JP4104271B2

JP4104271B2 - Mounting structure for screw fastening parts

Info

Publication number: JP4104271B2
Application number: JP2000116554A
Authority: JP
Inventors: 剛三梶; 和博浅山; 真也古澤; 宏史井上
Original assignee: Denso Corp; Toyota Motor Corp
Current assignee: Denso Corp; Toyota Motor Corp
Priority date: 2000-04-18
Filing date: 2000-04-18
Publication date: 2008-06-18
Anticipated expiration: 2020-04-18
Also published as: JP2001295734A

Description

【０００１】
【発明の属する技術分野】
この発明は、例えば高圧燃料ポンプのポンプハウジングに対して逆止弁を取り付ける構造のように、一方の部品の雌ネジ部に他方の部品の雄ネジ部を螺合させて、両部品を締結固定するようにしたネジ締結部品の取付構造に関するものである。
【０００２】
【従来の技術】
従来、この種の高圧燃料ポンプのポンプハウジングに対する逆止弁の取付構造としては、例えば特開平１１−１５３０６９号公報（第１従来構成）及び特開平１１−８２２３９号公報（第２従来構成）に開示されるような構成のものが知られている。
【０００３】
第１従来構成においては、ポンプハウジングの取付孔の内周面に雌ネジ部が形成されるとともに、逆止弁の外周面には雄ネジ部が形成されている。そして、この雌ネジ部に雄ネジ部を螺合させて、ポンプハウジングに逆止弁を締結することにより、ポンプハウジングの内部に設けられた燃料の流路と、逆止弁の内部に設けられた燃料の流路とが接続されるようになっている。また、ポンプハウジングの取付孔の内底面と逆止弁の先端部との間にはガスケットが介在され、このガスケットにより雌ネジ部と雄ネジ部とのネジ締結部がシールされるようになっている。
【０００４】
一方、第２従来構成においても、第１従来構成と同様に、ポンプハウジングの取付孔内周の雌ネジ部に逆止弁の外周の雄ネジ部を螺合させて、ポンプハウジングに逆止弁を締結することにより、ポンプハウジング内の燃料の流路と、逆止弁内の燃料の流路とが接続されるようになっている。また、この第２従来構成では、ポンプハウジングの取付孔の開口端周縁と逆止弁の雄ネジ部の基端外周との間にガスケットが介在され、このガスケットにより雌ネジ部と雄ネジ部とのネジ締結部がシールされるようになっている。
【０００５】
【発明が解決しようとする課題】
ところが、前記の従来構成においては、次のような問題点があった。
すなわち、第１及び第２従来構成では、ポンプハウジングの雌ネジ部に逆止弁の雄ネジ部を螺合させて、それらの部品をネジ締結する際に、そのネジ締結部で発生する切粉等の異物が、ポンプハウジング及び逆止弁内の燃料の流路に混入する。そのため、その後の高圧燃料ポンプの作動時に、前記異物がポンプ側又は燃料噴射弁側に運ばれて摺動部に挟まったり、流路を閉塞したりして作動不良や焼き付き等を招くおそれがあった。
【０００６】
このような不具合を防止するため、第１及び第２従来構成では、ポンプハウジングに対する逆止弁のネジ締結に先立って、雌ネジ部及び雄ネジ部に対してバリ取り作業を施すとともに、両部品のネジ締結後に、流路内への異物混入の有無を検査していた。このため、両ネジ部のバリ取り作業やネジ締結後の検査に多大な工数を必要として、生産性が悪くなるという問題があった。
【０００７】
また、第１従来構成では、ポンプハウジングの取付孔の内底面と逆止弁の先端部との間にガスケットが介在されて、雌ネジ部と雄ネジ部とのネジ締結部が内端部側でシールされている。このため、ポンプハウジングの雌ネジ部に逆止弁の雄ネジ部を螺合させて、それらの部品をネジ締結する際に、そのネジ締結力がガスケットを介して取付孔の内底面にかかり、その内側に配置されたシリンダ壁に歪みを発生させるという問題があった。
【０００８】
これに対して、第２従来構成では、ポンプハウジングの取付孔の開口端周縁と逆止弁の雄ネジ部の基端外周との間にガスケットが介在されて、雌ネジ部と雄ネジ部とのネジ締結部が外端部側にてシールされている。よって、ポンプハウジングの雌ネジ部に逆止弁の雄ネジ部を螺合させて、それらの部品をネジ締結する際には、逆止弁の先端部と取付孔の内底面との間に空間が形成されて、そのネジ締結力が取付孔の内底面に作用せず、シリンダ壁に歪みを発生させるおそれはなかった。
【０００９】
しかしながら、この第２従来構成では、逆止弁の先端部と取付孔の内底面との間に形成された空間が、ポンプハウジング内の加圧室を含む加圧空間に連通することになる。このため、加圧室のデッドボリュームが大きくなり、その分、高圧時の燃料体積収縮量が大きくなって吐出効率が低下するという問題があった。
【００１０】
この発明は、このような従来の技術に存在する問題点に着目してなされたものである。その目的は、第１部品の雌ネジ部に第２部品の雄ネジ部を螺合させて、両部品をネジ締結する際に、そのネジ締結部で発生する切粉等の異物が、両部品内の流体の流路に混入するのを防止することができるネジ締結部品の取付構造を提供することにある。
【００１１】
この発明のその他の目的は、高圧燃料ポンプにおいて、ポンプハウジングに逆止弁をネジ締結する際に、シリンダ壁に歪みが発生するのを防止することができ、さらには、加圧室のデッドボリュームを小さくすることができて、ポンプの吐出効率を向上させることができるネジ締結部品の取付構造を提供することにある。
【００１２】
【課題を解決するための手段】
以下、上記目的を達成するための手段及びその作用効果について記載する。
請求項１に記載の発明は、第１部品の取付孔の内周面に形成された雌ネジ部に対して、第２部品の外周面に形成された雄ネジ部を螺合させて、両部品を締結することにより、第１部品の内部に設けられた流体の第１流路と、第２部品の内部に設けられた流体の第２流路とを接続し、第１部品の取付孔の開口端周縁と第２部品の雄ネジ部の基端外周との間にシール手段を施してなるネジ締結部品の取付構造において、前記第２部品の先端部と第１部品の取付孔の内底面との間に、雌ネジ部及び雄ネジ部のネジ締結部と両流路との間を仕切るための仕切り部材が介在されてなり、前記仕切り部材は、第２部品の第２流路の内周面に沿って延びる筒状部と、第２部品の先端部に接触する第１接触部と、第１部品の取付孔の内底面に接触する第２接触部と、両接触部間を接続し、かつ流路の延長方向に沿って塑性変形可能な接続部とを備えてなることを特徴とするものである。
【００１３】
従って、請求項１に記載の発明によれば、第１部品の雌ネジ部に第２部品の雄ネジ部を螺合させて、両部品をネジ締結する際に、そのネジ締結部で発生する切粉等の異物が両部品内の流体の流路に混入するのを、仕切り部材にて確実に抑制することができる。よって、第１部品に対する第２部品のネジ締結に先立って、雌ネジ部及び雄ネジ部に対してバリ取り作業を施したり、両部品のネジ締結後に、流路内への異物混入の有無を検査したりする必要がなく、工数を削減して生産性の向上を図ることができる。
【００１５】
しかも、簡単な構造の仕切り部材により、ネジ締結部と両流路との間を確実に仕切ることができて、ネジ締結部で発生する切粉等の異物が両部品内の流体の流路に混入するのを有効に防止することができる。
【００１６】
請求項２に記載の発明は、請求項１に記載の発明において、前記第２接触部が、取付孔の内底面側に向かって凸状に形成されていることを特徴とするものである。
【００１７】
従って、請求項２に記載の発明によれば、凸状の第２接触部が取付孔の内底面に引っ掛かり等を生じることなく接触しながら塑性変形して、ネジ締結部と両流路との間を一層確実に仕切ることができる。
【００１８】
請求項３に記載の発明は、請求項１または請求項２に記載の発明において、前記第２部品が逆止弁機能を有することを特徴とするものである。
従って、請求項３に記載の発明によれば、逆止弁機能を有する第２部品をハウジング等の第１部品にネジ締結する取付構造において、ネジ締結部で発生する切粉等の異物が両部品内の流体の流路に混入するのを有効に防止することができる。
【００１９】
請求項４に記載の発明は、請求項１〜請求項３のいずれか一項に記載の発明において、前記第１部品が高圧燃料ポンプのポンプハウジングであり、前記第２部品がポンプハウジング内の加圧室から燃料噴射弁への高圧燃料通路の途中に設けられる逆止弁であることを特徴とするものである。
【００２０】
従って、請求項４に記載の発明によれば、高圧燃料ポンプにおいて、ポンプハウジングに逆止弁をネジ締結する際に、ネジ締結部で発生する切粉等の異物がポンプハウジング及び逆止弁内の燃料の流路に混入するのを、仕切り部材にて確実に抑制することができる。また、ポンプハウジングに逆止弁をネジ締結する際に、取付孔の内底面にネジ締結力がかからないため、シリンダ壁に歪みが発生するのを防止することができる。さらに、逆止弁の先端部と取付孔の内底面との間に形成された空間が、仕切り部材によってポンプハウジング内の加圧室を含む加圧空間から区画分離されるため、加圧室のデッドボリュームを小さくすることができ、ポンプの吐出効率を向上させることができる。
【００２１】
【発明の実施の形態】
（第１実施形態）
以下、この発明を高圧燃料ポンプのポンプハウジングに対する逆止弁の取付構造に具体化した第１実施形態を、図１〜図３に基づいて説明する。
【００２２】
図１に示すように、この高圧燃料ポンプ１１においては、ポンプハウジング１２内にシリンダ１３が配置され、その先端側の内部には加圧室１４が形成されている。シリンダ１３内にはプランジャ１５が同シリンダ１３の軸線方向へ往復摺動可能に嵌入支持されている。プランジャ１５は、図示しないカムシャフトの回転に伴い、そのカムシャフト上に設けられた図示しない駆動カムのカム面形状に応じて往復移動されるようになっている。
【００２３】
前記加圧室１４と連通するように、ポンプハウジング１２には燃料供給通路１６が形成されている。燃料供給通路１６には電磁スピル弁１７が配設され、図示しない電子制御装置の制御に基づいて開閉されるようになっている。そして、この電磁スピル弁１７が開弁された状態で、プランジャ１５が下降されるとき、流体としての低圧燃料が図示しない燃料タンクから図示しない燃料ポンプ及び燃料供給通路１６を介して加圧室１４内に吸入される。また、プランジャ１５が上昇されるとき、電磁スピル弁１７が閉弁されると、加圧室１４の容積が縮小変化されて、その内部の燃料が加圧されるようになっている。
【００２４】
前記加圧室１４と連通するように、シリンダ１３及びポンプハウジング１２には流体としての高圧燃料を圧送するのための第１流路１８が形成され、この第１流路１８には逆止弁１９が接続されている。そして、加圧室１４内から第１流路１８を介して圧送される高圧燃料の圧力により弁体２６を下流側に向かって押す力が、スプリング２７の弾性力と弁下流の燃料の圧力により、弁体２６を上流側に向かって押す力を上回った時、この逆止弁１９が開かれる。これにより、高圧燃料が第１流路１８から逆止弁１９内を通って図示しない燃料分配管に供給されて、エンジンのシリンダヘッドに取り付けられた各燃料噴射弁に分配されるようになっている。
【００２５】
次に、前記ポンプハウジング１２に対する逆止弁１９の取付構造について説明する。
図１及び図３に示すように、第１部品としてのポンプハウジング１２の側面にはボス部２１が突設されている。ボス部２１の中心には取付孔２２が形成され、その取付孔２２の内周面には雌ネジ部２３が形成されている。そして、取付孔２２の内底面２２ａの中心に前記第１流路１８の端部が開口されている。
【００２６】
前記ポンプハウジング１２の取付孔２２に取り付けられる第２部品としての逆止弁１９は、弁ケーシング２４と、その弁ケーシング２４内に嵌着されたシート体２５と、そのシート体２５に接離移動可能に対向配置された弁体２６と、その弁体２６をシート体２５に対する圧接位置に向かって付勢するスプリング２７とを備えている。そして、この逆止弁１９は、弁ケーシング２４内にスプリング２７、弁体２６及びシート体２５を順に挿入した状態で、弁ケーシング２４の端縁をかしめて、かしめ部２８を形成することにより、一体的に組み付けられている。
【００２７】
前記逆止弁１９の弁ケーシング２４の外周面には雄ネジ部２９が形成され、その雄ネジ部２９の基端部と対応するように、弁ケーシング２４の外周中央部には段差面２４ａが形成されている。そして、ポンプハウジング１２の雌ネジ部２３に逆止弁１９の雄ネジ部２９が螺合されることにより、ポンプハウジング１２の取付孔２２に逆止弁１９がネジ締結されている。この状態で、逆止弁１９のシート体２５の中心に設けられた高圧燃料のための第２流路３０が、ポンプハウジング１２の第１流路１８に接続されるようになっている。
【００２８】
前記逆止弁１９の雄ネジ部２９の基端外周にはシール手段としての円環状のガスケット３１が嵌挿され、ポンプハウジング１２の取付孔２２の開口端周縁と弁ケーシング２４上の段差面２４ａとの間に介在されている。そして、このガスケット３１により、雌ネジ部２３と雄ネジ部２９とのネジ締結部が、外端部側にてシールされるようになっている。
【００２９】
図１〜図３に示すように、前記逆止弁１９の先端部とポンプハウジング１２の取付孔２２の内底面２２ａとの間には、金属製の仕切り部材３２が介在されている。そして、この仕切り部材３２によって、雌ネジ部２３及び雄ネジ部２９のネジ締結部と、第１及び第２流路１８，３０との間が仕切られるようになっている。
【００３０】
前記仕切り部材３２は、逆止弁１９の第２流路３０の内周面に沿って延びる筒状部３３と、逆止弁１９の先端部に接触する第１接触部３４と、ポンプハウジング１２の取付孔２２の内底面２２ａに接触する第２接触部３５と、両接触部３４，３５間を接続する接続部３６とから構成されている。第１接触部３４は逆止弁１９の先端部に面接触するように平坦面状に形成され、第２接触部３５は取付孔２２の内底面２２ａ側に向かって円弧凸状に形成されている。
【００３１】
また、前記仕切り部材３２の接続部３６は、雌ネジ部２３と雄ネジ部２９とのネジ締結時に、流路１８，３０の延長方向に沿って塑性変形して、各接触部３４，３５を逆止弁１９の先端部及び取付孔２２の内底面２２ａに密着させるようになっている。さらに、仕切り部材３２の筒状部３３の外周面と逆止弁１９の第２流路３０の内周面との間の間隙Ｓ１は、雌ネジ部２３と雄ネジ部２９とのネジ締結部で発生する切粉等の異物のうちで、第１及び第２流路１８，３０に混入したときに支障を来す可能性のある異物の大きさよりも小さくなるように設定されている。
【００３２】
次に、前記のように構成されたポンプハウジング１２に対する逆止弁１９の取付構造について、その組み付け方法を図３に基づいて説明する。
さて、この組み付け時には、取付孔２２を上方に向けた状態でポンプハウジング１２を配置し、その取付孔２２の内底面２２ａ上に仕切り部材３２を挿入する。その後、逆止弁１９の雄ネジ部２９の基端外周にガスケット３１を嵌挿した状態で、その雄ネジ部２９をポンプハウジング１２の取付孔２２の雌ネジ部２３に螺合させる。
【００３３】
この場合、図３に鎖線で示すように、仕切り部材３２の第２接触部３５が取付孔２２の内底面２２ａに接触して、ポンプハウジング１２の第１流路１８が雌ネジ部２３と雄ネジ部２９とのネジ締結部から遮蔽されている。よって、この雌ネジ部２３に対する雄ネジ部２９の螺合時に、ネジ締結部で切粉等の異物が発生しても、その異物が下方の第１流路１８内に混入するおそれはない。
【００３４】
また、この雌ネジ部２３に対する雄ネジ部２９の螺合時には、仕切り部材３２の筒状部３３が逆止弁１９の第２流路３０内に徐々に進入して、逆止弁１９の第２流路３０が雌ネジ部２３と雄ネジ部２９とのネジ締結部から遮蔽されている。よって、ネジ締結部で発生した切粉等の異物が、上方の第２流路３０内に混入するおそれもない。
【００３５】
このように、雌ネジ部２３に対する雄ネジ部２９の螺合が終了すると、図１に示すように、ポンプハウジング１２の取付孔２２に逆止弁１９がネジ締結されて、ポンプハウジング１２の第１流路１８と逆止弁１９の第２流路３０とが接続される。この状態で、ガスケット３１が取付孔２２の開口端周縁と逆止弁１９上の段差面２４ａとの間に挟着されて、雌ネジ部２３と雄ネジ部２９とのネジ締結部が外端部側でシールされる。
【００３６】
また、このポンプハウジング１２に対する逆止弁１９のネジ締結状態では、仕切り部材３２の接続部３６が流路１８，３０の延長方向に沿って塑性変形して、第１接触部３４が逆止弁１９の先端部に密着されるとともに、第２接触部３５が取付孔２２の内底面２２ａに密着される。これによって、第１及び第２流路１８，３０が雌ネジ部２３と雄ネジ部２９とのネジ締結部から遮蔽される。このため、ネジ締結部で発生した切粉等の異物が逆止弁１９の先端部と取付孔２２の内底面２２ａとの間の空間Ｓ２に溜まっていても、その異物が高圧燃料ポンプ１１の作動時に、第１及び第２流路１８，３０に混入するおそれはない。
【００３７】
従って、この実施形態によれば、以下のような効果を得ることができる。
（１）このネジ締結部品の取付構造においては、ポンプハウジング１２の取付孔２２の内周面に雌ネジ部２３が形成されるとともに、逆止弁１９の外周面に雄ネジ部２９が形成されている。そして、この雄ネジ部２９に対して雌ネジ部２３を螺合させて、ポンプハウジング１２に逆止弁１９を締結することにより、ポンプハウジング１２の内部に設けられた燃料の第１流路１８が、逆止弁１９の内部に設けられた燃料の第２流路３０に接続されるようになっている。また、ポンプハウジング１２の取付孔２２の開口端周縁と逆止弁１９の雄ネジ部２９の基端外周との間にはガスケット３１が配設され、このガスケット３１により雌ネジ部２３と雄ネジ部２９とのネジ締結部がシールされている。さらに、逆止弁１９の先端部とポンプハウジング１２の取付孔２２の内底面２２ａとの間には、雌ネジ部２３及び雄ネジ部２９のネジ締結部と両流路１８，３０との間を仕切るための仕切り部材３２が介在されている。
【００３８】
このため、ポンプハウジング１２の雌ネジ部２３に逆止弁１９の雄ネジ部２９を螺合させて、両部品１２，１９をネジ締結する際に、そのネジ締結部で発生する切粉等の異物がポンプハウジング１２及び逆止弁１９内の燃料の流路に混入するのを、仕切り部材３２にて確実に抑制することができる。よって、ポンプハウジング１２に対する逆止弁１９のネジ締結に先立って、雌ネジ部２３及び雄ネジ部２９に対してバリ取り作業を施したり、両部品１２，１９のネジ締結後に、流路内への異物混入の有無を検査したりする必要がなく、工数を削減して生産性の向上を図ることができる。
【００３９】
また、ポンプハウジング１２に逆止弁１９をネジ締結する際に、逆止弁１９の先端部が取付孔２２の内底面２２ａに圧接されないため、その取付孔２２の内底面２２ａにネジ締結力がかかることがなく、シリンダ１３の内壁に歪みが発生するのを防止することができる。さらに、逆止弁１９の先端部と取付孔２２の内底面２２ａとの間に形成された空間Ｓ２が、仕切り部材３２によりポンプハウジング１２内の加圧室１４を含む加圧空間から区画分離されるため、加圧室１４のデッドボリュームを小さくすることができて、高圧燃料ポンプ１１の吐出効率を向上させることができる。
【００４０】
（２）このネジ締結部品の取付構造においては、前記仕切り部材３２が、逆止弁１９の第２流路３０の内周面に沿って延びる筒状部３３と、逆止弁１９の先端部に接触する第１接触部３４と、ポンプハウジング１２の取付孔２２の内底面２２ａに接触する第２接触部３５と、両接触部３４，３５間を接続し、かつ流路の延長方向に沿って塑性変形可能な接続部３６とから構成されている。このため、簡単な構造の仕切り部材３２により、ネジ締結部と両流路１８，３０との間を確実に仕切ることができて、ネジ締結部で発生する切粉等の異物が両部品１２，１９内の燃料の流路１８，３０に混入するのを有効に防止することができる。
【００４１】
（３）このネジ締結部品の取付構造においては、前記第２接触部３５が、取付孔２２の内底面２２ａ側に向かって円弧凸状に形成されている。このため、円弧凸状の第２接触部３５が取付孔２２の内底面２２ａに引っ掛かり等を生じることなく接触しながら塑性変形し、ネジ締結部と両流路１８，３０との間を一層確実に仕切ることができる。
【００４２】
（４）このネジ締結部品の取付構造においては、前記仕切り部材３２の筒状部３３の外周面と逆止弁１９内の第２流路３０の内周面との間の間隙Ｓ１が、燃料の流路１８，３０に混入して支障を来す可能性のある異物の大きさよりも小さくなるように設定されている。このため、ポンプハウジング１２の雌ネジ部２３に逆止弁１９の雄ネジ部２９をネジ締結する途中で、特定以上の大きさの異物が仕切り部材３２の筒状部３３の外周面と逆止弁１９内の第２流路３０の内周面との間の間隙Ｓ１を介して、逆止弁１９の第２流路３０内に侵入するのを確実に抑制することができる。
【００４３】
（第２実施形態）
次に、この発明の第２実施形態を図４に基づいて説明する。なお、この第２実施形態において、前記第１実施形態と同一又は近似する構成については、重複説明を避けるために、第１実施形態と同じ参照符号を付して、それらの詳細な説明は省略する。
【００４４】
さて、この実施形態においては、ポンプハウジング１２の取付孔２２の内底面２２ａの中央に、規制手段としてのほぼ円錐台形状の規制突部４０が形成されている。そして、ポンプハウジング１２の取付孔２２の内底面２２ａ上に仕切り部材３２を挿入したとき、仕切り部材３２の接続部３６が規制突部４０に係合されて、筒状部３３の軸線が逆止弁１９の第２流路３０の軸線とほぼ一致するように仕切り部材３２の位置が規制されるようになっている。これにより、ポンプハウジング１２の雌ネジ部２３に逆止弁１９の雄ネジ部２９をネジ締結する際に、仕切り部材３２が第２流路３０の延長方向と交差する方向に位置ずれするおそれが抑制される。
【００４５】
従って、この第２実施形態によれば、前記第１実施形態における（１）〜（４）に記載の効果に加えて、以下のような効果を得ることができる。
（５）このネジ締結部品の取付構造においては、前記ポンプハウジング１２の取付孔２２の内底面２２ａに規制突部４０が設けられ、この規制突部４０が仕切り部材３２と係合することにより、仕切り部材３２が逆止弁１９内の第２流路３０の延長方向と交差する方向に位置規制されるようになっている。このため、ポンプハウジング１２の取付孔２２に仕切り部材３２を挿入した状態で、ポンプハウジング１２の雌ネジ部２３に逆止弁１９の雄ネジ部２９をネジ締結する際に、仕切り部材３２が第２流路３０の延長方向と交差する方向に位置ずれするのを抑制することができる。よって、仕切り部材３２によりネジ締結部と両流路１８，３０との間を一層確実に仕切ることができて、ネジ締結部で発生する切粉等の異物がポンプハウジング１２及び逆止弁１９内の第２流路３０に混入するのを有効に防止することができる。
【００４６】
（変更例）
なお、この実施形態は上記の構成に限定されるものではなく、次のように変更してもよい。このように構成した場合でも、前記各実施形態と同様の作用及び効果を得ることができる。
【００４７】
・前記各実施形態では、逆止弁１９における弁ケーシング２４の端縁をシート体２５に対して、かしめ付けにより抜け止め固定しているが、これを溶接等の他の方法で抜け止め固定してもよい。
【００４８】
・前記各実施形態では、高圧燃料ポンプ１１のポンプハウジング１２に対する逆止弁１９の取付構成に具体化しているが、これを高圧燃料ポンプ１１とは異なった製品におけるネジ締結部品の取付構造に具体化してもよい。
【００４９】
さらに、上記各実施形態から把握できる他の技術的思想を、その効果とともに以下に記載する。
（ａ）前記取付孔の内底面と仕切り部材との間に、仕切り部材を第２部品内の流路の延長方向と交差する方向に位置規制するための規制手段を設けたことを特徴とする請求項１〜請求項５のいずれか一項に記載のネジ締結部品の取付構造。従って、この構成によれば、第１部品の取付孔に仕切り部材を挿入した状態で、第１部品の雌ネジ部に第２部品の雄ネジ部をネジ締結する際に、仕切り部材が流体の流路の延長方向と交差する方向に位置ずれするのを抑制することができる。よって、仕切り部材によりネジ締結部と両流路との間を一層確実に仕切ることができて、ネジ締結部で発生する切粉等の異物が両部品内の流体の流路に混入するのを有効に防止することができる。又、シート体２５の端部及び仕切り部材３２の筒状部３３の端部に面取り等を施さなくても、シート体２５の端部と、仕切り部材３２の筒状部３３の端部との干渉を防止することができる。
【００５０】
（ｂ）前記仕切り部材の筒状部の外周面と第２部品内の第２流路の内周面との間の間隙を、流体の流路に混入して支障を来す可能性のある異物の大きさよりも小さくなるように設定したことを特徴とする請求項２〜請求項５及び前記（ａ）のいずれか一項に記載のネジ締結部品の取付構造。従って、この構成によれば、第１部品の雌ネジ部に第２部品の雄ネジ部をネジ締結する途中で、特定以上の大きさの異物が仕切り部材の筒状部の外周面と第２部品内の第２流路の内周面との間の間隙を介して、第２部品の流路内に侵入するのを確実に抑制することができる。
【図面の簡単な説明】
【図１】この発明を具体化した高圧燃料ポンプのポンプハウジングに対する逆止弁の取付構造の第１実施形態を示す断面図。
【図２】図１の逆止弁の取付構造における仕切り部材を示す斜視図。
【図３】図１の逆止弁の取付構造を分解して示す部分断面図。
【図４】ポンプハウジングに対する逆止弁の取付構造の第２実施形態を示す断面図。
【符号の説明】
１１…高圧燃料ポンプ、１２…第１部品としてのポンプハウジング、１３…シリンダ、１４…加圧室、１５…プランジャ、１８…第１流路、１９…第２部品としての逆止弁、２２…取付孔、２２ａ…内底面、２３…雌ネジ部、２４…弁ケーシング、２５…シート体、２６…弁体、２７…スプリング、２９…雄ネジ部、３０…第２流路、３１…シール手段としてのガスケット、３２…仕切り部材、３３…筒状部、３４…第１接触部、３５…第２接触部、３６…接続部、４０…規制手段としての規制突部、Ｓ１…間隙。[0001]
BACKGROUND OF THE INVENTION
In the present invention, for example, like a structure in which a check valve is attached to a pump housing of a high-pressure fuel pump, a male screw part of the other part is screwed to a female screw part of one part, and both parts are fastened and fixed. The present invention relates to a mounting structure for screw fastening parts.
[0002]
[Prior art]
Conventionally, as a structure for attaching a check valve to the pump housing of this type of high-pressure fuel pump, for example, Japanese Patent Application Laid-Open No. 11-153069 (first conventional structure) and Japanese Patent Application Laid-Open No. 11-82239 (second conventional structure). A configuration as disclosed is known.
[0003]
In the first conventional configuration, a female screw portion is formed on the inner peripheral surface of the mounting hole of the pump housing, and a male screw portion is formed on the outer peripheral surface of the check valve. Then, by screwing the male screw part into the female screw part and fastening the check valve to the pump housing, the fuel flow path provided in the pump housing and the check valve are provided. The fuel flow path is connected. In addition, a gasket is interposed between the inner bottom surface of the mounting hole of the pump housing and the tip of the check valve, and the screw fastening portion between the female screw portion and the male screw portion is sealed by this gasket. Yes.
[0004]
On the other hand, in the second conventional configuration, similarly to the first conventional configuration, the male screw portion on the outer periphery of the check valve is screwed into the female screw portion on the inner periphery of the mounting hole of the pump housing, so that the check valve is connected to the pump housing. Is connected to the fuel flow path in the pump housing and the fuel flow path in the check valve. Further, in the second conventional configuration, a gasket is interposed between the peripheral edge of the opening end of the mounting hole of the pump housing and the outer periphery of the proximal end of the male threaded portion of the check valve. The screw fastening portion is sealed.
[0005]
[Problems to be solved by the invention]
However, the conventional configuration has the following problems.
That is, in the first and second conventional configurations, when the male screw portion of the check valve is screwed into the female screw portion of the pump housing and those components are screwed together, chips generated at the screw fastening portion are generated. Such foreign matter enters the fuel flow path in the pump housing and the check valve. Therefore, during the subsequent operation of the high-pressure fuel pump, the foreign matter may be carried to the pump side or the fuel injection valve side and caught in the sliding part, or the flow path may be blocked, resulting in malfunction or seizure. It was.
[0006]
In order to prevent such a problem, in the first and second conventional configurations, the deburring operation is performed on the female screw portion and the male screw portion prior to the screw fastening of the check valve to the pump housing. After tightening the screws, the presence or absence of foreign matter in the flow path was inspected. For this reason, there has been a problem that productivity is deteriorated because a large number of man-hours are required for the deburring operation of both screw portions and the inspection after screw fastening.
[0007]
In the first conventional configuration, a gasket is interposed between the inner bottom surface of the mounting hole of the pump housing and the tip of the check valve, and the screw fastening portion between the female screw portion and the male screw portion is located on the inner end side. It is sealed with. For this reason, when screwing the male screw part of the check valve into the female screw part of the pump housing and fastening those parts, the screw fastening force is applied to the inner bottom surface of the mounting hole via the gasket, There has been a problem that distortion is generated in the cylinder wall disposed inside the cylinder wall.
[0008]
On the other hand, in the second conventional configuration, a gasket is interposed between the peripheral edge of the opening end of the mounting hole of the pump housing and the outer periphery of the base end of the male threaded portion of the check valve. The screw fastening portion is sealed on the outer end side. Therefore, when the male screw portion of the check valve is screwed into the female screw portion of the pump housing and these parts are screwed together, a space is formed between the tip portion of the check valve and the inner bottom surface of the mounting hole. Thus, the screw fastening force does not act on the inner bottom surface of the mounting hole, and there is no possibility of causing distortion in the cylinder wall.
[0009]
However, in this second conventional configuration, the space formed between the tip of the check valve and the inner bottom surface of the mounting hole communicates with the pressurizing space including the pressurizing chamber in the pump housing. For this reason, there was a problem that the dead volume of the pressurizing chamber was increased, and the fuel volume shrinkage at the time of high pressure was increased correspondingly, resulting in a decrease in discharge efficiency.
[0010]
The present invention has been made paying attention to such problems existing in the prior art. The purpose is that when the male screw part of the second part is screwed to the female screw part of the first part and both parts are screwed, foreign matter such as chips generated at the screw fastening part is An object of the present invention is to provide a screw fastening component mounting structure that can prevent the fluid from entering the fluid flow path.
[0011]
Another object of the present invention is to prevent a cylinder wall from being distorted when a check valve is screwed to a pump housing in a high-pressure fuel pump. It is an object of the present invention to provide a screw fastening part mounting structure that can reduce the size of the pump and improve the discharge efficiency of the pump.
[0012]
[Means for Solving the Problems]
In the following, means for achieving the above object and its effects are described.
According to the first aspect of the present invention, the male screw portion formed on the outer peripheral surface of the second component is screwed with the female screw portion formed on the inner peripheral surface of the mounting hole of the first component, By fastening the parts, the first flow path of the fluid provided in the first part and the second flow path of the fluid provided in the second part are connected, and the mounting hole of the first part In a mounting structure for a screw fastening part in which a sealing means is provided between the peripheral edge of the opening end of the first part and the outer periphery of the base end of the male thread part of the second part, the tip part of the second part and the inside of the mounting hole of the first part A partition member for partitioning between the female screw portion and the screw fastening portion of the male screw portion and both flow paths between the bottom surface and the bottom surface The partition member includes a cylindrical part extending along the inner peripheral surface of the second flow path of the second part, a first contact part that contacts the tip part of the second part, and the first part A second contact portion that contacts the inner bottom surface of the mounting hole, and a connection portion that connects between both contact portions and is plastically deformable along the extending direction of the flow path. It is characterized by this.
[0013]
Therefore, according to the first aspect of the present invention, when the male screw portion of the second component is screwed into the female screw portion of the first component and the both components are screwed together, the screw is generated at the screw fastening portion. The partition member can surely suppress foreign matter such as chips from entering the fluid flow paths in both parts. Therefore, prior to screw fastening of the second part to the first part, deburring work is performed on the female screw part and the male screw part, or whether or not foreign matter is mixed in the flow path after screw fastening of both parts. There is no need to inspect, and man-hours can be reduced to improve productivity.
[0015]
Moreover, A partition member with a simple structure can securely partition between the screw fastening portion and both flow paths, and foreign matter such as chips generated in the screw fastening section is mixed into the fluid flow paths in both parts. Can be effectively prevented.
[0016]
Claim 2 The invention described in claim 1 In the invention described in item 1, the second contact portion is formed in a convex shape toward the inner bottom surface side of the mounting hole.
[0017]
Therefore, the claims 2 According to the invention described in (2), the convex second contact portion is plastically deformed while contacting the inner bottom surface of the mounting hole without being caught, so that the gap between the screw fastening portion and the two flow paths can be further ensured. Can be partitioned.
[0018]
Claim 3 The invention described in claim 1 Or claim 2 In the invention described in item 2, the second part has a check valve function.
Therefore, the claims 3 In the mounting structure in which the second part having the check valve function is screw-fastened to the first part such as the housing, foreign matter such as chips generated at the screw fastening portion is caused by the fluid in both parts. It is possible to effectively prevent mixing in the flow path.
[0019]
Claim 4 The invention described in claim 1 to claim 1 3 The first component is a pump housing of a high-pressure fuel pump, and the second component is provided in the middle of the high-pressure fuel passage from the pressurizing chamber to the fuel injection valve in the pump housing. The check valve is characterized in that it is a check valve.
[0020]
Therefore, the claims 4 In the high-pressure fuel pump, when the check valve is screwed to the pump housing, foreign matter such as chips generated in the screw fastening portion is caused by the flow path of the fuel in the pump housing and the check valve. It can be reliably suppressed by the partition member. In addition, when the check valve is screw-fastened to the pump housing, since no screw fastening force is applied to the inner bottom surface of the mounting hole, it is possible to prevent the cylinder wall from being distorted. Furthermore, the space formed between the tip of the check valve and the inner bottom surface of the mounting hole is partitioned and separated from the pressurizing space including the pressurizing chamber in the pump housing by the partition member. The dead volume can be reduced, and the discharge efficiency of the pump can be improved.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
A first embodiment in which the present invention is embodied in a check valve mounting structure for a pump housing of a high-pressure fuel pump will be described below with reference to FIGS.
[0022]
As shown in FIG. 1, in this high-pressure fuel pump 11, a cylinder 13 is disposed in a pump housing 12, and a pressurizing chamber 14 is formed inside the tip side. A plunger 15 is fitted and supported in the cylinder 13 so as to be slidable back and forth in the axial direction of the cylinder 13. As the camshaft (not shown) rotates, the plunger 15 is reciprocated according to the cam surface shape of a driving cam (not shown) provided on the camshaft.
[0023]
A fuel supply passage 16 is formed in the pump housing 12 so as to communicate with the pressurizing chamber 14. An electromagnetic spill valve 17 is disposed in the fuel supply passage 16 and is opened and closed under the control of an electronic control device (not shown). When the plunger 15 is lowered in a state where the electromagnetic spill valve 17 is opened, the low-pressure fuel as fluid flows from a fuel tank (not shown) through a fuel pump (not shown) and a fuel supply passage 16 to the pressurizing chamber 14. Inhaled. When the electromagnetic spill valve 17 is closed when the plunger 15 is raised, the volume of the pressurizing chamber 14 is reduced and the fuel inside thereof is pressurized.
[0024]
A first flow path 18 for pumping high pressure fuel as a fluid is formed in the cylinder 13 and the pump housing 12 so as to communicate with the pressurizing chamber 14, and a check valve is provided in the first flow path 18. 19 is connected. And the force which pushes the valve body 26 toward the downstream side with the pressure of the high pressure fuel pumped from the inside of the pressurization chamber 14 via the 1st flow path 18 is based on the elastic force of the spring 27, and the pressure of the fuel downstream of a valve. When the force pushing the valve body 26 toward the upstream side is exceeded, the check valve 19 is opened. As a result, the high pressure fuel is supplied from the first flow path 18 through the check valve 19 to a fuel distribution pipe (not shown) and distributed to each fuel injection valve attached to the cylinder head of the engine. Yes.
[0025]
Next, the mounting structure of the check valve 19 to the pump housing 12 will be described.
As shown in FIGS. 1 and 3, a boss portion 21 projects from the side surface of the pump housing 12 as the first component. A mounting hole 22 is formed at the center of the boss portion 21, and a female screw portion 23 is formed on the inner peripheral surface of the mounting hole 22. The end of the first flow path 18 is opened at the center of the inner bottom surface 22 a of the mounting hole 22.
[0026]
A check valve 19 as a second part attached to the attachment hole 22 of the pump housing 12 includes a valve casing 24, a seat body 25 fitted in the valve casing 24, and a contact movement of the seat body 25. The valve body 26 is disposed so as to be opposed to each other, and a spring 27 that biases the valve body 26 toward the pressure contact position with respect to the seat body 25. And this check valve 19 is the state which inserted the spring 27, the valve body 26, and the sheet | seat body 25 in the valve casing 24 in order, and caulked the edge of the valve casing 24, and formed the crimp part 28, It is assembled integrally.
[0027]
A male screw portion 29 is formed on the outer peripheral surface of the valve casing 24 of the check valve 19, and a step surface 24 a is formed at the outer peripheral central portion of the valve casing 24 so as to correspond to the base end portion of the male screw portion 29. Is formed. The male screw portion 29 of the check valve 19 is screwed into the female screw portion 23 of the pump housing 12, whereby the check valve 19 is screwed into the mounting hole 22 of the pump housing 12. In this state, the second flow path 30 for high-pressure fuel provided at the center of the seat body 25 of the check valve 19 is connected to the first flow path 18 of the pump housing 12.
[0028]
An annular gasket 31 serving as a sealing means is fitted on the outer periphery of the male threaded portion 29 of the check valve 19, and the opening end periphery of the mounting hole 22 of the pump housing 12 and the stepped surface 24 a on the valve casing 24. It is interposed between. The gasket 31 is configured to seal the screw fastening portion between the female screw portion 23 and the male screw portion 29 on the outer end side.
[0029]
As shown in FIGS. 1 to 3, a metal partition member 32 is interposed between the tip of the check valve 19 and the inner bottom surface 22 a of the mounting hole 22 of the pump housing 12. The partition member 32 partitions between the screw fastening portions of the female screw portion 23 and the male screw portion 29 and the first and second flow paths 18 and 30.
[0030]
The partition member 32 includes a cylindrical portion 33 that extends along the inner peripheral surface of the second flow path 30 of the check valve 19, a first contact portion 34 that contacts the tip of the check valve 19, and the pump housing 12. The second contact portion 35 that contacts the inner bottom surface 22a of the mounting hole 22 and the connection portion 36 that connects the contact portions 34 and 35 are configured. The first contact portion 34 is formed in a flat surface shape so as to come into surface contact with the tip portion of the check valve 19, and the second contact portion 35 is formed in an arc convex shape toward the inner bottom surface 22 a side of the mounting hole 22. Yes.
[0031]
Further, the connecting portion 36 of the partition member 32 is plastically deformed along the extending direction of the flow paths 18 and 30 when the female screw portion 23 and the male screw portion 29 are fastened, and the contact portions 34 and 35 are formed. The tip end of the check valve 19 and the inner bottom surface 22a of the mounting hole 22 are brought into close contact with each other. Further, a gap S1 between the outer peripheral surface of the cylindrical portion 33 of the partition member 32 and the inner peripheral surface of the second flow path 30 of the check valve 19 is a screw fastening portion between the female screw portion 23 and the male screw portion 29. Is set to be smaller than the size of foreign matter that may cause trouble when mixed into the first and second flow paths 18 and 30.
[0032]
Next, the attachment method of the check valve 19 to the pump housing 12 configured as described above will be described with reference to FIG.
Now, at the time of this assembly, the pump housing 12 is disposed with the mounting hole 22 facing upward, and the partition member 32 is inserted on the inner bottom surface 22 a of the mounting hole 22. Thereafter, the male threaded portion 29 is screwed into the female threaded portion 23 of the mounting hole 22 of the pump housing 12 in a state where the gasket 31 is fitted on the outer periphery of the proximal end of the male threaded portion 29 of the check valve 19.
[0033]
In this case, as indicated by a chain line in FIG. 3, the second contact portion 35 of the partition member 32 contacts the inner bottom surface 22 a of the mounting hole 22, and the first flow path 18 of the pump housing 12 is connected to the female screw portion 23 and the male screw portion 23. It is shielded from the screw fastening portion with the screw portion 29. Therefore, even if foreign matter such as chips is generated at the screw fastening portion when the male screw portion 29 is screwed to the female screw portion 23, there is no possibility that the foreign matter is mixed into the first flow path 18 below.
[0034]
Further, when the male screw portion 29 is screwed into the female screw portion 23, the tubular portion 33 of the partition member 32 gradually enters the second flow path 30 of the check valve 19, and the check valve 19 The two flow paths 30 are shielded from the screw fastening portion between the female screw portion 23 and the male screw portion 29. Therefore, there is no possibility that foreign matters such as chips generated at the screw fastening portion are mixed into the upper second flow path 30.
[0035]
Thus, when the screwing of the male screw portion 29 to the female screw portion 23 is completed, the check valve 19 is screwed into the mounting hole 22 of the pump housing 12 as shown in FIG. The first flow path 18 and the second flow path 30 of the check valve 19 are connected. In this state, the gasket 31 is sandwiched between the peripheral edge of the opening end of the mounting hole 22 and the step surface 24a on the check valve 19, and the screw fastening portion between the female screw portion 23 and the male screw portion 29 is the outer end. Sealed on the part side.
[0036]
Further, in the screw fastening state of the check valve 19 with respect to the pump housing 12, the connection portion 36 of the partition member 32 is plastically deformed along the extending direction of the flow paths 18 and 30, and the first contact portion 34 is checked. The second contact portion 35 is in close contact with the inner bottom surface 22 a of the mounting hole 22. Accordingly, the first and second flow paths 18 and 30 are shielded from the screw fastening portion between the female screw portion 23 and the male screw portion 29. For this reason, even if foreign matter such as chips generated at the screw fastening portion is accumulated in the space S <b> 2 between the front end portion of the check valve 19 and the inner bottom surface 22 a of the mounting hole 22, the foreign matter remains in the high-pressure fuel pump 11. There is no possibility of mixing into the first and second flow paths 18 and 30 during operation.
[0037]
Therefore, according to this embodiment, the following effects can be obtained.
(1) In this mounting structure of the screw fastening component, a female screw portion 23 is formed on the inner peripheral surface of the mounting hole 22 of the pump housing 12 and a male screw portion 29 is formed on the outer peripheral surface of the check valve 19. ing. Then, the female screw portion 23 is screwed into the male screw portion 29 and the check valve 19 is fastened to the pump housing 12, whereby the first flow path 18 of the fuel provided in the pump housing 12. Is connected to the second flow path 30 of the fuel provided inside the check valve 19. Further, a gasket 31 is disposed between the peripheral edge of the opening end of the mounting hole 22 of the pump housing 12 and the outer periphery of the base end of the male threaded portion 29 of the check valve 19. The screw fastening portion with the portion 29 is sealed. Further, between the distal end portion of the check valve 19 and the inner bottom surface 22 a of the mounting hole 22 of the pump housing 12, between the screw fastening portions of the female screw portion 23 and the male screw portion 29 and both flow paths 18, 30. A partition member 32 for partitioning is interposed.
[0038]
For this reason, when the male screw portion 29 of the check valve 19 is screwed into the female screw portion 23 of the pump housing 12 and the both parts 12 and 19 are screwed together, chips and the like generated at the screw fastening portion are removed. The partition member 32 can reliably suppress foreign matters from being mixed into the fuel flow path in the pump housing 12 and the check valve 19. Therefore, prior to the fastening of the check valve 19 with respect to the pump housing 12, deburring is performed on the female screw portion 23 and the male screw portion 29, or both the parts 12 and 19 are screwed into the flow path. There is no need to inspect the presence or absence of foreign matter, and man-hours can be reduced to improve productivity.
[0039]
Further, when the check valve 19 is screwed to the pump housing 12, the tip end portion of the check valve 19 is not pressed against the inner bottom surface 22 a of the mounting hole 22, so that the screw fastening force is applied to the inner bottom surface 22 a of the mounting hole 22. It is not possible to prevent the inner wall of the cylinder 13 from being distorted. Further, the space S2 formed between the tip of the check valve 19 and the inner bottom surface 22a of the mounting hole 22 is partitioned and separated from the pressurizing space including the pressurizing chamber 14 in the pump housing 12 by the partition member 32. Therefore, the dead volume of the pressurizing chamber 14 can be reduced, and the discharge efficiency of the high-pressure fuel pump 11 can be improved.
[0040]
(2) In this screw fastening component mounting structure, the partition member 32 includes a cylindrical portion 33 extending along the inner peripheral surface of the second flow path 30 of the check valve 19 and a tip portion of the check valve 19. The first contact portion 34 that contacts the inner surface 22a, the second contact portion 35 that contacts the inner bottom surface 22a of the mounting hole 22 of the pump housing 12, and the contact portions 34 and 35 are connected to each other and along the extending direction of the flow path. And a connecting portion 36 that can be plastically deformed. For this reason, the partition member 32 having a simple structure can reliably partition the screw fastening portion and the two flow paths 18, 30, and foreign matter such as chips generated in the screw fastening portion can be separated from both the parts 12, It is possible to effectively prevent the fuel from flowing into the fuel flow paths 18 and 30 in the fuel tank 19.
[0041]
(3) In the mounting structure of the screw fastening component, the second contact portion 35 is formed in a circular arc shape toward the inner bottom surface 22 a side of the mounting hole 22. For this reason, the arc-shaped convex second contact portion 35 is plastically deformed while being brought into contact with the inner bottom surface 22a of the mounting hole 22 without being caught, and the gap between the screw fastening portion and both the flow passages 18 and 30 is further ensured. Can be partitioned.
[0042]
(4) In this screw fastening component mounting structure, the gap S1 between the outer peripheral surface of the cylindrical portion 33 of the partition member 32 and the inner peripheral surface of the second flow path 30 in the check valve 19 is a fuel. It is set to be smaller than the size of foreign matter that may be mixed in the flow paths 18 and 30 and cause trouble. For this reason, in the middle of fastening the male screw portion 29 of the check valve 19 to the female screw portion 23 of the pump housing 12, a foreign material having a size larger than a specific size is brought into contact with the outer peripheral surface of the cylindrical portion 33 of the partition member 32. Intrusion into the second flow path 30 of the check valve 19 can be reliably suppressed via the gap S1 between the inner peripheral surface of the second flow path 30 in the valve 19.
[0043]
(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, the same or similar components as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment to avoid redundant description, and detailed description thereof is omitted. To do.
[0044]
In this embodiment, a substantially frustoconical regulation protrusion 40 as a regulation means is formed at the center of the inner bottom surface 22 a of the mounting hole 22 of the pump housing 12. When the partition member 32 is inserted on the inner bottom surface 22 a of the mounting hole 22 of the pump housing 12, the connection portion 36 of the partition member 32 is engaged with the restricting protrusion 40, and the axis of the tubular portion 33 is non-returned. The position of the partition member 32 is regulated so as to substantially coincide with the axis of the second flow path 30 of the valve 19. Accordingly, when the male screw portion 29 of the check valve 19 is screwed to the female screw portion 23 of the pump housing 12, the partition member 32 may be displaced in a direction intersecting the extending direction of the second flow path 30. It is suppressed.
[0045]
Therefore, according to the second embodiment, in addition to the effects described in (1) to (4) in the first embodiment, the following effects can be obtained.
(5) In the mounting structure of the screw fastening component, the restriction protrusion 40 is provided on the inner bottom surface 22a of the attachment hole 22 of the pump housing 12, and the restriction protrusion 40 is engaged with the partition member 32. The position of the partition member 32 is regulated in a direction intersecting with the extending direction of the second flow path 30 in the check valve 19. For this reason, when the male threaded portion 29 of the check valve 19 is screwed to the female threaded portion 23 of the pump housing 12 with the partitioning member 32 inserted into the mounting hole 22 of the pump housing 12, the partitioning member 32 is It is possible to suppress displacement in a direction intersecting with the extending direction of the two flow paths 30. Therefore, the partition member 32 can more reliably partition between the screw fastening portion and both the flow paths 18 and 30, and foreign matters such as chips generated at the screw fastening portion are contained in the pump housing 12 and the check valve 19. It is possible to effectively prevent the second flow path 30 from being mixed.
[0046]
(Example of change)
In addition, this embodiment is not limited to said structure, You may change as follows. Even when configured in this manner, the same operations and effects as those of the above-described embodiments can be obtained.
[0047]
In each of the above embodiments, the end edge of the valve casing 24 of the check valve 19 is fixed to the seat body 25 by caulking, but this is fixed by other methods such as welding. May be.
[0048]
In each of the above embodiments, the check valve 19 is attached to the pump housing 12 of the high-pressure fuel pump 11, but this is applied to a screw fastening part attachment structure in a product different from the high-pressure fuel pump 11. May be used.
[0049]
Further, other technical ideas that can be grasped from the above embodiments will be described below together with the effects thereof.
(A) A regulating means for regulating the position of the partition member in a direction intersecting with the extending direction of the flow path in the second part is provided between the inner bottom surface of the mounting hole and the partition member. The attachment structure of the screw fastening component as described in any one of Claims 1-5. Therefore, according to this configuration, when the male screw portion of the second component is screwed to the female screw portion of the first component with the partition member inserted into the mounting hole of the first component, It is possible to suppress displacement in a direction intersecting with the extending direction of the flow path. Therefore, the partition member can more reliably partition between the screw fastening portion and both flow paths, and foreign matter such as chips generated in the screw fastening portion can be mixed into the fluid flow paths in both parts. It can be effectively prevented. Further, the end portion of the sheet body 25 and the end portion of the tubular portion 33 of the partition member 32 can be provided without chamfering the end portion of the sheet body 25 and the end portion of the tubular portion 33 of the partition member 32. Interference can be prevented.
[0050]
(B) There is a possibility that a gap between the outer peripheral surface of the cylindrical portion of the partition member and the inner peripheral surface of the second flow path in the second part may be mixed into the flow path of the fluid and cause trouble. The screw fastening component mounting structure according to any one of claims 2 to 5 and (a), wherein the mounting structure is set to be smaller than the size of the foreign matter. Therefore, according to this configuration, in the middle of fastening the male screw portion of the second component to the female screw portion of the first component, a foreign material having a size greater than a specific size is formed between the outer peripheral surface of the cylindrical portion of the partition member and the second portion. Intrusion into the flow path of the second component can be reliably suppressed through a gap between the inner peripheral surface of the second flow path in the component.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a first embodiment of a check valve mounting structure for a pump housing of a high-pressure fuel pump embodying the present invention.
2 is a perspective view showing a partition member in the check valve mounting structure of FIG. 1; FIG.
FIG. 3 is a partial cross-sectional view showing the check valve mounting structure of FIG. 1 in an exploded manner.
FIG. 4 is a cross-sectional view showing a second embodiment of a check valve mounting structure for a pump housing.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... High pressure fuel pump, 12 ... Pump housing as 1st component, 13 ... Cylinder, 14 ... Pressurization chamber, 15 ... Plunger, 18 ... 1st flow path, 19 ... Check valve as 2nd component, 22 ... Mounting hole, 22a ... inner bottom surface, 23 ... female screw part, 24 ... valve casing, 25 ... sheet body, 26 ... valve body, 27 ... spring, 29 ... male screw part, 30 ... second flow path, 31 ... sealing means Gasket, 32 ... partition member, 33 ... cylindrical part, 34 ... first contact part, 35 ... second contact part, 36 ... connection part, 40 ... regulation protrusion as regulation means, S1 ... gap.

Claims

By screwing the male screw portion formed on the outer peripheral surface of the second component to the female screw portion formed on the inner peripheral surface of the mounting hole of the first component, and fastening both components, The fluid first flow path provided in the part and the fluid second flow path provided in the second part are connected to each other. In the mounting structure of the screw fastening part formed by sealing means between the base end outer periphery of the male screw part,
A partition member is provided between the distal end portion of the second component and the inner bottom surface of the mounting hole of the first component to partition between the female screw portion and the screw fastening portion of the male screw portion and both flow paths. Become
The partition member includes a cylindrical portion that extends along the inner peripheral surface of the second flow path of the second component, a first contact portion that contacts the distal end portion of the second component, and an inner bottom surface of the mounting hole of the first component. A screw fastening component comprising: a second contact portion that contacts the second contact portion; and a connection portion that connects between the contact portions and is plastically deformable along an extending direction of the flow path . Mounting structure.

2. The screw fastening component mounting structure according to claim 1, wherein the second contact portion is formed in a convex shape toward the inner bottom surface side of the mounting hole .

The mounting structure for a screw fastening part according to claim 1 or 2, wherein the second part has a check valve function .

The first part is a pump housing of a high-pressure fuel pump, and the second part is a check valve provided in the middle of a high-pressure fuel passage from a pressurizing chamber in the pump housing to a fuel injection valve. The attachment structure of the screw fastening component as described in any one of Claims 1-3.