【０００１】
【発明の属する技術分野】
本発明は、金属材からなる弁箱シートと弁体シートとを備えたメタルシートバタフライ弁に関する。
【０００２】
【従来の技術】
従来、この種のメタルシートバタフライ弁としては、例えば図１２〜図１７に示すものがある。すなわち、図１２〜図１４に示すように、上記メタルシートバタフライ弁１は、弁箱２と、この弁箱２の流路軸心３に対して直交する軸心４廻りに回転自在な一対の弁棒５と、これら弁棒５に設けられた弁体６とで構成されている。
【０００３】
上記弁箱２の内部には、円筒状の薄肉金属材からなる弁箱シート７が上記流路軸心３と同心状に配置されている。また、弁箱２には一対のボス部８が形成され、両ボス部８には、弁箱２の内外面に開口するボス孔部８ａ（図１７参照）が形成されている。図１５〜図１７に示すように、上記両弁棒５はそれぞれ、上記ボス部８のボス孔部８ａと弁箱シート７に形成された一対の貫通孔９とに挿通され、上記ボス部８に挿入された円筒状の軸受部材１０（ブッシュ）によって回転自在に保持されている。
【０００４】
上記弁体６は複数のピン（図示省略）によって上記一対の弁棒５間に連結されており、弁体６の周縁部には、弁箱シート７の内周面に水密に摺接する金属材からなる弁体シート１１が設けられている。尚、図１４の実線に示すように、上記弁体６を全閉した状態で、弁体シート１１は、弁箱シート７への焼付きを防止するために、弁体６の流路軸心３に直交し且つ上記軸心４を含む断面に対して僅かな角度α（例えばα＝約３°）だけ開方向へ傾斜している。
【０００５】
図１２，図１５に示すように、上記弁体６と両軸受部材１０の内側端部との間にはそれぞれ、一対のリング状の軸封シール材１２，１３が配置されている。このうち、図１５〜図１７に示すように、軸受部材１０側（外側）に配置された弁箱側軸封シール材１２は、内側端部が弁箱シート７の貫通孔９に挿入され、弁棒５と弁箱シート７との間をシールしている。尚、弁箱側軸封シール材１２は、ゴム（ＣＲ）等の弾性材の内部に芯金を備え、弁体側軸封シール材１３に接触する接触面（内端面）にフッ素樹脂をコーティングしたものである。また、弁体６側（すなわち弁体６と弁箱側軸封シール材１２との間）に配置された弁体側軸封シール材１３は金属材からなる。
【０００６】
また、両ボス部８にはそれぞれ、軸受部材１０を介して弁箱側軸封シール材１２を弁体側軸封シール材１３へ押圧する締付手段１４が設けられている。これら締付手段１４は、軸受部材１０の外側端部に配置された環状の押え板１５と、この押え板１５をボス部８に装着して弁体側軸封シール材１３側へ締め付ける複数の締付ボルト１６とで構成されている。
【０００７】
また、図１３〜図１６に示すように、上記弁箱２と弁箱シート７の外周面との間には、弁箱２の内周面と弁箱シート７との間隙１７を流路の上流側と下流側とにシールする円環状のＯリング１８（弁箱シール材）が設けられている。尚、図１４の実線で示すように、Ｏリング１８は、弾性体で形成されており、全閉した弁体６の弁体シート１１に弁箱シート７を介してほぼ対向している。
【０００８】
図１６に示すように、上記Ｏリング１８は半円状の一対のシール片１８ａ，１８ｂに２分割されており、図１４に示すように、これらシール片１８ａ，１８ｂは弁箱２の内周面に形成された取付用溝１９内に嵌め込まれている。図１６の実線で示すように、上記両シール片１８ａ，１８ｂの各端部は弁箱側軸封シール材１２の外周面に食い込んで圧接している。
【０００９】
尚、図１３，図１４に示すように、弁箱２内には、弁箱シート７を流路軸心３の方向において固定するリング状のストッパー２０が弁箱シート７の上流側端部と下流側端部とに隣接して配置され、ボルト２１（図１４参照）によって弁箱２に取付けられている。
【００１０】
これによると、図１４の実線で示すように、弁体６を全閉した場合、弁体シート１１が弁箱シート７の内周面に水密に摺接する。この際、弁箱２内の流路の上流側から弁箱シート７の外周面と弁箱２の内周面との間隙１７に流れ込んだ流体（水等）は、Ｏリング１８によってシールされて下流側へ通り抜けることができない。したがって、流体が全閉状態の弁体６の上流側から上記間隙１７を流れて弁体６の下流側へ漏出するといった不具合を防止することができる。
【００１１】
また、弁箱２内の流体は、上記間隙１７にも流れ込むため、流体の圧力は弁箱シート７の内周面と外周面とに作用して互いに打ち消し合う。これにより、弁箱シート７が流体の圧力によって径方向に撓む（変形する）といった不具合を防止することができる。したがって、弁体６を全閉した際の止水性能が十分に確保される。
【００１２】
さらに、弁箱シート７は、弁箱２と一体ではなく、別体であるため、水圧や地盤の変動によって弁箱２に力が作用し、弁箱２が変形する場合であっても、Ｏリング１８が拡縮して弁箱２の変形を吸収し、弁箱シート７は変形を起こさずに弁体６との整合性を維持して水密に摺接する。したがって、漏水が生じることはなく、弁箱シート７の変形によって弁体６が拘束されることもない。
【００１３】
尚、上記バタフライ弁１を組み立てる際、弁箱側軸封シール材１２の装着は以下のようにして行われる。
先ず、図１７に示すように、両シール片１８ａ，１８ｂを取付用溝１９に嵌め込んで弁箱２の内周面にセットした後、弁箱シート７を弁箱２内に挿入し、貫通孔９の位置をボス部８のボス孔部８ａの位置に一致させる。この際、シール片１８ａ，１８ｂの各端部Ａは上記取付用溝１９からボス孔部８ａ内に僅かに突出している。
【００１４】
次に、弁箱側軸封シール材１２を弁箱シート７の内部から貫通孔９とボス孔部８ａとに挿入する。これにより、図１５に示すように、上記シール片１８ａ，１８ｂの各端部Ａが弁箱側軸封シール材１２の外周面に食い込んで圧接する。その後、軸受部材１０を外側からボス部８のボス孔部８ａへ挿入する。
【００１５】
そして、弁棒５と弁体６と弁体側軸封シール材１３とを組み込み、ストッパー２０を取付けて弁箱シート７を固定した後、押え板１５を締付ボルト１６でボス部８に装着する。
【００１６】
このようにしてバタフライ弁１を組み立てた際、上記押え板１５を締付ボルト１６で締め付けることにより、軸受部材１０を介して弁箱側軸封シール材１２が弁体側軸封シール材１３へ押圧され、双方の軸封シール材１２，１３が相互に水密に摺接するとともに、弁箱側軸封シール材１２の外周面が弁箱シート７の貫通孔９の周縁とボス孔部８ａの内周面とに圧接してシール性能が発揮される。
【００１７】
また、弁体６の回転時には、弁体側軸封シール材１３が弁箱側軸封シール材１２に対して水密に摺接しながら回転する。これにより、弁箱シート７の内部流路を流れる流体が弁棒５の周囲において漏水することはない。
【００１８】
さらに、上記のようにシール片１８ａ，１８ｂの各端部Ａが弁箱側軸封シール材１２の外周面に食い込んで圧接しているため、上記シール片１８ａ，１８ｂの端部Ａと弁箱側軸封シール材１２の外周面との間の止水性が十分に確保される。
【００１９】
尚、弁箱側軸封シール材１２の内周面と弁棒５の外周面との間には、微小な隙間が形成され、これにより、弁棒５の回転操作力を低減している。また、軸受部材１０の内周面と弁棒５の外周面との間からの漏れはＯリング２２によって防止されている。
【００２０】
【発明が解決しようとする課題】
しかしながら上記の従来形式では、図１７に示すように、シール片１８ａ，１８ｂの各端部Ａが取付用溝１９からボス孔部８ａ内に突出しているため、弁箱側軸封シール材１２をボス孔部８ａへ挿入する際、ボス孔部８ａ内に突出したシール片１８ａ，１８ｂの各端部Ａが邪魔になり、弁箱側軸封シール材１２の装着に苦労するといった問題がある。
【００２１】
また、シール片１８ａ，１８ｂの端部Ａのボス孔部８ａへの突出量が僅かに狂った場合、シール片１８ａ，１８ｂの端部Ａの弁箱側軸封シール材１２への押し付け力が変化してしまうため、シール片１８ａ，１８ｂの端部Ａと弁箱側軸封シール材１２の外周面との間の止水性が不安定になる恐れがあった。
【００２２】
本発明は、組立て時、弁箱側軸封シール材の装着が容易に行うことができるとともに、十分な止水性が安定して確保されるメタルシートバタフライ弁を提供することを目的とする。
【００２３】
【課題を解決するための手段】
上記目的を達成するために本第１発明は、弁箱内に金属材からなる円筒状の弁箱シートが流路軸心と同心状に配置され、弁箱のボス部および弁箱シートの貫通孔に挿通されて弁棒が配置され、上記弁箱シート内に、弁体が弁棒の軸心廻りに回転自在に設けられ、上記弁体の周縁部に、弁箱シートの内周面に水密に摺接する金属材からなる弁体シートが設けられたメタルシートバタフライ弁であって、上記ボス部に弁棒を回転自在に保持する筒状の軸受部材が挿入され、上記弁箱シートの貫通孔に、弁棒と弁箱シートとの間をシールする弾性材からなるリング状の弁箱側軸封シール材が嵌め込まれ、上記弁箱側軸封シール材に、外周面と上記軸受部材側に対向する外端面とに開放された一対の溝部が形成され、上記弁箱側軸封シール材と弁体との間にリング状の弁体側軸封シール材が設けられ、上記ボス部に、軸受部材を介して弁箱側軸封シール材を弁体側軸封シール材へ押圧する締付手段が設けられ、上記弁箱の内周面と弁箱シートの外周面との間に、弁箱と弁箱シートとの間隙を流路の上流側と下流側とにシールする円環状の弁箱シール材が設けられ、上記弁箱シール材は半円状の一対のシール片に２分割されており、上記両シール片の各端部は、ボス部内に突出して、上記弁箱側軸封シール材の溝部に挿入され、両シール片の各端部を軸受部材側から弁箱側軸封シール材に押圧する押圧部材が上記溝部内に差し込まれているものである。
【００２４】
これによると、バタフライ弁を組み立てる際、弁箱側軸封シール材の装着は以下のようにして行われる。
先ず、一対の両シール片を弁箱の内周面にセットするとともに、弁箱シートを弁箱の内部に挿入し、弁箱シートの貫通孔の位置をボス部の孔部の位置に一致させる。これにより、上記両シール片は弁箱の内周面と弁箱シートの外周面との間隙を流路の上流側と下流側とにシールし、両シール片の各端部はボス部内に突出している。
【００２５】
次に、弁箱側軸封シール材を弁箱シートの内部から貫通孔とボス部内とに挿入する。この際、上記突出しているシール片の端部を弁箱側軸封シール材の外端面から溝部内に挿入する。これにより、従来のようにボス部内に突出したシール片の端部が邪魔になることはなく、弁箱側軸封シール材を容易に弁箱シートの貫通孔とボス部内とに挿入することができ、弁箱側軸封シール材の装着に苦労するといった問題は解決される。
【００２６】
その後、押圧部材をボス部の外側から弁箱側軸封シール材の溝部内に差し込むとともに、軸受部材をボス部内に挿入する。さらに、弁棒と弁体と弁体側軸封シール材とを組み込んだ後、締付手段により、軸受部材を介して弁箱側軸封シール材を弁体側軸封シール材へ押圧する。
【００２７】
これにより、軸受部材を介して弁箱側軸封シール材が弁体側軸封シール材へ押圧され、双方の軸封シール材が相互に水密に摺接するとともに、弁箱側軸封シール材の外周面が弁箱シートの貫通孔の周縁とボス部の孔部の内周面とに圧接してシール性能が発揮される。
【００２８】
また、弁体の回転時には、弁体側軸封シール材が弁箱側軸封シール材に対して水密に摺接しながら回転する。これにより、弁箱シートの内部流路を流れる流体が弁棒の周囲において漏水することはない。
【００２９】
さらに、上記のように締付手段によって軸受部材が弁箱側軸封シール材を弁体側軸封シール材へ押圧する際、押圧部材が上記軸受部材によって溝部内を弁箱側軸封シール材の内端面に向けて押し込まれ、溝部内に挿入されたシール片の端部が上記押圧部材によって弁箱側軸封シール材に押圧される。これにより、上記シール片の端部と弁箱側軸封シール材との間の止水性が安定して十分に確保される。
【００３０】
また、本第２発明は、弁箱内に金属材からなる円筒状の弁箱シートが流路軸心と同心状に配置され、弁箱のボス部および弁箱シートの貫通孔に挿通されて弁棒が配置され、上記弁箱シート内に、弁体が弁棒の軸心廻りに回転自在に設けられ、上記弁体の周縁部に、弁箱シートの内周面に水密に摺接する金属材からなる弁体シートが設けられたメタルシートバタフライ弁であって、上記ボス部に弁棒を回転自在に保持する筒状の軸受部材が挿入され、上記弁箱シートの貫通孔に、弁棒と弁箱シートとの間をシールする弾性材からなるリング状の弁箱側軸封シール材が嵌め込まれ、上記弁箱側軸封シール材と弁体との間にリング状の弁体側軸封シール材が設けられ、上記ボス部に、軸受部材を介して弁箱側軸封シール材を弁体側軸封シール材へ押圧する締付手段が設けられ、上記弁箱の内周面と弁箱シートの外周面との間に、弁箱と弁箱シートとの間隙を流路の上流側と下流側とにシールする円環状の弁箱シール材が設けられ、上記弁箱シール材は半円状の一対のシール片に２分割されており、上記両シール片の各端部が上記弁箱側軸封シール材の外周面に一体に形成されているものである。
【００３１】
これによると、バタフライ弁を組み立てる際、弁箱側軸封シール材の装着は以下のようにして行われる。
両シール片と弁箱側軸封シール材とは一体物であるため、先ず、弁箱側軸封シール材を弁箱内からボス部内に挿入するとともに、一対の両シール片を弁箱の内周面にセットする。その後、弁箱シートを弁箱の内部に挿入し、弁箱シートの貫通孔の位置をボス部の孔部の位置に一致させ、上記弁箱側軸封シール材を上記貫通孔に嵌め込む。
【００３２】
このように、両シール片と弁箱側軸封シール材とを別体ではなく一体物にしたことにより、弁箱側軸封シール材を容易に弁箱シートの貫通孔とボス部内とに嵌め込むことができ、弁箱側軸封シール材の装着に苦労するといった問題は解決される。
【００３３】
また、上記両シール片は弁箱の内周面と弁箱シートの外周面との間隙を流路の上流側と下流側とにシールする。その後、軸受部材をボス部内に挿入し、さらに、弁棒と弁体と弁体側軸封シール材とを組み込んだ後、締付手段により、軸受部材を介して弁箱側軸封シール材を弁体側軸封シール材へ押圧する。
【００３４】
これにより、軸受部材を介して弁箱側軸封シール材が弁体側軸封シール材へ押圧され、双方の軸封シール材が相互に水密に摺接するとともに、弁箱側軸封シール材の外周面が弁箱シートの貫通孔の周縁とボス部の孔部の内周面とに圧接してシール性能が発揮される。
【００３５】
また、弁体の回転時には、弁体側軸封シール材が弁箱側軸封シール材に対して水密に摺接しながら回転する。これにより、弁箱シートの内部流路を流れる流体が弁棒の周囲において漏水することはない。
【００３６】
さらに、シール片と弁箱側軸封シール材とを一体物に形成したことにより、上記シール片の端部と弁箱側軸封シール材との間の止水性が安定して十分に確保される。
【００３７】
【発明の実施の形態】
以下、本発明における第１の実施の形態を図１〜図６に基づいて説明する。尚、従来と同一の部材については同じ符号を付記して説明を省略する。
【００３８】
図１（ｂ）に示すように、弁箱側軸封シール材１２には、外周面と軸受部材１０側に対向する外端面１２ａとに開放された一対の溝部３１が形成されている。これら両溝部３１は、弁棒５の軸心４方向から見て、ほぼ半円状に形成されている。また、図１（ｂ），図４に示すように、溝部３１の内端から弁箱側軸封シール材１２の弁体側軸封シール材１３側に対向する内端面１２ｂまでの距離Ｈは弁箱シート７の厚さに一致し、弁箱側軸封シール材１２を装着した際、図３に示すように、上記溝部３１の内端から弁箱側軸封シール材１２の内端面１２ｂまでの部分（上記距離Ｈで示した部分）が弁箱シート７の貫通孔９に嵌り込む。
【００３９】
図３〜図５に示すように、Ｏリング１８を構成する両シール片１８ａ，１８ｂの各端部Ａはそれぞれ、ボス部８のボス孔部８ａ内に突出して、上記弁箱側軸封シール材１２の溝部３１に挿入されている。
【００４０】
また、軸受部材１０の弁箱側軸封シール材１２側に対向する内端面には、上記両シール片１８ａ，１８ｂの各端部Ａを弁箱側軸封シール材１２に押圧する一対の押圧部材３２が設けられている。図１（ａ）に示すように、これら両押圧部材３２は、断面半円形状の棒状突起であり、弁箱側軸封シール材１２の外端面１２ａから両溝部３１に差し込み可能に構成されている。尚、両押圧部材３２の内端部３２ａは四フッ化エチレン樹脂やゴム等の弾性材で形成されている。
【００４１】
以下、上記構成における作用を説明する。
バタフライ弁１を組み立てる際、弁箱側軸封シール材１２の装着は以下のようにして行われる。
【００４２】
図４に示すように、両シール片１８ａ，１８ｂを取付用溝１９に嵌め込んで弁箱２の内周面にセットした後、弁箱シート７を弁箱２内に挿入し、弁箱シート７の貫通孔９の位置をボス部８のボス孔部８ａの位置に一致させる。これにより、上記両シール片１８ａ，１８ｂは弁箱２と弁箱シート７との間隙１７を流路の上流側と下流側とにシールし、両シール片１８ａ，１８ｂの各端部Ａは上記取付用溝１９からボス孔部８ａ内に突出している。
【００４３】
次に、弁箱側軸封シール材１２を弁箱シート７の内部から貫通孔９とボス孔部８ａとに挿入する。この際、上記突出しているシール片１８ａ，１８ｂの端部Ａを弁箱側軸封シール材１２の外端面１２ａから両溝部３１内に挿入する。これにより、従来のようにボス孔部８ａ内に突出したシール片１８ａ，１８ｂの端部Ａが邪魔になることはなく、弁箱側軸封シール材１２を容易に弁箱シート７の貫通孔９とボス部８のボス孔部８ａとに挿入することができ、弁箱側軸封シール材１２の装着に苦労するといった問題は解決される。尚、この際、弁箱側軸封シール材１２の溝部３１の内端から内端面１２ｂまでの部分が弁箱シート７の貫通孔９に嵌り込む。
【００４４】
その後、図５の実線で示すように、軸受部材１０を外側からボス部８のボス孔部８ａに挿入し、この際、両押圧部材３２を弁箱側軸封シール材１２の両溝部３１内に差し込む。さらに、図６に示すように、弁棒５と弁体６と弁体側軸封シール材１３とを組み込み、ストッパー２０を取付けて弁箱シート７を固定した後、押え板１５を締付ボルト１６でボス部８に装着する。
【００４５】
このようにしてバタフライ弁１を組み立てた際、図６に示すように、上記押え板１５を締付ボルト１６で締め付けることにより、軸受部材１０を介して弁箱側軸封シール材１２が弁体側軸封シール材１３へ押圧され、双方の軸封シール材１２，１３が相互に水密に摺接するとともに、弁箱側軸封シール材１２の外周面が弁箱シート７の貫通孔９の周縁とボス部８のボス孔部８ａの内周面とに圧接してシール性能が発揮される。
【００４６】
また、弁体６の回転時には、弁体側軸封シール材１３が弁箱側軸封シール材１２に対して水密に摺接しながら回転する。これにより、弁箱シート７の内部流路を流れる流体が弁棒５の周囲において漏水することはない。
【００４７】
さらに、上記のように押え板１５を締付ボルト１６で締め付けることによって、軸受部材１０が弁箱側軸封シール材１２を弁体側軸封シール材１３へ押圧する際、両押圧部材３２が両溝部３１内を弁箱側軸封シール材１２の内端面１２ｂに向けて押し込まれ、両溝部３１内に挿入された両シール片１８ａ，１８ｂの各端部Ａが上記両押圧部材３２によって弁箱側軸封シール材１２に押圧される。これにより、両シール片１８ａ，１８ｂの端部Ａのボス孔部８ａ内への突出量が僅かに狂っていても、上記シール片１８ａ，１８ｂの端部Ａと弁箱側軸封シール材１２との間の止水性が安定して十分に確保される。
【００４８】
尚、押圧部材３２の内端部３２ａは弾性材で形成されているため、上記内端部３２ａが上記ボス孔部８ａの内周面に圧接して、この部分のシールも確実に行える。
【００４９】
上記第１の実施の形態では、図１に示すように、押圧部材３２を軸受部材１０に一体に設けたが、押圧部材３２を軸受部材１０から個別に分離してもよい。また、図７に示すように、押圧部材３２をシール片１８ａ，１８ｂの各端部に一体的に形成してもよい。
【００５０】
次に第２の実施の形態を図８〜図１０に基づいて説明する。
弁箱側軸封シール材１２は、軸受部材１０に圧接するリング状の主シール部４０と、弁体側軸封シール材１３に圧接するリング状の副シール部４１とに分割されて構成されている。尚、上記副シール部４１の厚さは弁箱シート７の厚さに一致している。
【００５１】
また、両シール片１８ａ，１８ｂの一端部はそれぞれ一方の弁箱側軸封シール材１２の主シール部４０の外周面に一体に形成され、両シール片１８ａ，１８ｂの他端部はそれぞれ他方の弁箱側軸封シール材１２の主シール部４０の外周面に一体に形成されている。尚、シール片１８ａ，１８ｂの端部の内周縁は主シール部４０の内端面（すなわち副シール部４１に対向する面）と面一になっている。
【００５２】
以下、上記構成における作用を説明する。
バタフライ弁１を組み立てる際、弁箱側軸封シール材１２の装着は以下のようにして行われる。
【００５３】
両シール片１８ａ，１８ｂと両弁箱側軸封シール材１２の主シール部４０とは一体物であるため、先ず、図１０（ａ）に示すように、上記主シール部４０を弁箱２内からボス部８のボス孔部８ａ内にそれぞれ挿入するとともに、両シール片１８ａ，１８ｂを取付用溝１９に嵌め込んで弁箱２の内周面にセットする。その後、図１０（ｂ）に示すように、弁箱シート７を弁箱２内に挿入し、弁箱シート７の貫通孔９の位置をボス部８のボス孔部８ａの位置に一致させ、次に、図１０（ｃ）に示すように、両弁箱側軸封シール材１２の副シール部４１を弁箱シート７内から上記貫通孔９に嵌め込む。
【００５４】
このように、両シール片１８ａ，１８ｂと弁箱側軸封シール材１２の主シール部４０とを別体ではなく一体物にしたことにより、上記主シール部４０を容易にボス部８のボス孔部８ａに嵌め込むことができる。さらに、その後、副シール部４１を弁箱シート７内から貫通孔９に嵌め込むことにより、上記主シール部４０と副シール部４１とで弁箱側軸封シール材１２が構成されるため、弁箱側軸封シール材１２の装着に苦労するといった問題は解決される。
【００５５】
また、上記両シール片１８ａ，１８ｂは弁箱２と弁箱シート７との間隙１７を流路の上流側と下流側とにシールする。その後、図９に示すように、軸受部材１０をボス部８のボス孔部８ａに挿入し、さらに、弁棒５と弁体６と弁体側軸封シール材１３とを組み込み、ストッパー２０を取付けて弁箱シート７を固定した後、押え板１５を締付ボルト１６でボス部８に装着する。
【００５６】
このようにしてバタフライ弁１を組み立てた際、上記押え板１５を締付ボルト１６で締め付けることにより、軸受部材１０を介して弁箱側軸封シール材１２が弁体側軸封シール材１３へ押圧されるため、主シール部４０と副シール部４１とが互いに圧接して両シール部４０，４１間がシールされるとともに、上記副シール部４１と弁体側軸封シール材１３とが相互に水密に摺接し、上記副シール部４１の外周面が弁箱シート７の貫通孔９の周縁に圧接してシール性能が発揮されるとともに、上記主シール部４０の外周面がボス部８のボス孔部８ａの内周面に圧接してシール性能が発揮される。
【００５７】
また、弁体６の回転時には、弁体側軸封シール材１３が弁箱側軸封シール材１２に対して水密に摺接しながら回転する。これにより、弁箱シート７の内部流路を流れる流体が弁棒５の周囲において漏水することはない。
【００５８】
さらに、両シール片１８ａ，１８ｂと弁箱側軸封シール材１２の主シール部４０とを一体物に形成したことにより、上記両シール片１８ａ，１８ｂの端部と主シール部４０との間の止水性が安定して十分に確保される。
【００５９】
上記第２の実施の形態では、図８に示すように、弁箱側軸封シール材１２を主シール部４０と副シール部４１とに分割したが、このような分割構造でなくてもよい。すなわち、第３の実施の形態として、図１１に示すように、両シール片１８ａ，１８ｂの一端部はそれぞれ一方の弁箱側軸封シール材１２の外周面に一体に形成され、両シール片１８ａ，１８ｂの他端部はそれぞれ他方の弁箱側軸封シール材１２の外周面に一体に形成されている。尚、シール片１８ａ，１８ｂの端部の内周縁から弁箱側軸封シール材１２の内端面１２ｂまでの距離Ｈは弁箱シート７の厚さに一致している。
【００６０】
以下、上記構成における作用を説明する。
バタフライ弁１を組み立てる際、弁箱側軸封シール材１２の装着は以下のようにして行われる。
【００６１】
両シール片１８ａ，１８ｂと両弁箱側軸封シール材１２とは一体物であるため、先ず、図１１（ａ）の実線で示すように、弁箱側軸封シール材１２を弁箱２内からボス部８のボス孔部８ａ内にそれぞれ挿入するとともに、両シール片１８ａ，１８ｂを取付用溝１９に嵌め込んで弁箱２の内周面にセットする。
【００６２】
その後、弁箱シート７を弁箱２内に挿入する。この際、図１１（ａ）の仮想線で示すように、両弁箱側軸封シール材１２の内端面１２ｂが弁箱シート７よりも外側へ位置するように、両弁箱側軸封シール材１２を外側へ寄せておく（尚、この時、シール片１８ａ，１８ｂは弾性体であるため僅かに伸長する）。このようにして弁箱シート７を弁箱２内に挿入した後、図１１（ｂ）で示すように、弁箱シート７の貫通孔９の位置をボス部８のボス孔部８ａの位置に一致させ、弁箱側軸封シール材１２の内端部を上記貫通孔９に嵌め込む（尚、この時、シール片１８ａ，１８ｂが元の長さに縮む）。
【００６３】
このように、両シール片１８ａ，１８ｂと弁箱側軸封シール材１２とを別体ではなく一体物にしたことにより、弁箱側軸封シール材１２を容易に弁箱シート７の貫通孔９とボス部８のボス孔部８ａとに嵌め込むことができ、弁箱側軸封シール材１２の装着に苦労するといった問題は解決される。
【００６４】
その後、軸受部材１０を外側からボス孔部８ａ内に挿入し、さらに、弁棒５と弁体６と弁体側軸封シール材１３とを組み込み、ストッパー２０を取付けて弁箱シート７を固定した後、押え板１５を締付ボルト１６でボス部８に装着する。
【００６５】
このようにしてバタフライ弁１を組み立てた際、上記押え板１５を締付ボルト１６で締め付けることにより、軸受部材１０を介して弁箱側軸封シール材１２が弁体側軸封シール材１３へ押圧されるため、双方の軸封シール材１２，１３が相互に水密に摺接するとともに、弁箱側軸封シール材１２の外周面が弁箱シート７の貫通孔９の周縁とボス部８のボス孔部８ａの内周面とに圧接してシール性能が発揮される。
【００６６】
また、弁体６の回転時には、弁体側軸封シール材１３が弁箱側軸封シール材１２に対して水密に摺接しながら回転する。これにより、弁箱シート７の内部流路を流れる流体が弁棒５の周囲において漏水することはない。
【００６７】
さらに、シール片１８ａ，１８ｂと弁箱側軸封シール材１２とを一体物に形成したことにより、上記シール片１８ａ，１８ｂの端部と弁箱側軸封シール材１２との間の止水性が安定して十分に確保される。
【００６８】
【発明の効果】
以上のように、本発明によれば、組立て時、弁箱側軸封シール材の装着が容易に行うことができ、さらに、シール片の端部と弁箱側軸封シール材との間の止水性を安定して十分に確保することができる。
【図面の簡単な説明】
【図１】本発明の第１の実施の形態におけるバタフライ弁の軸受部材と弁箱側軸封シール材との斜視図であり、（ａ）が軸受部材、（ｂ）が弁箱側軸封シール材を示す。
【図２】同、バタフライ弁の軸受部材と弁箱側軸封シール材とシール片とを組み合わせた斜視図である。
【図３】同、バタフライ弁の軸受部材と弁箱側軸封シール材とシール片と弁箱シートとを組み合わせた断面図である。
【図４】同、バタフライ弁の弁箱側軸封シール材の装着手順を示す断面図である。
【図５】同、バタフライ弁の弁箱側軸封シール材の装着手順を示す断面図である。
【図６】同、バタフライ弁の軸封部分の断面図である。
【図７】同、他の実施の形態におけるバタフライ弁の軸受部材と弁箱側軸封シール材とシール片と弁箱シートとを組み合わせた断面図である。
【図８】本発明の第２の実施の形態におけるバタフライ弁のＯリングと弁箱側軸封シール材との図である。
【図９】同、バタフライ弁の軸受部材と弁箱側軸封シール材とシール片と弁箱シートとを組み合わせた断面図である。
【図１０】同、バタフライ弁の弁箱側軸封シール材の装着手順を示す断面図であり、（ａ）はシール片と弁箱側軸封シール材の主シール部とを装着した状態を示し、（ｂ）は弁箱シートを装着した状態を示し、（ｃ）は弁箱側軸封シール材の副シール部を装着した状態を示す。
【図１１】本発明の第３の実施の形態におけるバタフライ弁の弁箱側軸封シール材の装着手順を示す断面図であり、（ａ）はシール片と弁箱側軸封シール材とを装着した状態を示し、（ｂ）は弁箱シートを装着した状態を示す。
【図１２】従来のバタフライ弁の正面から見た縦断面図である。
【図１３】同、バタフライ弁の側面から見た縦断面図である。
【図１４】同、バタフライ弁の弁棒軸心から見た横断面図である。
【図１５】同、バタフライ弁の軸封部分の断面図である。
【図１６】同、バタフライ弁の弁箱シートの貫通孔に弁箱側軸封シール材を嵌め込んだ状態の斜視図である。
【図１７】同、バタフライ弁の弁箱側軸封シール材の装着手順を示す断面図である。
【符号の説明】
１ バタフライ弁
２ 弁箱
３ 流路軸心
４ 軸心
５ 弁棒
６ 弁体
７ 弁箱シート
８ ボス部
９ 貫通孔
１０ 軸受部材
１１ 弁体シート
１２ 弁箱側軸封シール材
１３ 弁体側軸封シール材
１４ 締付手段
１７ 間隙
１８ Ｏリング（弁箱シール材）
１８ａ，１８ｂ シール片
３１ 溝部
３２ 押圧部材
Ａ 端部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a metal sheet butterfly valve including a valve box sheet and a valve body sheet made of a metal material.
[0002]
[Prior art]
Conventionally, as this type of metal sheet butterfly valve, there is, for example, one shown in FIGS. That is, as shown in FIGS. 12 to 14, the metal sheet butterfly valve 1 includes a valve box 2 and a pair of rotatable shafts 4 that are rotatable about an axis 4 orthogonal to a flow path axis 3 of the valve box 2. It comprises a valve stem 5 and a valve element 6 provided on the valve stem 5.
[0003]
Inside the valve case 2, a valve case sheet 7 made of a cylindrical thin metal material is arranged concentrically with the flow path axis 3. Further, a pair of bosses 8 are formed in the valve box 2, and both bosses 8 are formed with boss holes 8 a (see FIG. 17) that open on the inner and outer surfaces of the valve box 2. As shown in FIGS. 15 to 17, each of the valve stems 5 is inserted into a boss hole 8 a of the boss 8 and a pair of through holes 9 formed in the valve box sheet 7. Is rotatably held by a cylindrical bearing member 10 (bushing) inserted into the housing.
[0004]
The valve body 6 is connected between the pair of valve rods 5 by a plurality of pins (not shown), and a peripheral portion of the valve body 6 is made of a metal material that comes into sliding contact with the inner peripheral surface of the valve box sheet 7 in a watertight manner. Is provided. As shown by the solid line in FIG. 14, in a state where the valve body 6 is fully closed, the valve body sheet 11 is arranged so as to prevent the seizure of the valve body sheet 7 with the flow axis of the valve body 6. 3 and is inclined in the opening direction by a small angle α (for example, α = about 3 °) with respect to a section including the axis 4.
[0005]
As shown in FIGS. 12 and 15, a pair of ring-shaped shaft seal members 12 and 13 are disposed between the valve body 6 and the inner ends of the bearing members 10, respectively. Of these, as shown in FIGS. 15 to 17, the inner end of the valve box-side shaft sealing material 12 arranged on the bearing member 10 side (outside) is inserted into the through hole 9 of the valve box sheet 7, The space between the valve stem 5 and the valve box sheet 7 is sealed. In addition, the valve box-side shaft sealing material 12 includes a core metal inside an elastic material such as rubber (CR), and a contact surface (inner end surface) that contacts the valve body-side shaft sealing material 13 is coated with a fluororesin. Things. Further, the valve body-side shaft seal 13 disposed on the valve body 6 side (that is, between the valve body 6 and the valve box-side shaft seal 12) is made of a metal material.
[0006]
Each of the boss portions 8 is provided with a fastening means 14 for pressing the valve box-side shaft sealing material 12 against the valve body-side shaft sealing material 13 via the bearing member 10. These fastening means 14 include an annular pressing plate 15 arranged at the outer end of the bearing member 10, and a plurality of tightening means for attaching the pressing plate 15 to the boss portion 8 and tightening the pressing plate 15 to the valve body-side shaft sealing material 13. And an attached bolt 16.
[0007]
As shown in FIGS. 13 to 16, a gap 17 between the inner peripheral surface of the valve box 2 and the valve box sheet 7 is provided between the valve box 2 and the outer peripheral surface of the valve box sheet 7. An annular O-ring 18 (valve box sealing material) is provided for sealing on the upstream side and the downstream side. As shown by the solid line in FIG. 14, the O-ring 18 is formed of an elastic body, and substantially faces the valve body sheet 11 of the fully closed valve body 6 via the valve box sheet 7.
[0008]
As shown in FIG. 16, the O-ring 18 is divided into a pair of semicircular seal pieces 18a and 18b, and these seal pieces 18a and 18b are formed on the inner periphery of the valve box 2 as shown in FIG. It is fitted in a mounting groove 19 formed on the surface. As shown by the solid line in FIG. 16, each end of the two seal pieces 18 a and 18 b bites into the outer peripheral surface of the valve box-side shaft seal material 12 and is in pressure contact therewith.
[0009]
As shown in FIGS. 13 and 14, a ring-shaped stopper 20 for fixing the valve box sheet 7 in the direction of the flow axis 3 is provided in the valve box 2 with the upstream end of the valve box sheet 7. It is arranged adjacent to the downstream end and is attached to the valve box 2 by bolts 21 (see FIG. 14).
[0010]
According to this, as shown by the solid line in FIG. 14, when the valve element 6 is fully closed, the valve element sheet 11 comes into sliding contact with the inner peripheral surface of the valve box sheet 7 in a watertight manner. At this time, the fluid (water or the like) flowing into the gap 17 between the outer peripheral surface of the valve box sheet 7 and the inner peripheral surface of the valve box 2 from the upstream side of the flow path in the valve box 2 is sealed by the O-ring 18. Cannot pass downstream. Therefore, it is possible to prevent a problem that the fluid flows from the upstream side of the valve body 6 in the fully closed state through the gap 17 and leaks to the downstream side of the valve body 6.
[0011]
Further, since the fluid in the valve box 2 also flows into the gap 17, the pressure of the fluid acts on the inner and outer peripheral surfaces of the valve box sheet 7 to cancel each other. Thereby, it is possible to prevent a problem that the valve box sheet 7 bends (deforms) in the radial direction due to the pressure of the fluid. Therefore, the water stopping performance when the valve body 6 is fully closed is sufficiently ensured.
[0012]
Further, since the valve box sheet 7 is not integral with the valve box 2 but is separate from the valve box 2, even if a force acts on the valve box 2 due to a change in water pressure or ground, the valve box 2 is deformed. The ring 18 expands and contracts to absorb the deformation of the valve box 2, and the valve box sheet 7 slides in a watertight manner while maintaining the consistency with the valve body 6 without deformation. Therefore, no water leakage occurs, and the valve body 6 is not restrained by the deformation of the valve box sheet 7.
[0013]
At the time of assembling the butterfly valve 1, the valve box-side shaft seal member 12 is mounted as follows.
First, as shown in FIG. 17, the two seal pieces 18a and 18b are fitted into the mounting grooves 19 and set on the inner peripheral surface of the valve box 2, and then the valve box sheet 7 is inserted into the valve box 2 and penetrated. The position of the hole 9 is matched with the position of the boss hole 8 a of the boss 8. At this time, each end A of the seal pieces 18a and 18b slightly protrudes from the mounting groove 19 into the boss hole 8a.
[0014]
Next, the valve box-side shaft sealing material 12 is inserted from the inside of the valve box sheet 7 into the through hole 9 and the boss hole 8a. As a result, as shown in FIG. 15, each end A of the seal pieces 18a and 18b bites into the outer peripheral surface of the valve box-side shaft seal material 12 and comes into pressure contact therewith. Thereafter, the bearing member 10 is inserted into the boss hole 8a of the boss 8 from outside.
[0015]
After the valve rod 5, the valve element 6, and the valve element-side shaft sealing material 13 are assembled, the stopper 20 is attached to fix the valve box sheet 7, and then the holding plate 15 is attached to the boss 8 with the tightening bolts 16. .
[0016]
When the butterfly valve 1 is assembled in this manner, the valve plate-side shaft seal 12 is pressed against the valve body shaft seal 13 via the bearing member 10 by tightening the holding plate 15 with the tightening bolt 16. The two shaft seal members 12 and 13 are in sliding contact with each other in a water-tight manner, and the outer peripheral surface of the valve box side shaft seal member 12 is formed around the periphery of the through hole 9 of the valve box sheet 7 and the inner periphery of the boss hole 8a. The sealing performance is exhibited by pressing against the surface.
[0017]
When the valve element 6 rotates, the valve element-side shaft sealing material 13 rotates while sliding on the valve box-side shaft sealing material 12 in a watertight manner. Thereby, the fluid flowing through the internal flow path of the valve box sheet 7 does not leak around the valve stem 5.
[0018]
Further, since the ends A of the seal pieces 18a and 18b bite into the outer peripheral surface of the valve box-side shaft seal member 12 and are pressed against each other as described above, the end A of the seal pieces 18a and 18b and the valve box Water stoppage between the side shaft sealing material 12 and the outer peripheral surface is sufficiently ensured.
[0019]
A small gap is formed between the inner peripheral surface of the valve box-side shaft sealing material 12 and the outer peripheral surface of the valve stem 5, thereby reducing the rotational operation force of the valve stem 5. Further, leakage from between the inner peripheral surface of the bearing member 10 and the outer peripheral surface of the valve stem 5 is prevented by the O-ring 22.
[0020]
[Problems to be solved by the invention]
However, in the above-mentioned conventional type, as shown in FIG. 17, since each end A of the sealing pieces 18a and 18b protrudes from the mounting groove 19 into the boss hole 8a, the valve box-side shaft sealing material 12 is not provided. At the time of insertion into the boss hole 8a, there is a problem that each end A of the sealing pieces 18a and 18b protruding into the boss hole 8a becomes a hindrance, and it is difficult to mount the valve box-side shaft sealing material 12.
[0021]
Further, when the amount of protrusion of the end portions A of the seal pieces 18a, 18b into the boss hole 8a is slightly changed, the pressing force of the end portions A of the seal pieces 18a, 18b against the valve box-side shaft seal material 12 is reduced. Therefore, there is a possibility that the water stopping property between the end portions A of the seal pieces 18a and 18b and the outer peripheral surface of the valve box-side shaft seal material 12 may become unstable.
[0022]
SUMMARY OF THE INVENTION An object of the present invention is to provide a metal sheet butterfly valve in which a valve box-side shaft sealing material can be easily mounted at the time of assembly, and sufficient water stoppage is stably ensured.
[0023]
[Means for Solving the Problems]
In order to achieve the above object, the first aspect of the present invention is directed to a first aspect of the present invention, wherein a cylindrical valve box sheet made of a metal material is disposed concentrically with a flow path axis, and a boss portion of the valve box and a penetration of the valve box sheet. A valve stem is inserted through the hole, and a valve element is provided in the valve box sheet so as to be rotatable around the axis of the valve rod, and on the peripheral edge of the valve element, on the inner peripheral surface of the valve box sheet. A metal sheet butterfly valve provided with a valve body sheet made of a metal material that slides in a watertight manner, wherein a cylindrical bearing member that rotatably holds a valve rod is inserted into the boss portion, and the valve box sheet penetrates. A ring-shaped valve box-side shaft sealing seal made of an elastic material for sealing between the valve rod and the valve box sheet is fitted into the hole, and the outer peripheral surface and the bearing member side are inserted into the valve box-side shaft sealing seal. A pair of open grooves is formed on the outer end face facing the valve body, and the valve box side shaft seal material and the valve body are formed. A ring-shaped valve body-side shaft seal material is provided therebetween, and the boss portion is provided with a tightening means for pressing the valve box-side shaft seal material to the valve body-side shaft seal material via a bearing member. An annular valve box sealing material is provided between the inner peripheral surface of the valve box and the outer peripheral surface of the valve box sheet to seal the gap between the valve box and the valve box sheet on the upstream side and the downstream side of the flow path. The valve box sealing material is divided into a pair of semicircular sealing pieces, and each end of the both sealing pieces protrudes into the boss portion and is inserted into the groove of the valve box side shaft sealing material. A pressing member for pressing each end of both seal pieces from the bearing member side to the valve box-side shaft sealing material is inserted into the groove.
[0024]
According to this, when assembling the butterfly valve, the mounting of the valve box side shaft sealing material is performed as follows.
First, a pair of both seal pieces are set on the inner peripheral surface of the valve box, and the valve box sheet is inserted into the valve box so that the position of the through hole of the valve box sheet matches the position of the hole of the boss. . Thereby, the two seal pieces seal the gap between the inner peripheral surface of the valve box and the outer peripheral surface of the valve box sheet on the upstream side and the downstream side of the flow path, and each end of both seal pieces protrudes into the boss portion. ing.
[0025]
Next, the valve box-side shaft sealing material is inserted into the through hole and the boss from inside the valve box sheet. At this time, the end of the protruding seal piece is inserted into the groove from the outer end surface of the valve box-side shaft seal material. Thus, the end of the seal piece protruding into the boss portion does not become an obstacle as in the related art, and the valve box side shaft seal material can be easily inserted into the through hole of the valve box sheet and the boss portion. This solves the problem of difficulty in mounting the valve box-side shaft sealing material.
[0026]
Thereafter, the pressing member is inserted into the groove of the valve box-side shaft sealing material from the outside of the boss, and the bearing member is inserted into the boss. Further, after the valve stem, the valve element, and the valve element-side shaft sealing seal material are assembled, the valve box-side shaft sealing material is pressed against the valve body-side shaft sealing seal material via a bearing member by a fastening means.
[0027]
As a result, the valve-box-side shaft-sealing material is pressed against the valve-body-side shaft-sealing material via the bearing member, and the two shaft-sealing materials come into sliding contact with each other in a watertight manner. The surface comes into pressure contact with the peripheral edge of the through hole of the valve box sheet and the inner peripheral surface of the hole of the boss portion, thereby exhibiting sealing performance.
[0028]
Further, when the valve element rotates, the valve element-side shaft sealing seal member rotates while being in water-tight sliding contact with the valve box-side shaft sealing seal member. Thereby, the fluid flowing through the internal flow path of the valve box sheet does not leak around the valve stem.
[0029]
Further, as described above, when the bearing member presses the valve box side shaft sealing seal material against the valve body side shaft sealing seal material by the tightening means, the pressing member moves the inside of the groove by the bearing member into the valve box side shaft sealing seal material. The end of the seal piece pushed into the inner end face and inserted into the groove is pressed against the valve box-side shaft seal material by the pressing member. Thereby, the water stoppage between the end of the seal piece and the valve box-side shaft sealing material is stably and sufficiently secured.
[0030]
Further, in the second invention, a cylindrical valve box sheet made of a metal material is disposed concentrically with the flow path axis in the valve box, and is inserted into a boss portion of the valve box and a through hole of the valve box sheet. A valve rod is disposed, a valve element is provided in the valve box sheet so as to be rotatable around the axis of the valve rod, and a metal that comes into sliding contact with an inner peripheral surface of the valve box sheet in a peripheral portion of the valve element in a watertight manner. Metal valve butterfly valve provided with a valve body sheet made of a material, wherein a cylindrical bearing member for rotatably holding a valve rod is inserted into the boss portion, and a valve rod is inserted into a through hole of the valve box sheet. A ring-shaped valve box-side shaft sealing material made of an elastic material that seals between the valve body sheet and the valve box sheet is fitted, and a ring-shaped valve body-side shaft sealing material is provided between the valve box-side shaft sealing material and the valve body. A sealing material is provided, and the boss portion presses the valve box-side shaft sealing seal material to the valve body-side shaft sealing seal material via a bearing member. A circle for sealing a gap between the valve box and the valve box sheet between the inner peripheral surface of the valve box and the outer peripheral surface of the valve box sheet on the upstream side and the downstream side of the flow path. An annular valve box sealing material is provided, and the valve box sealing material is divided into a pair of semicircular sealing pieces, and each end of both the sealing pieces is an outer periphery of the valve box side shaft sealing material. It is formed integrally with the surface.
[0031]
According to this, when assembling the butterfly valve, the mounting of the valve box side shaft sealing material is performed as follows.
Since both the seal pieces and the valve box-side shaft seal material are integral with each other, first, the valve box-side shaft seal material is inserted into the boss portion from inside the valve box, and the pair of both seal pieces are inserted into the valve box. Set on the peripheral surface. Thereafter, the valve box sheet is inserted into the valve box, the position of the through hole of the valve box sheet is matched with the position of the hole of the boss, and the valve box side shaft sealing material is fitted into the through hole.
[0032]
As described above, the two seal pieces and the valve box-side shaft seal material are not integrated but are integrated, so that the valve box-side shaft seal material can be easily fitted into the through hole of the valve box sheet and the inside of the boss portion. This solves the problem of difficulty in mounting the valve box-side shaft sealing material.
[0033]
The two seal pieces seal the gap between the inner peripheral surface of the valve box and the outer peripheral surface of the valve box sheet on the upstream side and the downstream side of the flow path. Thereafter, the bearing member is inserted into the boss portion, and further, the valve rod, the valve body, and the valve body-side shaft sealing seal material are assembled. Press against body-side shaft seal.
[0034]
As a result, the valve-box-side shaft-sealing material is pressed against the valve-body-side shaft-sealing material via the bearing member, and the two shaft-sealing materials come into sliding contact with each other in a watertight manner. The surface comes into pressure contact with the peripheral edge of the through hole of the valve box sheet and the inner peripheral surface of the hole of the boss portion, thereby exhibiting sealing performance.
[0035]
Further, when the valve element rotates, the valve element-side shaft sealing seal member rotates while being in water-tight sliding contact with the valve box-side shaft sealing seal member. Thereby, the fluid flowing through the internal flow path of the valve box sheet does not leak around the valve stem.
[0036]
Further, since the seal piece and the valve box-side shaft seal material are formed integrally, the water stopping between the end of the seal piece and the valve box-side shaft seal material is stably and sufficiently secured. You.
[0037]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. The same members as those in the related art are denoted by the same reference numerals, and description thereof will be omitted.
[0038]
As shown in FIG. 1B, a pair of groove portions 31 are formed on the outer peripheral surface and the outer end surface 12 a facing the bearing member 10 side in the valve box-side shaft sealing material 12. The two groove portions 31 are formed in a substantially semicircular shape when viewed from the direction of the axis 4 of the valve stem 5. Further, as shown in FIGS. 1B and 4, the distance H from the inner end of the groove 31 to the inner end surface 12 b of the valve box side shaft sealing material 12 facing the valve body side shaft sealing material 13 is determined by the valve. When the thickness of the box sheet 7 is matched and the valve box side shaft sealing material 12 is attached, as shown in FIG. 3, from the inner end of the groove 31 to the inner end surface 12b of the valve box side shaft sealing material 12. (The portion indicated by the distance H) fits into the through hole 9 of the valve box sheet 7.
[0039]
As shown in FIGS. 3 to 5, each end A of each of the seal pieces 18a and 18b constituting the O-ring 18 protrudes into the boss hole 8a of the boss portion 8, respectively. It is inserted into the groove 31 of the material 12.
[0040]
On the inner end surface of the bearing member 10 facing the valve box-side shaft sealing seal member 12, a pair of pressing portions for pressing the respective end portions A of the two sealing pieces 18 a and 18 b against the valve box-side shaft sealing seal member 12. A member 32 is provided. As shown in FIG. 1A, these pressing members 32 are rod-shaped projections having a semicircular cross section, and are configured to be insertable into the two groove portions 31 from the outer end surface 12 a of the valve box-side shaft sealing material 12. I have. The inner ends 32a of the pressing members 32 are formed of an elastic material such as tetrafluoroethylene resin or rubber.
[0041]
Hereinafter, the operation of the above configuration will be described.
When assembling the butterfly valve 1, the mounting of the valve box-side shaft sealing material 12 is performed as follows.
[0042]
As shown in FIG. 4, the two seal pieces 18a and 18b are fitted into the mounting grooves 19 and set on the inner peripheral surface of the valve box 2. Then, the valve box sheet 7 is inserted into the valve box 2, and the valve box sheet is inserted. The position of the through hole 9 of 7 is matched with the position of the boss hole 8 a of the boss 8. As a result, the two seal pieces 18a and 18b seal the gap 17 between the valve box 2 and the valve box sheet 7 on the upstream side and the downstream side of the flow path, and each end A of both the seal pieces 18a and 18b is It protrudes from the mounting groove 19 into the boss hole 8a.
[0043]
Next, the valve box-side shaft sealing material 12 is inserted from the inside of the valve box sheet 7 into the through hole 9 and the boss hole 8a. At this time, the end portions A of the protruding seal pieces 18a and 18b are inserted into the two groove portions 31 from the outer end surface 12a of the valve box side shaft seal material 12. As a result, the end portions A of the sealing pieces 18a and 18b protruding into the boss hole 8a do not become an obstacle as in the related art, and the valve box side shaft seal material 12 can be easily inserted into the through hole of the valve box sheet 7. 9 and the boss hole portion 8a of the boss portion 8, which solves the problem of difficulty in mounting the valve box side shaft sealing material 12. At this time, a portion from the inner end of the groove 31 to the inner end surface 12b of the valve box side shaft sealing material 12 fits into the through hole 9 of the valve box sheet 7.
[0044]
Thereafter, as shown by the solid line in FIG. 5, the bearing member 10 is inserted into the boss hole 8a of the boss portion 8 from the outside. At this time, both the pressing members 32 are inserted into the two groove portions 31 of the valve box-side shaft sealing seal material 12. Plug in. Further, as shown in FIG. 6, the valve stem 5, the valve body 6, and the valve body side shaft sealing material 13 are assembled, the stopper 20 is attached, and the valve box sheet 7 is fixed. Attach to the boss 8 with.
[0045]
When the butterfly valve 1 is assembled in this manner, as shown in FIG. 6, the holding plate 15 is tightened with the tightening bolts 16, so that the valve box-side shaft sealing material 12 is The shaft seal material 13 is pressed against the shaft seal material 13 so that the two shaft seal materials 12 and 13 are in sliding contact with each other in a water-tight manner. The boss portion 8 comes into pressure contact with the inner peripheral surface of the boss hole portion 8a to exhibit sealing performance.
[0046]
When the valve element 6 rotates, the valve element-side shaft sealing material 13 rotates while sliding on the valve box-side shaft sealing material 12 in a watertight manner. Thereby, the fluid flowing through the internal flow path of the valve box sheet 7 does not leak around the valve stem 5.
[0047]
Further, by pressing the holding plate 15 with the tightening bolts 16 as described above, when the bearing member 10 presses the valve box side shaft sealing seal material 12 against the valve body side shaft sealing seal material 13, both pressing members 32 The inside of the groove 31 is pushed toward the inner end surface 12b of the valve box-side shaft sealing material 12, and each end A of both the sealing pieces 18 a, 18 b inserted into the both grooves 31 is pressed by the two pressing members 32 into the valve box. It is pressed by the side shaft sealing material 12. Thus, even if the amount of protrusion of the ends A of the seal pieces 18a, 18b into the boss hole 8a is slightly different, the ends A of the seal pieces 18a, 18b and the valve box-side shaft seal material 12 And the water stoppage between them is stably and sufficiently secured.
[0048]
Since the inner end 32a of the pressing member 32 is formed of an elastic material, the inner end 32a comes into pressure contact with the inner peripheral surface of the boss hole 8a, and the sealing of this portion can be performed reliably.
[0049]
In the first embodiment, as shown in FIG. 1, the pressing member 32 is provided integrally with the bearing member 10, but the pressing member 32 may be separately provided from the bearing member 10. Further, as shown in FIG. 7, the pressing member 32 may be formed integrally with each end of the seal pieces 18a and 18b.
[0050]
Next, a second embodiment will be described with reference to FIGS.
The valve box-side shaft seal member 12 is divided into a ring-shaped main seal portion 40 that is in pressure contact with the bearing member 10 and a ring-shaped auxiliary seal portion 41 that is in contact with the valve body-side shaft seal member 13. I have. Note that the thickness of the sub-sealing portion 41 matches the thickness of the valve box sheet 7.
[0051]
One end of each of the seal pieces 18a and 18b is formed integrally with the outer peripheral surface of the main seal portion 40 of one of the valve box-side shaft seal materials 12, and the other end of each of the seal pieces 18a and 18b is the other. Is formed integrally with the outer peripheral surface of the main seal portion 40 of the valve box side shaft seal material 12. The inner peripheral edges of the ends of the seal pieces 18a and 18b are flush with the inner end surface of the main seal portion 40 (that is, the surface facing the sub seal portion 41).
[0052]
Hereinafter, the operation of the above configuration will be described.
When assembling the butterfly valve 1, the mounting of the valve box-side shaft sealing material 12 is performed as follows.
[0053]
Since the two seal pieces 18a and 18b and the main seal portion 40 of the valve box-side shaft seal member 12 are integral, first, as shown in FIG. The seal pieces 18 a and 18 b are inserted into the boss holes 8 a of the boss section 8 from the inside, and are fitted into the mounting grooves 19 to be set on the inner peripheral surface of the valve box 2. Thereafter, as shown in FIG. 10B, the valve box sheet 7 is inserted into the valve box 2, and the position of the through hole 9 of the valve box sheet 7 is matched with the position of the boss hole 8 a of the boss 8, Next, as shown in FIG. 10C, the sub-seal portions 41 of the valve-box-side shaft sealing materials 12 are fitted into the through holes 9 from inside the valve box sheet 7.
[0054]
In this way, by forming the two sealing pieces 18a and 18b and the main sealing portion 40 of the valve-box-side shaft sealing material 12 not as separate bodies but as an integral body, the main sealing portion 40 can be easily formed by the boss of the boss portion 8. It can be fitted into the hole 8a. Further, after that, by fitting the sub-seal portion 41 into the through hole 9 from inside the valve box sheet 7, the valve-box-side shaft seal member 12 is constituted by the main seal portion 40 and the sub-seal portion 41. The problem of difficulty in mounting the valve box-side shaft sealing material 12 is solved.
[0055]
The two seal pieces 18a and 18b seal the gap 17 between the valve box 2 and the valve box sheet 7 on the upstream side and the downstream side of the flow path. Thereafter, as shown in FIG. 9, the bearing member 10 is inserted into the boss hole 8a of the boss portion 8, the valve rod 5, the valve body 6, and the valve body-side shaft sealing material 13 are assembled, and the stopper 20 is attached. After fixing the valve box sheet 7 by pressing, the holding plate 15 is attached to the boss 8 with the tightening bolt 16.
[0056]
When the butterfly valve 1 is assembled as described above, the holding plate 15 is tightened with the tightening bolts 16, so that the valve-box-side shaft-sealing material 12 is pressed against the valve-body-side shaft-sealing material 13 via the bearing member 10. As a result, the main seal portion 40 and the sub seal portion 41 are pressed against each other to seal the two seal portions 40, 41, and the sub seal portion 41 and the valve body-side shaft seal material 13 are watertight with each other. The outer peripheral surface of the auxiliary seal portion 41 is pressed against the peripheral edge of the through hole 9 of the valve box sheet 7 to exert sealing performance, and the outer peripheral surface of the main seal portion 40 is boss hole of the boss portion 8. The sealing performance is exhibited by pressing against the inner peripheral surface of the portion 8a.
[0057]
When the valve element 6 rotates, the valve element-side shaft sealing material 13 rotates while sliding on the valve box-side shaft sealing material 12 in a watertight manner. Thereby, the fluid flowing through the internal flow path of the valve box sheet 7 does not leak around the valve stem 5.
[0058]
Further, since the two seal pieces 18a, 18b and the main seal portion 40 of the valve box-side shaft sealing material 12 are integrally formed, the gap between the ends of the two seal pieces 18a, 18b and the main seal portion 40 is formed. The water-stopping property is stably and sufficiently secured.
[0059]
In the second embodiment, as shown in FIG. 8, the valve box-side shaft seal member 12 is divided into the main seal portion 40 and the sub seal portion 41. However, such a divided structure is not necessary. . That is, as a third embodiment, as shown in FIG. 11, one end portions of both seal pieces 18a and 18b are integrally formed on the outer peripheral surface of one valve box side shaft seal material 12, respectively. The other ends of 18a and 18b are formed integrally with the outer peripheral surface of the other valve-box-side shaft seal member 12, respectively. The distance H from the inner peripheral edge of the end portion of each of the seal pieces 18a and 18b to the inner end surface 12b of the valve box-side shaft sealing material 12 matches the thickness of the valve box sheet 7.
[0060]
Hereinafter, the operation of the above configuration will be described.
When assembling the butterfly valve 1, the mounting of the valve box-side shaft sealing material 12 is performed as follows.
[0061]
Since both seal pieces 18a, 18b and both valve box-side shaft seal materials 12 are integrated, first, as shown by the solid line in FIG. From inside, each is inserted into the boss hole portion 8a of the boss portion 8, and both seal pieces 18a and 18b are fitted into the mounting grooves 19 and set on the inner peripheral surface of the valve box 2.
[0062]
Thereafter, the valve box sheet 7 is inserted into the valve box 2. At this time, as shown by the imaginary line in FIG. 11A, the both valve box side shaft sealing seals are arranged such that the inner end faces 12 b of the both valve box side shaft sealing materials 12 are located outside the valve box sheet 7. The material 12 is moved outward (at this time, the sealing pieces 18a and 18b are slightly elongated because they are elastic bodies). After the valve box sheet 7 is inserted into the valve box 2 in this manner, the position of the through hole 9 of the valve box sheet 7 is changed to the position of the boss hole 8a of the boss 8 as shown in FIG. The inner ends of the valve box-side shaft sealing material 12 are fitted into the through holes 9 (at this time, the sealing pieces 18a and 18b shrink to their original lengths).
[0063]
In this way, the two seal pieces 18a, 18b and the valve box-side shaft sealing seal material 12 are not integrated but are integrated, so that the valve box-side shaft sealing seal material 12 can be easily inserted into the through hole of the valve box sheet 7. 9 and the boss hole portion 8a of the boss portion 8, which solves the problem of difficulty in mounting the valve box-side shaft seal member 12.
[0064]
Thereafter, the bearing member 10 was inserted into the boss hole 8a from the outside, and the valve rod 5, the valve body 6, and the valve body-side shaft sealing seal material 13 were assembled, the stopper 20 was attached, and the valve box sheet 7 was fixed. Thereafter, the holding plate 15 is mounted on the boss 8 with the tightening bolt 16.
[0065]
When the butterfly valve 1 is assembled as described above, the holding plate 15 is tightened with the tightening bolts 16, so that the valve-box-side shaft-sealing material 12 is pressed against the valve-body-side shaft-sealing material 13 via the bearing member 10. As a result, the two shaft sealing materials 12 and 13 are in sliding contact with each other in a watertight manner, and the outer peripheral surface of the valve box side shaft sealing material 12 The sealing performance is exhibited by pressing against the inner peripheral surface of the hole 8a.
[0066]
When the valve element 6 rotates, the valve element-side shaft sealing material 13 rotates while sliding on the valve box-side shaft sealing material 12 in a watertight manner. Thereby, the fluid flowing through the internal flow path of the valve box sheet 7 does not leak around the valve stem 5.
[0067]
Further, since the seal pieces 18a, 18b and the valve box-side shaft sealing seal material 12 are integrally formed, the water stopping property between the ends of the seal pieces 18a, 18b and the valve box-side shaft sealing seal material 12 is formed. Is stable and sufficiently secured.
[0068]
【The invention's effect】
As described above, according to the present invention, at the time of assembling, the mounting of the valve box-side shaft sealing seal material can be easily performed, and further, the gap between the end of the sealing piece and the valve box-side shaft sealing seal material is provided. Water stoppage can be stably and sufficiently secured.
[Brief description of the drawings]
FIG. 1 is a perspective view of a bearing member of a butterfly valve and a valve box-side shaft sealing seal member according to a first embodiment of the present invention, wherein (a) is a bearing member, and (b) is a valve box-side shaft seal. 3 shows a sealing material.
FIG. 2 is a perspective view showing a combination of a bearing member of a butterfly valve, a valve box-side shaft sealing material, and a sealing piece.
FIG. 3 is a sectional view showing a combination of a bearing member of a butterfly valve, a valve box side shaft seal material, a sealing piece, and a valve box sheet.
FIG. 4 is a cross-sectional view showing a procedure for mounting a valve box-side shaft seal member of the butterfly valve.
FIG. 5 is a cross-sectional view showing a procedure for mounting a valve-box-side shaft sealing seal member of the butterfly valve.
FIG. 6 is a sectional view of a shaft sealing portion of the butterfly valve.
FIG. 7 is a sectional view showing a combination of a bearing member of a butterfly valve, a valve box side shaft seal material, a sealing piece, and a valve box sheet according to another embodiment.
FIG. 8 is a diagram of an O-ring of a butterfly valve and a valve box-side shaft sealing material according to a second embodiment of the present invention.
FIG. 9 is a cross-sectional view of a combination of a bearing member of a butterfly valve, a valve box-side shaft sealing material, a sealing piece, and a valve box sheet.
FIG. 10 is a cross-sectional view showing a procedure for mounting the valve box-side shaft seal material of the butterfly valve, in which (a) shows a state in which a seal piece and a main seal portion of the valve box side shaft seal material are mounted. (B) shows a state in which a valve box sheet is mounted, and (c) shows a state in which a sub seal portion of a valve box side shaft seal material is mounted.
FIG. 11 is a cross-sectional view showing a procedure for mounting a valve box side shaft sealing seal material of a butterfly valve according to a third embodiment of the present invention, wherein (a) shows a sealing piece and a valve box side shaft sealing seal material; (B) shows a state where the valve box sheet is mounted.
FIG. 12 is a longitudinal sectional view of a conventional butterfly valve as viewed from the front.
FIG. 13 is a vertical sectional view of the butterfly valve as viewed from a side surface thereof.
FIG. 14 is a cross-sectional view of the butterfly valve as viewed from a valve shaft axis.
FIG. 15 is a sectional view of a shaft sealing portion of the butterfly valve.
FIG. 16 is a perspective view showing a state in which a valve box-side shaft sealing material is fitted into a through hole of a valve box sheet of the butterfly valve.
FIG. 17 is a cross-sectional view showing a procedure for mounting a valve box-side shaft seal material of the butterfly valve.
[Explanation of symbols]
1 butterfly valve
2 Valve box
3 Flow axis
4 axis center
5 Valve stem
6 valve body
7 Valve box sheet
8 Boss
9 Through hole
10 Bearing members
11 Valve seat
12 Valve box side shaft seal material
13 Sealing material for shaft seal on valve body
14 Tightening means
17 gap
18 O-ring (valve box sealing material)
18a, 18b Seal piece
31 groove
32 pressing member
A end
