JP3569624B2

JP3569624B2 - Manual reset device for emergency valve for water tank

Info

Publication number: JP3569624B2
Application number: JP05680598A
Authority: JP
Inventors: 稔長尾
Original assignee: Kubota Corp
Current assignee: Kubota Corp
Priority date: 1998-03-09
Filing date: 1998-03-09
Publication date: 2004-09-22
Anticipated expiration: 2018-03-09
Also published as: JPH11257508A

Description

【０００１】
【発明の属する技術分野】
本発明は、水道施設の配水本管と耐震貯水槽の間の管路に介設して、配水本管の破損等の異常事態発生時に緊急に作動させ、貯水槽への汚水の流入を防止するとともに、配水本管の通水を確保する貯水槽用緊急弁の手動復帰装置に関する。
【０００２】
【従来の技術】
従来より、たとえば図１２に示すような水道施設における配水本管１の上流側本管１Ａと耐震貯水槽２（以下、単に貯水槽２という）の入口２Ａとを連通させる流入管３に介設した流入弁４と、貯水槽２の出口２Ｂと配水本管１の下流側本管１Ｂとを連通させる流出管５に介設した流出弁６および流入管３における流入弁４の上流位置と流出管５における流出弁６の下流位置、つまり流入管３の一次側３Ａと流出管５の二次側５Ｂとを連通させるバイパス管７に介設したバイパス弁８の３個の弁４、６、８を使用した貯水槽用緊急弁が知られている。なお、図中Ｖ１、Ｖ２、Ｖ３は制水弁を示す。
【０００３】
前記構成の貯水槽用緊急弁において、平常時には、図１２のようにバイパス弁８と制水弁Ｖ１が弁閉され、流入弁４と流出弁６および制水弁Ｖ２、Ｖ３が弁開される。このため、水は矢印で示すように、配水本管１の上流側本管１Ａ→流入管３の一次側３Ａ→流入弁４→流入管３の二次側３Ｂの経路で貯水槽２に流入して貯水される。また、貯水槽２から出た水は、流出管５の一次側５Ａ→流出弁６→流出管５の二次側５Ｂ→配水本管１の下流側本管１Ｂの経路で流下する。この状態で貯水槽２は水道管路の一部として機能する。
【０００４】
たとえば、地震などにより配水本管１に破損等の異常事態が発生して、配水本管１の水圧が設定値以下に低下すると、この水圧を検知して、図１３に示すように、流入弁４と流出弁６が弁閉され、バイパス弁８が弁開する。このため、水は矢印で示すように、配水本管１の上流側本管１Ａ→流入管３の一次側３Ａ→バイパス管７→流出管５の二次側５Ｂ→配水本管１の下流側本管１Ｂの経路で流下する。これにより、貯水槽２への汚水の流入を防止して、応急給水用の飲料水を貯水槽２内に確保するとともに、配水本管１の通水確保により配水本管１に接続されている消火栓（図示省略）などの使用可能な状態を得ることができる。
【０００５】
しかし、前記この種の貯水槽用緊急弁は、流入弁４と流出弁６およびバイパス弁８の３つの弁を必要とし弁の使用台数が多くなり、それだけ誤動作が生じる確率も高くなる。このため、異常事態の発生時に、前記３つの弁の少なくとも１つの弁に誤動作が生じると、貯水槽２への汚水の流入を防止できても配水本管１の通水が確保されない不都合、あるいは配水本管１の通水を確保できても、貯水槽２への汚水の流入を防止できない不都合などが発生する。しかも、大きい設置スペースが必要になる。
【０００６】
そこで、弁の使用台数を減らし、弁の誤動作が生じる確率を低くすることで、前述の欠点を解消した貯水槽用緊急弁が提供されている。この種の貯水槽用緊急弁は、図１４および図１５に示すように、１台の緊急遮断式のバタフライ弁９を備えている。バタフライ弁９は、配水本管側の分流管１０Ａと、貯水槽側の分流管１０Ｂとの間に介設される。配水本管側の分流管１０ＡはＴ字管１１を介して流入管３の一次側３Ａと流出管５の二次側５Ｂに接続され、貯水槽側の分流管１０ＢはＴ字管１２を介して流入管３の二次側３Ｂと流出管５の一次側５Ａに接続される。また、配水本管側の分流管１０Ａは、上側の通路５Ｂ１と下側の通路３Ａ１に区画されており、貯水槽側の分流管１０Ｂは、上側の通路５Ａ１と下側の通路３Ｂ１に区画されている。そして、Ｔ字管１１には、流入管３の一次側３Ａと配水本管側の分流管１０Ａにおける下側の通路３Ａ１とを連通させ、かつ流出管５の二次側５Ｂと配水本管側の分流管１０Ａにおける上側の通路５Ｂ１とを連通させる隔壁１１Ａが設けられ、Ｔ字管１２には、流入管３の二次側３Ｂと貯水槽側の分流管１０Ｂにおける下側の通路３Ｂ１とを連通させ、かつ流出管５の一次側５Ａと配水本管側の分流管１０Ｂにおける上側の通路５Ａ１とを連通させる隔壁１１Ａが設けられている。なお、図中Ｖ１は制水弁を示す。
【０００７】
このような構成であれば、平常時には、図１４および図１５のようにバタフライ弁９が弁開され、制水弁Ｖ１が弁閉される。このため、水は矢印で示すように、配水本管１の上流側本管１Ａ→流入管３の一次側３Ａ→Ｔ字管１１Ａ→配水本管側の分流管１０Ａの下側の通路３Ａ１→バタフライ弁９→貯水槽側の分流管１０Ｂの下側の通路３Ｂ１→流入管３の二次側３Ｂの経路で貯水槽２に流入して貯水される。また、貯水槽２から出た水は、流出管５の一次側５Ａ→Ｔ字管１２Ａ→貯水槽側の分流管１０Ｂの上側の通路５Ａ１→バタフライ弁９→配水本管側の分流管１０Ａの上側の通路５Ｂ１→Ｔ字管１１Ａ→流出管５の二次側５Ｂ→配水本管１の下流側本管１Ｂの経路で流下する。この状態で貯水槽２は水道管路の一部として機能する。
【０００８】
たとえば、地震などにより配水本管１に破損等の異常事態が発生して、配水本管１の水圧が設定値以下に低下すると、この水圧を検知して、図１６および図１７に示すようにバタフライ弁９が弁閉する。このため、水は矢印で示すように、配水本管１の上流側本管１Ａ→流入管３の一次側３Ａ→Ｔ字管１１Ａ→配水本管側の分流管１０Ａの下側の通路３Ａ１→バタフライ弁９の手前→配水本管側の分流管１０Ａの上側の通路５Ｂ１→Ｔ字管１１Ａ→流出管５の二次側５Ｂ→配水本管１の下流側本管１Ｂの経路で流下する。これにより、貯水槽２への汚水の流入を防止して、応急給水用の飲料水を貯水槽２内に確保するとともに、配水本管１の通水確保により配水本管１に接続されている消火栓（図示省略）などの使用可能な状態を得ることができる。
【０００９】
しかし、弁の使用台数を減らすように工夫された上記の貯水槽用緊急弁は、上側の通路５Ｂ１と下側の通路３Ａ１に区画した配水本管側の分流管１０Ａと、上側の通路５Ａ１と下側の通路３Ｂ１に区画した貯水槽側の分流管１０Ｂと、流入管３の一次側３Ａと配水本管側の分流管１０Ａにおける下側の通路３Ａ１とを連通させ、かつ流出管５の二次側５Ｂと配水本管側の分流管１０Ａにおける上側の通路５Ｂ１とを連通させる隔壁１１Ａが設けられたＴ字管１１および流入管３の二次側３Ｂと貯水槽側の分流管１０Ｂにおける下側の通路３Ｂ１とを連通させ、かつ流出管５の一次側５Ａと貯水槽側の分流管１０Ｂにおける上側の通路５Ａ１とを連通させる隔壁１２Ａが設けられたＴ字管１２を必要とする。しかも、これら配水本管側の分流管１０Ａ、貯水槽側の分流管１０Ｂ、Ｔ字管１１およびＴ字管１２は、それぞれ構造が複雑であるから製作に困難を伴う。
【００１０】
そこで、本発明出願人は、特願平９−１４６４９６号において、弁の使用台数を減らし、異常事態の発生時に前述の不都合が発生する確率を低下させることで信頼性を高めるとともに、設置スペースを縮小し、かつ構造が複雑な分流管やＴ字管などの配管材料の使用を省略して、簡単に製作することができる貯水槽用緊急弁を既に提供している。
【００１１】
この種の貯水槽用緊急弁は、図１および図２に示すように、１つの筒状の弁箱１３と、この弁箱１３の内部に軸方向の移動自在に装入された弁本体１４とを備えている。弁本体１４は弁棒部１４Ｄと、この弁棒部１４Ｄの軸方向一端部に取付けられたピストン部１４Ａと、弁棒部１４Ｄの軸方向の他端側に偏って取付けられた第１弁体部１４Ｂおよびピストン部１４Ｆと、弁棒部１４Ｄの軸方向の略中央部に取付けられた第２弁体部１４Ｃを有し、ピストン部１４Ａ、第１弁体部１４Ｂ、第２弁体部１４Ｃ、ピストン部１４Ａおよびピストン部１４Ｆの外周面と弁箱１３の内周面とで水封できるように構成されている。
【００１２】
弁箱１３の内部には、環状の第１弁箱シート１３Ａ、環状の第２弁箱シート１３Ｂおよび環状の第３弁箱シート１３Ｃが設けられ、ピストン部１４Ａは環状の第１弁箱シート１３Ａの軸方向一端側の圧力室１６内に位置し、ピストン部１４Ｆは軸方向他端側の付勢室１７内に位置しており、第１弁体部１４Ｂは付勢室１７の近くに位置している。また、第２弁体部１４Ｃは環状の第１弁箱シート１３Ａと環状の第２弁箱シート１３Ｂの間の流入室１８内に位置しており、環状の第２弁箱シート１３Ｂと環状の第３弁箱シート１３Ｃの間に流出室１９が形成されている。
【００１３】
一方、弁箱１３には、その周壁を貫通して流入室１８に通じる第１流入ポートＰ１と、流出室１９に通じる第１流出ポートＰ２が形成されているとともに、これら各ポートＰ１，Ｐ２の形成位置から周方向に１８０゜離れた位置の周壁を貫通して、第１弁箱シート１３Ａを介して流入室１８に通じる第２流出ポートＰ３と、第３弁箱シート１３Ｃを介して流出室１９に通じる第２流入ポートＰ４が形成されている。また、前記弁箱１３の一端部を貫通して圧力室１６に通じるパイロットポートＰ５が形成され、前記付勢室１７内にはスプリングによってなる付勢手段１５が装入されており、弁本体１４を軸方向一端側に向けて常時付勢している。
【００１４】
貯水槽用緊急弁Ｖは、水道施設における配水本管１と貯水槽２の間に介設される。すなわち、配水本管１の上流側本管１Ａは流入管３の一次側３Ａを介して第１流入ポートＰ１に接続され、配水本管１の下流側本管１Ｂは流出管５の二次側５Ｂを介して第１流出ポートＰ２に接続されるとともに、貯水槽２の入口２Ａは流入管３の二次側３Ｂを介して第２流出ポートＰ３に接続され、貯水槽２の出口２Ｂは流出管５の一次側５Ａを介して第２流入ポートＰ４に接続されている。また、配水本管１の上流側本管１Ａは導水管管２０を介してパイロットポートＰ５に接続されている。図中Ｖ１は制水弁を示す。
【００１５】
他方、付勢室１７の外側には、軸方向他端側に延びる弁本体の開度指示装置３０が設けられている。この弁本体の開度指示装置３０は、付勢室１７の外端壁部１７Ａに貫設した弁棒挿通孔１７ａを介して、付勢室１７の内部に連通して該付勢室１７の外側に軸方向他端側に延びて取付けられた筒状の弁棒カバー３０Ａと、弁棒挿通孔１７ａを貫通して弁棒カバー３０Ａの内部に挿入された弁棒部１４Ｄの弁箱外突出部１４ｄと、この弁箱外突出部１４ｄに固着された扇型もしくは円盤状の弁開度指示部材３０Ｂ（ただし、本実施の形態では扇型の弁開度指示部材３０Ｂを固着している）と、弁開度指示部材３０Ｂの外周部に対応し、かつ前記軸方向に延びて弁棒カバー３０Ａの周壁部に貫設された弁開度指示部材の目視用窓部３０Ｃとを具備しており、弁開度指示部材の目視用窓部３０Ｃ近くの弁棒カバー３０Ａの周壁部には、目視用窓部３０Ｃの軸方向の他端側（一方側）に偏って文字「開」が表示され、目視用窓部３０Ｃの軸方向の一端側（他方側）に偏って文字「閉」が表示されている。
【００１６】
さらに、この種の貯水槽用緊急弁Ｖは自動復帰装置４０を備えている。自動復帰装置４０は、導水管２０に介設されるとともに、導水管２０の水圧をダイヤフラム室に取り込んで前記平常時には図１のように弁開され、かつ前記異常事態発生時には図２のように弁閉されるダイヤフラム弁によってなる制水弁４１と、この制水弁４１の下流側で導水管２０から分岐された排水管４２と、この排水管４２に介設されるとともに、導水管２０における制水弁４１よりも上流側の水圧をダイヤフラム室に取り込んで前記平常時には図１のように弁閉され、かつ前記異常事態発生時には図２のように弁開されるダイヤフラム弁によってなる排水弁４３とによって構成されている。
【００１７】
前記構成において、平常時における配水本管１および導水管２０の水圧は設定値を超えている。制水弁４１のダイヤフラム室には導水管２０から設定値を超えている高い水圧が取り込まれるので弁開し、排水弁４３のダイヤフラム室にも導水管２０から設定値を超えている高い水圧が取り込まれるので弁閉する。このため、設定値を超えている高い水圧をパイロット圧として導水管２０→パイロットポートＰ５の経路で圧力室１６に導入し、弁本体１４のピストン部１４Ａに負荷することができる。弁本体１４のピストン部１４Ａに高いパイロット圧が負荷されると、付勢手段１５の付勢に抗して弁本体１４を弁箱１３の軸方向他端側に移動させて、貯水槽用緊急弁Ｖを弁開する。これにより、流入室１８を介して、第１流入ポートＰ１と第２流出ポートＰ３が連通するとともに、流出室１９を介して、第１流出ポートＰ２と第２流入ポートＰ４が連通する。このため、水は矢印で示すように、配水本管１の上流側本管１Ａ→流入管３の一次側３Ａ→第１流入ポートＰ１→流入室１８→→第２流出ポートＰ３→流入管３の二次側３Ｂの経路で貯水槽２に流入して貯水される。また、貯水槽２から出た水は、流出管５の一次側５Ａ→第２流入ポートＰ４→流出室１９→第１流出ポートＰ２→流出管５の二次側５Ｂ→配水本管１の下流側本管１Ｂの経路で流下する。この状態で貯水槽２は水道管路の一部として機能する。
【００１８】
この場合、弁棒部１４Ｄの弁箱外突出部１４ｄに固着されている弁開度指示部材３０Ｂは、筒状の弁棒カバー３０Ａの軸方向の一方側に偏った全開指示位置、つまり表示文字「開」に対応する位置に在り、この全開指示位置に在る弁開度指示部材３０Ｂを目視用窓部３０Ｃから視認することによって、弁本体１４の全開状態を確認することができる。
【００１９】
たとえば、地震などにより配水本管１に破損等の異常事態が発生して、配水本管１の水圧が設定値以下に低下すると、制水弁４１のダイヤフラム室には導水管２０から設定値以下の低い水圧が取り込まれるので弁閉し、排水弁４３のダイヤフラム室にも導水管２０から設定値以下の低い水圧が取り込まれるので弁開する。このため、圧力室１６は導水管２０の一部と排水管４２を介して大気開放される。その結果、図２に示すように、付勢手段１５の付勢により第２弁体部１４Ｃが第１弁箱シート１３Ａに当接し、かつ第１弁体部１４Ｂが第３弁箱シート１３Ｃに当接する位置まで、弁本体１４を弁箱１３の軸方向一端側に移動させる。これにより、流入室１８と流出室１９を介して、第１流入ポートＰ１と第１流出ポートＰ２が連通する。このため、水は矢印で示すように、配水本管１の上流側本管１Ａ→流入管３の一次側３Ａ→第１流入ポートＰ１→流入室１８→流出室１９→第１流出ポートＰ２→流出管５の二次側５Ｂ→配水本管１の下流側本管１Ｂの経路で流下する。したがって、貯水槽２への汚水の流入を防止して、応急給水用の飲料水を貯水槽２内に確保するとともに、配水本管１の通水確保により配水本管１に接続されている消火栓（図示省略）などの使用可能な状態を得ることができる。
【００２０】
ところが、前述の自動復帰装置４０では、異常事態の発生後に配水本管１の破損箇所等が補修されることで、配水本管１の水圧が設定値を超える値に回復するのと同時に自動復帰して、貯水槽用緊急弁Ｖを図１に示す平常状態に復帰させることになる。このため、配水本管１の補修時に管内に取り込まれた土砂などを含む泥水が貯水槽２に流入して、貯水槽２内の水を応急給水用の飲料水として供給し得なくなる事態が生じるおそれを有している。
【００２１】
【発明が解決しようとする課題】
すなわち、従来の貯水槽用緊急弁の欠点を解消した貯水槽用緊急弁の自動復帰装置では、配水本管の破損箇所の補修完了後に配水本管の水圧が回復するのと同時自動復帰して弁本体を弁開し、貯水槽を配水管路の一部として機能させることになるので、配水本管における貯水槽用緊急弁の設置位置よりも上流側で破損等の異常事態が発生すると、破損箇所の補修時に配水本管に取り込まれた異物によって汚れた水が誤って貯水槽に入り込み、貯水槽内の水を応急給水用の飲料水として供給し得なくなる事態が生じるおそれを有している。
【００２２】
そこで、本発明は、従来の貯水槽用緊急弁の欠点を解消した貯水槽用緊急弁において、たとえ配水本管における貯水槽用緊急弁の設置位置よりも上流側で破損等の異常事態が発生し、破損箇所の補修時に管内に異物が取り込まれても、この異物によって汚れた水が誤って貯水槽に入り込むのを確実に防止できる貯水槽用緊急弁の手動復帰装置を提供することを目的としたものである。
【００２３】
【課題を解決するための手段】
前記目的を達成するために、本発明に係る貯水槽用緊急弁の手動復帰装置は、筒状の弁箱の周壁部に配水本管の上流側本管に通じる第１流入ポートと、配水本管の下流側本管に通じる第１流出ポートと、貯水槽の入口に通じる第２流出ポートと、貯水槽の出口に通じる第２流入ポートが設けられ、前記弁箱の内部に軸方向の移動自在に弁棒部を備えた弁本体が装入され、この弁本体を常時軸方向の一方側に付勢する第１付勢手段と、この第１付勢手段の付勢に抗して弁本体を軸方向の他方側に付勢する圧力室および該圧力室と前記配水本管側とを連通させる導水管とを備え、前記配水本管側の水圧が作動設定値を超えている平常時には、前記圧力室の水圧により前記第１付勢手段の付勢に抗して前記弁本体を前記弁箱の軸方向の一方側に移動させて、前記第１流入ポートと第２流出ポートおよび第１流出ポートと第２流入ポートを連通させた弁開状態で、前記貯水槽を配水管路の一部として機能させるとともに、前記配水本管側の水圧が作動設定値以下に低下した異常事態発生時には、前記第１付勢手段の付勢により前記圧力室の水圧に抗して前記弁本体を前記弁箱の軸方向の他方側に移動させて、前記第１流入ポートと第１流出ポートを連通させた弁閉状態で、前記貯水槽への汚水の流入を防止して、該貯水槽内に飲料水を確保し、かつ前記配水本管の通水を確保するように構成した貯水槽用緊急弁の手動復帰装置であって、該手動復帰装置は、前記導水管に介設した切換弁と、少なくとも該切換弁を迂回して上流側の一次側導水管と下流側の二次側導水管とを連通させるバイパス通路と、このバイパス通路に介設した復帰弁と、二次側導水管から分岐されて該二次側導水管と切換弁のパイロット圧力室とを連通させるパイロット配管と、このパイロット配管と二次側導水管との分岐点より上流側の導水管に介設されて前記平常時に弁開し前記異常事態発生時に弁閉する制水弁と、この制水弁と前記分岐点との間で二次側導水から分岐された排水管と、この排水管に介設されて前記平常時および前記異常事態発生後における前記配水本管側の圧力回復時に弁閉し、かつ前記異常事態発生時に弁開する排水弁とを具備し、前記切換弁は、弁体およびこの弁体を常時弁閉方向に付勢する第２付勢手段を備え、前記平常時に前記パイロット圧力室のパイロット圧により前記弁体を第２付勢手段の付勢に抗して移動させて弁開し、前記異常事態発生時に前記第２付勢手段の付勢により前記弁体を前記パイロット圧に抗して移動させて弁閉するように構成され、切換弁の弁閉により前記排水管を通して前記貯水槽用緊急弁の圧力室と該切換弁のパイロット圧力室および二次側導水管内の水を排水し、前記配水本管側の圧力回復に伴う前記排水弁の弁閉後に前記復帰弁の手動弁開により前記パイロット圧を発生させて切換弁を弁開したのちに、前記復帰弁の手動弁閉により前記貯水槽用緊急弁を平常状態に復帰させることを特徴としている。
【００２４】
本発明によれば、配水本管に破損等の異常事態が発生すると、切換弁、復帰弁および制水弁が弁閉されるとともに、排水弁が弁開する。このため、排水管を通して貯水槽用緊急弁の圧力室と切換弁のパイロット圧力室および二次側導水管内の水が排水され、貯水槽用緊急弁を弁閉して、貯水槽への汚水の流入を防止するとともに、貯水槽内に飲料水を確保し、かつ配水本管の通水を確保する。
また、配水本管の破損箇所の補修完了後に配水本管の水圧が回復しても、切換弁、復帰弁および制水弁は弁閉されているので、貯水槽用緊急弁を弁閉状態に保持できる。このため、貯水槽への汚水の流入を防止するとともに、貯水槽内に飲料水を確保し、かつ配水本管の通水を確保できる。また、排水弁の弁閉によって一次側導水管からの排水を防止する。
前記破損箇所の補修時に配水本管に異物が取り込まれても、取り込まれた異物によって汚れた水は配水本管を流下することになるので、汚れた水が誤って貯水槽に入り込むことはない。破損箇所の補修完了後から所定時間経過後、つまり前記汚れた水が下流側本管に流れ切ったと判断した時点で、復帰弁を直接または間接手動操作によって弁開することで、制水弁を弁開し、制水弁の弁開に伴って切換弁を弁開させて、貯水槽用緊急弁の弁本体を弁開した平常時の状態に復帰させることができる。
【００２５】
【発明の実施の形態】
以下、本発明の一実施の形態を図面に基づいて説明する。なお、貯水槽用緊急弁の構造および作用は、図１、図２の比較例の貯水槽用緊急弁と同じであり、本発明の特徴構成は、貯水槽用緊急弁の手動復帰装置ににあるので、前記比較例と同一もしくは相当部分には同一符号を付して詳しい説明は省略する。
【００２６】
図３において、手動復帰装置５０は、導水管２０に介設した切換弁５１と、この切換弁５１を迂回して上流側の一次側導水管２０Ａと下流側の二次側導水管２０Ｂとを連通させるバイパス通路５２と、このバイパス通路５２に介設した復帰弁５３と、パイロット配管５４と、制水弁５５と、排水管５６および排水弁５７を備えている。
【００２７】
切換弁５１は、図４に示すように、弁箱５１Ａと、この弁箱５１Ａの内部に軸方向の移動自在に装入された弁体５１Ｂとを備えている。弁体５１Ｂは弁棒部５１Ｃと、この弁棒部５１Ｃの軸方向一端部に取付けられたピストン部５１Ｄと、弁棒部５１Ｃの軸方向の他端部に取付けられた弁体部５１Ｅを有し、ピストン部５１Ｄはパイロット圧力室５１Ｆに収容され、ピストン部５１Ｄの外周面とパイロット圧力室５１Ｆの内周面とで水封できるように構成されており、弁体部５１Ｅは弁室５１Ｇに収容されて、スプリング５１Ｈにより常時軸方向の一端側に向けて付勢されている。また、弁箱５１Ａにおける弁室５１Ｇの一端部に環状の弁箱シート５１Ｉが設けられ、圧力室５１Ｆに連通するパイロットポート５１Ｊが貫設されている。
【００２８】
一方、弁箱５１Ａには、その周壁を貫通して弁室５１Ｇに通じる流入ポート５１Ｋと流出ポート５１Ｌが形成されており、導水管２０における上流側の一次側導水管２０Ａの出口が流入ポート５１Ｋに接続され、下流側の二次側導水管２０Ｂの入口が流出ポート５１Ｌに接続される。
【００２９】
図３および図４において、パイロット配管５４は二次側導水管２０Ｂから分岐され、その先端部を切換弁５１のパイロットポート５１Ｊに接続することで、二次側導水管２０Ｂと切換弁５１のパイロット圧力室５１Ｆとを連通させている。制水弁５５はダイヤフラム弁によってなり、二次側導水管２０Ｂにおけるパイロット配管５４の分岐点より上流側に介設され、二次側導水管２０Ｂの水圧をダイヤフラム室に取り込んで平常時には弁開し異常事態発生時には弁閉する。排水管５６は二次側導水管２０Ｂにおけるパイロット配管５４の分岐点と制水弁５５の間から分岐される。この排水管５６には、一次側導水管２０Ａの水圧をダイヤフラム室に取り込んで平常時には弁閉し異常事態発生時には弁開する排水弁５７が介設されている。また、復帰弁５３としてハンドルやレバーの手動操作によって直接的に開閉できる構造の弁または電源の遠隔手動操作によって間接的に開閉できる電磁弁もしくは電動弁などが使用される。
【００３０】
前記構成において、貯水槽用緊急弁Ｖおよび手動復帰装置５０の設置直後で、配水本管１の水圧が設定値を超えている平常時では、まず、図３の復帰弁５３を直接または間接手動操作によって予備的に弁開する。これにより、制水弁５５はダイヤフラム室に二次側導水管２０Ｂから高い水圧が取り込まれるので弁開する。排水弁５７のダイヤフラム室には、すでに一次側導水管２０Ａから高い水圧が取り込まれているので弁閉している。このため、二次側導水管２０Ｂおよびパイロット配管５４を介して、図４の切換弁５１におけるパイロット圧力室５１Ｆ内のピストン部５１Ｄに高い水圧が負荷され、弁体５１Ｂをスプリング５１Ｈのばね力に抗して軸方向他端側に向け押圧移動させ、弁室５１Ｇを介して流入ポート５１Ｋと流出ポート５１Ｌを連通させた切換弁５１の弁開が得られる。ここで、復帰弁５３を手動操作によって弁閉する。
【００３１】
このように、切換弁５１と制水弁５５が弁開し、排水弁５７が弁閉することで、設定値を超えている高い水圧をパイロット圧として導水管２０→パイロットポートＰ５の経路で圧力室１６に導入し、弁本体１４のピストン部１４Ａに負荷して貯水槽用緊急弁Ｖを弁開することによって、配水本管１の水を貯水槽２に貯水するとともに、貯水槽２を水道管路の一部として機能させることができる。
【００３２】
たとえば、地震などにより配水本管１に破損等の異常事態が発生して、配水本管１の水圧が設定値以下に低下すると、図５のように制水弁５５のダイヤフラム室には二次側導水管２０Ｂから低い水圧が取り込まれるので弁閉し、排水弁５７のダイヤフラム室には一次側導水管２０Ａから低い水圧が取り込まれるので弁開する。このため、切換弁５１におけるパイロット圧力室５１Ｆおよび貯水槽用緊急弁Ｖの圧力室１６は二次側導水管２０Ｂの一部と排水管５６を介して大気開放される。切換弁５１の弁体５１Ｂは、図６のようにスプリング５１Ｈのばね力によって軸方向一端側に向け移動し、弁体部５１Ｅが弁箱シート５１Ｉに密着して流入ポート５１Ｋと流出ポート５１Ｌを遮断した弁閉状態になる。また、貯水槽用緊急弁Ｖも弁閉されるので、貯水槽２への汚水の流入を防止するとともに、貯水槽２内に飲料水を確保し、かつ配水本管１の通水を確保して配水本管１に接続されている消火栓（図示省略）などの使用可能な状態を得ることができる。
【００３３】
配水本管１の破損箇所の補修完了後の通水により、配水本管１の水圧が回復すると、図７に示すように、排水弁５７のダイヤフラム室に一次側導水管２０Ａから高い水圧が取り込まれているので弁閉する。しかし、切換弁５１、常閉手動弁５３および制水弁５５は弁閉されているので、貯水槽用緊急弁Ｖを弁閉状態に保持できる。このため、たとえ配水本管１における貯水槽用緊急弁Ｖの設置位置よりも上流側の上流側本管１Ａで破損等の異常事態が発生し、この破損箇所の補修時に管内に異物が取り込まれても、この異物によって汚れた水が誤って貯水槽２に入り込むのを確実に防止し、貯水槽２内に飲料水を確保するとともに、配水本管１の通水を確保して、前記消火栓などの使用可能な状態を得ることができる。
【００３４】
前記破損箇所の補修完了後から所定時間経過後、つまり前記汚れた水が下流側本管１Ｂに流れ切ったと判断した時点で、図８のように復帰弁５３を直接または間接手動操作によって弁開する。これにより、制水弁５５はダイヤフラム室に二次側導水管２０Ｂから高い水圧が取り込まれるので弁開する。排水弁５７のダイヤフラム室には、すでに一次側導水管２０Ａから高い水圧が取り込まれているので弁閉している。このため、切換弁５１は前述の理由により図４のように弁開する。
【００３５】
このように、切換弁５１と制水弁５５が弁開し、排水弁５７が弁閉することで、貯水槽用緊急弁Ｖは弁開されるので配水本管１の水を貯水槽２に貯水するとともに、貯水槽２を水道管路の一部として機能させることができる。ここで、復帰弁５３を手動操作によって弁閉することで、図３の平常時の状態に復帰させることができる。
【００３６】
前記実施の形態では、制水弁５５を二次側導水管２０Ｂに介設しているが、図９に示すように、制水弁５５を一次側導水管２０Ａにおけるバイパス通路５２の入口よりも上流位置に介設した構成であってもよい。また、図１０に示すように、制水弁５５を一次側導水管２０Ａにおけるバイパス通路５２の入口と切換弁５１の間に介設した構成であってもよい。さらに、図１１に示すように、制水弁５５を二次側導水管２０Ｂにおけるバイパス通路５２の出口と切換弁５１の間に介設した構成であってもよい。
【００３７】
【発明の効果】
以上説明したように、本発明は、配水本管の破損箇所の補修完了後に配水本管の水圧が回復しても、切換弁、常閉手動弁および制水弁は弁閉されているので、貯水槽用緊急弁を弁閉状態に保持できる。このため、たとえ配水本管における貯水槽用緊急弁の設置位置よりも上流側で破損等の異常事態が発生しても、破損箇所の補修時に混入した異物によって汚れた水が誤って貯水槽に入り込むことはない。
【図面の簡単な説明】
【図１】比較例の平常時の状態を示す構成図である。
【図２】比較例の異常事態発生時の状態を示す構成図である。
【図３】本発明の平常時における一実施の形態を示す構成図である。
【図４】切換弁の弁開状態を示す拡大断面図である。
【図５】本発明の異常事態発生時の一実施の形態を示す構成図である。
【図６】切換弁の弁閉状態を示す拡大断面図である。
【図７】本発明の圧力回復時の一実施の形態を示す構成図である。
【図８】本発明の手動復帰操作時の一実施の形態を示す構成図である。
【図９】本発明の他の実施の形態を示す構成図である。
【図１０】本発明の他の実施の形態を示す構成図である。
【図１１】本発明の他の実施の形態を示す構成図である。
【図１２】従来例の平常時における形態を示す構成図である。
【図１３】従来例の異常事態発生時における形態を示す構成図である。
【図１４】他の従来例の平常時における形態を示す構成図である。
【図１５】図１４のＡ−Ａ線拡大断面図である。
【図１６】他の従来例の異常事態発生時における形態を示す構成図である。
【図１７】図１６のＢ−Ｂ線拡大断面図である。
【符号の説明】
１配水本管
１Ａ上流側本管
１Ｂ下流側本管
２耐震貯水槽（貯水槽）
２Ａ入口
２Ｂ出口
１３筒状の弁箱
１４弁本体
１４Ｄ弁棒部
１５スプリング（第１付勢手段）
１６圧力室
２０導水管
２０Ａ一次側導水管
２０Ｂ二次側導水管
５０手動復帰装置
５１切換弁
５１Ｆ切換弁のパイロット圧力室
５１Ｈスプリング（第２付勢手段）
５２バイパス通路
５３復帰弁
５４パイロット配管
５５制水弁
５６排水管
５７排水弁
Ｐ１第１流入ポート
Ｐ２第１流出ポート
Ｐ３第２流出ポート
Ｐ４第２流入ポート
Ｐ５パイロットポート
Ｖ貯水槽用緊急弁[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is installed in a pipeline between a water distribution main pipe of a water supply facility and an earthquake-resistant water storage tank, and is operated in an emergency when an abnormal situation such as breakage of the water distribution main pipe occurs, thereby preventing inflow of sewage into the water storage tank. The present invention also relates to a manual return device for an emergency valve for a water storage tank that secures water flow through a water distribution main pipe.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, for example, an inflow pipe 3 that connects an upstream main pipe 1A of a water distribution main pipe 1 and an inlet 2A of an earthquake-resistant water storage tank 2 (hereinafter, simply referred to as a water storage tank 2) in a water supply facility as shown in FIG. Of the inflow valve 4, the outflow valve 6 interposed in the outflow pipe 5 that connects the outlet 2 B of the water storage tank 2 to the downstream main pipe 1 B of the water distribution main pipe 1, and the outflow valve 4 in the inflow pipe 3 and the outflow position. The three valves 4, 6, of a bypass valve 8 provided at a position downstream of the outflow valve 6 in the pipe 5, that is, a bypass pipe 7 that communicates the primary side 3A of the inflow pipe 3 with the secondary side 5B of the outflow pipe 5. There is known an emergency valve for a water tank using a water tank 8. In the drawings, V1, V2, and V3 indicate water control valves.
[0003]
In the water tank emergency valve having the above-described configuration, in normal times, the bypass valve 8 and the water control valve V1 are closed, and the inflow valve 4, the outflow valve 6, and the water control valves V2 and V3 are opened as shown in FIG. . For this reason, as shown by the arrow, the water flows into the water storage tank 2 through the route of the main pipe 1A on the upstream side of the water distribution main pipe 1 → the primary side 3A of the inflow pipe 3 → the inflow valve 4 → the secondary side 3B of the inflow pipe 3. And stored. Further, the water that has flowed out of the water storage tank 2 flows down along the route of the primary side 5A of the outflow pipe 5 → the outflow valve 6 → the secondary side 5B of the outflow pipe 5 → the downstream main pipe 1B of the water distribution main pipe 1. In this state, the water storage tank 2 functions as a part of the water pipe.
[0004]
For example, when an abnormal situation such as breakage occurs in the water distribution main 1 due to an earthquake or the like, and the water pressure of the water distribution main 1 drops below a set value, the water pressure is detected and, as shown in FIG. 4 and the outflow valve 6 are closed, and the bypass valve 8 is opened. For this reason, as shown by the arrow, water flows as shown by the arrow in the main pipe 1A on the upstream side of the water distribution main pipe 1 → the primary side 3A of the inflow pipe 3 → the bypass pipe 7 → the secondary side 5B of the discharge pipe 5 → the downstream side of the water distribution main pipe 1. It flows down along the path of the main pipe 1B. Thereby, the inflow of sewage into the water storage tank 2 is prevented, drinking water for emergency water supply is secured in the water storage tank 2, and the water supply main pipe 1 is connected to the water distribution main pipe 1 by securing water flow. A usable state such as a fire hydrant (not shown) can be obtained.
[0005]
However, this kind of water tank emergency valve requires three valves, the inflow valve 4, the outflow valve 6, and the bypass valve 8, and the number of used valves increases, and the probability of malfunctioning increases accordingly. For this reason, if at least one of the three valves malfunctions at the time of occurrence of an abnormal situation, even if the inflow of sewage into the water storage tank 2 can be prevented, the inflow of the water distribution main pipe 1 is not ensured, or Even if water distribution of the water distribution main pipe 1 can be ensured, inconvenience that the inflow of sewage into the water storage tank 2 cannot be prevented occurs. In addition, a large installation space is required.
[0006]
Therefore, there has been provided an emergency valve for a water tank in which the above-mentioned disadvantages have been solved by reducing the number of used valves and reducing the probability of malfunction of the valves. As shown in FIGS. 14 and 15, this type of water tank emergency valve includes one emergency shutoff type butterfly valve 9. The butterfly valve 9 is interposed between the distribution pipe 10A on the water distribution main pipe side and the distribution pipe 10B on the water storage tank side. The distribution pipe 10A on the water distribution main side is connected to the primary side 3A of the inflow pipe 3 and the secondary side 5B of the outflow pipe 5 via the T-shaped pipe 11, and the distribution pipe 10B on the water storage tank side is connected via the T-shaped pipe 12. To the secondary side 3B of the inflow pipe 3 and the primary side 5A of the outflow pipe 5. The distribution pipe 10A on the water distribution main side is partitioned into an upper passage 5B1 and a lower passage 3A1, and the distribution pipe 10B on the water storage tank side is partitioned into an upper passage 5A1 and a lower passage 3B1. ing. The T-tube 11 communicates the primary side 3A of the inflow pipe 3 with the lower passage 3A1 of the water distribution main pipe 10A, and the secondary side 5B of the outflow pipe 5 and the water main pipe side. A partition wall 11A is provided for communicating with the upper passage 5B1 of the distribution pipe 10A. The T-shaped pipe 12 is provided with the secondary side 3B of the inflow pipe 3 and the lower passage 3B1 of the water distribution tank 10B. A partition wall 11A is provided to allow communication between the primary side 5A of the outflow pipe 5 and the upper passage 5A1 in the distribution pipe 10B on the water distribution main pipe side. In the figure, V1 indicates a water control valve.
[0007]
With such a configuration, in normal times, the butterfly valve 9 is opened and the water control valve V1 is closed as shown in FIGS. For this reason, as shown by the arrow, the water flows from the upstream main pipe 1A of the water distribution main pipe 1 → the primary side 3A of the inflow pipe 3 → the T-shaped pipe 11A → the lower passage 3A1 of the distribution pipe 10A on the water distribution main pipe side → Butterfly valve 9 → lower passage 3B1 of water storage tank side, lower passage 3B1 → secondary flow 3B of inflow pipe 3 flows into water storage tank 2 and is stored therein. Further, the water flowing out of the water storage tank 2 is supplied to the primary side 5A of the outflow pipe 5 → the T-shaped pipe 12A → the upper passage 5A1 of the water distribution pipe 10B → the butterfly valve 9 → the water distribution main pipe 10A. The water flows down the upper passage 5B1 → the T-shaped pipe 11A → the secondary side 5B of the outflow pipe 5 → the downstream main pipe 1B of the water distribution main pipe 1. In this state, the water storage tank 2 functions as a part of the water pipe.
[0008]
For example, when an abnormal situation such as breakage occurs in the water distribution main 1 due to an earthquake or the like and the water pressure of the water distribution main 1 drops below a set value, the water pressure is detected and, as shown in FIG. 16 and FIG. The butterfly valve 9 closes. For this reason, as shown by the arrow, the water flows from the upstream main pipe 1A of the water distribution main pipe 1 → the primary side 3A of the inflow pipe 3 → the T-shaped pipe 11A → the lower passage 3A1 of the distribution pipe 10A on the water distribution main pipe side → Before the butterfly valve 9 → the passage 5B1 on the upper side of the distribution pipe 10A on the water distribution main pipe side → the T-shaped pipe 11A → the secondary side 5B of the outflow pipe 5 → the downstream main pipe 1B of the water distribution main pipe 1 flows down. Thereby, the inflow of sewage into the water storage tank 2 is prevented, drinking water for emergency water supply is secured in the water storage tank 2, and the water supply main pipe 1 is connected to the water distribution main pipe 1 by securing water flow. A usable state such as a fire hydrant (not shown) can be obtained.
[0009]
However, the emergency valve for a water tank devised so as to reduce the number of used valves includes a water distribution main pipe-side branch pipe 10A divided into an upper passage 5B1 and a lower passage 3A1, and an upper passage 5A1. The distribution pipe 10B on the water storage tank side divided into the lower passage 3B1, the primary side 3A of the inflow pipe 3 and the lower passage 3A1 of the distribution pipe 10A on the water distribution main side communicate with each other, and the outflow pipe 5 The T-shaped pipe 11 provided with a partition wall 11A for communicating the secondary side 5B and the upper passage 5B1 in the distribution pipe 10A on the water distribution main side, the secondary side 3B of the inflow pipe 3 and the lower part of the distribution pipe 10B on the water storage tank side. A T-shaped pipe 12 provided with a partition wall 12A for communicating the passage 3B1 on the side and the primary side 5A of the outflow pipe 5 and the upper passage 5A1 in the distribution pipe 10B on the water storage tank side is required. Moreover, the distribution pipe 10A on the water distribution main pipe side, the distribution pipe 10B on the water storage tank side, the T-shaped pipe 11 and the T-shaped pipe 12 each have a complicated structure, so that it is difficult to manufacture them.
[0010]
In view of this, the present applicant has disclosed in Japanese Patent Application No. Hei 9-146496 that the number of valves used is reduced, the probability of the above-described inconvenience occurring when an abnormal situation occurs is reduced, and the reliability is increased, and the installation space is increased. There has already been provided an emergency valve for a water tank that can be easily manufactured without using a piping material such as a diversion tube or a T-tube having a reduced size and a complicated structure.
[0011]
As shown in FIGS. 1 and 2, this type of emergency valve for a water tank includes a cylindrical valve box 13 and a valve body 14 that is axially movably mounted inside the valve box 13. And The valve body 14 has a valve stem 14D, a piston 14A attached to one axial end of the valve stem 14D, and a first valve body biased to the other axial end of the valve stem 14D. Portion 14B, a piston portion 14F, and a second valve body portion 14C attached to a substantially central portion of the valve rod portion 14D in the axial direction. The piston portion 14A, the first valve body portion 14B, and the second valve body portion 14C The outer peripheral surfaces of the piston portions 14A and 14F and the inner peripheral surface of the valve box 13 can be water-sealed.
[0012]
Inside the valve box 13, an annular first valve box sheet 13A, an annular second valve box sheet 13B and an annular third valve box sheet 13C are provided, and the piston portion 14A is provided with an annular first valve box sheet 13A. , The piston portion 14F is located in the biasing chamber 17 at the other axial end, and the first valve body portion 14B is located near the biasing chamber 17. are doing. Further, the second valve body portion 14C is located in the inflow chamber 18 between the annular first valve box sheet 13A and the annular second valve box sheet 13B, and the annular second valve box sheet 13B and the annular second valve box sheet 13B. An outflow chamber 19 is formed between the third valve box sheets 13C.
[0013]
On the other hand, the valve box 13 is formed with a first inflow port P1 penetrating through the peripheral wall thereof and leading to the inflow chamber 18 and a first outflow port P2 leading to the outflow chamber 19. A second outflow port P3 that penetrates a peripheral wall 180 ° away from the forming position in the circumferential direction and communicates with the inflow chamber 18 via the first valve box sheet 13A, and an outflow chamber via the third valve box sheet 13C. A second inflow port P4 leading to 19 is formed. Further, a pilot port P5 is formed through one end of the valve box 13 and communicates with the pressure chamber 16. A biasing means 15 made of a spring is loaded in the biasing chamber 17, and a valve body 14 is provided. Is constantly biased toward one end in the axial direction.
[0014]
The water storage tank emergency valve V is provided between the water distribution main pipe 1 and the water storage tank 2 in the water supply facility. That is, the upstream main pipe 1A of the water distribution main pipe 1 is connected to the first inflow port P1 via the primary side 3A of the inflow pipe 3, and the downstream main pipe 1B of the water distribution main pipe 1 is connected to the secondary side of the outflow pipe 5. 5B, is connected to the first outflow port P2, the inlet 2A of the water storage tank 2 is connected to the second outflow port P3 through the secondary side 3B of the inflow pipe 3, and the outlet 2B of the water storage tank 2 is outflow. The pipe 5 is connected to the second inflow port P4 via the primary side 5A. The upstream main pipe 1 A of the water distribution main pipe 1 is connected to the pilot port P 5 via the water conduit pipe 20. In the figure, V1 indicates a water control valve.
[0015]
On the other hand, outside the urging chamber 17, a valve body opening degree indicating device 30 extending to the other end side in the axial direction is provided. The opening degree indicating device 30 of the valve body communicates with the inside of the biasing chamber 17 through a valve rod insertion hole 17 a penetrating through the outer end wall portion 17 A of the biasing chamber 17, and A cylindrical valve stem cover 30A extending outward and attached to the other end in the axial direction, and a valve stem portion 14D inserted through the stem insertion hole 17a and inserted into the valve stem cover 30A, protruding outside the valve box. A portion 14d and a fan-shaped or disk-shaped valve opening indicating member 30B fixed to the valve box outer protrusion 14d (however, in the present embodiment, the fan-shaped valve opening indicating member 30B is fixed). And a visual window 30C of the valve opening indicating member corresponding to the outer peripheral portion of the valve opening indicating member 30B and extending in the axial direction and penetrating the peripheral wall of the valve stem cover 30A. The visual window 3 is provided on the peripheral wall of the valve stem cover 30A near the visual window 30C of the valve opening degree indicating member. The character "open" is displayed on the other end (one side) in the axial direction of C, and the character "closed" is displayed on one end (the other side) in the axial direction of the viewing window 30C. .
[0016]
Further, this kind of water tank emergency valve V has an automatic return device 40. The automatic return device 40 is interposed in the water pipe 20 and takes in the water pressure of the water pipe 20 into the diaphragm chamber to open the valve as shown in FIG. 1 in the normal state, and as shown in FIG. 2 when the abnormal situation occurs. A water control valve 41 composed of a diaphragm valve that is closed, a drain pipe 42 branched from the water guide pipe 20 on the downstream side of the water control valve 41, The water pressure upstream of the water control valve 41 is taken into the diaphragm chamber, and the drain valve 43 is constituted by a diaphragm valve which is normally closed as shown in FIG. 1 and which is opened as shown in FIG. And is constituted by.
[0017]
In the above configuration, the water pressure of the water distribution main pipe 1 and the water conveyance pipe 20 in a normal state exceeds the set value. Since the high water pressure exceeding the set value is taken into the diaphragm chamber of the water control valve 41 from the water pipe 20, the valve is opened, and the high water pressure exceeding the set value from the water pipe 20 is also supplied to the diaphragm chamber of the drain valve 43. The valve is closed as it is taken in. For this reason, the high water pressure exceeding the set value can be introduced as pilot pressure into the pressure chamber 16 through the path from the water pipe 20 to the pilot port P5, and can be applied to the piston portion 14A of the valve body 14. When a high pilot pressure is applied to the piston portion 14A of the valve body 14, the valve body 14 is moved to the other axial side of the valve box 13 against the urging of the urging means 15, and the emergency for the water tank is started. The valve V is opened. Thereby, the first inflow port P1 and the second outflow port P3 communicate with each other via the inflow chamber 18, and the first outflow port P2 and the second inflow port P4 communicate with each other via the outflow chamber 19. For this reason, as shown by an arrow, water flows in the upstream main pipe 1A of the water distribution main pipe 1 → the primary side 3A of the inflow pipe 3 → the first inflow port P1 → the inflow chamber 18 →→ the second outflow port P3 → the inflow pipe 3 Flows into the water storage tank 2 through the path of the secondary side 3B and is stored. Further, water that has flowed out of the water storage tank 2 is discharged from the primary side 5A of the outflow pipe 5 → the second inflow port P4 → the outflow chamber 19 → the first outflow port P2 → the secondary side 5B of the outflow pipe 5 → downstream of the water distribution main pipe 1. It flows down along the route of the side main pipe 1B. In this state, the water storage tank 2 functions as a part of the water pipe.
[0018]
In this case, the valve opening degree indicating member 30B fixed to the valve box outer projection 14d of the valve stem 14D is a fully opened instruction position biased to one axial side of the cylindrical valve stem cover 30A, that is, the display character. The fully opened state of the valve body 14 can be confirmed by visually recognizing the valve opening degree indicating member 30B at the position corresponding to “open” and at the fully opened instruction position from the visual window 30C.
[0019]
For example, when an abnormal situation such as breakage of the water distribution main pipe 1 occurs due to an earthquake or the like and the water pressure of the water distribution main pipe 1 falls below the set value, the diaphragm chamber of the water control valve 41 is set below the set value from the water guide pipe 20. , The valve is closed, and the diaphragm chamber of the drain valve 43 is also opened because a low water pressure equal to or lower than a set value is taken in from the water guide pipe 20. Therefore, the pressure chamber 16 is opened to the atmosphere via a part of the water pipe 20 and the drain pipe 42. As a result, as shown in FIG. 2, the urging of the urging means 15 causes the second valve body portion 14C to come into contact with the first valve box sheet 13A, and the first valve body portion 14B to come into contact with the third valve box sheet 13C. The valve body 14 is moved to one end in the axial direction of the valve box 13 until the contact position. Thereby, the first inflow port P1 and the first outflow port P2 communicate with each other via the inflow chamber 18 and the outflow chamber 19. For this reason, as shown by an arrow, the water flows in the upstream main pipe 1A of the water distribution main pipe 1 → the primary side 3A of the inflow pipe 3 → the first inflow port P1 → the inflow chamber 18 → the outflow chamber 19 → the first outflow port P2 → It flows down from the secondary side 5B of the outflow pipe 5 to the downstream main pipe 1B of the water distribution main pipe 1. Therefore, the inflow of sewage into the water storage tank 2 is prevented, drinking water for emergency water supply is secured in the water storage tank 2, and the fire hydrant connected to the water distribution main pipe 1 by ensuring the water distribution of the water distribution main pipe 1. A usable state such as (not shown) can be obtained.
[0020]
However, in the above-described automatic return device 40, the damaged portion of the water distribution main pipe 1 is repaired after the occurrence of the abnormal situation, so that the water pressure of the water distribution main pipe 1 is restored to a value exceeding the set value, and at the same time, the automatic recovery is performed. Then, the water tank emergency valve V is returned to the normal state shown in FIG. For this reason, the muddy water containing the earth and sand etc. which was taken in at the time of the repair of the water distribution main pipe 1 flows into the water storage tank 2, and the water in the water storage tank 2 cannot be supplied as drinking water for emergency water supply. There is a fear.
[0021]
[Problems to be solved by the invention]
In other words, in the automatic return device for the water tank emergency valve that has solved the drawbacks of the conventional water tank emergency valve, the water pressure of the water main is restored automatically at the same time as the water pressure of the water main recovers after the repair of the damaged part of the water main is completed. Since the valve body will be opened and the water storage tank will function as a part of the water distribution pipeline, if an abnormal situation such as breakage occurs upstream of the location of the water storage tank emergency valve in the water distribution main pipe, There is a possibility that water contaminated by foreign matter taken into the water distribution main line when repairing the damaged part may accidentally enter the water storage tank, making it impossible to supply the water in the water storage tank as drinking water for emergency water supply. I have.
[0022]
Therefore, the present invention provides a water tank emergency valve that solves the drawbacks of the conventional water tank emergency valve, and an abnormal situation such as breakage occurs upstream of the location of the water tank emergency valve in the distribution main pipe. The object of the present invention is to provide a water tank emergency valve manual reset device that can reliably prevent water contaminated by foreign matter from accidentally entering the water tank even when foreign matter is taken into the pipe when repairing a damaged part. It is what it was.
[0023]
[Means for Solving the Problems]
In order to achieve the above object, a manual return device for an emergency valve for a water storage tank according to the present invention includes a first inflow port communicating with an upstream main pipe of a water distribution main pipe on a peripheral wall portion of a cylindrical valve box; A first outflow port communicating with the main pipe downstream of the pipe, a second outflow port communicating with the inlet of the water storage tank, and a second inflow port communicating with the outlet of the water storage tank are provided, and the axial movement inside the valve box is provided. A valve body having a valve rod portion is freely inserted therein, a first urging means for constantly urging the valve body to one side in the axial direction, and a valve against the urging of the first urging means. A pressure chamber for urging the main body to the other side in the axial direction, and a water guide pipe for communicating the pressure chamber with the water distribution main pipe side, and in normal times when the water pressure on the water distribution main pipe side exceeds an operation set value. Moving the valve body to one axial side of the valve box against the urging of the first urging means by the water pressure of the pressure chamber. With the valve in an open state in which the first inflow port and the second outflow port and the first outflow port and the second inflow port communicate with each other, the water storage tank functions as a part of a water distribution pipe, and When an abnormal situation occurs in which the water pressure on the pipe side drops below the operation set value, the valve body is moved to the other axial side of the valve box against the water pressure in the pressure chamber by the urging of the first urging means. Moving the first inflow port and the first outflow port in a closed state to prevent inflow of sewage into the water storage tank, secure drinking water in the water storage tank, and distribute the water; A manual return device for an emergency valve for a water storage tank configured to secure water flow through a main pipe, wherein the manual return device bypasses at least a switching valve provided in the water pipe and at least the switching valve. A bypass that connects the upstream primary water pipe to the downstream secondary water pipe A passage, a return valve interposed in the bypass passage, a pilot pipe branched from the secondary-side water pipe and communicating the secondary-side water pipe with the pilot pressure chamber of the switching valve, A water control valve interposed in the water pipe upstream of the branch point with the side water pipe, which opens during normal times and closes when the abnormal situation occurs; and a water control valve between the water control valve and the branch point. A drain pipe branched from the secondary water conduit, interposed in the drain pipe, closing the valve at the time of pressure recovery on the water distribution main side at normal times and after the occurrence of the abnormal situation, and opening the valve at the time of the abnormal situation The switching valve includes a valve element and second urging means for constantly urging the valve element in a valve closing direction, and the valve element is normally operated by the pilot pressure of the pilot pressure chamber in the normal state. Is moved against the urging of the second urging means to open the valve, When the abnormal condition occurs, the valve body is moved against the pilot pressure by the urging of the second urging means to close the valve, and the water storage tank is passed through the drainage pipe by closing the switching valve. Water in the pressure chamber of the emergency valve, the pilot pressure chamber of the switching valve, and the secondary water pipe, and manually open the return valve after the drain valve is closed due to pressure recovery on the water distribution main side. Then, after the pilot pressure is generated to open the switching valve, the emergency valve for the water storage tank is returned to a normal state by manually closing the return valve.
[0024]
According to the present invention, when an abnormal situation such as breakage occurs in the water distribution main pipe, the switching valve, the return valve, and the water control valve are closed, and the drain valve is opened. For this reason, the water in the pressure chamber of the water tank emergency valve, the pilot pressure chamber of the switching valve, and the secondary side water pipe is drained through the drain pipe, and the emergency valve for the water tank is closed. Prevent inflow, secure drinking water in the water storage tank, and secure water flow through the distribution mains.
Also, even if the water pressure in the distribution mains is restored after the repair of the damaged part of the distribution mains is completed, the switching valve, the return valve and the water control valve are closed, so the emergency valve for the water tank is closed. Can be retained. Therefore, it is possible to prevent the inflow of sewage into the water storage tank, secure drinking water in the water storage tank, and secure water flow through the water distribution main pipe. In addition, drainage from the primary water pipe is prevented by closing the drain valve.
Even if foreign matter is taken into the distribution main when repairing the damaged portion, the water contaminated by the foreign matter flows down the distribution main, so that the dirty water does not accidentally enter the water storage tank. . After a lapse of a predetermined time from completion of repair of the damaged portion, that is, when it is determined that the contaminated water has completely flowed to the downstream main pipe, the return valve is opened by direct or indirect manual operation to open the water control valve. The valve is opened, the switching valve is opened with the opening of the water control valve, and the valve body of the water storage tank emergency valve can be returned to the normal state where the valve is opened.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings. The structure and operation of the water storage tank emergency valve are the same as those of the water storage tank emergency valve of the comparative example shown in FIGS. 1 and 2, and the characteristic configuration of the present invention is applied to a manual recovery device of the water storage tank emergency valve. Therefore, the same or corresponding parts as those of the comparative example are denoted by the same reference numerals, and detailed description is omitted.
[0026]
In FIG. 3, the manual return device 50 includes a switching valve 51 interposed in the water pipe 20, a primary water pipe 20 A on the upstream side bypassing the switching valve 51, and a secondary water pipe 20 B on the downstream side. A bypass passage 52 to be communicated with, a return valve 53 provided in the bypass passage 52, a pilot pipe 54, a water control valve 55, a drain pipe 56 and a drain valve 57 are provided.
[0027]
As shown in FIG. 4, the switching valve 51 includes a valve box 51A and a valve body 51B that is movably inserted in the valve box 51A in the axial direction. The valve body 51B has a valve stem 51C, a piston 51D attached to one axial end of the valve stem 51C, and a valve body 51E attached to the other axial end of the valve stem 51C. The piston portion 51D is accommodated in the pilot pressure chamber 51F, and is configured so that the outer peripheral surface of the piston portion 51D and the inner peripheral surface of the pilot pressure chamber 51F can be sealed with water. The valve body 51E is connected to the valve chamber 51G. It is housed and constantly urged toward one end in the axial direction by a spring 51H. An annular valve box sheet 51I is provided at one end of the valve chamber 51G in the valve box 51A, and a pilot port 51J communicating with the pressure chamber 51F is provided therethrough.
[0028]
On the other hand, the valve box 51A is formed with an inflow port 51K and an outflow port 51L that penetrate the peripheral wall and communicate with the valve chamber 51G, and the outlet of the upstream primary water pipe 20A in the water pipe 20 is connected to the inflow port 51K. , And the inlet of the secondary water conduit 20B on the downstream side is connected to the outflow port 51L.
[0029]
3 and 4, the pilot pipe 54 is branched from the secondary water conduit 20B, and the distal end thereof is connected to the pilot port 51J of the switching valve 51, so that the pilot pipe of the secondary water conduit 20B and the switching valve 51 is connected. The pressure chamber 51F is communicated with the pressure chamber 51F. The water control valve 55 is composed of a diaphragm valve, and is interposed at a position upstream of the branch point of the pilot pipe 54 in the secondary-side water conduit 20B. The water pressure of the secondary-side water conduit 20B is taken into the diaphragm chamber and is normally opened. The valve closes when an abnormal situation occurs. The drain pipe 56 is branched from the branch point of the pilot pipe 54 in the secondary water conduit 20 B and between the water control valve 55. The drainage pipe 56 is provided with a drainage valve 57 which takes in the water pressure of the primary side water guide pipe 20A into the diaphragm chamber, closes the valve at normal times, and opens the valve when an abnormal situation occurs. As the return valve 53, a valve having a structure that can be directly opened and closed by manual operation of a handle or a lever, a solenoid valve or an electric valve that can be indirectly opened and closed by remote manual operation of a power supply, or the like is used.
[0030]
In the above configuration, immediately after the water tank emergency valve V and the manual return device 50 are installed, in a normal state where the water pressure of the water distribution main pipe 1 exceeds a set value, first, the return valve 53 of FIG. The valve is preliminarily opened by the operation. Thereby, the water control valve 55 is opened because a high water pressure is taken into the diaphragm chamber from the secondary water conduit 20B. The diaphragm chamber of the drain valve 57 is closed because a high water pressure has already been taken in from the primary water conduit 20A. For this reason, a high water pressure is applied to the piston portion 51D in the pilot pressure chamber 51F of the switching valve 51 of FIG. 4 via the secondary water conduit 20B and the pilot pipe 54, and the valve body 51B is subjected to the spring force of the spring 51H. The switching valve 51 is pressed and moved toward the other end in the axial direction to open the switching valve 51 in which the inflow port 51K and the outflow port 51L communicate with each other through the valve chamber 51G. Here, the return valve 53 is manually closed.
[0031]
As described above, the switching valve 51 and the water control valve 55 are opened, and the drain valve 57 is closed, so that the high water pressure exceeding the set value is used as the pilot pressure as the pilot pressure in the path from the water pipe 20 to the pilot port P5. By introducing the water into the chamber 16 and loading the piston portion 14A of the valve body 14 to open the water tank emergency valve V, the water in the water distribution main pipe 1 is stored in the water tank 2 and the water tank 2 is filled with water. It can function as a part of a pipeline.
[0032]
For example, when an abnormal situation such as breakage of the water distribution main pipe 1 occurs due to an earthquake or the like and the water pressure of the water distribution main pipe 1 falls below a set value, as shown in FIG. The valve is closed because a low water pressure is taken in from the side water pipe 20B, and the diaphragm chamber of the drain valve 57 is opened because a low water pressure is taken from the primary water pipe 20A. Therefore, the pilot pressure chamber 51F of the switching valve 51 and the pressure chamber 16 of the water storage tank emergency valve V are opened to the atmosphere via a part of the secondary water conduit 20B and the drain pipe 56. As shown in FIG. 6, the valve body 51B of the switching valve 51 moves toward one end in the axial direction by the spring force of the spring 51H, and the valve body 51E comes into close contact with the valve box sheet 51I to connect the inflow port 51K and the outflow port 51L. The shut-off valve is closed. In addition, since the water tank emergency valve V is also closed, the inflow of sewage into the water tank 2 is prevented, the drinking water is secured in the water tank 2, and the water distribution of the water distribution main pipe 1 is secured. Thus, a usable state such as a fire hydrant (not shown) connected to the water distribution main pipe 1 can be obtained.
[0033]
When the water pressure of the water distribution main pipe 1 is restored by the flow of water after the repair of the damaged part of the water distribution main pipe 1 is completed, the high water pressure is taken into the diaphragm chamber of the drain valve 57 from the primary water pipe 20A as shown in FIG. The valve is closed. However, since the switching valve 51, the normally-closed manual valve 53, and the water control valve 55 are closed, the water storage tank emergency valve V can be held in the valve closed state. For this reason, even if an abnormal situation such as breakage occurs in the upstream main pipe 1A on the upstream side of the installation position of the storage tank emergency valve V in the water distribution main pipe 1, foreign matter is taken into the pipe when repairing the damaged portion. However, it is possible to reliably prevent water contaminated by the foreign matter from accidentally entering the water storage tank 2 and secure drinking water in the water storage tank 2 and secure water flow through the water distribution main pipe 1. It is possible to obtain a usable state such as.
[0034]
After a lapse of a predetermined time from completion of the repair of the damaged portion, that is, when it is determined that the contaminated water has completely flowed to the downstream main pipe 1B, the return valve 53 is opened by direct or indirect manual operation as shown in FIG. I do. Thereby, the water control valve 55 is opened because a high water pressure is taken into the diaphragm chamber from the secondary water conduit 20B. The diaphragm chamber of the drain valve 57 is closed because a high water pressure has already been taken in from the primary water conduit 20A. For this reason, the switching valve 51 opens as shown in FIG. 4 for the above-described reason.
[0035]
As described above, the switching valve 51 and the water control valve 55 are opened, and the drain valve 57 is closed, so that the water storage tank emergency valve V is opened, so that the water in the water distribution main pipe 1 is transferred to the water storage tank 2. In addition to storing water, the water storage tank 2 can function as a part of a water pipe. Here, by returning the return valve 53 by manual operation, it is possible to return to the normal state of FIG.
[0036]
In the above embodiment, the water control valve 55 is interposed in the secondary water conduit 20B. However, as shown in FIG. 9, the water control valve 55 is located closer to the inlet of the bypass passage 52 in the primary water conduit 20A. A configuration interposed at the upstream position may be used. Further, as shown in FIG. 10, a configuration in which the water control valve 55 is interposed between the inlet of the bypass passage 52 and the switching valve 51 in the primary water conduit 20 A may be employed. Further, as shown in FIG. 11, a configuration in which the water control valve 55 is interposed between the outlet of the bypass passage 52 in the secondary water conduit 20 B and the switching valve 51 may be employed.
[0037]
【The invention's effect】
As described above, according to the present invention, the switching valve, the normally closed manual valve, and the water control valve are closed even if the water pressure of the water distribution main is recovered after the repair of the damaged portion of the water distribution main is completed. The water storage tank emergency valve can be kept closed. For this reason, even if an abnormal situation such as breakage occurs upstream of the location of the water tank emergency valve in the water distribution main line, water contaminated by foreign matter mixed in when repairing the damaged part is mistakenly injected into the water tank. It does not enter.
[Brief description of the drawings]
FIG. 1 is a configuration diagram illustrating a normal state of a comparative example.
FIG. 2 is a configuration diagram illustrating a state when an abnormal situation occurs in a comparative example.
FIG. 3 is a configuration diagram showing one embodiment of a normal state of the present invention.
FIG. 4 is an enlarged sectional view showing a valve open state of a switching valve.
FIG. 5 is a configuration diagram showing an embodiment of the present invention when an abnormal situation occurs.
FIG. 6 is an enlarged cross-sectional view illustrating a switching valve in a closed state.
FIG. 7 is a configuration diagram showing an embodiment of the present invention at the time of pressure recovery.
FIG. 8 is a configuration diagram showing one embodiment of a manual return operation of the present invention.
FIG. 9 is a configuration diagram showing another embodiment of the present invention.
FIG. 10 is a configuration diagram showing another embodiment of the present invention.
FIG. 11 is a configuration diagram showing another embodiment of the present invention.
FIG. 12 is a configuration diagram showing a normal state of a conventional example.
FIG. 13 is a configuration diagram illustrating a conventional example when an abnormal situation occurs.
FIG. 14 is a configuration diagram showing a form of another conventional example in a normal state.
FIG. 15 is an enlarged sectional view taken along line AA of FIG. 14;
And FIG. 16 is a configuration diagram showing a form of another conventional example when an abnormal situation occurs.
FIG. 17 is an enlarged sectional view taken along line BB of FIG. 16;
[Explanation of symbols]
1 Water distribution mains
1A Main pipe on the upstream side
1B Downstream main pipe
2 Seismic water tank (water tank)
2A entrance
2B exit
13 Cylindrical valve box
14 Valve body
14D valve stem
15 Spring (first biasing means)
16 pressure chamber
20 water pipe
20A Primary water conduit
20B Secondary water conduit
50 Manual return device
51 Switching valve
51F Pilot pressure chamber for switching valve
51H spring (second biasing means)
52 Bypass passage
53 Return valve
54 Pilot piping
55 Water control valve
56 drainpipe
57 drain valve
P1 1st inflow port
P2 1st outflow port
P3 2nd outflow port
P4 2nd inflow port
P5 Pilot port
V Emergency valve for water tank

Claims

A first inflow port communicating with the upstream main pipe of the water distribution main pipe, a first outflow port communicating with the downstream main pipe of the water distribution main pipe, and a second outflow communicating with the inlet of the water storage tank on the peripheral wall of the cylindrical valve box. A port and a second inflow port leading to the outlet of the reservoir,
A valve body having a valve rod portion movably in the axial direction is inserted inside the valve box,
First biasing means for constantly biasing the valve body to one side in the axial direction; a pressure chamber for biasing the valve body to the other side in the axial direction against the biasing of the first biasing means; A water pipe that communicates the pressure chamber with the water distribution main pipe side,
In normal times when the water pressure on the water distribution main side exceeds the operation set value, the valve body is moved to one side in the axial direction of the valve box against the urging of the first urging means by the water pressure of the pressure chamber. In a valve-open state in which the first inflow port and the second outflow port and the first outflow port and the second inflow port communicate with each other, the water storage tank functions as a part of a water distribution pipe,
When an abnormal situation occurs in which the water pressure on the water distribution main pipe side falls below the operation set value, the valve body is moved in the axial direction of the valve box against the water pressure in the pressure chamber by the urging of the first urging means. Moved to the other side, preventing the inflow of sewage into the water storage tank in a valve closed state that communicates the first inflow port and the first outflow port, to secure drinking water in the water storage tank, And a manual return device of the water storage tank emergency valve configured to ensure the flow of water in the water distribution mains,
The manual return device is provided with a switching valve provided in the water pipe, a bypass passage that bypasses at least the switching valve and communicates the upstream primary water pipe and the downstream secondary water pipe, A return valve interposed in the bypass passage, a pilot pipe branched from the secondary-side water pipe and communicating the secondary-side water pipe with the pilot pressure chamber of the switching valve, and the pilot pipe and the secondary-side water pipe. A water control valve which is interposed in the water conveyance pipe upstream of the branch point and opens at normal times and closes at the time of occurrence of the abnormal condition; A branched drain pipe, and a drain valve interposed in the drain pipe, which closes when the pressure is restored on the water distribution main side at normal times and after the occurrence of the abnormal situation, and opens when the abnormal situation occurs. With
The switching valve includes a valve body and a second biasing unit that constantly biases the valve body in a valve closing direction.
In the normal state, the valve body is moved by the pilot pressure of the pilot pressure chamber against the urging of the second urging means to open the valve,
When the abnormal situation occurs, the valve body is moved against the pilot pressure by the urging of the second urging means to close the valve,
Draining the water in the pressure chamber of the water storage tank emergency valve and the pilot pressure chamber of the switching valve and the secondary water conduit through the drainage pipe by closing the switching valve;
After the drain valve is closed due to pressure recovery on the water distribution main side, the pilot pressure is generated by manual opening of the return valve to open the switching valve, and then the return valve is manually closed by the manual valve closing. A manual reset device for a water tank emergency valve, wherein the water tank emergency valve is returned to a normal state.