JP2004044772A

JP2004044772A - Liquid seal vibration-proof device

Info

Publication number: JP2004044772A
Application number: JP2002245506A
Authority: JP
Inventors: Toru Sakamoto; 坂本　徹
Original assignee: Yamashita Rubber Co Ltd
Current assignee: Yamashita Rubber Co Ltd
Priority date: 2002-05-16
Filing date: 2002-08-26
Publication date: 2004-02-12
Anticipated expiration: 2022-08-26
Also published as: JP4137556B2

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem wherein when a lateral membrane for adjusting internal pressure is provided at side part of a main liquid chamber and deformation is restricted by a lateral membrane stopper, since high spring is hardly obtained in cases where the stopper is made of rubber, it becomes difficult that resonance efficiency is made high and when it is controlled by suction negative pressure of an engine, expensive material excellent in gasoline-resistance must be used, and to realize enhancement of resonance efficiency and reduction of cost by the stopper. <P>SOLUTION: An internal pressure control means provided on side part of the main chamber is constituted by the membrane 10 formed on side surface of elastic cylindrical member 8 constituted separately from elastic body 5 and inserted/fixed into the chamber 20 and the stopper 11 mounted to side surface wall of the chamber 20. In the stopper 11, stopper body and pipe 13 are integrally formed by resin and a mounting insert member 43 is insert-molded. A membrane operation chamber 15 formed between the membrane 10 and the stopper 11 is made to negative pressure by suction negative pressure. When the membrane 10 is adsorbed/restricted on the stopper 11, the stopper is not deformed because it is made of resin and it becomes high spring to enhance resonance efficiency so as to dispense with expensive material superior in antigasoline quality. <P>COPYRIGHT: (C)2004,JPO

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の液封防振装置に係り、特に主液室の内圧をコントロールする可動膜を設けたものに関する。
【０００２】
【従来の技術】
特開２００２−７０９３１号には、主液室に臨む側部に弾性本体部と連続する可動膜を設け、かつ外部から略漏斗状のホルダを取付けて作動室を形成し、負圧又は大気開放に選択切り換えすることにより、可動膜をフリーにしたり拘束して変形を規制することが開示されている。また、ホルダ内には、ホルダと別体に形成されたゴム製の可動膜ストッパを設け、これにより可動膜の変形を規制している。
【０００３】
【発明が解決しようとする課題】
ところで、上記従来の可動膜ストッパは、ゴムで構成しており、可動膜が当接したときも、弾性変形を許容するようになっていた。しかし、このようにすると、大振動入力に対して、可動膜の弾性変形を防止してより高バネを得たい場合でも、これを実現できないことになる。そこで、大振動入力に対しては、可動膜ストッパが弾性変形せず、しかも可動膜のバネ特性を非線形的にできることが望まれる。
【０００４】
また、可動膜ストッパがゴムであると、可動膜ストッパと可動膜がゴム同士で接触するため、摩耗変形を招くおそれもあり、このような変形を生じにくくすることも望まれていた。そのうえ熱やガソリンによる劣化の可能性があり、長期使用により形状は変化してバネ特性の変化を招くおそれがあるため、耐久性の向上が望まれた。また、可動膜ストッパをホルダと別に形成した場合は構成部品点数が多くなって組立が複雑になるので、可動膜ストッパの構造簡素化も望まれる。さらに、耐ガソリン性等に優れた材料を要求される可動膜が弾性本体部と一体にすると、弾性本体部全体を高価な特殊材料で構成しなければならないことになるので、可動膜と弾性本体部を別体にすることも望まれている。
本願は、これらの要請の実現を目的とする。
【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の液封防振装置は、振動発生側又は振動受け側のいずれか一方側へ取付けられる第１取付部材と、他方側へ取付けられる第２取付部材と、これらの間に介在される弾性本体部材とを備え、弾性本体部材を壁の一部とする主液室と、この主液室と仕切り部材で仕切られ、可撓膜部材で覆われる副液室と、これら両液室を連通するオリフィス通路とを備えた液封防振装置において、
前記主液室に臨んでその内圧変動を吸収するための可動膜と、この可動膜の変形規制を行う可動膜ストッパと、この可動膜ストッパに対して前記可動膜の弾性変形を自由にするフリー状態と、前記可動膜ストッパに対して前記可動膜を密着させた拘束状態とに変化させる内圧制御手段とを備えるとともに、
前記可動膜ストッパを耐熱性及び耐ガソリン性樹脂材料で構成したことを特徴とする。
【０００６】
請求項２は、上記請求項１において、前記可動膜が前記弾性本体部と別体に形成され、前記主液室内へ挿入固定される弾性筒部材の一部に形成されることを特徴とする。
【０００７】
請求項３は、上記請求項２において、前記可動膜及び前記可動膜ストッパがそれぞれ非円形をなすことを特徴とする。
【０００８】
【発明の効果】
請求項１によれば、可動膜ストッパを樹脂で構成したので、可動膜ストッパを複数の構成部を有しない単一部材として成形できるので構造を簡素化できる。また可動膜が当接した状態で変形することがなく、可動膜の弾性変形を確実に規制できるから、フリー状態と規制状態の間で可動膜のバネ特性を顕著な非線形にできる。しかも可動膜との接触もゴムとゴム相互の接触ではなくなるから、摩耗が少なくなって耐久性が向上し、形状変化が少なくバネ特性が安定する。そのうえ耐熱性及び耐ガソリン性に優れるため耐久性が向上する。
【０００９】
請求項２、可動膜を弾性本体部と別体に形成され、主液室内へ挿入固定される弾性筒部材の一部に形成したので、可動膜の形成並びに主液室に対する取付けが容易になり、しかも弾性筒部材のみを耐熱性及び耐ガソリン性の高い特殊材料とすれば足り、弾性本体部を従来同様の材料のままとすることができる。
【００１０】
このとき、請求項３のように可動膜を非円形にしても、弾性筒部材を構成するインサート部材の一部に非円形の開口を予め形成しておけば、弾性部材のインサート成形により簡単に形成できる。また可動膜ストッパも、可動膜に対応する非円形形状を樹脂成形により容易に形成できる。
【００１１】
【発明の実施の形態】
以下、図面に基づいて、エンジンマウントとして構成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全断面図（図２の１−１線断面図）、図２は平面図（図１のＺ矢示図）図３は側面図（図１のＸ矢示図）、図４はストッパ取付部の概略斜視図、図５はストッパ部の拡大断面図、図６はストッパブラケットの変形例を示す図である。
【００１２】
まず、図１において、符号１は突部１ａでエンジン側へ取付けられる第１取付部材、２はボルト等により車体側へ取付けられる第２取付部材、５は弾性本体部材であり、ゴム等の適宜弾性部材からなり、略円錐状のドーム部６とこれに連続してドーム部６の開口縁部をなす脚部７を有する。脚部７は弾性筒部材８の上部に密接している。
【００１３】
第２取付部材２の上半部側はフランジ部材３と筒状部材４を内外に嵌合一体化してあり、筒状部材４の内側には弾性筒部材８が嵌合されている。弾性筒部材８の一部で、第２取付部材２のフランジ部材３と筒状部材４が重なり合う部分に形成された取付穴９ａ，９ｂと対応する位置に横膜１０が形成されている。横膜１０は本願発明における可動膜に相当する。
【００１４】
取付穴９ａ，９ｂ内には横膜ストッパ１１が嵌合されている。横膜ストッパ１１は取付穴９ａ，９ｂへ嵌合するストッパ本体部１２とパイプ部１３をポリプロピレン等の耐熱性及び耐ガソリン性に優れた樹脂により一体に形成したものである。パイプ部１３は切換バルブ１４ａへ接続される。
【００１５】
切換バルブ１４ａは、大気開放とエンジンの吸気負圧等の負圧源に対する接続とを切り換えることにより、横膜１０をストッパ本体部１２上へ密着固定する拘束状態と、横膜１０をフリーにして自由に弾性変形可能な状態とのいずれかに選択切り換えする。横膜１０及び横膜ストッパ１１はそれぞれ耐熱性及び耐ガソリン性に優れた材料が用いられている。
【００１６】
弾性筒部材８の下端側開口部は仕切り部材１６で覆われる。この仕切り部材１６は、上部仕切り１７、中間仕切り１８及び下部仕切り１９の３部材を重ね合わせた構造であり、各部材はそれぞれ合成樹脂等の適宜剛性材料から形成される。仕切り部材１６には後述する第１及び第２オリフィス通路が設けられる。
【００１７】
仕切り部材１６と弾性本体部材５との間に、弾性本体部材５を壁の一部とする主液室２０が形成される。仕切り部材１６の主液室２０と反対側にはダイアフラム２１で覆われた副液室２２が形成され、これら主液室２０及び副液室２２内には非圧縮性の液体が封入される。
【００１８】
上部仕切り１７と中間仕切り１８の間及び中間仕切り１８と下部仕切り１９の間には螺旋状をなす第１オリフィス通路である減衰オリフィス通路２３が形成され、その一端は上部仕切り１７と中間仕切り１８の間に形成されて主液室へ開口する共通通路２４へ通じ、他端は下部仕切り１９の一部に形成された開口部１９ａで副液室２２へ通じている。
【００１９】
減衰オリフィス通路２３は常時主液室２０と副液室２２を連通して、一般走行時における振動等の比較的低周波数でかつ振幅の大きな振動に対して減衰力を発生してこれを吸収するようになっている。
【００２０】
共通通路２４は第２オリフィス通路であるアイドルオリフィス通路２５へも同時に連通する。アイドルオリフィス通路２５は、上部仕切り１７の中央に形成された中央ホール２６、及びこれに対応して中間仕切り１８の中央に形成された開口２７及び下部仕切り１９の中央に形成された開口である出口２８を介して副液室２２へ通じている。出口２８はダイアフラム２１の中央部に形成された厚肉部２１ａで開閉される。
【００２１】
厚肉部２１ａは、下部仕切り１９における出口２８の周囲部分であるシート部へ接離することにより、アイドルオリフィス通路２５の副液室２２側開口をなす出口２８を開閉する。この出口２８が開いたときは主液室２０と副液室２２を連通し、アイドル時の振動を減衰オリフィス通路２３よりも高周波側で液柱共振して吸収する。
【００２２】
厚肉部２１ａの開閉動作は別体の開閉部材３０で行われる。開閉部材３０は厚肉部２１ａを押し上げるための中央突部３１を有する弾性体からなる上部３２と樹脂製の底部３３を合わせ、間に中空の開閉部作動室３４を形成するように密閉し、開閉部作動室３４内に配置したリターンスプリング３５により、中央突部３１を厚肉部２１ａへ押し当てて、厚肉部２１ａが出口２８の周囲へ密着するように押し上げ側へ付勢する。
【００２３】
底部材３３の中央部に形成されたパイプ部３６は切換バルブ１４ｂへ接続し、大気開放状態と負圧状態を切り換える。このとき開閉部材３０と前記横膜１０をそれぞれ同期して切り換える場合には切換バルブ１４ａ及び１４ｂを共通化することもできる。
【００２４】
開閉部作動室３４内を負圧状態にすると開閉部材３０の中央突部３１をリターンスプリング３５に抗して図の下方へ引き下げ、その結果、厚肉部２１ａを出口２８の周囲から離して出口２８を開放し、アイドルオリフィス通路２５を主液室２０及び副液室２２と連通させる。逆に大気開放すれば、中央突部３１がリターンスプリング３５により押し上げられ、厚肉部２１ａが出口２８を閉じる。
【００２５】
開閉部材３０は、上部３２と底部材３３の各外周部を重ね合わせ、全周をリング部材３７でカシメることにより一体化され、このリング部材３７を下部円筒部材３８の下部内側へ固定される。下部円筒部材３８は第２取付部材２の下半部側をなす金属製部材であり、その上端部を筒状部材４の下端部とカシメることにより一体化される。このときこのカシメ部４ｂに弾性筒部材８の下端部とダイアフラム２１の外周部に一体化されているインサートリング２１ｂの上部フランジ２１ｃとがそれぞれ挟持されて同時に固定される。
【００２６】
また、筒状部材４と下部円筒部材３８とのカシメ時に、弾性筒部材８と仕切り部材１６も同時に固定される。すなわち、弾性筒部材８は上端部へ脚部７が圧接し、下端部が仕切り部材１６の上部仕切り１７の外周部上面へ当接し、さらに仕切り部材１６のうち下部仕切り１９の外周部下端がインサートリング２１ｂの下部フランジ２１ｄに支持されるため、結局、脚部７と下部フランジ２１ｄとの間に挟持されて固定されることになる。
【００２７】
図２及び４に示すように、フランジ部材３の上部に外方へ折り曲げられて形成されたフランジ３ｂの一部を径方向へ突出させて張り出し部４０が設けられている。張り出し部４０は図２に明らかなように、図示状態の平面視で、中心Ｏとパイプ部１３を結ぶ線Ｌを挟んで左右へ略６０°程度づつ開いた位置に２ヶ所設けられ、張り出し部４０、４０にはリベット４１、４１により横膜ストッパ１１を直接固定している。
【００２８】
張り出し部４０は、フランジ部材３における本来のフランジ３ｂの外周部より張り出して形成され、かつ下部円筒部材３８のフランジ３８ａの内側に位置している。すなわち装置の大型化を回避するようにフランジ３８ａよりも引き込んだ位置に形成される。左右の張り出し部４０，４０の外側を結ぶ線Ｍはほぼ直線状であって、線Ｌ上におけるフランジ３ｂの最大張り出し部である先端部と同程度の位置を通っている。また張り出し部４０、４０やリベット４１、４１の間隔は任意であり、横膜ストッパ１１の大きさに応じて設定される。
【００２９】
図３及び図４に示すように、横膜ストッパ１１は、フランジ部材３の胴部３ａの周囲へ沿うようにフランジ３ｂの下方に配置され、リベット４１，４１により図の上下方向すなわち主たる振動の入力方向Ｚと平行な方向にて固定される。なお図４のフランジ部材３は弾性本体部材５（図１）を一体化する前の状態、筒状部材４は下部円筒部材３８（図１）との結合前の状態でそれぞれ示してある。
【００３０】
図４に明らかなように、横膜ストッパ１１は略円弧状をなして胴部３ａの周方向へ長く形成され（以下、この形状を横長という）、張り出し部４０，４０に設けられた取付穴４２，４２と、横膜ストッパ１１のインサート部材４３に形成されたフランジ４４に設けられている取付穴４５，４５を一致させてリベットで固定するようになっている。なお、胴部３ａ及び４ａに形成された取付穴９ａ，９ｂも横膜ストッパ１１に対応して横長に形成されている。
【００３１】
図５に示すように、インサート部材４３は略Ｌ字状断面をなす金属製部材であり、胴部３ａの外側に沿う本体部４６とその上部に略９０°外側へ屈曲して、張り出し部４０に沿うフランジ４４とを連続一体に形成したものである。なお、インサート部材４３はある程度の剛性及び耐久強度を有するものであれば、金属材料に限らず適当な樹脂材料であってもよい。
【００３２】
本体部４６の下半部はストッパ本体部１２中へインサートされ、横膜ストッパ１１を射出成形等によって成形するときに一体化されている。このインサート部材４３の下部側に穴４７が形成され、この穴４７によりストッパ本体部１２との結合を強固にするとともに、この穴４７の中央を貫通して通気穴４８が形成されている。通気穴４８はパイプ部１３の軸心部を通り、かつストッパ本体部１２の中央部を貫通して横膜作動室１５へ連通している。
【００３３】
ストッパ本体部１２は上端側が取付穴９ａ，９ｂに嵌合し、下端側は、胴部３ａの下端よりも下方へ延出しているため取付穴９ｂのみに嵌合する。
ストッパ本体部１２の横膜作動室１５に臨む面には最外周側突部５１、そのすぐ内側に多数の突起５２が一体に形成されている。突起５２は全体としてシート面５３をリング状に囲むように多数を点状に配設したものである。但し突起５２に代えて連続するリング状の突条に形成してもよい。シート面５３には通気穴４８の一端が開口している。
【００３４】
最外周側突部５１は、横膜１０の周囲部分へ常時圧接されるシール部をなす。但し、逆に横膜１０側からシール突起を突出させることもできる。突起５２はシート面５３の外周を規定し、横膜１０が弾性変形時にまず突起５２へ当接し、その次にシート面５３へ当接するよう、段階的な弾性変形を行わせることにより、横膜１０のバネをフリー状態、突起５２との接触時及びシート面５３との接触時の３段階に変化させ、非線形のバネ特性を生じさせるようになっている。
【００３５】
弾性筒部材８には芯金具として略筒状のインサート部材５４が一体成形されている。インサート部材５４の取付穴９ａ，９ｂと対応する位置は、これらと同形状をなす横穴５５が形成され、この横穴５５を覆う弾性筒部材８の一部が横膜１０となっている。横穴５５の縁部は最外周側突部５１に近接した位置となる。
【００３６】
弾性筒部材８は、耐熱性及び耐ガソリン性に優れた弾性材料、例えば、ヒドリンゴム、シリコンゴム、フッ素ゴム等からなり、インサート部材５４と一体形成することにより、横膜ストッパ１１の横長形状と対応した非円形をなす横膜１０を容易に形成できる。
【００３７】
インサート部材５４の上部は内向きのフランジ５６をなし、下部は外向きのフランジ５７をなす。フランジ５６の周囲にも弾性筒部材８の弾性部材が一体に形成されて弾性受部８ａをなし、ここに弾性本体部５の脚部７が圧接されて密着することにより脚部７と弾性受部８ａとの接合部をシールしている。なお、両部材からシール突起８ｂ及び７ａを設ける。
【００３８】
弾性筒部材８の下端部８ｃは筒状部材４の本体部４ａにおける取付穴９ｂ近傍部へ密接して筒状部材４と弾性筒部材８の間をシールするとともに、上部仕切り１７の外周部上面に密接する。このとき、一体に形成されたシール突起８ｄがシールを確実にする。また、ストッパ本体部は下部との当接部にも下端部８ｃにはシール突起８ｅを設ける。
【００３９】
フランジ５７の外周部は、下部円筒部材３８の上端フランジ及びインサートリング２１ｂの上部フランジ２１ｃに重なって、筒状部材４のフランジ部に設けたカシメ部４ｂによりカシメられて一体化する。
【００４０】
次に、本実施例の作用を説明する。まず、パイプ部１３の通気穴４８を大気開放して横膜１０の弾性変形をフリーにすれば、横膜１０は第１取付部材１からの微少振動入力により主液室２０の内圧変動に応じて自在に弾性変形し、主液室２０の内圧変化を吸収する。したがって、全体が低動バネとなる。
【００４１】
より大きな振動入力があると、横膜１０がシート面５３へ当接してその弾性変形が規制されるようになるため、横膜１０のバネが高くなり、このような大振動による横膜１０の過大な変形を防止して破損を防ぎ、横膜１０の耐久性を向上させることができる。
【００４２】
したがって、小さな振動入力には低バネとなり、より大きな振動入力に対してはそれ相応の非線形的に上昇した高バネとなるから、バネ定数を非線形的かつ広範囲に変化させて主液室２０における内圧上昇を吸収し、より理想的な振動吸収が可能になる。
【００４３】
また、切り換えバルブ１４ａによりパイプ部１３の通気穴４８を負圧源へ接続させれば、横膜作動室１５が負圧となるため、横膜１０はシート面５３へ密着され、弾性変形が規制される。この状態で、減衰オリフィス通路２３又はアイドルオリフィス通路２５の共振周波数近傍の振動入力があると、横膜１０の弾性変形が規制されているため、各オリフィス通路に対する液体流動量を多くでき、その結果、これらのオリフィス通路における液柱共振効率を大きくできる。なお、横膜１０の拘束は、減衰オリフィス通路２３又はアイドルオリフィス通路２５のいずれか一方に対してのみ行うこともできる。
【００４４】
このとき、突起５２を設けることにより、横膜１０とシート面５３の間に間隙を確保し、隣り合う突起５２間に形成される凹部を介して、横膜１０と最外周側突部５１近傍部との間に形成される間隙と横膜作動室１５の通気穴４８が開口する中央部とを連通させておくことができるから、横膜作動室１５の隅部における空気だまりの発生を防ぎ、エンジンルームの高温化による横膜作動室１５の容量変化を防止して横膜１０の膜剛性が変化をすることを防止できる。但し、空気だまりの発生による影響が少ない場合は、突起５２を点状ではなく、通気穴４８の開口部周囲を連続して囲むループ状の突条としてもよい。
【００４５】
本実施例における横膜１０は、主液室２０内へ挿入・固定される弾性筒部材８の一部を利用するので、非円形など複雑形状であっても成形容易である。しかも取付性及びシール性のいずれも優れたものとなる。また、弾性筒部材８を弾性本体部５と別体に構成したので、弾性筒部材８のみを耐熱性及び耐ガソリン性に優れたものにでき、弾性本体部５を高価な材料でなく通常のものとすることができるため、全体としてのコストを低減でき、耐久性を向上させることができる。
【００４６】
しかも、弾性本体部５と弾性筒部材８をシール７ａと８ｂにより、上部仕切り１７と弾性筒部材８をシール突起８ｄによりそれぞれ密着させることにより、これらの接合部におけるシール性を確保することができる。また、横膜１０に横膜ストッパ１２の一部を密着させたので、横膜１０の弾性を利用して横膜ストッパ１２との間を密にシールでき、その結果、横膜作動室１５を確実にシールできる。
【００４７】
また、横膜ストッパ１１は、インサート部材４３のフランジ４４を、フランジ部材３のフランジ３ｂに形成された張り出し部４０に対応してリベット４１，４１によって直接取付けるだけで固定できるので、特別な取付座を溶接で設ける必要がなく、取付が容易となり、溶接しない分だけ組立精度も高くなる。しかも、インサート部材４３は略Ｌ字形をなすとともに半円弧状をなすから、剛性が高くなり、変形に対する程度も大きくなり、リベット４１，４１にて２ヶ所のみでの固定が可能になる。
【００４８】
なお、インサート部材４３は、図６に示すように、断面が略９０°屈曲した状態よりもさらにθだけ傾けて鈍角にし、取付時に略９０°まで変形させて取付ければ、さらに密着が良好になる。逆に、筒状部材４の本体部４ａを下方が外方へ張り出すように傾斜されれば同様の効果が得られる。いずれにしてもリベット４１，４１の２ヶ所のみによる固定だけで足りることになる。
【００４９】
さらに、横膜ストッパ１１はインサート部材４３をインサートした状態でストッパ本体部１２とパイプ部１３を一体成形するので、従来のように組立時に複数部材を組み合わせる必要がなくなり、部品点数を削減でき、構造及び製造が簡単になる。
【００５０】
そのうえ、横膜ストッパ１１を耐熱性及び耐ガソリン性に優れた樹脂で構成したので、横膜１０が当接した状態で変形することがなく、横膜１０の弾性変形を確実に規制できるから、フリー状態と規制状態の間で可動膜のバネ特性を顕著な非線形にできる。しかも横膜１０との接触もゴムとゴム相互の接触ではなくなるから、摩耗が少なくなって耐久性が向上し、形状変化が少なくバネ特性が安定する。そのうえ耐熱性及び耐ガソリン性に優れるため耐久性が向上する。
【００５１】
なお、本願発明は上記の実施例に限定されず種々に変形等が可能であり、例えば、用途としてエンジンマウント以外の種々な防振装置に適用できる。
【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全断面図（図２の１−１線断面図）
【図２】図１のＺ矢示方向図
【図３】図１のＸ矢示方向図
【図４】横膜ストッパの取付を示す斜視図
【図５】横膜ストッパの取付部拡大断面図
【図６】インサート部材の別実施例を示す図
【符号の説明】
１：第１取付部材、２：第２取付部材、５：弾性本体部材、８：弾性筒部材、９ａ．９ｂ：取付穴、１０：横膜、１１：横膜ストッパ、１２：ストッパ本体部、１３：パイプ部、１５：横膜作動室、１６：仕切り部材、２０：主液室、２１：ダイアフラム、２２：副液室、２３：減衰オリフィス通路、２４：共通通路、２５：アイドルオリフィス通路、４０：張り出し部、４１：リベット、４３：インサート部材、４４：フランジ[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a liquid-sealing vibration isolator such as an engine mount, and more particularly to a device provided with a movable film for controlling the internal pressure of a main liquid chamber.
[0002]
[Prior art]
Japanese Patent Application Laid-Open No. 2002-70931 discloses that an operating chamber is formed by providing a movable membrane continuous with an elastic main body on a side facing a main liquid chamber, and attaching a substantially funnel-shaped holder from the outside to form a negative pressure or opening to the atmosphere. It is disclosed that the movable film is made free or restricted to restrict the deformation by selectively switching the movable film. In addition, a rubber movable film stopper formed separately from the holder is provided in the holder, thereby restricting deformation of the movable film.
[0003]
[Problems to be solved by the invention]
By the way, the above-mentioned conventional movable film stopper is made of rubber, and allows elastic deformation even when the movable film comes into contact. However, in this case, even if it is desired to obtain a higher spring by preventing elastic deformation of the movable film with respect to a large vibration input, this cannot be realized. Therefore, it is desired that the movable film stopper is not elastically deformed and that the spring characteristic of the movable film can be made nonlinear in response to a large vibration input.
[0004]
Further, if the movable film stopper is made of rubber, the movable film stopper and the movable film come into contact with each other with rubber, which may cause abrasion deformation, and it has been desired to make such deformation less likely to occur. In addition, there is a possibility of deterioration due to heat or gasoline, and the shape may change due to long-term use, resulting in a change in spring characteristics. Therefore, improvement in durability has been desired. In addition, if the movable film stopper is formed separately from the holder, the number of constituent parts increases and the assembly becomes complicated. Therefore, it is desired to simplify the structure of the movable film stopper. Furthermore, if the movable membrane that requires a material with excellent gasoline resistance and the like is integrated with the elastic body, the entire elastic body must be made of an expensive special material. It is also desired to have separate parts.
The present application aims to fulfill these requirements.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, a liquid seal vibration isolator according to claim 1 includes a first mounting member mounted on one of a vibration generating side and a vibration receiving side, a second mounting member mounted on the other side, A main liquid chamber having an elastic body member interposed between the main liquid chamber and the elastic body member as a part of a wall; and a sub liquid chamber partitioned by the main liquid chamber and a partition member and covered with a flexible membrane member. A liquid seal vibration isolator provided with an orifice passage communicating these two liquid chambers,
A movable film that faces the main liquid chamber and absorbs fluctuations in its internal pressure; a movable film stopper that regulates deformation of the movable film; and a free film that allows the movable film to freely elastically deform with respect to the movable film stopper. State, and an internal pressure control means for changing to a restricted state in which the movable film is brought into close contact with the movable film stopper,
The movable film stopper is made of a heat-resistant and gasoline-resistant resin material.
[0006]
According to a second aspect of the present invention, in the first aspect, the movable film is formed separately from the elastic main body, and is formed on a part of an elastic cylindrical member inserted and fixed into the main liquid chamber. .
[0007]
According to a third aspect, in the second aspect, the movable film and the movable film stopper each have a non-circular shape.
[0008]
【The invention's effect】
According to the first aspect, since the movable film stopper is made of a resin, the movable film stopper can be formed as a single member having no plural components, so that the structure can be simplified. In addition, since the elastic deformation of the movable film can be surely restricted without being deformed in the state where the movable film is in contact with the movable film, the spring characteristic of the movable film can be made significantly non-linear between the free state and the restricted state. In addition, since the contact with the movable film is no longer the contact between the rubber and the rubber, the wear is reduced, the durability is improved, the shape change is small, and the spring characteristics are stabilized. In addition, durability is improved due to excellent heat resistance and gasoline resistance.
[0009]
According to a second aspect of the present invention, since the movable film is formed separately from the elastic main body and formed as a part of the elastic cylindrical member inserted and fixed into the main liquid chamber, the formation of the movable film and the attachment to the main liquid chamber are facilitated. Moreover, it is sufficient if only the elastic cylinder member is made of a special material having high heat resistance and gasoline resistance, and the elastic main body can be made of the same material as the conventional one.
[0010]
At this time, even if the movable film is made non-circular as in claim 3, if a non-circular opening is formed in advance in a part of the insert member constituting the elastic cylindrical member, it can be easily formed by insert molding of the elastic member. Can be formed. The movable film stopper can also easily form a non-circular shape corresponding to the movable film by resin molding.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment configured as an engine mount will be described with reference to the drawings. FIG. 1 is a full sectional view of the engine mount (a sectional view taken along line 1-1 of FIG. 2), FIG. 2 is a plan view (shown by an arrow Z in FIG. 1), and FIG. 4 is a schematic perspective view of a stopper mounting portion, FIG. 5 is an enlarged sectional view of the stopper portion, and FIG. 6 is a diagram showing a modification of the stopper bracket.
[0012]
First, in FIG. 1, reference numeral 1 denotes a first mounting member mounted on the engine side by a protrusion 1a, 2 denotes a second mounting member mounted on the vehicle body side by a bolt or the like, 5 denotes an elastic body member, It has a substantially conical dome portion 6 made of an elastic member, and a leg portion 7 that forms an opening edge of the dome portion 6 continuously therewith. The leg 7 is in close contact with the upper part of the elastic tubular member 8.
[0013]
A flange member 3 and a cylindrical member 4 are fitted and integrated into and out of the upper half of the second mounting member 2, and an elastic cylindrical member 8 is fitted inside the cylindrical member 4. The horizontal membrane 10 is formed at a position corresponding to the mounting holes 9a and 9b formed in a part of the elastic cylindrical member 8 where the flange member 3 and the cylindrical member 4 of the second mounting member 2 overlap. The transverse film 10 corresponds to the movable film in the present invention.
[0014]
A transverse membrane stopper 11 is fitted in the mounting holes 9a and 9b. The transverse membrane stopper 11 is formed by integrally forming a stopper main body portion 12 and a pipe portion 13 fitted into the mounting holes 9a and 9b with a resin having excellent heat resistance and gasoline resistance such as polypropylene. The pipe section 13 is connected to the switching valve 14a.
[0015]
The switching valve 14a switches between opening to the atmosphere and connection to a negative pressure source such as an intake negative pressure of the engine, so that the diaphragm 10 is tightly fixed on the stopper body 12 and the diaphragm 10 is free. Selectively switch to any of the states that can be freely elastically deformed. The transverse film 10 and the transverse film stopper 11 are made of a material having excellent heat resistance and gasoline resistance, respectively.
[0016]
The lower end side opening of the elastic tubular member 8 is covered with the partition member 16. The partition member 16 has a structure in which three members, an upper partition 17, an intermediate partition 18, and a lower partition 19, are overlapped, and each member is formed of an appropriate rigid material such as a synthetic resin. The partition member 16 is provided with first and second orifice passages described later.
[0017]
A main liquid chamber 20 is formed between the partition member 16 and the elastic main body member 5 with the elastic main body member 5 as a part of a wall. On the opposite side of the partition member 16 from the main liquid chamber 20, a sub liquid chamber 22 covered with a diaphragm 21 is formed, and an incompressible liquid is sealed in the main liquid chamber 20 and the sub liquid chamber 22.
[0018]
Between the upper partition 17 and the intermediate partition 18 and between the intermediate partition 18 and the lower partition 19, there is formed a spiral orifice orifice passage 23 which is a first orifice passage. The other end communicates with a common passage 24 which is formed therebetween and opens to the main liquid chamber, and the other end communicates with the sub liquid chamber 22 through an opening 19 a formed in a part of the lower partition 19.
[0019]
The damping orifice passage 23 always communicates the main liquid chamber 20 and the sub liquid chamber 22, and generates and absorbs a damping force against relatively low frequency and large amplitude vibrations such as vibrations during normal driving. It has become.
[0020]
The common passage 24 simultaneously communicates with an idle orifice passage 25 which is a second orifice passage. The idle orifice passage 25 has a central hole 26 formed in the center of the upper partition 17, and an opening 27 correspondingly formed in the center of the intermediate partition 18 and an outlet formed in the center of the lower partition 19. It communicates with the auxiliary liquid chamber 22 through 28. The outlet 28 is opened and closed by a thick portion 21 a formed at the center of the diaphragm 21.
[0021]
The thick portion 21a opens and closes the outlet 28 that forms an opening on the side of the sub liquid chamber 22 of the idle orifice passage 25 by coming into contact with and separating from a sheet portion that is a peripheral portion of the outlet 28 in the lower partition 19. When the outlet 28 is opened, the main liquid chamber 20 and the sub liquid chamber 22 communicate with each other, and the vibration during idling is absorbed by the liquid column resonance on the high frequency side of the damping orifice passage 23.
[0022]
The opening / closing operation of the thick portion 21a is performed by a separate opening / closing member 30. The opening / closing member 30 is fitted with an upper part 32 made of an elastic body having a central projection 31 for pushing up the thick part 21a and a resin bottom part 33, and sealed so as to form a hollow opening / closing part working chamber 34 therebetween. The central projection 31 is pressed against the thick portion 21 a by a return spring 35 disposed in the opening / closing section working chamber 34, and the thick portion 21 a is urged upward so as to be in close contact with the periphery of the outlet 28.
[0023]
A pipe portion 36 formed at the center of the bottom member 33 is connected to the switching valve 14b, and switches between the open-to-atmosphere state and the negative pressure state. At this time, when switching the opening / closing member 30 and the transverse membrane 10 in synchronization with each other, the switching valves 14a and 14b can be shared.
[0024]
When the inside of the opening / closing section working chamber 34 is brought into a negative pressure state, the central projection 31 of the opening / closing member 30 is pulled downward in the drawing against the return spring 35, and as a result, the thick portion 21a is separated from the periphery of the outlet 28 and 28 is opened to allow the idle orifice passage 25 to communicate with the main liquid chamber 20 and the sub liquid chamber 22. Conversely, when the air is released to the atmosphere, the central projection 31 is pushed up by the return spring 35, and the thick portion 21a closes the outlet 28.
[0025]
The opening / closing member 30 is integrated by overlapping the outer peripheral portions of the upper portion 32 and the bottom member 33 and caulking the entire periphery with a ring member 37, and the ring member 37 is fixed to the lower inside of the lower cylindrical member 38. . The lower cylindrical member 38 is a metal member that forms the lower half of the second mounting member 2, and is integrated by caulking its upper end with the lower end of the tubular member 4. At this time, the lower end portion of the elastic tubular member 8 and the upper flange 21c of the insert ring 21b integrated with the outer peripheral portion of the diaphragm 21 are clamped and fixed to the caulking portion 4b at the same time.
[0026]
Further, at the time of caulking between the tubular member 4 and the lower cylindrical member 38, the elastic tubular member 8 and the partition member 16 are also fixed at the same time. That is, the leg 7 presses against the upper end of the elastic tubular member 8, the lower end contacts the upper surface of the outer peripheral portion of the upper partition 17 of the partition member 16, and the lower end of the outer peripheral portion of the lower partition 19 of the partition member 16 is inserted. Since it is supported by the lower flange 21d of the ring 21b, it is eventually sandwiched and fixed between the leg 7 and the lower flange 21d.
[0027]
As shown in FIGS. 2 and 4, an overhang portion 40 is provided on an upper portion of the flange member 3 so that a part of a flange 3 b formed by being bent outward is projected in a radial direction. As shown in FIG. 2, the overhang portions 40 are provided at two positions approximately 60 ° to the left and right across the line L connecting the center O and the pipe portion 13, as seen in FIG. The transverse membrane stopper 11 is directly fixed to the rivets 41, 40.
[0028]
The projecting portion 40 is formed to project from the outer peripheral portion of the original flange 3 b of the flange member 3, and is located inside the flange 38 a of the lower cylindrical member 38. That is, it is formed at a position retracted from the flange 38a so as to avoid an increase in the size of the device. A line M connecting the outsides of the left and right overhangs 40, 40 is substantially straight, and passes through a position on the line L, which is approximately the same as the end of the flange 3b that is the maximum overhang. In addition, the intervals between the overhang portions 40, 40 and the rivets 41, 41 are arbitrary, and are set according to the size of the transverse membrane stopper 11.
[0029]
As shown in FIGS. 3 and 4, the transverse membrane stopper 11 is disposed below the flange 3 b so as to extend along the periphery of the body 3 a of the flange member 3, and the rivets 41, 41 are used in the vertical direction of FIG. It is fixed in a direction parallel to the input direction Z. 4 shows a state before the elastic body member 5 (FIG. 1) is integrated with the flange member 3 and a state before the cylindrical member 4 is connected to the lower cylindrical member 38 (FIG. 1).
[0030]
As is clear from FIG. 4, the horizontal membrane stopper 11 is formed in a substantially arc shape and is formed long in the circumferential direction of the body 3 a (hereinafter, this shape is referred to as “horizontally long”), and the mounting holes provided in the overhanging portions 40, 40. The mounting holes 45, 45 provided in the flange 44 formed in the insert member 43 of the transverse membrane stopper 11 are aligned with each other and are fixed by rivets. The mounting holes 9a and 9b formed in the body portions 3a and 4a are also formed to be horizontally long corresponding to the horizontal membrane stoppers 11.
[0031]
As shown in FIG. 5, the insert member 43 is a metal member having a substantially L-shaped cross section. Are formed continuously and integrally with the flange 44. The insert member 43 is not limited to a metal material and may be a suitable resin material as long as it has a certain degree of rigidity and durability.
[0032]
The lower half of the main body 46 is inserted into the stopper main body 12 and is integrated when the transverse membrane stopper 11 is formed by injection molding or the like. A hole 47 is formed at the lower side of the insert member 43, and the hole 47 strengthens the connection with the stopper body 12, and a ventilation hole 48 is formed through the center of the hole 47. The ventilation hole 48 passes through the central portion of the stopper body 12 through the axis of the pipe 13 and communicates with the transverse membrane working chamber 15.
[0033]
The upper end of the stopper main body 12 fits into the mounting holes 9a and 9b, and the lower end extends only below the lower end of the body 3a and fits only into the mounting hole 9b.
The outermost projection 51 is formed on the surface of the stopper body 12 facing the horizontal membrane working chamber 15, and a large number of projections 52 are formed integrally with the outermost projection 51. A large number of the projections 52 are arranged in a dot shape so as to surround the sheet surface 53 in a ring shape. However, instead of the projection 52, a continuous ring-shaped projection may be formed. One end of a ventilation hole 48 is opened in the seat surface 53.
[0034]
The outermost projection 51 forms a seal that is constantly pressed against the periphery of the lateral membrane 10. However, conversely, the seal protrusion can be made to protrude from the lateral film 10 side. The projections 52 define the outer periphery of the seat surface 53, and the diaphragm 10 is subjected to a stepwise elastic deformation so as to first come into contact with the projections 52 and then to the seat surface 53 when the diaphragm 10 elastically deforms. The ten springs are changed in three stages of a free state, at the time of contact with the projection 52, and at the time of contact with the seat surface 53, to generate a non-linear spring characteristic.
[0035]
A substantially cylindrical insert member 54 is integrally formed with the elastic cylindrical member 8 as a metal core. At positions corresponding to the mounting holes 9a and 9b of the insert member 54, a horizontal hole 55 having the same shape is formed, and a part of the elastic cylindrical member 8 covering the horizontal hole 55 is the horizontal membrane 10. The edge of the horizontal hole 55 is located at a position close to the outermost peripheral projection 51.
[0036]
The elastic cylindrical member 8 is made of an elastic material having excellent heat resistance and gasoline resistance, for example, hydrin rubber, silicon rubber, fluorine rubber, or the like. The non-circular transverse film 10 can be easily formed.
[0037]
The upper part of the insert member 54 forms an inward flange 56 and the lower part forms an outward flange 57. The elastic member of the elastic cylindrical member 8 is also integrally formed around the flange 56 to form an elastic receiving portion 8a, and the leg 7 of the elastic main body 5 is pressed against and adheres to the elastic receiving portion 8a. The joint with the portion 8a is sealed. Note that seal projections 8b and 7a are provided from both members.
[0038]
The lower end 8c of the elastic tubular member 8 is in close contact with the vicinity of the mounting hole 9b in the main body 4a of the tubular member 4 to seal the space between the tubular member 4 and the elastic tubular member 8, and the outer peripheral surface of the upper partition 17 Close to. At this time, the seal projection 8d integrally formed ensures sealing. The stopper body also has a seal projection 8e at the lower end 8c at the contact portion with the lower portion.
[0039]
The outer peripheral portion of the flange 57 overlaps with the upper end flange of the lower cylindrical member 38 and the upper flange 21c of the insert ring 21b, and is caulked and integrated by the caulking portion 4b provided on the flange portion of the tubular member 4.
[0040]
Next, the operation of the present embodiment will be described. First, if the ventilation hole 48 of the pipe portion 13 is opened to the atmosphere to make the elastic deformation of the horizontal membrane 10 free, the horizontal membrane 10 responds to the fluctuation of the internal pressure of the main liquid chamber 20 by the minute vibration input from the first mounting member 1. And elastically deforms freely to absorb changes in the internal pressure of the main liquid chamber 20. Therefore, the whole becomes a low dynamic spring.
[0041]
If there is a larger vibration input, the diaphragm 10 comes into contact with the seat surface 53 and the elastic deformation thereof is regulated, so that the spring of the diaphragm 10 becomes high, and the diaphragm 10 is caused by such a large vibration. Excessive deformation can be prevented to prevent breakage, and the durability of the transverse membrane 10 can be improved.
[0042]
Therefore, a low spring is used for a small vibration input, and a high spring is used for a larger vibration input. Therefore, the spring constant is changed in a non-linear and wide range to change the internal pressure in the main liquid chamber 20. Absorbing the rise, more ideal vibration absorption becomes possible.
[0043]
Further, if the ventilation hole 48 of the pipe portion 13 is connected to a negative pressure source by the switching valve 14a, the diaphragm working chamber 15 becomes a negative pressure, so that the diaphragm 10 adheres to the seat surface 53 and elastic deformation is restricted. Is done. In this state, if there is a vibration input near the resonance frequency of the damping orifice passage 23 or the idle orifice passage 25, since the elastic deformation of the transverse membrane 10 is regulated, the amount of liquid flow to each orifice passage can be increased, and as a result, Thus, the liquid column resonance efficiency in these orifice passages can be increased. In addition, the restraint of the transverse membrane 10 can also be performed only on one of the damping orifice passage 23 and the idle orifice passage 25.
[0044]
At this time, by providing the projection 52, a gap is secured between the horizontal film 10 and the sheet surface 53, and the horizontal film 10 and the outermost peripheral projection 51 are located near the outer peripheral side projection 51 via the concave portion formed between the adjacent projections 52. Since the gap formed between the inner wall and the central portion of the diaphragm working chamber 15 where the ventilation hole 48 is opened can be kept in communication with each other, the occurrence of air pockets at the corners of the diaphragm working chamber 15 is prevented. In addition, it is possible to prevent a change in the capacity of the diaphragm working chamber 15 due to an increase in the temperature of the engine room, thereby preventing a change in the film rigidity of the diaphragm 10. However, when the influence of the generation of the air pool is small, the protrusion 52 may be formed as a loop-shaped ridge that continuously surrounds the periphery of the opening of the ventilation hole 48 instead of the point-like shape.
[0045]
Since the diaphragm 10 in this embodiment uses a part of the elastic tubular member 8 inserted and fixed into the main liquid chamber 20, it is easy to mold even a complicated shape such as a non-circular shape. In addition, both the mounting property and the sealing property are excellent. In addition, since the elastic tubular member 8 is formed separately from the elastic main body 5, only the elastic tubular member 8 can be made excellent in heat resistance and gasoline resistance. Therefore, overall cost can be reduced and durability can be improved.
[0046]
In addition, the elastic body portion 5 and the elastic tubular member 8 are brought into close contact with the seals 7a and 8b, and the upper partition 17 and the elastic tubular member 8 are brought into close contact with the seal projection 8d. . In addition, since a part of the diaphragm stopper 12 is adhered to the diaphragm 10, the elasticity of the diaphragm 10 can be used to tightly seal the gap between the diaphragm stopper 12 and the diaphragm working chamber 15 as a result. Can be sealed securely.
[0047]
Further, since the transverse membrane stopper 11 can be fixed only by directly attaching the flange 44 of the insert member 43 to the overhanging portion 40 formed on the flange 3b of the flange member 3 by the rivets 41, 41, a special mounting seat is provided. Need not be provided by welding, mounting is easy, and assembling accuracy is increased by the amount of no welding. Moreover, since the insert member 43 has a substantially L-shape and a semicircular shape, the rigidity is increased, the degree of deformation is increased, and the rivets 41 can be fixed at only two places.
[0048]
In addition, as shown in FIG. 6, the insert member 43 is further inclined by θ from the state where the cross section is bent at approximately 90 ° to form an obtuse angle, and is deformed to approximately 90 ° at the time of mounting, and is further improved in adhesion. Become. Conversely, the same effect can be obtained if the main body 4a of the tubular member 4 is inclined so that the lower part projects outward. In any case, it is sufficient to fix only the rivets 41 and 41 only.
[0049]
Further, since the stopper body portion 12 and the pipe portion 13 are formed integrally with the transverse membrane stopper 11 in a state where the insert member 43 is inserted, it is not necessary to combine a plurality of members at the time of assembling as in the related art, and the number of parts can be reduced, and the structure can be reduced. And manufacturing is simplified.
[0050]
In addition, since the diaphragm stopper 11 is made of a resin having excellent heat resistance and gasoline resistance, it does not deform in a state where the diaphragm 10 is in contact with the stopper, so that elastic deformation of the diaphragm 10 can be surely regulated. The spring characteristic of the movable film can be made significantly non-linear between the free state and the restricted state. In addition, since the contact with the lateral membrane 10 is no longer the contact between the rubber and the rubber, the abrasion is reduced, the durability is improved, the shape change is small, and the spring characteristics are stabilized. In addition, durability is improved due to excellent heat resistance and gasoline resistance.
[0051]
The invention of the present application is not limited to the above-described embodiment, and can be variously modified. For example, the invention can be applied to various anti-vibration devices other than the engine mount.
[Brief description of the drawings]
FIG. 1 is an entire cross-sectional view of an engine mount according to an embodiment (a cross-sectional view taken along line 1-1 of FIG. 2).
2 is a view in the direction of the arrow Z in FIG. 1; FIG. 3 is a view in the direction of the arrow X in FIG. 1; FIG. 4 is a perspective view showing the mounting of the diaphragm stopper; FIG. 6 is a view showing another embodiment of the insert member.
1: first mounting member, 2: second mounting member, 5: elastic body member, 8: elastic cylindrical member, 9a. 9b: mounting hole, 10: diaphragm, 11: diaphragm stopper, 12: stopper body, 13: pipe, 15: diaphragm working chamber, 16: partition member, 20: main liquid chamber, 21: diaphragm, 22 : Sub liquid chamber, 23: damping orifice passage, 24: common passage, 25: idle orifice passage, 40: overhang, 41: rivet, 43: insert member, 44: flange

Claims

A first attachment member attached to one of the vibration generating side and the vibration receiving side, a second attachment member attached to the other side, and an elastic body member interposed therebetween; A liquid sealing device including a main liquid chamber as a part of a wall, a sub liquid chamber partitioned by the main liquid chamber and a partition member, and covered by a flexible membrane member, and an orifice passage communicating the two liquid chambers. In the vibration device,
A movable film that faces the main liquid chamber and absorbs fluctuations in its internal pressure; a movable film stopper that regulates deformation of the movable film; and a free film that allows the movable film to freely elastically deform with respect to the movable film stopper. State, and an internal pressure control means for changing to a restricted state in which the movable film is brought into close contact with the movable film stopper,
A liquid seal vibration isolator, wherein the movable film stopper is made of a heat-resistant and gasoline-resistant resin material.

2. The liquid ring vibration isolator according to claim 1, wherein the movable film is formed separately from the elastic main body and is formed on a part of an elastic cylindrical member inserted and fixed into the main liquid chamber. apparatus.

The liquid ring vibration isolator according to claim 2, wherein the movable film and the movable film stopper each have a non-circular shape.