JP4188116B2

JP4188116B2 - Vibration isolator

Info

Publication number: JP4188116B2
Application number: JP2003074146A
Authority: JP
Inventors: 雅英小林
Original assignee: Honda Motor Co Ltd; Yamashita Rubber Co Ltd
Current assignee: Honda Motor Co Ltd; Yamashita Rubber Co Ltd
Priority date: 2003-03-18
Filing date: 2003-03-18
Publication date: 2008-11-26
Anticipated expiration: 2023-03-18
Also published as: JP2004278750A

Description

【０００１】
【発明の属する技術分野】
この発明は、エンジンマウント等に好適な防振装置に係り、特に、ストッパを備えるとともにストッパと防振ゴムとの接触音を低減したものに関する。
【０００２】
【従来の技術】
エンジンマウント等に使用される防振装置は種々の形式のものが公知であり、例えば円筒ブッシュ型エンジンマウントは図８に略図を示すように、内筒１と外筒２の間を防振ゴム３で連結するとともに、外筒２側から内筒１側へ向けてストッパ４を突出させ、内筒１が下方へ向かって過大に変位したときこれをストッパ４で受けるようになっている。
【０００３】
【特許文献１】
特開平７−１６９６４２号公報
【特許文献２】
特開２０００−４６０９７号公報
【０００４】
【発明が解決しようとする課題】
図８において、このエンジンマウントを図の左右方向が車両の前後方向となるように配置した場合において、大振動時に内筒１へ大きな荷重がかかることによって、図の上下方向のみならず、これと略直交するような各種方向へ大きく変位すると、防振ゴム３の一部が仮想線で示すようにストッパ４の上面へ接触して摩擦により異音を発生することがある。
そこでこのようなストッパ４と防振ゴム３の接触による異音の発生低減が望まれており、本願発明はこの要請を実現することを目的とする。
【０００５】
【課題を解決するための手段】
上記課題を解決するため請求項１の発明は、振動源側へ取付けられる第１の取付部材と、振動受け側へ取付けられる第２の取付部材とを防振ゴムで連結した防振装置において、
前記防振ゴムに液室を設け、この液室内へ前記第１の取付部材又は第２の取付部材のいずれか一方側から他方側へ突出するストッパを設けるとともに、
このストッパは頂部である受け止め面とこの受け止め面の周囲に設けられる側面とを備えた略台形状をなし、この受け止め面と側面とのコーナー部を跨いで受け止め面から側面へ形成された複数の溝を設け、これら複数の溝によりストッパの表面のうち少なくとも前記コーナー部を含む前記防振ゴムと接触する部分に摩擦低減部を形成し、前記コーナー部に前記防振ゴムが接触したとき、コーナー部を跨ぐ溝により作動液体を逃がすようにしたことを特徴とする。
【０００６】
請求項２の発明は上記請求項１において、前記摩擦低減部が凹凸による接触面積低減構造によることを特徴とする。
【０００７】
請求項３の発明は上記請求項１又は２において、前記ストッパは頂部である受け止め面と側面とを備えた略台形状をなし、この受け止め面と側面とのコーナー部に前記摩擦低減部を形成したことを特徴とする。
【０００８】
請求項４の発明は上記請求項３において、前記摩擦低減部は、前記コーナー部を跨いで形成された複数の溝からなることを特徴とする。
【０００９】
請求項５の発明は上記請求項１において、前記第１の取付部材が内筒であり、前記第２の取付部材がこの内筒の周囲を囲む外筒であり、これらによって全体が円筒型ブッシュをなすとともに、前記ストッパが前記外筒側から前記内筒側へ突出していることを特徴とする。
【００１０】
【発明の効果】
請求項１によれば、ストッパに摩擦低減部を設けたので、防振ゴムがストッパへ接触するとき、摩擦が低減されて異音の発生を低減させることができる。
【００１１】
請求項２によれば、ストッパに凹凸からなる接触面積低減構造を設けたので、摩擦低減部を容易に形成できる。
【００１２】
請求項３によれば、ストッパを略台形とし、そのコーナー部に摩擦低減部を設けたので、防振ゴムが最初に接触するコーナー部において接触時の摩擦を低減して効率的に異音の発生を低減できる。
【００１３】
請求項４によれば、請求項３の摩擦低減部を、コーナー部を跨ぐ溝によって構成したので、コーナー部へ簡単に摩擦低減部を設けることができる。
【００１４】
請求項５によれば、ストッパを設けた円筒型ブッシュマウントに対して容易に適用できる。
【００１５】
【発明の実施の形態】
以下、図面に基づいて自動車用円筒ブッシュ型エンジンマウントに適用された一実施例を説明する。図１はこのエンジンマウントの正面図、図２は図１の２−２線断面図、図３は図２の３−３線断面図、図４はストッパの正面図、図５はストッパの上面図、図６は図５の６−６線断面図、図７は図５の７−７線断面図である。
【００１６】
まず図１〜３において、このエンジンマウント１０は、内筒１１、その周囲を囲む外筒１２及びこれらの間を連結する防振ゴム１３を備える。内筒１１は金属等の適宜剛性材料よりなるパイプ状部材であり、この中空部に通されたボルト等の図示しない連結部材により振動源である図示しないエンジンへ取付けられる。内筒１１は第１の取付部材をなす。
【００１７】
外筒１２は金属等の適宜剛性材料よりなる円筒状部材であり、偏心位置に外筒１２を内包するとともに、ブラケット１５により図示しない振動受け側の車体へ取付けられる。外筒１２は第２の取付部材をなす。
【００１８】
本実施例においては、図１に示す状態にて上下方向を車体の上下方向とし、この方向をエンジンマウント１０に対する主たる振動の入力方向Ｚとする。また、左右方向を車体の前後方向Ｘとし、仮に図の左方を車体前方、右方を車体後方とする。なお、内筒１１の軸方向をＹ方向とする。Ｙ方向は車体の左右方向であり、仮に図２の左方を車体左側、右方を車体右側とする。
【００１９】
防振ゴム１３は天然又は合成等公知の適宜ゴム様材料よりなり、内筒１１を外筒１２に対して浮動支持し、所定のバネ弾性を発揮するようになっている。内筒１１の上方には、内筒１１の軸方向へ貫通するすぐり１６が形成され、このすぐり１６を挟んで内筒１１に対面する外筒１２の内面にダイヤフラム１７が形成されている。
【００２０】
すぐり１６より下方は左右の側壁１８をなし、図２に示すように、この側壁１８間に主液室２０が形成され、ここに非圧縮性の公知作動液体が封入されている。主液室２０内には図２のＹ軸方向断面にて略台形をなすストッパ１４が外筒１２から内筒１１側へ突出して設けられ、内筒１１が過大に下方変位したとき、これを受け止めるようになっている。
【００２１】
ダイヤフラム１７は、すぐり１６より上方の外筒１２内面との間に副液室２１を区画し、すぐり１６内へ伸縮して副液室２１の体積変化を補償するようになっており、防振ゴム１３と連続一体に形成される可撓性部材であるが、エンジンマウント１０を構成するゴムバネとしては無視できる程度に小さなバネ弾性が与えられている。
【００２２】
副液室２１はオリフィス通路２２を介して主液室２０と連通し、内筒１１の上下動等に伴う主液室２０の容積変化により液体が主液室２０と副液室２１の間を流動することにより、オリフィス通路２２において所定の振動周波数で液柱共振するようになっている。このオリフィス通路２２は低周波数域に共振点を有する公知の減衰オリフィス通路である。
【００２３】
図３に明らかなように、オリフィス通路２２はストッパ１４の外周部に形成された溝２３及び防振ゴム１３の外周部に形成された溝２４により外筒１２の内周面との間に形成される。
【００２４】
防振ゴム１３は図３に示す内筒１１の軸線と直交する断面内において内筒１１から前後へ延出するアーム部２５を備える。このアーム部２５の上面はすぐり１６に臨み、下面は主液室２０に臨む。また、アーム部２５の左右両端部は側壁１８へ連続し、アーム部２５と側壁１８により主液室２０の弾性の壁部を形成している。
【００２５】
アーム部２５は主としてせん断方向の弾性変形により荷重を受ける防振ゴムとしての主体的部分であり、その図３における径方向外周側端部は外周部２６に連続し、この外周部２６にてダイヤフラム１７へ連続している。防振ゴム１３は、ダイヤフラム１７，側壁１８及びアーム部２５並びに外周部２６が連続一体に形成されている。溝２４は外周部２６の外周部に形成される。
【００２６】
また、内筒１１の周囲には、アーム部２５の径方向内周端側部分から連続する被覆部２７が形成され、その下部側は主液室２０内へ突出する上側ストッパ２８となっている。
【００２７】
ストッパ１４は主液室２０内にて、図示の初期状態のとき並びに側壁１８と措定の間隔を形成するように配置される。但し、エンジン側から内筒１１へ大荷重の入力があり、内筒１１が下方変位して大きく沈み込んだときは、ストッパ１４が上側ストッパ２８へ接触してこれを受け止める。また、内筒１１の軸線方向へ大きく変位して側壁１８が図２の仮想線のように左右方向へ大きく変形するときや、前進から後退へギヤチェンジしたときのようにアーム部２５の一方が図４の仮想線のように沈み込み変形すると、側壁１８やアーム部２５がストッパ１４へ接触するようになっている。
【００２８】
図４〜図７に示すように、ストッパ１４は６−６ナイロン等の適当な剛性のある材料からなり、主液室内へ突出するストッパ本体部３０と、これと一体に形成されて外筒１２の内面に沿う円弧状外周部３１とを備える。ストッパ本体部３０の上面はＺ方向に直交するほぼ平坦で内筒１１を受け止めるための受け止め面３２をなし、さらにＺ方向に右平行な左右側面３３を備える。但し前後側面３４は略４５°程度の比較的緩やかな斜面になっている（図４）。
【００２９】
図４及び５に示すように、受け止め面３２と左右側面３３との長手方向に延びる左右両コーナー部３５（図７参照）を跨いで、溝３６が受け止め面３２から左右側面３３へ回り込むように溝３６が形成されている。この溝３６はコーナー部３５に沿って長手方向へ複数かつ適当数がストッパ１４の成形時に同時一体に形成するかまたは後から機械加工で形成され、上面中央部は非連続になっている。但し、連続させることは任意である。この溝３６によりストッパ１４の受け止め面３２が凹凸になって接触面積低減構造をなしている。
【００３０】
なお、ストッパ本体部３０は中央の柱部３７を挟んで前後に肉抜穴３８が左右へ貫通形成されている。また、円弧状外周部３１の周方向両端には図５において明らかなように、幅方向中央に切り欠き３９、４０が形成され、前側の切り欠き３９よりも後側の切り欠き４０の方が大きくなっている。
【００３１】
後側の切り欠き４０を挟む両端部には図６に示すように、略上方へ突出する位置決め突起４１が形成され、防振ゴム１３における外周部２６の下端部と嵌合位置決めするようになっている。
【００３２】
円弧状外周部３１の外周面には、図７に示すように外方へ解放された略コ字状断面の溝２３が形成され、その長手方向両端は切り欠き３９及び４０へ達する。後側の切り欠き４０はさらに溝２４へ連通することにより、主液室２０と副液室２１を連通するオリフィス通路２２が形成されている。
なお、図５及び６に示す前側の切り欠き３９は前側の外周部２６を嵌合する。この切り欠き３９に嵌合する外周部２６には溝２４が形成されていないのでオリフィス通路２２はここで止まっている。
【００３３】
次に、本実施例の作用を説明する。図３において、内筒１１へエンジン側から大荷重が入力し、内筒１１が下方へ過大変位すると、この内筒１１をストッパ１４が受け止める。このとき、上側ストッパ２８が受け止め面３２と接触するので、衝撃が緩和される。
【００３４】
また、図２に示すように、内筒１１へ左右方向の大きな荷重がかかり、側壁１８が仮想線で示すよう大きく変形するとコーナー部３５へ接触する。このとき、コーナー部３５には受け止め面３２から左右側面３３にかけて溝３６が形成されており、この溝３６によってストッパ本体部３０の上部が接触面積低減構造をなしているので、この部分が摩擦低減部となって、側壁１８との接触時における摩擦が低減されて異音の発生を低減できる。
【００３５】
しかもストッパ１４を略台形とし、そのコーナー部３５に摩擦低減部を設けたので、防振ゴム１３の側壁１８が最初に接触するコーナー部３５において接触時の摩擦を低減できる。また溝３６によりストッパ本体部３０に凹凸からなる接触面積低減構造を設けたので、摩擦低減部を容易に形成できる。そのうえコーナー部３５を跨ぐ溝３６により側壁１８との間に作動液体を逃がし易くなり、作動液体の流動を円滑化できる。
【００３６】
また、ストッパ本体部３０と側壁１８との接触により衝突を緩和でき、打音の発生をより小さくする。そのうえ、ストッパ１４を設けた円筒型ブッシュマウントにおいては、このストッパ１４の表面側に軽微な加工乃至は変更をするだけで済むから、液封式又は非液封式のの円筒型ブッシュマウント対して容易に適用できる。
【００３７】
さらに、受け止め面３２の前後端部に前後の側面３４側へかけて溝３６を形成すればアーム部２５との接触時における摩擦音を低減できる。このような接触は、前進側から後進側へのギヤチェンジ等において、アーム部２５の前後一方側が沈み込む様に過大変位するときに生じる可能性がある。
【００３８】
なお、本願発明は上記実施例に限定されず種々に変形や応用が可能であり、例えば、摩擦低減部は、適当な減摩剤で表面を形成することによっても可能である。また、接触面積低減構造を採用する場合でも、溝の形成のみならず、散点状又は突条等の凸部を設けることにより凹凸部として形成してもよい。
【００３９】
そのうえ、少なくともストッパ１４の受け止め面３２側を弾性部材で構成してもよい。このようにすれば接触時の異音発生を緩和できる。この場合には受け止め面３２を防振ゴム１３と同種又は別種のゴム又は弾性のあるエラストマー等で構成できる。但しストッパ本体部３０も弾性体として一体に形成してもよい。
【００４０】
しかも、受け止め面３２を弾性体としてここに溝３６を設けた場合には、内筒１１を受け止めるとき、まず溝３６周囲に部分が比較的容易に圧縮され、その次に受け止め面３２の全体が圧縮されるから、内筒１１側の変位量に応じて圧縮量が段階的に変化するので、ストッパ１４が非線形的なバネ定数を発揮して受け止めることができる。
【００４１】
さらに、防振装置としては、液封式及び非液封式を問わない。また円筒型ブッシュ型のみならず、円錐形マウント等公知の種々形式に適用できる。そのうえエンジンマウントのみならずサスペンション用等各種用途が可能であり、さらには自動車用以外の各種用途にも適用できる。また、ストッパの設け方は、逆の第１の取付部材側から第２の取付部材側へ突出させることもできる。
【図面の簡単な説明】
【図１】実施例に係るエンジンマウントの正面図
【図２】図１の２−２線断面図
【図３】図２の３−３線断面図
【図４】ストッパの正面図
【図５】ストッパの上面図
【図６】図５の６−６線断面図
【図７】図５の７−７線断面図
【図８】従来例の概略断面図
【符号の説明】
１０：エンジンマウント、１１：内筒、１２：外筒、１３：防振ゴム、１４：ストッパ、２０：主液室、２１：副液室、２２：オリフィス通路、３０：ストッパ本体部、３２：受け止め面、３３：左右側面、３５：コーナー部、３６：溝[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vibration isolator suitable for an engine mount or the like, and more particularly, to a device provided with a stopper and having reduced contact sound between the stopper and the vibration isolating rubber.
[0002]
[Prior art]
Various types of vibration isolator used for engine mounts and the like are known. For example, a cylindrical bush type engine mount has an anti-vibration rubber between the inner cylinder 1 and the outer cylinder 2 as schematically shown in FIG. 3, the stopper 4 is projected from the outer cylinder 2 side toward the inner cylinder 1 side, and when the inner cylinder 1 is excessively displaced downward, this is received by the stopper 4.
[0003]
[Patent Document 1]
JP-A-7-169642 [Patent Document 2]
Japanese Patent Laid-Open No. 2000-46097
[Problems to be solved by the invention]
In FIG. 8, when this engine mount is arranged so that the left-right direction of the figure is the front-rear direction of the vehicle, a large load is applied to the inner cylinder 1 at the time of large vibration, so that not only the vertical direction of the figure but also If it is greatly displaced in various directions substantially perpendicular to each other, a part of the anti-vibration rubber 3 may come into contact with the upper surface of the stopper 4 as indicated by a virtual line, and noise may be generated due to friction.
Therefore, it is desired to reduce the generation of abnormal noise due to such contact between the stopper 4 and the vibration isolating rubber 3, and the present invention aims to realize this requirement.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention of claim 1 is a vibration isolator in which a first attachment member attached to the vibration source side and a second attachment member attached to the vibration receiving side are connected by an anti-vibration rubber.
A liquid chamber is provided in the anti-vibration rubber, and a stopper that protrudes from one side of the first mounting member or the second mounting member to the other side is provided in the liquid chamber,
This stopper has a substantially trapezoidal shape including a receiving surface as a top and a side surface provided around the receiving surface, and a plurality of formed from the receiving surface to the side surface across the corner portion of the receiving surface and the side surface. a groove is provided, wherein the friction reducing unit is formed on the portion contacting vibration isolating rubber and including at least the corner portion of the surface of the stopper by the plurality of grooves, when the vibration isolating rubber is in contact with the corner portion, a corner The working liquid is allowed to escape by a groove straddling the part .
[0006]
According to a second aspect of the present invention, in the first aspect of the invention, the friction reducing portion has a contact area reducing structure by unevenness.
[0007]
According to a third aspect of the present invention, in the first or second aspect, the stopper has a substantially trapezoidal shape including a receiving surface and a side surface which are top portions, and the friction reducing portion is formed at a corner portion of the receiving surface and the side surface. It is characterized by that.
[0008]
According to a fourth aspect of the present invention, in the third aspect of the invention, the friction reducing portion includes a plurality of grooves formed across the corner portion.
[0009]
According to a fifth aspect of the present invention, in the first aspect, the first mounting member is an inner cylinder, and the second mounting member is an outer cylinder that surrounds the inner cylinder. And the stopper protrudes from the outer cylinder side to the inner cylinder side.
[0010]
【The invention's effect】
According to the first aspect of the present invention, since the friction reducing portion is provided in the stopper, when the anti-vibration rubber contacts the stopper, the friction is reduced and the generation of abnormal noise can be reduced.
[0011]
According to the second aspect of the present invention, since the contact area reducing structure made of unevenness is provided on the stopper, the friction reducing portion can be easily formed.
[0012]
According to the third aspect, since the stopper is substantially trapezoidal and the friction reducing portion is provided at the corner portion thereof, the friction at the time of contact at the corner portion where the anti-vibration rubber first comes into contact is reduced, and the abnormal noise is efficiently generated. Generation can be reduced.
[0013]
According to the fourth aspect, since the friction reducing portion according to the third aspect is configured by the groove straddling the corner portion, the friction reducing portion can be easily provided on the corner portion.
[0014]
According to the fifth aspect, the present invention can be easily applied to a cylindrical bush mount provided with a stopper.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment applied to an automotive cylindrical bush type engine mount will be described with reference to the drawings. 1 is a front view of the engine mount, FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1, FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 6 is a cross-sectional view taken along line 6-6 in FIG. 5, and FIG. 7 is a cross-sectional view taken along line 7-7 in FIG.
[0016]
First, in FIGS. 1 to 3, the engine mount 10 includes an inner cylinder 11, an outer cylinder 12 that surrounds the inner cylinder 11, and a vibration isolating rubber 13 that connects between them. The inner cylinder 11 is a pipe-like member made of an appropriate rigid material such as metal, and is attached to an engine (not shown) which is a vibration source by a connecting member (not shown) such as a bolt passed through the hollow portion. The inner cylinder 11 forms a first attachment member.
[0017]
The outer cylinder 12 is a cylindrical member made of a suitably rigid material such as metal, and includes the outer cylinder 12 in an eccentric position and is attached to a vehicle body on the vibration receiving side (not shown) by a bracket 15. The outer cylinder 12 forms a second attachment member.
[0018]
In this embodiment, in the state shown in FIG. 1, the vertical direction is the vertical direction of the vehicle body, and this direction is the main vibration input direction Z for the engine mount 10. The left-right direction is the front-rear direction X of the vehicle body, and the left side of the figure is the front side of the vehicle body and the right side is the rear side of the vehicle body. In addition, let the axial direction of the inner cylinder 11 be a Y direction. The Y direction is the left-right direction of the vehicle body, and it is assumed that the left side in FIG. 2 is the left side of the vehicle and the right side is the right side of the vehicle.
[0019]
The anti-vibration rubber 13 is made of a known rubber-like material such as natural or synthetic, and floats and supports the inner cylinder 11 with respect to the outer cylinder 12 to exhibit a predetermined spring elasticity. Above the inner cylinder 11, a curb 16 penetrating in the axial direction of the inner cylinder 11 is formed, and a diaphragm 17 is formed on the inner surface of the outer cylinder 12 facing the inner cylinder 11 across the curb 16.
[0020]
Below the curb 16, left and right side walls 18 are formed. As shown in FIG. 2, a main liquid chamber 20 is formed between the side walls 18, and an incompressible known working liquid is sealed therein. A stopper 14 having a substantially trapezoidal shape in the cross section in the Y-axis direction in FIG. 2 is provided in the main liquid chamber 20 so as to protrude from the outer cylinder 12 toward the inner cylinder 11, and when the inner cylinder 11 is excessively displaced downward, It is supposed to take it.
[0021]
The diaphragm 17 defines a sub liquid chamber 21 between the inner surface of the outer cylinder 12 above the tick 16 and expands and contracts into the tick 16 to compensate for the volume change of the sub liquid chamber 21. Although it is a flexible member formed integrally with the rubber 13, it has a spring elasticity that is negligibly small as a rubber spring that constitutes the engine mount 10.
[0022]
The secondary liquid chamber 21 communicates with the main liquid chamber 20 through the orifice passage 22, and the liquid moves between the main liquid chamber 20 and the secondary liquid chamber 21 due to the volume change of the main liquid chamber 20 caused by the vertical movement of the inner cylinder 11. By flowing, the liquid column resonates at a predetermined vibration frequency in the orifice passage 22. The orifice passage 22 is a known damped orifice passage having a resonance point in a low frequency region.
[0023]
As is apparent from FIG. 3, the orifice passage 22 is formed between the inner peripheral surface of the outer cylinder 12 by the groove 23 formed in the outer peripheral portion of the stopper 14 and the groove 24 formed in the outer peripheral portion of the vibration isolating rubber 13. Is done.
[0024]
The anti-vibration rubber 13 includes an arm portion 25 that extends from the inner cylinder 11 back and forth in a cross section orthogonal to the axis of the inner cylinder 11 shown in FIG. The upper surface of the arm portion 25 faces the curb 16 and the lower surface faces the main liquid chamber 20. The left and right ends of the arm portion 25 are continuous with the side wall 18, and the arm portion 25 and the side wall 18 form an elastic wall portion of the main liquid chamber 20.
[0025]
The arm portion 25 is a main portion as an anti-vibration rubber that receives a load mainly due to elastic deformation in the shear direction, and its radially outer peripheral end portion in FIG. 3 is continuous with the outer peripheral portion 26, and the outer peripheral portion 26 has a diaphragm. It continues to 17. The anti-vibration rubber 13 includes a diaphragm 17, a side wall 18, an arm portion 25, and an outer peripheral portion 26 that are integrally formed continuously. The groove 24 is formed in the outer peripheral portion of the outer peripheral portion 26.
[0026]
Further, a covering portion 27 is formed around the inner cylinder 11 from the radially inner peripheral end portion of the arm portion 25, and a lower portion thereof serves as an upper stopper 28 protruding into the main liquid chamber 20. .
[0027]
The stopper 14 is arranged in the main liquid chamber 20 so as to form an interval between the side wall 18 and the determination in the illustrated initial state. However, when there is a large load input from the engine side to the inner cylinder 11 and the inner cylinder 11 is displaced downward and sinks greatly, the stopper 14 contacts the upper stopper 28 and receives it. Also, when the side wall 18 is greatly deformed in the left-right direction as indicated by the phantom line in FIG. 2 due to a large displacement in the axial direction of the inner cylinder 11 or when the gear is changed from forward to reverse, one of the arm portions 25 is When sinking and deforming like the phantom line in FIG. 4, the side wall 18 and the arm portion 25 come into contact with the stopper 14.
[0028]
As shown in FIGS. 4 to 7, the stopper 14 is made of a material having appropriate rigidity such as 6-6 nylon, and is formed integrally with the stopper main body 30 protruding into the main liquid chamber and the outer cylinder 12. And an arcuate outer peripheral portion 31 along the inner surface. The upper surface of the stopper main body 30 is substantially flat perpendicular to the Z direction, forms a receiving surface 32 for receiving the inner cylinder 11, and further includes left and right side surfaces 33 parallel to the right in the Z direction. However, the front and rear side surfaces 34 are relatively gentle slopes of about 45 ° (FIG. 4).
[0029]
4 and 5, the groove 36 extends from the receiving surface 32 to the left and right side surfaces 33 across the left and right corner portions 35 (see FIG. 7) extending in the longitudinal direction between the receiving surface 32 and the left and right side surfaces 33. A groove 36 is formed. A plurality and a suitable number of the grooves 36 are formed in the longitudinal direction along the corner portion 35 at the same time when the stopper 14 is formed, or are formed by machining afterward, and the central portion of the upper surface is discontinuous. However, it is optional to make it continuous. Due to the groove 36, the receiving surface 32 of the stopper 14 is uneven to form a contact area reducing structure.
[0030]
The stopper main body 30 is formed with a through hole 38 extending in the left and right directions on the front and rear sides of the central column portion 37. Further, as apparent in FIG. 5, notches 39 and 40 are formed in the center in the width direction at both ends in the circumferential direction of the arc-shaped outer peripheral portion 31, and the rear notch 40 is more than the front notch 39. It is getting bigger.
[0031]
As shown in FIG. 6, positioning protrusions 41 projecting substantially upward are formed at both ends of the rear notch 40 so as to be fitted and positioned with the lower end portion of the outer peripheral portion 26 of the vibration-proof rubber 13. ing.
[0032]
As shown in FIG. 7, a groove 23 having a substantially U-shaped cross section released outward is formed on the outer peripheral surface of the arc-shaped outer peripheral portion 31, and both ends in the longitudinal direction reach notches 39 and 40. The rear cutout 40 further communicates with the groove 24 to form an orifice passage 22 that communicates the main liquid chamber 20 and the sub liquid chamber 21.
5 and 6, the front notch 39 fits the front outer peripheral portion 26. Since the groove 24 is not formed in the outer peripheral portion 26 fitted into the notch 39, the orifice passage 22 stops here.
[0033]
Next, the operation of this embodiment will be described. In FIG. 3, when a large load is input to the inner cylinder 11 from the engine side and the inner cylinder 11 is excessively displaced downward, the inner cylinder 11 is received by the stopper 14. At this time, the upper stopper 28 comes into contact with the receiving surface 32, so that the impact is alleviated.
[0034]
Further, as shown in FIG. 2, a large load in the left-right direction is applied to the inner cylinder 11, and when the side wall 18 is greatly deformed as indicated by an imaginary line, it contacts the corner portion 35. At this time, a groove 36 is formed in the corner portion 35 from the receiving surface 32 to the left and right side surfaces 33, and the upper portion of the stopper main body 30 has a structure for reducing the contact area by the groove 36. Thus, friction at the time of contact with the side wall 18 is reduced, and generation of abnormal noise can be reduced.
[0035]
Moreover, since the stopper 14 has a substantially trapezoidal shape and a friction reducing portion is provided at the corner portion 35, the friction at the time of contact can be reduced at the corner portion 35 where the side wall 18 of the vibration isolating rubber 13 first contacts. Further, since the stopper main body portion 30 is provided with a contact area reducing structure made of unevenness by the groove 36, the friction reducing portion can be easily formed. In addition, the groove 36 straddling the corner portion 35 makes it easy for the working liquid to escape between the side wall 18 and the flow of the working liquid can be smoothed.
[0036]
Further, the collision between the stopper main body 30 and the side wall 18 can be mitigated, and the occurrence of hitting sound is further reduced. In addition, in the cylindrical bush mount provided with the stopper 14, it is only necessary to make a slight process or change on the surface side of the stopper 14, so that the cylindrical bush mount of the liquid seal type or the non-liquid seal type is used. Easy to apply.
[0037]
Further, if the groove 36 is formed on the front and rear end portions of the receiving surface 32 toward the front and rear side surfaces 34, the frictional noise at the time of contact with the arm portion 25 can be reduced. Such a contact may occur when the front and rear sides of the arm portion 25 are excessively displaced so as to sink in a gear change or the like from the forward side to the reverse side.
[0038]
In addition, this invention is not limited to the said Example, A various deformation | transformation and application are possible, for example, a friction reduction part is also possible by forming the surface with a suitable lubricant. Even when the structure for reducing the contact area is adopted, not only the formation of the grooves but also the projections and depressions may be formed by providing projections such as dots or ridges.
[0039]
In addition, at least the receiving surface 32 side of the stopper 14 may be formed of an elastic member. In this way, the generation of abnormal noise during contact can be alleviated. In this case, the receiving surface 32 can be made of the same kind or different kind of rubber from the anti-vibration rubber 13 or an elastic elastomer. However, the stopper main body 30 may also be integrally formed as an elastic body.
[0040]
Moreover, when the receiving surface 32 is used as an elastic body and the groove 36 is provided here, when the inner cylinder 11 is received, the portion is first compressed relatively easily around the groove 36, and then the entire receiving surface 32 is fully compressed. Since it is compressed, the amount of compression changes stepwise according to the amount of displacement on the inner cylinder 11 side, so that the stopper 14 can receive and receive a non-linear spring constant.
[0041]
Further, the vibration isolator may be either a liquid seal type or a non-liquid seal type. Moreover, it can be applied not only to the cylindrical bush type but also to various known types such as a conical mount. In addition, it can be used not only for engine mounts but also for suspensions and the like, and can also be applied to various uses other than automobiles. Further, the stopper may be provided so as to protrude from the reverse first mounting member side to the second mounting member side.
[Brief description of the drawings]
1 is a front view of an engine mount according to an embodiment. FIG. 2 is a cross-sectional view taken along line 2-2 in FIG. 1. FIG. 3 is a cross-sectional view taken along line 3-3 in FIG. ] Top view of stopper [FIG. 6] Sectional view taken along line 6-6 in FIG. 5 [FIG. 7] Sectional view taken along line 7-7 in FIG.
10: Engine mount, 11: Inner cylinder, 12: Outer cylinder, 13: Anti-vibration rubber, 14: Stopper, 20: Main liquid chamber, 21: Sub liquid chamber, 22: Orifice passage, 30: Stopper body, 32: Receiving surface, 33: Left and right side surfaces, 35: Corner part, 36: Groove

Claims

In the vibration isolator in which the first attachment member attached to the vibration source side and the second attachment member attached to the vibration receiver side are connected by an anti-vibration rubber,
A liquid chamber in which a working liquid is sealed in the vibration isolating rubber is provided, and a stopper that protrudes from one side of the first mounting member or the second mounting member to the other side is provided in the liquid chamber,
This stopper has a substantially trapezoidal shape including a receiving surface which is a top portion and a side surface provided around the receiving surface, and a plurality of formed from the receiving surface to the side surface across the corner portion of the receiving surface and the side surface. A groove is provided, and a friction reducing portion is formed in a portion of the stopper surface that comes into contact with the anti-vibration rubber including at least the corner portion by the plurality of grooves, and when the anti-vibration rubber contacts the corner portion, the corner An anti-vibration device characterized in that the working liquid is allowed to escape by a groove straddling the part .

The first mounting member is an inner cylinder, and the second mounting member is an outer cylinder surrounding the inner cylinder, thereby forming a cylindrical bush as a whole, and the stopper from the outer cylinder side. 2. The vibration isolator according to claim 1, wherein the vibration isolator protrudes toward the inner cylinder.

The anti-vibration rubber includes a pair of side walls facing the axial direction of the inner cylinder, the stopper is disposed between the pair of side walls, and the side surface includes a surface facing the pair of side walls. The vibration isolator according to claim 2, wherein the groove is formed on a side surface of the vibration isolator.

The anti-vibration rubber includes an arm part that connects the inner cylinder and the outer cylinder and surrounds a part of the liquid chamber, and the side surface includes a surface that faces the arm part, and a surface that faces the arm part. The vibration isolator according to claim 2, wherein the groove is formed.