JP2004144341A

JP2004144341A - Heat pump system

Info

Publication number: JP2004144341A
Application number: JP2002307492A
Authority: JP
Inventors: Jiro Okajima; 岡島　次郎; So Nomoto; 野本　宗; Koryu Watanabe; 渡邊　興隆; So Hiraoka; 平岡　宗; Masaaki Kouchi; 古内　正明; Kei Yanagimoto; 柳本　圭; Takeshi Kawamura; 川村　武志
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2002-10-22
Filing date: 2002-10-22
Publication date: 2004-05-20
Anticipated expiration: 2022-10-22
Also published as: JP3968653B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat pump system of high efficiency, keeping the temperature of the water low, which is flowing into a refrigerant-water heat exchanger by a means of simple constitution. <P>SOLUTION: This heat pump system comprises a heating circulating circuit 62 to which a hot water storage tank 60 and a heat pump 50 for heating the water in the hot water storage tank 60 are connected, a radiated heat circulating circuit 63 where a radiated heat circulating circuit taking-out port 64 at an upper part of the hot water storage tank 60, a radiated heat heat exchanger 67 connected to a load terminal 72, a heat radiating pump 65, a flow rate adjusting valve 66 and a returning part 68 at a predetermined position of the hot water storage tank 60 are successively connected by a pipe 69, a temperature detecting means for detecting the water temperature in the pipe 69 in adjacent to the returning part 68 of the hot water storage tank 60 of the radiated heat circulating circuit 63 and the water temperature at the predetermined position in the hot water storage tank 60, and a control means 101 for controlling the flow rate adjusting valve 66 to adjust the water temperature detected by the temperature detecting means to the predetermined temperature. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
この発明は、ヒートポンプ熱源により貯湯槽の上部より沸き上げ、かつ沸き上げ湯量、水温を制御できる貯湯式給湯器と、風呂追焚、暖房などの負荷端末を接続したヒートポンプシステムに関するものである。
【０００２】
【従来の技術】
貯湯タンクと、圧縮機と、該圧縮機からの冷媒が循環する冷媒用伝熱管と、貯湯タンクからの水が循環する貯湯用伝熱管と、湯船の湯が循環する追焚用伝熱管とにより形成された放熱器と、膨張弁と、該膨張弁からの冷媒と機外空気とを熱交換させる蒸発器とによりヒートポンプ給湯機を構成し、圧縮機からの冷媒が冷媒用伝熱管を介して循環することにより、貯湯タンクから貯湯用伝熱管に循環してきた水を加熱し、当該加熱された水を貯湯タンクに戻すことにより貯湯すると共に、追焚用伝熱管を介して湯船の湯を循環させて冷媒で加熱することにより風呂の追焚を行うようにしている（例えば特許文献１）。
【０００３】
【特許文献１】
特開２００２−１０６９６３号公報（段落００２０−００２７、００５３−００５９、図１）
【０００４】
【発明が解決しようとする課題】
従来のヒートポンプシステムは、追焚回路が冷媒との熱交換においてのみしか稼動できず、貯湯式給湯器での深夜電力時間帯以外の時間帯で追焚負荷が発生したときに追焚できず、また、ヒートポンプがデフロスト運転に入った時にも追焚不能の状態に陥るという問題があった。さらに、給湯と追焚と冷媒との熱交換器が同一であるため、給湯のみ、追焚のみ、給湯追焚同時の３パターンの運転があり、特にＣＯ_２冷媒によるヒートポンプの場合、熱交換器への流入水温が低くないと効率向上が図れないため、追焚からの高い水温が熱交換器に流入すると効率が低下するという問題があった。
【０００５】
この発明は、上記のような問題点を解消するためになされたもので、簡単な構成で、効率の高いヒートポンプシステムを提供することを目的とする。
【０００６】
【課題を解決するための手段】
この発明に係るヒートポンプシステムは、貯湯タンク及びこの貯湯タンクの水を加熱するヒートポンプが接続された加熱循環回路と、前記貯湯タンク上部の取り出し部、負荷端末に接続された熱交換器、ポンプ、主流量調整手段及び前記貯湯タンクのあらかじめ定められた位置の戻し部が順次配管により接続された放熱循環回路と、この放熱循環回路の前記貯湯タンクの前記戻し部近傍の前記配管内の水温または前記貯湯タンク内のあらかじめ定められた位置の水温を検知する温度検出手段と、この温度検出手段で検出された水温があらかじめ定められた温度になるように、前記流量調整手段を制御する制御手段と、を備えたものである。
【０００７】
【発明の実施の形態】
実施の形態１．
図１はこの発明に係る実施の形態１を示すヒートポンプシステムの構成を示す回路図、図２は貯湯タンクにおける高さ方向の水温分布変化の説明図、図３はＣＯ_２冷媒のヒートポンプの冷媒−水熱交換器入口水温とＣＯＰの関係を示す図である。
【０００８】
図１において、ヒートポンプ５０は、圧縮機５１、加熱熱交換器５２、絞り部５３及び吸熱熱交換器５４が順次接続されている。加熱循環回路６２は、貯湯タンク６０の底部、加熱ポンプ６１、ヒートポンプ５０の加熱熱交換器５２及び貯湯タンク６０の上部が順次接続されている。また、加熱循環回路６２には、ヒートポンプ５０にて加熱される温度を検知する沸き上げ水温センサー８４、貯湯タンク６０から加熱ポンプ６１に入水する入水温センサー８５が設けられている。負荷循環回路７０は、放熱熱交換器６７、負荷ポンプ７１及び負荷端末７２が順次接続されている。負荷端末７２は風呂の保温追焚機能、床暖房機能、放射空調機、強制対流空調機、風呂乾燥機、熱駆動冷凍機、熱駆動空調機、熱駆動除湿機、熱駆動加湿機等である。また、負荷循環回路７０の負荷端末７２には、負荷の温度を検出する負荷温度センサー８３が設けられている。
【０００９】
放熱循環回路６３は、貯湯タンク６０の上部の放熱循環回路取り出し部６４、負荷端末に接続された熱交換器６７、加熱ポンプ６５、主流量調整手段である流量調節弁６６及び貯湯タンク６０のあらかじめ定められた位置の戻し部６８が順次配管６９により接続されている。また、放熱循環回路６３には、貯湯タンク６０内のあらかじめ定められた位置の水温を検知する貯湯タンク水温センサーａ８１ａ、貯湯タンク６０の戻し部６８近傍の配管６９内の水温を検知する放熱戻し水温センサー８０が設けられている。
また、貯湯タンク水温センサーａ８１ａまたは放熱戻し水温センサー８０で検出された水温に基づいて、水温があらかじめ定められた温度になるように、流量調整弁６６制御する制御手段１０１が設けられている。
【００１０】
放熱循環回路６３には、負荷循環回路７０の他に、貯湯タンク６０の上部の放熱循環回路取り出し部６４近傍の配管６９の分岐部９８ａから分岐して給湯に使う出湯管９１が設けられ、出湯管９１には市水からの給水管９０が混合弁９２を介して接続される。
【００１１】
次に動作について図１〜３により説明する。上記構成のヒートポンプシステムにおいて、まず、貯湯タンク６０内に給水管９０より市水が流入し、貯湯タンク６０内、加熱循環回路６２内、放熱循環回路６３内は冷たい水で満たされる。この状態で、ヒートポンプ５０と加熱ポンプ６１を稼動させ、沸き上げ水温センサー８４の検出温度があらかじめ定められたの水温になるようにヒートポンプ５０と加熱ポンプ６１を調整すると貯湯タンク６０の上部より湧き上がってくる。貯湯タンク６０内に湯が満たされ、いわゆる満蓄状態になると入水温センサー８５の検出温度が上昇してあらかじめ定められたの温度になったところでヒートポンプ５０と加熱ポンプ６１を停止する。
【００１２】
この沸き上げ動作は通常、深夜電力時間帯や貯湯タンク６０内の貯湯量を検出してあらかじめ定められたの貯湯量より少ないときに実施する。一方、負荷端末７２の動作指示があったとき、負荷ポンプ７１が稼動して負荷循環回路７０内を熱媒体が循環し、放熱熱交換器６７で吸熱し負荷温度センサー８３の検出温度があらかじめ定められた温度になるまで送水される。これと同時に、放熱循環回路６３は放熱ポンプ６５が稼動し貯湯タンク６０の上部６４より湯を取り出し、放熱熱交換器６７で放熱し、放熱ポンプ６５、流量調整弁６６を通過し、戻し部６８より貯湯タンク６０内に戻る。
【００１３】
ここで、放熱循環回路６３からの戻り水が戻し部６８から戻った場合の貯湯タンク６０内の高さ方向の水温分布を図２により説明する。図において、実線が負荷を動作させる前、点線が負荷を動作させ貯湯タンク内に戻した場合の水温分布であり、実線のように沸き上げ後の水温分布は高温部と低温部が温度境界層を介して存在する。ここで貯湯タンク６０の戻し部６８が温度境界層より下の位置の場合は、図に示すように放熱循環回路６３からの戻り水が温度境界層より下の位置で、低温部の水温より高い温度で戻るので４０℃近傍の中温水が生成される。
【００１４】
一方、例えば、ＣＯ_２を冷媒に使用したヒートポンプサイクルの冬場における冷媒−水熱交換器（図１で言えば加熱熱交換器５２に相当）への入口水温とＣＯＰの関係を図３により説明すると、冷媒−水熱交換器入口水温が８℃のときのＣＯＰを１００％とすると入口水温が４５℃になるとＣＯＰが約６０％と大幅に低下してしまう。
従って、上述のように負荷端末７２が動作している状態で温度境界層より下で放熱循環回路６３からの水が戻り、貯湯タンク６０の低温部に４０℃前後の中温水が生成されたときは、これが沸き上げ時に加熱熱交換器５２に入水するとＣＯＰを大幅に低下させてしまうことになる。
【００１５】
本実施の形態では、貯湯タンク６０の戻し部６８が温度境界層より下の位置の場合でも、貯湯タンク６０の低温部に４０℃前後の中温水が生成されないようにし、ＣＯＰを大幅に低下させないように制御手段１０１で制御するものであり、次に説明する。
放熱循環回路６３からの戻り水の温度は、放熱循環回路６３の流量調整弁６６によって流量を変化させて任意の温度にすることが可能であるので、制御手段１０１により、放熱戻し水温センサー８０の検出温度があらかじめ定められた温度（低温）になるように、流量調整弁６６により戻り水の流量を変化させ、貯湯タンク６０の低温部に４０℃前後の中温水が生成されないように制御する。
なお、制御手段１０１により、放熱戻し水温センサー８０の検出温度（低温）が、戻し部６８での貯湯タンク水温センサーａ８１ａの検出温度と略同一になるように流量調整弁６６により戻り水の流量を制御してもよい。
また、貯湯タンク水温センサーａ８１ａの検出温度があらかじめ定められた温度（低温）になるように、流量調整弁６６により戻り水の流量を制御してもよい。
なお、貯湯タンク６０の戻し部６８が温度境界層より下の位置にするのは、負荷が大きく戻り温度が低い場合である。
【００１６】
以上のように、貯湯タンク６０及びこの貯湯タンク６０の水を加熱するヒートポンプ５０が接続された加熱循環回路６２と、貯湯タンク６０上部の放熱循環回路取り出し部６４、負荷端末７２に接続された放熱熱交換器６７、放熱ポンプ６５、流量量調弁６６及び貯湯タンク６０のあらかじめ定められた位置の戻し部６８が順次配管６９により接続された放熱循環回路６３と、この放熱循環回路６３の貯湯タンク６０の戻し部６８近傍の配管６９内の水温または貯湯タンク６０内のあらかじめ定められた位置の水温を検知する温度検出手段と、この温度検出手段で検出された水温があらかじめ定められた温度になるように、流量調整弁６６を制御する制御手段１０１とを備えたので、貯湯タンク６０内に中温水を生成することがなく、貯湯タンク内６０の温度成層を壊すことなく、温度境界層より下部の低温部は水温が低く、ＣＯ_２ヒートポンプの冷媒−水熱交換器に入水しても高いＣＯＰ運転をすることができる。
【００１７】
また、放熱循環回路６３の貯湯タンク６０の戻し部近傍の配管６９内の水温を検出する放熱戻し水温センサー８０と、貯湯タンク内のあらかじめ定められた位置の水温を検知する貯湯タンク水温センサーａ８１ａと、放熱戻し水温センサー８０により検出された水温が貯湯タンク水温センサーａ８１ａにより検出された水温とが略同一になるように制御する制御手段１０１と、を備えたので、温度境界層より下部の低温部は水温が低く、ＣＯ_２ヒートポンプの冷媒−水熱交換器に入水しても高いＣＯＰ運転をすることができる。
【００１８】
実施の形態２．
実施の形態１では、貯湯タンクの戻し部が温度境界層より下の位置の場合を示したが、本実施の形態は、貯湯タンクの戻し部を温度境界層より上にしたものである。構成は実施の形態１の図１で戻し部が異なるだけで他は同じなので、構成及び基本的な動作の説明を省略する。図４は実施の形態２を示すヒートポンプシステムの貯湯タンクにおける高さ方向の水温分布変化の説明図である。
【００１９】
放熱循環回路６３からの戻り水が戻し部６８から戻った場合の貯湯タンク６０内の高さ方向の水温分布を図４により説明する。図において実線が負荷を動作させる前、点線が負荷を動作させ貯湯タンク内に戻した場合の水温分布である。実線のように沸き上げ後の水温分布は高温部と低温部が温度境界層を介して存在する。
ここで、実施の形態１の図２のように温度境界層より下の位置で、低温部の水温より高い温度で戻してしまうと４０℃近傍の中温水が生成されてしまいＣＯＰが低下してしまう。
【００２０】
ここで、例えば、３７０Ｌの貯湯タンク６０で９０℃沸き上げとすると、一般的な家庭の給湯負荷から勘案して、貯湯タンクの半分程度を毎日使用する場合、温度境界層は貯湯タンクの中心部１８５Ｌ付近にできるのが上限で、そこより下の位置で、温度境界層が上下することになる。温度境界層より上の位置では９０℃の湯が存在し、温度境界層より下の位置で市水温度で水が存在することになる。
【００２１】
本実施の形態では、貯湯タンク６０の水の沸き上げ後で、負荷端末７２を使用開始前に貯湯タンク６０内にできる温度境界層より上方に、貯湯タンク６０の戻し部６８を配設したものである。例えば、上述のように３７０Ｌの貯湯タンク６０を使用し、温度境界層は貯湯タンクの中心部１８５Ｌ付近にできるのが上限のとき、放熱循環回路６３の戻し部６８を、例えば、貯湯タンク６０の上から１００Ｌの位置に配置する。
【００２２】
このような構成において、制御手段１０１により、図４に示す温度境界層より上の位置で、高温部の水温がそのまま給湯に使える温度、例えば５０℃以上になるように、流量調整弁６６で流量を調整し、放熱戻し水温センサー８０の検出温度、または、貯湯タンク水温センサー８１ａがあらかじめ定められた水温になるように制御する。
【００２３】
以上のように、貯湯タンク６０の水の沸き上げ後で、負荷端末７２を使用開始前に貯湯タンク６０内にできる温度境界層より上方に、貯湯タンク６０の戻し部６８を配設し、放熱戻し水温センサー８０の検出温度、または、貯湯タンク水温センサー８１ａがあらかじめ定められた水温になるように制御したので、温度境界層より上部の高温部はそのまま給湯可能であり、温度境界層より下部の低温部は水温が低く、ＣＯ_２ヒートポンプの冷媒−水熱交換器に入水しても高いＣＯＰ運転をすることができる。
【００２４】
実施の形態３．
図５はこの発明に係る実施の形態３を示すヒートポンプシステムの構成を示す回路図、図６は貯湯タンクにおける高さ方向の水温分布変化の説明図である。
図において実施の形態１の図１と同一の部分には同一の符号を付し説明を省略する。
図５において、貯湯タンク６０の上部の放熱循環回路取り出し部６４と、放熱循環回路６３の配管６９と出湯管９１の分岐部９８の間に開閉弁Ａ９３を配設し、出湯管９１に出湯水温センサー８６が取り付けられている。開閉弁Ａ９３は開閉手段であっても、流量調整手段であってもよい。
また、開閉弁Ａ９３の代わりに、分岐部９８に流量を任意に分配できる三方弁、または、切り替えの開閉手段を設けてもよい。
【００２５】
次に動作を図５、６により説明する。沸き上げ時は実施の形態１と同じであり、説明を省略する。放熱時は開閉弁Ａ９３が開の状態であり貯湯タンク６０から放熱循環回路６３へ循環する。出湯時には開閉弁Ａ９３が閉の状態で放熱循環回路６３の流量調整手段６６を開の状態で、放熱ポンプ６５は停止とすると、戻し部６８からタンク内湯が吸い込まれ放熱循環回路６３を逆流して、放熱循環回路取り出し部６４より出湯管９１に流入し出湯される。
【００２６】
放熱循環回路６３からの戻り水が戻し部６８から戻り、負荷端末７２の状況によりタンク内に中温水が生成してしまった場合の貯湯タンク６０内の高さ方向の水温分布を図６により説明する。図において、実線が出湯動作させる前の中温水が生成してしまった後の水温分布、点線が出湯動作させ貯湯タンク内より放熱循環回路６３を逆流させた水温分布である。
この状態で、貯湯タンク水温センサーａ８１ａの検出温度が出湯可能な、たとえば５０℃以上であれば、放熱循環回路６３を逆流させると、開閉弁Ａ９３が閉となっているので、取り出し位置（戻し部６８）より下の位置にある湯が入水され、出湯管９１より給湯される。このとき出湯管９１に設けられた出湯水温センサー８６の検出温度が所望の水温になるように混合弁９２の開度を調整してやればよい。また、タンク内の中温水の水温が低下して給湯不能な水温になった場合、開閉弁Ａ９３を開き、貯湯タンク６０上部の高温水を出湯させるようにする。
【００２７】
なお、５０℃以上の湯はそのまま出湯できるので、貯湯タンク６０上部の８０℃の湯より先に温度の低い部分を先に給湯すると、貯湯タンク６０下部より低い温度の市水が入水され、貯湯タンク６０下部を低い水温の水で満たすことができる。
【００２８】
このように、制御手段１０１は、放熱循環回路６３の放熱ポンプ６５を停止、流量調整弁６６を開とし、貯湯タンク水温センサー８１ａの検出温度があらかじめ定められた設定温度以上のときに、開閉弁Ａ９３をを閉とし、検出温度が設定温度未満のときに、開閉弁Ａ９３を開とする。
また、出湯水温センサー８６により検出された温度があらかじめ定められたの水温になるように混合弁９２または流量調整手段を制御する。
【００２９】
このようにして、仮に５０℃前後の中温水が生成されてしまったとしても放熱循環回路６３を逆流させて出湯させるので温度境界層より下部の低温部は水温が低い。
【００３０】
以上のように、放熱循環回路６３の放熱循環回路取り出し部６４近傍の配管６９から分岐して設けられた出湯管９１と、この出湯管９１及び配管６９の分岐部９８と放熱循環回路取り出し部６４の間に設けられた開閉弁Ａ９３または流量調節手段と、を備え、制御手段１０１は、放熱循環回路６３のポンプを停止、流量調整弁６６を開とし、貯湯タンク水温センサーａ８１ａの検出温度があらかじめ定められた設定温度以上のときに、開閉弁Ａ９３または流量調節手段を閉とし、検出温度が設定温度未満のときに、開閉弁Ａ９３または流量調節手段を開とするので、温度境界層より下部の低温部は水温が低く、ＣＯ_２ヒートポンプの冷媒−水熱交換器に入水しても高いＣＯＰ運転をすることができる。
【００３１】
また、出湯管９１に設けられ吸水管からの給水を混合する混合弁９２または給水と出湯の両方の流量調節が可能な流量調整手段と、この混合弁９２または流量調節手段の下流の出湯管９１の水温を検出する出湯水温センサー８６と、を備え、制御手段１０１は、出湯水温センサー８６により検出された温度があらかじめ定められたの水温になるように混合弁９２または流量調整手段を制御するので、所望の出湯温度にすることができる。
【００３２】
実施の形態４．
図７はこの発明に係る実施の形態４を示すヒートポンプシステムの構成を示す回路図、図８は貯湯タンクにおける高さ方向の水温分布変化の説明図である。
図において実施の形態１の図１と同一の部分には同一の符号を付し説明を省略する。
図７において、貯湯タンク６０の戻し部６８より上部に設けたバイパス管取り出し部９６より開閉弁Ｂ９５を介してバイパス管９４を放熱循環回路６３と並列に配設する。バイパス管９４の戻り側は、出湯管９１のバイパス管戻し分岐部９９に接続される。また、貯湯タンク６０上部の放熱循環回路取り出し部６４近傍の放熱循環回路６３の配管６９の分岐部９８と出湯管９１のバイパス管戻し分岐部９９の間に開閉弁９３が設けられる。なお、開閉Ａ弁９３は流量調節手段でもよい。
また、貯湯タンク水温センサーａ８１ａは戻し部６８の位置、貯湯タンク水温センサーｂ８１ｂはバイパス管９４のバイパス管取り出し部９６付近に配設する。
【００３３】
次に動作について図７、８により説明する。沸き上げ時は実施の形態１と同じであり説明を省略する。放熱時は貯湯タンク６０から循環回路６３へ湯が循環する。出湯時において、放熱が行われない場合には、開閉弁Ａ９３を開き、流量調整手段６６を開くと、貯湯タンク６０の上部からと戻し部６８からタンク内湯が吸い込まれ放熱循環回路６３を逆流して、タンク内上部湯と混合して出湯管９１から出湯される。しかし、負荷端末７２の動作と出湯が同じ時に起こる可能性があり、このときは、負荷端末の放熱と出湯を交互にやってもよいが、本実施の形態はこれを同時に行うものである。
【００３４】
すなわち、出湯時と放熱が同時に行われる場合には、開閉弁Ａ９３を閉、流量調整手段６６を開とし、放熱ポンプ６５を作動させ貯湯タンク６０から湯を放熱循環回路６３へ循環させ放熱を行う。同時に、バイパス管９４の開閉弁ｂ９５を開とすると、貯湯タンク６０のバイパス管取り出し部９６からタンク内の湯が吸い込まれ、バイパス管９４を通り出湯管９１から出湯される。
なお、中温水が貯湯タンク６０内広範囲に存在し、貯湯タンクの水温センサー８１ｂの検出温度が出湯可能な水温である場合にもこのようにバイパス管９４を使用する。
【００３５】
次に、放熱循環回路６３からの戻り水が戻し部６８から戻り、負荷端末７２の状況によりタンク内に中温水が生成してしまった場合の貯湯タンク６０内の高さ方向の水温分布を図により説明する。図において、実線が出湯動作させる前の中温水が生成してしまった後の水温分布、点線、１点鎖線が出湯動作させ貯湯タンク内よりバイパス管９３に流入させた水温分布である。
バイパス管９３に流入させるとバイパス管取り出し部９６より下の位置にある湯が入水され出湯管９１より給湯される。このとき水温センサー８１ｂの水温がそのまま出湯できるときは、放熱循環回路６３の逆流分のみを出湯させてやればよいし、できないときは、開閉弁Ａ９３を開き、貯湯タンク上部の湯と混合して出湯させる。そして、出湯管９１に配置された出湯水温センサー８４の検出温度が所望の水温になるように混合弁の開度を調整してやればよい。
【００３６】
このように、制御手段１０１は、放熱運転と出湯を同時に行うときは、開閉弁Ａ９３または流量調整手段を閉、放熱循環回路６３のポンプを作動、流量調整弁６６を開とするとともに、バイパス管９４近傍の貯湯タンク水温センサーｂ８１ｂの検出温度があらかじめ定められた温度以上のときに、バイパス管用の開閉弁９５または流量調整手段を開とし、検出温度が設定温度未満のときには開閉弁Ａ９３または流量調節手段を開とする。
また、出湯水温センサー８６により検出された温度があらかじめ定められたの水温になるように混合弁９２または流量調整手段を制御する。
【００３７】
以上のように、放熱循環回路６３の取り出し部近傍の配管から分岐して設けられた出湯管９１と、この出湯管９１から分岐し、バイパス管用の開閉弁９５または流量調整手段介して貯湯タンクの放熱回路の戻し部９６より上方に接続されたバイパス管９４と、出湯管９１と取り出し部近傍６４の配管６９の分岐部９８及びバイパス管９４と出湯管９１の分岐部の間に設けられた開閉弁Ａ９３または流量調節手段と、貯湯タンク６０内のバイパス管９４の接続部近傍の温度を検知するバイパス管近傍の貯湯タンク水温センサーｂ８１ｂと、を備え、制御手段１０１は、放熱運転と出湯を同時に行うときは、開閉弁Ａ９３または流量調整手段を閉、放熱循環回路６３のポンプを作動、流量調整弁６６を開とするとともに、バイパス管近傍の貯湯タンク水温センサーｂ８１ｂの検出温度があらかじめ定められた温度以上のときに、バイパス管用の開閉弁９５または流量調整手段を開とし、検出温度が設定温度未満のときには、開閉弁Ａ９３または流量調節手段を開とするので、貯湯タンク６０の高さ方向に多く中温水が存在するときに、放熱、出湯を効率よく行うことができる。
また、放熱しながら中温水を出湯させることができる。
【００３８】
実施の形態５．
図９はこの発明に係る実施の形態５を示すヒートポンプシステムの構成を示す回路図である。図において実施の形態１の図１及び羽実施の形態３の図５と同一の部分には同一の符号を付し説明を省略する。
貯湯タンクの戻し部６８を貯湯タンク６０の上部に設け、この戻し部６８から貯湯タンク６０内部に延設され、戻し口９７ａを有する貯湯タンク内戻し配管９７を設けている。貯湯タンク内戻し配管９７は熱伝導性のよい材質、例えば、銅等を使用する。
【００３９】
次に動作について説明する。沸き上げ時は実施の形態１と同じであり説明を主略する。放熱時は貯湯タンク６０から循環回路６３へ湯が循環する。貯湯タンク内戻し配管９７により、周囲の湯と熱交換して、戻し口９７ａより貯湯タンク６０内に戻る。放熱戻し水温センサー８０の検出温度が低い場合、そのまま貯湯タンク水温センサー８１ａの位置に戻すと、多量の中温水、およそ４０℃前後を生成してしまう。
本実施の形態では、戻し口９７ａまでの貯湯タンク内戻し配管９７により、周囲の湯と熱交換することにより中温水の温度を上げ、たとえば５０℃以上でそのまま出湯可能な湯を生成できる。
【００４０】
以上のように、貯湯タンクの戻し部を貯湯タンクの上部に設け、この戻し部から貯湯タンク内部に延設された貯湯内戻し配管を備えたので、貯湯タンク内戻し配管９７により、周囲の湯と熱交換して、中温水の水温をそのまま出湯できる水温まで上昇させることができる。
【００４１】
なお、実施の形態１〜５において、ヒートポンプの冷媒はＣＯ_２として、冷媒−水熱交換器の入水温度を低く保つようにし、高いＣＯＰ運転をするようにすることができる。
【００４２】
【発明の効果】
以上のように、貯湯タンク及びこの貯湯タンクの水を加熱するヒートポンプが接続された加熱循環回路と、前記貯湯タンク上部の取り出し部、負荷端末に接続された熱交換器、ポンプ、主流量調整手段及び前記貯湯タンクのあらかじめ定められた位置の戻し部が順次配管により接続された放熱循環回路と、この放熱循環回路の前記貯湯タンクの前記戻し部近傍の前記配管内の水温または前記貯湯タンク内のあらかじめ定められた位置の水温を検知する温度検出手段と、この温度検出手段で検出された水温があらかじめ定められた温度になるように、前記流量調整手段を制御する制御手段と、を備えたので、簡単な構成で、効率を高くすることができる。
【図面の簡単な説明】
【図１】この発明の実施の形態１を示すヒートポンプシステムの構成を示す回路図である。
【図２】貯湯タンク高さ方向の水温分布変化の説明図である。
【図３】ＣＯ_２冷媒のヒートポンプの冷媒−水熱交換器入口水温とＣＯＰの関係を示す図である。
【図４】実施の形態２を示すヒートポンプシステムの貯湯タンクにおける高さ方向の水温分布変化の説明図である。
【図５】この発明に係る実施の形態３を示すヒートポンプシステムの構成を示す回路図である。
【図６】この発明に係る実施の形態３を示すヒートポンプシステムの貯湯タンク高さ方向の水温分布変化の説明図である。
【図７】この発明の実施の形態４を示すヒートポンプシステムの構成を示す回路図である。
【図８】この発明に係る実施の形態４を示すヒートポンプシステムの貯湯タンク高さ方向の水温分布変化の説明図である。
【図９】この発明の実施の形態５を示すヒートポンプシステムの構成を示す回路図である。
【符号の説明】
１　ヒートポンプ、５１　圧縮機、５２　加熱熱交換器、５３　絞り部、５４吸熱熱交換器、６０　貯湯タンク、６１　加熱ポンプ、６２　加熱循環回路、６３　放熱循環回路、６４　放熱循環回路取り出し部、６５　放熱ポンプ、６６流量調整弁、６７　放熱熱交換器、６８　放熱循環回路戻し部、６９　配管、７０　負荷循環回路、７１　負荷ポンプ、７２　負荷端末、８０　放熱戻し水温センサ、８１ａ　貯湯タンク水温センサーａ、８１ｂ　貯湯タンク水温センサーｂ、８３　負荷温度センサー、８４　沸き上げ温度センサー、８５　入水温度センサー、９０　給水管、９１　出湯管、９２　混合弁、９３　開閉弁Ａ、９４　バイパス管、９５　開閉弁Ｂ、９６　バイパス管取り出し部、９７　貯湯タンク内戻し配管、９８　分岐部、９９　バイパス管戻し分岐部、１０１　制御手段。[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump system in which a heat pump heat source boils water from an upper portion of a hot water storage tank and can control the amount of hot water and the temperature of the hot water, and a load terminal such as additional heating of a bath or heating.
[0002]
[Prior art]
A hot water storage tank, a compressor, a heat transfer tube for the refrigerant in which the refrigerant from the compressor circulates, a heat transfer tube for the hot water in which the water from the hot water tank circulates, and a supplementary heat transfer tube in which the hot water of the bathtub circulates. A heat pump water heater is constituted by the formed radiator, the expansion valve, and an evaporator for exchanging heat between the refrigerant from the expansion valve and the outside air, and the refrigerant from the compressor passes through the refrigerant heat transfer tube. By circulating, the water circulating from the hot water storage tank to the hot water storage heat transfer tube is heated, and the heated water is returned to the hot water storage tank to store the hot water, and the hot water of the bathtub is circulated through the additional heating heat transfer tube. Then, additional heating of the bath is performed by heating with a refrigerant (for example, Patent Document 1).
[0003]
[Patent Document 1]
JP-A-2002-106963 (paragraphs 0020-0027, 0053-0059, FIG. 1)
[0004]
[Problems to be solved by the invention]
Conventional heat pump system, the reheating circuit can only operate only in the heat exchange with the refrigerant, it can not reheat when the reheating load occurs in the time zone other than late-night power time in the hot water storage water heater, In addition, there is a problem that even when the heat pump enters a defrost operation, it becomes impossible to reheat the heat pump. Further, since the heat exchangers for hot water supply, additional heating, and refrigerant are the same, there are three types of operation: hot water supply only, additional heating only, and simultaneous hot water supply additional heating. ₂ In the case of a heat pump using a refrigerant, the efficiency cannot be improved unless the temperature of the water flowing into the heat exchanger is low. Therefore, there is a problem that the efficiency is reduced when a high water temperature from the reheating flows into the heat exchanger.
[0005]
The present invention has been made to solve the above problems, and has as its object to provide a highly efficient heat pump system with a simple configuration.
[0006]
[Means for Solving the Problems]
A heat pump system according to the present invention includes a heating circulation circuit to which a hot water storage tank and a heat pump that heats water in the hot water storage tank are connected; a heat exchanger connected to a load terminal at an upper portion of the hot water storage tank; a load terminal; A flow circulating circuit in which a flow rate adjusting means and a return portion of a predetermined position of the hot water storage tank are sequentially connected by piping, and a water temperature or the hot water storage in the pipe near the return portion of the hot water storage tank of the heat radiation circulation circuit. Temperature detecting means for detecting a water temperature at a predetermined position in the tank, and control means for controlling the flow rate adjusting means so that the water temperature detected by the temperature detecting means becomes a predetermined temperature. It is provided.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiment 1 FIG.
FIG. 1 is a circuit diagram showing a configuration of a heat pump system according to a first embodiment of the present invention, FIG. 2 is an explanatory diagram of a change in water temperature distribution in a height direction in a hot water storage tank, and FIG. ₂ It is a figure which shows the relationship between COP and the refrigerant-water heat exchanger inlet water temperature of the heat pump of a refrigerant.
[0008]
In FIG. 1, a heat pump 50 includes a compressor 51, a heating heat exchanger 52, a throttle unit 53, and an endothermic heat exchanger 54 which are sequentially connected. In the heating circulation circuit 62, the bottom of the hot water storage tank 60, the heating pump 61, the heating heat exchanger 52 of the heat pump 50, and the upper part of the hot water storage tank 60 are sequentially connected. Further, the heating circulation circuit 62 is provided with a boiling water temperature sensor 84 for detecting the temperature heated by the heat pump 50 and an incoming water temperature sensor 85 for entering the heating pump 61 from the hot water storage tank 60. In the load circulation circuit 70, a heat radiation heat exchanger 67, a load pump 71, and a load terminal 72 are sequentially connected. The load terminal 72 is a heat retention / heating function for the bath, a floor heating function, a radiant air conditioner, a forced convection air conditioner, a bath dryer, a heat drive refrigerator, a heat drive air conditioner, a heat drive dehumidifier, a heat drive humidifier, and the like. . The load terminal 72 of the load circulation circuit 70 is provided with a load temperature sensor 83 for detecting the temperature of the load.
[0009]
The heat radiation circulation circuit 63 includes a heat radiation circulation circuit take-out portion 64 at the upper part of the hot water storage tank 60, a heat exchanger 67 connected to a load terminal, a heating pump 65, a flow control valve 66 serving as a main flow rate adjusting means, and a hot water storage tank 60. Return portions 68 at predetermined positions are sequentially connected by piping 69. Further, the heat radiation circulation circuit 63 includes a hot water tank temperature sensor a81a for detecting a water temperature at a predetermined position in the hot water tank 60, and a heat return water temperature for detecting a water temperature in a pipe 69 near the return portion 68 of the hot water tank 60. A sensor 80 is provided.
Further, control means 101 is provided for controlling the flow rate adjusting valve 66 based on the water temperature detected by the hot water storage tank water temperature sensor a81a or the heat radiation return water temperature sensor 80 so that the water temperature becomes a predetermined temperature.
[0010]
In addition to the load circulation circuit 70, the heat radiation circulation circuit 63 is provided with a tapping pipe 91 which branches off from a branch 98 a of the pipe 69 near the heat radiation circulation circuit take-out part 64 above the hot water storage tank 60 and is used for hot water supply. A water supply pipe 90 from city water is connected to the pipe 91 via a mixing valve 92.
[0011]
Next, the operation will be described with reference to FIGS. In the heat pump system configured as described above, first, city water flows into the hot water storage tank 60 from the water supply pipe 90, and the inside of the hot water storage tank 60, the inside of the heating circulation circuit 62, and the inside of the heat radiation circulation circuit 63 are filled with cold water. In this state, the heat pump 50 and the heating pump 61 are operated, and the heat pump 50 and the heating pump 61 are adjusted so that the temperature detected by the boiling water temperature sensor 84 becomes a predetermined water temperature. Come. When the hot water storage tank 60 is filled with hot water, that is, in a so-called full storage state, when the temperature detected by the incoming water temperature sensor 85 increases and reaches a predetermined temperature, the heat pump 50 and the heating pump 61 are stopped.
[0012]
This boiling operation is usually performed when the amount of hot water stored in the hot water storage tank 60 is less than a predetermined amount by detecting the amount of hot water stored in the midnight power time zone or the hot water storage tank 60. On the other hand, when there is an operation instruction of the load terminal 72, the load pump 71 operates, the heat medium circulates in the load circulation circuit 70, absorbs heat in the heat radiation heat exchanger 67, and the temperature detected by the load temperature sensor 83 is determined in advance. Water is sent until the temperature reaches the specified level. At the same time, the heat radiating pump 65 is operated to take out hot water from the upper portion 64 of the hot water storage tank 60, radiate heat in the heat radiating heat exchanger 67, pass through the heat radiating pump 65, the flow regulating valve 66, and return to the return portion 68. It returns to the inside of hot water storage tank 60.
[0013]
Here, the water temperature distribution in the height direction in the hot water storage tank 60 when the return water from the heat radiation circulation circuit 63 returns from the return section 68 will be described with reference to FIG. In the figure, the solid line is the water temperature distribution when the load is operated and returned into the hot water storage tank before the load is operated, and the water temperature distribution after boiling as shown by the solid line is the temperature boundary layer between the high temperature part and the low temperature part. Exists through. Here, when the return portion 68 of the hot water storage tank 60 is located below the temperature boundary layer, as shown in the figure, the return water from the heat radiation circulation circuit 63 is located below the temperature boundary layer and higher than the water temperature of the low temperature portion. Since the temperature returns, medium-temperature water near 40 ° C. is generated.
[0014]
On the other hand, for example, CO ₂ The relationship between the inlet water temperature to the refrigerant-water heat exchanger (corresponding to the heating heat exchanger 52 in FIG. 1) and the COP in the winter season of the heat pump cycle using the refrigerant as the refrigerant will be described with reference to FIG. Assuming that the COP when the water temperature at the vessel inlet is 8 ° C. is 100%, the COP at the inlet water temperature becomes 45 ° C. is significantly reduced to about 60%.
Therefore, when the water from the heat radiation circulation circuit 63 returns below the temperature boundary layer while the load terminal 72 is operating as described above, and medium-temperature water around 40 ° C. is generated in the low-temperature portion of the hot water storage tank 60, When the water enters the heating heat exchanger 52 at the time of boiling, the COP is greatly reduced.
[0015]
In the present embodiment, even when the return portion 68 of the hot water storage tank 60 is located below the temperature boundary layer, medium-temperature water around 40 ° C. is not generated in the low-temperature portion of the hot water storage tank 60, and the COP is not significantly reduced. The control is performed by the control means 101 as described above.
The temperature of the return water from the heat radiation circulation circuit 63 can be set to an arbitrary temperature by changing the flow rate by the flow control valve 66 of the heat radiation circulation circuit 63. The flow rate of the return water is changed by the flow rate adjusting valve 66 so that the detected temperature becomes a predetermined temperature (low temperature), and control is performed so that medium-temperature water around 40 ° C. is not generated in the low-temperature portion of the hot water storage tank 60.
The flow rate of the return water is controlled by the flow control valve 66 by the control means 101 such that the detected temperature (low temperature) of the heat release return water temperature sensor 80 is substantially the same as the detected temperature of the hot water storage tank water temperature sensor a81a in the return section 68. It may be controlled.
Further, the flow rate of the return water may be controlled by the flow rate adjusting valve 66 such that the temperature detected by the hot water tank water temperature sensor a81a becomes a predetermined temperature (low temperature).
The return portion 68 of the hot water storage tank 60 is located below the temperature boundary layer when the load is large and the return temperature is low.
[0016]
As described above, the heating circulation circuit 62 to which the hot water storage tank 60 and the heat pump 50 for heating the water in the hot water storage tank 60 are connected, the heat radiation circulation circuit take-out portion 64 above the hot water storage tank 60, and the heat radiation connected to the load terminal 72. A heat exchanger 67, a heat radiation pump 65, a flow rate regulating valve 66, and a heat radiation circulation circuit 63 in which return portions 68 at predetermined positions of a hot water storage tank 60 are sequentially connected by a pipe 69, and a hot water storage tank of the heat radiation circulation circuit 63 A temperature detecting means for detecting the water temperature in the pipe 69 near the return portion 68 of the pipe 60 or the water temperature at a predetermined position in the hot water storage tank 60; and the water temperature detected by the temperature detecting means becomes a predetermined temperature. As described above, the control means 101 for controlling the flow rate regulating valve 66 is provided, so that the medium-temperature water is not generated in the hot water storage tank 60, Without breaking the thermal stratification of the click 60, the low temperature portion of the lower than the temperature boundary layer temperature is low, CO ₂ Even if water enters the refrigerant-water heat exchanger of the heat pump, a high COP operation can be performed.
[0017]
Further, a heat return water temperature sensor 80 for detecting a water temperature in a pipe 69 near a return portion of the hot water tank 60 of the heat radiation circulation circuit 63, and a hot water tank temperature sensor a81a for detecting a water temperature at a predetermined position in the hot water tank. And control means 101 for controlling the water temperature detected by the heat release return water temperature sensor 80 to be substantially the same as the water temperature detected by the hot water storage tank water temperature sensor a81a. Means that the water temperature is low and CO ₂ Even if water enters the refrigerant-water heat exchanger of the heat pump, a high COP operation can be performed.
[0018]
Embodiment 2 FIG.
In the first embodiment, the case where the return portion of the hot water storage tank is at a position below the temperature boundary layer has been described, but in the present embodiment, the return portion of the hot water storage tank is located above the temperature boundary layer. The configuration is the same as that of the first embodiment shown in FIG. FIG. 4 is an explanatory diagram of a change in water temperature distribution in a height direction in a hot water storage tank of the heat pump system according to the second embodiment.
[0019]
The water temperature distribution in the height direction in the hot water storage tank 60 when the return water from the heat radiation circulation circuit 63 returns from the return section 68 will be described with reference to FIG. In the figure, the solid line shows the water temperature distribution when the load is operated and the dotted line shows the water temperature distribution when the load is operated and returned into the hot water storage tank. As shown by the solid line, the water temperature distribution after boiling includes a high-temperature portion and a low-temperature portion via the temperature boundary layer.
Here, as shown in FIG. 2 of the first embodiment, if the temperature is returned to a position lower than the temperature boundary layer at a temperature higher than the water temperature of the low temperature part, medium-temperature water near 40 ° C. is generated, and the COP decreases. I will.
[0020]
Here, for example, assuming that the water is heated to 90 ° C. in the 370 L hot water storage tank 60, when about half of the hot water storage tank is used every day in consideration of a general household hot water supply load, the temperature boundary layer is located at the center of the hot water storage tank. The upper limit is around 185 L, and the temperature boundary layer goes up and down below that. 90 ° C. hot water exists at a position above the temperature boundary layer, and water exists at a city water temperature at a position below the temperature boundary layer.
[0021]
In the present embodiment, the return portion 68 of the hot water storage tank 60 is disposed above a temperature boundary layer formed in the hot water storage tank 60 before the use of the load terminal 72 after the boiling of the water in the hot water storage tank 60. It is. For example, when the hot water storage tank 60 of 370 L is used as described above, and the temperature boundary layer can be formed near the center 185 L of the hot water storage tank at the upper limit, the return portion 68 of the heat radiation circulation circuit 63 is replaced with the hot water storage tank 60, for example. Place at 100L from above.
[0022]
In such a configuration, the flow rate is controlled by the flow control valve 66 by the control means 101 so that the water temperature in the high-temperature portion becomes higher than the temperature usable for hot water supply, for example, 50 ° C. or higher, at a position above the temperature boundary layer shown in FIG. Is adjusted so that the detected temperature of the heat release return water temperature sensor 80 or the hot water storage tank water temperature sensor 81a becomes a predetermined water temperature.
[0023]
As described above, after the water in the hot water storage tank 60 has been boiled, the return portion 68 of the hot water storage tank 60 is disposed above the temperature boundary layer formed in the hot water storage tank 60 before the load terminal 72 is used. Since the detection temperature of the return water temperature sensor 80 or the hot water storage tank water temperature sensor 81a is controlled to be a predetermined water temperature, the high temperature part above the temperature boundary layer can be supplied as it is, and the high temperature part below the temperature boundary layer can be supplied. The water temperature is low in the low temperature part, and CO ₂ Even if water enters the refrigerant-water heat exchanger of the heat pump, a high COP operation can be performed.
[0024]
Embodiment 3 FIG.
FIG. 5 is a circuit diagram showing a configuration of a heat pump system according to Embodiment 3 of the present invention, and FIG. 6 is an explanatory diagram of a change in water temperature distribution in a height direction in a hot water storage tank.
In the figure, the same parts as those in FIG. 1 of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.
In FIG. 5, an opening / closing valve A93 is provided between a heat radiation circulation circuit take-out part 64 at the upper part of the hot water storage tank 60 and a pipe 69 of the heat radiation circulation circuit 63 and a branch part 98 of the water discharge pipe 91. A sensor 86 is attached. The opening / closing valve A93 may be an opening / closing means or a flow rate adjusting means.
Instead of the on-off valve A93, a three-way valve capable of arbitrarily distributing the flow rate to the branch portion 98 or a switching on-off means may be provided.
[0025]
Next, the operation will be described with reference to FIGS. The operation at the time of boiling is the same as that of the first embodiment, and the description is omitted. During heat release, the on-off valve A93 is open and circulates from the hot water storage tank 60 to the heat release circuit 63. When the hot water is discharged, when the heat radiation pump 65 is stopped with the on-off valve A93 closed and the flow rate adjusting means 66 of the heat radiation circulation circuit 63 opened, the hot water in the tank is sucked from the return portion 68 and the heat radiation circulation circuit 63 flows backward. Then, the heat flows into the tapping pipe 91 from the heat radiation circulation circuit take-out section 64 and is discharged.
[0026]
FIG. 6 illustrates the water temperature distribution in the height direction in the hot water storage tank 60 when the return water from the heat radiation circulation circuit 63 returns from the return unit 68 and medium-temperature water is generated in the tank depending on the state of the load terminal 72. I do. In the figure, the solid line indicates the water temperature distribution after the medium-temperature water has been generated before the hot water supply operation, and the dotted line indicates the water temperature distribution when the hot water storage operation is performed and the heat radiation circulation circuit 63 flows backward from the hot water storage tank.
In this state, if the temperature detected by the hot water storage tank water temperature sensor a81a is such that the hot water can be discharged, for example, 50 ° C. or more, when the heat radiation circulation circuit 63 is reversed, the on-off valve A93 is closed. 68) Hot water at a lower position is supplied and supplied from the tapping pipe 91. At this time, the opening of the mixing valve 92 may be adjusted so that the detection temperature of the tap water temperature sensor 86 provided in the tap water pipe 91 becomes a desired water temperature. In addition, when the temperature of the medium-temperature water in the tank drops and becomes a water temperature at which hot water cannot be supplied, the on-off valve A93 is opened so that the high-temperature water in the upper part of the hot water storage tank 60 is discharged.
[0027]
Since the hot water of 50 ° C. or more can be discharged as it is, if the lower temperature portion is supplied first before the hot water of 80 ° C. at the upper part of the hot water storage tank 60, city water at a lower temperature than the lower part of the hot water storage tank 60 is supplied. The lower part of the tank 60 can be filled with low-temperature water.
[0028]
As described above, the control means 101 stops the heat radiation pump 65 of the heat radiation circulation circuit 63, opens the flow control valve 66, and, when the detected temperature of the hot water storage tank water temperature sensor 81a is equal to or higher than a predetermined set temperature, the opening / closing valve A93 is closed, and when the detected temperature is lower than the set temperature, the on-off valve A93 is opened.
Further, the mixing valve 92 or the flow rate adjusting means is controlled so that the temperature detected by the tap water temperature sensor 86 becomes a predetermined water temperature.
[0029]
In this way, even if medium-temperature water of about 50 ° C. is generated, since the heat is circulated by flowing back the heat radiation circulation circuit 63, the temperature of the low-temperature portion below the temperature boundary layer is low.
[0030]
As described above, the tapping pipe 91 branching off from the pipe 69 near the heat dissipation circuit take-out section 64 of the heat dissipation circuit 63, the branch section 98 of the tapping pipe 91 and the pipe 69, and the heat dissipation circuit take-out section 64 The control means 101 stops the pump of the heat radiation circulation circuit 63, opens the flow control valve 66, and detects the temperature of the hot water storage tank water temperature sensor a81a in advance. When the temperature is equal to or higher than the set temperature, the on-off valve A93 or the flow rate adjusting means is closed, and when the detected temperature is lower than the set temperature, the on-off valve A93 or the flow rate adjusting means is opened. The water temperature is low in the low temperature part, and CO ₂ Even if water enters the refrigerant-water heat exchanger of the heat pump, a high COP operation can be performed.
[0031]
Also, a mixing valve 92 provided in the tapping pipe 91 for mixing water supplied from the water suction pipe or a flow rate adjusting means capable of adjusting the flow rates of both water supply and tapping water, and a tapping pipe 91 downstream of the mixing valve 92 or the flow rate adjusting means. And a control unit 101 controls the mixing valve 92 or the flow rate adjusting unit so that the temperature detected by the tap water temperature sensor 86 becomes a predetermined water temperature. The desired tapping temperature can be obtained.
[0032]
Embodiment 4 FIG.
FIG. 7 is a circuit diagram showing a configuration of a heat pump system according to Embodiment 4 of the present invention, and FIG. 8 is an explanatory diagram of a change in water temperature distribution in a height direction in a hot water storage tank.
In the figure, the same parts as those in FIG. 1 of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.
In FIG. 7, a bypass pipe 94 is disposed in parallel with a heat radiating circuit 63 via an on-off valve B95 from a bypass pipe outlet 96 provided above the return section 68 of the hot water storage tank 60. The return side of the bypass pipe 94 is connected to the bypass pipe return branching section 99 of the tapping pipe 91. An on-off valve 93 is provided between a branch 98 of the pipe 69 of the heat radiation circuit 63 and a bypass pipe return branch 99 of the tapping pipe 91 near the heat radiation circuit take-out part 64 above the hot water storage tank 60. Note that the opening / closing A valve 93 may be a flow rate adjusting means.
The hot water tank temperature sensor a81a is disposed at the position of the return portion 68, and the hot water tank temperature sensor b81b is disposed near the bypass pipe take-out portion 96 of the bypass pipe 94.
[0033]
Next, the operation will be described with reference to FIGS. The operation at the time of boiling is the same as that of the first embodiment, and the description is omitted. During heat release, hot water circulates from hot water storage tank 60 to circulation circuit 63. When the heat is not dissipated at the time of tapping, when the on-off valve A93 is opened and the flow rate adjusting means 66 is opened, the hot water in the tank is sucked in from the upper part of the hot water storage tank 60 and from the return part 68, and flows back through the heat radiation circulation circuit 63. Then, the hot water is mixed with the hot water in the tank and discharged from the hot water pipe 91. However, there is a possibility that the operation of the load terminal 72 and the tapping may occur at the same time. In this case, the heat radiation of the load terminal and the tapping may be alternately performed, but in the present embodiment, this is performed simultaneously.
[0034]
That is, when the hot water is discharged and the heat radiation is performed simultaneously, the on-off valve A93 is closed, the flow rate adjusting means 66 is opened, and the heat radiation pump 65 is operated to circulate the hot water from the hot water storage tank 60 to the heat radiation circulation circuit 63 to dissipate heat. . At the same time, when the on-off valve b95 of the bypass pipe 94 is opened, the hot water in the tank is sucked from the bypass pipe outlet 96 of the hot water storage tank 60, and the hot water is discharged from the tapping pipe 91 through the bypass pipe 94.
It should be noted that the bypass pipe 94 is also used when the medium-temperature water is present in a wide area in the hot water storage tank 60 and the temperature detected by the water temperature sensor 81b of the hot water storage tank is a water temperature at which hot water can be discharged.
[0035]
Next, the water temperature distribution in the height direction in the hot water storage tank 60 when the return water from the heat radiation circulation circuit 63 returns from the return unit 68 and medium-temperature water is generated in the tank depending on the state of the load terminal 72 is shown. This will be described below. In the figure, the solid line is the water temperature distribution after the medium-temperature water has been generated before the hot-water tapping operation, and the dotted line and the dashed-dotted line are the water temperature distributions from the hot-water storage tank into the bypass pipe 93 after the hot water tapping operation.
When the hot water flows into the bypass pipe 93, the hot water at a position below the bypass pipe take-out portion 96 is supplied and supplied from the hot water discharge pipe 91. At this time, if the water temperature of the water temperature sensor 81b can be supplied as it is, only the reverse flow of the heat radiating circuit 63 may be supplied. If not, the on-off valve A93 is opened and mixed with the hot water above the hot water storage tank. Let the water out. Then, the opening of the mixing valve may be adjusted so that the detection temperature of the tap water temperature sensor 84 disposed in the tap pipe 91 becomes a desired water temperature.
[0036]
As described above, the control means 101 closes the on-off valve A93 or the flow rate adjustment means, activates the pump of the heat radiation circulation circuit 63, opens the flow rate adjustment valve 66, and opens the bypass pipe when performing the heat radiation operation and tapping at the same time. When the detected temperature of the hot water storage tank water temperature sensor b81b near 94 is equal to or higher than a predetermined temperature, the on-off valve 95 or the flow rate adjusting means for the bypass pipe is opened, and when the detected temperature is lower than the set temperature, the on-off valve A93 or the flow rate adjusting means. Open the means.
Further, the mixing valve 92 or the flow rate adjusting means is controlled so that the temperature detected by the tap water temperature sensor 86 becomes a predetermined water temperature.
[0037]
As described above, the tapping pipe 91 provided branching from the pipe near the take-out portion of the heat radiation circulation circuit 63, and the tapping pipe 95 branched from the tapping pipe 91 and the hot water storage tank via the on-off valve 95 for the bypass pipe or the flow rate adjusting means. A bypass pipe 94 connected above the return portion 96 of the heat dissipation circuit, a branch 98 of the tapping pipe 91 and the pipe 69 near the take-out section 64, and an opening / closing provided between the bypass pipe 94 and the branch of the tapping pipe 91. The control unit 101 includes a valve A93 or a flow rate adjusting means, and a hot water tank water temperature sensor b81b near the bypass pipe for detecting a temperature near a connection portion of the bypass pipe 94 in the hot water storage tank 60. When performing the operation, the on / off valve A93 or the flow rate adjusting means is closed, the pump of the heat radiation circulation circuit 63 is operated, the flow rate adjusting valve 66 is opened, and the hot water tank near the bypass pipe is opened. When the temperature detected by the cooling water temperature sensor b81b is equal to or higher than a predetermined temperature, the on-off valve 95 or the flow rate adjusting means for the bypass pipe is opened. Therefore, when a large amount of medium-temperature water exists in the height direction of the hot water storage tank 60, heat radiation and tapping can be efficiently performed.
Also, the medium-temperature water can be discharged while dissipating heat.
[0038]
Embodiment 5 FIG.
FIG. 9 is a circuit diagram showing a configuration of a heat pump system according to Embodiment 5 of the present invention. In the drawing, the same portions as those in FIG. 1 of the first embodiment and FIG. 5 of the wing embodiment 3 are denoted by the same reference numerals, and description thereof will be omitted.
A return portion 68 of the hot water storage tank is provided above the hot water storage tank 60, and a return pipe 97 inside the hot water storage tank that extends from the return portion 68 into the hot water storage tank 60 and has a return port 97 a is provided. The hot water storage tank return pipe 97 uses a material having good heat conductivity, for example, copper or the like.
[0039]
Next, the operation will be described. The operation at the time of boiling is the same as that of the first embodiment, and the description is omitted. During heat release, hot water circulates from hot water storage tank 60 to circulation circuit 63. Heat is exchanged with the surrounding hot water by the return pipe 97 inside the hot water storage tank, and returns to the hot water storage tank 60 through the return port 97a. When the detected temperature of the heat release return water temperature sensor 80 is low, if the temperature is returned to the position of the hot water storage tank water temperature sensor 81a as it is, a large amount of medium-temperature water, about 40 ° C., will be generated.
In the present embodiment, the temperature of the medium-temperature water is increased by exchanging heat with the surrounding hot water through the return pipe 97 in the hot water storage tank to the return port 97a, so that hot water that can be directly discharged at 50 ° C. or more can be generated.
[0040]
As described above, the return portion of the hot water storage tank is provided above the hot water storage tank, and the return pipe for hot water storage extending from the return portion to the inside of the hot water storage tank is provided. And the temperature of the medium-temperature water can be raised to the temperature at which hot water can be discharged.
[0041]
In the first to fifth embodiments, the refrigerant of the heat pump is CO 2 ₂ As a result, the inlet water temperature of the refrigerant-water heat exchanger can be kept low, and a high COP operation can be performed.
[0042]
【The invention's effect】
As described above, the heating circulation circuit to which the hot water storage tank and the heat pump that heats the water in the hot water storage tank are connected, the heat exchanger, the pump, and the main flow rate adjusting means connected to the take-out part at the top of the hot water storage tank, the load terminal. And a heat radiating circuit in which a return portion of a predetermined position of the hot water storage tank is sequentially connected by a pipe, and a water temperature in the pipe near the return portion of the hot water storage tank of the heat radiation circulating circuit or in the hot water storage tank. Since it has temperature detecting means for detecting a water temperature at a predetermined position, and control means for controlling the flow rate adjusting means so that the water temperature detected by the temperature detecting means becomes a predetermined temperature. With a simple configuration, the efficiency can be increased.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing a configuration of a heat pump system according to a first embodiment of the present invention.
FIG. 2 is an explanatory diagram of a change in water temperature distribution in a hot water storage tank height direction.
FIG. 3 CO ₂ It is a figure which shows the relationship between COP and the refrigerant-water heat exchanger inlet water temperature of the heat pump of a refrigerant.
FIG. 4 is an explanatory diagram of a water temperature distribution change in a height direction in a hot water storage tank of a heat pump system according to a second embodiment.
FIG. 5 is a circuit diagram showing a configuration of a heat pump system according to a third embodiment of the present invention.
FIG. 6 is an explanatory diagram of a change in water temperature distribution in a height direction of a hot water storage tank of the heat pump system according to the third embodiment of the present invention.
FIG. 7 is a circuit diagram showing a configuration of a heat pump system according to a fourth embodiment of the present invention.
FIG. 8 is an explanatory diagram of a change in water temperature distribution in a hot water storage tank height direction of a heat pump system according to a fourth embodiment of the present invention.
FIG. 9 is a circuit diagram showing a configuration of a heat pump system according to Embodiment 5 of the present invention.
[Explanation of symbols]
Reference Signs List 1 heat pump, 51 compressor, 52 heating heat exchanger, 53 throttle unit, 54 heat absorption heat exchanger, 60 hot water storage tank, 61 heating pump, 62 heating circulation circuit, 63 heat radiation circulation circuit, 64 heat radiation circulation circuit take-out part, 65 heat radiation Pump, 66 flow regulating valve, 67 heat radiation heat exchanger, 68 heat radiation circulation circuit return part, 69 piping, 70 load circulation circuit, 71 load pump, 72 load terminal, 80 heat radiation return water temperature sensor, 81a hot water storage tank water temperature sensor a, 81b Hot water storage tank temperature sensor b, 83 load temperature sensor, 84 boiling temperature sensor, 85 incoming water temperature sensor, 90 water supply pipe, 91 hot water pipe, 92 mixing valve, 93 on-off valve A, 94 bypass pipe, 95 on-off valve B, 96 bypass Pipe take-out section, 97 return pipe in hot water storage tank, 98 branch section, 99 bypass pipe return branch section, 101 controller .

Claims

A heating circulation circuit to which a hot water storage tank and a heat pump for heating water in the hot water storage tank are connected;
A heat-dissipation circuit in which a take-out unit at the top of the hot water storage tank, a heat exchanger connected to a load terminal, a pump, a main flow rate adjusting unit and a return unit at a predetermined position of the hot water storage tank are sequentially connected by piping,
Temperature detecting means for detecting a water temperature in the pipe near the return portion of the hot water storage tank of the heat radiation circulation circuit or a water temperature at a predetermined position in the hot water storage tank;
A heat pump system comprising: a control unit that controls the flow rate adjusting unit so that the water temperature detected by the temperature detecting unit becomes a predetermined temperature.

A heating circulation circuit to which a hot water storage tank and a heat pump for heating water in the hot water storage tank are connected;
A heat-dissipation circuit in which a take-out unit at the top of the hot water storage tank, a heat exchanger connected to a load terminal, a pump, a main flow rate adjusting unit and a return unit at a predetermined position of the hot water storage tank are sequentially connected by piping,
Return water temperature detection means for detecting a water temperature in the pipe near the return portion of the hot water storage tank of the heat radiation circulation circuit,
Hot water tank temperature detection means for detecting the water temperature at a predetermined position in the hot water tank,
Control means for controlling the water temperature detected by said return water temperature detection means to be substantially the same as the water temperature detected by said hot water storage tank water temperature detection means.

The return part of a hot-water storage tank was arrange | positioned above the temperature boundary layer formed in the hot-water storage tank after the boiling of the water of a hot-water storage tank, and before starting use of a load terminal. 2. The heat pump system according to 2.

A tapping pipe provided by branching from a pipe near the take-out portion of the heat radiation circulation circuit,
An opening / closing means or a flow rate adjusting means provided between the tapping portion and the branch portion of the tapping pipe and the pipe,
The control means stops the pump of the heat radiation circulation circuit, opens the main flow rate adjusting means, and when the detected temperature of the hot water storage tank water temperature detecting means is equal to or higher than a predetermined temperature, sets the opening / closing means or the flow rate adjusting means. The heat pump system according to any one of claims 1 to 3, wherein the heat pump system is closed, and the opening / closing means or the flow rate adjusting means is opened when the detected temperature is lower than the set temperature.

A tapping pipe provided by branching from a pipe near the take-out portion of the heat radiation circulation circuit,
A bypass pipe branched from the tapping pipe and connected above the return portion of the heat radiation circuit of the hot water storage tank via opening / closing means or flow rate adjusting means for the bypass pipe;
An opening / closing means or a flow rate adjusting means provided between the tapping pipe and a branch of the pipe near the take-out section and a branch of the bypass pipe and the tapping pipe;
Hot water storage tank temperature detection means near the bypass pipe for detecting the temperature near the connection of the bypass pipe in the hot water storage tank,
When simultaneously performing the heat radiation operation and tapping, the control means closes the opening / closing means or the flow rate adjusting means, activates the pump of the heat radiation circulation circuit, opens the main flow rate adjusting means, and adjusts the temperature of the hot water tank water near the bypass pipe. When the detected temperature of the detecting means is equal to or higher than a predetermined temperature, the opening / closing means or the flow rate adjusting means for the bypass pipe is opened, and when the detected temperature is lower than the set temperature, the opening / closing means or the flow rate adjusting means is opened. The heat pump system according to claim 1, wherein the heat pump system is open.

Mixing means for mixing the water supplied from the water absorption pipe provided in the tapping pipe or a flow rate adjusting means capable of adjusting the flow rates of both the supply water and the tapping water;
Tap water temperature detection means for detecting the water temperature of the tap pipe downstream of the mixing means or the flow rate adjustment means,
6. The heat pump system according to claim 4, wherein the control means controls the mixing means or the flow rate adjusting means such that the temperature detected by the tapping water temperature detecting means becomes a predetermined water temperature.

7. The hot water storage tank according to claim 1, wherein a return portion of the hot water storage tank is provided above the hot water storage tank, and a return pipe in the hot water storage extending from the return portion to the inside of the hot water storage tank is provided. Heat pump system.

The heat pump system according to claim 1, wherein a refrigerant of the heat pump is CO ₂ .