JP3539241B2

JP3539241B2 - Valve train for internal combustion engine

Info

Publication number: JP3539241B2
Application number: JP33148198A
Authority: JP
Inventors: 太郎上野
Original assignee: Nissan Motor Co Ltd
Current assignee: Nissan Motor Co Ltd
Priority date: 1998-11-20
Filing date: 1998-11-20
Publication date: 2004-07-07
Anticipated expiration: 2018-11-20
Also published as: JP2000161033A

Description

【０００１】
【発明の属する技術分野】
本発明は内燃機関の動弁装置、とりわけ、吸，排気弁を電磁的に開閉するようにした動弁装置に関する。
【０００２】
【従来の技術】
車両用エンジンの吸，排気弁を電磁的に開閉するようにした動弁装置は各種公知であるが、中でも特開平１０−１４１０２８号公報に示されているように、アーマチュアのストロークエンドで該アーマチュアと電磁石との間にダンパ室を構成するようにして、アーマチュアによる該ダンパ室の空気の圧縮作用で電磁石へのアーマチュア着座時に緩衝効果を得るようにしたものや、特開平５−３４０２２３号公報に示されているように、電磁石にピストンと該ピストンの底部を押圧するばねとを設けると共に、ピストン配設部の底部の空間部に磁性粉末を収納して、電磁石へのアーマチュア着座時にピストンによるばねおよび磁性粉末の圧縮作用で緩衝効果を得るようにしたものが知られている。
【０００３】
【発明が解決しようとする課題】
前記何れの装置にあっても、空気の圧縮作用、又はばねおよび磁性粉末の圧縮作用でアーマチュア着座時の緩衝を行わせるため、この緩衝作用時にアーマチュアの変位に伴ってアーマチュアに作用する圧縮反力が増加し、従って、電磁石にはこの圧縮反力に打ち勝つ電磁力が得られるように、比較的大きなキャッチング電流およびホールド電流を供給する必要があって、バッテリの消費電力が大きくなってしまう。
【０００４】
そこで、本発明は電磁石のキャッチング電流およびホールド電流の増大化を伴うことなくアーマチュア着座時の緩衝効果が得られて、バッテリ消費電力を節減することができる内燃機関の動弁装置を提供するものである。
【０００５】
【課題を解決するための手段】
請求項１の発明にあっては、吸，排気弁の各弁軸に連設されたアーマチュアと、該アーマチュアの上下面に対向して配設された２つの電磁石と、前記弁軸を開弁側と閉弁側とに付勢する２つのばね部材とを備え、吸，排気弁をこれら電磁石とばね部材との協働により電磁的に開閉するようにした内燃機関の動弁装置において、前記各電磁弁のコアに、アーマチュアが着座する吸着面から出没するピストンと、ピストン背部で作動油を貯留した作動油室と、作動油室に連なって設けられてピストンの押動で作動油室から流出する作動油の流通に抵抗を付与する抵抗通路と、を備えたショックアブソーバを設けつつ、各電磁石のコアに設けたショックアブソーバの作動油室を抵抗通路で連通したことを特徴としている。
【０００７】
請求項２の発明にあっては、請求項１に記載の抵抗通路にダンピング力調整用のオリフィスを設け、かつ、該抵抗通路にオリフィスをバイパスするバイパス通路を設けると共に、該バイパス通路と抵抗通路との連接部の一方に、動弁装置の冷機時にオリフィスへの作動油の流通を遮断してバイパス通路を開放し、動弁装置の暖機完了後はバイパス通路を遮断してオリフィスへの作動油の流通を許容する切換弁を設けたことを特徴としている。
【０００８】
請求項３の発明にあっては、請求項１に記載の抵抗通路に動弁装置の温度条件に応じてオリフィス径を可変制御するダンピング力調整用の可変オリフィスを設け、動弁装置の冷機時に相当する所定温度以下ではオリフィス径を最大に拡大するようにしたことを特徴としている。
【０００９】
請求項４の発明にあっては、吸，排気弁の各弁軸に連設されたアーマチュアと、該アーマチュアの上下面に対向して配設された２つの電磁石と、前記弁軸を開弁側と閉弁側とに付勢する２つのばね部材とを備え、吸，排気弁をこれら電磁石とばね部材との協働により電磁的に開閉するようにした内燃機関の動弁装置において、前記各電磁弁のコアに、アーマチュアが着座する吸着面から出没するピストンと、ピストン背部で作動油を貯留した作動油室と、作動油室に連なって設けられてピストンの押動で作動油室から流出する作動油の流通に抵抗を付与する抵抗通路と、を備えたショックアブソーバを設けつつ、抵抗通路を外部に開放する一方、作動油室に作動油補給通路を設け、かつ、これら抵抗通路と作動油補給通路にそれぞれ開閉弁を設け、これら開閉弁の作動制御により動弁装置の冷機時に抵抗通路を開放状態に維持させる一方、作動油補給通路を遮断状態に維持させ、動弁装置の暖機完了後はこれら開閉弁を電磁石の励・消磁に応じて開・閉制御して作動油補給通路から作動油室への作動油補給と、作動油室から抵抗通路への作動油流出による緩衝作用とを行わせるようにしたことを特徴としている。
【００１０】
【発明の効果】
請求項１に記載の発明によれば、アーマチュアが電磁石の電磁力によってコアの吸着面に着座する直前でショックアブソーバのピストンに当接して該ピストンを押動すると、このピストンの押動により作動油室の作動油が抵抗通路へ流出して該抵抗通路を流通することにより流通抵抗が発生し、前記アーマチュアを制動して着座時の衝撃を緩和してアーマチュア着座時の衝接音を低減し、音振性能を向上することができると共に、アーマチュアおよび電磁石のコアの摩耗を抑制することができる。
【００１１】
また、前記アーマチュア着座時におけるショックアブソーバのピストンの押動作用には、作動油室から抵抗通路へ作動油が流通抵抗を受けて流通するだけで、アーマチュアの変位に比例的な反力増大が生じることがなく、しかも、アーマチュアがコアの吸着面に着座してピストンがフルストロークして停止するとアーマチュアへの反力が消失するため、電磁石へのキャッチング電流およびホールド電流を低下させることができて、バッテリ消費電力を節減することができる。
【００１２】
さらに、上，下２つの電磁石に設けたショックアブソーバのそれぞれの作動油室を抵抗通路で連通してあるから、一方のショックアブソーバの緩衝作動時には該一方のショックアブソーバの作動油室から流出した作動油が、他方のショックアブソーバの作動油室に流入して該他方のショックアブソーバを伸張作動させて必ず緩衝態勢に整えるため、簡単な構造でエンジン高回転時の追従性を高めることができる。
【００１３】
請求項２に記載の発明によれば、請求項１の発明の効果に加えて、作動油の粘性が大きくなる動弁装置の冷機時には、一方のショックアブソーバの緩衝作動時には該一方のショックアブソーバの作動油室から流出した作動油が抵抗通路に設けたダンピング力調整用のオリフィスを通らずに、該オリフィスをバイパスしたバイパス通路を通って他方のショックアブソーバの作動油室に流入するため、作動油の粘性増大による流通抵抗の増大化を抑制することができて、動弁装置の冷機時における初期化作動をスムーズに行わせることができると共に、初期化時のバッテリ消費電力を節減することができる。
【００１４】
請求項３に記載の発明によれば、請求項１の発明の効果に加えて、作動油の粘性が大きくなる動弁装置の冷機時には、抵抗通路に設けたダンピング力調整用の可変オリフィスのオリフィス径を最大に拡大するため、作動油の粘性増大による流通抵抗の増大化を抑制することができて、動弁装置の冷機時における初期化作動をスムーズに行わせることができると共に、初期化時のバッテリ消費電力を節減することができる。
【００１５】
また、動弁装置の暖機完了後は作動油の温度条件に応じて可変オリフィスのオリフィス径を変化させて、作動油の流通抵抗を調整できるため、作動油の温度変化に伴う微妙な粘性変化の影響を受けることなく適切な緩衝作用を行わせることができる。
【００１６】
請求項４に記載の発明によれば、アーマチュアが電磁石の電磁力によってコアの吸着面に着座する直前でショックアブソーバのピストンに当接して該ピストンを押動すると、このピストンの押動により作動油室の作動油が抵抗通路へ流出して該抵抗通路を流通することにより流通抵抗が発生し、前記アーマチュアを制動して着座時の衝撃を緩和してアーマチュア着座時の衝接音を低減し、音振性能を向上することができると共に、アーマチュアおよび電磁石のコアの摩耗を抑制することができる。
また、作動油の粘性が大きくなる動弁装置の冷機時には、外部開放の抵抗通路および作動油室に設けた作動油補給通路の各開閉弁の作動制御により、該抵抗通路が開放状態に維持される一方、作動油補給通路が遮断状態に維持されて作動油室を空の状態にしておくことができるため、ピストンの押動によるアーマチュアへの反力を消失させることができて、動弁装置の冷機時における初期化作動をスムーズに行わせることができると共に、初期化時のバッテリ消費電力を節減することができる。
【００１７】
【発明の実施の形態】
以下、本発明の一実施形態を図面と共に詳述する。
【００１８】
図１において、１は吸気弁又は排気弁等の弁体、２は該弁体１の動弁装置を示す。
【００１９】
動弁装置２は前記弁体１の弁軸１ａに連設した磁性金属材料からなるアーマチュア４と、コア５ａ，６ａおよび励磁コイル５ｂ，６ｂを備えて前記アーマチュア４の上下面に対向して配設した開弁側および閉弁側の２つの電磁石５，６と、前記弁軸１ａを開弁側と閉弁側とに付勢する２つのばね部材としてのコイルスプリング７，８とを備えている。
【００２０】
コイルスプリング７，８は電磁石５，６が消磁している状態では弁体１が中間リフト位置を保持するように所要の平衡したばね力に設定し、電磁石５，６はこれらコイルスプリング７，８のばね力の大きさに適応した大きさの電磁力が得られるように設定して、これら電磁石５，６の電磁力とコイルスプリング７，８のばね力との協働によって弁体１を開閉するようにしてある。
【００２１】
アーマチュア４はその下面中心位置に固設したアーマチュア軸４ａを備え、該アーマチュア軸４ａの下端を前記弁軸１ａの上端に嵌挿したコンタクト４ｂに当接して該弁軸１ａに連設してある。
【００２２】
アーマチュア４の上面中央には上側の可動側スプリングシート９に固設したばね軸９ａの下端が当接し、開弁側のコイルスプリング７はハウジング３の上壁に固設した固定側スプリングシート１０と該可動側スプリングシート９との間に弾装してある。
【００２３】
閉弁側のコイルスプリング８はシリンダヘッド１１に設けた凹部１１ａ内に配置して、弁軸１ａに固設した可動側スプリングシート１２と凹部１１ａの底面に固設した固定側スプリングシート１３との間に弾装してある。
【００２４】
そして、前記開弁側および閉弁側の電磁石５，６にアーマチュア４の着座時の衝撃を緩和するショックアブソーバ２０，２１を設けてある。
【００２５】
これらショックアブソーバ２０，２１は、図２にも示すように電磁石５，６のコア５ａ，６ａに設けられてそれらのアーマチュア吸着面から出没するピストン２２，２３と、これらピストン２２，２３の背部で作動油を貯留した作動油室２４，２５と、これら作動油室２４，２５に連なって設けられてピストン２２，２３の押動で作動油室２４，２５から流出する作動油の流通に抵抗を付与する抵抗通路２６とを備え、本実施形態ではこの抵抗通路２６により前記両作動油室２４，２５を連通している。
【００２６】
抵抗通路２６にはダンピング力調整用のオリフィス２７を設けてあると共に、チェックバルブ２９を備えた作動油補給通路２８を接続して、該作動油補給通路２８から作動油を補給できるようにしてある。
【００２７】
図１中、１４はバルブシートを示す。
【００２８】
以上の実施形態の構造によれば、開弁側電磁石５の励磁コイル５ｂと閉弁側電磁石６の励磁コイル６ｂとに、アーマチュア４を吸着するためのキャッチング電流および該アーマチュア４を着座保持するためのホールド電流をそれぞれ交互に供給して、該アーマチュア４のコア５ａの吸着面への吸引，着座と、コア６ａの吸着面への吸引，着座とを交互に繰り返すことによって弁体１が開閉される。
【００２９】
ここで、前記コア５ａ，６ａにアーマチュア４が着座する際、例えばアーマチュア４が図２に示すように閉弁側電磁石６のコア６ａに着座する直前で、該アーマチュア４がショックアブソーバ２１のピストン２３に当接して該ピストン２３を押圧すると、このピストン２３の押動により作動油室２５の作動油が抵抗通路２６へ流出して該抵抗通路２６を流通することにより流通抵抗が発生し、前記アーマチュア４を制動する。
【００３０】
この結果、アーマチュア４のコア６ａへの着座時の衝撃を緩和して該着座時の衝接音を低減する。
【００３１】
アーマチュア４の開弁側電磁石５のコア５ａへの着座の際にも、同様にショックアブソーバ２０のピストン２２の押動により作動油室２４から作動油を抵抗通路２６へ流出させ、流通抵抗を発生させることによりアーマチュア４を制動して、コア６ａへの着座時の衝撃を緩和して衝接音を低減し、従って、アーマチュア４のコア５ａ，６ａへの吸引，着座時の音振性能を向上することができると共に、アーマチュア４および電磁石５，６のコア５ａ，６ａの摩耗を抑制することができる。
【００３２】
また、前記アーマチュア４のコア５ａ，６ａへの着座時におけるショックアブソーバ２０，２１のピストン２２，２３の押動作用には、作動油室２４，２５から抵抗通路２６へ作動油が流通抵抗を受けて流通するだけで、アーマチュア４の変位に比例的な反力増大が生じることがなく、しかも、アーマチュア４がコア５ａ，６ａの吸着面に着座してピストン２２，２３がフルストロークして停止するとアーマチュア４への反力が消失するため、前記電磁石５，６へのキャッチング電流およびホールド電流を低下させることができてバッテリ消費電力を節減することができる。
【００３３】
ここで、特に本実施形態では前記上下のショックアブソーバ２０，２１の作動油室２４，２５を抵抗通路２６で連通してあるから、一方のショックアブソーバ２１の緩衝作動時には該一方のショックアブソーバ２１の作動油室２５から流出した作動油が、他方のショックアブソーバ２０の作動油室２４に流入して該他方のショックアブソーバ２０を伸張作動（ピストン２２の進出）させて必ず緩衝態勢に整えるため、簡単な構造によってエンジン高回転時の追従性を高めることができる。
【００３４】
図３は本発明の第２実施形態を示すもので、本実施形態にあっては前記図２に示した第１実施形態における抵抗通路２６にダンピング力調整用のオリフィス２７をバイパスするバイパス通路３０を設けると共に、該バイパス通路３０と抵抗通路２６との連設部の一方に、作動油の流通経路を前記オリフィス２７と、バイパス通路３０とに切換える切換弁としての３方電磁弁３１を設けてある。
【００３５】
この３方電磁弁３１は、例えば図外のシリンダヘッドオイルギャラリの作動油の温度を検出する油温センサの検出信号にもとづいてエンジンコントロールユニットにより作動制御され、動弁装置２の冷機時に相当する所定温度以下ではオリフィス２７への作動油の流通を遮断してバイパス通路３０を開放し、作動油温が前記所定温度を越えて動弁装置２の暖機完了に相当する温度にまで昇温すると、バイパス通路３０を遮断してオリフィス２７ヘの作動油の流通を許容するように切換え作動する。
【００３６】
従って、この第２実施形態の構造によれば、動弁装置２が暖機完了状態であれば３方電磁弁３１によりバイパス通路３０を遮断し、オリフィス２７への作動油の流通が許容されているため、前記第１実施形態と同様の作用効果が得られる。
【００３７】
他方、作動油の粘性が大きくなる動弁装置２の冷機時には、３方電磁弁３１によりバイパス通路３０を開放し、オリフィス２７への作動油の流通を遮断するため、例えば一方のショックアブソーバ２１の緩衝作動時には該一方のショックアブソーバ２１の作動油室２５から流出した作動油が抵抗通路２６のオリフィス２７を通らずに、該オリフィス２７をバイパスしたバイパス通路３０を通って他方のショックアブソーバ２０の作動油室２４に流入するため、作動油の粘性増大による流通抵抗の増大化を抑制することができる。
【００３８】
従って、動弁装置２の冷機時における初期化作動をスムーズに行わせることができると共に、初期化時のバッテリ消費電力を節減することができる。
【００３９】
図４は本発明の第３実施形態を示すもので、本実施形態にあっては前記図２に示した第１実施形態における抵抗通路２６のオリフィス２７に替えて、動弁装置２の温度条件に応じてオリフィス径を可変制御する可変オリフィス３２を設けてダンピング力調整を行えるようにしてある。
【００４０】
この可変オリフィス３２は、例えばサーモワックス３４を封入した感温部３３を備え、該感温部３３で作動油温度を感知してサーモワックス３４の膨脹、収縮作用でオリフィス径を変化させ、動弁装置２の冷機時に相当する所定温度以下ではオリフィス径を最大に、例えば抵抗通路２６の内径とほぼ同等にまで拡大するようにしてある。
【００４１】
従って、この第３実施形態の構造によれば、作動油の粘性が大きくなる動弁装置２の冷機時には、抵抗通路２６に設けた可変オリフィス３２のオリフィス径が該抵抗通路２６の内径とほぼ同等にまで拡大されているから、前記第２実施形態と同様に作動油の粘性増大による流通抵抗の増大化を抑制し、動弁装置２の冷機時における初期化作動をスムーズに行わせることができると共に、初期化時のバッテリ消費電力を節減することができる。
【００４２】
他方、動弁装置２の暖機完了後は作動油の温度条件に応じて可変オリフィス３２のオリフィス径を変化させて、作動油の流通抵抗を調整できるため、作動油の温度変化に伴う微妙な粘性変化の影響を受けることなく適切な緩衝作用を行わせることができる。
【００４３】
図５は本発明の第４実施形態を示すもので、この図５では便宜的に閉弁側電磁石６のコア６ａに設けられたショックアブソーバ２１を略示的に示しているが、開弁側電磁石５側のショックアブソーバ２０も以下に述べる構造と同様構造が採られる。
【００４４】
即ち、作動油室２５に連なる抵抗通路２６にはダンピング力調整用のオリフィス２７を設けてあって、該抵抗通路２６は外部のオイルリザーバ等に開放してあり、また、該作動油室２５には作動油補給通路２８を設けて該作動油補給通路２８から作動油室２５に作動油を補給するようにしてある。
【００４５】
抵抗通路２６および作動油補給通路２８には、前述したエンジンコントロールユニットにより開閉制御される開閉弁３５，３６を設けてある。
【００４６】
抵抗通路２６に設けた開閉弁３５はエンジン停止すると開弁作動され、動弁装置２の冷機時には開弁状態が維持されるが、動弁装置２が暖機完了状態であれば、励磁コイル６ｂの消磁とほぼ同時に閉弁作動され、励磁コイル６ｂの励磁とほぼ同時に開弁作動される。
【００４７】
他方、作動油補給通路２８に設けた開閉弁３６はエンジン停止すると閉弁作動され、動弁装置２の冷機時には閉弁状態が維持されるが、動弁装置２が暖機完了状態であれば、励磁コイル６ｂの消磁とほぼ同時に開弁作動されて所定圧の作動油を作動油室２５に補給してピストン２３を伸張させると共に、該作動油室２５および開閉弁３５で遮断状態にある抵抗通路２６に作動油を充満させ、励磁コイル６ｂの励磁とほぼ同時に閉弁作動される。
【００４８】
従って、この第４実施形態の構造によれば、動弁装置２の暖機完了状態では抵抗通路２６に設けた開閉弁３５および作動油補給通路２８に設けた開閉弁３６が、電磁石６の励磁コイル６ａの励・消磁に応じて開・閉作動を繰り返し、作動油補給通路２８から作動油室２５への作動油補給と、作動油室２５から抵抗通路２６への作動油流出による緩衝作用とを行わせて、前記第１実施形態と同様にキャッチング電流およびホールド電流の増大化を伴うことなくアーマチュア着座時の音振性能を向上することができる。
【００４９】
そして、エンジンを停止すると開閉弁３６が閉弁作動されて作動油補給通路２８を遮断する一方、開閉弁３５が開弁作動されて抵抗通路２６を開放させるため、エンジン停止直後の作動油室２５内の作動油温が高く粘性が低い状態の時に該作動油室２５内の作動油を抵抗通路２６から外部へ流出させて該作動油室２５内を空の状態にさせることができる。
【００５０】
従って、作動油の粘性が大きくなる動弁装置２の冷機時に、エンジン始動に先立って動弁装置２を初期化作動させた場合、前記開閉弁３５により抵抗通路２６が開放状態に維持される一方、作動油補給通路２８が遮断状態に維持されて作動油室２５を空の状態にしておくことができるため、ピストン２３の押動によるアーマチュア４への反力を消失させることができて、動弁装置２の冷機時における初期化作動をスムーズに行わせることができると共に、初期化時のバッテリ消費電力を節減することができる。
【図面の簡単な説明】
【図１】本発明の一実施形態を示す略示的断面説明図。
【図２】同実施形態の要部を示す略示的断面説明図。
【図３】本発明の第２実施形態の要部を示す略示的断面説明図。
【図４】本発明の第３実施形態の要部を示す略示的断面説明図。
【図５】本発明の第４実施形態におけるショックアブソーバを示す略示的説明図。
【符号の説明】
１弁体（吸，排気弁）
１ａ弁軸
２動弁装置
４アーマチュア
５開弁側電磁石
５ａコア
５ｂ励磁コイル
６閉弁側電磁石
６ａコア
６ｂ励磁コイル
７開弁側ばね部材
８閉弁側ばね部材
２０，２１ショックアブソーバ
２２，２３ピストン
２４，２５作動油室
２６抵抗通路
２７オリフィス
２８作動油補給通路
３０バイパス通路
３１切換弁
３２可変オリフィス
３５，３６開閉弁[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a valve train for an internal combustion engine, and more particularly, to a valve train that electromagnetically opens and closes intake and exhaust valves.
[0002]
[Prior art]
Various valve operating devices that open and close the intake and exhaust valves of a vehicle engine electromagnetically are known in the art. Among them, as disclosed in Japanese Patent Application Laid-Open No. H10-141028, the armature is provided at the stroke end of the armature. Japanese Patent Application Laid-Open No. HEI 5-340223 discloses a structure in which a damper chamber is formed between the electromagnet and the electromagnet so as to obtain a buffering effect when the armature is seated on the electromagnet by the action of compressing air in the damper chamber by the armature. As shown, a piston and a spring for pressing the bottom of the piston are provided on the electromagnet, and a magnetic powder is stored in a space at the bottom of the piston disposing portion, so that the spring by the piston is used when the armature is seated on the electromagnet. Further, there is known a magnetic powder in which a compression effect of a magnetic powder is used to obtain a buffer effect.
[0003]
[Problems to be solved by the invention]
In any of the above-described devices, a compression action of air or a compression action of a spring and magnetic powder causes the armature to be buffered when seated. Therefore, a compression reaction force acting on the armature with the displacement of the armature at the time of this buffering action. Therefore, it is necessary to supply a relatively large catching current and a hold current to the electromagnet so as to obtain an electromagnetic force that overcomes the compression reaction force, and the power consumption of the battery increases.
[0004]
Therefore, the present invention provides a valve operating device for an internal combustion engine that can obtain a buffering effect at the time of armature sitting without increasing the catching current and the holding current of the electromagnet and can save battery power consumption. is there.
[0005]
[Means for Solving the Problems]
According to the first aspect of the present invention, an armature connected to each of the valve shafts of the intake and exhaust valves, two electromagnets disposed opposite to the upper and lower surfaces of the armature, and opening the valve shaft. A valve operating device for an internal combustion engine, comprising: two spring members for biasing the intake side and the valve closing side, wherein the intake and exhaust valves are electromagnetically opened and closed by cooperation of the electromagnet and the spring member. A piston that protrudes and retracts from the suction surface on which the armature is seated in the core of each solenoid valve, a hydraulic oil chamber that stores hydraulic oil at the back of the piston, and a hydraulic oil chamber that is provided in connection with the hydraulic oil chamber and pushes the piston out of the hydraulic oil chamber A shock absorber provided with a resistance passage for providing resistance to the flow of the hydraulic oil flowing out is provided , and the hydraulic oil chamber of the shock absorber provided in the core of each electromagnet is communicated with the resistance passage .
[0007]
According to the second aspect of the present invention, the resistance passage according to the first aspect is provided with an orifice for adjusting a damping force, and the resistance passage is provided with a bypass passage that bypasses the orifice. When the valve train cools, the flow of hydraulic oil to the orifice is shut off to open the bypass passage, and after the valve train warms up, the bypass passage is shut off to activate the orifice. A switching valve that allows oil to flow is provided.
[0008]
In the invention of claim 3, the variable orifice for damping force adjustment for variably controlling the orifice size in response to temperature condition of the valve device resistance path according to claim 1 is provided, at the time of cold of the valve operating device It is characterized in that the orifice diameter is maximized below a corresponding predetermined temperature.
[0009]
According to the fourth aspect of the present invention, an armature connected to each of the intake and exhaust valve shafts, two electromagnets disposed opposite the upper and lower surfaces of the armature, and opening the valve shaft. A valve operating device for an internal combustion engine, comprising: two spring members for biasing the intake side and the valve closing side, wherein the intake and exhaust valves are electromagnetically opened and closed by cooperation of the electromagnet and the spring member. A piston that protrudes and retracts from the suction surface on which the armature is seated in the core of each solenoid valve, a hydraulic oil chamber that stores hydraulic oil at the back of the piston, and a hydraulic oil chamber that is provided in connection with the hydraulic oil chamber and pushes the piston out of the hydraulic oil chamber While providing a shock absorber provided with a resistance passage that provides resistance to the flow of hydraulic oil flowing out, while opening the resistance passage to the outside, a hydraulic oil supply passage is provided in the hydraulic oil chamber, and these resistance passages are provided. On-off valves for each hydraulic oil supply passage By controlling the operation of these on-off valves, the resistance passage is kept open when the valve operating device is cold, while the hydraulic oil supply passage is kept shut off. Opening / closing control in response to the excitation and demagnetization of the hydraulic fluid to supply hydraulic oil from the hydraulic oil supply passage to the hydraulic oil chamber and to buffer the hydraulic oil from flowing out of the hydraulic oil chamber to the resistance passage. It is characterized by.
[0010]
【The invention's effect】
According to the first aspect of the present invention, when the armature abuts on the piston of the shock absorber and pushes the piston by the electromagnetic force of the electromagnet immediately before the armature is seated on the suction surface of the core, the pushing of the piston causes the hydraulic oil to move. Hydraulic oil in the chamber flows into the resistance passage and flows through the resistance passage, thereby generating a flow resistance, braking the armature to reduce a shock at the time of sitting and reducing an impact sound at the time of armature sitting, Sound vibration performance can be improved, and wear of the armature and the core of the electromagnet can be suppressed.
[0011]
In addition, for the pushing operation of the piston of the shock absorber when the armature is seated, the reaction oil increases in proportion to the displacement of the armature only by the hydraulic oil flowing from the hydraulic oil chamber to the resistance passage due to the flow resistance. When the armature sits on the suction surface of the core and the piston stops at a full stroke, the reaction force to the armature disappears, so the catching current and hold current to the electromagnet can be reduced, Battery power consumption can be reduced.
[0012]
Further, since the respective hydraulic oil chambers of the shock absorbers provided in the upper and lower two electromagnets communicate with each other through the resistance passage, when the shock absorber of one of the shock absorbers performs the buffer operation, the operation oil flowing out of the hydraulic oil chamber of the one of the shock absorbers. The oil flows into the hydraulic oil chamber of the other shock absorber, and the other shock absorber is extended and operated to be always in a buffering state. Therefore, the followability at the time of high engine rotation can be enhanced with a simple structure.
[0013]
According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, when the valve gear in which the viscosity of the hydraulic oil increases becomes cold, the shock absorbing operation of the one shock absorber is performed during the cold operation of the one shock absorber. The hydraulic oil flowing out of the hydraulic oil chamber flows into the hydraulic oil chamber of the other shock absorber through the bypass passage bypassing the orifice without passing through the orifice for adjusting the damping force provided in the resistance passage. Increase of the flow resistance due to the increase in viscosity of the valve gear can be suppressed, and the initialization operation at the time of cold operation of the valve train can be performed smoothly, and the battery power consumption at the time of initialization can be reduced. .
[0014]
According to the third aspect of the present invention, in addition to the effect of the first aspect of the invention, when the valve gear is cold in which the viscosity of the hydraulic oil increases, the orifice of the variable orifice for adjusting the damping force provided in the resistance passage is provided. In order to increase the diameter to the maximum, it is possible to suppress an increase in flow resistance due to an increase in the viscosity of the hydraulic oil. Battery power consumption can be saved.
[0015]
Also, after the valve gear is warmed up, the flow resistance of the hydraulic oil can be adjusted by changing the orifice diameter of the variable orifice according to the temperature conditions of the hydraulic oil. A suitable buffer action can be performed without being affected by the above.
[0016]
According to the fourth aspect of the present invention, when the armature abuts on the piston of the shock absorber and pushes the piston by the electromagnetic force of the electromagnet immediately before the armature is seated on the suction surface of the core, the pushing of the piston causes the hydraulic oil to move. Hydraulic oil in the chamber flows into the resistance passage and flows through the resistance passage, thereby generating a flow resistance, braking the armature to reduce a shock at the time of sitting and reducing an impact sound at the time of armature sitting, Sound vibration performance can be improved, and wear of the armature and the core of the electromagnet can be suppressed.
In addition, when the valve gear is cold in which the viscosity of the hydraulic oil increases, the resistance passage is maintained in an open state by controlling the operation of each open / close valve of the externally opened resistance passage and the hydraulic oil supply passage provided in the hydraulic oil chamber. On the other hand, since the hydraulic oil supply passage is maintained in the shut-off state and the hydraulic oil chamber can be kept empty, the reaction force to the armature due to the pushing of the piston can be eliminated, and the valve gear In addition, the initialization operation in the cold state can be smoothly performed, and the power consumption of the battery during the initialization can be reduced.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
[0018]
In FIG. 1, reference numeral 1 denotes a valve body such as an intake valve or an exhaust valve, and 2 denotes a valve operating device of the valve body 1.
[0019]
The valve gear 2 includes an armature 4 made of a magnetic metal material connected to the valve shaft 1a of the valve body 1, and cores 5a, 6a and exciting coils 5b, 6b. Two electromagnets 5 and 6 provided on the valve-opening side and the valve-closing side are provided, and coil springs 7 and 8 as two spring members for urging the valve shaft 1a toward the valve-opening side and the valve-closing side. I have.
[0020]
The coil springs 7 and 8 are set to have a required balanced spring force so that the valve body 1 holds the intermediate lift position when the electromagnets 5 and 6 are demagnetized. The electromagnetic force of the electromagnets 5 and 6 and the spring force of the coil springs 7 and 8 open and close the valve body 1 so that an electromagnetic force of a magnitude corresponding to the magnitude of the spring force is obtained. I have to do it.
[0021]
The armature 4 has an armature shaft 4a fixed at the center of the lower surface thereof, and the lower end of the armature shaft 4a is connected to the contact 4b inserted into the upper end of the valve shaft 1a to be connected to the valve shaft 1a. .
[0022]
The lower end of a spring shaft 9a fixed to the upper movable side spring seat 9 abuts the center of the upper surface of the armature 4, and the coil spring 7 on the valve-opening side is fixed to the fixed side spring seat 10 fixed to the upper wall of the housing 3. It is mounted between the movable spring seat 9 and the movable side.
[0023]
The coil spring 8 on the valve closing side is arranged in a concave portion 11a provided in the cylinder head 11, and includes a movable spring seat 12 fixed on the valve shaft 1a and a fixed spring seat 13 fixed on the bottom surface of the concave portion 11a. It is loaded in between.
[0024]
The electromagnets 5 and 6 on the valve-opening side and the valve-closing side are provided with shock absorbers 20 and 21 for reducing an impact when the armature 4 is seated.
[0025]
As shown in FIG. 2, these shock absorbers 20 and 21 are provided on the cores 5a and 6a of the electromagnets 5 and 6 and protrude and retract from their armature attracting surfaces. Hydraulic oil chambers 24 and 25 storing the hydraulic oil, and a resistance to the flow of the hydraulic oil flowing out of the hydraulic oil chambers 24 and 25 when the pistons 22 and 23 are pushed by being provided with the hydraulic oil chambers 24 and 25. In the present embodiment, the two working oil chambers 24 and 25 communicate with each other through the resistance passage 26.
[0026]
The resistance passage 26 is provided with an orifice 27 for adjusting a damping force, and is connected to a hydraulic oil supply passage 28 having a check valve 29 so that hydraulic oil can be supplied from the hydraulic oil supply passage 28. .
[0027]
In FIG. 1, reference numeral 14 denotes a valve seat.
[0028]
According to the structure of the above embodiment, a catching current for attracting the armature 4 and the armature 4 are seated and held by the exciting coil 5b of the valve-opening electromagnet 5 and the exciting coil 6b of the valve-closing electromagnet 6. Are alternately supplied, and the valve body 1 is opened and closed by alternately repeating the suction and seating of the armature 4 on the suction surface of the core 5a and the suction and seating of the core 6a on the suction surface. You.
[0029]
Here, when the armature 4 is seated on the cores 5a, 6a, for example, immediately before the armature 4 is seated on the core 6a of the valve-closing electromagnet 6 as shown in FIG. When the piston 23 is pressed against the armature, the hydraulic oil in the hydraulic oil chamber 25 flows out to the resistance passage 26 due to the pushing of the piston 23 and flows through the resistance passage 26 to generate a flow resistance. Braking 4
[0030]
As a result, the impact when the armature 4 is seated on the core 6a is reduced, and the impact sound at the time of seating is reduced.
[0031]
Similarly, when the valve-opening electromagnet 5 of the armature 4 is seated on the core 5a, the hydraulic oil flows out of the hydraulic oil chamber 24 to the resistance passage 26 by the pushing of the piston 22 of the shock absorber 20, thereby generating a flow resistance. As a result, the armature 4 is braked to reduce the impact noise when the armature 4 is seated on the core 6a, thereby reducing the contact noise. Therefore, the suction of the armature 4 to the cores 5a and 6a and the sound vibration performance when seated are improved. And wear of the armature 4 and the cores 5a and 6a of the electromagnets 5 and 6 can be suppressed.
[0032]
When the armature 4 is seated on the cores 5a, 6a, the pistons 22 and 23 of the shock absorbers 20 and 21 are pushed by the hydraulic oil from the hydraulic oil chambers 24 and 25 to the resistance passage 26 due to the flow resistance. When the armature 4 is seated on the suction surfaces of the cores 5a and 6a and the pistons 22 and 23 are full-stroke and stop, the armature 4 does not increase in reaction force proportional to the displacement of the armature 4. Since the reaction force to the armature 4 disappears, the catching current and the holding current to the electromagnets 5 and 6 can be reduced, and the power consumption of the battery can be reduced.
[0033]
In this embodiment, since the hydraulic oil chambers 24 and 25 of the upper and lower shock absorbers 20 and 21 are communicated with each other through the resistance passage 26 in the present embodiment, when one of the shock absorbers 21 is in a shock-absorbing operation, the other of the shock absorbers 21 is not operated. The operating oil flowing out of the operating oil chamber 25 flows into the operating oil chamber 24 of the other shock absorber 20, and the other shock absorber 20 is extended (the piston 22 advances) to be always in a buffering state. With such a simple structure, it is possible to enhance the followability at the time of high engine speed.
[0034]
FIG. 3 shows a second embodiment of the present invention. In this embodiment, a bypass passage 30 for bypassing an orifice 27 for adjusting a damping force is provided in the resistance passage 26 in the first embodiment shown in FIG. And a three-way solenoid valve 31 as a switching valve for switching the flow path of hydraulic oil between the orifice 27 and the bypass passage 30 at one of the connecting portions of the bypass passage 30 and the resistance passage 26. is there.
[0035]
The operation of the three-way solenoid valve 31 is controlled by an engine control unit based on, for example, a detection signal of an oil temperature sensor for detecting the temperature of hydraulic oil in a cylinder head oil gallery (not shown). When the temperature is equal to or lower than the predetermined temperature, the flow of the hydraulic oil to the orifice 27 is cut off to open the bypass passage 30, and when the temperature of the hydraulic oil exceeds the predetermined temperature and rises to a temperature corresponding to the completion of the warm-up of the valve gear 2, The switching operation is performed such that the bypass passage 30 is shut off and the flow of the hydraulic oil to the orifice 27 is permitted.
[0036]
Therefore, according to the structure of the second embodiment, when the valve train 2 is in the warm-up completed state, the bypass passage 30 is shut off by the three-way solenoid valve 31 and the flow of the hydraulic oil to the orifice 27 is allowed. Therefore, the same operation and effect as those of the first embodiment can be obtained.
[0037]
On the other hand, when the valve gear 2 is cold when the viscosity of the hydraulic oil increases, the three-way solenoid valve 31 opens the bypass passage 30 to cut off the flow of the hydraulic oil to the orifice 27. During the shock absorbing operation, the operating oil flowing out of the operating oil chamber 25 of the one shock absorber 21 does not pass through the orifice 27 of the resistance passage 26 but passes through the bypass passage 30 bypassing the orifice 27 to operate the other shock absorber 20. Since the fluid flows into the oil chamber 24, an increase in flow resistance due to an increase in the viscosity of the hydraulic oil can be suppressed.
[0038]
Therefore, it is possible to smoothly perform the initialization operation of the valve train 2 at the time of cold operation, and it is possible to reduce the power consumption of the battery at the time of initialization.
[0039]
FIG. 4 shows a third embodiment of the present invention. In this embodiment, instead of the orifice 27 of the resistance passage 26 in the first embodiment shown in FIG. The variable orifice 32 for variably controlling the orifice diameter according to the above is provided so that the damping force can be adjusted.
[0040]
The variable orifice 32 includes, for example, a temperature sensing part 33 in which a thermowax 34 is enclosed. The temperature sensing part 33 senses the operating oil temperature to change the orifice diameter by the expansion and contraction action of the thermowax 34, and the valve actuation is performed. When the temperature of the device 2 is equal to or lower than a predetermined temperature corresponding to the time of cooling, the diameter of the orifice is increased to a maximum, for example, approximately equal to the inner diameter of the resistance passage 26.
[0041]
Therefore, according to the structure of the third embodiment, at the time of cooling of the valve train 2 in which the viscosity of the hydraulic oil increases, the orifice diameter of the variable orifice 32 provided in the resistance passage 26 is substantially equal to the inner diameter of the resistance passage 26. As in the second embodiment, it is possible to suppress an increase in the flow resistance due to an increase in the viscosity of the hydraulic oil, and to smoothly perform the initialization operation of the valve train 2 during cold operation. At the same time, battery power consumption at the time of initialization can be reduced.
[0042]
On the other hand, after the valve gear 2 is completely warmed up, the flow resistance of the hydraulic oil can be adjusted by changing the orifice diameter of the variable orifice 32 according to the temperature condition of the hydraulic oil. An appropriate buffer action can be performed without being affected by a change in viscosity.
[0043]
FIG. 5 shows a fourth embodiment of the present invention. In FIG. 5, the shock absorber 21 provided on the core 6a of the valve-closing electromagnet 6 is schematically shown for convenience. The shock absorber 20 on the electromagnet 5 side has the same structure as the structure described below.
[0044]
That is, the resistance passage 26 connected to the hydraulic oil chamber 25 is provided with an orifice 27 for adjusting the damping force. The resistance passage 26 is open to an external oil reservoir or the like. The hydraulic oil supply passage 28 is provided to supply hydraulic oil to the hydraulic oil chamber 25 from the hydraulic oil supply passage 28.
[0045]
The resistance passage 26 and the hydraulic oil supply passage 28 are provided with on-off valves 35 and 36 that are opened and closed by the engine control unit described above.
[0046]
The on-off valve 35 provided in the resistance passage 26 is opened when the engine is stopped, and the valve-opening state is maintained when the valve operating device 2 is cold. And the valve is opened almost simultaneously with the excitation of the exciting coil 6b.
[0047]
On the other hand, the on-off valve 36 provided in the hydraulic oil supply passage 28 is closed when the engine stops, and the closed state is maintained when the valve train 2 is cold, but if the valve train 2 is in the warm-up completed state. The valve is opened almost simultaneously with the demagnetization of the exciting coil 6b to supply hydraulic oil of a predetermined pressure to the hydraulic oil chamber 25 to extend the piston 23, and the resistance which is shut off by the hydraulic oil chamber 25 and the on-off valve 35. The passage 26 is filled with hydraulic oil, and the valve is closed almost simultaneously with the excitation of the excitation coil 6b.
[0048]
Therefore, according to the structure of the fourth embodiment, the on-off valve 35 provided on the resistance passage 26 and the on-off valve 36 provided on the hydraulic oil supply passage 28 excite the electromagnet 6 when the valve train 2 has been completely warmed up. The opening and closing operations are repeated in response to the excitation and demagnetization of the coil 6a to supply the hydraulic oil from the hydraulic oil supply passage 28 to the hydraulic oil chamber 25, and to buffer the hydraulic oil from the hydraulic oil chamber 25 to the resistance passage 26 by the hydraulic oil flowing out. As a result, the sound vibration performance when the armature is seated can be improved without increasing the catching current and the hold current as in the first embodiment.
[0049]
When the engine is stopped, the on-off valve 36 is closed to shut off the hydraulic oil supply passage 28, while the on-off valve 35 is opened to open the resistance passage 26. When the temperature of the hydraulic oil inside is high and the viscosity is low, the hydraulic oil in the hydraulic oil chamber 25 can be made to flow out of the resistance passage 26 to the outside, and the hydraulic oil chamber 25 can be emptied.
[0050]
Therefore, when the valve gear 2 is initialized before the engine is started at the time of cooling of the valve gear 2 in which the viscosity of the hydraulic oil increases, the on-off valve 35 keeps the resistance passage 26 open. Since the hydraulic oil supply passage 28 is kept closed and the hydraulic oil chamber 25 can be kept empty, the reaction force to the armature 4 due to the pushing of the piston 23 can be eliminated, and The initialization operation when the valve device 2 is cold can be performed smoothly, and the power consumption of the battery at the time of initialization can be reduced.
[Brief description of the drawings]
FIG. 1 is a schematic sectional explanatory view showing an embodiment of the present invention.
FIG. 2 is a schematic sectional explanatory view showing a main part of the embodiment.
FIG. 3 is a schematic sectional explanatory view showing a main part of a second embodiment of the present invention.
FIG. 4 is a schematic sectional explanatory view showing a main part of a third embodiment of the present invention.
FIG. 5 is a schematic explanatory view showing a shock absorber according to a fourth embodiment of the present invention.
[Explanation of symbols]
1 Valve body (intake and exhaust valves)
1a Valve shaft 2 Valve train 4 Armature 5 Valve opening side electromagnet 5a Core 5b Exciting coil 6 Valve closing side electromagnet 6a Core 6b Exciting coil 7 Valve opening side spring member 8 Valve closing side spring member 20, 21 Shock absorber 22, 23 Piston 24, 25 Hydraulic oil chamber 26 Resistance passage 27 Orifice 28 Hydraulic oil supply passage 30 Bypass passage 31 Switching valve 32 Variable orifice 35, 36 On-off valve

Claims

Armatures connected to the respective valve shafts of the intake and exhaust valves, two electromagnets disposed opposite to the upper and lower surfaces of the armature, and biases the valve shafts toward the valve opening side and the valve closing side. In a valve operating device for an internal combustion engine, comprising two spring members, wherein intake and exhaust valves are electromagnetically opened and closed by cooperation of these electromagnets and spring members, an armature is seated on a core of each of the electromagnetic valves. Piston that protrudes and retracts from the adsorbing surface, a hydraulic oil chamber that stores hydraulic oil at the back of the piston, and resistance provided to the flow of hydraulic oil flowing out of the hydraulic oil chamber when the piston is pushed and provided with the hydraulic oil chamber. A valve train for an internal combustion engine, wherein a hydraulic oil chamber of a shock absorber provided in a core of each electromagnet is communicated by a resistance passage while providing a shock absorber having a resistance passage .

An orifice for damping force adjustment is provided in the resistance passage, and a bypass passage for bypassing the orifice is provided in the resistance passage. One of the connecting portions between the bypass passage and the resistance passage is connected to the orifice when the valve operating device is cold. And a switching valve for shutting off the bypass passage and opening the bypass passage to allow the passage of the hydraulic oil to the orifice after warming-up of the valve train is completed. The valve train for an internal combustion engine according to claim 1 .

A variable orifice for adjusting the damping force, which variably controls the diameter of the orifice according to the temperature condition of the valve train, is provided in the resistance passage so that the orifice diameter is expanded to a maximum below a predetermined temperature corresponding to when the valve train is cold. The valve train for an internal combustion engine according to claim 1 , wherein:

Armatures connected to the respective valve shafts of the intake and exhaust valves, two electromagnets disposed opposite to the upper and lower surfaces of the armature, and biases the valve shafts toward the valve opening side and the valve closing side. In a valve operating device for an internal combustion engine, comprising two spring members, wherein intake and exhaust valves are electromagnetically opened and closed by cooperation of these electromagnets and spring members, an armature is seated on a core of each of the electromagnetic valves. Piston that protrudes and retracts from the adsorbing surface, a hydraulic oil chamber that stores hydraulic oil at the back of the piston, and resistance provided to the flow of hydraulic oil flowing out of the hydraulic oil chamber when the piston is pushed and provided with the hydraulic oil chamber. A resistance passage, and a shock absorber provided with the same, while opening the resistance passage to the outside, a hydraulic oil supply passage is provided in the hydraulic oil chamber, and an opening / closing valve is provided in each of the resistance passage and the hydraulic oil supply passage. , These on-off valves While the valve gear is cold, the resistance passage is kept open when the valve gear is cold, while the hydraulic oil supply passage is kept closed.After the valve gear is warmed up, these on-off valves are opened according to the excitation and demagnetization of the electromagnet. A dynamic operation of the internal combustion engine , wherein the closing control is performed to supply hydraulic oil from the hydraulic oil supply passage to the hydraulic oil chamber and to perform a buffering action due to hydraulic oil flowing out from the hydraulic oil chamber to the resistance passage. Valve device.