JP3632651B2

JP3632651B2 - Water heater

Info

Publication number: JP3632651B2
Application number: JP2001362207A
Authority: JP
Inventors: 啓次郎國本; 竹司渡辺; 龍太近藤; 松本　　聡; 敏今林
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2001-11-28
Filing date: 2001-11-28
Publication date: 2005-03-23
Anticipated expiration: 2021-11-28
Also published as: JP2003161518A

Description

【０００１】
【発明の属する技術分野】
本発明は、貯湯式温水器の貯湯熱を利用して浴槽の加熱が可能な給湯装置に関するものである。
【０００２】
【従来の技術】
貯湯式温水器の貯湯熱を利用して浴槽水の追焚きや保温を行うものとして特開平１１−８３１５６号公報に記載されているような給湯装置があった。この給湯装置は図３に示すように、上部と下部にヒータ２，３を有する貯湯タンク１を備え、貯湯タンク１の上部に熱交換器４を設けると共に、熱交換器４と浴槽５の間に循環路６を設け、浴槽５の追焚きや保温をする給湯装置であって、熱交換器４により、循環路６内の浴槽水と貯湯タンク１の湯を熱交換させるようにしている。一般家庭において浴槽水の追焚きに必要な熱量は、入浴時にすぐに温度を上げたいという要望から１０ｋＷ程度必要と考えられる。これに対して貯湯タンク１の熱を利用して浴槽水の追焚きを行えば充分に満足できる熱量が得られる。しかし、貯湯タンク１の湯は浴槽５への湯張りやシャワー等に使われるので、貯湯タンク１内の残湯は一定でなく、この残湯が少なくなれば、浴槽水の追焚きが困難になる。また浴槽水の追焚きを行うと残湯温度が低下するため、追焚き回数を重ねると熱交換される熱量が減少し、追焚きに掛かる時間がながくなり、残湯温度が浴槽水温に近付くと最後は追焚きできなくなってしまう。
【０００３】
この問題を解決するために、特開平１１−８３１５６号公報では浴槽水が循環路６内を循環しているときに、貯湯タンク１内の上部ヒータ２に通電するようにしている。また、熱交換をする前に貯湯タンク１上部の湯温を検知しておき、熱交換後に上部ヒータ２に通電して貯湯タンク１上部の湯温を元の温度に戻すようにしている。
【０００４】
しかし、上部ヒータ２の貯湯タンク１への取り付け位置が固定され、ヒータ容量に制限があるため、たとえばヒータ２で加熱する貯湯タンク１の容量が大きい場合（ヒータ２が低い位置に設けらている場合）は素早く湯温を元の温度にもどせないために、やはり追焚きに時間が掛かっていまう。また、ヒータ２で加熱する貯湯タンク１の容量が小さい場合（ヒータ２が高い位置に設けらている場合）は湯温の上昇は早いが追焚きによる温度低下も早く、浴槽水が冷えきってしまっている場合に追焚きができなくなってしまう問題があった。
【０００５】
また浴槽水の追焚きに必要な熱量は、浴槽の大きさや入浴頻度、気温などによりさまざまであり、それに必要な熱量も変わってくるが、従来例では貯湯タンク１内の残湯が少なくなった場合に浴槽水の追焚きに必要な熱量を確保するためのヒータ２の位置が固定されているために、熱量の過不足が生じてしまう問題があった。とくに貯湯タンクに熱交換器を内設して熱を利用する場合は貯湯タンクの湯温を高温に維持しないと、熱交換が充分に行えない。したがって高温の湯を無駄に沸き上げてしまうと放熱ロスが多くなる問題も抱えていた。
【０００６】
【発明が解決しようとする課題】
本発明は、上記従来の課題を解決するもので、貯湯式温水器の貯湯熱を効率よく利用して浴槽水の追焚きや保温を行う給湯装置を提供することを目的とする。
【０００７】
【課題を解決するための手段】
本発明は上記課題を解決するために、本発明の給湯装置は、貯湯タンクと、前記貯湯タンク内の湯水を加熱する加熱手段と、前記貯湯タンク内の湯水と熱交換を行う熱交換手段と、前記貯湯タンクの上部に設けた第１の出湯口と、前記貯湯タンクの中央部に設けた第２の出湯口と、前記貯湯タンク内の中間温度の残湯量を検出する残湯量センサを備え、前記残湯量センサの検出する中間温度の残湯量が所定量以上であれば、前記第２の出湯口から中間温度の残湯を出湯し、前記残湯量センサの検出する中間温度の残湯量が所定量以下であれば、前記第１の出湯口から出湯するものである。
【０００８】
上記発明によれば、第２の出湯口から先に出湯するので、中間温度の残湯が先に出湯され、第２の出湯口より下部の残湯が無くなるまで貯湯タンク上部の高温部の湯は使われないで、高温の貯湯が素早くでき、貯湯タンク全体の貯湯熱量が大きくできる。
【０００９】
【発明の実施の形態】
請求項１に記載の発明は、貯湯タンクと、前記貯湯タンク内の湯水を加熱する加熱手段と、前記貯湯タンク内の湯水と熱交換を行う熱交換手段と、前記貯湯タンクの上部に設けた第１の出湯口と、前記貯湯タンクの中央部に設けた第２の出湯口と、前記貯湯タンク内の中間温度の残湯量を検出する残湯量センサを備え、前記残湯量センサの検出する中間温度の残湯量が所定量以上であれば、前記第２の出湯口から中間温度の残湯を出湯し、前記残湯量センサの検出する中間温度の残湯量が所定量以下であれば、前記第１の出湯口から出湯するものである。
【００１０】
よって、第２の出湯口から先に出湯するので、中間温度の残湯が先に出湯され、第２の出湯口より下部の残湯が無くなるまで貯湯タンク上部の高温部の湯は使われないで、高温の貯湯が素早くでき、貯湯タンク全体の貯湯熱量が大きくできる。
【００１１】
また、第２の出湯口より下部の残湯が少なくなった場合に自動的に第１の出湯口から出湯するように切換えられるので、使用者は出湯口の切換を意識することなく自然に給湯できる。
【００１２】
また請求項２に記載の発明は、請求項１に記載の熱交換手段を、第２の出湯口より上部に設けたものである。これにより、第２の出湯口より下部の残湯が無くなるまで貯湯タンク上部の高温部の湯は使われないで、この第２の出湯口より上部の熱交換手段近傍は高温に維持でき、浴槽水の追焚きを行う際に熱交換効率の高く素早い追焚きができる。
【００１３】
また請求項３に記載の発明は、請求項２に記載の給湯装置において、貯湯タンク内の底部に設けた第１の取水口と、前記第１の取水口より上方でかつ熱交換手段より下方に設けた第２の取水口と、前記第１の取水口と前記第２の取水口とを切換える取水切換手段とを備えるものである。それによって、貯湯タンク内全体を沸き上げる場合は第１の取水口より水を取り出し、加熱手段により加熱した後供給口に戻すことで、貯湯タンクの残湯が再加熱されるのに時間はかかるが貯湯タンクの底部まで高温部が到達し貯湯タンク全体が高温部で満たされる。一方、切換手段により第２の取水口から水を取り出すようにすると、貯湯タンクの残湯が早い段階で第２の取水口に達し、再加熱されるので第２取水口より上方を高温に沸き上げるが素早くできる。したがって、貯湯タンクの残湯が少なく熱交換手段近傍の温度が低い状態でもすぐに高温に沸き増しできるので、浴槽水の追焚きも素早くできる。
【００１４】
また請求項４に記載の発明は、請求項２に記載の給湯装置において、第２の取水口より上方でかつ熱交換手段より下方に貯湯タンクの湯温を検出する温度検知手段とを備え、取水切換手段は、前記温度検知手段が所定温度以下を検出した場合に第１の取水口から前記第２の取水口へ切り換えるものである。それによって、熱交換手段の周辺の貯湯温度を所定温度以上に素早く加熱できるので、熱交換手段近傍の温度低下による浴槽水の追焚き熱量不足を未然に防止できる。
【００１５】
そしてまた請求項５に記載の発明は、加熱手段を、冷媒の圧力が臨界圧力以上となる超臨界ヒートポンプサイクルとし、前記臨界圧力以上に昇圧された冷媒により湯水循環手段による流水を加熱するように構成している。そして、超臨界ヒートポンプサイクルは、湯水循環手段の流水を高温（例えば９０℃）に加熱する場合、加熱前の流水温度が低いほど、高圧圧力が低くなることでサイクル効率（ＣＯＰ＝加熱能力／消費電力）が向上する。したがって、貯湯タンクに温度成層を形成し、低温部の水を超臨界ヒートポンプサイクルで加熱することにより、サイクル効率が向上し、省動力運転を行うことができる。また、中間温度の残湯も給湯により出湯してしまえば、超臨界ヒートポンプサイクルで加熱するのは低温部の水だけとなるので、より効率が向上する。
【００１６】
また、本発明は、上記構成に加え貯湯タンクに残湯量センサを設け、切換手段は、第２の出湯口より下部の残湯が所定量以下に減少した場合に、第１の出湯口から出湯するように切換えるようにしたものである。この発明によれば、第２の出湯口より下部の残湯が少なくなった場合に自動的に第１の出湯口から出湯するように切換えられるので、使用者は出湯口の切換を意識することなく自然に給湯できる。
【００１７】
【実施例】
以下本発明の実施例について、図面を参照しながら説明する。
【００１８】
（実施例１）
図１は本発明の実施例１における給湯装置の構成図を示す。本実施例は一般家庭用の給湯装置で、主に割安な深夜電力を利用して給湯の湯を貯留するもので、貯湯タンク１０と、浴槽１１と、ヒートポンプサイクルで構成される加熱手段１２から構成される。
【００１９】
給湯は、貯湯タンク１０底部の給水口１３から水道水が供給され、貯湯タンク１０上部に設けた第１の出湯口１４または中央部に設けた第２の出湯口１５からから出湯される。１６は出湯切換手段で、第１の出湯口１４と第２の出湯口１５を切換える３方弁１６ａと出湯切換制御手段１７より成っている。出湯切換制御手段１７は、残湯量センサ１８ａ，１８ｂ，１８ｃより貯湯タンク１０の残湯量を検出し、各残湯量センサ１８ａ，１８ｂ，１８ｃに残湯があれば第２の出湯口１５から出湯するように３方弁１６ａを制御し、第２の出湯口１５の直下の残湯量センサ１８ａが湯が無くなったことを検出した場合は、第１の出湯口１４から出湯するように３方弁１６ａを切換え制御する。これにより貯湯タンク１０内の湯は、まず第２の出湯口１５の下部が出湯され、その後上部が出湯される。
【００２０】
貯湯タンク１０内の沸き上げは、貯湯タンク１０の底部に設けた第１の取水口１９より水を取り出し、貯湯タンク１０上部の供給口２０より戻す湯水循環手段２１と、この湯水循環手段２１の流水を加熱する加熱手段１２により行う。具体的には、加熱手段１２の出口２１ａ近傍に設け、流水の加熱温度を検出する加熱センサ２１ｂの検出値を入力して、湯水循環手段２１の沸き上げポンプ２２と、加熱手段１２のヒートポンプサイクルを加熱制御手段２３により制御し、供給口２０に高温（例えば９０℃）の湯を戻すようにしている。これによって、貯湯タンク１０内が高温部２４と低温部２５に分かれ温度成層２６が形成され、沸き上げ運転にしたがって温度成層２６は貯湯タンク１０の下方に移動し、最終は貯湯タンク１０内が全て高温部２４になる。この貯湯タンク１０全体の沸き上げは主通電時間帯（例えば、時間帯別電灯の電気料金が安い２３時から翌朝の７まで）に予め設定し行うようにしている。そしてこの主通電時間帯以外の時間帯では貯湯タンク１０の残湯に応じて適宜沸き上げ運転が入るようになっている。
【００２１】
浴槽１１内の浴槽水２７の保温や追焚きをする場合は、貯湯タンク１０上部に内設した熱交換手段２８により吸熱し、浴水循環手段２９を介して熱交換手段２８からの熱を浴槽１１に供給する。
【００２２】
熱交換手段２８は、金属パイプをコイル状に成形した熱交換器を貯湯タンク１０内に配置したもので、この金属パイプ内を流れる浴槽水と貯湯タンク１０内の湯が熱交換する。
【００２３】
浴水循環手段２９は、浴槽１１と熱交換手段２８とをつなぎ循環回路を構成する往き管３０と、戻り管３１と、戻り管３１に設けた浴水ポンプ３２よりなり、浴槽水を熱交換手段２８に送り、加熱された浴槽水を浴槽１１に戻すように作用する。
【００２４】
３３は貯湯タンク１０の水を高い位置より取り出す第２の取水口で、第１の取水口１９より上方でかつ熱交換手段２８より下方に配置している。そして第１の取水口１９と第２の取水口３３とを切換える取水切換手段３４を設け、貯湯タンク１０上部だけを沸き上げたい場合に、湯水循環手段２１は第２の取水口３３より水を取り出し、加熱手段１２で高温に加熱した水を供給口２０に戻す。
【００２５】
３５は加熱切換制御手段、３６は第２の取水口３３より上方でかつ熱交換手段２８より下方の貯湯タンク１０内の湯温を検出する温度検知手段で、加熱切換制御手段３５は、温度検知手段３６の検出温度が所定温度（例えば６０℃）以下となった場合に、取水切換手段３４を駆動させて第２の取水口３３より取水できるように切換え、加熱制御手段２３を作動させて湯水循環手段２１を起動し、前記第２の取水口３３の上部の湯をを加熱するようにする。すなわち、貯湯タンク１０上部の残湯が少なくなった場合に、第２の取水口３３より上方だけを加熱できるので、温度上昇が早くなる。
【００２６】
加熱手段１２は、例えば炭酸ガスを冷媒として使用することにより、高圧側の冷媒圧力が冷媒の臨界圧以上となる超臨界ヒートポンプサイクルを使用している。このヒートポンプサイクルは圧縮機３７、水加熱用熱交換器３８、膨張弁３９、蒸発器４０等の機能部品により構成されている。圧縮機３７は、内蔵する電動モータ（図示しない）によって駆動され、吸引した冷媒を臨界圧力まで圧縮して吐出する。
【００２７】
水加熱用熱交換器３８は、冷媒と湯水循環手段２１を流れる水とを熱交換するもので、例えば冷媒が流れる冷媒通路４１と水が流れる流水通路４２とが２重管構造に設けられ、且つ冷媒の流れ方向と流水の流れ方向が対向するように構成された対向流式熱交換器である。膨張弁３９は、水加熱用熱交換器３８から流出する冷媒を減圧して蒸発器４０に供給する。蒸発器４０は、膨張弁３９で減圧された冷媒を大気との熱交換によって蒸発させる。
【００２８】
４３は３方弁１６ａから出湯される湯と給水管４４からの水道水を混合する混合弁で、混合温度を検出する混合温度センサ４５の検出値をフィードバックして所定の温度（例えば４０℃）に混合して出湯管４６に送出する。出湯管４６は蛇口４７やシャワー（図示せず）に接続される。
【００２９】
４８は出湯管４６と往き管３０を繋ぐ注湯管４９に設けられた開閉弁で、浴槽１１に湯張したり、差し湯する場合に、この混合弁４８を開放して行う。
【００３０】
以上実施例１の構成によれば、深夜の主通電時間帯に沸き上げられた貯湯タンク１０の湯が浴槽１１への湯張りやシャワー等に使われて残湯が少なくなっても、加熱制御手段２３により貯湯タンク１０内の温度成層２６を上部から下部に移動するように沸き増しできるので、熱交換手段２８の吸熱に必要な高温の湯を必要な量だけ沸き増しできる。したがって、熱交換手段２８の吸熱量が増し浴槽水２７の追焚きが素早くできる。
【００３１】
また、温度検知手段３６が所定温度（例えば６０℃）以下となった場合に、第２の取水口３３より取水して湯水循環手段２１を起動し、第２の取水口３３からの上の湯をを加熱するようにしているので、特に熱交換手段２８の周辺の貯湯温度を素早く加熱できる。したがって、たとえ貯湯タンク１０内の残湯が少なくなっても熱交換手段２８近傍に直ちに高温の湯が供給でき、温度低下による浴槽水の追焚き熱量不足を未然に防止できる。
【００３２】
つぎに、第２の出湯口１５と出湯切換手段１６の役割を説明する。一般の出湯形態において温度成層２６を形成して貯湯タンク内１０に水を沸き上げる場合に、熱交換手段２８で吸熱され冷やされた中間温度（図示せず例えば５０℃程度）の残湯は、高温部２４（例えば８０℃）と低温部２５（給水温度）の間に挟まれて貯湯タンク１０の下部に移動するが、貯湯タンク１０全体を高温に沸き上げる前に給湯が始まると、高温部２４から出湯され中間温度の残湯はまた上部に移動し、いつまでも貯湯タンク１０内にとどまってしまい、全体貯湯熱量を低下させていた。
【００３３】
また、この中間温度の残湯が出湯によって貯湯タンク１０の上部に移動した場合に、熱交換手段２８の周辺温度が低下するために充分な浴槽水の追焚ができなくなってしまう。
【００３４】
さらに、この中間温度の残湯を加熱手段で沸き上げようとした場合には、水加熱用熱交換器３８に例えば５０℃程度の湯が流入し、ヒートポンプサイクルの高圧圧力が上昇するためにサイクル効率が低下するなどの課題があった。
【００３５】
以上の課題を出湯切換手段１６は、貯湯タンク１０からの出湯をする場合に、先に第２の出湯口１５から行い、貯湯タンク１０の下部の中間温度の残湯を先に出湯するので、第２の出湯口より下部の残湯が無くなるまで貯湯タンク上部の高温部の湯は使われない。したがって、熱交換手段２８周辺の温度は高温が保たれる。また次に沸き上げる場合に、水加熱用熱交換器３８には給水温度の水を加熱するのでサイクル効率を高い状態で維持できる。
【００３６】
（実施例２）
図２は、本発明の実施例２の給湯装置の構成図である。なお、実施例１の給湯装置と同一構造のものは同一符号を付与し、説明を省略する。図において、実施例１の構成と異なるところは、５０の熱交換手段で、これは熱交換器５１と、熱交換ポンプ５２と熱交換水路５３ａ、５３ｂで構成している。熱交換器５１は２層構造で熱交換水路５３ａからの湯と戻り管３１からの浴槽水２７との熱交換を行うもので、例えば湯と浴槽水２７がそれぞれ流水する金属パイプを密着させたものを用いる。熱交換ポンプ５２は、熱交換水路５３ａに設けて浴水ポンプ３２と連動して駆動する循環ポンプで、貯湯タンク１０の湯を熱交換器５１に通水する。熱交換水路５３ａ、５３ｂは貯湯タンク１０上部と熱交換器５１を接続するものである。
【００３７】
また、２９の浴水循環手段は、実施例１同様の構成であるが、熱交換手段５０と浴槽１１の間で浴水２７を循環するようになっている。実施例２は熱交換手段５０が貯湯タンク１０の湯側も強制循環の構成になっているために熱伝達率が高いので、熱交換器を小さくできる。また、貯湯タンク１０の外側に熱交換器が構成されるので、貯湯タンクを製造しやすくコストが下げられる。
【００３８】
なお、実施例では加熱手段に超臨界ヒートポンプサイクルを用いたが、もちろん通常のヒートポンプサイクルでも良いし、一般のヒータや燃焼機でも同様の効果が得られる。
【００３９】
以上の説明から明らかなように本発明の給湯装置によれば、次の効果を奏する。
（１）貯湯タンクの湯が浴槽への湯張りやシャワー等に使われて残湯が少なくなっても、加熱制御手段により貯湯タンク内の温度成層を上部から下部に移動するように沸き増しできるので、熱交換手段の吸熱に必要な高温の湯を必要な量沸き増しできる。したがって、熱交換手段の吸熱量が増し浴槽水の追焚きが素早くできる。
（２）貯湯タンクの残湯が少なく熱交換手段近傍の温度が低い状態でもすぐに高温に沸き増しできるので、浴槽水の追焚きも素早くできる。
（３）熱交換手段の周辺の貯湯温度を所定温度以上に素早く加熱できるので、熱交換手段近傍の温度低下による浴槽水の追焚き熱量不足を未然に防止できる。
（４）第２の出湯口から先に出湯するので、中間温度の残湯を先に出湯するので、第２の出湯口より下部の残湯が無くなるまで貯湯タンク上部の高温部の湯は使われないで、高温の貯湯が素早くでき、貯湯タンク全体の貯湯熱量が大きくできる。
（５）第２の出湯口より下部の残湯が無くなるまで貯湯タンク上部の高温部の湯は使われないで、この第２の出湯口より上部の熱交換手段近傍は高温に維持でき、浴槽水の追焚きを行う際に熱交換効率の高く素早い追焚きができる。
（６）第２の出湯口より下部の残湯が少なくなった場合に自動的に第１の出湯口から出湯するように切換えられるので、使用者は出湯口の切換を意識することなく自然に給湯できる。
（７）貯湯タンクに温度成層を形成し、低温部の水を超臨界ヒートポンプサイクルで加熱することにより、サイクル効率が向上し、省動力運転を行うことができる。
【００４０】
【発明の効果】
以上のように、請求項１〜７に記載の発明によれば、貯湯式温水器の貯湯熱を効率よく利用して浴槽水の追焚きや保温を行う給湯装置を提供することができる。
【図面の簡単な説明】
【図１】本発明の実施例１における給湯装置の構成図
【図２】本発明の同実施例２における給湯装置の構成図
【図３】従来の給湯装置の構成図
【符号の説明】
１０貯湯タンク
１１浴槽
１２加熱手段
１４第１の出湯口
１５第２の出湯口
１６出湯切換手段
１８残湯量センサ
１９第１の取水口
２０供給口
２１湯水循環手段
２３加熱制御手段
２８熱交換手段
３３第２の取水手段
３４取水切換手段[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hot water supply apparatus that can heat a bathtub using hot water stored in a hot water heater.
[0002]
[Prior art]
There has been a hot water supply apparatus as described in Japanese Patent Application Laid-Open No. 11-83156 as a means for replenishing bath water or keeping warm using the hot water stored in a hot water heater. As shown in FIG. 3, the hot water supply apparatus includes a hot water storage tank 1 having heaters 2 and 3 at the upper and lower portions, a heat exchanger 4 provided at the upper portion of the hot water storage tank 1, and a space between the heat exchanger 4 and the bathtub 5. The hot water supply device is provided with a circulation path 6 for chasing and keeping warm of the bathtub 5, and the heat exchanger 4 exchanges heat between the bathtub water in the circulation path 6 and the hot water in the hot water storage tank 1. The amount of heat necessary for replenishing bathtub water in a general household is considered to be about 10 kW because of the desire to immediately raise the temperature during bathing. On the other hand, if the heat of the hot water storage tank 1 is used to replenish bathtub water, a sufficiently satisfactory amount of heat can be obtained. However, since the hot water in the hot water storage tank 1 is used for filling the bathtub 5 or showering, the remaining hot water in the hot water storage tank 1 is not constant. Become. In addition, since the remaining hot water temperature decreases when bath water is reheated, the amount of heat exchanged decreases as the number of reheating is repeated, and the time required for reheating is reduced, and the remaining hot water temperature approaches the bath water temperature. The end will not be able to memorialize.
[0003]
In order to solve this problem, Japanese Patent Laid-Open No. 11-83156 discloses that the upper heater 2 in the hot water storage tank 1 is energized when bathtub water is circulating in the circulation path 6. In addition, the temperature of the hot water in the upper part of the hot water storage tank 1 is detected before heat exchange, and after the heat exchange, the upper heater 2 is energized to return the hot water temperature in the upper part of the hot water storage tank 1 to the original temperature.
[0004]
However, since the attachment position of the upper heater 2 to the hot water storage tank 1 is fixed and the heater capacity is limited, for example, when the capacity of the hot water storage tank 1 heated by the heater 2 is large (the heater 2 is provided at a low position). In this case, the hot water cannot be quickly returned to the original temperature. Further, when the capacity of the hot water storage tank 1 heated by the heater 2 is small (when the heater 2 is provided at a high position), the hot water temperature rises quickly, but the temperature drop due to reheating is quick, and the bath water is completely cooled. There was a problem that it would be impossible to remedy if it was closed.
[0005]
The amount of heat required to refill the bath water varies depending on the size of the bathtub, the frequency of bathing, the temperature, etc., and the amount of heat required for it varies, but in the conventional example, the remaining hot water in the hot water storage tank 1 has decreased. In this case, since the position of the heater 2 for securing the amount of heat necessary for replenishing the bath water is fixed, there is a problem that the amount of heat is excessive or insufficient. In particular, when heat is used by installing a heat exchanger in the hot water storage tank, heat exchange cannot be sufficiently performed unless the hot water temperature of the hot water storage tank is maintained at a high temperature. Therefore, if high-temperature hot water is boiled up unnecessarily, there is a problem that heat dissipation loss increases.
[0006]
[Problems to be solved by the invention]
The present invention solves the above-described conventional problems, and an object thereof is to provide a hot water supply apparatus that replenishes bath water and keeps warm by efficiently using hot water stored in a hot water heater.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the hot water supply apparatus of the present invention includes a hot water storage tank, heating means for heating hot water in the hot water storage tank, and heat exchange means for exchanging heat with hot water in the hot water storage tank. A first hot water outlet provided at an upper portion of the hot water storage tank, a second hot water outlet provided at a central portion of the hot water storage tank, and a remaining hot water amount sensor for detecting a remaining hot water amount at an intermediate temperature in the hot water storage tank. If the amount of remaining hot water at the intermediate temperature detected by the remaining hot water amount sensor is equal to or greater than a predetermined amount, the remaining hot water at the intermediate temperature is discharged from the second outlet port, and the amount of remaining hot water at the intermediate temperature detected by the remaining hot water amount sensor is If it is less than the predetermined amount, the hot water is discharged from the first hot water outlet.
[0008]
According to the above invention, since the hot water is discharged first from the second hot water outlet, the hot water in the high temperature portion above the hot water storage tank is discharged until the remaining hot water at the intermediate temperature is discharged first and there is no remaining hot water below the second hot water outlet. Is not used, hot hot water can be stored quickly, and the amount of hot water stored in the entire hot water tank can be increased.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The invention described in claim 1 is provided in a hot water storage tank, a heating means for heating hot water in the hot water storage tank, a heat exchange means for exchanging heat with the hot water in the hot water storage tank, and an upper part of the hot water storage tank. A first hot water outlet, a second hot water outlet provided in a central portion of the hot water storage tank, and a remaining hot water amount sensor for detecting a remaining hot water amount at an intermediate temperature in the hot water storage tank, and an intermediate detected by the remaining hot water amount sensor. If the amount of remaining hot water at a temperature is equal to or greater than a predetermined amount, the remaining hot water at an intermediate temperature is discharged from the second outlet, and if the amount of remaining hot water at the intermediate temperature detected by the remaining hot water amount sensor is less than a predetermined amount, the second The hot water is discharged from the 1 hot water outlet .
[0010]
Therefore, since the hot water is discharged first from the second hot water outlet, the hot water at the upper part of the hot water storage tank is not used until the remaining hot water at the intermediate temperature is discharged first, and there is no remaining hot water at the lower part from the second hot water outlet. Thus, hot hot water can be stored quickly, and the amount of hot water stored in the entire hot water storage tank can be increased.
[0011]
In addition, when the remaining hot water at the lower part of the second hot water outlet becomes less, the hot water is automatically switched from the first hot water outlet so that the user can naturally supply hot water without being aware of the switching of the hot water outlet. it can.
[0012]
In the invention according to claim 2, the heat exchanging means according to claim 1 is provided above the second outlet. Thus, the hot water in the upper part of the hot water storage tank is not used until there is no remaining hot water below the second hot water outlet, and the vicinity of the heat exchange means above the second hot water outlet can be maintained at a high temperature. When water is reclaimed, heat exchange efficiency is high and quick requisition is possible.
[0013]
According to a third aspect of the present invention, there is provided the hot water supply apparatus according to the second aspect, wherein the first intake port provided at the bottom of the hot water storage tank, the first intake port and the lower side than the first heat intake unit. And a water intake switching means for switching between the first water intake port and the second water intake port. Accordingly, when boiling the entire hot water storage tank, it takes time to reheat the remaining hot water in the hot water storage tank by removing water from the first water intake port, heating it with the heating means, and then returning it to the supply port. However, the hot part reaches the bottom of the hot water tank, and the entire hot water tank is filled with the hot part. On the other hand, if water is taken out from the second intake port by the switching means, the remaining hot water in the hot water storage tank reaches the second intake port at an early stage and is reheated, so that the upper part from the second intake port is heated to a high temperature. You can raise it quickly. Therefore, even if the hot water in the hot water storage tank is small and the temperature in the vicinity of the heat exchange means is low, the water can be quickly heated to a high temperature, so that the bath water can be replenished quickly.
[0014]
The invention described in claim 4 is the hot water supply apparatus according to claim 2, further comprising temperature detecting means for detecting the hot water temperature of the hot water storage tank above the second intake port and below the heat exchange means, The intake switching means switches from the first intake to the second intake when the temperature detecting means detects a predetermined temperature or lower. Thereby, the hot water storage temperature around the heat exchanging means can be quickly heated to a predetermined temperature or higher, so that it is possible to prevent an insufficient amount of reheating heat from the bathtub water due to a temperature drop in the vicinity of the heat exchanging means.
[0015]
In the invention of claim 5 , the heating means is a supercritical heat pump cycle in which the pressure of the refrigerant becomes equal to or higher than the critical pressure, and the flowing water by the hot water circulation means is heated by the refrigerant whose pressure is increased to the critical pressure or higher. It is composed. In the supercritical heat pump cycle, when the flowing water of the hot water circulation means is heated to a high temperature (for example, 90 ° C.), the lower the flowing water temperature before heating, the lower the high-pressure pressure, and thus the cycle efficiency (COP = heating capacity / consumption). Power). Therefore, by forming temperature stratification in the hot water storage tank and heating the water in the low temperature part with a supercritical heat pump cycle, cycle efficiency can be improved and power saving operation can be performed. Further, if the remaining hot water at the intermediate temperature is discharged from the hot water supply, only the water in the low temperature part is heated in the supercritical heat pump cycle, so that the efficiency is further improved.
[0016]
In addition to the above configuration , the present invention is provided with a remaining hot water amount sensor in the hot water storage tank, and the switching means has a hot water outlet from the first hot water outlet when the remaining hot water below the second hot water outlet is reduced to a predetermined amount or less. It is made to switch so that it may do. According to the present invention, when the remaining hot water in the lower part of the second hot water outlet is reduced, the hot water is automatically switched from the first hot water outlet so that the user is aware of the switching of the hot water outlet. There is no natural hot water supply.
[0017]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
[0018]
(Example 1)
FIG. 1 is a configuration diagram of a hot water supply apparatus according to Embodiment 1 of the present invention. This embodiment is a hot water supply device for general households, which mainly stores hot water for hot water using cheap midnight power, and comprises a hot water storage tank 10, a bathtub 11, and a heating means 12 constituted by a heat pump cycle. Composed.
[0019]
Hot water is supplied from a water supply port 13 at the bottom of the hot water storage tank 10 and discharged from a first hot water outlet 14 provided in the upper part of the hot water storage tank 10 or a second hot water outlet 15 provided in the center. A hot water switching means 16 comprises a three-way valve 16a for switching between the first hot water outlet 14 and the second hot water outlet 15 and a hot water switching control means 17. The hot water switching control means 17 detects the remaining hot water amount in the hot water storage tank 10 from the remaining hot water amount sensors 18a, 18b, 18c, and discharges hot water from the second hot water outlet 15 if there is residual hot water in each remaining hot water amount sensor 18a, 18b, 18c. When the three-way valve 16a is controlled in such a manner that the remaining hot water amount sensor 18a immediately below the second hot water outlet 15 detects that no hot water has been used, the three-way valve 16a is discharged from the first hot water outlet 14. Is switched and controlled. As a result, first, the hot water in the hot water storage tank 10 is discharged from the lower part of the second hot water outlet 15 and then from the upper part.
[0020]
Boiling in the hot water storage tank 10 takes out water from a first water intake 19 provided at the bottom of the hot water storage tank 10 and returns it from a supply port 20 at the upper part of the hot water storage tank 10, and the hot water circulation means 21. The heating means 12 for heating the running water is used. Specifically, it is provided in the vicinity of the outlet 21a of the heating means 12, and the detection value of the heating sensor 21b for detecting the heating temperature of the flowing water is input, and the boiling pump 22 of the hot water circulating means 21 and the heat pump cycle of the heating means 12 are input. Is controlled by the heating control means 23 so that hot (for example, 90 ° C.) hot water is returned to the supply port 20. Thereby, the inside of the hot water storage tank 10 is divided into a high temperature part 24 and a low temperature part 25, and a temperature stratification 26 is formed. The temperature stratification 26 moves below the hot water storage tank 10 according to the boiling operation, and finally the entire hot water storage tank 10 is entirely inside. It becomes the high temperature part 24. The boiling of the entire hot water storage tank 10 is set in advance during the main energization time zone (for example, from 23:00 when the electricity bill for the hourly lamp is low to 7 in the next morning). In a time zone other than the main energizing time zone, a heating operation is appropriately performed according to the remaining hot water in the hot water storage tank 10.
[0021]
When the bath water 27 in the bathtub 11 is kept warm or reheated, heat is absorbed by the heat exchanging means 28 provided in the upper part of the hot water storage tank 10, and the heat from the heat exchanging means 28 is transferred through the bath water circulating means 29. To supply.
[0022]
The heat exchanging means 28 is a heat exchanger in which a metal pipe is formed in a coil shape and disposed in the hot water storage tank 10, and the bath water flowing in the metal pipe and the hot water in the hot water storage tank 10 exchange heat.
[0023]
The bath water circulation means 29 is composed of an outgoing pipe 30, which connects the bathtub 11 and the heat exchange means 28, a return pipe 31, and a bath water pump 32 provided in the return pipe 31. The bath water circulation means 29 is a heat exchange means. It is sent to 28 and acts to return the heated bathtub water to the bathtub 11.
[0024]
Reference numeral 33 denotes a second water intake port for taking out water from the hot water storage tank 10 from a high position, and is arranged above the first water intake port 19 and below the heat exchange means 28. And when the intake switching means 34 which switches the 1st intake port 19 and the 2nd intake port 33 is provided and only the upper part of the hot water storage tank 10 wants to boil, the hot water circulation means 21 supplies water from the 2nd intake port 33. The water taken out and heated to a high temperature by the heating means 12 is returned to the supply port 20.
[0025]
35 is a heating switching control means, 36 is a temperature detection means for detecting the hot water temperature in the hot water storage tank 10 above the second water intake port 33 and below the heat exchange means 28, and the heating switching control means 35 is a temperature detection means. When the detected temperature of the means 36 becomes a predetermined temperature (for example, 60 ° C.) or less, the intake switching means 34 is driven to switch so that water can be taken from the second intake 33, and the heating control means 23 is operated to supply hot water. The circulation means 21 is activated to heat the hot water at the top of the second water intake 33. That is, when the remaining hot water in the upper part of the hot water storage tank 10 is reduced, only the area above the second water intake 33 can be heated, so that the temperature rises faster.
[0026]
The heating means 12 uses a supercritical heat pump cycle in which, for example, carbon dioxide gas is used as a refrigerant, so that the refrigerant pressure on the high pressure side becomes equal to or higher than the critical pressure of the refrigerant. This heat pump cycle is composed of functional parts such as a compressor 37, a water heating heat exchanger 38, an expansion valve 39, and an evaporator 40. The compressor 37 is driven by a built-in electric motor (not shown), and compresses and sucks the sucked refrigerant to a critical pressure.
[0027]
The water heating heat exchanger 38 exchanges heat between the refrigerant and the water flowing through the hot water circulation means 21. For example, the refrigerant passage 41 through which the refrigerant flows and the flowing water passage 42 through which the water flows are provided in a double pipe structure. And it is a counterflow type heat exchanger comprised so that the flow direction of a refrigerant | coolant and the flow direction of flowing water may oppose. The expansion valve 39 decompresses the refrigerant flowing out of the water heating heat exchanger 38 and supplies it to the evaporator 40. The evaporator 40 evaporates the refrigerant decompressed by the expansion valve 39 by heat exchange with the atmosphere.
[0028]
43 is a mixing valve that mixes hot water discharged from the three-way valve 16a and tap water from the water supply pipe 44, and feeds back a detection value of the mixing temperature sensor 45 that detects the mixing temperature to a predetermined temperature (for example, 40 ° C.). Are mixed and sent to the hot water discharge pipe 46. The hot water pipe 46 is connected to a faucet 47 or a shower (not shown).
[0029]
48 is an open / close valve provided in a pouring pipe 49 connecting the outlet pipe 46 and the outgoing pipe 30. When the hot water is filled in the bathtub 11 or hot water is poured, the mixing valve 48 is opened.
[0030]
As described above, according to the configuration of the first embodiment, even if the hot water in the hot water storage tank 10 boiled in the main energizing time zone at midnight is used for filling the bathtub 11 or showering, the remaining hot water is reduced. Since the temperature stratification 26 in the hot water storage tank 10 can be increased by the means 23 so as to move from the upper part to the lower part, the hot water necessary for the heat exchange of the heat exchange means 28 can be increased by the required amount. Therefore, the heat absorption amount of the heat exchanging means 28 is increased, and the bath water 27 can be chased quickly.
[0031]
Further, when the temperature detecting means 36 becomes a predetermined temperature (for example, 60 ° C.) or less, water is taken in from the second water intake 33 and the hot water circulation means 21 is activated, and the hot water from the second water intake 33 is discharged. Since heating is performed, the hot water storage temperature around the heat exchanging means 28 can be quickly heated. Therefore, even if the remaining hot water in the hot water storage tank 10 is reduced, high-temperature hot water can be immediately supplied to the vicinity of the heat exchanging means 28, and an insufficient amount of reheating heat of the bathtub water due to a temperature drop can be prevented.
[0032]
Next, the roles of the second hot water outlet 15 and the hot water switching means 16 will be described. When the temperature stratification 26 is formed in a general hot water form and water is boiled in the hot water storage tank 10, the remaining hot water having an intermediate temperature (not shown, for example, about 50 ° C.) absorbed by the heat exchange means 28 is cooled. It is sandwiched between the high temperature part 24 (for example, 80 ° C.) and the low temperature part 25 (water supply temperature) and moves to the lower part of the hot water storage tank 10. The remaining hot water discharged from 24 moved to the upper part again and stayed in the hot water storage tank 10 indefinitely, reducing the total amount of stored hot water.
[0033]
Further, when the remaining hot water at the intermediate temperature is moved to the upper part of the hot water storage tank 10 by the outgoing hot water, the ambient temperature of the heat exchanging means 28 is lowered, so that sufficient bath water cannot be replenished.
[0034]
Further, when the remaining hot water at the intermediate temperature is to be boiled by the heating means, hot water of, for example, about 50 ° C. flows into the water heating heat exchanger 38, and the high pressure of the heat pump cycle rises. There were problems such as reduced efficiency.
[0035]
When the hot water switching means 16 discharges hot water from the hot water storage tank 10, the hot water switching means 16 performs the hot water from the second hot water outlet 15 first, and the hot water at the intermediate temperature in the lower part of the hot water storage tank 10 is discharged first. The hot water at the upper part of the hot water storage tank is not used until there is no remaining hot water below the second outlet. Therefore, the temperature around the heat exchange means 28 is kept high. When the water is subsequently boiled, the water heating heat exchanger 38 is heated with water at the feed water temperature, so that the cycle efficiency can be maintained at a high level.
[0036]
(Example 2)
FIG. 2 is a configuration diagram of a hot water supply apparatus according to Embodiment 2 of the present invention. In addition, the thing of the same structure as the hot water supply apparatus of Example 1 gives the same code | symbol, and abbreviate | omits description. In the figure, the difference from the configuration of the first embodiment is 50 heat exchange means, which is constituted by a heat exchanger 51, a heat exchange pump 52, and heat exchange water channels 53a and 53b. The heat exchanger 51 performs heat exchange between the hot water from the heat exchange water channel 53a and the bathtub water 27 from the return pipe 31 with a two-layer structure. For example, the metal pipes through which the hot water and the bathtub water 27 flow are in close contact with each other. Use things. The heat exchange pump 52 is a circulation pump that is provided in the heat exchange water channel 53 a and is driven in conjunction with the bath water pump 32, and allows the hot water in the hot water storage tank 10 to pass through the heat exchanger 51. The heat exchange channels 53a and 53b connect the upper part of the hot water storage tank 10 and the heat exchanger 51.
[0037]
The 29 bath water circulation means has the same configuration as that of the first embodiment, but the bath water 27 is circulated between the heat exchange means 50 and the bathtub 11. In the second embodiment, since the heat exchange means 50 has a forced circulation configuration on the hot water side of the hot water storage tank 10, the heat transfer rate is high, so the heat exchanger can be made small. Further, since the heat exchanger is configured outside the hot water storage tank 10, it is easy to manufacture the hot water storage tank, and the cost is reduced.
[0038]
In the embodiment, a supercritical heat pump cycle is used as the heating means. However, a normal heat pump cycle may be used as a matter of course, and a similar effect can be obtained with a general heater or combustor.
[0039]
As apparent from the above description, the hot water supply apparatus of the present invention has the following effects.
(1) Even if the hot water in the hot water storage tank is used for filling the bathtub or showering and the remaining hot water is low, the temperature control in the hot water storage tank can be heated to move from the upper part to the lower part by the heating control means. Therefore, the necessary amount of hot water required for heat absorption of the heat exchange means can be increased. Therefore, the amount of heat absorbed by the heat exchanging means is increased, and the bath water can be replenished quickly.
(2) Since the hot water in the hot water storage tank is small and the temperature in the vicinity of the heat exchanging means is low, it can be quickly heated to a high temperature, so that the bath water can be quickly replenished.
(3) Since the hot water storage temperature around the heat exchanging means can be quickly heated to a predetermined temperature or higher, it is possible to prevent an insufficient amount of reheating heat from the bathtub water due to a temperature drop in the vicinity of the heat exchanging means.
(4) Since the hot water is discharged first from the second hot water outlet, the hot water in the upper part of the hot water storage tank is used until there is no remaining hot water at the lower part of the hot water outlet. It is possible to quickly store hot water at a high temperature and increase the amount of hot water stored in the entire hot water storage tank.
(5) The hot water at the upper part of the hot water storage tank is not used until there is no remaining hot water below the second hot water outlet, and the vicinity of the heat exchanging means above the second hot water outlet can be maintained at a high temperature. When water is reclaimed, heat exchange efficiency is high and quick requisition is possible.
(6) Since the hot water is automatically switched from the first hot water outlet when the remaining hot water in the lower part of the second hot water outlet is reduced, the user can naturally switch without having to be aware of the switching of the hot water outlet. Hot water can be supplied.
(7) By forming temperature stratification in the hot water storage tank and heating the water in the low temperature part with a supercritical heat pump cycle, cycle efficiency is improved and power saving operation can be performed.
[0040]
【The invention's effect】
As described above, according to the first to seventh aspects of the present invention, it is possible to provide a hot water supply device that efficiently uses the hot water stored in the hot water storage hot water heater to recharge and keep warm the bathtub water.
[Brief description of the drawings]
FIG. 1 is a block diagram of a hot water supply apparatus according to a first embodiment of the present invention. FIG. 2 is a block diagram of a hot water supply apparatus according to the second embodiment of the present invention.
DESCRIPTION OF SYMBOLS 10 Hot water storage tank 11 Bath 12 Heating means 14 1st hot water outlet 15 2nd hot water outlet 16 Hot water switching means 18 Remaining hot water amount sensor 19 First intake 20 Supply port 21 Hot water circulation means 23 Heating control means 28 Heat exchange means 33 Second water intake means 34 Water intake switching means

Claims

A hot water storage tank; heating means for heating hot water in the hot water storage tank; heat exchanging means for exchanging heat with hot water in the hot water storage tank; a first hot water outlet provided at an upper part of the hot water storage tank; A second hot water outlet provided in the center of the tank; and a remaining hot water amount sensor for detecting a remaining hot water amount at an intermediate temperature in the hot water storage tank, wherein the remaining hot water amount at the intermediate temperature detected by the remaining hot water amount sensor is a predetermined amount or more. If there is, the hot water supply device which discharges hot water at an intermediate temperature from the second hot water outlet and discharges hot water from the first hot water outlet if the remaining hot water amount at the intermediate temperature detected by the residual hot water sensor is equal to or less than a predetermined amount. .

Heat exchange means is a hot water supply apparatus according to claim 1, wherein provided in the upper than the second outflow position.

A first intake port provided at the bottom of the hot water storage tank; a second intake port provided above the first intake port and below the heat exchange means; the first intake port and the second intake port. The hot water supply apparatus according to claim 2, further comprising: a water intake switching unit that switches between the water intake and the water intake.

Temperature detecting means for detecting the hot water temperature of the hot water storage tank above the second water intake and below the heat exchanging means, and the water intake switching means is the first when the temperature detecting means detects a predetermined temperature or less. The hot water supply device according to claim 3, wherein the water intake is switched from the water intake to the second water intake.

Heating means is a supercritical heat pump cycle in which the pressure of the refrigerant becomes critical pressure or higher, according to any one of claims 1-4 for heating the flowing water by the hot water circulating means by pressurized refrigerant above the critical pressure Water heater.