JP3656866B2 - Liquid-filled bush - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid-filled bush that is used, for example, in a suspension device of an automobile and reduces harmful vibrations.
[0002]
[Prior art]
Conventionally, as shown in FIGS. 8 and 9, liquid-filled bushes used for automobile suspensions are known. The liquid-filled bushing is interposed between the main shaft fitting 101, the outer cylinder fitting 104 coaxially disposed on the outer side of the main spindle fitting 101, and the main shaft fitting 101 and the outer cylinder fitting 104. The rubber elastic body 103 having the concave portions forming the main liquid chamber 142 and the sub liquid chamber 143 on both sides in the radial direction with the main shaft fitting 101 interposed therebetween, and the main shaft fitting 101 are fixed to each other. A stopper member 105 that has a first stopper portion 151 that protrudes into the liquid chamber 142 and a second stopper portion 152 that protrudes into the sub-liquid chamber 143, and restricts a relative displacement between the main shaft fitting 101 and the outer cylinder fitting 104 beyond a predetermined level; , And a low-viscosity liquid L enclosed in the main liquid chamber 142 and the sub liquid chamber 143.
[0003]
In this case, in the main liquid chamber 142, a first orifice passage having a U-shaped cross section extending in a direction crossing the radial direction (x direction in FIG. 9) between the wall surface of the main liquid chamber 142 and the first stopper portion 151. 153 is formed, and in the secondary liquid chamber 143, a second U-shaped cross section extending in the radial direction (x direction in FIG. 9) between the wall surface of the secondary liquid chamber 143 and the second stopper portion 152. An orifice passage 154 is formed.
[0004]
For example, the liquid-filled bush is used by fixing the main shaft fitting 101 to the support member on the vehicle body side and press-fitting the outer cylinder fitting 104 into the fitting hole of the attachment member on the wheel side.
When vibration is input between the main shaft fitting 101 and the outer cylinder fitting 104, it flows in the main liquid chamber 142 and the sub liquid chamber 143 in accordance with the elastic action of the rubber elastic body 103 and the elastic deformation of the rubber elastic body 103. The harmful vibration is effectively damped by the liquid column resonance action of the low viscosity liquid L. That is, when vibration in the x direction is input between the main shaft fitting 101 and the outer cylinder fitting 104, the low-viscosity liquid L in the main liquid chamber 142 flows through the first orifice passage 153 to cause a liquid column resonance action. At the same time, the low-viscosity liquid L in the auxiliary liquid chamber 153 flows through the second orifice passage 154 to cause a liquid column resonance action, and the harmful vibration is attenuated. In this case, the frequency of harmful vibration to be reduced is appropriately tuned according to the length distance and the cross-sectional area of the first orifice passage 153 and the second orifice passage 154.
[0005]
[Problems to be solved by the invention]
Incidentally, the above-described fluid-filled bushing, for example, as road noise countermeasure, when set to the bottom of the vibration transmitting force medium and high frequency range (around 250H _Z) is formed, negative occurs at the anti-resonance, the reduction The vibration transmission force in the region other than the target frequency region is amplified. On the other hand, the muffled sound countermeasures, setting to lower the dynamic spring constant of 80～100H _Z, near 250H _Z is a frequency range of road noise level of the dynamic spring constant at the anti-resonance becomes high. Therefore, in the liquid-filled bush having the above-described structure, it has been difficult to achieve both vibration reduction in different frequency regions.
[0006]
The present invention has been devised in view of the above circumstances, and an object to be solved is to provide a liquid-filled bush capable of absorbing vibrations in two different frequency regions.
[0007]
[Means for Solving the Problems]
The invention according to claim 1, which solves the above problem, includes a main shaft bracket, an outer cylinder fitting coaxially disposed on the outer side of the main shaft bracket, and a space between the main shaft bracket and the outer cylinder bracket. The rubber elastic body having a recess that forms a main liquid chamber and a sub liquid chamber on both sides in the radial direction with the main shaft bracket interposed therebetween, and being fixed to the main shaft bracket, A stopper member that has a first stopper portion projecting into the main liquid chamber and a second stopper portion projecting into the sub liquid chamber and restricts a relative displacement in the radial direction between the main shaft fitting and the outer cylinder fitting; In a liquid-filled bush comprising a main liquid chamber and a low-viscosity liquid sealed in the sub-liquid chamber, both the axial side surfaces and the tip surface of the first stopper portion and the rubber elasticity facing these surfaces formed between the annular side wall portion and the inner peripheral surface of the outer cylinder metal fitting body And the cross-sectional area of the first orifice passage extending in a direction transverse to the direction, the second out of both axial side surfaces and tip end surface and the annular side wall portion and the outer cylindrical member of the rubber elastic body opposite to these surfaces of the stopper portion The cross-sectional area of the second orifice passage formed between the peripheral surface and extending in the direction crossing the radial direction is set to be different, and is based on the cross-sectional area of the first orifice passage and the cross-sectional area of the second orifice passage In other words , it is tuned to absorb vibration in two different frequency ranges.
[0008]
According to a second aspect of the present invention, there is provided a main shaft bracket, an outer cylinder bracket coaxially disposed on the outer side of the main shaft bracket, and an interposition between the main shaft bracket and the outer cylinder bracket. And a rubber elastic body having recesses that form a main liquid chamber and a sub liquid chamber on both sides in the radial direction with the main shaft fitting interposed therebetween, and is fixed to the main shaft fitting, and is attached to the main liquid chamber. A stopper member that has a first stopper portion that protrudes and a second stopper portion that protrudes into the sub-liquid chamber and restricts the relative displacement in the radial direction between the main shaft fitting and the outer cylinder fitting, the main liquid chamber, and the In a liquid-filled bush including a low-viscosity liquid sealed in a sub liquid chamber, both side surfaces and tip surfaces in the axial direction of the first stopper portion, and an annular side wall portion of the rubber elastic body facing these surfaces and a direction transverse to the radial direction formed between the inner peripheral surface of the outer cylinder metal fitting Extending the length distance of the first orifice passage, the inner peripheral surface of the axial side surfaces of the second stopper portion and the distal end face and the annular side wall portion and the outer cylindrical member of the rubber elastic body opposite to these surfaces The length distance of the second orifice passage extending in the direction crossing the radial direction formed therebetween is set to be different from the length distance of the first orifice passage and the length distance of the second orifice passage. A means of being tuned so as to absorb vibration in two different frequency ranges is adopted.
[0009]
The invention described in claim 3 employs means in which the low-viscosity liquid has a kinematic viscosity of 100 cst or less in the liquid-filled bush according to claim 1 or 2.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1
FIG. 1 is a cross-sectional view taken along the axial direction of the liquid-filled bush according to the present embodiment, and FIG. 2 is a cross-sectional view taken along the direction perpendicular to the axis of the liquid-filled bush.
[0011]
The liquid-filled bush according to this embodiment includes a main shaft bracket 1, an intermediate cylinder fitting 2 coaxially disposed on the outer side of the main shaft fitting, and a main shaft fitting 1 and the intermediate cylinder fitting 2 interposed therebetween. The rubber elastic body 3 which is integrally connected and has a pair of concave portions on both sides in the radial direction across the main shaft fitting 1 and the concave portion of the rubber elastic body 3 which is coaxially disposed on the outer side of the intermediate cylindrical fitting 2 are closed. The outer cylinder fitting 4 that forms the main liquid chamber 42 and the sub liquid chamber 43, the first stopper portion 51 that is fixed to the main shaft fitting 1 and protrudes into the main liquid chamber 42, and the second stopper portion 52 that protrudes into the sub liquid chamber 43. The main component is a stopper member 5 that restricts relative displacement between the main shaft fitting 1 and the outer cylindrical fitting 2 and a low-viscosity liquid L enclosed in the main liquid chamber 42 and the auxiliary liquid chamber 43. Has been.
[0012]
The main shaft fitting 1 is formed in a pipe shape from metal.
The intermediate cylindrical metal fitting 2 includes a pair of ring portions 21 and 21 positioned at both ends in the axial direction, and two window portions that are bridged between the ring portions 21 and 21 and arranged in the circumferential direction together with the ring portions 21 and 21. The two cross-linking portions 22 and 22 are divided and formed integrally with metal.
[0013]
The rubber elastic body 3 is vulcanized and bonded between the inner peripheral surface of the intermediate cylindrical metal fitting 2 and the outer peripheral surface of the main shaft metal fitting 1, and integrally connects them. The rubber elastic body 3 corresponds to a pair of annular side walls 31, 31 formed at both ends in the axial direction corresponding to the ring portions 21, 21 of the intermediate cylindrical fitting 2, and to the bridge portions 22, 22. It has a pair of arm-shaped partition walls 32 and 32 that extend in the axial direction and bisect the space between both annular side walls 31 and 31. As a result, the rubber elastic body 3 has two recesses which are defined by the annular side wall portions 31 and 31 and the arm-shaped partition wall portions 32 and 32 and open to the window portion of the intermediate cylindrical metal fitting 2 with the spindle metal fitting 1 interposed therebetween. It is formed on both sides in the direction.
[0014]
The outer cylinder fitting 4 is formed of a metal in a cylindrical shape, and a seal rubber layer 41 is vulcanized and bonded to the inner peripheral surface thereof. The outer cylinder fitting 4 is mounted by drawing the outer side of the intermediate cylinder fitting 2, whereby the concave portion of the rubber elastic body 3 is closed and the main liquid chamber 42 in which the low-viscosity liquid L is sealed and A sub liquid chamber 43 is formed. As the low-viscosity liquid L enclosed in the main liquid chamber 42 and the sub liquid chamber 43, for example, a liquid having a kinematic viscosity of 100 cst or less such as water or glycol is used.
[0015]
The stopper member 5 has a central hole penetrating in the thickness direction in the central portion thereof, and the outer peripheral shape is formed in a substantially oval shape. The stopper member 5 is fitted and fixed to the central portion of the outer peripheral surface of the main shaft 1 through the central hole. Has been. One end of the stopper member 5 in the longitudinal direction has a first stopper portion 51 that protrudes into the main liquid chamber 42 and has a tip end surface covered with a buffer rubber layer 51a. It has the 2nd stopper part 52 which protruded in 43 and the front end surface was coat | covered with the buffer rubber layer 52a. The tip portions of the first stopper portion 51 and the second stopper portion 52 are formed in an arc shape corresponding to the inner peripheral surfaces of the opposing seal rubber layer 41 (wall surfaces of the main liquid chamber 42 and the sub liquid chamber 43). .
[0016]
As a result, as shown in FIGS. 1 and 2, both the axial side surfaces and the front end surface of the first stopper portion 51 projecting into the main liquid chamber 42 and the wall surface (rubber elasticity of the main liquid chamber 42 facing these surfaces). Between the annular side wall portions 31 and 31 of the member 3 and the sealing rubber layer 41 bonded to the inner peripheral surface of the outer cylindrical metal fitting 4, it extends in a direction transverse to the radial direction (x direction in FIG. 2) in the cross section perpendicular to the axis . A first orifice passage 53 having a U-shaped cross section (see FIG. 1) is formed . Further, both axial side surfaces and the front end surface of the second stopper portion 52 projecting into the secondary liquid chamber 43 and the wall surfaces of the secondary liquid chamber 43 facing these surfaces (the annular side wall portions 31 and 31 of the rubber elastic member 3 and the outside). A U-shaped cross section (see FIG. 1) extending in a direction transverse to the radial direction (x direction in FIG. 2) in the cross section perpendicular to the axis between the seal rubber layer 41 and the inner peripheral surface of the tubular metal fitting 4 ) . Two orifice passages 54 are formed.
[0017]
The first orifice passage 53 and the second orifice passage 54 have two different desired frequencies by making the thickness dimension A ₁ of the first stopper portion 51 different from the thickness dimension A ₂ of the second stopper portion 52. The cross-sectional areas are set to be different so as to absorb vibration in the region. That is, the first orifice passage 53 has a width dimension B ₁ between the first stopper portion 51 and the annular side walls 31, 31 of the rubber elastic body 3, so that the second stopper portion 52 and the annular side walls 31, 31 of the rubber elastic body 3. It is set smaller than the width B ₂ between, are tuned to reduce vibration of the 200H _Z below the low frequency range. The second orifice passage 54 is tuned so as to reduce vibration of the medium and high frequency region near 300H _Z.
[0018]
The liquid filled bushing of the present embodiment configured as described above, for example, fixes the main shaft bracket 1 to the support member on the vehicle body side and press-fits the outer cylinder bracket 4 into the fitting hole of the mounting member on the wheel side. To be used.
When vibration is input between the main shaft fitting 1 and the outer cylinder fitting 4, it flows in the main liquid chamber 42 and the sub liquid chamber 43 in accordance with the elastic action of the rubber elastic body 3 and the elastic deformation of the rubber elastic body 3. The harmful vibration is effectively damped by the liquid column resonance action of the low viscosity liquid L. That is, when a vibration in the radial direction (the x direction in FIG. 2) is input between the main shaft fitting 1 and the outer cylinder fitting 4, the liquid column of the low-viscosity liquid L flowing in the first orifice passage 53 in the main liquid chamber 42. the resonance effect, the vibration of the following low-frequency range 200H _Z is effectively damped. Further, the vibration of the middle and high frequency region near 300H _Z to anti-resonance occurs, it is effectively damped by the liquid column resonance of the low viscosity liquid L flowing through the second orifice passage 54 in the auxiliary liquid chamber within 43. Thereby, vibration reduction in two different frequency regions is achieved.
[0019]
As described above, according to the liquid filled bushing of the present embodiment, the cross-sectional area of the first orifice passage 53 of the main liquid chamber 42 and the cross-sectional area of the second orifice passage 54 of the sub liquid chamber 43 are made different. Since the low-viscosity liquid L flowing in the first orifice passage 53 and the second orifice passage 54 is tuned so as to absorb vibrations in two different frequency regions by the liquid column resonance action , in the two different frequency regions. Vibration can be effectively absorbed.
When the characteristics of the liquid-filled bush of this embodiment were examined, the results shown by the solid line in FIG. 3 were obtained. 3 indicates the characteristics of the conventional liquid-filled bush shown in FIGS. 8 and 9 (the first orifice passage 153 and the second orifice passage 154 have the same cross-sectional area). As apparent from FIG. 3, fluid-filled bushing of this embodiment, a 200H _Z below the low frequency range, the vibration reduction at 300H _Z middle and high frequency regions different two frequency region near where the anti-resonance occurs It can be seen that is compatible.
[0020]
The liquid-filled bushing of the above embodiments, by varying the thickness dimension A ₁ of the first stopper portion 51 and a thickness dimension A ₂ of the second stopper portion 52, the cross-sectional area of the first orifice passage 53 When it and the cross-sectional area of the second orifice passage 54 is configured differently, the fluid-filled bushing so shown in FIG. 4, the thickness a ₃ of the same of the first stopper portion 51a and the second stopper portion 52a to, annular side wall portion 31a that faces the first stopper portion 51a, and the thickness C ₁ of 31a, annular side wall portion 31b facing the second stopper portion, by making the thickness dimension C ₂ of 31b, The cross-sectional area of the first orifice passage 53a may be different from the cross-sectional area of the second orifice passage 54a.
[0021]
[Embodiment 2]
FIG. 5 is a cross-sectional view along the axial direction of the liquid-filled bush according to this embodiment, and FIG. 6 is a cross-sectional view along the direction perpendicular to the axis of the liquid-filled bush.
The liquid-filled bush of the present embodiment has the same basic structure as that of the first embodiment, and the structure of the first office passage 63 and the second office passage 64 is different due to the difference in the structure of the stopper member 6. Just do it. Therefore, the spindle metal fitting 1, the intermediate cylinder fitting 2, the rubber elastic body 3, the outer cylinder fitting 4, the low-viscosity liquid L, and the like, which are members common to the liquid-filled bushing of the first embodiment, are given the same reference numerals for detailed description. Omitted and the differences will be mainly described.
[0022]
The stopper member 6 of the present embodiment has a central hole penetrating in the thickness direction at a substantially central portion thereof, and the outer peripheral shape is formed in a substantially oval shape. The central hole is formed in the central portion of the outer peripheral surface of the main shaft 1. It is fixed by insertion. The stopper member 6 protrudes into the main liquid chamber 42 and has a front end surface covered with a buffer rubber layer 61a. The stopper member 6 protrudes into the sub liquid chamber 43 and the front end surface is covered with a buffer rubber layer 62a. And a second stopper portion 62. The tip portions of the first stopper portion 61 and the second stopper portion 62 are formed in an arc shape corresponding to the inner peripheral surfaces (wall surfaces of the main liquid chamber 42 and the sub liquid chamber 43) of the opposing seal rubber layer 41. .
[0023]
As a result, as shown in FIGS. 5 and 6, both the axial side surfaces and the front end surface of the first stopper portion 61 projecting into the main liquid chamber 42 and the wall surfaces (rubber elasticity of the main liquid chamber 42 facing these surfaces). Between the annular side wall portions 31 and 31 of the member 3 and the seal rubber layer 41 bonded to the inner peripheral surface of the outer cylindrical metal member 4 ), it extends in a direction transverse to the radial direction (x direction in FIG. 6) in the cross section perpendicular to the axis . A first orifice passage 63 having a U-shaped cross section (see FIG. 5) is formed. Further, both side surfaces and the front end surface of the second stopper portion 62 projecting into the secondary liquid chamber 43 and the wall surfaces of the secondary liquid chamber 43 facing these surfaces (the annular side wall portions 31 and 31 of the rubber elastic member 3 and the outside). Between the seal rubber layer 41 bonded to the inner peripheral surface of the cylindrical metal fitting 4 ), a U-shaped cross section (see FIG. 5) extending in a direction transverse to the radial direction (x direction in FIG. 6) in the cross section perpendicular to the axis . A two-orifice passage 64 is formed.
[0024]
The first orifice passage 63 and the second orifice passage 64 are set to have different length distances and cross-sectional areas so as to absorb vibrations in two target different frequency regions. That is, since the width dimension W ₁ of the first stopper portion 61 is set larger than the thickness dimension W ₂ of the second stopper portion 52, the length distance of the first orifice passage 63 is larger than that of the second orifice passage 64. Is also set to be long.
[0025]
In addition, the gap dimension D ₁ between the protruding front end surface of the first stopper portion 61 and the inner peripheral surface (wall surface of the main liquid chamber 42) of the seal rubber layer 41 facing the first stopper portion 61 is equal to the protruding front end surface of the second stopper portion 62. The first orifice passage 63 has a cross-sectional area that is smaller than the gap dimension D ₂ between the inner circumferential surface of the seal rubber layer 41 (the wall surface of the sub liquid chamber 43) and the seal rubber layer 41. It is set to be smaller than the two orifice passage 64.
[0026]
Thus, the first orifice passage 63 is tuned so as to reduce vibration of the 180H _Z below the low frequency range, the second orifice passage 54 is tuned so as to reduce vibration of the medium and high frequency region near 250H _Z ing.
The liquid-filled bushing of the present embodiment configured as described above, for example, fixes the main shaft bracket 1 to a support member on the vehicle body side and also attaches the outer cylinder bracket 2 to the wheel side mounting member, as in the first embodiment. It is used by being press-fitted into the fitting hole.
[0027]
When a vibration in the radial direction (x direction in FIG. 2) is input between the main shaft fitting 1 and the outer cylinder fitting 4, the liquid column of the low-viscosity liquid L flowing through the first orifice passage 63 in the main liquid chamber 42. the resonance effect, the vibration of the following low-frequency range 180H _Z is effectively damped. Further, the vibration of the middle and high frequency region near 250H _Z to anti-resonance occurs, it is effectively damped by the liquid column resonance of the low viscosity liquid L flowing through the second orifice passage 64 in the auxiliary liquid chamber within 43. Thereby, vibration reduction in two different frequency regions is achieved.
[0028]
As described above, according to the liquid filled bushing of the present embodiment, the first orifice passage 63 is configured such that the length distance of the first orifice passage 63 is different from the length distance of the second orifice passage 64. Since the low-viscosity liquid L flowing through the second orifice passage 64 is tuned to absorb vibration in two different frequency regions by the liquid column resonance action , the vibration is effectively absorbed in two different frequency regions. be able to. Furthermore, since the liquid-filled bush of the present embodiment has a different cross-sectional area of the first orifice passage 63 and a cross-sectional area of the second orifice passage 64, the vibration absorption efficiency in two different frequency regions is improved. Can be improved.
[0029]
When the characteristics of the liquid-filled bush of this embodiment were examined, the results shown by the solid line in FIG. 7 were obtained. 7 indicates the characteristics of the conventional liquid-filled bush shown in FIGS. 8 and 9 (the first orifice passage 153 and the second orifice passage 154 have the same length distance and cross-sectional area). As apparent from FIG. 7, fluid-filled bushing of this embodiment, vibration reduction of the 180H _Z below the low frequency range, at a mid-high frequency range different two frequency region near 250H _Z to which the anti-resonance occurs Can be seen to be compatible.
[0030]
According to the first aspect of the present invention, the first stopper portion is formed between the both axial side surfaces and the front end surface of the first stopper portion, the annular side wall portion of the rubber elastic body facing these surfaces, and the inner peripheral surface of the outer cylindrical fitting. The cross-sectional area of the first orifice passage extending in the direction crossing the radial direction, the axially opposite side surfaces and the front end surface of the second stopper portion, the annular side wall portion of the rubber elastic body facing these surfaces, and the inner periphery of the outer cylinder fitting The cross-sectional area of the second orifice passage formed in a direction crossing the radial direction between the first orifice passage and the cross-sectional area of the second orifice passage is different from each other. one for being tuned to vibration absorbing in the frequency domain, the liquid column resonance of the low-viscous liquid flowing in the first orifice passage and the second orifice passage, respectively, to absorb vibrations in two different frequency domain Door can be.
[0031]
According to invention of Claim 2, it forms between the axial side both sides and front end surface of a 1st stopper part, the annular side wall part of the rubber elastic body which opposes these surfaces, and the internal peripheral surface of an outer cylinder metal fitting. The length distance of the first orifice passage extending in the direction crossing the radial direction, the axial side surfaces and the tip surface of the second stopper portion, the annular side wall portion of the rubber elastic body facing these surfaces, and the inner cylinder fitting The length distance of the second orifice passage formed between the wall surface of the secondary liquid chamber formed between the peripheral surface and the second stopper portion and extending in the direction crossing the radial direction is set to be different from each other . Because the vibration is tuned to absorb vibration in two different frequency ranges based on the length distance of the orifice passage and the length distance of the second orifice passage, the low viscosity flows in the first orifice passage and the second orifice passage, respectively. For both liquid columns By the action, it is possible to absorb vibration with two different frequency domain.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view along the axial direction of a liquid-filled bush according to Embodiment 1 of the present invention.
FIG. 2 is a cross-sectional view taken along the direction perpendicular to the axis of the liquid-filled bush according to Embodiment 1 of the present invention.
FIG. 3 is a diagram showing characteristics of the liquid-filled bush according to Embodiment 1 of the present invention.
FIG. 4 is a cross-sectional view taken along the axial direction of a liquid-filled bush according to a modification of Embodiment 1 of the present invention.
FIG. 5 is a cross-sectional view along the axial direction of a liquid-filled bush according to Embodiment 2 of the present invention.
FIG. 6 is a cross-sectional view taken along a direction perpendicular to the axis of a liquid-filled bush according to Embodiment 2 of the present invention.
FIG. 7 is a diagram showing characteristics of a liquid-filled bush according to Embodiment 2 of the present invention.
FIG. 8 is a cross-sectional view along the axial direction of a conventional liquid-filled bush.
FIG. 9 is a cross-sectional view of a conventional liquid-filled bush along the direction perpendicular to the axis.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1,101 ... Main shaft metal fitting 2 ... Intermediate cylinder metal fitting 3, 103 ... Rubber elastic body 4, 104 ... Outer cylinder metal fitting 5, 105 ... Stopper member 21 ... Ring part 22 ... Bridging part 31, 31a, 31b ... Annular side wall part 32 ... Arm-shaped partition part 41 ... Seal rubber layer 42, 142 ... Main liquid chamber 43, 143 ... Sub liquid chamber 51, 61, 151 ... First stopper part 51a, 52a ... Buffer rubber layer 52, 62, 152 ... Second stopper part 53 53a, 63, 153 ... first orifice passages 54, 54a, 64, 154 ... second orifice passage L ... low viscosity liquid

Claims (3)

Spindle metal fittings,
An outer cylinder fitting coaxially disposed on the outer side of the spindle fitting with a space therebetween;
A rubber having a recess for forming a main liquid chamber and a sub liquid chamber on both sides in the radial direction with the main shaft metal fitting interposed therebetween, and being interposed between the main shaft metal fitting and the outer tube metal fitting. An elastic body,
A first stopper portion that is fixed to the main shaft fitting and protrudes into the main liquid chamber and a second stopper portion that protrudes into the sub liquid chamber, and has a relative displacement in the radial direction between the main shaft fitting and the outer tube fitting. A stopper member to be regulated;
In a liquid-filled bush comprising a low-viscosity liquid sealed in the main liquid chamber and the sub-liquid chamber,
In a direction crossing a radial direction formed between both side surfaces and tip surfaces of the first stopper portion in the axial direction and the annular side wall portion of the rubber elastic body facing the surfaces and the inner peripheral surface of the outer cylinder fitting. Between the cross-sectional area of the extending first orifice passage, the axially opposite side surfaces and the tip surface of the second stopper portion, and the annular side wall portion of the rubber elastic body facing these surfaces and the inner peripheral surface of the outer cylinder fitting Two cross-sectional areas of the second orifice passage extending in a direction crossing the radial direction are set different from each other, and two different frequencies are set based on the cross-sectional area of the first orifice passage and the cross-sectional area of the second orifice passage. A liquid-filled bush characterized by being tuned to absorb vibration in the region. Spindle metal fittings,
An outer cylinder fitting coaxially disposed on the outer side of the spindle fitting with a space therebetween;
A rubber having a recess for forming a main liquid chamber and a sub liquid chamber on both sides in the radial direction with the main shaft metal fitting interposed therebetween, and being interposed between the main shaft metal fitting and the outer tube metal fitting. An elastic body,
A first stopper portion that is fixed to the main shaft fitting and protrudes into the main liquid chamber and a second stopper portion that protrudes into the sub liquid chamber, and has a relative displacement in the radial direction between the main shaft fitting and the outer tube fitting. A stopper member to be regulated;
In a liquid-filled bush comprising a low-viscosity liquid sealed in the main liquid chamber and the sub-liquid chamber,
In a direction crossing a radial direction formed between both side surfaces and tip surfaces of the first stopper portion in the axial direction and the annular side wall portion of the rubber elastic body facing the surfaces and the inner peripheral surface of the outer cylinder fitting. The length distance of the extending first orifice passage, the axially opposite side surfaces and the front end surface of the second stopper portion, and the annular side wall portion of the rubber elastic body facing these surfaces and the inner peripheral surface of the outer cylinder fitting The length distance of the second orifice passage extending in the direction crossing the radial direction formed therebetween is set to be different from the length distance of the first orifice passage and the length distance of the second orifice passage. A liquid-filled bush characterized by being tuned to absorb vibration in two different frequency regions.   The liquid-filled bush according to claim 1 or 2, wherein the low-viscosity liquid has a kinematic viscosity of 100 cst or less.

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