JP4361998B2

JP4361998B2 - Anti-vibration device and method for filling liquid into anti-vibration device

Info

Publication number: JP4361998B2
Application number: JP2000049991A
Authority: JP
Inventors: 和善江嶋
Original assignee: Bridgestone Corp
Current assignee: Bridgestone Corp
Priority date: 2000-02-25
Filing date: 2000-02-25
Publication date: 2009-11-11
Anticipated expiration: 2020-02-25
Also published as: JP2001241489A

Description

【０００１】
【発明の属する技術分野】
本発明は、自動車、建設機械、一般産業用機械等へ適用され、エンジン等の振動発生部から車体等の振動受部へ伝達される振動を抑制する液体封入式の防振装置及び、この液体封入式の防振装の液室空間内へ液体を充填するための防振装置への液体充填方法に関するものである。
【０００２】
【従来の技術】
例えば、車両の振動発生部となるエンジンと振動受部となる車体との間にはエンジンマウントとしての防振装置が配設されており、この防振装置はエンジンが発生する振動を吸収し、車体側に伝達される振動を抑制する。このような防振装置としては、例えば、振動発生部からの振動を受けて変形する弾性体と、この弾性体を内壁の一部とする受圧液室と、この受圧液室と制限通路を介して連通すると共に隔壁の一部がダイアフラムにより構成された副液室とを備えた、所謂、液体封入式のものが知られている。この液体封入式の防振装置を車両のエンジンマウントとして適用した場合には、エンジンの作動時にエンジンからの振動により弾性体が変形すると共に、受圧液室と副液室との間に制限通路を通して液体が相互に流動する現象である液柱共振が生じる。これにより、防振装置へ入力したエンジン振動は弾性体の内部摩擦に基づく吸振作用及び液体の粘性抵抗等により吸収されるので、車体へ伝達されるエンジン振動を効果的に抑制できる。
【０００３】
上記のような液体封入式の防振装置を組み立てる際には、通常、組立の最終工程として受圧液室、制限通路及び副液室からなる液室空間内へ水、オイル、グリセリン等の液体が真空注入法により充填封入される。この真空注入法の液体充填工程では、先ず、装置の外殻部から受圧液室内へ貫通した液体注入路の外殻部側の端部に圧力配管を介して真空ポンプ及び給液容器を接続する。ここで、圧力配管の途中には切換弁が配置されており、この切換弁により液体注入路の連通先を真空ポンプ及び給液容器の何れかに切換可能になっている。また給液容器内には防振装置へ供給するための液体が貯えられている。
【０００４】
この後、切換弁により真空ポンプを液体注入路へ連通させて真空ポンプを作動させ、真空ポンプにより受圧液室、制限通路及び副液室からなる液室空間内が所定の真空度に達するまで液室空間内の空気を装置外部へ排気し、液室空間内が所定の真空度に達したならば、切換弁により給液容器を液体注入路へ連通させる。これにより、給液容器内の液体が液室空間内の真空（負圧）の作用により液室空間内へ吸入されて、受圧液室、制限通路及び副液室にそれぞれ液体が充填封入される。
【０００５】
【発明が解決しようとする課題】
しかしながら、上記のような真空注入法による液体充填工程では、真空ポンプにより受圧液室、制限通路及び副液室からなる液室空間内を減圧する際に、副液室内の内部気圧が所定の真空度に達する前に、すなわち副液室内の空気が十分抜けていない状態で、ダイアフラムが副液室の内壁部へ開口する制限通路の開口端部付近に吸着され、ダイアフラムにより制限通路が閉止されてしまったり、制限通路に連通する隙間が他の隙間から切り離されてしまうことがある。この結果、副液室内にはダイアフラムとその内壁部との間に空気が含まれた隙間できるので、このような状態で、給液容器を液体注入路に連通させて給液容器から液室空間内へ液体を吸入させても、副液室内へ隙間なく液体を充填封入できなくなって液室空間内に空気が残ってしまう。このとき、液室空間内に僅かでも空気が残っていると、この空気が液室空間内の圧力変化により容易に圧縮又は膨張することから、受圧液室と副液室との間の液柱共振が抑制されると共に、防振装置全体としてのばね定数が設計値よりも小さくなり、この結果、防振能力が大幅に低下してしまう。
【０００６】
本発明の目的は、上記事実を考慮し、真空注入法により副液室内へ液体を供給する際に、制限通路を通して副液室内を確実に減圧し、副液室内に空気が残らないように液体を充填できる防振装置及び防振装置への液体充填方法に関するものである。
【０００７】
【課題を解決するための手段】
本発明の防振装置は、振動発生部及び振動受部の一方に連結される第１の取付部材と、振動発生部及び振動受部の他方に連結される第２の取付部材と、前記第１の取付部材と前記第２の取付部材との間に配置されて振動発生部からの振動により変形する弾性体と、隔壁の少なくとも一部が前記弾性体により形成され、液体が封入される受圧液室と、前記受圧液室に隣接して設けられ、液体が封入される副液室と、前記受圧液室と前記副液室とを互いに液体が流通可能となるように連通させる制限通路と、前記受圧液室と前記副液室との間に配置されて受圧液室と副液室とを区画する隔壁の少なくとも一部を構成する仕切部材と、前記副液室の隔壁の一部を構成し、前記仕切部材に対向するように配置された膜状のダイアフラムと、前記仕切部材における前記副液室内へ面した受圧面に設けられ、前記制限通路を通して前記副液室内が減圧され、前記仕切部材へ前記ダイアフラムの一部が密着した場合に、前記ダイアフラムの他の一部と前記副液室の内壁部との間に生じる隙間を前記制限通路へ連通させる負圧導入路と、を有するものである。
【０００８】
上記構成の防振装置によれば、仕切部材における副液室内へ面した受圧面に負圧導入路が設けら、制限通路を通して副液室内が減圧され、ダイアフラムの一部が仕切部材へ密着した場合に、前記負圧導入路がダイアフラムの他の一部と副液室の内壁部との間に生じる隙間を制限通路へ連通させることにより、制限通路を通して副液室内を減圧、すなわち制限通路を通して副液室内の空気を排気する際に、副液室内の気圧が低下すると共にダイアフラムが副液室の容積縮小方向へ変形し、ダイアフラムの一部のみが副液室の内壁部へ密着し、ダイアフラムの他の一部と副液室の内壁部との間に隙間ができた場合でも、この隙間を負圧導入路により制限通路へ連通できるので、制限通路を通して副液室内の空気を所要の真空度が得られるまで確実に減圧（排気）できるようになる。従って、所要の真空度まで減圧された副液室へ制限通路を通して液体を供給すれば、液体供給時に副液室内から空気を排気したり液体を加圧したりすることなく、副液室内へ空気が残らないように液体を充填できる。
【０００９】
ここで、仕切部材の副液室へ面した受圧面に副液室内へ突出するように設けられた複数の突起部を設け、この複数の突起部の間に形成される凹状の溝部を負圧導入路とすることが可能である。この場合には、例えば、複数の突起部を仕切部材の一部として一体的に成形すればよいので、装置の部品点数を増やすことなく、副液室内に負圧導入路を設けることができる。
【００１０】
さらに負圧導入路が設けられる仕切部材を、受圧液室と副液室との容積拡縮方向へ弾性的に変形可能とされ、受圧液室及び副液室内の液圧変化に応じて容積拡縮方向へ変形する弾性隔壁、所謂、メンブランとしてもよい。仕切部材をメンブランとすることにより、例えば、大振幅の振動が入力した場合でも受圧液室内の過大な液圧上昇を防止することができるので、動ばね定数の上昇に伴う大振幅の振動に対する減衰能力の低下を抑制できる。
【００１１】
また、本発明の防振装置への液体充填方法は、上記構成のように構成された防振装置における副液室へ液体を充填するための液体充填方法であって、前記受圧液室に接続された負圧発生源により前記制限通路を通して前記副液室内を減圧した後、前記受圧液室に液体供給源を接続して該液体供給源から前記制限通路を通して前記副液室内に液体を供給するものである。
【００１２】
上記構成の防振装置への液体充填方法によれば、負圧発生源を制限通路へ間接的又は直接的に接続し、この負圧発生源により制限通路を通して副液室内を減圧、する際に、副液室内の気圧が低下すると共にダイアフラムが副液室の容積縮小方向へ変形し、ダイアフラムの一部のみが副液室の内壁部へ密着し、ダイアフラムの他の一部と副液室の内壁部との間に隙間ができた場合でも、この隙間を負圧導入路により制限通路へ連通できるので、負圧発生源により制限通路を通して副液室内の空気を所要の真空度が得られるまで確実に減圧（排気）できるようになる。この後、所要の真空度まで減圧された副液室へ液体供給源から制限通路を通して液体を供給すれば、液体供給時に副液室内から空気を排気したり液体を加圧したりすることなく、副液室内へ空気が残らないように液体を充填できる。
【００１３】
【発明の実施の形態】
以下、本発明の実施の形態に係る防振装置を図面に基づいて説明する。
【００１４】
（実施形態の構成）
図１及び図２には、それぞれ本発明の実施の形態に係る液体封入式の防振装置が示されており、図中の符号Ｓは防振装置の中心線である軸心を示し、この軸心に沿った方向を装置の軸方向として以下の説明を行う。
【００１５】
防振装置１０には、図１に示されるように上端部に平板状の頂板金具１２が配置されており、この頂板金具１２の上面には、軸心Ｓに対して外周側にボルト１４及びピン１６がそれぞれ固着されている。頂板金具１２の下面には、下方へ向かって外径が広がるような略円錐台状とされたゴム製の弾性体１８の頂面が加硫接着されている。また頂板金具１２には軸心Ｓに沿って貫通穴２０が穿設されており、この貫通穴２０の上端部には貫通穴２０より大径とされた凹状の座ぐり部２２が形成されている。
【００１６】
弾性体１８の下端部には、図1に示されるように略円筒状とされた樹脂製の支持円筒２４の上端部が連結されている。支持円筒２４には、その円筒部３０の外周面からそれぞれ径方向へ延出する板状とされた一対の脚部２６が一体的に形成されている。一対の脚部２６にはそれぞれ厚さ方向へ貫通する円形の開口部が形成されており、これらの開口部内にはそれぞれリング状のインサート金具２８が埋設固定されている。
【００１７】
支持円筒２４の円筒部３０は軸心Ｓに対して同軸的に配置されており、円筒部３０の内周面には、上部側に上方へ向かって内径が拡がった段差部３２が形成されている。これにより、円筒部３０は段差部３２に対して上部側では下部側に対して薄肉状となっている。
【００１８】
一方、弾性体１８の下部側には、円筒部３０の段差部３２付近に対応する連結部３４が形成されており、この連結部３４の外周部が円筒部３０の段差部３２及びその上部側に接着されている。これにより、弾性体１８が支持円筒２４の円筒部３０へ同軸的に連結固定される。
【００１９】
弾性体１８には、軸心Ｓに沿って弾性体１８を貫通するように中心穴３６が穿設されている。この中心穴３６の上端部は頂板金具１２の貫通穴２０へ連通し、貫通穴２０及び中心穴３６は、後述する受圧液室６６及び副液室８２へ外部から液体を供給するための液体注入路３８を構成している。また弾性体１８の下面中心部には円形の凹部４０が形成されており、この凹部４０の頂面部には、弾性体１８に穿設された中心穴３６の下端部が開口している。
【００２０】
支持円筒２４の円筒部３０内には、段差部３２の下側に薄肉円筒状の金属製の内筒金具４２が挿入されている。内筒金具４２には、下端部付近に外周側へ延出するように屈曲されたフランジ部４４が設けられ、このフランジ部４４の下部側には上部側の部分に対して大径とされた円筒状のかしめ部４６が一体的に形成されている。
【００２１】
内筒金具４２は、その外周面におけるフランジ部４４の上部側を支持円筒２４の円筒部３０の内周面へ密着させ、かつフランジ部４４が全周に亘って円筒部３０内へ埋設されている。これにより、円筒部３０内へ挿入された内筒金具４２は支持円筒２４へ固定される。また弾性体１８の下端部からは薄肉部４８が延出し、この薄肉部４８により内筒金具４２の内周面が被覆されている。
【００２２】
内筒金具４２内には、図1に示されるように薄肉リング状の隔壁板５０が挿入されており、隔壁板５０は弾性体１８下面における凹部４０の周縁部に当接するように配置されている。隔壁板５０の中心部には円形開口５２が形成されており、この円形開口５２の周縁部には、下方へ向かって開いた半円状の断面を有する挟持フランジ部５４が全周に亘って設けられている。
【００２３】
内筒金具４２内には、隔壁板５０の下側に略円筒状の隔壁部材５６が挿入されている。隔壁部材５６の上端部には、内周側へ略直角に屈曲された上側フランジ部５８が一体的に形成されている。この上側フランジ部５８は径方向に沿ってクランク状に屈曲され、その内周部が外周部に対して下方に位置する。ここで、隔壁部材５６は、上側フランジ部５８の外周部を隔壁板５０の下面に当接させている。
【００２４】
隔壁部材５６の頂面部には、上側フランジ部５８の内周側に隔壁板５０の円形開口と略等しい内径の円形開口６０が形成されている。隔壁板５０と隔壁部材５６との間には、それぞれの円形開口５２,６０を閉止するように円板状のメンブランゴム６２が挟持されている。このメンブランゴム６２の上面には、その外周端に沿って隔壁板５０の挟持フランジ部５４の対応する断面半円状の係合部６４が形成されている。
【００２５】
メンブランゴム６２は、隔壁板５０の下面側から係合部６４を挟持フランジ部５４内へ嵌挿しつつ、その外周部が隔壁板５０の挟持フランジ部５４と隔壁部材５６の上側フランジ部５８とにより挟持されている。これにより、メンブランゴム６２は隔壁板５０の円形開口５２及び隔壁部材５６の円形開口６０をそれぞれ閉止するように支持される。また、弾性体１８の凹部４０の下面が隔壁板５０及びメンブランゴム６２により閉止され、この弾性体１８の凹部４０、隔壁板５０及びメンブランゴム６２により囲まれた空間は、弾性体１８の変形に伴って内容積が拡縮する受圧液室６６とされている。
【００２６】
また隔壁部材５６の下端部には、外周側へ略直角に屈曲された下側フランジ部６８が一体的に形成されている。この下側フランジ部６８は径方向に沿ってクランク状に屈曲され、その外周部が内周部に対して下方に位置する。ここで、隔壁部材５６は下側フランジ部６８の外周側端部を弾性体１８の薄肉部４８を介して内筒金具４２のフランジ部４４の下面へ当接させている。これにより、内筒金具４２内において隔壁部材５６及び隔壁板５０がそれぞれ所定の位置決めされる。
【００２７】
隔壁部材５６の外周面と内筒金具４２の内周面との間には、上端部及び下端部がそれぞれ隔壁板５０の外周部及び下側フランジ部６８の内周部により閉止された環状の空間が形成され、この環状の空間は受圧液室６６と後述する副液室とを互いに連通させる制限通路７０とされている。ここで、制限通路７０は周方向における少なくとも１箇所で仕切板（図示省略）により閉止されている。また隔壁板５０の外周部には連通穴７２が穿設されており、この連通穴７２を通して受圧液室６６は制限通路７０へ連通している。
【００２８】
隔壁部材５６の下方には、略円板状とされたゴム製のダイアフラム７４が配置される。ダイアフラム７４には、その中心部に上方へ向かって凸状に湾曲した薄膜状の弾性隔壁部７６が設けられており、この弾性隔壁部７６は隔壁部材５６の下面側を閉止すると共に、隔壁部材５６内に挿入されて頂部付近をメンブランゴム６２の下面へ当接させている。
【００２９】
メンブランゴム６２の下面には、図３に示されるように隔壁部材５６の円形開口６０に面して４個の突起部７８が一体的に形成されている。これらの突起部７８はそれぞれ扇状の軸直角断面を有しており、軸心Ｓを中心とする径方向に沿って互いに等間隔（９０°間隔）となるように対称的に配置されている。これにより、メンブランゴム６２の下面には、互いに隣接する一対の突起部７８に径方向へ延在する２本の溝状の負圧導入路８０が形成されている。これら２本の負圧導入路８０は軸心Ｓにおいて直交するように交差し、全体としては十字状に延在している。ここで、突起部７８の先端面はそれぞれ円形開口６０を通して副液室８２内まで突出している。
【００３０】
隔壁部材５６の内周側には、上面及び下面側がそれぞれメンブランゴム６２及びダイアフラム７４の弾性隔壁部７６により閉止された空間が形成され、この空間は液体が充填される副液室８２とされている。ここで、隔壁部材５６の周壁部には連通穴８４が穿設されており、この連通穴８４を通して副液室８２は制限通路７０へ連通している。従って、受圧液室６６及び副液室８２は、連通穴７２,８４及び制限通路７０を通して互いに繋がっており、これら液室６６,８２内に充填された液体は制限通路７０を通って互いに流通可能になっている。
【００３１】
ダイアフラム７４には、外周部に弾性隔壁部７６に対して肉厚状とされたリブ８６が形成されている。このリブ８６は、内周部が弾性隔壁部７６に対して上方へ突出し、かつ外周部が弾性隔壁部７６に対して下方へ突出するように、径方向に沿ってクランク状に屈曲した断面を有している。
【００３２】
ダイアフラム７４の下側には、略円板状に形成された金属製のキャップ部材８８が配置される。キャップ部材８８には、中心部に下方へ突出するように湾曲した略円錐台状の気室部９０が形成されている。この気室部９０は、ダイアフラム７４の弾性隔壁部７６との間に弾性隔壁部７６の軸方向に沿った弾性変形を可能とする空気室９２を形成している。ここで、キャップ部材８８には、必要に応じて空気室９２を外部へ連通させ、空気室９２内の気圧上昇を抑制するための空気穴が穿設される。
【００３３】
またキャップ部材８８には、気室部９０の外周端部から径方向外側へ延出するリング状のフランジ部９４が形成され、このフランジ部９４の外周部には断面が上方へ向かって開いた略コ字状とされた嵌挿部９６が形成されている。キャップ部材８８はフランジ部９４をダイアフラム７４のリブ８６の下面に当接させている。これにより、ダイアフラム７４はリブ８６が隔壁部材５６の下側フランジ部６８とキャップ部材８８のフランジ部９４とより挟持されて固定される。このとき、ダイアフラム７４の下方へ突出する外周部がキャップ部材８８の嵌挿部９６に嵌挿した状態となり、これにより、副液室８２から大きな液圧を受けた場合でもダイアフラム７４のずれ、脱落等が防止される。
【００３４】
内筒金具４２のかしめ部４６の下端部は、図１に示されるように内周側へ塑性的に変形さ（かしめら）れ、内筒金具４２のかしめ部４６とフランジ部４４とにより隔壁部材５６の下側フランジ部６８、ダイアフラム７４のリブ８６及びキャップ部材８８の嵌挿部９６が軸方向へ重ね合わされた状態で挟持される。これにより、これにより、隔壁板５０、隔壁部材５６、ダイアフラム７４及びキャップ部材８８が支持円筒２４へ固定される。
【００３５】
上記のように構成された防振装置１０は、組立工程の最終段階で受圧液室６６、制限通路７０及び副液室８２からなる液室空間９８（図３参照）内に水、エチレングリコール、シリコンオイル等の液体が充填封入される。この際、液体注入路３８の頂板金具１２側の端部にはニップル１０２が挿入され、このニップル１０２を介して圧力配管１００が接続される。圧力配管１００の途中で配管１０４,１０６に分岐しており、一方の配管１０４には真空ポンプ１０８が接続され、この真空ポンプ１０８と配管１０４の分岐部との間に開閉弁１１０及び真空計１１２が配置されている。また他方の配管１０６には液体が貯えられた給液タンク１１４に接続され、この給液タンク１１４と配管１０６の分岐部との間にも開閉弁１１６が配置されている。
【００３６】
液室空間９８内に液体を充填する際には、先ず、開閉弁１１０が開に、開閉弁１１６が閉として、この状態で真空ポンプ１０８を作動させる。これにより、真空ポンプ１０８が圧力配管１００及び液体注入路３８を通して液室空間９８内の空気を外部へ排気する。このとき、副液室８２内の空気は制限通路７０を通って受圧液室６６内へ流動し、受圧液室６６を経由して真空ポンプ１０８により排気される。
【００３７】
ここで、副液室８２の隔壁における一部を構成するダイアフラム７４の弾性隔壁部７６は、副液室８２の隔壁における他の部分、例えば、メンブランゴム６２と比較して剛性が低い。このため、副液室８２内の空気が排気されて副液室８２内が減圧されると、ダイアフラム７４の弾性隔壁部７６が優先的に副液室８２の容積縮小方向へ変形する。この結果、図４に示されるように弾性隔壁部７６の中央部が実線で示されるようにメンブランゴム６２における突起部７８の下面へ圧着する。このとき、突起部７８は、弾性隔壁部７６の一部が負圧導入路８０内に入り込むような形状に変形し、弾性隔壁部７６により負圧導入路８０が閉止されたり、弾性隔壁部７６が隔壁部材５６の連通穴８４付近の内壁へ密着しないように副液室８２内への突出長（負圧導入路８０の深さ）及び、隣り合う突起部７８との間隔（負圧導入路８０の幅）がそれぞれ設定されている。
【００３８】
従って、図４に示されるように、副液室８２内の負圧の作用によって弾性隔壁部７６の中央部付近がメンブランゴム６２における突起部７８の下面へ密着し、弾性隔壁部７６の外周部と隔壁部材５６との間に隙間ができても、この隙間全体が負圧導入路８０により制限通路７０へ連通する。この結果、液室空間９８を所定の真空度まで減圧する際に、制限通路７０を通して副液室８２全体が所定の真空度まで確実に減圧される。
【００３９】
真空ポンプ１０８は真空計１１２による計測値が所定の真空度に達するまで作動される。ここで、液室空間９８内全体が均一に減圧されているならば、真空計１１２により計測される真空度は液室空間９８内の真空度と誤差範囲内で一致する。真空計１１２の計測値が所定の真空度に達したならば、真空ポンプ１０８を作動停止させ、開閉弁１１０を開状態から閉状態とする。これにより、液室空間９８内は所定の真空度に維持される。
【００４０】
次いで、開閉弁１１６を閉状態から開状態とすると、液室空間９８の真空（負圧）の作用及び、弾性体１８及びダイアフラム７４が容積拡大方向へ復元することによって給液タンク１１４内の液体が液室空間９８内へ吸入され、液室空間９８内に隙間なく液体が充填される。このとき、給液タンク１１４内の液体を特に加圧する必要はないが、静圧により液体の液室空間９８内への移動及び充填が促進されるように給液タンク１１４を防振装置１０より高い位置に設置しておくことが好ましい。
【００４１】
液室空間９８内への液体の充填が完了したならば、圧力配管１００のニップル１０２を液体注入路３８から抜き取り、液体注入路３８の頂板金具１２側の開口部から密閉栓１１８を圧入し、図１に示されるように密閉栓１１８により液体注入路３８を閉止して液体を液室空間９８内に封入する。ここで、密閉栓１１８は先端側が球状とされた軸部１２０と、この軸部１２０の基端側に一体的に設けられた大径の頭部１２２を備えており、軸部１２０の球状部が頂板金具１２の下面側まで挿入されることにより、液体注入路３８からの脱落及び漏洩が防止されるようになっている。
【００４２】
上記のように構成された防振装置１０は脚部２６がそのインサート金具２８内を挿通するボルト（図示省略）により車体状へ締結固定され、エンジン側のブラケットが頂板金具１２上にボルト１４により連結固定されると共に、このボルト１４及びピン１６により相対的に所定の位置関係となるように位置決めされる。
【００４３】
（実施形態の作用）
次に、本実施形態に係る防振装置１０による作用を説明する。
【００４４】
本実施形態の防振装置１０では、頂板金具１２を介してエンジンからの振動が弾性体１８に伝達されると、弾性体１８は吸振主体として作用し、弾性体１８の内部摩擦に基づく吸振作用によって振動が吸収される。これと同時に、弾性体１８の変形に伴って受圧液室６６の内容積が拡縮すると共に、制限通路７０を通して受圧液室６６と副液室８２との間を液体が相互に流通する。このとき、副液室８２の隔壁の一部を構成するダイアフラム７４が容積拡縮方向へ変形し、副液室８２内での液圧上昇が抑制されることから、受圧液室６６内の内容積の拡縮（液圧変化）に追従して受圧液室６６と副液室８２との間で液体が円滑に流通する。この結果、制限通路７０を通過する液体の圧力変化、粘性抵抗等により振動エネルギが吸収されてエンジンから車体側へ伝えられる振動を減衰できる。
【００４５】
また、弾性体１８の剛性、制限通路７０の長さ及び断面積等に対応する周波数域（チューニング周波数域）の振動がエンジンから防振装置１０へ入力した場合には、制限通路７０を通して受圧液室６６と副液室８２との間における液体流通を共振作用（液柱共振）により増幅できることから、防振装置１０によりエンジンから入力するチューニング周波数域の振動を特に効果的に減衰できる。
【００４６】
また、受圧液室６６と副液室８２との間を仕切るメンブランゴム６２がそれぞれの液室６６,８２の容積拡縮方向へ変形可能とされていることから、例えば、大振幅の振動が弾性体１８へ入力し、受圧液室６６の内容積が急激に変化した場合でも、メンブランゴム６２の変形によって受圧液室６６内における過大な液圧上昇を防止することができるので、動ばね定数の上昇に伴う大振幅の振動に対する減衰能力の低下を抑制できる。
【００４７】
一方、本実施形態の防振装置１０の液室空間９８への液体充填時には、メンブランゴム６２の下面に副液室８２内へそれぞれ突出するように４個の突起部７８が形成され、これらの突起部７８の間が負圧導入路８０とされていることにより、液室空間９８内への液体充填時に制限通路７０を通して副液室８２内が減圧され、ダイアフラム７４の一部が突起部７８の下面を含む副液室８２の内壁へ密着し、ダイアフラム７４の他の一部と副液室８２の内壁部との間に隙間ができた場合でも、負圧導入路８０がダイアフラム７４と副液室８２の内壁部との間に生じる隙間を制限通路へ連通させる。
【００４８】
この結果、制限通路７０を通して副液室８２内を減圧、すなわち制限通路７０を通して副液室８２内の空気を排気する際に、副液室８２内の気圧が低下すると共にダイアフラムが副液室の容積縮小方向へ変形し、ダイアフラム７４の一部のみが副液室８２の内壁部へ密着し、ダイアフラム７４の他の一部と副液室８２の内壁部との間に隙間ができた場合でも、この隙間を負圧導入路８０により制限通路７０へ連通できるので、制限通路７０を通して副液室８２内の空気を所要の真空度が得られるまで確実に減圧（排気）できるようになる。従って、所要の真空度まで減圧された副液室８２へ制限通路７０を通して液体を供給すれば、液体供給時に副液室８２内から空気を排気したり供給する液体を加圧したりすることなく、副液室８２内へ空気が残らないように液体を充填できる。
【００４９】
なお、負圧導入路８０は、メンブランゴム６２の下面に複数（４個）の突起部７８を一体成形して設けているが、必ずしも突起部７８間を負圧導入路８０とする必要はなく、メンブランゴム６２の下面に凹状の溝を形成し、この溝を負圧導入路としてもよく、またメンブランゴム６２の複数の部位へ開口するような貫通穴を穿設し、この貫通穴を負圧導入路とするようにしてもよい。
【００５０】
また負圧導入路が設けられる仕切部材は、必ずしも弾性体であるメンブランゴム６２である必要はなく、受圧液室６６と副液室８２との間に設けられる樹脂、金属等からなる仕切部材に負圧導入路を設けてもよい。
【００５１】
【発明の効果】
以上説明したように本発明の防振装置及び防振装置への液体充填方法によれば、真空注入法により副液室内へ液体を供給する際に、制限通路を通して副液室内を確実に減圧し、副液室内に空気が残らないように液体を充填できる。
【図面の簡単な説明】
【図１】本発明の実施の形態に係る防振装置の構成を示す軸方向に沿った断面図である。
【図２】本発明の実施の形態に係る防振装置及び防振装置の液室空間へ液体するための構成を示す軸方向に沿った断面図である。
【図３】本発明の実施の形態に係る防振装置への液室空間への液体充填時に副液室を減圧した状態を示す軸方向に沿った断面図である。
【図４】本発明の実施の形態に係る防振装置におけるメンブランゴムに設けられた突起部を示す斜視図である。
【符号の説明】
１０防振装置
１２頂板金具（取付部材）
１８弾性体
２４支持円筒（取付部材）
３８液体注入路
５０隔壁板
５６隔壁部材
６２メンブランゴム（仕切部材）
６６受圧液室
７０制限通路
７４ダイアフラム
７６弾性隔壁部（ダイアフラム）
７８突起部
８０負圧導入路
８２副液室
９８液室空間
１００圧力配管
１０８真空ポンプ（負圧発生源）
１１４給液タンク（液体供給源）[0001]
BACKGROUND OF THE INVENTION
The present invention is applied to automobiles, construction machines, general industrial machines, etc., and is a liquid-filled vibration isolator that suppresses vibrations transmitted from a vibration generating part such as an engine to a vibration receiving part such as a vehicle body, and the liquid The present invention relates to a liquid filling method for a vibration isolator for filling a liquid chamber space of a sealed vibration isolator.
[0002]
[Prior art]
For example, an anti-vibration device as an engine mount is disposed between an engine that is a vibration generation unit of a vehicle and a vehicle body that is a vibration receiving unit, and the anti-vibration device absorbs vibration generated by the engine, Suppresses vibrations transmitted to the vehicle body. As such an anti-vibration device, for example, an elastic body that is deformed by receiving vibration from a vibration generating unit, a pressure receiving liquid chamber having the elastic body as a part of an inner wall, and the pressure receiving liquid chamber and a restriction passage are used. There is known a so-called liquid-sealed type in which a partition wall is provided with a secondary liquid chamber in which a part of a partition wall is constituted by a diaphragm. When this liquid-filled vibration isolator is applied as an engine mount of a vehicle, the elastic body is deformed by vibration from the engine when the engine is operated, and a restriction passage is provided between the pressure receiving liquid chamber and the sub liquid chamber. Liquid column resonance, which is a phenomenon in which liquid flows mutually, occurs. As a result, the engine vibration input to the vibration isolator is absorbed by the vibration absorbing action based on the internal friction of the elastic body and the viscous resistance of the liquid, so that the engine vibration transmitted to the vehicle body can be effectively suppressed.
[0003]
When assembling a liquid-sealed vibration isolator as described above, normally, as a final process of assembly, liquids such as water, oil, glycerin, etc. enter the liquid chamber space consisting of the pressure receiving liquid chamber, the restriction passage, and the auxiliary liquid chamber. Filled and sealed by vacuum injection. In the liquid filling process of this vacuum injection method, first, a vacuum pump and a liquid supply container are connected to the end of the liquid injection path penetrating from the outer shell portion of the apparatus into the pressure receiving liquid chamber via a pressure pipe. . Here, a switching valve is arranged in the middle of the pressure pipe, and the switching destination of the liquid injection path can be switched to either the vacuum pump or the liquid supply container by this switching valve. A liquid for supplying to the vibration isolator is stored in the liquid supply container.
[0004]
Thereafter, the switching valve connects the vacuum pump to the liquid injection path to operate the vacuum pump, and the liquid is kept until the inside of the liquid chamber space including the pressure receiving liquid chamber, the restriction passage, and the sub liquid chamber reaches a predetermined degree of vacuum. When the air in the chamber space is exhausted to the outside of the apparatus, and the inside of the liquid chamber space reaches a predetermined degree of vacuum, the liquid supply container is connected to the liquid injection path by the switching valve. As a result, the liquid in the liquid supply container is sucked into the liquid chamber space by the action of vacuum (negative pressure) in the liquid chamber space, and the pressure receiving liquid chamber, the restriction passage, and the sub liquid chamber are filled and sealed, respectively. .
[0005]
[Problems to be solved by the invention]
However, in the liquid filling process by the vacuum injection method as described above, when the pressure inside the liquid chamber space including the pressure receiving liquid chamber, the restriction passage, and the sub liquid chamber is reduced by the vacuum pump, the internal pressure in the sub liquid chamber is a predetermined vacuum. Before reaching the limit, that is, when the air in the secondary liquid chamber is not sufficiently removed, the diaphragm is adsorbed near the opening end of the restriction passage that opens to the inner wall of the secondary liquid chamber, and the restriction passage is closed by the diaphragm. In some cases, the gap communicating with the restriction passage may be separated from other gaps. As a result, a gap containing air is formed between the diaphragm and the inner wall portion in the auxiliary liquid chamber, and in this state, the liquid supply container is communicated with the liquid injection path and the liquid chamber space is separated from the liquid supply container. Even if the liquid is sucked in, the liquid cannot be filled and sealed in the auxiliary liquid chamber without any gap, and air remains in the liquid chamber space. At this time, if even a small amount of air remains in the liquid chamber space, the air easily compresses or expands due to a pressure change in the liquid chamber space, so that the liquid column between the pressure receiving liquid chamber and the auxiliary liquid chamber Resonance is suppressed, and the spring constant of the vibration isolator as a whole is smaller than the design value. As a result, the vibration isolating capability is greatly reduced.
[0006]
The object of the present invention is to take the above-mentioned fact into consideration, and when supplying liquid into the secondary liquid chamber by the vacuum injection method, the liquid is surely decompressed through the restriction passage so that no air remains in the secondary liquid chamber. And a liquid filling method for the vibration isolator.
[0007]
[Means for Solving the Problems]
The vibration isolator of the present invention includes a first mounting member connected to one of the vibration generating unit and the vibration receiving unit, a second mounting member connected to the other of the vibration generating unit and the vibration receiving unit, and the first An elastic body disposed between the first mounting member and the second mounting member and deformed by vibration from the vibration generating portion, and a pressure receiving pressure in which at least a part of the partition wall is formed by the elastic body and the liquid is sealed A liquid chamber, a sub-liquid chamber provided adjacent to the pressure-receiving liquid chamber and enclosing the liquid, and a restriction passage communicating the pressure-receiving liquid chamber and the sub-liquid chamber with each other so that the liquid can flow therethrough. A partition member that is disposed between the pressure-receiving liquid chamber and the sub-liquid chamber and forms at least a part of a partition that divides the pressure-receiving liquid chamber and the sub-liquid chamber; and a part of the partition of the sub-liquid chamber Configured and arranged to face the partition member Membranous The diaphragm is provided on a pressure receiving surface facing the sub liquid chamber in the partition member, and when the sub liquid chamber is depressurized through the restriction passage and a part of the diaphragm is in close contact with the partition member, the diaphragm And a negative pressure introduction path that communicates a gap generated between the other part and the inner wall portion of the sub liquid chamber to the restriction passage.
[0008]
According to the vibration isolator having the above configuration, the negative pressure introduction path is provided in the pressure receiving surface facing the sub liquid chamber in the partition member, the sub liquid chamber is depressurized through the restriction passage, and a part of the diaphragm is in close contact with the partition member. In this case, the negative pressure introduction passage communicates with the restriction passage a gap formed between the other part of the diaphragm and the inner wall portion of the auxiliary liquid chamber, thereby reducing the pressure in the auxiliary liquid chamber through the restriction passage, that is, through the restriction passage. When the air in the secondary liquid chamber is exhausted, the pressure in the secondary liquid chamber decreases and the diaphragm deforms in the direction of volume reduction of the secondary liquid chamber, and only a part of the diaphragm is in close contact with the inner wall of the secondary liquid chamber. Even if there is a gap between the other part and the inner wall of the secondary liquid chamber, this gap can be communicated to the restriction passage by the negative pressure introduction passage, so that the air in the secondary liquid chamber is evacuated to the required vacuum through the restriction passage. Sure until the degree is obtained It becomes possible to reduced pressure (exhaust). Therefore, if the liquid is supplied through the restriction passage to the sub liquid chamber whose pressure is reduced to a required degree of vacuum, the air is not exhausted from the sub liquid chamber or pressurized while the liquid is supplied. It can be filled with liquid so that it does not remain.
[0009]
Here, a plurality of protrusions provided so as to protrude into the auxiliary liquid chamber are provided on the pressure receiving surface of the partition member facing the auxiliary liquid chamber, and the concave groove formed between the plurality of protrusions is subjected to negative pressure. It can be an introduction path. In this case, for example, the plurality of protrusions may be integrally formed as a part of the partition member, so that the negative pressure introduction path can be provided in the auxiliary liquid chamber without increasing the number of parts of the apparatus.
[0010]
Further, the partition member provided with the negative pressure introduction path can be elastically deformed in the volume expansion / contraction direction between the pressure receiving liquid chamber and the sub liquid chamber, and the volume expansion / contraction direction according to the change in the liquid pressure in the pressure receiving liquid chamber and the sub liquid chamber. It may be an elastic partition wall that deforms into a so-called membrane. By making the partition member a membrane, for example, even when a large amplitude vibration is input, it is possible to prevent an excessive increase in the fluid pressure in the pressure receiving fluid chamber. A decrease in ability can be suppressed.
[0011]
Further, the liquid filling method for the vibration isolator of the present invention is a liquid filling method for filling the sub liquid chamber with the liquid in the vibration isolator constituted as described above, and is connected to the pressure receiving liquid chamber. After the pressure in the sub liquid chamber is reduced through the restriction passage by the generated negative pressure source, a liquid supply source is connected to the pressure receiving liquid chamber, and liquid is supplied from the liquid supply source into the sub liquid chamber through the restriction passage. Is.
[0012]
According to the liquid filling method for the vibration isolator having the above-described configuration, when the negative pressure generation source is indirectly or directly connected to the restriction passage, and the sub-liquid chamber is decompressed through the restriction passage by the negative pressure generation source. As the atmospheric pressure in the secondary liquid chamber decreases, the diaphragm deforms in the direction of volume reduction of the secondary liquid chamber, and only a part of the diaphragm is in close contact with the inner wall of the secondary liquid chamber, and the other part of the diaphragm and the secondary liquid chamber Even if there is a gap between the inner wall and the inner wall, this gap can be communicated to the restriction passage by the negative pressure introduction path, so that the air in the auxiliary liquid chamber can be obtained through the restriction passage by the negative pressure generation source until the required degree of vacuum is obtained. Reduced pressure (exhaust) can be ensured. After that, if the liquid is supplied from the liquid supply source to the sub liquid chamber whose pressure has been reduced to the required degree of vacuum through the restriction passage, the sub liquid chamber is not evacuated from the sub liquid chamber or pressurized while the liquid is supplied. The liquid can be filled so that no air remains in the liquid chamber.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a vibration isolator according to an embodiment of the present invention will be described with reference to the drawings.
[0014]
(Configuration of the embodiment)
1 and 2 each show a liquid-filled vibration isolator according to an embodiment of the present invention. Reference numeral S in the figure indicates an axis that is the center line of the vibration isolator. The following description will be made with the direction along the axis as the axial direction of the apparatus.
[0015]
As shown in FIG. 1, the vibration isolator 10 is provided with a plate-like top plate 12 at the upper end, and on the top surface of the top plate 12, bolts 14 and Each pin 16 is fixed. The top surface of a rubber elastic body 18 having a substantially truncated cone shape whose outer diameter expands downward is vulcanized and bonded to the lower surface of the top plate metal fitting 12. A through hole 20 is formed in the top plate 12 along the axis S, and a concave counterbore 22 having a larger diameter than the through hole 20 is formed at the upper end of the through hole 20. Yes.
[0016]
As shown in FIG. 1, the lower end of the elastic body 18 is connected to the upper end of a support cylinder 24 made of a resin that has a substantially cylindrical shape. The support cylinder 24 is integrally formed with a pair of leg portions 26 each having a plate shape extending radially from the outer peripheral surface of the cylindrical portion 30. Each of the pair of legs 26 is formed with a circular opening that penetrates in the thickness direction, and a ring-shaped insert fitting 28 is embedded and fixed in each of the openings.
[0017]
The cylindrical portion 30 of the support cylinder 24 is coaxially arranged with respect to the axis S, and a stepped portion 32 having an inner diameter expanding upward is formed on the inner peripheral surface of the cylindrical portion 30 on the upper side. Yes. As a result, the cylindrical portion 30 is thinner on the upper side than the step portion 32 on the lower side.
[0018]
On the other hand, a connecting portion 34 corresponding to the vicinity of the stepped portion 32 of the cylindrical portion 30 is formed on the lower side of the elastic body 18, and the outer peripheral portion of the connecting portion 34 is the stepped portion 32 of the cylindrical portion 30 and its upper side. It is glued to. As a result, the elastic body 18 is coaxially connected and fixed to the cylindrical portion 30 of the support cylinder 24.
[0019]
A central hole 36 is formed in the elastic body 18 so as to penetrate the elastic body 18 along the axis S. The upper end portion of the center hole 36 communicates with the through hole 20 of the top plate 12, and the through hole 20 and the center hole 36 are liquid injection for supplying liquid to the pressure receiving liquid chamber 66 and the sub liquid chamber 82 described later. A path 38 is formed. A circular recess 40 is formed at the center of the lower surface of the elastic body 18, and a lower end portion of a center hole 36 formed in the elastic body 18 is opened at the top surface of the recess 40.
[0020]
A thin cylindrical metal inner metal fitting 42 is inserted into the cylindrical portion 30 of the support cylinder 24 below the stepped portion 32. The inner cylinder fitting 42 is provided with a flange portion 44 that is bent so as to extend to the outer peripheral side in the vicinity of the lower end portion, and the lower portion side of the flange portion 44 has a larger diameter than the upper portion. A cylindrical caulking portion 46 is integrally formed.
[0021]
The inner cylinder fitting 42 is such that the upper side of the flange portion 44 on the outer peripheral surface thereof is in close contact with the inner peripheral surface of the cylindrical portion 30 of the support cylinder 24, and the flange portion 44 is embedded in the cylindrical portion 30 over the entire circumference. Yes. As a result, the inner cylinder fitting 42 inserted into the cylindrical portion 30 is fixed to the support cylinder 24. A thin portion 48 extends from the lower end portion of the elastic body 18, and the inner peripheral surface of the inner cylinder fitting 42 is covered with the thin portion 48.
[0022]
As shown in FIG. 1, a thin ring-shaped partition wall plate 50 is inserted into the inner cylinder fitting 42, and the partition wall plate 50 is disposed so as to contact the peripheral edge of the recess 40 on the lower surface of the elastic body 18. Yes. A circular opening 52 is formed in the central portion of the partition plate 50, and a sandwiching flange portion 54 having a semicircular cross section that opens downward is provided around the entire periphery of the circular opening 52. Is provided.
[0023]
A substantially cylindrical partition member 56 is inserted into the inner cylinder fitting 42 below the partition plate 50. An upper flange portion 58 is integrally formed at the upper end portion of the partition wall member 56 and is bent at a substantially right angle toward the inner peripheral side. The upper flange portion 58 is bent in a crank shape along the radial direction, and an inner peripheral portion thereof is positioned below the outer peripheral portion. Here, the partition member 56 abuts the outer peripheral portion of the upper flange portion 58 on the lower surface of the partition plate 50.
[0024]
A circular opening 60 having an inner diameter substantially equal to the circular opening of the partition plate 50 is formed on the top surface of the partition member 56 on the inner peripheral side of the upper flange portion 58. A disk-shaped membrane rubber 62 is sandwiched between the partition plate 50 and the partition member 56 so as to close the respective circular openings 52 and 60. On the upper surface of the membrane rubber 62, an engaging portion 64 having a semicircular cross section corresponding to the sandwiching flange portion 54 of the partition plate 50 is formed along the outer peripheral end thereof.
[0025]
The membrane rubber 62 is fitted with the engaging portion 64 into the sandwiching flange portion 54 from the lower surface side of the partition plate 50, and the outer peripheral portion thereof is formed by the sandwiching flange portion 54 of the partition plate 50 and the upper flange portion 58 of the partition member 56. It is pinched. Thereby, the membrane rubber 62 is supported so as to close the circular opening 52 of the partition plate 50 and the circular opening 60 of the partition member 56, respectively. Further, the lower surface of the recess 40 of the elastic body 18 is closed by the partition plate 50 and the membrane rubber 62, and the space surrounded by the recess 40, the partition plate 50 and the membrane rubber 62 of the elastic body 18 is deformed by the elastic body 18. Accordingly, a pressure receiving liquid chamber 66 whose internal volume expands and contracts is provided.
[0026]
A lower flange portion 68 that is bent substantially perpendicularly to the outer peripheral side is integrally formed at the lower end portion of the partition wall member 56. The lower flange portion 68 is bent in a crank shape along the radial direction, and the outer peripheral portion thereof is positioned below the inner peripheral portion. Here, the partition member 56 abuts the outer peripheral side end portion of the lower flange portion 68 against the lower surface of the flange portion 44 of the inner cylinder fitting 42 via the thin portion 48 of the elastic body 18. Thereby, the partition member 56 and the partition plate 50 are respectively positioned at predetermined positions in the inner cylinder fitting 42.
[0027]
Between the outer peripheral surface of the partition member 56 and the inner peripheral surface of the inner cylindrical metal fitting 42, an upper end portion and a lower end portion are closed by an outer peripheral portion of the partition plate 50 and an inner peripheral portion of the lower flange portion 68, respectively. A space is formed, and the annular space serves as a restriction passage 70 that allows the pressure receiving liquid chamber 66 and a sub liquid chamber to be described later to communicate with each other. Here, the restriction passage 70 is closed by a partition plate (not shown) at least at one place in the circumferential direction. Further, a communication hole 72 is formed in the outer peripheral portion of the partition plate 50, and the pressure receiving liquid chamber 66 communicates with the restriction passage 70 through the communication hole 72.
[0028]
Below the partition member 56, a rubber diaphragm 74 having a substantially disk shape is disposed. The diaphragm 74 is provided with a thin-film elastic partition wall 76 that is convexly curved upward at the center thereof, and the elastic partition wall 76 closes the lower surface side of the partition wall member 56 and the partition wall member. It is inserted into 56 and the vicinity of the top is brought into contact with the lower surface of the membrane rubber 62.
[0029]
As shown in FIG. 3, four protrusions 78 are integrally formed on the lower surface of the membrane rubber 62 so as to face the circular opening 60 of the partition wall member 56. Each of these protrusions 78 has a fan-shaped cross section perpendicular to the axis, and is symmetrically arranged so as to be equidistant from each other along the radial direction centered on the axis S (90 ° interval). As a result, two groove-like negative pressure introduction paths 80 extending in the radial direction are formed on the lower surface of the membrane rubber 62 in a pair of adjacent projecting portions 78. These two negative pressure introduction paths 80 intersect at an axis S so as to be orthogonal to each other, and extend in a cross shape as a whole. Here, the front end surfaces of the protrusions 78 protrude into the auxiliary liquid chamber 82 through the circular openings 60.
[0030]
On the inner peripheral side of the partition member 56, a space is formed in which the upper surface and the lower surface side are respectively closed by the membrane rubber 62 and the elastic partition wall portion 76 of the diaphragm 74. This space serves as a secondary liquid chamber 82 filled with liquid. Yes. Here, a communication hole 84 is formed in the peripheral wall portion of the partition wall member 56, and the auxiliary liquid chamber 82 communicates with the restriction passage 70 through the communication hole 84. Accordingly, the pressure receiving liquid chamber 66 and the sub liquid chamber 82 are connected to each other through the communication holes 72 and 84 and the restriction passage 70, and the liquid filled in the liquid chambers 66 and 82 can flow through the restriction passage 70. It has become.
[0031]
The diaphragm 74 is formed with ribs 86 that are thicker than the elastic partition wall 76 on the outer periphery. The rib 86 has a cross section bent in a crank shape along the radial direction so that the inner peripheral portion protrudes upward with respect to the elastic partition wall portion 76 and the outer peripheral portion protrudes downward with respect to the elastic partition wall portion 76. Have.
[0032]
A metal cap member 88 formed in a substantially disc shape is disposed below the diaphragm 74. The cap member 88 is formed with a substantially frustoconical air chamber 90 that is curved so as to protrude downward in the center. The air chamber portion 90 forms an air chamber 92 that enables elastic deformation along the axial direction of the elastic partition wall 76 between the diaphragm 74 and the elastic partition wall 76. Here, the cap member 88 is provided with an air hole for allowing the air chamber 92 to communicate with the outside as needed, and suppressing an increase in atmospheric pressure in the air chamber 92.
[0033]
Further, the cap member 88 is formed with a ring-shaped flange portion 94 extending radially outward from the outer peripheral end portion of the air chamber portion 90, and a cross section is opened upward at the outer peripheral portion of the flange portion 94. A fitting insertion portion 96 that is substantially U-shaped is formed. The cap member 88 abuts the flange portion 94 against the lower surface of the rib 86 of the diaphragm 74. As a result, the ribs 86 of the diaphragm 74 are fixed by being sandwiched between the lower flange portion 68 of the partition wall member 56 and the flange portion 94 of the cap member 88. At this time, the outer peripheral portion protruding downward of the diaphragm 74 is in a state of being inserted into the insertion portion 96 of the cap member 88, so that the diaphragm 74 is displaced or dropped even when a large hydraulic pressure is received from the sub liquid chamber 82. Etc. are prevented.
[0034]
As shown in FIG. 1, the lower end portion of the caulking portion 46 of the inner cylinder fitting 42 is plastically deformed (caulking) toward the inner peripheral side, and the partition wall is formed by the caulking portion 46 and the flange portion 44 of the inner cylinder fitting 42. The lower flange portion 68 of the member 56, the rib 86 of the diaphragm 74, and the fitting insertion portion 96 of the cap member 88 are clamped in a state of being overlapped in the axial direction. Thereby, the partition plate 50, the partition member 56, the diaphragm 74, and the cap member 88 are fixed to the support cylinder 24.
[0035]
The vibration isolator 10 configured as described above has water, ethylene glycol, water in the liquid chamber space 98 (see FIG. 3) including the pressure receiving liquid chamber 66, the restriction passage 70, and the auxiliary liquid chamber 82 at the final stage of the assembly process. A liquid such as silicon oil is filled and sealed. At this time, a nipple 102 is inserted into the end of the liquid injection path 38 on the top plate fitting 12 side, and the pressure pipe 100 is connected through the nipple 102. The pressure pipe 100 is branched into pipes 104 and 106, and a vacuum pump 108 is connected to one pipe 104, and an on-off valve 110 and a vacuum gauge 112 are connected between the vacuum pump 108 and a branch portion of the pipe 104. Is arranged. The other pipe 106 is connected to a liquid supply tank 114 in which liquid is stored, and an opening / closing valve 116 is also disposed between the liquid supply tank 114 and a branch portion of the pipe 106.
[0036]
When filling the liquid chamber space 98 with liquid, first, the on-off valve 110 is opened and the on-off valve 116 is closed, and the vacuum pump 108 is operated in this state. As a result, the vacuum pump 108 exhausts the air in the liquid chamber space 98 to the outside through the pressure pipe 100 and the liquid injection path 38. At this time, the air in the auxiliary liquid chamber 82 flows into the pressure receiving liquid chamber 66 through the restriction passage 70 and is exhausted by the vacuum pump 108 via the pressure receiving liquid chamber 66.
[0037]
Here, the elastic partition wall portion 76 of the diaphragm 74 that constitutes a part of the partition wall of the sub-liquid chamber 82 has lower rigidity than other portions of the partition wall of the sub-liquid chamber 82, for example, the membrane rubber 62. For this reason, when the air in the sub liquid chamber 82 is exhausted and the pressure in the sub liquid chamber 82 is reduced, the elastic partition wall 76 of the diaphragm 74 is preferentially deformed in the volume reduction direction of the sub liquid chamber 82. As a result, as shown in FIG. 4, the central portion of the elastic partition wall 76 is pressure-bonded to the lower surface of the protrusion 78 in the membrane rubber 62 as indicated by the solid line. At this time, the protruding portion 78 is deformed into a shape such that a part of the elastic partition wall portion 76 enters the negative pressure introduction passage 80, and the negative pressure introduction passage 80 is closed by the elastic partition wall portion 76, or the elastic partition wall portion 76. Projecting into the auxiliary liquid chamber 82 (depth of the negative pressure introduction path 80) and an interval between the adjacent protrusions 78 (negative pressure introduction path) so that the inner wall of the partition wall member 56 in the vicinity of the communication hole 84 is not closely attached. 80 width) is set.
[0038]
Therefore, as shown in FIG. 4, the vicinity of the central portion of the elastic partition wall 76 is brought into close contact with the lower surface of the protrusion 78 in the membrane rubber 62 by the action of the negative pressure in the sub liquid chamber 82, and the outer peripheral portion of the elastic partition wall 76 Even if there is a gap between the wall member 56 and the partition wall member 56, the entire gap communicates with the restriction passage 70 through the negative pressure introduction path 80. As a result, when the liquid chamber space 98 is depressurized to a predetermined degree of vacuum, the entire sub liquid chamber 82 is reliably depressurized to a predetermined degree of vacuum through the restriction passage 70.
[0039]
The vacuum pump 108 is operated until the value measured by the vacuum gauge 112 reaches a predetermined degree of vacuum. Here, if the entire liquid chamber space 98 is uniformly depressurized, the degree of vacuum measured by the vacuum gauge 112 matches the degree of vacuum in the liquid chamber space 98 within an error range. When the measured value of the vacuum gauge 112 reaches a predetermined degree of vacuum, the vacuum pump 108 is deactivated and the on-off valve 110 is changed from the open state to the closed state. Thereby, the inside of the liquid chamber space 98 is maintained at a predetermined degree of vacuum.
[0040]
Next, when the on-off valve 116 is changed from the closed state to the open state, the liquid in the liquid supply tank 114 is restored by the action of the vacuum (negative pressure) of the liquid chamber space 98 and the elastic body 18 and the diaphragm 74 being restored in the volume expansion direction. Is sucked into the liquid chamber space 98, and the liquid chamber space 98 is filled with liquid without any gap. At this time, it is not necessary to pressurize the liquid in the liquid supply tank 114, but the liquid supply tank 114 is moved from the vibration isolator 10 so that the movement and filling of the liquid into the liquid chamber space 98 are promoted by static pressure. It is preferable to install it at a high position.
[0041]
When the filling of the liquid into the liquid chamber space 98 is completed, the nipple 102 of the pressure pipe 100 is removed from the liquid injection path 38, and the sealing plug 118 is press-fitted from the opening on the top plate fitting 12 side of the liquid injection path 38. As shown in FIG. 1, the liquid injection path 38 is closed by the sealing plug 118, and the liquid is sealed in the liquid chamber space 98. Here, the sealing plug 118 includes a shaft portion 120 having a spherical tip end side, and a large-diameter head portion 122 integrally provided on the proximal end side of the shaft portion 120. Is inserted to the lower surface side of the top plate fitting 12 to prevent the liquid injection passage 38 from dropping off and leaking.
[0042]
In the vibration isolator 10 configured as described above, the leg portion 26 is fastened and fixed to the vehicle body by a bolt (not shown) that passes through the insert fitting 28, and the bracket on the engine side is attached to the top plate fitting 12 by the bolt 14. The bolts 14 and pins 16 are relatively fixed and positioned so as to have a predetermined positional relationship.
[0043]
(Operation of the embodiment)
Next, the effect | action by the vibration isolator 10 which concerns on this embodiment is demonstrated.
[0044]
In the vibration isolator 10 according to the present embodiment, when vibration from the engine is transmitted to the elastic body 18 via the top plate 12, the elastic body 18 acts as a main vibration absorber, and the vibration absorbing action based on the internal friction of the elastic body 18. The vibration is absorbed by. At the same time, the internal volume of the pressure receiving liquid chamber 66 expands and contracts with the deformation of the elastic body 18, and the liquid flows between the pressure receiving liquid chamber 66 and the sub liquid chamber 82 through the restriction passage 70. At this time, the diaphragm 74 constituting a part of the partition wall of the sub liquid chamber 82 is deformed in the volume expansion / contraction direction, and the increase in the liquid pressure in the sub liquid chamber 82 is suppressed, so that the internal volume in the pressure receiving liquid chamber 66 is reduced. The liquid smoothly flows between the pressure receiving liquid chamber 66 and the sub liquid chamber 82 following the expansion / contraction (hydraulic pressure change). As a result, the vibration energy absorbed by the pressure change of the liquid passing through the restriction passage 70, the viscous resistance, etc., and the vibration transmitted from the engine to the vehicle body side can be attenuated.
[0045]
Further, when vibration in a frequency range (tuning frequency range) corresponding to the rigidity of the elastic body 18, the length and cross-sectional area of the restriction passage 70, etc. is input from the engine to the vibration isolator 10, the pressure-receiving liquid is passed through the restriction passage 70. Since the liquid flow between the chamber 66 and the auxiliary liquid chamber 82 can be amplified by a resonance action (liquid column resonance), the vibration in the tuning frequency range input from the engine can be attenuated particularly effectively by the vibration isolator 10.
[0046]
Further, since the membrane rubber 62 partitioning the pressure receiving liquid chamber 66 and the sub liquid chamber 82 can be deformed in the volume expansion / contraction direction of the liquid chambers 66 and 82, for example, large amplitude vibrations are elastic bodies. 18, even if the internal volume of the pressure receiving fluid chamber 66 changes suddenly, an excessive increase in the fluid pressure in the pressure receiving fluid chamber 66 can be prevented by deformation of the membrane rubber 62, so that the dynamic spring constant increases. It is possible to suppress a decrease in the damping capability with respect to large amplitude vibrations.
[0047]
On the other hand, when the liquid chamber space 98 of the vibration isolator 10 according to this embodiment is filled with liquid, the four protrusions 78 are formed on the lower surface of the membrane rubber 62 so as to protrude into the sub liquid chamber 82, respectively. Since the negative pressure introduction path 80 is formed between the protrusions 78, the inside of the auxiliary liquid chamber 82 is decompressed through the restriction passage 70 when the liquid is filled into the liquid chamber space 98, and a part of the diaphragm 74 is partially protruded 78. Even if a gap is formed between the other part of the diaphragm 74 and the inner wall portion of the sub liquid chamber 82, the negative pressure introduction path 80 is connected to the diaphragm 74 and the sub liquid chamber 82. A gap formed between the inner wall of the liquid chamber 82 is communicated with the restriction passage.
[0048]
As a result, when the pressure in the secondary liquid chamber 82 is reduced through the restriction passage 70, that is, when the air in the secondary liquid chamber 82 is exhausted through the restriction passage 70, the atmospheric pressure in the secondary liquid chamber 82 is lowered and the diaphragm is in the secondary liquid chamber. Even when the volume is deformed and only a part of the diaphragm 74 is in close contact with the inner wall portion of the sub-liquid chamber 82, a gap is formed between the other part of the diaphragm 74 and the inner wall portion of the sub-liquid chamber 82. Since the gap can be communicated with the restriction passage 70 by the negative pressure introduction passage 80, the air in the sub liquid chamber 82 can be reliably decompressed (exhausted) through the restriction passage 70 until a required degree of vacuum is obtained. Accordingly, if the liquid is supplied through the restriction passage 70 to the sub-liquid chamber 82 whose pressure has been reduced to the required degree of vacuum, the air is not exhausted from the sub-liquid chamber 82 or the supplied liquid is pressurized without supplying the liquid. The liquid can be filled so that no air remains in the auxiliary liquid chamber 82.
[0049]
The negative pressure introduction path 80 is formed by integrally forming a plurality of (four) protrusions 78 on the lower surface of the membrane rubber 62, but the negative pressure introduction path 80 is not necessarily formed between the protrusions 78. In addition, a concave groove may be formed on the lower surface of the membrane rubber 62, and this groove may be used as a negative pressure introduction path. Also, through holes are formed so as to open to a plurality of portions of the membrane rubber 62. A pressure introduction path may be used.
[0050]
Further, the partition member provided with the negative pressure introduction path does not necessarily need to be the membrane rubber 62 that is an elastic body, and is a partition member made of resin, metal, or the like provided between the pressure receiving liquid chamber 66 and the sub liquid chamber 82. A negative pressure introduction path may be provided.
[0051]
【The invention's effect】
As described above, according to the vibration isolator and the liquid filling method for the vibration isolator of the present invention, when the liquid is supplied into the sub liquid chamber by the vacuum injection method, the sub liquid chamber is surely decompressed through the restriction passage. The liquid can be filled so that no air remains in the auxiliary liquid chamber.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view along the axial direction showing the configuration of a vibration isolator according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view along the axial direction showing a vibration isolator according to an embodiment of the present invention and a configuration for liquid to the liquid chamber space of the vibration isolator.
FIG. 3 is a cross-sectional view along the axial direction showing a state in which the sub liquid chamber is decompressed when the liquid chamber space is filled with liquid in the vibration isolator according to the embodiment of the present invention.
FIG. 4 is a perspective view showing a protrusion provided on the membrane rubber in the vibration isolator according to the embodiment of the present invention.
[Explanation of symbols]
10 Vibration isolator
12 Top plate bracket (Mounting member)
18 Elastic body
24 Support cylinder (mounting member)
38 Liquid injection path
50 Bulkhead plate
56 Bulkhead member
62 Membrane rubber (partition member)
66 Pressure receiving chamber
70 Restricted passage
74 Diaphragm
76 Elastic partition (diaphragm)
78 Projection
80 Negative pressure inlet
82 Secondary liquid chamber
98 Liquid chamber space
100 pressure piping
108 Vacuum pump (negative pressure source)
114 Liquid supply tank (liquid supply source)

Claims

A first attachment member coupled to one of the vibration generator and the vibration receiver;
A second attachment member coupled to the other of the vibration generating portion and the vibration receiving portion;
An elastic body disposed between the first mounting member and the second mounting member and deformed by vibration from a vibration generating unit;
A pressure-receiving liquid chamber in which at least a part of the partition wall is formed of the elastic body and in which a liquid is enclosed;
A sub liquid chamber provided adjacent to the pressure receiving liquid chamber and enclosing a liquid;
A restriction passage that communicates the pressure receiving liquid chamber and the sub liquid chamber with each other so that liquid can flow therethrough;
A partition member disposed between the pressure receiving liquid chamber and the sub liquid chamber and constituting at least a part of a partition partitioning the pressure receiving liquid chamber and the sub liquid chamber;
A part of the partition wall of the sub liquid chamber, and a membrane-like diaphragm arranged to face the partition member;
The partition member is provided on a pressure receiving surface facing the sub liquid chamber, and when the sub liquid chamber is depressurized through the restriction passage and a part of the diaphragm comes into close contact with the partition member, another one of the diaphragms is provided. A negative pressure introduction path that communicates a gap generated between a portion and an inner wall portion of the sub liquid chamber to the restriction passage;
An anti-vibration device comprising:

2. The vibration isolator according to claim 1, wherein the negative pressure introduction path is formed between a plurality of protrusions provided on the pressure receiving surface so as to protrude into the sub liquid chamber.

The partition member is elastically deformable in the volume expansion / contraction direction between the pressure receiving liquid chamber and the sub liquid chamber, and is deformed in the volume expansion / contraction direction according to a change in the liquid pressure in the pressure receiving liquid chamber and the sub liquid chamber. The vibration isolator according to claim 1 or 2, wherein

A liquid filling method for filling a liquid into the sub liquid chamber in the vibration isolator according to claim 1, 2 or 3,
After reducing the pressure in the secondary liquid chamber through the restriction passage by a negative pressure generation source connected to the pressure receiving liquid chamber, a liquid supply source is connected to the pressure receiving liquid chamber and the secondary liquid is passed from the liquid supply source through the restriction passage. A liquid filling method for an anti-vibration device, wherein liquid is supplied into a room.