JP3908817B2

JP3908817B2 - Emergency shut-off valve

Info

Publication number: JP3908817B2
Application number: JP05695797A
Authority: JP
Inventors: 定夫関根
Original assignee: Toyooki Kogyo Co Ltd
Current assignee: Toyooki Kogyo Co Ltd
Priority date: 1997-02-24
Filing date: 1997-02-24
Publication date: 2007-04-25
Anticipated expiration: 2017-02-24
Also published as: JPH10231943A

Description

【０００１】
【発明の属する技術分野】
本発明は、通過流量の急増により流路を遮断する緊急遮断弁に関する。
【０００２】
【従来の技術】
従来、この種の緊急遮断弁として実開昭６１−４１９７１号公報に示されるものがある。このものは、貫通孔の他端開口側としてのＯＵＴポート側において、ホース、配管等の破損等があった場合、ＯＵＴポート側の圧力が急激に低下し、球弁保持部材に穿設した４個の絞り孔としての薄刃オリフィス前後において大きな圧力差が生じて遮断弁内を流れる通過流量が急増するが、この急増した通過流量が瞬時に閉弁流量に達し、球弁は薄刃オリフィス前後の圧力差に基づく作用力で圧縮コイルばねのばね力に抗して押圧されて瞬時に弁座に着座し、貫通孔の一端開口側としてのＩＮポート側からＯＵＴポート側への流れを遮断している。そして、球弁によりＩＮポート側からＯＵＴポート側への流れを遮断する閉弁流量は、球弁保持部材に穿設する薄刃オリフィスの個数により設定し、薄刃オリフィスの個数が異なる複数種の球弁保持部材の一つを適宜選択して弁本体に組み付け、用途に応じた最適な仕様としている。また、ＯＵＴポート側に流出する流体が圧縮コイルばねの微細な線間すきまを通ることなく外周側を通って流れるよう圧縮コイルばねの外周側に４個の迂回流路を周方向へ等間隔に設けている。
【０００３】
【発明が解決しようとする課題】
ところが、かかる従来の緊急遮断弁では、薄刃オリフィスは弁本体の奥側に位置して球弁保持部材に径方向へ穿設しているため、弁本体に球弁保持部材を組み付けた製品完成後の検査時に、外部から薄刃オリフィスの個数を視認し難く、閉弁流量が仕様に合っているか否かの確認が困難であった。
【０００４】
本発明は、製品完成後の検査時に外部から絞り孔の個数を容易に確認でき、閉弁流量が仕様に合っているか否かを即座に判別し得るようにした緊急遮断弁を提供することを課題としている。
【０００５】
【課題を解決するための手段】
このため、本発明の緊急遮断弁は、流体が流通する貫通孔を弁本体の内部に軸方向へ貫通し、貫通孔の両端を弁本体の一側面と他側面とにそれぞれ開口し、貫通孔は弁本体の内部で大径孔部と小径孔部とを連設した段付き形状に設けてその連設段部に弁座を形成し、弁座に着座して貫通孔の大径孔部と小径孔部との間を遮断する球状の弁体を軸方向へ移動自在に保持する球弁保持部材を貫通孔の大径孔部側に備え、球弁保持部材は貫通孔の弁本体一側面に開口する一端開口側へ嵌挿して弁本体に固定する基部と、基部より軸方向の内方へ突設する連結部と、連結部の内方端に連設して弁座と軸方向に対向し弁体を保持する保持部とから構成し、保持部は貫通孔の大径孔部に位置して自身の外周面と大径孔部の内周面との間に流体が流通する環状間隙を形成し、環状間隙は保持部先端を介して弁座に連なると共に、連結部の外周面と貫通孔の内周面との間に形成した第２環状間隙を介して基部に連なり、基部には貫通孔の軸方向と直交して貫通孔を塞ぐ内壁を有し、内壁には軸方向へ貫通して貫通孔の一端開口と環状間隙との間を通じさせる絞り孔を設け、絞り孔より前側である貫通孔の一端開口側の流体の圧力を弁体に弁座への着座方向に作用させる連通孔を連結部に軸方向へ貫通し、絞り孔前側の圧力に抗して絞り孔後側である環状間隙側の流体の圧力を保持部先端を介して弁体に弁座からの離脱方向に作用し、さらに弁体を弁座からの離脱方向に付勢するばねを貫通孔の小径孔部側に収装し、弁本体には貫通孔の両端が開口する一側面と他側面との外周にそれぞれ接続用のねじ部を設けて成る。
【０００６】
この場合、貫通孔の小径孔部側に収装して弁体を弁座からの離脱方向に付勢するばねは、そのコイル平均径を弁体の直径より小さくした小径部とそのコイル平均径を貫通孔の内径に近似した大径部とを連設した圧縮コイルばねで、貫通孔の弁本体他側面に開口する他端開口側の内周面に設けた止め輪で大径部を抜け止めすると共に、小径部先端を弁体に当接しても良い。そして、圧縮コイルばねの大径部と貫通孔の内周面に設けた止め輪との間に、弁体を弁座からの離脱方向に付勢するばね力を調整するためのカラー部材を介在しても良い。
【０００７】
また、弁本体の他側面外周には、ねじ部に近設して他側面に向けて順次縮径するおすシート部を形成し、おすシート部は端部に向けて順次拡径する配管のめすシート部と直接接合しても良い。
【０００８】
また、弁本体の他側面に開口する貫通孔の他端には、他側面に向けて順次拡径するめすシート部を形成し、めすシート部は端部に向けて順次縮径する配管のおすシート部と直接接合しても良い。
【０００９】
かかる本発明の緊急遮断弁によると、貫通孔の他端開口側から一端開口側へ流体が流通する場合には、他端開口側の流体は弁座、球弁保持部材の保持部先端、環状間隙、第２環状間隙、球弁保持部材の基部内壁を貫通した絞り孔を介して一端開口側へ流れる。このとき、絞り孔で圧力降下が生じるため、球弁保持部材の保持部先端を介して弁体に弁座からの離脱方向に作用する環状間隙側の流体の圧力が、球弁保持部材の連結部に貫通の連通孔を介して弁体に弁座への着座方向に作用する一端開口側の流体の圧力より高く、弁体は絞り孔前後の圧力差に基づく作用力とばねのばね力とで弁座から離脱している。また、貫通孔の一端開口側から他端開口側へ流体が流通する場合には、一端開口側の流体は球弁保持部材の基部内壁を貫通した絞り孔、第２環状間隙、環状間隙、球弁保持部材の保持部先端、弁座を介して他端開口側へ流れる。このとき、絞り孔で圧力降下が生じるため、連結部の連通孔を介して弁体に弁座への着座方向に作用する一端開口側の流体の圧力が、保持部先端を介して弁体に弁座からの離脱方向に作用する環状間隙側の流体の圧力より高く、この圧力差に基づく作用力が弁体に弁座への着座方向に作用するが、この弁座への着座方向に作用する作用力よりばねのばね力が大きいので、弁体は弁座から離脱している。この貫通孔の一端開口側から他端開口側及び他端開口側から一端開口側へ流体が流通する双方の場合に、他端開口側に接続した配管等が破損等して異常事態が生じると、環状間隙側の圧力が大きく低下し、絞り孔前後に大きな圧力差が生じて通過流量が急増するが、この急増した通過流量が瞬時に閉弁流量に達し、弁体は絞り孔前後の大きな圧力差に基づく作用力でばねのばね力に抗して瞬時に弁座に着座し、一端開口側から他端開口側への流体の流通を阻止する。そして、絞り孔は球弁保持部材の基部内壁に軸方向へ貫通しており、絞り孔の個数を貫通孔の一端開口を介して外部から容易に視認することができる。このため、緊急遮断弁は、製品完成後の検査時に外部から絞り孔の個数を容易に確認でき、閉弁流量が仕様に合っているか否かを即座に判別することができる。
【００１０】
【発明の実施の形態】
以下、本発明の一実施形態を図面に基づき説明する。
図１及び図２において、１は弁本体で、軸方向の中央には、スパナ等の工具が係合する六角形状の締め付け操作部２を形成し、一側面と他側面との外周にはそれぞれ接続用のねじ部３、４を設け、他側面の外周に設けたねじ部４に近設して他側面に向けて順次縮径するおすシート部５を形成し、おすシート部５は図示しない端部に向けて順次拡径する配管のめすシート部と直接接合するよう設けている。
【００１１】
６は弁本体１の内部に軸方向へ貫通した貫通孔で、両端を弁本体１の一側面と他側面とにそれぞれ開口し、弁本体１の一側面に開口する一端開口側には内周面を拡径して段部６Ａを形成している。貫通孔６は弁本体１の内部で大径孔部６Ｂと小径孔部６Ｃとを連設した段付き形状に設け、大径孔部６Ｂと小径孔部６Ｃとの連設段部には弁座７を形成している。８は弁座７に着座して貫通孔６の大径孔部６Ｂと小径孔部６Ｃとの間を遮断する球状の弁体で、球弁保持部材９に軸方向へ移動自在に保持している。
【００１２】
球弁保持部材９は貫通孔６の大径孔部６Ｂ側に備え、基部９Ａと連結部９Ｂと保持部９Ｃとから構成している。基部９Ａは円筒状に形成してその軸方向一端に外周面から径方向へ突設した環状凸部９Ｄを有すると共に、その軸方向他端に軸方向と直交して内壁９Ｅを有している。そして、基部９Ａは貫通孔６の弁本体１一側面に開口する一端開口側へ嵌挿し、環状凸部９Ｄを貫通孔６の段部６Ａに係合して止め輪１０で一端開口側からの抜け止めをして弁本体１に固定し、貫通孔６への嵌挿で内壁９Ｅが貫通孔６を塞いでいる。
【００１３】
連結部９Ｂは基部９Ａの内壁９Ｅ中心より軸方向の内方へ突設し、自身の外周面と貫通孔６の内周面との間に流体が流通する第２環状間隙１１を形成している。保持部９Ｃは連結部９Ｂの内方端に連設して弁座７と軸方向に対向し、弁座７に向けて開口する窪み９Ｆに弁体８を軸方向へ移動自在に保持し、自身の先端と弁座７との間には軸方向の間隔を有していると共に、自身の外周面と大径孔部６Ｂの内周面との間に流体が流通する環状間隙１２を形成している。
【００１４】
環状間隙１２は保持部９Ｃ先端を介して弁座７に連なると共に、第２環状間隙１１を介して基部９Ａの内壁９Ｅに連なっている。１３Ａ、１３Ｂ、１３Ｃ、１３Ｄ、１３Ｅ、１３Ｆは内壁９Ｅを軸方向へ貫通して貫通孔６の一端開口と環状隙間１２との間を通じさせる絞り孔で、連結部９Ｂの回りに周方向へ等間隔に６個を設けている。１４は連結部９Ｂの内部に軸方向へ貫通した連通孔で、軸方向の一端が基部９Ａの内壁９Ｅに開口すると共に、軸方向の他端が保持部９Ｃの窪み９Ｆ底面に開口し、絞り孔１３Ａ、…、１３Ｆの前側である貫通孔６の一端開口側の流体の圧力を弁体８に弁座７への着座方向に作用して設けている。そして、連通孔１４は基部９Ａの内壁９Ｅに開口する一端に流体を絞る小孔部１４Ａを有している。
【００１５】
弁体８には絞り孔１３Ａ、…、１３Ｆの前側圧力に抗して絞り孔１３Ａ、…、１３Ｆの後側である環状間隙１２側の流体の圧力を保持部９Ｃ先端を介して弁座７からの離脱方向に作用して設けている。１５は弁体８を弁座７からの離脱方向に付勢するばねで、貫通孔６の小径孔部６Ｃ側に収装している。ばね１５はそのコイル平均径を弁体８の直径より小さくした小径部１５Ａとそのコイル平均径を貫通孔６の内径に近似した大径部１５Ｂとを連設した圧縮コイルばねとし、貫通孔６の弁本体１他側面に開口する他端開口側の内周面に設けた止め輪１６に円筒状のカラー部材１７を介在して大径部１５Ｂを当接して抜け止めすると共に、小径部１５Ａ先端を弁体８に当接している。そして、貫通孔６を流通する流体は、ばね１５の小径部１５Ａと大径部１５Ｂとの連設部の径方向へ十分に大きな線間すきまを通って小径部１５Ａ外周側と大径部１５Ｂ内周側との間を流通する。カラー部材１７は軸方向の長さ寸法が異なる他のカラー部材に変更することでばね１５のばね力を調整する。
【００１６】
図３は本発明の緊急遮断弁の使用例を示すもので、電磁方向切換弁１８により、負荷流路Ａを介しシリンダ１９のヘッド側室１９Ａへ流体を供給してロッド側室１９Ｂの流体を負荷流路Ｂを介し排出するとき上昇作動し、負荷流路Ｂを介しロッド側室１９Ｂへ流体を供給してヘッド側室１９Ａの流体を負荷流路Ａを介し排出するとき下降作動する。シリンダ１９のヘッド側室１９Ａは常時下方向に負荷され、ヘッド側室１９Ａへの負荷流路Ａには、ねじ部３をシリンダ１９のポートに螺着して直接接続すると共におすシート部５に配管のめすシート部を直接接合してねじ部４に配管を接続するか、若しくはねじ部３、４により配管途中に介在させるよう接続するかして、貫通孔６の一端開口をシリンダ１９のヘッド側室１９Ａに、貫通孔６の他端開口を電磁方向切換弁１８にそれぞれ通じさせる向きで緊急遮断弁Ｃを設置している。なお、Ａ１、Ｂ１は負荷流路Ａ、Ｂでのホース部分である。
【００１７】
次に、かかる構成の作動を、図１及び図２に示す緊急遮断弁を使用した図３の使用例に基づいて説明する。
負荷流路Ａに異常がない正常状態で、シリンダ１９を上昇作動する場合には、緊急遮断弁Ｃは貫通孔６の他端開口側からばね１５の大径部１５Ｂ内周側、ばね１５の連設部の線間すきま、ばね１５の小径部１５Ａ外周側、弁座７、球弁保持部材９の保持部９Ｃ先端、環状間隙１２、第２環状間隙１１、球弁保持部材９の基部９Ａの内壁９Ｅを貫通した絞り孔１３Ａ、…、１３Ｆを介して貫通孔６の一端開口側へと流体が流通する。このとき、絞り孔１３Ａ、…、１３Ｆで圧力降下が生じるため、保持部９Ｃ先端を介して弁体８に弁座７からの離脱方向に作用する環状間隙１２側の流体の圧力が、連通孔１４を介して弁体８に弁座７への着座方向に作用する一端開口側の流体の圧力より高く、弁体８はこの圧力差に基づく作用力とばね１５のばね力とで弁座７から離脱して球弁保持部材９の保持部９Ｃの窪み９Ｆ内に保持されている。
【００１８】
また、この正常状態でシリンダ１９を下降作動する場合には、緊急遮断弁Ｃは貫通孔６の一端開口側から球弁保持部材９の基部９Ａの内壁９Ｅを貫通した絞り孔１３Ａ、…、１３Ｆ、第２環状間隙１１、環状間隙１２、球弁保持部材９の保持部９Ｃ先端、弁座７、ばね１５の小径部１５Ａ外周側、ばね１５の連設部の線間すきま、ばね１５の大径部１５Ｂ内側を介して貫通孔６の他端開口側へと流体が流通する。このとき、絞り孔１３Ａ、…、１３Ｆで圧力降下が生じるため、連通孔１４を介して弁体８に弁座７への着座方向に作用する一端開口側の流体の圧力が、保持部９Ｃ先端を介して弁体８に弁座７からの離脱方向に作用する環状間隙１２側の流体の圧力より高く、この圧力差に基づく作用力が弁体８に弁座７への着座方向に作用するが、この着座方向への作用力よりばね１５のばね力が大きいので、弁体８は弁座７から離脱して球弁保持部材９の保持部９Ｃの窪み９Ｆ内に保持されている。
【００１９】
負荷流路Ａにおける緊急遮断弁Ｃと電磁方向切換弁１８弁との間の配管が破損する（特にホース部分Ａ１で生じやすい）異常事態が、シリンダ１９の上昇作動時に生じると、負荷流路Ａへの流体は破損部分から外部へ流出し、緊急遮断弁Ｃと電磁方向切換弁１９との間の圧力は大きく低下する。このため、シリンダ１９は負荷の作用により下降を始め、ヘッド側室１９Ａからの流体は緊急遮断弁Ｃを貫通孔６の一端開口側から他端開口側へと上昇作動時とは逆方向に流れて破損部分から外部へ流出する。このとき、環状間隙１２側の圧力が大きく低下するので、絞り孔１３Ａ、…、１３Ｆ前後に大きな圧力差が生じ、通過流量が急増するが、この急増した通過流量が瞬時に閉弁流量（絞り孔１３Ａ、…、１３Ｆの開口面積、すなわち絞り孔１３Ａ、…、１３Ｆの個数により用途に応じた最適な仕様に設定する。）に達し、弁体８は絞り孔１３Ａ、…、１３Ｆ前後の大きな圧力差に基づく作用力でばね１５のばね力に抗して瞬時に弁座７に着座し、貫通孔６の一端開口側から他端開口側への流体の流通を阻止し、シリンダ１９は停止して制御を受けることなく急速下降する危険な事態の発生を回避する。
【００２０】
このような異常事態が、シリンダ１９の下降作動時に生じた場合も、前記上昇作動時と同様に、環状間隙１２側の圧力が大きく低下して絞り孔１３Ａ、…、１３Ｆ前後に大きな圧力差が生じ、通過流量が急増するが、弁体８は絞り孔１３Ａ、…、１３Ｆ前後の大きな圧力差に基づく作用力でばね１５のばね力に抗して瞬時に弁座７に着座し、貫通孔６の一端開口側から他端開口側への流体の流通を阻止し、シリンダ１９は停止して制御を受けることなく急速下降する危険な事態の発生を回避する。
【００２１】
また、異常事態が生じない場合であっても、シリンダ１９の上昇作動時にピストンが上昇端に達して緊急遮断弁Ｃよりヘッド側室１９Ａ側でサージ的な圧力上昇が生じたり、シリンダ１９の下降作動時に緊急遮断弁Ｃより電磁方向切換弁１８側でサージ的な圧力低下が生じたりすることがあるが、このようなサージ的な圧力変化により弁体８が弁座７に着座すると、シリンダ１９を下降作動できなくなる。しかし、一実施形態の緊急遮断弁では、流体の圧力を弁体８に弁座７への着座方向に作用する連通孔１４が小孔部１４Ａを有し、この小孔部１４Ａで弁体８に弁座７への着座方向に作用する流体が絞られるので、弁体８がサージ的な圧力変化に直ちに感応して弁座７に着座することを抑制できる。このため、前記の異常事態が生じない場合であってもサージ的な圧力変化により弁体８が弁座７に着座するという誤作動の発生を抑え、シリンダ１９を安定作動できる。
【００２２】
かかる作動で、絞り孔１３Ａ、…、１３Ｆは球弁保持部材９の基部９Ａの内壁９Ｅに軸方向へ貫通しており、絞り孔１３Ａ、…、１３Ｆの個数（一実施形態では６個であるが、閉弁流量の仕様に合わせて絞り孔を１個貫通した球弁保持部材から６個貫通した球弁保持部材までのものを適宜選択して弁本体に組み付ける。）を貫通孔６の一端開口を介して外部から容易に視認できるため、製品完成後の検査時に外部から絞り孔１３Ａ、…、１３Ｆの個数を容易に確認でき、閉弁流量が仕様に合っているか否かを即座に判別することができる。
【００２３】
また、絞り孔１３Ａ、…、１３Ｆを内壁９Ｅに貫通した球弁保持部材９の保持部９Ａは、貫通孔６の一端開口側へ嵌挿しているため、絞り孔としての薄刃オリフィスを弁本体の奥側に位置している従来の緊急遮断弁に比べ、絞り孔１３Ａ、…、１３Ｆの個数を貫通孔６の一端開口を介して外部からより一層視認し易くできる。
【００２４】
さらにまた、貫通孔６の小径孔部６Ｃ側に収装して弁体８を弁座７からの離脱方向に付勢するばね１５を、そのコイル平均径を弁体８の直径より小さくした小径部１５Ａとそのコイル平均径を貫通孔６の内径に近似した大径部１５Ｂとを連設した圧縮コイルばねとしており、貫通孔６を流通する流体はばね１５の小径部１５Ａと大径部１５Ｂとの連設部の線間すきまを通って小径部１５Ａ外周側と大径部１５Ｂ内周側との間を流通し、連設部の線間すきまは径方向に十分大きく取ることができ、流体が圧縮コイルばねの微細な線間すきまを通ることなく外周側を通って流れるようこの外周側に４個の迂回流路を周方向へ等間隔に設けた従来の緊急遮断弁に比べ、弁本体１の内部に軸方向へ貫通する貫通孔６は単一で良く、弁本体１への加工を簡単にできると共に、弁本体１の径方向の大型化を抑制することができる。
【００２５】
さらにまた、ばね１５の大径部１５Ｂと貫通孔６の内周面に設けた止め輪１６との間に、円筒形状のカラー部材１７を介在しているため、カラー部材１７を軸方向寸法の異なる他のカラー部材に変更することで、弁体８を弁座７からの離脱方向に付勢するばね力を調整でき、異常事態の発生により、絞り孔１３Ａ、…、１３Ｆ前後の圧力差に基づく作用力で弁体８をばね１５のばね力に抗して弁座７に着座する閉弁圧力差を、用途に応じた最適な仕様にばね１５を変更することなく設定することができる。
【００２６】
さらにまた、弁本体１の他側面外周には、ねじ部４に近設して他側面に向けて順次縮径するおすシート部５を形成しているため、このおすシート部５に、端部に向けて順次拡径する配管のめすシート部を直接接合することができ、配管のめすシート部を接合するための接続金具を介在することなくできる。なお、弁本体１の一側面外周のねじ部３はシリンダ１９のポートに螺着して直接接続する場合が多いので、ねじ部３に近設しておすシート部を形成していないが、必要に応じて形成しても良い。
【００２７】
図４及び図５は本発明の他の実施形態を示し、一実施形態と同一個所には同符号を付して説明を省略し、異なる個所についてのみ説明する。
貫通孔６の一端開口側に嵌挿した球弁保持部材９の基部９Ａは、自身の円筒状の外径寸法を、貫通孔６に形成の段部６Ａの拡径側の内径寸法に対応して設け、段部６Ａに内壁９Ｅを有する軸方向他端を係合して止め輪１０で弁本体１に固定している。
【００２８】
貫通孔６の小径孔部６Ｃには、内周面の周方向一部を径方向外方に切り欠いて切欠き２０を形成し、切欠き２０は弁体８が弁座７に着座した際にも貫通孔６の大径孔部６Ｂと小径孔部６Ｃとの間を通じさせ、その開口面積は絞り孔１３Ａ、…、１３Ｆの開口面積より十分に小さく設けている。
【００２９】
ばね１５の大径部１５Ｂと貫通孔６の他端開口側の内周面に設けた止め輪１６との間に介在したカラー部材１７Ａは、一実施形態に示したカラー部材１７に比べ、軸方向の長さ寸法を遙かに小さく設け、ばね１５のばね力を弱く調整している。これにより、異常事態の発生で、絞り孔１３Ａ、…、１３Ｆ前後の圧力差に基づく作用力で弁体８をばね１５のばね力に抗して弁座７に着座する閉弁圧力差を、一実施形態のものと比べ、低く設定している。
【００３０】
弁本体１の他側面に開口する貫通孔６の他端には、他側面に向けて順次拡径するめすシート部２１を形成し、めすシート部２１は図示しない端部に向けて順次縮径する配管のおすシート部と直接接合するよう設けている。
【００３１】
そして、図３の使用例において、図１及び図２に示す一実施形態の緊急遮断弁に換えて図４及び図５に示す他の実施形態の緊急遮断弁を用いると、一実施形態で詳述した配管破損の異常事態が生じた場合、一実施形態と同様に弁体８が弁座７に着座し、シリンダ１９の急速降下を阻止する。このとき、流体は弁座７を迂回して切欠き２０の絞り作用のもとに少流量の流通が生じるので、シリンダ１９を微速で安全に下降端まで下降作動できる。
【００３２】
また、シリンダ１９を上昇作動する場合、シリンダ１９のピストンが上昇端に達すると、ヘッド側室１９Ｂ側にサージ的な大きな圧力上昇を生じることがある。この圧力上昇で、連通孔１４の小孔部１４Ａでの絞り作用で弁体８の移動を抑えることができず弁体８が弁座７に着座してしまっても、切欠き２０により通じあうことで貫通孔６の一端開口側と他端開口側での圧力が均圧化するから、弁体８はばね１５のばね力で再び弁座７から離脱でき、弁体８が弁座７に着座したままとなってシリンダ１９を下降作動できないといった事態が防止できる。
【００３３】
そして、一実施形態では、おすシート部５に配管のめすシート部を直接接合することができ、配管のめすシート部を接合するための接続金具を介在することなくできたが、本実施形態では、めすシート部２１に配管のおすシート部を直接接合することができ、配管のおすシート部を接合するための接続金具を介在することなくできる。この他は、一実施形態と同様の効果を得ることができる。
【００３４】
なお、本発明の各実施形態では、球弁保持部材９の保持部９Ｃ先端と弁座７との間に軸方向の間隙を有したが、従来技術として示した実開昭６１−４１９７１号公報に開示される如く、保持部先端を弁座より外周側の壁面に当接し、その保持部先端に環状間隙を弁座に連なさせる排出孔を形成しても良い。この場合、貫通孔６の段部６Ａ及び球弁保持部材９の基部９Ａに有する環状凸部９Ｄは不要となる。
【００３５】
【発明の効果】
このように請求項１にかかる発明では、絞り孔は球弁保持部材の基部内壁に軸方向へ貫通しており、絞り孔の個数を貫通孔の一端開口を介して外部から容易に視認することができるため、緊急遮断弁は、製品完成後の検査時に外部から絞り孔の個数を容易に確認でき、閉弁流量が仕様に合っているか否かを即座に判別することができる。また、絞り孔を内壁に貫通した球弁保持部材の保持部は、貫通孔の一端開口側へ嵌挿しているため、絞り孔としての薄刃オリフィスを弁本体の奥側に位置している従来の緊急遮断弁に比べ、絞り孔の個数を貫通孔の一端開口を介して外部からより一層視認し易くできる。
【００３６】
また、請求項２にかかる発明では、請求項１にかかる発明の効果に加え、貫通孔の小径孔部側に収装して弁体を弁座からの離脱方向に付勢するばねを、そのコイル平均径を弁体の直径より小さくした小径部とそのコイル平均径を貫通孔の内径に近似した大径部とを連設した圧縮コイルばねとしており、貫通孔を流通する流体はばねの小径部と大径部との連設部の線間すきまを通って小径部外周側と大径部内周側との間を流通し、連設部の線間すきまは径方向に十分大きく取ることができ、流体が圧縮コイルばねの微細な線間すきまを通ることなく外周側を通って流れるようこの外周側に４個の迂回流路を周方向へ等間隔に設けた従来の緊急遮断弁に比べ、弁本体の内部に軸方向へ貫通する貫通孔は単一で良く、弁本体への加工を簡単にできると共に、弁本体の径方向の大型化を抑制することができる。
【００３７】
また、請求項３にかかる発明では、請求項１及び請求項２にかかる発明の効果に加え、ばねの大径部と貫通孔の内周面に設けた止め輪との間に、円筒形状のカラー部材を介在しているため、カラー部材を軸方向寸法の異なる他のカラー部材に変更することで、弁体を弁座からの離脱方向に付勢するばね力を調整でき、異常事態の発生により、絞り孔前後の圧力差に基づく作用力で弁体をばねのばね力に抗して弁座に着座する閉弁圧力差を、用途に応じた最適な仕様にばねを変更することなく設定することができる。
【００３８】
また、請求項４にかかる発明では、請求項１にかかる発明の効果に加え、弁本体の他側面外周には、ねじ部に近設して他側面に向けて順次縮径するおすシート部を形成しているため、このおすシート部に、端部に向けて順次拡径する配管のめすシート部を直接接合することができ、配管のめすシート部を接合するための接続金具を介在することなくできる。
【００３９】
また、請求項５にかかる発明では、請求項１にかかる発明の効果に加え、弁本体の他側面に開口する貫通孔の他端には、他側面に向けて順次拡径するめすシート部を形成しているため、このめすシート部に、端部に向けて順次縮径する配管のおすシート部を直接接合することができ、配管のおすシート部を接合するための接続金具を介在することなくできる。
【図面の簡単な説明】
【図１】本発明の一実施形態を示した緊急遮断弁の縦断面図である。
【図２】図１の右側面図である。
【図３】本発明の緊急遮断弁の使用例を示した回路図である。
【図４】本発明の他の実施形態を示した緊急遮断弁の縦断面図である。
【図５】図４の線Ａ−Ａに沿った断面図である。
【符号の説明】
１弁本体
３、４ねじ部
５おすシート部
６貫通孔
６Ｂ大径孔部
６Ｃ小径孔部
７弁座
８弁体
９球弁保持部材
９Ａ基部
９Ｂ連結部
９Ｃ保持部
９Ｅ内壁
１１第２環状間隙
１２環状間隙
１３Ａ、１３Ｂ、１３Ｃ、１３Ｄ、１３Ｅ、１３Ｆ絞り孔
１４連通孔
１５ばね
１５Ａ小径部
１５Ｂ大径部
１６止め輪
１７、１７Ａカラー部材
２１めすシート部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an emergency shutoff valve that shuts off a flow path due to a rapid increase in passage flow rate.
[0002]
[Prior art]
Conventionally, this kind of emergency shut-off valve is disclosed in Japanese Utility Model Laid-Open No. 61-41971. In this case, when the hose, piping, or the like is damaged on the OUT port side as the other end opening side of the through hole, the pressure on the OUT port side drops rapidly, and the ball valve holding member 4 A large pressure difference occurs before and after the thin blade orifice as a single throttle hole, and the passing flow rate flowing through the shut-off valve increases rapidly. The acting force based on the difference is pressed against the spring force of the compression coil spring and instantly sits on the valve seat, blocking the flow from the IN port side to the OUT port side as one end opening side of the through hole. . The valve closing flow rate for blocking the flow from the IN port side to the OUT port side by the ball valve is set according to the number of thin blade orifices drilled in the ball valve holding member, and a plurality of types of ball valves having different numbers of thin blade orifices. One of the holding members is selected as appropriate and assembled to the valve body to obtain the optimum specification according to the application. In addition, four bypass flow paths are arranged at equal intervals in the circumferential direction on the outer peripheral side of the compression coil spring so that the fluid flowing out to the OUT port side flows through the outer peripheral side without passing through the fine gaps between the compression coil springs. Provided.
[0003]
[Problems to be solved by the invention]
However, in such a conventional emergency shut-off valve, since the thin blade orifice is located on the inner side of the valve body and is pierced in the radial direction in the ball valve holding member, the product after the ball valve holding member is assembled to the valve body is completed. During the inspection, it was difficult to visually confirm the number of thin blade orifices from the outside, and it was difficult to confirm whether or not the valve closing flow rate met the specifications.
[0004]
It is an object of the present invention to provide an emergency shut-off valve that can easily check the number of throttle holes from the outside at the time of inspection after product completion and can immediately determine whether or not the valve closing flow rate meets the specifications. It is an issue.
[0005]
[Means for Solving the Problems]
For this reason, the emergency shutoff valve of the present invention penetrates the through hole through which the fluid flows in the axial direction into the inside of the valve body, and opens both ends of the through hole to one side surface and the other side surface of the valve body. Is provided in a stepped shape in which a large-diameter hole and a small-diameter hole are continuously provided inside the valve body, a valve seat is formed in the continuous step, and the large-diameter hole of the through hole is seated on the valve seat. A ball valve holding member that holds a spherical valve body that blocks between the small diameter hole portion and the small diameter hole portion so as to be movable in the axial direction is provided on the large diameter hole portion side of the through hole. A base portion that is inserted into one side opening side that opens to the side surface and is fixed to the valve body, a connecting portion that protrudes inward in the axial direction from the base portion, and a valve seat and an axial direction that are connected to the inner end of the connecting portion And a holding portion that holds the valve body, and the holding portion is located in the large-diameter hole portion of the through hole, and fluid flows between the outer peripheral surface of the through-hole and the inner peripheral surface of the large-diameter hole portion. ring A gap is formed, and the annular gap is connected to the valve seat via the tip of the holding portion, and is connected to the base via a second annular gap formed between the outer peripheral surface of the connecting portion and the inner peripheral surface of the through hole. Has an inner wall that is perpendicular to the axial direction of the through-hole and closes the through-hole, and the inner wall is provided with a throttle hole that penetrates in the axial direction and passes between one end opening of the through-hole and the annular gap. A through hole that allows the pressure of the fluid on the one end opening side of the through hole, which is the front side, to act on the valve body in the seating direction on the valve seat, passes through the connecting portion in the axial direction, and resists the pressure on the front side of the throttle hole after the throttle hole. The pressure of the fluid on the annular gap side is applied to the valve body in the direction of detachment from the valve seat via the tip of the holding portion, and a spring for urging the valve body in the direction of detachment from the valve seat is used as a small diameter of the through hole. Screws for connection to the outer periphery of one side and the other side that are open on both sides of the through hole in the valve body. The made provided.
[0006]
In this case, the spring that encloses the small diameter hole portion of the through-hole and urges the valve body in the direction away from the valve seat has a small diameter portion whose coil average diameter is smaller than the diameter of the valve body and its coil average diameter. Is a compression coil spring in which a large-diameter portion approximating the inner diameter of the through-hole is connected, and the large-diameter portion is pulled out by a retaining ring provided on the inner peripheral surface of the other end opening side that opens to the other side of the valve body of the through-hole. While stopping, you may contact | abut a small diameter part front-end | tip to a valve body. A collar member is interposed between the large diameter portion of the compression coil spring and the retaining ring provided on the inner peripheral surface of the through-hole to adjust the spring force that urges the valve body in the direction away from the valve seat. You may do it.
[0007]
Also, on the outer periphery of the other side of the valve body, there is a male seat part that is close to the threaded part and gradually reduces the diameter toward the other side, and the male seat part is a female pipe that gradually increases in diameter toward the end. You may join directly with a sheet | seat part.
[0008]
In addition, a female seat portion that gradually increases in diameter toward the other side surface is formed at the other end of the through hole that opens on the other side surface of the valve body, and the female seat portion is a male pipe that is gradually reduced in diameter toward the end portion. You may join directly with a sheet | seat part.
[0009]
According to the emergency shutoff valve of the present invention, when the fluid flows from the other end opening side of the through hole to the one end opening side, the fluid on the other end opening side is the valve seat, the tip of the holding portion of the ball valve holding member, the annular shape It flows to one end opening side through the gap, the second annular gap, and the throttle hole penetrating the base inner wall of the ball valve holding member. At this time, since a pressure drop occurs in the throttle hole, the pressure of the fluid on the annular gap side acting on the valve body in the direction of disengagement from the valve seat via the tip of the holding portion of the ball valve holding member is connected to the ball valve holding member. It is higher than the pressure of the fluid on the one end opening side that acts in the seating direction on the valve seat through the communication hole penetrating in the part, and the valve body has an acting force based on the pressure difference before and after the throttle hole and the spring force of the spring. It is detached from the valve seat. In addition, when fluid flows from one end opening side of the through hole to the other end opening side, the fluid on the one end opening side is a throttle hole penetrating the base inner wall of the ball valve holding member, the second annular gap, the annular gap, and the sphere. It flows to the other end opening side via the holding portion tip of the valve holding member and the valve seat. At this time, since a pressure drop occurs in the throttle hole, the pressure of the fluid on the one end opening side acting on the valve body in the seating direction on the valve body via the communication hole of the connecting portion is applied to the valve body via the tip of the holding portion. It is higher than the pressure of the fluid on the annular gap side acting in the direction of separation from the valve seat, and the acting force based on this pressure difference acts on the valve body in the seating direction on the valve seat, but acts in the seating direction on this valve seat Since the spring force of the spring is larger than the acting force, the valve body is detached from the valve seat. When fluid flows from one end opening side of the through hole to the other end opening side and from the other end opening side to the one end opening side, an abnormal situation occurs when the pipe connected to the other end opening side is damaged. The pressure on the annular gap side is greatly reduced, and a large pressure difference is generated before and after the throttle hole, and the passage flow rate increases rapidly. The acting force based on the pressure difference instantly sits on the valve seat against the spring force of the spring and prevents the fluid from flowing from the one end opening side to the other end opening side. The throttle hole penetrates the inner wall of the base portion of the ball valve holding member in the axial direction, and the number of throttle holes can be easily visually recognized from the outside through one end opening of the through hole. For this reason, the emergency shut-off valve can easily check the number of throttle holes from the outside at the time of inspection after product completion, and can immediately determine whether the valve closing flow rate meets the specifications.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
1 and 2, reference numeral 1 denotes a valve body, and a hexagonal tightening operation portion 2 to be engaged with a tool such as a spanner is formed in the center in the axial direction, and the outer periphery of one side surface and the other side surface is formed respectively. The screw parts 3 and 4 for connection are provided, the male sheet part 5 is formed in the vicinity of the screw part 4 provided on the outer periphery of the other side surface, and the diameter of the male sheet part 5 is sequentially reduced toward the other side surface. It is provided so as to be directly joined to the female sheet portion of the pipe whose diameter is gradually increased toward the end portion.
[0011]
6 is a through-hole penetrating in the axial direction inside the valve body 1. Both ends are opened on one side surface and the other side surface of the valve body 1, and one end opening side that opens on one side surface of the valve body 1 has an inner circumference. The surface is expanded in diameter to form a stepped portion 6A. The through-hole 6 is provided in a stepped shape in which a large-diameter hole portion 6B and a small-diameter hole portion 6C are connected in the inside of the valve body 1, and the continuous step portion between the large-diameter hole portion 6B and the small-diameter hole portion 6C is provided with a valve. A seat 7 is formed. A spherical valve body 8 is seated on the valve seat 7 and blocks between the large-diameter hole portion 6B and the small-diameter hole portion 6C of the through-hole 6, and is held by the ball valve holding member 9 so as to be movable in the axial direction. Yes.
[0012]
The ball valve holding member 9 is provided on the large-diameter hole 6B side of the through-hole 6 and includes a base 9A, a connecting part 9B, and a holding part 9C. The base portion 9A is formed in a cylindrical shape and has an annular convex portion 9D projecting radially from the outer peripheral surface at one end in the axial direction, and an inner wall 9E perpendicular to the axial direction at the other axial end. . Then, the base portion 9A is fitted and inserted into one end opening side that opens on one side surface of the valve body 1 of the through hole 6, and the annular convex portion 9D is engaged with the step portion 6A of the through hole 6 so that the retaining ring 10 is connected to the one end opening side. The inner wall 9 </ b> E closes the through hole 6 by being inserted into the through hole 6.
[0013]
The connecting portion 9B protrudes inward in the axial direction from the center of the inner wall 9E of the base portion 9A, and forms a second annular gap 11 through which fluid flows between its outer peripheral surface and the inner peripheral surface of the through hole 6. Yes. The holding part 9C is connected to the inner end of the connecting part 9B, faces the valve seat 7 in the axial direction, and holds the valve body 8 in the recess 9F opening toward the valve seat 7 so as to be movable in the axial direction. There is an axial gap between the tip of the valve seat 7 and the valve seat 7 and an annular gap 12 is formed between the outer peripheral surface of the valve seat 7 and the inner peripheral surface of the large-diameter hole 6B. is doing.
[0014]
The annular gap 12 is continued to the valve seat 7 via the tip of the holding portion 9C, and is continued to the inner wall 9E of the base portion 9A via the second annular gap 11. 13A, 13B, 13C, 13D, 13E, and 13F are throttle holes that pass through the inner wall 9E in the axial direction and pass between one end opening of the through hole 6 and the annular gap 12, and the like around the connecting portion 9B in the circumferential direction, etc. Six pieces are provided at intervals. 14 is a communication hole penetrating in the axial direction inside the connecting portion 9B. One end in the axial direction opens to the inner wall 9E of the base portion 9A, and the other end in the axial direction opens to the bottom surface of the recess 9F of the holding portion 9C. The pressure of the fluid at one end opening side of the through hole 6 which is the front side of the holes 13A,..., 13F is applied to the valve body 8 in the seating direction on the valve seat 7. The communication hole 14 has a small hole portion 14A for constricting fluid at one end that opens to the inner wall 9E of the base portion 9A.
[0015]
In the valve body 8, the pressure of the fluid on the annular gap 12 side, which is the rear side of the throttling holes 13A,..., 13F, against the front pressure of the throttling holes 13A,. It acts in the direction of detachment from A spring 15 biases the valve body 8 in a direction away from the valve seat 7 and is accommodated on the small diameter hole portion 6C side of the through hole 6. The spring 15 is a compression coil spring in which a small diameter portion 15A whose coil average diameter is smaller than the diameter of the valve body 8 and a large diameter portion 15B whose coil average diameter approximates the inner diameter of the through hole 6 is connected. A valve body 1 of the other end of the valve body 1 is opened on the other side of the other end opening side and a retaining ring 16 is provided with a cylindrical collar member 17 to contact the large diameter portion 15B to prevent the small diameter portion 15A. The tip is in contact with the valve body 8. The fluid flowing through the through-hole 6 passes through a sufficiently large gap between the small diameter portion 15A and the large diameter portion 15B of the spring 15 in the radial direction of the connecting portion between the small diameter portion 15A and the large diameter portion 15B. It circulates between the inner circumference side. The collar member 17 adjusts the spring force of the spring 15 by changing to another collar member having a different length in the axial direction.
[0016]
FIG. 3 shows an example of use of the emergency shut-off valve according to the present invention. A fluid is supplied to the head side chamber 19A of the cylinder 19 via the load flow path A by the electromagnetic direction switching valve 18 and the fluid in the rod side chamber 19B flows through the load flow. When the fluid is discharged through the path B, the fluid moves upward, and when the fluid is supplied to the rod side chamber 19B via the load channel B and the fluid in the head side chamber 19A is exhausted via the load channel A, the fluid moves downward. The head side chamber 19A of the cylinder 19 is always loaded downward, and the thread portion 3 is screwed into the port of the cylinder 19 and is directly connected to the load flow path A to the head side chamber 19A. The female seat portion is directly joined and the pipe is connected to the screw portion 4 or the screw portions 3 and 4 are connected so as to be interposed in the middle of the pipe, and the one end opening of the through hole 6 is connected to the head side chamber 19A of the cylinder 19. In addition, the emergency shut-off valve C is installed in a direction that allows the other end opening of the through hole 6 to communicate with the electromagnetic direction switching valve 18. A1 and B1 are hose portions in the load channels A and B.
[0017]
Next, the operation of this configuration will be described based on the usage example of FIG. 3 using the emergency shut-off valve shown in FIGS. 1 and 2.
When the cylinder 19 is lifted and operated in a normal state where there is no abnormality in the load channel A, the emergency shut-off valve C is connected to the inner peripheral side of the large-diameter portion 15B of the spring 15 from the other end opening side of the through hole 6. Clearance between lines of the continuous portion, the outer peripheral side of the small diameter portion 15A of the spring 15, the valve seat 7, the tip of the holding portion 9C of the ball valve holding member 9, the annular gap 12, the second annular gap 11, and the base 9A of the ball valve holding member 9 The fluid flows through one end opening side of the through-hole 6 through the throttle holes 13A, ..., 13F penetrating the inner wall 9E. At this time, since a pressure drop occurs in the throttle holes 13A,..., 13F, the pressure of the fluid on the annular gap 12 side acting on the valve body 8 in the direction away from the valve seat 7 via the tip of the holding portion 9C 14 is higher than the pressure of the fluid on the opening side of one end that acts on the valve body 8 in the seating direction on the valve seat 7 via the valve body 8, and the valve body 8 is caused by the acting force based on this pressure difference and the spring force of the spring 15. The ball valve holding member 9 is held in the recess 9F of the holding portion 9C.
[0018]
Further, when the cylinder 19 is lowered in this normal state, the emergency shutoff valve C is a throttle hole 13A,..., 13F penetrating from the one end opening side of the through hole 6 through the inner wall 9E of the base 9A of the ball valve holding member 9. , Second annular gap 11, annular gap 12, tip of holding part 9 </ b> C of ball valve holding member 9, valve seat 7, outer diameter side of small diameter part 15 </ b> A of spring 15, clearance between lines of connecting part of spring 15, large spring 15 The fluid flows to the other end opening side of the through hole 6 through the inside of the diameter portion 15B. At this time, since a pressure drop occurs in the throttle holes 13A,..., 13F, the pressure of the fluid on the one end opening side acting on the valve body 8 in the seating direction on the valve seat 7 via the communication hole 14 is the tip of the holding portion 9C. The pressure of the fluid on the side of the annular gap 12 acting on the valve body 8 in the direction of detachment from the valve seat 7 via the pressure, and the acting force based on this pressure difference acts on the valve body 8 in the seating direction on the valve seat 7. However, since the spring force of the spring 15 is larger than the acting force in the seating direction, the valve body 8 is detached from the valve seat 7 and is held in the recess 9F of the holding portion 9C of the ball valve holding member 9.
[0019]
If an abnormal situation in which the piping between the emergency shutoff valve C and the electromagnetic direction switching valve 18 in the load flow path A is broken (especially likely to occur in the hose portion A1) occurs during the ascending operation of the cylinder 19, the load flow path A Flows out from the damaged portion to the outside, and the pressure between the emergency shutoff valve C and the electromagnetic direction switching valve 19 is greatly reduced. For this reason, the cylinder 19 begins to descend due to the action of the load, and the fluid from the head side chamber 19A flows through the emergency shut-off valve C from the one end opening side of the through hole 6 to the other end opening side in the reverse direction. It flows out from the damaged part. At this time, since the pressure on the annular gap 12 side is greatly reduced, a large pressure difference is generated before and after the throttling holes 13A,..., 13F, and the passing flow rate increases rapidly. .., 13F is set to an optimum specification according to the application according to the opening area of the holes 13A,..., 13F, that is, the number of throttle holes 13A,. The acting force based on the pressure difference instantly seats on the valve seat 7 against the spring force of the spring 15, prevents the fluid from flowing from one end opening side to the other end opening side of the through hole 6, and the cylinder 19 stops. Therefore, it is possible to avoid the occurrence of a dangerous situation that rapidly descends without being controlled.
[0020]
Even when such an abnormal situation occurs during the lowering operation of the cylinder 19, the pressure on the annular gap 12 side is greatly reduced and a large pressure difference is generated around the throttle holes 13A,. As a result, the passage flow rate rapidly increases, but the valve body 8 is instantly seated on the valve seat 7 against the spring force of the spring 15 by an action force based on a large pressure difference between the throttling holes 13A,. The flow of the fluid from one end opening side to the other end opening side of the cylinder 6 is prevented, and the cylinder 19 is stopped and the occurrence of a dangerous situation in which it rapidly descends without being controlled is avoided.
[0021]
Even if an abnormal situation does not occur, when the cylinder 19 is raised, the piston reaches the rising end and a surge pressure rises from the emergency shutoff valve C on the head side chamber 19A side, or the cylinder 19 is lowered. In some cases, a surge pressure drop may occur on the electromagnetic directional control valve 18 side from the emergency shutoff valve C. When the valve body 8 is seated on the valve seat 7 due to such a surge pressure change, the cylinder 19 is moved. Lowering operation is not possible. However, in the emergency shut-off valve according to the embodiment, the communication hole 14 that applies the fluid pressure to the valve body 8 in the seating direction to the valve seat 7 has the small hole portion 14A. Since the fluid acting in the seating direction on the valve seat 7 is throttled, it is possible to suppress the valve body 8 from being seated on the valve seat 7 immediately in response to a surge pressure change. For this reason, even if the above-mentioned abnormal situation does not occur, the occurrence of a malfunction in which the valve body 8 is seated on the valve seat 7 due to a surge pressure change can be suppressed, and the cylinder 19 can be stably operated.
[0022]
With this operation, the throttle holes 13A,..., 13F penetrate the inner wall 9E of the base portion 9A of the ball valve holding member 9 in the axial direction, and the number of throttle holes 13A,. However, in accordance with the specification of the valve closing flow rate, one from the ball valve holding member penetrating one throttling hole to the ball valve holding member penetrating six is appropriately selected and assembled to the valve body). Since it is easily visible from the outside through the opening, the number of throttle holes 13A,..., 13F can be easily confirmed from the outside during inspection after product completion, and it is immediately determined whether the valve closing flow rate meets the specifications. can do.
[0023]
Further, since the holding portion 9A of the ball valve holding member 9 penetrating the throttle hole 13A,..., 13F through the inner wall 9E is fitted into one end opening side of the through hole 6, a thin blade orifice as a throttle hole is provided on the valve body. Compared to the conventional emergency shut-off valve located on the far side, the number of throttle holes 13A,..., 13F can be more easily seen from the outside through one end opening of the through hole 6.
[0024]
Furthermore, the spring 15 that is housed on the small diameter hole 6C side of the through hole 6 and biases the valve body 8 in the direction away from the valve seat 7 has a small diameter in which the coil average diameter is smaller than the diameter of the valve body 8. The compression coil spring includes a portion 15A and a large-diameter portion 15B whose coil average diameter approximates the inner diameter of the through-hole 6, and the fluid flowing through the through-hole 6 is a small-diameter portion 15A and a large-diameter portion 15B of the spring 15. Through the gap between the lines of the continuous portion between the outer peripheral side of the small diameter portion 15A and the inner peripheral side of the large diameter portion 15B, the gap between the lines of the continuous portion can be sufficiently large in the radial direction, Compared to a conventional emergency shut-off valve in which four bypass flow paths are provided at equal intervals in the circumferential direction so that the fluid flows through the outer circumferential side without passing through the fine line gap of the compression coil spring. The through-hole 6 penetrating in the axial direction inside the main body 1 may be single, and the processing to the valve main body 1 is possible. Simply is possible, it is possible to suppress an increase in the size of the radial direction of the valve body 1.
[0025]
Furthermore, since the cylindrical collar member 17 is interposed between the large-diameter portion 15B of the spring 15 and the retaining ring 16 provided on the inner peripheral surface of the through hole 6, the collar member 17 has an axial dimension. By changing to another different collar member, the spring force for urging the valve body 8 in the direction of detachment from the valve seat 7 can be adjusted, and the pressure difference before and after the throttling holes 13A,. The valve closing pressure difference at which the valve body 8 is seated on the valve seat 7 against the spring force of the spring 15 by the acting force can be set without changing the spring 15 to the optimum specification according to the application.
[0026]
Furthermore, since the male seat portion 5 is formed on the outer periphery of the other side surface of the valve body 1 so as to be close to the screw portion 4 and gradually reduce in diameter toward the other side surface. It is possible to directly join the female sheet portion of the pipe whose diameter is gradually increased toward the pipe without any connection metal fitting for joining the female sheet portion of the pipe. In many cases, the threaded portion 3 on the outer periphery of one side of the valve body 1 is screwed into the port of the cylinder 19 and directly connected thereto, so that a seat portion is not formed close to the threaded portion 3, but is necessary. You may form according to.
[0027]
4 and 5 show another embodiment of the present invention. The same portions as those in the embodiment are denoted by the same reference numerals, description thereof is omitted, and only different portions will be described.
The base portion 9A of the ball valve holding member 9 fitted into one end opening side of the through hole 6 corresponds to its cylindrical outer diameter size to the inner diameter size of the stepped portion 6A formed in the through hole 6 on the larger diameter side. The other end in the axial direction having the inner wall 9E is engaged with the step portion 6A, and is fixed to the valve body 1 with a retaining ring 10.
[0028]
In the small-diameter hole portion 6C of the through hole 6, a part of the inner peripheral surface in the circumferential direction is notched radially outward to form a notch 20, and the notch 20 is formed when the valve body 8 is seated on the valve seat 7. In addition, the through-hole 6 is passed between the large-diameter hole portion 6B and the small-diameter hole portion 6C, and the opening area is sufficiently smaller than the opening areas of the throttle holes 13A,.
[0029]
The collar member 17A interposed between the large-diameter portion 15B of the spring 15 and the retaining ring 16 provided on the inner peripheral surface on the other end opening side of the through hole 6 has a shaft that is more than the collar member 17 shown in the embodiment. The length of the direction is much smaller, and the spring force of the spring 15 is adjusted to be weak. Thereby, in the occurrence of an abnormal situation, the valve closing pressure difference for seating the valve body 8 against the spring force of the spring 15 against the spring force of the spring 15 by the acting force based on the pressure difference before and after the throttling holes 13A,. It is set lower than that of one embodiment.
[0030]
At the other end of the through-hole 6 that opens to the other side of the valve body 1, a female seat portion 21 that is gradually expanded in diameter toward the other side surface is formed, and the female seat portion 21 is gradually reduced in diameter toward an end portion (not shown). It is provided so as to be directly joined to the male seat portion of the piping to be used.
[0031]
In the usage example of FIG. 3, when the emergency shut-off valve of another embodiment shown in FIGS. 4 and 5 is used instead of the emergency shut-off valve of the embodiment shown in FIGS. When the above-described abnormal situation of pipe breakage occurs, the valve body 8 is seated on the valve seat 7 as in the embodiment, and the rapid lowering of the cylinder 19 is prevented. At this time, since the fluid bypasses the valve seat 7 and flows at a small flow rate under the throttle action of the notch 20, the cylinder 19 can be safely lowered to the lower end at a very low speed.
[0032]
Further, when the cylinder 19 is lifted, when the piston of the cylinder 19 reaches the rising end, a large surge pressure increase may occur on the head side chamber 19B side. Even if the valve body 8 is seated on the valve seat 7 due to the pressure increase, the movement of the valve body 8 cannot be suppressed due to the throttling action at the small hole portion 14A of the communication hole 14, but the valve body 8 communicates with the notch 20. As a result, the pressure at the one end opening side and the other end opening side of the through-hole 6 is equalized, so that the valve body 8 can be detached from the valve seat 7 again by the spring force of the spring 15, and the valve body 8 is moved to the valve seat 7. A situation in which the cylinder 19 cannot be lowered while being seated can be prevented.
[0033]
In one embodiment, the female sheet portion of the pipe can be directly joined to the male sheet portion 5 without using a connection fitting for joining the female sheet portion of the pipe. In addition, the male sheet portion of the pipe can be directly joined to the female sheet portion 21, and a connection fitting for joining the male sheet portion of the pipe can be provided. Other than this, the same effects as those of the embodiment can be obtained.
[0034]
In each of the embodiments of the present invention, there is an axial gap between the tip of the holding portion 9C of the ball valve holding member 9 and the valve seat 7. However, Japanese Utility Model Laid-Open No. 61-41971 shown as the prior art. As disclosed in the above, a discharge hole may be formed such that the tip of the holding portion abuts against the wall surface on the outer peripheral side from the valve seat and the annular gap is connected to the valve seat at the tip of the holding portion. In this case, the annular convex portion 9D included in the step portion 6A of the through hole 6 and the base portion 9A of the ball valve holding member 9 is not necessary.
[0035]
【The invention's effect】
Thus, in the invention according to claim 1, the throttle hole penetrates the base inner wall of the ball valve holding member in the axial direction, and the number of throttle holes can be easily visually recognized from the outside through one end opening of the through hole. Therefore, the emergency shut-off valve can easily check the number of throttle holes from the outside at the time of inspection after product completion, and can immediately determine whether the valve closing flow rate meets the specifications. Further, since the holding portion of the ball valve holding member penetrating the throttle hole through the inner wall is fitted into one end opening side of the through hole, a thin blade orifice as a throttle hole is located on the back side of the valve body. Compared to the emergency shut-off valve, the number of throttle holes can be more easily seen from the outside through one end opening of the through hole.
[0036]
Further, in the invention according to claim 2, in addition to the effect of the invention according to claim 1, a spring that encloses the through hole in the small diameter hole portion side and urges the valve body in the direction of detachment from the valve seat, A compression coil spring with a small diameter part whose coil average diameter is smaller than the diameter of the valve body and a large diameter part whose coil average diameter approximates the inner diameter of the through hole is connected, and the fluid flowing through the through hole is the small diameter of the spring. Between the outer diameter side of the small diameter section and the inner diameter side of the large diameter section through the clearance between the connecting sections of the section and the large diameter section, and the clearance between the lines of the connecting section should be sufficiently large in the radial direction. Compared to a conventional emergency shut-off valve in which four bypass channels are provided at equal intervals in the circumferential direction so that the fluid flows through the outer circumferential side without passing through the fine line gap of the compression coil spring. The through hole that penetrates in the axial direction inside the valve body may be a single one, making it easy to process the valve body Both can be suppressed in the size of the radial direction of the valve body.
[0037]
In addition, in the invention according to claim 3, in addition to the effects of the invention according to claims 1 and 2, a cylindrical shape is provided between the large diameter portion of the spring and the retaining ring provided on the inner peripheral surface of the through hole. Since the collar member is interposed, changing the collar member to another collar member with a different axial dimension can adjust the spring force that urges the valve body in the direction of detachment from the valve seat, resulting in an abnormal situation The valve closing pressure difference for seating the valve body against the spring force of the spring against the spring force is set to the optimum specification according to the application without changing the spring. can do.
[0038]
In addition, in the invention according to claim 4, in addition to the effect of the invention according to claim 1, a male seat portion that is provided near the screw portion and is gradually reduced in diameter toward the other side surface is provided on the outer periphery of the other side surface of the valve body. Since it is formed, the female sheet portion of the pipe that gradually increases in diameter toward the end can be directly joined to this male sheet portion, and a connection fitting for joining the female sheet portion of the pipe is interposed. It can be lost.
[0039]
In addition, in the invention according to claim 5, in addition to the effect of the invention according to claim 1, a female seat portion that is gradually expanded in diameter toward the other side surface is provided at the other end of the through hole that opens to the other side surface of the valve body. Because it is formed, it is possible to directly join the male sheet portion of the pipe, which is gradually reduced in diameter toward the end portion, and interpose a fitting for joining the male sheet portion of the pipe. It can be lost.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of an emergency shutoff valve showing an embodiment of the present invention.
FIG. 2 is a right side view of FIG.
FIG. 3 is a circuit diagram showing an example of use of the emergency shutoff valve of the present invention.
FIG. 4 is a longitudinal sectional view of an emergency shut-off valve showing another embodiment of the present invention.
FIG. 5 is a cross-sectional view taken along line AA in FIG.
[Explanation of symbols]
1 valve body
3, 4 thread
5 male seat
6 through holes
6B large diameter hole
6C small diameter hole
7 seats
8-valve
9 ball valve holding member
9A base
9B connecting part
9C holding part
9E inner wall
11 Second annular gap
12 annular gap
13A, 13B, 13C, 13D, 13E, 13F restricting hole
14 communication holes
15 springs
15A small diameter part
15B large diameter part
16 retaining ring
17, 17A color member
21 female seat

Claims

A through-hole through which fluid flows is axially penetrated into the valve body, and both ends of the through-hole are opened on one side and the other side of the valve body, respectively. A spherical shape that is provided in a stepped shape with a small-diameter hole portion, forms a valve seat on the continuous step portion, and sits on the valve seat to block between the large-diameter hole portion and the small-diameter hole portion of the through hole A ball valve holding member that holds the valve body movably in the axial direction is provided on the large-diameter hole side of the through hole, and the ball valve holding member is fitted into one end opening side that opens on one side of the valve body of the through hole. A base that is fixed to the valve body, a connecting portion that protrudes inward in the axial direction from the base, and a holding portion that is connected to the inner end of the connecting portion and faces the valve seat in the axial direction and holds the valve body The holding portion is located in the large-diameter hole portion of the through hole and forms an annular gap through which fluid flows between its outer peripheral surface and the inner peripheral surface of the large-diameter hole portion. It is connected to the valve seat through the end, and is connected to the base through a second annular gap formed between the outer peripheral surface of the connecting portion and the inner peripheral surface of the through hole. The base is orthogonal to the axial direction of the through hole. The inner wall has an inner wall that closes the through hole, and the inner wall is provided with a throttle hole penetrating in the axial direction and passing between the one end opening of the through hole and the annular gap. A communication hole that causes the pressure of the fluid to act on the valve body in the seating direction on the valve seat passes through the connecting portion in the axial direction, and the pressure of the fluid on the annular gap side that is the rear side of the throttle hole against the pressure on the front side of the throttle hole Acting on the valve body in the direction of detachment from the valve seat via the tip of the holding part, and further, a spring for urging the valve body in the direction of detachment from the valve seat is accommodated on the small diameter hole side of the through hole, Is an emergency shutoff valve in which a thread portion for connection is provided on the outer periphery of one side surface and the other side surface where both ends of the through hole are open.

A spring that encloses the small diameter hole portion of the through hole and urges the valve body in the direction away from the valve seat has a small diameter portion whose coil average diameter is smaller than the diameter of the valve body and the coil average diameter of the spring. A compression coil spring with a large-diameter portion approximating the inner diameter of the through-hole, and with a retaining ring provided on the inner peripheral surface of the other end opening side that opens to the other side of the valve body of the through hole, The emergency shut-off valve according to claim 1, wherein the tip of the small diameter portion is in contact with the valve body.

A collar member is interposed between the large diameter portion of the compression coil spring and the retaining ring provided on the inner peripheral surface of the through-hole to adjust the spring force for urging the valve body in the direction away from the valve seat. The emergency shut-off valve according to claim 2, wherein:

On the outer periphery of the other side surface of the valve body, a male seat portion is formed which is close to the screw portion and is gradually reduced in diameter toward the other side surface, and the male seat portion is a female seat portion of the pipe which is gradually increased in diameter toward the end portion. The emergency shutoff valve according to claim 1, wherein the emergency shutoff valve is directly joined to the emergency shutoff valve.

At the other end of the through-hole that opens on the other side of the valve body, a female seat is formed with a diameter gradually increasing toward the other side, and the female seat is a male seat with a pipe that is gradually reduced in diameter toward the end. The emergency shutoff valve according to claim 1, wherein the emergency shutoff valve is directly joined to the emergency shutoff valve.