JP4626051B2

JP4626051B2 - Shut-off valve

Info

Publication number: JP4626051B2
Application number: JP2000381880A
Authority: JP
Inventors: 正樹山口; 行則尾崎
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2000-12-15
Filing date: 2000-12-15
Publication date: 2011-02-02
Anticipated expiration: 2020-12-15
Also published as: JP2002181218A

Description

【０００１】
【発明の属する技術分野】
本発明は、外部状況によって作動する安全弁で操作手段として電動機を使用したもの、特に、ガスの事故を未然に防ぐガス遮断装置の遮断機構として使用される遮断弁に関し、さらに詳しくは流路に形成された弁座に対し弁体を前進または後退移動させることによって流路の遮断復帰動作を行うモータを動力源とした遮断弁に関するものである。
【０００２】
【従来の技術】
ガス事故を未然に防ぐため、従来より種種の安全装置が利用されており、中でもガスメータに内蔵され流量センサによりガスの流量を監視しマイクロコンピュータによりガスの使用状態を異常使用と判断した場合や、地震センサ、ガス圧力センサ、ガス警報器、一酸化炭素センサなどのセンサの状況を監視し危険状態と判断した場合は、ガスメータに内蔵された遮断弁によりガスを遮断する電池電源によるマイクロコンピュータ搭載ガス遮断装置内蔵ガスメータ（以下マイコンメータと省略する）は、安全性、ガス配管の容易性、低価格等の優位性のため、普及が促進され、近年ほぼ全世帯普及が実施されるに至っている。
【０００３】
また、流量センサによって計測されたガス流量情報を電話回線などを利用して集中監視するテレメータ機能を有した、集中監視型マイコンメータの比率も増加し、ますます、情報端末として利便性の向上が求められている。この集中監視型マイコンメータなどにおいては、簡単な電気スイッチ操作や電話回線などによる遠隔操作でガスの遮断、復帰が可能なよう、マイコンメータに搭載した電池による電気エネルギーでガス遮断もガス復帰も可能で開弁状態と閉弁状態の保持はエネルギーを必要としない遮断弁が要求されている。
【０００４】
この遮断弁の駆動方式としては、従来電磁ソレノイドを使用したものが主流であったが、近年比較的強い閉止力、復帰力を実現でき、非通電時は状態保持可能なＰＭ型ステッピングモータを駆動源とする遮断弁が注目されており、なかでもロータをガス流路内、ステータをガス流路外とする気密隔壁を持った遮断弁が、ガス流路への取り付けが容易なため主流である。
【０００５】
以下に従来の遮断弁について説明する。
【０００６】
従来のこの種の遮断弁は、特開平１１−３０３５６号公報に示すようなものが紹介されている。この特開平１１−３０３５６号公報記載の遮断弁は図４に示されているように、外周部に永久磁石による磁極２を有するロータ１と、励磁コイル４を囲み磁性材料で形成したステータ３と、ロータ１に設けたロータ回転軸５と、ロータ回転軸５の外周部に設けられた雄ねじである送り手段６と、送り手段６に螺合する雌ねじを設けた移動体７と、移動体７がロータ回転軸５に対して回転しないようにする回動防止体８と、移動体７に対して軸方向に移動可能に連結され流体通路２２中の流体の流動状態を規制する弁体９と、移動体７と弁体９の間に介在させ軸方向に互いに離れようとする付勢力を加える付勢体１０とで遮断弁が構成されている。弁体９は弁座２１に当接する弁ゴム板９ａを弁ゴム保持部９ｂに取り付けるとともに弁ゴム押え９ｃで固定して形成されている。１１は流体側にあるロータ１およびそれに連なる弁体９側とステータ３側とを気密に分離する隔壁であり、１２は隔壁１１およびステータ３を取付けた取付体であり、この取付体１２にはロータ回転軸５が貫通する貫通孔１２ａが設けられている。１３は隔壁１１のフランジ部と取付体１２の間に設け気密シールするＯリング、１４は流体通路２２と取付体１２の間を気密シールするＯリングである。
【０００７】
図５はこの従来の発明の弁体９近傍の断面部分図である。１５は移動体７に設けた外周方向に延びる外周突起７ａと弁体９の弁ゴム保持部９ｂに設けた内周方向に延びる内周突起９ｄとを嵌め合わせて係止した係止部であり、外周突起７ａは弁体９の内周壁９ｅとガタ（隙間）を設けるように形成され、内周突起９ｄは移動体７の外周壁７ｂとガタ（隙間）を設けるように形成されている。
【０００８】
以上のように構成された遮断弁について、以下その動作について説明する。
【０００９】
まずステータ３の励磁コイル４に接続した駆動回路により弁閉する方向に励磁コイル４に順次通電してロータ１の磁極に電磁力を加えてロータ１を回転させ、ロータ回転軸５に螺合した移動体７に力を加える。移動体７は回動防止体８により回り止めされているためロータ回転軸５の回転とともに弁座２１の方へ移動する。この時移動体７に連結された弁体９は移動体７とともに弁座２１の方へ移動し、この移動途中において付勢体１０の付勢力はロータ１の回転力に対して負荷とはならない。しかし、弁体９が弁座２１に当接すると付勢体１０の付勢力がロータ１に負荷として作用し、ロータ１の回転力は付勢体１０をあと僅かな寸法だけ圧縮させるよう移動体７を弁座２１の方へ移動させる。付勢体１０をあと僅かだけ圧縮してロータ１の回転を停止させると、弁体９を弁座２１に対して押し付けるように付勢体１０の付勢力が加わり、安定した弁閉止力が加わった状態で弁閉される。
【００１０】
次に、弁体９を弁座２１から離して開弁する方向に移動させる場合は、ロータ１の回転方向が逆転方向になるように駆動回路を切換えて駆動する。開弁動作において付勢体１０の付勢力が弁座２１に加わっている過程では、この付勢力がロータ１を開弁方向に回転させる力として作用するためロータ１を回転させる負荷が低減される。特に、弁閉時に流体の圧力差が弁座２１の上流、下流間に生じて図中の弁体９側が高い圧力となっている場合は、弁体９を弁座２１に押付ける力（背圧）として作用するが、付勢体１０の付勢力はこの背圧を低減する方向に作用するため開弁時の負荷が低減される。弁体９が弁座２１から離れると付勢体１０の付勢力はロータ１の負荷とは無関係となり、ロータ１の回転により弁体９を開弁位置まで移動させて駆動回路によりロータ１の回転を停止する。
【００１１】
このように、付勢体１０を配することによって、安定した弁閉止力と、開弁時の負荷低減が実現できる技術が公開されている。
【００１２】
【発明が解決しようとする課題】
この種の遮断弁は、一般的に屋外に設置されるガスメータに取り付けられ、夏の直射日光下での５０℃を超過する温度から、厳冬期の−２０℃を下回る温度までの厳しい温度変化にさらされることになる。このような環境下で、ガスメータの使用期間（一般に１０年間）中破壊しない構造強度と、マイコンメーターのマイクロコンピュータがガスの使用状態を異常使用と判断した場合や、地震センサ、ガス圧力センサ、ガス警報器、一酸化炭素センサなどのセンサの状況を監視し危険状態と判断した場合は、ガスを確実に遮断できる高い信頼性が要求されている。
【００１３】
上記のような構造の遮断弁においては、移動体７や弁体９の弁ゴム押保持部９ｂ、内周突起９ｄ、内周壁９ｅを一体構成する部材は、形状の複雑さより材料としては通常合成樹脂が選択される。合成樹脂は長期間応力を受け続けると、応力緩和するようにクリープ変形するという特性を有している。一方、マイコンメータの遮断弁としてこの種の遮断弁が使用される場合は、通常開弁状態であるため、係止部１５に付勢体１０の反力が常時印加され、移動体７の外周突起７ａや弁体９の内周突起９ｄに応力が印加された状態がガスメータの使用期間のほぼ大半継続することになる。したがって、この種の移動体７と弁体９との間に付勢体１０を配した遮断弁においては、付勢体１０の反力による外週突起７ａと内周突起９ｄのクリープ変形を少量にとどめ、その使用期間において係止部１５が充分な構造強度を有し、付勢体１０の動作を妨げることなくガスを遮断できる信頼性が確保されなければならない。
【００１４】
しかしながら、上記の従来の遮断弁では、内周壁９ｅが外側に広がるクリープ変形を防止する手段がなく、長期間付勢体１０の反力を受け続けることによって、係合部１５が外れ弁体９が弁座２１に当接できなくなってガスを遮断できなくなる可能性があった。さらに、この遮断弁のような構成の場合、組立可能にするために弁体９の内周突起９ｄおよび内周壁９ｅにいたる縦割り溝が形成されることが一般的であり、この場合内周壁９ｅの強度がさらに低下するだけでなく、図５に示したように、弁体９がガスの動圧などによって偏心荷重Ｐを受け角度θ傾いた場合、縦割り溝幅が拡大しより係合部１５が外れやすくなるといった課題を有していた。
【００１５】
また、上記の従来の遮断弁では、弁ゴム板９ａは中央に穴を有し、その穴に弁ゴム保持部９ｂを圧入することで弁ゴム板９ａと弁ゴム保持部９ｂを気密に保持し、さらに弁ゴム押え９ｃを弁ゴム保持部９ｂの先端突起に圧入することで構造を保持しているが、この弁ゴム押え９ｃと弁ゴム保持部９ｂの先端突起の圧入部も使用期間においてクリープ変形し弁ゴム押え９ｃが抜け落ち、弁ゴム板９ａと弁ゴム保持部９ｂとの気密構造を維持できなくなる可能性があるという課題があった。加えて、弁ゴム保持部９ｂは、低分子炭化水素である燃料用ガスや、ガス中に微少に含まれる水分、硫化水素、二酸化硫黄などの精製不純物である活性ガスなどの有機物雰囲気および弁ゴム板９ａを構成する合成ゴムに含まれる可塑剤など浸透性の高い有機化合物と接しながら厳しい温度変化にさらされることで、材料樹脂にマイクロクラック、更に大きなストレスクラックが発生し、弁ゴム板９ａと弁ゴム保持部９ｂとの気密が破壊されたり、弁ゴム保持部９ｂ自身から漏れが発生する可能性があるといった課題があった。
【００１６】
また、上記の遮断弁を駆動する遮断弁装置は、弁体９が弁座２１に当接すると付勢体１０をあと僅かだけ圧縮してロータ１の回転が停止するため、部品や組み立てのばらつきによる閉弁ストロークばらつきを吸収できず、閉弁動作中の過負荷による閉弁信号の読み飛ばしや、閉弁後の外部衝撃による弛み等によって閉弁ストローク不足になり、ガス遮断信頼性が低下する可能性があるといった課題があった。
【００１７】
本発明はかかる従来の課題に鑑み、偏心荷重や長期使用における温度ストレス等によって弁体と移動体との係合部が外れにくく、充分な構造強度を有し、また有機化合物等のアタックで弁ゴム保持部材にクラックが生じた場合でもガスを遮断可能な、高い気密信頼性を有した遮断弁を提供することを目的とする。
【００１８】
また、閉弁動作中の過負荷による閉弁信号の読み飛ばしや、閉弁後の外部衝撃による弛み等が発生した場合でも閉弁ストローク不足になりにくい、高いガス遮断信頼性を有する遮断弁装置を提供することを目的とする。
【００１９】
【課題を解決するための手段】
本発明は上記課題を解決するために、未通電で回転位置を保持可能な電動回転機構と、前記電動回転機構の回転軸に配された送り手段と、中心孔が前記送り手段に螺合あるいは係合可能で前記電動回転駆動機構側に概ね円盤状のバネ受けを形成され他端に径の太い係合リング部を形成されそれらの間に外径の細い円筒部を形成された移動体と、流路内に形成された弁座に当接可能な概ね円盤状の弁シートと、おおむね円盤状に形成され一端に前記弁シートを保持し、他端に前記電動回転機構側に突出する内径が前記移動体の係合リング部外径とほぼ等しく軸方向に縦割りが形成された円筒部を有し、この円筒部の端に内径が前記移動体の係合リング部外径より細く前記移動体の円筒部外径とほぼ等しい内側に突出した係合爪を形成され、前記移動体と係合して保持された弁シート保持部材と、前記移動体と前記弁シート保持部材との間に圧縮して保持され内径が前記弁シート保持部材の円筒部外径とほぼ等しいコイルスプリングとで遮断弁を構成したものである。
【００２０】
上記のように、移動体と弁シート保持部材との係合部の外側に、内径が前記弁シート保持部材の円筒部外径とほぼ等しいコイルスプリングを配したため、前記円筒部がクリープ変形や偏心荷重などで外側に広がることを規制し、偏心荷重や長期使用における温度ストレス等によって弁シート保持部材と移動体との係合部が外れにくく、充分な構造強度を有している。
【００２１】
【発明の実施の形態】
本発明の遮断弁は、未通電で回転位置を保持可能な電動回転機構と、前記電動回転機構の回転軸に配設された送り手段と、前記送り手段に螺合あるいは係合可能な中心孔を有し、前記送り手段が挿入される端部から円盤状のバネ受けと外径の細い円筒部とこの円筒部より外径の太い係合リング部を順に形成した移動体と、流路内に形成した弁座に当接可能な弁シートと、一端に前記弁シートを保持し、他端に前記電動回転機構側に突出する内径が前記移動体の係合リング部の外径とほぼ等しく軸方向に縦割りが形成された円筒部を有し、この円筒部の端に内径が前記移動体の係合リング部の外径より細く前記移動体の円筒部の外径とほぼ等しい内側に突出した係合爪を形成し、前記移動体と係合して保持される弁シート保持部材と、前記移動体と前記弁シート保持部材との間に圧縮して保持され、内径が前記弁シート保持部材の円筒部の外径とほぼ等しいコイルスプリングとで構成されたものである。
【００２２】
そして、移動体と弁シート保持部材との係合部の外側に、内径が前記弁シート保持部材の円筒部外径とほぼ等しいコイルスプリングを配したため、前記円筒部がクリープ変形や偏心荷重などで外側に広がることを規制し、偏心荷重や長期使用における温度ストレス等によって弁シート保持部材と移動体との係合部が外れにくく、充分な構造強度を有するすぐれた遮断弁を提供することができる。
【００２３】
また、本発明の遮断弁は、上記構成に加えて、弁シートが嵌通孔のない概ね円盤状で、外周に弁シート保持部材側に張り出しこの弁シート保持部材の外径より内径の小さい袋状の折り返し部を形成された可撓体製であることを特徴とするものである。
【００２４】
そして、弁シートの外周部に袋状の折り返し部を形成し、弁シート保持部材をこの折り返し部の内側に内蔵するように保持するため弁ゴム押えが不要で、弁ゴム押えの脱落による気密性の破壊がない。また、弁シートに貫通穴がないため、長期使用において有機物雰囲気中での温度ストレス等によって弁シート保持部材にクラックが発生した場合でも漏れに至らず、高い気密信頼性を有するすぐれた遮断弁を提供することができる。
【００２５】
また、本発明の遮断装置は、上記構成の遮断弁と、閉弁動作時に前記遮断弁の弁シートが弁座に当接しコイルスプリングが下死点まで圧縮された後もさらに若干多くの信号を出力する駆動手段で構成されたものである。
【００２６】
そして、閉弁動作時に前記遮断弁の弁シートが弁座に当接しコイルスプリングが下死点まで圧縮された後もさらに若干多くの信号を出力するため、閉弁動作中の過負荷による閉弁信号の読み飛ばしや、閉弁後の外部衝撃による弛み等が発生した場合でも閉弁ストローク不足になりにくい安定した遮断弁装置を提供することができる。
【００２７】
【実施例】
以下、本発明の実施例について図面を用いて説明する。
【００２８】
（実施例１）
図１、図２、図３はそれぞれ本発明の実施例１の遮断弁の開弁状態、遮断動作中、閉弁状態の断面図、図４は本発明の実施例１の遮断弁の取り付け板、ステータ、支持フレームの形状を示す斜視図である。
【００２９】
図１および図４において、概ね糸巻き状のコイルボビン４１に導線４２が巻線された励磁コイル４３と、外周に円筒部を有し内周に櫛歯状の磁極を持った第１の電磁ヨーク４４と、この電磁ヨーク４４との間で励磁コイル４３を挟持するように配された概ね円盤状で内周に櫛歯状の磁極を持った第２の電磁ヨーク４５とのセットが２組、互いの第２の電磁ヨーク４５の円盤部を接触させて配されステータ４６を形成している。コイルボビン４１は合成樹脂製でポリブチレンテレフタレート（ＰＢＴ）のような耐熱性があり電気絶縁性の良好なものが望ましい。第１の電磁ヨーク４４および第２の電磁ヨーク４５は、低炭素鋼板、電磁軟鉄板または硅素鋼板製などの鋼板製で、表面に亜鉛メッキやアルミニウムメッキ、クロム酸処理膜等の防錆処理を施されているか、もしくは電磁ステンレス鋼板製で、経済的には亜鉛メッキ鋼鈑などのプリメッキ鋼鈑が望ましい。第１の電磁ヨーク４４と第２の電磁ヨーク４５の櫛歯状の磁極は所定の隙間を持って噛合し、また２組のセットの櫛歯は、回転方向に他のセットの櫛歯のほぼ隙間部に位置するよう配置されている。
【００３０】
ステータ４６の内側に同軸に、２段の底４７ａ、４７ｂと、大小の円筒部４７ｃ、４７ｄ、大径の円筒部４７ｃの開放端につば４７ｅを有するなべ状に絞り成形された嵌通孔のない金属性の隔壁４７が配されている。隔壁４７の材料は、非磁性ステンレス鋼鈑、銅合金、アルミニウム合金、合成樹脂、セラミックスなどの剛体が選択可能であるが、耐腐食性、強度、耐クリープ、薄肉加工性などの理由から、オーステナイト系ステンレス鋼鈑を絞り加工したものが最適であり、絞り加工後固溶化熱処理を施し、残留する内部応力と結晶粒の微細化を除去したものが望ましい。
【００３１】
隔壁４７の小径の円筒部４７ｄなべ側面内側には、中心孔４８ａを有する合成樹脂製の第１の軸受４８が嵌挿されている。隔壁４７の円筒部４７ｄと第１の軸受４８は締まり嵌めで嵌合している。第１の軸受４８の嵌挿部４８ｂと中心孔４８ａとの間には、薄肉化した波紋状の応力緩和部４８ｃが形成されている。また、隔壁４７の底４７ａに当接するようストッパ４８ｄが形成されている。この第１の軸受４８の材料は、ポリアセタール（ＰＯＭ）、ポリアミド（ＰＡ）およびポリテトラフルオロエチレン（ＰＴＦＥ）粉末や黒鉛粒子を配合された各種合成樹脂などの、自己潤滑性を有する合成樹脂が選択可能であるが、摩擦係数の低さや経済的理由からポリアセタールが最適である。このポリアセタールは応力クリープが比較的大きく軟質であるため、締まり嵌めの嵌め合いを設定する場合は、比較的大きな締め代を設定する必要があり、例えば隔壁４７の円筒部４７ｄの内径が８ｍｍである場合は第１の軸受４８の嵌挿部４８ｂの外径は８．０５〜８．１ｍｍ程度が適切である。
【００３２】
隔壁４７の大径の円筒部４７ｃのなべ側面の開放端側には、第２の軸受け４９ａと、側面に中心軸と垂直な開放端４９ｇを持つ円筒部４９ｂと、外周につば部４９ｃとを同軸に有する合成樹脂製のふた４９が、つば部４９ｃを隔壁４７のつば４７ｅに当接して嵌挿されている。隔壁４７の円筒部４７ｃとふた４９の嵌挿部４９ｅは締まり嵌めで嵌合している。ふた４９の嵌挿部４９ｅと第２の軸受け４９ａとの間には、薄肉化した波紋状の応力緩和部４９ｄが形成されている。このふた４９の材料としては第１の軸受４８同様ポリアセタールが最適である。隔壁４７の円筒部４７ｃとふた４９の嵌挿部４９ｅとの締まり嵌めの嵌め合いは、後述する別の固定手段があるため、また円盤部４９ｆの波打ちを防止するために比較的ゆるめでよく、例えば隔壁４７の円筒部４７ｃの内径が１８ｍｍである場合はふた４９の嵌挿部４９ｅの外径は１８．０２〜１８．０８程度が適切である。ふた４９の円筒部４９ｂの内面には中心軸に平行な凸状のリブ５０が、円周上で１８０°離れた２カ所に形成されている。
【００３３】
隔壁４７の内側には、円周方向に分極着磁された円筒形の永久磁石５１と、一方の端に送りネジ５２を形成された回転軸５３と永久磁石５１と回転軸５３を同軸に保持するスリーブ５４とで構成されたロータ５５が、回転軸５３の送りネジ５２側端をふた４９の第２の軸受け４９ａに、逆の端を第１の軸受４８の中心孔４８ａに回転可能に緩挿されて配されている。
【００３４】
流体室５６に取り付け可能な取り付け板５７は、中央に中心孔５７ａと隔壁４７の大径の円筒部４７ｃの外径より若干大きな内径を持った円筒状段差部５７ｂを形成され、外周部の２カ所にかぎ爪状の嵌合部５７ｃを形成されている。段差部５７ｂには隔壁４７の大径の円筒部４７ｃの端部が挿入され、ふた４９の円筒部４９ｂが中心孔５７ａを貫通して流体室５６側に突出し、円筒部４７ｃの外周と段差部５７ｂの内周との間には、合成ゴム製Ｏリングなどの弾性体シール部材５８が隔壁４７の中心軸に対して円周方向に圧縮されて配されている。ふた４９のつば部４９ｃは、取り付け板５７の段差部５７ｂの底面５７ｄと隔壁４７のつば４７ｅとに挟まれて保持されている。
【００３５】
取り付け板５７のシール面５７ｅと流体室５６との間にはシール部材６９が圧縮されて保持されており、取り付け板５７と流体室５６間を気密に保持している。
【００３６】
取り付け板５７の隔壁４７側平面にはステータ４６が当接して配されていて、このステータ４６と隔壁４７を押しつけて取り付け板５７との間に挟み込んで、両端を取り付け板５７の嵌合部５７ｃに嵌合されて、概ねコの字形状の支持フレーム５９が配されている。支持フレーム５９にはステータ４６に係合可能な係合部５９ｂが形成され、ステータ４６の回転を防止している。なお、この例では係合部５９ｂは背面から見ると凸字形状であり、先端部を電磁ヨーク４４に開口した孔に差し込んで係合し、凸字の段差部で電磁ヨーク４４を取り付け板５７側へ付勢している。ステータ４６とシール部材５８との間には、シール部材５８が取り付け板５７の段差部５７ｂから脱落することを防止するバックアップリング６０が配されている。取り付け板５７、支持フレーム５９の材質は表面処理された鋼板、ステンレス鋼板、銅合金板、アルミニウム合金板など耐ガス性、耐腐食性と、強度を持った剛体材料であり、経済的理由から表面処理された鋼板が選択しやすい。
【００３７】
流体室５６内に配された移動体６１は、中心孔６１ａが回転軸５３の送りネジ５２に螺合し、ステータ４６側に概ね円盤状のバネ受け６１ｂを形成され、他端に径の太い係合リング部６１ｃを形成され、それらの間に径の細い円筒部６１ｄを形成されている。バネ受け６１ｂの外周には、ふた４９のリブ５０と係合可能な凹状部６１ｅが、円周上で９０°の間隔に４カ所に成形されている。この凹状部６１ｅがリブ５０と係合することで、移動体６１と軸受４９との回転が防止され、送りネジ５２の回転動作が移動体６１の前後動作に変換される。移動体６１の材料は、ポリアセタール（ＰＯＭ）、ポリアミド（ＰＡ）およびポリテトラフルオロエチレン（ＰＴＦＥ）粉末や黒鉛粒子を配合された各種合成樹脂などの、自己潤滑性を有する合成樹脂が選択可能であるが、摩擦係数の低さや経済的理由からポリアセタールが最適である。
【００３８】
弁体６２は、流体室５６内に形成された弁座６５に当接可能な概ね円盤状で合成ゴムなどの可撓体性の弁シート６３と、弁シート６３のステータ４６側の面に当接して配された合成樹脂など剛体製の弁シート保持部材６４とで構成されている。弁シート６３は貫通孔がない円盤状で、外周に弁シート保持部材６４側に張り出しこの弁シート保持部材６４の外径より内径の小さい袋状の折り返し部６３ａを形成し、弁シート保持部材６４を抱き込むようにして遊嵌している。弁シート保持部材６４は、ステータ４６側に突出し、内径が移動体６１の係合リング部６１ｃの外径とほぼ等しく軸方向に縦割り６４ａが形成された円筒部６４ｂを有し、この円筒部６４ｂの端に、内径が移動体６１の係合リング部６１ｃ外径より細く移動体６１の円筒部６１ｄ外径とほぼ等しい、内側に突出した係合爪６４ｃを有し、移動体６１と係合して配されている。弁シート保持部材６４の円筒部６４ｂ先端と移動体６１のバネ受け６１ｂとの間には隙間６９が設けられている。弁シート保持部材６４の材料は、ポリアセタール（ＰＯＭ）、ポリアミド（ＰＡ）、ポリブチレンテレフタレート（ＰＢＴ）といった、耐ガス性を有する合成樹脂材料が望ましい。
【００３９】
移動体６１と弁シート保持部材６４との間には、弁シート保持部材６４の円筒部６４ｂ外径とほぼ等しい内径を有するコイルスプリング６６が圧縮して保持されている。
【００４０】
そして、この移動体６１と弁体６２とで弁機構を構成しており、開弁側の移動下死点においてはふた４９の開放端４９ｇと、弁シート保持部材６４の裏面６４ｄが当接し、かつ、ふた４９と移動体６１の間には隙間を有するよう軸方向の長さを設定されている。
【００４１】
ロータ５５のスリーブ５４と第１の軸受４８、ふた４９との間には、ポリテトラフルオロエチレン（ＰＴＦＥ）や黒鉛粒子を配合したポリアミド（ＰＡ）などの自己潤滑性を有する合成樹脂製のスラストワッシャ６７、６８が配されている。
【００４２】
次にこの実施例１の遮断弁の動作、作用について説明する。
【００４３】
ガスの使用状態が異常でなく、各種センサーからの信号が危険を示していない時、マイコンメータの制御部（図示せず）からの通電はなく、遮断弁は図１に示したように移動体６１はステータ４６側にあり、弁体６２は弁座６５から離れた開弁状態を保持し、ガスが流通可能である。
【００４４】
ガスの使用状態が異常であるか、各種センサーからの信号が危険を示している時、マイコンメータの制御部駆動は駆動手段（図示せず）を介して励磁コイル４３の各導線４２に位相差を持ったパルス状電流を印加し、ロータ５５を正回転させる。移動体６１は凹状部６１ｅがリブ５０と係合し回転を防止されているため、ロータ５５に連動した送りネジ５２の回転動作は移動体６１の前後動作に変換され、移動体６１と係合している弁体６２は、弁シート６３が弁座６５に当接する位置に移動し、図２に示した状態になる。さらに移動体６１が弁座６５側に前進すると、コイルスプリング６６がより圧縮され、弁シート保持部材６４の円筒部６４ｂ先端と移動体６１のバネ受け６１ｂとが当接し、弁シート６３が撓み、圧縮され、ついに移動体６１の反発力が送りネジ５２の推力より大きくなり、ロータ５５の回転が停止する。制御手段はコイルスプリング６６下死点まで圧縮された後もさらに若干多くの信号を出力する。こうして、弁体６２は弁座６５にコイルスプリング６６で付勢され、ガスが遮断される。この閉弁状態の遮断弁を図３に示した。
【００４５】
この後、マイコンメータの制御部が通電を停止しても、ロータ５５は保持トルクのため状態を保持し、したがって弁体６２は弁座６５にコイルスプリング６６で付勢された閉弁状態を保持する。
【００４６】
各種センサーからの信号から危険が解除され復帰可能とマイコンメータの制御部が判断した場合や、ガス利用者が危険状態を復旧し、メータやリモートコントロール盤に設けられた復帰スイッチを操作した場合、ガス供給業者などが通信による遠隔復帰命令を発信した場合などには、マイコンメータの制御部は励磁コイル４３の各導線４２に逆位相差を持ったパルス状電流を印加し、ロータ５５を逆回転させる。すると送りネジ５２に送られて移動体６１はステータ４６側に移動し、弁体６２は弁座６５から離脱し、ガスが流通可能になる。移動体６１はさらにステータ４６側に移動し、ついに弁体６２の弁シート保持部材６４の裏面６４ｄがふた４９の円筒部４９ｂの開放端４９ｇに当接し移動下死点となってロータ５５の回転が停止する。この後マイコンメータの制御部が通電を停止しても、ロータ５５は保持トルクのため状態を保持し、図１に示した開弁状態を保持する。
【００４７】
さて、この種の遮断弁は、一般的に屋外に設置されるガスメータに取り付けられ、夏の直射日光下での５０℃を超過する温度から、厳冬期の−２０℃を下回る温度までの厳しい温度変化にさらされることになる。このような環境下で、ガスメータの使用期間（一般に１０年間）中破壊しない構造強度と、マイコンメーターのマイクロコンピュータがガスの使用状態を異常使用と判断した場合や、地震センサ、ガス圧力センサ、ガス警報器、一酸化炭素センサなどのセンサの状況を監視し危険状態と判断した場合は、ガスを確実に遮断できる高い信頼性が要求されている。
【００４８】
本実施例の遮断弁は、移動体６１と弁シート保持部材６４との係合部の外側、すなわち係合爪６４ｃの外側に、内径が弁シート保持部材６４の円筒部６４ｂ外径とほぼ等しいコイルスプリング６６を配したため、円筒部６４ｂがクリープ変形や偏心荷重などで外側に広がることを規制し、偏心荷重や長期使用における温度ストレス等によって弁シート保持部材６４と移動体６１との係合部が外れにくく、充分な構造強度を有するすぐれた遮断弁を提供することができる。
【００４９】
また、弁シート６３の外周部に袋状の折り返し部６３ａを形成し、弁シート保持部材６４をこの折り返し部６３ａの内側に内蔵するように保持するため弁ゴム押えが不要で、弁ゴム押えの脱落による気密性の破壊がない。また、弁シート６３に貫通穴がないため、長期使用において有機物雰囲気中での温度ストレス等によって弁シート保持部材６４にクラックが発生した場合でも漏れに至らず、高い気密信頼性を有するすぐれた遮断弁を提供することができる。
【００５０】
また、この遮断弁を駆動する駆動装置（図示せず）は、閉弁動作時に弁シート６３が弁座６５に当接しコイルスプリング６６が下死点まで圧縮された後もさらに若干多くの信号を出力するため、閉弁動作中の過負荷による閉弁信号の読み飛ばしや、閉弁後の外部衝撃による弛み等が発生した場合でも閉弁ストローク不足になりにくい安定した遮断弁装置を提供することができる。
【００５１】
なお、図１において、ふた４９にリブ５０を設け、移動体６１に凹状部６１ｅを設けるとしたが、第２の軸受に溝を設け、移動体に凸状部を設けて係合させ回転防止手段としてもよい。また、励磁コイル４３、第１の電磁ヨーク４４、第２の電磁ヨーク４５のセットは２セットとしたが、３セットでも、より多数でもよい。また、シール部材５８は径方向に圧縮されて配されるとしたが、軸方向の圧縮でも良い。ただし、この場合はふた４９のつば４９ｃがクリープ変形することによってシール部材５８の圧縮率が小さくなる可能性が大きいので、シール部材５８の軸方向の圧縮率を左右する部分にはつば４９ｃ等の合成樹脂を介在させないよう形成することが必要である。また、スラスト軸受は滑り軸受であるスラストワッシャ６７、６８としたが、ボールベアリングなどの転がり軸受でもよい。ただし、マイコンメータの遮断弁の場合は、長期間にわたって開弁静止状態で放置されることが多いため、潤滑油の使用は好ましくない。また、送り手段は送りねじとしたが円筒カムなどでもよい。また、送り手段と移動体は雄ネジと雌ネジとしたが、ウォームとラックの組み合わせでもよい。
【００５２】
弁シート６３は弁シート保持部材６４を抱き込んでいるとしたが、中央で嵌合してもよく、弁シート保持部材に中心軸を形成して弁シートを気密に貫通させ別の固定部材で締結してもよい。ただし、この場合は本発明の請求項２に記載された、弁ゴム押えの脱落による気密性の破壊がない効果や、長期使用において有機物雰囲気中での温度ストレス等によって弁シート保持部材にクラックが発生した場合でも漏れに至らない効果は実現できない。
【００５３】
【発明の効果】
以上の説明から明らかのように本発明の遮断弁によれば次の効果を奏する。
【００５４】
移動体と弁シート保持部材との係合部の外側に、内径が弁シート保持部材の円筒部外径とほぼ等しいコイルスプリングを配したため、円筒部がクリープ変形や偏心荷重などで外側に広がることを規制し、偏心荷重や長期使用における温度ストレス等によって弁シート保持部材と移動体との係合部が外れにくく、充分な構造強度を有するすぐれた遮断弁を提供することができる。
【００５５】
また、弁シートの外周部に袋状の折り返し部を形成し、弁シート保持部材をこの折り返し部の内側に内蔵するように保持するため弁ゴム押えが不要で、弁ゴム押えの脱落による気密性の破壊がない。また、弁シートに貫通穴がないため、長期使用において有機物雰囲気中での温度ストレス等によって弁シート保持部材にクラックが発生した場合でも漏れに至らず、高い気密信頼性を有するすぐれた遮断弁を提供することができる。
【００５６】
さらにまた、閉弁動作時に前記遮断弁の弁シートが弁座に当接しコイルスプリングが下死点まで圧縮された後もさらに若干多くの信号を出力するため、閉弁動作中の過負荷による閉弁信号の読み飛ばしや、閉弁後の外部衝撃による弛み等が発生した場合でも閉弁ストローク不足になりにくい安定した遮断弁装置を提供することができる。
【図面の簡単な説明】
【図１】本発明の実施例１の遮断弁の開弁状態の断面図
【図２】同遮断弁の遮断動作中の断面図
【図３】同遮断弁の閉弁状態の断面図
【図４】従来の遮断弁の開弁状態の断面図
【図５】同遮断弁の弁体近傍の断面図
【符号の説明】
４６ステータ（電動回転機構）
５５ロータ（電動回転機構）
５３回転軸
５２送りネジ（送り手段）
６１移動体
６１ｂバネ受け
６１ｃ係合リング部
６１ｄ円筒部
６３弁シート
６３ａ折り返し部
６４弁シート保持部材
６４ａ縦割り
６４ｂ円筒部
６４ｃ係合爪
６５弁座
６６コイルスプリング[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a safety valve that operates according to an external situation and uses an electric motor as an operation means, and more particularly to a shut-off valve used as a shut-off mechanism of a gas shut-off device that prevents a gas accident in advance. The present invention relates to a shutoff valve using a motor as a power source for performing a shutoff return operation of the flow path by moving the valve body forward or backward relative to the valve seat.
[0002]
[Prior art]
In order to prevent gas accidents, various types of safety devices have been used in the past.In particular, when the flow rate sensor built in the gas meter monitors the gas flow rate and the microcomputer determines that the gas usage status is abnormal, Microcomputer-equipped gas with a battery power source that shuts off the gas with a shut-off valve built in the gas meter when the status of sensors such as earthquake sensors, gas pressure sensors, gas alarms, carbon monoxide sensors, etc. The gas meter with built-in shut-off device (hereinafter abbreviated as microcomputer meter) has been promoted for its advantages such as safety, ease of gas piping, and low price, and in recent years, almost all households have become popular.
[0003]
In addition, the ratio of centralized monitoring micrometers that have a telemeter function that centrally monitors the gas flow rate information measured by the flow sensor using a telephone line will increase, and the convenience of information terminals will increase. It has been demanded. In this central monitoring type microcomputer meter, etc., gas can be shut off and restored by electric energy from the battery installed in the microcomputer meter so that gas can be shut off and restored by simple electric switch operation or remote operation by telephone line etc. On the other hand, a shut-off valve that does not require energy is required to maintain the open and closed states.
[0004]
As the drive system for this shut-off valve, the one that used an electromagnetic solenoid has been the mainstream. However, in recent years, a relatively strong closing force and return force can be realized. A shut-off valve with a gas-tight partition with the rotor inside the gas flow path and the stator outside the gas flow path is the mainstream because it is easy to attach to the gas flow path. .
[0005]
A conventional shut-off valve will be described below.
[0006]
As this type of conventional shut-off valve, the one shown in Japanese Patent Laid-Open No. 11-30356 has been introduced. As shown in FIG. 4, the shut-off valve described in Japanese Patent Application Laid-Open No. 11-30356 includes a rotor 1 having a magnetic pole 2 made of a permanent magnet on the outer periphery, a stator 3 enclosing an exciting coil 4 and formed of a magnetic material. The rotor rotating shaft 5 provided in the rotor 1, the feeding means 6 that is a male screw provided on the outer periphery of the rotor rotating shaft 5, the moving body 7 that is provided with the female screw that is screwed to the feeding means 6, and the moving body 7 Is prevented from rotating with respect to the rotor rotating shaft 5, and the valve body 9 is connected to the moving body 7 so as to be movable in the axial direction and regulates the flow state of the fluid in the fluid passage 22. The shutoff valve is constituted by an urging body 10 that is interposed between the moving body 7 and the valve body 9 and applies an urging force to be separated from each other in the axial direction. The valve body 9 is formed by attaching a valve rubber plate 9a contacting the valve seat 21 to the valve rubber holding portion 9b and fixing it with a valve rubber presser 9c. 11 is a partition that hermetically separates the rotor 1 on the fluid side and the valve body 9 side that is connected to the rotor 1 and the stator 3 side, and 12 is an attachment body to which the partition wall 11 and the stator 3 are attached. A through hole 12a through which the rotor rotating shaft 5 passes is provided. Reference numeral 13 denotes an O-ring which is provided between the flange portion of the partition wall 11 and the attachment body 12 and seals the airtightly. Reference numeral 14 denotes an O-ring which airtightly seals between the fluid passage 22 and the attachment body 12.
[0007]
FIG. 5 is a partial sectional view of the vicinity of the valve body 9 of the conventional invention. Reference numeral 15 denotes a locking portion that fits and locks an outer peripheral protrusion 7 a provided on the movable body 7 extending in the outer peripheral direction and an inner peripheral protrusion 9 d provided on the valve rubber holding portion 9 b of the valve body 9 extending in the inner peripheral direction. The outer peripheral projection 7a is formed to provide a backlash (gap) with the inner peripheral wall 9e of the valve body 9, and the inner peripheral projection 9d is formed to provide a backlash (gap) with the outer peripheral wall 7b of the movable body 7.
[0008]
The operation of the shut-off valve configured as described above will be described below.
[0009]
First, the excitation coil 4 is sequentially energized in a direction to close the valve by a drive circuit connected to the excitation coil 4 of the stator 3 to apply electromagnetic force to the magnetic poles of the rotor 1 to rotate the rotor 1, and screwed to the rotor rotation shaft 5. A force is applied to the moving body 7. Since the moving body 7 is prevented from rotating by the rotation preventing body 8, it moves toward the valve seat 21 along with the rotation of the rotor rotating shaft 5. At this time, the valve body 9 connected to the moving body 7 moves together with the moving body 7 toward the valve seat 21, and during this movement, the urging force of the urging body 10 does not become a load with respect to the rotational force of the rotor 1. . However, when the valve body 9 comes into contact with the valve seat 21, the urging force of the urging body 10 acts as a load on the rotor 1, and the rotational force of the rotor 1 causes the moving body to compress the urging body 10 by a small amount. 7 is moved toward the valve seat 21. When the urging body 10 is slightly compressed to stop the rotation of the rotor 1, the urging force of the urging body 10 is applied so as to press the valve body 9 against the valve seat 21, and a stable valve closing force is applied. The valve is closed.
[0010]
Next, when the valve body 9 is moved away from the valve seat 21 in the opening direction, the drive circuit is switched and driven so that the rotation direction of the rotor 1 is the reverse direction. In the process in which the urging force of the urging body 10 is applied to the valve seat 21 in the valve opening operation, the urging force acts as a force for rotating the rotor 1 in the valve opening direction, so that the load for rotating the rotor 1 is reduced. . In particular, when the pressure difference of the fluid occurs between the upstream and downstream of the valve seat 21 when the valve is closed and the pressure on the valve body 9 in the drawing is high, the force (back) that presses the valve body 9 against the valve seat 21 However, since the urging force of the urging body 10 acts in the direction of reducing the back pressure, the load at the time of opening the valve is reduced. When the valve body 9 moves away from the valve seat 21, the urging force of the urging body 10 becomes independent of the load of the rotor 1, and the rotation of the rotor 1 is rotated by the drive circuit by moving the valve body 9 to the valve opening position by the rotation of the rotor 1. To stop.
[0011]
Thus, the technique which can implement | achieve the stable valve closing force and load reduction at the time of valve opening by arrange | positioning the biasing body 10 is disclosed.
[0012]
[Problems to be solved by the invention]
This type of shut-off valve is generally attached to a gas meter installed outdoors, and is subject to severe temperature changes from temperatures exceeding 50 ° C under direct sunlight in summer to temperatures below -20 ° C in severe winter season. Will be exposed. Under such circumstances, the structural strength that does not break down during the period of use of the gas meter (generally 10 years), and when the microcomputer meter microcomputer determines that the gas usage status is abnormal use, earthquake sensors, gas pressure sensors, gas When the status of sensors such as an alarm device and a carbon monoxide sensor is monitored and judged as a dangerous state, high reliability is required to reliably shut off the gas.
[0013]
the above of In the shut-off valve having such a structure, the member that integrally forms the valve rubber pressing / holding portion 9b, the inner peripheral projection 9d, and the inner peripheral wall 9e of the movable body 7 and the valve body 9 is usually made of synthetic resin as a material because of the complexity of the shape. Selected. Synthetic resins have the property of undergoing creep deformation so as to relieve stress when subjected to stress for a long period of time. On the other hand, when this type of shut-off valve is used as a shut-off valve for the microcomputer meter, the reaction force of the urging body 10 is always applied to the locking portion 15 because the valve is normally open, and the outer periphery of the moving body 7 The state in which the stress is applied to the protrusion 7a and the inner peripheral protrusion 9d of the valve body 9 continues for almost the entire use period of the gas meter. Therefore, in this type of shut-off valve in which the urging body 10 is arranged between the moving body 7 and the valve body 9, the creep deformation of the outer week protrusion 7a and the inner peripheral protrusion 9d due to the reaction force of the urging body 10 is small. However, it is necessary to ensure the reliability that the locking portion 15 has a sufficient structural strength during the period of use and can shut off the gas without disturbing the operation of the urging body 10.
[0014]
However, in the above-described conventional shut-off valve, there is no means for preventing creep deformation in which the inner peripheral wall 9e spreads outward, and the engagement portion 15 is released by continuing to receive the reaction force of the biasing body 10 for a long period of time. May not be able to contact the valve seat 21 and may not be able to shut off the gas. Further, in the case of the configuration like this shut-off valve, in order to make it possible to assemble, it is common to form a longitudinal groove leading to the inner peripheral protrusion 9d and the inner peripheral wall 9e of the valve body 9, and in this case, the inner peripheral wall As shown in FIG. 5, when the valve body 9 receives an eccentric load P due to gas dynamic pressure or the like and is tilted at an angle θ as shown in FIG. There was a problem that the part 15 was easily detached.
[0015]
In the above-described conventional shutoff valve, the valve rubber plate 9a has a hole in the center, and the valve rubber holding portion 9b is press-fitted into the hole to hold the valve rubber plate 9a and the valve rubber holding portion 9b in an airtight manner. Further, the structure is held by press-fitting the valve rubber retainer 9c into the tip protrusion of the valve rubber holding portion 9b. The valve rubber retainer 9c and the pressure-insertion portion of the tip protrusion of the valve rubber holding portion 9b are also creeped during the period of use. There is a problem that the valve rubber retainer 9c may be deformed and fall off, and the airtight structure between the valve rubber plate 9a and the valve rubber holding portion 9b may not be maintained. In addition, the valve rubber holding portion 9b includes an organic substance atmosphere such as a fuel gas that is a low-molecular hydrocarbon, an active gas that is a refined impurity such as moisture, hydrogen sulfide, and sulfur dioxide contained in the gas, and a valve rubber. When exposed to severe temperature changes while in contact with a highly permeable organic compound such as a plasticizer contained in the synthetic rubber constituting the plate 9a, micro cracks and even larger stress cracks occur in the material resin, and the valve rubber plate 9a There has been a problem that the airtightness with the valve rubber holding portion 9b may be broken or leakage may occur from the valve rubber holding portion 9b itself.
[0016]
The shut-off valve device that drives the shut-off valve also compresses the urging body 10 only slightly when the valve body 9 comes into contact with the valve seat 21 and stops the rotation of the rotor 1. The valve closing stroke variation due to the valve cannot be absorbed, and the valve closing stroke becomes insufficient due to skipping of the valve closing signal due to overload during valve closing operation or loosening due to external impact after valve closing, etc., and the gas shutoff reliability decreases. There was a problem that there was a possibility.
[0017]
In view of such a conventional problem, the present invention has a sufficient structural strength that prevents the engagement between the valve body and the moving body due to an eccentric load or temperature stress during long-term use, and has a sufficient structural strength. An object of the present invention is to provide a shutoff valve having high airtight reliability capable of shutting off gas even when a crack is generated in a rubber holding member.
[0018]
In addition, a shut-off valve device with high gas shut-off reliability that is unlikely to be short of the shut-off stroke even if a valve closing signal is skipped due to an overload during valve closing operation or slacking due to an external impact after the valve is closed. The purpose is to provide.
[0019]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention provides an electric rotating mechanism capable of holding a rotational position without being energized, a feeding means disposed on a rotating shaft of the electric rotating mechanism, and a center hole screwed into the feeding means. A movable body that is engageable and has a generally disc-shaped spring support formed on the electric rotation drive mechanism side, an engagement ring portion having a large diameter formed at the other end, and a cylindrical portion having a thin outer diameter formed therebetween. A generally disc-shaped valve seat that can contact a valve seat formed in the flow path, and an inner diameter that is generally formed in a disc shape and holds the valve seat at one end and protrudes toward the electric rotating mechanism at the other end Has a cylindrical portion that is substantially equal to the outer diameter of the engaging ring portion of the moving body and is vertically divided in the axial direction, and the inner diameter is narrower than the outer diameter of the engaging ring portion of the moving body at the end of the cylindrical portion. An engaging claw projecting inward substantially equal to the outer diameter of the cylindrical portion of the moving body is formed, A valve seat holding member engaged and held with a moving body, and a coil spring compressed and held between the moving body and the valve seat holding member and having an inner diameter substantially equal to the outer diameter of the cylindrical portion of the valve seat holding member And constitutes a shutoff valve.
[0020]
As described above, the coil spring is disposed outside the engaging portion between the movable body and the valve seat holding member so that the inner diameter is substantially equal to the outer diameter of the cylindrical portion of the valve seat holding member. It is restricted from spreading outward due to a load or the like, and the engagement portion between the valve seat holding member and the moving body is difficult to be disengaged due to an eccentric load or a temperature stress in a long-term use, and has a sufficient structural strength.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
The shut-off valve of the present invention can be screwed or engaged with the electric rotating mechanism capable of holding the rotational position without being energized, the feeding means disposed on the rotating shaft of the electric rotating mechanism, and the feeding means. A central hole, and a disc-like shape from the end where the feeding means is inserted. Spring holder When Thin outer cylinder And the engagement ring part with a larger outer diameter than this cylindrical part in order The movable body formed, the valve seat that can be in contact with the valve seat formed in the flow path, the valve seat held at one end, and the inner diameter projecting toward the electric rotating mechanism at the other end are related to the movable body. The movable body has a cylindrical portion that is substantially the same as the outer diameter of the mating ring portion, and has an inner diameter that is narrower than the outer diameter of the engaging ring portion of the movable body at the end of the cylindrical portion. An engagement claw protruding inward that is substantially equal to the outer diameter of the part is formed and held in engagement with the moving body Be done A valve seat holding member and a coil spring that is compressed and held between the movable body and the valve seat holding member, and has an inner diameter that is substantially equal to the outer diameter of the cylindrical portion of the valve seat holding member. is there.
[0022]
Since the coil spring is disposed outside the engaging portion between the movable body and the valve seat holding member, the inner diameter is substantially equal to the outer diameter of the cylindrical portion of the valve seat holding member, the cylindrical portion is subjected to creep deformation or eccentric load. It is possible to provide an excellent shut-off valve having sufficient structural strength by restricting spreading outward and preventing the engagement portion between the valve seat holding member and the moving body from coming off due to an eccentric load or temperature stress during long-term use. .
[0023]
In addition to the above-described structure, the shut-off valve of the present invention is a bag in which the valve seat has a generally disc shape without a fitting hole, and projects to the outer periphery on the valve seat holding member side and has an inner diameter smaller than the outer diameter of the valve seat holding member. It is the product made from the flexible body in which the shape folding part was formed.
[0024]
Then, a bag-like folded portion is formed on the outer periphery of the valve seat, and the valve seat retainer is held inside the folded portion, so that no valve rubber presser is required, and the airtightness due to the fall off of the valve rubber presser There is no destruction. In addition, since there is no through hole in the valve seat, even if cracks occur in the valve seat holding member due to temperature stress in an organic atmosphere during long-term use, it does not lead to leakage and has an excellent shut-off valve with high hermetic reliability. Can be provided.
[0025]
The shut-off device of the present invention is the above-mentioned Blocking the configuration The shut-off valve is constituted by a driving means for outputting more signals even after the valve seat of the shut-off valve comes into contact with the valve seat and the coil spring is compressed to the bottom dead center during the closing operation.
[0026]
Since the valve seat of the shut-off valve abuts against the valve seat and the coil spring is compressed to the bottom dead center during the valve closing operation, a slightly more signal is output. It is possible to provide a stable shut-off valve device that is unlikely to cause a shortage of valve closing stroke even when signal reading is skipped or slackening due to external impact after valve closing occurs.
[0027]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
[0028]
Example 1
1, 2, and 3 are cross-sectional views of the shut-off valve according to the first embodiment of the present invention in the open state, during the shut-off operation, and the closed state, respectively, and FIG. It is a perspective view which shows the shape of a stator and a support frame.
[0029]
1 and 4, an exciting coil 43 in which a conducting wire 42 is wound around a substantially bobbin-shaped coil bobbin 41, and a first electromagnetic yoke 44 having a cylindrical portion on the outer periphery and a comb-shaped magnetic pole on the inner periphery. And two sets of a second electromagnetic yoke 45 having a generally disc shape and a comb-like magnetic pole on the inner periphery, which are arranged so as to sandwich the exciting coil 43 between the electromagnetic yoke 44 and each other. The second electromagnetic yoke 45 is placed in contact with the disk portion to form a stator 46. The coil bobbin 41 is preferably made of synthetic resin and has heat resistance such as polybutylene terephthalate (PBT) and good electrical insulation. The first electromagnetic yoke 44 and the second electromagnetic yoke 45 are made of a steel plate such as a low-carbon steel plate, an electromagnetic soft iron plate, or a silicon steel plate, and are subjected to rust prevention treatment such as galvanization, aluminum plating, and chromic acid treatment film on the surface. Economically, a pre-plated steel plate such as a galvanized steel plate is desirable. The comb-shaped magnetic poles of the first electromagnetic yoke 44 and the second electromagnetic yoke 45 mesh with a predetermined gap, and the two sets of comb teeth are substantially the same as the other sets of comb teeth in the rotation direction. It arrange | positions so that it may be located in a clearance gap part.
[0030]
Coaxially inside the stator 46, there are two stages of bottom holes 47a and 47b, large and small cylindrical portions 47c and 47d, and a large diameter cylindrical portion 47c with a flange 47e at the open end of the large diameter cylindrical portion 47c. There is no metallic partition 47. The material of the partition wall 47 can be selected from rigid bodies such as non-magnetic stainless steel plates, copper alloys, aluminum alloys, synthetic resins, and ceramics, but for reasons such as corrosion resistance, strength, creep resistance, and thin wall workability, austenite A stainless steel plate drawn by drawing is optimal, and a solution obtained by applying a solution heat treatment after drawing to remove residual internal stress and crystal grain refinement is desirable.
[0031]
A first bearing 48 made of synthetic resin having a center hole 48a is fitted into the inside of the side surface of the small-diameter cylindrical portion 47d of the partition wall 47. The cylindrical portion 47d of the partition wall 47 and the first bearing 48 are fitted with an interference fit. Between the fitting portion 48b of the first bearing 48 and the center hole 48a, a thin rippled stress relaxation portion 48c is formed. Further, a stopper 48d is formed so as to contact the bottom 47a of the partition wall 47. The material of the first bearing 48 is selected from synthetic resins having self-lubricating properties such as various synthetic resins in which polyacetal (POM), polyamide (PA) and polytetrafluoroethylene (PTFE) powder and graphite particles are blended. Although possible, polyacetal is the best because of its low coefficient of friction and economic reasons. Since this polyacetal has a relatively large stress creep and is soft, when setting an interference fit, it is necessary to set a relatively large allowance. For example, the inner diameter of the cylindrical portion 47d of the partition wall 47 is 8 mm. In this case, the outer diameter of the fitting portion 48b of the first bearing 48 is appropriately about 8.05 to 8.1 mm.
[0032]
On the open end side of the pan side surface of the large-diameter cylindrical portion 47c of the partition wall 47, a second bearing 49a, a cylindrical portion 49b having an open end 49g perpendicular to the central axis on the side surface, and a collar portion 49c on the outer periphery are provided. A synthetic resin lid 49 having the same axis is fitted into the flange 47 e of the partition wall 47 in contact with the flange 47 e. The cylindrical portion 47c of the partition wall 47 and the fitting insertion portion 49e of the lid 49 are fitted with an interference fit. Between the fitting portion 49e of the lid 49 and the second bearing 49a, a thin rippled stress relaxation portion 49d is formed. As the material of the lid 49, polyacetal is optimal as in the first bearing 48. The interference fit between the cylindrical portion 47c of the partition wall 47 and the fitting insertion portion 49e of the lid 49 may be relatively loose because there is another fixing means described later, and to prevent the disk portion 49f from wavy. For example, when the inner diameter of the cylindrical portion 47c of the partition wall 47 is 18 mm, the outer diameter of the fitting insertion portion 49e of the lid 49 is appropriately about 18.02 to 18.08. On the inner surface of the cylindrical portion 49b of the lid 49, convex ribs 50 parallel to the central axis are formed at two locations 180 ° apart on the circumference.
[0033]
Inside the partition wall 47, a cylindrical permanent magnet 51 polarized in the circumferential direction, a rotating shaft 53 having a feed screw 52 formed at one end, the permanent magnet 51, and the rotating shaft 53 are held coaxially. A rotor 55 composed of a sleeve 54 that rotates is loosened so that the end of the rotary shaft 53 on the side of the feed screw 52 can be rotated to the second bearing 49a of the lid 49 and the opposite end can be rotated to the center hole 48a of the first bearing 48. It is inserted and arranged.
[0034]
A mounting plate 57 that can be attached to the fluid chamber 56 is formed with a cylindrical stepped portion 57b having an inner diameter slightly larger than the outer diameter of the central hole 57a and the large-diameter cylindrical portion 47c of the partition wall 47 at the center. A claw-like fitting portion 57c is formed at the place. The end of the large-diameter cylindrical portion 47c of the partition wall 47 is inserted into the stepped portion 57b, and the cylindrical portion 49b of the lid 49 passes through the center hole 57a and protrudes toward the fluid chamber 56, and the outer periphery of the cylindrical portion 47c and the stepped portion Between the inner periphery of 57 b, an elastic seal member 58 such as a synthetic rubber O-ring is compressed in the circumferential direction with respect to the central axis of the partition wall 47. The flange portion 49 c of the lid 49 is held between the bottom surface 57 d of the stepped portion 57 b of the attachment plate 57 and the flange 47 e of the partition wall 47.
[0035]
A seal member 69 is compressed and held between the seal surface 57e of the mounting plate 57 and the fluid chamber 56, and the space between the mounting plate 57 and the fluid chamber 56 is kept airtight.
[0036]
A stator 46 is disposed in contact with the partition plate 47 side surface of the mounting plate 57. The stator 46 and the partition wall 47 are pressed against each other and sandwiched between the mounting plate 57 and both ends thereof are fitted portions 57c of the mounting plate 57. A generally U-shaped support frame 59 is disposed. The support frame 59 is formed with an engaging portion 59 b that can be engaged with the stator 46 to prevent the stator 46 from rotating. In this example, the engaging portion 59b has a convex shape when viewed from the back, and the front end portion is inserted into and engaged with a hole opened in the electromagnetic yoke 44, and the electromagnetic yoke 44 is attached to the mounting plate 57 by the convex stepped portion. It is energizing to the side. Between the stator 46 and the seal member 58, a backup ring 60 for preventing the seal member 58 from dropping from the stepped portion 57b of the mounting plate 57 is disposed. The material of the mounting plate 57 and the support frame 59 is a rigid material having gas resistance, corrosion resistance and strength, such as surface-treated steel plate, stainless steel plate, copper alloy plate and aluminum alloy plate. A treated steel plate is easy to select.
[0037]
The moving body 61 disposed in the fluid chamber 56 has a center hole 61a screwed into the feed screw 52 of the rotating shaft 53, a substantially disk-shaped spring receiver 61b formed on the stator 46 side, and a large diameter at the other end. An engagement ring portion 61c is formed, and a cylindrical portion 61d having a small diameter is formed between them. On the outer periphery of the spring receiver 61b, concave portions 61e that can engage with the ribs 50 of the lid 49 are formed at four locations at intervals of 90 ° on the circumference. When the concave portion 61 e is engaged with the rib 50, the rotation of the moving body 61 and the bearing 49 is prevented, and the rotation operation of the feed screw 52 is converted into the front-rear operation of the moving body 61. The material of the moving body 61 can be selected from synthetic resins having self-lubricating properties such as polyacetal (POM), polyamide (PA), polytetrafluoroethylene (PTFE) powder, and various synthetic resins blended with graphite particles. However, polyacetal is optimal because of its low friction coefficient and economic reasons.
[0038]
The valve body 62 is in contact with the valve seat 65 formed in the fluid chamber 56 and is substantially disc-shaped and is made of a flexible valve seat 63 such as synthetic rubber, and the surface of the valve seat 63 on the stator 46 side. The valve seat holding member 64 is made of a rigid body such as a synthetic resin disposed in contact therewith. The valve seat 63 has a disc shape with no through-holes, and projects to the valve seat holding member 64 side on the outer periphery to form a bag-like folded portion 63 a having an inner diameter smaller than the outer diameter of the valve seat holding member 64. It is loosely fitted to embrace. The valve seat holding member 64 has a cylindrical portion 64b that protrudes toward the stator 46 and has an inner diameter that is substantially equal to the outer diameter of the engagement ring portion 61c of the moving body 61 and is formed with a longitudinal division 64a in the axial direction. At the end of 64 b, there is an engaging claw 64 c projecting inward that has an inner diameter smaller than the outer diameter of the engaging ring portion 61 c of the moving body 61 and substantially equal to the outer diameter of the cylindrical portion 61 d of the moving body 61. It is arranged together. A gap 69 is provided between the tip of the cylindrical portion 64 b of the valve seat holding member 64 and the spring receiver 61 b of the moving body 61. The material of the valve seat holding member 64 is preferably a synthetic resin material having gas resistance such as polyacetal (POM), polyamide (PA), polybutylene terephthalate (PBT).
[0039]
A coil spring 66 having an inner diameter substantially equal to the outer diameter of the cylindrical portion 64 b of the valve seat holding member 64 is compressed and held between the moving body 61 and the valve seat holding member 64.
[0040]
The moving body 61 and the valve body 62 constitute a valve mechanism, and the open end 49g of the lid 49 abuts the back surface 64d of the valve seat holding member 64 at the moving bottom dead center on the valve opening side, In addition, the axial length is set so that there is a gap between the lid 49 and the moving body 61.
[0041]
Between the sleeve 54 of the rotor 55 and the first bearing 48 and the lid 49, a thrust washer made of a synthetic resin having self-lubricating properties such as polytetrafluoroethylene (PTFE) or polyamide (PA) blended with graphite particles. 67 and 68 are arranged.
[0042]
Next, the operation and action of the shutoff valve of the first embodiment will be described.
[0043]
When the gas usage state is not abnormal and the signals from various sensors do not indicate danger, there is no power supply from the control unit (not shown) of the microcomputer meter, and the shut-off valve is a moving body as shown in FIG. 61 is on the side of the stator 46, and the valve body 62 is kept open from the valve seat 65 so that gas can flow therethrough.
[0044]
When the use state of the gas is abnormal or the signals from various sensors indicate danger, the microcomputer meter control unit drives the phase difference between the conductors 42 of the exciting coil 43 via a driving means (not shown). Is applied to rotate the rotor 55 forward. Since the moving body 61 is prevented from rotating by the concave portion 61e engaging with the rib 50, the rotation operation of the feed screw 52 interlocked with the rotor 55 is converted into the front-rear operation of the moving body 61 and is engaged with the moving body 61. The valve body 62 is moved to a position where the valve seat 63 abuts on the valve seat 65, and is in the state shown in FIG. When the moving body 61 further advances toward the valve seat 65, the coil spring 66 is further compressed, the tip of the cylindrical portion 64b of the valve seat holding member 64 and the spring receiver 61b of the moving body 61 come into contact, and the valve seat 63 bends. The repulsive force of the moving body 61 finally becomes larger than the thrust of the feed screw 52, and the rotation of the rotor 55 stops. Even after the control means is compressed to the bottom dead center of the coil spring 66, it outputs a slightly more signal. Thus, the valve body 62 is urged against the valve seat 65 by the coil spring 66 and the gas is shut off. The shut-off valve in the closed state is shown in FIG.
[0045]
Thereafter, even if the control unit of the microcomputer meter stops energization, the rotor 55 maintains the state due to the holding torque, and therefore the valve body 62 maintains the closed state in which the valve seat 65 is urged by the coil spring 66. To do.
[0046]
When the controller of the microcomputer meter determines that the danger is released from the signals from the various sensors and can be restored, or when the gas user recovers the dangerous condition and operates the return switch provided on the meter or remote control panel, When a gas supplier or the like sends a remote return command by communication, the control unit of the microcomputer meter applies a pulsed current having an opposite phase difference to each conducting wire 42 of the exciting coil 43 and rotates the rotor 55 in the reverse direction. Let Then, it is sent to the feed screw 52 and the moving body 61 moves to the stator 46 side, the valve body 62 is detached from the valve seat 65, and the gas can flow. The moving body 61 further moves to the stator 46 side, and finally, the back surface 64d of the valve seat holding member 64 of the valve body 62 comes into contact with the open end 49g of the cylindrical portion 49b of the lid 49 and becomes a moving bottom dead center. Stops. Thereafter, even if the control unit of the microcomputer meter stops energization, the rotor 55 maintains the state due to the holding torque, and maintains the valve open state shown in FIG.
[0047]
Now, this kind of shut-off valve is generally attached to a gas meter installed outdoors, and it is a severe temperature from a temperature exceeding 50 ° C. under direct sunlight in summer to a temperature lower than −20 ° C. in the severe winter season. You will be exposed to change. Under such circumstances, the structural strength that does not break down during the period of use of the gas meter (generally 10 years), and when the microcomputer meter microcomputer determines that the gas usage status is abnormal use, earthquake sensors, gas pressure sensors, gas When the state of sensors such as an alarm device and a carbon monoxide sensor is monitored and judged as a dangerous state, high reliability is required to reliably shut off the gas.
[0048]
The shutoff valve of the present embodiment has an inner diameter substantially equal to the outer diameter of the cylindrical portion 64b of the valve seat holding member 64 outside the engaging portion between the moving body 61 and the valve seat holding member 64, that is, outside the engaging claw 64c. Since the coil spring 66 is provided, the cylindrical portion 64b is prevented from spreading outward due to creep deformation or eccentric load, and the engagement portion between the valve seat holding member 64 and the moving body 61 due to eccentric load or temperature stress during long-term use. Therefore, it is possible to provide an excellent shut-off valve having a sufficient structural strength.
[0049]
Further, a bag-like folded portion 63a is formed on the outer peripheral portion of the valve seat 63, and the valve seat holding member 64 is held so as to be incorporated inside the folded portion 63a. There is no destruction of airtightness due to dropout. Further, since there is no through hole in the valve seat 63, even if a crack occurs in the valve seat holding member 64 due to temperature stress in an organic atmosphere during long-term use, the valve seat 63 does not leak and has excellent airtight reliability. A valve can be provided.
[0050]
Further, the drive device (not shown) for driving the shut-off valve outputs a slightly more signal even after the valve seat 63 abuts against the valve seat 65 and the coil spring 66 is compressed to the bottom dead center during the valve closing operation. To provide a stable shut-off valve device that does not cause a shortage of valve closing stroke even when a valve closing signal is skipped due to an overload during valve closing operation, or when loosening due to an external impact after valve closing occurs. Can do.
[0051]
In FIG. 1, the rib 50 is provided on the lid 49 and the concave portion 61e is provided on the moving body 61. However, the second bearing has a groove, and the movable body is provided with a convex portion to engage and prevent rotation. It may be a means. In addition, the set of the exciting coil 43, the first electromagnetic yoke 44, and the second electromagnetic yoke 45 is two sets, but may be three sets or more. Further, although the seal member 58 is arranged to be compressed in the radial direction, it may be compressed in the axial direction. However, in this case, there is a high possibility that the compression rate of the seal member 58 is reduced by the creep deformation of the collar 49c of the lid 49. Therefore, a portion that affects the axial compression rate of the seal member 58 such as the collar 49c is used. It is necessary to form so as not to interpose a synthetic resin. The thrust bearings 67 and 68, which are sliding bearings, are used as the thrust bearings, but may be rolling bearings such as ball bearings. However, in the case of a shut-off valve of a microcomputer meter, the use of lubricating oil is not preferable because it is often left in a stationary state for a long period of time. Further, although the feed means is a feed screw, it may be a cylindrical cam or the like. Further, although the feeding means and the moving body are male screws and female screws, a combination of a worm and a rack may be used.
[0052]
The valve seat 63 includes the valve seat holding member 64. However, the valve seat 63 may be fitted at the center, and the valve seat holding member 64 is formed with a central axis so that the valve seat is air-tightly penetrated by another fixing member. You may fasten. However, in this case, the valve seat holding member is cracked due to the effect that there is no destruction of the airtightness due to the fall off of the valve rubber presser or the temperature stress in the organic substance atmosphere during long-term use. Even if it occurs, an effect that does not lead to leakage cannot be realized.
[0053]
【The invention's effect】
As apparent from the above description, the shutoff valve of the present invention has the following effects.
[0054]
Since a coil spring having an inner diameter substantially equal to the outer diameter of the cylindrical portion of the valve seat holding member is disposed outside the engaging portion between the movable body and the valve seat holding member, the cylindrical portion expands outward due to creep deformation or eccentric load. Therefore, it is possible to provide an excellent shut-off valve having sufficient structural strength because the engagement portion between the valve seat holding member and the moving body is unlikely to be disengaged due to eccentric load, temperature stress in long-term use, and the like.
[0055]
In addition, a bag-like folded part is formed on the outer periphery of the valve seat, and the valve seat retainer is held inside the folded part, so that no valve rubber presser is required. There is no destruction. In addition, since there is no through hole in the valve seat, even if cracks occur in the valve seat holding member due to temperature stress in an organic atmosphere during long-term use, it does not lead to leakage and has an excellent shut-off valve with high hermetic reliability. Can be provided.
[0056]
Furthermore, since the valve seat of the shut-off valve abuts against the valve seat and the coil spring is compressed to the bottom dead center during the valve closing operation, a slightly more signal is output, so that the valve is closed due to an overload during the valve closing operation. It is possible to provide a stable shut-off valve device that is unlikely to cause a shortage of valve closing stroke even when a valve signal is skipped or slackening due to an external impact after the valve is closed.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a shutoff valve in an opened state according to a first embodiment of the present invention.
FIG. 2 is a cross-sectional view of the shut-off valve during shut-off operation
FIG. 3 is a sectional view of the shut-off valve in a closed state
FIG. 4 is a sectional view of a conventional shut-off valve in an open state.
FIG. 5 is a cross-sectional view of the vicinity of the valve body of the shut-off valve
[Explanation of symbols]
46 Stator (electric rotating mechanism)
55 Rotor (electric rotating mechanism)
53 Rotating shaft
52 Feed screw (feed means)
61 Mobile
61b Spring receiver
61c engagement ring part
61d Cylindrical part
63 Valve seat
63a Folding part
64 Valve seat holding member
64a Vertical split
64b cylindrical part
64c engaging claw
65 Valve seat
66 Coil spring

Claims

An electric rotating mechanism capable of holding a rotational position without being energized; a feeding means disposed on a rotating shaft of the electric rotating mechanism; and a center hole that can be screwed or engaged with the feeding means, and the feeding means those but a moving body in order to form a thick engaging ring portion having an outer diameter than the cylindrical portion and the disk-shaped spring receiver and the outer diameter of thin cylinder portion from the end to be inserted, the valve seat formed in the flow path A valve seat that can be contacted, the valve seat is held at one end, and the inner diameter that protrudes toward the electric rotating mechanism at the other end is substantially equal to the outer diameter of the engagement ring portion of the movable body, and is divided vertically in the axial direction. And an engaging claw projecting inwardly is formed at the end of the cylindrical portion, whose inner diameter is narrower than the outer diameter of the engaging ring portion of the moving body and is substantially equal to the outer diameter of the cylindrical portion of the moving body. and, a valve seat retaining member is held in engagement with said moving member, said valve seat holding with the mobile Is held compressed between the member, the shut-off valve whose inner diameter was composed of approximately equal coil spring and the outer diameter of the cylindrical portion of the valve seat retaining member.

The valve seat is generally a disk-shaped, cut-off of claim 1 wherein said valve flexible member forming a folded portion pouched smaller inner diameter than the outer diameter of the valve seat retaining member protrudes sheet holding member side to the outer periphery valve.

It said valve seat is shut-off valve abuts the coil spring according to claim 1 or 2, wherein composed of a driving means for outputting a further valve close signal after being compressed to the bottom dead center the valve seat when the valve is closed operation.