JP2000337426A - Fluid sealing type cylindrical mount - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid sealing type cylindrical mount to set vibration control characteristics different in two axial orthogonal directions orthogonally to each other and further improve vibration control characteristics based on the fluid action of fluid provided in one axial orthogonal direction, and provide a vibration control effect effective to input vibration in a prizing direction and an axial direction, and, for example, favorably applicable for a strut mount for an automobile. SOLUTION: In the side wall part 48 in an axial direction of each of four division fluid chambers formed between a shaft member 12 and an outer cylinder member 14, a peripherally extending elastic protrusion 42 is formed at an outer peripheral part where axial projection is not applied on a shaft member 12. The protrusion tip face of the elastic protrusion 42 is brought into contact with a member 22 (20) on the side where the outer cylindrical member 14 is mounted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid-filled cylindrical mount having an anti-vibration effect based on the flow action of a fluid enclosed therein, and more particularly to a fluid-filled cylindrical mount in two perpendicular directions perpendicular to each other. And the vibration isolation characteristics of the
The present invention relates to a fluid-filled cylindrical mount that can exert an effective vibration damping effect against input vibration in a twisting direction and can be advantageously applied to, for example, a strut mount for an automobile.

[0002]

2. Description of the Related Art A shaft member and an outer cylindrical member arranged radially outwardly separated from each other are connected by a rubber elastic body interposed between their radially opposed surfaces, so that the shaft member and the outer member are connected to each other. As a kind of cylindrical mount that has a vibration-proof effect against vibration input between the cylindrical members, a part of the wall is rubber elastic between the shaft member and the radially opposed surface of the outer cylindrical member. A fluid-filled cylindrical mount that is formed of a body and forms a fluid chamber in which an incompressible fluid is sealed, and uses a vibration-proof effect exerted based on a flow action such as a resonance action of the sealed fluid. For example, application to strut mounts, engine mounts, body mounts, suspension mounts, and the like for automobiles is being studied.

In such a fluid-filled cylindrical mount, when different vibration isolation characteristics are required in two orthogonal directions perpendicular to each other, for example, Japanese Patent Laid-Open No. As described in JP-A-63084, etc., a fluid chamber which extends in the circumferential direction between a shaft member and an outer cylindrical member and has walls on both axial sides formed of a rubber elastic body is formed. A pair of first elastic partition walls extending radially from the shaft member toward the outer cylinder member on both sides,
Partitioned by a pair of second elastic partition walls extending radially on both sides perpendicular to the pair of first elastic partition walls from the shaft member toward the outer cylindrical member, each of which is filled with an incompressible fluid. A structure in which four divided fluid chambers are formed, and a pair of first orifice passages respectively connecting two divided fluid chambers positioned on both sides of the pair of first elastic partition walls are provided. Etc. have been proposed. In the cylindrical mount having such a structure, the spring characteristics of the first elastic partition wall and the second elastic partition wall are relatively adjusted, the first orifice passage is appropriately tuned, and the like. Thus, different vibration isolation characteristics can be advantageously set in the two directions perpendicular to the axis.

[0004] In recent years, in such a fluid-filled cylindrical mount, further improvement in the vibration-proofing effect has been demanded, and even in a twisting direction inclined in the axial direction. In some cases, improvement in vibration isolation performance is required. For example, in a strut mount in which an upper end portion of a piston rod of a shock absorber is supported on a body side in a vibration-isolating manner in a vehicle, different spring constants are required in a vehicle transverse direction and a front-rear direction, which are different from each other in a direction perpendicular to an axis. Also, anti-vibration characteristics in a twisting direction on a plane extending in the lateral direction are required.

[0005] In order to achieve such required characteristics even in the cylindrical mount having the conventional structure as described above,
Further improvement was desired.

[0006]

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide an anti-vibration effect based on the flow action of a sealed incompressible fluid. It is an object of the present invention to provide a fluid-filled cylindrical mount having a novel structure, which can exert more effectively and also exerts an effective anti-vibration effect against input vibration in a twisting direction.

[0007]

An embodiment of the present invention which has been made to solve such a problem will be described below. In addition, each aspect described below can be adopted in any combination. Further, aspects and technical features of the present invention are described in the entire specification and the drawings without being limited to those described below.
Alternatively, it should be understood that the present invention is recognized based on the inventive concept that can be grasped by those skilled in the art from the description thereof.

First, a first aspect of the present invention is an outer cylinder attached to the other member to be vibration-isolated and connected to a shaft member attached to one of the members to be vibration-isolated and separated radially outward. The shaft member and the outer cylinder member are connected by a rubber elastic body, and the walls on both sides in the axial direction are formed of the rubber elastic body. And a pair of first elastic partition walls extending radially on both sides from the shaft member toward the outer cylinder member, and a pair of first elastic partition walls extending from the shaft member toward the outer cylinder member. And divided by a pair of second elastic partition walls extending radially on both sides perpendicular to the pair of first elastic partition walls to form four divided fluid chambers each containing an incompressible fluid. With the pair of first elastic partition walls. In the fluid-filled cylindrical mount provided with a pair of first orifice passages that respectively communicate the two divided fluid chambers with each other, the axially outer wall of each of the divided fluid chambers has an axially outer wall. Elastic projections extending in the circumferential direction and projecting toward the outer peripheral side from the shaft member in the axial projection so as not to cover the pair of second elastic partition walls. In a state where the elastic projections are mounted between the members to be vibrated, the protruding distal end surfaces of the respective elastic projections are configured to abut against members on the side to which the outer cylindrical member is attached.

In the fluid-filled cylindrical mount having the structure according to this aspect, the elastic projections protruding from the side walls in the axial direction of each of the divided fluid chambers have members on the side to which the outer cylinder member is attached. , The wall spring stiffness at both axial side walls of the divided fluid chamber is improved. As a result, the pressure change in each of the divided fluid chambers is more positively generated at the time of vibration input in the direction perpendicular to the axis, and particularly, at the time of vibration input in the radial direction in which the pair of second elastic partition walls extend, the first As a result, the amount of fluid flowing through the orifice passage is increased, so that the vibration damping effect based on the fluid action such as the resonance action of the fluid can be more effectively exerted.

Further, in such a fluid-filled cylindrical mount, the elastic projections projecting from both axial side walls of the divided fluid chamber are positioned so as to be displaced to the outer peripheral side from the shaft member when projected in the axial direction. Therefore, the rigidity of the axial spring of the mount due to the provision of the elastic projection is avoided, and the vibration isolation performance in the axial direction can be advantageously secured.

Further, in such a fluid-filled cylindrical mount, elastic projections projecting from both axial side walls of the divided fluid chamber are positioned so as to be displaced to the outer peripheral side from the shaft member when projected in the axial direction. Therefore, even when the shaft member is displaced relative to the outer cylinder member in the direction perpendicular to the axis due to the input of a load or vibration in the direction perpendicular to the axis, the relative displacement of the elastic projection with respect to the outer cylinder member is suppressed. In addition, rubbing or the like of the contact surface with the member on the side to which the outer cylinder member is attached is reduced, so that durability can be advantageously secured.

Further, in such a fluid-filled cylindrical mount, the elastic projections projecting from the axially opposite side walls of the divided fluid chamber are positioned so as to be displaced to the outer peripheral side from the shaft member when projected in the axial direction. In addition, since it is formed so as to be divided in the circumferential direction so as not to cover the second elastic partition wall, in the prying direction on the radial plane where the second elastic partition wall extends, the high spring due to the elastic projections Has been avoided,
A good anti-vibration effect can be exhibited in such a twisting direction.

According to a second aspect of the present invention, there is provided a fluid-filled cylindrical mount having a structure according to the first aspect, wherein the pair of first elastic partition walls is replaced with the second elastic partition wall. It is characterized in that it has a small thickness dimension in the circumferential direction. In such an embodiment, the spring characteristic of the first elastic partition wall is set to be softer than that of the second elastic partition wall, so that the pair of first elastic partition walls extend in the radial direction and the pair of second elastic partition walls extend in the radial direction. The spring ratio with respect to the radial direction in which the elastic partition wall extends can be set larger.

According to a third aspect of the present invention, there is provided a fluid-filled cylindrical mount having a structure according to the first or second aspect, wherein at least one axial end of the shaft member has an outer peripheral surface. An upwardly projecting flange-like part is integrally formed, and the flange-like part is fixed to an axial wall of the fluid chamber formed of the rubber elastic body, and the elastic projection is formed by axial projection. It is characterized in that it is formed at a position off the outer peripheral side from the flange-shaped portion. According to such an embodiment, the axial wall of the fluid chamber, and thus the wall spring stiffness of the fluid chamber, can be set to be greater by the rigid flange-like portion. The effect of improving the vibration isolation performance based on the above can be more advantageously achieved. Moreover, by forming the elastic projection at a position off the flange-shaped portion in the axial projection, remarkably high springs in the mount axial direction can be advantageously avoided, and the axial vibration isolation performance can be sufficiently improved. Can be secured. The flange portion may be formed at one axial end of the shaft member and fixed to only one axial wall portion of the fluid chamber, but may be formed at both axial end portions of the shaft member. Alternatively, the fluid chambers may be fixed to the walls on both sides in the axial direction.

According to a fourth aspect of the present invention, there is provided a fluid-filled cylindrical mount having a structure according to any one of the first to third aspects, wherein the pair of first elastic partition walls and the pair of first elastic partition walls are provided. Characterized in that at least one of the second elastic partition walls is provided with a hard restraining projection projecting radially from at least one side of the shaft member and the outer cylinder member toward the other side. I do. In such an embodiment, the spring rigidity of the elastic partition wall can be adjusted by the restraining protrusion. For example, by appropriately adjusting the size of the restraining protrusion, in the directions perpendicular to the axes perpendicular to each other. Can be set with a greater degree of freedom in tuning, and by increasing the wall spring stiffness of the first elastic partition wall with the constraining projection, the pair of second elastic partition walls extends in the radial direction. At the time of vibration input, a larger pressure difference is generated between the two divided fluid chambers located on both sides of the first elastic partition wall to increase the amount of fluid flowing through the first orifice passage. It is also possible to further improve the vibration isolation effect based on the flow action such as the resonance action.

According to a fifth aspect of the present invention, there is provided a fluid-filled cylindrical mount having a structure according to any one of the first to fourth aspects, wherein each of the elastic projections is provided with the first elastic partition. Straddling the wall, forming a pair so as to be continuous in the circumferential direction between the walls of the two divided fluid chambers positioned on both sides in the circumferential direction with the first elastic partition wall interposed therebetween, Features. In this embodiment, the elastic projection is formed so as not to be connected to the second elastic partition wall but to be directly connected to only the first elastic partition wall. An elastic projection that can effectively increase the rigidity of the wall spring of each divided fluid chamber while avoiding an increase in rigidity can be realized.

According to a sixth aspect of the present invention, in a fluid-filled cylindrical mount having a structure according to any one of the first to fifth aspects, the fluid-filled cylindrical mount is attached to the other member to be vibration-isolated. Using a tubular bracket, the outer tubular member is fixedly fitted inside the tubular portion of the bracket, and an annular contact protruding portion extending radially inward from both axial openings is formed integrally with the bracket. Thus, the protruding distal end surface of the elastic projection is brought into contact with the corresponding contact projection. According to this aspect, the contact surface on which the elastic protrusion comes into contact can be advantageously formed by using the bracket, whereby the elastic protrusion is stably and surely brought into contact. This makes it possible to obtain the desired anti-vibration characteristics with high reliability.

According to a seventh aspect of the present invention, there is provided a fluid-filled cylindrical mount having a structure according to any one of the first to sixth aspects, wherein one of the pair of first orifice passages is provided. It is characterized in that tuning is performed such that a low dynamic spring effect based on the resonance action of the fluid is exerted in a frequency range in which the anti-resonance action of the fluid caused to flow through the other orifice passage is generated. According to this aspect, different tuning is performed on the pair of first orifice passages, and the fluid that is caused to flow through the first orifice passage tuned to the low frequency range is adjusted. Due to the anti-resonance effect, a remarkably high dynamic spring in the direction perpendicular to the axis in a specific frequency range and a remarkable decrease in vibration isolation performance caused the second orifice passage tuned to the high frequency range to flow. By reducing or eliminating the resonance effect of the fluid, a favorable vibration isolation effect can be advantageously achieved over a wide frequency range.

According to an eighth aspect of the present invention, there is provided a fluid-filled cylindrical mount having a structure according to any one of the first to seventh aspects, with the pair of second elastic partition walls interposed therebetween. It is characterized in that a pair of second orifice passages are provided to mutually communicate the two divided fluid chambers located on both sides, respectively. In this embodiment,
Even when vibration is input in the radial direction in which the pair of first elastic partition walls extend, an anti-vibration effect based on a flow action such as a resonance action of a fluid caused to flow through the second orifice passage is exhibited. Become. Therefore, for any of the vibrations input in the two orthogonal directions perpendicular to each other, it is possible to obtain excellent vibration isolation performance by utilizing the vibration isolation effect based on the fluid flow action. . In this case, it is desirable that the first orifice passage and the second orifice passage be tuned differently in consideration of vibrations input in each direction.

According to a ninth aspect of the present invention, there is provided a fluid-filled cylindrical mount having a structure according to any one of the first to eighth aspects, wherein the shaft member is provided with a shock absorber for an automobile. While fixing the piston rod,
A cylindrical bracket is externally fitted and fixed to the outer cylindrical member, and the outer cylindrical member is fixed to the body side of the vehicle via the bracket, so that the axial directions of the shaft member and the outer cylindrical member are different from those of the vehicle. And the pair of first elastic partition walls and the pair of second elastic partition walls are mounted on the vehicle in a state where the pair of first elastic partition walls and the pair of second elastic partition walls extend in the front-rear direction and the left-right direction of the vehicle. An annular contact protrusion, which is integrally formed by expanding inward in the radial direction from the opening on both sides in the direction, is brought into contact with the protrusion end surface of the elastic protrusion,
An axially upper end of the shaft member is integrally formed with a flange-like portion protruding on the outer peripheral surface, and is fixed to an axial wall portion of the fluid chamber formed of the rubber elastic body. The flange-shaped portion is axially separated from and opposed to the contact protrusion formed integrally with the upper opening in the axial direction of the bracket, and in the projection in the axial direction, the elastic projection is moved away from the flange-shaped portion. It is characterized in that it is provided at a position off the outer peripheral side.

In the fluid filled type vibration damping device having such a structure according to the present embodiment, a strut mount for an automobile is advantageously realized, and in particular, the left and right sides of the vehicle which greatly affect the maneuverability of the vehicle. In the direction, an effective vibration damping effect based on the flow action of the fluid that is caused to flow through the first orifice passage is exhibited, and in the vehicle vertical direction in which a shock load, which is a problem, is input, the shaft member When the flange-shaped portion is brought into contact with the contact protrusion of the bracket, a large load-bearing performance can be realized. In addition, in the vehicle left-right direction where the load is easy to be input, the elastic projections are divided on the second elastic partition walls located on both sides in the vehicle left-right direction. A vibration effect can be exhibited.

In particular, in the ninth aspect, the second aspect can be advantageously employed in combination, whereby the input load in the vehicle longitudinal direction between the shaft member and the outer cylinder member is compressed / tensile. The spring stiffness of the first elastic partition wall exerted in the direction is set sufficiently lower than the spring stiffness of the second elastic partition wall exerted in the compression / tension direction by the input load in the lateral direction of the vehicle. As a result, good ride comfort based on low spring stiffness in the vehicle front-rear direction and good steering stability based on high spring stiffness in the vehicle left-right direction can be achieved at the same time at a higher level.

[0023]

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 to 4 show an automotive strut mount 10 according to a first embodiment of the present invention. The strut mount 10 includes an inner cylinder fitting 12 as a shaft member and an outer cylinder fitting 14 as an outer cylinder member arranged radially outwardly apart from the rubber elastic body 16.
Has a structure elastically connected by the As shown in FIG. 5, the upper end of the piston rod 18 of the shock absorber is inserted and fixed to the inner cylinder 12, while the outer cylinder 14 is connected to the body of the automobile via the bracket 20. By attaching to the body 22, the piston rod 18 of the shock absorber is connected to the body 22 in a vibration-proof manner.

More specifically, the inner cylindrical fitting 12 has a straight, small-diameter, thick-walled cylindrical shape, and has one end in the axial direction (the upper end in FIG. 2) having a radially outer portion. An annular plate-shaped flange portion 24 is formed integrally with the annular portion. In addition, a constraint block 2
6 is fixed.

The constraining block 26 is formed of a hard material such as a synthetic resin material, and is fixed to the inner cylinder fitting 12 so as to cover substantially the entire outer peripheral surface of the inner cylinder fitting 12. Further, a pair of first restraining protrusions projecting outward in the radial direction are provided at portions opposed to each other with the inner cylinder fitting 12 sandwiched in one radial direction (vertical direction in FIG. 1). The portions 28, 28 are integrally formed, and the inner cylindrical fitting 12 is formed in a radial direction (left-right direction in FIG. 2) perpendicular to the portions.
A pair of second restraining protrusions 30, 30 protruding outward in the radial direction are integrally formed at portions opposed to each other with the body therebetween. Each of the first restraining protrusion 28 and the second restraining protrusion 30 is formed over the entire length of the restraining block 26 in the axial direction. The second constraining protrusions 30 have substantially the same radial protruding height, and the circumferential width of the second constraining protrusions 30 is larger than that of the first constraining protrusions 28. .
At substantially the center of the first constraining projections 28, 28, a through-hole 32 that extends linearly in a direction substantially perpendicular to the projecting direction and substantially in the circumferential direction of the mount is formed in a substantially constant circular shape over the entire length. They are formed one by one with a cross-sectional shape.

An annular projection 34 is formed integrally with the restraining block 26 on the axially outer surface of the flange 24 of the inner cylinder fitting 12, and the annular projection 34 is formed outside the flange 24. It is formed on the entire periphery in the circumferential direction at the peripheral portion, and protrudes outward in the axial direction.

Further, an intermediate sleeve 36 is provided on the outer peripheral side of the inner cylinder fitting 12, and is positioned so as to surround the outer peripheral surface of the inner cylinder fitting 12 radially outward. . The intermediate sleeve 36 is formed of a hard material such as a metal and has a large-diameter cylindrical shape.
And are arranged substantially coaxially. Also, the intermediate sleeve 36
Are provided with four windows 38a to 38d, which are formed in the axially intermediate portion of the intermediate sleeve 36 so as to be circumferentially separated from each other.

A rubber elastic body 16 is disposed between the radially opposed surfaces of the inner cylindrical fitting 12 and the intermediate sleeve 36. The inner cylindrical fitting 12 is vulcanized and adhered to the inner peripheral surface of the rubber elastic body 16. At the same time, the intermediate sleeve 36 is vulcanized and adhered to the outer peripheral surface of the rubber elastic body 16 so that
And the intermediate sleeve 36 are elastically connected by the rubber elastic body 16. In particular, in the present embodiment, the rubber elastic body 1
6 is formed as an integrally vulcanized molded product including the inner cylinder fitting 12 and the intermediate sleeve 36.

Further, in such an integrally vulcanized molded product, each of the pair of first restraining projections 28, 2 protruding from the inner cylinder fitting 12 side.
8 and the inner cylindrical fitting 12 such that the protruding distal end surfaces of the second restraining projections 30 and 30 are opposed to portions of the intermediate sleeve 36 where the window 38 is not formed.
And the relative position of the intermediate sleeve 36 in the circumferential direction are set. In the rubber elastic body 16, four pocket-shaped recesses 40 a to 40 d which are respectively opened on the outer peripheral surface are formed in the axially intermediate portion. Each of these pocket-shaped recesses 40a to 40d is formed between the first constraint protrusion 28 and the second constraint protrusion 30 that are adjacent in the circumferential direction,
Each of the window portions 38a-38 provided in the intermediate sleeve 36
Through d, it is opened to the outer peripheral surface of the intermediate sleeve 36.

In short, each of the pocket-shaped recesses 40 has both side walls 48, 48 on both sides in the axial direction.
6. Further, between the pocket-shaped recesses 40 adjacent to each other in the circumferential direction, each is formed of a rubber elastic body 16, and extends radially across the space between the inner cylinder fitting 12 and the intermediate sleeve 36. Partition wall 44,
46 are provided inside the elastic partition walls 44 and 46,
30 is fixed in an embedded state. In particular, as shown in FIG. 1, among the four elastic partition walls, the first elastic partition walls 44, 44 on which the first restraining projections 28, 28 are embedded and fixed, are the second restraining projections. The circumferential thickness is smaller (T1 <T2) than the second elastic partition walls 46, 46 on which the protruding portions 30, 30 are embedded and fixed, and the second elastic partition wall 4 is formed.
6 has a higher spring rigidity than the first elastic partition wall 44.

Further, as shown in FIGS. 2 to 4, the rubber elastic body 16 is formed integrally with a pair of elastic projections 42, 42 protruding axially outward from both axial end surfaces. The intermediate sleeve 36 projects axially outward from both axial end surfaces of the intermediate sleeve 36. This elastic projection 4
2, 42 have a predetermined length in the circumferential direction (approximately 1 /
(Length of 4 circumferences), and is formed with a constant substantially mountain-shaped cross-sectional shape over the entire length, and is opposed to the inner cylindrical fitting 12 in the radial direction in which the first restraining projections 28 project. ing. In particular, these elastic projections 42, 42 are provided in the inner cylinder fitting 12 in the radial direction in which the first elastic partition walls 44, 44 extend.
And a circumferential length that does not reach the axial end face of the second elastic partition wall 46 from the axial end face of the first elastic partition wall 44 toward both sides in the circumferential direction. Thus, it is formed on the side wall portion 48 of each pocket-shaped recess 40. That is, each elastic projection 42 straddles the first elastic partition wall 44 and is located at each of two pocket-shaped recesses (40a, 40b, 40c) positioned on both circumferential sides of the first elastic partition wall 44. And 40d) are formed so as to be continuous in the circumferential direction between the axial wall portions. The elastic projection 42 may be formed on the outer peripheral edge of the rubber elastic body 16, but in the present embodiment,
It is formed to extend in the circumferential direction at a radially intermediate portion slightly radially inward from the outer peripheral edge.

The elastic projections 42, 42 provided on the side wall 48 on the side (the upper side in FIGS. 3 to 5) on which the flange 24 of the inner cylindrical metal fitting 12 is embedded and fixed are formed by projections in the axial direction. It is located radially outward of the flange 24 of the tubular fitting 12 and is formed so as not to overlap the flange 24 in the axial direction. In particular, in the present embodiment,
In the projection in the axial direction, the elastic projection 42 provided on the first elastic partition wall 44 is positioned radially outward of the first restraining projection 28. Thereby, the inner cylinder fitting 1
2 is also displaced in the radial direction relative to the outer cylinder 14, the displacement of the elastic projection 42 integrally with the inner cylinder 12 is avoided, and the diameter of the elastic projection 42 relative to the outer cylinder 14 is reduced. The relative displacement amount in the direction is reduced as compared with the relative displacement amount in the radial direction of the inner cylinder fitting 12 with respect to the outer cylinder fitting 14.

Further, an outer tube fitting 14 is externally attached to such an integrally vulcanized molded product. The outer cylindrical member 14 has a large-diameter cylindrical shape slightly larger than the intermediate sleeve 36, and a thin seal rubber layer 50 is vulcanized and bonded to the inner peripheral surface over substantially the entire surface. . The outer tube fitting 14 is fixed in a fluid-tight manner to the outer peripheral surface of the intermediate sleeve 36 by being reduced in diameter by an eight-way drawing process or the like, and both ends in the axial direction are rolled and caulked. , Are locked and fixed to both axial end surfaces of the intermediate sleeve 36. The elastic projections 42, 42 protruding from both axial end surfaces of the rubber elastic body 16 are provided.
Is projected further outward than the axial end face of the outer sleeve 14 locked to the axial end face of the intermediate sleeve 36.

Thus, the openings of the pocket-shaped recesses 40a to 40d formed in the integrally vulcanized molded product are covered with the outer tube fitting 14 in a fluid-tight manner, and an incompressible fluid is sealed therein. Thus, a total of four divided fluid chambers 52a to 52d are formed. That is, these divided fluid chambers 52a to 52d
In other words, one annular fluid chamber extending in the circumferential direction between the radially opposed surfaces of the inner cylindrical fitting 12 and the outer cylindrical fitting 14 includes a pair of first elastic partition walls 44, 44 and a second elastic partition. Wall 4
By being partitioned by 6, 46, they are formed so as to be separated from each other in the circumferential direction.

The divided fluid chambers 52a to 52d can be filled with an incompressible fluid by, for example, fitting the outer tube 14 to the integrally vulcanized molded product in the incompressible fluid. Divided fluid chamber 52a by assembling outer cylinder fitting 14
To d can be formed at the same time. Water, alkylene glycol, polyalkylene glycol, silicone oil, or the like can be used as the sealed fluid. Particularly, in order to effectively obtain a vibration damping effect based on the resonance action of the fluid described below, the viscosity is 0.1 Pa. -A low-viscosity fluid of s or less is suitably used.

In the strut mount 10 having such a structure, each of the pair of divided fluid chambers 5 located on both sides in the circumferential direction with the first elastic partition walls 44, 44 therebetween.
2a and 52b and 52c and 52d are connected to each other through the through hole 32 of the first restraining projection 28, and the through holes 32 and 32 allow the pair of divided fluid chambers 52a and 52b to communicate with each other. And a pair of first orifice passages 54, 54 are formed to allow fluid flow between 52c and 52d. On the other hand, a pair of divided fluid chambers 52a and 52c and 52b and 52 located on both sides in the circumferential direction with the second elastic partition walls 46 and 46 interposed therebetween.
d are completely independent of each other, so that a pair of divided fluid chambers 52a and 52b positioned on both sides of one first elastic partition wall 44 are connected to the other first elastic partition wall. It is formed completely independently of another pair of divided fluid chambers 52c and 52d located on both sides of the 44.

Then, the strut mount 10
As shown in FIG. 5, the upper end of the piston rod 18 of the shock absorber is inserted into the inner cylinder 12 and bolted thereto, while the bracket 20 is attached to the outer cylinder 14. It is externally fitted and fixed, and the outer tube fitting 14 is connected to the vehicle body 2 via the bracket fitting 20.
2, the piston rod 18 is elastically connected to the body 22.

Here, the bracket 20 is composed of an upper cylinder 56 and a lower cylinder 58. Each of the upper and lower cylindrical fittings 56 and 58 has a large-diameter cylindrical shape, and has a mounting plate portion 60 that extends radially outward at one end in the axial direction. At the other end in the axial direction, an annular plate-shaped contact protrusion 62 expanding radially inward is integrally formed. The upper and lower cylindrical fittings 56 and 58 are externally inserted into the outer cylindrical fitting 14 from both sides in the axial direction of the strut mount 10 with the respective mounting plate portions 60 facing forward. The plate portions 60 are fixed to the strut mount 10 in a state where they are overlapped with each other. The upper and lower cylindrical fittings 56 and 58 may both be press-fitted and fixed to the outer cylindrical fitting 14. However, in the present embodiment, only the upper cylindrical fitting 56 is attached to the outer cylindrical fitting 56 in consideration of the workability of assembly. Hardware 14
Is press-fitted and fixed.

That is, in this assembled state, the bracket 20 is externally fitted and fixed to the outer tube 14 of the strut mount 10 at its cylindrical portion, and the mounting plate portions 60, 60 are overlapped with each other. Then, it protrudes radially outward from the axially intermediate portion of the outer tube fitting 14, and furthermore, the abutting projections 62, 62 are provided at the axially opposite ends of the strut mount 10 at the axis of the outer tube fitting 14. The rubber elastic body 16 extends outward in the radial direction so as to cover the end face in the direction, and is positioned so as to cover the rubber elastic body 16 at a distance outside in the axial direction. Then, the mounting plate portion 6 which is superposed
The bracket fitting 20 is bolted to the body 22 in a bolt hole 64 formed by superimposing the body 0 and 60 on the body 22 and penetrating through the mounting plate parts 60 and 60.

Further, the contact protrusion 62 is formed by the rubber elastic body 16.
The projections of the elastic projections 42 abut on the axially inner surfaces of the abutting projections 62 so as to extend radially inward from the positions where the elastic projections 42 are formed. Have been.

In the projection in the axial direction, the abutting projection 62 does not overlap with the main body of the inner cylinder fitting 12, but does not overlap with the outer peripheral edge of the flange portion 24 projecting from the inner cylinder fitting 12. It has a radially protruding dimension enough to overlap. In other words, the inner diameter of the contact projection 62 is set to be larger than the outer diameter of the main body of the inner cylindrical fitting 12 and smaller than the outer diameter of the flange 24. Thereby, the annular protrusion 34 protruding from the outer peripheral edge of the flange portion 24 is
The contact protrusion 62 is spaced apart from the contact protrusion 62 in the axial direction and is opposed to the contact protrusion 62. In addition, on the protruding tip surface of the annular protrusion 34,
The rubber elastic body 16 forms a buffer rubber layer.

When the strut mount 10 is mounted on the vehicle as described above, the center axes of the inner and outer cylindrical fittings 12 and 14 are substantially in the vertical direction of the vehicle (substantially in the vertical direction) as shown in FIGS. ), The flange portion 24 of the inner cylinder fitting 12 is positioned on the upper side, and the inner cylinder fitting 1 is
The first elastic partition walls 44, 44 extend in the front-rear direction of the vehicle and the second elastic partition walls 46, 46 extend in the left-right direction of the vehicle.

In such a strut mount 10, the first elastic partition walls 44, which are subjected to compression / tensile deformation with respect to input vibration in the vehicle longitudinal direction, have low dynamic spring characteristics. In addition, excellent vibration insulation based on soft spring characteristics, that is, an anti-vibration effect is exhibited, so that good vehicle riding comfort is realized. The second elastic partition wall 4 having a large spring rigidity
6 and 46 are mainly subjected to shear deformation, so that the second elastic partition walls 46 and 46 do not significantly impair the vibration isolation characteristics.

On the other hand, the second elastic partition wall 4 that is compressed / tensilely deformed against an input load in the vehicle left-right direction.
6, 46 have a high spring stiffness, so that a large roll displacement or the like is suppressed, and excellent steering stability is realized. In addition, when vibration is input in the lateral direction of the vehicle, the relative displacement of the inner and outer cylindrical fittings 12 and 14 causes the fluid between the divided fluid chambers 52a and 52b on both sides of the first elastic partition wall 44 and between them. A relative pressure difference is created between 52c and 52d, respectively.
Since the fluid flow is generated through the first orifice passage 54 based on the pressure difference, an effective vibration damping effect is exhibited based on the resonance action of the fluid flowing through the first orifice passage 54. You get. By appropriately adjusting the ratio between the passage length of the first orifice passage 54 and the passage cross-sectional area according to the vibration frequency to be damped, etc., a more effective vibration damping effect can be obtained for the vibration to be damped. Can be obtained.

In the strut mount 10 as described above, the rigidity of the side walls 48 on both axial sides of each of the divided fluid chambers 52a to 52d made of the rubber elastic body 16 is set to be large by the elastic projections 42,42. Therefore, the internal pressure fluctuation in the divided fluid chambers 52a to 52d can be advantageously reduced or prevented from being absorbed and eliminated by the bulging deformation of the side wall portions 48, 48. Relative pressure differences between the divided fluid chambers 52a and 52b and 52c and 52d on both sides of the one elastic partition wall 44 are effectively generated. As a result, between divided fluid chambers 52a and 52b and between 52c and 52b.
During the period d, the flow amount of the fluid caused to flow through the first orifice passage 54 is increased, so that the above-described vibration damping effect based on the flow action such as the resonance action of the fluid is further enhanced. It is effective. In particular, in the present embodiment, since each elastic projection 42 is integrally connected to the first elastic partition wall 44, the rigidity of the first elastic partition wall 44 is used to make each of the divided fluid chambers 5.
The effect of improving the spring rigidity with respect to the second side wall portion 48 can be more advantageously exerted.

Further, since the elastic projections 42, 42 are formed at positions radially outwardly of the inner tube fitting 12 and the flange portion 24 formed integrally therewith, the inner and outer tube members are provided when a radial load is input. Even when the metal fittings 12 and 14 are relatively displaced in the radial direction, the relative displacement amount of the elastic projection 42 in the radial direction with respect to the bracket metal 20 can be suppressed to be small. As a result, the elastic projection 42 and the bracket 2
0 (the contact protrusion 62), the amount of relative rubbing displacement at the contact surface is reduced, and the wear and the like of the elastic protrusion 42 are suppressed, so that excellent durability is exhibited and the objective is achieved. This makes it possible to stably obtain the initial vibration isolation characteristics over a long period of time.

Also, the elastic projections 42, 42
2 and the flange portion 24 integrally formed therewith are formed at positions radially outwardly displaced, so that the inner and outer cylindrical metal fittings 1 are formed.
When an axial load is input between the inner and outer cylinders 2 and 14,
The elastic projections 42, 42 are not directly compressed between the two. Therefore, the effect on the axial spring characteristics and the vibration isolation characteristics of the strut mount 10 due to the provision of the elastic projections 42 can be prevented as much as possible. The effect of improving the vibration isolation characteristics as described above by the projections 42 can be obtained.

The strut mount 1 of the present embodiment
0, the flange portion 24 formed integrally with the inner cylinder fitting 12
However, since it is spaced apart and opposed to the contact protrusion 62 of the bracket fitting 20 in the axial direction, when an excessive load is input in the bound direction (the direction of compressing the shock absorber). Also, the abutment of the flange portion 24 against the bracket fitting 20 limits the relative displacement of the inner and outer tubular fittings 12 and 14 in the axial direction, and thus the deformation of the rubber elastic body 16, thereby providing an effective fail-safe function. And an improvement in durability.

Further, a twisting load is applied to the strut mount 10 between the inner cylindrical fitting 12 and the outer cylindrical fitting 14 due to the swinging of the suspension arm and the like. Inner and outer cylinder fittings 1
In one plane extending in the left-right direction of the vehicle including the center axes of the inner and outer cylindrical fittings 12, 14 in a twisting direction in which the respective intermediate shafts are relatively inclined in many cases. There, the elastic projection 42 is not formed near the prying plane, and both axial end faces of the rubber elastic body 16 are opposed to the bracket fitting 20 (the contact protruding portion 62) in the axial direction. Because of this, in the twisting direction, the influence of the elastic projections 42 is avoided, and low spring characteristics can be advantageously secured. As a result, good vibration isolation performance and ride comfort can be realized. Becomes

Although the first embodiment of the present invention has been described in detail above, the present invention is not to be construed as being limited by the specific description in the embodiment.

For example, the passage length and passage cross-sectional area of the first orifice passage are appropriately changed according to the required vibration isolating characteristics, and the structure of the first orifice passage is also required. It can be appropriately changed according to the size, size, shape, and the like. Specifically, for example, as shown in FIGS. 6 and 7, a pair of pocket-shaped recesses 40 a located on both sides of the first elastic partition wall 44 with respect to the intermediate sleeve 36 are formed. A pair of second orifice passages 68 is formed by forming a concave groove 66 extending in the circumferential direction across the space between 40b and 40c and 40d, and covering the concave groove 66 with the outer metal fitting 14. It is also possible to form

In the pair of second orifice passages, the ratio between the passage sectional area and the passage length can be made different from each other, so that the pair of second orifice passages can be differently tuned. And thereby
For example, as shown in FIG. 8, a high dynamic spring due to anti-resonance generated in a high frequency range rather than a low dynamic spring effect region by one first orifice passage is reduced by the other first orifice passage. It is also possible to suppress vibration by the dynamic spring effect and to improve the vibration isolation characteristics over a wide frequency range. In FIG. 8, the dashed line is a characteristic diagram when the same tuning is applied to the pair of second orifice passages, and the solid line is the other second orifice passage so as to suppress the anti-resonance. Only the second orifice passage,
It is a characteristic diagram at the time of tuning to a slightly high frequency range.

Further, each of the divided fluid chambers 52a and 52c located on both sides of each of the second elastic partition walls 46 is provided.
It is also possible to form a third orifice passage extending between the two and between 52b and 52d. The third orifice passage is desirably tuned differently from the second orifice passage,
Thereby, for example, it becomes possible to obtain an anti-vibration effect based on the resonance action of the fluid caused to flow through the third orifice passage against input vibration in the vehicle front-rear direction different from input vibration in the vehicle lateral direction. .

Further, in the above embodiment, the elastic projection 42
Is connected to the first elastic partition wall 44, but such elastic projections may be formed in the side walls 48, 48 of each of the divided fluid chambers 52 at positions separated from the first elastic partition wall. .

In the above embodiment, the elastic projection 42
Although the elastic projection 42 is in contact with the bracket 20, the elastic projection 42 may be in contact with a contact protrusion integrally formed with the outer cylinder 14, or may be directly in contact with the body 22. is there.

In addition, in the above-described embodiment, a specific example in which the present invention is applied to a strut mount for an automobile is shown. However, the present invention is also applicable to various other types such as a body mount, a differential mount, and an engine mount for an automobile. Any of these can be appropriately applied to the fluid-filled cylindrical mount according to the required characteristics.

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 in the scope of the present invention without departing from the spirit of the present invention.

[0059]

As is apparent from the above description, in the fluid-filled cylindrical mount having the structure according to the present invention, the bulging deformation on the axial side walls of the divided fluid chambers is suppressed by the elastic projections. Thus, the vibration damping effect based on the flow action of the fluid through the first orifice passage is improved, and the vibration damping performance in the direction perpendicular to the axis is improved. In addition, since the elastic projection is formed at a position deviating from the shaft member toward the outer peripheral side, remarkable increase in rigidity of the axial spring due to the elastic projection is avoided, and the vibration damping performance in the axial direction is advantageously secured. At the same time, the frictional displacement of the elastic projections at the time of vibration input in the direction perpendicular to the axis is reduced, and excellent durability is realized. Further, in addition to the elastic projection being formed at a position deviating from the shaft member to the outer peripheral side and being formed by being divided in the circumferential direction so as not to cover the second elastic partition wall, In the twisting direction on the radial plane in which the two elastic partition walls extend, it is possible to avoid a high spring due to the elastic projection, and to exhibit excellent vibration isolation performance in the twisting direction.

Therefore, according to the present invention, as a whole, different vibration damping characteristics can be easily set in the radial direction perpendicular to each other, and excellent vibration damping characteristics in the axial direction and the twisting direction can be obtained. While realizing, it is possible to further improve the vibration damping effect based on the flow action of the fluid exerted against the input vibration in the direction perpendicular to the axis, easily and with excellent durability. A fluid-filled cylindrical mount with excellent overall performance can be advantageously realized.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a strut mount for a vehicle as a first embodiment of the present invention.

FIG. 2 is a side view of the strut mount shown in FIG.

FIG. 3 is a sectional view taken along the line III-III in FIG.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is an explanatory longitudinal sectional view corresponding to a section taken along line VV in FIG. 1, showing a mounting state of the strut mount shown in FIG. 1;

FIG. 6 is a cross-sectional view showing a strut mount for a vehicle as another embodiment of the present invention.

FIG. 7 is a sectional view taken along the line VII-VII in FIG.

FIG. 8 is a graph showing a result of measuring a frequency characteristic of a dynamic spring constant in a strut mount for an automobile as another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Strut mount 12 Inner cylinder fitting 14 Outer cylinder fitting 16 Rubber elastic body 20 Bracket fitting 24 Flange part 26 Restriction block 42 Elastic projection 44 First elastic partition wall 46 Second elastic partition wall 52 Divided fluid chamber 54 First orifice Passage 62 Contact projection

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tetsu Ogawa 1-4-1 Chuo, Wako-shi, Saitama Prefecture Inside Honda R & D Co., Ltd. (72) Takuya Yanagita 1-4-1 Chuo, Wako-shi, Saitama F-term in Honda R & D Co., Ltd. (reference) 3D001 AA19 DA08 DA10 DA13 3J047 AA03 AB01 CA06 DA01 FA04 GA01 GA03

Claims (9)

[Claims] An outer cylinder member attached to the other member connected to the vibration-proof connection is disposed radially outwardly of a shaft member attached to one member connected to the vibration-proof connection. While connecting the member and the outer cylinder member with a rubber elastic body,
The walls on both sides in the axial direction are formed of the rubber elastic body to form a fluid chamber extending in the circumferential direction between the shaft member and the outer cylindrical member, and such a fluid chamber is formed from the shaft member to the outer cylindrical member. A pair of first elastic partition walls extending radially both sides toward the outer cylindrical member, and a pair of first elastic partition walls extending radially opposite to the pair of first elastic partition walls from the shaft member toward the outer cylindrical member. The first elastic partition wall is divided by two elastic partition walls to form four divided fluid chambers each filled with an incompressible fluid, and two divided fluid chambers are located on both sides of the pair of first elastic partition walls. In a fluid-filled cylindrical mount provided with a pair of first orifice passages that respectively communicate the divided fluid chambers with each other, a shaft is provided on both axial side walls of each of the divided fluid chambers formed of the rubber elastic body. Projecting outward in the circumferential direction The elastic projection extending in the axial direction is formed at a position deviated to the outer peripheral side from the shaft member in the axial direction, so as not to cover the pair of second elastic partition walls, and between the members to be vibration-isolated. The fluid-filled cylindrical mount is characterized in that, in the mounted state, the protruding tip surfaces of the elastic projections are brought into contact with the member on the side to which the outer cylindrical member is attached. 2. The fluid-filled cylindrical mount according to claim 1, wherein the pair of first elastic partition walls has a thickness smaller in a circumferential direction than the second elastic partition wall. 3. At least one axial end of the shaft member is integrally formed with a flange-like portion protruding on the outer peripheral surface, and the flange-like portion is formed of the rubber elastic body of the fluid chamber. 3. The fluid-filled cylindrical mount according to claim 1, wherein the elastic projection is formed at a position off the outer peripheral side from the flange-shaped portion when projected in the axial direction, while being fixed to the axial wall. 4. At least one of the pair of first elastic partition walls and the pair of second elastic partition walls has a diameter from at least one side of the shaft member and the outer cylinder member to the other side. The fluid-filled cylindrical mount according to any one of claims 1 to 3, further comprising a rigid restraining projection protruding in the direction. 5. The wall of each of the two divided fluid chambers, wherein the elastic projection is located on both circumferential sides of the first elastic partition wall so as to straddle each of the first elastic partition walls. The fluid-filled cylindrical mount according to any one of claims 1 to 4, wherein a pair is formed so as to be continuous in the circumferential direction over the range. 6. A cylindrical bracket attached to the other member to be connected for vibration isolation, wherein the outer cylindrical member is internally fitted and fixed to a cylindrical portion of the bracket, and both axial opening portions of the bracket are provided. The fluid according to any one of claims 1 to 5, wherein an annular contact protruding portion extending radially inward from the body is integrally formed, and the protruding distal end surface of the elastic projection is brought into contact with the contact protruding portion. Enclosed cylindrical mount. 7. A low dynamic spring effect based on the resonance effect of the fluid is exerted in one of the pair of first orifice passages in a frequency range in which the anti-resonance effect of the fluid flowing through the other orifice passage is generated. The fluid-filled cylindrical mount according to any one of claims 1 to 6, which is tuned so as to be adjusted. 8. A pair of second orifice passages respectively connecting two divided fluid chambers located on both sides of the pair of second elastic partition walls with each other. The fluid-filled cylindrical mount according to any one of the above. 9. A piston rod of an automobile shock absorber is fixed to the shaft member, and a cylindrical bracket is externally fitted and fixed to the outer cylinder member.
By fixing the outer cylinder member to the body side of the vehicle via the bracket, the axial directions of the shaft member and the outer cylinder member are set substantially in the vertical direction of the vehicle, and the pair of first elastic partition walls is provided. And the pair of second elastic partition walls are mounted on the vehicle in a state of extending in the front-rear direction and the left-right direction of the vehicle, while the bracket is formed integrally with the bracket by being formed radially inward from both axial openings on both sides in the axial direction. The abutting projection is brought into contact with the projecting distal end surface of the elastic projection, and a flange-like portion projecting on the outer peripheral surface is integrally formed at an axially upper end of the shaft member, thereby forming the rubber elastic body. And the flange-shaped part is axially separated from and opposed to a contact protruding part integrally formed at the axially upper opening of the bracket. At least in the axial direction In shadow, the fluid-filled cylindrical mount according to the elastic projections to any one of claims 1 to 8 is provided at a position deviated to the outer peripheral side from the flange portion.