JP3965889B2

JP3965889B2 - Solenoid valve

Info

Publication number: JP3965889B2
Application number: JP2000272592A
Authority: JP
Inventors: 裕史葛山
Original assignee: Toyota Industries Corp
Current assignee: Toyota Industries Corp
Priority date: 2000-09-08
Filing date: 2000-09-08
Publication date: 2007-08-29
Anticipated expiration: 2020-09-08
Also published as: JP2002081567A

Description

【０００１】
【発明の属する技術分野】
本発明は、車両用ディーゼルエンジンなどの燃料噴射器を作動させるのに適したソレノイドバルブに関し、特に、軸方向の長さを短縮できるソレノイドバルブに関する。
【０００２】
【従来の技術】
車両用ディーゼルエンジンなどに用いられる燃料噴射器には、予め所定圧力で蓄圧しておいた燃料を噴射する蓄圧式の燃料噴射器と、噴射時に燃料を加圧して噴射する増圧式の燃料噴射器とが存在する。
【０００３】
増圧式の燃料噴射器は、作動流体（加圧燃料）の供給を受けて燃料を圧縮する増圧ピストンを有する増圧機構を備え、増圧された燃料の圧力に応じて作動するニードル弁を介してノズル噴孔から燃料を超高圧で噴射供給するものである。増圧機構の増圧ピストンを作動させるために、増圧ピストンの増圧室への作動流体（加圧燃料）の給排を切り換える３ポート２位置式のソレノイドバルブが燃料噴射器の頭部に一体に取り付けられる。
【０００４】
蓄圧式の燃料噴射器は、ニードル弁を含む可動部材の噴孔と反対側に制御圧力室を配設し、この制御圧力室に対する燃料圧力の供給又は遮断により、燃料噴射量及び燃料噴射タイミングを制御するものである。この制御圧力室に対する燃料の供給又は遮断のために、２ポート２位置式のソレノイドバルブが燃料噴射器の頭部に一体に取り付けられる。
【０００５】
いずれの方式の燃料噴射器も、ソレノイドバルブが燃料噴射器本体に一体に取り付けられる。これらのソレノイドバルブは、コイルを内蔵する固定鉄心に吸着される可動鉄心を有するソレノイド部と、前記可動鉄心に連結される弁部材を内蔵する磁性材料のバルブボディとを連結する構造となっている。ソレノイド部の特に固定鉄心とバルブボディとは軸方向に直列に接続され、コイルの通電によって固定鉄心に形成される磁束が磁性材料のバルブボディに漏れないようになっている。例えば、実開平７−２０４７８に記載されているソレノイドバルブは、コイルを内部に収納したステータ（固定鉄心）の周囲を非磁性リングで囲って同一端面を形成し、弁が形成される磁性材料のハウジング（バルブボディ）の端面を前記端面に突き合わせ状にして組み付けている。
【０００６】
【発明が解決しようとする課題】
以上説明した構造の従来のソレノイドバルブは、ステータ（固定鉄心）がハウジング（バルブボディ）の外部に突出した状態で組み付けられているため、ソレノイドバルブの軸方向の長さが長くなるという問題点を有していた。
【０００７】
例えば、ソレノイドバルブが燃料噴射器本体の頭部に連設され、エンジン等に搭載される場合には、搭載スペース等の制約から、軸方向寸法が規制されることがある。そこで、ソレノイドバルブ本体の長さを短縮する方法として、固定鉄心の長さを短くすることが考えられる。しかしながら、固定鉄心の長さを短くすると、コイルを励磁したときに生じる吸引力が必要な量だけ確保できなくなる。したがって、固定鉄心の長さを短くすることにも限界がある。
【０００８】
本発明は前記の問題点に鑑みてなされたものであって、その目的は、ソレノイドバルブの軸方向の長さを短縮でき、かつコイルを励磁したときに必要な吸引力が確保できるソレノイドバルブを提供することにある。
【０００９】
【課題を解決するための手段】
前記の目的を達成する第１の発明に係るソレノイドバルブは、コイルを内蔵する固定鉄心に吸引される可動鉄心を有するソレノイド部と、前記可動鉄心に連結される弁部材を内蔵する磁性材料のバルブボディとを連結したソレノイドバルブにおいて、前記バルブボディに形成された凹部に前記固定鉄心が嵌まり込む状態にして前記ソレノイド部を前記バルブボディに固設し、前記凹部の内周と前記固定鉄心の外周との間に非磁性材料のリング部材を介在させたことを特徴とするものである。
この第１の発明の構成によれば、固定鉄心をバルブボディの凹部に嵌め込み、弁と固定鉄心の距離を縮めることにより、ソレノイドバルブ本体の軸方向の長さを大幅に短縮するとともに、固定鉄心の必要な長さを確保する。また、非磁性材料のリング部材を固定鉄心の外周と前記凹部の内周との間に介在させることにより、固定鉄心のコイル周辺に発生した磁力線が磁性材料のバルブボディに漏洩して、可動鉄心に対する吸引力が減少することを防止する。
【００１０】
第２の発明に係るソレノイドバルブは、第１の発明において、前記可動鉄心が前記固定鉄心と向き合う平板状に形成され、前記凹部内に前記可動鉄心が収容されている。
この第２の発明の構成によれば、平板状の可動鉄心が固定鉄心と広い面積で向き合うので、固定鉄心の長さが短くても、必要な吸引力を発生させることができる。また、可動鉄心の軸方向の厚さを薄くすることと固定鉄心の軸方向長さを短くすることにより、ソレノイドバルブ本体の長さを更に短縮することができる。
【００１１】
第３の発明に係るソレノイドバルブは、第１または第２の発明において、前記リング部材の外周は前記凹部の内周に対してネジ込みで固定され、前記リング部材の内周には前記固定鉄心が嵌入され、前記固定鉄心の外周に嵌められたシール部材を介して前記リング部材の内周に対してシールされている。
この第３の発明の構成によれば、リング部材の内周が固定鉄心側のＯリングなどのシール部材のシール面を形成しているため、リング部材による確実なシールが出来るとともに、固定鉄心をバルブボディに固定する部材にシール機能を持たせる必要がなくなり、カバー等の固定部材を小型にできる。
【００１２】
第４の発明に係るソレノイドバルブは、第３の発明において、前記リング部材の先端は前記凹部の底面に対して面で当接することにより面シールを形成している。
この第４の発明の構成によれば、バルブボディの凹部にねじ込まれるリング部材の先端が前記凹部の底面との間で面シールを形成するため、リング部材の厚みを最小限にしてシール機能を達成することができる。
【００１３】
第５の発明に係るソレノイドバルブは、第２の発明において、前記リング部材の内周側であって前記可動鉄心の外周に位置する部分に非磁性材料のスペーサが配設され、前記リング部材の内周に嵌入される前記固定鉄心の前記凹部に対する位置が前記スペーサで決まり、前記固定鉄心は、前記バルブボディに固定されるカバーに押されて前記スペーサに当たるようになってる。
この第５の発明の構成によれば、平板状の可動鉄心に向き合う固定鉄心のバルブボディに対する位置がスペーサで決まり、バルブボディ側の弁部材に連結される可動鉄心と固定鉄心との間隔を微小で正確なものにすることができる。
【００１４】
第６の発明に係るソレノイドバルブは、第１〜第５の発明のいずれかの発明において、前記バルブボディは増圧式の燃料噴射器本体の頭部に連設され、前記弁部材の軸方向と前記燃料噴射器本体の軸方向とが直交する向きである。
この第６の発明の構成によれば、増圧式の燃料噴射器の頭部に連設されるソレノイドバルブは、増圧室への作動流体（加圧燃料）の給排を切り換えるために３ポート２位置になるとともに、ソレノイドバルブの弁部材の軸方向と燃料噴射器本体の軸方向とを直交させて全体がコンパクトに形成される。そのため、ソレノイドバルブの軸方向長さが短いものが有効となる。
【００１５】
【発明の実施の形態】
以下、本発明の実施の形態を図１に従って説明する。図１は、本発明の実施形態のソレノイドバルブの組立断面図であり、図２は、ソレノイドバルブのソレノイド部の側から見た側面図であり、図３は、ソレノイドバルブの各部品の軸方向展開図である。
【００１６】
図１において、ソレノイドバルブ１は、バルブボディ１１内に弁部材１２を収容し、バルブボディ１１に弁座部材１３をネジ込み、ソレノイド部１４をリング部材１５を介してバルブボディ１１内に一部挿入状態にして取り付けて構成される。
【００１７】
バルブボディ１１は磁性材料の切削加工品であり、その内部に、第１弁孔２１、第２弁孔２２、第１ねじ孔２３、凹部としての第２ねじ孔２４が、このソレノイド１４に向かって順次拡径して開放状態になるように設けられている。このバルブボディ１１には、第１弁孔２１に開口する供給ポート２５と、第２弁孔２２に開口する入出力ポート２６と、第２ねじ孔２４の底面４１に開口する排出ポート２７とが設けられている。第１弁孔２１の入口であって第２弁孔２２との境界には、第２弁座２８が形成されている。
【００１８】
図３に示されるように、弁部材１２は、第１弁孔２１内を軸方向に摺動するシリンダ３１と、第２弁座２８にソレノイド部１４から離れる方向で着座する第２弁部３２と、後述する弁座部材１３にソレノイド部１４に向かう方向で着座する第１弁部３３と、中心軸に沿った貫通孔３４と、貫通孔３４のソレノイド部１４に近い側に設けられた雌ねじ３５とを有する。第１弁部３３は、リング状の突起で形成されており、第２弁部３２は円錐面で形成されている。
【００１９】
図３において、第１ねじ孔２３の底面３６は、軸心に直角な面となった研磨面に形成されている。弁座部材１３は磁性材料の切削加工品であり、外周の雄ねじ３７と、軸直角面であって研磨された端面３８と、弁部材１２の端部が遊嵌される貫通孔３９と、ねじ込み工具を嵌める工具孔４０とを有する。端面３８の外側は第１ねじ孔２３の底面３６に対する当接面３８ａとなり、端面３８の内側は第１弁部３３に対する第１弁座３８ｂとなる。第１ねじ孔２３の底面３６及び弁座部材１３の当接面３８ａは研磨されているため、第１ねじ孔２３の雌ねじと雄ねじ３７が所定締めつけ力でねじ込まれた状態では、シール面を形成する。
【００２０】
図３において、ソレノイド部１４は、コイル５１を内蔵する短円筒状の固定鉄心５２と、この固定鉄心５２に吸引される円形平板状の可動鉄心５３と、固定鉄心５２の中心の陥没孔に収容される押しばね５４と、ボルト部材５５と、非磁性材料のカバー５６とを備えて構成される。ボルト部材５５の雄ねじ５５ａは弁部材１２の雌ねじ３５にねじ込まれ、ボルト部材５５の頭部５５ｂが可動鉄心５３に係合し、弁部材１２と可動鉄心５３は一体的に固定される。図１に明瞭に示されるように、ボルト部材５５の貫通孔５５ｃと、可動鉄心５３の周囲の貫通孔５３ａとにより、弁部材１２のシリンダ３１の内部室と排出ポート２７が連通し、弁部材１２の軸方向の摺動がシリンダ３１の内部室の作動流体の圧縮で阻害されないようになっている。
【００２１】
図１において、ソレノイド部１４による吸引方向と逆向きに付勢する押しばね５４は固定鉄心５２とボルト部材５５の間に配設され、コイル５１の非通電時には、第１弁部３３が第１弁座３８ｂから離座し、第２弁部３２が第２弁座２８に着座する。このようにして、図５に示すように、第２弁座２８と第２弁部３２が第２の弁Ａを形成し、第１弁部３３と弁座部材１３の後述する第１弁座３８ｂが第１の弁Ｂを形成する。
【００２２】
図１に示されるように、ソレノイド部１４の固定鉄心５２の先端側はバルブボディ１１の第２ねじ孔２４内に進入している。そのため、固定鉄心５２の磁力線が磁性材料のバルブボディ１１に流れる程度を少なくするため、バルブボディ１１の第２ねじ孔又は凹部２４の内周と固定鉄心５２の外周との間にステンレス材等の非磁性材料のリング部材１５を介在させる構造になっている。図３において、リング部材１５は、外周の雄ねじ１５ａと、内周面１５ｂと、先端面１５ｃとを有する。バルブボディ１１の第２ねじ孔２４の底面４１、及びリング部材１５の先端面１５ｃは、互いに研磨されている。第２ねじ孔２４にリング部材１５を所定締め付け力でねじ込むと、底面４１と先端面１５ｃの間に面シールが形成される。固定鉄心５２の外周溝にシール部材であるＯリング５７が嵌められており、このＯリング５７によってリング部材１５の内周面１５ｂと固定鉄心５２の外周との間がシールされる。この面シールとＯリング５７によって、排出ポート２７に至る空間が外部に対してシールされる。
【００２３】
図１に示されるように、固定鉄心５２は非磁性材料のスペーサ１６を介することにより第２ねじ孔２４の底面４１に対して位置決めされ、カバー５６でバルブボディ１１に向けて押し込まれている。図２に示すように、カバー５６は、ボルト５６ｂでバルブボディ１１の端面に対して取り付け可能な四角フランジ５６ａを有する。カバー５６をバルブボディ１１に取り付けることにより、固定鉄心５２のバルブボディ１１に対する位置が決まる。また、図１のスペーサ１６内に可動鉄心５３の円形平板の外周が嵌まる位置関係となっている。
【００２４】
リング部材１５とスペーサ１６の存在により、固定鉄心５２をバルブボディ１１内に嵌め込む構造であっても、コイル５１の通電による固定鉄心５２への可動鉄心５３の吸引が効率的に行われる。また、固定鉄心５２とバルブボディ１１との間のシールがリング部材１５を介して省スペースで行われる。さらに、スペーサ１６とカバー５６の締め付け構造により、バルブボディ１１に対する固定鉄心５２の位置も正確に決まる。
【００２５】
上記構造のソレノイドバルブ１の組み上げ手順を図３により説明する。バルブボディ１１の弁孔２１、２２内に弁部材１２を挿入する。つぎに、弁座部材１３の雄ねじ３７を第１ねじ孔２３にねじ込む。雄ねじ３７の第１ねじ孔２３への締め付け力は、弁部材１２の第１弁部３３が第１弁座３８ｂに着座する時の力に対抗できる軸力が発生し、第１ねじ孔２３の底面３６と弁座部材１３の当接面３８ａとの間の面シールを形成することができる力以上とする。つぎに、第２ねじ孔２４にリング部材１５の雄ねじ１５ａをねじ込む。雄ねじ１５ａの第２ねじ孔２４への締め付け力は、第２ねじ孔２４の底面４１とリング部材１５の先端面１５ｃの間の面シールを形成することができる力以上とする。
【００２６】
リング部材１５内にスペーサ１６を嵌め、弁部材１２と可動鉄心５３とを合わせ、ボルト部材５５の雄ねじ５５ａを弁部材１２の雌ねじ３５にねじ込む。ボルト部材５５により、弁部材１２と可動鉄心５３とが一体となる。つぎに、押しばね５４とＯリング５７を保持する固定鉄心５２をリング部材１５の内周面１５ｂに嵌める。最後に、カバー５６を固定鉄心５２に被せ、図２のボルト５６ｂにより、カバー５６をバルブボディ１１に引き込む。固定鉄心５２はスペーサ１６に向かって押し込まれて位置決めされる。
【００２７】
以上のソレノイドバルブ１の開閉作動を図１及び図４により説明する。図１はソレノイド部１４のコイル５１が非通電の状態を示し、図４はソレノイド部１４のコイル５１が通電の状態を示す。図１において、コイル５１が非通電のため、可動鉄心５３及び弁部材１２は、押しばね５４により、ソレノイド部１４から離れる方向に向かって押される。この状態では、第２弁座２８に第２弁部３２が着座し、第１弁座３８ｂから第１弁部３３が離座し、供給ポート２５と入出力ポート２６が遮断され、入出力ポート２６と排出ポート２７が連通する。
【００２８】
図４において、コイル５１に通電されると、固定鉄心５２に磁力線が形成され、可動鉄心５３及び弁部材１２がソレノイド部１４に向かう方向に吸引されて軸方向に移動する。この状態では、第２弁座２８が第２弁部３２から離座し、第１弁座３８ｂに第１弁部３３が着座し、入出力ポート２６と排出ポート２７が遮断され、供給ポート２５と入出力ポート２６が連通する。
【００２９】
以上説明した実施の形態のソレノイドバルブ１は以下の効果を有する。
（１）図１において、バルブボディ１１に形成された凹部２４に、コイル５１を内蔵する固定鉄心５２の略半分が嵌まり込むことにより、ソレノイドバルブ１の軸方向の長さを大幅に短縮することができる。
【００３０】
（２）通常、固定鉄心５２の一部をバルブボディ１１に嵌め込んだ場合、固定鉄心５２内のコイル５１に電流を流すことにより、コイル５１の周辺に発生した磁力線が磁性材料で構成されるバルブボディ１１へ漏洩してしまう。しかしながら、非磁性材料のリング部材１５を固定鉄心５２とバルブボディ１１の間に介在させることによって、漏洩する磁力線を低減することができる。これにより、コイル５１を励磁したときに生じる吸引力を必要な量だけ確保することができる。
【００３１】
（３）リング部材１５の内側には、外周にシール部材５７が嵌められた固定鉄心５２が嵌入しており、このシール部材５７により、リング材１５の内周部と固定鉄心５２の外周部におけるシール機能が省スペースで確実に確保される。
【００３２】
（４）リング部材１５はバルブボディ１１の凹部としての第２ねじ孔２４の内周に対してねじ込みにより固定されており、リング部材１５の先端は、バルブボディ１１に形成された第２ねじ孔２４の底面４１に対して面で当接しており、面シールが形成される。これにより、リング部材１５とバルブボディ１１の間のシール機能が省スペースで確実に確保される。
【００３３】
（５）固定鉄心５２が、スペーサ１６を介してバルブボディ１１とカバー５６とによって、挟まれる状態で固定されることにより、固定鉄心５２のバルブボディ１１に対する位置が決まり、固定鉄心５２と可動鉄心５３との相対的な位置関係が正確に決まり、両者の間の隙間を厳密にして、軸方向に短い固定鉄心５２の磁束を可動鉄心５３に効率的に導くことができる。
【００３４】
さらに、前述したソレノイドバルブ１が適用される燃料噴射器２の構造を図５により説明する。図５において、燃料噴射器２は、下端が段６１ａ付きで開放され、上端の内側に雌ネジ６１ｂが形成されたケーシング６１内に、第１ブロック６２、第２ブロック６３、第３ブロック６４および第４ブロック６５を下から順に挿入し、バルブボディ１１の入出力ポート２６の向きに突出する突出部６６の外周の雄ねじ６６ａを前記雌ねじ６１ｂにねじ込み、ソレノイドバルブ１の下方に、突出部６６及び第４ブロック６５内に形成された増圧機構３と、第１ブロック６２〜第３ブロック６４内に形成された噴射機構４を順に配設して形成される。この燃料噴射器２は図示のように噴射機構４を下にした下向き姿勢でディーゼルエンジンなどのエンジンに組み付けられる。
【００３５】
増圧機構３は、突出部６６内に、軸方向摺動自在なプランジャ７１を増圧ピストン７２に連結し、このプランジャ７１に戻しばね７３を作用させた状態で収容して構成される。第４ブロック６５内には、小径孔状の増圧室７４が形成され、この増圧室７４にプランジャ７１が摺動自在に嵌入されている。突出部６６内に大径孔状の加圧室７５が形成され、この加圧室７５に増圧ピストン７２が摺動自在に嵌入されている。この加圧室７５は、入出力ポート２６に連通している。
【００３６】
ケーシング６１の第４ブロック６５に対応する部分の側面に、燃料供給口７６が開口している。この燃料供給口７６から増圧室７４に至る通路７７には、燃料供給口７６から増圧室７４に向かう方向を順方向とする逆止弁７８が配設されている。戻しばね７３が収容される空間は、ドレン通路７９を経て排出ポート２７に連通している。
【００３７】
噴射機構４は、下端に噴射口８１を開口させた段６２ａ付の円柱形状の第１ブロック６２内と第２ブロック６３内とに、軸方向摺動自在なニードル８２と押しばね８３を収容し、第３ブロック６４で蓋をして構成される。第３ブロック６４の通路７７は、第２ブロック６３及び第１ブロック６２内の通路８４を経て高圧燃料の貯留部８５に連通している。
【００３８】
次に、上述した構成の燃料噴射器２の作動を図５により説明する。燃料の噴射開始前には、ソレノイドバルブ１のコイル５１は消磁状態であり、弁部材１２に接続された可動鉄心５３に押しバネ５４が作用することにより、バルブボディ１１との間の第２の弁Ａが閉じ、弁座部材１３との間の第１の弁Ｂが開き、入出力ポート２６を介して加圧室７５と排出ポート２７とが連通する。
【００３９】
加圧室７５と排出ポート２７が連通すると、増圧ピストン７２は戻しバネ７３のばね力により上方に付勢されるプランジャ７１を介して上方に移動し、逆止弁７８を経て燃料供給口７６から増圧室７４に低圧の燃料が充填される。増圧室７４に連通する貯留部８５も低圧となって、ニードル８２は押しばね８３のばね力により噴射口８１を遮断する非噴射位置となる。
【００４０】
燃料の噴射時には、噴射開始前の状態からソレノイドバルブ１のコイル５１を励磁する。コイル５１を励磁すると、弁部材１２に連結された可動鉄心５３が固定鉄心５２に吸引され、第１の弁Ｂが閉じ、第２の弁Ａが開き、入出力ポート２６を介して、加圧室２６と供給ポート２５とが連通する。
【００４１】
供給ポート２５から高圧の作動流体が加圧室７５内に流入するので、加圧室７５内の圧力は上昇する。加圧室７５内の圧力が上昇すると、増圧ピストン７２の外径とプランジャ７１の外径の比率で決まる増圧比で増圧室７４の燃料が加圧される。このとき、逆止弁７８は閉じた状態になっており、増圧室７４の高圧は、通路８４を経て貯留部８５内の燃料まで伝搬する。貯留部８５の高圧燃料が所定圧力に達すると、ニードル８２に上向きに作用する力が押しバネ８３の付勢力に打ち勝ち、ニードル８２が上方に移動して噴射口８１から高圧燃料が噴射される。
【００４２】
高圧燃料の噴射が終わると、コイル５１が非励磁となり、弁部材１２に連結された可動鉄心５３に押しバネ５４が作用することにより、第１弁Ｂが開き、第２の弁Ａが閉じることにより、入出力ポート２６を介して、加圧室７５と排出ポート２７とが連通して、加圧室７５に導入されていた作動流体が排出ポート２７から排出される。以上の繰り返しにより、高圧燃料が所定間隔毎に噴射される。
【００４３】
このような増圧式の燃料噴射器２にあっては、ソレノイドバルブ１が３ポート２位置式となって、入出力ポート２６が中心に位置する関係上、ソレノイドバルブ１の軸心は、燃料噴射器２の本体の軸心と直交する関係となる。このとき、３ポート２位置式のソレノイドバルブ１は２ポート２位置式のソレノイドバルブに比較して軸方向に長くなるが、軸方向長さを切り詰めたソレノイドバルブ１であるため、燃料噴射器２の頭部をコンパクトに形成することができる。そのため、エンジン搭載時の設置スペースの制限をクリアすることができる。
【００４４】
なお、実施の形態は前記に限定されるものではなく、例えば、次のように変更して実施してもよい。
（１）ソレノイド部１４における可動鉄心５３の形状は、平板状のものが好ましいが、その他の形状のものであってもよい。例えば固定鉄心５２の中心孔内に嵌まり込む棒状の可動鉄心であってもよい。さらに、この棒状の鉄心に平板状の鉄心を取り付けた可動鉄心であってもよい。
（２）バルブボディ１１及び弁座部材１３と弁部材１２との間で形成される弁は二つに限らず一つであってもよい。図５において、第２の弁Ａが省略され、第１の弁Ｂだけであって、供給ポート２５と入出力ポート２６が常時連通し、第１の弁Ｂが入出力ポート２６と排出ポート２７の間を連通又は遮断するだけのものであってもよい。この場合、第１の弁Ｂの弁座が弁座部材１３のソレノイド部１４側に形成され、コイル５１の通電によって、弁座から離座する形式の弁であってよい。
（３）リング部材１５にシール機能を持たせるものが好ましいが、リング部材１５を単なる介在部材とし、カバー５６にバルブボディ１１及び固定鉄心５２に対するシール機能を持たせるものであってもよい。この場合、カバー５６とバルブボディ１１の間に軸方向の嵌合部分を設け、この嵌合部分のいずれか一方にシール部材を配置すればよい。
（４）バルブボディ１１と固定鉄心５２の位置決めはスペーサ１６によるものが好ましいが、リング部材１５の内周の内径を大小にして段を設け、この段に固定鉄心５２を当てるものであってもよい。
【００４５】
（５）ソレノイドバルブを燃料噴射器と組み合わせる場合、増圧式の燃料噴射器に限らず、蓄圧式の燃料噴射器など他の方式の燃料噴射器と組み合わせてもよい。蓄圧式の燃料噴射器と組み合わせる場合、２ポート２位置式になるため、ソレノイドバルブの弁体の軸方向と燃料噴射器本体の軸方向とが一致する配列であってもよい。
（６）本発明のソレノイドバルブは、燃料噴射器に取り付けて使用するだけでなく、エンジン回りの燃料又は空気の給排に対して、軸方向の長さを短縮する必要性のある場合に、ソレノイドバルブ本体の単独又はその他の機器の組み合わせとして採用することができる。
【００４６】
【発明の効果】
以上詳述したように、第１の発明によれば、磁性材料のバルブボディに形成された凹部に非磁性材料のリング部材を介して固定鉄心を嵌め込むため、ソレノイドバルブ本体の軸方向の長さを大幅に短縮することができるとともに、コイル周辺に発生した磁力線がバルブボディに漏洩するのを低減することができる。すなわち、ソレノイドバルブ本体の軸方向の長さの短縮と、ソレノイド部の固定鉄心による可動鉄心の強力な吸引力の両方を並立させることができる。
【００４７】
第２の発明によれば、可動鉄心が固定鉄心と向き合う平板状に形成されているため、固定鉄心の長さが短くても、必要な吸引力を発生させることができ、ソレノイドバルブ本体の長さを更に短縮することができる。
【００４８】
第３または第４の発明によれば、凹部にねじ込まれるリング部材がバルブボディと固定鉄心の間のシール機能を有するため、確実なシール機能を達成できる。また、固定鉄心をバルブボディに固定するためのカバーにシール機能を持たせる必要がなくなり、カバーの構造を簡素化し、リング部材を付加したことによる外径方向への拡大を抑えることができる。
【００４９】
第５の発明によれば、スペーサにより固定鉄心のバルブボディに対する位置が正確に決まるため、可動鉄心と固定鉄心との間隔が厳密なものとなり、固定鉄心の可動鉄心に対する吸引力を有効に作用させることができる。
【００５０】
第６の発明によれば、増圧式燃料噴射器では、３ポート２位置式のソレノイドバルブを燃料噴射器の軸方向と直交するように頭部に連設することになるため、ソレノイドバルブの軸方向の長さが短くなり、エンジン搭載時の設置スペースの関係から極めて有効である。
【図面の簡単な説明】
【図１】本発明の実施形態のソレノイドバルブであって、コイルが非通電状態にあるときの組立断面である。
【図２】図１のソレノイドバルブのソレノイド部の側から見た側面図である。
【図３】図１のソレノイドバルブの各部品の軸方向展開図である。
【図４】本発明の実施形態のソレノイドバルブであって、コイルが通電状態にあるときの組立断面である。
【図５】図１のソレノイドバルブを頭部に有する燃料噴射器の組立断面図である。
【符号の説明】
１ソレノイドバルブ
２燃料噴射器
１１バルブボディ
１４ソレノイド部
１５リング部材
１６スペーサ
２４凹部
３６底面（シール面）
５１コイル
５２固定鉄心
５３可動鉄心
５６カバー
５７シール部材[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a solenoid valve suitable for operating a fuel injector such as a diesel engine for vehicles, and more particularly to a solenoid valve capable of shortening the axial length.
[0002]
[Prior art]
A fuel injector used in a diesel engine for a vehicle includes an accumulator fuel injector that injects fuel accumulated at a predetermined pressure in advance, and a booster fuel injector that pressurizes and injects fuel at the time of injection And exist.
[0003]
The pressure-intensifying fuel injector includes a pressure-increasing mechanism having a pressure-increasing piston that receives a supply of working fluid (pressurized fuel) and compresses the fuel, and includes a needle valve that operates according to the pressure of the boosted fuel. The fuel is injected and supplied from the nozzle hole through the ultrahigh pressure. In order to operate the pressure-increasing piston of the pressure-increasing mechanism, a 3-port 2-position solenoid valve that switches between supply and discharge of the working fluid (pressurized fuel) to the pressure-increasing chamber of the pressure-increasing piston is provided at the head of the fuel injector. Can be attached to one piece.
[0004]
The accumulator fuel injector has a control pressure chamber on the side opposite to the injection hole of the movable member including the needle valve, and the fuel injection amount and the fuel injection timing are controlled by supplying or shutting off the fuel pressure to the control pressure chamber. It is something to control. In order to supply or shut off the fuel to the control pressure chamber, a two-port two-position solenoid valve is integrally attached to the head of the fuel injector.
[0005]
In any type of fuel injector, the solenoid valve is integrally attached to the fuel injector body. These solenoid valves have a structure in which a solenoid part having a movable iron core attracted to a fixed iron core containing a coil and a magnetic material valve body containing a valve member connected to the movable iron core are connected. . In particular, the fixed iron core and the valve body of the solenoid part are connected in series in the axial direction so that the magnetic flux formed in the fixed iron core when the coil is energized does not leak to the valve body made of magnetic material. For example, a solenoid valve described in Japanese Utility Model Laid-Open No. 7-20478 is made of a magnetic material in which the same end surface is formed by surrounding a stator (fixed iron core) containing a coil with a non-magnetic ring to form a valve. The end surface of the housing (valve body) is assembled in abutment with the end surface.
[0006]
[Problems to be solved by the invention]
Since the conventional solenoid valve having the structure described above is assembled with the stator (fixed iron core) protruding outside the housing (valve body), the axial length of the solenoid valve becomes long. Had.
[0007]
For example, when the solenoid valve is connected to the head of the fuel injector body and is mounted on an engine or the like, the axial dimension may be restricted due to restrictions on the mounting space or the like. Therefore, as a method of shortening the length of the solenoid valve body, it is conceivable to shorten the length of the fixed iron core. However, if the length of the fixed iron core is shortened, a necessary amount of the attractive force generated when the coil is excited cannot be secured. Therefore, there is a limit to shortening the length of the fixed iron core.
[0008]
The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a solenoid valve that can shorten the axial length of the solenoid valve and can secure a necessary suction force when the coil is excited. It is to provide.
[0009]
[Means for Solving the Problems]
Achieve the above objectives According to the first invention The solenoid valve is a solenoid valve in which a solenoid part having a movable iron core attracted by a fixed iron core containing a coil and a valve body made of a magnetic material containing a valve member connected to the movable iron core are connected to each other. The solenoid part is fixed to the valve body in a state in which the fixed iron core is fitted in the concave part formed in the inner part, and a ring member made of a nonmagnetic material is provided between the inner periphery of the concave part and the outer periphery of the fixed iron core. It is characterized by being interposed.
this 1st invention According to the configuration, the axial length of the solenoid valve body is greatly reduced by fitting the fixed iron core into the recess of the valve body and reducing the distance between the valve and the fixed iron core, and the required length of the fixed iron core. Secure. Further, by interposing a ring member made of a nonmagnetic material between the outer periphery of the fixed iron core and the inner periphery of the concave portion, the magnetic lines generated around the coil of the fixed iron core leak to the valve body made of the magnetic material, and the movable iron core This prevents the suction force against the decrease.
[0010]
According to the second invention Solenoid valve First In this invention, the said movable iron core is formed in the flat form facing the said fixed iron core, and the said movable iron core is accommodated in the said recessed part.
this Second invention With this configuration, since the flat movable iron core faces the fixed iron core over a wide area, even if the length of the fixed iron core is short, a necessary suction force can be generated. Moreover, the length of the solenoid valve body can be further shortened by reducing the axial thickness of the movable iron core and shortening the axial length of the fixed iron core.
[0011]
According to the third invention Solenoid valve First or second In the invention, the outer periphery of the ring member is fixed to the inner periphery of the recess by screwing, and the fixed iron core is inserted into the inner periphery of the ring member, and the sealing member is fitted to the outer periphery of the fixed iron core. And is sealed against the inner periphery of the ring member.
this Of the third invention According to the configuration, since the inner periphery of the ring member forms a sealing surface of a sealing member such as an O-ring on the side of the fixed iron core, the ring member can be surely sealed, and the member for fixing the fixed iron core to the valve body It is not necessary to provide a sealing function to the cover, and the fixing member such as a cover can be made small.
[0012]
According to the fourth invention Solenoid valve Third In this invention, the front end of the ring member is in contact with the bottom surface of the recess by a surface to form a face seal.
this Of the fourth invention According to the configuration, since the tip of the ring member screwed into the concave portion of the valve body forms a surface seal with the bottom surface of the concave portion, the thickness of the ring member can be minimized and the sealing function can be achieved.
[0013]
According to the fifth invention Solenoid valve Second In the invention, a spacer made of a non-magnetic material is disposed on the inner peripheral side of the ring member and located on the outer periphery of the movable core, and the concave portion of the fixed core inserted into the inner periphery of the ring member The position is determined by the spacer, and the fixed iron core is pushed by a cover fixed to the valve body so as to hit the spacer.
this 5th invention With this configuration, the position of the fixed iron core facing the flat movable iron core with respect to the valve body is determined by the spacer, and the distance between the movable iron core connected to the valve member on the valve body side and the fixed iron core is made minute and accurate. can do.
[0014]
According to the sixth invention Solenoid valve Of the first to fifth inventions Either The In the present invention, the valve body is connected to the head of the pressure-intensifying fuel injector body, and the axial direction of the valve member and the axial direction of the fuel injector body are perpendicular to each other.
this Of the sixth invention According to the configuration, the solenoid valve connected to the head of the pressure-intensifying fuel injector is in the 3 port 2 position to switch the supply and discharge of the working fluid (pressurized fuel) to the pressure increasing chamber, The axial direction of the valve member of the solenoid valve and the axial direction of the fuel injector main body are orthogonal to each other so as to be compact. Therefore, a solenoid valve having a short axial length is effective.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIG. 1 is a sectional view of an assembly of a solenoid valve according to an embodiment of the present invention, FIG. 2 is a side view of the solenoid valve as viewed from the solenoid portion side, and FIG. 3 is an axial direction of each component of the solenoid valve. FIG.
[0016]
In FIG. 1, a solenoid valve 1 houses a valve member 12 in a valve body 11, a valve seat member 13 is screwed into the valve body 11, and a solenoid part 14 is partially inserted into the valve body 11 via a ring member 15. It is configured to be installed in the inserted state.
[0017]
The valve body 11 is a cut product of a magnetic material, and a first valve hole 21, a second valve hole 22, a first screw hole 23, and a second screw hole 24 as a recess face the solenoid 14. In this way, the diameter is gradually increased to open. The valve body 11 includes a supply port 25 that opens to the first valve hole 21, an input / output port 26 that opens to the second valve hole 22, and a discharge port 27 that opens to the bottom surface 41 of the second screw hole 24. Is provided. A second valve seat 28 is formed at the boundary between the inlet of the first valve hole 21 and the second valve hole 22.
[0018]
As shown in FIG. 3, the valve member 12 includes a cylinder 31 that slides in the axial direction in the first valve hole 21, and a second valve portion 32 that sits on the second valve seat 28 in a direction away from the solenoid portion 14. A first valve portion 33 seated in a direction toward the solenoid portion 14 on a valve seat member 13 to be described later, a through hole 34 along the central axis, and a female screw provided on the side of the through hole 34 close to the solenoid portion 14 35. The 1st valve part 33 is formed with the ring-shaped protrusion, and the 2nd valve part 32 is formed with the conical surface.
[0019]
In FIG. 3, the bottom surface 36 of the first screw hole 23 is formed on a polished surface that is a surface perpendicular to the axial center. The valve seat member 13 is a cut product of a magnetic material, and includes a male screw 37 on the outer periphery, a polished end surface 38 that is a surface perpendicular to the axis, a through hole 39 in which the end of the valve member 12 is loosely fitted, and screwing. And a tool hole 40 into which a tool is fitted. The outer side of the end surface 38 is a contact surface 38 a with respect to the bottom surface 36 of the first screw hole 23, and the inner side of the end surface 38 is a first valve seat 38 b with respect to the first valve portion 33. Since the bottom surface 36 of the first screw hole 23 and the contact surface 38a of the valve seat member 13 are polished, a sealing surface is formed when the female screw 37 and the male screw 37 of the first screw hole 23 are screwed in with a predetermined tightening force. To do.
[0020]
In FIG. 3, the solenoid portion 14 is housed in a short cylindrical fixed iron core 52 containing a coil 51, a circular flat plate-shaped movable iron core 53 attracted to the fixed iron core 52, and a recessed hole in the center of the fixed iron core 52. And a cover 56 made of a nonmagnetic material. The male screw 55a of the bolt member 55 is screwed into the female screw 35 of the valve member 12, the head portion 55b of the bolt member 55 is engaged with the movable iron core 53, and the valve member 12 and the movable iron core 53 are fixed integrally. As clearly shown in FIG. 1, the through-hole 55 c of the bolt member 55 and the through-hole 53 a around the movable iron core 53 allow the internal chamber of the cylinder 31 of the valve member 12 and the discharge port 27 to communicate with each other. Twelve axial slides are not hindered by the compression of the working fluid in the inner chamber of the cylinder 31.
[0021]
In FIG. 1, a push spring 54 that is biased in the direction opposite to the suction direction by the solenoid unit 14 is disposed between the fixed iron core 52 and the bolt member 55, and when the coil 51 is not energized, the first valve unit 33 is the first valve unit 33. The second valve portion 32 is seated on the second valve seat 28 after being separated from the valve seat 38b. Thus, as shown in FIG. 5, the second valve seat 28 and the second valve portion 32 form a second valve A, and the first valve seat, which will be described later, of the first valve portion 33 and the valve seat member 13. 38 b forms the first valve B.
[0022]
As shown in FIG. 1, the distal end side of the fixed iron core 52 of the solenoid portion 14 enters the second screw hole 24 of the valve body 11. Therefore, in order to reduce the extent to which the magnetic lines of force of the fixed iron core 52 flow into the valve body 11 of magnetic material, a stainless material or the like is provided between the second screw hole of the valve body 11 or the inner periphery of the recess 24 and the outer periphery of the fixed iron core 52. A non-magnetic material ring member 15 is interposed. In FIG. 3, the ring member 15 has an outer peripheral male screw 15a, an inner peripheral surface 15b, and a tip surface 15c. The bottom surface 41 of the second screw hole 24 of the valve body 11 and the front end surface 15c of the ring member 15 are ground together. When the ring member 15 is screwed into the second screw hole 24 with a predetermined tightening force, a face seal is formed between the bottom face 41 and the tip face 15c. An O-ring 57, which is a seal member, is fitted in the outer peripheral groove of the fixed iron core 52, and the space between the inner peripheral surface 15 b of the ring member 15 and the outer periphery of the fixed iron core 52 is sealed by the O-ring 57. By this face seal and the O-ring 57, the space reaching the discharge port 27 is sealed from the outside.
[0023]
As shown in FIG. 1, the fixed iron core 52 is positioned with respect to the bottom surface 41 of the second screw hole 24 through the spacer 16 made of a nonmagnetic material, and is pushed toward the valve body 11 by the cover 56. As shown in FIG. 2, the cover 56 has a square flange 56a that can be attached to the end surface of the valve body 11 with a bolt 56b. By attaching the cover 56 to the valve body 11, the position of the fixed iron core 52 with respect to the valve body 11 is determined. Moreover, it has the positional relationship in which the outer periphery of the circular flat plate of the movable iron core 53 fits in the spacer 16 of FIG.
[0024]
Due to the presence of the ring member 15 and the spacer 16, even when the fixed iron core 52 is fitted into the valve body 11, the movable iron core 53 is efficiently attracted to the fixed iron core 52 by energization of the coil 51. Further, the seal between the fixed iron core 52 and the valve body 11 is performed in a space-saving manner via the ring member 15. Furthermore, the position of the fixed iron core 52 with respect to the valve body 11 is accurately determined by the tightening structure of the spacer 16 and the cover 56.
[0025]
The assembly procedure of the solenoid valve 1 having the above structure will be described with reference to FIG. The valve member 12 is inserted into the valve holes 21 and 22 of the valve body 11. Next, the male screw 37 of the valve seat member 13 is screwed into the first screw hole 23. The tightening force of the male screw 37 to the first screw hole 23 generates an axial force that can counteract the force when the first valve portion 33 of the valve member 12 is seated on the first valve seat 38b. The force is greater than or equal to the force capable of forming a surface seal between the bottom surface 36 and the contact surface 38a of the valve seat member 13. Next, the male screw 15 a of the ring member 15 is screwed into the second screw hole 24. The tightening force of the male screw 15a to the second screw hole 24 is set to be equal to or greater than a force capable of forming a surface seal between the bottom surface 41 of the second screw hole 24 and the tip surface 15c of the ring member 15.
[0026]
The spacer 16 is fitted into the ring member 15, the valve member 12 and the movable iron core 53 are aligned, and the male screw 55 a of the bolt member 55 is screwed into the female screw 35 of the valve member 12. The valve member 12 and the movable iron core 53 are united by the bolt member 55. Next, the fixed iron core 52 that holds the pressing spring 54 and the O-ring 57 is fitted to the inner peripheral surface 15 b of the ring member 15. Finally, the cover 56 is put on the fixed iron core 52, and the cover 56 is pulled into the valve body 11 by the bolt 56b of FIG. The fixed iron core 52 is pushed toward the spacer 16 and positioned.
[0027]
The opening / closing operation of the solenoid valve 1 will be described with reference to FIGS. FIG. 1 shows a state where the coil 51 of the solenoid unit 14 is not energized, and FIG. 4 shows a state where the coil 51 of the solenoid unit 14 is energized. In FIG. 1, since the coil 51 is not energized, the movable iron core 53 and the valve member 12 are pushed toward the direction away from the solenoid part 14 by the push spring 54. In this state, the second valve portion 32 is seated on the second valve seat 28, the first valve portion 33 is separated from the first valve seat 38b, the supply port 25 and the input / output port 26 are shut off, and the input / output port 26 and the discharge port 27 communicate with each other.
[0028]
In FIG. 4, when the coil 51 is energized, magnetic lines of force are formed in the fixed iron core 52, and the movable iron core 53 and the valve member 12 are attracted in the direction toward the solenoid portion 14 and moved in the axial direction. In this state, the second valve seat 28 is separated from the second valve portion 32, the first valve portion 33 is seated on the first valve seat 38b, the input / output port 26 and the discharge port 27 are shut off, and the supply port 25 And the input / output port 26 communicate with each other.
[0029]
The solenoid valve 1 according to the embodiment described above has the following effects.
(1) In FIG. 1, the axial length of the solenoid valve 1 is greatly shortened by fitting substantially half of the fixed iron core 52 containing the coil 51 into the recess 24 formed in the valve body 11. be able to.
[0030]
(2) Normally, when a part of the fixed iron core 52 is fitted into the valve body 11, current lines are made to flow through the coil 51 in the fixed iron core 52, so that the lines of magnetic force generated around the coil 51 are made of a magnetic material. It will leak to the valve body 11. However, by interposing the ring member 15 made of a nonmagnetic material between the fixed iron core 52 and the valve body 11, it is possible to reduce the magnetic field lines that leak. As a result, a necessary amount of attractive force generated when the coil 51 is excited can be secured.
[0031]
(3) A fixed iron core 52 with a seal member 57 fitted on the outer periphery is fitted inside the ring member 15, and the seal member 57 allows the inner periphery of the ring material 15 and the outer periphery of the fixed iron core 52 to be inserted. The sealing function is ensured in a space-saving manner.
[0032]
(4) The ring member 15 is fixed by screwing into the inner periphery of the second screw hole 24 as a recess of the valve body 11, and the tip of the ring member 15 is a second screw hole formed in the valve body 11. The surface is in contact with the bottom surface 41 of 24 and a face seal is formed. Thereby, the sealing function between the ring member 15 and the valve body 11 is reliably ensured in a space-saving manner.
[0033]
(5) The fixed iron core 52 is fixed in a state of being sandwiched between the valve body 11 and the cover 56 via the spacer 16, whereby the position of the fixed iron core 52 with respect to the valve body 11 is determined, and the fixed iron core 52 and the movable iron core are determined. The relative positional relationship with 53 is accurately determined, the gap between the two is strict, and the magnetic flux of the fixed iron core 52 that is short in the axial direction can be efficiently guided to the movable iron core 53.
[0034]
Furthermore, the structure of the fuel injector 2 to which the solenoid valve 1 described above is applied will be described with reference to FIG. In FIG. 5, the fuel injector 2 has a first block 62, a second block 63, a third block 64, and a casing 61 in which a lower end is opened with a step 61a and a female screw 61b is formed inside the upper end. The fourth block 65 is inserted in order from the bottom, the male screw 66a on the outer periphery of the protruding portion 66 protruding in the direction of the input / output port 26 of the valve body 11 is screwed into the female screw 61b, and below the solenoid valve 1, the protruding portion 66 and The pressure increasing mechanism 3 formed in the fourth block 65 and the injection mechanism 4 formed in the first block 62 to the third block 64 are sequentially arranged. The fuel injector 2 is assembled to an engine such as a diesel engine in a downward posture with the injection mechanism 4 down as shown in the figure.
[0035]
The pressure-increasing mechanism 3 is configured such that an axially slidable plunger 71 is connected to a pressure-increasing piston 72 in a projecting portion 66 and a return spring 73 is acted on the plunger 71. In the fourth block 65, a small-diameter hole-shaped pressure increasing chamber 74 is formed, and a plunger 71 is slidably fitted in the pressure increasing chamber 74. A pressurizing chamber 75 having a large-diameter hole is formed in the protruding portion 66, and a pressure increasing piston 72 is slidably fitted into the pressurizing chamber 75. The pressurizing chamber 75 communicates with the input / output port 26.
[0036]
A fuel supply port 76 is opened on a side surface of a portion of the casing 61 corresponding to the fourth block 65. A check valve 78 having a forward direction from the fuel supply port 76 to the pressure increasing chamber 74 is disposed in the passage 77 from the fuel supply port 76 to the pressure increasing chamber 74. The space in which the return spring 73 is accommodated communicates with the discharge port 27 via the drain passage 79.
[0037]
The injection mechanism 4 accommodates an axially slidable needle 82 and a push spring 83 in a cylindrical first block 62 and a second block 63 having a step 62a with an injection port 81 opened at the lower end. The third block 64 is covered with a lid. The passage 77 of the third block 64 communicates with the high-pressure fuel reservoir 85 through the passage 84 in the second block 63 and the first block 62.
[0038]
Next, the operation of the fuel injector 2 configured as described above will be described with reference to FIG. Prior to the start of fuel injection, the coil 51 of the solenoid valve 1 is in a demagnetized state, and a push spring 54 acts on the movable iron core 53 connected to the valve member 12, so The valve A is closed, the first valve B between the valve seat member 13 is opened, and the pressurizing chamber 75 and the discharge port 27 communicate with each other via the input / output port 26.
[0039]
When the pressurizing chamber 75 and the discharge port 27 communicate with each other, the pressure-increasing piston 72 moves upward via the plunger 71 urged upward by the spring force of the return spring 73, and passes through the check valve 78 to the fuel supply port 76. The pressure increasing chamber 74 is filled with low pressure fuel. The reservoir 85 communicating with the pressure increasing chamber 74 is also low in pressure, and the needle 82 is in a non-injection position where the injection port 81 is blocked by the spring force of the push spring 83.
[0040]
At the time of fuel injection, the coil 51 of the solenoid valve 1 is excited from the state before the start of injection. When the coil 51 is excited, the movable iron core 53 connected to the valve member 12 is attracted to the fixed iron core 52, the first valve B is closed, the second valve A is opened, and the pressure is applied via the input / output port 26. The chamber 26 and the supply port 25 communicate with each other.
[0041]
Since the high-pressure working fluid flows from the supply port 25 into the pressurizing chamber 75, the pressure in the pressurizing chamber 75 increases. When the pressure in the pressurizing chamber 75 increases, the fuel in the pressure increasing chamber 74 is pressurized at a pressure increasing ratio determined by the ratio between the outer diameter of the pressure increasing piston 72 and the outer diameter of the plunger 71. At this time, the check valve 78 is in a closed state, and the high pressure in the pressure increasing chamber 74 is propagated to the fuel in the reservoir 85 through the passage 84. When the high-pressure fuel in the reservoir 85 reaches a predetermined pressure, the force acting upward on the needle 82 overcomes the urging force of the push spring 83, the needle 82 moves upward, and high-pressure fuel is injected from the injection port 81.
[0042]
When the injection of the high-pressure fuel is finished, the coil 51 is de-energized, and the first spring B is opened and the second valve A is closed by the pressing spring 54 acting on the movable iron core 53 connected to the valve member 12. Thus, the pressurizing chamber 75 and the discharge port 27 communicate with each other via the input / output port 26, and the working fluid introduced into the pressurizing chamber 75 is discharged from the discharge port 27. By repeating the above, high-pressure fuel is injected at predetermined intervals.
[0043]
In such a pressure-increasing fuel injector 2, the solenoid valve 1 is a three-port two-position type, and the input / output port 26 is located at the center, so that the shaft center of the solenoid valve 1 is the fuel injection. It becomes a relationship orthogonal to the axial center of the main body of the vessel 2. At this time, the three-port two-position solenoid valve 1 is longer in the axial direction than the two-port two-position solenoid valve, but the fuel injector 2 is a solenoid valve 1 whose axial length is truncated. The head can be made compact. Therefore, it is possible to clear the restriction on the installation space when the engine is mounted.
[0044]
In addition, embodiment is not limited to the above, For example, you may implement as changed as follows.
(1) The shape of the movable iron core 53 in the solenoid portion 14 is preferably a flat plate shape, but may be other shapes. For example, a rod-shaped movable iron core that fits into the center hole of the fixed iron core 52 may be used. Furthermore, the movable iron core which attached the flat iron core to this rod-shaped iron core may be sufficient.
(2) The number of valves formed between the valve body 11 and the valve seat member 13 and the valve member 12 is not limited to two and may be one. In FIG. 5, the second valve A is omitted, and only the first valve B is provided, the supply port 25 and the input / output port 26 are always in communication, and the first valve B is connected to the input / output port 26 and the discharge port 27. It may be one that only communicates or blocks between the two. In this case, the valve seat of the 1st valve B may be formed in the solenoid part 14 side of the valve seat member 13, and may be a valve of the type which leaves | separates from a valve seat by electricity supply of the coil 51.
(3) Although the ring member 15 is preferably provided with a sealing function, the ring member 15 may be a simple interposition member and the cover 56 may be provided with a sealing function for the valve body 11 and the fixed iron core 52. In this case, a fitting portion in the axial direction may be provided between the cover 56 and the valve body 11, and a seal member may be disposed on one of the fitting portions.
(4) The positioning of the valve body 11 and the fixed iron core 52 is preferably performed by the spacer 16. However, even if the inner diameter of the ring member 15 is made larger and smaller, a step is provided, and the fixed iron core 52 is applied to this step. Good.
[0045]
(5) When the solenoid valve is combined with the fuel injector, it is not limited to the pressure increasing type fuel injector, but may be combined with another type of fuel injector such as a pressure accumulating fuel injector. When combined with an accumulator fuel injector, the two-port, two-position system is used, so the axial direction of the valve body of the solenoid valve and the axial direction of the fuel injector body may be aligned.
(6) The solenoid valve of the present invention is not only used by being attached to a fuel injector, but also when it is necessary to reduce the axial length with respect to the supply or discharge of fuel or air around the engine. The solenoid valve main body can be used alone or in combination with other devices.
[0046]
【The invention's effect】
As detailed above, First According to this invention, since the fixed iron core is fitted into the concave portion formed in the magnetic material valve body via the nonmagnetic material ring member, the axial length of the solenoid valve body can be greatly reduced. At the same time, it is possible to reduce the leakage of magnetic lines of force generated around the coil to the valve body. That is, both the shortening of the axial length of the solenoid valve main body and the strong suction force of the movable iron core by the fixed iron core of the solenoid portion can be juxtaposed.
[0047]
Second According to the invention, since the movable iron core is formed in a flat plate shape facing the fixed iron core, the required suction force can be generated even if the length of the fixed iron core is short, and the length of the solenoid valve body is reduced. Further shortening is possible.
[0048]
3rd or 4th According to this invention, since the ring member screwed into the recess has a sealing function between the valve body and the fixed iron core, a reliable sealing function can be achieved. Further, it is not necessary to provide a sealing function to the cover for fixing the fixed iron core to the valve body, the structure of the cover can be simplified, and the expansion in the outer diameter direction due to the addition of the ring member can be suppressed.
[0049]
5th invention According to this, since the position of the fixed iron core relative to the valve body is accurately determined by the spacer, the distance between the movable iron core and the fixed iron core becomes strict, and the suction force of the fixed iron core to the movable iron core can be effectively applied.
[0050]
6th According to the present invention, in the pressure increasing type fuel injector, the three-port two-position solenoid valve is connected to the head so as to be orthogonal to the axial direction of the fuel injector. The length is shortened and it is extremely effective due to the installation space when the engine is installed.
[Brief description of the drawings]
FIG. 1 is a sectional view of a solenoid valve according to an embodiment of the present invention when a coil is in a non-energized state.
2 is a side view of the solenoid valve of FIG. 1 as viewed from the solenoid side.
FIG. 3 is an axial development view of each part of the solenoid valve of FIG. 1;
FIG. 4 is a sectional view of the solenoid valve according to the embodiment of the present invention when the coil is in an energized state.
5 is an assembled cross-sectional view of a fuel injector having the solenoid valve of FIG. 1 at its head.
[Explanation of symbols]
1 Solenoid valve
2 Fuel injector
11 Valve body
14 Solenoid part
15 Ring member
16 Spacer
24 recess
36 Bottom (seal surface)
51 coils
52 Fixed iron core
53 Movable iron core
56 Cover
57 Seal member

Claims

In a solenoid valve that connects a solenoid part having a movable iron core that is attracted to a fixed iron core containing a coil and a valve body made of a magnetic material containing a valve member that is connected to the movable iron core,
The solenoid part is fixed to the valve body in a state in which the fixed iron core is fitted in a recess formed in the valve body,
Interposing a ring member of a non-magnetic material between the inner periphery of the recess and the outer periphery of the fixed iron core ,
The outer periphery of the ring member is fixed to the inner periphery of the recess by screwing, the fixed iron core is inserted into the inner periphery of the ring member, and the seal member is inserted into the outer periphery of the fixed core through the seal member. A solenoid valve sealed against the inner periphery of the ring member.

The solenoid valve according to claim 1, wherein the movable iron core is formed in a flat plate shape facing the fixed iron core, and the movable iron core is accommodated in the recess.

3. The solenoid valve according to claim 1, wherein a tip of the ring member is in contact with a bottom surface of the recess by a surface to form a face seal.

In a solenoid valve that connects a solenoid part having a movable iron core that is attracted to a fixed iron core containing a coil and a valve body made of a magnetic material containing a valve member that is connected to the movable iron core,
  The solenoid part is fixed to the valve body in a state in which the fixed iron core is fitted in a recess formed in the valve body,
  Interposing a ring member of a non-magnetic material between the inner periphery of the recess and the outer periphery of the fixed iron core,
The movable iron core is formed in a flat plate shape facing the fixed iron core, the movable iron core is accommodated in the recess,
  A spacer made of a non-magnetic material is disposed on the inner peripheral side of the ring member and located on the outer periphery of the movable core, and the position of the fixed core inserted into the inner periphery of the ring member is relative to the recess. The solenoid valve is determined by a spacer, and the fixed iron core is pushed by a cover fixed to the valve body and hits the spacer.

In a solenoid valve that connects a solenoid part having a movable iron core that is attracted to a fixed iron core containing a coil and a valve body made of a magnetic material containing a valve member that is connected to the movable iron core,
  The solenoid part is fixed to the valve body in a state in which the fixed iron core is fitted in a recess formed in the valve body,
  Interposing a ring member of a non-magnetic material between the inner periphery of the recess and the outer periphery of the fixed iron core,
  The solenoid valve according to claim 1, wherein the valve body is connected to a head of a pressure-intensifying fuel injector body, and an axial direction of the valve member and an axial direction of the fuel injector body are orthogonal to each other.

In a solenoid valve that connects a solenoid part having a movable iron core that is attracted to a fixed iron core containing a coil and a valve body made of a magnetic material containing a valve member that is connected to the movable iron core,
  The solenoid part is fixed to the valve body in a state in which the fixed iron core is fitted in a recess formed in the valve body,
  Interposing a ring member of a non-magnetic material between the inner periphery of the recess and the outer periphery of the fixed iron core,
  The movable iron core is formed in a flat plate shape facing the fixed iron core, the movable iron core is accommodated in the recess,
  The valve body is connected to the head of the pressure-intensifying fuel injector body, and the axial direction of the valve member A solenoid valve characterized in that the axial direction of the fuel injector main body is orthogonal.

3. The solenoid according to claim 1, wherein the valve body is connected to a head portion of a pressure-intensifying fuel injector body, and an axial direction of the valve member and an axial direction of the fuel injector body are perpendicular to each other. valve.