいては、冷媒が室外熱交換器２内に溜まるため、室外熱交換器側の圧力（温度）が若干上がり、第１の室内熱交換器の温度も上がるので、これらのことを考慮しながら制御することは言うまでもない。
【００５６】
また、再熱除湿運転以外の冷房運転又は暖房運転においては、冷媒が第２の絞り調整機構を流れずに主回路を流れるようにし、第１、第２の室内熱交換器４，６共に、蒸発器又は凝縮器として機能させて運転を行なう。
【００５７】
以上説明したように、室内空気を再熱除湿する空気調和機において、制御手段が、前記第１の室内熱交換器の温度に基づいて前記第１の絞り調整機構の開度を制御し、該第１の室内熱交換器を通過する前記室内空気への加熱量を調整しながら空調機の潜熱能力と顕熱能力との割合が室内の顕熱負荷と潜熱負荷の割合にほぼ合うようにしたので、室内負荷が変化しても、この変化に追従して室内を目標温・湿度状態にするようになるため、室内を快適な温・湿度にする信頼性の高い空気調和機が得られる。
【００５８】
また、前記制御手段が、前記室内空気の温度が目標設定温度以下の時に、前記第１の室内熱交換器の温度が前記室内空気の温度以上となるように前記第１の絞り調整機構の開度を制御するので、第１の室内熱交換器を通過する空気を過熱にしながら室内温度を確実に目標温度にして室内を快適な温・湿度にする信頼性の高い空気調和機が得られる。
【００５９】
また、前記制御手段が、前記室内空気の温度が目標設定温度以上の時に、前記第１の室内熱交換器の温度が前記室内空気の温度以下となるように前記第１の絞り調整機構の開度を制御するので、第１の室内熱交換器を通過する空気を過熱しないないで無駄なエネルギーを供給することなく、室内を快適な温・湿度にする信頼性の高い空気調和機が得られる。
【００６０】
実施の形態２．
図１は、この発明の実施の形態１における空気調和機の概略構成図であり、この図において、１は圧縮機、２は室外熱交換器、３は電気式膨張弁等の第１の絞り調整機構、４は第１の室内熱交換器、５は固定開度のオリフィスやキャピラリや電気式膨張弁等からなる第２の絞り調整機構、６は第２の室内熱交換器、７は室内送風機、８は室外送風機である。
なお、この図の第１の室内熱交換器と第２の室内熱交換器との間に設けられた第２の絞り調整機構５は、そこを通過する冷媒音を消音化する多孔質体を備えており、かつ、この第２の絞り調整機構５と並列に、冷房運転時に開となり、除湿運転時に閉となる電磁弁６を備えた主回路を有している。
【００６１】
また、この図の１１は室内に設けられ、室内の相対湿度を検出する室内湿度検出手段、１２は室内に設けられ、室内の温度を検出する室温センサー、１３は第１の室内熱交換器４に設けられ、該熱交換器の入口温度を検出する第１の入口温度センサー、１４は第２の室内熱交換器４に設けられ、該熱交換器の入口温度を検出する第２の入口温度センサー、１５は外気温センサー、１６は室内ユニットの外表面に設けられ、リモコン１７からの信号を受信するリモコン受光部（図示せず）、１７は室内の目標温・湿度や、冷・暖房、再熱除湿運転等の運転モードを指示するリモコンである。
【００６２】
また、この図の９は室内ユニットに設けられ、上記各センサからの信号に基づいて室内ユニット内の各機器（例えば、室内ファン７や、第２の絞り調整機構５等）を制御したり、室外マイコン１０と通信する室内マイコンであり、１０は室外ユニットに設けられ、室外マイコン１０と通信したり、上記各センサから信号に基づいて室外ユニット内の各機器（例えば、圧縮機１や室外ファン８の回転数、第１の絞り調整機構３の開度等）を制御する室外マイコンであり、制御手段（図示せず）は、これらの室外マイコン１０や室内マイコン９等から構成される。
【００６３】
次に、このように構成された動作について説明する
まず、冷房運転時には、制御手段は第２の絞り調整機構５を閉じて主回路の電磁弁を開くので、第１及び第２の室内熱交換器４、６が蒸発器として機能し、第１の絞り調整機構３のみで冷媒量をコントロールしながら室内を冷房する。
なお、この時、制御手段は室内温度と目標設定温度との温度差に基づいて圧縮機の回転数を制御し、室内温度が速く目標設定温度となるようにする。
【００６４】
次に、制御手段は、室内温度が目標設定温度になると、主回路の電磁弁を閉じて、冷媒が第２の絞り調整機構５を介して第１の室内熱交換器から第２の室内熱交換器へ流れるようにすると共に、第１の室内熱交換器が凝縮器として機能するように、第１の絞り調整機構３の開度を調整し、かつ、この第１の絞り調整機構３の開度を介して蒸発器として機能する第２の室内熱交換器６の（蒸発）温度を室内空気の露点温度以下になるように制御して、第２の室内熱交換器６を通過する空気を冷却すると共に、第１の室内熱交換器４を通過した室内空気を加熱し、これらの室内空気を混合して適度な温・湿度にした後、吹出口から室内へ吹出して再熱除湿運転をする。
【００６５】
なお、この時、室内温度が目標設定温度になっていない状態、即ち、図１０の顕熱能力（冷却能力）が不足しているA状態で再熱除湿運転へ切換えると、この再熱除湿運転では加熱力が加わるため、目標室温にするのに時間がかかるので、室温がほぼ目標設定温度になってから、冷房運転から再熱除湿運転へ切換える。言い換えれば、図１０の室内温度と目標設定温度とがほぼ等しくなったＢ又はＣ状態の時に、冷房運転から再熱除湿運転へ切換える。
【００６６】
また、室内温度が目標設定温度になっていても、この目標設定温度における圧縮機の回転数が所定回転数以上の時は、この再熱除湿運転では加熱力が加わり、前述したように圧縮機の回転数を上げる必要があるため、室内負荷に対して装置能力が足りなくなったり、或いは、外気温度と室内温度との温度差（室内顕熱負荷）が大きいので、室内外差（室内顕熱負荷）が小さいものに較べ、絶対湿度を取れば室内の相対湿度は低下すると判断し、室内空気の相対湿度を下げる必要がないと制御手段が判断して冷房運転から再熱除湿運転へ切換え無い。
【００６７】
次に、この再熱除湿運転においては、前述したように室内熱交換器が、第１と第２の室内熱交換器４、６に区分され、特に、第２の室内熱交換器のみが蒸発器となり、蒸発器の冷却能力が約半分程度となり、凝縮器の放熱容量が増えるため、このことを考慮した制御をする。
【００６８】
従って、例えば、インバータ（圧縮機の回転数）制御で室内負荷と装置能力をバランスさせる本発明のようなものにおいては、室内温度が目標設定温度になった冷房運転終了時の圧縮機や室外ファンの回転数で除湿冷却運転へ切換えると、前述したように、第１の室内熱交換器４が凝縮器として機能して通過空気を温めると共に、凝縮器容量（放熱容量）が増大し、かつ、蒸発器容量が減少するため、室内温度が上昇するので、これを防止するため、目標設定温度に達した冷房運転時の圧縮機の回転数よりも更に回転数を上げ、この上げた能力分で室内を目標設定温度に維持しながら目標設定湿度になるように必要加熱量を付与して室内空気を快適な目標温・湿度になるようにする。
【００６９】
即ち、例えば、室内相対湿度が目標相対湿度よりも高い時は、第１の室内熱交換器が蒸発器から凝縮器に変わり、室内空気が加熱されると共に、更に熱交換器の冷却能力が低下することを考慮して圧縮機の回転数をアップし、室内相対湿度が目標相対湿度より低い時は、圧縮機の回転数をダウンし、同じ時は、圧縮機の回転数を維持するように制御する。
【００７０】
言い換えれば、本発明のように第２室内熱交換器６の出口冷媒温度に基づいて第１の絞り調整機構の開度を変えるものにおいては、圧縮機の回転数を変化させ、冷凍サイクル内の冷媒循環量を変えることにより、第２室内熱交換器６の出口冷媒温度が変化し、冷凍サイクルの蒸発能力と凝縮能力の能力比も変わり、第１の室内熱交換器の加熱力（温度）も大幅に変わるから、このことを考慮して、まず、前述した冷却能力低下分、即ち室内目標設定温度を維持するための圧縮機の回転数を求め、次に、室内空気の湿度をコントロールする加熱力を引き出すための冷却能力アップ分、言い換えれば、この冷却能力アップ分と対応した加熱量を、図３に示すように、空気側の要求加熱量から求め、この要求加熱量に対応した圧縮機の回転数を求めた後、これらの求めた回転数を目標設定温度における圧縮機の回転数に加算して制御し、図６、９に示すように、第１の絞り調整機構の開度を介して室内負荷に合わせる。
【００７１】
なお、この制御において、外気温度（凝縮温度）が低かったり、高かったりして加熱力が不足したり、多すぎたりした時は、外気温度等に応じて室外ファンの回転数を変えて対応する。
【００７２】
以上説明したように、室内温度が目標温度になった時に、冷房運転から再熱除湿運転に切換わるので、室内温度を目標温度に維持して自動的に室内湿度をスピーディに目標湿度にするようになるため、室内をスピーディ快適な温・湿度にする使い勝手の良い空気調和機が得られる。
【００７３】
実施の形態３．
この実施の形態３においては、実施の形態１、２の構成と動作において、再熱除湿運転を行なっている時に、外気温度又は室内負荷が変化し、その結果、室外熱交換器２の温度又は室内顕熱負荷と潜熱負荷との割合が変った時、室外ファン８の回転数を制御し、第１の室内熱交換器の温度（加熱力）を維持したり、加熱力を変化させたりするものである。
即ち、外気温度が低くなったり、高くなったり、或いは、室内顕熱負荷に対する潜熱負荷の割合が大きくなったり、小さくなったりした時、図７、８に示すように、圧縮機１又は室外ファン８の回転数（風速）を下げたり、上げたりして、加熱手段としての第１の室内熱交換器の温度（加熱力）を変化させ、室内顕熱負荷と潜熱負荷との割合が空気調和機の顕熱能力と潜熱能力との割合とほぼ合うようにしたものである。
【００７４】
なお、このような構成において、室外ファン速を低下させると、図７に示すように、室外熱交換器２の放熱容量が低下し、凝縮温度が上昇し、この凝縮温度の上昇に伴って加熱手段である第１の室内熱交換器４の凝縮温度（加熱温度）も上昇し、室内熱交換器４の放熱容量（加熱量）が増大すると共に、放熱エンタルピ差も凝縮量Bから凝縮量Aへと増大する。
また逆に、室外ファン速を上げると、室外側の凝縮温度が下がり、凝縮器としての第１の室内熱交換器４の凝縮温度（加熱温度）も下がるため、室内温度との温度差が小さくなり、室内熱交換器４の放熱容量（加熱量）が減少すると共に、放熱エンタルピ差も減少する。
【００７５】
従って、室内顕熱負荷と密接に関係する外気温度が低下し、加熱力が下がった時は、室外ファン速を下げて、加熱力を上げ、バランスさせたり、また逆に、外気温度が上昇した時は、室外ファン速を上げて、加熱力を下げ、バランスさせるようにしたり、或いは、室内顕熱負荷又は潜熱負荷が変化し、顕熱負荷と潜熱負荷との割合が変化した時は、図７に示すように、室外ファン８の回転数を制御して、空気調和機の顕熱能力と潜熱能力との割合を室内顕熱負荷と潜熱負荷との割合に合わせ、室内負荷の変化に対応できるようにする。
言い換えれば、室内目標温・湿度に対する室内温・湿度の勾配である顕熱比線（ＳＨＦ）が変化した時、この変化した顕熱比線に合うように室外ファン８の回転数を制御する。
【００７６】
以上説明したように、室内負荷や外気温度の変化に応じて室内顕熱負荷と潜熱負荷との割合が空気調和機の顕熱能力と潜熱能力との割合とほぼ合うように室外ファン８を制御したので、室内負荷や外気温度が変化しても対応できるようになるため、更に信頼性の高い空気調和機が得られる。
【００７７】
実施の形態４．
この実施の形態４においては、実施の形態２の構成と動作において、冷房運転から再熱除湿運転へ切換える時、圧縮機を所定時間停止した後、切換えるものである。
【００７８】
即ち、この実施の形態４においては、冷媒が流れている状態で、再熱除湿運転から冷房運転に切換えたり、逆に冷房運転から再熱除湿運転に切換えて主回路の開閉弁（電磁弁）を開いたり、閉じたりしようとしても、開閉弁前後の冷媒差圧の関係、或いは冷媒流の運動エネルギーの関係から開閉弁を開いたり、閉じたりすることができなくなるため、制御手段がリモコン等からの運転モードの切換信号を受信すると、圧縮機を所定時間停止し、冷媒の差圧や運動エネルギーをなくしてから、再熱除湿運転から冷房運転へ、或いは冷房運転から再熱除湿運転へ運転モードを切換える。
【００７９】
なお、このようにすると、第２の絞り調整機構の開閉動作がスムースになり、確実に運転モードが切換えられるようになるため、冷房運転と再熱除湿運転を確実に行う信頼性の高い空気調和機が得られる。
【００８０】
実施の形態５．
この実施の形態５においては、実施の形態１から４の構成と動作において、再熱運転時における圧縮機の周波数を室内湿度と目標設定湿度との湿度差に基づいて制御するものにおいて、室温が目標設定温度になっているにも関わらず、室内湿度が目標設定湿度よりも高い時に、温度差を補正して圧縮機の周波数を制御するものである。
【００８１】
即ち、この実施の形態５においては、図８に示すように、再熱運転時における圧縮機の周波数を室温と設定温度との温度差（顕熱負荷）に基づいて制御するものにおいて、室温と設定温度との温度差が小さくなると、例え、室内湿度が目標設定湿度よりも高く、その高い湿度を下げようとしても、圧縮機の周波数が増加しないので、目標設定湿度に到達しないことになる。
【００８２】
従って、室内湿度と設定湿度との湿度差がある一定値以上である場合は、室温と設定温度との温度差もある一定値以上あるか無いかを判断し、この判断結果で、温度差が所定値以上の場合は、その温度差に基づいて制御し、温度差が所定値以上ない場合は、予め設定された各温度差と各湿度差に対する補正表から補正値を求め、この求めた補正値で検出温度差を補正し、この補正した温度差に基づいて圧縮機の周波数を制御するようにする。
【００８３】
なお、このようにすると、室内の湿度を確実に目標設定湿度にできるようになるため、室内を快適な湿度にする信頼性の高い空気調和機が得られる。
【００８４】
実施の形態６．
この実施の形態６は、実施の形態１から５の構成と動作において、第２の絞り調整機構３の入口側と出口側に設けられ、当該第２の絞り調整機構３の入口側と出口側の温度又は圧力に相当する特性値を検出する詰まり検出手段（図示せず）を具備し、再熱除湿運転中の第２の絞り調整機構５の不純物等による詰まりを検出して制御するものである。
【００８５】
次に、この動作について説明する。
まず、第２の絞り調整機構５を介して冷媒を流す再熱運転中に、その開口部に冷媒中の不純物等が詰まりると、冷媒が流れなくなり、第２の絞り調整機構５の入口側と出口側との温度差又は圧力差が接近するので、このことを詰まり検出手段が検出すると、制御手段は、室温が上昇したり、圧縮機が過熱運転状態になると判断して、主回路の電磁弁を全開にし、第１、第２の室内熱交換器共に蒸発器として機能する冷房運転に切換えて運転する。
【００８６】
以上説明したように、詰まり検出手段が、前記第２の絞り調整機構の出入口に設けられ、該第２の絞り調整機構の出入口冷媒の温度又は圧力に相当する特性値から詰まり状態を検出するので、第２の絞り調整機構の詰まり状態が解るようになるため、信頼性が向上した空気調和機が得られる。
【００８７】
また、制御手段が、詰まり検出手段から前記第２の絞り調整機構の詰まり信号を受信した時、前記第１の室内熱交換器から前記第２の室内熱交換器へ冷媒が流れるように前記主回路の開閉弁を開くので、室温が上昇したり、圧縮機が過熱運転状態で運転されないようになるため、故障が少なく、室内を快適な温度にする信頼性の高い空気調和機が得られる。
【００８８】
また、以上説明した実施の形態２から６における冷凍機油として、冷媒と溶け合わない所謂非相溶油（例えばアルキルベンゼン油）を用いると、電磁弁の内部に冷凍機油が溜まらなくなり、冷媒が冷凍機油に寝込まなくなるので、弁部分でのホーミング現象等による開閉動作の妨げを防ぐことができるようになるので、冷房運転から再熱除湿運転に確実に切換えられる信頼性が向上した空気調和機が得られる。。
【００８９】
また、以上説明した実施の形態１から６における冷媒は、単一冷媒のＲ３２、又は非共沸混合のＲ４１０Ｃ、Ｒ４０７Ｃ、又は炭化水素系冷媒のＲ５０やＲ６００等でも良い。
【００９０】
【発明の効果】
この発明の空気調和機によれば、制御手段が、冷房運転から再熱除湿運転になった時、室内相対湿度が目標相対湿度よりも高い場合には、圧縮機の回転数を冷房運転終了時の圧縮機の回転数より上昇させ、室内相対湿度が目標相対湿度よりも低い場合には、圧縮機の回転数を冷房運転終了時の圧縮機の回転数より減少させるように制御するとともに、第１の絞り調整機構の開度を制御して、第１の室内熱交換器の加熱能力と第２の室内熱交換器の冷却能力との割合が室内の顕熱負荷と潜熱負荷との割合に合うように再熱除湿運転を行うので、室内温度を目標設定温度に維持して室内相対湿度をスピーディに目標相対湿度にするようになって、室内をスピーディに快適な温・湿度にすることができ、また、室内負荷が変化しても、この変化に追従して室内を快適な温・湿度にすることができる使い勝手が良く、信頼性の高い空気調和機が得られる。
【００９７】
また、再熱除湿運転を行っている時に、外気温度が変化した場合には、制御手段が、その変化に対応して室外熱交換器のファンの回転数を制御し第１の室内熱交換器の加熱能力を変化させ、第１の室内熱交換器の加熱能力と第２の室内熱交換器の冷却能力との割合が室内の顕熱負荷と潜熱負荷との割合に合うようにするので、外気温度が変化しても対応でき、更に信頼性の高い空気調和機が得られる。
【００９８】
また、再熱除湿運転を行っている時に、室内温度が目標設定温度より高くなって、室内相対湿度が目標相対湿度よりも高い場合には、制御手段が、第１の絞り調整機構の開度を絞って、第１の室内熱交換器の凝縮温度を室内温度以下として第１の室内熱交換器の加熱能力をゼロとするので、第１の室内熱交換器を通過する空気を加熱しないで無駄なエネルギーを供給することなく、室内を快適な温・湿度にする信頼性の高い空気調和機が得られる。
【図面の簡単な説明】
【図１】この発明の実施の形態１、２における概略構成図である。
【図２】この発明の実施の形態１における第１の絞り調整機構の開度を変化させたモリエル線図である。
【図３】この発明の実施の形態１における空気側と冷媒側の関係を示す関連図である。
【図４】この発明の実施の形態１における空気側と冷媒側の関係を示す関連図である。
【図５】この発明の実施の形態１、２における第１の絞り調整機構の開度と冷凍サイクルの関係をモリエル線図上に示した図である。
【図６】この発明の実施の形態１、２における第１の絞り調整機構の開度に対する顕熱と潜熱能力（負荷）との関係を示した図である。
【図７】この発明の実施の形態３における室外ファンの回転数と冷凍サイクルの関係をモリエル線図上に示した図である。
【図８】この発明の実施の形態３における圧縮機及び室外ファンの回転数に対する顕熱と潜熱能力（負荷）との関係を示した図である。
【図９】この発明の実施の形態１、２における第１の絞り調整機構の開度に対する顕熱と潜熱能力（負荷）との関係を示した図である。
【図１０】この発明の実施の形態１、２における冷房から再熱へ切換えた時の第１の絞り調整機構（圧縮機の回転数）、及び室外ファンの回転数の相関図である。
【図１１】従来の概略構成図である。
【図１２】従来の室内ファン制御の説明図である。
【符号の説明】
１圧縮機、２室外熱交換器、３第１の絞り調整機構、４第１の室内熱交換器、５第２の絞り調整機構、６第２の室内熱交換器、７室内送風機、８室外送風機、９室内制御部、１０室外制御部、１１湿度センサー、１２室温センサー、１３室内凝縮温度センサー、１４室内蒸発温度センサー、１５外気温センサー、１６リモコン受光部、１７リモコン。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an air conditioner, and more particularly to an air conditioner that makes room temperature and humidity comfortable.
[0002]
[Prior art]
As shown in FIG. 11, the conventional air conditioner has a compressor 1, a four-way switching valve, an outdoor heat exchanger 2, a first throttle adjustment mechanism 3, a first indoor heat exchanger 4, and a solenoid valve. The main circuit and the second indoor heat exchanger 6 are sequentially connected by piping, and the second throttle adjuster 5 is connected by piping in parallel with the main circuit having the solenoid valve, thereby constituting a refrigeration cycle. During the cooling operation of the refrigeration cycle, the solenoid valve is opened so that the refrigerant flows through the main circuit without passing through the second throttle adjustment mechanism 5, and the first indoor heat exchanger 4 and the second indoor heat exchanger 6 are opened. Let it function as an evaporator and cool it.
[0003]
In the dehumidifying operation that mainly reduces the indoor relative humidity, the first throttle adjustment mechanism is fully opened and the solenoid valve of the main circuit is closed, so that the first indoor heat exchanger 4 functions as a condenser (heater). The second indoor heat exchanger 6 functions as an evaporator so that the refrigerant is throttled by the second throttle adjusting mechanism 5 and overheated by one first indoor heat exchanger 4 while the other second The indoor air heat exchanger 6 cools the passing air, and then mixes the cooled air with the heated air so as to perform a dehumidifying operation mainly based on sensible heat without lowering the room temperature. Met.
[0004]
However, in the case where the first throttle adjusting mechanism is fully opened and the second throttle adjusting mechanism 5 is used to perform the dehumidifying operation by reducing the refrigerant, the compressor according to the room temperature (sensible heat load). When the frequency of the compressor is increased, a refrigerant sound is generated from the second throttle adjustment mechanism 5 at a certain frequency or higher due to the relationship of the refrigerant flow velocity. Therefore, after the compressor frequency is increased to a predetermined frequency at which no refrigerant noise is generated, The rotational speed of the fan 8 was increased to cope with the high relative humidity in the room.
That is, since the rotational speed of the outdoor fan 8 is increased to increase the high pressure and the compressor is operated at a high compression ratio, the discharge temperature of the compressor is increased and power consumption is increased.
[0005]
In addition, as shown in FIG. 12, the frequency of the compressor 1 and the frequency of the outdoor fan 8 are such that the dehumidifying operation is performed by increasing the rotational speed of the outdoor fan 8 while keeping the frequency of the compressor 1 constant. When the number of rotations is determined, the sensible heat capacity and the latent heat capacity are determined, respectively, and control is performed so that the room temperature and humidity correspond to each of the determined sensible heat capacity and latent heat capacity.
[0006]
Therefore, when the latent heat capacity is determined by setting the room humidity to a certain target set humidity, the room temperature is controlled by the sensible heat capacity corresponding to the determined latent heat capacity, and conversely, the room temperature is manifested by trying to set the target temperature to the target set temperature. When the heat capacity is determined, the room humidity is controlled by the latent heat capacity corresponding to the determined sensible heat capacity, so it is difficult to set the indoor temperature and humidity to the target temperature and humidity.
[0007]
In other words, when the sensible heat capacity or latent heat capacity of the air conditioner at that time is equal to the indoor latent heat load or the indoor sensible heat load, the room temperature and humidity can be set to the target set temperature and humidity. When one of these becomes the target value, the other value does not become the target value, but simply maintains the indoor state at a value that is commensurate with the other ability.
[0008]
Therefore, when the room temperature is high even though the room temperature is at the appropriate target set temperature, such a device reduces the rotational speed of the outdoor fan 8 and reduces the first indoor heat in order to reduce the room humidity. Since the temperature of the exchanger is raised to increase the amount of heating, the room temperature rises, so the number of revolutions of the compressor must be increased, and the amount of heating further increases by the amount of this number of revolutions. The number of rotations of the outdoor fan 8 needs to be increased again by the amount of heating, and this is difficult because the number of rotations of the compressor and the number of rotations of the outdoor fan 8 must be predicted and controlled. Not only is the control forced, the accuracy is low, and the latent heat capacity is not taken into consideration, so the latent heat capacity cannot be balanced against the latent heat load, and the power consumption is increased by the increase in the compressor speed. Too large It was casting.
[0009]
Further, in the case where the frequency of the compressor is not fixed and the refrigerant sound of the second throttle adjusting mechanism 5 is increased by the rotational speed of the indoor fan 7 and masked by the blowing sound, that is, the compressor In the case where the frequency and the wind speed of the indoor fan 7 are increased, as shown in FIG. 12, the evaporation capacity and the evaporation temperature increase and the sensible heat ratio increases, so that the sensible heat capacity contributing to the decrease in the indoor temperature increases. However, the latent heat capability contributing to the decrease in the absolute humidity in the room hardly increases, and as a result, the operation is performed with the dehumidification performance lowered, so the room humidity cannot be set to the target set humidity.
[0010]
Moreover, in the reheat dehumidification operation in these conventional air conditioners, the second throttle adjustment mechanism 5 is set to a fixed opening for economic reasons, and therefore the outlet of the second indoor heat exchanger (evaporator). The so-called suction superheat (superheat degree), which is the temperature difference between the refrigerant temperature and the suction refrigerant temperature of the compressor, changes as the frequency of the compressor changes.
[0011]
Therefore, for example, this is because the throttle of the second throttle adjusting mechanism 5 prevents the refrigerant liquid from returning to the compressor while ensuring the heat exchange capability of the second indoor heat exchanger (evaporator) 6. Even if the amount, that is, the degree of superheat is set in accordance with the low frequency band, after that, when the frequency of the compressor is increased from the relationship of the indoor load and the refrigerant circulation amount is increased, the throttle is excessively reduced, The refrigerant temperature at the outlet of the heat exchanger became overheated, the temperature of each part of the compressor increased, and the compressor was damaged.
[0012]
Conversely, when the throttle amount (superheat degree) of the second throttle adjustment mechanism 5 is set to a high frequency band, the frequency of the compressor is lowered due to the indoor load, and the refrigerant circulation amount is reduced. Since the liquid refrigerant returned to the compressor 1, the compressor was damaged or the dehumidification performance was lowered.
[0013]
In addition, since the opening area of the second diaphragm adjusting mechanism 5 in these reheat dehumidifying operations is generally smaller than the opening area of the first diaphragm adjusting mechanism 3, impurities and the like are easily clogged. Since the reheat dehumidification operation is continued even if the refrigerant circulation decreases and the refrigerant superheat degree of the compressor increases, various troubles of the compressor generated due to the clogging operation also occur.
[0014]
Another conventional example is disclosed in Japanese Patent Laid-Open No. 6-137711. However, in such a cooling operation, the capacity of the compressor is controlled according to the indoor temperature (sensible heat load) for the purpose of lowering the indoor temperature during the cooling operation, and according to the indoor humidity during the dehumidifying operation. Since the capacity of the compressor is controlled, the control method of the compression function force during the cooling operation and the dehumidifying operation is different and complicated control is performed.
[0015]
[Problems to be solved by the invention]
Since the conventional air conditioner is configured as described above, it is difficult to set the room temperature and relative humidity to the target temperature and humidity.
[0016]
In the case of increasing the fan speed in the room during the dehumidifying operation and masking the refrigerant sound of the second throttle adjusting mechanism 5, the sensible heat ratio increases as the wind speed increases and the room temperature decreases. There was a problem that the performance was lowered.
[0017]
In addition, even if impurities or the like are clogged in the second throttle adjusting mechanism and the degree of superheat increases, the dehumidifying cooling operation is continued, which causes a problem of the compressor.
[0018]
The present invention has been made to solve such a problem, and even if various load conditions at the time of cooling and heating are changed, the indoor temperature and humidity can be quickly set to the target temperature and humidity, and the reliability for comforting the room. It aims at obtaining a high air conditioner.
[0019]
In addition, the present invention provides an air conditioner that is easy to use and makes the room comfortable by automatically performing a cooling operation or a reheat dehumidifying operation based on the indoor temperature, the target temperature, and the temperature difference. With the goal.
[0020]
It is another object of the present invention to obtain a highly reliable air conditioner that can prevent a trouble of each device and comfort the room.
[0021]
[Means for Solving the Problems]
Air conditioner of this invention Is , Compressor, outdoor heat exchanger The second 1 throttle adjustment mechanism, first indoor heat exchanger, second throttle adjustment mechanism The second 2 indoor heat exchangers are connected by pipes sequentially, Cooling operation in which both the first indoor heat exchanger and the second indoor heat exchanger function as an evaporator, the first indoor heat exchanger as a condenser, and the second indoor heat exchanger as an evaporator Reheat and dehumidify operation to reduce the relative humidity in the room Air conditioner Because , When the control means changes from the cooling operation to the reheat dehumidifying operation, if the indoor relative humidity is higher than the target relative humidity, the rotational speed of the compressor is increased from the rotational speed of the compressor at the end of the cooling operation, When the indoor relative humidity is lower than the target relative humidity, the compressor rotational speed is controlled to be lower than the compressor rotational speed at the end of the cooling operation, and Controlling the opening of the first aperture adjustment mechanism No. 1 indoor heat exchange Vessel heating Capacity and cooling capacity of the second indoor heat exchanger And ratio Is indoors Ratio of sensible heat load and latent heat load In To fit Perform reheat dehumidification operation Is.
[0028]
Also, If the outside air temperature changes during reheat dehumidification operation, The control means So In response to changes in Room Control the fan speed of the external heat exchanger The heating capacity of the first indoor heat exchanger is changed, and the ratio between the heating capacity of the first indoor heat exchanger and the cooling capacity of the second indoor heat exchanger is Division of indoor sensible heat load and latent heat load Go together Like Do Is.
[0029]
Also, If the room temperature is higher than the target set temperature and the room relative humidity is higher than the target relative humidity during reheat dehumidification operation, The control means The opening degree of the first throttle adjustment mechanism is throttled so that the condensation temperature of the first indoor heat exchanger is equal to or lower than the indoor temperature, and the heating capacity of the first indoor heat exchanger is set to zero. Is.
[0034]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
1 is a schematic configuration diagram of an air conditioner according to Embodiment 1 of the present invention, in which 1 is a compressor, 2 is an outdoor heat exchanger, and 3 is a first throttle such as an electric expansion valve. Adjustment mechanism, 4 is a first indoor heat exchanger, 5 is a second throttle adjustment mechanism comprising a fixed opening orifice, capillary, electric expansion valve, etc., 6 is a second indoor heat exchanger, and 7 is a room A blower 8 is an outdoor blower.
Note that the second throttle adjustment mechanism 5 provided between the first indoor heat exchanger and the second indoor heat exchanger in this figure has a porous body that silences the refrigerant sound passing therethrough. The main circuit is provided with an electromagnetic valve 6 that is open in the cooling operation and closed in the dehumidifying operation in parallel with the second throttle adjusting mechanism 5.
[0035]
In this figure, 11 is an indoor humidity detecting means for detecting the relative humidity in the room, 12 is a room temperature sensor for detecting the indoor temperature provided in the room, and 13 is the first indoor heat exchanger 4. The first inlet temperature sensor for detecting the inlet temperature of the heat exchanger, 14 is provided in the second indoor heat exchanger 4, and the second inlet temperature for detecting the inlet temperature of the heat exchanger Sensor, 15 is an outside air temperature sensor, 16 is provided on the outer surface of the indoor unit, and receives a signal from a remote controller 17, and a remote control light receiving unit (not shown), 17 is an indoor target temperature / humidity, cooling / heating, It is a remote controller that instructs an operation mode such as a reheat dehumidifying operation.
[0036]
Further, 9 in this figure is provided in the indoor unit, and controls each device in the indoor unit (for example, the indoor fan 7, the second aperture adjustment mechanism 5 and the like) based on the signals from the respective sensors, The indoor microcomputer 10 communicates with the outdoor microcomputer 10, and 10 is provided in the outdoor unit, communicates with the outdoor microcomputer 10, and each device (for example, the compressor 1 and the outdoor fan) in the outdoor unit based on signals from the respective sensors. 8 and the opening degree of the first aperture adjustment mechanism 3), and the control means (not shown) includes the outdoor microcomputer 10 and the indoor microcomputer 9.
[0037]
Next, the operation thus configured will be described.
First, in the reheat dehumidifying operation for reducing the dehumidification of the indoor air, the control means closes the electromagnetic valve of the main circuit, and the refrigerant is supplied from the first indoor heat exchanger through the second throttle adjusting mechanism 5 to the second A second air flow that adjusts the opening degree of the first throttle adjustment mechanism 3 and functions as an evaporator so that the first indoor heat exchanger functions as a condenser while flowing to the indoor heat exchanger. The (evaporation) temperature of the indoor heat exchanger 6 is set to be equal to or lower than the dew point temperature of the room air, and cooling and dehumidification are performed while cooling the room passing air.
[0038]
At this time, if the evaporation temperature is lowered too much in order to increase the cooling and dehumidification, the temperature of the room air will also drop, and the room temperature may fall below the target set temperature. Therefore, a part of the passing indoor air is heated by the first indoor heat exchanger 4 functioning as a condenser, and the remainder of the passing indoor air is passed through the second indoor heat exchanger 6 functioning as an evaporator. Then, these passing room airs are mixed, adjusted to an appropriate temperature and humidity, and then blown into the room from the outlet.
[0039]
In this dehumidifying and cooling operation, the indoor heat exchanger is divided into the first and second indoor heat exchangers 4 and 6 as described above, and in particular, only the second indoor heat exchanger is an evaporator. Since the cooling capacity of the evaporator is about half and the heat dissipation capacity of the condenser is increased, the control is performed in consideration of this.
[0040]
Therefore, for example, in the inverter (rotation speed of the compressor) control that balances the indoor load and the device capacity, the rotation of the compressor and the outdoor fan at the end of the cooling operation when the indoor temperature reaches the target set temperature. When switching to the dehumidifying and cooling operation with a number, as described above, the first indoor heat exchanger 4 functions as a condenser, so that the heat radiation amount (condensing capacity) of the condenser in the refrigeration cycle increases, and the first Heating by the indoor heat exchanger 4 and the heat exchanging capacity of the evaporator decreases, and the indoor temperature rises. In order to prevent this, the rotation speed of the compressor during cooling operation that reaches the target set temperature is determined. Furthermore, the number of revolutions is further increased, and the necessary heating amount is applied so as to reach the target set humidity while maintaining the room at the target set temperature with the increased capacity, thereby making the room air a comfortable target temperature and humidity. .
[0041]
Also, in the case of so-called thermo-operation control that has a device capacity larger than the indoor load and controls within a predetermined temperature range of the indoor target set temperature, the rotational speed of the outdoor fan is changed to change the capacity of the condenser in order to secure heat dissipation. Although it is necessary to lower it according to (outside air temperature change), the compressor capacity is higher than the indoor load, so the compressor does not increase at room temperature even if it is operated at the end of the cooling operation. It will not be necessary to raise.
[0042]
However, in any case, in order to set the temperature / humidity of the room air to a comfortable target temperature / humidity, the condensation temperature (heating temperature) of the first indoor heat exchanger 4 functioning as heating means is set to the first temperature. The temperature of the second indoor heat exchanger 6 (cooling temperature) that functions as an evaporator via the second throttle adjustment mechanism 5 that is adjusted by the opening degree of the throttle adjustment mechanism 3 and that is a fixed opening degree by this adjustment. Adjusting the cooling capacity, the room air is brought to a comfortable target temperature and humidity while adjusting the heating amount and the cooling amount.
[0043]
Accordingly, at this time, for example, as shown in FIG. 5, the opening degree of the first throttle adjustment mechanism 3 is throttled, and the refrigeration cycle at the time of the throttle is A, and the first throttle adjustment mechanism 3 in the refrigeration cycle A Assuming that the refrigeration cycle when B is further squeezed is B, the refrigeration cycle B with a large amount of squeezing has less refrigerant supplied to the first indoor heat exchanger 4 than the refrigeration cycle A with a small squeezing amount. Further, since the heating temperature at that time is also lowered to be close to room temperature, the heat exchange capacity is significantly reduced and the heating power is greatly reduced, so that the ratio of the cooling capacity to the heating capacity is increased. Also, if this reverse operation is performed, the ratio of the cooling capacity to the heating capacity decreases, so the opening degree of the first aperture adjustment mechanism 3 is increased or decreased, as shown in FIG. In addition, the ratio of the heating capacity (sensible heat) and the cooling capacity (sensible heat + latent heat), that is, the ratio of the sensible heat capacity and the latent heat capacity is adjusted so as to match the sensible heat load and the latent heat load in the room. To a comfortable target temperature and humidity.
[0044]
In other words, the first throttle adjusting mechanism 3 is squeezed to set the condensation temperature of the first indoor heat exchanger 4 to room temperature or lower to reduce the heating amount to zero or to increase the room temperature to room temperature or higher to reduce the room air. Use comfortable target temperature and humidity.
If the heating amount is reduced to room temperature or lower and the heating amount is zero, the gradient of the latent heat and sensible heat, which are the ratio of the room temperature, humidity, and ratio, is a function of only the evaporation temperature, as shown in FIG. By adjusting the opening of the mechanism 3 and adjusting the evaporation temperature, the ratio between the latent heat capacity and the sensible heat capacity of the air conditioner can be controlled without heating with excess energy.
[0045]
Next, based on the above, for example, when the room temperature is equal to or higher than the target set temperature (for example, 28 ° C. relative to the target set temperature 25 ° C.) and the relative humidity is high (80% or higher), as shown in FIG. The opening degree of the first throttle adjustment mechanism 3 is throttled so that the condensation temperature of the first indoor heat exchanger 4 is not more than room temperature, that is, the heating amount is substantially zero and cooling is mainly performed, 2, the evaporation temperature of the indoor heat exchanger 6 is changed from A to B, and the target temperature / humidity gradient (SHF) with respect to the indoor temperature / humidity is changed from A to B as shown in FIG.・ Make the humidity on the SHF (sensible heat ratio line) so that the equipment capacity and the indoor load are combined to make the room a comfortable target temperature and humidity.
[0046]
In the case where the amount of heating is zero, the first throttle adjustment mechanism 3 is throttled, so that the evaporation temperature decreases, the temperature difference from room temperature increases, and the heat exchanger capacity increases, but the refrigerant circulation Since the amount is greatly reduced and the cooling capacity is reduced, the room absolute humidity is mainly lowered without much lowering the room temperature, so that the indoor relative humidity is lowered.
[0047]
Also, during this control, if the outside air temperature rises or the room temperature rises due to indoor heat generating objects (such as the number of indoor personnel), the outdoor fan speed is increased so that the high pressure (heating state) does not change. The target temperature / humidity is on the SHF (sensible heat ratio line) by adjusting the opening of the first throttle adjustment mechanism 3 Control to get on.
[0048]
Further, when the room temperature is substantially the target set temperature (25 ° C.) and the relative humidity is high (80% or higher), the first throttle adjusting mechanism 3 is set so that the temperature of the first indoor heat exchanger 4 is higher than the room temperature. While controlling the opening and adjusting the heating amount to maintain the room temperature, the room humidity is set to the target set humidity.
[0049]
That is, when the room temperature is substantially the target set temperature and the humidity is high, as shown in FIG. 5, the humidity is lowered mainly by the heating power, so that the condensation temperature of the first indoor heat exchanger 4 is slightly higher than room temperature. In order to lower the indoor humidity by adjusting the opening degree of the first diaphragm adjusting mechanism 3 so as to be higher, the room temperature is not increased by this heating force while slightly heating in the first indoor heat exchanger 4. The heating power is canceled by the sensible heat capacity of the cooling capacity of the second indoor heat exchanger 6 to reduce the relative humidity while preventing the indoor temperature from decreasing, so that the room has a comfortable target temperature and humidity. .
[0050]
In order to cancel the heating power with the sensible heat cooling capacity of the second indoor heat exchanger 6, the heat exchange capacities (capabilities) of the first and second indoor heat exchangers are almost the same. The temperature difference between the room temperature and the temperature of the first indoor heat exchanger 4 may be made substantially the same as the temperature difference between the room temperature and the temperature of the second indoor heat exchanger 6. That is, the processing may be performed in consideration of the temperature difference ratio based on the capacity ratio of the first and second indoor heat exchangers.
[0051]
In addition, when the room temperature is lower than the target set temperature (25 degrees), for example, 23 ° C., in other words, when the room absolute humidity that does not feel much sultry heat is low, as shown in FIG. As shown in FIG. 3, the heating amount is increased as shown in FIG. 3 while the opening of the throttle adjusting mechanism 3 is fully opened to prevent the temperature of the second indoor heat exchanger 6 from lowering the room temperature. The heating power (condensation temperature = outside air temperature + about 15 ° C.) sets the room temperature to the target set temperature and lowers the indoor relative humidity to make the room a comfortable target temperature / humidity.
In other words, when the indoor temperature and absolute humidity are low and it does not feel too humid, the outside temperature is low and the COP of the refrigeration cycle is good (consumption power for cooling capacity is low). Reduces relative humidity, mainly force.
Further, when the room temperature is much lower than the target set temperature and it is desired to lower the room humidity, the operation may be switched to the heating operation.
[0052]
When the above control is performed, naturally, as shown in FIG. 4, a saturation temperature line (relative humidity 100%) line connecting the room temperature / humidity and the target temperature / humidity on the air diagram. When the dry-bulb temperature at the point of contact falls below 5 ° C, for example, not only the cooling capacity of the air conditioner decreases, but also frost may be formed due to fluctuations in the outside air temperature. Like that.
That is, for example, when the temperature reaches 0 ° C., which is 5 ° C. or less, the line connecting the saturation humidity point of 5 ° C. and the target temperature / humidity collides with the sensible heat line of the room temperature / humidity (of the first indoor heat exchanger). The temperature of the first indoor heat exchanger is set so that the required heating power is obtained from the enthalpy difference between this point and the room temperature / humidity, and the required heating power is obtained. The opening degree of the first throttle mechanism is controlled.
[0053]
In general, the ratio of the heat radiation capacity (condensation capacity) to the cooling capacity (cooling capacity) of the refrigeration cycle during the cooling operation is approximately 1.3 at CT = 45 ° C. and ET = 10 ° C. During the dehumidifying operation, the first indoor heat exchanger 4 becomes a condenser and the heat radiation capacity is further increased, so that the condensation temperature is lowered and the evaporation temperature is lowered accordingly. Therefore, the opening of the first throttle adjustment mechanism 3 is fully opened. However, in this case, as described later, the rotational speed of the outdoor fan is decreased or the rotational speed of the compressor 1 is increased.
[0054]
Furthermore, as described above, since it is common to determine the area ratio between the condenser and the evaporator according to the ratio (1.3) of the condensation capacity to the cooling capacity, the first functioning as a condenser. When the area ratio of the second indoor heat exchanger 6 to the indoor heat exchanger 4 is set to 1 or more, it is almost the same as increasing the condensation temperature by lowering the rotational speed of the outdoor fan, and the outdoor air temperature decreases. However, since it becomes possible to cope with it, a user-friendly air conditioner can be obtained.
[0055]
In addition, in the case where the throttle amount is increased, the refrigerant accumulates in the outdoor heat exchanger 2, so that the pressure (temperature) on the outdoor heat exchanger side slightly increases and the temperature of the first indoor heat exchanger also increases. Therefore, it goes without saying that control is performed in consideration of these matters.
[0056]
In the cooling operation or heating operation other than the reheat dehumidifying operation, the refrigerant flows through the main circuit without flowing through the second throttle adjustment mechanism, and both the first and second indoor heat exchangers 4 and 6 The operation is performed by functioning as an evaporator or a condenser.
[0057]
As described above, in the air conditioner that reheats and dehumidifies indoor air, the control means controls the opening of the first throttle adjustment mechanism based on the temperature of the first indoor heat exchanger, While adjusting the amount of heating to the indoor air passing through the first indoor heat exchanger, the ratio between the latent heat capacity and the sensible heat capacity of the air conditioner was made to substantially match the ratio of the sensible heat load and the latent heat load in the room. Therefore, even if the indoor load changes, the indoor temperature is set to the target temperature / humidity state following this change, so that a highly reliable air conditioner that makes the indoor temperature / humidity comfortable can be obtained.
[0058]
Further, the control means opens the first throttle adjustment mechanism so that the temperature of the first indoor heat exchanger becomes equal to or higher than the temperature of the indoor air when the temperature of the indoor air is equal to or lower than a target set temperature. Since the air temperature is controlled, a highly reliable air conditioner can be obtained in which the indoor temperature is reliably set to the target temperature and the room temperature and humidity are comfortable while the air passing through the first indoor heat exchanger is overheated.
[0059]
Further, the control means opens the first throttle adjustment mechanism so that the temperature of the first indoor heat exchanger becomes equal to or lower than the temperature of the room air when the temperature of the room air is equal to or higher than a target set temperature. Since the air temperature is controlled, a highly reliable air conditioner that provides a comfortable temperature and humidity in the room without supplying unnecessary energy without overheating the air passing through the first indoor heat exchanger can be obtained. .
[0060]
Embodiment 2. FIG.
1 is a schematic configuration diagram of an air conditioner according to Embodiment 1 of the present invention, in which 1 is a compressor, 2 is an outdoor heat exchanger, and 3 is a first throttle such as an electric expansion valve. Adjustment mechanism, 4 is a first indoor heat exchanger, 5 is a second throttle adjustment mechanism comprising a fixed opening orifice, capillary, electric expansion valve, etc., 6 is a second indoor heat exchanger, and 7 is a room A blower 8 is an outdoor blower.
Note that the second throttle adjustment mechanism 5 provided between the first indoor heat exchanger and the second indoor heat exchanger in this figure has a porous body that silences the refrigerant sound passing therethrough. The main circuit is provided with an electromagnetic valve 6 that is open in the cooling operation and closed in the dehumidifying operation in parallel with the second throttle adjusting mechanism 5.
[0061]
In this figure, 11 is an indoor humidity detecting means for detecting the relative humidity in the room, 12 is a room temperature sensor for detecting the indoor temperature provided in the room, and 13 is the first indoor heat exchanger 4. The first inlet temperature sensor for detecting the inlet temperature of the heat exchanger, 14 is provided in the second indoor heat exchanger 4, and the second inlet temperature for detecting the inlet temperature of the heat exchanger Sensor, 15 is an outside air temperature sensor, 16 is provided on the outer surface of the indoor unit, and receives a signal from a remote controller 17, and a remote control light receiving unit (not shown), 17 is an indoor target temperature / humidity, cooling / heating, It is a remote controller that instructs an operation mode such as a reheat dehumidifying operation.
[0062]
Further, 9 in this figure is provided in the indoor unit, and controls each device in the indoor unit (for example, the indoor fan 7, the second aperture adjustment mechanism 5 and the like) based on the signals from the respective sensors, The indoor microcomputer 10 communicates with the outdoor microcomputer 10, and 10 is provided in the outdoor unit, communicates with the outdoor microcomputer 10, and each device (for example, the compressor 1 and the outdoor fan) in the outdoor unit based on signals from the respective sensors. 8 and the opening degree of the first aperture adjustment mechanism 3), and the control means (not shown) includes the outdoor microcomputer 10 and the indoor microcomputer 9.
[0063]
Next, the operation thus configured will be described.
First, during the cooling operation, the control means closes the second throttle adjustment mechanism 5 and opens the electromagnetic valve of the main circuit, so that the first and second indoor heat exchangers 4 and 6 function as an evaporator, The room is cooled while controlling the amount of refrigerant only by the throttle adjusting mechanism 3.
At this time, the control means controls the rotational speed of the compressor based on the temperature difference between the room temperature and the target set temperature so that the room temperature quickly reaches the target set temperature.
[0064]
Next, when the room temperature reaches the target set temperature, the control means closes the solenoid valve of the main circuit, so that the refrigerant passes through the second throttle adjustment mechanism 5 and the second indoor heat from the first indoor heat exchanger. The opening of the first throttle adjusting mechanism 3 is adjusted so that the first indoor heat exchanger functions as a condenser, and the first throttle adjusting mechanism 3 Air passing through the second indoor heat exchanger 6 by controlling the (evaporation) temperature of the second indoor heat exchanger 6 functioning as an evaporator through the opening degree to be equal to or lower than the dew point temperature of the indoor air. The indoor air that has passed through the first indoor heat exchanger 4 is heated, and the room air is mixed to obtain an appropriate temperature and humidity, and then blown out into the room from the air outlet to reheat dehumidification operation. do.
[0065]
At this time, when switching to the reheat dehumidifying operation in a state where the room temperature is not the target set temperature, that is, the A state where the sensible heat capacity (cooling capacity) in FIG. 10 is insufficient, this reheat dehumidifying operation is performed. Then, since heating power is applied, it takes time to reach the target room temperature. Therefore, the cooling operation is switched to the reheat dehumidification operation after the room temperature has substantially reached the target set temperature. In other words, when the room temperature and the target set temperature in FIG. 10 are approximately equal to the B or C state, the cooling operation is switched to the reheat dehumidification operation.
[0066]
Even if the room temperature is equal to the target set temperature, when the compressor speed at the target set temperature is equal to or higher than the predetermined speed, a heating power is applied in the reheat dehumidifying operation, and as described above, the compressor Because it is necessary to increase the number of rotations, the device capacity becomes insufficient with respect to the indoor load, or the temperature difference between the outside air temperature and the room temperature (indoor sensible heat load) is large. It is judged that the relative humidity in the room will be reduced if the absolute humidity is taken compared to the one with a small load), and the control means judges that it is not necessary to lower the relative humidity of the room air, so there is no switching from the cooling operation to the reheat dehumidification operation. .
[0067]
Next, in this reheat dehumidifying operation, the indoor heat exchanger is divided into the first and second indoor heat exchangers 4 and 6 as described above, and in particular, only the second indoor heat exchanger is evaporated. Since the cooling capacity of the evaporator is about half and the heat dissipation capacity of the condenser is increased, control is performed in consideration of this.
[0068]
Therefore, for example, in the case of the present invention that balances the indoor load and the apparatus capacity by controlling the inverter (rotation speed of the compressor), the compressor and the outdoor fan at the end of the cooling operation when the indoor temperature becomes the target set temperature. As described above, the first indoor heat exchanger 4 functions as a condenser to warm the passing air, and the condenser capacity (heat dissipation capacity) is increased. Since the evaporator capacity decreases, the room temperature rises, and in order to prevent this, the number of revolutions is increased further than the compressor speed during the cooling operation when the target set temperature is reached. While maintaining the room at the target set temperature, a necessary heating amount is applied so as to achieve the target set humidity so that the room air has a comfortable target temperature and humidity.
[0069]
That is, for example, when the indoor relative humidity is higher than the target relative humidity, the first indoor heat exchanger is changed from the evaporator to the condenser, the indoor air is heated, and the cooling capacity of the heat exchanger is further reduced. To increase the compressor speed, and when the indoor relative humidity is lower than the target relative humidity, the compressor speed is decreased, and at the same time, the compressor speed is maintained. Control.
[0070]
In other words, in the case of changing the opening of the first throttle adjustment mechanism based on the outlet refrigerant temperature of the second indoor heat exchanger 6 as in the present invention, the rotation speed of the compressor is changed, By changing the refrigerant circulation amount, the outlet refrigerant temperature of the second indoor heat exchanger 6 changes, the capacity ratio of the evaporation capacity and the condensation capacity of the refrigeration cycle also changes, and the heating power (temperature) of the first indoor heat exchanger Therefore, considering this, first, the amount of cooling capacity reduction described above, that is, the rotation speed of the compressor for maintaining the indoor target set temperature is obtained, and then the humidity of the indoor air is controlled. As shown in FIG. 3, the heating amount corresponding to the cooling capacity increase for extracting the heating power, in other words, the heating amount corresponding to this cooling capacity increase is obtained from the required heating amount on the air side, and the compression corresponding to this required heating amount. Find the speed of the machine Thereafter, the obtained number of revolutions is added to the number of revolutions of the compressor at the target set temperature to control it, and as shown in FIGS. 6 and 9, it is adjusted to the indoor load via the opening of the first throttle adjustment mechanism. .
[0071]
In this control, when the outside air temperature (condensation temperature) is low or high and the heating power is insufficient or too much, the rotation speed of the outdoor fan is changed according to the outside air temperature or the like. .
[0072]
As described above, since the cooling operation is switched to the reheat dehumidifying operation when the room temperature reaches the target temperature, the room temperature is automatically set to the target humidity by maintaining the room temperature at the target temperature. Therefore, it is possible to obtain an easy-to-use air conditioner that provides a comfortable and comfortable temperature and humidity in the room.
[0073]
Embodiment 3 FIG.
In the third embodiment, when the reheat dehumidifying operation is performed in the configuration and operation of the first and second embodiments, the outside air temperature or the indoor load changes, and as a result, the temperature of the outdoor heat exchanger 2 or When the ratio between the indoor sensible heat load and the latent heat load changes, the rotational speed of the outdoor fan 8 is controlled to maintain the temperature (heating power) of the first indoor heat exchanger or change the heating power. Is.
That is, when the outside air temperature decreases or increases, or when the ratio of the latent heat load to the indoor sensible heat load increases or decreases, as shown in FIGS. The speed (heating power) of the first indoor heat exchanger as the heating means is changed by lowering or increasing the rotational speed (wind speed) of 8, and the ratio between the indoor sensible heat load and the latent heat load is air-conditioned. It is designed to match the ratio of sensible heat capacity and latent heat capacity of the machine.
[0074]
In such a configuration, when the outdoor fan speed is decreased, the heat radiation capacity of the outdoor heat exchanger 2 is decreased and the condensation temperature is increased as shown in FIG. 7, and heating is performed as the condensation temperature increases. The condensation temperature (heating temperature) of the first indoor heat exchanger 4 as a means also rises, the heat radiation capacity (heating amount) of the indoor heat exchanger 4 increases, and the heat radiation enthalpy difference also changes from the condensation amount B to the condensation amount A. To increase.
Conversely, when the outdoor fan speed is increased, the condensation temperature on the outdoor side decreases and the condensation temperature (heating temperature) of the first indoor heat exchanger 4 as the condenser also decreases, so the temperature difference from the indoor temperature is small. Thus, the heat dissipation capacity (heating amount) of the indoor heat exchanger 4 is reduced, and the heat dissipation enthalpy difference is also reduced.
[0075]
Therefore, when the outdoor temperature closely related to the sensible heat load in the room decreases and the heating power decreases, the outdoor fan speed is decreased, the heating power is increased and balanced, and conversely, the outdoor temperature increases. When the outdoor fan speed is increased and the heating power is decreased and balanced, or when the indoor sensible heat load or latent heat load changes and the ratio between the sensible heat load and the latent heat load changes, As shown in Fig. 7, the rotational speed of the outdoor fan 8 is controlled so that the ratio of the sensible heat capacity and the latent heat capacity of the air conditioner is matched to the ratio of the indoor sensible heat load and the latent heat load to cope with changes in the indoor load. It can be so.
In other words, when the sensible heat ratio line (SHF), which is the gradient of the room temperature / humidity with respect to the indoor target temperature / humidity, changes, the rotational speed of the outdoor fan 8 is controlled to match the changed sensible heat ratio line.
[0076]
As described above, the outdoor fan 8 is controlled so that the ratio between the indoor sensible heat load and the latent heat load substantially matches the ratio between the sensible heat capacity and the latent heat capacity of the air conditioner according to changes in the indoor load and the outside air temperature. Therefore, even if the indoor load or the outside air temperature changes, it becomes possible to cope with it, so that a more reliable air conditioner can be obtained.
[0077]
Embodiment 4 FIG.
In the fourth embodiment, in the configuration and operation of the second embodiment, when switching from the cooling operation to the reheat dehumidifying operation, the compressor is switched after being stopped for a predetermined time.
[0078]
That is, in the fourth embodiment, in the state where the refrigerant is flowing, switching from the reheat dehumidifying operation to the cooling operation, or conversely switching from the cooling operation to the reheat dehumidifying operation, the main circuit on-off valve (solenoid valve) Open or close the control valve because it cannot be opened or closed due to the relationship between the refrigerant differential pressure before and after the on-off valve or the kinetic energy of the refrigerant flow. When the operation mode switching signal is received, the compressor is stopped for a predetermined time, the refrigerant differential pressure and kinetic energy are eliminated, and then the operation mode is changed from the reheating dehumidifying operation to the cooling operation or from the cooling operation to the reheating dehumidifying operation. Is switched.
[0079]
In this case, since the opening / closing operation of the second throttle adjustment mechanism is smooth and the operation mode is surely switched, the air conditioning with high reliability for reliably performing the cooling operation and the reheat dehumidifying operation is performed. A machine is obtained.
[0080]
Embodiment 5 FIG.
In this fifth embodiment, in the configuration and operation of the first to fourth embodiments, the frequency of the compressor during reheating operation is controlled based on the humidity difference between the room humidity and the target set humidity. When the room humidity is higher than the target set humidity despite the target set temperature, the temperature difference is corrected and the frequency of the compressor is controlled.
[0081]
That is, in the fifth embodiment, as shown in FIG. 8, the frequency of the compressor during reheating operation is controlled based on the temperature difference between the room temperature and the set temperature (sensible heat load). If the temperature difference from the set temperature becomes small, for example, the indoor humidity is higher than the target set humidity, and even if an attempt is made to lower the high humidity, the frequency of the compressor does not increase, so the target set humidity is not reached.
[0082]
Therefore, if the humidity difference between the room humidity and the set humidity is greater than a certain value, it is determined whether the temperature difference between the room temperature and the set temperature is greater than a certain value. If the temperature difference is equal to or greater than the predetermined value, control is performed based on the temperature difference. If the temperature difference is not equal to or greater than the predetermined value, a correction value is obtained from a correction table for each temperature difference and humidity difference set in advance. The detected temperature difference is corrected by the value, and the frequency of the compressor is controlled based on the corrected temperature difference.
[0083]
In this case, since the humidity in the room can be surely set to the target set humidity, a highly reliable air conditioner that makes the room a comfortable humidity can be obtained.
[0084]
Embodiment 6 FIG.
The sixth embodiment is provided on the inlet side and the outlet side of the second aperture adjustment mechanism 3 in the configurations and operations of the first to fifth embodiments, and the inlet side and the outlet side of the second aperture adjustment mechanism 3. Is provided with clogging detecting means (not shown) for detecting a characteristic value corresponding to the temperature or pressure, and detecting and controlling clogging caused by impurities in the second throttle adjusting mechanism 5 during the reheat dehumidifying operation. is there.
[0085]
Next, this operation will be described.
First, during the reheating operation in which the refrigerant flows through the second throttle adjustment mechanism 5, if impurities or the like in the refrigerant are clogged in the opening, the refrigerant stops flowing, and the inlet side of the second throttle adjustment mechanism 5 When the clogging detection means detects this, the control means determines that the room temperature has risen or the compressor is in an overheated operation state, and the main circuit The solenoid valve is fully opened, and both the first and second indoor heat exchangers are switched to a cooling operation that functions as an evaporator.
[0086]
As described above, the clogging detection means is provided at the inlet / outlet of the second throttle adjusting mechanism, and detects the clogged state from the characteristic value corresponding to the temperature or pressure of the refrigerant at the inlet / outlet of the second throttle adjusting mechanism. Since the clogged state of the second aperture adjustment mechanism can be understood, an air conditioner with improved reliability can be obtained.
[0087]
In addition, when the control means receives the clogging signal of the second throttle adjustment mechanism from the clogging detection means, the main flow is controlled so that the refrigerant flows from the first indoor heat exchanger to the second indoor heat exchanger. Since the open / close valve of the circuit is opened, the room temperature rises and the compressor is not operated in an overheated operation state, so that a highly reliable air conditioner that can reduce the failure and bring the room to a comfortable temperature can be obtained.
[0088]
Further, when a so-called incompatible oil (for example, alkylbenzene oil) that does not melt with the refrigerant is used as the refrigerating machine oil in the second to sixth embodiments described above, the refrigerating machine oil does not accumulate inside the solenoid valve, and the refrigerant is refrigerating machine oil. The air conditioner with improved reliability that can be reliably switched from the cooling operation to the reheat dehumidification operation can be obtained. It is done. .
[0089]
The refrigerant in the first to sixth embodiments described above may be R32 as a single refrigerant, R410C and R407C as non-azeotropic mixtures, R50 and R600 as hydrocarbon refrigerants, or the like.
[0090]
【The invention's effect】
In the air conditioner of this invention According to the system Means If the indoor relative humidity is higher than the target relative humidity when the cooling operation is changed to the reheat dehumidifying operation, the compressor rotational speed is increased from the compressor rotational speed at the end of the cooling operation, and the indoor relative humidity is increased. When it is lower than the target relative humidity, the compressor is controlled so as to reduce the rotational speed of the compressor from the rotational speed of the compressor at the end of the cooling operation, Controlling the opening of the first aperture adjustment mechanism No. 1 indoor heat exchange Vessel heating Capacity and cooling capacity of the second indoor heat exchanger And ratio Is indoors Ratio of sensible heat load and latent heat load In To fit Perform reheat dehumidification operation So Maintaining the room temperature at the target set temperature and quickly setting the room relative humidity to the target relative humidity, you can quickly and comfortably set the room temperature and humidity. Even if the indoor load changes, Pleasant Make temperature and humidity suitable Easy to use, A highly reliable air conditioner can be obtained.
[0097]
Also, If the outside air temperature changes during reheat dehumidification operation, The control means So To control the fan speed of the outdoor heat exchanger The heating capacity of the first indoor heat exchanger is changed, and the ratio between the heating capacity of the first indoor heat exchanger and the cooling capacity of the second indoor heat exchanger is Division of indoor sensible heat load and latent heat load Go together Like Do Because , Outside Even if the air temperature changes The In addition, a highly reliable air conditioner can be obtained.
[0098]
Also, If the room temperature is higher than the target set temperature and the room relative humidity is higher than the target relative humidity during reheat dehumidification operation, The control means The opening degree of the first throttle adjustment mechanism is throttled so that the condensation temperature of the first indoor heat exchanger is equal to or lower than the indoor temperature, and the heating capacity of the first indoor heat exchanger is set to zero. So Make the room comfortable temperature and humidity without supplying useless energy without heating the air passing through the first indoor heat exchanger A highly reliable air conditioner can be obtained.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram in embodiments 1 and 2 of the present invention.
FIG. 2 is a Mollier diagram in which the opening of the first aperture adjustment mechanism in Embodiment 1 of the present invention is changed.
FIG. 3 is a related diagram showing the relationship between the air side and the refrigerant side in the first embodiment of the present invention.
FIG. 4 is a related diagram showing the relationship between the air side and the refrigerant side in the first embodiment of the present invention.
FIG. 5 is a diagram showing a relationship between the opening degree of the first throttle adjusting mechanism and the refrigeration cycle in the first and second embodiments of the present invention on a Mollier diagram.
FIG. 6 is a diagram showing a relationship between sensible heat and latent heat capability (load) with respect to the opening degree of the first aperture adjustment mechanism in the first and second embodiments of the present invention.
FIG. 7 is a diagram showing a relationship between the rotational speed of an outdoor fan and a refrigeration cycle on a Mollier diagram according to Embodiment 3 of the present invention.
FIG. 8 is a diagram showing a relationship between sensible heat and latent heat capability (load) with respect to the rotational speeds of a compressor and an outdoor fan in Embodiment 3 of the present invention.
FIG. 9 is a diagram showing a relationship between sensible heat and latent heat capability (load) with respect to the opening degree of the first aperture adjustment mechanism in the first and second embodiments of the present invention.
FIG. 10 is a correlation diagram of the first throttle adjustment mechanism (the number of rotations of the compressor) and the number of rotations of the outdoor fan when switching from cooling to reheating in Embodiments 1 and 2 of the present invention.
FIG. 11 is a schematic configuration diagram of the prior art.
FIG. 12 is an explanatory diagram of conventional indoor fan control.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Compressor, 2 Outdoor heat exchanger, 3 1st aperture adjustment mechanism, 4 1st indoor heat exchanger, 5 2nd aperture adjustment mechanism, 6 2nd indoor heat exchanger, 7 Indoor blower, 8 Outdoor Blower, 9 indoor control unit, 10 outdoor control unit, 11 humidity sensor, 12 room temperature sensor, 13 indoor condensation temperature sensor, 14 indoor evaporation temperature sensor, 15 outdoor temperature sensor, 16 remote control light receiving unit, 17 remote control.

Claims

A compressor, an outdoor heat exchanger, a first throttle adjustment mechanism , a first indoor heat exchanger, a second throttle adjustment mechanism , and a second indoor heat exchanger are sequentially connected by piping, and the first indoor heat is Cooling operation in which both the exchanger and the second indoor heat exchanger function as an evaporator, the first indoor heat exchanger as a condenser, and the second indoor heat exchanger as an evaporator An air conditioner that performs a reheat dehumidification operation that lowers the indoor relative humidity , and when the control means changes from the cooling operation to the reheat dehumidification operation, when the indoor relative humidity is higher than the target relative humidity, When the rotational speed of the compressor is increased from the rotational speed of the compressor at the end of the cooling operation and the indoor relative humidity is lower than the target relative humidity, the rotational speed of the compressor is compressed at the end of the cooling operation. controls so as to reduce the rotation speed of the machine, said first aperture By controlling the opening degree of the adjustment mechanism, the ratio between the first heating capacity and the second cooling capacity of the indoor heat exchanger of the indoor heat exchanger fit ratio between indoor sensible heat load and latent heat load An air conditioner characterized by performing a reheat dehumidification operation .

Wherein when performing the reheat dehumidifying operation, when the outside air temperature has changed, said control means, in response to a change of that the outdoor heat exchanger fan speed control to the first of The heating capacity of the indoor heat exchanger is changed, and the ratio between the heating capacity of the first indoor heat exchanger and the cooling capacity of the second indoor heat exchanger is a ratio between the sensible heat load and the latent heat load in the room. the air conditioner according to claim 1, characterized in that the engagement Migihitsuji the case.

Wherein when performing the reheat dehumidifying operation, the indoor temperature is higher than the target setting temperature, if the room relative humidity is higher than the target relative humidity, the control means, prior Symbol of the first aperture adjustment mechanism 2. The air conditioner according to claim 1 , wherein the opening degree is reduced so that the condensation temperature of the first indoor heat exchanger is equal to or lower than the indoor temperature, and the heating capacity of the first indoor heat exchanger is set to zero. Machine.