JP4570274B2

JP4570274B2 - Bidirectional shut-off valve for gas meter

Info

Publication number: JP4570274B2
Application number: JP2001122666A
Authority: JP
Inventors: 豊田中
Original assignee: Aichi Tokei Denki Co Ltd
Current assignee: Aichi Tokei Denki Co Ltd
Priority date: 2001-04-20
Filing date: 2001-04-20
Publication date: 2010-10-27
Anticipated expiration: 2021-04-20
Also published as: JP2002317875A

Description

【０００１】
【発明の属する技術分野】
本発明は安全機能付ガスメータに用いる双方向遮断弁に関する。
【０００２】
【従来の技術】
ガス使用時における様々な異常使用状態が内蔵のマイコンにプログラムされており、流量異常や長時間にわたるガスの異常使用が発生すると、マイコンが判断して、直ちにガスを遮断する安全機能付ガスメータ（単にマイコンメータともいう）が広く用いられている。遮断弁はいわゆる自己保持型電磁弁が使われていて、一時的に駆動電流を流すと閉弁してガスの供給を遮断し、駆動電流を断ったあと、スプリングの力で閉弁状態を保持する。そして、逆方向の駆動電流を流すと開弁して、駆動電流を断ったあと、マグネット（永久磁石）の磁力で開弁状態を保持する。このように、電気的に閉弁方向と開弁方向への両方向の作動ができるので、双方向遮断弁と呼ばれている。なお、大型のガスメータでは、電磁弁ではなく電動弁が用いられるが、双方向作動できる点は電磁弁と同じである。
【０００３】
図９にこの種の双方向遮断弁（以下、単に遮断弁という）で構造が電磁弁のものを示す。１はガスメータの上ケースの一部分を構成する遮断弁取付部で、この遮断弁取付部１に弁座２が一体的に形成されている。遮断弁取付部１にパッキン３を介してホルダ４が取付ネジ５で固着されている。ホルダ４にはコイル６を巻いたボビン７が装着されている。図は閉弁状態を示す。プランジャ（可動鉄心）８はコア（固定鉄心）９から離れて図示左方の位置にある。このとき、弁ゴム１０は弁フレーム１１とともに第１のスプリング１２により図示左方に付勢されて、弁座２に押圧されて密着し閉弁状態にある。第２のスプリング１３は、プランジャ８の小径部８ａに嵌装された第１のスプリングホルダ１４と、前記弁ゴム１０の中央部左側面に当接した第２のスプリングホルダ１５との間に装架され、プランジャ８を図示左方に付勢して、プランジャ８を図示の位置に保持している。１６はプランジャ８の小径部８ａの左端部に嵌合したＥリングで、第１のスプリングホルダ１４の抜け止めである。なお、図の状態で、第２のスプリング１３の荷重（ばね力）は第１のスプリング１２の荷重（ばね力）よりも小さい。
【０００４】
図示の閉弁状態のときには、ガスメータの図示されてない入口に連通する１次側１７のガス圧が、ガスメータの図示されてない計量室に連通する２次側１８のガス圧よりガス供給圧分だけ高い値にあって、この圧力差による分と、第１のスプリング１２による付勢力とで弁ゴム１０が弁座２に押し付けられている。この閉弁状態から開弁するには、コイル６に一時的に駆動電流を流すと、プランジャ８がコア９に吸引され、先ず弱い力の第２のスプリング１３に抗してわずかに図示右方に移動してプランジャの段部８ｂが弁ゴム１０の面１０ａから右方に離れる（図１０参照）。すると、弁ゴム１０の内径とプランジャ８の外径との間の隙間を通って、１次側１７から２次側１８へと矢印Ａのようにガスが流れて弁ゴム１０にかかっていた前記圧力差が小さくなる。そこで、プランジャ８は第１のスプリング１２に抗して一気に右方へ移動して、弁ゴム１０が弁座２から離れ、プランジャ８の右端がコア９に吸着されて、開弁状態が保持される。１９はマグネット（永久磁石）で、駆動電流を断ったあとの開弁状態を保持する（図１１参照）。開弁状態では１次側１７から２次側１８へ矢印Ｂで示すようにガスが流れる。
【０００５】
開弁状態にあるときに、前記開弁駆動時と逆向きの駆動電流を一時的にコイル６に流すと、マグネット１９による保持力が解除されて、プランジャ８、弁フレーム１１及び弁ゴム１０等が第１のスプリング１２の付勢力で図示左方に移動して弁ゴム１０が弁座２に押圧されて閉弁する。プランジャ８の段部８ｂは弁ゴム１０の側面１０ａに当り、この部分も閉じて図９に示す状態となる。なお、開弁駆動時に１次側１７の圧力を２次側１８に抜くための段部８ｂ、弁ゴム１０の内径とプランジャ８の外径との隙間及び第２のスプリング１３等で構成される機構を副弁と呼んでいる。図９〜１１ではこの副弁に符号２０を付する。
【０００６】
【発明が解決しようとする課題】
前記従来の技術では、閉弁時、弁ゴム１０を弁フレーム１１で弁座２の平らな座面に押し付けて、弁ゴム１０の厚み方向に圧縮するようにしていた。そして弁の漏れを防ぐため、一定以上の弁荷重を加えてシール性を確保しているため、弁を開く場合に、前記弁荷重に打ち勝つ電磁力が必要となり、電磁弁の駆動電力が大きくなるという問題点があった。
【０００７】
また、現在の家庭用ガスメータの弁荷重は、漏れを防止するために弁座の周長に対して１ｇ／ｍｍ以上を必要としており、開弁時の駆動電力を減らそうとすると、弁荷重が弁座の周長に対して１ｇ／ｍｍ以下になり、弁のシール性が悪くなるという問題点があった。実際に弁ゴムの径のφ３０の従来技術では、１次と２次の圧力差による荷重が約１５０ｇ、第１のスプリングの荷重が約１００ｇであった。
【０００８】
そこで、本発明は、このような問題点を解消できるガスメータ用双方向遮断弁を提供することを目的とする。
【０００９】
【課題を解決するための手段】
前記目的を達成するために、請求項１の発明は、弁ゴムの周縁に、閉弁時の荷重で撓み変形するリップ状部分を形成し、該弁ゴムの周縁リップ状部分を断面Ｕ字形に形成したことを特徴とするガスメータ用双方向遮断弁である。
【００１２】
請求項２の発明は、請求項１のガスメータ用双方向遮断弁において、弁座の弁座面に弁ゴムが接地して生じる環状の接地部において、円周方向の一部に接地面積が小さい接地面積小の部分を形成したことを特徴とするものである。
【００１３】
請求項３の発明は、請求項１のガスメータ用双方向遮断弁において、弁座の弁座面に弁ゴムが接地して生じる環状の接地部の半径方向の幅を円周の一部において小さくしたことを特徴とするものである。
【００１４】
請求項４の発明は、弁ゴムの周縁に、閉弁時の荷重で撓み変形するリップ状部分を形成し、
弁座面の内周にかかる部分の一部に傾斜面からなる切欠部を形成することにより、弁座の弁座面に前記弁ゴムが接地して生じる環状の接地部において、円周方向の一部に接地面積が小さい接地面積小の部分を形成し、
前記弁ゴムにおける、前記接地部分より内側を、弁座面とは反対側に湾曲する湾曲状に形成したことを特徴とするガスメータ用双方向遮断弁である。
請求項５の発明は、弁ゴムの周縁に、閉弁時の荷重で撓み変形するリップ状部分を形成し、
弁座面の内周にかかる部分の一部に傾斜面からなる切欠部を形成することにより、弁座の弁座面に前記弁ゴムが接地して生じる環状の接地部の半径方向の幅を円周の一部において小さくし、
前記弁ゴムにおける、前記接地部分より内側を、弁座面とは反対側に湾曲する湾曲状に形成したことを特徴とするガスメータ用双方向遮断弁である。
請求項６の発明は、請求項２又は３のガスメータ用双方向遮断弁において、弁座面の一部、特に内周にかかる部分に傾斜面からなる切欠部を形成したことを特徴とするものである。
【００１５】
請求項７の発明は、弁ゴムの周縁に、閉弁時の荷重で撓み変形するリップ状部分を形成し、
弁ゴムの外周の一部に切欠部を形成して、弁座の弁座面に弁ゴムが接地して生じる環状の接地部において、円周方向の一部に接地面積が小さい接地面積小の部分を形成したことを特徴とするガスメータ用双方向遮断弁である。
請求項８の発明は、弁ゴムの周縁に、閉弁時の荷重で撓み変形するリップ状部分を形成し、
弁ゴムの外周の一部に切欠部を形成して、弁座の弁座面に弁ゴムが接地して生じる環状の接地部の半径方向の幅を円周の一部において小さくしたことを特徴とするガスメータ用双方向遮断弁である。
請求項９の発明は、請求項２又は３のガスメータ用双方向遮断弁において、弁ゴムの外周の一部に切欠部を形成したことを特徴とするものである。
【００１６】
請求項１０の発明は、請求項１〜９のいずれかのガスメータ用双方向遮断弁において、開弁動作時に１次側から２次側へガス圧を抜く副弁を備えたことを特徴とするものである。
【００１７】
【発明の実施の形態】
次に本発明の好ましい実施の形態をいくつかの実施例に従って説明する。
【００１８】
〔実施例１〕
図１の実施例１において、弁ゴム１０Ａは、弁フレーム１１Ａに嵌合したままプランジャ８Ａの図示左端部に嵌合され、プランジャ８Ａから外れないように座金２１とＥリング２２で装着されている。弁ゴム１０Ａを閉弁方向に付勢するスプリング１２Ａの荷重は、前記従来の技術で説明した図９の第１のスプリング１２の荷重より小さくしてある。弁座２Ａは、ガスメータ上ケースの一部を構成する遮断弁取付部１Ａに別体として形成した弁座を嵌合して構成している。こうすることで、弁座を遮断弁取付部に直接一体的に形成する図９の場合と比較して、弁座の座面の平面度の加工精度を出しやすく、その分弁荷重が小さくても閉弁時のシール性が良くなる。
【００１９】
弁ゴム１０ＡはＮＢＲ製で、その周縁部は０．３〜１ｍｍ程度の薄いリップ状に形成されていて、スプリング１２Ａの荷重と前記圧力差で弁座２Ａに押圧されると、しなやかに撓んで図示のように変形し、弁座２Ａの座面に密接して確実にガスをシールする。弁ゴム１０Ａと弁フレーム１１Ａの間には隙間２３が形成され、弁ゴム１０Ａが弁フレーム１１Ａの存在によらず容易にプランジャ８Ａの軸線方向（図示左右方向）に撓みやすいようにしてある。
【００２０】
弁座２Ａは図２に示すように、平らな座面２ａと内周２ｂにかかるように、円周の一部に傾斜面２ｃによる切欠部を形成している。こうすることで、座面２ａに弁ゴム１０Ａが接してガスをシールする接地部分の接地面積小の部分２ｄを形成している。換言すると、座面２ａの半径方向の幅ΔＲが、前記傾斜面２ｃによる切欠部の存在で小さい幅Δｒになっている。こうすることで、閉弁時に弁ゴムにかかる圧力差が部分２ｄでは他の部分よりも小さくなる。そのため、閉弁状態から開弁動作に入ると、この部分２ｄ辺りの弁ゴム１０Ａが部分的に少し浮くか又はリップ状部分が変形して一番始めに開となり、１次、２次圧が同圧となり、弁が開きやすくなる。つまり軽く開く。このような作用を得るには、弁座２Ａの一部に傾斜面による切欠部を形成する代わりに弁ゴムの外周の一部に切欠を設けて、結果的にこの部分の接地面積を小としても良い（後述する実施例３も参照）。
【００２１】
〔実施例２〕
本発明の要点は双方向遮断弁の弁ゴムと弁座回りにあるので、この実施例２では弁ゴムと弁フレームの形状のいくつかの例を図３（ａ）（ｂ）及び（ｃ）に示す。なお、これらの図では、弁ゴムや弁フレームの中央部、特に図示されてないプランジャに装着する部分の形状は簡略化して示していて実際と異なる。図３（ａ）は、弁ゴム１０Ｂの断面が細い三日月形の例で、この例の場合、弁フレームは無い。弁ゴム１０Ｂはリップ状の周縁部を含む全体がＮＢＲ製の薄板で一体的に形成される。この例の弁ゴム１０Ｂの断面形状は図１の実施例１の場合に似ている。図３（ｂ）は弁ゴム１０Ｃがリップ状の周縁部を含め、全体が厚み０．３〜１ｍｍのＮＢＲ製の薄板で構成され、弁フレーム１１Ｃが、その中央部以外が弁ゴム１０Ｃと離れ、両者の間に隙間２３ｃがある。図３（ｃ）の例は、弁ゴム１０Ｃが同図（ｂ）の例と同じであるが、弁フレーム１１Ｄが同図（ｂ）の例よりもその断面の曲率が大きい球面の一部を形成していて、弁フレーム１１Ｄの周縁だけが弁ゴム１０Ｃと接し、他の部分を離し両者の間に隙間２３Ｄを設けた。
【００２２】
〔実施例３〕
図４（ａ）に示す実施例３は、ガスメータ上ケースの一部分を構成する遮断弁取付部１Ａに弁座２が一体的に形成されている。弁座２の平らな弁座面２ａは、ＮＢＲ製の０．３〜１ｍｍ厚の薄板からなる弁ゴム１０Ｃと協働する。
【００２３】
遮断弁の電磁駆動部ＥＭのコイルに一時的に駆動電流を流してプランジャ８Ａをスプリング１２Ａの荷重で図示左方に動かすと、弁ゴム１０Ｃが符号１０Ｃ′の位置に移動して、そのリップ状の周縁部が弁座２の弁座面２ａに圧接する。このときリップ状の周縁部はしなやかに撓んで、弁座面２ａに密着してガスを確実にシールする。この実施例では同図（ｂ）に示すように弁ゴムの外周に切欠Ｋを設けることで、弁座面２ａに弁ゴム１０Ｃが接地する環状部分に接地面積小の部分２ｄ′を設けた。こうして、図１，図２の実施例１の場合のように、開弁動作時に弁座面から弁ゴムが離れやすくなって、開弁時の消費電力を低減する。
【００２４】
なお、符号２０で示すように、図９の従来技術の場合と同じような副弁を設け、開弁動作に入るときのガス抜きを行うようにしても良い。
【００２５】
〔実施例４〕
図５に示す実施例４は、図４の実施例３と比較して、弁座面の形状と弁ゴムの形状などが異なっているので、これらの部分を説明し、実施例３と同じ部分は同一符号を付して説明を省略する。この実施例では、図４の弁ゴム１０Ｃの周縁部に断面がＵ字形のリップ状部分１０ｅを形成して弁ゴム１０Ｅを構成し、弁座２の内周壁２ｅもシール面としている。符号１０Ｅ′は閉弁時の弁ゴムで周縁部が弁座面２ｅに密着してガスをシールしている。この実施例においても符号２０を付したように副弁を設けてもよい。この実施例４では、弁ゴムの周縁部のリップ状部分１０ｅを断面Ｕ字形にしたので、小スペースでシール面積を広くでき、弁座面２ｅの外径が小さくでき、弁が小型になる。従って、１次側１７の内径ΦＮを図４の実施例３に比較して小さくできる。また、弁ゴムの成形が実施例３の形状より寸法的に自由度が大きい利点がある。
【００２６】
〔実施例５〕
図６に示す実施例５は、図１の実施例１と比較して、弁座の形状と弁ゴムの形状だけが異なっているので、実施例１と同じ部分は同一符号を付してその説明を省略する。この実施例では、弁座２Ｂは、その座面に直径φの環状突条２ｆを有し、閉弁時はこの環状突条２ｆに図示のように弁ゴム１０Ｆが押圧されてガスをシールする。このとき弁ゴム１０Ｆは、その中心即ちプランジャ８Ａの軸線から距離φ／２までの部分がしなやかに撓んで変形して環状突条２ｆに密着シールする。Φは弁ゴムの外径で前記直径φより大きく定めてある。
【００２７】
〔実施例６〕
図７の実施例６は、図６の実施例と同様の環状突条２ｆに、ＮＢＲ製の厚み０．３〜１ｍｍの円形薄板からなる弁ゴム１０Ｃと、環状突条２ｆの直径φより小さい外径の球面状の弁フレーム１１Ｃとでシール部回りの構造ができている。なお、図７では実際に用いられるプランジャやスプリング等は省略して図示してない。この実施例においても他の実施例と同様に、弁ゴムのリップ状周縁部がしなやかに撓んで弁座面２ｆに密着してガスをシールするので、小さい弁荷重でも確実にシールして弁漏れを防止する。
【００２８】
〔実施例におけるシール構造の分類〕
上記いくつかの実施例のシール構造を図８に分類して示す。同図において、（ａ）は周縁部をリップ状に形成したＮＢＲ製の弁ゴム１０Ｃを弁座２Ａの平らな弁座面２ａに対向配置したもので、弁座２Ａの円周の一部に傾斜面（スロープ）２ｃからなる切欠部を形成している。この例では、平らな弁座面２ａに沿って弁ゴム１０Ｃのリップ状周縁部が撓んで密着し、ガスをシールする。同図（ｂ）のものは、ＮＢＲ製の弁ゴム１０Ｅの周縁リップ状部分１０ｅを断面Ｕ字形に形成し、弁座２の内周壁（弁座面）２ｅをシール面としている。同図（ｃ）はＮＢＲ製の全体がほぼ球面の一部分を形成する弁ゴム１０Ｃの球面の内側を弁座２Ｂの環状突条２ｆに密着してシールする構造である。なお、同図（ｄ）は、同図（ａ）における弁座面を示す図で、符号２４は弁ゴム１０Ｃの外径を示す。ΔＲ′は、弁ゴム１０Ｃの外径から弁座の内周２ｂの直径を差し引いた直径差の半分である半径差で、この幅ΔＲ′の環状部分が弁座面２ａに弁ゴムの周縁リップ状部分が密着接地する接地部分となる。円周の一部分では、傾斜面２ｃによる切欠部によって前記幅ΔＲ′が小さい幅Δｒ′となっている。２ｄは実施例１で説明した接地面積小の部分に相当する。
【００２９】
なお、前記本発明の実施例では、スプリング１２Ａの荷重を２０ｇまで軽減しても良好なシール性を保持でき、ガス漏れを確実に防止できた。
【００３０】
【発明の効果】
本発明のガスメータ用双方向遮断弁は上述のように構成されているので、小さな弁荷重でのシール性を確保でき、結果として開弁時の電力を低減でき、ガスメータの低消費電力化に役立つ。因みに、弁ゴムがしなやかに撓んで柔軟に弁座面へ密着するので、弁荷重を０．１ｇ／ｍｍまで減らしてもシール性が確保できた。そして請求項２の発明では、それに加えて弁ゴムの断面Ｕ字形の外周縁が接する弁座の内周壁もシール面として活用できるので、弁座のシール面の外径が小さくでき、弁が小型になる。従って、ガスメータの構造が複雑で遮断弁用のスペースがとれないときでも、小スペースで接地面積を広くできる。また、弁ゴムの成形寸法の自由度が大きい。
【００３１】
請求項２〜９の発明では、更に開弁動作時に、弁ゴムの円周の一部が弁座面から離れやすくなって、その分開弁時の電力をより低減できる。
【００３２】
請求項１０の発明では、開弁動作時に副弁の作用でガス差圧による弁荷重がなくなるので、より一層開弁時の電力を低減できる。
【図面の簡単な説明】
【図１】本発明の実施例の縦断面図。
【図２】図１の実施例の弁座の斜視図。
【図３】本発明の実施例の弁ゴムと弁フレームの異なる形状の組み合わせを説明する縦断面図。
【図４】本発明の実施例で、（ａ）は全体の一部縦断面図、（ｂ）は弁ゴムを同図（ａ）の右側から見た図。
【図５】本発明の実施例の一部縦断面図。
【図６】本発明の実施例の縦断面図。
【図７】本発明の実施例の要部縦断面図。
【図８】本発明の実施例のシール構造を示す図で、（ａ）（ｂ）（ｃ）は縦断面図、（ｄ）は同図（ａ）の弁座を図の右から見た図。
【図９】従来技術の縦断面図。
【図１０】従来技術の異なる態様の縦断面図。
【図１１】従来技術の異なる態様の縦断面図。
【符号の説明】
１遮断弁取付部
２，２Ａ弁座
２ａ弁座面
２ｂ内周
２ｃ傾斜面
２ｄ，２ｄ接地面積小の部分
２ｅ内周壁（弁座面）
２ｆ環状突条
ΔＲ，ΔＲ′，Δｒ，Δｒ′ 半径方向の幅
１０Ａ．１０Ｂ，１０Ｃ，１０Ｅ，１０Ｆ弁ゴム
２０副弁 [0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bidirectional shutoff valve used for a gas meter with a safety function.
[0002]
[Prior art]
Various abnormal usage conditions when using gas are programmed in the built-in microcomputer, and when a flow rate abnormality or abnormal use of gas for a long time occurs, the microcomputer will judge and immediately shut off the gas with a safety function (simply simply (Also called a microcomputer meter) is widely used. A so-called self-holding solenoid valve is used as the shut-off valve. When a drive current is temporarily applied, the valve is closed to shut off the gas supply. After the drive current is cut off, the valve is kept closed by the force of the spring. To do. Then, when a drive current in the reverse direction is applied, the valve is opened, and after the drive current is cut off, the valve open state is maintained by the magnetic force of a magnet (permanent magnet). In this way, since it can be electrically operated in both the valve closing direction and the valve opening direction, it is called a bidirectional shut-off valve. In a large gas meter, a motorized valve is used instead of a solenoid valve, but it is the same as a solenoid valve in that it can be operated bidirectionally.
[0003]
FIG. 9 shows this type of bidirectional shut-off valve (hereinafter simply referred to as a shut-off valve) having an electromagnetic valve structure. Reference numeral 1 denotes a shut-off valve mounting portion constituting a part of the upper case of the gas meter, and a valve seat 2 is formed integrally with the shut-off valve mounting portion 1. A holder 4 is fixed to the shut-off valve mounting portion 1 with a mounting screw 5 via a packing 3. A bobbin 7 around which a coil 6 is wound is mounted on the holder 4. The figure shows the valve closed state. The plunger (movable iron core) 8 is away from the core (fixed iron core) 9 and is at the left position in the figure. At this time, the valve rubber 10 is urged to the left in the drawing by the first spring 12 together with the valve frame 11 and is pressed against the valve seat 2 to be in close contact with each other. The second spring 13 is mounted between the first spring holder 14 fitted to the small diameter portion 8 a of the plunger 8 and the second spring holder 15 in contact with the left side surface of the central portion of the valve rubber 10. The plunger 8 is urged to the left in the figure to hold the plunger 8 at the position shown in the figure. Reference numeral 16 denotes an E-ring fitted to the left end portion of the small-diameter portion 8a of the plunger 8 and serves to prevent the first spring holder 14 from coming off. In the state shown in the figure, the load (spring force) of the second spring 13 is smaller than the load (spring force) of the first spring 12.
[0004]
In the valve closing state shown in the figure, the gas pressure on the primary side 17 communicating with the inlet (not shown) of the gas meter is equal to the gas supply pressure than the gas pressure on the secondary side 18 communicating with the metering chamber (not shown) of the gas meter. The valve rubber 10 is pressed against the valve seat 2 by the pressure difference and the urging force of the first spring 12. To open the valve from this closed state, when a drive current is temporarily applied to the coil 6, the plunger 8 is attracted to the core 9, and first, slightly against the second spring 13 with a weak force slightly to the right in the figure. The plunger step 8b moves to the right from the surface 10a of the valve rubber 10 (see FIG. 10). Then, the gas flowed from the primary side 17 to the secondary side 18 as indicated by the arrow A through the gap between the inner diameter of the valve rubber 10 and the outer diameter of the plunger 8 and applied to the valve rubber 10. The pressure difference becomes smaller. Accordingly, the plunger 8 moves rightward against the first spring 12 at once, the valve rubber 10 is separated from the valve seat 2, and the right end of the plunger 8 is adsorbed by the core 9, so that the valve open state is maintained. The Reference numeral 19 denotes a magnet (permanent magnet) which holds the valve open state after the drive current is cut off (see FIG. 11). In the valve open state, gas flows from the primary side 17 to the secondary side 18 as indicated by an arrow B.
[0005]
When in the valve open state, when a drive current in the opposite direction to that during the valve opening drive is temporarily passed through the coil 6, the holding force by the magnet 19 is released, and the plunger 8, the valve frame 11, the valve rubber 10, etc. Is moved to the left in the figure by the urging force of the first spring 12, and the valve rubber 10 is pressed against the valve seat 2 to close the valve. The step portion 8b of the plunger 8 hits the side surface 10a of the valve rubber 10, and this portion is also closed, resulting in the state shown in FIG. In addition, it is comprised by the step part 8b for releasing the pressure of the primary side 17 to the secondary side 18 at the time of valve opening drive, the clearance gap between the internal diameter of the valve rubber 10, and the outer diameter of the plunger 8, the 2nd spring 13, etc. The mechanism is called a secondary valve . 9 to 11, the sub valve is denoted by reference numeral 20.
[0006]
[Problems to be solved by the invention]
In the prior art, when the valve is closed, the valve rubber 10 is pressed against the flat seat surface of the valve seat 2 by the valve frame 11 and compressed in the thickness direction of the valve rubber 10. In order to prevent valve leakage, a certain amount of valve load is applied to ensure sealing performance. Therefore, when opening the valve, an electromagnetic force that overcomes the valve load is required, and the drive power of the solenoid valve increases. There was a problem.
[0007]
Moreover, the valve load of the current household gas meter requires 1 g / mm or more with respect to the circumference of the valve seat in order to prevent leakage, and if the drive power at the time of valve opening is reduced, the valve load is There was a problem that the valve seat sealing performance deteriorates because it is 1 g / mm or less with respect to the circumferential length of the valve seat. Actually, in the prior art having a valve rubber diameter of φ30, the load due to the primary and secondary pressure difference was about 150 g, and the load of the first spring was about 100 g.
[0008]
Accordingly, an object of the present invention is to provide a bidirectional shut-off valve for a gas meter that can eliminate such problems.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, according to the invention of claim 1, a lip-shaped portion that is bent and deformed by a load at the time of closing the valve rubber is formed on the peripheral edge of the valve rubber, and the peripheral lip-shaped portion of the valve rubber has a U-shaped cross section. A bidirectional shutoff valve for a gas meter, characterized in that it is formed .
[0012]
According to a second aspect of the present invention, in the bidirectional shutoff valve for a gas meter according to the first aspect, in a ring-shaped grounding portion formed by the valve rubber grounding on the valve seat surface of the valve seat, the grounding area is small in a part in the circumferential direction. A portion having a small ground contact area is formed.
[0013]
According to a third aspect of the present invention, in the bidirectional shutoff valve for a gas meter according to the first aspect, the radial width of the annular grounding portion generated by the contact of the valve rubber with the valve seat surface of the valve seat is reduced in a part of the circumference. It is characterized by that.
[0014]
The invention of claim 4 forms a lip-like portion that is bent and deformed by the load at the time of valve closing on the periphery of the valve rubber,
By forming a notch portion formed of an inclined surface in a part of the inner periphery of the valve seat surface, a ring-shaped grounding portion that is generated when the valve rubber contacts the valve seat surface of the valve seat in a circumferential direction. Form a part with a small ground contact area in a small part,
The gas rubber bidirectional shut-off valve for the gas meter , wherein the valve rubber is formed in a curved shape that curves inwardly from the grounding portion and opposite to the valve seat surface .
The invention of claim 5 forms a lip-shaped portion that is bent and deformed by the load at the time of valve closing on the periphery of the valve rubber,
By forming a notched portion formed of an inclined surface in a part of the inner periphery of the valve seat surface, the radial width of the annular grounding portion generated when the valve rubber contacts the valve seat surface of the valve seat is increased. Make it smaller in part of the circumference,
The gas rubber bidirectional shut-off valve for the gas meter, wherein the valve rubber is formed in a curved shape that curves inwardly from the grounding portion and opposite to the valve seat surface.
A sixth aspect of the invention is the gas meter bidirectional shutoff valve according to the second or third aspect, characterized in that a notch portion formed of an inclined surface is formed on a part of the valve seat surface, particularly on the inner periphery. It is.
[0015]
The invention of claim 7 forms a lip-shaped portion that is bent and deformed by the load at the time of valve closing on the periphery of the valve rubber,
In the ring-shaped grounding part formed by forming a notch in part of the outer periphery of the valve rubber and the valve rubber grounding on the valve seat surface of the valve seat, the grounding area is small in a part of the circumferential direction. A bidirectional shutoff valve for a gas meter, characterized in that a portion is formed .
The invention of claim 8 forms a lip-shaped portion that is bent and deformed by the load at the time of valve closing on the periphery of the valve rubber,
A notch is formed in a part of the outer periphery of the valve rubber, and the radial width of the annular grounding part that is generated when the valve rubber contacts the valve seat surface of the valve seat is reduced in a part of the circumference. This is a bidirectional shut-off valve for a gas meter.
A ninth aspect of the present invention is the gas meter bidirectional shutoff valve according to the second or third aspect, wherein a notch is formed in a part of the outer periphery of the valve rubber.
[0016]
A tenth aspect of the present invention is the gas meter bidirectional shutoff valve according to any one of the first to ninth aspects, further comprising a sub-valve for releasing the gas pressure from the primary side to the secondary side during the valve opening operation. Is.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Next, preferred embodiments of the present invention will be described according to some examples.
[0018]
[Example 1]
In Example 1 of FIG. 1, the valve rubber 10A is fitted to the left end portion of the plunger 8A as shown in the figure while being fitted to the valve frame 11A, and is attached by a washer 21 and an E ring 22 so as not to be detached from the plunger 8A. . The load of the spring 12A for urging the valve rubber 10A in the valve closing direction is smaller than the load of the first spring 12 shown in FIG. 9 described in the prior art. The valve seat 2A is configured by fitting a valve seat formed as a separate body to the shut-off valve mounting portion 1A constituting a part of the upper case of the gas meter. By doing so, compared to the case of FIG. 9 in which the valve seat is formed directly and integrally with the shut-off valve mounting portion, the processing accuracy of the flatness of the seat surface of the valve seat can be easily obtained, and the valve load is reduced accordingly. Also improves the sealing performance when the valve is closed.
[0019]
The valve rubber 10A is made of NBR, and its peripheral part is formed in a thin lip shape of about 0.3 to 1 mm. When the valve rubber 10A is pressed against the valve seat 2A by the load of the spring 12A and the pressure difference, the valve rubber 10A flexes flexibly. As shown in the figure, the gas is reliably sealed in close contact with the seat surface of the valve seat 2A. A gap 23 is formed between the valve rubber 10A and the valve frame 11A so that the valve rubber 10A can be easily bent in the axial direction (left-right direction in the drawing) of the plunger 8A regardless of the presence of the valve frame 11A.
[0020]
As shown in FIG. 2, the valve seat 2 </ b> A has a notch formed by an inclined surface 2 c on a part of the circumference so as to cover the flat seat surface 2 a and the inner periphery 2 b. In this way, a portion 2d having a small grounding area is formed as a grounding portion where the valve rubber 10A is in contact with the seating surface 2a to seal the gas. In other words, the width ΔR in the radial direction of the seat surface 2a is a small width Δr due to the presence of the notch portion by the inclined surface 2c. By doing so, the pressure difference applied to the valve rubber when the valve is closed is smaller in the portion 2d than in the other portions. Therefore, when the valve opening operation is started from the valve closed state, the valve rubber 10A around the portion 2d partially floats or the lip-shaped portion is deformed to open first and the primary and secondary pressures are opened. The same pressure makes it easier to open the valve. In other words, it opens lightly. In order to obtain such an action, instead of forming a notch portion by an inclined surface in a part of the valve seat 2A, a notch is provided in a part of the outer periphery of the valve rubber, and as a result, the contact area of this part is reduced. (See also Example 3 described later).
[0021]
[Example 2]
Since the gist of the present invention is around the valve rubber and the valve seat of the bidirectional shut-off valve, some examples of the shapes of the valve rubber and the valve frame are shown in FIGS. 3 (a), 3 (b) and 3 (c). Shown in In these drawings, the shape of the central portion of the valve rubber and the valve frame, particularly the portion to be attached to the plunger (not shown) is shown in a simplified manner and is different from the actual one. FIG. 3A is an example of a crescent shape in which the cross section of the valve rubber 10B is thin. In this example, there is no valve frame. The entire valve rubber 10B including the lip-shaped peripheral portion is integrally formed of a thin plate made of NBR. The cross-sectional shape of the valve rubber 10B in this example is similar to that of the first embodiment shown in FIG. In FIG. 3B, the valve rubber 10C is composed of a thin NBR plate having a thickness of 0.3 to 1 mm including the lip-shaped peripheral edge, and the valve frame 11C is separated from the valve rubber 10C except for the central portion thereof. There is a gap 23c between them. In the example of FIG. 3 (c), the valve rubber 10C is the same as the example of FIG. 3 (b), but the valve frame 11D has a part of a spherical surface whose curvature is larger than that of the example of FIG. Only the peripheral edge of the valve frame 11D was in contact with the valve rubber 10C, and the other part was separated to provide a gap 23D between the two.
[0022]
Example 3
In Example 3 shown in FIG. 4A, the valve seat 2 is formed integrally with the shutoff valve mounting portion 1A constituting a part of the upper case of the gas meter. The flat valve seat surface 2a of the valve seat 2 cooperates with a valve rubber 10C made of a thin plate made of NBR having a thickness of 0.3 to 1 mm.
[0023]
When a drive current is temporarily passed through the coil of the electromagnetic drive unit EM of the shut-off valve and the plunger 8A is moved to the left in the figure by the load of the spring 12A, the valve rubber 10C moves to the position of 10C ', and its lip shape Of the valve seat 2 is in pressure contact with the valve seat surface 2 a of the valve seat 2. At this time, the lip-shaped peripheral edge flexes flexibly and comes into close contact with the valve seat surface 2a to securely seal the gas. In this embodiment, as shown in FIG. 5B, a notch K is provided on the outer periphery of the valve rubber, so that a portion 2d 'having a small contact area is provided on the valve seat surface 2a at the annular portion where the valve rubber 10C contacts the ground. Thus, as in the case of Example 1 in FIGS. 1 and 2, the valve rubber is easily separated from the valve seat surface during the valve opening operation, thereby reducing power consumption during valve opening.
[0024]
In addition, as shown with the code | symbol 20, you may make it provide a subvalve similar to the case of the prior art of FIG.
[0025]
Example 4
Since Example 4 shown in FIG. 5 differs from Example 3 in FIG. 4 in the shape of the valve seat surface and the shape of the valve rubber, these parts will be described and the same parts as Example 3 will be described. Are denoted by the same reference numerals and description thereof is omitted. In this embodiment, a lip-shaped portion 10e having a U-shaped cross section is formed on the peripheral portion of the valve rubber 10C in FIG. 4 to constitute the valve rubber 10E, and the inner peripheral wall 2e of the valve seat 2 is also used as a sealing surface. Reference numeral 10E ′ is a valve rubber at the time of closing the valve, and its peripheral portion is in close contact with the valve seat surface 2e to seal the gas. In this embodiment, a sub valve may be provided as indicated by reference numeral 20. In the fourth embodiment, since the lip-shaped portion 10e at the peripheral edge of the valve rubber has a U-shaped cross section, the seal area can be increased in a small space, the outer diameter of the valve seat surface 2e can be reduced, and the valve can be downsized. Therefore, the inner diameter ΦN of the primary side 17 can be reduced as compared with the third embodiment of FIG. Further, there is an advantage that the molding of the valve rubber has a greater dimensional freedom than the shape of the third embodiment.
[0026]
Example 5
Since the fifth embodiment shown in FIG. 6 differs from the first embodiment in FIG. 1 only in the shape of the valve seat and the shape of the valve rubber, the same parts as those in the first embodiment are denoted by the same reference numerals. Description is omitted. In this embodiment, the valve seat 2B has an annular protrusion 2f having a diameter φ on its seat surface, and when the valve is closed, the valve rubber 10F is pressed against the annular protrusion 2f as shown in the figure to seal the gas. . At this time, the center of the valve rubber 10F, that is, the portion from the axis of the plunger 8A to the distance φ / 2 is flexibly deformed and is tightly sealed to the annular protrusion 2f. Φ is an outer diameter of the valve rubber and is determined to be larger than the diameter φ.
[0027]
Example 6
In Example 6 of FIG. 7, an annular protrusion 2f similar to the embodiment of FIG. 6 has a valve rubber 10C made of a thin thin plate made of NBR having a thickness of 0.3 to 1 mm and a diameter φ of the annular protrusion 2f. The outer periphery of the spherical valve frame 11C forms a structure around the seal portion. In FIG. 7, plungers and springs that are actually used are omitted from illustration. In this embodiment as well, the lip-shaped peripheral edge of the valve rubber flexes flexibly and adheres tightly to the valve seat surface 2f to seal the gas in the same manner as in the other embodiments. To prevent.
[0028]
[Classification of Seal Structure in Examples]
The seal structures of some of the above embodiments are classified and shown in FIG. In the same figure, (a) is a valve rubber 10C made of NBR having a peripheral edge formed in a lip shape and disposed opposite to the flat valve seat surface 2a of the valve seat 2A, and a part of the circumference of the valve seat 2A. A notch portion formed of an inclined surface (slope) 2c is formed. In this example, the lip-shaped peripheral edge portion of the valve rubber 10C bends and adheres along the flat valve seat surface 2a to seal the gas. In FIG. 5B, the peripheral lip portion 10e of the NBR valve rubber 10E is formed in a U-shaped cross section, and the inner peripheral wall (valve seat surface) 2e of the valve seat 2 is used as a sealing surface. FIG. 5C shows a structure in which the inside of the spherical surface of the valve rubber 10C, which is entirely formed of a part of a spherical surface made of NBR, is in close contact with the annular protrusion 2f of the valve seat 2B. In addition, the figure (d) is a figure which shows the valve seat surface in the figure (a), and the code | symbol 24 shows the outer diameter of the valve rubber 10C. ΔR ′ is a radius difference which is half the diameter difference obtained by subtracting the diameter of the inner periphery 2b of the valve seat from the outer diameter of the valve rubber 10C, and the annular portion of the width ΔR ′ is formed on the valve seat surface 2a to the peripheral lip of the valve rubber. The ground portion becomes the grounding portion that is in close contact with the ground. In a part of the circumference, the width ΔR ′ is a small width Δr ′ due to the notch formed by the inclined surface 2c. 2d corresponds to a portion with a small ground contact area described in the first embodiment.
[0029]
In the embodiment of the present invention, even when the load of the spring 12A was reduced to 20 g, good sealing performance could be maintained, and gas leakage could be reliably prevented.
[0030]
【The invention's effect】
Since the bidirectional shut-off valve for a gas meter of the present invention is configured as described above, it is possible to ensure sealing performance with a small valve load, and as a result, it is possible to reduce the power when the valve is opened, which helps to reduce the power consumption of the gas meter. . Incidentally, since the valve rubber flexes flexibly and adheres to the valve seat surface flexibly, the sealing performance can be secured even if the valve load is reduced to 0.1 g / mm. In addition, in the invention of claim 2, in addition to this, the inner peripheral wall of the valve seat, which is in contact with the outer peripheral edge of the U-shaped section of the valve rubber, can also be used as a sealing surface, so that the outer diameter of the sealing surface of the valve seat can be reduced, and the valve is small become. Therefore, even when the structure of the gas meter is complicated and a space for the shut-off valve cannot be taken, the ground contact area can be increased in a small space. In addition, the degree of freedom of molding dimensions of the valve rubber is great.
[0031]
According to the second to ninth aspects of the present invention, a part of the circumference of the valve rubber is easily separated from the valve seat surface at the time of the valve opening operation, and the power at the time of valve opening can be further reduced accordingly.
[0032]
In the invention of claim 10 , since the valve load due to the gas differential pressure is eliminated by the action of the sub-valve during the valve opening operation, the power at the time of valve opening can be further reduced.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of an embodiment of the present invention.
FIG. 2 is a perspective view of the valve seat of the embodiment of FIG.
FIG. 3 is a longitudinal sectional view for explaining a combination of different shapes of a valve rubber and a valve frame according to an embodiment of the present invention.
4A is a partial longitudinal cross-sectional view of the whole of the embodiment of the present invention, and FIG. 4B is a view of the valve rubber as viewed from the right side of FIG.
FIG. 5 is a partial longitudinal sectional view of an embodiment of the present invention.
FIG. 6 is a longitudinal sectional view of an embodiment of the present invention.
FIG. 7 is a longitudinal sectional view of an essential part of an embodiment of the present invention.
FIGS. 8A and 8B are diagrams showing a seal structure according to an embodiment of the present invention, wherein FIGS. 8A, 5B, and 8C are longitudinal sectional views, and FIG. 8D is a view of the valve seat of FIG. Figure.
FIG. 9 is a longitudinal sectional view of the prior art.
FIG. 10 is a longitudinal sectional view of a different aspect of the prior art.
FIG. 11 is a longitudinal sectional view of a different aspect of the prior art.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Shut-off valve attaching part 2,2A Valve seat 2a Valve seat surface 2b Inner circumference 2c Inclined surface 2d, 2d A part with small contact area 2e Inner circumference wall (valve seat surface)
2f Annular ridges ΔR, ΔR ′, Δr, Δr ′ Radial width 10A. 10B, 10C, 10E, 10F Valve rubber 20 secondary valve

Claims

弁ゴムの周縁に、閉弁時の荷重で撓み変形するリップ状部分を形成し、該弁ゴムの周縁リップ状部分を断面Ｕ字形に形成したことを特徴とするガスメータ用双方向遮断弁。A bidirectional shutoff valve for a gas meter, characterized in that a lip-shaped portion that is bent and deformed by a load at the time of closing the valve rubber is formed on the periphery of the valve rubber, and the peripheral lip-shaped portion of the valve rubber is formed in a U-shaped cross section .

弁座の弁座面に弁ゴムが接地して生じる環状の接地部において、円周方向の一部に接地面積が小さい接地面積小の部分を形成したことを特徴とする請求項１記載のガスメータ用双方向遮断弁。In an annular ground portion caused by grounding the valve rubber valve seat surface of the valve seat, according to claim 1, characterized by forming part of the ground contact area is small contact area small part of the circumferential gas meter For bidirectional shut-off valve.

弁座の弁座面に弁ゴムが接地して生じる環状の接地部の半径方向の幅を円周の一部において小さくしたことを特徴とする請求項１記載のガスメータ用双方向遮断弁。Gas meter for bidirectional shut-off valve according to claim 1, wherein the valve rubber valve seat surface of the valve seat is smaller in radial width of the circumference of a part of the ground portion of the annular resulting grounded.

弁ゴムの周縁に、閉弁時の荷重で撓み変形するリップ状部分を形成し、
弁座面の内周にかかる部分の一部に傾斜面からなる切欠部を形成することにより、弁座の弁座面に前記弁ゴムが接地して生じる環状の接地部において、円周方向の一部に接地面積が小さい接地面積小の部分を形成し、
前記弁ゴムにおける、前記接地部分より内側を、弁座面とは反対側に湾曲する湾曲状に形成したことを特徴とするガスメータ用双方向遮断弁。 A lip-shaped part that bends and deforms with the load at the time of valve closing is formed on the periphery of the valve rubber,
By forming a notch portion formed of an inclined surface in a part of the inner periphery of the valve seat surface, a ring-shaped grounding portion that is generated when the valve rubber contacts the valve seat surface of the valve seat in a circumferential direction. Form a part with a small ground contact area in a small part,
A bidirectional shut-off valve for a gas meter , wherein the valve rubber is formed in a curved shape that curves inwardly from the ground contact portion and opposite to the valve seat surface .

弁ゴムの周縁に、閉弁時の荷重で撓み変形するリップ状部分を形成し、
弁座面の内周にかかる部分の一部に傾斜面からなる切欠部を形成することにより、弁座の弁座面に前記弁ゴムが接地して生じる環状の接地部の半径方向の幅を円周の一部において小さくし、
前記弁ゴムにおける、前記接地部分より内側を、弁座面とは反対側に湾曲する湾曲状に形成したことを特徴とするガスメータ用双方向遮断弁。 On the periphery of the valve rubber, a lip-shaped part that is bent and deformed by the load at the time of valve closing is formed,
By forming a notched portion formed of an inclined surface in a part of the inner periphery of the valve seat surface, the radial width of the annular grounding portion generated when the valve rubber contacts the valve seat surface of the valve seat is increased. Make it smaller in part of the circumference,
A bidirectional shut-off valve for a gas meter , wherein the valve rubber is formed in a curved shape that curves inwardly from the ground contact portion and opposite to the valve seat surface .

弁座面の一部、特に内周にかかる部分に傾斜面からなる切欠部を形成したことを特徴とする請求項２又は３記載のガスメータ用双方向遮断弁。The bidirectional shutoff valve for a gas meter according to claim 2 or 3, wherein a notch portion formed of an inclined surface is formed in a part of the valve seat surface, in particular, a portion on the inner periphery.

弁ゴムの周縁に、閉弁時の荷重で撓み変形するリップ状部分を形成し、
弁ゴムの外周の一部に切欠部を形成して、弁座の弁座面に弁ゴムが接地して生じる環状の接地部において、円周方向の一部に接地面積が小さい接地面積小の部分を形成したことを特徴とするガスメータ用双方向遮断弁。 A lip-shaped part that bends and deforms with the load at the time of valve closing is formed on the periphery of the valve rubber,
In the ring-shaped grounding part formed by forming a notch in part of the outer periphery of the valve rubber and the valve rubber grounding on the valve seat surface of the valve seat, the grounding area is small in a part of the circumferential direction. A bidirectional shut-off valve for a gas meter, characterized in that a part is formed .

弁ゴムの周縁に、閉弁時の荷重で撓み変形するリップ状部分を形成し、
弁ゴムの外周の一部に切欠部を形成して、弁座の弁座面に弁ゴムが接地して生じる環状の接地部の半径方向の幅を円周の一部において小さくしたことを特徴とするガスメータ用双方向遮断弁。 A lip-shaped part that bends and deforms with the load at the time of valve closing is formed on the periphery of the valve rubber,
A notch is formed in a part of the outer periphery of the valve rubber, and the radial width of the annular grounding part that is generated when the valve rubber contacts the valve seat surface of the valve seat is reduced in a part of the circumference. Bidirectional shut-off valve for gas meter.

弁ゴムの外周の一部に切欠部を形成したことを特徴とする請求項２又は３記載のガスメータ用双方向遮断弁。The bidirectional shutoff valve for a gas meter according to claim 2 or 3 , wherein a notch is formed in a part of the outer periphery of the valve rubber.

開弁動作時に１次側から２次側へガス圧を抜く副弁を備えたことを特徴とする請求項１〜９のいずれかに記載のガスメータ用双方向遮断弁。The bidirectional shut-off valve for a gas meter according to any one of claims 1 to 9 , further comprising a sub-valve for releasing the gas pressure from the primary side to the secondary side during the valve opening operation.