JP4124811B2 - solenoid valve - Google Patents

Description

【００２８】
緩衝部材３１Ａは、最大衝突音が４９．０ｄＢ、最小衝突音が４３．０ｄＢであって、平均衝突音が４７．２ｄＢであった。緩衝部材３１Ｂは、最大衝突音が４６．０ｄＢ、最小衝突音が３９．０ｄＢであって、平均衝突音が４３．８ｄＢであった。緩衝部材３１Ｃは、最大衝突音が４６．０ｄＢ、最小衝突音が３９．０ｄＢであって、平均衝突音が４４．０ｄＢであった。よって、樹脂部材３２に２個のＯリング３３又はＯリング３３，３４を装着すれば、衝突音が樹脂部材３２にＯリング３３を１個だけ装着する場合より効果的に小さくなることが判明した。
【００２９】
表２は、吸着時の衝撃値の計測結果を示すものである。
【００３０】
【表２】

【００３１】
緩衝部材３１Ａは、最大衝撃値が１．６０、最小衝撃値が１．５０、平均衝撃値が１．５６である。緩衝部材３１Ｂは、最大衝撃値が１．４０、最小衝撃値が１．３０、平均衝撃値が１．３３である。緩衝部材３１Ｃは、最大衝撃値が１．４０、最小衝撃値が１．２０、平均衝撃値が１．３０である。よって、緩衝部材３１Ｂは、緩衝部材３１Ａに対して衝撃値を０．８５程度に抑えることができる。また、緩衝部材３１Ｃは、緩衝部材３１Ａに対して衝撃値を０．８３程度に抑えることができる。
【００３２】
従って、樹脂部材３２にＯリング３３を２個装着するか、或いは、Ｏリング３３，３４を装着すれば、衝突音と衝撃値を効果的に小さくすることができる。これは、２段階で衝撃を吸収するためと考えられる。すなわち、１個のＯリング３３では、例えば、可動鉄心２４Ａが固定鉄心２３に衝突する０．２〜０．３ｍｍ手前からＯリング３３が弾性変形して衝撃力を吸収するのみである。一方、２個のＯリング３３又はＯリング３３，３４では、例えば、可動鉄心２４Ａが固定鉄心２３に衝突する０．４〜０．６ｍｍ手前から弁体１７側のＯリング３３又はＯリング３４が弾性変形して衝撃力を吸収し、さらに０．２〜０．３ｍｍ手前から固定鉄心２３側のＯリング３３が弾性変形して衝撃力を吸収する。この場合、Ｏリング３３，３４は、相互に衝撃力を分散させるので、１個当たりの弾性変形量が小さい。
【００３３】
さらに、発明者らは、緩衝部材３１Ｂ，３１Ｃを用いて、固定鉄心２３が可動鉄心２４Ａを吸着した後のうなり音について実験を行った。表３は、吸着後のうなり音（ｄＢ）の計測結果を示すものである。
【００３４】
【表３】

【００３５】
緩衝部材３１Ｂは、最大うなり音が２５．０ｄＢ、最小うなり音が２３．０ｄＢであって、平均うなり音が２４．０ｄＢであった。緩衝部材３１Ｃは、最大うなり音が１７．０ｄＢ、最小うなり音が１７．０ｄＢであって、平均うなり音が１７．０ｄＢであった。よって、緩衝部材３１Ｃは、緩衝部材３１Ｂよりうなり音が小さくなることが判明した。
【００３６】
これは、シリコンゴムのＯリング３４は、弾性力がフッ素ゴムのＯリング３３より小さく、緩衝部材３１Ｃは、緩衝部材３１Ｂより反発力が小さくなるためと考えられる。つまり、緩衝部材３１Ｃは、可動鉄心２４Ａが整流回路２８特有の脈動によって振動しても、その振動に対する反発力を緩衝部材３１より発生しにくいため、可動鉄心２４Ａの振動を抑えられる。
【００３７】
従って、本実施の形態の電磁弁１Ａによれば、コイル２２への通電によって固定鉄心２３を励磁し、可動鉄心２４Ａを固定鉄心２３側に吸着することにより、弁機構に開閉動作させるものにおいて、可動鉄心２４Ａの吸着面に形成された保持孔２４ａに装着される樹脂部材３２と、弾性力を有するＯリング３３と、Ｏリング３３より弾性力の小さいＯリング３４とを可動鉄心２４ａの移動方向に重ね合わせて、樹脂部材３２と可動鉄心２４Ａとの間に配設しており、Ｏリング３３，３４の弾性変形量を小さくして劣化しにくくすることにより、衝突音の静音効果を持続するとともに、Ｏリング３３，３４の振動に対する反発力を小さくして、うなり音の発生を抑制するので、騒音を効果的に防止することができる。
【００３８】
特に、Ｏリング３３がフッ素ゴムを材質とし、Ｏリング３４がシリコンゴムを材質とすれば、騒音効果をより効果的に発揮することができる。
【００３９】
（第２実施の形態）
次に、本発明の電磁弁の第２実施の形態について図面を参照して説明する。図２は、電磁弁１Ｂの断面図である。
本実施の形態の電磁弁１Ｂは、第１実施の形態の電磁弁１Ａと使用用途及び基本的構造が同じであるが、ゴム板（「弾性部材」に相当するもの。）４２と樹脂板（「樹脂部材」に相当するもの。）４３Ａとからなる緩衝部材４１Ａ、及び、チューブ４４を備える点で、第１実施の形態の電磁弁１Ａと相違する。よって、ここでは、第１実施の形態の電磁弁１Ａとの相違点を中心に説明し、第１実施の形態の電磁弁１Ａと同様の構造には、同一符号を付して説明を省略する。
【００４０】
電磁弁１Ｂは、電磁弁１Ａと同様に、駆動部２０と弁部１０とを備える。駆動部２０の可動鉄心２４Ｂは、緩衝部材４１Ａが嵌め込まれる保持孔２４ａが吸着面に形成され、保持孔２４ａと同軸上に保持孔２４ａより小径の許容孔（「許容部」に相当するもの。）２４ｃが形成されている。緩衝部材４１Ａは、弾性材料を円柱形状に成形したゴム板４２と、樹脂を円柱形状に成形した樹脂板４３Ａとから構成される。ゴム板４２及び樹脂板４３Ａは、コイル２２が通電によって発熱した際にその熱を伝えられるため、耐熱性を有することが望ましい。本実施の形態では、ゴム板４２は、フッ素ゴムを材質とし、樹脂板４３Ａは、ポリフェニレンサルファイドを材質としている。ゴム板４２は、可動鉄心２４Ｂの許容孔２４ｃを覆うように保持孔２４ａに装填され、そのゴム板４２に重ね合わせて樹脂板４３Ａが保持孔２４ａに装填されている。樹脂板４３Ａは、可動鉄心２４Ｂが固定鉄心２３に接触することを防止するために、可動鉄心２４Ｂの吸着面から突出している。また、可動鉄心２４Ｂには、フッ素樹脂、ポリエチレンテレフタレートなどの樹脂からなるチューブ４４が外周に密着して被せられている。
【００４１】
このような電磁弁１Ｂは、コイル２２に通電して固定鉄心２３を励磁すると、可動鉄心２４Ｂがスプリング２６に抗して固定鉄心２３に衝突するまで上昇する。可動鉄心２４Ｂは、緩衝部材４１Ａの樹脂板４３Ａを介して固定鉄心２３に衝突し、固定鉄心２３との間にまだ隙間があるため、さらに上昇し続けようとする。その間、ゴム板４２は、樹脂板４３Ａと保持孔２４ａの内壁との間で押し潰されて弾性変形し、衝撃力を吸収するので、衝突音が小さくなる。これと同時に、ゴム板４２は、その一部を許容孔２４ｃに入り込ませて撓むので、樹脂板４３Ａと保持孔２４ａ内壁との間で押し潰される部分の弾性変形量が小さくなり、衝撃吸収時間が長くなる。
【００４２】
可動鉄心２４Ｂは、固定鉄心２３に吸着保持された後、整流回路２８が交流電流を整流する際に発生する脈動により振動するが、チューブ４４が可動鉄心２４Ｂとパイプ２５などの他の部材との接触を防止するため、うなり音が抑制される。
【００４３】
その後、コイル２２への通電を停止すると、可動鉄心２４Ｂがスプリング２６の付勢力で下降し、弁体１７を弁座１６に押し当てるため、制御流体がＩＮポート１２からＯＵＴポート１３へと供給されなくなる。可動鉄心２４Ｂの下降に伴って、樹脂板４３Ａがゴム板４２を加圧しなくなり、ゴム板４２が弾性力によって復元する。
【００４４】
ここで、許容孔２４ｃを可動鉄心２４Ｂに設けずに、ゴム板４２に換えてフッ素ゴム製のＯリングを使用した場合と、本実施の形態のように許容孔２４ｃを可動鉄心２４Ｂに設け、板状のゴム板４２を使用した場合とを比較すると、ゴム板４２は、Ｏリングより弾性変形量が小さく、静音効果が持続する。すなわち、Ｏリングは、樹脂板４３Ａと保持孔２４ａ内壁との間で押し潰されると、断面を大きく変形させて衝撃を吸収する。このとき、Ｏリングは、樹脂板４３Ａと保持孔２４ａ内壁に接触する部分が大きく弾性変形し、それを繰り返すため、劣化しやすい。よって、Ｏリングの耐久性が低く、静音効果の持続性に欠ける。それに対し、ゴム板４２は、樹脂板４３Ａと保持孔２４ａ内壁との間で押し潰されても、樹脂板４３Ａ及び保持孔２４ａ内壁との接触面が平らであるため、接触部分の弾性変形量がＯリングより小さい。しかも、ゴム板４２は、一部を許容孔２４ｃに入り込ませて逃がすことにより弾性変形を吸収されるため、劣化しにくい。よって、ゴム板４２の耐久性が高く、静音効果が持続する。こうした現象は、電磁弁１Ｂが蒸気などの高温流体を制御する場合により顕著になる。
【００４５】
従って、本実施の形態の電磁弁１Ｂによれば、コイル２２への通電によって固定鉄心２３を励磁し、可動鉄心２４Ｂを固定鉄心２３側に吸着することにより、弁機構に開閉動作させるものにおいて、可動鉄心２４Ｂの吸着面に形成した保持孔２４ａに弾性力を有するゴム板４２と、樹脂で形成された樹脂板４３Ａとを積層し、ゴム板４２の変形を許容する許容孔２４ｃを可動鉄心２４Ｂに設けており、ゴム板４２の劣化を抑制して、静音効果を持続させるとともに、衝撃時の衝撃吸収時間が長くなるので、騒音を効果的に防止することができる。
【００４６】
また、可動鉄心２４Ｂの摺動面に樹脂製のチューブ４４を装着しており、チューブ４４が、可動鉄心２４Ｂの摺動面と他の金属部材との衝突を防止するので、うなり音の発生を防止することができる。特に、チューブ４４をフッ素樹脂で形成すれば、蒸気などの高温の制御流体を制御することができる。
【００４７】
尚、許容孔２４ｃは、ゴム板４２の弾性変形を許容できるものであれば足り、許容孔２４ｃの形状を変形しても、また、樹脂板４３Ａ側に許容部を設けても、同様の作用効果が得られる。
【００４８】
具体的には、図３に示す電磁弁１Ｃのように、可動鉄心２４Ｃの保持孔２４ａの底部に環状溝２４ｄを形成し、樹脂板４３Ａが固定鉄心２３と可動鉄心２４Ｃとの間で挟み込まれたときに、ゴム板４２が可動鉄心２４の環状溝２４ｄに入り込むようにしてもよい。
【００４９】
また、図４に示す電磁弁１Ｄのように、可動鉄心２４Ｄに保持孔２４ａと連通する貫通孔２４ｅを形成し、樹脂板４３Ａが固定鉄心２３と可動鉄心２４Ｄとの間で挟み込まれたときに、ゴム板４２が可動鉄心２４Ｄの貫通孔２４ｅに入り込むようにしてもよい。
【００５０】
また、図５に示す電磁弁１Ｅのように、可動鉄心２４Ｅの吸着面に緩衝部材４１Ａより大径の孔２４ｆを形成して、ゴム板４２と樹脂板４３Ａとを遊嵌し、樹脂板４３Ａが固定鉄心２３と可動鉄心２４Ｅとの間で挟み込まれたときに、ゴム板４２が径方向に広がるように弾性変形し、さらに、孔２４ｆ内壁と樹脂板４３Ａの外周面との間に形成される隙間に入り込むようにしてもよい。
【００５１】
また、図６に示す電磁弁１Ｆのように、樹脂板４３Ｂのゴム板４２に接触する面に、可動鉄心２４Ｆと同軸上の許容孔４３ａを形成し、樹脂板４３Ｂが固定鉄心２３と可動鉄心２４Ｆとの間で挟み込まれたときに、ゴム板４２が樹脂板４３Ｂの許容孔４３ａに入り込むようにしてもよい。尚、許容孔４３ａは、必ずしも可動鉄心２４Ｆと同軸上に形成する必要はなく、樹脂板４３Ｂのゴム板４２に接触する面に形成していればよい。
【００５２】
また、図７に示す電磁弁１Ｇのように、樹脂板４３Ｃがゴム板４２と接触する面に環状の段差４３ｂを外周に沿って形成し、樹脂板４３Ｃが固定鉄心２３と可動鉄心２４Ｆとの間で挟み込まれたときに、ゴム板４２が樹脂板４３Ｃの段差４３ｂに入り込むようにしてもよい。
【００５３】
（第３実施の形態）
次に、本発明の電磁弁の第３実施の形態について図面を参照して説明する。図８は、電磁弁１Ｈの断面図である。
本実施の形態の電磁弁１Ｈは、第２実施の形態の電磁弁１Ｂと使用用途及び基本的構造が同じであるが、クッションゴム（「弾性部材」に相当するもの。）５２とリング（「樹脂部材」に相当するもの。）５３とからなる緩衝部材５１を備える点で、第２実施の形態の電磁弁１Ｂと相違する。よって、ここでは、第２実施の形態の電磁弁１Ｂとの相違点を中心に説明し、第２実施の形態の電磁弁１Ｂと同様の構造には、同一符号を付して説明を省略する。
【００５４】
電磁弁１Ｈは、電磁弁１Ｂと同様に、駆動部２０と弁部１０とを備える。駆動部２０の可動鉄心２４Ｈは、緩衝部材５１が嵌め込まれる保持孔２４ｈが吸着面に形成されるとともに、保持孔２４ｈと連通するように貫通孔（「許容部」に相当するもの。）２４ｉが軸方向に形成されている。緩衝部材５１は、フッ素ゴムなどの弾性材料を円柱形状に成形したクッションゴム５２と、ポリフェニレンサルファイドなどの樹脂を円筒形状に成形したリング５３とから構成される。リング５３は、可動鉄心２４Ｈに形成した保持孔２４ｈの内壁に沿って装着され、上端部が可動鉄心２４Ｈの吸着面から固定鉄心２３側に突出している。クッションゴム５２は、可動鉄心２４Ｈの貫通孔２４ｉ開口部を覆うようにリング５３に挿入され、上端部がリング５３よりさらに固定鉄心２３側に突出している。従って、クッションゴム５２は、リング５３を介して可動鉄心２４Ｈの保持孔２４ｈにがたつくことなく保持されている。
【００５５】
このような電磁弁１Ｈは、コイル２２に通電して固定鉄心２３を励磁すると、可動鉄心２４Ｈがスプリング２６に抗して固定鉄心２３に衝突するまで上昇する。可動鉄心２４Ｈは、緩衝部材５１のクッションゴム５２を介して固定鉄心２３に衝突し、クッションゴム５２の弾性変形により衝撃を吸収される。このとき、クッションゴム５２は、下端面が可動鉄心２４Ｈの貫通孔２４ｉに入り込んで変形するため、弾性変形量が小さくなり、衝撃吸収時間が長くなる。ここで、クッションゴム５２は、固定鉄心２３と可動鉄心２４Ｈの保持孔２４ｈ内壁との間で押し潰され、リング５３の内壁面を押圧して保持孔２４ｈの径方向に広がるように変形するため、可動鉄心２４Ｈの吸着面からの突出量が次第に減少するが、リング５３が固定鉄心２３に衝突して衝撃を吸収し、可動鉄心と固定鉄心との衝突を防止する。その後、可動鉄心２４Ｈは、チューブ４４によってうなり音を防止された状態で、固定鉄心２３に吸着保持される。これにより、弁体１７が弁座１６から所定量離間し、ＩＮポート１２から出力ポート１３に制御流体を供給する。
【００５６】
コイル２２への通電を停止すると、可動鉄心２４Ｈがスプリング２６の付勢力で下降し、弁体１７を弁座１６に押し当てるため、制御流体がＩＮポート１２からＯＵＴポート１３へと供給されなくなる。可動鉄心２４Ｂの下降に伴って、クッションゴム５２は、圧縮を解除され、弾性力によって復元する。
【００５７】
従って、本実施の形態の電磁弁１Ｈによれば、コイル２２への通電によって固定鉄心２３を励磁し、可動鉄心２４Ｈを固定鉄心１２側に吸着することにより、弁機構に開閉動作させるものにおいて、可動鉄心２４Ｈの吸着面に形成した保持孔２４ｈの内壁に沿って、可動鉄心２４Ｈの吸着面から固定鉄心２３側に突出するように取り付けられる環状のリング５３と、リング５３に挿通され、リング５３より可動鉄心２４Ｈの吸着面から固定鉄心２３側に突出するように取り付けられるクッションゴム５２と、を有し、クッションゴム５２の変形を許容する貫通孔２４ｉを少なくとも可動鉄心２４Ｈに設けており、クッションゴム５２の劣化を抑制して、静音効果を持続させるとともに、クッションゴム５２とリング５３とが時間差をもって衝撃を吸収することにより衝撃吸収時間を長くするので、騒音を効果的に防止することができる。
【００５８】
尚、貫通孔２４ｉは、クッションゴム５２の弾性変形を許容する「許容部」の役割を果たしており、クッションゴム５２の弾性変形を許容しうるものであれば、「許容部」の形状は貫通孔２４ｉに限定されず、また、リング５３の側面に孔を設けて「許容部」としても、同様の作用効果が得られる。
【００５９】
以上、本発明の実施の形態について説明したが、本発明は、上記実施の形態に限定されることなく、色々な応用が可能である。
例えば、上記第１実施の形態では、可動鉄心２４Ａに樹脂製のチューブを装着し、さらなる静音化を図っても良い。
【００６０】
【発明の効果】
本発明の電磁弁によれば、コイルへの通電によって固定鉄心を励磁し、可動鉄心を固定鉄心側に吸着することにより、弁機構に開閉動作させる電磁弁において、可動鉄心の吸着面に形成された孔に装着される樹脂部材と、弾性力を有する第１弾性部材と、第１弾性部材より弾性力の小さい第２弾性部材とを可動鉄心の移動方向に重ね合わせて、樹脂部材と可動鉄心との間に配設しているので、騒音を効果的に防止することができる。
【００６１】
また、本発明の電磁弁によれば、コイルへの通電によって固定鉄心を励磁し、可動鉄心を固定鉄心側に吸着することにより、弁機構に開閉動作させる電磁弁において、可動鉄心の吸着面に形成した孔に弾性力を有する弾性部材と、樹脂で形成された樹脂部材とを積層し、弾性部材の変形を許容する許容部を少なくとも可動鉄心又は樹脂部材の何れかに設けているので、騒音を効果的に防止することができる。
【００６２】
また、本実施の形態の電磁弁によれば、コイルへの通電によって固定鉄心を励磁し、可動鉄心を固定鉄心側に吸着することにより、弁機構に開閉動作させる電磁弁において、可動鉄心の吸着面に形成した孔の内壁に沿って、可動鉄心の吸着面から固定鉄心側に突出するように取り付けられる環状の樹脂部材と、樹脂部材に挿通され、樹脂部材より可動鉄心の吸着面から固定鉄心側に突出するように取り付けられる弾性部材と、を有し、弾性部材の変形を許容する許容部を少なくとも可動鉄心又は樹脂部材の何れかに設けているので、騒音を効果的に防止することができる。
【図面の簡単な説明】
【図１】本発明の第１実施の形態に係り、電磁弁の断面図である。
【図２】本発明の第２実施の形態に係り、電磁弁の断面図である。
【図３】同じく、電磁弁の変更例を示す図である。
【図４】同じく、電磁弁の変更例を示す図である。
【図５】同じく、電磁弁の変更例を示す図である。
【図６】同じく、電磁弁の変更例を示す図である。
【図７】同じく、電磁弁の変更例を示す図である。
【図８】本発明の第３実施の形態に係り、電磁弁の断面図である。
【図９】第１従来例の電磁弁の断面図である。
【図１０】第２従来例の電磁弁の吸着部を示す断面図である。
【図１１】第３従来例の電磁弁を示す断面図である。
【符号の説明】
１Ａ 電磁弁
１Ｂ 電磁弁
１Ｃ 電磁弁
１Ｄ 電磁弁
１Ｅ 電磁弁
１Ｆ 電磁弁
１Ｇ 電磁弁
１Ｈ 電磁弁
２２ コイル
２３ 固定鉄心
２４Ａ 可動鉄心
２４Ｂ 可動鉄心
２４Ｃ 可動鉄心
２４Ｄ 可動鉄心
２４Ｅ 可動鉄心
２４Ｆ 可動鉄心
２４Ｈ 可動鉄心
２４ａ 保持孔
２４ｂ 許容孔
２４ｄ 環状溝
２４ｅ 貫通孔
２４ｆ 孔
２４ｈ 保持孔
２４ｉ 貫通孔
３２ 樹脂部材
３３ Ｏリング
３４ Ｏリング
４２ ゴム板
４３Ａ 樹脂板
４３Ｂ 樹脂板
４３Ｃ 樹脂板
４３ａ 許容孔
４３ｂ 段差
５２ クッションゴム
５３ リング
５４ 貫通孔[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a solenoid valve used for fluid control and the like.
[0002]
[Prior art]
Solenoid valves used for fluid control and the like are used, for example, in medical devices for home treatment, oxygen generators, steam sterilizers used in hospitals, and the like. Such a solenoid valve excites the fixed iron core by energizing the conductive coil, and adsorbs the movable iron core to the fixed iron core side so that the valve body abuts or separates from the valve seat. Generates noise such as collision noise. In order to reduce this noise, various ideas have been made conventionally.
[0003]
In the electromagnetic valve 100 of the first conventional example shown in FIG. 9, a rubber plate 103 and a resin plate 104 are inserted between a fixed iron core 101 and a movable iron core 102, and the fixed iron core 101 and the rubber plate 103 are opposed to each other. The plate 104 and the movable iron core 102 are opposed to each other. Therefore, when the conductive coil 105 is energized and the fixed core 101 is excited, the movable core 102 rises until it collides with the fixed core 101, but the rubber plate 103 is elastically deformed to absorb the impact force of the movable core 102. The generation of collision noise is prevented (see, for example, Patent Document 1).
[0004]
The electromagnetic valve 200 of the second conventional example shown in FIG. 10 includes a movable core receiver 202 that receives the movable core 201 when a coil (not shown) is energized. The movable iron core receiver 202 is detachably mounted with a resin stopper member 203, and a rubber O-ring 204 is disposed between the movable iron core receiver 202 and the stopper member 203. When energizing a coil (not shown), the electromagnetic valve 200 moves until the movable iron core 201 collides with the stopper member 203. At this time, the O-ring 204 is elastically deformed to absorb the impact force of the movable iron core 201, thereby preventing the occurrence of collision noise (see, for example, Patent Document 2).
[0005]
In the electromagnetic valve 300 of the third conventional example shown in FIG. 11, a spring 303 is disposed between the fixed iron core 301 and the movable iron core 302, and an impact when the movable iron core 302 is attracted to the fixed iron core 301 is caused by the spring 303. Absorption prevents the generation of collision noise. The movable iron core 302 is covered with a resin tube 304. For this reason, even if the coil 305 using a rectifier circuit (not shown) is used and the rectifier circuit (not shown) pulsates and vibrates the movable iron core 302 when rectifying an alternating current, the movable iron core 302 does not directly contact other metal members. Therefore, the generation of a roaring sound is suppressed (for example, see Patent Document 3).
[0006]
[Patent Document 1]
Japanese Patent No. 2670476 (see paragraph 0013, FIG. 1)
[Patent Document 2]
Japanese Patent Laying-Open No. 2000-130631 (paragraphs 0020 and 0021, FIG. 1)
[Patent Document 3]
JP-A-6-74357 (paragraphs 0009 to 0011, FIG. 1).
[0007]
[Problems to be solved by the invention]
As described above, the electromagnetic valves 100, 200, and 300 of the first to third conventional examples are used for medical devices for home treatment, oxygen generators, steam sterilizers used in hospitals, etc. In order to reduce the cost of the device itself and to reduce the cost of the device itself, there has been a demand for further improving the noise performance of an electromagnetic valve that is one of the noise generation sources. However, the electromagnetic valves 100, 200, and 300 of the first to third conventional examples cannot sufficiently meet this requirement.
[0008]
That is, in the electromagnetic valve 100 of the first conventional example, the rubber plate 103 and the resin plate 104 are simply inserted between the fixed iron core 101 and the movable iron core 102, and therefore the coil 105 using a rectifier is used. In some cases, the movable iron core 102 adsorbed on the fixed iron core 101 vibrates and generates a beat sound.
Further, in the electromagnetic valve 200 of the second conventional example, every time the O-ring 204 receives the impact of the movable core 201, the surface that contacts the movable core receiver 202 and the surface that contacts the stopper member 203 are greatly elastically deformed. Therefore, it was easy to deteriorate. For this reason, the impact sound gradually increased and the silent effect was not sustained.
Furthermore, in the electromagnetic valve 300 of the third conventional example, there is a case where the movable iron core 301 is attracted to the fixed iron core 303 vigorously and generates a collision sound.
[0009]
Therefore, the present invention has been made to solve the above-described problems, and an object thereof is to provide an electromagnetic valve that can effectively prevent noise.
[0010]
[Means for Solving the Problems]
The solenoid valve according to the present invention has the following configuration.
(1) An electromagnetic valve that opens and closes a valve mechanism by exciting a fixed iron core by energizing a coil and attracting the movable iron core to the fixed iron core side is mounted in a hole formed in the adsorption surface of the movable iron core. A resin member, a first elastic member having an elastic force, and a second elastic member having a smaller elastic force than the first elastic member are overlapped in the moving direction of the movable iron core and disposed between the resin member and the movable iron core. It is characterized by doing.
[0011]
(2) In the invention described in (1), the first elastic member is made of fluoro rubber, and the second elastic member is made of silicon rubber.
[0012]
In the invention having the above-described configuration, for example, the first elastic member made of fluororubber and the second elastic member made of silicon rubber are attached to the resin member, and the resin member is attached to the hole formed on the adsorption surface of the movable iron core. . When the coil is energized, the movable iron core is attracted to the fixed iron core side to open and close the valve mechanism. At this time, the movable iron core moves until the resin member collides with the fixed iron core, but the first and second elastic members overlapped in the moving direction of the movable iron core are elastically deformed with a time difference to absorb the impact force of the movable iron core. To do. Therefore, the first and second elastic members have a small amount of elastic deformation and are not easily deteriorated, so that the silent effect of the collision sound can be maintained. Further, since the elastic force of the second elastic member is smaller than that of the first elastic member, even if the movable iron core vibrates in accordance with the alternating current vibration after being attracted to the fixed iron core, the first and second against the vibration. The repulsive force of the elastic member can be reduced to suppress the generation of beat sound. Therefore, according to the present invention, noise can be effectively prevented.
[0013]
(3) In a solenoid valve that opens and closes the valve mechanism by exciting the fixed iron core by energizing the coil and attracting the movable iron core to the fixed iron core side, the hole formed in the adsorption surface of the movable iron core has elastic force The elastic member and a resin member made of resin are laminated, and an allowable portion that allows deformation of the elastic member is provided in at least one of the movable iron core and the resin member.
[0014]
In the invention having the above-described configuration, when the coil is energized, the movable iron core is attracted to the fixed iron core side to open and close the valve mechanism. The movable iron core moves until the resin member collides with the fixed iron core, but at the same time as the resin member collides, the elastic member elastically deforms to absorb the impact force. At this time, since the elastic member is allowed to be deformed by the allowable portion, the elastic deformation amount of the portion to be crushed between the resin member and the movable iron core is reduced, and the impact absorption time is extended. As described above, according to the present invention, the deterioration of the elastic member can be suppressed, the silent effect can be maintained, and the impact absorption time at the time of impact can be prolonged, so that noise can be effectively prevented. Since the coil generates heat when energized, and the heat is transmitted to the elastic member and the resin member, it is desirable to select a member having heat resistance as the elastic member and the resin member.
[0015]
(4) In the invention described in (3), a resin tube is mounted on the sliding surface of the movable iron core.
According to the invention having the above configuration, since the tube prevents the sliding surface of the movable iron core from colliding with another metal member, it is possible to prevent the generation of a roaring sound.
[0016]
(5) In an electromagnetic valve that opens and closes the valve mechanism by exciting the fixed iron core by energizing the coil and attracting the movable iron core to the fixed iron core side, along the inner wall of the hole formed in the adsorption surface of the movable iron core An annular resin member attached so as to protrude from the adsorption surface of the movable iron core toward the fixed iron core, and an elastic member inserted through the resin member and attached so as to protrude from the adsorption surface of the movable iron core toward the fixed iron core And at least one of the movable iron core and the resin member is provided with an allowable portion that allows deformation of the elastic member.
[0017]
In the invention having the above-described configuration, when the coil is energized, the movable iron core is attracted to the fixed iron core side to open and close the valve mechanism. The movable iron core collides with the fixed iron core via the elastic member, and the shock is absorbed by elastically deforming the elastic member. At this time, since the elastic member is allowed to be deformed by the allowable portion, the elastic deformation amount is reduced and the impact absorption time is extended. Here, since the elastic member is compressed between the fixed iron core and the inner wall of the hole of the movable iron core and is deformed so as to press the resin member and expand in the radial direction of the hole, the protruding amount from the adsorption surface of the movable iron core However, the resin member collides with the fixed iron core and absorbs the impact, thereby preventing the collision between the movable iron core and the fixed iron core. Therefore, according to the present invention, the deterioration of the elastic member is suppressed and the silent effect is maintained, and the elastic member and the resin member absorb the shock with a time difference, thereby extending the shock absorption time. Can be prevented.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
Next, a first embodiment of a solenoid valve according to the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of the electromagnetic valve 1A.
The electromagnetic valve 1A is used for medical treatment devices for home treatment, oxygen generators, steam sterilizers used in hospitals, etc., and includes a drive unit 20 on the drive side and a valve unit 10 on the flow rate adjustment side. Prepare. In the drive unit 20, a conductive coil 22 is wound around a hollow cylindrical coil bobbin 21, a fixed iron core 23 is loaded in an upper end opening of the coil bobbin 21, and a movable iron core 24 </ b> A is coaxially connected to the fixed iron core 23. Is inserted from. A non-magnetic pipe 25 is inserted and fixed between the coil bobbin 21 and the fixed iron core 23 and the movable iron core 24A so as to protrude from the drive unit 20 to the valve unit 10, and the movable iron core 24A can be slid on the pipe 25. By being inserted, rigidity against sliding of the movable iron core 24A is secured. The movable iron core 24 </ b> A is always subjected to a downward force by a spring 26 contracted between the pipe 25.
[0019]
The fixed iron core 23 is fixed to the upper end portion of the coil bobbin 21, and a magnetic frame (magnetic frame) 27 is provided around the coil bobbin 21. The coil 22 is connected to the conducting wire 29 via the rectifying circuit 28, and a control device (not shown) is connected to the conducting wire 29 sent from the bush 30. The drive unit 20 is configured as a solenoid by injecting a filler made of resin into the bush 30 and the magnetic frame 27 after assembling these members.
[0020]
Such a drive unit 20 is coupled to the valve body 11 of the valve unit 10 via the coupling member 2. In the valve body 11, an IN port 12 and an OUT port 13 are formed, and a valve hole 14 for communicating the IN port 12 and the OUT port 13 is formed coaxially with the movable iron core 24A. The valve hole 14 communicates with a valve chamber 15 from which the lower end portion of the movable iron core 24A protrudes, and a valve seat 16 is provided at an opening communicating with the valve chamber 15. The valve body 17 that contacts or separates from the valve seat 16 is held on the lower end surface of the movable iron core 24A.
[0021]
Therefore, when the coil 22 is energized, the fixed iron core 23 attracts and holds the movable iron core 24 </ b> A against the urging force of the spring 26. As a result, the valve body 17 is separated from the valve seat 16 at a valve opening degree corresponding to the applied current, and the control fluid is supplied from the IN port 12 to the OUT port 13 at a predetermined flow rate. When energization of the coil 22 is stopped, the movable iron core 24 </ b> A is urged by the spring 26 to descend, and the valve body 17 is brought into contact with the valve seat 16. As a result, the control fluid is not supplied from the IN port 12 to the OUT port 13.
[0022]
Thus, the movable iron core 24 </ b> A is attracted and held after rising until it collides with the fixed iron core 23. Therefore, a collision sound is generated when the movable iron core 24A collides with the fixed iron core 23, or the movable iron core vibrates due to the pulsation generated when the rectifying circuit 28 rectifies the alternating current, and comes into contact with the pipe 25 or the like. May generate sound. In order to prevent such noise, a buffer member 31 is provided on the adsorption surface of the movable iron core 24A.
[0023]
The buffer member 31 includes a resin member 32, an O-ring (corresponding to a “first elastic member”) 33, and an O-ring (corresponding to a “second elastic member”) 34. The resin member 32 is formed by molding a resin such as plastic into a substantially T-shaped cross section, and O-rings 33 and 34 are mounted side by side in the axial direction from the distal end side of the leg portion. In the movable iron core 24A, a holding hole 24a for holding the large diameter portion of the resin member 32 and an insertion hole 24b having a smaller diameter than the holding hole 24a and holding the leg portion of the resin member 32 are formed coaxially from the suction surface. ing. The buffer member 31 inserts the leg portion of the resin member 32 from the holding hole 24a of the movable iron core 24A into the insertion hole 24b, and an O-ring between the large diameter portion of the resin member 32 and the inner wall of the holding hole 24a of the movable iron core 24A. 33 and 34 are accommodated. The large-diameter portion of the resin member 32 protrudes from the adsorption surface of the movable iron core 24A in order to prevent the fixed iron core 23 and the movable iron core 24A from colliding with each other.
[0024]
Here, various materials are conceivable for the O-rings 33 and 34. From the following experimental results, the O-ring 33 is made of fluoro rubber, and the O-ring 34 is made of silicon rubber.
[0025]
In the experiment, three types of the buffer member 31A, the buffer member 31B, and the buffer member 31C were used in the electromagnetic valve 1A, and the collision sound (dB) and the impact value at the time of operation when an alternating current was supplied to the coil 22 were measured. . Here, the buffer member 31 </ b> A has only one fluororubber O-ring 33 attached to the leg portion of the resin member 32. The buffer member 31 </ b> B has two fluororubber O-rings 33 attached to the legs of the resin member 32. The buffer member 31 </ b> C is configured by mounting an O-ring 33 made of fluoro rubber and an O-ring 34 made of silicon rubber on the leg portion of the resin member 32.
[0026]
Table 1 shows the measurement result of the collision sound (dB) during operation.
[0027]
[Table 1]

[0028]
The buffer member 31A had a maximum collision sound of 49.0 dB, a minimum collision sound of 43.0 dB, and an average collision sound of 47.2 dB. The buffer member 31B had a maximum collision sound of 46.0 dB, a minimum collision sound of 39.0 dB, and an average collision sound of 43.8 dB. The buffer member 31C had a maximum collision sound of 46.0 dB, a minimum collision sound of 39.0 dB, and an average collision sound of 44.0 dB. Therefore, it has been found that if two O-rings 33 or O-rings 33 and 34 are attached to the resin member 32, the collision sound is effectively reduced as compared with the case where only one O-ring 33 is attached to the resin member 32. .
[0029]
Table 2 shows the measurement results of the impact value during adsorption.
[0030]
[Table 2]

[0031]
The buffer member 31A has a maximum impact value of 1.60, a minimum impact value of 1.50, and an average impact value of 1.56. The buffer member 31B has a maximum impact value of 1.40, a minimum impact value of 1.30, and an average impact value of 1.33. The buffer member 31C has a maximum impact value of 1.40, a minimum impact value of 1.20, and an average impact value of 1.30. Therefore, the buffer member 31B can suppress the impact value to about 0.85 with respect to the buffer member 31A. Further, the buffer member 31C can suppress the impact value to about 0.83 with respect to the buffer member 31A.
[0032]
Therefore, if two O-rings 33 are attached to the resin member 32 or if the O-rings 33 and 34 are attached, the collision sound and the impact value can be effectively reduced. This is considered to absorb the impact in two stages. That is, in one O-ring 33, for example, the O-ring 33 is elastically deformed from 0.2 to 0.3 mm before the movable iron core 24A collides with the fixed iron core 23, and only absorbs the impact force. On the other hand, in the two O-rings 33 or the O-rings 33 and 34, for example, the O-ring 33 or the O-ring 34 on the valve element 17 side is 0.4 to 0.6 mm before the movable iron core 24A collides with the fixed iron core 23. The impact force is absorbed by elastic deformation, and the O-ring 33 on the fixed iron core 23 side is elastically deformed from 0.2 to 0.3 mm before and absorbs the impact force. In this case, since the O-rings 33 and 34 disperse the impact force to each other, the elastic deformation amount per one is small.
[0033]
Furthermore, the inventors conducted experiments on the beat sound after the fixed iron core 23 adsorbs the movable iron core 24A using the buffer members 31B and 31C. Table 3 shows the measurement result of the roaring sound (dB) after adsorption.
[0034]
[Table 3]

[0035]
The buffer member 31B had a maximum beat sound of 25.0 dB, a minimum beat sound of 23.0 dB, and an average beat sound of 24.0 dB. The buffer member 31C had a maximum beat sound of 17.0 dB, a minimum beat sound of 17.0 dB, and an average beat sound of 17.0 dB. Therefore, it was found that the buffer member 31C has a smaller beat sound than the buffer member 31B.
[0036]
This is probably because the silicon rubber O-ring 34 has a smaller elastic force than the fluororubber O-ring 33, and the buffer member 31C has a smaller repulsive force than the buffer member 31B. That is, even if the movable iron core 24A vibrates due to the pulsation peculiar to the rectifier circuit 28, the shock absorbing member 31C is less likely to generate a repulsive force against the vibration from the shock absorbing member 31, and thus the vibration of the movable iron core 24A can be suppressed.
[0037]
Therefore, according to the electromagnetic valve 1A of the present embodiment, the fixed iron core 23 is excited by energizing the coil 22, and the movable iron core 24A is attracted to the fixed iron core 23 side to open and close the valve mechanism. The moving direction of the movable iron core 24a includes the resin member 32 mounted in the holding hole 24a formed on the adsorption surface of the movable iron core 24A, the O-ring 33 having elasticity, and the O-ring 34 having smaller elasticity than the O-ring 33. And is disposed between the resin member 32 and the movable iron core 24A, and by reducing the amount of elastic deformation of the O-rings 33 and 34 so as not to deteriorate, the silent effect of the collision sound is maintained. At the same time, the repulsive force against the vibrations of the O-rings 33 and 34 is reduced to suppress the generation of beat noise, so that noise can be effectively prevented.
[0038]
In particular, if the O-ring 33 is made of fluoro rubber and the O-ring 34 is made of silicon rubber, the noise effect can be more effectively exhibited.
[0039]
(Second Embodiment)
Next, a second embodiment of the solenoid valve of the present invention will be described with reference to the drawings. FIG. 2 is a cross-sectional view of the electromagnetic valve 1B.
The electromagnetic valve 1B of the present embodiment is the same in use and basic structure as the electromagnetic valve 1A of the first embodiment, but has a rubber plate (corresponding to an “elastic member”) 42 and a resin plate ( It is different from the electromagnetic valve 1A of the first embodiment in that a buffer member 41A composed of 43A and a tube 44 are provided. Therefore, here, the difference from the electromagnetic valve 1A of the first embodiment will be mainly described, and the same structure as that of the electromagnetic valve 1A of the first embodiment will be denoted by the same reference numeral and description thereof will be omitted. .
[0040]
The electromagnetic valve 1B includes a drive unit 20 and a valve unit 10 in the same manner as the electromagnetic valve 1A. In the movable iron core 24B of the drive unit 20, a holding hole 24a into which the buffer member 41A is fitted is formed on the suction surface, and the holding hole 24a is coaxial with the holding hole 24a and corresponds to an allowable hole having a smaller diameter than the holding hole 24a. ) 24c is formed. The buffer member 41A is composed of a rubber plate 42 formed of an elastic material in a cylindrical shape and a resin plate 43A formed of a resin in a cylindrical shape. The rubber plate 42 and the resin plate 43 </ b> A are preferably heat resistant because they can transmit heat when the coil 22 generates heat by energization. In the present embodiment, the rubber plate 42 is made of fluoro rubber, and the resin plate 43A is made of polyphenylene sulfide. The rubber plate 42 is loaded in the holding hole 24a so as to cover the allowable hole 24c of the movable iron core 24B, and the resin plate 43A is loaded in the holding hole 24a so as to overlap the rubber plate 42. The resin plate 43A protrudes from the adsorption surface of the movable iron core 24B in order to prevent the movable iron core 24B from coming into contact with the fixed iron core 23. The movable iron core 24B is covered with a tube 44 made of a resin such as fluororesin or polyethylene terephthalate in close contact with the outer periphery.
[0041]
When such a solenoid valve 1 </ b> B energizes the coil 22 to excite the fixed iron core 23, the movable iron core 24 </ b> B moves up against the spring 26 against the fixed iron core 23. The movable iron core 24B collides with the fixed iron core 23 via the resin plate 43A of the buffer member 41A, and since there is still a gap between the movable iron core 24B and the fixed iron core 23, the movable iron core 24B continues to rise further. Meanwhile, the rubber plate 42 is crushed and elastically deformed between the resin plate 43A and the inner wall of the holding hole 24a and absorbs the impact force, so that the collision sound is reduced. At the same time, since the rubber plate 42 is bent by allowing a part of the rubber plate 42 to enter the permissible hole 24c, the amount of elastic deformation of the portion that is crushed between the resin plate 43A and the inner wall of the holding hole 24a is reduced, and shock absorption is achieved. The time will be longer.
[0042]
After the movable iron core 24B is adsorbed and held by the fixed iron core 23, the movable iron core 24B vibrates due to the pulsation generated when the rectifying circuit 28 rectifies the alternating current, but the tube 44 is connected to the movable iron core 24B and other members such as the pipe 25. To prevent contact, the roaring sound is suppressed.
[0043]
Thereafter, when energization of the coil 22 is stopped, the movable iron core 24B is lowered by the urging force of the spring 26 and presses the valve body 17 against the valve seat 16, so that the control fluid is supplied from the IN port 12 to the OUT port 13. Disappear. As the movable iron core 24B is lowered, the resin plate 43A does not pressurize the rubber plate 42, and the rubber plate 42 is restored by the elastic force.
[0044]
Here, without providing the permissible hole 24c in the movable iron core 24B, when using an O-ring made of fluoro rubber instead of the rubber plate 42, the permissible hole 24c is provided in the movable iron core 24B as in the present embodiment, Comparing with the case where the plate-like rubber plate 42 is used, the rubber plate 42 has a smaller elastic deformation amount than the O-ring, and the silent effect is sustained. That is, when the O-ring is crushed between the resin plate 43A and the inner wall of the holding hole 24a, the O-ring greatly deforms the cross section to absorb the impact. At this time, the portion of the O-ring that contacts the resin plate 43A and the inner wall of the holding hole 24a is greatly elastically deformed and repeats it, and thus the O-ring is easily deteriorated. Therefore, the durability of the O-ring is low and the durability of the silent effect is lacking. On the other hand, even if the rubber plate 42 is crushed between the resin plate 43A and the inner wall of the holding hole 24a, the contact surface between the resin plate 43A and the inner wall of the holding hole 24a is flat. Is smaller than the O-ring. In addition, the rubber plate 42 is less likely to deteriorate because elastic deformation is absorbed by allowing a part of the rubber plate 42 to enter the allowance hole 24c and let it escape. Therefore, the durability of the rubber plate 42 is high and the silent effect is sustained. Such a phenomenon becomes more prominent when the solenoid valve 1B controls a high-temperature fluid such as steam.
[0045]
Therefore, according to the electromagnetic valve 1B of the present embodiment, the valve mechanism is opened and closed by exciting the fixed iron core 23 by energizing the coil 22 and attracting the movable iron core 24B to the fixed iron core 23 side. A rubber plate 42 having elasticity and a resin plate 43A made of resin are laminated in a holding hole 24a formed on the adsorption surface of the movable iron core 24B, and an allowable hole 24c that allows deformation of the rubber plate 42 is formed in the movable iron core 24B. In this case, the deterioration of the rubber plate 42 is suppressed and the silent effect is maintained, and the impact absorption time at the time of impact is prolonged, so that noise can be effectively prevented.
[0046]
In addition, a resin tube 44 is mounted on the sliding surface of the movable iron core 24B, and the tube 44 prevents collision between the sliding surface of the movable iron core 24B and other metal members. Can be prevented. In particular, if the tube 44 is formed of a fluororesin, a high-temperature control fluid such as steam can be controlled.
[0047]
The permissible hole 24c is sufficient if it can permit elastic deformation of the rubber plate 42, and even if the shape of the permissible hole 24c is changed or a permissible portion is provided on the resin plate 43A side, the same effect is obtained. An effect is obtained.
[0048]
Specifically, like the solenoid valve 1C shown in FIG. 3, an annular groove 24d is formed at the bottom of the holding hole 24a of the movable iron core 24C, and the resin plate 43A is sandwiched between the fixed iron core 23 and the movable iron core 24C. The rubber plate 42 may enter the annular groove 24d of the movable iron core 24.
[0049]
Further, as in the solenoid valve 1D shown in FIG. 4, when the through hole 24e communicating with the holding hole 24a is formed in the movable iron core 24D, and the resin plate 43A is sandwiched between the fixed iron core 23 and the movable iron core 24D. The rubber plate 42 may enter the through hole 24e of the movable iron core 24D.
[0050]
Further, like the electromagnetic valve 1E shown in FIG. 5, a hole 24f having a diameter larger than that of the buffer member 41A is formed on the adsorption surface of the movable iron core 24E, and the rubber plate 42 and the resin plate 43A are loosely fitted to each other. Is sandwiched between the fixed iron core 23 and the movable iron core 24E, the rubber plate 42 is elastically deformed so as to expand in the radial direction, and is further formed between the inner wall of the hole 24f and the outer peripheral surface of the resin plate 43A. You may make it enter into the gap.
[0051]
Further, as in the electromagnetic valve 1F shown in FIG. 6, an allowable hole 43a coaxial with the movable iron core 24F is formed on the surface of the resin plate 43B that contacts the rubber plate 42, and the resin plate 43B is fixed to the fixed iron core 23 and the movable iron core. The rubber plate 42 may enter the permissible hole 43a of the resin plate 43B when sandwiched between 24F. The permissible hole 43a is not necessarily formed coaxially with the movable iron core 24F, and may be formed on the surface of the resin plate 43B that contacts the rubber plate 42.
[0052]
Further, like the electromagnetic valve 1G shown in FIG. 7, an annular step 43b is formed along the outer periphery on the surface where the resin plate 43C contacts the rubber plate 42, and the resin plate 43C is formed between the fixed iron core 23 and the movable iron core 24F. The rubber plate 42 may enter the step 43b of the resin plate 43C when sandwiched between them.
[0053]
(Third embodiment)
Next, a third embodiment of the electromagnetic valve of the present invention will be described with reference to the drawings. FIG. 8 is a cross-sectional view of the electromagnetic valve 1H.
The electromagnetic valve 1H of the present embodiment is the same in use and basic structure as the electromagnetic valve 1B of the second embodiment, but has a cushion rubber (corresponding to an “elastic member”) 52 and a ring (“ It is different from the electromagnetic valve 1B of the second embodiment in that a buffer member 51 comprising 53 is provided. Therefore, here, the difference from the electromagnetic valve 1B of the second embodiment will be mainly described, and the same structure as that of the electromagnetic valve 1B of the second embodiment will be denoted by the same reference numeral and the description thereof will be omitted. .
[0054]
The solenoid valve 1H includes a drive unit 20 and a valve unit 10 in the same manner as the solenoid valve 1B. The movable iron core 24H of the drive unit 20 has a holding hole 24h into which the buffer member 51 is fitted in the suction surface, and a through hole (corresponding to an “allowable part”) 24i so as to communicate with the holding hole 24h. It is formed in the axial direction. The buffer member 51 includes a cushion rubber 52 in which an elastic material such as fluoro rubber is molded into a cylindrical shape, and a ring 53 in which a resin such as polyphenylene sulfide is molded into a cylindrical shape. The ring 53 is mounted along the inner wall of the holding hole 24h formed in the movable iron core 24H, and the upper end portion projects from the adsorption surface of the movable iron core 24H to the fixed iron core 23 side. The cushion rubber 52 is inserted into the ring 53 so as to cover the opening of the through hole 24i of the movable iron core 24H, and the upper end protrudes further toward the fixed iron core 23 than the ring 53. Therefore, the cushion rubber 52 is held through the ring 53 without rattling in the holding hole 24h of the movable iron core 24H.
[0055]
When such an electromagnetic valve 1H energizes the coil 22 to excite the fixed iron core 23, the electromagnetic valve 1H moves up until the movable iron core 24H collides with the fixed iron core 23 against the spring 26. The movable iron core 24H collides with the fixed iron core 23 via the cushion rubber 52 of the buffer member 51, and the shock is absorbed by the elastic deformation of the cushion rubber 52. At this time, since the lower end surface of the cushion rubber 52 enters the through hole 24i of the movable iron core 24H and is deformed, the amount of elastic deformation is reduced and the impact absorption time is extended. Here, the cushion rubber 52 is crushed between the fixed iron core 23 and the inner wall of the holding hole 24h of the movable iron core 24H, and is deformed so as to press the inner wall surface of the ring 53 and expand in the radial direction of the holding hole 24h. The amount of protrusion of the movable iron core 24H from the adsorption surface gradually decreases, but the ring 53 collides with the fixed iron core 23 to absorb the shock, thereby preventing the collision between the movable iron core and the fixed iron core. Thereafter, the movable iron core 24 </ b> H is adsorbed and held on the fixed iron core 23 in a state where the beat sound is prevented by the tube 44. As a result, the valve body 17 is separated from the valve seat 16 by a predetermined amount, and the control fluid is supplied from the IN port 12 to the output port 13.
[0056]
When energization of the coil 22 is stopped, the movable iron core 24H is lowered by the urging force of the spring 26 and presses the valve element 17 against the valve seat 16, so that the control fluid is not supplied from the IN port 12 to the OUT port 13. As the movable iron core 24B descends, the cushion rubber 52 is released from compression and restored by elastic force.
[0057]
Therefore, according to the solenoid valve 1H of the present embodiment, the valve mechanism is opened and closed by exciting the fixed core 23 by energizing the coil 22 and attracting the movable core 24H to the fixed core 12 side. An annular ring 53 attached so as to protrude from the adsorption surface of the movable iron core 24H toward the fixed iron core 23 along the inner wall of the holding hole 24h formed on the adsorption surface of the movable iron core 24H, and the ring 53 is inserted. A cushion rubber 52 attached so as to protrude from the adsorbing surface of the movable iron core 24H to the fixed iron core 23 side, and a through hole 24i that allows deformation of the cushion rubber 52 is provided in at least the movable iron core 24H. While suppressing the deterioration of the rubber 52 and maintaining the silent effect, the cushion rubber 52 and the ring 53 are impacted with a time difference. Since a longer shock absorbing time by absorbing, it is possible to effectively prevent noise.
[0058]
The through hole 24i serves as an “allowable portion” that allows elastic deformation of the cushion rubber 52, and the shape of the “allowable portion” may be a through hole as long as the elastic deformation of the cushion rubber 52 can be allowed. It is not limited to 24i, and a similar effect can be obtained even if a hole is provided in the side surface of the ring 53 to form an “allowable portion”.
[0059]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various applications are possible.
For example, in the first embodiment, a resin tube may be attached to the movable iron core 24A to further reduce the noise.
[0060]
【The invention's effect】
According to the electromagnetic valve of the present invention, an electromagnetic valve that opens and closes the valve mechanism by exciting the fixed iron core by energizing the coil and attracting the movable iron core to the fixed iron core side is formed on the adsorption surface of the movable iron core. The resin member mounted in the hole, the first elastic member having an elastic force, and the second elastic member having a smaller elastic force than the first elastic member are overlapped in the moving direction of the movable core, so that the resin member and the movable iron core Therefore, noise can be effectively prevented.
[0061]
Further, according to the electromagnetic valve of the present invention, in the electromagnetic valve that opens and closes the valve mechanism by exciting the fixed iron core by energizing the coil and attracting the movable iron core to the fixed iron core side, Since an elastic member having elasticity in the formed hole and a resin member made of resin are laminated, and an allowable portion that allows deformation of the elastic member is provided at least in either the movable iron core or the resin member, noise Can be effectively prevented.
[0062]
In addition, according to the electromagnetic valve of the present embodiment, in the electromagnetic valve that opens and closes the valve mechanism by exciting the fixed iron core by energizing the coil and attracting the movable iron core to the fixed iron core side, the movable iron core is attracted. An annular resin member attached so as to protrude from the adsorption surface of the movable iron core toward the fixed iron core along the inner wall of the hole formed in the surface, and the fixed iron core is inserted into the resin member from the adsorption surface of the movable iron core. And an elastic member attached so as to protrude to the side, and at least one of the movable iron core and the resin member is provided with an allowable portion that allows deformation of the elastic member, so that noise can be effectively prevented. it can.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a solenoid valve according to a first embodiment of the present invention.
FIG. 2 is a sectional view of a solenoid valve according to a second embodiment of the present invention.
FIG. 3 is a view similarly showing a modification example of an electromagnetic valve.
FIG. 4 is a view similarly showing a modification example of a solenoid valve.
FIG. 5 is a diagram similarly showing a modification example of a solenoid valve.
FIG. 6 is a diagram similarly showing a modification example of the electromagnetic valve.
FIG. 7 is a view similarly showing a modified example of the electromagnetic valve.
FIG. 8 is a sectional view of a solenoid valve according to a third embodiment of the present invention.
FIG. 9 is a cross-sectional view of a solenoid valve of a first conventional example.
FIG. 10 is a cross-sectional view showing a suction portion of a solenoid valve of a second conventional example.
FIG. 11 is a cross-sectional view showing a solenoid valve of a third conventional example.
[Explanation of symbols]
1A Solenoid valve
1B Solenoid valve
1C Solenoid valve
1D solenoid valve
1E Solenoid valve
1F Solenoid valve
1G solenoid valve
1H Solenoid valve
22 coils
23 Fixed iron core
24A movable iron core
24B Movable iron core
24C movable iron core
24D movable iron core
24E Movable iron core
24F movable iron core
24H movable iron core
24a Holding hole
24b Allowable hole
24d annular groove
24e Through hole
24f hole
24h Holding hole
24i through hole
32 Resin members
33 O-ring
34 O-ring
42 Rubber plate
43A resin plate
43B resin plate
43C resin plate
43a Allowable hole
43b Step
52 Cushion rubber
53 rings
54 Through hole

Claims (2)

In the solenoid valve that opens and closes the valve mechanism by exciting the fixed iron core by energizing the coil and attracting the movable iron core to the fixed iron core side,
A large-diameter portion that is attached to a large-diameter hole that opens to the adsorption surface of the movable iron core and a small-diameter hole that opens to the bottom of the large-diameter hole, and a small-diameter portion that is retained by the large-diameter hole and a small-diameter portion that is retained by the small-diameter hole A resin member comprising:
A first O-ring having an elastic force;
A second O-ring having a smaller elastic force than the first O-ring,
The first O-ring and the second O-ring are overlapped with each other in the moving direction of the movable core, and are disposed between a lower portion of the large-diameter portion of the resin member and a bottom portion of the large-diameter hole of the movable core. solenoid valve. The solenoid valve according to claim 1,
The electromagnetic valve according to claim 1, wherein the first O-ring is made of fluoro rubber, and the second O-ring is made of silicon rubber.

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