JPH11101294A - Fluid-filled mount device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid-filled mount device through simple and compact structure, the fluid-filled mount device being formed such that a vibration control effective to input vibration of frequency areas different from each other by first and second orifice passages formed between a pressure receiving chamber and a balance chamber. SOLUTION: In this device, by partitioning a pressure receiving 46 by a hollow type auxiliary rubber elastic body 52 lower than a body rubber elastic body 16, a first pressure receiving chamber 60, a first pressure chamber 60 arranged on the outside of an auxiliary rubber elastic body 52 and a second pressure receiving chamber 62 on the inner side are partitioned independently from each other. A first orifice passage 96 is formed between the first pressure receiving chamber 60 and a balancing chamber 48, a second orifice passage 100 between the second pressure receiving chamber 62 and the balancing chamber 48. By exerting an input vibration load on both the body rubber elastic body 16 and the auxiliary rubber elastic body 52, and a pressure fluctuation is exerted directly on the first pressure receiving chamber 60 and the second pressure receiving chamber 62.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid-filled mounting device that obtains a vibration-proofing effect based on a flow action of a fluid sealed therein, and more particularly to a fluid-filled mounting device having two orifice passages.
The present invention relates to a fluid-filled mounting device in which all of the orifice passages are effectively tuned to the input vibration in the frequency range in which the orifice passage is tuned, based on the fluid flow action.

[0002]

2. Description of the Related Art As a type of a mounting device as a vibration isolating support or a vibration isolating connecting member interposed between members constituting a vibration system such as an engine mount, Japanese Patent Application Laid-Open No.
As described in JP-A-9340 and JP-A-58-29517, the first attachment member attached to one member to be vibration-isolated is attached to the other member to be vibration-isolated. The first mounting member and the second mounting member are fixed to the central portion of the main rubber elastic body which is spaced apart from the opening of the cylindrical portion in the second mounting member and closes the opening in a fluid-tight manner. The two mounting members are elastically connected by the main rubber elastic body, while the main rubber elastic body at the time of vibration input is provided on both sides of the partition member supported by the second mounting member and arranged in the cylindrical portion. A pressure receiving chamber in which a pressure change caused by elastic deformation of the pressure receiving chamber is generated, and an equilibrium chamber in which a change in volume is easily permitted by forming a part of the wall portion with a flexible film are formed. Incompressible fluid is filled in the equilibrium chamber. With, the fluid-filled mount of structure orifice passage communicating with each other equilibrium chamber with pressure receiving chamber is formed are known. In such a mounting device, an excellent vibration damping effect can be obtained based on a flow action such as a resonance action of the fluid caused to flow through the orifice passage.

By the way, the vibration damping effect based on the fluid flow action is to adjust the length of the orifice passage and the cross-sectional area of the passage while taking into consideration the wall spring rigidity of the pressure receiving chamber and the equilibrium chamber, the specific gravity and the viscosity of the sealed fluid, and the like. Therefore, it is difficult to effectively exhibit the vibration only in a relatively narrow frequency range tuned in advance. On the other hand, in the mounting apparatus, generally, a vibration isolation effect is required for a plurality of types of input vibrations having different frequency ranges. For example, in an engine mount for an automobile, a high damping effect is required for low-frequency vibration corresponding to shake or the like, and a vibration insulating effect is required for high-frequency vibration corresponding to idle vibration or the like.

Therefore, conventionally, in order to cope with such a demand, the orifice passage formed between the pressure receiving chamber and the equilibrium chamber is tuned to a low frequency range as shown in the above-mentioned publications. In addition, a liquid pressure absorbing mechanism is provided in which a movable member capable of allowing a small displacement is disposed between the pressure receiving chamber and the equilibrium chamber, and a vibration damping effect against input vibration in a high frequency range is obtained based on the displacement of the movable member. The mounting device provided, or two orifice passages tuned to different frequency ranges are formed independently of each other, and a switching valve for selectively communicating the two orifice passages is provided, whereby each There has been proposed a mounting device in which an orifice passage selectively exhibits a vibration damping effect.

However, in the former mounting device provided with the hydraulic pressure absorbing mechanism, when vibration in the tuning frequency range of the orifice passage is input, a part of the internal pressure generated in the pressure receiving chamber is absorbed by the displacement of the movable member. However, there is a problem that the vibration isolating effect of the orifice passage is likely to be reduced. On the other hand, the latter mounting device has a problem that the switching valve must be provided inside the mount and a driving means for the switching valve must be provided, so that the structure is complicated and the size is inevitably increased.

[0006]

Here, the present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide an effective vibration isolation for input vibrations in mutually different frequency ranges. An object of the present invention is to realize a fluid-filled mounting device capable of exhibiting an effect with a simple structure.

[0007]

In order to solve such a problem, a feature of the present invention is that a first attachment member attached to one member to be vibration-isolated and connected to the other member to be connected to the vibration-isolation connection. The first mounting member is attached to the central portion of the main rubber elastic body which is spaced apart from the opening of the cylindrical portion of the second mounting member attached to the member and closes the opening in a fluid-tight manner. While the mounting member and the second mounting member are elastically connected by the main rubber elastic body, on both sides of the partition member supported by the second mounting member and arranged in the cylindrical portion, There is a pressure receiving chamber in which a pressure change is caused by the elastic deformation of the main rubber elastic body at the time of vibration input, and an equilibrium chamber in which a volume change is easily allowed because a part of the wall is formed of a flexible film. Formed and uncompressed into their pressure receiving and balancing chambers With fluid is sealed,
In a fluid-filled mounting device in which an orifice passage communicating the pressure receiving chamber and the equilibrium chamber is formed, an auxiliary rubber elastic body having a hollow shape smaller than the main rubber elastic body is provided at the center of the pressure receiving chamber. A central portion of the auxiliary rubber elastic body is disposed so as to open toward the partition member, and the central portion of the auxiliary rubber elastic body is mounted at least between the two members that are vibration-isolated and subjected to a supporting load. The pressure receiving chamber is made to be displaced integrally with the center portion of the elastic body, and the pressure receiving chamber is fluid-tightly attached to the partition member with the opening portion of the auxiliary rubber elastic body. And a first pressure receiving chamber located outside the auxiliary rubber elastic body and a second pressure receiving chamber located inside the auxiliary rubber elastic body are defined, while the orifice passage serves as the orifice passage. In that the first orifice passage communicating said first pressure receiving chamber to the equilibrium chamber, the second orifice passage communicating said second pressure receiving chamber to the equilibrium chamber are formed.

In the fluid-filled mounting device having the structure according to the present invention, when vibration is input between the first mounting member and the second mounting member in the mounted state, the rubber elastic body is provided. In the body and the auxiliary rubber elastic body, each central portion is displaced substantially integrally with the first mounting member, and the outer peripheral portion or the opening is displaced substantially integrally with the second mounting member, so that It is elastically deformed. As a result, a pressure change occurs in the first pressure receiving chamber in which a part of the wall is formed of the main rubber elastic body, and in the second pressure receiving chamber in which a part of the wall is formed of the auxiliary rubber elastic body. This pressure change causes a fluid flow through the first orifice passage and the second orifice passage.

In short, in such a fluid-filled mounting device, the first pressure receiving chamber and the second pressure receiving chamber are formed independently of each other. , Internal pressure fluctuations are produced directly or independently, so that fluid flow is advantageously produced in both the first orifice passage and the second orifice passage so that each orifice passage In this case, the vibration damping effect based on the flow action of the fluid is effectively exhibited for the vibration in the frequency range in which is tuned.

[0010] Further, in such a fluid-filled mounting device, there is no need to dispose a switching valve or valve driving means for switching the orifice passage inside the mount.
There are also advantages that the structure is simple and compactness can be easily realized.

The specific shapes of the main rubber elastic body and the auxiliary rubber elastic body are not limited, and each of the first pressure receiving chamber and the second pressure receiving chamber in which a pressure change is generated at the time of vibration input is effectively used. It can be formed, and for example, a thick disk-shaped main rubber elastic body, a main rubber elastic body having an inverted cup shape, an auxiliary rubber elastic body, and the like can be adopted. A frusto-conical shape or a hollow frusto-conical shape is suitably adopted as the body, and the first mounting member is provided on the small-diameter end surface, and the cylindrical portion of the second mounting member is provided on the large-diameter end outer peripheral surface. On the other hand, while each of the auxiliary rubber elastic bodies is fixed, a truncated conical shape or a hollow truncated conical shape slightly smaller than the main rubber elastic body is preferably adopted as the auxiliary rubber elastic body. Displaced integrally with the central part Together is to be, the larger diameter side opening is attached to the fluid-tight against the partition member.
When the main rubber elastic body and the auxiliary rubber elastic body having such a truncated cone shape or a hollow truncated cone shape are employed, pressure fluctuations in the first and second pressure receiving chambers are efficiently generated at the time of vibration input, and at the same time. In addition, it is possible to reduce or prevent the occurrence of tensile stress in a mounted state where a supporting load is input, and it is possible to secure excellent load supporting performance and good durability.

Further, in the fluid-filled mounting device having the structure according to the present invention, the auxiliary rubber elastic body has its central part fixed to the central part of the main rubber elastic body in advance, and its opening part is partitioned. It is possible to adopt a structure in which the auxiliary rubber elastic body is fixed to the member in advance. The main rubber elastic body is elastically deformed by the support load applied under the mounted state of the main rubber elastic body, so that the central part of the main rubber elastic body is in contact with the central part of the auxiliary rubber elastic body. The contact state is maintained. By adopting such a structure, the input of the supporting load to the auxiliary rubber elastic body can be advantageously reduced, and in particular, in the auxiliary rubber elastic body having a small effective free length, the amount of elastic deformation is suppressed and the durability is advantageously improved. It is possible to secure.

In such a case, it is more desirable that a hard abutting member is fixedly arranged at a central portion of the auxiliary rubber elastic body with which the main rubber elastic body is abutted. Below, the central part of the main rubber elastic body can be maintained more advantageously in the state of contact with the central part of the auxiliary rubber elastic body. Also in the main rubber elastic body, it is effective to make the first mounting member face as close as possible to the surface on which the central portion of the auxiliary rubber elastic body is brought into contact, and thereby, the auxiliary rubber The displacement of the first mounting member is efficiently transmitted to the central portion of the elastic body, and the internal pressure fluctuation of the second pressure receiving chamber is caused more effectively. In particular, the first mounting member fixed to the central portion of the main rubber elastic body and the contact member fixed to the central portion of the auxiliary rubber elastic member are brought into contact with each other via a thin buffer rubber layer. Then, extremely efficient transmission of input vibration to the auxiliary rubber elastic body can be realized.

Further, the tuning for the first orifice passage and the second orifice passage is not limited at all, but preferably, the second orifice passage is higher in the high frequency band than the first orifice passage. Tuned to Thereby, while forming the first orifice passage in a form extending in the circumferential direction on the outer peripheral portion,
A second orifice passage is formed in the central portion, and the length of the first orifice passage and the cross-sectional area of the second orifice passage are increased to allow the first orifice passage and the second orifice passage to flow. It is possible to more advantageously obtain an anti-vibration effect for each input vibration in the low frequency range and the high frequency range based on the resonance action of the fluid.

Further, in the fluid-filled mounting device having the structure according to the present invention, for example, the fluid-filled mounting device is disposed in the first pressure-receiving chamber, spreads in a direction perpendicular to the vibration input direction, and has an inner periphery of the first pressure-receiving chamber. A structure in which a first umbrella member forming an annular first constricted flow path with the surface is supported by a central portion of the main rubber elastic body or the auxiliary rubber elastic body is suitably employed. By employing such a first umbrella member, based on the resonance action of the fluid circulated through the first constricted flow path, input vibration in a frequency range higher than the tuning frequency of the first orifice passage is determined. Thus, an effective vibration damping effect can be obtained.

Further, in the fluid-filled mounting device having the structure according to the present invention, for example, the fluid-filled mounting device is disposed in the second pressure receiving chamber and spreads in a direction perpendicular to the vibration input direction, so that the inner circumference of the second pressure receiving chamber is expanded. A structure is preferably employed in which a second umbrella member forming an annular second constricted flow path with the surface is supported by a central portion of the auxiliary rubber elastic body. By employing such a second umbrella member, based on the resonance action of the fluid circulated through the second constricted flow path, input vibration in a frequency range higher than the tuning frequency of the second orifice passage is determined. Thus, an effective vibration damping effect can be obtained.

Further, in the fluid-filled mounting device having the structure according to the present invention, for example, at least one of between the first pressure receiving chamber and the equilibrium chamber and between the second pressure receiving chamber and the equilibrium chamber is small. A movable member that is allowed to be displaced is provided, and the movable member is displaced based on a difference between the pressure of the first or second pressure receiving chamber and the pressure of the equilibrium chamber that is applied to both surfaces of the movable member. A hydraulic pressure absorbing mechanism that absorbs pressure fluctuations in the first or second pressure receiving chamber is preferably employed. By adopting such a hydraulic pressure absorbing mechanism, pressure fluctuation of the first or second pressure receiving chamber at the time of vibration input in a higher frequency range than the tuning frequency of the first orifice passage or the second orifice passage is absorbed, It is possible to improve the anti-vibration characteristics against high-frequency vibration by reducing it. In particular, by adopting such a hydraulic pressure absorbing mechanism in combination with the first umbrella member or the second umbrella member, a total of 4
With respect to input vibrations in two or more different frequency ranges, it is also possible to exhibit a vibration damping effect based on the resonance action of the fluid.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

First, FIGS. 1 and 2 show an engine mount 10 for an automobile as an embodiment of the present invention. The engine mount 10 has a structure in which a first mounting member 12 as a first mounting member and a second mounting member 14 as a second mounting member are connected by a main rubber elastic body 16. The first mounting bracket 12 is fixedly mounted on the power unit and the second mounting bracket 14 is fixedly mounted on the body, so that the power unit is supported on the body in a vibration-proof manner. In such a mounted state, the shared weight of the power unit is exerted between the first mounting bracket 12 and the second mounting bracket 14 in the direction of the mount axis (up and down direction in FIG. 1), so that FIG. As shown in FIG. 3, the main rubber elastic body 16 is compressed and deformed, and the first fitting 12 and the second fitting 14 are positioned close to each other by a predetermined amount. In the following description, the vertical direction is
In principle, it means the vertical direction in FIG.

More specifically, the first mounting member 12 is a cup-shaped holding member 20 having a tapered peripheral wall portion expanding toward the opening with respect to the center of the lower surface of the disk member 18.
Are fixed by welding at the opening. Further, a fixing bolt 21 protruding upward on the central axis is fixed to the disc metal fitting 18, and the first mounting metal 12 is fixed by the fixing bolt 22.
Can be attached to a power unit (not shown).

On the other hand, the second mounting member 14 is constituted by a cylindrical member 22 having a large diameter cylindrical shape and a bottom metal member 23 having a cylindrical shape having a bottom. The lower opening of the cylindrical metal fitting 22 is caulked and fixed to the flange portion 24, thereby forming a deep bottomed cylindrical shape as a whole. The cylindrical metal fitting 22 is provided with a stepped portion 26 at an intermediate portion in the axial direction. The small diameter portion 28 is located above the stepped portion 26 and the large diameter portion 30 is located below the stepped portion 26.
It has been. Further, the opening end portion on the small diameter portion 28 side is a tapered portion 32 that expands upward. Although not explicitly shown in the drawings, a bracket is fixed to the second mounting bracket 14, and the second mounting bracket 14 is attached to the vehicle body (not shown) via the bracket. Has become.

On the opening side of the second mounting member 14, the first mounting member 12 is separated on the same axis.
Are arranged to face each other. Then, the main rubber elastic body 16 is interposed between the first fitting 12 and the second fitting 14. The main rubber elastic body 16 has a truncated conical shape, and has a recess 34 that opens downward.
Is formed on the large-diameter side end surface, thereby forming a substantially hollow truncated cone. Then, the disc metal fitting 18 is superimposed on the small diameter side end face of the main body rubber elastic body 16,
The first mounting member 12 is vulcanized and bonded in a state where the holding member 20 is embedded in the axial direction from the small diameter side end surface. In addition,
The bottom wall portion 36 of the holding bracket 20 is buried to a depth that does not reach the recess 34, and a buffer rubber layer 38 is formed on the bottom wall portion 36 of the holding bracket 20. The second mounting member 14 is fixed to the large-diameter-side outer peripheral surface of the main rubber elastic body 16 by vulcanizing the inner peripheral surface of the tapered portion 32 of the cylindrical metal member 22. in short,
The main rubber elastic body 16 includes the first mounting member 12 and the cylindrical member 2.
2 is formed as an integral vulcanized molded product. The tapered peripheral wall of the holding fitting 20 in the first fitting 12 and the tapered part 32 of the tubular fitting 22 in the second fitting 14 are opposed to each other. Since the rubber elastic body 16 is interposed, compression deformation is effectively generated on the main rubber elastic body 16 when a power unit supporting load is input.

Further, inside the second mounting bracket 14,
A partition member 40 having a thick disk shape as a whole and a diaphragm 42 as a flexible film made of a thin rubber film having a substantially shallow bottomed cylindrical shape are housed and arranged. Then, the partition member 40 and the diaphragm 42 are superimposed on each other at their outer peripheral edges,
Step 26 of the cylindrical fitting 22 and flange 24 of the bottom fitting 23
Are fluid-tightly sandwiched between them, so that they are fixedly supported by the second mounting brackets 14 and arranged so as to spread in the direction perpendicular to the axis. In addition, the diaphragm 4
A ring fitting 44 is vulcanized and bonded to the outer peripheral edge of the second fitting 2 so that the holding force of the second fitting 14 is effectively exerted.

As a result, the inside of the second mounting member 14 is separated by the partition member 40 into the cylindrical member 22 and the bottom member 23.
Thus, the incompressible fluid is sealed in the cylindrical metal fitting 22 by closing the openings on both axial sides with the main rubber elastic body 16 and the partition member 40. A pressure receiving chamber 46 is defined. Further, the inside of the bottom fitting 23 is further fluid-tightly divided into an opening side and a bottom side by a diaphragm 42.
2 and a partition member 40, an equilibrium chamber 48 in which the same incompressible fluid as the pressure receiving chamber 46 is sealed is defined, while the diaphragm 42 is located on the opposite side of the diaphragm 42 from the equilibrium chamber 48. An air chamber 50 that allows deformation is defined. In addition, water, an alkylene glycol, a polyalkylene glycol, a silicone oil, or the like can be used as the sealed fluid. Particularly, in order to effectively obtain an anti-vibration effect based on a fluid resonance action, 0.1 Pa · s or less. Those having a viscosity are suitably used. Further, the fluid can be easily sealed by assembling the partition member 40 and the diaphragm 42 to the integrally vulcanized molded product of the main rubber elastic body 16 in such an incompressible fluid.

An auxiliary rubber elastic body 52 is accommodated in the pressure receiving chamber 46 and is disposed coaxially with the main rubber elastic body 16. The auxiliary rubber elastic body 52 has a concave portion 5 opened on the large-diameter side end surface, similarly to the main rubber elastic body 16.
4 and has an outer dimension slightly smaller than the main rubber elastic body 16.
Further, on the outer peripheral surface of the large-diameter side end portion of the auxiliary rubber elastic body 52, a projecting protrusion is provided upward from the peripheral edge of the central hole of the annular plate-shaped fixing bracket 56 superposed on the upper surface of the partition member 40. A tapered cylindrical portion 58 whose diameter increases upward is vulcanized and bonded. Then, the outer peripheral edge of the fixing bracket 56 and the outer peripheral edge of the partition member 40 together with the second mounting bracket 1
4 fixedly clamped by the fixing bracket 5
6 are closely overlapped on the upper surface of the partition member 40.

In other words, the auxiliary rubber elastic body 52 has its hollow interior including the recess 54 opened downward through the central hole of the fixture 56, and the central hole of the fixture 56 is fluid-tight by the partition member 40. The opening inside the hollow of the auxiliary rubber elastic body 52 is covered by being closed. Further, thereby, the pressure receiving chamber 46 is partitioned in a fluid-tight manner by the auxiliary rubber elastic body 52, so that the pressure receiving chamber 46 is located outside the auxiliary rubber elastic body 52, and a part of the wall is formed by the main rubber elastic body 16. A first pressure receiving chamber 60 is formed, and a second pressure receiving chamber 62 which is located inside the auxiliary rubber elastic body 52 and has a part of a wall formed of the auxiliary rubber elastic body 52 is formed.

A support fitting 64 is embedded and fixed at the center of the auxiliary rubber elastic body 52. The support bracket 64 has a support shaft 66 that extends downward on the central axis of the auxiliary rubber elastic body 52 and protrudes into the second pressure receiving chamber 62. An umbrella fitting 68 as a second umbrella member having a disk shape is caulked and fixed and supported. The umbrella fitting 68 has an outer diameter smaller than the inner diameter of the second pressure receiving chamber 62, and is disposed so as to spread in a direction perpendicular to the axis and divide the second pressure receiving chamber 62 into upper and lower sides. Thus, between the outer peripheral surface of the umbrella fitting 68 and the inner peripheral surface of the second pressure receiving chamber 62, a constricted passage 70 as an annular second constricted passage is formed.

Further, the auxiliary rubber elastic body 52 is formed such that its small-diameter side end surface has a height that does not reach the main rubber elastic body 16, and is disposed apart from the main rubber elastic body 16. However, when the power unit supporting load is input in the mounted state and the main rubber elastic body 16 is compressed and deformed, the central portion of the main rubber elastic body 16 is displaced downward as shown in FIG. Auxiliary rubber elastic body 5
2 is pressed against the small-diameter side end surface so that the central portion of the auxiliary rubber elastic body 52 is pushed down. As a result, the central portions of the main rubber elastic body 16 and the auxiliary rubber elastic body 52 are separated from each other by the two rubber elastic bodies 16, 52.
Are held in close contact with each other based on the elastic force of the above, and are displaced integrally. In addition, as shown in FIG. 3, in the mounted state, the first pressure receiving chamber 60 has an annular shape and surrounds the auxiliary rubber elastic body 52.

The upper surface of the support fitting 64 embedded in the central portion of the auxiliary rubber elastic body 52 is a flat surface, and a thin buffer rubber layer 74 is formed on the flat surface. Then, in the mounted state, the upper surface of the support metal member 64 is attached to the cushion rubber layers 38 and 74 with respect to the bottom wall of the holding metal member 20 fixed to the main rubber elastic body 16.
The contact state at each central portion of the main rubber elastic body 16 and the auxiliary rubber elastic body 52 is advantageously and stably maintained. Furthermore,
On the outer peripheral surface of the support bracket 64, the tapered cylindrical portion 5 of the fixing bracket 56 is embedded in a portion embedded in the auxiliary rubber elastic body 52.
8, an inverted tapered surface 72 is formed oppositely. Thereby, when the power unit supporting load is applied to the auxiliary rubber elastic body 52 by the contact of the main rubber elastic body 16, the auxiliary rubber elastic body 52 is effectively compressed and deformed.

On the other hand, the partition member 40 has a thin disk-shaped lid plate 78 overlapped and fixed to a thick disk-shaped partition plate 76 formed of a rigid material such as metal or synthetic resin. It has a structure. As shown in FIGS. 4 and 5, the partition plate 76 has an opening on the upper surface in a portion that extends over substantially half in the circumferential direction, and meanders in the circumferential direction from the central portion toward the outer peripheral side to form a zigzag shape. Has a concave groove 80 extending therethrough. In the other half portion where the concave groove 80 is not formed, a substantially rectangular accommodating recess 82 opened on the upper surface is provided.
Are formed. Furthermore, a central projection 84 protruding from the lower surface is formed integrally with a central portion of the partition plate 76, and a through hole 86 extending radially through the interior of the central projection 84 is provided. On the other hand, a central hole 88 which opens to the upper surface and extends downward is formed in the center of the partition plate 76, and the lower end of the central hole 88 is connected to the through hole 86.

When the concave groove 80 is covered with the cover plate 78, both ends are connected to the first pressure receiving chamber 60 and the equilibrium chamber 48 through the communication holes 92 and 94, and the first pressure receiving chamber 60 is connected to the first pressure receiving chamber 60. A first orifice passage 96 is formed which communicates the pressure chamber 48 with the balance chamber 48. In addition, the central hole 88 is connected to the second pressure receiving chamber 62 through a communication hole 98 provided in the cover plate 78 at one opening thereof, and through a through hole 86 at the other opening. Equilibrium chamber 4
8 so that the second pressure receiving chamber 62 and the equilibrium chamber 48 communicate with each other.
0 is formed. Further, in the housing recess 82, a flat elastic rubber plate 102 is fitted and supported in the outer peripheral portion and housed and arranged, and the opening of the housing recess 82 is covered with a cover plate 78. Such elastic rubber plate 10
The elastic deformation in the central portion of 2 is allowed by a predetermined amount. Further, communication holes 106 and 104 are formed in the bottom wall of the housing recess 82 and the cover of the housing recess 82 in the cover plate 78, respectively, and the elastic rubber plate is formed through the communication holes 104 and 106. The inner pressure of the first pressure receiving chamber 60 and the equilibrium chamber 48 is applied to the upper and lower surfaces of 102. In addition, communication holes are also provided at positions corresponding to the communication holes 92, 104 in the cover plate 78, respectively, also in the fixing bracket 56 superimposed on the cover plate 78.

In the engine mount 10 having the above-described structure, when mounted on a vehicle as shown in FIG. 3, an axial direction (between the first mounting bracket 12 and the second mounting bracket 14) is adopted. When a vibration load (up and down direction) is input, the main rubber elastic body 16 and the auxiliary rubber elastic body 52 are elastically deformed together, so that the first pressure receiving chamber 60 and the second pressure receiving chamber 62 are , A pressure fluctuation is caused, and a pressure difference is generated between the pressure chamber and the equilibrium chamber 48. As a result, a fluid flow is generated between the first pressure receiving chamber 60 and the balance chamber 48 through the first orifice passage 96, and the elastic rubber plate 102 is elastically deformed based on the elastic deformation of the elastic rubber plate 102. Fluid flow through the receiving recess 82 is generated by an amount corresponding to the elastic deformation amount. Further, a fluid flow through the second orifice passage 100 is generated between the second pressure receiving chamber 62 and the balancing chamber 48. Furthermore, in the second pressure receiving chamber 62, the umbrella fitting 68 is vibrated and displaced in the vertical direction, so that a fluid flow through the narrow passage 70 is generated.

Therefore, the first orifice passage 96 and the second orifice passage 10 where these fluid flows are generated.
In the housing recess 82 and the constricted passage 70, the length of the passage and the cross-sectional area of the passage are appropriately determined in consideration of the wall spring rigidity of the first and second pressure receiving chambers 60 and 62, the viscosity of the sealed fluid, and the like. By setting, each of these flow paths 96, 100, 82, 70
On the basis of the resonance action of the fluid flowing through
An effective anti-vibration effect can be obtained for various types of input vibration.

More specifically, for example, tuning is performed based on the resonance action of the fluid flowing through the first orifice passage 96 so that a high damping effect is exerted on input vibration in a low frequency range such as a shake. At the same time, tuning is performed based on the resonance action of the fluid flowing through the second orifice passage 100 so that a low dynamic spring effect is exerted against input vibration in a medium frequency range such as idle vibration. The spring characteristic of the elastic rubber plate 102 is tuned so that a low dynamic spring effect is exerted on input vibration in a high frequency range such as a muffled sound based on the resonance action of the fluid flowing through the narrow passage 70. It is possible to tune based on the resonance action of the fluid flowing through the pump so that a low dynamic spring effect is exerted against input vibration in a higher frequency range such as acceleration noise. Accordingly, with respect to various types of input vibrations ranging from a low frequency band to a high frequency range, it is possible to obtain a very effective vibration damping action.

The first orifice passage 96 and the housing recess 82 are always in communication with each other, but the amount of fluid flowing through the housing recess 82 is restricted by the elastic rubber plate 102. , The first orifice passage 96 has an anti-vibration effect against low-frequency, large-amplitude vibration,
And the vibration-proof effect against high-frequency small-amplitude vibrations can be effectively exhibited. Further, as is apparent from this, in the present embodiment, the accommodation pressure recess 82 and the elastic rubber plate 102 disposed therein constitute a hydraulic pressure absorbing mechanism.

Here, the engine mount 1
0, the first pressure receiving chamber 60 and the second pressure receiving chamber 62
Are separated from each other by an auxiliary rubber elastic body 52 and are formed independently of each other. When a vibration is input, internal pressure fluctuations occur independently in the first and second pressure receiving chambers 60 and 62, respectively. And the first and second pressure receiving chambers 6
0,62, the internal pressure fluctuation generated in the other pressure receiving chamber 6
It is advantageously reduced or prevented from being absorbed by the fluid flow through the orifice passages 100, 96 connected to 2, 60 and the receiving recess 82. Therefore, at the time of vibration input, the fluid flow rate can be advantageously ensured in both the first orifice passage 96 and the second orifice passage 100, and each of the orifice passages 96 and 100 is oscillated in the tuned frequency range. In contrast, the vibration-proof effect based on the resonance action of the fluid is effectively exhibited.

In the engine mount 10,
First pressure receiving chamber 6 to which first orifice passage 96 is connected
0 and a second pressure receiving chamber 62 to which the second orifice passage 100 is connected are formed independently of each other, and internal pressure fluctuations are generated independently for each of the pressure receiving chambers 60 and 62. The orifice passage 9
No orifice passage 96, 100 can be provided without providing a switching valve or valve driving means for switching between the orifices 96, 100.
The fluid flow is also effectively generated in
Therefore, a mount in which the anti-vibration effect of the two orifice passages 96 and 100 is effectively exerted against input vibrations in different frequency ranges can be advantageously realized with a simple structure and a compact size.

Further, the engine mount 1 of the present embodiment
0, when the support load of the power unit is input and the main rubber elastic body 16 is elastically deformed by a predetermined amount, the main rubber elastic body
Are brought into contact with each other to apply an external force to the auxiliary rubber elastic body 52, so that the amount of elastic deformation of the auxiliary rubber elastic body 52 is reduced, and the advantage that the durability is advantageously secured is also obtained. is there. In particular, the auxiliary rubber elastic body 52
Since the free length is smaller than that of the main rubber elastic body 16, the stress generated by the deformation due to the support load of the power unit tends to be large, but by adopting the above-described structure, the load sharing ratio with the main rubber elastic body 16 can be reduced. It can be made small and the durability can be advantageously secured.

The embodiment of the present invention has been described above in detail, but this is merely an example.
It should not be construed that the present invention is limited to the embodiment.

For example, as shown in FIG. 6, the support shaft 110 extends upward on the center axis of the auxiliary rubber elastic body 52 and projects into the first pressure receiving chamber 60 with respect to the support fitting 64.
And an umbrella fitting 1 as a first umbrella member having a disc shape with respect to the tip of the support shaft 110.
12 is fixed by caulking and the umbrella fitting 112 is fixed.
Are spread in the direction perpendicular to the axis so as to divide the inside of the first pressure receiving chamber 60 into upper and lower sides, so that the outer peripheral surface of the umbrella fitting 112 and the first pressure receiving chamber Between the inner peripheral surfaces of 60, it is also possible to form a constricted passage 114 as a first constricted flow passage having an annular shape. Such an umbrella fitting 112 is provided with the first mounting by the main rubber elastic body 16 being brought into contact with the auxiliary rubber elastic body 52 in the mounted state, as indicated by a virtual line in the figure. The input vibration from the fitting 12 is applied,
The vibration is axially displaced in the first pressure receiving chamber 60, and accordingly, the fluid flows through the constricted passage 114. Therefore, such constriction passage 114
By appropriately tuning the magnitude of the above, it is possible to obtain an effective vibration damping effect against input vibration in a predetermined frequency range based on the resonance action of the fluid caused to flow through the narrow passage 114. In addition, such an umbrella fitting 1
12 can be employed in place of the umbrella bracket 68 as the second umbrella member shown in the above-described embodiment, and can also be employed together with the umbrella bracket 68. Of course, different tunings can be performed.

The umbrella fitting 114 is provided in the first pressure receiving chamber 60.
For example, the umbrella fitting 114 is supported on the main rubber elastic body 16 side by a support shaft extending in the axial direction from the first mounting fitting 12 and protruding into the first pressure receiving chamber 60. Is also possible.

Further, in the above-described embodiment, the hydraulic pressure absorbing mechanism including the elastic rubber plate 102 is also provided between the first pressure receiving chamber 60 and the equilibrium chamber 48, but in addition to or instead of this, Such a hydraulic absorption mechanism may be provided between the second pressure receiving chamber 62 and the balancing chamber 48.

Of course, such umbrella fittings 68, 112,
The hydraulic pressure absorbing mechanisms 102 and 82 are appropriately adopted according to the vibration isolation specification required for the mount, and need not necessarily be provided. Note that, even when the umbrella member is not used, as shown in FIG.
It is desirable to embed a support fitting 116 at the center of the support rubber member, so that the auxiliary rubber elastic body 52 and the main rubber elastic body 16 can be more advantageously maintained in a contact state under the mounted state. obtain.

The first and second orifice passages 9
The specific structure, length, cross-sectional area, and the like of 6,100 are appropriately changed according to the mount structure, required characteristics, and the like, and are not limited at all.

Further, the central portion of the auxiliary rubber elastic body 52 is fixed in advance and integrally connected to the central portion of the main rubber elastic body 16 while the lower end face of the auxiliary rubber elastic body 52 on the outer peripheral side is fixed. When the power unit supporting load is input in the mounted state, the outer peripheral lower end surface of the auxiliary rubber elastic body 52 abuts on the partition member 40 when the power unit support load is input in the mounted state. It is also possible to maintain the fluid tight contact.

Further, the lower end surface on the outer peripheral side of the auxiliary rubber elastic body 52 is tightly fixed in advance to the partition member 40 as shown in the above embodiment, while the auxiliary rubber elastic body 52
May also be adopted in the center portion of the main body rubber elastic body 16 in advance. In particular, such a structure is effective when the supporting load is small or when the supporting load is not applied.

In addition, at least one of the first orifice passage 96 and the second orifice passage 100, preferably the orifice passage tuned to the high frequency side, is provided with a flow restricting means for restricting a fluid flow amount. May be. By providing such a flow restricting means to restrict the amount of fluid flow through one orifice passage, it is possible to further increase the amount of fluid flow through the other orifice passage. It is possible to further improve the vibration isolation effect based on the flow action of the fluid to be obtained. In addition, as the flow rate limiting means, for example, by disposing a movable member capable of allowing a fixed amount of displacement in the orifice passage, more specifically, for example, substantially the same as the hydraulic pressure absorbing mechanism in the above-described embodiment. Advantageously, such as by employing a structured orifice passage.

In addition, in the above-described embodiment, a specific example in which the present invention is applied to an engine mount for an automobile has been described. It is needless to say that the present invention can be similarly applied to various types of mounting devices as a support or a vibration-proof connecting body.

In addition, although not enumerated one by one, the present invention
Based on the knowledge of those skilled in the art, the present invention can be implemented in a form in which various changes, modifications, improvements, and the like are made.
It goes without saying that all such embodiments are included within the scope of the present invention, without departing from the spirit of the present invention.

[0050]

As is clear from the above description, in the fluid-filled mounting device having the structure according to the present invention, the first pressure receiving chamber and the second pressure receiving chamber are separated by the auxiliary rubber elastic body. Are formed independently of each other, and independent pressure changes occur in the first pressure receiving chamber and the second pressure receiving chamber based on the elastic deformation of the main rubber elastic body and the auxiliary rubber elastic body. In each of the first orifice passage connected to the first pressure receiving chamber and the second orifice passage connected to the second pressure receiving chamber, an effective fluid flow rate can be ensured, and each of the orifice passages An effective vibration damping effect by the fluid flow action can be exerted against the vibration of the tuning frequency.

In addition, in such a fluid-filled mount device, it is not necessary to incorporate a switching valve for the orifice passage, a valve body driving means, and the like inside the device. A mounting device capable of exhibiting an effective vibration damping effect against input vibration in a frequency range can be advantageously realized with a simple structure and a compact size.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an engine mount as one embodiment of the present invention, and is a view corresponding to a II section in FIG.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is an explanatory longitudinal sectional view corresponding to FIG. 1 and showing a state in which the engine mount shown in FIG. 1 is mounted on a vehicle.

FIG. 4 is a plan view showing a partition plate constituting the engine mount shown in FIG. 1;

FIG. 5 is a bottom view of the partition plate shown in FIG.

FIG. 6 is an explanatory longitudinal sectional view showing a main part of an engine mount as another embodiment of the present invention.

FIG. 7 is an explanatory longitudinal sectional view showing a main part of an engine mount as still another embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 10 engine mount 12 first mounting bracket 14 second mounting bracket 16 main body rubber elastic body 40 partition member 42 diaphragm 46 pressure receiving chamber 48 equilibrium chamber 52 auxiliary rubber elastic body 60 first pressure receiving chamber 62 second pressure receiving chamber 96th One orifice passage 100 Second orifice passage

Claims (7)

[Claims] 1. A first mounting member attached to one member connected in vibration isolation is spaced apart from an opening side of a cylindrical portion in a second attachment member attached to another member connected in vibration isolation. Then, the first mounting member and the second mounting member are elastically connected by the main body rubber elastic body by being fixed to the central portion of the main body rubber elastic body that closes the opening in a fluid-tight manner. On the other hand, on both sides of the partition member supported by the second mounting member and disposed in the cylindrical portion, a pressure change occurs due to the elastic deformation of the main rubber elastic body at the time of vibration input. The chamber and a part of the wall are formed of a flexible membrane to form an equilibrium chamber in which a volume change is easily allowed, and the incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber. With the pressure chamber and the equilibrium chamber communicating with each other. In the fluid-filled mounting device in which the orifice passage is formed, a hollow auxiliary rubber elastic body smaller than the main rubber elastic body is disposed so as to open toward the partition member at the center inside the pressure receiving chamber. The center portion of the auxiliary rubber elastic body is displaced integrally with the center portion of the main rubber elastic body under a state where the supporting rubber elastic body is attached to at least the two members connected to each other and subjected to a supporting load. The pressure receiving chamber is partitioned by the auxiliary rubber elastic body, and the opening portion of the auxiliary rubber elastic body is fluid-tightly attached to the partition member. A first pressure receiving chamber located on the outside and a second pressure receiving chamber located on the inside are defined, while the first pressure receiving chamber communicates with the equilibrium chamber as the orifice passage. A fluid-filled mounting device, wherein a first orifice passage and a second orifice passage connecting the second pressure receiving chamber to the equilibrium chamber are formed. 2. The auxiliary rubber elastic body is fixed to the partition member in an opening portion thereof in a fluid-tight manner, and is disposed apart from the main rubber elastic body.
The main rubber elastic body is elastically deformed by the supporting load, so that a central portion of the main rubber elastic body is maintained in contact with the central portion of the auxiliary rubber elastic body. 2. The fluid-filled mounting device according to 1. 3. The fluid-filled mounting device according to claim 2, wherein a hard contact member is fixedly arranged at a central portion of the auxiliary rubber elastic body with which the main rubber elastic body is brought into contact. 4. The fluid-filled mounting device according to claim 1, wherein the second orifice passage is tuned to a higher frequency band than the first orifice passage. 5. An annular first constricted flow path disposed in the first pressure receiving chamber and extending in a direction perpendicular to a vibration input direction and formed between the first pressure receiving chamber and an inner peripheral surface of the first pressure receiving chamber. The fluid-filled mounting device according to any one of claims 1 to 4, wherein the first umbrella member is supported by a center portion of the main rubber elastic body or the auxiliary rubber elastic body. 6. An annular second constricted flow path disposed in the second pressure receiving chamber and extending in a direction perpendicular to the vibration input direction and between the second pressure receiving chamber and an inner peripheral surface of the second pressure receiving chamber. The fluid-filled mounting device according to claim 1, wherein the second umbrella member is supported by a central portion of the auxiliary rubber elastic body. 7. A movable member capable of allowing a small displacement is provided between at least one of the first pressure receiving chamber and the balancing chamber and between at least one of the second pressure receiving chamber and the balancing chamber. The movable member is displaced based on the difference between the pressure of the first or second pressure receiving chamber applied to both surfaces of the movable member and the pressure of the equilibrium chamber, whereby the first or second pressure receiving chamber is displaced. 7. The fluid-filled mounting device according to claim 1, further comprising a hydraulic pressure absorbing mechanism that absorbs pressure fluctuations.