JP2004286307A

JP2004286307A - Storage type water heater

Info

Publication number: JP2004286307A
Application number: JP2003079333A
Authority: JP
Inventors: Satoru Tsurumaki; 悟鶴巻; Noboru Ogawa; 昇小川; Kei Maeda; 圭前田; Masami Shimada; 政美島田
Original assignee: Corona Corp
Current assignee: Corona Corp
Priority date: 2003-03-24
Filing date: 2003-03-24
Publication date: 2004-10-14

Abstract

<P>PROBLEM TO BE SOLVED: To provide a storage type water heater for effectively using intermediate hot water in a hot water storage tank for supplying hot water. <P>SOLUTION: This storage type water heater has a plurality of intermediate water return ports 25 and 26 of a vertical position for returning the cooled intermediate hot water to the hot water storage tank 2 between a water supply pipe 9 and a hot water feeding pipe 8 by using hot and cold water in the hot water storage tank 2 as a heat source, a return switching means 24 for selecting any one of the plurality of these intermediate hot water return ports 25 and 26, intermediate hot water feeding ports 38 and 39 vertically arranged in a plurality in an intermediate position higher than the water supply pipe 9 of the hot water storage tank 2, and lower than the hot water feeding pipe 8, a switching means 37 for selecting any one of the plurality of these intermediate hot water feeding ports 38 and 39, an intermediate hot water mixing valve 34 for mixing high temperature water from the hot water feeding pipe 8 with the hot and cold water from the intermediate hot water feeding port 38 or 39 selected by the switching means 37 to the optional prescribed temperature, and a hot water supply mixing valve 41 for supplying the hot water by mixing the hot water mixed by the intermediate hot water mixing valve 34 with low temperature water from a bypass pipe 42 branching off from the water supply pipe 9 to the optional hot water supply preset temperature. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は貯湯タンク内の湯水を熱源とする熱交換器を備えた貯湯式給湯装置に関するものである。
【０００２】
【従来の技術】
従来よりこの種のものにおいては、図１２に示すようなものがあった。
ここで、１０１はヒートポンプ回路、１０２は貯湯タンクで、この貯湯タンク１０２下部から取り出した５〜２５℃程度の低温水をヒートポンプ回路１０１で７０〜９０℃程度に加熱して貯湯タンク１０２の上部から積層貯湯していくものである。
【０００３】
前記貯湯タンク１０２には、その下端に給水管１０３が接続され、また上端には出湯管１０４が接続されているものである。１０５は電動ミキシング弁で、出湯管１０４からの高温水と給水管１０３からの低温水をリモコン（図示せず）等で設定された任意の給湯設定温度に混合して給湯栓１０６から出湯するものである。
【０００４】
１０７は暖房あるいは風呂の追焚き／保温の熱源としての熱交換器で、出湯管１０４から分岐した熱交往き管１０８および給水管１０３に合流する熱交戻り管１０９により貯湯タンク１０２と循環可能に接続されており、貯湯タンク１０２内の高温水を熱交換器１０７に流入させて暖房回路あるいは風呂の追焚き／保温回路等の２次側回路（図示せず）の温水を加熱するものである。
【０００５】
そして、貯湯タンク１０２の上部から取り出された高温水は、前記熱交換器１０７で熱交換されて温度低下し、３０〜５０℃程度の中温水となって貯湯タンク１０２の下部から貯湯タンク１０２内に戻るものである。
【０００６】
なお、このような従来の貯湯式給湯装置にかかる公知の刊行物を本願出願人は発見することができないが、貯湯タンク内に貯湯された高温水を熱源として暖房を行うものとして例えば特許文献１が挙げられる。
【０００７】
【特許文献１】
特許２６６３６３７号（図１）
【０００８】
【発明が解決しようとする課題】
しかし、この従来のものでは、熱交換器１０７での熱交換により３０〜５０℃程度の中温水が貯湯タンク１０２に貯まっていくが、この中温水は暖房あるいは追焚きの熱源として利用するには温度が低いため適さず、しかも湯切れするまで給湯を行わないと容量当たりの保有熱量が少ない中温水がいつまでも貯湯タンク１０２内に残留し、貯湯タンク１０２の保有熱量を減らしてしまい貯湯タンク容量の有効利用ができず、さらに貯湯タンク１０２内の水の沸き上げを行う場合、中温水をヒートポンプ回路１０１で再加熱するには温度が高いため効率が悪く、ヒートポンプ式給湯装置のＣＯＰ（エネルギー消費効率）を低下させてしまうという課題があり、また、熱交換後の中温水が給水管１０３を利用して貯湯タンク１０２に戻され、該貯湯タンク１０２の底部から中温水が溜まり、使用状況にもよるが高温水と中温水との間に低温水がサンドイッチされる状況もあり、さらに中温水の使用ができないという要因にもなるものであった。
【０００９】
【課題を解決するための手段】
そこで、本発明はこれらの課題を解決するために、請求項１では、給水管が下端部に接続されていると共に貯湯している湯水を流出させる出湯管が上端部に接続されている貯湯タンクと、この貯湯タンク内の湯水を高温に加熱する加熱手段と、前記貯湯タンク内の湯水を熱源として使用し温度低下した中温水を、給水管と出湯管の間の貯湯タンクに戻す上下位置の複数の中温水戻し口と、この複数の中温水戻し口の何れか１つを選択する戻し切換手段と、前記貯湯タンクの前記給水管よりも高く且つ前記出湯管よりも低い中間位置に上下に複数設けられている中温水出湯口と、この複数の中温水出湯口の何れか１つを選択する出湯切換手段と、前記出湯管からの高温水と前記出湯切換手段で選択された中温水出湯口からの湯水とを任意の所定温度に混合する中温水混合弁と、前記中温水混合弁で混合された湯と前記給水管から分岐されたバイパス管からの低温水とを任意の給湯設定温度に混合して給湯させる給湯混合弁とを備えたものである。
【００１０】
これにより、熱源に使用後の中温水は貯湯タンク内の高温水下方で、その温度に応じた中温水戻し口を選択して最適な位置に戻されるものであり、更に貯湯タンクの中間部の多数の中温水出湯口の何れかから出湯するので、貯湯タンク上部に貯められた高温水を貯めたままで、その下に貯まっている温度の低下した中温水を優先して給湯することができ、しかも、高温水の下に貯まっている中温水の貯められている高さが上下しても、この中温水の貯められた高さに近い中温水出湯口を切換手段により選択して出湯させることが可能で、貯湯タンク内の中温水を余すことなく給湯に用いることが可能となる。
【００１１】
また、請求項４では、前記加熱手段を二酸化炭素冷媒を用いたヒートポンプ回路として超臨界ヒートポンプサイクルを構成すると共に、前記貯湯タンクと前記ヒートポンプ回路とをヒーポン循環回路にて湯水が循環可能に接続し、前記貯湯タンク下部からの湯水を前記ヒートポンプ回路で加熱して前記貯湯タンク上部へ戻すよう構成したものとした。
【００１２】
これにより、貯湯タンク内の中温水は優先的に給湯されて、貯湯タンク下部には給水管からの低温水が貯められることとなるので、必ず低温水から沸き上げることができ、沸き上げの効率が向上しヒートポンプ回路のＣＯＰ（エネルギー消費効率）が良くなるものであると共に、ヒートポンプ回路によって高効率に高温まで沸き上げることができる。
【００１３】
【発明の実施の形態】
次に、本発明の一実施形態の貯湯式給湯装置を図１〜図１０に基づき説明する。なお、図２〜図１０中の貯湯タンク内にハッチングした斜線は低温水、二重斜線は中温水、三重斜線は高温水を示し、矢印は湯水の流れ方向を示すものである。
【００１４】
この貯湯式給湯装置は、時間帯別契約電力の電力単価が安価な深夜時間帯に湯水を沸き上げて貯湯し、この貯湯した湯水を給湯に用いるもので、１は湯水を貯湯する貯湯タンク２を備えた貯湯タンクユニット、３は貯湯タンク内の湯水を加熱するヒートポンプユニット、４は台所や洗面所等に設けられた第１給湯端たる給湯栓、５はこの給湯栓４の近傍に設けられた給湯リモコン、６は浴槽、７は浴室に設けられたふろリモコンである。
【００１５】
前記貯湯タンクユニット１の貯湯タンク２は、上端に出湯管８と、下端に給水管９とが接続され、さらに、下部にヒーポン循環回路を構成するヒーポン往き管１０と、上部にヒーポン循環回路を構成するヒーポン戻り管１１とか接続され、前記ヒートポンプユニット３によってヒーポン往き管１０から取り出した貯湯タンク２内の湯水を沸き上げてヒーポン戻り管１１から貯湯タンク２内に戻して貯湯され、給水管９からの給水により貯湯タンク２内の湯水が押し上げられて貯湯タンク２内上部の高温水が出湯管８から押し出されて給湯されるものである。
【００１６】
前記ヒートポンプユニット３は、圧縮機１２と凝縮器としての冷媒−水熱交換器１３と電子膨張弁１４と強制空冷式の蒸発器１５で構成された加熱手段としてのヒートポンプ回路１６と、貯湯タンク２内の湯水を前記ヒーポン往き管１０およびヒーポン戻り管１１を介して冷媒−水熱交換器１３に循環させるヒーポン循環ポンプ１７と、それらの駆動を制御するヒーポン制御部１８とを備えており、ヒートポンプ回路１６内には冷媒として二酸化炭素が用いられて超臨界ヒートポンプサイクルを構成しているものである。なお、冷媒に二酸化炭素を用いているので、低温水を電熱ヒータなしで約９０℃の高温まで沸き上げることが可能なものである。
【００１７】
ここで、前記冷媒−水熱交換器１３は冷媒と被加熱水たる貯湯タンク２内の湯水とが対向して流れる対向流方式を採用しており、超臨界ヒートポンプサイクルでは熱交換時において冷媒は超臨界状態のまま凝縮されるため効率良く高温まで被加熱水を加熱することができ、被加熱水の冷媒−水熱交換器１３入口温度と冷媒の出口温度との温度差が一定になるように前記減圧器１４または圧縮機１２を制御することで、被加熱水の冷媒−水熱交換器１３の入口温度が５〜２０℃程度の低い温度であるとＣＯＰ（エネルギー消費効率）が３．０以上のとても良い状態で被加熱水を加熱することが可能なものである。
【００１８】
１９は前記浴槽６の湯水を加熱するための熱交換器で、その一次側には貯湯タンク２上部に接続された高温水往き管２０と貯湯タンク２下部に接続された中温水戻り管２１とが接続されて熱交循環回路２２を構成し、中温水戻り管２１途中に設けられた熱交循環ポンプ２３の作動により貯湯タンク２から取り出した高温水を熱交換器１９に循環させ、熱交換により温度低下した中温水を再び貯湯タンク２内に戻すものである。
【００１９】
ここで、前記中温水戻り管２１は戻し切換手段たる戻し口切換弁２４を介して貯湯タンク２の中間位置の上下に設けられた第１中温水戻し口２５と第２中温水戻し口２６に接続され、何れか一方の戻し口から貯湯タンク２の中間位置付近に戻して貯湯するものであり、何れの戻し口から戻すかは、中温水戻し管２１に備えた中温水温度センサ２７で戻る中温水の温度を検出し、その温度に応じて戻し切換弁２４を切換るものである。
【００２０】
前記熱交換器１９の二次側には、浴槽６の湯水を循環可能にふろ往き管２８とふろ戻り管２９より構成されるふろ循環回路３０が接続され、ふろ戻り管２９途中に設けられたふろ循環ポンプ３１の作動により浴槽６の湯水が熱交換器１９に循環されて、一次側の高温水により加熱されて浴槽６内の湯水の保温あるいは追焚きが行われるものである。なお、３２はふろ戻り管２９を循環する浴槽６の湯水の温度を検出するふろ温度センサである。
【００２１】
次に、３３は前記中温水戻り管２１より高く前記出湯管８より低い貯湯タンク２の中間位置に接続された中温水出湯管で、前記熱交換器１９で二次側と熱交換して温度低下した中温水を貯湯タンク２から出湯するものである。
【００２２】
３４は、前記中温水出湯管３３の下流に設けられた中温水混合弁で、貯湯タンク２中間位置付近の中温水と貯湯タンク２上端に接続された出湯管８からの高温水とを、その下流の第１出湯管３５に設けた出湯温度センサ３６で検出する湯温が、給湯リモコン５またはふろリモコン７でユーザーが設定した給湯設定温度またはふろ設定温度（第２給湯設定温度）より一定温度高い温度である任意の所定温度になるように混合比率を制御するものである。
【００２３】
ここで、前記中温水出湯管３３は出湯切換手段たる出湯口切換弁３７を介して貯湯タンク２の中間位置の上下で、第２中温水戻し口２６近傍に設けられた第１中温水出湯口３８と、第１中温水戻し口２５近傍に設けられた第２中温水出湯口３９に接続され、何れか一方の出湯口から貯湯タンク２の中間位置付近に貯められている中温水を中温水混合弁３４に向けて出湯するものであり、下方の第１中温水出湯口３８より少し下方の貯湯タンク２側面に設けられた中温水出湯温度センサ４０の検出する温度に応じて出湯口切換弁３７を切換えるようにしている。
【００２４】
次に、４１は第１出湯管３５からの湯水と給水管９から分岐された第１バイパス管４２からの低温水を混合する電動ミキシング弁より構成された給湯混合弁であり、その下流の給湯管４３に設けた給湯温度センサ４４で検出した湯温が給湯リモコン５またはふろリモコン７でユーザーが設定した給湯設定温度になるように混合比率を制御するものである。
【００２５】
また、４５は前記第１出湯管３５から分岐された第２出湯管４６からの湯水と、給水管９から分岐された第２バイパス管４７からの低温水とを混合する電動ミキシング弁より構成されたふろ混合弁であり、その下流側の前記ふろ循環回路３０に連通された第２給湯端たる湯張り管４８に設けた湯張り温度センサ４９で検出した湯温がふろリモコン７でユーザーが設定したふろ設定温度になるように混合比率を制御するものである。
【００２６】
そして、前記湯張り管４８には、ふろ循環回路３０を介した浴槽６への湯張りの開始／停止を行う湯張り弁５０と、浴槽６への湯張り量をカウントするふろ流量カウンタ５１が設けられているものである。
【００２７】
次に、５２は貯湯タンク２の上下方向に複数個配置された貯湯温度センサで、この貯湯温度センサ５２が検出する温度情報によって、貯湯タンク２内にどれだけの熱量が残っているかを検知し、そして貯湯タンク２内の上下方向の温度分布を検知するものである。
【００２８】
前記給湯リモコン５およびふろリモコン７には、給湯設定温度を設定する給湯温度設定スイッチ５３、５４、およびふろ設定温度を設定するふろ温度設定スイッチ５５、５６がそれぞれ設けられていると共に、浴槽６へふろ設定温度の湯をふろリモコン７の湯張り量設定スイッチ（図示せず）で設定された湯張り量だけ湯張りし所定時間保温させるふろ自動スイッチ５７、５８がそれぞれ設けられているものである。
【００２９】
５９は貯湯タンクユニット１内の各センサの入力を受け各アクチュエータの駆動を制御するマイコンを有した給湯制御部である。この給湯制御部５５に前記給湯リモコン５およびふろリモコン７が無線または有線により接続されユーザーが任意の給湯設定温度およびふろ設定温度を設定できるようにしているものである。
【００３０】
なお、６０は貯湯タンク２の過圧を逃す過圧逃し弁、６１は給水の温度を検出する給水温度センサ、６２は給水の圧力を減圧する減圧弁、６３は給湯する湯水の量をカウントする給湯流量カウンタである。
【００３１】
次に、この一実施形態の作動を説明する。
まず、図２に示す沸き上げ運転について説明すると、深夜電力時間帯になって貯湯温度センサ５２が貯湯タンク２内に翌日に必要な熱量が残っていないことを検出すると、給湯制御部５９はヒーポン制御部１８に対して沸き上げ開始指令を発する。指令を受けたヒーポン制御部１８は圧縮機１２を起動した後にヒーポン循環ポンプ１７を駆動開始し、貯湯タンク２下部に接続されたヒーポン往き管１０から取り出した５〜２０℃程度の低温水を冷媒−水熱交換器１３で７０〜９０℃程度の高温に加熱し、貯湯タンク２上部に接続されたヒーポン戻り管１１から貯湯タンク２内に戻し、貯湯タンク２の上部から順次積層して高温水を貯湯していく。貯湯温度センサ５２が必要な熱量が貯湯されたことを検出すると、給湯制御部５９はヒーポン制御部１８に対して沸き上げ停止指令を発し、ヒーポン制御部１８は圧縮機１２を停止すると共にヒーポン循環ポンプ１７も停止して沸き上げ動作を終了するものである。
【００３２】
次に、図３に示す給湯運転について説明すると、給湯栓４を開くと、給水管９からの給水が貯湯タンク２内に流れ込む。そしてこのとき、貯湯タンク２内の中温水出湯温度センサ４０の位置には沸き上げられた高温水が貯められているので、中温水出湯温度センサ４０は所定値以上の温度を検出し、給湯制御部５９によって中温水切換弁３７が下側の第１中温水出湯口３８側に切換えられて、第１中温水出湯口３８から中温水出湯管３３を介して中温水混合弁３４へ高温水が押し出される。なお、貯湯タンク２内には上部に高温水、下部に低温水が貯められているが、その温度差により比重差が発生し、温度境界層を形成して比重の軽い高温水が上部に、比重の重い低温水が下部に位置するので、互いに混じり合うことはないものである。
【００３３】
ここで、給湯制御部５９は中温水出湯管３３からの湯水と出湯管８からの湯水を混合して中温水混合弁３４にて給湯リモコン５またはふろリモコン７で設定された給湯設定温度より一定温度以上高い温度となるように中温水混合弁３４を適当な比率に調整する。なお、ここでは、中温水出湯管３３から流入する湯が高温で給湯設定温度より高いため、中温水混合弁３４の出湯管８側を閉じることとなる。
【００３４】
そして、中温水混合弁３４から流出した湯は第１出湯管３５を介して給湯混合弁４０へ流入し、第１バイパス管４２からの低温水と混合され、給湯制御部５９が給湯混合弁（第１混合弁）４０の混合比率を調整し給湯設定温度の湯が給湯栓４から給湯される。そして、給湯栓４の閉止によって給湯が終了するものである。
【００３５】
ここで、中温水出湯温度センサ４０が所定値以下の温度を検出すると、図４に示すように給湯制御部５９が出湯口切換弁３７を上側の第２中温水出湯口３９側に切換え、第２中温水出湯口３９から高温水を出湯するようにしている。よって、下側の第１中温水出湯口３８付近に高温水が貯められている場合には第１中温水出湯口３８から出湯し、第１中温水出湯口３８付近に給水管９からの低温水が貯められている場合は第２中温水出湯口３９から出湯されることとなる。
【００３６】
また、前記中温水混合弁３４は給湯設定温度よりも一定温度以上高い温度の湯を第１出湯管３５に供給するようにしているので、第１中温水出湯口３８および第２中温水出湯口３９から出湯する湯水の温度が給湯設定温度よりも低い場合は、図５に示すように給湯制御部５９により中温水混合弁３４の混合比率が調整されて出湯管８からの高温水を用いて給湯設定温度よりも一定温度高い温度の湯を第１出湯管３５に供給するようにし、貯湯タンク２の中間位置からの出湯を優先し、貯湯タンク２の上部に貯められている高温水の使用を最小限に留め、熱源となる高温水をより多く確保することが可能となる。
【００３７】
次に、図６に示す浴槽６への湯張り運転について説明すると、給湯リモコン５またはふろリモコン７のふろ自動スイッチ５７、５８の何れかが操作されると、給湯制御部５９が湯張り弁５０を開弁する。そして、給水管９からの給水が貯湯タンク２内に流れ込む。そしてこのとき、貯湯タンク２内の中温水出湯温度センサ４０の位置には沸き上げられた高温水が貯められているので、中温水出湯温度センサ４０は所定値以上の温度を検出し、給湯制御部５９によって中温水切換弁３７が下側の第１中温水出湯口３８側に切換えられて、第１中温水出湯口３８から中温水出湯管３３を介して中温水混合弁３４へ高温水が押し出される。
【００３８】
ここで、給湯制御部５９はふろ自動スイッチ５７、５８の入力を受けると、中温水出湯管３３からの湯水と出湯管８からの湯水を混合して中温水混合弁３４にて給湯リモコン５またはふろリモコン７で設定されたふろ設定温度より一定温度以上高い温度となるように中温水混合弁３４を適当な比率に調整するようにしている。なお、ここでは、中温水出湯管３３から流入する湯が高温でふろ設定温度より高い温度であるため、中温水混合弁３４の出湯管８側を閉じることとなる。
【００３９】
そして、中温水混合弁３４から流出した湯は第１出湯管３５を介して第２出湯管４６へ出湯される。そして第２出湯管４６からの高温水はふろ混合弁４５へ流入し、第２バイパス管４７からの低温水と混合され、給湯制御部５９がふろ混合弁４５の混合比率を調整し、ふろ設定温度の湯が湯張り管４８からふろ循環回路３０を介して浴槽６へ湯張りされる。ここで、中温水出湯温度センサ４０が所定値以下の温度を検出すると、図４で説明した給湯動作の場合と同じく給湯制御部５９が出湯口切換弁３７を上方の第２中温水出湯口３８側に切換え、第２中温水出湯口３８から高温水を出湯するようにしている。
【００４０】
そして、湯張り管４８途中に設けられたふろ流量カウンタ５１が所定の湯張り量をカウントすると給湯制御部５９が湯張り弁５０を閉弁して湯張り運転を終了し、中温水混合弁３４での任意の混合温度を給湯設定温度よりも一定温度高い温度となるようにするものである。
【００４１】
次に、図７に示すふろの保温運転あるいは追焚き運転について説明すると、前記の浴槽６への湯張り運転に引き続き、給湯制御部５９は一定時間毎にふろ循環ポンプ３１を駆動し、浴槽６内の湯温をふろ温度センサ３２により検出する。そしてふろ温度センサ３２の検出する温度がふろ設定温度より所定値以上低下していると、給湯制御部５９は熱交循環ポンプ２７およびふろ循環ポンプ３０を駆動開始し、高温水往き管２０から取り出した高温水を熱交換器１９に流入させ、二次側の浴槽水と熱交換させふろの保温運転あるいは追焚き運転を行う。そして、熱交換により温度低下した中温水が中温水戻り管２１を介して貯湯タンク２下部に戻り、高温水と入れ替わる形で高温水と中温水の境界面を押し上げるようにして中温水が貯湯されるものである。なお、貯湯タンク２内には上部に高温水、中間部に中温水、下部に低温水が貯められているが、その温度差が２０℃程度あれば比重差が発生し、温度境界層を形成して比重の軽い高温水が上部に、中間の中間水が中間部に、比重の重い低温水が下部に位置するので、互いに混じり合うことはないものである。
【００４２】
更にこの時、熱交換器１９に流入する浴槽水の温度によって、中温水戻り管２１から貯湯タンク２へ戻る中温水温度も異なって来るので、この温度を中温水温度センサ２７で検出し４０℃を基準値として戻し切換弁２４を制御し、４０℃未満では下の第１中温水戻し口２５から貯湯タンク２下方へ中温水を戻し、４０℃以上では上の第２中温水戻し口２６から貯湯タンク２中間部へ中温水を戻すものであり、これにより、温度差のある中温水の混ざりを防止すると共に、この混ざりの水流による高温及び低温境界層の破壊を阻止出来、切換方式で温度の違う複数の中温水を優先して使用するものでは、中温水の混ざりがないぶん極めて使用勝手が良く、中温水の使用が効率良く行えるものである。
【００４３】
そして、二次側では、熱交換器１９にて加熱された浴槽水が浴槽６へ戻って浴槽６内を昇温し、ふろ温度センサ３２で検出する温度がふろ設定温度に達すると、給湯制御部５９は熱交循環ポンプ２７およびふろ循環ポンプ３０を駆動停止して保温運転あるいは追焚き運転を停止する。
【００４４】
次に、貯湯タンク２内に温度差がある中温水が貯められた後の給湯運転について説明する。図８に示すように、第１中温水出湯口３８付近に中温水が貯められて中温水出湯温度センサ４０が中温水を検出している場合は、出湯口切換弁３７は第１中温水出湯口３８側に切換えられ、給湯混合水栓３の開栓により、給水管９からの給水が貯湯タンク２内に流れ込むと同時に、第１中温水出湯口３８から中温水が押し出されて中温水出湯管３３を介して中温水混合弁３４へ流入する。
【００４５】
ここで、第１中温水出湯口３８から押し出される湯水の温度が給湯設定温度よりも低い場合は、中温水混合弁３４の混合比率が調整されて貯湯タンク２上端部の出湯管８からの高温水と混合されて給湯設定温度より一定温度高い温度の湯を供給するようにしている。
【００４６】
そして、中温水混合弁３４から流出した湯は第１出湯管３５を介して給湯混合弁４０へ流入し、第１バイパス管４２からの低温水と混合され、給湯制御部５９が給湯混合弁４０の混合比率を調整し給湯設定温度の湯が給湯栓４から給湯される。そして、給湯栓４の閉止によって給湯が終了するものである。
【００４７】
ここで、中温水温度センサ４０が所定値以下の温度を検出すると、図９に示すように、給湯制御部５９が出湯口切換弁３７を上側の第２中温水出湯口３９側に切換え、第２中温水出湯口３９から高温水を出湯するようにしている。よって、下側の第１中温水出湯口３８付近に高温水あるいは中温水が貯められている場合には第１中温水出湯口３８から出湯し、第１中温水出湯口３８付近に給水管９からの低温水が貯められている場合は第２中温水出湯口３９から出湯されることとなり、貯湯タンク２内の中温水を余すことなく給湯に用いることが可能となるものである。
【００４８】
また、前記中温水混合弁３４は給湯設定温度よりも一定温度以上高い温度の湯を第１出湯管３５に供給するようにしているので、第１中温水出湯口３８および第２中温水出湯口３９から出湯する湯水の温度が給湯設定温度よりも低い場合は、給湯制御部５９により中温水混合弁３４の混合比率が調整されて出湯管８からの高温水を用いて給湯設定温度よりも一定温度高い温度の湯を第１出湯管３５に供給するようにし、貯湯タンク２の中間位置からの出湯を優先し、貯湯タンク２の上部に貯められている高温水の使用を最小限に留め、熱源となる高温水をより多く確保することが可能となる。
【００４９】
次に、図１０に示す給湯動作中に湯張り運転が開始されるかまたは湯張り運転中に給湯動作が開始される同時給湯時は、給湯制御部５９が給湯設定温度とふろ設定温度を比較し、高い方の温度よりも一定温度高い温度を中温水混合弁３４での任意の所定温度とするようにしている。
【００５０】
このように、その時々の任意の給湯設定温度に応じて熱源として利用した中温水を可能な限り多く使って給湯を行うことができ、給湯が行われていない側の給湯設定温度が高い場合であっても、中温水混合弁で混合される任意の所定温度を、給湯設定温度の実際に給湯されている側の給湯設定温度よりも一定温度高い温度としているので、中温水を可能な限り多く使って給湯を行うことができると共に、複数の給湯端から同時給湯の要求がある時であっても、中温水を有効に使いつつ、各々の設定温度の湯を同時に給湯できるもので、熱源となる高温水を無駄に使用することを抑制して熱源としての能力を多く確保できるものである。
【００５１】
なお、前記下側の第１中温水戻し口２５は貯湯タンク２最下端の給水管９および下部のヒーポン往き管１０よりも高い位置に接続されているため、貯湯タンク２内に熱源として使われた中温水が戻されても、給湯の使用により貯湯タンク２下端から給水管からの低温水が流入することで貯湯タンク２の最下端には低温水が確保されることとなり、次回の沸き上げの際には必ず低温水から沸き上げることができるという効果がある。
【００５２】
このように、給湯の際に熱源として利用された中温水を高温水よりも優先して貯湯タンク２の途中から取り出して給湯するので、高温水を給湯しきるまで中温水を給湯できないと行った不具合がなく、給湯を行う度に貯湯タンク２内の中温水が減って給水管９からの低温水に入れ替わって、深夜の沸き上げ動作を行う時には沸き上げ効率の悪い中温水ではなく、温度の低い低温水をヒートポンプ回路１６で沸き上げることとなり、沸き上げの効率が向上しヒートポンプ式給湯装置としてのＣＯＰ（エネルギー消費効率）が良くなるものである。
【００５３】
なお、この一実施形態では、熱交換器１９と熱交循環ポンプ２３とふろ循環ポンプ２７とを貯湯タンクユニット１内に設けているが、貯湯タンクユニット１とは別体のユニット体に設けるようにしても良く、本発明の要旨を変更しない範囲での実施形態の変更をすることを妨げるものではない。
【００５４】
また、この一実施形態では、熱交換器１９の二次側にふろ循環回路２６を設けているが、床暖房パネルや温水式温風暖房器や浴室衣類乾燥器や温水式パネルコンベクタ、温水式パネルラジエータ等の暖房循環回路を設けても良く、要は貯湯タンク１６内の高温水の熱を熱交換器１９で熱交換して利用する熱機器であれば何でも良いものである。
【００５５】
さらに、貯湯タンク２内の湯水を加熱する手段としてヒートポンプ回路１６を例示しているが、これに限られず、貯湯タンク２内に直接配置した電熱ヒータや、貯湯タンク２内の湯水を循環させて電熱ヒータで加熱するようにしても良いものである。
【００５６】
また、この一実施形態では、中温水戻し口を２つしか設けていないが、これに限定されることなく、例えば中温水出湯口の数に対応するようにすれば、更に良好でスムーズな中温水の取り出しが図られるものである。
【００５７】
また、中温水出湯口も２つしか設けていないが、図１１に示す他の一実施形態のように、貯湯タンク側面に中温水出湯口を多数設けても良いものである。その場合、各中温水出湯口に対応する開閉弁を設けて多数ある中温水出湯口の何れか１つを選択する切換手段とすることができる。このとき、貯湯タンクの上下方向に複数個配置された貯湯温度センサの検出する温度によって貯湯タンク内の上下方向の温度分布を知り、これによって先の一実施形態と同じように、最適な中温水出湯口を選択することが可能なものである。
【００５８】
【発明の効果】
以上のように、本発明の請求項１によれば、熱源に使用後の中温水は貯湯タンク内の高温水下方で、その温度に応じた中温水戻し口を選択して最適な位置に戻され、温度差のある中温水の混ざりが防止され、更に貯湯タンクの中間部の多数の中間出湯口の何れかから出湯するので、貯湯タンク上部に貯められた高温水を貯めたままで、その下に貯まっている温度の低下した中温水を優先して給湯することができ、しかも、高温水の下に貯まっている中温水の貯められている高さが上下しても、この中温水の貯められた高さに近い中温水出湯口を切換手段により選択して出湯させることが可能で、貯湯タンク内の中温水を余すことなく給湯に用いることが可能となる。
【００５９】
また、請求項４によれば、貯湯タンク内の中温水は優先的に給湯されて、貯湯タンク下部には給水管からの低温水が貯められることとなるので、必ず低温水から沸き上げることができ、沸き上げの効率が向上しヒートポンプ回路のＣＯＰ（エネルギー消費効率）が良くなるものであると共に、ヒートポンプ回路によって高効率に高温まで沸き上げることができる。
【図面の簡単な説明】
【図１】本発明の一実施形態の概略構成図。
【図２】同一実施形態の沸き上げ運転の作動を説明する図。
【図３】同一実施形態の給湯運転の作動を説明する図。
【図４】同一実施形態の給湯運転の作動を説明する図。
【図５】同一実施形態の給湯運転の作動を説明する図。
【図６】同一実施形態の湯張り運転の作動を説明する図。
【図７】同一実施形態の保温／追焚き運転の作動を説明する図。
【図８】同一実施形態の貯湯タンク内に中温水が存在する場合の給湯運転の作動を説明する図。
【図９】同一実施形態の貯湯タンク内に中温水が存在する場合の給湯運転の作動を説明する図。
【図１０】同一実施形態の貯湯タンク内に中温水が存在する場合の給湯／湯張り同時運転の作動を説明する図。
【図１１】本発明の他の一実施形態の概略構成図。
【図１２】従来の貯湯式給湯装置の概略構成図。
【符号の説明】
２貯湯タンク
８出湯管
９給水管
１０ヒーポン往き管（ヒーポン循環回路）
１１ヒーポン戻り管（ヒーポン循環回路）
１６ヒートポンプ回路（加熱手段）
２０高温水往き管
２１中温水戻り管
２４戻し口切換弁（戻し切換手段）
２５第１中温水戻し口
２６第２中温水戻し口
２７中温水温度センサ
３３中温水出湯管
３４中温水混合弁
３７出湯口切換弁（出湯切換手段）
３８第１中温水出湯口
３９第２中温水出湯口
４１給湯混合弁
４２第１バイパス管[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a hot water supply type hot water supply apparatus provided with a heat exchanger using hot water in a hot water storage tank as a heat source.
[0002]
[Prior art]
Conventionally, this type has been shown in FIG.
Here, 101 is a heat pump circuit, 102 is a hot water storage tank, and the low-temperature water of about 5 to 25 ° C. taken out from the lower part of the hot water storage tank 102 is heated to about 70 to 90 ° C. by the heat pump circuit 101, and from the upper part of the hot water storage tank 102 The hot water is stored in layers.
[0003]
A water supply pipe 103 is connected to a lower end of the hot water storage tank 102, and a tapping pipe 104 is connected to an upper end thereof. Reference numeral 105 denotes an electric mixing valve which mixes high-temperature water from a tapping pipe 104 and low-temperature water from a water supply pipe 103 with an optional hot-water supply set temperature set by a remote controller (not shown) or the like, and discharges water from a hot-water tap 106. It is.
[0004]
Reference numeral 107 denotes a heat exchanger as a heat source for additional heating / heating of a heating or bath. The heat exchanger 107 can be circulated with the hot water storage tank 102 by a heat exchange pipe 108 branched from the hot water supply pipe 104 and a heat exchange pipe 109 joining the water supply pipe 103. The high-temperature water in the hot water storage tank 102 flows into the heat exchanger 107 to heat hot water in a secondary circuit (not shown) such as a heating circuit or a reheating / heating circuit of a bath. .
[0005]
Then, the high-temperature water taken out from the upper part of the hot water storage tank 102 is subjected to heat exchange in the heat exchanger 107 to lower the temperature, becomes medium-temperature water of about 30 to 50 ° C., and enters the hot water storage tank 102 from the lower part of the hot water storage tank 102. It is to return to.
[0006]
The applicant of the present application cannot find any known publication relating to such a conventional hot water supply type hot water supply apparatus. However, Patent Literature 1 discloses an example in which heating is performed using high-temperature water stored in a hot water storage tank as a heat source. Is mentioned.
[0007]
[Patent Document 1]
Patent No. 2663637 (FIG. 1)
[0008]
[Problems to be solved by the invention]
However, in this conventional apparatus, medium-temperature water of about 30 to 50 ° C. is stored in the hot water storage tank 102 by heat exchange in the heat exchanger 107. However, this medium-temperature water cannot be used as a heat source for heating or reheating. If the temperature is low, it is not suitable, and if hot water is not supplied until the hot water runs out, medium-temperature water having a small amount of retained heat per volume will remain in the hot water storage tank 102 forever, reducing the retained heat of the hot water storage tank 102 and reducing the capacity of the hot water storage tank. When the water in the hot water storage tank 102 cannot be effectively used and the water in the hot water storage tank 102 is to be further heated, the efficiency of the reheating of the medium-temperature water by the heat pump circuit 101 is low because the temperature is high, and the efficiency is low. ), And the medium-temperature water after the heat exchange is returned to the hot water storage tank 102 using the water supply pipe 103, and Medium-temperature water accumulates from the bottom of the tank 102, and depending on the use conditions, low-temperature water may be sandwiched between high-temperature water and medium-temperature water, and this may also cause the use of medium-temperature water to be impossible. Was.
[0009]
[Means for Solving the Problems]
Therefore, in order to solve these problems, according to the present invention, in claim 1, a hot water supply tank is connected to a lower end portion and a hot water supply tube for discharging hot water stored therein is connected to an upper end portion. And heating means for heating the hot water in the hot water storage tank to a high temperature, and the upper and lower positions for returning the medium-temperature water whose temperature has been lowered using the hot water in the hot water storage tank to the hot water storage tank between the water supply pipe and the tapping pipe. A plurality of medium-temperature water return ports, return switching means for selecting any one of the plurality of medium-temperature water return ports, and a vertical position at an intermediate position higher than the water supply pipe of the hot water storage tank and lower than the tapping pipe; A plurality of medium-temperature water taps, a hot-water switching means for selecting any one of the plurality of medium-temperature water taps, a high-temperature water from the hot-water pipe and a medium-temperature water outlet selected by the hot-water switching means. Arbitrary prescribed with hot water from the gate And a hot water mixing valve for mixing hot water mixed by the medium temperature water mixing valve and low temperature water from a bypass pipe branched from the water supply pipe to an optional hot water supply set temperature to supply hot water. It is provided with.
[0010]
Thereby, the medium-temperature water used as a heat source is returned to an optimal position by selecting a medium-temperature water return port corresponding to the temperature below the high-temperature water in the hot-water storage tank, and further, in the middle portion of the hot-water storage tank. Since hot water is discharged from any of a large number of medium-temperature hot water outlets, it is possible to supply high-temperature water stored in the upper part of the hot-water storage tank with priority given to the lower-temperature medium-temperature water stored underneath. In addition, even if the stored height of the medium-temperature water stored under the high-temperature water rises and falls, a medium-temperature water outlet close to the stored height of the medium-temperature water is selected by the switching means to supply hot water. It is possible to use the medium-temperature water in the hot water storage tank for hot water supply without leaving it.
[0011]
In claim 4, the heating means constitutes a supercritical heat pump cycle as a heat pump circuit using carbon dioxide refrigerant, and the hot water storage tank and the heat pump circuit are connected so that hot water can circulate in a heapon circulation circuit. The hot water from the lower part of the hot water storage tank is heated by the heat pump circuit and returned to the upper part of the hot water storage tank.
[0012]
As a result, the medium-temperature water in the hot-water storage tank is preferentially supplied with hot water, and low-temperature water from the water supply pipe is stored in the lower part of the hot-water storage tank. And the COP (energy consumption efficiency) of the heat pump circuit is improved, and the heat pump circuit can highly efficiently heat up to a high temperature.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, a hot water storage type hot water supply apparatus according to one embodiment of the present invention will be described with reference to FIGS. 2 to 10, hatched lines in the hot water storage tank indicate low-temperature water, double oblique lines indicate medium-temperature water, triple oblique lines indicate high-temperature water, and arrows indicate flow directions of hot water.
[0014]
This hot-water storage type hot water supply apparatus uses hot water to boil hot water at late night hours when the unit price of contracted power by time is low and uses the stored hot water for hot water supply, and 1 is a hot water storage tank 2 for storing hot water. , A heat pump unit for heating hot water in the hot water storage tank, 4 a hot water supply end serving as a first hot water supply end provided in a kitchen or a washroom, etc., and 5 provided near the hot water supply tap 4. A hot water supply remote control, 6 is a bathtub, and 7 is a bath remote control provided in the bathroom.
[0015]
The hot water storage tank 2 of the hot water storage tank unit 1 has a hot water supply pipe 8 connected to an upper end thereof, a water supply pipe 9 connected to a lower end thereof, and further has a heapon going pipe 10 constituting a heapon circulation circuit at a lower part and a heapon circulation circuit at an upper part. The heat pump unit 3 is connected to the heating water return pipe 11, and the hot water in the hot water storage tank 2 taken out of the heating water return pipe 10 is boiled by the heat pump unit 3 and returned to the hot water storage tank 2 from the heating water return pipe 11. The hot water in the hot water storage tank 2 is pushed up by the water supply from the hot water tank, and the high temperature water in the upper part of the hot water storage tank 2 is pushed out from the tapping pipe 8 and supplied.
[0016]
The heat pump unit 3 includes a heat pump circuit 16 as a heating means including a compressor 12, a refrigerant-water heat exchanger 13 as a condenser, an electronic expansion valve 14, and a forced air-cooled evaporator 15, and a hot water storage tank 2. A heat pump circulation unit 17 that circulates the hot and cold water in the refrigerant-water heat exchanger 13 via the heat pump return pipe 11 and the heat pump return pipe 11, and a heat pump control unit 18 that controls the driving of the heat pump. In the circuit 16, carbon dioxide is used as a refrigerant to constitute a supercritical heat pump cycle. Since carbon dioxide is used as the refrigerant, low-temperature water can be heated to a high temperature of about 90 ° C. without an electric heater.
[0017]
Here, the refrigerant-water heat exchanger 13 adopts a counter flow system in which the refrigerant and the hot water in the hot water storage tank 2 that is the heated water flow in opposition to each other. The water to be heated can be efficiently heated to a high temperature because it is condensed in a supercritical state, and the temperature difference between the refrigerant-water heat exchanger 13 inlet temperature and the refrigerant outlet temperature of the heated water becomes constant. By controlling the decompressor 14 or the compressor 12, the COP (energy consumption efficiency) becomes 3. If the inlet temperature of the refrigerant-water heat exchanger 13 to be heated is a low temperature of about 5 to 20C. It is possible to heat the heated water in a very good condition of 0 or more.
[0018]
Reference numeral 19 denotes a heat exchanger for heating the hot water in the bathtub 6. On its primary side, a high-temperature water feed pipe 20 connected to the upper part of the hot water storage tank 2 and a medium-temperature water return pipe 21 connected to the lower part of the hot water storage tank 2 are provided. Is connected to form a heat exchange circulation circuit 22, and the high-temperature water taken out of the hot water storage tank 2 is circulated to the heat exchanger 19 by the operation of the heat exchange circulation pump 23 provided in the middle-temperature water return pipe 21 to perform heat exchange. The medium-temperature water whose temperature has been lowered by the above operation is returned to the hot water storage tank 2 again.
[0019]
Here, the medium-temperature water return pipe 21 is connected to a first medium-temperature water return port 25 and a second medium-temperature water return port 26 provided above and below an intermediate position of the hot water storage tank 2 via a return port switching valve 24 serving as a return switching means. The hot water is connected and returned to the vicinity of the intermediate position of the hot water storage tank 2 from one of the return ports, and the hot water is returned from which return port is returned by the medium temperature water temperature sensor 27 provided in the medium temperature water return pipe 21. The temperature of the medium-temperature water is detected, and the return switching valve 24 is switched according to the detected temperature.
[0020]
On the secondary side of the heat exchanger 19, a bath circulation circuit 30 composed of a bath pipe 28 and a bath return tube 29 is connected so as to be able to circulate hot and cold water in the bathtub 6, and is provided in the middle of the bath return tube 29. The hot water in the bathtub 6 is circulated to the heat exchanger 19 by the operation of the bath circulation pump 31 and is heated by the high-temperature water on the primary side to keep the hot water in the bathtub 6 or to reheat the hot water. Reference numeral 32 denotes a bath temperature sensor for detecting the temperature of hot and cold water in the bathtub 6 circulating through the bath return pipe 29.
[0021]
Next, reference numeral 33 denotes a middle-temperature water tapping pipe connected to an intermediate position of the hot water storage tank 2 higher than the middle-temperature water return pipe 21 and lower than the tapping pipe 8, and exchanges heat with the secondary side in the heat exchanger 19 to change the temperature. The lowered middle-temperature water is discharged from the hot water storage tank 2.
[0022]
Reference numeral 34 denotes a middle-temperature water mixing valve provided downstream of the middle-temperature water tapping pipe 33, which serves to mix the middle-temperature water near the middle position of the hot-water storage tank 2 and the high-temperature water from the tapping pipe 8 connected to the upper end of the hot-water storage tank 2. The temperature of the hot water detected by the hot water temperature sensor 36 provided in the first hot water pipe 35 on the downstream side is a fixed temperature higher than the hot water set temperature or the hot water set temperature (second hot water set temperature) set by the user with the hot water remote controller 5 or the bath remote controller 7. The mixing ratio is controlled so as to be an arbitrary predetermined temperature which is a high temperature.
[0023]
Here, the middle-temperature water tapping pipe 33 is provided at a first middle-temperature water tap provided in the vicinity of the second middle-temperature water return port 26 above and below the intermediate position of the hot-water storage tank 2 via a tapping-switching valve 37 serving as a tapping-switching means. 38 and a second medium-temperature water outlet 39 provided in the vicinity of the first medium-temperature water return port 25, and the medium-temperature water stored in the vicinity of the intermediate position of the hot-water storage tank 2 from one of the ports is supplied to the medium-temperature water. The hot water is supplied to the mixing valve 34. The hot water outlet switching valve is provided in accordance with the temperature detected by the medium hot water tap temperature sensor 40 provided on the side of the hot water storage tank 2 slightly below the lower first intermediate hot water tap 38. 37 is switched.
[0024]
Next, reference numeral 41 denotes a hot water supply mixing valve constituted by an electric mixing valve for mixing the hot water from the first hot water pipe 35 and the low-temperature water from the first bypass pipe 42 branched from the water supply pipe 9, and the downstream hot water supply mixing valve. The mixing ratio is controlled so that the hot water temperature detected by the hot water temperature sensor 44 provided in the pipe 43 becomes the hot water set temperature set by the user with the hot water remote controller 5 or the bath remote controller 7.
[0025]
Reference numeral 45 denotes an electric mixing valve for mixing hot water from the second tapping pipe 46 branched from the first tapping pipe 35 and low-temperature water from the second bypass pipe 47 branched from the water supply pipe 9. A bath temperature detected by a bath temperature sensor 49 provided in a bath tube 48 serving as a second hot water supply end which is a bath mixing valve and communicated with the bath circulation circuit 30 downstream thereof is set by a user with the bath remote controller 7. The mixing ratio is controlled so as to reach the set bath temperature.
[0026]
The filling tube 48 is provided with a filling valve 50 for starting / stopping filling of the bathtub 6 through the bath circulation circuit 30 and a bath flow counter 51 for counting the filling amount of the bathtub 6. It is provided.
[0027]
Next, reference numeral 52 denotes a plurality of hot water storage temperature sensors arranged in the vertical direction of the hot water storage tank 2. The temperature information detected by the hot water storage temperature sensor 52 detects how much heat is left in the hot water storage tank 2. And the temperature distribution in the vertical direction in the hot water storage tank 2 is detected.
[0028]
The hot water supply remote controller 5 and the bath remote controller 7 are provided with hot water supply temperature setting switches 53 and 54 for setting a hot water supply setting temperature and bath temperature setting switches 55 and 56 for setting a bath setting temperature, respectively. Bath automatic switches 57 and 58 are respectively provided to fill the bath at the bath set temperature with the bath filling amount set by the bath remote setting switch (not shown) of the bath remote controller 7 and keep the temperature for a predetermined time. .
[0029]
Reference numeral 59 denotes a hot water supply control unit having a microcomputer that receives an input from each sensor in the hot water storage tank unit 1 and controls driving of each actuator. The hot water supply remote controller 5 and the bath remote controller 7 are connected to the hot water supply control unit 55 wirelessly or by wire so that a user can set any desired hot water supply set temperature and bath set temperature.
[0030]
Reference numeral 60 denotes an overpressure relief valve for releasing the overpressure of the hot water storage tank 2, 61 a supply water temperature sensor for detecting the temperature of the supply water, 62 a pressure reducing valve for reducing the pressure of the supply water, and 63 counting the amount of the supply water. It is a hot water supply flow counter.
[0031]
Next, the operation of this embodiment will be described.
First, the boiling operation shown in FIG. 2 will be described. When the hot-water storage temperature sensor 52 detects that the required amount of heat does not remain in the hot-water storage tank 2 in the midnight power time zone, the hot-water supply control unit 59 sets A boiling start command is issued to the control unit 18. Upon receiving the command, the heap control unit 18 starts driving the heapon circulation pump 17 after starting up the compressor 12, and cools the low-temperature water of about 5 to 20 ° C. taken out from the heap go-around pipe 10 connected to the lower part of the hot water storage tank 2 with the refrigerant. -Heated to a high temperature of about 70 to 90 ° C. in the water heat exchanger 13, returned to the hot water storage tank 2 from the heapon return pipe 11 connected to the upper part of the hot water storage tank 2, and sequentially laminated from the upper part of the hot water storage tank 2 to obtain high-temperature water To store hot water. When the hot water storage temperature sensor 52 detects that the required amount of heat is stored, the hot water supply control unit 59 issues a boiling stop command to the heapon control unit 18, and the heapon control unit 18 stops the compressor 12 and circulates the heapon. The pump 17 is also stopped to end the boiling operation.
[0032]
Next, the hot water supply operation shown in FIG. 3 will be described. When the hot water tap 4 is opened, the water supply from the water supply pipe 9 flows into the hot water storage tank 2. At this time, since the boiled high-temperature water is stored at the position of the medium-temperature water supply temperature sensor 40 in the hot water storage tank 2, the medium-temperature water supply temperature sensor 40 detects a temperature equal to or higher than a predetermined value, and performs hot water supply control. The medium-temperature water switching valve 37 is switched to the lower first medium-temperature water outlet 38 by the portion 59, and high-temperature water is supplied from the first medium-temperature water outlet 38 to the medium-temperature water mixing valve 34 via the medium-temperature water outlet pipe 33. Extruded. In the hot water storage tank 2, high-temperature water is stored in the upper part and low-temperature water is stored in the lower part. A difference in specific gravity occurs due to the temperature difference, and a high-temperature water having a low specific gravity is formed in the upper part by forming a temperature boundary layer. Since the low-temperature water having a high specific gravity is located at the lower portion, they do not mix with each other.
[0033]
Here, hot water supply control section 59 mixes hot and cold water from hot water tapping pipe 33 with hot water from hot tapping pipe 8, and makes constant at a hot water supply setting temperature set by hot water remote control 5 or bath remote control 7 at medium hot water mixing valve 34. The middle-temperature water mixing valve 34 is adjusted to an appropriate ratio so that the temperature becomes higher than the temperature. In this case, since the hot water flowing from the middle-temperature water tapping pipe 33 is high temperature and higher than the set hot water supply temperature, the tapping pipe 8 side of the middle-temperature water mixing valve 34 is closed.
[0034]
Then, the hot water flowing out of the middle-temperature water mixing valve 34 flows into the hot-water supply mixing valve 40 via the first tapping pipe 35, is mixed with the low-temperature water from the first bypass pipe 42, and the hot-water supply control section 59 causes the hot-water supply mixing valve ( The mixing ratio of the first mixing valve 40 is adjusted, and hot water at the set hot water supply temperature is supplied from the hot water tap 4. The hot water supply ends when the hot water tap 4 is closed.
[0035]
Here, when the medium-temperature hot water tap temperature sensor 40 detects a temperature equal to or lower than a predetermined value, the hot water supply control unit 59 switches the hot-water outlet switching valve 37 to the upper second middle hot water tap 39 side as shown in FIG. (2) High-temperature water is supplied from the medium-temperature water tap 39. Therefore, when high-temperature water is stored near the lower first medium-temperature water outlet 38, the hot water is discharged from the first medium-temperature water outlet 38, and the low-temperature water from the water supply pipe 9 is positioned near the first medium-temperature water outlet 38. When the water is stored, the hot water is discharged from the second medium-temperature water tap 39.
[0036]
Further, since the middle-temperature water mixing valve 34 supplies hot water having a temperature higher than a set temperature by a predetermined temperature or more to the first tapping pipe 35, the first middle-temperature water outlet 38 and the second middle-temperature water outlet are provided. When the temperature of the hot water discharged from the hot water 39 is lower than the set hot water supply temperature, the mixing ratio of the middle-temperature water mixing valve 34 is adjusted by the hot water control unit 59 as shown in FIG. Hot water at a certain temperature higher than the set hot water supply temperature is supplied to the first tapping pipe 35, and the tapping of hot water from an intermediate position of the hot water storage tank 2 is given priority, and the use of high-temperature water stored in the upper part of the hot water storage tank 2 is used. Is minimized, and more high-temperature water serving as a heat source can be secured.
[0037]
Next, the operation of filling the bathtub 6 with water shown in FIG. 6 will be described. When one of the bath automatic switches 57 and 58 of the hot water supply remote control 5 or the bath remote control 7 is operated, the hot water supply control unit 59 causes the hot water filling valve 50 to operate. Is opened. Then, the water supply from the water supply pipe 9 flows into the hot water storage tank 2. At this time, since the boiled high-temperature water is stored at the position of the medium-temperature water supply temperature sensor 40 in the hot water storage tank 2, the medium-temperature water supply temperature sensor 40 detects a temperature equal to or higher than a predetermined value, and performs hot water supply control. The medium-temperature water switching valve 37 is switched to the lower first medium-temperature water outlet 38 by the portion 59, and high-temperature water is supplied from the first medium-temperature water outlet 38 to the medium-temperature water mixing valve 34 via the medium-temperature water outlet pipe 33. Extruded.
[0038]
Here, when receiving the input of the bath automatic switches 57 and 58, the hot water supply control section 59 mixes the hot and cold water from the hot and cold water tapping pipe 33 and the hot and cold water from the hot tapping pipe 8, and controls the hot water supply remote control 5 or The middle-temperature water mixing valve 34 is adjusted to an appropriate ratio so that the temperature is higher than a set temperature set by the bath remote controller 7 by a certain temperature or more. In this case, since the hot water flowing from the middle-temperature water tapping pipe 33 is high temperature and higher than the bath set temperature, the tapping pipe 8 side of the middle-temperature water mixing valve 34 is closed.
[0039]
Then, the hot water flowing out of the middle-temperature water mixing valve 34 flows out to the second hot water pipe 46 via the first hot water pipe 35. Then, the high-temperature water from the second tapping pipe 46 flows into the bath mixing valve 45 and is mixed with the low-temperature water from the second bypass pipe 47. The hot-water supply control unit 59 adjusts the mixing ratio of the bath mixing valve 45, and sets the bath. Hot water of the temperature is filled from the filling pipe 48 to the bathtub 6 through the bath circulation circuit 30. Here, when the medium-temperature hot water tap temperature sensor 40 detects a temperature equal to or lower than a predetermined value, the hot-water supply control unit 59 sets the hot-water outlet switching valve 37 to the upper second intermediate hot water tap 38 as in the case of the hot water supply operation described with reference to FIG. Side so that high-temperature water is discharged from the second medium-temperature water tap 38.
[0040]
When the bath flow counter 51 provided in the middle of the filling pipe 48 counts a predetermined filling amount, the hot water supply control section 59 closes the filling valve 50 to end the filling operation, and the medium-temperature water mixing valve 34 Is set to a temperature that is higher than the set hot water supply temperature by a certain temperature.
[0041]
Next, the warming operation or the additional heating operation of the bath shown in FIG. 7 will be described. The hot water supply control unit 59 drives the bath circulation pump 31 at regular time intervals after the operation of filling the bathtub 6 with water. The temperature of the hot water inside is detected by the bath temperature sensor 32. When the temperature detected by the bath temperature sensor 32 is lower than the bath set temperature by a predetermined value or more, the hot water supply control unit 59 starts driving the heat exchange circulation pump 27 and the bath circulation pump 30 and removes the hot water from the high-temperature water supply pipe 20. The high-temperature water flows into the heat exchanger 19 and exchanges heat with the bathtub water on the secondary side to perform a warming operation or a reheating operation of the bath. Then, the medium-temperature water whose temperature has been lowered by the heat exchange returns to the lower part of the hot water storage tank 2 via the medium-temperature water return pipe 21, and the medium-temperature water is stored such that the boundary surface between the high-temperature water and the medium-temperature water is pushed up in such a way as to replace the high-temperature water. Things. In the hot water storage tank 2, high-temperature water is stored in the upper part, medium-temperature water is stored in the middle part, and low-temperature water is stored in the lower part. If the temperature difference is about 20 ° C., a specific gravity difference occurs, forming a temperature boundary layer. Since the high-temperature water having a low specific gravity is located at the upper portion, the intermediate water at the intermediate position is located at the intermediate portion, and the low-temperature water having a high specific gravity is located at the lower portion, they do not mix with each other.
[0042]
Further, at this time, the temperature of the medium-temperature water returning from the medium-temperature water return pipe 21 to the hot water storage tank 2 also varies depending on the temperature of the bathtub water flowing into the heat exchanger 19. The return switching valve 24 is controlled using the reference value as a reference value. When the temperature is lower than 40 ° C., the medium-temperature water returns from the lower first intermediate-temperature water return port 25 to the lower part of the hot water storage tank 2. The intermediate-temperature water is returned to the intermediate portion of the hot water storage tank 2, thereby preventing the mixing of the intermediate-temperature water having a temperature difference and preventing the destruction of the high and low temperature boundary layers due to the mixed water flow. In the case of using a plurality of medium-temperature waters with different priorities, the use of the medium-temperature water can be performed efficiently because the medium-temperature water is not mixed.
[0043]
Then, on the secondary side, when the bath water heated in the heat exchanger 19 returns to the bath 6 and the inside of the bath 6 is heated, and when the temperature detected by the bath temperature sensor 32 reaches the bath set temperature, hot water supply control is performed. The part 59 stops the heat exchange circulation pump 27 and the bath circulation pump 30 to stop the warming operation or the additional heating operation.
[0044]
Next, a hot water supply operation after medium-temperature water having a temperature difference is stored in hot water storage tank 2 will be described. As shown in FIG. 8, when medium-temperature water is stored in the vicinity of the first medium-temperature water tap 38 and the medium-temperature water tap temperature sensor 40 detects medium-temperature water, the tap switching valve 37 sets the first medium-temperature water tap. When the hot water mixing faucet 3 is opened, the water supply from the water supply pipe 9 flows into the hot water storage tank 2 and, at the same time, the medium-temperature hot water is pushed out from the first medium-temperature water tap 38 to discharge the medium-temperature hot water. It flows into the middle-temperature water mixing valve 34 via the pipe 33.
[0045]
Here, when the temperature of the hot water pushed out from the first medium-temperature water outlet 38 is lower than the set hot water supply temperature, the mixing ratio of the medium-temperature water mixing valve 34 is adjusted so that the temperature of the hot water from the tap pipe 8 at the upper end of the hot water storage tank 2 is increased. Hot water having a certain temperature higher than a set hot water supply temperature by being mixed with water is supplied.
[0046]
The hot water flowing out of the middle-temperature water mixing valve 34 flows into the hot-water supply mixing valve 40 via the first hot-water pipe 35 and is mixed with the low-temperature water from the first bypass pipe 42. And the hot water at the hot water set temperature is supplied from the hot water tap 4. The hot water supply ends when the hot water tap 4 is closed.
[0047]
Here, when the middle temperature water temperature sensor 40 detects a temperature equal to or lower than a predetermined value, as shown in FIG. 9, the hot water supply control unit 59 switches the tap outlet switching valve 37 to the upper second middle temperature tap hole 39 side, (2) High-temperature water is supplied from the medium-temperature water tap 39. Therefore, when high-temperature water or medium-temperature water is stored near the lower first medium-temperature water outlet 38, the hot water is discharged from the first medium-temperature water outlet 38, and the water supply pipe 9 is positioned near the first medium-temperature water outlet 38. When the low-temperature water is stored, the hot water is discharged from the second medium-temperature water outlet 39, so that the medium-temperature water in the hot-water storage tank 2 can be used for hot water supply without excess.
[0048]
Further, since the middle-temperature water mixing valve 34 supplies hot water having a temperature higher than a set temperature by a predetermined temperature or more to the first tapping pipe 35, the first middle-temperature water outlet 38 and the second middle-temperature water outlet are provided. When the temperature of the hot water discharged from 39 is lower than the set hot water supply temperature, the mixing ratio of the middle-temperature water mixing valve 34 is adjusted by the hot water supply control unit 59, and the hot water from the hot water outlet pipe 8 is used to keep the temperature constant. Hot water having a high temperature is supplied to the first tapping pipe 35, giving priority to tapping water from an intermediate position of the hot water storage tank 2, and minimizing the use of high-temperature water stored in the upper part of the hot water storage tank 2. It becomes possible to secure more high-temperature water as a heat source.
[0049]
Next, at the time of simultaneous hot water supply in which the hot water supply operation is started during the hot water supply operation shown in FIG. 10 or the hot water supply operation is started during the hot water supply operation, hot water supply control section 59 compares the hot water supply set temperature with the bath set temperature. Then, a temperature that is higher by a certain temperature than the higher temperature is set as an arbitrary predetermined temperature in the intermediate-temperature water mixing valve 34.
[0050]
In this manner, hot water can be supplied using as much of the medium-temperature water used as a heat source as much as possible according to the desired hot water supply set temperature at that time, and when the hot water supply set temperature on the non-hot water supply side is high. Even if there is, the predetermined temperature that is mixed by the middle-temperature water mixing valve is set to a temperature that is higher than the actual hot-water supply set temperature of the hot-water supply set temperature by a fixed temperature, so that as much medium-temperature water as possible is used. It can be used to supply hot water, and even when there is a demand for simultaneous hot water supply from multiple hot water supply ends, it can simultaneously supply hot water at each set temperature while using medium-temperature water effectively, Thus, it is possible to suppress the wasteful use of high-temperature water and secure a large capacity as a heat source.
[0051]
Since the lower first intermediate-temperature water return port 25 is connected to a position higher than the water supply pipe 9 at the lowermost end of the hot water storage tank 2 and the heapon going pipe 10 at the lower part, it is used as a heat source in the hot water storage tank 2. Even if the medium-temperature water is returned, low-temperature water flows from the lower end of the hot water storage tank 2 through the water supply pipe due to the use of hot water, so that low-temperature water is secured at the lowermost end of the hot water storage tank 2, and the next boil-up In this case, there is an effect that the water can always be heated from the low-temperature water.
[0052]
As described above, the medium-temperature water used as a heat source at the time of hot water supply is taken out of the middle of the hot water storage tank 2 with a higher priority than the high-temperature water, and the hot-water is supplied. Therefore, the medium-temperature water cannot be supplied until the high-temperature water is completely supplied. Every time hot water is supplied, the medium-temperature water in the hot water storage tank 2 decreases and is replaced with low-temperature water from the water supply pipe 9, and when performing the boiling operation at midnight, it is not medium-temperature water with low boiling efficiency but low temperature. The low-temperature water is boiled by the heat pump circuit 16, so that the efficiency of the boil-up is improved and the COP (energy consumption efficiency) as the heat pump type hot water supply device is improved.
[0053]
In this embodiment, the heat exchanger 19, the heat exchange circulation pump 23, and the bath circulation pump 27 are provided in the hot water tank unit 1. However, the heat exchanger 19, the heat exchange circulation pump 23, and the bath circulation pump 27 are provided in a unit body separate from the hot water storage tank unit 1. However, this does not prevent the embodiment from being changed without changing the gist of the present invention.
[0054]
Further, in this embodiment, the bath circulation circuit 26 is provided on the secondary side of the heat exchanger 19; however, a floor heating panel, a hot water type hot air heater, a bathroom clothes dryer, a hot water type panel convector, a hot water type A heating circulation circuit such as a panel radiator may be provided. In short, any heating device may be used as long as it exchanges heat of high-temperature water in the hot water storage tank 16 with the heat exchanger 19 for use.
[0055]
Further, the heat pump circuit 16 is illustrated as a means for heating the hot water in the hot water storage tank 2. However, the heat pump circuit 16 is not limited to this, and the electric heater disposed directly in the hot water storage tank 2 or the hot water in the hot water storage tank 2 is circulated. Heating may be performed by an electric heater.
[0056]
Further, in this embodiment, only two medium-temperature water return ports are provided. However, the present invention is not limited to this. It is intended to take out hot water.
[0057]
Although only two medium-temperature water taps are provided, a large number of medium-temperature water taps may be provided on the side surface of the hot water storage tank as in another embodiment shown in FIG. In that case, an opening / closing valve corresponding to each of the medium-temperature water taps may be provided as a switching means for selecting any one of a number of medium-temperature water taps. At this time, the temperature distribution in the up-down direction in the hot water storage tank is known from the temperatures detected by the plurality of hot water storage temperature sensors arranged in the vertical direction of the hot water storage tank. It is possible to select a tap.
[0058]
【The invention's effect】
As described above, according to the first aspect of the present invention, the medium-temperature water used as a heat source is returned to an optimum position by selecting a medium-temperature water return port corresponding to the temperature below the high-temperature water in the hot water storage tank. As a result, mixing of the medium-temperature water having a temperature difference is prevented, and the hot water is discharged from any of a number of intermediate taps in an intermediate portion of the hot-water storage tank. The hot water with lower temperature stored in the hot water can be supplied with priority, and even if the height of the hot water stored under the hot water rises or falls, this hot water is stored. It is possible to select a medium-temperature hot water outlet close to the given height by the switching means and to supply hot water, so that the medium-temperature water in the hot water storage tank can be used for hot water supply without excess.
[0059]
According to the fourth aspect, the medium-temperature water in the hot water storage tank is preferentially supplied with hot water, and low-temperature water from a water supply pipe is stored in a lower portion of the hot-water storage tank. In addition, the efficiency of boiling can be improved and the COP (energy consumption efficiency) of the heat pump circuit can be improved, and the heat pump circuit can efficiently raise the temperature to a high temperature.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an embodiment of the present invention.
FIG. 2 is a view for explaining the operation of the boiling operation of the same embodiment.
FIG. 3 is a diagram illustrating the operation of the hot water supply operation of the same embodiment.
FIG. 4 is a diagram illustrating the operation of the hot water supply operation of the same embodiment.
FIG. 5 is a view for explaining the operation of the hot water supply operation of the same embodiment.
FIG. 6 is a view for explaining the operation of the filling operation of the same embodiment.
FIG. 7 is a view for explaining the operation of the heat retention / reheating operation of the same embodiment.
FIG. 8 is a view for explaining the operation of the hot water supply operation when medium-temperature water is present in the hot water storage tank of the same embodiment.
FIG. 9 is a view for explaining the operation of the hot water supply operation when medium-temperature water is present in the hot water storage tank of the same embodiment.
FIG. 10 is a diagram illustrating the operation of simultaneous operation of hot water supply and hot water filling when medium-temperature water is present in the hot water storage tank of the same embodiment.
FIG. 11 is a schematic configuration diagram of another embodiment of the present invention.
FIG. 12 is a schematic configuration diagram of a conventional hot water supply type hot water supply apparatus.
[Explanation of symbols]
2 Hot water storage tank
8 tapping pipe
9 Water pipe
10 Hepon go pipe (heapon circulation circuit)
11 Heaton return pipe (Heapon circulation circuit)
16 Heat pump circuit (heating means)
20 Hot water pipe
21 Medium hot water return pipe
24 Return port switching valve (return switching means)
25 1st hot water return port
26 2nd warm water return port
27 Medium-temperature water temperature sensor
33 Medium-temperature water tap
34 Medium-temperature water mixing valve
37 Outlet switching valve (outlet switching means)
38 1st Medium Hot Water Outlet
39 2nd hot water outlet
41 Hot water mixing valve
42 1st bypass pipe

Claims

A hot water storage tank having a water supply pipe connected to a lower end thereof and a hot water supply pipe for discharging hot water stored therein connected to an upper end thereof; heating means for heating the hot water in the hot water storage tank to a high temperature; One of one of a plurality of middle-temperature water return ports at upper and lower positions for returning middle-temperature water whose temperature has been lowered by using hot water in the tank to a hot water storage tank between a water supply pipe and a tapping pipe, and Return switching means for selecting one of the hot water storage tanks, a plurality of middle-temperature water outlets provided vertically above and below an intermediate position higher than the water supply pipe and lower than the tap water pipe, and a plurality of the intermediate-temperature water outlets. Hot water switching means for selecting any one, a medium-temperature water mixing valve for mixing high-temperature water from the tapping pipe and hot-water from the medium-temperature water outlet selected by the hot-water switching means to an arbitrary predetermined temperature, Hot water mixed by the medium-temperature water mixing valve The hot water storage type hot water supply apparatus is characterized in that a hot water supply mixing valve for hot water are mixed in any hot water set temperature and low temperature water from the bypass pipe diverged from the water supply pipe.

2. The hot water supply apparatus according to claim 1, wherein the return switching unit is switched in accordance with a temperature of the returned intermediate temperature water detected by a medium temperature water sensor provided in the intermediate temperature water return pipe. 3.

2. The hot water storage type according to claim 1, wherein the return switching unit is switched in accordance with a temperature of the returned intermediate hot water detected by a medium temperature water temperature sensor provided in the intermediate temperature water return pipe and a position of a boundary layer of the hot water storage tank. 3. Water heater.

A supercritical heat pump cycle is configured as a heat pump circuit using a carbon dioxide refrigerant as the heating means, and the hot water storage tank and the heat pump circuit are connected so that hot water can circulate in a heap circulation circuit. 2. The hot water supply type hot water supply apparatus according to claim 1, wherein the hot water is heated by the heat pump circuit and returned to an upper portion of the hot water storage tank.