JP4076399B2

JP4076399B2 - Valve timing control device for internal combustion engine

Info

Publication number: JP4076399B2
Application number: JP2002247985A
Authority: JP
Inventors: 克成吉田; 正彦渡辺
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 2002-08-28
Filing date: 2002-08-28
Publication date: 2008-04-16
Anticipated expiration: 2022-08-28
Also published as: JP2004084588A

Description

【０００１】
【発明の属する技術分野】
この出願の発明は、内燃機関の吸気側または排気側の機関弁の開閉タイミングを運転状態に応じて可変制御する内燃機関のバルブタイミング制御装置に関する。
【０００２】
【従来の技術】
この種のバルブタイミング制御装置として、特開２００１−４１０１３号公報に記載されるようなものがある。
【０００３】
この装置は、クランクシャフトにタイミングチェーン等を介して連係されたハウジング（駆動回転体）がカムシャフトの端部に回動可能に組み付けられ、ハウジングの内側端面に形成された径方向ガイドに可動案内部が径方向に沿って摺動自在に係合支持されると共に、径方向外側に突出するレバーを有するレバー軸（従動回転体）がカムシャフトの端部にボルト結合され、可動案内部とレバー軸のレバーとがリンクによって枢支連結されている。そして、前記径方向ガイドに対向する位置には、渦巻き状ガイドを有する中間回転体がハウジングとレバー軸に対して相対回動可能に設けられ、前記可動案内部の軸方向の一方の端部に突設された略円弧状の複数の突条が前記渦巻き状ガイドに案内係合されている。また、中間回転体はハウジングに対して回転を進める側にゼンマイばねによって付勢されると共に、電磁ブレーキによって回転を遅らせる側の力を適宜受けるようになっている。
【０００４】
この装置の場合、電磁ブレーキがＯＦＦ状態のときには、中間回転体がゼンマイばねの付勢力を受けハウジングに対して初期位置に位置されており、渦巻き状ガイドに突条でもって噛合う可動案内部は径方向外側に最大に変位し、リンクを引き起こしてハウジングとカムシャフトの組付角を最遅角位置または最進角位置に維持している。そして、この状態から電磁ブレーキがＯＮにされると、中間回転体が減速されてハウジングに対して遅れ側に相対回転する結果、渦巻き状ガイドに噛合う可動案内部が径方向内側に変位し、今まで引き起こされていたリンクを次第に倒すようにしてハウジングとカムシャフトの組付角を最進角位置または最遅角位置に変更する。
【０００５】
尚、電磁ブレーキは、電磁コイルと磁気誘導部材から成る制動力発生部がＶＴＣカバー等の非回転部材に固定され、磁気誘導部材の端面に対峙する中間回転体が制動力を直接受ける制動力受部となっている。
【０００６】
【発明が解決しようとする課題】
しかし、上記従来のバルブタイミング制御装置の場合、電磁ブレーキの制動力発生部（磁気誘導部材）と、制動力受部（中間回転体）の位置関係が相互に何等拘束されていないため、機関運転に伴なってカムシャフトの先端部が曲げ方向や回転方向に変動すると、その変動によって制動力発生部と制動力受部の間の間隔や対峙姿勢が変化し、所望の制動力が得られなくなる可能性がある。
【０００７】
そこでこの出願の発明は、カムシャフトの先端部の変動に拘らず、制動力発生部と制動力受部の間の間隔や対峙姿勢を一定に維持できるようにして、常に安定した操作性能を得ることのできる内燃機関のバルブタイミング制御装置を提供しようとするものである。
【０００８】
【課題を解決するための手段】
上述した課題を解決するための手段として、本願請求項１に係る発明は、電磁ブレーキの制動力発生部を非回転部材に固定すると共に、前記電磁ブレーキの制動力受部を、前記カムシャフトや従動回転体に対して離間状態に配置しかつ前記制動力発生部に軸受を介して相対回転自在に支持させ、前記制動力受部を、組付角操作機構の中間回転体に所定の遊びをもたせて連係させるようにした。
【０００９】
この発明の場合、制動力受部は制動力発生部に軸受を介して支持されているため、外力の入力に拘らず両者の間隔は一定に維持される。また、制動力受部と中間回転体は所定の遊びを持たせて連係されているため、両者が所定距離以上に相対移動しない範囲では両者間に大きな荷重が伝達されない。このため、カムシャフトの変動は中間回転体から制動力受部に入力されにくくなる。したがって、これらのことから、制動力発生部と制動力受部の間の間隔や対峙姿勢を常に一定に維持することが可能となり、その結果、バルブタイミング制御装置の操作性が安定する。
【００１０】
制動力受部と中間回転体は弾性体を介して連結することが望ましい。この場合、制動力受部と中間回転体の連結部において、弾性体によってカムシャフトの先端部の変動を吸収できるため、制動力受部と中間回転体の間の荷重伝達時のガタ付きや衝撃の発生を無くすことが可能となる。
【００１１】
制動力発生部は、略円筒状の隙間を挟んで対向する一対の周面状の対向面を有する磁気誘導部材と、前記一対の対向面のうちの径方向内側の面に、複数の極歯要素が円周方向に沿って設けられた内側極歯と、前記一対の対向面のうちの径方向外側の面に、複数の極歯要素が円周方向に沿って設けられ、各極歯要素が前記内側極歯の極歯要素に対して円周方向にオフセットして配置された外側極歯と、内側極歯と外側極歯の間に磁界を生じさせる電磁コイルと、を備えた構成とし、前記制動力受部は、前記内側極歯と外側極歯の間の隙間に挿入される円筒壁を有するヒステリシス材を備えた構成としても良い。
【００１２】
ヒステリシス材の磁気的ヒステリシス特性を利用するこのような電磁ブレーキにおいては、各極歯とヒステリシス材の間隔を狭めるほど大きな制動力が得られるため、両者の間隔はできる限り狭めることが望ましい。しかし、各極歯とヒステリシス材の間隔を狭めていくと、ヒステリシス材が両極歯に対して変動したときに、ヒステリシス材が極歯に接触し、それによってブレーキ制御が不安定になるばかりでなく、接触部相互の摩耗や損傷を招き易くなる。このバルブタイミング制御装置で用いるブレーキにおいては、制動力受部であるヒステリシス材と制動力発生部の極歯の間隔が軸受によって一定に維持され、しかも、中間回転体と制動力受部の間のガタ付きが両者間の遊びによって吸収されるため、ヒステリシス材と極歯の接触を招くことなく両者の間隔を充分に狭め、大きな制動力を得ることが可能となる。
【００１３】
【発明の実施の形態】
次に、この出願の発明の一実施形態を図面に基づいて説明する。
【００１４】
この実施形態は、この出願の発明にかかるバルブタイミング制御装置を内燃機関の吸気側の動力伝達系に適用したものであるが、排気側の動力伝達系に同様に適用することも可能である。
【００１５】
バルブタイミング制御装置は、図１に示すように内燃機関のシリンダヘッド（図示せず）に回転自在に支持されたカムシャフト１と、このカムシャフト１の前端部に必要に応じて相対回動できるように組み付けられ、チェーン（図示せず）を介してクランクシャフト（図示せず）に連係されるタイミングスプロケット２を外周に有する駆動リング３（駆動回転体）と、この駆動リング３とカムシャフト１の前方側（図１中左側）に配置されて、両者３，１の組付角を操作する組付角操作機構４と、この組付角操作機構４のさらに前方側に配置されて、同機構４を駆動する操作力付与手段５と、内燃機関の図外のシリンダヘッドとヘッドカバーの前面に跨って取り付けられて組付角操作機構４と操作力付与手段５の前面と周域を覆う図外のＶＴＣカバーと、を備えている。
【００１６】
駆動リング３は、段差状の挿通孔６を備えた略円板状に形成され、この挿通孔６部分が、カムシャフト１の前端部に結合された従動軸部材７（従動回転体）に回転可能に組み付けられている。そして、駆動リング３の前面（カムシャフト１と逆側の面）には、図２に示すように、対面する平行な側壁を有する３つの径方向溝８（径方向ガイド）が同リング３のほぼ半径方向に沿うように形成されている。
【００１７】
また、従動軸部材７は、図１に示すように、カムシャフト１の前端部に突き合される基部側外周に拡径部が形成されると共に、その拡径部よりも前方側の外周面に放射状に突出する三つのレバー９が一体に形成され、軸芯部を貫通するボルト１０によってカムシャフト１に結合されている。各レバー９には、リンク１１の基端がピン１２によって枢支連結され、各リンク１１の先端には前記各径方向溝８に摺動自在に係合する円柱状の突出部１３が一体に形成されている。
【００１８】
各リンク１１は、突出部１３が対応する径方向溝８に係合した状態において、ピン１２を介して従動軸部材７に連結されているため、リンク１１の先端側が外力を受けて径方向溝８に沿って変位すると、駆動リング３と従動軸部材７はリンク１１の作用でもって突出部１３の変位に応じた方向及び角度だけ相対回動する。
【００１９】
また、各リンク１１の先端部には、軸方向前方側に開口する収容穴１４が形成され、この収容穴１４に、後述する渦巻き溝１５（渦巻き状ガイド）に係合する係合ピン１６と、この係合ピン１６を前方側（渦巻き溝１５側）に付勢するコイルばね１７とが収容されている。尚、この実施形態の場合、リンク１１の先端の突出部１３と係合ピン１６、コイルばね１７等によって径方向に変位可能な可動案内部が構成されている。
【００２０】
一方、従動軸部材７のレバー９の突設位置よりも前方側には、円板状のフランジ壁を有する中間回転体１８が軸受１９を介して回転自在に支持されている。この中間回転体１８のフランジ壁の後面側には断面半円状の前述の渦巻き溝１５が形成され、この渦巻き溝１５に、前記各リンク１１の先端の係合ピン１６が転動自在に案内係合されている。渦巻き溝１５の渦巻きは、機関回転方向Ｒに沿って次第に縮径するように形成されている。したがって、各リンク１１先端の係合ピン１６が渦巻き溝１５に係合した状態において、中間回転体１８が駆動リング３に対して遅れ方向に相対回転すると、リンク１１の先端部は径方向溝８に案内されつつ、渦巻き溝１５の渦巻き形状に誘導されて半径方向内側に移動し、逆に、中間回転体１８が進み方向に相対変位すると、半径方向外側に移動する。
【００２１】
尚、図中４８，４９は、駆動リング３と中間回転体１８が設定角度以上に相対回動したときに当接して両者３，１８の回動を規制する突起とストッパである。
【００２２】
組付角操作機構４は、以上説明した駆動リング３の径方向溝８、リンク１１、突出部１３、係合ピン１６、レバー９、中間回転体１８、渦巻き溝１５等によって構成されている。この組付角操作機構４は、操作力付与手段５から中間回転体１８にカムシャフト１に対する相対的な回動操作力が入力されると、その操作力が渦巻き溝１５と係合ピン１６の係合部を通してリンク１１の先端を径方向に変位させ、このときリンク１１とレバー９の作用でもって駆動リング３と従動軸部材７に相対的な回動力を伝達する。
【００２３】
一方、操作力付与手段５は、中間回転体１８を駆動リング３に対して機関回転方向Ｒに付勢するゼンマイばね４７と、中間回転体１８を駆動リング３に対して機関回転方向Ｒと逆方向に付勢すべく制動機構であるヒステリシスブレーキ２０（電磁ブレーキ）と、を備えて成り、内燃機関の運転状態に応じてヒステリシスブケーキ２０の制動力を適宜制御することにより、中間回転体１８を駆動リング３に対して相対回動させ、或は、両者の回転位置を維持するようになっている。
【００２４】
ゼンマイばね４７は、駆動リング３に延設された円筒壁２１にその外周端部が結合される一方、内周端部が中間回転体１８の円筒状の基部に結合され、全体が中間回転体１８のフランジ壁の前方側スペースに配置されている。また、中間回転体１８のカムシャフト１と逆側の端面には、封止壁５０が一体に結合され、その封止壁５０の外周面が前記円筒壁２１の内面に摺動自在に密接している。中間回転体１８には、先端部がカムシャフト１と逆側方向に突出する一対の連結ピン５３が封止壁５０を貫通して取り付けられている。この連結ピン５３については後述する。
【００２５】
一方、ヒステリシスブレーキ２０は、非回転部材であるＶＴＣカバーに取り付けられ、略円筒状の隙間を挟んで対向する一対の周面状の対向面を有する磁気誘導部材２２と、前記両対向面に夫々設けられた内側極歯２３、及び、外側極歯２４と、磁気誘導部材２２に取り付けられて内側極歯２３と外側極歯２４の間に磁界を生じさせる電磁コイル２５と、前記中間回転体１８に連結された状態で前記両極歯２３，２４間に挿入配置された円筒状のヒステリシスリング２６と、を備え、電磁コイル２５が図外のコントローラによって通電制御されるようになっている。
【００２６】
この実施形態の場合、ヒステリシスブレーキ２０は図１，図４に示すようにユニット化されている。
【００２７】
磁気誘導部材２２は、外周面に内側極歯２３を有する内歯リング２７と、内周面に外側極歯２４を有する外歯リング２８と、内歯リング２７と外歯リング２８を連結する連結リング２９とから構成されている。そして、連結リング２９の極歯２３，２４に臨む側の外周コーナ部分には環状の段部が設けられ、その段部に前記電磁コイル２５が嵌合装着されている。
【００２８】
また、前記内側極歯２３と外側極歯２４は夫々軸方向に沿って延出する複数の極歯要素を有している。両極歯２３，２４の極歯要素は夫々円周方向に沿って配置され、極歯２３，２４の極歯要素相互は円周方向に相互にオフセットされている。したがって、電磁コイル２５が通電されると、両極歯２３，２４間には、オフセットした位置関係にある相手極歯要素に向かう磁界が発生する。
【００２９】
また、電磁コイル２５の通電のためのハーネス２５ａは、磁気誘導部材２２（外歯リング２８）を径方向外側に貫通し、磁気誘導部材２２の外周面側から外部に引き出されている。磁気誘導部材２２内の磁路断面積は径方向外側ほど大きく確保できるため、この実施形態のようにハーネス引き出し部を磁気誘導部材２２を径方向外側に貫通するように設けた場合には、ハーネス引出し部を設けたことによる磁路断面積の損失の影響は少なくなる。
【００３０】
一方、ヒステリシスリング２０は、磁気的ヒステリシス特性を有するヒステリシス材から成り、前記両極歯２３，２４の隙間から突出したその端部には、金属製の円環プレート３３（プレート部材）が嵌着固定されている。この円環プレート３３は、前記連結リング２９の内周面に軸受３４，３５を介して支持されたステンレス製の軸部材３６に一体に結合されている。したがって、ヒステリシスリング２０は、円環プレート３３と軸部材３６を介して磁気誘導部材２２に相対回転可能に支持されている。尚、軸部材３６は非磁性体であるステンレスによって形成されているため、電磁コイル２５の磁束が軸部材３６を通過することによって軸部材３６に異物が吸着する不具合は生じない。
【００３１】
また、円環プレート３３の裏面（カムシャフト１側の面）には、一対の円形状の凹部３７が設けられ、その各凹部３７にゴムブッシュ３８（弾性体）を介して中間回転体１８側の連結ピン５３が嵌合されている。したがって、円環プレート３３及びヒステリシスリング２０は、ゴムブッシュ３８と連結ピン５３を介して中間回転体１８と一体に回転する。尚、ゴムブッシュ３８は弾性を有し、連結ピン５３と凹部３７の間の若干の相対変位を許容するため、円環プレート３３と中間回転体１８は所定の遊びをもって連係されているものと言える。また、円環プレート３３の裏面の外周縁部には円環状の肉抜き溝３１（肉抜き部）が設けられ、その肉抜き溝３１によって回転アンバランスを招くことなく円環プレート３３の軽量化が図られている。
【００３２】
この実施形態の場合、ゴムブッシュ３８はほぼ一定肉厚の円筒状に形成され、連結ピン５３の外周面に予め加硫接着されている。そして、各連結ピン５３の先端部のゴムブッシュ３８は、ヒステリシスブレーキ２０の設置時に円環プレート３３の凹部３７内に圧入嵌合される。
【００３３】
ここで、前記円環プレート３３は、図１，図４に示すように、軸受３４，３５とスペーサ４０と共に軸部材３６の頭部３６ａとナット４１の間に挟み込まれることにより、磁気誘導部材２２に対して位置固定されているが、磁気誘導部材２２の円環プレート３３側の端面には、内側極歯２３よりも径方向内側位置から軸方向に窪む凹部３０が設けられ、円環プレート３３の径方向内側領域がこの凹部３０内に突出している。そして、円環プレート３３のうちの、前記連結ピン５３が係合される凹部３７や、軸部材３６の頭部３６ａの座面は凹部３０側に突出した部分に偏寄して配置されている。したがって、磁気誘導部材２２と環状プレート３３の組付時における軸方向長さは磁気誘導部材２２に凹部３０を設けたことによって短縮されている。
【００３４】
また、磁気誘導部材２２に対する円環プレート３３の組付けについてさらに詳しく説明すると、最初に、環状プレート３３側の軸受３４を、磁気誘導部材２２（連結リング２９）の中心孔に、その孔内の軸方向略中央の突起３２に当接するまで挿入し、軸受３４がその突起３２に突き当たったところで、軸受３４のアウタレースを磁気誘導部材２２の円環プレート３３側の孔縁にかしめ固定する。次に、円環プレート３３を挿入係合した軸部材３６をその先端部側から軸受３４のインナレースに圧入する。これにより、軸部材３６が軸受３４を介して磁気誘導部材２２に係止され、円環プレート３３もこのとき同時に係止される。この後、中心孔の反対側から軸部材３６にスペーサ４０を嵌挿し、これにつづいて、インナレースがスペーサ４０に突き当たるまで他方の軸受３５を軸部材３６に圧入し、この状態のまま軸部材３６の先端部にナット４１を螺着する。各軸受３４，３５のインナレースと円環プレート３３は、このナット４１の締め込みによって相互に固定される。ただし、磁気誘導部材２２の内周の突起３２の軸方向長さは、スペーサ４０の軸方向長さよりも短く設定され、ナット４１を締め込んでいった場合であっても、軸受３５のアウタレースが過剰な力で突起に押付けられないようになっている。
【００３５】
尚、この実施形態の場合、ヒステリシスブレーキ２０の制動力発生部は、極歯２３，２４を含む磁気誘導部材２２と、電磁コイル２５によって構成され、制動力受部は、ヒステリシスリング２６と円環プレート３３によって構成されている。
【００３６】
このバルブタイミング制御装置は以上のような構成であるため、内燃機関の始動時やアイドル運転時には、ヒステリシスブレーキ２０の電磁コイル２５の励磁をオフにしておくことにより、ゼンマイばね４７の力によって中間回転体１８を駆動リング３に対して機関回転方向Ｒに最大に回転させておく（図２参照）。これにより、クランクシャフトとカムシャフト１の回転位相（機関弁の開閉タイミング）は最遅角側に維持され、機関回転の安定化と燃費の向上が図られる。
【００３７】
そして、この状態から機関の運転が通常運転に移行し、前記回転位相を最進角側に変更すべき指令が図外のコントローラから発されると、ヒステリシスブレーキ２０の電磁コイル２５の励磁がオンにされ、ゼンマイばね４７に抗する制動力が円環プレート３３から中間回転体１８にゴムブッシュ３８と連結ピン５３を介して伝達される。これにより、中間回転体１８が駆動リング３に対して逆方向に回転し、それによってリンク１１の先端の係合ピン１６が渦巻き溝１５に誘導されてリンク１１の先端部が径方向溝８に沿って変位し、図３に示すようにリンク１１の作用によって駆動リング３と従動軸部材７の組付角が最進角側に変更される。この結果、クランクシャフトとカムシャフト１の回転位相が最進角側に変更され、それによって機関の高出力化が図られることとなる。
【００３８】
また、この状態から前記回転位相を最遅角側に変更すべく指令がコントローラから発されると、ヒステリシスブレーキ２０の電磁コイル２５の励磁がオフにされ、再度ゼンマイばね４７の力によって中間回転体１８が機関回転方向Ｒに回転させられる。すると、渦巻き溝１５による係合ピン１６の誘導によってリンク１１が上記と逆方向に揺動し、図２に示すようにそのリンク１１の作用によって駆動リング３の従動軸部材７の組付角が再度遅角側に変更される。
【００３９】
尚、このバルブタイミング制御装置によるクランクシャフトとカムシャフト１の回転位相は、以上で説明した最遅角と最進角の二種の位相ばかりでなく、ヒステリシスブレーキ２０の制動力の制御によって任意の位相に変更し、ゼンマイばね４７の力とヒステリシスブレーキ２０の制動力のバランスによってその位相を保持することができる。
【００４０】
ところで、このバルブタイミング制御装置は、ヒステリシスブレーキ２０の制動力受部側の円環プレート３３が、制動力発生部側の磁気誘導部材２２に軸受３４，３５を介して支持され、かつ、円環プレート３３と中間回転体１８がゴムブッシュ３８を介して所定の遊び代をもって連係されているため、機関運転中に、中間回転体１８がカムシャフト１と一体に曲げ方向や回転方向に変動することがあっても、その変動によって円環プレート３３がガタ付く不具合は生じない。したがって、円環プレート３３と一体化されたヒステリシスリング２６は、内側極歯２３と外側極歯２４に対して常に一定の間隔と姿勢を維持される。よって、ヒステリシスブレーキ２０は、大きな制動力を確保するためにヒステリシスリング２６と極歯２３，２４の間のギャップを充分に狭めても、安定した制動性能を発揮することが可能となり、バルブタイミング制御装置は、これにより操作性能が確実に向上する。
【００４１】
また、この実施形態のバルブタイミング制御装置の場合、中間回転体１８に突設した連結ピン５３の先端部と円環プレート３３の凹部３７の間にゴムブッシュ３８を介装しているため、カムシャフト１と一体の中間回転体１８の変動をこのゴムブッシュ３８部分で許容することができると共に、連結ピン５３と凹部３７の相対変位に伴うガタ付き音や衝撃の発生をゴムブッシュ３８の弾性によって防止することができる。
【００４２】
尚、ヒステリシスブレーキ２０のヒステリシス材（ヒステリシスリング２６）は、この実施形態の場合、全体を円筒形状に形成して、別部材の円環プレート３３を介して中間回転体１８に連結したが、極歯２３，２４間に非接触状態で介装される円筒壁を有するものであれば、全体を有底円筒形状その他の形状に形成するようにしても良い。ただし、この実施形態のようにヒステリシス材を円筒形状に形成してその端部に別体のプレート部材（円環プレート３３）を取り付けるようにした場合には、中間回転体１８との連結部を材料コストが安く、造形の容易な材料によって形成できるため、製品全体の製造コストの削減を図ることができる。
【００４３】
また、連結ピン５３の先端部は、図７，図８に示すような他の形態を採用することも可能である。
【００４４】
図７は、ゴムブッシュ１３８の軸方向両端側の外周面に、金属等の高硬度材料から成る円筒状の当接部材４５を加硫接着し、この当接部材４５の外周面を円環プレート３３の凹部３７に圧入するようにしたものである。この場合、高硬度の当接部材４５部分で凹部３７に当接するため、ゴムブッシュ１３８を凹部３７に圧入することに伴なう同ブッシュ１３８のいびつな変形や、経時使用によるゴムブッシュ１３８の外周面の摩耗を防止することができると共に、凹部３７からのゴムブッシュ１３８の脱落を防止することができる。
【００４５】
また、図８は、ゴムブッシュ２３８の全体形状を樽形に形成したものである。この場合、ゴムブッシュ２３８の軸方向の端部に過大な荷重が入力されにくくなるため、ゴムブッシュ２３８の早期劣化を防止することができる。
【００４６】
次に、上記の実施形態から把握し得る請求項に記載以外の発明について、以下にその作用効果と共に記載する。
【００４７】
（イ）前記弾性体を制動力受部と中間回転体の一方に突設された連結ピンの外周に加硫接着し、制動力受部と中間回転体の他方に設けられた凹部に、前記弾性体を連結ピンと共に圧入したことを特徴とする請求項２または３に記載の内燃機関のバルブタイミング制御装置。
【００４８】
この場合、極めて簡単な構造でありながら、制動力受部と中間回転体を弾性体を介して確実に連結することが可能となる。
【００４９】
（ロ）前記弾性体の外周面の少なくとも一部に、その弾性体よりも高硬度の当接部材を取り付け、その当接部材を前記凹部に圧入したことを特徴とする（イ）に記載の内燃機関のパルブタイミング制御装置。
【００５０】
この場合、弾性体の外周側の少なくとも一部が高硬度の当接部材を介して接触するため、弾性体の外周面の凹部への圧入に伴なう歪の発生や、経時使用による弾性体の外周面の摩耗その他の劣化を防止することができると共に、凹部からの弾性体の脱落を確実に防止することができる。
【００５１】
（ハ）前記当接部材を弾性体に加硫接着したことを特徴とする（ロ）に記載の内燃機関のバルブタイミング制御装置。
【００５２】
この場合、当接部材から弾性体が脱落する不具合を無くすことができる。
【００５３】
（ニ）前記弾性体を樽形状に形成したことを特徴とする（イ）に記載の内燃機関のバルブタイミング制御装置。
【００５４】
この場合、荷重入力時に弾性体の軸方向の端部に応力が集中する不具合を無くし、弾性体の耐久性を向上させることができる。
【００５５】
（ホ）前記制動力受部を円筒状のヒステリシス材と、そのヒステリシス材の端部に結合された別材料から成るプレート部材によって構成し、このプレート部材と中間回転体を所定の遊びを持たせて連係させたことを特徴とする請求項３に記載の内燃機関のバルブタイミング制御装置。
【００５６】
この場合、プレート部材を、ヒステリシス材に比較して材料コストが安く、造形の容易な材料によって形成することにより、製造コストの高騰を招くことなく、制動力受部と中間回転体の連係部を造形することが可能となる。
【００５７】
（ヘ）磁気誘導部材の前記プレート部材に臨む側の端面のうちの、内側極歯よりも径方向内側に凹部を設け、その凹部内に前記プレート部材の一部を突出させたことを特徴とする（ホ）に記載の内燃機関のバルブタイミング制御装置。
【００５８】
この場合、凹部は、磁気誘導部材の内側極歯よりも径方向内側にあって磁気誘導部材内の磁束の流れに殆ど影響を与えることがない。そして、この凹部内にプレート部材の一部を突出させたため、その分、プレート部材の磁気誘導部材と逆側の張り出しを小さくし、磁気誘導部材とプレート部材を組付けた状態における総軸長を短縮することができる。また、磁気誘導部材に凹部を設けた分、軽量化も可能となる。
【００５９】
（ト）前記プレート部材に環状の肉抜き部を設けたことを特徴とする（ホ）または（ヘ）に記載の内燃機関のバルブタイミング制御装置。
【００６０】
この場合、肉抜き部は環状であるため、プレート部材はアンバランスな慣性力を生じることなく、充分に軽量化される。
【図面の簡単な説明】
【図１】この出願の発明の一実施形態を示す縦断面図。
【図２】同実施形態を示す図１のＡ−Ａ線に沿う断面図。
【図３】同実施形態の作動状態を示す図２に対応の断面図。
【図４】同実施形態を示す分解斜視図。
【図５】同実施形態を示す部品の斜視図。
【図６】同実施形態を示す部品の正面図。
【図７】この出願の発明の他の実施形態を示す断面図。
【図８】この出願の発明のさらに他の実施形態を示す断面図。
【符号の説明】
１…カムシャフト
３…駆動リング（駆動回転体）
４…組付角操作機構
７…従動軸部材（従動回転体）
１８…中間回転体（回転部材）
２０…ヒステリシスブレーキ（電磁ブレーキ）
２２…磁気誘導部材（制動力発生部）
２３…内側極歯
２４…外側極歯
２５…電磁コイル（制動力発生部）
２６…ヒステリシスリング（制動力受部、ヒステリシス材）
３３…円環プレート（制動力受部）
３４，３５…軸受
３８…ゴムブッシュ（弾性体）[0001]
BACKGROUND OF THE INVENTION
The invention of this application relates to a valve timing control device for an internal combustion engine that variably controls the opening / closing timing of an intake-side or exhaust-side engine valve of the internal combustion engine in accordance with an operating state.
[0002]
[Prior art]
As this type of valve timing control device, there is one as described in JP-A-2001-41013.
[0003]
In this device, a housing (drive rotator) linked to a crankshaft via a timing chain or the like is rotatably assembled to an end portion of a camshaft, and a movable guide is guided by a radial guide formed on an inner end surface of the housing. A lever shaft (driven rotor) having a lever protruding radially outward is bolted to the end of the camshaft, and the movable guide portion and the lever are slidably engaged and supported along the radial direction. The lever of the shaft is pivotally connected by a link. An intermediate rotating body having a spiral guide is provided at a position facing the radial guide so as to be rotatable relative to the housing and the lever shaft, and is provided at one end in the axial direction of the movable guide portion. A plurality of substantially arc-shaped protruding protrusions are guided and engaged with the spiral guide. Further, the intermediate rotating body is biased by a mainspring spring toward the side where the rotation is advanced with respect to the housing, and appropriately receives a force on the side of delaying rotation by an electromagnetic brake.
[0004]
In the case of this device, when the electromagnetic brake is in the OFF state, the intermediate rotating body is positioned at the initial position with respect to the housing under the urging force of the spring, and the movable guide portion that meshes with the spiral guide with the ridge is It is displaced to the maximum in the radial direction and causes a link to maintain the assembly angle of the housing and the camshaft at the most retarded position or the most advanced position. Then, when the electromagnetic brake is turned on from this state, the intermediate rotating body is decelerated and rotates relatively to the delay side with respect to the housing, so that the movable guide portion that meshes with the spiral guide is displaced radially inward, The assembly angle of the housing and the camshaft is changed to the most advanced position or the most retarded position by gradually tilting the link that has been caused so far.
[0005]
In the electromagnetic brake, a braking force generating portion composed of an electromagnetic coil and a magnetic induction member is fixed to a non-rotating member such as a VTC cover, and the intermediate rotating body facing the end surface of the magnetic induction member directly receives the braking force. Has become a department.
[0006]
[Problems to be solved by the invention]
However, in the case of the conventional valve timing control device described above, the positional relationship between the braking force generating part (magnetic induction member) of the electromagnetic brake and the braking force receiving part (intermediate rotating body) is not constrained at all. When the tip of the camshaft fluctuates in the bending direction or the rotation direction, the distance between the braking force generation unit and the braking force receiving unit and the facing posture change due to the variation, and a desired braking force cannot be obtained. there is a possibility.
[0007]
Therefore, the invention of this application always maintains a stable operation performance by maintaining the distance between the braking force generating portion and the braking force receiving portion and the facing posture regardless of the fluctuation of the tip portion of the camshaft. It is an object of the present invention to provide an internal combustion engine valve timing control device.
[0008]
[Means for Solving the Problems]
As a means for solving the problems described above, the invention according to the claims 1, to fix the braking force generation portion of the electromagnetic brake to a non-rotating member, the braking force receiving portion of the electromagnetic brake, Ya the camshaft The brake force generator is disposed in a separated state with respect to the driven rotor, and is supported by the brake force generator via a bearing so that the brake force receiver is supported by the intermediate rotor of the assembly angle operation mechanism. I tried to make it work together.
[0009]
In the case of this invention, since the braking force receiving part is supported by the braking force generating part via the bearing, the distance between them is kept constant regardless of the input of external force. In addition, since the braking force receiving portion and the intermediate rotating body are linked with a predetermined play, a large load is not transmitted between the two as long as they do not move relative to each other beyond a predetermined distance. For this reason, the fluctuation of the camshaft becomes difficult to be input from the intermediate rotating body to the braking force receiving portion. Therefore, from these, it becomes possible to always keep the distance between the braking force generation unit and the braking force receiving unit and the facing posture constant, and as a result, the operability of the valve timing control device is stabilized.
[0010]
The braking force receiving portion and the intermediate rotating body are preferably connected via an elastic body. In this case, at the connecting portion between the braking force receiving portion and the intermediate rotating body, the elastic body can absorb the fluctuation of the tip of the camshaft. Can be eliminated.
[0011]
The braking force generator includes a plurality of pole teeth on a magnetic induction member having a pair of circumferential facing surfaces facing each other across a substantially cylindrical gap, and a radially inner surface of the pair of facing surfaces. A plurality of pole teeth elements are provided along the circumferential direction on the inner pole teeth whose elements are provided along the circumferential direction and the radially outer surface of the pair of opposing surfaces, and each pole tooth element Is configured to include an outer pole tooth that is offset in a circumferential direction with respect to the pole element of the inner pole tooth, and an electromagnetic coil that generates a magnetic field between the inner pole tooth and the outer pole tooth. The braking force receiving portion may include a hysteresis material having a cylindrical wall inserted into a gap between the inner pole teeth and the outer pole teeth.
[0012]
In such an electromagnetic brake using the magnetic hysteresis characteristics of the hysteresis material, a larger braking force is obtained as the distance between each pole tooth and the hysteresis material is reduced. Therefore, it is desirable to reduce the distance between the two as much as possible. However, as the distance between each pole tooth and the hysteresis material is reduced, when the hysteresis material fluctuates with respect to both pole teeth, the hysteresis material comes into contact with the pole teeth, which not only makes the brake control unstable. The contact parts are likely to be worn or damaged. In the brake used in this valve timing control device, the distance between the pole teeth of the hysteresis material, which is the braking force receiving portion, and the braking force generating portion is maintained constant by the bearing, and between the intermediate rotating body and the braking force receiving portion. Since the backlash is absorbed by the play between the two, it is possible to sufficiently reduce the distance between the two without causing contact between the hysteresis material and the pole teeth, thereby obtaining a large braking force.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the invention of this application will be described with reference to the drawings.
[0014]
In this embodiment, the valve timing control device according to the invention of this application is applied to the power transmission system on the intake side of the internal combustion engine, but can also be similarly applied to the power transmission system on the exhaust side.
[0015]
As shown in FIG. 1, the valve timing control device can rotate relative to a camshaft 1 rotatably supported by a cylinder head (not shown) of an internal combustion engine and a front end portion of the camshaft 1 as necessary. And a drive ring 3 (drive rotator) having a timing sprocket 2 on the outer periphery linked to a crankshaft (not shown) via a chain (not shown), and the drive ring 3 and the camshaft 1 1 is disposed on the front side (left side in FIG. 1), and the assembly angle operation mechanism 4 for operating the assembly angles of the both 3 and 1 is disposed further on the front side of the assembly angle operation mechanism 4. An operation force applying means 5 for driving the mechanism 4 and a front surface and a peripheral area of the assembly angle operation mechanism 4 and the operation force applying means 5 which are attached across the front surfaces of the cylinder head and the head cover (not shown) of the internal combustion engine. Outside VT And it includes a cover, a.
[0016]
The drive ring 3 is formed in a substantially disk shape having a step-like insertion hole 6, and this insertion hole 6 portion rotates to a driven shaft member 7 (driven rotary body) coupled to the front end portion of the camshaft 1. It is assembled as possible. Then, on the front surface of the drive ring 3 (the surface opposite to the camshaft 1), as shown in FIG. 2, three radial grooves 8 (radial guides) having parallel side walls facing each other are provided on the ring 3. It is formed so as to be substantially along the radial direction.
[0017]
Further, as shown in FIG. 1, the driven shaft member 7 has a diameter-enlarged portion formed on the base-side outer periphery that abuts the front end portion of the camshaft 1, and an outer peripheral surface on the front side of the enlarged-diameter portion. The three levers 9 projecting radially are integrally formed, and are coupled to the camshaft 1 by bolts 10 penetrating the shaft core portion. The base end of each link 11 is pivotally connected to each lever 9 by a pin 12, and a columnar protrusion 13 slidably engaged with each radial groove 8 is integrally formed at the tip of each link 11. Is formed.
[0018]
Each link 11 is connected to the driven shaft member 7 via the pin 12 in a state where the protruding portion 13 is engaged with the corresponding radial groove 8, so that the distal end side of the link 11 receives an external force and receives the radial groove. When displaced along 8, the drive ring 3 and the driven shaft member 7 are relatively rotated by the action of the link 11 by a direction and an angle corresponding to the displacement of the protrusion 13.
[0019]
In addition, a housing hole 14 that opens to the front side in the axial direction is formed at the tip of each link 11, and an engagement pin 16 that engages with a spiral groove 15 (a spiral guide), which will be described later, in the housing hole 14. A coil spring 17 that urges the engaging pin 16 forward (spiral groove 15 side) is accommodated. In the case of this embodiment, a movable guide portion that is displaceable in the radial direction is configured by the protruding portion 13 at the tip of the link 11, the engaging pin 16, the coil spring 17, and the like.
[0020]
On the other hand, an intermediate rotating body 18 having a disk-like flange wall is rotatably supported via a bearing 19 on the front side of the protruding position of the lever 9 of the driven shaft member 7. The aforementioned spiral groove 15 having a semicircular cross section is formed on the rear surface side of the flange wall of the intermediate rotating body 18, and the engagement pin 16 at the tip of each link 11 is rotatably guided in the spiral groove 15. Is engaged. The spiral of the spiral groove 15 is formed so as to gradually reduce the diameter along the engine rotation direction R. Therefore, when the intermediate rotating body 18 rotates relative to the drive ring 3 in the delay direction in a state where the engaging pin 16 at the tip of each link 11 is engaged with the spiral groove 15, the tip of the link 11 is in the radial groove 8. , Guided to the spiral shape of the spiral groove 15 and moved radially inward, and conversely, when the intermediate rotating body 18 is relatively displaced in the advance direction, it moves radially outward.
[0021]
In the figure, reference numerals 48 and 49 denote protrusions and stoppers that come into contact with each other when the drive ring 3 and the intermediate rotating body 18 are relatively rotated by a set angle or more to restrict the rotation of the three and 18.
[0022]
The assembly angle operation mechanism 4 includes the radial groove 8, the link 11, the protrusion 13, the engagement pin 16, the lever 9, the intermediate rotating body 18, and the spiral groove 15 of the drive ring 3 described above. In the assembly angle operation mechanism 4, when a relative rotation operation force with respect to the camshaft 1 is input from the operation force applying means 5 to the intermediate rotating body 18, the operation force is applied to the spiral groove 15 and the engagement pin 16. The distal end of the link 11 is displaced in the radial direction through the engaging portion, and at this time, relative rotational force is transmitted to the drive ring 3 and the driven shaft member 7 by the action of the link 11 and the lever 9.
[0023]
On the other hand, the operating force applying means 5 includes a mainspring 47 that biases the intermediate rotating body 18 in the engine rotation direction R with respect to the drive ring 3, and the intermediate rotating body 18 opposite to the engine rotation direction R with respect to the drive ring 3. The intermediate rotating body 18 includes a hysteresis brake 20 (electromagnetic brake) which is a braking mechanism for biasing in the direction, and appropriately controls the braking force of the hysteresis bushcake 20 according to the operating state of the internal combustion engine. Is rotated relative to the drive ring 3, or the rotational positions of both are maintained.
[0024]
The spring spring 47 has an outer peripheral end portion coupled to the cylindrical wall 21 extending to the drive ring 3, while an inner peripheral end portion is coupled to a cylindrical base portion of the intermediate rotating body 18, and the entire spring body 47 is an intermediate rotating body. It arrange | positions in the front side space of 18 flange walls. A sealing wall 50 is integrally coupled to the end surface of the intermediate rotating body 18 opposite to the camshaft 1, and the outer peripheral surface of the sealing wall 50 is slidably in close contact with the inner surface of the cylindrical wall 21. ing. A pair of connecting pins 53 whose front end portions protrude in the direction opposite to the camshaft 1 are attached to the intermediate rotating body 18 through the sealing wall 50. The connecting pin 53 will be described later.
[0025]
On the other hand, the hysteresis brake 20 is attached to a VTC cover, which is a non-rotating member, and has a pair of circumferentially opposed magnetic induction members 22 facing each other across a substantially cylindrical gap, and both the opposing surfaces. Inner pole teeth 23 and outer pole teeth 24 provided, an electromagnetic coil 25 attached to the magnetic induction member 22 to generate a magnetic field between the inner pole teeth 23 and the outer pole teeth 24, and the intermediate rotating body 18 And a cylindrical hysteresis ring 26 inserted between the two pole teeth 23 and 24 in a state of being connected to each other, and the electromagnetic coil 25 is energized and controlled by a controller (not shown).
[0026]
In this embodiment, the hysteresis brake 20 is unitized as shown in FIGS.
[0027]
The magnetic induction member 22 includes an inner tooth ring 27 having inner pole teeth 23 on the outer peripheral surface, an outer tooth ring 28 having outer pole teeth 24 on the inner peripheral surface, and a connection for connecting the inner tooth ring 27 and the outer tooth ring 28. And a ring 29. An annular step portion is provided on the outer peripheral corner portion of the connecting ring 29 facing the pole teeth 23 and 24, and the electromagnetic coil 25 is fitted and mounted on the step portion.
[0028]
Each of the inner pole teeth 23 and the outer pole teeth 24 has a plurality of pole teeth elements extending along the axial direction. The pole teeth elements of the pole teeth 23 and 24 are respectively arranged along the circumferential direction, and the pole tooth elements of the pole teeth 23 and 24 are offset from each other in the circumferential direction. Therefore, when the electromagnetic coil 25 is energized, a magnetic field is generated between the pole teeth 23 and 24 toward the counterpart pole tooth element having an offset positional relationship.
[0029]
A harness 25 a for energizing the electromagnetic coil 25 penetrates the magnetic induction member 22 (external tooth ring 28) radially outward and is drawn to the outside from the outer peripheral surface side of the magnetic induction member 22. Since the cross-sectional area of the magnetic path in the magnetic induction member 22 can be secured larger toward the outer side in the radial direction, when the harness lead-out portion is provided so as to penetrate the magnetic induction member 22 outward in the radial direction as in this embodiment, the harness The influence of the loss of the magnetic path cross-sectional area due to the provision of the drawer portion is reduced.
[0030]
On the other hand, the hysteresis ring 20 is made of a hysteresis material having magnetic hysteresis characteristics, and a metal annular plate 33 (plate member) is fitted and fixed to the end portion protruding from the gap between the bipolar teeth 23 and 24. Has been. The annular plate 33 is integrally coupled to a stainless steel shaft member 36 supported on the inner peripheral surface of the connecting ring 29 via bearings 34 and 35. Therefore, the hysteresis ring 20 is supported by the magnetic induction member 22 via the annular plate 33 and the shaft member 36 so as to be relatively rotatable. Since the shaft member 36 is made of stainless steel which is a non-magnetic material, there is no problem that foreign matter is attracted to the shaft member 36 when the magnetic flux of the electromagnetic coil 25 passes through the shaft member 36.
[0031]
In addition, a pair of circular recesses 37 are provided on the back surface (the surface on the camshaft 1 side) of the annular plate 33, and each recess 37 has an intermediate rotating body 18 side via a rubber bush 38 (elastic body). The connecting pin 53 is fitted. Therefore, the annular plate 33 and the hysteresis ring 20 rotate integrally with the intermediate rotating body 18 via the rubber bush 38 and the connecting pin 53. Since the rubber bush 38 has elasticity and allows a slight relative displacement between the connecting pin 53 and the recess 37, it can be said that the annular plate 33 and the intermediate rotating body 18 are linked with a predetermined play. . In addition, an annular lightening groove 31 (a lightening part) is provided on the outer peripheral edge of the back surface of the annular plate 33, and the lightening of the annular plate 33 without causing rotation imbalance by the lightening groove 31. Is planned.
[0032]
In the case of this embodiment, the rubber bush 38 is formed in a cylindrical shape having a substantially constant thickness and is vulcanized and bonded to the outer peripheral surface of the connecting pin 53 in advance. The rubber bush 38 at the tip of each connecting pin 53 is press-fitted into the recess 37 of the annular plate 33 when the hysteresis brake 20 is installed.
[0033]
Here, as shown in FIGS. 1 and 4, the annular plate 33 is sandwiched between the head portion 36 a of the shaft member 36 and the nut 41 together with the bearings 34 and 35 and the spacer 40, so that the magnetic induction member 22. However, the end surface of the magnetic induction member 22 on the annular plate 33 side is provided with a recess 30 that is recessed in the axial direction from the radially inner position with respect to the inner pole teeth 23, and the annular plate A radially inner region 33 projects into the recess 30. Of the annular plate 33, the concave portion 37 with which the connecting pin 53 is engaged and the seating surface of the head portion 36a of the shaft member 36 are arranged so as to be offset from the portion protruding to the concave portion 30 side. . Therefore, the axial length when the magnetic induction member 22 and the annular plate 33 are assembled is shortened by providing the magnetic induction member 22 with the recess 30.
[0034]
Further, the assembly of the annular plate 33 to the magnetic induction member 22 will be described in more detail. First, the bearing 34 on the annular plate 33 side is formed in the center hole of the magnetic induction member 22 (connection ring 29). The bearing 34 is inserted until it comes into contact with the substantially central projection 32, and the outer race of the bearing 34 is caulked and fixed to the hole edge of the magnetic induction member 22 on the annular plate 33 side. Next, the shaft member 36 into which the annular plate 33 is inserted and engaged is press-fitted into the inner race of the bearing 34 from the tip end side. Thereby, the shaft member 36 is locked to the magnetic induction member 22 via the bearing 34, and the annular plate 33 is also locked at this time. Thereafter, the spacer 40 is inserted into the shaft member 36 from the opposite side of the center hole, and the other bearing 35 is press-fitted into the shaft member 36 until the inner race hits the spacer 40. A nut 41 is screwed onto the tip of 36. The inner races of the bearings 34 and 35 and the annular plate 33 are fixed to each other by tightening the nut 41. However, the axial length of the protrusion 32 on the inner periphery of the magnetic induction member 22 is set to be shorter than the axial length of the spacer 40, and even when the nut 41 is tightened, the outer race of the bearing 35 is It cannot be pressed against the protrusion with excessive force.
[0035]
In this embodiment, the braking force generator of the hysteresis brake 20 is constituted by a magnetic induction member 22 including pole teeth 23 and 24 and an electromagnetic coil 25, and the braking force receiver is configured by a hysteresis ring 26 and an annular ring. A plate 33 is used.
[0036]
Since this valve timing control device has the above-described configuration, when the internal combustion engine is started or idling, the excitation of the electromagnetic coil 25 of the hysteresis brake 20 is turned off so that the intermediate spring is rotated by the force of the mainspring spring 47. The body 18 is rotated to the maximum in the engine rotation direction R with respect to the drive ring 3 (see FIG. 2). As a result, the rotational phase of the crankshaft and the camshaft 1 (the opening / closing timing of the engine valve) is maintained at the most retarded angle side, and the engine rotation is stabilized and the fuel consumption is improved.
[0037]
When the engine operation is shifted to the normal operation from this state and a command to change the rotational phase to the most advanced angle side is issued from a controller (not shown), the excitation of the electromagnetic coil 25 of the hysteresis brake 20 is turned on. The braking force against the mainspring spring 47 is transmitted from the annular plate 33 to the intermediate rotating body 18 via the rubber bush 38 and the connecting pin 53. Thereby, the intermediate rotating body 18 rotates in the opposite direction with respect to the drive ring 3, whereby the engaging pin 16 at the tip of the link 11 is guided to the spiral groove 15, and the tip of the link 11 becomes the radial groove 8. As shown in FIG. 3, the assembly angle of the drive ring 3 and the driven shaft member 7 is changed to the most advanced angle side by the action of the link 11 as shown in FIG. As a result, the rotational phase of the crankshaft and the camshaft 1 is changed to the most advanced angle side, thereby increasing the engine output.
[0038]
Further, when a command is issued from the controller to change the rotational phase to the most retarded side from this state, the excitation of the electromagnetic coil 25 of the hysteresis brake 20 is turned off, and the intermediate rotor is again driven by the force of the mainspring spring 47. 18 is rotated in the engine rotation direction R. Then, the link 11 swings in the direction opposite to the above by the guide of the engaging pin 16 by the spiral groove 15, and the assembly angle of the driven shaft member 7 of the drive ring 3 is caused by the action of the link 11 as shown in FIG. It is changed to the retard side again.
[0039]
Note that the rotational phase of the crankshaft and the camshaft 1 by this valve timing control apparatus is not limited to the two phases of the most retarded angle and the most advanced angle described above, but can be arbitrarily set by controlling the braking force of the hysteresis brake 20. By changing to the phase, the phase can be maintained by the balance between the force of the mainspring spring 47 and the braking force of the hysteresis brake 20.
[0040]
By the way, in this valve timing control device, an annular plate 33 on the braking force receiving portion side of the hysteresis brake 20 is supported by the magnetic induction member 22 on the braking force generating portion side via bearings 34 and 35, and Since the plate 33 and the intermediate rotator 18 are linked with a predetermined allowance via the rubber bush 38, the intermediate rotator 18 changes in the bending direction and the rotation direction integrally with the camshaft 1 during engine operation. Even if there is, there is no problem that the ring plate 33 is loose due to the fluctuation. Therefore, the hysteresis ring 26 integrated with the annular plate 33 is always maintained at a constant interval and posture with respect to the inner pole teeth 23 and the outer pole teeth 24. Therefore, the hysteresis brake 20 can exhibit stable braking performance even if the gap between the hysteresis ring 26 and the pole teeth 23 and 24 is sufficiently narrowed in order to ensure a large braking force. This ensures that the operating performance of the device is improved.
[0041]
In the case of the valve timing control device of this embodiment, since the rubber bush 38 is interposed between the tip of the connecting pin 53 projecting from the intermediate rotating body 18 and the recess 37 of the annular plate 33, the cam The fluctuation of the intermediate rotating body 18 integrated with the shaft 1 can be allowed in the rubber bush 38 portion, and the generation of a rattling sound and an impact due to the relative displacement of the connecting pin 53 and the concave portion 37 is caused by the elasticity of the rubber bush 38. Can be prevented.
[0042]
In this embodiment, the hysteresis material (hysteresis ring 26) of the hysteresis brake 20 is formed in a cylindrical shape as a whole and connected to the intermediate rotating body 18 via an annular plate 33 which is a separate member. As long as it has a cylindrical wall interposed between the teeth 23 and 24 in a non-contact state, the whole may be formed into a bottomed cylindrical shape or other shapes. However, when the hysteresis member is formed in a cylindrical shape and a separate plate member (annular plate 33) is attached to the end thereof as in this embodiment, the connecting portion with the intermediate rotating body 18 is Since the material cost is low and the material can be formed with a material that can be easily shaped, the manufacturing cost of the entire product can be reduced.
[0043]
Further, the tip of the connecting pin 53 can adopt other forms as shown in FIGS.
[0044]
FIG. 7 shows that a cylindrical abutting member 45 made of a high hardness material such as a metal is vulcanized and bonded to the outer peripheral surfaces of both ends of the rubber bush 138 in the axial direction, and the outer peripheral surface of the abutting member 45 is attached to an annular plate. It is configured to press fit into the concave portion 37 of 33. In this case, since the abutting member 45 with a high hardness abuts against the recess 37, the rubber bush 138 is deformed by pressing the rubber bush 138 into the recess 37, or the outer periphery of the rubber bush 138 is used over time. The wear of the surface can be prevented, and the rubber bush 138 can be prevented from falling off from the recess 37.
[0045]
FIG. 8 shows the rubber bush 238 formed in a barrel shape. In this case, it is difficult for an excessive load to be input to the end portion of the rubber bush 238 in the axial direction, so that early deterioration of the rubber bush 238 can be prevented.
[0046]
Next, inventions other than those described in the claims that can be grasped from the above-described embodiment will be described together with the effects thereof.
[0047]
(A) The elastic body is vulcanized and bonded to the outer periphery of a connecting pin protruding from one of the braking force receiving portion and the intermediate rotating body, and the recess is provided on the other of the braking force receiving portion and the intermediate rotating body. 4. The valve timing control device for an internal combustion engine according to claim 2, wherein the elastic body is press-fitted together with the connecting pin.
[0048]
In this case, it is possible to reliably connect the braking force receiving portion and the intermediate rotating body via the elastic body while having an extremely simple structure.
[0049]
(B) A contact member having a hardness higher than that of the elastic body is attached to at least a part of the outer peripheral surface of the elastic body, and the contact member is press-fitted into the recess. A valve timing control device for an internal combustion engine.
[0050]
In this case, since at least a part of the outer peripheral side of the elastic body comes into contact with the contact member having high hardness, the elastic body is caused by generation of strain accompanying press-fitting into the concave portion of the outer peripheral surface of the elastic body, It is possible to prevent wear and other deterioration of the outer peripheral surface of the elastic member, and to reliably prevent the elastic body from dropping from the recess.
[0051]
(C) The valve timing control device for an internal combustion engine according to (b), wherein the contact member is vulcanized and bonded to an elastic body.
[0052]
In this case, it is possible to eliminate the problem that the elastic body drops from the contact member.
[0053]
(D) The valve timing control device for an internal combustion engine according to (a), wherein the elastic body is formed in a barrel shape.
[0054]
In this case, it is possible to eliminate the problem of stress concentration at the axial end of the elastic body when a load is input, and to improve the durability of the elastic body.
[0055]
(E) The braking force receiving portion is constituted by a cylindrical hysteresis member and a plate member made of another material coupled to the end of the hysteresis member, and the plate member and the intermediate rotating body have predetermined play. The valve timing control device for an internal combustion engine according to claim 3, wherein the valve timing control device is linked.
[0056]
In this case, the plate member is formed of a material that is cheaper than the hysteresis material and easy to form, so that the linkage portion between the braking force receiving portion and the intermediate rotating body can be provided without causing an increase in manufacturing cost. It becomes possible to model.
[0057]
(F) A concave portion is provided on the radially inner side of the end face facing the plate member of the magnetic induction member, and a part of the plate member is protruded into the concave portion. The valve timing control device for an internal combustion engine according to (6).
[0058]
In this case, the concave portion is radially inward of the inner pole teeth of the magnetic induction member and hardly affects the flow of magnetic flux in the magnetic induction member. And since a part of plate member protruded in this recessed part, the protrusion on the opposite side to the magnetic induction member of a plate member is made small, and the total axial length in the state which assembled | attached the magnetic induction member and the plate member was reduced. It can be shortened. Further, the weight can be reduced by providing the magnetic guide member with the concave portion.
[0059]
(G) The valve timing control device for an internal combustion engine according to (e) or (f), wherein the plate member is provided with an annular lightening portion.
[0060]
In this case, since the thinned portion is annular, the plate member is sufficiently reduced in weight without causing an unbalanced inertia force.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an embodiment of the invention of this application.
2 is a cross-sectional view taken along the line AA of FIG. 1 showing the embodiment.
3 is a cross-sectional view corresponding to FIG. 2 showing an operating state of the embodiment.
FIG. 4 is an exploded perspective view showing the embodiment.
FIG. 5 is a perspective view of a component showing the embodiment.
FIG. 6 is a front view of a part showing the embodiment;
FIG. 7 is a cross-sectional view showing another embodiment of the invention of this application.
FIG. 8 is a sectional view showing still another embodiment of the invention of this application.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Cam shaft 3 ... Drive ring (drive rotary body)
4 ... Assembly angle operating mechanism 7 ... Driven shaft member (driven rotor)
18 ... Intermediate rotating body (rotating member)
20 ... Hysteresis brake (electromagnetic brake)
22 ... Magnetic induction member (braking force generating part)
23 ... Inner pole teeth 24 ... Outer pole teeth 25 ... Electromagnetic coil (braking force generator)
26 ... Hysteresis ring (braking force receiving part, hysteresis material)
33 ... Ring plate (braking force receiving part)
34, 35 ... bearing 38 ... rubber bush (elastic body)

Claims

A drive rotator that is rotationally driven by a crankshaft of an internal combustion engine, a driven rotator comprising a camshaft or a separate member coupled to the shaft, and a rotatable relative to the drive rotator and the driven rotator. An assembly angle operating mechanism for changing an assembly angle between the drive rotator and the driven rotator by rotating the intermediate rotator, and rotating the same rotator to the intermediate rotator; In an internal combustion engine valve timing control device comprising: an electromagnetic brake that applies a braking force for dynamic operation;
While fixing the braking force generator of the electromagnetic brake to the non-rotating member,
Wherein the braking force receiving portion of the electromagnetic brake, through a bearing is relatively rotatably supported on the cam shaft and disposed vital said braking force generating unit to the separated state with respect to the driven rotating body,
A valve timing control device for an internal combustion engine, wherein the braking force receiving portion is linked with an intermediate rotating body of an assembly angle operation mechanism with a predetermined play.

A drive rotator that is rotationally driven by a crankshaft of an internal combustion engine, a driven rotator comprising a camshaft or a separate member coupled to the shaft, and a rotatable relative to the drive rotator and the driven rotator. An assembly angle operating mechanism for changing an assembly angle between the drive rotator and the driven rotator by rotating the intermediate rotator, and rotating the same rotator to the intermediate rotator; In an internal combustion engine valve timing control device comprising: an electromagnetic brake that applies a braking force for dynamic operation;
While fixing the braking force generator of the electromagnetic brake to the non-rotating member,
The braking force receiving portion of the electromagnetic brake is disposed in a separated state with respect to the camshaft and the driven rotating body, and is supported by the braking force generation portion via a bearing so as to be relatively rotatable.
A valve timing control device for an internal combustion engine, wherein the braking force receiving portion is connected to an intermediate rotating body of an assembly angle operating mechanism via an elastic body.

The braking force generator includes a plurality of poles on a magnetic induction member having a pair of circumferential facing surfaces facing each other across a substantially cylindrical gap, and a radially inner surface of the pair of facing surfaces. A plurality of pole teeth elements are provided along the circumferential direction on the inner pole teeth provided along the circumferential direction and the radially outer surface of the pair of opposing surfaces, and each pole tooth A configuration comprising outer pole teeth whose elements are circumferentially offset with respect to the pole tooth elements of the inner pole teeth, and electromagnetic coils that generate a magnetic field between the inner pole teeth and the outer pole teeth age,
3. The internal combustion engine according to claim 1, wherein the braking force receiving portion includes a hysteresis material having a cylindrical wall inserted into a gap between the inner pole teeth and the outer pole teeth. Valve timing control device.

The elastic body is vulcanized and bonded to the outer periphery of a connecting pin projecting from one of the braking force receiving portion and the intermediate rotating body, and the recess is provided on the other of the braking force receiving portion and the intermediate rotating body. 4. The valve timing control device for an internal combustion engine according to claim 2, wherein the elastic body is press-fitted together with the connecting pin.

The internal combustion engine according to claim 4, wherein a contact member having a hardness higher than that of the elastic body is attached to at least a part of an outer peripheral surface of the elastic body, and the contact member is press-fitted into the recess. Valve timing control device.

6. The valve timing control device for an internal combustion engine according to claim 5, wherein the contact member is vulcanized and bonded to an elastic body.

The valve timing control device for an internal combustion engine according to claim 4, wherein the elastic body is formed in a barrel shape.

The braking force receiving portion is constituted by a cylindrical hysteresis material and a plate member made of another material coupled to the end of the hysteresis material, and the plate member and the intermediate rotating body are linked with a predetermined play. The valve timing control apparatus for an internal combustion engine according to claim 3, wherein

The concave part is provided in the diameter direction inner side of the end face of the magnetic induction member facing the plate member, and a part of the plate member is protruded in the concave part. The valve timing control device for an internal combustion engine according to claim 8.

The valve timing control device for an internal combustion engine according to claim 8 or 9, wherein the plate member is provided with an annular lightening portion.