JP4092619B2

JP4092619B2 - Negative pressure breaker

Info

Publication number: JP4092619B2
Application number: JP2002041979A
Authority: JP
Inventors: 誠濱田; 克博藤原; 亮二大内; 秀仁市丸; 晶吉田; 恒男船引; 学清水; 逸夫永井; 直人小針
Original assignee: Noritz Corp
Current assignee: Noritz Corp
Priority date: 2002-02-19
Filing date: 2002-02-19
Publication date: 2008-05-28
Anticipated expiration: 2022-02-19
Also published as: JP2003235743A

Description

【０００１】
【発明の属する技術分野】
本発明は、上水道から直接に又は受水槽からポンプ圧送により間接に供給される浄水が分岐路を通して大気開放の貯槽へ直接又は間接に注水可能とされたものにおいて、浄水供給路側での負圧発生の際にその負圧を破壊（解消）して貯槽側から浄水供給路側への逆流発生を阻止するために用いられる負圧破壊装置に関する。
【０００２】
【従来の技術】
従来、この種の負圧破壊装置として、例えば給湯装置に設置されたものが知られている。この給湯装置は、浄水が給水される浄水供給路としての給湯回路又は給水回路により台所等の給湯栓又は給水栓に対し給湯又は給水する一方、浴槽や洗濯槽等の大気開放する貯槽へ上記給湯回路又は給水回路から分岐した注湯路（分岐路）又は注水路（分岐路）を通して湯又は水を直接に又は間接に注湯又は注水し得るように構成されており、上記注湯路や注水路に対し負圧破壊装置が介装されている。このような負圧破壊装置は、水道水（浄水）が給水される給湯回路又は給水回路内において例えば水道水供給側の断水あるいは停電等に起因して負圧が生じた場合に、浴槽や洗濯槽等の貯槽の湯水が逆流して給湯回路内又は給水回路内、つまり浄水供給路内に流入する事態の発生を阻止するために設けられるものであり、上記負圧破壊装置により給湯回路又は給水回路と上記貯槽との間を注湯・注水及び遮断の切換を可能にしつつも縁切り可能な状態に接続するようにしている。つまり、浄水が充満している給湯回路又は給水回路に対し雑水である浴槽や洗濯槽内の湯水が逆流して混入してしまう事態の発生を防止するために負圧破壊装置が介装されている。この逆流防止性能を実現するための従来の負圧破壊装置を図８に示す給湯装置１０に設置された例に基づいて説明する。
【０００３】
この給湯装置１０は貯槽として浴槽３に対し注湯し得るようにした給湯器付き風呂釜を例にしたものである。すなわち、給湯回路２の給湯側に介装された流量調整弁（水量サーボ弁）３０の下流から注湯路５０が分岐され、この注湯路５０を介して給湯回路２と、浴槽３に連通された追い焚き循環回路４とが連通接続されて浴槽３に対し注湯又は注水（以下、両者をまとめて単に「注湯」という）が可能とされている。そして、この注湯路５０に対し、上流側からバキュームブレーカ（負圧破壊弁）５２、注湯電磁弁５３及び２段の逆止弁５４，５５の順で配設された負圧破壊装置５を介装させている。なお、符号５１は注湯流量を検出するための注湯流量センサである。
【０００４】
上記のバキュームブレーカ５２は回路内に所定の負圧が生じたときに外気（エア）を吸い込んで負圧状態を解消（破壊）するもの、注湯電磁弁５３は注湯路５０を開閉切換えして注湯及び遮断の切換を行うもの、また、２段の逆止弁５４，５５は給水圧を受けて注湯方向（順方向）への流通を許容しつつ給水圧の解消により閉弁状態にバネ復帰して逆方向への流通を阻止するものである。
【０００５】
より詳しくは、上記バキュームブレーカ５２は、弁体がバネにより弁座に押し付けられた状態で常時は注湯路５０内の給水圧により閉状態に維持される一方、回路内に所定の負圧が作用したときには上記弁体がバネに抗して開きエアを回路内に吸い込んで上記負圧を解消するようになっている。つまり、上記バキュームブレーカ５２は給水圧を受けて閉弁状態に維持され、負圧を受けて開弁するという圧力バランス型のものにより構成され、上記バネは所定の負圧（設定吸気作動圧）の発生により吸気作動し始めるように初期付勢力を弁体に付与するものである。
【０００６】
また、上記注湯電磁弁５３は、パイロット式のダイヤフラム弁により構成され給湯回路２側の給水圧により閉弁状態に維持されるようになっている。つまり、開閉作動時に比較的高い給水圧を受けた状態でも比較的軽い作動力により開弁もしくは閉弁作動させることができ、かつ、その閉弁状態を確実に維持し得るようになっている。すなわち、弁体である可撓性ダイヤフラム弁を挟んで一側にダイヤフラム室が区画形成される一方、他側において筒状の弁座により区画されて外周側が上記給湯回路２と連通され、内周側が浴槽３側と連通されている。そして、上記弁座の先端にダイヤフラム弁が押し付けられることにより給湯回路２側と浴槽３側とを遮断した状態、つまり閉弁状態になり、この閉弁状態においてはブリード孔を通して給湯回路２側から給水圧がダイヤフラム室にブリードインされ、この給水圧がダイヤフラム弁に対し閉弁維持圧として作用するようになっている。従って、給水圧が高圧であればある程、より高い圧力で閉弁側に押し付けられて高い閉シール性能を発揮する。一方、注湯時には電磁石に通電することによりダイヤフラム弁中央のセンター孔を開いてダイヤフラム室と弁座内周側（浴槽３側）とを連通させてダイヤフラム弁を開弁させるようになっている。
【０００７】
ここで、上記の負圧が生じる場合としては、本来は給水圧（正圧）が作用している給湯回路側（給水一次側）において給水元である水道の断水や、受水槽等から各集合住宅（マンション等）の上階へポンプ圧送している場合に停電によるポンプ停止等が発生することにより、給水一次側の圧力が低下して負圧を生じる場合がある。
【０００８】
【発明が解決しようとする課題】
ところで、上記のような負圧破壊装置１０において、注湯路５０の注湯又は遮断の切換えを行う開閉切換弁としてパイロット式のダイヤフラム弁により構成された注湯電磁弁５３が採用されている理由は、注湯回路２側の比較的高い給水圧と浴槽３側のほぼ大気圧状態との圧力差がある注湯路５０を注湯（連通）及び遮断の切換えを上記のかなり高い給水圧の作用下においても比較的軽い作動力で開閉作動させることができ、かつ、給水圧を利用して高い閉弁維持性能（閉シール性能）を発揮させることができるためである。
【０００９】
しかしながら、上記の注湯電磁弁５３の存在により負圧破壊装置１０全体のコンパクト化の要請に反する上に、ダイヤフラム弁部分において注湯路５０自体の通路径が絞られて（通路内断面積が狭くされて）しまい注湯時の圧損を招き吐出流量をあまり高くできないという問題が生じる。すなわち、上記ダイヤフラム弁としては、筒状弁座により区画された外周側連通部分（給湯回路２側）と、内周側連通部分（浴槽３側）との双方を覆って遮蔽し得るかなり大きい直径が必要となる。このため、注湯電磁弁５３自体がかなり大きいものにならざるを得ず、装置全体のコンパクト化を阻害することになる。加えて、上記の如く一つのダイヤフラム弁により外周側及び内周側の両連通部分を覆い、このダイヤフラム弁に対し給湯回路２側及び浴槽３側の双方からの通路を連通させる必要上、各通路径又は通路内断面を他の部分よりも小さくせざるを得ず、このため、流通抵抗増や注湯時の吐出流量（注湯流量）の制約を招くことになる。
【００１０】
加えて、注湯電磁弁５３がダイヤフラム弁を備えて構成されているが故に、上流側からの脈動の影響を受け易くなるという不都合もある。すなわち、給湯栓２６ａ，２６ｂの急開閉操作に起因して給湯回路２側において発生した脈動が伝搬し、上記注湯電磁弁５３のダイヤフラム弁をバウンドさせるおそれがある。そして、このバウンドの発生に伴い上流側から下流側へ漏水が生じることになる。
【００１１】
その一方、上記の注湯電磁弁５３においては、非通電時には閉弁状態にバネ復帰するというノーマルクローズタイプとすることで、開弁させた注湯状態で停電が発生しても、その停電により自動的に閉弁させ得るという利点もある。
【００１２】
このため、上記ダイヤフラム弁を採用した注湯電磁弁５３の代わりに、弁体を例えばモータ等により強制的に開閉切換えし得る開閉切換弁を採用することも考えられるが、このような開閉切換弁を採用する場合には停電時対策も考慮する必要がある。
【００１３】
また、負圧破壊装置５を上記の如き注湯電磁弁５３等を採用して構成した場合には、各弁が正常に作動すればよいものの、注湯電磁弁５３や逆止弁５４，５５に故障等の異常が発生した場合には給水一次側での負圧発生により浴槽３側からの逆流入が生じてしまうおそれがある。すなわち、上記注湯電磁弁５３や逆止弁５４，５５に故障又は異物噛み込み等の原因により本来閉止すべきとき（例えば注湯完了したときの定常状態のとき）に完全には閉止せずに開いたままの閉作動異常が生じた場合、給水一次側が断水等により負圧状態に陥ると、その負圧が浴槽３側まで及ぶことになる。この負圧発生の際にはバキュームブレーカ５２が開きエアを吸い込み始めて負圧を破壊することにはなるものの、このバキュームブレーカ５２は上記の如く圧力バランス型であるため、そのエア吸い込み作動の開始は負圧発生時点に対し遅れがあり、その間に負圧が上記閉作動異常状態の注湯電磁弁５３や逆止弁５４，５５を通過して浴槽３側に及んでしまい、逆流発生のおそれを招くことになる。
【００１４】
これに対処すべく、注湯電磁弁の下流側位置の注湯路内に、定常状態においては強制的に開弁状態にして大気と連通させる一方、注湯時には閉弁状態に変換させ得るモータ駆動式の弁手段を介装させることにより、フェイルセーフを図ることが考えられる。つまり、強制的に開閉切換えさせ得るバキュームブレーカを注湯電磁弁の下流側位置に配設するものである。しかし、特に水道水（浄水）が受水槽からポンプ圧送により高層住宅（マンション等）の上層階まで供給される場合において、停電発生に伴うポンプの停止によって負圧が発生したときには、上記のモータ駆動式の弁手段を介装させたとしても停電により所定の作動を行い得なくなれば、エア吸い込みによる負圧解消も行い得ずに逆流が生じてしまう結果になると考えられる。これに対し、停電対策のために、停電になっても上記のモータ駆動式の弁手段を強制的に開作動させるだけの予備電源（例えば大静電容量のコンデンサ）を予め搭載させることも考え得るが、そのような予備電源をも搭載するとなると装置全体のコストとして大幅な増加を招いてしまうことになる。すなわち、モータ駆動式の弁手段では、通常、モータの回転駆動により弁軸自体を回転させてその弁軸を進退作動させるものであるため、閉弁状態から開弁状態まで上記弁軸を回転駆動するにはかなりの回転量を要し、このような大回転量を発現し得る駆動用電力エネルギーが必要となる。
【００１５】
以上のような閉作動異常や停電に起因する逆流入発生のおそれ等の不都合は、注水接続対象が浴槽ではなくて給湯回路又は給水回路から貯槽としての洗濯槽に対し自動注湯可能に接続した場合にも同様に生じることになる。さらに、浄水が所定の給水圧に基づき供給される浄水供給路から分岐した分岐路を通して大気開放の貯槽が注水可能に接続されている場合にも、上記の如き逆流入発生のおそれ等の不都合が同様に生じ得る。そして、注水・注湯の対象が大気開放された貯槽であり、注湯・注水された貯槽内の湯水が入浴又は洗濯等に使用されて雑水扱いとなる場合には、逆流入発生を確実に防止する必要がある。
【００１６】
本発明は、以上のような事情に鑑みてなされたものであり、その目的とするところは、浄水供給路側から大気開放の貯槽に対し注水を可能としつつも負圧破壊による逆流発生を阻止しようとする負圧破壊装置において、上記貯槽側からの逆流入発生を大型化や注水抵抗増加を招くことなく確実に防止し得る負圧破壊装置を提供することにある。併せて、弁の閉作動異常もしくは停電等が生じたとしても上記逆流入発生を確実に防止し、しかも、それをコスト増を招くことなく実現し得ることも目的とする。
【００１７】
【課題を解決するための手段】
上記目的を達成するために、従来のダイヤフラム弁を有する開閉切換弁に代えて、モータ等の駆動手段により強制的に開閉切換えし得る開閉切換弁を採用しつつも、この開閉切換弁に対し開閉切換えの抵抗となる給水圧をキャンセルする圧力キャンセル弁を付設可能とすることにより、ダイヤフラム弁の採用に伴う不利益を解消しつつ比較的軽い駆動力により確実な注水又は遮断の切換えを実現するようにしたものである。
【００１８】
具体的には、請求項１に係る発明では、浄水が所定の給水圧を受けて供給される浄水供給路に対しこの浄水供給路から分岐する分岐路を通して大気開放の貯槽が注水可能に接続され、上記分岐路に介装されて上記浄水供給路と貯槽とを注水切換可能にしつつ負圧を破壊する負圧破壊装置を対象として、次の特定事項を備えることとした。すなわち、上記分岐路に介装されて注水又は遮断の開閉切換えを行う主開閉切換弁と、この主開閉切換弁の上流側に作用する上記浄水供給路側からの内圧を相殺する圧力キャンセル弁と、上記主開閉切換弁の下流側位置に介装されて注水又は遮断の開閉切換えを行う駆動式の副開閉切換弁と、この副開閉切換弁と上記主開閉切換弁との間の位置に連通した状態で配設されて大気側との連通又は遮断の開閉切換えを行う駆動式の負圧破壊弁と、上記主開閉切換弁及び圧力キャンセル弁がそれぞれ結合され進退駆動力を受けて上記主開閉切換弁の開閉切換えを行う弁軸とを備えることとした。
【００１９】
なお、上記の「大気開放の貯槽」とは、その底部に注水を受けて貯留される湯水が自由水面を形成し、この自由水面に大気圧が作用することになるような貯槽のことであり、「浄水供給路」としては例えば給湯回路から入浴用の湯張り（水張り）のための注湯を受ける浴槽、又は、上記給湯回路から洗濯用湯水の湯張り（水張り）のための注湯を受ける洗濯槽等が挙げられる（以下の各請求項においても同じ）。また、上記の主開閉切換弁の開閉切換えは、弁軸を進退方向の一側及び他側の双方共に積極的に駆動させて開弁及び閉弁の双方を駆動力により行われる場合と、例えば開弁切換えを弁軸の進退方向一側への駆動力により行い、進退方向他側へはその駆動力の解除により閉弁切換えを許容しつつその閉弁状態への復帰切換え自体はバネ復帰により行わせる場合とのいずれを採用するようにしてもよい。
【００２０】
上記請求項１によれば、弁軸が進退駆動力を受けて主開閉切換弁を開閉切換させる際に、その主開閉切換弁に作用して開閉切換えの抵抗となる浄水供給路側からの内圧が同じ弁軸に結合された圧力キャンセル弁にも主開閉切換弁と同様に作用して相殺されることになる。つまり、主開閉切換弁の開閉切換えの際に抵抗となる内圧がキャンセルされるため、開閉切換えのための進退駆動力は浄水供給路側からの給水圧に打ち勝つものではなくて単に主開閉切換弁の弁体を作動させるだけの軽い駆動力で済むことになる。このため、主開閉切換弁として従来のダイヤフラム弁を使用しなくても、弁体により通路を直接に開閉させる単純なタイプのものにより浄水供給路側からかなり高い給水圧が作用する分岐路の注水又は遮断の切換えを軽い駆動力で確実に行うことが可能になる。これにより、上記のダイヤフラム弁タイプのものを使用する場合に比べ、装置全体のコンパクト化が図られる上に上記分岐路の通路径を狭めることもなく流通抵抗の増大を招くこともない。しかも、ダイヤフラム弁のバウンド発生に伴う不都合発生も回避し得ることになる。
【００２１】
その上に、主開閉切換弁の下流側位置には駆動式とされて強制的に開弁切換えが可能な負圧破壊弁が配設されているため、主開閉切換弁を閉弁させて遮断状態にした定常状態において上記負圧破壊弁を強制的に開弁状態に切換えておくことにより、たとえ上記主開閉切換弁等の弁に異物噛み込み等により完全には閉じていない閉作動異常が生じたとしても、浄水供給路側が負圧になれば上記の開弁状態の負圧破壊弁からエアが即座に吸い込まれることになる。これにより、上記負圧が解消され、貯槽側から浄水供給路側への逆流入の発生も確実に阻止される。なお、上記の定常状態において、主開閉切換弁に閉作動異常がなく正常に閉弁切換えされていれば、浄水供給路側に負圧が発生したとしても、この主開閉切換弁において貯槽側とは確実に遮断されているため、貯槽側からの逆流が発生することもない。
【００２２】
上記の主開閉切換弁を高い給水圧が作用していても軽い駆動力により開閉切換えさせることができるということは、停電発生時の対策においても優れた意義を発揮する。すなわち、上記の主開閉切換弁を閉弁状態（定常状態）にする前に浄水供給路側が停電発生に起因して負圧状態に陥った場合の対策として、上記弁軸を進退駆動させて主開閉切換弁を閉弁切換えさせる分の駆動用電力を弁軸の駆動手段に供給するための予備電源を備えて、停電発生時には予備電源からの電源供給により上記弁軸を作動させて主開閉切換弁を閉弁させるようにした場合、その予備電源（例えば電解コンデンサあるいは一次電池もしくは二次電池）に要求される必要容量を極めて小さいものにすることが可能になる。
【００２３】
すなわち、上記の主開閉切換弁に対しては浄水供給路からの比較的高い給水圧が内圧として作用し、駆動手段の回転駆動により弁軸を進退作動させて上記の閉弁切換えを行おうとすると、上記給水圧による抵抗に起因してかなり高い作動トルクを要するものになる。これに対し、請求項１の場合には圧力キャンセル弁により上記主開閉切換弁に作用する抵抗がキャンセルされるため、主開閉切換弁の閉弁切換えに要する作動トルクが大幅に軽減されることになる。このため、停電時の定常状態への復帰切換えのための駆動用電力エネルギーを大幅に低減することが可能になり、従って、予備電源を搭載するにしてもその大幅な小容量化を図ることが可能になり、コストの大幅増大を招くことなく主開閉切換弁の閉弁切換えにより停電発生に起因する逆流入発生を阻止することが可能になる。
【００２４】
ここで、上記弁軸に進退駆動力を付与する構成としては、その弁軸の一端又は両端にシリンダ等の往復駆動力を発生する駆動手段を接続させたり、モータの回転駆動力を往復動に変換させてから上記弁軸に伝達させたり、あるいは、ボルト・ナットの如く弁軸自体をモータにより回転駆動させることにより進退させたりというように種々のものを採用し得るが、特に付与する進退駆動力としては比較的軽いもので済むため、例えば電磁石（電磁コイル）を用いた電磁式駆動手段により弁軸を押し又は引きするようにする他、次の構成を採用するようにしてもよい。
【００２５】
すなわち、上記請求項１において、上記弁軸に進退駆動力を付与する駆動手段を備え、上記駆動手段として、回転駆動力を回転作動軸に伝達してこの回転作動軸に対し結合されたカム部材を回転作動するものとし、上記弁軸として、上記回転作動軸に対し直交するよう配設し一端から上記カム部材の正逆一側回転により進退方向一側への押圧力を受けて主開閉切換弁を閉弁状態の定常状態から開弁状態の注水状態へ切換える一方、上記カム部材の正逆他側回転によりその押圧力が解除されると上記注水状態から定常状態へ戻しバネによりバネ復帰する構成とする（請求項２）。ここで、上記の「駆動手段」としては、電動モータ（例えばサーボモータもしくはステッピングモータ）を用いればよく、あるいは通電により制御される油圧モータ等を用いることも可能である。
【００２６】
この請求項２の場合には、圧力キャンセル弁による駆動手段の作動トルクの軽減化に加え、弁軸の進退作動をカム駆動としているため、停電時に定常状態への復帰切換えのための駆動手段の必要回転量を、弁軸自体の回転により進退作動させる場合と比べ大幅に減少させることが可能になる。例えば同一進退量を実現させる上で弁軸自体を回転させる場合の３１５度からカム部材を回転させる場合の１０〜２０度に回転量を大幅低減させ得る。これにより、上記の復帰切換えのための駆動用電力エネルギーの大幅低減化が図られるため、停電時対策として定常状態への復帰切換え用に電源供給するための予備電源を搭載する場合であっても、その予備電源の必要静電容量の大幅な小容量化を実現して大幅なコスト増を回避しつつ停電時の逆流発生を回避し得る。なお、上記の駆動手段と回転作動軸との間に減速機構を介装させるようにしてもよい。
【００２７】
請求項３に係る発明では、浄水が所定の給水圧を受けて供給される浄水供給路に対しこの浄水供給路から分岐する分岐路を通して大気開放の貯槽が注水可能に接続され、上記分岐路に介装されて上記浄水供給路と貯槽とを注水切換可能にしつつ負圧を破壊する負圧破壊装置を対象にして、次の特定事項を備えることとした。
【００２８】
すなわち、上記分岐路に介装されて注水又は遮断の開閉切換えを行う主開閉切換弁と、この主開閉切換弁の上流側に作用する上記浄水供給路側からの内圧を相殺する圧力キャンセル弁と、上記主開閉切換弁の下流側位置に介装されて注水又は遮断の開閉切換えを行う副開閉切換弁と、この副開閉切換弁と上記主開閉切換弁との間の位置に連通した状態で配設されて大気側との連通又は遮断の開閉切換えを行う負圧破壊弁と、上記主開閉切換弁及び圧力キャンセル弁がそれぞれ結合され進退方向への駆動力を受けて上記主開閉切換弁の開閉切換えを行う第１の弁軸と、上記副開閉切換弁及び負圧破壊弁がそれぞれ結合され進退方向への駆動力を受けて上記副開閉切換弁及び負圧破壊弁の双方の開閉切換えを行う第２の弁軸とを備えるものとする。そして、上記第２の弁軸として、駆動手段からの進退駆動力を受けて進退方向一側へ作動することにより、上記副開閉切換弁を閉弁状態から開弁切換えさせると共に上記負圧破壊弁を開弁状態から閉弁切換えさせて上記副開閉切換弁及び負圧破壊弁を定常状態から注水状態へ切換えさせる一方、進退方向他側へ作動することにより、上記注水状態から定常状態に切換えさせて復帰する構成とする。
【００２９】
この請求項３によれば、主開閉切換弁に圧力キャンセル弁を付設しているため、請求項１による作用の全てを得られる他に、第２の弁軸を進退作動させることにより副開閉切換弁及び負圧破壊弁の双方の開閉切換えを行うことが可能になる。そして、第１及び第２の２つの弁軸に対する進退駆動を制御することにより、全ての弁の開閉切換制御を行うことが可能となる。なお、第１及び第２の各弁軸に対する進退駆動力の付与は、駆動手段を個別に設けて各弁軸に個別に駆動力を付与するようにしても、共通の駆動手段により双方の弁軸に駆動力を付与するようにしてもいずれの方式をも採用することができる。
【００３０】
特に第２の弁軸に対する進退駆動力の付与については、次のようにすることもできる。すなわち、上記第２の弁軸に対し進退方向一側への駆動力を付与する駆動手段と、上記第２の弁軸に対し進退方向他側への戻し力を付与する戻しバネとを備え、上記駆動手段からの駆動力を受けて上記第２の弁軸が進退方向一側へ駆動されることにより副開閉切換弁及び負圧破壊弁が定常状態から注水状態に切換えられる一方、上記駆動手段による上記注水状態の維持力が解消されると上記戻しバネからの戻し力を受けて上記副開閉切換弁及び負圧破壊弁が上記注水状態から定常状態に切換えられて復帰するように構成する（請求項４）。つまり副開閉切換弁の開弁切換え及び負圧破壊弁の閉弁切換えは駆動手段からの駆動力により行わせ、逆の副開閉切換弁の閉弁切換及び負圧破壊弁の開弁切換えは戻しバネにより行わせるというものである。この場合、駆動手段を通電により駆動力を発揮する電磁式にしたり、あるいは、通電により回転して駆動力を発揮するものの非通電になれば脱調可能な回転駆動式のもの（例えばステッピングモータ）にすれば、停電発生時において負圧破壊弁を予備電源等の電源供給を必要とすることなく戻しバネにより自動的に開弁切換えさせて、逆流発生を阻止し得る状態に変換させることが可能になる。なお、戻しバネによる戻し力は上記第２の弁軸に対し直接に作用させても、副開閉切換弁もしくは負圧破壊弁を介して間接に作用させてもいずれでもよい。
【００３１】
また、上記の請求項３又は請求項４における第２弁軸の進退作動においては、さらに次の構成を追加することが好ましい。すなわち、上記第２の弁軸の進退方向一側への駆動による定常状態から注水状態への切換えの際に、上記第２の弁軸が負圧破壊弁を開弁状態から閉弁状態に切換えるだけストロークした後に、副開閉切換弁が上記第２の弁軸から作動力を受けて閉弁状態から開弁作動を開始するように上記副開閉切換弁と上記第２の弁軸とを関係付けるようにする（請求項５）。つまり、第２の弁軸を進退方向一側に駆動した場合の負圧破壊弁及び副開閉切換弁の作動タイミングとして、負圧破壊弁が閉弁した後に副開閉切換弁が開弁するように設定するものである。すなわち、上記第２の弁軸の進退方向一側への駆動により定常状態から注水状態への切換えを開始させると、上記第２の弁軸の駆動開始から前段のストロークにより負圧破壊弁が第２の弁軸から作動力を受けて閉弁状態に切換えられ、引き続いて後段のストロークにより副開閉切換弁が上記第２の弁軸から作動力を受けて開弁作動を開始して開弁状態に切換えられることになる。逆に、上記第２の弁軸が進退方向他側へ戻されると、先に副開閉切換弁が開弁状態から閉弁状態に復帰し、この閉弁状態への復帰の後に負圧破壊弁が閉弁状態から開弁作動を開始して開弁状態に切換えられることになる。
【００３２】
さらに、上記の請求項３〜請求項５のいずれかにおける第１及び第２の２つの弁軸の進退作動においては、次の構成を追加することが好ましい。すなわち、上記第１の弁軸及び第２の弁軸に対する進退方向一側への駆動力の付与タイミングとして、先に上記第２の弁軸に駆動力を付与して負圧破壊弁及び副開閉切換弁を定常状態から注水状態への切換えを完了させ、この完了後に上記第１の弁軸に駆動力を付与して主開閉切換弁を閉弁状態の定常状態から開弁状態の注水状態への切換えを行うように設定する（請求項６）。つまり、非注水状態である定常状態から注水状態へ切換える際の作動タイミングを明確化したものである。この場合には、負圧破壊弁を閉弁させ副開閉切換弁を開弁させた後に主開閉切換弁が開弁されて注水が実行されることになる。逆に注水状態から定常状態への切換えの際には、上記とは逆に第１の弁軸を駆動させて主開閉切換弁を閉弁させて遮断した後に、第２の弁軸を駆動させて副開閉切換弁を閉弁させ負圧破壊弁を開弁させるようにすればよい。
【００３３】
上記の請求項６による作動タイミングを実現するには第１及び第２の各弁軸を個別の駆動手段により駆動させるようにして、その各駆動手段の作動タイミングを制御するようにしてもよいが、上記第１及び第２の両弁軸を共通の駆動手段により駆動する場合においても次の構成を採用することにより可能となる。すなわち、上記第１の弁軸及び第２の弁軸のそれぞれに駆動力を付与する共通の駆動手段を備え、上記駆動手段として、上記第１及び第２の各弁軸に対し互いに直交するように配設されて上記駆動手段から回転駆動力を受ける回転作動軸と、この回転作動軸の回転駆動により揺動回転されて上記第１及び第２の各弁軸に対し進退方向の作動力を伝達する第１及び第２の一対のカム部材とを備えたものとする（請求項７）。これにより、請求項６による作動タイミングを一つの駆動手段により容易に実現させ得る。すなわち、一対のカム部材による第１及び第２の各弁軸に対する作動タイミングが請求項６の駆動力付与タイミングとなるように、上記一対のカム部材を互いに形状を変える、又は、同一形状であっても位相差を付けて回転作動軸に結合させるようにすれば、共通の駆動手段から駆動力の伝達を受けるようにしても請求項６を容易に実現し得ることになる。
【００３４】
また、この請求項７の如く第１及び第２の両弁軸をカム駆動により進退作動させるようにすることにより、主開閉切換弁のみならず負圧破壊弁及び副開閉切換弁の開閉切換えに要する駆動手段の必要回転量を極めて小さくして停電発生時の対策を容易にかつ大幅なコスト増を招くことなく実現し得る。すなわち、停電発生時には予備電源からの電源供給により上記駆動手段を回転駆動させて上記副開閉切換弁を閉弁させ負圧破壊弁を開弁させるようにした場合、その予備電源（例えば電解コンデンサ等）に要求される必要静電容量を極めて小さいものにすることが可能になり、予備電源に要するコストを低く抑えることが可能になる。
【００３５】
以上の請求項１〜請求項７のいずれかにおける副開閉切換弁に対し、その弁体を閉弁側に付勢するバネを備え、このバネとして副開閉切換弁の弁体を開弁側に吸引する下流側からの負の水頭圧に打ち勝って閉弁状態に維持し得るバネ荷重を有するように設定するようにしてもよい（請求項８）。このようにすることにより、貯槽が浄水供給路側よりも低位（例えば階下位置）に設置され、貯槽までの配管内の水柱により負の水頭圧が副開閉切換弁に作用することになるような場合であっても、その負の水頭圧に打ち勝って副開閉切換弁を確実に閉弁状態に維持させ得る。なお、上記の「バネ」は請求項４〜請求項７における戻しバネにより兼用させるようにしてもよい。
【００３６】
さらに、以上の請求項１〜請求項８のいずれかの負圧破壊装置を適用する具体的な対象としては、次のようなものとすることができる。すなわち、上記浄水供給路として、浄水の給水を受け加熱源により加熱して給湯栓側に給湯する給湯回路又は浄水の給水を受けて給水栓側に給水する給水回路とし、この給湯回路又は給水回路に対し大気開放の貯槽が分岐路を通して注湯又は注水可能に接続されたものである（請求項９）。なお、この場合、給湯回路から貯槽へは、給湯回路の加熱源を加熱作動させた場合に注ぎ込まれる注湯に加え、上記加熱源を非加熱作動のまま給水を注ぎ込む場合の注水がある。
【００３７】
【発明の効果】
以上、説明したように、請求項１〜請求項９のいずれかの負圧破壊装置によれば、主開閉切換弁に対し圧力キャンセル弁を付設しているため、主開閉切換弁の開閉切換えの際に抵抗として作用する浄水供給路側からの給水圧を相殺させてキャンセルすることができる。このため、主開閉切換弁の開閉切換えを極めて軽い駆動力により実現させることができ、主開閉切換弁として、従来のダイヤフラム弁に代えて、弁体により通路を直接に開閉させる単純なタイプのものを採用することができる。これにより、上記のダイヤフラム弁タイプのものを使用する場合の不利益、すなわち、装置全体を大型化させたり、分岐路の通路径を狭めて流通抵抗の増大を招いたり、ダイヤフラム弁のバウンド発生に伴う不都合を発生させたりという不利益を全て解消させることができ、装置全体のコンパクト化を図ることができる上に浄水供給路側から貯槽側への効率のよい注水を実現させることができる。
【００３８】
また、停電発生時対策として上記主開閉切換弁を閉弁作動させるための予備電源を備える場合であっても、上記主開閉切換弁に作動抵抗として作用する内圧を圧力キャンセル弁により相殺させているため、弁軸の駆動のための必要作動トルクを大幅に軽減することができ、その結果、上記予備電源に要求される駆動用電力エネルギーを大幅に小さいものにすることができる。このため、予備電源を搭載するにしてもその必要静電容量の大幅な小容量化を図ることができ、コストの大幅増大を招くことなく主開閉切換弁の自動閉弁により停電発生に起因する逆流入発生を阻止することができる
加えて、進退駆動力を受けた弁軸の作動により強制的に開弁させ得る負圧破壊弁を配設しているため、注水完了後の定常時には上記負圧破壊弁を強制的に開弁させておくことにより、たとえ主開閉切換弁や副開閉切換弁の全てに閉作動異常が生じていたとしても、浄水供給路側が負圧状態に陥れば上記開弁状態の負圧破壊弁からエアが即座に吸い込まれて負圧を解消することができ、貯槽側からの逆流入発生を確実に阻止することができる。
【００３９】
特に、請求項２によれば、作動トルクの軽減化に加え、弁軸の進退作動をカム駆動としているため、停電発生時において主開閉切換弁を自動閉弁させるための正逆他側回転の必要回転量を、弁軸自体の回転により進退方向他側へ作動させる場合と比べ大幅に減少させることができる。これにより、上記の自動閉弁のための駆動用電力エネルギーの大幅低減化を図ることができ、停電時対策として予備電源を搭載する場合であっても、その予備電源の必要静電容量のより一層の大幅な小容量化を実現してコスト増をより一層抑制しつつ停電発生時の逆流発生を回避することができる。
【００４０】
また、請求項３によれば、第１及び第２の２つの弁軸に対する進退駆動を制御することにより、全ての弁の開閉切換制御を行うことができるようになる。
【００４１】
請求項４によれば、請求項３における第２の弁軸を進退駆動させる駆動手段として、通電により駆動力を発揮する電磁式にしたり、あるいは、通電により回転して駆動力を発揮するものの非通電になれば脱調可能な回転駆動式のものを採用することができる一方、これらを採用したとしても停電発生時において負圧破壊弁を予備電源等の電源供給を必要とすることなく戻しバネにより自動的に開弁切換えさせて、逆流発生を阻止し得る状態に変換させることができる。
【００４２】
請求項５によれば、請求項３又は請求項４における第２弁軸を進退方向一側に駆動させた場合に、負圧破壊弁を確実に閉弁させた後に副開閉切換弁を開弁させるというように、負圧破壊弁及び副開閉切換弁の作動タイミングを設定することができる。
【００４３】
請求項６によれば、請求項３〜請求項５のいずれかにおける第１及び第２の２つの弁軸の進退作動による定常状態から注水状態への切換えとして、先に負圧破壊弁及び副開閉切換弁を定常状態から注水状態に切換えた上で、主開閉切換弁を閉弁状態の定常状態から開弁状態の注水状態へ切換えることができる。
【００４４】
請求項７によれば、請求項６による特定順序の作動タイミングを、共通の駆動手段により第１及び第２の両弁軸に進退駆動力を付与する場合においても容易に実現させることができる。しかも、進退駆動力の付与をカム駆動により行うようにしているため、主開閉切換弁のみならず負圧破壊弁及び副開閉切換弁の開閉切換えに要する駆動手段の必要回転量を極めて小さくすることができることになる。このため、停電発生時の対策として予備電源からの電源供給により上記駆動手段を回転駆動させて上記副開閉切換弁を閉弁させ負圧破壊弁を開弁させるようにする場合であっても、その予備電源に要求される必要静電容量を極めて小さいものにすることができ、予備電源に要するコストを低く抑えて大幅なコスト増を回避した状態で停電発生時の負圧発生に起因する逆流発生を回避することができるようになる。
【００４５】
請求項８によれば、貯槽が浄水供給路側よりも低位に設置されて貯槽までの配管内の水柱により負の水頭圧が副開閉切換弁に作用することになるような場合であっても、その負の水頭圧に打ち勝って副開閉切換弁を確実に閉弁状態に維持させることができる。
【００４６】
請求項９によれば、以上の請求項１〜請求項８のいずれかの負圧破壊装置を適用する具体的な対象として好適な構成を特定することができる。
【００４７】
【発明の実施の形態】
以下、本発明の実施形態を図面に基づいて説明する。
【００４８】
＜第１実施形態＞
図１は、本発明の第１実施形態に係る負圧破壊装置６を適用した給湯装置１を示している。つまり、本実施形態は浄水供給路としての給湯回路２から分岐する注湯路（分岐路）５０を通して貯槽としての浴槽３に注湯・注水可能とした場合に本発明を適用したものである。
【００４９】
上記給湯装置１は、給湯機能を実現する給湯回路２と、浴槽３内の湯水の追い焚き機能を実現する強制循環式の追い焚き循環回路４と、上記給湯回路２と追い焚き循環回路４とを接続して上記浴槽３に対する注湯又は注水（以下、両者を含めて単に「注湯」という）を行う注湯路５０とを備えたものである。
【００５０】
上記給湯回路２は、水道管に接続された給水路２１から導入される水（浄水）を給湯側熱交換器２２において燃焼バーナ２３の燃焼熱との熱交換加熱により加熱し、加熱後の湯を出湯路２４及び給湯路２５を通して下流端の給湯栓２６ａ，２６ｂまで給湯させるようになっている。ここで、燃焼缶体内に配設された上記熱交換器２２及び燃焼バーナ２３が加熱源を構成している。上記給水路２１と出湯路２４との間にはバイパス路２７が設けられて、調整弁２７ａによる水の混合調節制御により設定温度への温度調整が行われるようになっている。上記給湯栓２６ａは台所等に配設されたカランであり、給湯栓２６ｂは浴室や洗面台等に設置されたシャワーカランである。
【００５１】
上記給水路２１には入水流量センサ２８と、入水温度センサ２９とが配設されている。また、上記出湯路２４には上記給湯栓２６もしくは注湯路５０に供給される湯水の温度を検出する給湯温度センサ３１と、流量調整弁３０とが上流側から順に配設されている。給湯温度や注湯温度を所定の設定温度になるように燃焼バーナ２３の燃焼を制御する給湯制御がコントローラ１１により行われ、このコントローラ１１では主として上記入水流量センサ２８、入水温度センサ２９及び給湯温度センサ３１からの各検出値に基づいて上記給湯制御を行うようになっている。
【００５２】
上記追い焚き循環回路４は、それぞれ浴槽３に連通接続された戻り路４１及び往き路４２からなる循環路４３を備え、上記戻り路４１から循環ポンプ４４の作動により風呂側熱交換器４５に戻される浴槽３内の湯水を燃焼バーナ４６の燃焼熱により熱交換加熱し、加熱後の湯水を往き路４２を通して再び上記浴槽３内に供給して追い焚きさせるようになっている。
【００５３】
上記戻り路４１には、循環湯水の循環方向上流側から順に循環ポンプ４４と、循環流の通過によりフラップが開いて循環判定のＯＮ指令が出力される水流スイッチ４８と、浴槽３内から風呂側熱交換器４５に戻される循環湯水の温度を検出する戻り温度センサ４９とが配設されている。また、水圧検出により浴槽３の水位を検出する水位センサ４７が後述の注湯路５０の下流端側位置に配設されている。そして、この水位センサ４７からの検出値に基づいて所定水位までの注湯制御が上記コントローラ１１により行われ、上記戻り温度センサ４９からの検出値に基づいて追い焚き時における浴槽３内の湯水温度が把握されて所定温度までの追い焚き制御が上記コントローラ１１により行われ、上記水流スイッチ４８からの出力信号により追い焚き制御において循環作動が正常か否かの判定が上記コントローラ１１により行われることになる。
【００５４】
上記注湯路５０は上流端が上記流量調整弁３０の下流側位置から分岐し、下流端が上記循環路４３のいずれかの位置（図１では戻り路４１の循環ポンプ４４よりも下流側位置を例示）に連通され、この注湯路５０を通して上記給湯回路２からの湯水を追い焚き循環回路４に流入させて浴槽３に注湯し得るようになっている。そして、上記注湯路５０には、図２又は図３にも詳細を示すように、負圧破壊装置６が介装されている。なお、図２においては注湯完了後に注湯路５０を遮断して次回の注湯まで待機する定常状態（以下「定常時」ともいう）を図示し、図３においては注湯時の注湯状態を図示している。
【００５５】
すなわち、上記負圧破壊装置６は、流量調整弁３０の下流側位置から分岐した後の注湯路５０に対し上流側から順に介装された逆止弁６１と、主開閉切換弁６２と、副開閉切換弁６３とを備えている。加えて、上記負圧破壊装置６は、上記主開閉切換弁６２及び副開閉切換弁６３の両者間の中間位置の注湯路５０に連通した状態で配設された負圧破壊弁６４と、上記主開閉切換弁６２の上流側に作用する上記注湯回路２側からの内圧を相殺する圧力キャンセル弁６５とを備えたものである。この圧力キャンセル弁６５と主開閉切換弁６２とは共通の第１の弁軸６６にそれぞれ結合される一方、上記負圧破壊弁６４と副開閉切換弁６３とは共通の第２の弁軸６７にそれぞれ結合されている。そして、上記第１の弁軸６６及び第２の弁軸６７が共通の駆動手段としての電動モータ（例えばサーボモータ）６８からそれぞれ舌片状の第１及び第２のカム部材７１，７２を介して進退作動力を受けることにより、上記主開閉切換弁６２、副開閉切換弁６３及び負圧破壊弁６４が所定の状態に開閉切換えされるようになっている。
【００５６】
以下、負圧破壊装置６の各構成要素について詳細に説明する。なお、図中５１は例えば回転可能な羽根車を備え注湯流量を検出する注湯流量センサであり、この注湯流量センサ５１は負圧破壊装置として必須の要素ではない。
【００５７】
上記逆止弁６１は、注湯時の給水圧を受けて開弁して浴槽３側への流通をのみ許容する一方、給水圧が解消するとバネ６１１により閉弁状態に復帰されて閉弁状態に維持される構造を有している。なお、逆止弁６１は、主開閉切換弁６２が閉弁状態であれば両者６１と６２との間に封入された状態の水等の流体により上流側から給水圧を受けても閉弁状態に維持され、上記主開閉切換弁６２が開弁されて下流側が開放されと上記給水圧により開弁されることになる。
【００５８】
上記第１の弁軸６６及び第２の弁軸６７は上記電動モータ６８の回転作動軸６８１と互いに直交するように互いに平行に配設され、その進退方向（図２及び図３の上下方向）に移動可能にハウジングにより支持されている。そして、各弁軸６６，６７は、上記各カム部材７１，７２から進退方向への押圧力又はこの押圧力の解除を受けるピン６６ａ，６７ａと、この各ピン６６ａ，６７ａに固定されて上記進退方向に延びる軸体６６ｂ，６７ｂとから構成されている。そして、上記第１カム部材７１（図４も併せて参照）が図２の定常状態から反時計方向に所定量回転駆動（正逆一側回転駆動）されることにより上記第１の弁軸６６を下方に前進作動（進退方向一側へ作動）させて上記主開閉切換弁６２が開弁した図３の注湯状態に切換える一方、上記第１カム部材７１が上記注湯状態から時計方向に上記の所定量だけ逆回転駆動（正逆他側回転駆動）されることにより上記第１の弁軸６６に対する押圧力を解除させつつ第１の弁軸６６を後述の戻しバネ７３の圧縮復元力により上方に後退作動（進退方向他側へ作動）させて上記主開閉切換弁６２が閉弁した図２の定常状態に復帰切換えさせるようになっている。
【００５９】
一方、上記第２カム部材７２が図２の定常状態から反時計方向に所定量回転駆動（正逆一側回転駆動）されることにより上記第２の弁軸６７を下方に前進作動（進退方向一側へ作動）させて上記副開閉切換弁６３が開弁し負圧破壊弁６４が閉弁した図３の注湯状態に切換える一方、上記第２カム部材７２が上記注湯状態から時計方向に上記の所定量だけ逆回転駆動（正逆他側回転駆動）されることにより上記第２の弁軸６７に対する押圧力を解除させつつ第２の弁軸６７を後述の戻しバネ７４の圧縮復元力により上方に後退作動（進退方向他側へ作動）させて上記副開閉切換弁６３が閉弁し負圧破壊弁６４が開弁した図２の定常状態に復帰切換えさせるようになっている。
【００６０】
上記の第１カム部材７１と第２カム部材７２とは、図４に示すように電動モータ６８の回転作動軸６８１を正逆一側回転（反時計方向回転）させた際に、第２カム部材７２が先に第２の弁軸６７を押圧して前進作動させ、次に第１カム部材７１が第１の弁軸６６を押圧して前進作動させるように設定されている。
【００６１】
上記第１の弁軸６６にはその先端位置に主開閉切換弁６２が固定され、この主開閉切換弁６２の上流側受圧面６２１に相対向して圧力キャンセル弁６５が固定されている。この圧力キャンセル弁６５は、上記主開閉切換弁６２に対し近付く側への移動がストッパ６５１により阻止される一方、離れる側への移動が軸体６６ｂ基端側の小径雄ネジ部をピン６６ａの雌ネジ部にねじ込んで圧力キャンセル弁６５を挟み付けて阻止され、これにより第１の弁軸６６に対する固定が行われている。そして、この圧力キャンセル弁６５と主開閉切換弁６２との間に注湯路５０が区画形成されており、図３に示すように主開閉切換弁６２の弁座６２２により囲まれる上記上流側受圧面６２１と、圧力キャンセル弁６５の相対向面６５２とが互いに略同等の受圧面積になるように設定されいてる。これにより、上記注湯路５０内の内圧を主開閉切換弁６２と圧力キャンセル弁６５との双方に互いに逆向きに作用させて、主開閉切換弁６２の進退作動（開閉切換作動）の際に上記内圧に基づき作用する作動抵抗圧力をキャンセルするようにしている。
【００６２】
また、上記主開閉切換弁６２にはハウジングとの間に戻しバネ７３が掛け渡されており、この戻しバネ７３により第１の弁軸６６を後退側（進退方向他側）に付勢して注湯状態から定常状態へ復帰切換えさせると共に、上記主開閉切換弁６２を閉弁状態に維持させるようになっている。
【００６３】
なお、上記圧力キャンセル弁６５の背面側は貫通孔６５３を通して大気と連通され、また、ハウジングにより形成された収容筒部との間に介装されたシール部材６５４としては摺動抵抗軽減化の観点よりＯ形リングではなくてＵ形リング又はＸ形リングを採用している（図例ではＵ形リングを図示）。
【００６４】
一方、上記第２の弁軸６７の中間位置には負圧破壊弁６４の弁体６４１が相対移動可能に支持され、先端位置には副開閉切換弁６３の弁体６３１が相対移動可能に支持されている。上記負圧破壊弁６４の弁体６４１は上記副開閉切換弁６３に対し近付く側（進退方向一側）への移動がストッパ６４２により阻止される一方、バネ６４３により上記ストッパ６４２に向けて付勢されている。また、上記副開閉切換弁６３の弁体６３１は上記負圧破壊弁６４に対し近付く側（進退方向他側）への移動が第２の弁軸６７の先端６７１により阻止される一方、戻しバネ７４により上記先端６７１に向けて付勢されている。なお、上記先端６７１がストッパを構成することになるが、先端６７１の代わりにストッパを別に設けるようにしてもよい。また、上記バネ６４３は後述の注湯状態においては弁体６４１を閉弁状態に維持させる維持力を発揮するものであり、上記戻しバネ７４は第２の弁軸６７を後退側（進退方向他側）に付勢して注湯状態から定常状態へ復帰切換えさせると共に、上記副開閉切換弁６３の弁体６３１を閉弁状態に維持させるようになっている。
【００６５】
加えて、第２の弁軸６７の先端６７１と、副開閉切換弁６３の弁体６３１とは定常状態、すなわち、閉弁状態において進退方向に所定の隙間Ｓ_１（図２参照）が設定され、この隙間Ｓ_１は負圧破壊弁６４の弁体６４１と弁座６４４との間の進退方向間隔Ｓ_２と等しく（あるいは少なくとも大きく）なるように設定されている（Ｓ_１＝Ｓ_２）。そして、第２の弁軸６７が定常状態から間隔Ｓ_１に相当するストロークだけ前進作動すると負圧破壊弁６４が閉弁し、さらに前進作動すると副開閉切換弁６３が上記先端６７１に押されて開弁作動を開始し、負圧破壊弁６４の閉弁時点からさらにＳ_３（図３参照）のオーバーストロークだけ前進作動すれば副開閉切換弁６３が間隔Ｓ_４だけ開弁することになる。ここで、Ｓ_１＝Ｓ_２であれば、Ｓ_４＝Ｓ_３となり、副開閉切換弁６３が開弁した注湯状態までの第２の弁軸６７の総ストロークはＳ_５（Ｓ_５＝Ｓ_１＋Ｓ_４）となる。
【００６６】
つまり、第２の弁軸６７の前進作動に伴なう負圧破壊弁６４及び副開閉切換弁６３の切換順（切換タイミング）が、まず先に負圧破壊弁６４が閉弁し、次に副開閉切換弁６３が開弁するように設定されている。そして、上記のオーバーストローク分の前進作動によりバネ６４３が縮められて負圧破壊弁６４の弁体６４１を強固に閉弁状態に維持するすることになる（図３参照）。一方、このように設定することにより、上記第２の弁軸６７を逆に後退作動させて注湯状態から定常状態に復帰させる場合には、まず先に副開閉切換弁６３が閉弁し、次に負圧破壊弁６４が開弁することになる。
【００６７】
次に、切換制御について説明する。定常状態から注湯状態に切換えるには、まず電動モータ６８に通電して回転作動軸６８１を反時計方向に所定量だけ回転駆動させる。これにより、まず第２の弁軸６７が第２カム部材７２により押されて前進作動し、まず負圧破壊弁６４が閉弁した状態に切換えられた上で、副開閉切換弁６３が開弁した状態に切換えられる。次に、第１の弁軸６６が第１カム部材７１により押されて前進作動し、主開閉切換弁６２が開弁した状態に切換えられる。これにより、逆止弁６１が給湯回路２側からの給水圧を受けて開弁されて給湯回路２から浴槽３側への注湯が可能になる（図３参照）。
【００６８】
一方、この注湯状態から逆に定常状態への切換えは、まず上記の電動モータ６８を逆回転駆動させて回転作動軸６８１を時計方向に上記と同量だけ回転駆動させる。これにより、上記とは逆に第１カム部材７１の逆回転に伴い戻しバネ７３からの圧縮復元力を受けて先に第１の弁軸６６が後退作動を開始し、主開閉切換弁６２が閉弁状態に切換えられる。これにより、注湯が遮断されるため、上記逆止弁６１が閉弁する。次いで第２カム部材７２の逆回転に伴い戻しバネ７４からの圧縮復元力を受けて第２の弁軸６７が後退作動を開始する。この後退作動により、まず先に副開閉切換弁６３が閉弁状態に切換えられ、次いで負圧破壊弁６４が開弁状態に切換えられる。
【００６９】
上記の主開閉切換弁６２の閉弁作動の際、逆止弁６１との間の注湯路５０内に封入された残圧が作動抵抗として上記主開閉切換弁６２に作用することになるものの、同圧の残圧が圧力キャンセル弁６５に対し逆向きに作用するため、上記の作動抵抗が相殺されてキャンセルされる結果、第１の弁軸６６を極めて軽い力で後退作動させ得ることになる。つまり、第１カム部材７１の逆回転により第１の弁軸６６に対する押圧力を解除するだけで、第１の弁軸６６は戻しバネ７３により上記主開閉切換弁６２を閉弁作動させることができ、上記戻しバネ７３のバネ荷重も比較的小さいものに設定することができる。一方、主開閉切換弁６２が閉弁した後に副開閉切換弁６３の閉弁により両者間６２，６３の注湯路５０に残る残圧が、続いて開弁される負圧破壊弁６４を通して大気開放口６４５から開放される。以上で定常状態への切換えが完了する。
【００７０】
なお、以上の電動モータ６８の駆動制御による注湯状態と定常状態との切換制御は、コントローラ１１による注湯制御によって行われるようになっている。すなわち、この注湯制御は例えばリモコンの湯張りスイッチがＯＮ操作されると上記の注湯状態への切換制御が開始され、注湯流量センサ５１からの検出値に基づく浴槽３への湯張り量が所定の設定湯張り量に到達するか、あるいは、水位センサ４７からの水位検出値が所定の設定水位に到達すれば、注湯を完了させて注湯状態から定常状態への切換制御が行われる。
【００７１】
以上の負圧破壊装置６によれば、上記の注湯後の定常状態において、給湯回路２側が負圧状態に陥っても、その負圧が逆止弁６１に対し閉弁側に作用する上に、主開閉切換弁６２や副開閉切換弁６３が閉弁状態に維持されているため、給湯回路２側と浴槽３側とは遮断状態に維持されることになる。この際に、上記逆止弁６１、主開閉切換弁６２や、副開閉切換弁６３の全てに異物噛み込み等により閉作動異常が生じていたとしても、負圧破壊弁６４が強制的に開弁されているため、この負圧破壊弁６４及び大気開放口６４５から即座にエアが吸い込まれて負圧が解消される。以上により、各弁の閉作動異常の発生の有無に拘わらず、給湯回路２に負圧が発生しても浴槽３側から給湯回路２側への逆流入の発生を阻止することができる。
【００７２】
また、上記の負圧状態の発生が停電に起因するものである場合もあることから、停電発生時においても上記の閉作動異常発生に起因する逆流入発生を確実に阻止するために、停電発生時に第２の弁軸６７を定常状態に復帰切換えさせる分の駆動用電源を電動モータ６８に供給するためのバックアップ電源（例えば電解コンデンサ）等の予備電源を搭載するようにしてもよい。この場合であっても、その予備電源の必要静電容量として極めて小さいものにして僅かなコスト増に抑制することができる。
【００７３】
すなわち、上述の如く圧力キャンセル弁６５により主開閉切換弁６２の閉弁切換時の抵抗圧力がキャンセルされ、第１カム部材７１を逆回転駆動させて第１の弁軸６６に対する押圧力を解除するだけで第１の弁軸６６を戻しバネ７３により復帰させ得るため、電動モータ６８の逆回転駆動は極めて低い作動トルクで済む上に、電動モータ６８の回転作動軸６８１の必要回転量も第１カム部材７１を所定量逆回転させるだけというように僅かで済む。その上に、上記の電動モータ６８の逆回転駆動により先に主開閉切換弁６２が閉弁され、その後に副開閉切換弁６３及び負圧破壊弁６６が定常状態に切換えられるため、第２の弁軸６７の後退作動も上記と同様に極めて低い作動トルク及び僅かな回転量で済む。このため、停電発生時に電動モータ６８に電源供給するための予備電源を極めて小さい静電容量のものにしても、負圧破壊部６４のみならず副開閉切換弁６３及び主開閉切換弁６２をも定常状態に確実に復帰切換えさせることができる。
【００７４】
なお、上記の如き予備電源を搭載するには次のようにすればよい。すなわち、例えば、コントローラ１１と、電動モータ６８とをそれぞれ制御信号ライン及び電源供給ラインにより互いに接続する一方、上記コントローラ１１に予備電源として比較的小静電容量のコンデンサ（電解コンデンサ）を備える。そして、通常時には上記電動モータ６８への駆動電流を主電源供給ラインから供給する一方、停電発生時にはその停電発生によるスイッチ切換により上記電動モータ６８に対する所定回転方向の回転駆動（上記の場合であると逆回転駆動、後述の「第１実施形態の他の態様；その１」の場合であると正回転駆動）のための駆動電流を上記コンデンサから供給するように構成すればよい。
【００７５】
さらに、注湯後の定常状態において、給湯装置１が階下に設置され浴槽３が階上位置に設置されて配管内の正の水頭圧が給湯回路２側に作用したとしても、上記正の水頭圧が副開閉切換弁６３を閉弁側に押し付ける側に作用するため、ここで遮断されて給湯回路２側に向かう逆流が生じることもない。この際、上記副開閉切換弁６３に上記の如き閉作動異常が生じていたとしても、開弁状態の負圧破壊弁６４から大気開放口６４５を通してオーバーフローされるだけで、給湯回路２側への逆流は確実に阻止される。
【００７６】
逆に、注湯後の定常状態において、給湯装置１が階上に設置され浴槽３が階下位置に設置されて配管内の負の水頭圧が上記副開閉切換弁６３に作用する場合であっても、戻しバネ７４のバネ荷重を予想される負の水頭圧に打ち勝ち得るように設定すれば副開閉切換弁６３を確実に閉弁状態に維持することができる。この場合、戻しバネ７４が比較的強くても副開閉切換弁６３の開弁切換えは電動モータ６８の駆動力により行われるため支障なく閉弁切換えを実行させることができる。
【００７７】
しかも、例えば給湯回路２側の給湯栓２６ａ，２６ｂ等の急開閉操作に起因する脈動が給湯回路２から注湯路５０に伝搬したとしても、従来の負圧破壊装置５の如きダイヤフラム弁が存在せず、ダイヤフラム弁のバウンドに起因する漏水が発生することもない。
【００７８】
（第１実施形態の他の態様；その１）
停電発生時対策として予備電源を搭載する場合に、注湯状態における第１及び第２の弁軸６６，６７に対する押圧力を解除して両弁軸６６，６７を定常状態まで復帰切換えさせる方策として、上述の如く第１及び第２の両カム部材７１，７２を逆回転駆動（時計方向回転駆動）させることにより行うのではなくて、両カム部材７１，７２をさらに僅かに正回転駆動させることにより行うようにしてもよい。
【００７９】
すなわち、注湯状態で停電が発生した場合、予備電源からの電源供給を受けた電動モータ６８により注湯状態の両カム部材７１，７２（図４に一点鎖線及び二点鎖線で示すカム部材）をあと僅かだけさらに正回転駆動（反時計方向回転駆動）させると、カム部材７１，７２と弁軸６６，６７との係合が外れ、このため、弁軸６６，６７に対する押圧力が解除されることになる。これにより、第１の弁軸６６は戻しバネ７３により、第２の弁軸６７は戻しバネ７４によりそれぞれ後退作動されて各弁６２，６３，６４を定常状態に復帰切換えさせることができるようになる。
【００８０】
この場合には、電動モータ６８の必要回転量が逆回転駆動させる場合よりも小さい角度の正回転駆動で済むため、コンデンサ等の予備電源に要求される必要静電容量をより小容量化することができ、予備電源の搭載に伴うコスト増をより一層抑制することができる。なお、この場合には停電が解消すれば、コントローラ１１によりカム部材７１，７２の位置を初期位置にリセットさせるように制御すればよい。
【００８１】
以上の技術思想を特許請求の範囲の請求項２又は請求項８に記載の負圧破壊装置に従属させるものとして表現すると、次のようになる。すなわち、停電時用予備電源手段を備え、この予備電源手段は停電時に上記駆動手段に対し定常状態におけるカム部材と弁軸との係合を解除させて上記弁軸をバネ復帰させるよう上記カム部材をさらに正逆一側回転させる駆動電源を供給するように上記駆動手段と接続されている、負圧破壊装置。
【００８２】
（第１実施形態の他の態様；その２）
駆動手段としての電動モータ６８として非通電時には脱調可能なもの（例えばステッピングモータ）を採用し、戻しバネ７３，７４のバネ荷重設定を上述のものとは異なり所定量増大することにより、停電時対策としての予備電源の搭載そのものを省略しても、停電発生時には各弁６２，６３，６４を自動的に定常状態に復帰切換えさせることができる。
【００８３】
すなわち、上記戻しバネ７３のバネ荷重を、主として圧力キャンセル弁６５の摺動抵抗に起因する第１の弁軸６６の作動抵抗に加え、上記ステッピングモータ６８の非通電時における回転作動軸６８１の回転抵抗をも考慮した復帰切換えに対する抵抗力よりも大きくなるように設定する。これにより、上記ステッピングモータ６８に対する通電が停電発生により停止されても、上記のバネ荷重設定の戻しバネ７３の圧縮復元力のみによって第１の弁軸６６を後退作動させて定常状態に自動復帰させることができるようになる。
【００８４】
これにより、停電発生時に給湯回路２側が負圧状態に陥り、しかも、主開閉切換弁６２及び副開閉切換弁６３が共に閉作動異常に陥っていたとしても、開弁状態に自動復帰された負圧破壊弁６４からのエア吸い込みにより上記負圧が解消されて浴槽３側からの逆流発生を確実に阻止することができる。そして、このような効果を予備電源の搭載によるコスト増を全て回避しつつ得ることができるようになる。
【００８５】
以上の技術思想を特許請求の範囲の請求項２又は請求項８に記載の負圧破壊装置に従属させるものとして表現すると、次のようになる。すなわち、駆動手段は非通電時には脱調可能に構成され、弁軸をバネ復帰させる戻しバネは上記非通電時における駆動手段の位置保持力よりも大きいバネ荷重を有するように設定されている、負圧破壊装置。
【００８６】
＜第２実施形態＞
図５及び図６は第２実施形態の負圧破壊装置８を示すものであり、図５は定常状態、図６は注湯状態をそれぞれ示している。この第２実施形態の負圧破壊装置８は、第１実施形態の負圧破壊装置６に対しパイロット式ダイヤフラム弁を備えた注湯電磁弁６９を念のためさらに追加したものである。従って、この注湯電磁弁６９の追加を第１実施形態の他の態様：その１又はその２に適用してももちろんよい。追加した注湯電磁弁６９の他の構成要素は上記第１実施形態の負圧破壊装置６と同じである。以下、第１実施形態と同じ構成要素については第１実施形態と同じ符号を付してその詳細な説明を省略し、以下、異なる要素について主として説明する。
【００８７】
上記注湯電磁弁６９はノーマルクローズタイプの電磁制御弁により構成され、パイロット式ダイヤフラム弁６９１を備えたものである。すなわち、可撓性のダイヤフラム弁６９１の一側に対し先端周囲に弁座部を有する筒状弁座６９２が配設される一方、他方にダイヤフラム室６９３が区画形成されている。そして、上記筒状弁座６９２の内部が下流側（浴槽３側）に連通され外周側のドーナッツ環状空間６９４が上流側（給湯回路２側）に連通されており、この筒状弁座６９２の先端に対し上記ダイヤフラム弁６９１が弾性変形により接離可能に開閉して給湯回路２側と浴槽３側とを連通又は遮断の開閉切換えが行われるようになっている。上記ダイヤフラム室６９３にはブリード孔６９１ａを通して上流側の圧力（給湯回路２側の給水圧）がブリードインされ、この給水圧によりダイヤフラム弁６９１を閉弁状態に維持するようになっている。
【００８８】
一方、上記ダイヤフラム弁６９１には筒状弁座６９２の内部と連通するセンター孔６９５が貫通され、このセンター孔６９５が非通電時（定常時）はプランジャ６９６によって閉止される一方、通電時（注湯時）には電磁石６９７によりプランジャ６９６がバネ６９８に抗して後退されてダイヤフラム室６９３と連通させ、これにより、ダイヤフラム弁６９１を開弁状態に変換させるようになっている。つまり、非通電時には上記プランジャ６９６がバネ６９８により押されて上記センター孔６９５を閉止し、これにより、ダイヤフラム弁６９１を上記給水圧により閉弁状態に維持する一方、通電時には上記プランジャ６９６が電磁石６９７により後退駆動されてダイヤフラム弁６９１を開弁作動させるノーマルクローズタイプに構成されている。
【００８９】
この第２実施形態の場合の切換制御について説明すると、定常状態から注湯状態に切換えるには、第１実施形態の場合と同様に電動モータ６８を正回転駆動（反時計方向回転駆動）させ、まず第２の弁軸６７の前進作動により負圧破壊弁６４を閉弁させた上で副開閉切換弁６３を開弁させ、次に第１の弁軸６６の前進作動により主開閉切換弁６２を開弁させる。そして、最後に注湯電磁弁６９に通電してダイヤフラム弁６９１を開弁させる。これにより、逆止弁６１が給湯回路２側からの給水圧を受けて開弁されて給湯回路２から浴槽３側への注湯が可能になる（図６参照）。
【００９０】
一方、この注湯状態から逆に定常状態への切換えは、まず上記の注湯電磁弁６９に対する通電を停止することによりダイヤフラム弁６９１を閉弁状態にバネ復帰させる。これにより、注湯が遮断されるため、上記逆止弁６１が閉弁する。次いで上記電動モータ６８を逆回転駆動（時計方向回転駆動）させることにより、上記とは逆に主開閉切換弁６２を閉弁させ、副開閉切換弁６３を閉弁させ、負圧破壊弁６４を開弁させる。
【００９１】
なお、以上の電動モータ６８の駆動制御や、注湯電磁弁６９への通電制御による注湯状態と定常状態との切換制御は、第１実施形態において説明したと同様にコントローラ１１による注湯制御によって行われるようになっている。
【００９２】
以上の第２実施形態によれば、第２の弁軸６７に結合された副開閉切換弁６３及び負圧破壊弁６４や、第１の弁軸６６に結合された主開閉切換弁６２及び圧力キャンセル弁６５よりも上流側位置の注湯路５０に対し注湯電磁弁６９が追加介装されているため、注湯状態及び定常状態の相互切換えに対する確実性を第１実施形態よりもさらに増大させ得ることになる。また、定常状態から注湯状態への切換えに際しては下流側の主開閉切換弁６２、負圧破壊弁６４及び副開閉切換弁６３の開閉切換弁が完了するまでは注湯電磁弁６９が閉弁状態に維持されている一方、注湯状態から定常状態への切換えに際しては上記注湯電磁弁６９を最初に閉弁状態に切換えるため、第１の弁軸６６と第２の弁軸６７との作動タイミングの先後を第１実施形態の如く特定のものにする必要はなく、第１カム部材７１及び第２カム部材７２を同じ形状及び同じ配置にして簡略化することもできる。
【００９３】
以上の第２実施形態の技術思想を表現すると次のようになる。ここでは、上記の注湯電磁弁６９を主開閉切換弁として、主開閉切換弁６２を第１副開閉切換弁として、副開閉切換弁６３を第２副開閉切換弁としてそれぞれ把握する。
【００９４】
浄水が所定の給水圧を受けて供給される浄水供給路に対しこの浄水供給路から分岐する分岐路を通して大気開放の貯槽が注水可能に接続され、上記分岐路に介装されて上記浄水供給路と貯槽とを注水切換可能にしつつ負圧を破壊する負圧破壊装置において、
上記分岐路に対し上流側から順に、注水又は遮断の開閉切換えを行う駆動式主開閉切換弁と、第１及び第２の一対の駆動式副開閉切換弁とがそれぞれ介装され、上流側の第１副開閉切換弁にはこの第１副開閉切換弁の上流側に作用する上記浄水供給路側からの内圧を相殺する圧力キャンセル弁が付設され、上記第１副開閉切換弁と下流側の第２副開閉切換弁との間の位置に連通されて大気側との連通又は遮断の開閉切換えを行う駆動式の負圧破壊弁が配設されており、
上記第１副開閉切換弁及び圧力キャンセル弁は、進退方向への駆動力を受けて上記第１副開閉切換弁の開閉切換えを行う第１の弁軸にそれぞれ結合され、上記第２副開閉切換弁及び負圧破壊弁は、進退方向への駆動力を受けて上記第２副開閉切換弁及び負圧破壊弁の双方の開閉切換えを行う第２の弁軸にそれぞれ結合され、
上記第２の弁軸は、駆動手段からの進退駆動力を受けて進退方向一側へ作動することにより、上記第２副開閉切換弁を閉弁状態から開弁切換えさせると共に上記負圧破壊弁を開弁状態から閉弁切換えさせて上記第２副開閉切換弁及び負圧破壊弁を定常状態から注水状態へ切換えさせる一方、進退方向他側へ作動することにより、上記注水状態から定常状態に切換えさせて復帰するように構成されていることを特徴とする負圧破壊装置。
【００９５】
＜他の実施形態＞
なお、本発明は上記第１又は第２実施形態及びこれらの他の態様で記載した構成に限定されるものではなく、その他種々の実施形態を包含するものである。すなわち、上記第１又は第２実施形態では、第１の弁軸６６及び第２の弁軸６７を共通の駆動手段としての電動モータ６８により進退作動させる場合について説明したが、これに限らず、上記第１の弁軸６６及び第２の弁軸６７をそれぞれ個別の駆動手段により進退作動させるようにしてもよい。この場合には個別の駆動手段として、上記第１又は第２実施形態のように電動モータとカム部材との組み合わせにより各弁軸を個別にカム駆動させるようにしてもよいし、あるいは、各弁軸を進退方向に直動させるシリンダ等や電磁式駆動手段を採用するようにしてもよい。例えば図７には第２実施形態を例にして各弁軸６６，６７に対する個別の駆動手段として電磁式駆動手段９１，９２を採用した場合を図示している。
【００９６】
また、上記実施形態では、給湯回路２から浴槽３への注湯を、間に追い焚き循環回路４を介して行う給湯装置を例にして負圧破壊装置６，８，９を適用した場合を示したが、これに限らず、追い焚き循環回路４を省略して、つまり、風呂釜部分を省略して給湯回路２から浴槽３に対し直接に注湯する構成の給湯装置に本発明の負圧破壊装置を適用してもよい。この場合の「注湯」は所定温度の湯となる。
【００９７】
上記実施形態では、給湯回路２からの注湯先が浴槽３である場合の給湯装置を例にして負圧破壊装置６を適用した場合を説明したが、これに限らず、給湯回路２又は注水回路からの注湯・注水先を洗濯槽とする給湯装置に本発明の負圧破壊装置を適用してもよく、この場合にも同様の作用効果を得ることができる。この場合には、給湯回路２又は注水回路からの分岐路である注湯路５０又は注水路の下流端を洗濯槽の底部に連通接続し、洗濯槽に対し洗濯用の湯又は水を注湯・注水し得るようにすればよい。上記洗濯槽が大気開放の貯槽であり、ここで使用されている湯又は水は雑水となるため、浴槽の場合と同様に逆流発生等を防止する必要がある。
【００９８】
さらに、本発明の負圧破壊装置を上記実施形態で説明した給湯装置以外に適用することもできる。例えば、上水道管路から、あるいは、受水槽からポンプ圧送による給水圧により浄水が供給される管路（例えば浄水の供給を受けて給水栓に給水する給水回路等の浄水供給路）から分岐する分岐管を大気開放の貯槽（例えば上述の浴槽又は洗濯槽）の底部に連通接続し、注水用開閉弁の開閉切換により注水可能とした場合に、上記分岐管に上記実施形態の負圧破壊装置６，８，９を介装させるようにしてもよい。この場合にも、閉弁作動異常や停電発生に起因する上記貯槽から浄水供給路側への逆流発生を上記実施形態と同様に確実に防止し得ることになる。
【００９９】
なお、上記第１又は第２実施形態等においては、主として組み付け作業の便宜を考慮して弁軸６６，６７をピン６６ａ，６７ａと軸体６６ｂ，６７ｂとに分割しているが、もちろん当初から一体物により形成してもよい。
【図面の簡単な説明】
【図１】本発明の実施形態を適用した給湯装置を示す模式図である。
【図２】第１実施形態の負圧破壊装置の定常状態を示す断面説明図である。
【図３】第１実施形態の負圧破壊装置の注湯状態を示す図２対応図である。
【図４】第１実施形態のカム部材の部分の拡大説明図である。
【図５】第２実施形態の負圧破壊装置の定常状態を示す断面説明図である。
【図６】第２実施形態の負圧破壊装置の注湯状態を示す図５対応図である。
【図７】他の態様を示す図５対応図である。
【図８】従来の負圧破壊装置を適用した給湯装置を示す図１対応図である。
【符号の説明】
２給湯回路（浄水供給路）
３浴槽（貯槽）
６，８，９負圧破壊装置
２６ａ，２６ｂ給湯栓（給水栓）
５０注湯路（分岐路）
６２主開閉切換弁
６３副開閉切換弁
６４負圧破壊弁
６５圧力キャンセル弁
６６第１の弁軸（弁軸）
６７第２の弁軸
６８電動モータ（駆動手段）
７１第１カム部材
７２第２カム部材
７３，７４戻しバネ
９１，９２電磁式駆動手段（駆動手段）
６８１回転作動軸[0001]
BACKGROUND OF THE INVENTION
In the present invention, purified water supplied directly from a water supply or indirectly from a water receiving tank by pumping can be directly or indirectly injected into a storage tank open to the atmosphere through a branch path, and negative pressure is generated on the side of the purified water supply path. The present invention relates to a negative pressure breaker that is used to destroy (eliminate) the negative pressure and prevent backflow from the storage tank side to the purified water supply path.
[0002]
[Prior art]
Conventionally, as this kind of negative pressure breaking device, for example, a device installed in a hot water supply device is known. This hot water supply device supplies hot water to a hot water tap or water tap of a kitchen or the like by a hot water supply circuit or a water supply circuit as a purified water supply path through which purified water is supplied, while supplying the hot water to a storage tank that is open to the atmosphere such as a bathtub or a washing tub. Hot water or water can be poured directly or indirectly through a pouring channel (branch channel) or a water channel (branch channel) branched from a circuit or a water supply circuit. A negative pressure breaker is installed in the waterway. Such a negative pressure breaking device is used in a hot water supply circuit or a water supply circuit to which tap water (purified water) is supplied, for example, when a negative pressure occurs due to a water cut or a power failure on the tap water supply side. It is provided to prevent the occurrence of a situation in which hot water in a storage tank such as a tank flows backward and flows into the hot water supply circuit or the water supply circuit, that is, into the purified water supply path. The circuit and the storage tank are connected to each other in such a manner that they can be cut while pouring, pouring and shutting off are possible. In other words, a negative pressure breaker is installed to prevent the occurrence of a situation where hot water in a bathtub or washing tub, which is miscellaneous water, flows back into the hot water supply circuit or water supply circuit filled with purified water. ing. A conventional negative pressure breaker for realizing this backflow prevention performance will be described based on an example installed in the hot water supply apparatus 10 shown in FIG.
[0003]
This hot water supply apparatus 10 is an example of a hot water heater-equipped bath pot that can pour hot water into the bathtub 3 as a storage tank. That is, a hot water supply path 50 is branched from a downstream of a flow rate adjustment valve (water quantity servo valve) 30 provided on the hot water supply side of the hot water supply circuit 2, and communicates with the hot water supply circuit 2 and the bathtub 3 via the hot water supply path 50. The recirculation circuit 4 thus connected is connected to the tub 3 so that pouring or pouring (hereinafter, both are simply referred to as “pouring”) is possible. Then, a negative pressure breaking device 5 is arranged in this order from the upstream side to the vacuum breaker (negative pressure breaking valve) 52, the pouring electromagnetic valve 53, and the two-stage check valves 54, 55 with respect to the pouring passage 50. Is intervening. Reference numeral 51 denotes a pouring flow sensor for detecting the pouring flow rate.
[0004]
The vacuum breaker 52 described above sucks outside air (air) when a predetermined negative pressure is generated in the circuit and cancels (breaks) the negative pressure state. The pouring solenoid valve 53 switches the pouring passage 50 to open and close. In addition, the two-stage check valves 54 and 55 are closed by receiving the feed water pressure and allowing the flow in the pouring direction (forward direction) while eliminating the feed water pressure. The spring is restored to prevent the flow in the reverse direction.
[0005]
More specifically, the vacuum breaker 52 is normally kept closed by the water supply pressure in the pouring channel 50 in a state where the valve body is pressed against the valve seat by a spring, while a predetermined negative pressure is applied to the circuit. When acted, the valve element opens against the spring and sucks air into the circuit to eliminate the negative pressure. That is, the vacuum breaker 52 is configured by a pressure balance type that receives a supply water pressure and is maintained in a closed state and receives a negative pressure to open, and the spring has a predetermined negative pressure (set intake operating pressure). An initial urging force is applied to the valve body so as to start the intake operation due to the occurrence of.
[0006]
Further, the hot water solenoid valve 53 is constituted by a pilot type diaphragm valve, and is maintained in a closed state by a water supply pressure on the hot water supply circuit 2 side. That is, even when a relatively high supply water pressure is applied during the opening / closing operation, the valve can be opened or closed with a relatively light operating force, and the valve closing state can be reliably maintained. That is, a diaphragm chamber is defined on one side across a flexible diaphragm valve that is a valve body, while the outer side is defined by a cylindrical valve seat on the other side and communicates with the hot water supply circuit 2. The side communicates with the bathtub 3 side. When the diaphragm valve is pressed against the tip of the valve seat, the hot water supply circuit 2 side and the bathtub 3 side are shut off, that is, the valve closed state. In this valve closed state, the hot water supply circuit 2 side passes through the bleed hole. The water supply pressure is bleed into the diaphragm chamber, and this water supply pressure acts on the diaphragm valve as a valve closing maintaining pressure. Therefore, the higher the feed water pressure, the higher the pressure is pushed toward the valve closing side and the higher the sealing performance is. On the other hand, at the time of pouring, the electromagnet is energized to open the center hole at the center of the diaphragm valve and to connect the diaphragm chamber and the valve seat inner peripheral side (tub 3 side) to open the diaphragm valve.
[0007]
Here, in the case where the negative pressure is generated, each set from the water supply source water supply side (primary water supply side) where the water supply pressure (positive pressure) is originally acting, from the water supply source water supply cutoff, the water receiving tank, etc. When pumps are pumped to the upper floors of a house (apartment, etc.), a pump stop due to a power failure, etc. may cause the pressure on the primary side of the water supply to drop, creating negative pressure.
[0008]
[Problems to be solved by the invention]
Incidentally, in the negative pressure breaking device 10 as described above, the reason why the pouring electromagnetic valve 53 constituted by a pilot type diaphragm valve is employed as an open / close switching valve for switching pouring or shutting off of the pouring passage 50 is employed. The hot water supply passage 50 having a pressure difference between the relatively high water supply pressure on the side of the pouring circuit 2 and the almost atmospheric pressure state on the side of the bathtub 3 is switched between the pouring (communication) and the shut-off. This is because the valve can be opened / closed with a relatively light operating force even under the action, and a high valve closing maintenance performance (closed sealing performance) can be exhibited using the water supply pressure.
[0009]
However, the presence of the above-described electromagnetic solenoid 53 for pouring is contrary to the demand for downsizing of the entire negative pressure breaker 10, and the diameter of the pouring passage 50 itself is reduced in the diaphragm valve portion (the sectional area in the passage is reduced). This causes a problem that the discharge flow rate cannot be increased too much due to pressure loss during pouring. That is, the diaphragm valve has a considerably large diameter that covers and shields both the outer peripheral side communication part (hot water supply circuit 2 side) and the inner peripheral side communication part (tub 3 side) partitioned by a cylindrical valve seat. Is required. For this reason, the pouring solenoid valve 53 itself has to be quite large, which hinders downsizing of the entire apparatus. In addition, as described above, one diaphragm valve covers both the outer peripheral side and inner peripheral side communication portions, and the passages from both the hot water supply circuit 2 side and the bathtub 3 side need to communicate with this diaphragm valve. The path diameter or the cross-section in the passage must be made smaller than the other portions, which leads to an increase in flow resistance and a restriction on the discharge flow rate (pouring flow rate) during pouring.
[0010]
In addition, since the pouring electromagnetic valve 53 is configured to include a diaphragm valve, there is also a disadvantage that it is easily affected by pulsation from the upstream side. That is, the pulsation generated on the hot water supply circuit 2 side due to the sudden opening / closing operation of the hot water taps 26a, 26b may propagate, and the diaphragm valve of the hot water solenoid valve 53 may bounce. And with the occurrence of this bounce, water leaks from the upstream side to the downstream side.
[0011]
On the other hand, in the above-described pouring solenoid valve 53, a normally closed type in which the spring is returned to the closed state when not energized, so that even if a power failure occurs in the poured pouring state, There is also an advantage that the valve can be automatically closed.
[0012]
For this reason, instead of the pouring solenoid valve 53 employing the diaphragm valve, it is conceivable to employ an on / off switching valve that can forcibly switch the valve body by, for example, a motor or the like. When adopting, it is necessary to consider measures for power failure.
[0013]
Further, when the negative pressure breaking device 5 is constituted by employing the pouring electromagnetic valve 53 and the like as described above, the pouring electromagnetic valve 53 and the check valves 54 and 55 are only required to operate normally. If an abnormality such as a failure occurs, reverse inflow from the bathtub 3 side may occur due to the generation of negative pressure on the primary side of the water supply. That is, when the water injection solenoid valve 53 and the check valves 54 and 55 should be closed due to a failure or foreign matter biting (for example, in a steady state when the pouring is completed), they are not completely closed. In the case where a closing operation abnormality that remains open occurs, the negative pressure reaches the bathtub 3 side when the water supply primary side falls into a negative pressure state due to water breakage or the like. When the negative pressure is generated, the vacuum breaker 52 opens and starts sucking air to destroy the negative pressure. However, since the vacuum breaker 52 is a pressure balance type as described above, the start of the air suction operation is There is a delay with respect to the negative pressure generation time, and during that time, the negative pressure passes through the molten solenoid valve 53 and the check valves 54 and 55 in the abnormal state of the closing operation and reaches the bathtub 3 side. Will be invited.
[0014]
In order to cope with this, a motor that can be forced to open in a steady state and communicate with the atmosphere in the pouring passage downstream of the pouring solenoid valve, while being converted to a valve closing state during pouring. It is conceivable to achieve fail-safe by interposing drive type valve means. In other words, a vacuum breaker that can be forcibly switched between open and close is disposed at a downstream position of the pouring solenoid valve. However, when tap water (purified water) is supplied from the water receiving tank to the upper floors of high-rise housing (apartments, etc.) by pumping, when the negative pressure is generated due to the stoppage of the pump due to the occurrence of a power failure, the above motor drive If a predetermined operation cannot be performed due to a power failure even if a valve means of the type is interposed, it is considered that the negative pressure due to air suction cannot be eliminated and a back flow occurs. On the other hand, as a countermeasure against power failure, it may be possible to install in advance a standby power supply (for example, a capacitor having a large capacitance) that forcibly opens the motor-driven valve means in the event of a power failure. However, if such a spare power supply is also mounted, the cost of the entire apparatus will be greatly increased. In other words, since the motor-driven valve means normally rotates the valve shaft itself by rotating the motor to advance or retract the valve shaft, the valve shaft is driven to rotate from the closed state to the open state. Therefore, a considerable amount of rotation is required, and driving power energy capable of expressing such a large amount of rotation is required.
[0015]
Inconveniences such as the possibility of reverse inflow due to the above closed operation abnormality or power failure, the water injection connection target is not a bathtub but connected to a washing tub as a storage tank from a hot water supply circuit or a water supply circuit so that automatic pouring is possible This also occurs in some cases. Furthermore, even when a storage tank that is open to the atmosphere is connected so that water can be injected through a branch path branched from a purified water supply path to which purified water is supplied based on a predetermined water supply pressure, there is a disadvantage such as the possibility of reverse inflow as described above. It can occur as well. In addition, if the target of water injection / pour water is a storage tank that is open to the atmosphere, and the hot water in the water injection / poured storage tank is used for bathing or washing, etc., it will be treated as miscellaneous water, ensuring reverse inflow. Need to be prevented.
[0016]
The present invention has been made in view of the circumstances as described above. The purpose of the present invention is to prevent backflow due to negative pressure destruction while allowing water to be poured from the purified water supply path side into a storage tank open to the atmosphere. It is an object of the present invention to provide a negative pressure breaking device capable of reliably preventing the occurrence of reverse inflow from the storage tank side without causing an increase in size or an increase in water injection resistance. In addition, it is an object of the present invention to reliably prevent the occurrence of reverse inflow even when a valve closing operation abnormality or a power failure occurs, and to realize it without causing an increase in cost.
[0017]
[Means for Solving the Problems]
In order to achieve the above object, instead of a conventional opening / closing switching valve having a diaphragm valve, an opening / closing switching valve that can be forcibly opened / closed by a driving means such as a motor is adopted. By making it possible to install a pressure cancel valve that cancels the water supply pressure that becomes the resistance of switching, it is possible to realize reliable switching of water injection or shut-off with a relatively light driving force while eliminating the disadvantages associated with the adoption of a diaphragm valve It is a thing.
[0018]
Specifically, in the invention according to claim 1, a storage tank that is open to the atmosphere is connected to a purified water supply path that is supplied with purified water under a predetermined water supply pressure so that water can be injected through a branch path that branches from the purified water supply path. The following specific items are provided for a negative pressure breaking device that is interposed in the branch path and breaks the negative pressure while enabling the water injection switching between the purified water supply path and the storage tank. That is, a main opening / closing switching valve that is inserted in the branch path and performs switching switching of water injection or shutoff, and a pressure cancellation valve that cancels out the internal pressure from the purified water supply path acting on the upstream side of the main opening / closing switching valve, A drive-type sub-open / close switch valve that is interposed in a downstream position of the main open / close switch valve and performs switching of water injection or shut-off, and communicated with a position between the sub-open / close switch valve and the main open / close switch valve. The main opening / closing switching valve is connected to the main open / close switching valve and the pressure canceling valve, and is connected to the main opening / closing switch by the forward / backward driving force. And a valve shaft for switching between opening and closing of the valve.
[0019]
In addition, the above-mentioned “reservoir open to the atmosphere” is a storage tank in which the hot water stored by receiving water injection forms a free water surface, and atmospheric pressure acts on the free water surface. As the “purified water supply channel”, for example, a bathtub that receives pouring for bathing (water filling) for bathing from a hot water supply circuit, or pouring for hot water for washing hot water (water filling) from the hot water supply circuit. The washing tub etc. which receive are mentioned (the same also in the following claims). Further, the above-mentioned opening / closing switching of the main opening / closing switching valve is performed when both the valve shaft is actively driven on one side and the other side in the forward / backward direction to perform both opening and closing with a driving force, for example, The valve opening is switched by the driving force to one side of the valve shaft in the forward / backward direction, and the other side of the forward / backward direction is allowed to be closed by releasing the driving force, while the switching to return to the closed state itself is by spring return. Any one of the cases where it is performed may be adopted.
[0020]
According to the first aspect, when the valve shaft receives the forward / backward driving force to open / close the main on / off switching valve, the internal pressure from the purified water supply path side acting on the main on / off switching valve and serving as the on / off switching resistance is reduced. The pressure cancellation valve coupled to the same valve shaft also acts and cancels out in the same manner as the main opening / closing switching valve. In other words, since the internal pressure that becomes a resistance is canceled when the main on / off switching valve is switched, the forward / backward driving force for the on / off switching does not overcome the water supply pressure from the purified water supply path side, but just the main on / off switching valve. A light driving force sufficient to operate the valve body is sufficient. For this reason, even if a conventional diaphragm valve is not used as the main switching valve, it is possible to use a simple type that directly opens and closes the passage by a valve body, or to supply water to a branch passage where a considerably high water supply pressure acts from the purified water supply passage side or It is possible to reliably perform switching with a light driving force. As a result, as compared with the case of using the diaphragm valve type, the entire device is made compact, and the passage diameter of the branch passage is not reduced, and the flow resistance is not increased. In addition, it is possible to avoid inconvenience caused by the occurrence of the bounce of the diaphragm valve.
[0021]
In addition, a negative pressure release valve that is driven and can be forcibly switched over is arranged at the downstream position of the main switching valve. Therefore, the main switching valve is closed and shut off. When the negative pressure release valve is forcibly switched to the open state in the steady state, a closed operation abnormality that is not completely closed due to foreign matter biting into the valve such as the main on-off switching valve can be obtained. Even if it occurs, if the purified water supply passage side becomes negative pressure, air is immediately sucked from the negative pressure destruction valve in the above-described valve open state. Thereby, the said negative pressure is eliminated and generation | occurrence | production of the reverse inflow from the storage tank side to the purified water supply channel side is also prevented reliably. In the above-mentioned steady state, if the main on / off switching valve is normally closed without switching operation, even if negative pressure is generated on the purified water supply path side, Since it is reliably shut off, no backflow from the storage tank side occurs.
[0022]
The fact that the above-described main open / close switching valve can be opened / closed with a light driving force even when a high feed water pressure is applied exhibits excellent significance in measures against a power outage. That is, as a countermeasure when the purified water supply passage side falls into a negative pressure state due to the occurrence of a power failure before the main opening / closing switching valve is closed (steady state), the valve shaft is driven forward and backward to drive the main shaft. A standby power supply is provided for supplying drive power to the valve shaft drive means for switching the open / close switching valve to close, and in the event of a power failure, the valve shaft is operated by the power supply from the standby power supply to switch the main open / close When the valve is closed, the required capacity required for the standby power source (for example, an electrolytic capacitor or a primary battery or a secondary battery) can be made extremely small.
[0023]
That is, a relatively high water supply pressure from the purified water supply passage acts as an internal pressure on the main open / close switching valve, and the valve shaft is moved forward and backward by the rotational drive of the driving means to perform the valve closing switching. Therefore, a considerably high operating torque is required due to the resistance due to the water supply pressure. On the other hand, in the case of claim 1, since the resistance acting on the main switching valve is canceled by the pressure cancellation valve, the operating torque required for switching the closing of the main switching valve is greatly reduced. Become. For this reason, it becomes possible to greatly reduce the driving power energy for switching back to the steady state at the time of a power failure. Therefore, even if a spare power supply is mounted, the capacity can be greatly reduced. It becomes possible to prevent the occurrence of reverse inflow caused by the occurrence of a power failure by switching the main opening / closing switching valve without causing a significant increase in cost.
[0024]
Here, as a configuration for applying the forward / backward driving force to the valve shaft, a driving means for generating a reciprocating driving force such as a cylinder is connected to one or both ends of the valve shaft, or the rotational driving force of the motor is reciprocated. Various things can be adopted, such as transmission to the valve shaft after conversion, or advancement and retraction by rotating the valve shaft itself by means of a motor such as bolts and nuts. Since the force may be relatively light, for example, the following configuration may be adopted in addition to pushing or pulling the valve shaft by electromagnetic driving means using an electromagnet (electromagnetic coil).
[0025]
That is, the cam member according to claim 1, further comprising a driving means for applying a forward / backward driving force to the valve shaft, wherein the cam member is connected to the rotational operation shaft by transmitting the rotational driving force to the rotational operation shaft. The valve shaft is arranged so as to be orthogonal to the rotation operation shaft, and the main opening / closing switching is performed by receiving a pressing force from one end to the forward / backward direction side by the forward / reverse one side rotation of the cam member. While the valve is switched from the steady state in the closed state to the water injection state in the valve open state, when the pressing force is released by the forward / reverse other side rotation of the cam member, the water injection state is returned to the steady state and the spring is returned by the spring. A configuration is defined (claim 2). Here, as the “driving means”, an electric motor (for example, a servo motor or a stepping motor) may be used, or a hydraulic motor controlled by energization may be used.
[0026]
In the case of this second aspect, in addition to reducing the operating torque of the driving means by the pressure cancel valve, the camshaft is used for the advance / retreat operation of the valve shaft. The required amount of rotation can be greatly reduced as compared with the case where the valve shaft itself is moved forward and backward. For example, the rotation amount can be greatly reduced from 315 degrees when the valve shaft itself is rotated to 10 to 20 degrees when the cam member is rotated to realize the same advance / retreat amount. As a result, the power energy for driving for the above-mentioned return switching can be greatly reduced, so even when a standby power supply for supplying power for switching back to the steady state is installed as a countermeasure at the time of power failure Therefore, it is possible to avoid the occurrence of backflow at the time of a power failure while realizing a significant reduction in the required capacitance of the standby power supply and avoiding a significant increase in cost. Note that a speed reduction mechanism may be interposed between the driving means and the rotation operation shaft.
[0027]
In the invention which concerns on Claim 3, the storage tank open | released to air | atmosphere is connected to the said branched path through the branch path branched from this purified water supply path with respect to the purified water supply path supplied with purified water under a predetermined water supply pressure. The following specific matters are provided for a negative pressure breaking device that is interposed and breaks the negative pressure while enabling water injection switching between the purified water supply path and the storage tank.
[0028]
That is, a main opening / closing switching valve that is inserted in the branch path and performs switching switching of water injection or shutoff, and a pressure cancellation valve that cancels out the internal pressure from the purified water supply path acting on the upstream side of the main opening / closing switching valve, A sub-opening / closing switching valve that is interposed downstream of the main opening / closing switching valve and performs switching of water injection or shut-off, and is disposed in communication with a position between the sub-opening / closing switching valve and the main switching valve. A negative pressure release valve, which is connected to the atmosphere side to switch between open and close, and the main open / close switching valve and the pressure cancellation valve are connected to each other and receive the driving force in the forward / backward direction to open / close the main open / close switching valve. The first valve shaft that performs switching, the sub open / close switching valve, and the negative pressure release valve are coupled to each other, and the open / close switching of both the sub open / close switching valve and the negative pressure release valve is performed in response to a driving force in the forward / backward direction. And a second valve stem Then, as the second valve shaft, the auxiliary open / close switching valve is switched from the closed state to the open state by receiving the forward / backward driving force from the driving means and operating in the forward / backward direction side, and the negative pressure breaking valve The valve is switched from the open state to the closed state to switch the sub open / close switching valve and the negative pressure release valve from the steady state to the water injection state, while operating in the forward / backward direction to switch from the water injection state to the steady state. To return.
[0029]
According to the third aspect of the present invention, since the main open / close switching valve is provided with the pressure canceling valve, all of the effects of the first aspect can be obtained, and the secondary open / close switching can be performed by moving the second valve shaft forward and backward. It becomes possible to perform opening / closing switching of both the valve and the negative pressure release valve. By controlling the forward / backward drive for the first and second valve shafts, it is possible to perform the open / close switching control of all the valves. It should be noted that the forward / backward driving force is applied to each of the first and second valve shafts even if the driving means is individually provided and the driving force is individually applied to each valve shaft. Either method can be adopted even if a driving force is applied to the shaft.
[0030]
In particular, the advance / retreat driving force can be applied to the second valve shaft as follows. That is, a driving means for applying a driving force to one side in the forward / backward direction with respect to the second valve shaft, and a return spring for applying a returning force to the other side in the forward / backward direction with respect to the second valve shaft, The sub-open / close switching valve and the negative pressure release valve are switched from the steady state to the water injection state by receiving the driving force from the driving means and driving the second valve shaft to one side in the forward / backward direction. When the maintenance force of the water injection state due to is eliminated, the auxiliary open / close switching valve and the negative pressure release valve are switched from the water injection state to the steady state and returned by receiving a return force from the return spring ( Claim 4). In other words, the opening / closing switching of the sub open / close switching valve and the switching switching of the negative pressure release valve are performed by the driving force from the driving means, while the reverse switching of the reverse opening / closing switching valve and the open switching of the negative pressure release valve are returned. This is done by a spring. In this case, the drive means is an electromagnetic type that exerts a driving force by energization, or a rotation drive type that rotates by energization and exhibits a driving force but can be stepped out when de-energized (for example, a stepping motor) If this is the case, it is possible to convert the negative pressure release valve to a state that can prevent the occurrence of backflow by automatically switching the negative pressure release valve with a return spring without the need for power supply such as a standby power supply when a power failure occurs become. The return force by the return spring may be applied directly to the second valve shaft, or may be applied indirectly via a sub-open / close switching valve or a negative pressure release valve.
[0031]
Further, in the forward / backward operation of the second valve shaft in the above-described third or fourth aspect, it is preferable to further add the following configuration. That is, the second valve shaft switches the negative pressure release valve from the open state to the closed state when switching from the steady state to the water injection state by driving the second valve shaft to one side in the forward / backward direction. The sub-open / close switching valve and the second valve shaft are related so that the sub-open / close switching valve receives the operating force from the second valve shaft and starts the valve opening operation from the closed state after a stroke of (Claim 5). That is, as the operation timing of the negative pressure release valve and the auxiliary on / off switching valve when the second valve shaft is driven to one side in the forward / backward direction, the auxiliary on / off switching valve is opened after the negative pressure release valve is closed. It is to set. That is, when switching from the steady state to the water injection state is started by driving the second valve shaft toward one side in the forward / backward direction, the negative pressure release valve is changed by the previous stroke from the start of driving of the second valve shaft. The valve is switched to the closed state by receiving the operating force from the second valve shaft, and then the sub-opening / closing switching valve receives the operating force from the second valve shaft and starts the valve opening operation by the subsequent stroke. It will be switched to. Conversely, when the second valve shaft is returned to the other side in the forward / backward direction, the auxiliary switching valve first returns from the open state to the closed state, and after returning to the closed state, the negative pressure release valve Starts to open from the closed state and is switched to the open state.
[0032]
Furthermore, in the advance / retreat operation of the first and second valve shafts according to any one of claims 3 to 5, it is preferable to add the following configuration. That is, as a timing for applying a driving force to one side in the forward / backward direction with respect to the first valve shaft and the second valve shaft, the driving force is first applied to the second valve shaft, and the negative pressure breaking valve and the auxiliary opening / closing The switching valve is switched from the steady state to the water injection state, and after this is completed, a driving force is applied to the first valve shaft, and the main switching valve is changed from the steady state in the closed state to the water injection state in the open state. Is set so as to be switched (Claim 6). That is, the operation timing at the time of switching from the steady state which is a non-water injection state to the water injection state is clarified. In this case, after the negative pressure release valve is closed and the auxiliary on / off switching valve is opened, the main on / off switching valve is opened and water injection is performed. Conversely, when switching from the water injection state to the steady state, the first valve shaft is driven and the main on / off switching valve is closed and shut off, and then the second valve shaft is driven. Then, the sub open / close switching valve may be closed to open the negative pressure release valve.
[0033]
In order to realize the operation timing according to the sixth aspect of the invention, the first and second valve shafts may be driven by individual drive means, and the operation timing of each drive means may be controlled. In the case where both the first and second valve shafts are driven by a common driving means, it is possible to adopt the following configuration. That is, a common drive unit that applies a driving force to each of the first valve shaft and the second valve shaft is provided, and the drive unit is orthogonal to the first and second valve shafts. And a rotary operating shaft that receives rotational driving force from the driving means, and is oscillated and rotated by the rotational driving of the rotary operating shaft to apply an operating force in the advancing / retreating direction to the first and second valve shafts. A first and second pair of cam members for transmission are provided (claim 7). Thereby, the operation timing according to claim 6 can be easily realized by one driving means. That is, the pair of cam members are changed in shape or have the same shape so that the operation timing of the pair of cam members with respect to the first and second valve shafts is the driving force application timing of claim 6. However, if the phase difference is added and coupled to the rotary operation shaft, the sixth aspect of the present invention can be easily realized even if the driving force is transmitted from the common driving means.
[0034]
Further, as described in claim 7, both the first and second valve shafts are advanced and retracted by cam drive so that not only the main open / close switching valve but also the negative pressure breaking valve and the sub open / close switching valve can be switched. The necessary amount of rotation of the required drive means can be made extremely small, and a countermeasure in the event of a power failure can be easily realized without incurring a significant cost increase. That is, when a power failure occurs, the drive means is rotated by power supply from a standby power supply to close the sub-open / close switching valve and open the negative pressure release valve. ) Required capacitance can be made extremely small, and the cost required for the standby power supply can be kept low.
[0035]
The auxiliary open / close switching valve according to any one of claims 1 to 7 is provided with a spring that biases the valve body toward the valve closing side, and the valve body of the auxiliary open / close switching valve as the spring is opened to the valve opening side. You may make it set so that it may have the spring load which can overcome the negative hydraulic head pressure from the downstream which attracts | sucks, and can maintain a valve closing state (Claim 8). By doing so, the storage tank is installed at a lower position (for example, the downstairs position) than the purified water supply path side, and the negative water head pressure acts on the sub open / close switching valve due to the water column in the pipe to the storage tank. Even so, it is possible to overcome the negative water head pressure and to reliably maintain the auxiliary open / close switching valve in the closed state. In addition, you may make it combine said "spring" with the return spring in Claims 4-7.
[0036]
Furthermore, a specific object to which the negative pressure breaking device according to any one of claims 1 to 8 can be applied is as follows. That is, as the purified water supply path, a hot water supply circuit that receives purified water and is heated by a heating source to supply hot water to the hot water tap side, or a water supply circuit that receives purified water and supplies water to the water tap side, this hot water supply circuit or water supply circuit On the other hand, a storage tank open to the atmosphere is connected to be able to pour hot water or water through a branch passage (claim 9). In this case, in addition to the hot water poured when the heating source of the hot water supply circuit is heated and operated, there is water injection when the hot water is poured while the heating source is not heated.
[0037]
【The invention's effect】
As described above, according to the negative pressure breaker of any one of claims 1 to 9, since the pressure cancellation valve is attached to the main switching valve, the switching of the main switching valve is switched. In this case, it is possible to cancel the water supply pressure from the clean water supply path side acting as a resistance by canceling. For this reason, the opening / closing switching of the main switching valve can be realized with an extremely light driving force. As a main switching valve, instead of the conventional diaphragm valve, a simple type that opens and closes the passage directly by a valve body Can be adopted. As a result, there is a disadvantage in using the diaphragm valve type described above, that is, the entire apparatus is enlarged, the passage diameter of the branch path is narrowed, the flow resistance is increased, and the diaphragm valve bounces. All the disadvantages of causing inconveniences can be eliminated, the entire apparatus can be made compact, and efficient water injection from the purified water supply path side to the storage tank side can be realized.
[0038]
Further, even when a standby power source for closing the main switching valve is provided as a countermeasure when a power failure occurs, the internal pressure acting as an operating resistance on the main switching valve is offset by the pressure cancel valve. Therefore, the required operating torque for driving the valve shaft can be greatly reduced, and as a result, the driving power energy required for the standby power source can be greatly reduced. For this reason, even if a standby power supply is installed, the required electrostatic capacity can be greatly reduced, and the main open / close switching valve is automatically closed without causing a significant increase in cost. Reverse inflow can be prevented
In addition, a negative pressure release valve that can be forcibly opened by the operation of the valve shaft that receives the forward / backward drive force is provided, so the negative pressure release valve is forcibly opened during normal operation after the completion of water injection. By doing so, even if all of the main open / close switching valve and the sub open / close switching valve are abnormally closed, if the purified water supply passage falls into a negative pressure state, the air is discharged from the open negative pressure destruction valve. Is sucked in immediately and the negative pressure can be eliminated, and the occurrence of reverse inflow from the storage tank side can be reliably prevented.
[0039]
In particular, according to the second aspect, in addition to reducing the operating torque, the camshaft is used to advance and retract the valve shaft. Therefore, when the power failure occurs, the forward / reverse other side rotation for automatically closing the main open / close switching valve is performed. The required amount of rotation can be greatly reduced compared to the case where the valve shaft itself is operated to the other side in the forward / backward direction. As a result, the driving power energy for the automatic valve closing described above can be greatly reduced, and even if a standby power supply is installed as a countermeasure against a power failure, the required electrostatic capacity of the standby power supply can be reduced. It is possible to avoid backflow when a power failure occurs while further reducing the capacity and further suppressing an increase in cost.
[0040]
According to the third aspect of the present invention, it is possible to perform the open / close switching control of all the valves by controlling the forward / backward drive with respect to the first and second valve shafts.
[0041]
According to the fourth aspect of the present invention, the driving means for driving the second valve shaft back and forth in the third aspect is an electromagnetic type that exerts a driving force by energization, or a non-rotating device that exhibits a driving force by rotating by energization. While it is possible to adopt a rotary drive type that can be stepped out when energized, even if these are adopted, the return pressure spring does not require a power supply such as a backup power source in the event of a power failure Thus, the valve can be automatically switched to open and converted into a state in which the backflow can be prevented.
[0042]
According to claim 5, when the second valve shaft in claim 3 or 4 is driven to one side in the forward / backward direction, the sub open / close switching valve is opened after the negative pressure release valve is reliably closed. As described above, the operation timing of the negative pressure release valve and the sub open / close switching valve can be set.
[0043]
According to claim 6, as the switching from the steady state to the water injection state by the advance and retreat operation of the first and second valve shafts in any one of claims 3 to 5, the negative pressure breaking valve and the auxiliary After switching the open / close switching valve from the steady state to the water injection state, the main open / close switching valve can be switched from the steady state in the closed state to the water injection state in the open state.
[0044]
According to the seventh aspect, the operation timing in the specific order according to the sixth aspect can be easily realized even when the forward / backward driving force is applied to the first and second valve shafts by the common driving means. Moreover, since the advance / retreat driving force is applied by the cam drive, the required amount of rotation of the drive means required for opening / closing switching of not only the main opening / closing switching valve but also the negative pressure release valve and the auxiliary opening / closing switching valve is extremely reduced. Will be able to. For this reason, even when the drive means is rotated by power supply from a standby power supply as a countermeasure when a power failure occurs, the sub open / close switching valve is closed and the negative pressure release valve is opened, The required electrostatic capacity required for the standby power supply can be made extremely small, and the backflow caused by the generation of negative pressure in the event of a power failure while keeping the cost required for the standby power supply low and avoiding significant cost increases Occurrence can be avoided.
[0045]
According to claim 8, even if the storage tank is installed at a lower position than the purified water supply path side and a negative water head pressure acts on the sub open / close switching valve due to the water column in the pipe to the storage tank, The sub-open / close switching valve can be reliably maintained in the closed state by overcoming the negative water head pressure.
[0046]
According to the ninth aspect, it is possible to specify a configuration suitable as a specific target to which the negative pressure breaking device according to any one of the first to eighth aspects is applied.
[0047]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0048]
<First Embodiment>
FIG. 1 shows a hot water supply device 1 to which a negative pressure breaking device 6 according to a first embodiment of the present invention is applied. That is, this embodiment is an application of the present invention in the case where it is possible to pour and pour water into the bathtub 3 as a storage tank through a hot water supply path (branch path) 50 branched from the hot water supply circuit 2 as a purified water supply path.
[0049]
The hot water supply device 1 includes a hot water supply circuit 2 that realizes a hot water supply function, a forced circulation reheating circuit 4 that realizes a reheating function of hot water in the bathtub 3, the hot water supply circuit 2, and a recirculation circuit 4. And a pouring passage 50 for pouring or pouring water into the bathtub 3 (hereinafter simply referred to as “pouring”).
[0050]
The hot water supply circuit 2 heats water (purified water) introduced from a water supply path 21 connected to a water pipe by heat exchange heating with the combustion heat of the combustion burner 23 in a hot water supply side heat exchanger 22, and hot water after heating. The hot water is supplied to the hot-water taps 26a, 26b at the downstream end through the hot water outlet 24 and the hot water supply path 25. Here, the heat exchanger 22 and the combustion burner 23 arranged in the combustion can body constitute a heating source. A bypass passage 27 is provided between the water supply passage 21 and the hot water supply passage 24, and temperature adjustment to the set temperature is performed by water mixing adjustment control by the adjustment valve 27a. The hot-water tap 26a is a currant disposed in a kitchen or the like, and the hot-water tap 26b is a shower currant installed in a bathroom or a washstand.
[0051]
The water supply passage 21 is provided with an incoming water flow rate sensor 28 and an incoming water temperature sensor 29. In addition, a hot water supply temperature sensor 31 for detecting the temperature of hot water supplied to the hot water tap 26 or the pouring passage 50 and a flow rate adjusting valve 30 are arranged in this order from the upstream side. The controller 11 performs hot water supply control for controlling the combustion of the combustion burner 23 so that the hot water supply temperature and the pouring temperature become a predetermined set temperature. In the controller 11, the water flow rate sensor 28, the incoming water temperature sensor 29, and the hot water supply are mainly used. The hot water supply control is performed based on each detection value from the temperature sensor 31.
[0052]
The recirculation circuit 4 includes a circulation path 43 including a return path 41 and an outward path 42 respectively connected to the bathtub 3, and is returned to the bath-side heat exchanger 45 from the return path 41 by the operation of the circulation pump 44. The hot and cold water in the bathtub 3 is heat-exchanged and heated by the combustion heat of the combustion burner 46, and the heated hot water is supplied again into the bathtub 3 through the outgoing path 42 so as to follow it.
[0053]
The return path 41 includes a circulation pump 44 in order from the upstream side in the circulation direction of the circulating hot water, a water flow switch 48 in which a flap is opened by the passage of the circulation flow and an ON command for circulation determination is output, and a bath side from the bathtub 3 A return temperature sensor 49 for detecting the temperature of the circulating hot water returned to the heat exchanger 45 is provided. Further, a water level sensor 47 that detects the water level of the bathtub 3 by detecting the water pressure is disposed at the downstream end side position of the pouring channel 50 described later. Then, the hot water control up to a predetermined water level is performed by the controller 11 based on the detection value from the water level sensor 47, and the hot water temperature in the bathtub 3 at the time of reheating based on the detection value from the return temperature sensor 49. Thus, the controller 11 performs reheating control up to a predetermined temperature, and the controller 11 determines whether or not the circulation operation is normal in the reheating control based on the output signal from the water flow switch 48. Become.
[0054]
The pouring channel 50 has an upstream end branched from a downstream position of the flow rate adjusting valve 30, and a downstream end positioned at any position of the circulation path 43 (in FIG. 1, a position downstream of the circulation pump 44 of the return path 41. The hot water from the hot water supply circuit 2 is replenished through the pouring channel 50 and flows into the circulation circuit 4 to be poured into the bathtub 3. In addition, as shown in detail in FIG. 2 or FIG. 2 shows a steady state (hereinafter also referred to as “steady time”) in which the pouring passage 50 is shut off after the pouring is completed and the next pouring is waited for, and in FIG. 3, the pouring at the time of pouring is shown. The state is illustrated.
[0055]
That is, the negative pressure breaking device 6 includes a check valve 61 that is interposed in order from the upstream side with respect to the pouring passage 50 branched from the downstream position of the flow rate adjustment valve 30, a main on-off switching valve 62, And a sub open / close switching valve 63. In addition, the negative pressure breaking device 6 includes a negative pressure breaking valve 64 disposed in communication with the pouring passage 50 at an intermediate position between the main opening / closing switching valve 62 and the sub opening / closing switching valve 63; And a pressure cancellation valve 65 for canceling out the internal pressure from the pouring circuit 2 acting on the upstream side of the main switching valve 62. The pressure cancellation valve 65 and the main on / off switching valve 62 are respectively coupled to a common first valve shaft 66, while the negative pressure release valve 64 and the sub on / off switching valve 63 are connected to a common second valve shaft 67. Are coupled to each other. The first valve shaft 66 and the second valve shaft 67 are respectively connected to a tongue-shaped first and second cam members 71 and 72 from an electric motor (for example, a servo motor) 68 as a common driving means. By receiving the forward / backward operating force, the main on / off switching valve 62, the sub on / off switching valve 63, and the negative pressure release valve 64 are switched to a predetermined state.
[0056]
Hereinafter, each component of the negative pressure breaker 6 will be described in detail. In the figure, for example, 51 is a pouring flow rate sensor that includes a rotatable impeller and detects the pouring flow rate, and this pouring flow rate sensor 51 is not an essential element as a negative pressure breaking device.
[0057]
The check valve 61 opens upon receiving the supply water pressure at the time of pouring and allows only the flow to the bathtub 3 side. On the other hand, when the supply water pressure is released, the check valve 61 is returned to the closed state by the spring 611. It has the structure maintained by this. If the main open / close switching valve 62 is in the closed state, the check valve 61 is in the closed state even if the supply water pressure is received from the upstream side by a fluid such as water sealed between the two. When the main opening / closing switching valve 62 is opened and the downstream side is opened, the valve is opened by the feed water pressure.
[0058]
The first valve shaft 66 and the second valve shaft 67 are arranged in parallel to each other so as to be orthogonal to the rotational operation shaft 681 of the electric motor 68, and their forward and backward directions (the vertical direction in FIGS. 2 and 3). Is supported by the housing so as to be movable. The valve shafts 66 and 67 are respectively fixed to the pins 66a and 67a for receiving or releasing the pressing force in the forward / backward direction from the cam members 71 and 72, and the forward and backward movement of the valve shafts 66 and 67. It is comprised from the shaft bodies 66b and 67b extended in a direction. Then, the first cam member 71 (see also FIG. 4) is rotated by a predetermined amount in the counterclockwise direction from the steady state of FIG. Is moved downward (actuated to one side in the forward / backward direction) to switch to the pouring state of FIG. 3 in which the main opening / closing switching valve 62 is opened, while the first cam member 71 is moved clockwise from the pouring state. The first valve shaft 66 is compressed and restored by a return spring 73 (to be described later) while releasing the pressing force against the first valve shaft 66 by being reversely rotated by the predetermined amount (forward / reverse rotation driving). Accordingly, the main opening / closing switching valve 62 is closed back and switched back to the steady state of FIG.
[0059]
On the other hand, when the second cam member 72 is rotated by a predetermined amount in the counterclockwise direction from the steady state of FIG. 2 (forward / reverse one-side rotational drive), the second valve shaft 67 is moved forward (forward / backward direction). 3), the sub-opening / closing switching valve 63 is opened and the negative pressure release valve 64 is closed to switch to the pouring state of FIG. 3, while the second cam member 72 is rotated clockwise from the pouring state. The second valve shaft 67 is compressed and restored by a return spring 74 (to be described later) while releasing the pressing force against the second valve shaft 67 by being reversely rotated by the predetermined amount (forward / reverse rotation). The force is reversely moved upward (actuated to the other side in the forward / backward direction) to switch back to the steady state of FIG. 2 in which the sub open / close switching valve 63 is closed and the negative pressure release valve 64 is opened.
[0060]
As shown in FIG. 4, the first cam member 71 and the second cam member 72 are configured so that the second cam is rotated when the rotation operating shaft 681 of the electric motor 68 is rotated forward and backward (rotated counterclockwise). The member 72 is set so that the second valve shaft 67 is first pressed to advance, and then the first cam member 71 presses the first valve shaft 66 to advance.
[0061]
A main opening / closing switching valve 62 is fixed to the first valve shaft 66 at the tip position, and a pressure canceling valve 65 is fixed opposite to the upstream pressure receiving surface 621 of the main opening / closing switching valve 62. The pressure canceling valve 65 is prevented from moving toward the main opening / closing switching valve 62 by the stopper 651, while the pressure canceling valve 65 is moved away from the shaft 66b by connecting the small-diameter male screw portion on the base end side of the pin 66a. The pressure cancellation valve 65 is clamped by being screwed into the female screw portion, and is thereby blocked, whereby the first valve shaft 66 is fixed. A pouring passage 50 is defined between the pressure cancellation valve 65 and the main switching valve 62, and the upstream side pressure receiving pressure surrounded by the valve seat 622 of the main switching valve 62 as shown in FIG. The surface 621 and the opposing surface 652 of the pressure cancellation valve 65 are set to have substantially the same pressure receiving area. As a result, the internal pressure in the pouring channel 50 is applied to both the main opening / closing switching valve 62 and the pressure canceling valve 65 in opposite directions, and the main opening / closing switching valve 62 is advanced or retracted (open / close switching operation). The operating resistance pressure acting on the basis of the internal pressure is canceled.
[0062]
Further, a return spring 73 is stretched between the main opening / closing switching valve 62 and the housing, and the return spring 73 biases the first valve shaft 66 to the backward side (the other side in the forward / backward direction). While returning from the pouring state to the steady state, the main opening / closing switching valve 62 is maintained in the closed state.
[0063]
Note that the back side of the pressure cancel valve 65 communicates with the atmosphere through the through-hole 653, and the seal member 654 interposed between the housing cylinder formed by the housing has a viewpoint of reducing sliding resistance. A U-shaped ring or an X-shaped ring is adopted instead of the O-shaped ring (the U-shaped ring is shown in the figure).
[0064]
On the other hand, the valve body 641 of the negative pressure release valve 64 is supported so as to be relatively movable at an intermediate position of the second valve shaft 67, and the valve body 631 of the sub open / close switching valve 63 is supported so as to be relatively movable at the tip position. Has been. The valve body 641 of the negative pressure release valve 64 is blocked by the stopper 642 from moving toward the side close to the sub open / close switching valve 63 (one side in the forward / backward direction), while being biased toward the stopper 642 by the spring 643. Has been. Further, the valve element 631 of the sub open / close switching valve 63 is prevented from moving toward the side close to the negative pressure release valve 64 (the other side in the forward / backward direction) by the tip 671 of the second valve shaft 67, while the return spring 74 is biased toward the tip 671. The tip 671 constitutes a stopper, but a stopper may be provided separately instead of the tip 671. In addition, the spring 643 exhibits a maintenance force for maintaining the valve body 641 in a closed state in a pouring state described later, and the return spring 74 moves the second valve shaft 67 in the backward direction (the forward and backward direction, etc.). The valve body 631 of the sub open / close switching valve 63 is maintained in a closed state while switching from the pouring state to the steady state.
[0065]
In addition, the tip 671 of the second valve shaft 67 and the valve body 631 of the sub open / close switching valve 63 are in a steady state, that is, in a closed state, a predetermined clearance S in the forward / backward direction. ₁ (See FIG. 2) is set, and this gap S ₁ Is the forward / backward direction interval S between the valve body 641 of the negative pressure release valve 64 and the valve seat 644. ₂ Is set to be equal (or at least larger) to (S ₁ = S ₂ ). Then, the second valve shaft 67 is separated from the steady state by an interval S. ₁ When the forward operation is performed for the stroke corresponding to the above, the negative pressure release valve 64 is closed, and when the forward operation is performed further, the auxiliary opening / closing switching valve 63 is pushed by the tip 671 to start the valve opening operation, and the negative pressure release valve 64 is closed. Further S from time ₃ If the forward movement is performed by the overstroke of (see FIG. 3), the sub open / close switching valve 63 is spaced S. ₄ Will only open. Where S ₁ = S ₂ If so, S ₄ = S ₃ The total stroke of the second valve shaft 67 up to the pouring state when the sub open / close switching valve 63 is opened is S ₅ (S ₅ = S ₁ + S ₄ )
[0066]
That is, the switching order (switching timing) of the negative pressure release valve 64 and the auxiliary switching valve 63 accompanying the forward operation of the second valve shaft 67 is such that the negative pressure release valve 64 is closed first, and then The sub open / close switching valve 63 is set to open. Then, the spring 643 is contracted by the forward operation for the overstroke, and the valve body 641 of the negative pressure destruction valve 64 is firmly maintained in the closed state (see FIG. 3). On the other hand, when the second valve shaft 67 is reversely moved backward by this setting to return from the pouring state to the steady state, the sub open / close switching valve 63 is closed first. Next, the negative pressure release valve 64 is opened.
[0067]
Next, switching control will be described. In order to switch from the steady state to the pouring state, first, the electric motor 68 is energized to rotate the rotary operation shaft 681 counterclockwise by a predetermined amount. As a result, the second valve shaft 67 is first pushed by the second cam member 72 to move forward, and the negative pressure release valve 64 is first switched to the closed state, and then the sub open / close switching valve 63 is opened. Switched to the selected state. Next, the first valve shaft 66 is pushed by the first cam member 71 to move forward, and the main opening / closing switching valve 62 is switched to the opened state. As a result, the check valve 61 is opened by receiving the supply water pressure from the hot water supply circuit 2 side, and hot water can be poured from the hot water supply circuit 2 to the bathtub 3 side (see FIG. 3).
[0068]
On the other hand, when switching from the pouring state to the steady state, the electric motor 68 is first driven to rotate in the reverse direction, and the rotary operating shaft 681 is rotated in the clockwise direction by the same amount as described above. As a result, contrary to the above, the first valve shaft 66 starts to move backward in response to the compressive restoring force from the return spring 73 with the reverse rotation of the first cam member 71, and the main opening / closing switching valve 62 is The valve is switched to the closed state. Thereby, since pouring is interrupted, the check valve 61 is closed. Next, in response to the reverse rotation of the second cam member 72, the second valve shaft 67 starts to move backward upon receiving a compression restoring force from the return spring 74. By this reverse operation, first, the sub open / close switching valve 63 is first switched to the closed state, and then the negative pressure release valve 64 is switched to the opened state.
[0069]
When the main switching valve 62 is closed, the residual pressure enclosed in the pouring passage 50 between the main switching valve 62 and the check valve 61 acts on the main switching valve 62 as an operating resistance. Since the residual pressure of the same pressure acts in the opposite direction to the pressure cancel valve 65, the operation resistance is canceled and canceled, so that the first valve shaft 66 can be moved backward with a very light force. Become. That is, the first valve shaft 66 can close the main opening / closing switching valve 62 by the return spring 73 only by releasing the pressing force on the first valve shaft 66 by the reverse rotation of the first cam member 71. In addition, the spring load of the return spring 73 can be set to be relatively small. On the other hand, after the main opening / closing switching valve 62 is closed, the residual pressure remaining in the pouring passage 50 between 62 and 63 due to the closing of the sub opening / closing switching valve 63 passes through the negative pressure breaking valve 64 which is subsequently opened to the atmosphere. It is opened from the opening 645. This completes switching to the steady state.
[0070]
The switching control between the pouring state and the steady state by the drive control of the electric motor 68 is performed by pouring control by the controller 11. That is, in this pouring control, for example, when the hot water filling switch of the remote controller is turned ON, the above-described switching control to the pouring state is started, and the amount of hot water filling to the bathtub 3 based on the detected value from the pouring flow rate sensor 51 is started. When the water reaches a predetermined set water filling amount or the water level detection value from the water level sensor 47 reaches a predetermined set water level, pouring is completed and control for switching from the pouring state to the steady state is performed. Is called.
[0071]
According to the negative pressure breaking device 6 described above, even when the hot water supply circuit 2 side falls into a negative pressure state in the steady state after pouring, the negative pressure acts on the check valve 61 on the valve closing side. In addition, since the main on / off switching valve 62 and the sub on / off switching valve 63 are maintained in the closed state, the hot water supply circuit 2 side and the bathtub 3 side are maintained in the shut-off state. At this time, even if the check valve 61, the main on / off switching valve 62, and the sub on / off switching valve 63 are all closed due to foreign matter being caught, the negative pressure release valve 64 is forcibly opened. Therefore, air is immediately sucked in from the negative pressure destruction valve 64 and the atmosphere opening port 645, and the negative pressure is eliminated. As described above, the occurrence of reverse inflow from the bathtub 3 side to the hot water supply circuit 2 side can be prevented even if a negative pressure is generated in the hot water supply circuit 2 regardless of whether or not each valve is closed.
[0072]
In addition, since the occurrence of the above-mentioned negative pressure state may be caused by a power failure, a power failure occurs in order to reliably prevent the occurrence of reverse inflow caused by the above-mentioned abnormal closing operation even when a power failure occurs. A spare power source such as a backup power source (for example, an electrolytic capacitor) for supplying the electric power to the electric motor 68 for driving the second valve shaft 67 to return to the steady state at times may be mounted. Even in this case, the required electrostatic capacity of the standby power supply can be made extremely small to suppress a slight increase in cost.
[0073]
That is, as described above, the pressure canceling valve 65 cancels the resistance pressure when the main opening / closing switching valve 62 is closed, and the first cam member 71 is driven to rotate backward to release the pressing force on the first valve shaft 66. Since the first valve shaft 66 can be returned by the return spring 73 alone, reverse rotation of the electric motor 68 can be driven with a very low operating torque, and the required amount of rotation of the rotary operation shaft 681 of the electric motor 68 is also the first. Only a small amount is required such that the cam member 71 is reversely rotated by a predetermined amount. In addition, the main opening / closing switching valve 62 is closed first by the reverse rotation driving of the electric motor 68, and then the sub opening / closing switching valve 63 and the negative pressure release valve 66 are switched to the steady state. Similarly to the above, the valve shaft 67 is retracted by a very low operating torque and a small amount of rotation. For this reason, even if the reserve power source for supplying power to the electric motor 68 in the event of a power failure has an extremely small capacitance, not only the negative pressure destruction unit 64 but also the sub open / close switching valve 63 and the main open / close switching valve 62 are provided. It is possible to reliably switch back to the steady state.
[0074]
In order to mount the standby power supply as described above, the following may be performed. That is, for example, the controller 11 and the electric motor 68 are connected to each other by a control signal line and a power supply line, respectively, while the controller 11 is provided with a capacitor (electrolytic capacitor) having a relatively small capacitance as a reserve power source. In the normal state, the drive current to the electric motor 68 is supplied from the main power supply line, while in the event of a power failure, the electric motor 68 is rotated in a predetermined rotational direction by switching the switch due to the occurrence of the power failure (in the above case) What is necessary is just to comprise so that the drive current for reverse rotation drive and the later-mentioned "other aspect of 1st Embodiment; it is the case of the 1st case, it is normal rotation drive) may be supplied from the said capacitor | condenser.
[0075]
Furthermore, in the steady state after pouring, even if the hot water supply device 1 is installed downstairs and the bathtub 3 is installed at the upstairs position and the positive water head pressure in the piping acts on the hot water supply circuit 2 side, the positive water head Since the pressure acts on the side that presses the auxiliary opening / closing switching valve 63 toward the valve closing side, the pressure is not interrupted here and the backflow toward the hot water supply circuit 2 side does not occur. At this time, even if the sub-open / close switching valve 63 has an abnormal closing operation as described above, it is only overflowed from the opened negative pressure destruction valve 64 through the atmosphere opening port 645, and is supplied to the hot water supply circuit 2 side. Backflow is reliably prevented.
[0076]
Conversely, in a steady state after pouring, the hot water supply apparatus 1 is installed on the floor and the bathtub 3 is installed at the downstairs position, and negative water head pressure in the pipe acts on the sub open / close switching valve 63. However, if the spring load of the return spring 74 is set so as to overcome the expected negative water head pressure, the sub open / close switching valve 63 can be reliably maintained in the closed state. In this case, even if the return spring 74 is relatively strong, the opening / closing switching of the sub opening / closing switching valve 63 is performed by the driving force of the electric motor 68, so that the valve closing switching can be executed without any trouble.
[0077]
In addition, there is a diaphragm valve like the conventional negative pressure breaker 5 even if pulsation caused by a sudden opening / closing operation of the hot water taps 26a, 26b on the hot water supply circuit 2 side propagates from the hot water supply circuit 2 to the pouring channel 50, for example. Without water leakage due to the bounce of the diaphragm valve.
[0078]
(Other aspects of the first embodiment; Part 1)
When a standby power supply is installed as a countermeasure when a power failure occurs, as a measure for releasing the pressing force on the first and second valve shafts 66 and 67 in the pouring state and returning both valve shafts 66 and 67 to a steady state. As described above, the first and second cam members 71 and 72 are not driven by reverse rotation (clockwise rotation drive), but the two cam members 71 and 72 are further slightly rotated forward. You may make it carry out by.
[0079]
That is, when a power failure occurs in the pouring state, both the cam members 71 and 72 in the pouring state by the electric motor 68 that receives power supply from the standby power supply (cam members shown by the one-dot chain line and the two-dot chain line in FIG. 4). Is further forward rotated (counterclockwise rotational drive), the cam members 71 and 72 are disengaged from the valve shafts 66 and 67, so that the pressing force on the valve shafts 66 and 67 is released. Will be. As a result, the first valve shaft 66 is moved back by the return spring 73 and the second valve shaft 67 is moved back by the return spring 74, so that the valves 62, 63, 64 can be returned to the steady state. Become.
[0080]
In this case, since the required rotational amount of the electric motor 68 can be forward-rotated at a smaller angle than the case of reverse-rotation driving, the required capacitance required for the standby power source such as a capacitor can be further reduced. Thus, it is possible to further suppress the cost increase associated with the installation of the standby power supply. In this case, if the power failure is resolved, the controller 11 may be controlled to reset the positions of the cam members 71 and 72 to the initial positions.
[0081]
The above technical idea is expressed as subordinate to the negative pressure breaking device according to claim 2 or claim 8 of the claims. That is, the power supply unit includes a standby power supply unit for power failure, and the standby power unit releases the engagement of the cam member and the valve shaft in a steady state with respect to the drive unit in the event of a power failure so that the valve shaft is spring-returned. A negative pressure breaking device connected to the driving means so as to supply a driving power for further rotating forward and reverse one side.
[0082]
(Other aspects of the first embodiment; Part 2)
As the electric motor 68 as the driving means, a motor that can be stepped out when not energized (for example, a stepping motor) is adopted, and the spring load setting of the return springs 73 and 74 is increased by a predetermined amount unlike the above-described one, so Even if the installation of the standby power supply itself as a countermeasure is omitted, the valves 62, 63, 64 can be automatically returned to the steady state when a power failure occurs.
[0083]
That is, the spring load of the return spring 73 is added to the operating resistance of the first valve shaft 66 mainly due to the sliding resistance of the pressure cancel valve 65, and the rotation of the rotary operating shaft 681 when the stepping motor 68 is not energized. The resistance is set to be larger than the resistance against the return switching in consideration of the resistance. As a result, even when energization to the stepping motor 68 is stopped due to the occurrence of a power failure, the first valve shaft 66 is retracted only by the compression restoring force of the return spring 73 set with the spring load and automatically returned to the steady state. Will be able to.
[0084]
As a result, even when the hot water supply circuit 2 side falls into a negative pressure state when a power failure occurs, and both the main on / off switching valve 62 and the sub on / off switching valve 63 are abnormally closed, the negative pressure that has been automatically returned to the valve opening state is restored. By sucking air from the pressure breaking valve 64, the negative pressure is eliminated and the backflow from the bathtub 3 side can be reliably prevented. Such an effect can be obtained while avoiding all the cost increase due to the installation of the standby power supply.
[0085]
The above technical idea is expressed as subordinate to the negative pressure breaking device according to claim 2 or claim 8 of the claims. That is, the drive means is configured to be capable of step-out when not energized, and the return spring for returning the valve shaft to the spring is set to have a spring load larger than the position holding force of the drive means at the time of non-energization. Pressure breaking device.
[0086]
Second Embodiment
5 and 6 show the negative pressure breaking device 8 of the second embodiment, FIG. 5 shows a steady state, and FIG. 6 shows a pouring state. The negative pressure breaking device 8 according to the second embodiment is obtained by further adding a pouring electromagnetic valve 69 having a pilot diaphragm valve to the negative pressure breaking device 6 according to the first embodiment. Therefore, the addition of the pouring electromagnetic valve 69 may of course be applied to another aspect of the first embodiment: Part 1 or Part 2. The other components of the added hot water solenoid valve 69 are the same as those of the negative pressure breaking device 6 of the first embodiment. Hereinafter, the same components as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and detailed description thereof will be omitted. Hereinafter, different components will be mainly described.
[0087]
The pouring electromagnetic valve 69 is constituted by a normally closed electromagnetic control valve, and includes a pilot diaphragm valve 691. That is, a cylindrical valve seat 692 having a valve seat portion around the tip thereof is disposed on one side of the flexible diaphragm valve 691, while a diaphragm chamber 693 is defined on the other side. And the inside of the said cylindrical valve seat 692 is connected to the downstream (tub 3 side), and the donut annular space 694 of the outer peripheral side is connected to the upstream (hot water supply circuit 2 side). The diaphragm valve 691 is opened and closed with respect to the distal end by elastic deformation so that the hot water supply circuit 2 side and the bathtub 3 side are connected or disconnected. The diaphragm chamber 693 is bleed-in with upstream pressure (water supply pressure on the hot water supply circuit 2 side) through the bleed hole 691a, and the diaphragm valve 691 is maintained in a closed state by this water supply pressure.
[0088]
On the other hand, the diaphragm valve 691 is penetrated by a center hole 695 communicating with the inside of the cylindrical valve seat 692, and the center hole 695 is closed by the plunger 696 when not energized (in a steady state), while being energized (note) During hot water), the plunger 696 is retracted against the spring 698 by the electromagnet 697 to communicate with the diaphragm chamber 693, thereby converting the diaphragm valve 691 into the valve open state. In other words, the plunger 696 is pushed by the spring 698 to close the center hole 695 when not energized, thereby keeping the diaphragm valve 691 closed by the water supply pressure, while the plunger 696 is electromagnet 697 when energized. The normally closed type is configured to open the diaphragm valve 691 by being driven backward.
[0089]
The switching control in the case of the second embodiment will be described. In order to switch from the steady state to the pouring state, the electric motor 68 is driven to rotate forward (counterclockwise rotation drive) as in the case of the first embodiment, First, the negative pressure release valve 64 is closed by the forward operation of the second valve shaft 67 and then the sub-open / close switching valve 63 is opened, and then the main open / close switching valve 62 is operated by the forward operation of the first valve shaft 66. Open the valve. And finally, the molten metal electromagnetic valve 69 is energized to open the diaphragm valve 691. As a result, the check valve 61 is opened by receiving the feed water pressure from the hot water supply circuit 2 side, and hot water can be poured from the hot water supply circuit 2 to the bathtub 3 side (see FIG. 6).
[0090]
On the other hand, when switching from the pouring state to the steady state, the energization of the pouring electromagnetic valve 69 is first stopped to return the diaphragm valve 691 to the closed state. Thereby, since pouring is interrupted, the check valve 61 is closed. Next, by reversely driving the electric motor 68 (clockwise rotation drive), the main on / off switching valve 62 is closed, the sub on / off switching valve 63 is closed, and the negative pressure breaking valve 64 is turned on. Open the valve.
[0091]
Note that the above-described drive control of the electric motor 68 and the switching control between the pouring state and the steady state by the energization control to the pouring electromagnetic valve 69 are the pouring control by the controller 11 as described in the first embodiment. Is to be done by.
[0092]
According to the second embodiment described above, the auxiliary on-off switching valve 63 and the negative pressure release valve 64 coupled to the second valve shaft 67, and the main on-off switching valve 62 and the pressure coupled to the first valve shaft 66. Since a pouring electromagnetic valve 69 is additionally provided in the pouring passage 50 located upstream of the cancel valve 65, the reliability with respect to mutual switching between the pouring state and the steady state is further increased as compared with the first embodiment. Will be able to. When switching from the steady state to the pouring state, the pouring solenoid valve 69 is closed until the on / off switching valves of the downstream main switching valve 62, the negative pressure release valve 64, and the auxiliary switching valve 63 are completed. On the other hand, when switching from the pouring state to the steady state, the pouring electromagnetic valve 69 is first switched to the closed state, so that the first valve shaft 66 and the second valve shaft 67 are switched. The first and second cam members 71 and 72 may be simplified by making the first cam member 71 and the second cam member 72 have the same shape and arrangement as in the first embodiment.
[0093]
The technical idea of the second embodiment described above is expressed as follows. Here, the above-described hot water solenoid valve 69 is grasped as a main on / off switching valve, the main on / off switching valve 62 as a first sub on / off switching valve, and the sub on / off switching valve 63 as a second sub on / off switching valve.
[0094]
A water-reserved storage tank is connected to a purified water supply path to which purified water is supplied under a predetermined water supply pressure through a branch path branched from the purified water supply path so that water can be injected, and the purified water supply path is interposed in the branch path. In the negative pressure breaker that breaks the negative pressure while allowing water injection to switch between the tank and the storage tank,
In order from the upstream side with respect to the branch path, a drive type main on / off switching valve that switches between opening and closing of water injection or shutoff, and a first and second pair of driven sub on / off switching valves are provided, respectively. The first sub-open / close switch valve is provided with a pressure cancel valve that cancels out the internal pressure from the purified water supply path acting on the upstream side of the first sub-open / close switch valve. A drive-type negative pressure destruction valve that communicates with the position between the two secondary on / off switching valves and performs on / off switching of communication with or shutting off from the atmosphere side is provided;
The first sub opening / closing switching valve and the pressure canceling valve are respectively coupled to a first valve shaft that receives the driving force in the advancing / retreating direction to switch the first sub opening / closing switching valve, and the second sub opening / closing switching valve. The valve and the negative pressure release valve are respectively coupled to the second valve shaft that receives the driving force in the advancing / retreating direction and performs the open / close switching of both the second sub open / close switching valve and the negative pressure release valve,
The second valve shaft receives the advance / retreat driving force from the drive means and operates to one side in the advance / retreat direction, thereby switching the second sub-open / close switch valve from the closed state to the open state and the negative pressure breaking valve. Is switched from the open state to the closed state to switch the second sub-open / close switching valve and the negative pressure release valve from the steady state to the water injection state, while operating from the other side in the forward / backward direction to change the water injection state to the steady state. A negative pressure breaker configured to return after switching.
[0095]
<Other embodiments>
In addition, this invention is not limited to the structure described in the said 1st or 2nd embodiment and these other aspects, It includes other various embodiment. That is, in the first or second embodiment, the case has been described in which the first valve shaft 66 and the second valve shaft 67 are advanced and retracted by the electric motor 68 as a common drive means. The first valve shaft 66 and the second valve shaft 67 may be advanced and retracted by individual driving means. In this case, as individual drive means, each valve shaft may be individually cam-driven by a combination of an electric motor and a cam member as in the first or second embodiment, or each valve You may make it employ | adopt a cylinder etc. which move a axis | shaft linearly in an advance / retreat direction, or an electromagnetic drive means. For example, FIG. 7 shows a case where electromagnetic drive means 91 and 92 are employed as individual drive means for the valve shafts 66 and 67 by taking the second embodiment as an example.
[0096]
Moreover, in the said embodiment, the case where the negative pressure destruction devices 6, 8, and 9 are applied to the hot water supply device which performs pouring from the hot water supply circuit 2 to the bathtub 3 through the recirculation circuit 4 as an example. However, the present invention is not limited to this, and the present invention is not limited to the hot water supply apparatus in which the recirculation circuit 4 is omitted, that is, the bath portion is omitted and the hot water supply circuit 2 directly pours water into the bathtub 3. A pressure breaking device may be applied. In this case, the “pouring” is hot water of a predetermined temperature.
[0097]
In the above embodiment, the case where the negative pressure breaking device 6 is applied is described by taking the hot water supply device when the hot water supply destination from the hot water supply circuit 2 is the bathtub 3 as an example, but not limited thereto, the hot water supply circuit 2 or the water injection The negative pressure breaking device of the present invention may be applied to a hot water supply device in which the hot water / water supply destination from the circuit is used as a washing tub. In this case as well, the same effect can be obtained. In this case, the hot water supply path 50 or the downstream end of the water injection path, which is a branch path from the hot water supply circuit 2 or the water injection circuit, is connected to the bottom of the washing tub, and hot water or water for washing is poured into the washing tub.・ It should be possible to inject water. Since the washing tub is a storage tub open to the atmosphere and the hot water or water used here is miscellaneous water, it is necessary to prevent the occurrence of backflow as in the case of the bathtub.
[0098]
Furthermore, the negative pressure breaking device of the present invention can be applied to devices other than the hot water supply device described in the above embodiment. For example, a branch branched from a water supply pipe or from a pipe (for example, a purified water supply line such as a water supply circuit that receives purified water and supplies water to a faucet) from a water receiving tank by pumping water pressure. When the pipe is connected to the bottom of a storage tank open to the atmosphere (for example, the above-described bathtub or washing tub) and water can be injected by switching the opening / closing valve for water injection, the negative pressure breaking device 6 of the above embodiment is connected to the branch pipe. , 8, 9 may be interposed. Also in this case, it is possible to reliably prevent the backflow from the storage tank to the purified water supply path due to the abnormal valve closing operation or the occurrence of a power failure as in the above embodiment.
[0099]
In the first or second embodiment, the valve shafts 66 and 67 are divided into the pins 66a and 67a and the shaft bodies 66b and 67b mainly for the convenience of assembly work. You may form by an integral thing.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a hot water supply apparatus to which an embodiment of the present invention is applied.
FIG. 2 is an explanatory cross-sectional view showing a steady state of the negative pressure breaker according to the first embodiment.
FIG. 3 is a view corresponding to FIG. 2 showing a pouring state of the negative pressure breaking device according to the first embodiment.
FIG. 4 is an enlarged explanatory view of a cam member portion of the first embodiment.
FIG. 5 is an explanatory cross-sectional view showing a steady state of the negative pressure breaker according to the second embodiment.
FIG. 6 is a view corresponding to FIG. 5 showing a pouring state of the negative pressure breaking device of the second embodiment.
FIG. 7 is a view corresponding to FIG. 5 showing another embodiment.
FIG. 8 is a view corresponding to FIG. 1 showing a hot water supply apparatus to which a conventional negative pressure breaking device is applied.
[Explanation of symbols]
2 Hot water supply circuit (purified water supply path)
3 Bathtub (storage tank)
6,8,9 Negative pressure breaker
26a, 26b Hot water tap (water tap)
50 Pouring path (branch path)
62 Main switching valve
63 Sub open / close switching valve
64 Negative pressure release valve
65 Pressure cancel valve
66 First valve stem (valve stem)
67 Second valve stem
68 Electric motor (drive means)
71 First cam member
72 Second cam member
73, 74 Return spring
91, 92 Electromagnetic driving means (driving means)
681 Rotating shaft

Claims

A water-reserved storage tank is connected to a purified water supply path to which purified water is supplied under a predetermined water supply pressure through a branch path branched from the purified water supply path so that water can be injected, and the purified water supply path is interposed in the branch path. In the negative pressure breaker that breaks the negative pressure while allowing water injection to switch between the tank and the storage tank,
A main on / off switching valve intervening in the branch path and performing on / off switching of water injection or shutoff;
A pressure canceling valve that cancels out the internal pressure from the purified water supply passage acting on the upstream side of the main switching valve;
A drive-type sub on / off switching valve that is interposed at the downstream side position of the main on / off switching valve and performs switching on / off of water injection or shutoff;
A drive-type negative pressure release valve that is arranged in communication with the position between the sub-open / close switch valve and the main open / close switch valve and performs open / close switching of communication with or shutting off from the atmosphere side;
A negative pressure breaking device comprising: a valve shaft for connecting the main opening / closing switching valve and the pressure canceling valve to each other and receiving an advance / retreat driving force to switch the main opening / closing switching valve.

The negative pressure breaking device according to claim 1,
A driving means for applying an advancing / retreating driving force to the valve shaft;
The driving means transmits a rotational driving force to a rotational operation shaft and rotationally operates a cam member coupled to the rotational operation shaft.
The valve shaft is disposed so as to be orthogonal to the rotational operation shaft, and the main open / close switching valve is closed by receiving a pressing force from one end to one side in the forward / backward direction by the forward / reverse one side rotation of the cam member. It is configured to switch from the steady state to the water injection state in which the valve is opened, while the pressing force is released by the forward and reverse rotation of the cam member and the spring is returned to the steady state from the water injection state by the spring. The negative pressure breaker.

A water-reserved storage tank is connected to a purified water supply path to which purified water is supplied under a predetermined water supply pressure through a branch path branched from the purified water supply path so that water can be injected, and the purified water supply path is interposed in the branch path. In the negative pressure breaker that breaks the negative pressure while allowing water injection to switch between the tank and the storage tank,
A main on / off switching valve interposed in the branch path for switching on / off of water injection or shutoff, a pressure canceling valve for offsetting the internal pressure from the purified water supply path acting on the upstream side of the main on / off switching valve, and the main A sub-opening / closing switching valve that is interposed at a downstream position of the opening / closing switching valve and performs on / off switching of water injection or shutoff, and is disposed in communication with a position between the sub-opening / closing switching valve and the main switching valve. The negative pressure release valve that switches between opening and closing the communication with the atmosphere side, and the main switching valve and the pressure canceling valve are coupled to each other to receive the driving force in the forward / backward direction and switch the opening and closing of the main switching valve. A first valve shaft to be operated, and the sub-open / close switching valve and the negative pressure release valve are coupled to each other and receive the driving force in the forward / backward direction to perform opening / closing switching of both the sub-open / close switching valve and the negative pressure release valve The second valve shaft is a drive shaft. In response to the forward / backward driving force from the means, the auxiliary open / close switching valve is opened from the closed state and the negative pressure release valve is switched from the opened state to the closed state by operating in the forward / backward direction. The sub-opening / closing switching valve and the negative pressure release valve are switched from the steady state to the water injection state, while operating in the forward / backward direction to the other side to switch from the water injection state to the steady state and return. Characteristic negative pressure breaker.

The negative pressure breaking device according to claim 3,
Driving means for applying a driving force to one side in the forward / backward direction with respect to the second valve shaft;
A return spring for applying a return force to the other side of the second valve shaft in the forward / backward direction, and the second valve shaft is driven to one side in the forward / backward direction upon receiving a driving force from the driving means. As a result, the sub open / close switching valve and the negative pressure release valve are switched from the steady state to the water injection state. On the other hand, when the maintenance force of the water injection state by the driving means is released, the sub open / close valve receives the return force from the return spring. A negative pressure breaking device configured such that the switching valve and the negative pressure breaking valve are switched from the water injection state to the steady state and returned.

The negative pressure breaking device according to claim 3 or 4,
When switching from the steady state to the water injection state by driving the second valve shaft toward one side in the forward / backward direction, the sub open / close switching valve closes the negative pressure release valve from the open state to the second valve shaft. A negative pressure breaking device associated with the second valve shaft so as to start the valve opening operation from the closed state by receiving an operating force from the second valve shaft after a stroke for switching to the valve state. .

The negative pressure breaking device according to any one of claims 3 to 5,
The timing at which the driving force is applied to one side in the forward / backward direction with respect to the first valve shaft and the second valve shaft is such that the driving force is first applied to the second valve shaft so that the negative pressure breaking valve and the sub open / close switching valve Is switched from the steady state to the water injection state, and after this is completed, a driving force is applied to the first valve shaft to switch the main open / close switching valve from the steady state in the closed state to the water injection state in the open state. A negative pressure breaker that is set to do.

The negative pressure breaking device according to claim 6,
A common driving means for applying a driving force to each of the first valve shaft and the second valve shaft;
The drive means is disposed so as to be orthogonal to the first and second valve shafts, and receives a rotational drive force from the drive means. The drive means swings by the rotational drive of the rotary action shaft. A negative pressure breaking device comprising: a first and a second pair of cam members that are rotated to transmit operating force in the forward and backward directions to the first and second valve shafts.

The negative pressure breaking device according to any one of claims 1 to 7,
A spring that urges the valve body of the sub-open / close switching valve to the valve closing side is closed, this spring overcomes the negative head pressure from the downstream side that sucks the valve body of the sub-open / close switching valve to the valve opening side. A negative pressure breaking device that is set to have a spring load that can be maintained at a low pressure.

The negative pressure breaking device according to any one of claims 1 to 8,
The purified water supply path is a hot water supply circuit that receives purified water and is heated by a heating source to supply hot water to the hot water tap side or a water supply circuit that receives purified water and supplies water to the water tap side, and the hot water supply circuit or water supply circuit On the other hand, a negative pressure breaker in which a storage tank open to the atmosphere is connected to allow for pouring or pouring water through a branch passage.