JP3625449B2 - On-off valve - Google Patents

Description

【００３０】
また背圧力室１３５は、上述のようにピストン１０２内にロッド１０４の軸線方向他端部１２８が挿入されることによって形成されており、ピストン１０２は、背圧力室１３５内の流体から第２方向Ｘ２に向かう供給圧力Ｐ１を、有効的に受ける背受圧面積Ａ４の背受圧面１５６を有する。背受圧面積Ａ４は、背圧力室１３５内の流体から受ける供給圧力Ｐ１が、ピストン１０２を第２方向Ｘ２への力として有効的に働く面積である。本実施の形態では、ピストン１０２は、背圧力室１３５内の流体から第２方向Ｘ２だけでなく第１方向Ｘ１にも供給圧力Ｐ１を受けており、背受圧面積Ａ４は、背圧力室１３５内の流体から第２方向Ｘ２に供給圧力Ｐ１を受ける受圧面積から、ピストン１０２が背圧力室１３５内の流体から第１方向Ｘ１に供給圧力Ｐ１を受ける受圧面積を減算した面積である。
【００３１】
この背受圧面積Ａ４は、ロッド１０４の軸線方向一端部１２８の軸線Ｌ１０に垂直な断面の面積と同一であって、ロッド１０４の軸線方向他端部１３１を除く部分の外径Ｄ２を用いて、次式（２）で表される。
【００３２】
【数２】

【００３３】
弁座１１８の先端部の直径Ｄ１と、ロッド１０４の軸線方向一端部１２８の外径Ｄ２とは同一であって、したがって供給受圧面積Ａ１と背受圧面積Ａ４とは同一である。このようにピストン１０２は、第１圧力室１４４内の流体から供給圧力Ｐ１を第１方向Ｘ１に受ける供給受圧面１５５の供給受圧面積Ａ１と同一の背受圧面積Ａ４を有し、背圧力室１３５内の流体から第２方向Ｘ２に向かう供給圧力Ｐ１を受ける背受圧面１５６を有する。
【００３４】
またピストン１０２は、第２圧力室１５０内の流体から第２方向Ｘ２に向かう排出圧力Ｐ２を、有効的に受ける第１排出受圧面積Ａ３の第１排出受圧面１５７を有する。第１排出受圧面積Ａ３は、第２圧力室１５０内の流体から受ける排出圧力Ｐ２が、ピストン１０２に第２方向Ｘ２への力として有効的に働く面積である。本実施の形態では、ピストン１０２は、第２圧力室１５０、詳細には、排出側空間１４１に開放端部１１６が部分的に第２方向Ｘ２側から臨んでおり、排出側空間１４１の流体からは第２方向Ｘ２にだけ排出圧力Ｐ２を受ける。したがって第１排出受圧面積Ａ３は、ピストン１０２の開放端部１１６の最大外径Ｄ３を直径とする円からロッド１０４の軸線方向他端部１３１を除く部分の断面の面積、すなわち背受圧面積Ａ４を減算した面積であって、次式（３）で表される。
【００３５】
【数３】

【００３６】
またピストン１０２は、第２圧力室１５０内の流体から第１方向Ｘ１に向かう排出圧力Ｐ２を、有効的に受ける第２排出受圧面積Ａ２の第２排出受圧面１５８を有する。第２排出受圧面積Ａ２は、第２圧力室１５０内の流体から受ける排出圧力Ｐ２が、ピストン１０２に第１方向Ｘ１への力として有効的に働く面積である。本実施の形態では、ピストン１０２は、第２圧力室１５０、詳細には、供給側空間の円環状通路１４３の外方側領域１４５に底部１１５が部分的に第１方向Ｘ１側から臨んでおり、前記外方側領域１４５の流体からは第１方向Ｘ１にだけ排出圧力Ｐ２を受ける。したがって第２排出受圧面積Ａ２は、ピストン１０２の供給側空間の円環状通路１４３の外方側領域１４５に臨む部分の最大外径Ｄ４を直径とする円から供給受圧面積Ａ１を減算した面積であって、次式（４）で表される。
【００３７】
【数４】

【００３８】
ピストン１０２の開放端部１１６の最大外径Ｄ３と、ピストン１０２の供給側空間の円環状通路１４３の外方側領域１４５に臨む部分の最大外径Ｄ４とは同一であって、したがって第１排出受圧面積Ａ３と第２排出受圧面積Ａ２とは同一である。このようにピストン１０２は、第２圧力室１５０内の流体から排出圧力Ｐ２を第２方向Ｘ２に受ける第１排出受圧面１５７の第１排出受圧面積Ａ３と同一の第２排出受圧面積Ａ２を有し、第２圧力室１５０内の流体から第１方向Ｘ１に向かう排出圧力Ｐ２を受ける第２排出受圧面１５８を有する。換言すれば、ピストン１０２の底部１１５を除く部分の外周部は、直径Ｄ３（＝Ｄ４）の円筒状に形成される。
【００３９】
また開閉弁１００では、ピストン１０２に働く軸線方向の力の釣り合いは、次式（５）のように表される。
（Ａ１−Ａ４）Ｐ１＋（Ａ２−Ａ３）Ｐ２＋Ｆｓ＝Ｋ（ΔＨ＋Ｚ） …（５）
【００４０】
ここで、Ｋは、ばね部材１０３のばね定数であり、ΔＨは、図１に示されるばね部材１０３の第１位置での自然状態からの撓み量である。またＺは、ピストン１０２の図１に示される第１位置からの第１方向Ｘ１への変位量である。
【００４１】
本実施の形態の開閉弁１００では、上述のようにピストン背圧力室１３５を形成して、ピストン１０２が供給圧力Ｐ１を背受圧面積Ａ４で、第２方向Ｘに受けるように構成し、これによってピストン１０２が第１方向Ｘ１に受ける供給圧力Ｐ１による力と、ピストン１０２が第２方向Ｘ２に受ける供給圧力Ｐ１による力とを釣り合わせて、ピストン１０２に働く供給圧力Ｐ１による軸線方向の力を相殺することができる。従来の構成では、供給圧力を高くすると、安定してピストンを弁座に着座させるために、その供給圧力によってピストンに働く力に抗するような大きさのばね力をピストンに与えるばね力の大きなばね部材を用いる必要があり、ピストンを弁座から離間するときには、このような大きなばね力に抗する大きな電磁力を与えることができるようにソレノイドを大形化しなければならない。本実施の形態の開閉弁１００では、ピストン１０２に働く供給圧力Ｐ１による軸線方向の力が相殺されるので、供給圧力Ｐ１を高くしても、安定してピストン１０２のシート部１４２を弁座１１８に着座させて第１位置に配置するために、ばね部材１０３のばね力を大きくする必要がない。これに伴って、ピストン１０２のシート部１４２を弁座１１８から離間させて第２位置に配置するために、ソレノイド１３２がピストン１０２に与える電磁力を大きくする必要がなく、ソレノイド１０２を小形化することができ、開閉弁１００の半径方向寸法を小さく抑えることができる。
【００４２】
つまり供給受圧面積Ａ１と背受圧面積Ａ４とを同一とする、換言すれば弁座１１８の先端部の直径Ｄ１とロッド１０４の軸線方向他端部１３１を除く部分の外径Ｄ２とを同一とすることによって、上式（５）における左辺第一項を零にする（Ａ１−Ａ４＝０）ことができ、ピストン１０２に働く供給圧力Ｐ１による力をなくすことができる。これに加えてさらに、第１排出受圧面積Ａ３と第２排出受圧面積Ａ２とを同一とする、換言すればピストン１０２の供給側空間の円環状通路１４３の外方側領域１４５に臨む部分の最大外径Ｄ４とピストン１０２の開放端部１１６の最大外径Ｄ３とを同一とすることによって、上式（５）における左辺第二項を零にする（Ａ２−Ａ３＝０）ことができ、ピストン１０２に働く供給圧力Ｐ２による力をもなくすことができる。したがってソレノイド１３２は、ばね部材１０３の第２方向Ｘ２に向かうばね力に抗する電磁力をピストン１０２に与えればよく、ピストン１０２に働く供給圧力Ｐ１および排出圧力Ｐ２による力を考慮する必要がなく、ソレノイド１３２を小形化することができる。
【００４３】
また流量キャパシティ、すなわち最大許容流量を大きくするために、供給圧力Ｐ１を受けるピストン２０１の供給受圧面積Ａ１を大きくしても、背受圧面１５６を供給受圧面積Ａ１と同一の背受圧面積Ａ４にして形成することで、供給圧力Ｐ１に基づいて、ピストン１０２に第１方向Ｘ１に働く力と、ピストン１０２に第２方向に働く力とを釣り合わせて、ピストン１０２に働く供給圧力Ｐ１による軸線方向の力を相殺できる。これによってばね部材１０３が供給ポート１０８と排出ポート１１０とを遮断するためにピストン１０２に与えるばね力を小さくすることができ、これによってソレノイド１３２が供給ポート１０８と排出ポート１１０とを連通するためにピストン１０２に与える電磁力を大きくすることがない。
【００４４】
またロッド１０４を設けて、ピストン１０２内に部分的に挿入する構成とすることによって、簡単な構成によって、背圧力室１３５を形成し、上述の効果が得られる開閉弁１００を容易に実現することができる。さらにピストン１０２とロッド１０４との間のピストン内空間１３６を流体が流下する通路として利用することによって、ピストン１０２に空間１４０の領域１４４と空間１４１とを連通するための軸線方向に延びる通路を穿設する必要がなく、構成が簡単であり、複雑な加工を必要としないので、容易に製造することができる。また通路の穿設に伴なうピストン１０２の強度低下がないので、ピストン１０２の肉厚（半径方向寸法）を小さく抑えることができ、これによっても、開閉弁１００の半径方向寸法を小さくすることができる。もちろんピストン１０２に空間１４０の領域１４４と空間１４１とを連通するための軸線方向に延びる通路を穿設する構成も、本発明に含まれることは言うまでもない。
【００４５】
このような開閉弁１００は、たとえば消防士が火災現場などで背負う酸素を収容したタンクなどの高圧タンクに設け、高圧タンク内の酸素を外部に排出するための開閉弁として用いることができる。このような高圧タンクに内蔵化して用いる場合、高圧タンクは、強度の観点から半径方向寸法を小さくする必要があり、上述のように半径方向寸法を小さく抑えることができる開閉弁１００は、好適である。
【００４６】
上述の実施の形態は、本発明の例示に過ぎず、本発明の範囲内で構成を変更することができる。たとえばハウジング１０１とロッド１０４とは一体に形成されてもよい。また本実施の形態では、開閉駆動手段は、ばね部材１０３およびソレノイド１３２を含んで構成するとしたが、これに限ることなく、ピストン１０２に軸線方向の駆動力を与えることができる構成であればよい。また用途は、上述の消防士が背負うタンク以外の高圧タンクに設けてもよく、たとえば電気自動車などに搭載される燃料電池を構成するためのガスを収容するタンクに設けるようにしてもよい。またタンク以外の流体圧装置に設けるようにしてもよい。流体は、気体であってもよいし、液体であってもよい。
【００４７】
図４は、開閉弁１００と減圧弁２０とを組合わせた弁装置２００を示す断面図である。弁装置２００は、開閉弁１００によって供給ポート１０８から供給された流体の排出および排出の停止を切換えるとともに、減圧弁２０によって供給された流体を減圧しながら外部に排出する。
【００４８】
図５は、減圧弁２０を拡大して示す断面図である。減圧弁２０は、一次側から二次側に流体が流下する流路に介在され、供給される一次圧力（以後「一次圧」と略して表記することがある）Ｐ３の流体を、一次圧Ｐ３よりも低い二次圧（以後「二次圧」と略して表記することがある）Ｐ４に減圧して排出する弁である。この減圧弁２０は、ハウジング２１と、ピストン２２と、ばね部材２３と、ロッド２４とを含んで構成され、ハウジング２１、ピストン２２、ばね部材２３およびロッド２４は、相互に同軸に設けられ、それぞれの軸線は、減圧弁２０の軸線Ｌ１と一致している。
【００４９】
ハウジング２１は、有底円筒状のハウジング本体２５と、ハウジング本体２５の開口端部２６に内挿されて装着されるキャップ部材２７とを有する。キャップ部材２７は、ハウジング本体２５に対して、軸線Ｌ１まわりに回転して、軸線Ｌ１沿って螺進および螺退自在に螺着され、軸線方向の位置を調節自在に設けられる。ハウジング本体２５の内周部とキャップ部材２７の外周部との間は、周方向全周にわたってシールが達成されている。
【００５０】
キャップ部材２７には、軸線Ｌ１に沿って挿通する一次ポート２８が形成され、ハウジング本体２５の底部２９には、軸線Ｌ１に沿って挿通する二次ポート３０が形成される。このようにハウジング２１には、軸線方向一端部３１に一次ポート２８が形成され、軸線方向他端部３２に二次ポート３０が形成される。
【００５１】
またキャップ部材２７には、ハウジング２１の内方に向けて、軸線方向一方Ｘ１へ先細状に突出し、一次ポート２８を外囲するように、周方向全周に延びる円環状の突起片３８が形成される。ここで軸線方向一方Ｘ１は、ハウジング２１の軸線方向一端部３１から他端部３２に向かう方向である。
【００５２】
ピストン２２は、有底円筒状に形成され、軸線方向一端部である底部３５側をハウジング２１の軸線方向一端部３１側に配置し、軸線方向他端部である開放端部３６側をハウジング２１の軸線方向他端部３２側に配置して、ハウジング２１内に保持される。この状態でピストン２２は、軸線Ｌ１に沿って、軸線方向一方Ｘ１およびその反対の軸線方向他方Ｘ２へ変位自在である。
【００５３】
ハウジング２１の軸線方向両端部３１，３２間の軸線方向中間部３９には、半径方向内方に突出して周方向全周に延びるフランジ状の内向き凸部４０が形成され、この内向き凸部４０の内周部に、ピストン２２の底部３５および開口端部３６間の軸線方向中間部３７における外周部が、シールを達成した状態で当接している。またピストン２２の開口端部３６には、半径方向外方に突出して周方向全周に延びるフランジ状の外向き凸部４１が形成され、この外向き凸部４１の外周部が、ハウジング２１の軸線方向中間部３９における内向き凸部４０よりも軸線方向他端部３２寄りの部分の内周部に、シールを達成した状態で当接している。
【００５４】
ばね手段であるばね部材２３は、圧縮コイルばねであり、ハウジング２１とピストン２２とが半径方向に間隔をあけて形成される円環状のばね収容空間４３に配置されて、ピストン２２に外嵌される状態でハウジング２１内に設けられる。ばね収容空間４３は、内向き凸部４０と外向き凸部４１との間に形成され、ハウジング２１に形成される大気開放孔４４によって大気に開放されている。
【００５５】
ばね部材２３は、軸線方向一端部４５が内向き凸部４０に支持され、軸線方向他端部４６が外向き凸部４１に支持される。このばね部材２３によって、ハウジング２１に対して軸線方向一方Ｘ１に向かうばね力を、ピストン２２に与えることができる。
【００５６】
ロッド２４は、大略的に円柱状であって、ハウジング２１に保持され、軸線方向一端部４８側の部分をピストン２２内に、ピストン２２に対して、軸線Ｌ１に沿って、軸線方向一方Ｘ１および軸線方向他方Ｘ２へ変位自在に挿入されている。このロッド２４は、少なくとも軸線方向他端部５１がピストン２２から突出した状態で設けられ、この軸線方向他端部５１は、残余の部分に比べて外径が大きく形成されており、ピストン２２の開口端部３６を軸線方向に支持することができるように構成されている。
【００５７】
ハウジング２１の軸線方向一端部３２、したがってハウジング本体２５の底部２９には、開口端部２６に向かって（軸線方向他方Ｘ２に）凹となる嵌合凹所５０が形成される。ロッド２４は、この嵌合凹所５０に軸線方向他端部５１が嵌まり込んで保持されている。
【００５８】
ロッド２４の軸線方向一端部４８は、その外周部がピストン２２の内周部にシールを達成した状態で当接し、ピストン２２とロッド２４との間に背圧力室５５が形成される。またロッド２４は、軸線方向一端部４８を除く部分であって、ピストン２２内に挿入される部分の外周部は、ピストン２２の内周部との間に半径方向に間隔をあけており、円環状のピストン内空間５６が形成される。
【００５９】
このような減圧弁２０では、上述のようにピストン２２の外周部が、２箇所において、ハウジング２１の内周部に、周方向全周にわたってシールを達成した状態で当接している。ハウジング２１内には、ハウジング２１とピストン２２との間に、内向き凸部４０よりも軸線方向他方Ｘ２側に、有底筒状の空間６０が形成されるとともに、外向き凸部４１よりも軸線方向一方Ｘ１側に、環状の空間６１が形成される。
【００６０】
ピストン２２は、軸線方向一端部の端面部分に、周方向全周に延びる特殊樹脂から成るシート部６２が形成され、このシート部６２がキャップ部材２７の突起片３８に軸線方向に対向して、周方向全周に延びる円環状のオリフィス６３が形成される。空間６０は、オリフィス６３を介して連なる２つの領域６４，６５を有する。オリフィス６３よりも半径方向内方側となる領域は、一次ポート２８に連なる一次圧力室６４である。
【００６１】
またピストン２２には、軸線方向中間部３７のロッド２４の軸線方向一端部４８に当接する部分よりも開口端部３６寄りの部分に、内外に挿通する挿通孔６７が形成される。この挿通孔６７によって、空間６０のオリフィスよりも半径方向外方側の領域６５と、ピストン内空間５６とが連通される。
【００６２】
またロッド２４の軸線方向他端部５１およびその付近には、軸線方向他端部５１において、軸線方向一方Ｘ１に開口するとともに半径方向外方に開口し、軸線方向他端部５１付近のピストン２２内に挿入される部分において、半径方向外方に開口する連通孔６８が形成される。この連通孔６８によって、二次側空間６１と、ピストン内空間５６とが連通されるとともに、これら二次側空間６１およびピストン内空間５６が、二次ポート３０に連通される。オリフィス６３よりも半径方向外方側の領域６５、空間６１、ピストン内空間５６、挿通孔６７および連通孔６８を含んで、二次ポート３０に連なる二次圧力室７０が構成される。
【００６３】
またピストン２２の底部３５には、この底部３５を軸線Ｌ１に沿って挿通する透孔７１が形成されている。この透孔７１によって、一次圧力室６４と、背圧力室５５とが連通される。
【００６４】
このように減圧弁２０では、ピストン２２は、ハウジング２１内を、オリフィス６３によって連なる一次圧力室６４と二次圧力室７０とに仕切る。一次ポート２８に供給される流体は、一次圧力室６４からオリフィス６３を通過して二次圧力室７０に、具体的には、一次側空間の領域６５に流下し、挿通孔６７、ピストン内空間５６および連通孔６８を経て、二次ポート３０に流下し、二次ポート３０から吐出される。このように減圧弁２０を流体が流下するとき、ピストン２２は、ロッド２４の軸線方向他端部５１との間に軸線方向に間隔をあける。
【００６５】
流体がオリフィス６３を通過するとき、流体の圧力が低下される。言い換えるならば、流体は、一次圧力室６４から、オリフィス６３を通過することによって減圧されて、二次圧力室７０に流下する。したがって一次ポート２８、一次圧力室６４および背圧力室５５内の流体は、一次圧Ｐ３を有し、二次ポート３０および二次圧力室７０内の流体は、一次圧Ｐ３よりも低い二次圧Ｐ４を有する。
【００６６】
図６は、減圧弁２０を簡略化して示す断面図である。図５を併せて参照して、ピストン２２は、一次圧力室６４の流体から軸線方向一方Ｘ１に向かう一次圧Ｐ３を、有効的に受ける一次受圧面積Ｂ１の一次受圧面７５を有する。一次受圧面積Ｂ１は、ピストン２２が一次圧力室６４内の流体から軸線方向一方Ｘ１に一次圧Ｐ３を受ける受圧面積から、ピストン２２が一次圧力室６４内の流体から軸線方向他方Ｘ２に一次圧Ｐ３を受ける受圧面積を減算した面積であって、一次圧力室６４内の流体から受ける一次圧Ｐ３が、ピストン２２を軸線方向一方Ｘ１への力として有効的に働く面積である。
【００６７】
ピストン２２は、一次圧力室６４に軸線方向一方Ｘ１側からだけ臨んでおり、一次圧力室６４の流体から軸線方向一方Ｘ１にだけ一次圧Ｐ３を受ける。したがって一次受圧面積Ｂ１は、シート部６２と協働してオリフィス６３を形成する突起片３８の先端部の直径Ｅ１を用いて、次式（６）で表される。
【００６８】
【数５】

【００６９】
また背圧力室５５は、上述のようにピストン２２内にロッド２４の軸線方向一端部４８が挿入されることによって形成されており、ピストン２２は、背圧力室５５内の流体から軸線方向他方Ｘ２に向かう一次圧Ｐ３を、有効的に受ける背受圧面積Ｂ４の背受圧面７６を有する。背受圧面積Ｂ４は、ピストン２２が背圧力室５５内の流体から軸線方向他方Ｘ２に一次圧Ｐ３を受ける受圧面積から、ピストン２２が背圧力室５５内の流体から軸線方向一方Ｘ１に一次圧Ｐ３を受ける受圧面積を減算した面積であって、背圧力室５５内の流体から受ける一次圧Ｐ３が、ピストン２２を軸線方向他方Ｘ２への力として有効的に働く面積である。この背受圧面積Ｂ４は、ロッド２４の軸線方向一端部４８の軸線Ｌ１に垂直な断面の面積と同一であって、ロッド２４の軸線方向一端部４８の外径Ｅ２を用いて、次式（７）で表される。
【００７０】
【数６】

【００７１】
突起片３８の先端部の直径Ｅ１と、ロッド２４の軸線方向一端部４８の外径Ｅ２は、同一であって、したがって一次受圧面積Ｂ１と有効背受圧面積Ｂ４とは同一である。このようにピストン２２は、一次圧力室６４内の流体から一次圧Ｐ３を軸線方向一方Ｘ１に受ける一次受圧面７５の一次受圧面積Ｂ１と同一の有効背受圧面積Ｂ４を有し、背圧力室５５内の流体から軸線方向他方Ｘ２に向かう一次圧Ｐ３を受ける背受圧面７６を有する。
【００７２】
またピストン２２は二次圧力室７０内の流体から軸線方向他方Ｘ２に向かう二次圧Ｐ４を有効的に受ける受圧面積Ｂ３−Ｂ２の二次受圧面８０を有する。
【００７３】
また、ピストン２２が二次圧力室７０内の流体から軸線方向他方Ｘ２に二次圧Ｐ４を受ける受圧面積Ｂ３は、ピストン２２の二次側空間６１に臨む部分の最大外径である外向き凸部４１の外径Ｅ３を直径とする円からロッド２４の軸線方向他端部４８の軸線Ｌ１に垂直な断面の面積（＝Ｂ４）を減算した面積であって、次式（８）で表される。
【００７４】
【数７】

【００７５】
ピストン２２が二次圧力室７０内の流体から軸線方向一方Ｘ１に二次圧Ｐ４を受ける受圧面積Ｂ２は、ピストン２２の一次側空間のオリフィス６３の外方側領域６５に臨む部分の最大外径Ｅ４を直径とする円から一次受圧面積Ｂ１を減算した面積であって、次式（９）で表される。
【００７６】
【数８】

【００７７】
図７は、減圧弁２０の二次圧Ｐ４を示すグラフであって、図７（１）は、一次圧Ｐ３と二次圧Ｐ４との関係を示し、図７（２）は、流量Ｑと二次圧Ｐ４との関係を示す。減圧弁２０では、ピストン２２に働く力の釣り合いから、二次圧Ｐ４は、次式（１０）のように表される。
【００７８】
【数９】

【００７９】
ここで、Ｋａは、ばね部材２３のばね定数であり、ΔＨａは、図６に示されるばね部材２３の初期状態での自然状態からの撓み量である。またＺａは、ピストン２２の図６に示される初期状態からの軸線方向他方Ｘ２への変位量であって、式（１０）で表されるように、一次圧Ｐ３と、減圧弁２０を流下する流体の流量Ｑとの関数で表される。
【００８０】
以上のように上述の減圧弁２０では、上述のように背圧力室５５を形成して、ピストン２２が一次圧Ｐ３を背受圧面積Ｂ４で、軸線方向他方Ｘ２に受けるように構成し、これによってピストン２２が軸線方向一方Ｘ１に受ける一次圧Ｐ３による力と、ピストン２２が軸線方向他方Ｘ２に受ける一次圧Ｐ３による力とを釣り合わせることができる。つまり一次受圧面積Ｂ１と背受圧面積Ｂ４とを同一とし、上式（１０）における右辺第二項の分子を零にする（Ｂ１−Ｂ４＝０）ことができ、一次圧Ｐ３が変化しても、式（１０）における右辺第二項の値を一定値（＝０）として、右辺第一項だけが変化する式となるようにすることができる。したがって図７（１）に示すように、ピストン２２に背受圧面７６を形成しない、従来の構成に比べて、一次圧Ｐ３の変化量ΔＰ３に対する二次圧Ｐ４の変化量ΔＰ４を大幅に低減することができる。
【００８１】
また減圧弁２０では、流量キャパシティ、すなわち最大許容流量を大きくするために、突起片３８の先端部の直径Ｅ１を大きくして、一次受圧面積Ｂ１が大きくなっても、背受圧面積Ｂ４を大きくすれば、一次圧Ｐ３の変化量ΔＰ３に対する二次圧Ｐ４の変化量ΔＰ４を小さく抑えることができる。したがって最大許容流量を大きくするために、ピストン２２に背受圧面７６を形成しない場合のように、ピストン２２の二次圧Ｐ４を軸線方向他方Ｘ２に受ける受圧面積Ｂ３を大きくする必要がなく、ピストン２２の最大外径である外向き凸部４１の外径Ｅ３を大きくする必要がない。したがって減圧弁２０の半径方向寸法を小さく抑えることができる。このように流量Ｑに拘わらず、減圧弁２０の半径方向寸法を小さく抑えた上、一次圧Ｐ３の変化量ΔＰ３に対する二次圧Ｐ４の変化量ΔＰ４を小さく抑えることができる。
【００８２】
またロッド２４を設けて、ピストン２２内に部分的に挿入する構成とすることによって、簡単な構成によって、背圧力室５５を形成し、上述の効果が得られる減圧弁２０を容易に実現することができる。さらにピストン２２とロッド２４との間のピストン内空間５６を流体が流下する通路として利用することによって、ピストン２２に空間６０の領域６４と空間６１とを連通するための軸線方向に延びる通路を穿設する必要がなく、構成が簡単であり、複雑な加工を必要としないので、容易に製造することができる。また通路の穿設に伴なうピストン２２の強度低下がないので、ピストン２２の肉厚（半径方向寸法）を小さく抑えることができ、これによっても、減圧弁２０の半径方向寸法を小さくすることができる。もちろんピストン２２に空間６０の領域６４と空間６１とを連通するための軸線方向に延びる通路を穿設する構成も、本発明に含まれることは言うまでもない。
【００８３】
また本実施の形態では、突起片３８が形成されるキャップ部材２７を、ハウジング本体２５に対する軸線方向に位置を調節できるので、突起片３８とピストン２２のシート部６２との軸線方向間隔を調節することができ、一次圧Ｐ３に対する二次圧Ｐ４の減圧比を調節することができる。
【００８４】
上述の減圧弁２０の説明は一例に過ぎず、構成を変更することができる。たとえばハウジング２１とロッド２４とは一体に形成されてもよい。
【００８５】
図４に示す弁装置２００は、開閉弁１００の軸線方向他端部１１２を減圧弁２０のキャップ部材２７に内挿されて連結されて構成される。このとき、開閉弁１００の軸線Ｌ１０と減圧弁２０の軸線Ｌ１とが同軸となるとともに、開閉弁１００の軸線方向他端部１１２と減圧弁２０のキャップ部材２７は、シール部材を配設してシールが達成される。またこのとき、開閉弁１００の排出ポート１１０と減圧弁２０の一次ポート２８とは連通しており、排出圧力Ｐ２と一次圧Ｐ３とは等しい。
【００８６】
このような弁装置２００において、開閉弁１００の供給ポート１０８から供給される供給圧力Ｐ１の流体は、開閉弁１００によって排出ポート１１０への排出を制御され、排出ポート１１０から排出された一次圧Ｐ３の流体は、減圧弁２０の一次ポート２８に供給され、減圧弁２０によって二次圧Ｐ４に減圧されて、二次ポート３０から排出される。
【００８７】
このような弁装置２００は、たとえば消防士が火災現場などで背負う酸素を収容したタンクなどの高圧タンクに設け、高圧タンク内の酸素を、減圧しながら外部に排出するための弁装置として用いることができる。このような高圧タンクに内蔵化して用いる場合、高圧タンクは、強度の観点から半径方向寸法を小さくする必要があり、上述のように半径方向寸法を小さく抑えることができる弁装置２００は、極めて好適である。
【００８８】
上述の弁装置２００の説明は一例に過ぎず、構成を変更することができる。また用途は、上述の消防士が背負うタンク以外の高圧タンクに設けてもよく、たとえば電気自動車などに搭載される燃料電池を構成するためのガスを収容するタンクに設けるようにしてもよい。またタンク以外の流体圧装置に設けるようにしてもよい。流体は、気体であってもよいし、液体であってもよい。
【００８９】
【発明の効果】
請求項１記載の本発明によれば、供給ポートおよび排出ポートがハウジングの軸線方向両端部に形成され、ハウジング内に供給ポートから排出ポートに流体が流下する通路が形成される開閉弁において、ピストン内にロッドを挿入するだけの簡単な構成によって、供給圧力を高くしても、開閉駆動手段が供給ポートと排出ポートとの連通および遮断を制御するために、ピストンに与える軸線方向の駆動力を大きくすることなく、最大許容流量を大きくすることができる。しかも開閉弁の半径方向寸法を小さくすることができる。
【００９０】
請求項２記載の本発明によれば、ピストンに供給ポートと排出ポートとを連通させるための通路を別途に穿設する必要がなく、構成が簡単であり、複雑な加工を必要としないので、容易に製造することができる。また通路の穿設に伴なうピストンの強度低下がないので、ピストンの肉厚（半径方向寸法）を小さく抑えることができ、これによっても、開閉弁の半径方向寸法を小さくすることができる。
【図面の簡単な説明】
【図１】本発明の実施の一形態の開閉弁１００のピストン１０２が第１位置に配置される状態を示す断面図である。
【図２】開閉弁１００のピストン１０２が第２位置に配置される状態を示す断面図である。
【図３】開閉弁１００を簡略化して示す断面図である。
【図４】開閉弁１００と減圧弁２０とを組合わせた弁装置２００を示す断面図である。
【図５】減圧弁２０を拡大して示す断面図である。
【図６】減圧弁２０を簡略化して示す断面図である。
【図７】減圧弁２０の二次圧Ｐ４を示すグラフであって、図７（１）は、一次圧Ｐ３と二次圧Ｐ４との関係を示し、図７（２）は、流量Ｑと二次圧Ｐ４との関係を示す。
【図８】従来の技術の開閉弁１を示す断面図である。
【符号の説明】
１００ 開閉弁
１０１ ハウジング
１０２ ピストン
１０３ ばね部材
１０４ ロッド
１０８ 供給ポート
１１０ 排出ポート
１１８ 弁座
１３２ ソレノイド
１３５ 背圧力室
１４４ 第１圧力室
１５０ 第２圧力室
１５５ 供給受圧面
１５６ 背受圧面[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an on-off valve provided, for example, in a fluid pressure device.
[0002]
[Prior art]
FIG. 8 is a cross-sectional view showing a conventional on-off valve 1. The on-off valve 1 is configured such that a piston 3 is held in a housing 2 so as to be freely displaceable in the axial direction, and a spring member 4 is provided to apply a spring force toward the piston 3 toward one axial direction x1. A supply port 5 and a discharge port 6 are formed in the housing 2, and a valve seat 7 is formed surrounding the supply port 5. In this way, the inside of the housing 2 is partitioned into a first pressure chamber 10 that is continuous with the supply port 5 and a second pressure chamber 11 that is continuous with the discharge port 6. Further, the on-off valve 1 applies an electromagnetic force toward the other axial direction x2 to the piston 3 made of a ferromagnetic material outside the housing 2, and cooperates with the spring member 4 to communicate between the supply port 5 and the discharge port 6. A solenoid 9 for controlling the shutoff is provided.
[0003]
In a state in which the solenoid 9 is not energized, the piston 3 is provided with a spring force toward the axial direction one x1 by the spring member 4, and is disposed at a blocking position where the seat portion 8 is seated on the valve seat 7, and the supply port 5 And the discharge port 6 are blocked. In a state where the solenoid 9 is energized, the piston 3 is arranged at a separated position where the seat portion 8 is separated from the valve seat 7 by the electromagnetic force applied to the other axial direction x 2 by the solenoid 9. It communicates with the discharge port 6. At this time, the fluid having the supply pressure p <b> 1 supplied to the supply port 5 can be discharged from the discharge port 6.
[0004]
[Problems to be solved by the invention]
In order to shut off the supply port 5 and the discharge port 6, it is necessary to stably seat the seat portion 8 of the piston 3 on the valve seat 7 of the housing 2. For this purpose, the on-off valve 1 needs to be configured such that the relationship of the force acting on the piston 3 satisfies the following equation (a) when the piston 3 is disposed at the shut-off position.
k · Δh> a1 · p1 (a)
[0005]
In the above formula (a), a1 is a pressure receiving area that receives the supply pressure p1 in the other axial direction x2 of the piston 3, k is a spring constant of the spring member 4, and Δh is a position where the piston 3 is located at the blocking position. This is the amount of bending of the spring member 4 with respect to the natural state. The left side of the above formula (a) is the force acting on the piston 3 in one axial direction x1, that is, the spring force k · Δh by the spring member 4, and the right side is the force acting on the piston 3 in the other axial direction x2, ie, supply. The force a1 · p1 due to the fluid having the supply pressure p1 supplied to the port 5. In the on-off valve 1, the piston 3 is configured to receive the supply pressure p <b> 1 only at the other axial direction x <b> 2 on the pressure receiving surface of the area a <b> 1. Therefore, in order to stably seat the seat portion 8 on the valve seat 7, supply is performed so that the spring force k · Δh of the spring member 4 increases as the supply pressure p 1 of the fluid supplied to the supply port 5 increases. It must be set corresponding to the pressure p1. On the other hand, in order to drive the piston 3 toward the other in the axial direction x2, a large solenoid 9 that can apply an electromagnetic force against the large spring force to the piston 3 is required.
[0006]
In order to increase the flow capacity of the on-off valve 1, that is, the maximum allowable flow rate, it is necessary to increase the diameter of the valve seat 7. When the diameter of the valve seat 7 is increased, the pressure receiving area a1 is increased, and it is necessary to increase the spring force as shown in the equation (a). As a result, it is necessary to increase the electromagnetic force applied to the piston 3 by the solenoid 9 toward the other axial direction x2. That is, a larger solenoid 9 is required.
[0007]
SUMMARY OF THE INVENTION An object of the present invention is to provide an on-off valve that can reduce the driving force of an on-off driving means that controls communication and disconnection between a supply port and a discharge port even when the supply pressure is increased or the maximum allowable flow rate is increased. That is.
[0008]
[Means for Solving the Problems]
The present invention according to claim 1 includes: (a) a housing in which a supply port is formed at one end in the axial direction and a discharge port is formed at the other end in the axial direction;
(B) a rod that is held on the housing by disposing one end in the axial direction on the one end side in the axial direction of the housing;
(C) a piston formed in a bottomed cylindrical shape,
(C1) The bottom portion is disposed on one end side in the axial direction of the housing, and the rod is inserted, and is held so as to be displaceable in the axial direction with respect to the housing and the rod,
(C2) The supply port and the discharge port are communicated and blocked by the displacement in the axial direction,
(C3) partitioning the housing into a first pressure chamber connected to the supply port and a second pressure chamber connected to the discharge port, and forming a back pressure chamber held at the supply pressure between the rod and the rod;
(C4) A supply pressure receiving surface of a supply pressure receiving area that receives a supply pressure directed in one axial direction from the fluid in the first pressure chamber; A back pressure receiving surface that is received by area is formed,
(D) open / close drive means for applying axial driving force to the piston to control communication and disconnection between the supply port and the discharge port;
(E) The on-off valve is characterized in that a passage in which a fluid flows from the supply port to the discharge port is formed in the housing.
[0009]
According to the present invention, a supply port is formed at one end of the housing in the axial direction, a discharge port is formed at the other end in the axial direction of the housing, and a passage in which fluid flows from the supply port to the discharge port is formed in the housing. Has been. The housing is provided with a bottomed cylindrical piston with the bottom disposed on one end side in the axial direction of the housing. By providing this piston, the inside of the housing is partitioned into a first pressure chamber and a second pressure chamber. Further, a rod is provided by being held by the housing, and this rod is inserted into the piston. By inserting the rod into the piston, a back pressure chamber is formed between the rod and the piston.
Thus, the supply pressure receiving surface, the back pressure receiving surface, and the discharge pressure receiving surface are formed on the piston. The area of the supply pressure receiving surface and the area of the back pressure receiving surface are the same, and the supply pressure receiving surface and the back pressure receiving surface receive supply pressure from opposite directions in the axial direction. Thus, based on the supply pressure, the force acting on the piston in one axial direction and the force acting on the piston in the other axial direction can be balanced to cancel the axial force due to the supply pressure acting on the piston. Therefore, even if the supply pressure is increased, it is not necessary to increase the axial driving force applied to the piston in order for the opening / closing drive means to control the communication and disconnection between the supply port and the discharge port.
[0010]
Furthermore, in order to increase the maximum allowable flow rate, even if the supply pressure receiving area of the piston that receives the supply pressure is increased, by forming a back pressure receiving surface of the same back pressure receiving area as the supply pressure receiving area, based on the supply pressure, The force acting on the piston in one axial direction and the force acting on the other in the piston axial direction can be balanced to cancel the axial force due to the supply pressure acting on the piston. As a result, the opening / closing drive means controls the communication and blocking between the supply port and the discharge port, so there is no need to increase the axial driving force applied to the piston. Since it is not necessary to increase the driving force applied to the piston, the opening / closing driving means can be reduced in size, and the radial dimension of the opening / closing valve can be kept small.
Thus, by providing a bottomed cylindrical piston in the housing and inserting the rod into the piston, the supply port and the discharge port are open and closed formed at both ends in the axial direction of the housing, and the radial direction An on-off valve that can keep the size small and increase the maximum allowable flow rate can be easily realized.
[0011]
According to the second aspect of the present invention, the rod is a portion excluding one end portion in the axial direction and the outer peripheral portion of the portion inserted into the piston is spaced apart from the inner peripheral portion of the piston in the radial direction. An annular piston inner space is formed between the piston and the rod, and this piston inner space forms part of a passage through which fluid flows from the supply port to the discharge port.
[0012]
According to the present invention, an annular piston inner space is formed between the piston and the rod, and the fluid can flow from the supply port to the discharge port using the piston inner space as a passage. Accordingly, it is not necessary to separately provide a passage for connecting the supply port and the discharge port to the piston, the structure is simple, and complicated processing is not required, so that the piston can be easily manufactured. Further, since there is no decrease in the strength of the piston due to the drilling of the passage, the thickness (radial dimension) of the piston can be kept small, and this can also reduce the radial dimension of the pressure reducing valve.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a cross-sectional view showing a state in which the piston 102 of the on-off valve 100 according to the embodiment of the present invention is disposed at the first position, and FIG. 2 is a diagram illustrating the state where the piston 102 of the on-off valve 100 is disposed at the second position. It is sectional drawing which shows the state performed. The on-off valve 100 is a valve that is interposed in a flow path through which fluid flows from the supply side to the discharge side, and controls discharge of the fluid supplied from the supply side to the discharge side. The on-off valve 100 includes a housing 101, a piston 102, a spring member 103, a rod 104, and a solenoid 180. The housing 101, the piston 102, the spring member 103, and the rod 104 are coaxial with each other. Each axis line is coincident with the axis line L10 of the on-off valve 100.
[0014]
The housing 101 has a bottomed cylindrical first housing body 105, and is mounted on the opening end portion 106 of the first housing body 105 so as to be mounted, and includes a nonmagnetic portion 160 made of a nonmagnetic material and a magnetic portion 161 made of a magnetic material. And a cap member 107 made of a nonmagnetic material. The cap member 107 is inserted into and attached to one end 114 in the axial direction of the second housing body 113. Sealing is achieved between the outer peripheral portion of the opening end portion 106 of the first housing body 105 and the inner peripheral portion of the second axial end portion 122 of the second housing body 113 over the entire circumference. Further, a seal is achieved over the entire circumference in the circumferential direction between the inner circumferential portion of the axial end portion 114 of the second housing body 113 and the outer circumferential portion of the cap member 107. A flange-shaped inward convex portion 120 that protrudes inward in the radial direction and extends in the entire circumferential direction is formed at an axially intermediate portion between the bottom portion 109 and the opening end portion 106 of the first housing body 105.
[0015]
The cap member 107 is formed with a supply port 108 that is inserted along the axis L10, and the bottom 109 of the first housing body 105 is formed with a discharge port 110 that is inserted along the axis L10. As described above, the housing 101 is provided with the supply port 108 at the one axial end 111 and the discharge port 110 at the other axial end 112.
[0016]
The cap member 107 is formed with an annular valve seat 118 that protrudes in the first direction X1 toward the inside of the housing 101 and extends around the entire circumference in the circumferential direction so as to surround the supply port 108. Is done. Here, the first direction X <b> 1 is a direction from the one end 111 in the axial direction of the housing 101 toward the other end 112.
[0017]
The piston 102 is made of a ferromagnetic material and is formed in a bottomed cylindrical shape. The bottom 115 side which is one end in the axial direction is disposed on the one end 111 side in the axial direction of the housing 101 and the open end which is the other end in the axial direction. The portion 116 side is disposed on the other axial end portion 112 side of the housing 101 and is held by the second housing body 113. In this state, the piston 102 is displaceable in the first direction X1 and the opposite second direction X2 along the axis L10.
[0018]
The rod 104 is generally cylindrical, and is held by the housing 101. A portion on the axial end portion 128 side is in the piston 102, with respect to the piston 102, along the axis L10, in the first direction X1 and It is inserted so as to be displaceable in the second direction X2. The rod 104 is provided in a state where at least the other axial end portion 131 protrudes from the piston 102. A fitting recess 130 that is concave toward the opening end portion 106 (in the second direction X2) is formed at the other axial end portion 112 of the housing 101, that is, at the bottom portion 109 of the first housing body 105. The rod 104 is held with the other axial end 131 fitted in the fitting recess 130.
[0019]
One end portion 128 in the axial direction of the rod 104 abuts the outer peripheral portion of the rod 104 on the inner peripheral portion of the piston 102 in a sealed state, and a back pressure chamber 135 is formed between the piston 102 and the rod 104. The rod 104 is a portion excluding the one end portion 128 in the axial direction, and the outer peripheral portion of the portion inserted into the piston 102 is radially spaced from the inner peripheral portion of the piston 102, and is substantially An annular piston inner space 136 is formed. An annular space 141 is formed in the first housing body 105 on the first direction X1 side with respect to the inward convex portion 120.
[0020]
In the piston 102, a seat portion 142 made of a special resin extending in the entire circumferential direction is formed on an end surface portion of one end portion in the axial direction, and the seat portion 142 is opposed to the valve seat 118 of the cap member 107 in the axial direction. An annular annular passage 143 extending in the entire circumference is formed (see FIG. 2). When the piston 102 is disposed at the first position shown in FIG. 1, the seat portion 142 is seated on the valve seat 118 of the cap member 107, and at this time, a seal is achieved between the seat portion 142 and the valve seat 118. . The space 140 has two regions 144 and 145 that are connected via an annular passage 143. A region on the radially inner side with respect to the annular passage 143 is a first pressure chamber 144 connected to the supply port 108.
[0021]
Further, a groove 121 extending in the axial direction and recessed inward in the radial direction is formed in the outer peripheral portion excluding the open end portion 116 of the piston 102. In the housing 101, a space 140 surrounded by the inner peripheral surface of the second housing body 113 and the groove 121 of the piston 102 is formed. Furthermore, an insertion hole 147 that is inserted in the radial direction is formed in a portion closer to the opening end portion 116 than a portion that abuts on the axial end portion 128 of the rod 104 of the piston 102. The insertion hole 147 allows the space 140 and the piston internal space 136 to communicate with each other.
[0022]
A communication hole 148 that opens in the first direction X1 and opens outward in the radial direction is formed at and near the other axial end 131 of the rod 104. By this communication hole 148, the discharge side space 141 and the piston inner space 136 are communicated with the discharge port 110. A second pressure chamber 150 connected to the discharge port 110 includes a region 145 radially outward from the annular passage 143, a space 140, a piston inner space 136, an insertion hole 147, a discharge side space 141, and a communication hole 148. Composed.
[0023]
In addition, a through hole 151 is formed in the bottom portion 115 of the piston 102 so as to pass through the bottom portion 115 along the axis L10. The first pressure chamber 144 and the back pressure chamber 135 communicate with each other through the through hole 151.
[0024]
As described above, in the on-off valve 100, the piston 102 partitions the inside of the housing 101 into the first pressure chamber 144 and the second pressure chamber 150 that are connected by the annular passage 143. When the piston 102 as shown in FIG. 2 is disposed at the second position, the fluid supplied to the supply port 108 passes from the first pressure chamber 144 through the annular passage 143 to the second pressure chamber 150, specifically. Specifically, it flows down to the region 145 of the supply side space, flows down to the discharge port 110 through the space 140, the insertion hole 147, the piston inner space 136, the discharge side space 141 and the communication hole 148, and is discharged from the discharge port 110. The
[0025]
The spring member 103 is a compression coil spring, and the first housing body 105 and the piston 102 are disposed in an annular spring accommodating space 123 formed at an interval in the axial direction, and are externally fitted to the rod 104. It is provided in the housing 101 in a state. The spring accommodating space 123 is formed between the inward convex portion 120 of the first housing body 105 and the open end portion 116 of the piston 102. The spring member 103 has one axial end 125 supported by the open end 116 of the piston 102 and the other axial end 126 supported by the inward convex portion 120. With this spring member 103, a spring force in the second direction X <b> 2 can be applied to the piston 102 with respect to the housing 101.
[0026]
The solenoid 132 includes a substantially cylindrical coil bobbin 133 made of a ferromagnetic material and a coil 134 wound around the coil bobbin 133 around the axis L10. In a state where the drive current I is not applied to the coil 134 of the solenoid 132, the piston 102 causes the seat portion 142 of the piston 102 to move the cap member 107 as shown in FIG. 1 by the spring force of the spring member 103 in the second direction X2. The valve seat 118 is disposed at a first position. When the driving current I is applied to the coil 134 of the solenoid 132, the piston 102 is displaced in the first direction X1 by the electromagnetic force in the first direction X1 against the spring force in the second direction X2 of the spring member 103. As shown in FIG. 2, the seat portion 142 of the piston 102 is disposed at a second position away from the valve seat 118 of the cap member 107. By supplying and stopping supply of the drive current I to the solenoid 132 in this way, the solenoid 132 and the spring member 103 cooperate to apply electromagnetic force and spring force to the piston 102 to displace and supply the piston 102. Communication and blocking between the port 108 and the discharge port 110 can be controlled. In the present embodiment, the opening / closing driving means includes a spring member 103 and a solenoid 132, and the driving force includes a spring force by the spring member 103 and an electromagnetic force by the solenoid 132.
[0027]
FIG. 3 is a cross-sectional view showing the on-off valve 100 in a simplified manner. 1 and 2 together, the piston 102 has a supply pressure receiving surface 155 having a supply pressure receiving area A1 that effectively receives the supply pressure P1 from the fluid in the first pressure chamber 144 in the first direction X1. . The supply pressure receiving area A1 is an area where the supply pressure P1 received from the fluid in the first pressure chamber 144 effectively acts on the piston 102 as a force in the first direction X1. In the present embodiment, the piston 102 receives the supply pressure P1 from the fluid in the first pressure chamber 144 only in the first direction X1, and the area thereof is the supply pressure receiving area A1.
[0028]
The piston 102 faces the first pressure chamber 144 only from the first direction X1 side, and receives the supply pressure P1 from the fluid in the first pressure chamber 144 only in the first direction X1. The pressure receiving area that receives the supply pressure P1 from the fluid in the chamber 144 in the second direction X2 is zero. Accordingly, the supply pressure receiving area A <b> 1 is expressed by the following equation (1) using the diameter D <b> 1 of the tip of the valve seat 118 that forms the annular passage 143 in cooperation with the seat portion 142.
[0029]
[Expression 1]

[0030]
The back pressure chamber 135 is formed by inserting the other axial end 128 of the rod 104 into the piston 102 as described above, and the piston 102 is separated from the fluid in the back pressure chamber 135 in the second direction. A back pressure receiving surface 156 having a back pressure receiving area A4 that effectively receives the supply pressure P1 toward X2 is provided. The back pressure receiving area A4 is an area where the supply pressure P1 received from the fluid in the back pressure chamber 135 effectively acts as a force in the piston 102 in the second direction X2. In the present embodiment, the piston 102 receives the supply pressure P1 from the fluid in the back pressure chamber 135 not only in the second direction X2 but also in the first direction X1, and the back pressure receiving area A4 is within the back pressure chamber 135. This is an area obtained by subtracting the pressure receiving area where the piston 102 receives the supply pressure P1 in the first direction X1 from the fluid in the back pressure chamber 135 from the pressure receiving area where the supply pressure P1 is received in the second direction X2 from the fluid.
[0031]
This back pressure receiving area A4 is the same as the area of the cross section perpendicular to the axis L10 of the axial end portion 128 of the rod 104, and using the outer diameter D2 of the portion excluding the axial end portion 131 of the rod 104, It is represented by the following formula (2).
[0032]
[Expression 2]

[0033]
The diameter D1 of the distal end portion of the valve seat 118 is the same as the outer diameter D2 of the axial end portion 128 of the rod 104, and therefore the supply pressure receiving area A1 and the back pressure receiving area A4 are the same. Thus, the piston 102 has a back pressure receiving area A4 that is the same as the supply pressure receiving area A1 of the supply pressure receiving surface 155 that receives the supply pressure P1 from the fluid in the first pressure chamber 144 in the first direction X1. The back pressure receiving surface 156 that receives the supply pressure P1 in the second direction X2 from the fluid inside is provided.
[0034]
Further, the piston 102 has a first discharge pressure receiving surface 157 having a first discharge pressure receiving area A3 that effectively receives the discharge pressure P2 from the fluid in the second pressure chamber 150 in the second direction X2. The first discharge pressure receiving area A3 is an area where the discharge pressure P2 received from the fluid in the second pressure chamber 150 effectively acts on the piston 102 as a force in the second direction X2. In the present embodiment, the piston 102 has the second pressure chamber 150, specifically, the discharge side space 141 with the open end portion 116 partially facing from the second direction X 2 side, and from the fluid in the discharge side space 141. Receives the discharge pressure P2 only in the second direction X2. Therefore, the first discharge pressure receiving area A3 is the cross sectional area of the portion excluding the other end 131 in the axial direction of the rod 104 from the circle having the maximum outer diameter D3 of the open end 116 of the piston 102, that is, the back pressure receiving area A4. The subtracted area is expressed by the following equation (3).
[0035]
[Equation 3]

[0036]
Further, the piston 102 has a second discharge pressure receiving surface 158 having a second discharge pressure receiving area A2 that effectively receives the discharge pressure P2 from the fluid in the second pressure chamber 150 in the first direction X1. The second discharge pressure receiving area A2 is an area where the discharge pressure P2 received from the fluid in the second pressure chamber 150 effectively acts on the piston 102 as a force in the first direction X1. In the present embodiment, the piston 102 has the bottom 115 partially facing the second pressure chamber 150, specifically, the outer side region 145 of the annular passage 143 in the supply side space from the first direction X1 side. The discharge pressure P2 is received from the fluid in the outer side region 145 only in the first direction X1. Therefore, the second discharge pressure receiving area A2 is an area obtained by subtracting the supply pressure receiving area A1 from a circle having the maximum outer diameter D4 of the portion facing the outer side region 145 of the annular passage 143 in the supply side space of the piston 102 as a diameter. Is expressed by the following equation (4).
[0037]
[Expression 4]

[0038]
The maximum outer diameter D3 of the open end 116 of the piston 102 is the same as the maximum outer diameter D4 of the portion facing the outer side region 145 of the annular passage 143 in the supply side space of the piston 102, and therefore the first discharge The pressure receiving area A3 and the second discharge pressure receiving area A2 are the same. Thus, the piston 102 has the same second discharge pressure receiving area A2 as the first discharge pressure receiving area A3 of the first discharge pressure receiving surface 157 that receives the discharge pressure P2 from the fluid in the second pressure chamber 150 in the second direction X2. And a second discharge pressure receiving surface 158 that receives the discharge pressure P2 from the fluid in the second pressure chamber 150 in the first direction X1. In other words, the outer peripheral portion of the portion excluding the bottom portion 115 of the piston 102 is formed in a cylindrical shape having a diameter D3 (= D4).
[0039]
In the on-off valve 100, the balance of axial force acting on the piston 102 is expressed by the following equation (5).
(A1-A4) P1 + (A2-A3) P2 + Fs = K (ΔH + Z) (5)
[0040]
Here, K is a spring constant of the spring member 103, and ΔH is a deflection amount from the natural state at the first position of the spring member 103 shown in FIG. Z is the amount of displacement of the piston 102 in the first direction X1 from the first position shown in FIG.
[0041]
In the on-off valve 100 of the present embodiment, the piston back pressure chamber 135 is formed as described above, and the piston 102 is configured to receive the supply pressure P1 in the second direction X at the back pressure receiving area A4. The force due to the supply pressure P1 received by the piston 102 in the first direction X1 and the force due to the supply pressure P1 received by the piston 102 in the second direction X2 are balanced to cancel the axial force due to the supply pressure P1 acting on the piston 102. can do. In the conventional configuration, when the supply pressure is increased, in order to stably seat the piston on the valve seat, a large spring force is applied to the piston so as to resist the force acting on the piston by the supply pressure. It is necessary to use a spring member, and when the piston is separated from the valve seat, the solenoid must be enlarged so that a large electromagnetic force can be applied against such a large spring force. In the on-off valve 100 of the present embodiment, the axial force due to the supply pressure P1 acting on the piston 102 is offset, so even if the supply pressure P1 is increased, the seat portion 142 of the piston 102 can be stably moved to the valve seat 118. Therefore, it is not necessary to increase the spring force of the spring member 103. Accordingly, since the seat portion 142 of the piston 102 is separated from the valve seat 118 and disposed at the second position, it is not necessary to increase the electromagnetic force applied to the piston 102 by the solenoid 132, and the solenoid 102 is reduced in size. Therefore, the radial dimension of the on-off valve 100 can be kept small.
[0042]
That is, the supply pressure receiving area A1 and the back pressure receiving area A4 are made the same, in other words, the diameter D1 of the distal end portion of the valve seat 118 and the outer diameter D2 of the portion excluding the other axial end 131 of the rod 104 are made the same. Thus, the first term on the left side in the above equation (5) can be made zero (A1-A4 = 0), and the force due to the supply pressure P1 acting on the piston 102 can be eliminated. In addition to this, the first discharge pressure receiving area A3 and the second discharge pressure receiving area A2 are made the same, in other words, the maximum of the portion facing the outer side region 145 of the annular passage 143 in the supply side space of the piston 102. By making the outer diameter D4 and the maximum outer diameter D3 of the open end 116 of the piston 102 the same, the second term on the left side in the above equation (5) can be made zero (A2-A3 = 0). The force due to the supply pressure P2 acting on 102 can be eliminated. Therefore, the solenoid 132 only needs to apply an electromagnetic force against the spring force of the spring member 103 in the second direction X2 to the piston 102, and it is not necessary to consider the force due to the supply pressure P1 and the discharge pressure P2 acting on the piston 102. The solenoid 132 can be miniaturized.
[0043]
Further, in order to increase the flow capacity, that is, the maximum allowable flow rate, even if the supply pressure receiving area A1 of the piston 201 that receives the supply pressure P1 is increased, the back pressure receiving surface 156 is set to the same back pressure receiving area A4 as the supply pressure receiving area A1. Therefore, the axial direction of the supply pressure P1 acting on the piston 102 is balanced between the force acting on the piston 102 in the first direction X1 and the force acting on the piston 102 in the second direction based on the supply pressure P1. The power of can be offset. As a result, the spring force applied to the piston 102 by the spring member 103 to shut off the supply port 108 and the discharge port 110 can be reduced, whereby the solenoid 132 allows the supply port 108 and the discharge port 110 to communicate with each other. The electromagnetic force applied to the piston 102 is not increased.
[0044]
Further, by providing the rod 104 and partially inserting it into the piston 102, the back pressure chamber 135 can be formed with a simple configuration, and the on-off valve 100 that can achieve the above-described effect can be easily realized. Can do. Further, by using the piston internal space 136 between the piston 102 and the rod 104 as a passage through which fluid flows, a passage extending in the axial direction for communicating the region 144 of the space 140 and the space 141 with the piston 102 is formed. It is not necessary to install, the configuration is simple, and no complicated processing is required, and therefore it can be manufactured easily. Further, since the strength of the piston 102 does not decrease due to the drilling of the passage, the thickness (radial dimension) of the piston 102 can be kept small, and this also makes the radial dimension of the on-off valve 100 small. Can do. Needless to say, a configuration in which a passage extending in the axial direction for communicating the region 144 of the space 140 and the space 141 to the piston 102 is included in the present invention.
[0045]
Such an on-off valve 100 is provided in a high-pressure tank such as a tank containing oxygen carried by a firefighter at a fire site or the like, and can be used as an on-off valve for discharging oxygen in the high-pressure tank to the outside. When used in such a high-pressure tank, the high-pressure tank needs to have a small radial dimension from the viewpoint of strength, and the on-off valve 100 that can keep the radial dimension small as described above is suitable. is there.
[0046]
The above-described embodiment is merely an example of the present invention, and the configuration can be changed within the scope of the present invention. For example, the housing 101 and the rod 104 may be integrally formed. In the present embodiment, the opening / closing drive means includes the spring member 103 and the solenoid 132. However, the present invention is not limited to this, and any structure may be used as long as it can apply the axial driving force to the piston 102. . In addition, the use may be provided in a high-pressure tank other than the tank carried by the firefighter described above, and may be provided, for example, in a tank that contains a gas for constituting a fuel cell mounted on an electric vehicle or the like. Moreover, you may make it provide in fluid pressure apparatuses other than a tank. The fluid may be a gas or a liquid.
[0047]
FIG. 4 is a cross-sectional view showing a valve device 200 in which the on-off valve 100 and the pressure reducing valve 20 are combined. The valve device 200 switches between discharging and stopping the discharge of the fluid supplied from the supply port 108 by the opening / closing valve 100 and discharging the fluid supplied by the pressure reducing valve 20 to the outside while reducing the pressure.
[0048]
FIG. 5 is an enlarged cross-sectional view of the pressure reducing valve 20. The pressure reducing valve 20 is interposed in a flow path where the fluid flows down from the primary side to the secondary side, and supplies the supplied primary pressure P3 (hereinafter sometimes abbreviated as “primary pressure”) P3 to the primary pressure P3. It is a valve that discharges by reducing the pressure to a lower secondary pressure (hereinafter sometimes abbreviated as “secondary pressure”) P4. The pressure reducing valve 20 includes a housing 21, a piston 22, a spring member 23, and a rod 24. The housing 21, the piston 22, the spring member 23, and the rod 24 are provided coaxially with each other. Is coincident with the axis L1 of the pressure reducing valve 20.
[0049]
The housing 21 has a bottomed cylindrical housing main body 25 and a cap member 27 that is inserted into the opening end portion 26 of the housing main body 25 and attached thereto. The cap member 27 rotates about the axis L1 with respect to the housing main body 25, and is screwed and screwed along the axis L1 so that the position in the axial direction can be adjusted. Sealing is achieved between the inner periphery of the housing body 25 and the outer periphery of the cap member 27 over the entire circumference.
[0050]
A primary port 28 is formed in the cap member 27 so as to be inserted along the axis L1. A secondary port 30 is formed in the bottom 29 of the housing body 25 so as to be inserted along the axis L1. As described above, the housing 21 is formed with the primary port 28 at the one axial end 31 and the secondary port 30 at the other axial end 32.
[0051]
The cap member 27 is formed with an annular projecting piece 38 that protrudes in the axial direction toward the inside X1 of the housing 21 and extends in the circumferential direction so as to surround the primary port 28. Is done. Here, one axial direction X <b> 1 is a direction from one axial end 31 of the housing 21 toward the other end 32.
[0052]
The piston 22 is formed in a bottomed cylindrical shape, and the bottom 35 side, which is one axial end, is disposed on the one axial end 31 side of the housing 21, and the open end 36, which is the other axial end, is disposed on the housing 21. It is arrange | positioned at the axial direction other end part 32 side, and is hold | maintained in the housing 21. FIG. In this state, the piston 22 is displaceable along the axis L1 to one axial direction X1 and the other opposite axial direction X2.
[0053]
A flange-shaped inward convex portion 40 that protrudes inward in the radial direction and extends in the entire circumferential direction is formed at the axial intermediate portion 39 between the axial end portions 31, 32 of the housing 21, and this inward convex portion. The outer peripheral portion of the axial intermediate portion 37 between the bottom portion 35 and the open end portion 36 of the piston 22 is in contact with the inner peripheral portion of the piston 22 in a state where a seal is achieved. The opening end 36 of the piston 22 is formed with a flange-like outward convex portion 41 protruding outward in the radial direction and extending in the entire circumferential direction. The outer peripheral portion of the outward convex portion 41 is formed on the housing 21. The axially intermediate portion 39 is in contact with the inner peripheral portion of the portion closer to the other end 32 in the axial direction than the inward convex portion 40 in a state where a seal is achieved.
[0054]
The spring member 23, which is a spring means, is a compression coil spring, and is disposed in an annular spring accommodating space 43 in which the housing 21 and the piston 22 are spaced apart from each other in the radial direction. Provided in the housing 21. The spring accommodating space 43 is formed between the inward convex portion 40 and the outward convex portion 41, and is opened to the atmosphere by an atmospheric opening hole 44 formed in the housing 21.
[0055]
In the spring member 23, one end 45 in the axial direction is supported by the inward convex portion 40, and the other end 46 in the axial direction is supported by the outward convex portion 41. The spring member 23 can apply a spring force to the piston 22 in the axial direction X1 with respect to the housing 21.
[0056]
The rod 24 is substantially cylindrical, and is held by the housing 21. A portion on the axial direction one end portion 48 side is in the piston 22, and the axial direction L1 with respect to the piston 22 along the axial line X1 and It is inserted so as to be displaceable in the other axial direction X2. The rod 24 is provided in a state where at least the other end portion 51 in the axial direction protrudes from the piston 22, and the other end portion 51 in the axial direction has a larger outer diameter than the remaining portion. The opening end portion 36 is configured to be supported in the axial direction.
[0057]
A fitting recess 50 that is concave toward the opening end portion 26 (in the other axial direction X2) is formed in one end portion 32 of the housing 21 in the axial direction, and thus in the bottom portion 29 of the housing body 25. The rod 24 is held with the other axial end 51 fitted in the fitting recess 50.
[0058]
One end 48 in the axial direction of the rod 24 abuts on the inner peripheral portion of the piston 22 with the outer peripheral portion thereof achieving a seal, and a back pressure chamber 55 is formed between the piston 22 and the rod 24. Further, the rod 24 is a portion excluding the one end portion 48 in the axial direction, and the outer peripheral portion of the portion inserted into the piston 22 is radially spaced from the inner peripheral portion of the piston 22. An annular piston inner space 56 is formed.
[0059]
In the pressure reducing valve 20 as described above, the outer peripheral portion of the piston 22 is in contact with the inner peripheral portion of the housing 21 at two locations in a state where a seal is achieved over the entire circumference in the circumferential direction. In the housing 21, a bottomed cylindrical space 60 is formed between the housing 21 and the piston 22 on the other side X <b> 2 in the axial direction from the inward convex portion 40, and more than the outward convex portion 41. An annular space 61 is formed on the one side X1 in the axial direction.
[0060]
The piston 22 is formed with a sheet portion 62 made of a special resin extending in the entire circumferential direction on an end surface portion of one end portion in the axial direction, and the sheet portion 62 is opposed to the protruding piece 38 of the cap member 27 in the axial direction. An annular orifice 63 extending in the entire circumference is formed. The space 60 has two regions 64 and 65 that are connected via an orifice 63. A region that is radially inward from the orifice 63 is a primary pressure chamber 64 that continues to the primary port 28.
[0061]
Further, the piston 22 is formed with an insertion hole 67 that is inserted into the inside and outside of the piston 22 at a portion closer to the opening end portion 36 than a portion that contacts the one axial end portion 48 of the rod 24 of the axial direction intermediate portion 37. By this insertion hole 67, the region 65 located radially outward from the orifice of the space 60 and the piston internal space 56 are communicated with each other.
[0062]
The other end 51 in the axial direction of the rod 24 and the vicinity thereof are opened at one axial direction X1 and opened radially outward at the other axial end 51, and the piston 22 near the other axial end 51 is opened. A communication hole 68 that opens radially outward is formed in the portion inserted into the inside. Through the communication hole 68, the secondary side space 61 and the piston inner space 56 communicate with each other, and the secondary side space 61 and the piston inner space 56 communicate with the secondary port 30. A secondary pressure chamber 70 connected to the secondary port 30 is configured including a region 65 radially outward from the orifice 63, a space 61, a piston inner space 56, an insertion hole 67, and a communication hole 68.
[0063]
A through hole 71 is formed in the bottom portion 35 of the piston 22 so as to pass through the bottom portion 35 along the axis L1. The primary pressure chamber 64 and the back pressure chamber 55 communicate with each other through the through hole 71.
[0064]
Thus, in the pressure reducing valve 20, the piston 22 partitions the inside of the housing 21 into the primary pressure chamber 64 and the secondary pressure chamber 70 that are connected by the orifice 63. The fluid supplied to the primary port 28 flows from the primary pressure chamber 64 through the orifice 63 to the secondary pressure chamber 70, specifically, to the region 65 of the primary side space. It flows down to the secondary port 30 through 56 and the communication hole 68 and is discharged from the secondary port 30. Thus, when the fluid flows down the pressure reducing valve 20, the piston 22 is spaced apart in the axial direction from the other axial end portion 51 of the rod 24.
[0065]
As the fluid passes through the orifice 63, the pressure of the fluid is reduced. In other words, the fluid is depressurized from the primary pressure chamber 64 by passing through the orifice 63 and flows down to the secondary pressure chamber 70. Therefore, the fluid in the primary port 28, the primary pressure chamber 64 and the back pressure chamber 55 has a primary pressure P3, and the fluid in the secondary port 30 and the secondary pressure chamber 70 has a secondary pressure lower than the primary pressure P3. P4.
[0066]
FIG. 6 is a cross-sectional view showing the pressure reducing valve 20 in a simplified manner. Referring also to FIG. 5, the piston 22 has a primary pressure receiving surface 75 of a primary pressure receiving area B <b> 1 that effectively receives the primary pressure P <b> 3 from the fluid in the primary pressure chamber 64 toward the one axial direction X <b> 1. The primary pressure receiving area B1 is the pressure receiving area where the piston 22 receives the primary pressure P3 in the axial direction one X1 from the fluid in the primary pressure chamber 64, and the primary pressure P3 in the other axial direction X2 from the fluid in the primary pressure chamber 64. The primary pressure P3 received from the fluid in the primary pressure chamber 64 is an area that effectively acts as a force on the piston 22 in the axial direction X1.
[0067]
The piston 22 faces the primary pressure chamber 64 only from one axial direction X1 side, and receives the primary pressure P3 from the fluid in the primary pressure chamber 64 only in one axial direction X1. Accordingly, the primary pressure receiving area B <b> 1 is expressed by the following equation (6) using the diameter E <b> 1 of the tip of the protruding piece 38 that forms the orifice 63 in cooperation with the seat portion 62.
[0068]
[Equation 5]

[0069]
Further, the back pressure chamber 55 is formed by inserting the one axial end 48 of the rod 24 into the piston 22 as described above, and the piston 22 is separated from the fluid in the back pressure chamber 55 in the other axial direction X2. The back pressure receiving surface 76 having a back pressure receiving area B4 that effectively receives the primary pressure P3 toward the back. The back pressure area B4 is determined from the pressure receiving area where the piston 22 receives the primary pressure P3 in the other axial direction X2 from the fluid in the back pressure chamber 55, and the primary pressure P3 in the axial direction X1 from the fluid in the back pressure chamber 55. The primary pressure P3 received from the fluid in the back pressure chamber 55 is an area that effectively acts as a force on the piston 22 in the other axial direction X2. This back pressure receiving area B4 is the same as the area of the cross section perpendicular to the axis L1 of the axial end portion 48 of the rod 24, and using the outer diameter E2 of the axial end portion 48 of the rod 24, the following equation (7 ).
[0070]
[Formula 6]

[0071]
The diameter E1 of the tip end portion of the protruding piece 38 and the outer diameter E2 of the axial end portion 48 of the rod 24 are the same, and therefore the primary pressure receiving area B1 and the effective back pressure receiving area B4 are the same. Thus, the piston 22 has the same effective back pressure area B4 as the primary pressure receiving area B1 of the primary pressure receiving surface 75 that receives the primary pressure P3 from the fluid in the primary pressure chamber 64 in one axial direction X1, and the back pressure chamber 55. The back pressure receiving surface 76 which receives the primary pressure P3 which goes to the other axial direction X2 from the inside fluid is provided.
[0072]
The piston 22 has a secondary pressure receiving surface 80 having a pressure receiving area B3-B2 that effectively receives the secondary pressure P4 from the fluid in the secondary pressure chamber 70 toward the other axial direction X2.
[0073]
In addition, the pressure receiving area B3 where the piston 22 receives the secondary pressure P4 in the other axial direction X2 from the fluid in the secondary pressure chamber 70 is an outward convexity that is the maximum outer diameter of the portion facing the secondary space 61 of the piston 22. The area obtained by subtracting the area (= B4) of the cross section perpendicular to the axis L1 of the axial direction other end 48 of the rod 24 from the circle having the outer diameter E3 of the portion 41 as a diameter, and is expressed by the following equation (8). The
[0074]
[Expression 7]

[0075]
The pressure receiving area B2 where the piston 22 receives the secondary pressure P4 in the axial direction X1 from the fluid in the secondary pressure chamber 70 is the maximum outer diameter of the portion facing the outer region 65 of the orifice 63 in the primary space of the piston 22. This is an area obtained by subtracting the primary pressure receiving area B1 from a circle having a diameter of E4, and is represented by the following equation (9).
[0076]
[Equation 8]

[0077]
FIG. 7 is a graph showing the secondary pressure P4 of the pressure reducing valve 20. FIG. 7 (1) shows the relationship between the primary pressure P3 and the secondary pressure P4, and FIG. The relationship with the secondary pressure P4 is shown. In the pressure reducing valve 20, the secondary pressure P4 is expressed by the following equation (10) from the balance of the forces acting on the piston 22.
[0078]
[Equation 9]

[0079]
Here, Ka is the spring constant of the spring member 23, and ΔHa is the amount of deflection from the natural state in the initial state of the spring member 23 shown in FIG. Za is a displacement amount of the piston 22 from the initial state shown in FIG. 6 to the other axial direction X2, and flows down the primary pressure P3 and the pressure reducing valve 20 as expressed by the equation (10). It is expressed as a function of the flow rate Q of the fluid.
[0080]
As described above, the above-described pressure reducing valve 20 is configured so that the back pressure chamber 55 is formed as described above, and the piston 22 receives the primary pressure P3 in the back pressure receiving area B4 in the other axial direction X2. It is possible to balance the force due to the primary pressure P3 that the piston 22 receives in the one axial direction X1 and the force due to the primary pressure P3 that the piston 22 receives in the other axial direction X2. That is, the primary pressure receiving area B1 and the back pressure receiving area B4 can be made the same, and the numerator of the second term on the right side in the above equation (10) can be made zero (B1-B4 = 0), even if the primary pressure P3 changes. The value of the second term on the right side in equation (10) can be set to a constant value (= 0) so that only the first term on the right side changes. Therefore, as shown in FIG. 7 (1), the amount of change ΔP4 of the secondary pressure P4 with respect to the amount of change ΔP3 of the primary pressure P3 is greatly reduced compared to the conventional configuration in which the back pressure receiving surface 76 is not formed on the piston 22. be able to.
[0081]
Further, in the pressure reducing valve 20, in order to increase the flow capacity, that is, the maximum allowable flow rate, the diameter E1 of the tip portion of the protruding piece 38 is increased to increase the back pressure receiving area B4 even if the primary pressure receiving area B1 is increased. Then, the change amount ΔP4 of the secondary pressure P4 with respect to the change amount ΔP3 of the primary pressure P3 can be suppressed to be small. Therefore, in order to increase the maximum allowable flow rate, it is not necessary to increase the pressure receiving area B3 that receives the secondary pressure P4 of the piston 22 in the other axial direction X2 as in the case where the back pressure receiving surface 76 is not formed on the piston 22. Therefore, it is not necessary to increase the outer diameter E3 of the outward convex portion 41, which is the maximum outer diameter of 22. Accordingly, the radial dimension of the pressure reducing valve 20 can be kept small. In this way, regardless of the flow rate Q, the radial dimension of the pressure reducing valve 20 can be kept small, and the change amount ΔP4 of the secondary pressure P4 with respect to the change amount ΔP3 of the primary pressure P3 can be kept small.
[0082]
Further, by providing the rod 24 and partially inserting it into the piston 22, the back pressure chamber 55 can be formed with a simple configuration, and the pressure reducing valve 20 that can obtain the above-described effect can be easily realized. Can do. Further, by using the piston inner space 56 between the piston 22 and the rod 24 as a passage through which fluid flows, a passage extending in the axial direction for communicating the region 64 of the space 60 and the space 61 to the piston 22 is formed. It is not necessary to install, the configuration is simple, and no complicated processing is required, and therefore it can be manufactured easily. In addition, since the strength of the piston 22 does not decrease due to the drilling of the passage, the thickness (radial dimension) of the piston 22 can be kept small, and this also reduces the radial dimension of the pressure reducing valve 20. Can do. Needless to say, a configuration in which a passage extending in the axial direction for communicating the region 64 of the space 60 and the space 61 is formed in the piston 22 is also included in the present invention.
[0083]
Further, in the present embodiment, the position of the cap member 27 on which the projection piece 38 is formed can be adjusted in the axial direction with respect to the housing body 25, so the axial distance between the projection piece 38 and the seat portion 62 of the piston 22 is adjusted. The pressure reduction ratio of the secondary pressure P4 to the primary pressure P3 can be adjusted.
[0084]
The above description of the pressure reducing valve 20 is merely an example, and the configuration can be changed. For example, the housing 21 and the rod 24 may be integrally formed.
[0085]
The valve device 200 shown in FIG. 4 is configured such that the other axial end portion 112 of the on-off valve 100 is inserted and connected to the cap member 27 of the pressure reducing valve 20. At this time, the axis L10 of the on-off valve 100 and the axis L1 of the pressure reducing valve 20 are coaxial, and the other end 112 in the axial direction of the on-off valve 100 and the cap member 27 of the pressure reducing valve 20 are provided with a sealing member. A seal is achieved. At this time, the discharge port 110 of the on-off valve 100 and the primary port 28 of the pressure reducing valve 20 are in communication, and the discharge pressure P2 and the primary pressure P3 are equal.
[0086]
In such a valve device 200, the fluid at the supply pressure P1 supplied from the supply port 108 of the on-off valve 100 is controlled to be discharged to the discharge port 110 by the on-off valve 100, and the primary pressure P3 discharged from the discharge port 110 is controlled. Is supplied to the primary port 28 of the pressure reducing valve 20, is reduced to the secondary pressure P 4 by the pressure reducing valve 20, and is discharged from the secondary port 30.
[0087]
Such a valve device 200 is provided, for example, in a high-pressure tank such as a tank containing oxygen carried by a firefighter at a fire site or the like, and used as a valve device for discharging the oxygen in the high-pressure tank to the outside while reducing the pressure. Can do. When used in such a high-pressure tank, the high-pressure tank needs to have a small radial dimension from the viewpoint of strength, and the valve device 200 that can keep the radial dimension small as described above is extremely suitable. It is.
[0088]
The description of the valve device 200 described above is merely an example, and the configuration can be changed. In addition, the use may be provided in a high-pressure tank other than the tank carried by the firefighter described above, and may be provided, for example, in a tank that contains a gas for constituting a fuel cell mounted on an electric vehicle or the like. Moreover, you may make it provide in fluid pressure apparatuses other than a tank. The fluid may be a gas or a liquid.
[0089]
【The invention's effect】
According to the first aspect of the present invention, in the on-off valve, the supply port and the discharge port are formed at both ends in the axial direction of the housing, and the passage in which fluid flows from the supply port to the discharge port is formed in the housing. Even if the supply pressure is increased, the opening and closing drive means controls the communication between the supply port and the discharge port and shuts off the axial driving force applied to the piston even if the supply pressure is increased. The maximum allowable flow rate can be increased without increasing it. Moreover, the radial dimension of the on-off valve can be reduced.
[0090]
According to the second aspect of the present invention, there is no need to separately provide a passage for connecting the supply port and the discharge port to the piston, the configuration is simple, and no complicated processing is required. It can be manufactured easily. Further, since there is no decrease in the strength of the piston due to the drilling of the passage, the thickness (radial dimension) of the piston can be kept small, and this can also reduce the radial dimension of the on-off valve.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a state where a piston 102 of an on-off valve 100 according to an embodiment of the present invention is disposed at a first position.
FIG. 2 is a cross-sectional view illustrating a state in which a piston 102 of the on-off valve 100 is disposed at a second position.
FIG. 3 is a cross-sectional view showing the on-off valve 100 in a simplified manner.
FIG. 4 is a cross-sectional view showing a valve device 200 in which an on-off valve 100 and a pressure reducing valve 20 are combined.
FIG. 5 is an enlarged sectional view showing a pressure reducing valve 20;
6 is a cross-sectional view showing a pressure reducing valve 20 in a simplified manner. FIG.
7 is a graph showing the secondary pressure P4 of the pressure reducing valve 20. FIG. 7 (1) shows the relationship between the primary pressure P3 and the secondary pressure P4, and FIG. The relationship with the secondary pressure P4 is shown.
FIG. 8 is a cross-sectional view showing a conventional on-off valve 1;
[Explanation of symbols]
100 On-off valve
101 housing
102 piston
103 Spring member
104 rod
108 Supply port
110 Discharge port
118 Valve seat
132 Solenoid
135 Back pressure chamber
144 First pressure chamber
150 Second pressure chamber
155 Supply pressure surface
156 Back pressure surface

Claims (2)

(A) a housing having a supply port formed at one end in the axial direction and a discharge port formed at the other end in the axial direction;
(B) a rod that is held on the housing by disposing one end in the axial direction on the one end side in the axial direction of the housing;
(C) a piston formed in a bottomed cylindrical shape,
(C1) The bottom portion is disposed on one end side in the axial direction of the housing, and the rod is inserted, and is held so as to be displaceable in the axial direction with respect to the housing and the rod,
(C2) The supply port and the discharge port are communicated and blocked by the displacement in the axial direction,
(C3) partitioning the housing into a first pressure chamber connected to the supply port and a second pressure chamber connected to the discharge port, and forming a back pressure chamber held at the supply pressure between the rod and the rod;
(C4) A supply pressure receiving surface of a supply pressure receiving area that receives a supply pressure directed in one axial direction from the fluid in the first pressure chamber; A back pressure receiving surface that is received by area is formed,
(D) open / close drive means for applying axial driving force to the piston to control communication and disconnection between the supply port and the discharge port;
(E) An on-off valve characterized in that a passage in which a fluid flows from the supply port to the discharge port is formed in the housing. The rod is a portion excluding one end in the axial direction and the outer peripheral portion of the portion inserted into the piston is provided with a radial interval between the inner peripheral portion of the piston, the piston and the rod An on-off valve according to claim 1, wherein an annular piston inner space is formed between the two, and the piston inner space forms part of a passage through which fluid flows from the supply port to the discharge port.

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