JP2004232823A

JP2004232823A - Tubular vibration damper

Info

Publication number: JP2004232823A
Application number: JP2003025089A
Authority: JP
Inventors: Kazuhiko Kato; 和彦加藤; Naoki Nishi; 直樹西
Original assignee: Sumitomo Riko Co Ltd
Current assignee: Sumitomo Riko Co Ltd
Priority date: 2003-01-31
Filing date: 2003-01-31
Publication date: 2004-08-19
Anticipated expiration: 2023-01-31
Also published as: JP4218358B2

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an outer cylinder from coming off and revolving well even in case of an outer tube of a resin in a tubular vibration damper wherein a rubber bush having an inner tube, an outer tube and a rubber elastomer is pressed into a tubular counter member. <P>SOLUTION: In the tubular vibration damper that presses a rubber bush 10 having the resin outer tube 28 is pressed into a rigid counter member 12, a first engagement face 20 with a step face for the axial engagement is formed on an inner face of the counter member 12 and formed with step copying the inner shape of the counter member 12 by pressing the outer tube 28 into the counter member 12 utilizing the elasticity of a resin and the shape and then the first face to be engaged is formed on the outer tube 28. Also a third engagement face 24 of whirl stop by engaging to a circumferential direction and the face 36 to be engaged are formed so that those are engaged with each other. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
この発明はゴムブッシュを筒形の相手部材に圧入し嵌合状態に保持するようになした筒形防振装置に関し、特にゴムブッシュの外筒が樹脂にて構成されたものに関する。
【０００２】
【従来の技術】
従来より、剛性の外筒及び内筒と、それら外筒及び内筒間に配置されたゴム弾性体とを有するゴムブッシュを、外筒の外面において筒形の剛性の相手部材に圧入して、ゴムブッシュを相手部材にて嵌合状態に保持するようになした筒形防振装置が、自動車のトレーリングアームブッシュ，トルクロッドブッシュ等のサスペンションブッシュやエンジンマウント等として広く用いられている。
【０００３】
この種の筒形防振装置は、従来ゴムブッシュの外筒，内筒，相手部材が何れも金属製であり、ゴムブッシュの外筒を所定の締め代で相手部材に圧入すると、外筒の外面と相手部材の内面との間に発生する強い摩擦力に基づいてゴムブッシュが相手部材から抜け防止される。
【０００４】
ところで、近年ゴムブッシュの外筒を樹脂化することが検討されており、この場合、樹脂から成る外筒の弾性復元力が応力緩和により低下し、更に熱影響を受けることにより大きく応力緩和を生じ、初期には所定の締め代をもって圧入したとしても、その後の経時変化により外筒の相手部材に対する弾性復元力が低下し、抜き力が低下してしまう問題が内在する。
【０００５】
この問題の対策の一例が下記特許文献１に開示されている。
図１３はその具体例を示している。同図において２００はゴムブッシュで、金属製の内筒２０２と、その外周面に一体に固着されたゴム弾性体２０４と、更にそのゴム弾性体２０４の外周面に一体に固着された樹脂製の外筒２０６とを有している。
２０８は金属製の筒形をなす相手部材で、ゴムブッシュ２００は、この相手部材２０８内部に圧入されて嵌合状態に保持されている。
【０００６】
樹脂製の外筒２０６は、軸方向端部（図中下端部）に鍔部２１０を有しており、その鍔部２１０の、相手部材２０８の軸端面への当接によって図１３中上方向へのゴムブッシュ２００の抜けが防止されている。
また外筒２０６はこれとは反対側の軸方向端部且つ相手部材２０８から軸方向に突き出した部分に、互いに逆方向に傾斜する傾斜面２１４，２１６を備えた部分的に厚肉の係合部２１８を有しており、ゴムブッシュ２００を相手部材２０８に圧入した後においてこの係合部２１８を相手部材２０８の軸端面、詳しくは鍔部２１０とは反対側の軸端面に係合させることによって、ゴムブッシュ２００を相手部材２０８から図１３中下方向への抜け防止をなしている。
【０００７】
【特許文献１】
実開平５−７７６３７号公報
【０００８】
【発明が解決しようとする課題】
しかしながらこの特許文献１に開示のものは、相手部材２０８に対するゴムブッシュ２００の回止めが特になされておらず、相手部材２０８に対して圧入されたゴムブッシュ２００の樹脂製の外筒２０６の弾性復元力が応力緩和により低下したとき、かかるゴムブッシュ２００が相手部材２０８に対し相対回転してしまう恐れが生ずる。
【０００９】
また図１３に示す筒形防振装置の場合、外筒２０６の一部、詳しくは係合部２１８の部分が相手部材２０８から軸方向に突き出して外部に露出し、外気に曝されていることから劣化を生じ易い問題の他、相手部材２０８から突き出して露出した部分に飛び石等が当ったりして割れを生じ易い問題がある。
【００１０】
更にこの筒形防振装置の場合、必然的にゴムブッシュ２００の軸方向長、詳しくは鍔部２１０を除いた部分の軸方向長が相手部材２０８よりも長くなければならず、形状的な制約を受ける問題がある。
【００１１】
【課題を解決するための手段】
本発明の筒形防振装置はこのような課題を解決するために案出されたものである。
而して請求項１のものは、樹脂製の外筒と、内筒と、それら外筒及び内筒間に配置されたゴム弾性体とを有するゴムブッシュを、該外筒の外面において筒形の剛性の相手部材に圧入して該ゴムブッシュを該相手部材にて嵌合状態に保持するようになした筒形防振装置において、前記相手部材の内面に、径方向外方に凹陥した形態の凹陥部を軸方向に部分的に形成して、該凹陥部と非凹陥部との境界部に段付面から成る軸方向係合用の第１の係合面を形成する一方、前記外筒の外面を該相手部材への圧入前の状態で前記非凹陥部よりも大径となし、樹脂の弾性を利用して該外筒を縮径させながら該相手部材内部に圧入して、該外筒の外面形状を該相手部材の内面形状に倣った段付形状に弾性変形させ、該外筒に前記第１の係合面に対応した形状の段付面から成る第１の被係合面を形成して該第１の係合面とともに第１の係合部を構成せしめ、それら第１の係合面及び第１の被係合面を軸方向に係合させるとともに、軸方向の他の位置において前記相手部材と外筒とにそれら第１の係合面及び第１の被係合面の係合の向きとは軸方向において逆向きに係合する第２の係合面及び第２の被係合面を形成してそれらにより第２の係合部を構成せしめ、且つ前記第１の係合部及び第２の係合部の少なくとも何れか一方における係合面及び被係合面に、周方向に係合して回止めをなす第３の係合面及び第３の被係合面を形成してそれらにより第３の係合部を構成せしめたことを特徴とする。
【００１２】
請求項２のものは、請求項１において、前記第１の係合部及び第２の係合部における前記第３の係合部を形成していない側の係合面及び被係合面を、軸直角方向の面として形成したことを特徴とする。
【００１３】
請求項３のものは、請求項１，２の何れかにおいて、前記相手部材の軸端面及び該軸端面に重合する鍔付ゴムブッシュにおける前記外筒の鍔部の重合面を、前記第２の係合面及び被係合面となしたことを特徴とする。
【００１４】
請求項４のものは、請求項３において、前記第２の係合面及び被係合面を軸直角方向に対して傾斜した傾斜面となして、それら第２の係合面及び被係合面全体に亘って前記回止め用の第３の係合面及び被係合面を形成したことを特徴とする。
【００１５】
請求項５のものは、請求項３において、前記第１の係合面及び被係合面を軸直角方向に対して傾斜した傾斜面となして、それら第１の係合面及び被係合面全体に亘って前記回止め用の第３の係合面及び被係合面を形成する一方、前記第２の係合面及び被係合面を軸直角方向の面となしたことを特徴とする。
【００１６】
請求項６のものは、請求項１，２の何れかにおいて、前記相手部材の軸方向の一端部に第１の凹陥部を、他端部に第２の凹陥部を設けて、それら凹陥部と軸方向中間部の非凹陥部との境界部に、軸方向において互いに逆向きをなす第１の係合面と第２の係合面とを形成して、それらを前記外筒に形成された対応する第１の被係合面と第２の被係合面とに係合させ、且つ前記第１の係合部及び第２の係合部の少なくとも何れか一方における係合面及び被係合面に、前記第３の係合面及び被係合面を形成したことを特徴とする。
【００１７】
請求項７のものは、請求項６において、前記第１の係合部及び第２の係合部の少なくとも何れか一方における係合面及び被係合面を軸直角方向に対して傾斜した傾斜面となし、該傾斜面を前記第３の係合面及び被係合面となしたことを特徴とする。
【００１８】
請求項８のものは、請求項１〜７の何れかにおいて、前記外筒の外面を前記相手部材への圧入前の状態で実質的に軸方向のストレート形状となしてあることを特徴とする。
【００１９】
請求項９のものは、請求項１，２，６〜８の何れかにおいて、前記ゴムブッシュが前記外筒の軸方向端に鍔部を有しない鍔無しのものであることを特徴とする。
【００２０】
【作用及び発明の効果】
以上のように本発明は、ゴムブッシュにおける樹脂製の外筒を相手部材に圧入して、その外筒の外面形状を相手部材の内面形状に倣った段付形状に弾性変形させ、以って相手部材の段付面からなる第１の係合面に対して軸方向に係合する第１の被係合面を外筒に形成するとともに、これとは軸方向の他の位置において相手部材と外筒とに、それら第１の係合面及び被係合面の係合の向きとは軸方向において逆向きに係合する第２の係合面及び被係合面を形成し、且つ上記第１の係合面及び被係合面からなる第１の係合部および第２の係合面及び被係合面からなる第２の係合部の少なくとも何れか一方における係合面及び被係合面に、周方向に係合して回止めをなす第３の係合面及び被係合面を形成したものである。
【００２１】
かかる本発明によれば、圧入後の外筒を相手部材に対し軸方向の一方向にも、またこれとは反対向きの他方向にも良好に抜止めすることができる。
また本発明では、周方向に係合して回止めをなす第３の係合部が上記第１の係合部及び第２の係合部の少なくとも何れか一方に形成してあるため、軸方向の抜けと併せてゴムブッシュを回転方向にも移動阻止することができる。
【００２２】
また本発明は、第１の係合部において相手部材の内面と外筒の外面とを係合させるものであり、従って図１３に示す筒形防振装置のように、係合部を相手部材より軸方向外側に突き出した部分に設けることによって、その係合部が外気に曝されて劣化し、また飛び石等が当って割れを生じるなどの問題を回避することが可能となる。
また少なくとも第１の係合部を設けることによって、それだけ外筒即ちゴムブッシュが軸方向に長くなってしまうといった問題も解決することが可能となる。
【００２３】
ここで第１の係合部及び第２の係合部における上記第３の係合部を形成していない側の係合面及び被係合面は、軸直角方向の面となしておくことができる（請求項２）。
【００２４】
また本発明では、相手部材の軸端面及びこれに重合するゴムブッシュの外筒の鍔部の重合面を、上記第２の係合面及び被係合面となすことができる（請求項３）。
【００２５】
この場合において第２の係合面及び被係合面、即ち相手部材の軸端面及びゴムブッシュの鍔部の重合面を、軸直角方向に対して傾斜した傾斜面となしてそれら第２の係合面及び被係合面、つまり相手部材の軸端面及びゴムブッシュの鍔部の重合面全体に亘って上記第３の係合面及び被係合面を形成しておくことができる（請求項４）。
【００２６】
或いはまた請求項５に従って上記段付面からなる第１の係合面及び被係合面を傾斜面となして、それら全体に亘り回止め用の第３の係合面及び被係合面を形成しておく一方、前記第２の係合面及び被係合面を軸直角方向の面となしておくことができる。
【００２７】
一方請求項６のものは、相手部材の軸方向の一端部に第１の凹陥部を、他端部に第２の凹陥部を設けることによって、軸方向に互いに逆向きをなす第１の係合面と第２の係合面とを形成し、またゴムブッシュの外筒に対応した第１の被係合面と第２の被係合面とを形成してそれらを互いに係合させ、ゴムブッシュを相手部材から軸方向の一方向と他方向とに抜止めするとともに、第１の係合部及び第２の係合部の少なくとも何れか一方における係合面及び被係合面に、回止め用の第３の係合面及び被係合面を形成したもので、この場合においてもゴムブッシュを軸方向の一方向と他方向との両方向に良好に抜止めすることができるとともに、併せて相手部材に対するゴムブッシュの回転移動を阻止することができる。
【００２８】
この請求項６によれば、ゴムブッシュとして外筒が軸方向端部に鍔部を有しないものを用いることも可能となる（請求項９）。
而してそのような鍔部を有しないゴムブッシュを用いることができれば、筒形防振装置におけるゴムブッシュの形状を単純化でき、ゴムブッシュに要するコストを低減することができるとともに、相手部材に対してゴムブッシュを圧入する際の方向性が制約されなくなり、圧入作業性も良好となる。
【００２９】
尚この請求項６において、第３の係合面及び被係合面は周方向の段付面となすこともできるが（この点は請求項１〜５においても同様）、かかる請求項６において、第１の係合部及び第２の係合部の少なくとも何れか一方における係合面及び被係合面を軸直角方向に対する傾斜面となし、上記第３の係合面及び被係合面を兼ねたものとなしておくことができる（請求項７）。
【００３０】
また本発明において、外筒の外面を相手部材への圧入前の状態で実質的に軸方向のストレート形状となしておくことができる（請求項８）。
【００３１】
【実施例】
次に本発明の実施例を図面に基づいて詳しく説明する。
この例は自動車のトーションビーム式リヤサスペンションにおけるトレーリングアームと車体との連結部分に用いられる筒形防振装置の例で、図２はゴムブッシュ１０を、図３は図２のゴムブッシュ１０を圧入すべき相手部材１２を、図１は図３の相手部材１２に図２のゴムブッシュ１０を圧入して組み付けた状態をそれぞれ示している。
尚、図１において１４は相手部材１２から延び出したアームである。
【００３２】
図３に示しているように、相手部材１２は全体としてゴムブッシュ１０に対応した円筒形状をなしている。
ここで相手部材１２はその全体が金属にて構成されている。
相手部材１２の内面には、軸方向の一端部（図３（Ｂ）中右端部）に、径方向外方に凹陥した環状の凹陥部（第１の凹陥部）１６が設けられており、かかる凹陥部１６と非凹陥部１８との境界に段付面が形成されている。
ここで凹陥部１６は図４に示しているように軸方向長がＬ_２とされている。
【００３３】
本例において、この段付面は第１の係合面２０を成すものである。ここで段付面からなる第１の係合面２０は軸直角方向の面とされている。
本例において、この凹陥部１６を設けたのとは反対側の軸端面は第２の係合面２２とされている。
この第２の係合面２２は、図４に示しているようにその全体が軸直角方向に対し角度θで傾斜する傾斜面をなしている。
即ち本例では第２の係合面２２の全体が同時に回止め用の第３の係合面２４を成している。
【００３４】
ここで凹陥部１６の内径Ｄ_２（図４参照）は、圧入前のゴムブッシュ１０の外筒２８の外径ｄ_１（この例では直径６７ｍｍ）と等しい寸法とされている。
一方非凹陥部１８の内径Ｄ_１は、外筒２８の外径ｄ_１よりも小さい寸法、具体的にはここでは直径６５ｍｍの寸法とされている。
尚凹陥部１６の軸方向長Ｌ_２は、相手部材１２全体の軸方向長Ｌ_１の１／２よりも若干小さい寸法とされている。
但しＬ_２の寸法は適宜変更可能である。
【００３５】
一方ゴムブッシュ１０は、図２に示しているように円筒形状をなす内筒２６と、同じく円筒形状をなす外筒２８と、それらの間に配置されて内筒２６及び外筒２８を弾性的に連結するゴム弾性体３０とを有している。
本例においてゴム弾性体３０は内筒２６及び外筒２８に対して一体に加硫接着されている。
ここで内筒２６は金属製とされ、また外筒２８は樹脂製とされている。
尚、内筒２６については剛性の樹脂を用いることも可能である。
またゴム弾性体３０には、図２（Ａ）に示しているように一対の空所（すぐり）３２が軸方向に沿って形成されている。
【００３６】
図２（Ｂ）に示しているように、外筒２８には上記相手部材１２における凹陥部１６とは反対側の軸方向端部に鍔部３３が一体に設けられている。
この鍔部３３の裏面（図２（Ｂ）中右面）は、相手部材１２における軸端面、即ち第２の係合面２２（これは同時に第３の係合面２４ともなっている）に対して軸方向に重合する重合面となるもので、この例ではこの重合面が第２の被係合面３４を成している。
【００３７】
本例において、鍔部３３は周方向に沿って肉厚が変化しており、その第２の被係合面３４が、軸直角方向に対し相手部材１２における第３の係合面２４と同じ角度θで傾斜する傾斜面を成しており、かかる第２の被係合面３４が、同時に回止め用の第３の被係合面３６を成している。
【００３８】
ここでゴムブッシュ１０は外筒２８の軸方向長、詳しくは鍔部３３を除いた部分の軸方向長ｌ_１が、相手部材１２の軸方向長Ｌ_１とほぼ同等とされている。
【００３９】
尚本例において、外筒２８を構成する樹脂としては各種のものを用いることができる。
詳しくは、かかる外筒２８の構成樹脂として熱可塑性樹脂や熱硬化性樹脂等を用いることができ、その中でも振動入力に対する耐衝撃強度や外筒２８としての成形性に優れる熱可塑性樹脂が好適に用いられる。
【００４０】
また熱可塑性樹脂材料としてはポリアミド（芳香族ポリアミドや変性ポリアミドを含む），ポリエステル（変性ポリエステルを含む），ポリプロピレン，ポリカーボネート，ポリアセタール，ポリフェニレンサルファイド，変性ポリフェニレンエーテル等があり、その中でも強度や充填材による補強効果，コストのバランスに優れるポリアミドが好適に用いられる。
【００４１】
またそのような樹脂材料を補強するために樹脂材料に配合ないしは混合される充填材としてガラス繊維，炭素繊維，アラミド繊維，ボロン繊維，アルミナ繊維，金属繊維，炭化珪素繊維，ガラスビーズ，ウィスカー，ワラスナイト，カオリナイト，タルク，マイカ，カーボンナノチューブ他、珪酸マグネシウム若しくは珪酸アルミニウムの層で構成される層状フィロ珪酸塩、例えばモンモリロナイト，ヘクトライト，バーミキュライト，ハロサイト等があるが、その中でも補強効果の高さやコストの点からガラス繊維が好適に用いられる。
また使用部位によっては充填材のない非強化樹脂材料も用いることができる。本例の外筒２８の樹脂材料は、ポリアミド６６（ＰＡ６６）に充填材としてガラス繊維３０％を混合したものを用いている。
【００４２】
本例の筒形防振装置では、図４に示すようにしてゴムブッシュ１０を鍔部３３とは反対側の軸方向端から相手部材１２内部に圧入して組み付け、ゴムブッシュ１０を相手部材１２にて嵌合状態に保持させるようにする。
このとき、樹脂製の外筒２８は弾性変形を伴って縮径しつつ、その外面において相手部材１２の内部に圧入される。
そして圧入後、外筒２８における相手部材１２の凹陥部１６に対向して位置する部分が弾性復元力によって拡径し、凹陥部１６内に部分的に入り込んだ状態となって、外筒２８の外面形状が、相手部材１２の内面形状に倣った段付形状に変形する。
【００４３】
詳しくは、図１において凹陥部１６に対応した部分が大径部３８、非凹陥部１８に対応した部分が小径部４０を成す段付形状に変形し、そしてその変形により生じた外筒２８における段付面が第１の被係合面４２として、相手部材１２側の第１の係合面２０に対し軸方向に、即ち図中左向きに係合した状態となる。
本例において、これら相手部材１２側の第１の係合面２０と外筒２８における第１の被係合面４２とは第１の係合部４４を構成している。
【００４４】
この状態においてゴムブッシュ１０はまた、外筒２８の第２の被係合面３４及びこの第２の被係合面３４全体に亘って形成された第３の被係合面３６、具体的には鍔部３３の裏面の重合面が、相手部材１２の第２の係合面２２及び第２の係合面２２全体に亘って形成された第３の係合面２４に対し同時に係合した状態となる。
ここにおいてゴムブッシュ１０は、相手部材１２に対し図の右方向及び左方向の何れの方向、即ち軸方向の一方向と他方向との両方向に抜止めされた状態となる。
【００４５】
本例ではまた、軸直角方向に対して傾斜した第３の係合面２４と被係合面３６とが周方向に係合することで、相手部材１２に対するゴムブッシュ１０の回転が防止される。
ここで本例では、図１に示しているようにこれら第３の係合面２４及び被係合面３６が第３の係合部４８を成し、また第２の係合面２２及び被係合面３４が第２の係合部４６を成している。
【００４６】
かかる本例の筒形防振装置によれば、圧入後の外筒２８を相手部材１２に対し軸方向の一方向にも、またこれとは反対向きの他方向にも良好に抜止めすることができる。
また本例では、周方向に係合して回止めをなす第３の係合部４８が第２の係合部４６全体に亘って形成してあるため、軸方向の抜けと併せてゴムブッシュ１０を回転方向にも移動阻止することができる。
【００４７】
また本例は、第１の係合部４４において相手部材１２の内面と外筒２８の外面とを係合させるものであり、従って図１３に示す従来の筒形防振装置のように、係合部を相手部材より軸方向外側に突き出した部分に設けることによって、その係合部が外気に曝されて劣化し、また飛び石等が当って割れを生じるなどの問題を回避することができる。
また第１の係合部４４を設けることによって、それだけ外筒２８即ちゴムブッシュ１０が軸方向に長くなってしまうといった問題も解決することができる。
【００４８】
次に図５〜図８は本発明の他の実施例を示している。
図７に示しているように、この例では相手部材１２の段付面から成る第１の係合面２０全体を、図８に示しているように軸直角方向に対し角度θで傾斜した傾斜面となし、かかる第１の係合面２０を全体的に第３の係合面２４として形成する一方、軸端面の第２の係合面２２を軸直角方向の面と成している。
またこれに対応して、図６に示しているようにゴムブッシュ１０における鍔部３３の裏面、即ち重合面である第２の被係合面３４を、相手部材１２の第２の係合面２２に対応して軸直角方向の面と成してある。
【００４９】
本例においては、図８に示しているようにゴムブッシュ１０を相手部材１２に圧入することによって生ずる段付面から成る第１の被係合面４２が、図５に示すように相手部材１２に形成した第１の係合面２０に対応した傾斜形状、即ち軸直角方向に対し角度θで傾斜した傾斜形状の面となり、かかる第１の被係合面４２全体に亘って第３の被係合面３６が形成された状態となる。
そして外筒２８における第３の被係合面３６と、相手部材１２における第３の係合面２４との周方向の係合作用に基づいて、ゴムブッシュ１０が相手部材１２に対し回転防止される。
【００５０】
即ち上記の第１の実施例では、第３の係合面２４及び被係合面３６が、それぞれ第２の係合面２２及び被係合面３４全体に亘って形成されていたが、この例ではそれら第３の係合面２４及び被係合面３６が、第１の係合面２０及び被係合面４２全体に亘ってそれぞれ形成されている。
尚他の点については上記第１の実施例と同様である。
【００５１】
かかる本例の筒形防振装置においても、圧入後の外筒２８を相手部材１２に対し軸方向の一方向にも、またこれとは反対向きの他方向にも良好に抜止めすることができ、また周方向に係合して回止めをなす第３の係合部４８が第１の係合部４４に形成してあるため、軸方向の抜けと併せてゴムブッシュ１０を回転方向にも移動阻止することができる。
【００５２】
次に図９〜図１２は本発明の更に他の実施例を示している。
この例は、第２の実施例において、図１１に示しているように相手部材１２の内面に第１の凹陥部１６と併せて、これとは反対の軸方向端部に第２の凹陥部５２を設けた例である。
この例では、第２の凹陥部５２と非凹陥部１８との間に生ずる段付面を、第２の係合面２２と成している。ここで第２の係合面２２は軸直角方向の面となっている。
一方、図１０に示しているようにゴムブッシュ１０は外筒２８が鍔部３３を有しない鍔無しのゴムブッシュ１０として構成されている。
【００５３】
この例の場合、図１２に示しているようにゴムブッシュ１０を相手部材１２内部に圧入すると、外筒２８が相手部材１２の内面の段付形状に倣った形状に弾性変形して、図９に示しているように第２の凹陥部５２に対応する部分が第２の大径部５６となり、この第２の大径部５６と小径部４０との境界部に段付面が生じる。
本例ではこの段付面が第２の被係合面３４を成し、この第２の被係合面３４が第２の係合面２２に対し軸方向に、詳しくは図９中右向きに係合する。
【００５４】
本例においても、ゴムブッシュ１０は相手部材１２に圧入された後において軸方向の一方向にもまた他方向にも抜止めされると同時に、回転方向にも移動阻止される。
【００５５】
また本例によれば、ゴムブッシュ１０として軸方向端部に鍔部３３を有しないものを用いることができるので、筒形防振装置におけるゴムブッシュ１０の形状を単純化でき、ゴムブッシュ１０に要するコストを低減することができるとともに、相手部材１２に対してゴムブッシュ１０を圧入する際の方向性が制約されなくなり圧入作業性も良好となる。
【００５６】
以上本発明の実施例を詳述したがこれはあくまで一例示である。
例えば本発明においては第３の係合面及び被係合面を周方向の段付面となしたり、或いは周方向に凹凸形状となす面と成したり、更には傾斜形状ではなく湾曲形状の面となしたりすることも可能である。
【００５７】
また本発明は自動車のトーションビーム式リヤサスペンションにおける筒形防振装置以外の各種筒形防振装置に適用することが可能である等、その趣旨を逸脱しない範囲において様々な変更を加えた形態で構成可能である。
【図面の簡単な説明】
【図１】本発明の一実施例である筒形防振装置を、相手部材にゴムブッシュを組み付けた状態で示す図である。
【図２】同実施例におけるゴムブッシュの単品図である。
（Ａ）：（Ｂ）の左側面図である。
（Ｂ）：（Ａ）のＢ−Ｂ断面図である。
【図３】同実施例における相手部材の単品図である。
【図４】同実施例における筒形防振装置の組付方法の説明図である。
【図５】本発明の他の実施例の筒形防振装置を、相手部材にゴムブッシュを組み付けた状態で示す図である。
【図６】同実施例におけるゴムブッシュの単品図である。
（Ａ）：（Ｂ）の左側面図である。
（Ｂ）：（Ａ）のＢ−Ｂ断面図である。
【図７】同実施例における相手部材の単品図である。
【図８】同実施例における筒形防振装置の組付方法の説明図である。
【図９】本発明の更に他の実施例の筒形防振装置を、相手部材にゴムブッシュを組み付けた状態で示す図である。
【図１０】同実施例におけるゴムブッシュの単品図である。
（Ａ）：（Ｂ）の左側面図である。
（Ｂ）：（Ａ）のＢ−Ｂ断面図である。
【図１１】同実施例における相手部材の単品図である。
【図１２】同実施例における筒形防振装置の組付方法の説明図である。
【図１３】従来の筒形防振装置の一例を示す図である。
【符号の説明】
１０ゴムブッシュ
１２相手部材
１６凹陥部（第１の凹陥部）
１８非凹陥部
２０第１の係合面
２２第２の係合面
２４第３の係合面
２６内筒
２８外筒
３０ゴム弾性体
３３鍔部
３４第２の被係合面
３６第３の被係合面
４２第１の被係合面
４４第１の係合部
４６第２の係合部
４８第３の係合部
５２凹陥部（第２の凹陥部）[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a cylindrical vibration isolator in which a rubber bush is press-fitted into a cylindrical counterpart member and held in a fitted state, and more particularly to a rubber bush whose outer cylinder is made of resin.
[0002]
[Prior art]
Conventionally, a rigid outer cylinder and an inner cylinder, and a rubber bush having a rubber elastic body disposed between the outer cylinder and the inner cylinder, are pressed into a cylindrical rigid mating member on the outer surface of the outer cylinder, 2. Description of the Related Art Cylindrical vibration isolators that hold a rubber bush in a fitted state with a mating member are widely used as a suspension bush such as a trailing arm bush or a torque rod bush of an automobile, an engine mount, or the like.
[0003]
In this type of cylindrical vibration isolator, conventionally, the outer cylinder, the inner cylinder, and the mating member of the rubber bush are all made of metal, and when the outer cylinder of the rubber bush is pressed into the mating member with a predetermined interference, the outer cylinder is formed. The rubber bush is prevented from coming off the mating member based on the strong frictional force generated between the outer surface and the inner surface of the mating member.
[0004]
By the way, in recent years, it has been studied to convert the outer cylinder of the rubber bush to resin. In this case, the elastic restoring force of the outer cylinder made of resin is reduced by stress relaxation, and furthermore, the stress is greatly affected by thermal influence. However, even if press-fitting is performed with a predetermined interference at the initial stage, there is a problem that the elastic restoring force of the outer cylinder with respect to the mating member is reduced due to a change over time, and the pulling force is reduced.
[0005]
An example of a countermeasure for this problem is disclosed in Patent Document 1 below.
FIG. 13 shows a specific example thereof. In the figure, reference numeral 200 denotes a rubber bush, which is a metal inner cylinder 202, a rubber elastic body 204 integrally fixed to the outer peripheral surface thereof, and a resin elastic material integrally fixed to the outer peripheral surface of the rubber elastic body 204. And an outer cylinder 206.
A mating member 208 is a metal cylindrical member. The rubber bush 200 is pressed into the mating member 208 and held in a fitted state.
[0006]
The resin outer cylinder 206 has a flange 210 at an axial end (lower end in the figure), and the flange 210 contacts the shaft end surface of the mating member 208 in the upward direction in FIG. The rubber bush 200 is prevented from coming off.
The outer cylinder 206 has a partially thick engagement provided with inclined surfaces 214 and 216 which are inclined in opposite directions to each other at an axial end opposite to the outer cylinder 206 and at a portion protruding in the axial direction from the mating member 208. After the rubber bush 200 is pressed into the mating member 208, the engaging portion 218 is engaged with the shaft end surface of the mating member 208, specifically, the shaft end surface opposite to the flange 210. Accordingly, the rubber bush 200 is prevented from falling off from the partner member 208 in the downward direction in FIG.
[0007]
[Patent Document 1]
Japanese Utility Model Application Laid-Open No. 5-77637 [0008]
[Problems to be solved by the invention]
However, in the device disclosed in Patent Document 1, the rubber bush 200 is not particularly stopped from rotating with respect to the mating member 208, and the elastic bushing 200 made of the resin of the rubber bush 200 pressed into the mating member 208 is restored. When the force is reduced due to the stress relaxation, there is a possibility that the rubber bush 200 relatively rotates with respect to the mating member 208.
[0009]
In the case of the cylindrical vibration isolator shown in FIG. 13, a part of the outer cylinder 206, specifically, a part of the engaging portion 218, protrudes from the partner member 208 in the axial direction, is exposed to the outside, and is exposed to the outside air. In addition to the problem that the material is liable to be deteriorated, there is a problem that a stepping stone or the like hits an exposed portion protruding from the partner member 208 and is liable to be cracked.
[0010]
Further, in the case of this cylindrical vibration isolator, the axial length of the rubber bush 200, in particular, the axial length of the portion excluding the flange 210 must necessarily be longer than the mating member 208, and the shape is limited. Have problems.
[0011]
[Means for Solving the Problems]
The cylindrical vibration isolator of the present invention has been devised to solve such a problem.
According to the first aspect, a rubber bush having a resin outer cylinder, an inner cylinder, and a rubber elastic body disposed between the outer cylinder and the inner cylinder is formed in a cylindrical shape on the outer surface of the outer cylinder. A cylindrical vibration isolator, which is press-fitted into a rigid mating member and holds the rubber bush in a fitted state with the mating member, wherein the rubber bush is recessed radially outward on the inner surface of the mating member. And a first engagement surface for axial engagement consisting of a stepped surface is formed at a boundary between the concave portion and the non-recess portion, while the outer cylinder is formed. Before press-fitting into the mating member, the outer surface of the outer cylinder is made larger in diameter than the non-recessed portion, and is press-fitted into the mating member while reducing the diameter of the outer cylinder by utilizing the elasticity of resin. The outer shape of the cylinder is elastically deformed into a stepped shape following the inner shape of the mating member, and the outer cylinder has a shape corresponding to the first engagement surface. A first engaged surface comprising a stepped surface is formed to form a first engaging portion together with the first engaging surface, and the first engaging surface and the first engaged surface are formed. At the same time in the axial direction, the mating member and the outer cylinder at the other position in the axial direction are opposite in the axial direction to the direction of engagement of the first engagement surface and the first engaged surface. Forming a second engaging surface and a second engaged surface to be engaged with each other to form a second engaging portion, and the first engaging portion and the second engaging portion A third engaging surface and a third engaged surface that are circumferentially engaged to form a detent are formed on at least one of the engaging surface and the engaged surface, thereby forming a third engaging surface. It is characterized by forming a joint.
[0012]
According to a second aspect, in the first aspect, the engagement surface and the engaged surface on the side of the first engagement portion and the second engagement portion on which the third engagement portion is not formed are formed. , Formed as a plane perpendicular to the axis.
[0013]
According to a third aspect of the present invention, in any one of the first and second aspects, the shaft end surface of the mating member and the overlapped surface of the flange portion of the outer cylinder in the flanged rubber bush that overlaps the shaft end surface are formed by the second surface. An engagement surface and an engaged surface are provided.
[0014]
According to a fourth aspect of the present invention, in the third aspect, the second engagement surface and the engaged surface are formed as inclined surfaces inclined with respect to the direction perpendicular to the axis, and the second engagement surface and the engaged surface are formed. The third engaging surface for locking and the engaged surface are formed over the entire surface.
[0015]
According to a fifth aspect of the present invention, in the third aspect, the first engagement surface and the engaged surface are formed as inclined surfaces inclined with respect to a direction perpendicular to the axis, and the first engagement surface and the engaged surface are formed. The third engaging surface and the engaged surface for the rotation are formed over the entire surface, while the second engaging surface and the engaged surface are surfaces perpendicular to the axis. And
[0016]
According to a sixth aspect of the present invention, in one of the first and second aspects, a first concave portion is provided at one end in the axial direction of the counterpart member, and a second concave portion is provided at the other end. A first engaging surface and a second engaging surface which are opposite to each other in the axial direction are formed at the boundary between the non-recessed portion and the axially intermediate portion, and these are formed on the outer cylinder. Corresponding to the first engaged surface and the second engaged surface, and the engagement surface and the engagement surface of at least one of the first engagement portion and the second engagement portion. The third engaging surface and the engaged surface are formed on the engaging surface.
[0017]
According to a seventh aspect, in the sixth aspect, an inclined surface in which an engaging surface and an engaged surface of at least one of the first engaging portion and the second engaging portion are inclined with respect to a direction perpendicular to an axis. And the inclined surface is the third engagement surface and the engaged surface.
[0018]
An eighth aspect of the present invention is characterized in that, in any one of the first to seventh aspects, the outer surface of the outer cylinder has a substantially axially straight shape before being pressed into the counterpart member. .
[0019]
According to a ninth aspect of the present invention, in any one of the first, second, and sixth to eighth aspects, the rubber bush has no flange having no flange at an axial end of the outer cylinder.
[0020]
[Action and effect of the invention]
As described above, the present invention press-fits a resin outer cylinder in a rubber bush to a mating member, and elastically deforms the outer surface shape of the outer cylinder into a stepped shape that follows the inner surface shape of the mating member. A first engaged surface, which is axially engaged with a first engaging surface formed by a stepped surface of a mating member, is formed in the outer cylinder, and the mating member is formed at another position in the axial direction with the first mating surface. And the outer cylinder are formed with a second engagement surface and an engaged surface that engage in opposite directions in the axial direction with respect to the direction of engagement of the first engagement surface and the engaged surface, and An engagement surface in at least one of the first engagement portion including the first engagement surface and the engaged surface, and a second engagement portion including the second engagement surface and the engaged surface; On the engaged surface, a third engaging surface and an engaged surface which are circumferentially engaged to form a detent are formed.
[0021]
According to the present invention, it is possible to prevent the press-fitted outer cylinder from coming off in the axial direction with respect to the mating member and in the other direction opposite thereto.
In the present invention, the third engaging portion that engages in the circumferential direction to form a detent is formed on at least one of the first engaging portion and the second engaging portion. The rubber bush can also be prevented from moving in the rotation direction in conjunction with the drop in the direction.
[0022]
Further, in the present invention, the inner surface of the mating member and the outer surface of the outer cylinder are engaged with each other at the first engaging portion. Therefore, as in the cylindrical vibration isolator shown in FIG. By providing the portion protruding further outward in the axial direction, it is possible to avoid the problem that the engaging portion is exposed to the outside air, deteriorates, and a stepping stone or the like causes cracking.
Further, by providing at least the first engagement portion, it is possible to solve the problem that the outer cylinder, that is, the rubber bush, becomes longer in the axial direction.
[0023]
Here, the engaging surface and the engaged surface of the first engaging portion and the second engaging portion on which the third engaging portion is not formed should be surfaces perpendicular to the axis. (Claim 2).
[0024]
Further, in the present invention, the shaft end surface of the mating member and the overlapped surface of the flange portion of the outer cylinder of the rubber bush that overlaps with the shaft end surface can be the second engagement surface and the engaged surface. .
[0025]
In this case, the second engagement surface and the engaged surface, that is, the overlapping surface of the shaft end surface of the mating member and the flange portion of the rubber bush are formed as inclined surfaces inclined with respect to the direction perpendicular to the axis, and these second engagement surfaces are formed. The third engaging surface and the engaged surface can be formed over the entire mating surface and the engaged surface, that is, the entire overlapping surface of the shaft end surface of the mating member and the flange portion of the rubber bush. 4).
[0026]
Alternatively, according to claim 5, the first engaging surface and the engaged surface formed of the stepped surface are inclined surfaces, and the third engaging surface and the engaged surface for preventing rotation are entirely formed. On the other hand, the second engagement surface and the engaged surface can be surfaces perpendicular to the axis.
[0027]
On the other hand, according to a sixth aspect of the present invention, a first concave portion is provided at one end in the axial direction of a mating member, and a second concave portion is provided at the other end. Forming a mating surface and a second engaging surface, and forming a first engaged surface and a second engaged surface corresponding to the outer cylinder of the rubber bush and engaging them with each other; While preventing the rubber bush from being pulled out of the mating member in one direction and the other direction in the axial direction, the engagement surface and the engagement surface of at least one of the first engagement portion and the second engagement portion are The third engagement surface and the engaged surface for rotation prevention are formed, and in this case, the rubber bush can be properly prevented from being removed in both the axial direction and the other direction. At the same time, the rotational movement of the rubber bush with respect to the mating member can be prevented.
[0028]
According to the sixth aspect, it is possible to use a rubber bush whose outer cylinder does not have a flange at an axial end portion (claim 9).
Thus, if a rubber bush without such a flange can be used, the shape of the rubber bush in the cylindrical vibration isolator can be simplified, the cost required for the rubber bush can be reduced, and the mating member can be used. On the other hand, the direction in press-fitting the rubber bush is not restricted, and the press-fitting workability is improved.
[0029]
In the sixth aspect, the third engaging surface and the engaged surface may be stepped surfaces in the circumferential direction (this point is the same in the first to fifth aspects). The engaging surface and the engaged surface in at least one of the first engaging portion and the second engaging portion are inclined with respect to the direction perpendicular to the axis, and the third engaging surface and the engaged surface (Claim 7).
[0030]
Further, in the present invention, the outer surface of the outer cylinder can be formed in a substantially axially straight shape before being pressed into the mating member (claim 8).
[0031]
【Example】
Next, embodiments of the present invention will be described in detail with reference to the drawings.
This is an example of a cylindrical vibration isolator used for connecting a trailing arm and a vehicle body in a torsion beam type rear suspension of an automobile. FIG. 2 shows a rubber bush 10 and FIG. 3 shows a rubber bush 10 shown in FIG. FIG. 1 shows a state where the rubber bush 10 of FIG. 2 is press-fitted into the mating member 12 of FIG. 3 and assembled.
In FIG. 1, reference numeral 14 denotes an arm extending from the mating member 12.
[0032]
As shown in FIG. 3, the mating member 12 has a cylindrical shape corresponding to the rubber bush 10 as a whole.
Here, the mating member 12 is entirely made of metal.
On the inner surface of the mating member 12, an annular concave portion (first concave portion) 16 that is concave outward in the radial direction is provided at one end portion in the axial direction (the right end portion in FIG. 3B). A stepped surface is formed at the boundary between the recess 16 and the non-recess 18.
Here recess 16 is axially length as shown in FIG. 4 is a L _2.
[0033]
In this example, this stepped surface forms the first engagement surface 20. Here, the first engagement surface 20 formed of a stepped surface is a surface in a direction perpendicular to the axis.
In the present example, the shaft end face on the opposite side to the provision of the recess 16 is a second engagement face 22.
As shown in FIG. 4, the second engaging surface 22 forms an inclined surface which is entirely inclined at an angle θ with respect to the direction perpendicular to the axis.
That is, in this example, the entire second engagement surface 22 simultaneously constitutes the third engagement surface 24 for stopping rotation.
[0034]
Here, the inner diameter D ₂ (see FIG. 4) of the concave portion 16 is set to be equal to the outer diameter d ₁ (67 mm in this example) of the outer cylinder 28 of the rubber bush 10 before press fitting.
Meanwhile the inner diameter D ₁ of the non-recessed portion 18, smaller than the outer diameter d ₁ of the outer tube 28, here specifically is sized with a diameter 65 mm.
Note axial length L ₂ of the recessed portion 16 is slightly smaller than 1/2 of the mating member 12 as a whole in the axial direction length L _1.
However the dimensions of the L ₂ can be appropriately changed.
[0035]
On the other hand, the rubber bush 10 has an inner cylinder 26 having a cylindrical shape as shown in FIG. 2, an outer cylinder 28 also having a cylindrical shape, and an inner cylinder 26 and an outer cylinder 28 which are disposed therebetween to elastically couple the inner cylinder 26 and the outer cylinder 28. And a rubber elastic body 30 connected to the rubber elastic body 30.
In this embodiment, the rubber elastic body 30 is integrally vulcanized and bonded to the inner cylinder 26 and the outer cylinder 28.
Here, the inner cylinder 26 is made of metal, and the outer cylinder 28 is made of resin.
Note that a rigid resin can be used for the inner cylinder 26.
As shown in FIG. 2A, a pair of cavities (curves) 32 are formed in the rubber elastic body 30 along the axial direction.
[0036]
As shown in FIG. 2 (B), the outer cylinder 28 is integrally provided with a flange 33 at an axial end of the mating member 12 opposite to the recess 16.
The back surface (the right surface in FIG. 2B) of the flange portion 33 is opposed to the shaft end surface of the mating member 12, that is, the second engagement surface 22 (which also serves as the third engagement surface 24 at the same time). The overlapping surface forms an overlapping surface in the axial direction. In this example, the overlapping surface forms the second engaged surface 34.
[0037]
In this example, the thickness of the flange portion 33 changes along the circumferential direction, and the second engaged surface 34 is the same as the third engaging surface 24 of the mating member 12 in the direction perpendicular to the axis. The second engaged surface 34 constitutes a third engaged surface 36 for stopping rotation at the same time.
[0038]
Here, the axial length l ₁ of the rubber bush 10 in the axial direction of the outer cylinder 28, specifically, the axial length l ₁ of a portion excluding the flange 33 is substantially equal to the axial length L ₁ of the mating member 12.
[0039]
In this example, various resins can be used as the resin constituting the outer cylinder 28.
Specifically, a thermoplastic resin, a thermosetting resin, or the like can be used as a constituent resin of the outer cylinder 28, and among them, a thermoplastic resin having excellent impact resistance against vibration input and excellent moldability as the outer cylinder 28 is preferable. Used.
[0040]
The thermoplastic resin materials include polyamide (including aromatic polyamide and modified polyamide), polyester (including modified polyester), polypropylene, polycarbonate, polyacetal, polyphenylene sulfide, and modified polyphenylene ether. A polyamide excellent in balance between the reinforcing effect and the cost is preferably used.
[0041]
Glass fiber, carbon fiber, aramid fiber, boron fiber, alumina fiber, metal fiber, silicon carbide fiber, glass beads, whisker, wollastonite are used as fillers mixed or mixed with the resin material to reinforce such a resin material. , Kaolinite, talc, mica, carbon nanotubes, and other layered phyllosilicates composed of magnesium silicate or aluminum silicate layers, such as montmorillonite, hectorite, vermiculite, and halosite. Glass fiber is preferably used in terms of cost.
Further, a non-reinforced resin material having no filler may be used depending on a use site. The resin material of the outer cylinder 28 of this example is a mixture of polyamide 66 (PA66) and 30% glass fiber as a filler.
[0042]
In the cylindrical vibration isolator of this example, as shown in FIG. 4, the rubber bush 10 is press-fitted into the inside of the mating member 12 from the axial end opposite to the flange portion 33, and is assembled. To keep the fitting state.
At this time, the outer cylinder 28 made of resin is press-fit into the inside of the mating member 12 on its outer surface while reducing its diameter with elastic deformation.
Then, after the press-fitting, the portion of the outer cylinder 28 located opposite to the concave portion 16 of the mating member 12 is expanded in diameter by the elastic restoring force, and partially enters the concave portion 16. The outer shape changes to a stepped shape following the inner shape of the mating member 12.
[0043]
Specifically, in FIG. 1, a portion corresponding to the concave portion 16 is deformed into a stepped shape forming a large-diameter portion 38 and a portion corresponding to the non-recessed portion 18 is formed as a small-diameter portion 40. The stepped surface is engaged with the first engagement surface 20 on the mating member 12 side in the axial direction, that is, in the leftward direction in the drawing, as the first engaged surface 42.
In this example, the first engagement surface 20 on the side of the counterpart member 12 and the first engaged surface 42 of the outer cylinder 28 constitute a first engagement portion 44.
[0044]
In this state, the rubber bush 10 also has a second engaged surface 34 of the outer cylinder 28 and a third engaged surface 36 formed over the entire second engaged surface 34, specifically, The overlapped surface on the back surface of the flange portion 33 was simultaneously engaged with the second engagement surface 22 of the mating member 12 and the third engagement surface 24 formed over the entire second engagement surface 22. State.
Here, the rubber bush 10 is in a state in which the rubber bush 10 is prevented from being pulled out with respect to the counterpart member 12 in either the right direction or the left direction in the drawing, that is, in one direction and the other direction in the axial direction.
[0045]
In this example, the rotation of the rubber bush 10 with respect to the mating member 12 is prevented by the circumferential engagement between the third engaging surface 24 and the engaged surface 36 inclined with respect to the direction perpendicular to the axis. .
Here, in the present example, as shown in FIG. 1, the third engaging surface 24 and the engaged surface 36 form a third engaging portion 48, and the second engaging surface 22 and the The engagement surface 34 forms a second engagement portion 46.
[0046]
According to the cylindrical vibration isolator of this example, the outer cylinder 28 after press-fitting can be prevented from being removed well in one axial direction with respect to the mating member 12 and in the other direction opposite thereto. Can be.
Further, in this example, since the third engaging portion 48 which engages in the circumferential direction to form a detent is formed over the entire second engaging portion 46, the rubber bushing is provided together with the axial removal. 10 can also be prevented from moving in the rotational direction.
[0047]
In this embodiment, the inner surface of the mating member 12 and the outer surface of the outer cylinder 28 are engaged with each other at the first engagement portion 44. Therefore, as in the conventional cylindrical vibration isolator shown in FIG. By providing the joint portion at a portion protruding outward in the axial direction from the mating member, it is possible to avoid a problem that the engaging portion is exposed to the outside air, deteriorates, and a stepping stone or the like causes cracking.
Further, by providing the first engagement portion 44, the problem that the outer cylinder 28, that is, the rubber bush 10, becomes longer in the axial direction can be solved.
[0048]
Next, FIGS. 5 to 8 show another embodiment of the present invention.
As shown in FIG. 7, in this example, the entire first engagement surface 20 formed of the stepped surface of the mating member 12 is inclined at an angle θ with respect to the direction perpendicular to the axis as shown in FIG. The first engagement surface 20 is formed as a third engagement surface 24 as a whole, while the second engagement surface 22 of the shaft end surface is a surface perpendicular to the axis.
Correspondingly, as shown in FIG. 6, the back surface of the flange portion 33 of the rubber bush 10, that is, the second engaged surface 34 which is 22 and a plane perpendicular to the axis.
[0049]
In the present embodiment, as shown in FIG. 8, the first engaged surface 42 formed of a stepped surface formed by press-fitting the rubber bush 10 into the mating member 12 is used as shown in FIG. The first engagement surface 20 has an inclined shape corresponding to the first engagement surface 20, that is, a surface having an inclined shape inclined at an angle θ with respect to the direction perpendicular to the axis. The state where the engagement surface 36 is formed is obtained.
The rubber bush 10 is prevented from rotating with respect to the mating member 12 based on the circumferential engagement between the third engaged surface 36 of the outer cylinder 28 and the third engaging surface 24 of the mating member 12. You.
[0050]
That is, in the first embodiment, the third engaging surface 24 and the engaged surface 36 are formed over the entire second engaging surface 22 and the engaged surface 34, respectively. In the example, the third engagement surface 24 and the engaged surface 36 are formed over the entire first engagement surface 20 and the engaged surface 42, respectively.
The other points are the same as in the first embodiment.
[0051]
In the cylindrical vibration isolator of the present embodiment as well, it is possible to favorably prevent the outer cylinder 28 after press-fitting in the axial direction with respect to the mating member 12 in the axial direction and in the other direction opposite thereto. Also, since the third engagement portion 48 which engages in the circumferential direction to form a detent is formed in the first engagement portion 44, the rubber bush 10 is moved in the rotational direction together with the axial removal. Can also be prevented from moving.
[0052]
9 to 12 show still another embodiment of the present invention.
This example is different from the second embodiment in that, as shown in FIG. 11, the inner surface of the mating member 12 is combined with the first concave portion 16 and the second concave portion is formed at the opposite axial end. This is an example in which 52 is provided.
In this example, the stepped surface generated between the second concave portion 52 and the non-recessed portion 18 is the second engaging surface 22. Here, the second engagement surface 22 is a surface perpendicular to the axis.
On the other hand, as shown in FIG. 10, the rubber bush 10 is configured as a rubber bush 10 without a flange in which the outer cylinder 28 has no flange 33.
[0053]
In the case of this example, when the rubber bush 10 is pressed into the mating member 12 as shown in FIG. 12, the outer cylinder 28 is elastically deformed into a shape following the stepped shape of the inner surface of the mating member 12, and FIG. The portion corresponding to the second concave portion 52 becomes the second large-diameter portion 56, and a stepped surface is formed at the boundary between the second large-diameter portion 56 and the small-diameter portion 40 as shown in FIG.
In this example, this stepped surface constitutes a second engaged surface 34, and the second engaged surface 34 is axially directed to the second engaging surface 22, specifically, to the right in FIG. Engage.
[0054]
Also in this example, after being pressed into the mating member 12, the rubber bush 10 is prevented from being pulled out in one direction or the other direction in the axial direction, and is also prevented from moving in the rotation direction.
[0055]
Further, according to this example, since the rubber bush 10 having no flange 33 at the axial end can be used, the shape of the rubber bush 10 in the cylindrical vibration isolator can be simplified. The required cost can be reduced, and the direction of press-fitting the rubber bush 10 into the mating member 12 is not restricted, and the press-fitting workability is improved.
[0056]
The embodiment of the present invention has been described in detail above, but this is merely an example.
For example, in the present invention, the third engagement surface and the engaged surface are formed as circumferentially stepped surfaces, or are formed as surfaces having irregularities in the circumferential direction. It can also be a face.
[0057]
In addition, the present invention can be applied to various cylindrical vibration isolators other than the cylindrical vibration isolators in the torsion beam type rear suspension of an automobile, and is configured in various modified forms without departing from the gist thereof. It is possible.
[Brief description of the drawings]
FIG. 1 is a view showing a cylindrical vibration isolator according to one embodiment of the present invention in a state in which a rubber bush is assembled to a mating member.
FIG. 2 is a single item diagram of a rubber bush in the embodiment.
(A): It is a left view of (B).
(B): It is BB sectional drawing of (A).
FIG. 3 is a single item diagram of a mating member in the embodiment.
FIG. 4 is an explanatory diagram of an assembling method of the cylindrical vibration isolator in the embodiment.
FIG. 5 is a view showing a cylindrical vibration isolator according to another embodiment of the present invention in a state in which a rubber bush is assembled to a mating member.
FIG. 6 is a single item diagram of the rubber bush in the embodiment.
(A): It is a left view of (B).
(B): It is BB sectional drawing of (A).
FIG. 7 is a single item view of a mating member in the embodiment.
FIG. 8 is an explanatory diagram of a method of assembling the cylindrical vibration isolator in the embodiment.
FIG. 9 is a view showing a cylindrical vibration isolator according to still another embodiment of the present invention in a state where a rubber bush is assembled to a mating member.
FIG. 10 is a single item diagram of the rubber bush in the embodiment.
(A): It is a left view of (B).
(B): It is BB sectional drawing of (A).
FIG. 11 is a single-piece drawing of a mating member in the embodiment.
FIG. 12 is an explanatory diagram of a method of assembling the cylindrical vibration isolator in the embodiment.
FIG. 13 is a diagram showing an example of a conventional cylindrical vibration isolator.
[Explanation of symbols]
10 rubber bush 12 mating member 16 concave portion (first concave portion)
18 Non-recessed part 20 First engaging surface 22 Second engaging surface 24 Third engaging surface 26 Inner cylinder 28 Outer cylinder 30 Rubber elastic body 33 Flange part 34 Second engaged surface 36 Third The engaged surface 42 The first engaged surface 44 The first engaging portion 46 The second engaging portion 48 The third engaging portion 52 A concave portion (a second concave portion)

Claims

A rubber bush having a resin outer cylinder, an inner cylinder, and a rubber elastic body disposed between the outer cylinder and the inner cylinder is pressed into a cylindrical rigid mating member on the outer surface of the outer cylinder. In a cylindrical vibration isolator configured to hold a rubber bush in a fitted state with the mating member,
On the inner surface of the mating member, a recess in the form of being radially outwardly recessed is partially formed in the axial direction, and a boundary between the recess and the non-recess is formed with a stepped surface for axial engagement. While the first engaging surface is formed, the outer surface of the outer cylinder is made larger in diameter than the non-recessed portion in a state before being press-fitted into the mating member, and the outer cylinder is formed by utilizing the elasticity of resin. Pressing into the inside of the mating member while reducing the diameter, elastically deforms the outer surface shape of the outer cylinder into a stepped shape following the inner surface shape of the mating member, and corresponds to the first engagement surface on the outer cylinder. A first engaged surface formed of a stepped surface having a curved shape is formed to form a first engaging portion together with the first engaging surface, and the first engaging surface and the first engaged surface are formed. The mating surface is engaged in the axial direction, and the direction of engagement of the first engaging surface and the first engaged surface with the mating member and the outer cylinder at another position in the axial direction. Form a second engagement surface and a second engaged surface that are engaged in opposite directions in the axial direction, thereby forming a second engagement portion, and the first engagement portion and the second engagement surface. A third engaging surface and a third engaged surface which are circumferentially engaged to form a detent on the engaging surface and the engaged surface of at least one of the two engaging portions; A cylindrical anti-vibration device characterized by comprising a third engaging portion with them.

2. The engagement surface and the engaged surface of the first engagement portion and the second engagement portion on the side where the third engagement portion is not formed, according to claim 1, wherein a surface in a direction perpendicular to an axis is defined. A cylindrical vibration isolator characterized by being formed.

The second engaging surface and the engaged member according to any one of claims 1 and 2, wherein the shaft end surface of the mating member and the overlapping surface of the flange portion of the outer cylinder in the flanged rubber bush that overlaps with the shaft end surface are brought into contact with the second engagement surface. A cylindrical vibration isolator characterized by having a surface.

4. The device according to claim 3, wherein the second engagement surface and the engaged surface are inclined surfaces inclined with respect to the direction perpendicular to the axis, and the rotation is performed over the entire second engagement surface and the engaged surface. A cylindrical vibration isolator, wherein a third engaging surface for engagement and an engaged surface are formed.

4. The device according to claim 3, wherein the first engagement surface and the engaged surface are inclined surfaces inclined with respect to a direction perpendicular to the axis, and the rotation is performed over the entire first engagement surface and the engaged surface. A cylindrical vibration isolator, wherein a third engaging surface and an engaged surface for stopping are formed, and the second engaging surface and the engaged surface are surfaces perpendicular to the axis. .

4. The method according to claim 1, wherein a first concave portion is provided at one end in the axial direction of the mating member, and a second concave portion is provided at the other end. A first engaging surface and a second engaging surface that are opposite to each other in the axial direction are formed at a boundary portion with the recessed portion, and these are formed on the corresponding first cover formed on the outer cylinder. The first engagement portion and the second engagement portion are engaged with the engagement surface and the second engagement surface, and the engagement surface and the engagement surface of at least one of the first engagement portion and the second engagement portion are provided with the second engagement portion. 3. A cylindrical vibration isolator, wherein the engaging surface and the engaged surface of No. 3 are formed.

7. The inclined surface according to claim 6, wherein an engaging surface and an engaged surface of at least one of the first engaging portion and the second engaging portion are inclined with respect to a direction perpendicular to an axis. Are formed as the third engaging surface and the engaged surface.

The cylindrical vibration isolator according to any one of claims 1 to 7, wherein an outer surface of the outer cylinder has a substantially axially straight shape before being pressed into the counterpart member.

The cylindrical vibration isolator according to any one of claims 1, 2, 6 to 8, wherein the rubber bush has no flange without a flange at an axial end of the outer cylinder.