JP6984947B2

JP6984947B2 - Anti-vibration device

Info

Publication number: JP6984947B2
Application number: JP2018098209A
Authority: JP
Inventors: 勇輝石原; 雄太宮澤; 慶太西川; 龍也堤; 正樹吉田
Original assignee: Bridgestone Corp; Toyota Motor Corp
Current assignee: Bridgestone Corp; Toyota Motor Corp
Priority date: 2018-05-22
Filing date: 2018-05-22
Publication date: 2021-12-22
Anticipated expiration: 2038-05-22
Also published as: JP2019203544A

Description

本発明は、内部に液体が封入された防振装置に関する。 The present invention relates to a vibration isolator in which a liquid is enclosed.

防振装置として、主液室と副液室との間に、主液室と副液室との圧力差に応じて変位する可動部材を備えた液体封入式の防振装置が知られている（例えば、特許文献１参照。）。 As a vibration isolator, a liquid-filled type vibration isolator equipped with a movable member that displaces between the main liquid chamber and the sub liquid chamber according to the pressure difference between the main liquid chamber and the sub liquid chamber is known. (See, for example, Patent Document 1.).

例えば、特許文献１の液体封入式の防振装置では、振動等が入力されると、可動部材の弾性変形による主液室の液圧吸収効果に基づき防振効果が発揮される。 For example, in the liquid-filled anti-vibration device of Patent Document 1, when vibration or the like is input, the anti-vibration effect is exhibited based on the hydraulic pressure absorption effect of the main liquid chamber due to the elastic deformation of the movable member.

ところで、液体封入式の防振装置では、例えば、自動車が段差を乗り越えたり凹凸の大きな路面等を走行して、大きな荷重が入力されると、主液室においてキャビテーションを生じ、異音や振動を発生する場合がある。 By the way, in the liquid-filled anti-vibration device, for example, when an automobile gets over a step or runs on a road surface with large unevenness and a large load is input, cavitation occurs in the main liquid chamber, causing abnormal noise and vibration. It may occur.

しかしながら、特許文献１の防振装置では、主液室と副液室との間にリリーフ弁が設けられており、主液室に一定以上の負圧が生じた際にリリーフ弁が開放され、主液室と副液室の圧力が平衡状態に向かい、キャビテーションの発生が抑制されるように構成されている。 However, in the vibration isolator of Patent Document 1, a relief valve is provided between the main liquid chamber and the auxiliary liquid chamber, and the relief valve is opened when a negative pressure exceeding a certain level is generated in the main liquid chamber. It is configured so that the pressures of the main liquid chamber and the sub liquid chamber move toward the equilibrium state and the occurrence of cavitation is suppressed.

特開２００９−８５３１３号公報Japanese Unexamined Patent Publication No. 2009-8513

従来の防振装置のリリーフ弁では、主液室に過大な負圧が入力した場合に開き難くなってキャビテーションの発生を抑制することが困難になる場合があり、改善の余地があった。 With the relief valve of the conventional anti-vibration device, when an excessive negative pressure is input to the main liquid chamber, it may be difficult to open and it may be difficult to suppress the occurrence of cavitation, and there is room for improvement.

本発明は上記事実を考慮し、過大な負荷が入力した場合のキャビテーションの発生を抑制することのできる防振装置の提供を目的とする。 In consideration of the above facts, an object of the present invention is to provide a vibration isolator capable of suppressing the occurrence of cavitation when an excessive load is input.

請求項１に記載の防振装置は、振動発生部及び振動受部のうちのいずれか一方に連結される第１取付部材と、振動発生部及び振動受部のうちのいずれか他方に連結される第２取付部材と、前記第１取付部材と前記第２取付部材とを弾性的に連結する弾性体と、前記第１取付部材に設けられ、前記弾性体を壁面の一部とする主液室と副液室とを区画する仕切部材と、前記仕切部材の内部に設けられ、前記主液室とは第１連通孔を介して連通し、前記副液室とは第２連通孔を介して連通する収容室と、前記収容室に収容され、前記主液室と前記副液室との圧力差に応じて主液室側と副液室側とに変位する弾性体からなる可動部材と、前記可動部材の前記第１連通孔と対応する箇所に形成され主液室側から副液室側へ貫通する貫通孔と、前記可動部材の前記貫通孔の周縁に沿って設けられ、前記主液室に向けて突出すると共に前記貫通孔から離れる方向に湾曲し、先端が前記収容室の内壁に接触した主液室側凸部と、前記可動部材の前記貫通孔の周縁の全周に渡って設けられ、前記副液室に向けて突出すると共に、前記収容室の内壁に当接して前記貫通孔と前記第２連通孔との間を閉塞する副液室側凸部と、を有する。 The vibration isolator according to claim 1 is connected to a first mounting member connected to either one of a vibration generating portion and a vibration receiving portion, and to any one of the vibration generating portion and the vibration receiving portion. A second mounting member, an elastic body that elastically connects the first mounting member and the second mounting member, and a main liquid provided on the first mounting member and having the elastic body as a part of a wall surface. A partition member for partitioning a chamber and a sub-liquid chamber, which is provided inside the partition member, communicates with the main liquid chamber through a first communication hole, and communicates with the sub-liquid chamber through a second communication hole. A movable member made of an elastic body that is accommodated in the accommodating chamber and is displaced between the main liquid chamber side and the sub-liquid chamber side according to the pressure difference between the main liquid chamber and the sub-liquid chamber. , A through hole formed at a position corresponding to the first communication hole of the movable member and penetrating from the main liquid chamber side to the sub liquid chamber side, and a through hole provided along the peripheral edge of the through hole of the movable member. A convex portion on the main liquid chamber side that protrudes toward the liquid chamber and curves in a direction away from the through hole, and the tip of which contacts the inner wall of the accommodation chamber, and the entire circumference of the peripheral edge of the through hole of the movable member. The sub-liquid chamber side convex portion is provided so as to project toward the sub-liquid chamber and abut on the inner wall of the accommodating chamber to close between the through hole and the second communication hole.

請求項１に記載の防振装置では、衝撃的な荷重が入力し、主液室に過大な負圧が生じると、相対的に副液室側の液体の圧力が主液室側の液体の圧力よりも高くなるので、副液室側の液体が第２連通孔から可動部材を押圧し、可動部材が主液室側に向かって変位し、副液室側凸部が収容室の内壁から離間して第２連通孔が開放される。また、可動部材が変位することで、可動部材に設けられた主液室側凸部は収容室の内壁側へ押圧されて弾性変形する。 In the vibration isolator according to claim 1, when a shocking load is input and an excessive negative pressure is generated in the main liquid chamber, the pressure of the liquid on the secondary liquid chamber side is relatively higher than that of the liquid on the main liquid chamber side. Since the pressure is higher than the pressure, the liquid on the secondary liquid chamber side presses the movable member from the second communication hole, the movable member is displaced toward the main liquid chamber side, and the convex portion on the secondary liquid chamber side is from the inner wall of the accommodation chamber. The second communication hole is opened at a distance. Further, when the movable member is displaced, the convex portion on the main liquid chamber side provided on the movable member is pressed toward the inner wall side of the accommodation chamber and elastically deforms.

これにより、副液室の液体が第２連通孔から収容室、及び第１連通孔を介して主液室へ流れ込み、主液室の液体の圧力と副液室の液体の圧力が平衡状態に向かい、主液室の過大な負圧状態が解消される。
その結果、主液室の液体の圧力がキャビテーションを発生する負圧に到ることが回避されて、キャビテーションに起因する異音や振動が抑制される。 As a result, the liquid in the auxiliary liquid chamber flows from the second communication hole into the main liquid chamber through the accommodation chamber and the first communication hole, and the pressure of the liquid in the main liquid chamber and the pressure of the liquid in the auxiliary liquid chamber are in an equilibrium state. On the other hand, the excessive negative pressure in the main liquid chamber is eliminated.
As a result, the pressure of the liquid in the main liquid chamber is prevented from reaching the negative pressure that causes cavitation, and abnormal noise and vibration caused by cavitation are suppressed.

また、請求項１の防振装置では、主液室側凸部は、貫通孔から離れる方向に湾曲しており、先端が収容室の内壁に当接しているので、可動部材が主液室側に向かって変位すると、湾曲した主液室側凸部は、先端が収容室の内壁に接しながら全体的に倒れこむように曲げ変形する。 Further, in the anti-vibration device of claim 1, the convex portion on the main liquid chamber side is curved in a direction away from the through hole, and the tip is in contact with the inner wall of the accommodation chamber, so that the movable member is on the main liquid chamber side. When displaced toward, the curved main liquid chamber side convex portion is bent and deformed so that the tip of the convex portion is in contact with the inner wall of the accommodating chamber and collapses as a whole.

主液室側凸部は、倒れこむように曲げ変形をするので、バネ特性としては線形域が拡大する傾向となる。即ち、主液室側凸部は、バネ定数が途中で急激に上昇することが抑制されるので、可動部材は変位し易く、その結果、貫通孔と第２連通孔との間が開き易くなる。言い換えれば、貫通孔と第２連通孔との間を塞いでいた可動部材が収容室の内壁から大きく離れ易くなるので、主液室の圧力と副液室の圧力とを迅速に平衡状態に向かわせることができ、従来よりもキャビテーションの発生を抑制する効果を高めることができる。 Since the convex portion on the main liquid chamber side bends and deforms so as to collapse, the linear region tends to expand as a spring characteristic. That is, since the spring constant of the convex portion on the main liquid chamber side is suppressed from suddenly increasing in the middle, the movable member is easily displaced, and as a result, the space between the through hole and the second communication hole is easily opened. .. In other words, the movable member that was blocking the space between the through hole and the second communication hole can be easily separated from the inner wall of the accommodation chamber, so that the pressure in the main liquid chamber and the pressure in the auxiliary liquid chamber quickly move to an equilibrium state. It can be changed, and the effect of suppressing the occurrence of cavitation can be enhanced as compared with the conventional case.

請求項２に記載の発明は、請求項１に記載の防振装置において、前記可動部材には、前記主液室側凸部を前記貫通孔の周方向に複数に分割する切欠が形成されている。 According to the second aspect of the present invention, in the vibration isolator according to the first aspect, the movable member is formed with a notch that divides the main liquid chamber side convex portion into a plurality of portions in the circumferential direction of the through hole. There is.

主液室に向けて突出し、貫通孔から離れる方向に湾曲した主液室側凸部が、貫通孔の周縁に沿って連続していると、主液室側凸部が収容室の内壁に押圧されるにしたがって、主液室側凸部の先端側に周方向の張力が生じ、この張力が、主液室側凸部の貫通孔の径方向外側への変形を抑制するように作用してしまう。 When the main liquid chamber side convex portion protruding toward the main liquid chamber and curved in the direction away from the through hole is continuous along the peripheral edge of the through hole, the main liquid chamber side convex portion presses against the inner wall of the accommodation chamber. As a result, tension is generated in the circumferential direction on the tip side of the convex portion on the main liquid chamber side, and this tension acts to suppress the deformation of the through hole on the convex portion on the main liquid chamber side in the radial direction. It ends up.

そのため、主液室側凸部を、切欠によって貫通孔の周方向に複数に分割することで、主液室側凸部の周方向長さを短くして主液室側凸部に生じる周方向の張力を小さくすることができる。これにより、各々の主液室側凸部が径方向外側に曲げ変形し易くなり、可動部材がより変位し易くなるため、第２連通孔がより開き易くなる。 Therefore, by dividing the main liquid chamber side convex portion into a plurality of pieces in the circumferential direction of the through hole by a notch, the circumferential length of the main liquid chamber side convex portion is shortened and the circumferential direction generated in the main liquid chamber side convex portion is shortened. Tension can be reduced. As a result, each of the main liquid chamber side convex portions is easily bent and deformed radially outward, and the movable member is more easily displaced, so that the second communication hole is more easily opened.

以上説明したように本発明の防振装置によれば、過大な負荷が入力した場合のキャビテーションの発生を抑制することができる、という優れた効果を有する。 As described above, the vibration isolator of the present invention has an excellent effect of suppressing the occurrence of cavitation when an excessive load is input.

本発明の一実施形態に係る防振装置を示す断面図である。It is sectional drawing which shows the vibration isolation device which concerns on one Embodiment of this invention. ブラケットに装着された防振装置を示す斜視図である。It is a perspective view which shows the anti-vibration device attached to a bracket. ブラケットに装着された防振装置を示す断面図である。It is sectional drawing which shows the vibration isolation device attached to the bracket. （Ａ）は通常時のメンブランを示す仕切部材の断面図であり、（Ｂ）はメンブランの円筒部が変位した状態を示す仕切部材の断面図である。(A) is a cross-sectional view of a partition member showing a member in a normal state, and (B) is a cross-sectional view of a partition member showing a state in which the cylindrical portion of the member is displaced. メンブラン、及びメンブラン取付部材を示す斜視図である。It is a perspective view which shows the membrane and the membrane mounting member.

図１乃至図５にしたがって、本発明に係る防振装置の一実施形態について説明する。
図１に示すように、防振装置１０は、振動受部の一例としての車体側に連結される金属製の筒体１２を備えている。筒体１２の内周上部には、ゴム製の弾性体１４が加硫接着されており、第１取付部材の一例としての筒体１２は、この弾性体１４により上方側の開口部が閉鎖されている。 An embodiment of the vibration isolator according to the present invention will be described with reference to FIGS. 1 to 5.
As shown in FIG. 1, the vibration isolator 10 includes a metal cylinder 12 connected to the vehicle body side as an example of a vibration receiving portion. A rubber elastic body 14 is vulcanized and bonded to the upper part of the inner circumference of the tubular body 12, and the tubular body 12 as an example of the first mounting member has an opening on the upper side closed by the elastic body 14. ing.

図２、及び図３に示すように、筒体１２は、車体に連結するブラケット１６の筒部１８に挿入されている。ブラケット１６には、車体に連結する際に用いる脚部２０が設けられている。 As shown in FIGS. 2 and 3, the tubular body 12 is inserted into the tubular portion 18 of the bracket 16 connected to the vehicle body. The bracket 16 is provided with a leg portion 20 used for connecting to the vehicle body.

図１に示すように、この弾性体１４の中央上部には、振動発生部の一例としてのエンジン側に連結される支持体２２が埋設されており、弾性体１４に第２取付部材の一例としての支持体２２が加硫接着されている。支持体２２の上部には、水平方向に延びるエンジン取付部材２４が配置されており、エンジン取付部材２４の孔２６を貫通させたボルト２８を、支持体２２に形成した雌螺子３０に捩じ込むことで、支持体２２にエンジン取付部材２４が固定されている。これにより、エンジンから振動が入力されると、弾性体１４が弾性変形し、支持体２２と筒体１２とが相対移動する。 As shown in FIG. 1, a support 22 connected to the engine side as an example of a vibration generating portion is embedded in the upper center of the elastic body 14, and as an example of a second mounting member in the elastic body 14. Support 22 is vulcanized and bonded. An engine mounting member 24 extending in the horizontal direction is arranged on the upper portion of the support body 22, and a bolt 28 penetrating the hole 26 of the engine mounting member 24 is screwed into a female screw 30 formed in the support body 22. As a result, the engine mounting member 24 is fixed to the support 22. As a result, when vibration is input from the engine, the elastic body 14 is elastically deformed, and the support 22 and the tubular body 12 move relative to each other.

図３に示すように、エンジン取付部材２４には、弾性体からなるストッパ部３１が取り付けられている。ストッパ部３１は、支持体２２の過大変位時に、ブラケット１６の枠部３２に当接して、支持体２２の過大な変位を抑制する。 As shown in FIG. 3, a stopper portion 31 made of an elastic body is attached to the engine mounting member 24. When the support 22 is excessively displaced, the stopper portion 31 comes into contact with the frame portion 32 of the bracket 16 to suppress the excessive displacement of the support 22.

図１に示すように、筒体１２の内部には、弾性体１４の下側に、仕切部材３３が配置されている。図４に示すように、仕切部材３３は、仕切部材本体３４、及びメンブラン取付部材３８を含んで構成されている。図１に示すように、仕切部材本体３４と弾性体１４との間には、エチレングリコール等の液体が充填された主液室４０が形成されている。 As shown in FIG. 1, a partition member 33 is arranged inside the tubular body 12 under the elastic body 14. As shown in FIG. 4, the partition member 33 includes a partition member main body 34 and a membrane mounting member 38. As shown in FIG. 1, a main liquid chamber 40 filled with a liquid such as ethylene glycol is formed between the partition member main body 34 and the elastic body 14.

メンブラン取付部材３８の下側には、ダイヤフラム４２が配置されている。ダイヤフラム４２の外周部分には、金属製の環状の固定部材４６が埋め込まれており、仕切部材本体３４の外周の一部分、及びダイヤフラム４２の外周部分が、筒体１２に加締め固定されている。メンブラン取付部材３８とダイヤフラム４２との間には、エチレングリコール等の液体が充填された副液室４４が形成されている。 A diaphragm 42 is arranged under the member mounting member 38. A metal annular fixing member 46 is embedded in the outer peripheral portion of the diaphragm 42, and a part of the outer peripheral portion of the partition member main body 34 and the outer peripheral portion of the diaphragm 42 are crimped and fixed to the tubular body 12. An auxiliary liquid chamber 44 filled with a liquid such as ethylene glycol is formed between the membrane mounting member 38 and the diaphragm 42.

図４（Ａ）に示すように、仕切部材本体３４の下面には、中央部に、下面側から見て円形とされた下向き第１凹部４８が形成され、下向き第１凹部４８の径方向外側に、下面側から見て円環形状とされた下向き第２凹部５０が形成されており、下向き第１凹部４８と下向き第２凹部５０との間には、下面側から見て円環形状とされた下向き環状凸部５２が形成されている。なお、下向き第２凹部５０には、円環形状とされたシート状の上側ゴム壁５４が接着されている。 As shown in FIG. 4A, a downward first concave portion 48 which is circular when viewed from the lower surface side is formed in the central portion on the lower surface of the partition member main body 34, and the downward outer side of the downward first concave portion 48 in the radial direction. A downward second recess 50 having an annular shape when viewed from the lower surface side is formed, and an annular shape is formed between the downward first recess 48 and the downward second recess 50 when viewed from the lower surface side. The downward annular convex portion 52 is formed. A sheet-shaped upper rubber wall 54 having an annular shape is adhered to the downward second recess 50.

メンブラン取付部材３８は、金属板を円盤状に形成したものであり、仕切部材本体３４の下面に密着して固定されている。メンブラン取付部材３８の中央には、仕切部材本体３４の下向き第２凹部５０の外径と略同一外径とされ、上側から見て円形とされた上向き凹部５６が形成されている。上向き凹部５６には、円形の下側ゴム壁５８が接着されている。 The member mounting member 38 is formed by forming a metal plate in a disk shape, and is fixed in close contact with the lower surface of the partition member main body 34. At the center of the member mounting member 38, an upward recess 56 having a substantially same outer diameter as the outer diameter of the downward second recess 50 of the partition member main body 34 and having a circular shape when viewed from above is formed. A circular lower rubber wall 58 is adhered to the upward recess 56.

下側ゴム壁５８には、仕切部材本体３４の下向き環状凸部５２と対向する位置に、上面側から見て円環形状とされた上向き環状凸部６０が形成されており、上向き環状凸部６０の内側が上向き第１凹部６２、上向き環状凸部６０の外側が上向き第２凹部６４とされている。 On the lower rubber wall 58, an upward annular convex portion 60 having an annular shape when viewed from the upper surface side is formed at a position facing the downward annular convex portion 52 of the partition member main body 34, and the upward annular convex portion is formed. The inside of the 60 is the upward first concave portion 62, and the outside of the upward annular convex portion 60 is the upward second concave portion 64.

ここで、仕切部材本体３４とメンブラン取付部材３８との間において、仕切部材本体３４の下向き第１凹部４８とメンブラン取付部材３８の上向き第１凹部６２との間に第１収容室６６が形成され、仕切部材本体３４の下向き第２凹部５０とメンブラン取付部材３８の上向き第２凹部６４との間に第２収容室６８が形成されている。 Here, between the partition member main body 34 and the membrane mounting member 38, a first storage chamber 66 is formed between the downward first recess 48 of the partition member main body 34 and the upward first recess 62 of the membrane mounting member 38. A second storage chamber 68 is formed between the downward second recess 50 of the partition member main body 34 and the upward second recess 64 of the membrane mounting member 38.

仕切部材本体３４とメンブラン取付部材３８との間には、ゴム等の弾性体にて円盤形状に形成された可動部材の一例としてのメンブラン３６が配置されている。
メンブラン３６の中央部分は、メンブラン３６の中で最も厚肉に形成された円筒部７０とされ、円筒部７０の中心には貫通孔７２が形成されている。メンブラン３６には、円筒部７０の径方向外側に、一定厚さに形成された挟持部７４が設けられており、挟持部７４の径方向外側には、変位部７６が設けられている。円筒部７０、及び変位部７６は、主液室４０と副液室４４との圧力差に応じて変位するように挟持部７４によって弾性的に支持されている。 A membrane 36 as an example of a movable member formed in a disk shape by an elastic body such as rubber is arranged between the partition member main body 34 and the membrane mounting member 38.
The central portion of the membrane 36 is a cylindrical portion 70 formed to be the thickest in the membrane 36, and a through hole 72 is formed in the center of the cylindrical portion 70. The membrane 36 is provided with a holding portion 74 formed to have a constant thickness on the radial outer side of the cylindrical portion 70, and a displacement portion 76 is provided on the radial outer side of the holding portion 74. The cylindrical portion 70 and the displacement portion 76 are elastically supported by the holding portion 74 so as to be displaced according to the pressure difference between the main liquid chamber 40 and the auxiliary liquid chamber 44.

図４（Ａ）、及び図５に示すように、円筒部７０の上面には、貫通孔７２の周囲に、複数の主液室側凸部７８が円筒部７０と一体的に形成されている。主液室側凸部７８は、円筒部７０から先端に向けて、径方向に延びる切欠８０を介して周方向に配置されている。主液室側凸部７８は、側面視で、貫通孔７２から離れる方向に湾曲している。主液室側凸部７８は、言い換えれば、湾曲凸部である。 As shown in FIGS. 4A and 5, a plurality of main liquid chamber side convex portions 78 are integrally formed with the cylindrical portion 70 on the upper surface of the cylindrical portion 70 around the through hole 72. .. The main liquid chamber side convex portion 78 is arranged in the circumferential direction through a notch 80 extending in the radial direction from the cylindrical portion 70 toward the tip end. The convex portion 78 on the main liquid chamber side is curved in a direction away from the through hole 72 in a side view. The main liquid chamber side convex portion 78 is, in other words, a curved convex portion.

図４（Ａ）、及び図５に示すように、変位部７６の両面には、径の異なる複数の環状突起８４が、径方向内側から径方向外側に間隔を開けて形成されている。 As shown in FIGS. 4A and 5, a plurality of annular protrusions 84 having different diameters are formed on both sides of the displacement portion 76 at intervals from the inside in the radial direction to the outside in the radial direction.

図４（Ａ）に示すように、メンブラン３６は、仕切部材本体３４の下向き環状凸部５２とメンブラン取付部材３８の下側ゴム壁５８に形成された上向き環状凸部６０との間に、挟持部７４が挟持されて固定されている。 As shown in FIG. 4A, the membrane 36 is sandwiched between the downward annular protrusion 52 of the partition member main body 34 and the upward annular protrusion 60 formed on the lower rubber wall 58 of the membrane mounting member 38. The portion 74 is sandwiched and fixed.

このようにメンブラン３６が固定された状態で、メンブラン３６の変位部７６は、第２収容室６８の内部に上下方向に変位可能に収容されている。言い換えれば、メンブラン３６の変位部７６は、メンブラン取付部材３８の下側ゴム壁５８と、仕切部材本体３４の上側ゴム壁５４との間に、隙間が形成されるように第２収容室６８の内部に収容されている。 With the membrane 36 fixed in this way, the displacement portion 76 of the membrane 36 is housed inside the second storage chamber 68 so as to be vertically displaceable. In other words, the displacement portion 76 of the membrane 36 has the second accommodating chamber 68 so that a gap is formed between the lower rubber wall 58 of the membrane mounting member 38 and the upper rubber wall 54 of the partition member main body 34. It is housed inside.

また、このようにメンブラン３６が固定された状態で、メンブラン３６の円筒部７０は、第１収容室６６の内部に収容されている。そして、円筒部７０の上面に形成された主液室側凸部７８の先端が、仕切部材本体３４の下向き第１凹部４８の底面に接触しており、円筒部７０の底面が、メンブラン取付部材３８の下側ゴム壁５８に形成された上向き第１凹部６２の底面に接触している。 Further, with the membrane 36 fixed in this way, the cylindrical portion 70 of the membrane 36 is housed inside the first storage chamber 66. The tip of the main liquid chamber side convex portion 78 formed on the upper surface of the cylindrical portion 70 is in contact with the bottom surface of the downward first concave portion 48 of the partition member main body 34, and the bottom surface of the cylindrical portion 70 is a rubber mounting member. It is in contact with the bottom surface of the upward first recess 62 formed in the lower rubber wall 58 of 38.

ここで、仕切部材本体３４の外周面には、周方向に延びる溝８５が形成されており、図１に示すように、この溝８５は、筒体１２によって塞がれてオリフィス通路８６を構成している。オリフィス通路８６は、一端側が、仕切部材本体３４に形成された第１孔８８を介して主液室４０と連通しており、他端側が、仕切部材本体３４に形成された第２孔９０、及びメンブラン取付部材３８に形成された孔９２を介して副液室４４に連通している。したがって、主液室４０と副液室４４とは、オリフィス通路８６を介して常に連通している。 Here, a groove 85 extending in the circumferential direction is formed on the outer peripheral surface of the partition member main body 34, and as shown in FIG. 1, the groove 85 is closed by the tubular body 12 to form an orifice passage 86. is doing. One end of the orifice passage 86 communicates with the main liquid chamber 40 via a first hole 88 formed in the partition member main body 34, and the other end side is a second hole 90 formed in the partition member main body 34. And, it communicates with the auxiliary liquid chamber 44 through the hole 92 formed in the membrane mounting member 38. Therefore, the main liquid chamber 40 and the sub liquid chamber 44 are always in communication with each other via the orifice passage 86.

図１、及び図４（Ａ）に示すように、仕切部材本体３４には、中央に第１連通孔の一例としての孔９３が形成されており、この孔９３を介して主液室４０と第１収容室６６とは常時連通している。メンブラン取付部材３８、及び下側ゴム壁５８には、メンブラン３６の円筒部７０と対向する位置に、副液室４４に連通する複数の第２連通孔の一例としての孔９４が周方向に沿って形成されている。通常時（図４（Ａ）に示す状態）、貫通孔７２と孔９４との間は、円筒部７０の下面が下側ゴム壁５８に接触していることで閉塞されている。なお、メンブラン３６の円筒部７０において、挟持部７４の下面よりも下側に突出している部分が副液室側凸部７０Ａとされている。なお、副液室側凸部７０Ａは、言い換えれば、環状に形成されて、挟持部７４の下面よりも下側に突出している環状凸部である。 As shown in FIGS. 1 and 4A, a hole 93 as an example of the first communication hole is formed in the center of the partition member main body 34, and the main liquid chamber 40 is formed through the hole 93. It is always in communication with the first accommodation room 66. In the membrane mounting member 38 and the lower rubber wall 58, a hole 94 as an example of a plurality of second communication holes communicating with the auxiliary liquid chamber 44 is provided along the circumferential direction at a position facing the cylindrical portion 70 of the membrane 36. Is formed. In the normal state (state shown in FIG. 4A), the space between the through hole 72 and the hole 94 is closed by the lower surface of the cylindrical portion 70 in contact with the lower rubber wall 58. In the cylindrical portion 70 of the membrane 36, the portion protruding below the lower surface of the holding portion 74 is referred to as the auxiliary liquid chamber side convex portion 70A. In other words, the sub-liquid chamber side convex portion 70A is an annular convex portion that is formed in an annular shape and projects downward from the lower surface of the holding portion 74.

また、仕切部材本体３４、及び上側ゴム壁５４には、主液室４０と第２収容室６８とを連通する複数の孔９６が、周方向に沿って形成されている。さらに、メンブラン取付部材３８、及び下側ゴム壁５８には、第２収容室６８と副液室４４とを連通する複数の孔９８が周方向に沿って形成されている。したがって、主液室４０と副液室４４とは、孔９６、第２収容室６８、及び孔９８を介して常に連通している。 Further, a plurality of holes 96 communicating the main liquid chamber 40 and the second accommodating chamber 68 are formed in the partition member main body 34 and the upper rubber wall 54 along the circumferential direction. Further, a plurality of holes 98 that communicate the second accommodating chamber 68 and the auxiliary liquid chamber 44 are formed in the membrane mounting member 38 and the lower rubber wall 58 along the circumferential direction. Therefore, the main liquid chamber 40 and the sub liquid chamber 44 are always in communication with each other through the hole 96, the second storage chamber 68, and the hole 98.

（作用、効果）
本実施形態の防振装置１０は、ブラケット１６に装着され、ブラケット１６の脚部２０を車体に取り付け、エンジン取付部材２４にエンジンを取り付けて用いる。
防振装置１０にエンジンの振動が入力されると、振動は、弾性体１４の内部摩擦に基く抵抗により吸収される他、弾性体１４が変形して主液室４０が拡縮し、主液室４０の液体と副液室４４の液体とがオリフィス通路８６を行き来することで、オリフィス通路８６を流れる液体の通過抵抗、または液柱共振により吸収される。 (Action, effect)
The vibration isolator 10 of the present embodiment is attached to the bracket 16, the legs 20 of the bracket 16 are attached to the vehicle body, and the engine is attached to the engine mounting member 24 for use.
When the vibration of the engine is input to the vibration isolator 10, the vibration is absorbed by the resistance based on the internal friction of the elastic body 14, and the elastic body 14 is deformed to expand and contract the main liquid chamber 40. When the liquid of 40 and the liquid of the auxiliary liquid chamber 44 move back and forth through the orifice passage 86, they are absorbed by the passage resistance of the liquid flowing through the orifice passage 86 or the liquid column resonance.

振動の周波数が上昇して、オリフィス通路８６が目詰まり状態になると、主液室４０の圧力変動によってメンブラン３６が第２収容室６８の内部で振動に応じて変位して主液室４０の圧力上昇が抑えられ、防振装置１０の動バネ定数の上昇が抑えられる。これにより、振動の周波数が上昇しても振動の伝達を低減することができる。 When the frequency of vibration rises and the orifice passage 86 becomes clogged, the membrane 36 is displaced inside the second accommodating chamber 68 according to the vibration due to the pressure fluctuation of the main liquid chamber 40, and the pressure of the main liquid chamber 40 is increased. The rise is suppressed, and the rise of the dynamic spring constant of the vibration isolator 10 is suppressed. This makes it possible to reduce the transmission of vibration even if the frequency of vibration rises.

（衝撃的な荷重の入力）
ところで、自動車が段差を乗り越えたり凹凸の大きな路面等を走行して、防振装置１０に衝撃的な荷重が入力され、支持体２２が急激に上方へ変位すると、主液室４０において、異音や振動の発生原因となるキャビテーションを生じさせる過大な負圧が発生する場合がある。 (Impact load input)
By the way, when an automobile gets over a step or travels on a road surface with large unevenness, a shocking load is input to the vibration isolator 10, and the support 22 is suddenly displaced upward, an abnormal noise is generated in the main liquid chamber 40. Excessive negative pressure that causes cavitation that causes vibration may occur.

主液室４０に過大な負圧が発生する、言い換えると、主液室４０の圧力が過大に減少すると、相対的に、副液室４４の圧力が主液室４０の圧力よりも大きくなり、副液室４４の液体が、メンブラン取付部材３８、及び下側ゴム壁５８に形成された孔９４を介してメンブラン３６の円筒部７０を押し上げ、円筒部７０の底面がメンブラン取付部材３８の下側ゴム壁５８から離間して円筒部７０の底面と下側ゴム壁５８との間に隙間が形成され、貫通孔７２と孔９４とが連通するので、副液室４４の液体が第１収容室６６、及び孔９３を介して主液室４０に流れ込む。これにより、主液室４０の圧力と副液室４４の圧力が平衡状態に向かい、主液室４０の過負圧状態が解消されることから、異音や振動等の原因となるキャビテーションの発生が抑えられる。 An excessive negative pressure is generated in the main liquid chamber 40, in other words, when the pressure in the main liquid chamber 40 is excessively reduced, the pressure in the auxiliary liquid chamber 44 becomes relatively larger than the pressure in the main liquid chamber 40. The liquid in the auxiliary liquid chamber 44 pushes up the cylindrical portion 70 of the membrane 36 through the holes 94 formed in the membrane mounting member 38 and the lower rubber wall 58, and the bottom surface of the cylindrical portion 70 is the lower side of the membrane mounting member 38. A gap is formed between the bottom surface of the cylindrical portion 70 and the lower rubber wall 58 apart from the rubber wall 58, and the through hole 72 and the hole 94 communicate with each other, so that the liquid in the auxiliary liquid chamber 44 can be stored in the first storage chamber. It flows into the main liquid chamber 40 through 66 and the hole 93. As a result, the pressure in the main liquid chamber 40 and the pressure in the auxiliary liquid chamber 44 move toward an equilibrium state, and the excessive negative pressure state in the main liquid chamber 40 is eliminated, so that cavitation that causes abnormal noise and vibration occurs. Is suppressed.

ここで、本実施形態の防振装置１０では、メンブラン３６の円筒部７０が押し上げられることにより、円筒部７０の上部に形成された主液室側凸部７８は、図４（Ａ）に示す状態から図４（Ｂ）に示すように、先端が下向き第１凹部４８の底面を径方向外側に摺動しつつ、全体的に曲がるように弾性変形する。 Here, in the vibration isolator 10 of the present embodiment, the main liquid chamber side convex portion 78 formed on the upper portion of the cylindrical portion 70 by pushing up the cylindrical portion 70 of the membrane 36 is shown in FIG. 4 (A). As shown in FIG. 4B from the state, the tip of the first recess 48 is elastically deformed so as to bend as a whole while sliding downward on the bottom surface of the first recess 48 in the radial direction.

ところで、一例として、円柱状に形成されたゴム等の弾性体が圧縮変形する場合のバネ特性としては、圧縮するにしたがってバネ定数が上がる傾向となり、バネ特性は非線形となる。このため、仮に、円筒部７０の上部に円柱状の主液室側凸部を形成すると、副液室４４の圧力で円筒部７０を下側ゴム壁５８から大きく離間させようとしても、バネ定数が上昇するので円柱状の主液室側凸部を大きく圧縮することが難しい。そのため、円筒部７０を下側ゴム壁５８から大きく離間させて孔９４を大きく開き、大量の液体を副液室４４から主液室４０へ流入させることが難しくなる。 By the way, as an example, when an elastic body such as rubber formed in a columnar shape is compressively deformed, the spring constant tends to increase as it is compressed, and the spring characteristic becomes non-linear. Therefore, if a cylindrical main liquid chamber side convex portion is formed on the upper portion of the cylindrical portion 70, even if the cylindrical portion 70 is largely separated from the lower rubber wall 58 by the pressure of the auxiliary liquid chamber 44, the spring constant It is difficult to greatly compress the columnar convex portion on the main liquid chamber side. Therefore, the cylindrical portion 70 is largely separated from the lower rubber wall 58 to widen the hole 94, and it becomes difficult for a large amount of liquid to flow from the auxiliary liquid chamber 44 into the main liquid chamber 40.

言い換えれば、円筒部７０の上部に円柱状の主液室側凸部を形成した場合、円筒部７０を大きく変位させて孔９４を大きく開こうとしても、円柱状の主液室側凸部を圧縮するにしたがって圧縮反力（円筒部７０を主液室４０側とは反対側へ向かう力）が高くなってしまうので、孔９４は開き難くなり、大量の液体を副液室４４から主液室４０へ流入させることが難しくなる。 In other words, when a cylindrical main liquid chamber side convex portion is formed on the upper part of the cylindrical portion 70, even if the cylindrical portion 70 is largely displaced to open the hole 94 widely, the cylindrical main liquid chamber side convex portion is formed. As the pressure increases, the compression reaction force (the force of the cylindrical portion 70 toward the side opposite to the main liquid chamber 40 side) increases, so that the hole 94 becomes difficult to open, and a large amount of liquid is discharged from the auxiliary liquid chamber 44 to the main liquid. It becomes difficult to flow into the room 40.

一方、本実施形態のように、主液室側凸部７８は断面形状が湾曲しており、曲がるように弾性変形するので、円柱状に形成されたゴム等の弾性体が圧縮変形する場合に比較して、バネ特性を線形に近づけることが出来る。このため、本実施形態のメンブラン３６は、円筒部７０を変位させ易く、円筒部７０を下側ゴム壁５８から大きく離間させて、大量の液体を副液室４４から主液室４０へ流入させることが可能となる。したがって、過大な負圧が主液室４０に生じた場合のキャビテーションの発生を抑制する効果が高いものとなる。 On the other hand, as in the present embodiment, the convex portion 78 on the main liquid chamber side has a curved cross-sectional shape and is elastically deformed so as to bend. Therefore, when an elastic body such as rubber formed in a columnar shape is compressionally deformed. By comparison, the spring characteristics can be made closer to linear. Therefore, in the membrane 36 of the present embodiment, the cylindrical portion 70 is easily displaced, the cylindrical portion 70 is largely separated from the lower rubber wall 58, and a large amount of liquid flows from the auxiliary liquid chamber 44 into the main liquid chamber 40. It becomes possible. Therefore, the effect of suppressing the occurrence of cavitation when an excessive negative pressure is generated in the main liquid chamber 40 is high.

また、本実施形態の主液室側凸部７８は、周方向に連続して形成されておらず、切欠８０によって複数に分割されているので、主液室側凸部７８が曲げ変形する際に生じる周方向の張力を小さくすることができる。これにより、各々の主液室側凸部７８は、分割しない場合に比較して径方向外側に曲げ変形し易くなる。したがって、主液室側凸部７８を分割しない場合に比較してメンブラン３６がより変位し易く、孔９４がより開き易くなっている。 Further, since the main liquid chamber side convex portion 78 of the present embodiment is not continuously formed in the circumferential direction and is divided into a plurality of parts by the notch 80, when the main liquid chamber side convex portion 78 is bent and deformed. The tension in the circumferential direction generated in the can be reduced. As a result, each of the main liquid chamber side convex portions 78 is more likely to be bent and deformed radially outward as compared with the case where they are not divided. Therefore, the membrane 36 is more easily displaced and the holes 94 are more easily opened as compared with the case where the main liquid chamber side convex portion 78 is not divided.

一方、主液室４０の過大な負圧が解消して主液室側凸部７８に押された円筒部７０が下方へ移動すると、図４（Ａ）に示すように、円筒部７０の底面が、下側ゴム壁５８の上向き第１凹部６２に接触し、貫通孔７２と孔９４との間が閉塞される。ここで、円筒部７０が接触する下側ゴム壁５８は、ゴム等の弾性体で形成されているので、円筒部７０が下側ゴム壁５８に接触する際の打音の発生を抑制することができる。 On the other hand, when the excessive negative pressure of the main liquid chamber 40 is eliminated and the cylindrical portion 70 pushed by the main liquid chamber side convex portion 78 moves downward, as shown in FIG. 4A, the bottom surface of the cylindrical portion 70 However, it comes into contact with the upward first recess 62 of the lower rubber wall 58, and the space between the through hole 72 and the hole 94 is closed. Here, since the lower rubber wall 58 with which the cylindrical portion 70 contacts is formed of an elastic body such as rubber, it is possible to suppress the generation of tapping sound when the cylindrical portion 70 contacts the lower rubber wall 58. Can be done.

［その他の実施形態］
以上、本発明の防振装置の一実施形態について説明したが、本発明は、上記に限定されるものでなく、上記以外にも、その主旨を逸脱しない範囲内において種々変形して実施可能であることは勿論である。 [Other embodiments]
Although the embodiment of the anti-vibration device of the present invention has been described above, the present invention is not limited to the above, and can be variously modified and implemented without departing from the gist thereof. Of course there is.

１０…防振装置、１２…筒体（第１取付部材）、１４…弾性体、２２…支持体（第２取付部材）、３３…仕切部材、３６…メンブラン（可動部材）、４０…主液室、４４…副液室、６６…第１収容室（収容室）、７０…円筒部（副液室側凸部）、７０Ａ…副液室側凸部、７２…貫通孔、７８…主液室側凸部、９３…孔（第１連通孔）、９４…孔（第２連通孔）、８０…切欠 10 ... Anti-vibration device, 12 ... Cylindrical body (first mounting member), 14 ... Elastic body, 22 ... Support (second mounting member), 33 ... Partition member, 36 ... Membrane (movable member), 40 ... Main liquid Room, 44 ... Secondary liquid chamber, 66 ... First storage chamber (containment chamber), 70 ... Cylindrical portion (secondary liquid chamber side convex portion), 70A ... Secondary liquid chamber side convex portion, 72 ... Through hole, 78 ... Main liquid Room side convex part, 93 ... hole (first communication hole), 94 ... hole (second communication hole), 80 ... notch

Claims

振動発生部及び振動受部のうちのいずれか一方に連結される第１取付部材と、
振動発生部及び振動受部のうちのいずれか他方に連結される第２取付部材と、
前記第１取付部材と前記第２取付部材とを弾性的に連結する弾性体と、
前記第１取付部材に設けられ、前記弾性体を壁面の一部とする主液室と副液室とを区画する仕切部材と、
前記仕切部材の内部に設けられ、前記主液室とは第１連通孔を介して連通し、前記副液室とは第２連通孔を介して連通する収容室と、
前記収容室に収容され、前記主液室と前記副液室との圧力差に応じて主液室側と副液室側とに変位する弾性体からなる可動部材と、
前記可動部材の前記第１連通孔と対応する箇所に形成され主液室側から副液室側へ貫通する貫通孔と、
前記可動部材の前記貫通孔の周縁に沿って設けられ、前記主液室に向けて突出すると共に前記貫通孔から離れる方向に湾曲し、先端が前記収容室の内壁に接触した主液室側凸部と、
前記可動部材の前記貫通孔の周縁の全周に渡って設けられ、前記副液室に向けて突出すると共に、前記収容室の内壁に当接して前記貫通孔と前記第２連通孔との間を閉塞する副液室側凸部と、
を有する防振装置。 The first mounting member connected to either the vibration generating part or the vibration receiving part, and
A second mounting member connected to either one of the vibration generating part and the vibration receiving part, and
An elastic body that elastically connects the first mounting member and the second mounting member,
A partition member provided on the first mounting member and partitioning a main liquid chamber and a sub liquid chamber having the elastic body as a part of a wall surface.
A storage chamber provided inside the partition member, communicating with the main liquid chamber through the first communication hole, and communicating with the sub liquid chamber through the second communication hole.
A movable member housed in the storage chamber and made of an elastic body that is displaced between the main liquid chamber side and the sub liquid chamber side according to the pressure difference between the main liquid chamber and the sub liquid chamber.
A through hole formed at a position corresponding to the first communication hole of the movable member and penetrating from the main liquid chamber side to the sub liquid chamber side,
It is provided along the peripheral edge of the through hole of the movable member, protrudes toward the main liquid chamber and curves in a direction away from the through hole, and the tip of the movable member is convex toward the main liquid chamber in contact with the inner wall of the accommodation chamber. Department and
The movable member is provided over the entire circumference of the peripheral edge of the through hole, projects toward the auxiliary liquid chamber, and abuts on the inner wall of the accommodation chamber to be between the through hole and the second communication hole. And the convex part on the side of the auxiliary liquid chamber that closes the
Anti-vibration device with.

前記可動部材には、前記主液室側凸部を前記貫通孔の周方向に複数に分割する切欠が形成されている、請求項１に記載の防振装置。 The vibration isolator according to claim 1, wherein the movable member is formed with a notch that divides the convex portion on the main liquid chamber side into a plurality of portions in the circumferential direction of the through hole.