JPH1078076A - Fluid-charging cylindrical mount - Google Patents

Abstract

PROBLEM TO BE SOLVED: To compatibly exercise both effective vibration isolating performance and supporting performance, even in case of inputting both a vibration load which is applied to a mount in axial right angle direction, to be vibration isolated, and a support load, acting between connected units, respectively and mutually displaced in a peripheral direction. SOLUTION: In a support rubber elastic unit 16 connecting an inner/outer cylinder metal fitting 12, 14, by making each elastic deformation characteristic of an axial direction intermediate part constituting peripheral direction both side wall parts 40, 42 of a pressure receiving chamber 62 and of an axial direction both side parts constituting axial direction both side wall parts of the pressure receiving chamber 62, different from each other, a load input direction: Q easily influencing a pressure change to the pressure receiving chamber 62 in the concerned axial direction intermediate part and a load input direction: R with generation difficult of tensile deformation in the axial direction both side parts are set to be displaced by a prescribed angle: θ mutually in a peripheral direction.

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 a vibration damping effect based on the flow of fluid between a pressure receiving chamber and an equilibrium chamber, and more particularly to a fluid-tight cylinder mount which is applied in a direction perpendicular to the axis. The present invention relates to a fluid-filled cylindrical mount that is preferably used when the vibration load to be shaken and the support load acting between connected bodies are mounted so as to be shifted from each other in the circumferential direction.

[0002]

2. Description of the Related Art Conventionally, Japanese Patent Publication No. 5-55739 and Japanese Unexamined Patent Publication No. Hei 5-55739 show a type of a vibration isolator which is interposed between connected bodies constituting a vibration transmission system and connects the connected bodies with vibration isolation. 1-1116329, US Patent No. 46903
As described in No. 89 and the like, a supporting rubber elastic body is interposed between one side of the shaft fitting and the outer cylindrical fitting spaced apart from the outer fitting in a direction perpendicular to the axis. By mounting a slit on the other side and axially penetrating in the circumferential direction and extending in the circumferential direction, the shaft fitting and the outer cylinder fitting are connected substantially only on one side by a supporting rubber elastic body, while the shaft fitting is provided. A wall is formed of a supporting rubber elastic body, a non-compressible fluid is sealed, a pressure receiving chamber into which vibration is input is formed, and a slit between the shaft fitting and the outer cylinder fitting is formed between the outer cylinder fitting and the outer cylinder fitting. A fluid-filled cylindrical type having a structure in which an incompressible fluid is sealed, an equilibrium chamber whose volume change is allowed is formed, and an orifice passage connecting the pressure receiving chamber and the equilibrium chamber to each other is formed on the side of the forming section. Mounts are known.

[0003] Such a cylindrical mount is mounted on each of the connected bodies in which the shaft fitting and the outer cylindrical fitting are vibration-isolated and mounted between the connected bodies, but the shaft fitting is attached to the outer cylindrical fitting by an input load. By being mounted so as to be displaced toward the supporting rubber elastic body side, the generation of tensile stress in the supporting rubber elastic body is reduced by the slit, and excellent durability is exhibited. An effective vibration damping effect is exerted on the basis of a flow action such as a resonance action of the fluid caused to flow through the orifice passage.

In such a fluid-filled cylindrical mount, the vibration load to be damped and the support load applied between the connected bodies are all applied in the direction perpendicular to the axis. In the case of adoption as an engine roll mount for automobiles, the input direction of the vibration load and the input direction of the support load may be displaced in the circumferential direction without being matched with each other in the mounted state. In the description above and below, the support load of the mount is, in principle,
It refers to an external load as a resultant force of all loads exerted on the mount, such as an engine load and a roll load, or a torque load and a vibration load, in the engine roll mount.

However, in the conventional fluid-filled cylindrical mount, due to its structure, the difference between the input directions of the vibration load and the support load is not taken into consideration. For example, when the vibration load is input, the internal pressure of the pressure receiving chamber changes. When the mount mounting direction is determined so that the vibration is effectively generated and the vibration isolation effect based on the fluid flow action through the orifice passage is advantageously exerted, a tensile stress is generated in the supporting rubber elastic body by the input of the supporting load. In some cases, durability may be insufficient, or effective support spring characteristics may not be exhibited, and it has been difficult to achieve both effective vibration isolation performance and support spring characteristics based on the fluid flow action. .

[0006]

Here, the inventions according to claims 1 to 5 (hereinafter, referred to as the present invention) are all made on the background of the above-described circumstances, and the vibration load and the vibration load under the mounted state are all reduced. Even when the input directions of the supporting loads do not coincide with each other, a new structure that achieves a high degree of compatibility between the anti-vibration performance based on the fluid flow action and the effective supporting spring characteristics with a simple structure. It is an object to provide a fluid-filled cylindrical mount.

[0007]

In order to solve such a problem, a feature of the invention according to claim 1 is that a shaft member and an outer cylinder member spaced apart from the shaft member are provided. A support rubber elastic body is interposed on one side of the shaft member sandwiched in the direction perpendicular to the axis, and a slit is formed on the other side so as to penetrate in the axial direction and expand in the circumferential direction. The outer cylindrical member is substantially connected only on the one side by the supporting rubber elastic body, while the both side walls in the axial direction and the circumferential direction are provided between the shaft member and the outer cylindrical member by the supporting rubber elastic member. A non-compressible fluid is enclosed by the body, and forms a pressure receiving chamber to which vibration is input, and an incompressible fluid is provided on the slit forming side between the shaft member and the outer cylinder member. To form an equilibrium chamber that is Further, in the fluid-filled cylindrical mount, which is provided with an orifice passage for communicating the pressure receiving chamber and the equilibrium chamber with each other, and the shaft member and the outer cylindrical member are attached to each one of the connected bodies to be vibration-isolated. The elastic deformation characteristics of the support rubber elastic body in the direction perpendicular to the mount axis are defined by an axial intermediate portion forming the circumferential side walls of the pressure receiving chamber, and an axial side portion forming the axial both side walls of the pressure receiving chamber. Thus, a load input direction that easily causes a pressure change in the pressure receiving chamber at the axially intermediate portion of the support rubber elastic body and a tensile deformation at both axial side portions of the support rubber elastic body are generated. The load input direction which is difficult to be set is set to be shifted from each other in the circumferential direction.

[0008] In the fluid-filled cylindrical mount having the structure according to the first aspect of the present invention, the support rubber elastic body is elastically deformed when a load is applied and acts like a piston on the pressure receiving chamber. And the axial middle part, which causes pressure fluctuations in the pressure receiving chamber, and both axial parts, which exert little spring-like action on the pressure receiving chamber when load is applied, but can exhibit effective spring rigidity when load is input In contrast, the respective elastic deformation characteristics are provided under different design ideas. In the axially intermediate portion, the shape and the like are designed in consideration of the load input direction that easily causes a pressure change in the pressure receiving chamber based on the action of the piston. The shape and the like are designed based on a load input direction that can exert an effective elastic supporting force while suppressing the generation of tensile stress.

Therefore, in the fluid-filled cylindrical mount having the structure according to the first aspect of the present invention, even if the input direction of the vibration load and the input direction of the support load at the time of mounting are different, the input of the vibration load is performed. Design the shape of the intermediate portion of the supporting rubber elastic body in the axial direction so that an effective pressure change is generated in the pressure receiving chamber, and adjust the supporting rubber elastic body so that the generation of tensile stress when the supporting load is input is suppressed. It is possible to set the shape and the like of both sides in the axial direction, thereby achieving a high level of compatibility between the vibration-proofing effect based on the fluid flow action and the durability of the supporting rubber elastic body. It is.

In the fluid-filled cylindrical mount having the structure according to the first aspect of the present invention,
The load input direction in which tensile deformation is unlikely to occur on both axial portions of the support rubber elastic body is set on the substantially circumferential center line of the support rubber elastic body, while the pressure receiving chamber is set on one side in the circumferential direction of the support rubber elastic body. And the pressure-receiving chamber located on one side in the circumferential direction is made thinner at one circumferential side wall than the other circumferential side wall. A configuration in which the input direction is shifted to one of the thinner circumferential side wall portions with respect to the load input direction in which tensile deformation is unlikely to be generated in both axial portions of the supporting rubber elastic body is preferably adopted. Is done.

By employing such a configuration, it is possible to more reliably prevent the occurrence of tensile deformation at both axial sides of the supporting rubber elastic body while sufficiently securing the pressure change in the pressure receiving chamber when the vibration load is input. Extremely excellent durability can be obtained by reducing or preventing it.

The invention described in claim 2 is the first invention.
In the fluid-filled cylindrical mount having a structure according to the invention described in (1), a vibration load to be subjected to vibration damping is input in a load input direction in which a pressure change is likely to be exerted on the pressure receiving chamber at an axially intermediate portion of the support rubber elastic body. On the other hand, a support load acting between the connected members is input in a load input direction in which tensile deformation is hardly generated in both axial portions of the support rubber elastic body. .

In the fluid-filled cylindrical mount having the structure according to the second aspect of the present invention, the amount of fluid that can flow through the orifice passage when a vibration load is input is advantageously secured, and the fluid flow The anti-vibration effect based on the action is effectively exhibited, and the generation of tensile stress due to the supporting load is reduced or prevented, and the generation of cracks and the like in the supporting rubber elastic body is suppressed, and the durability of the mount is advantageously secured. It is done.

Further, in order to solve the above-mentioned problem, a feature of the present invention according to claim 3 is that a shaft member and an outer cylinder member spaced apart from the shaft member are provided. A support rubber elastic body is interposed on one side of the shaft member that is sandwiched in the direction perpendicular to the axis, and a slit that penetrates in the axial direction and extends in the circumferential direction is provided on the other side. While the cylindrical member is substantially connected only on the one side by the support rubber elastic body, both side walls in the axial direction and the circumferential direction are provided between the shaft member and the outer cylindrical member by the support rubber elastic body. And a pressure receiving chamber into which vibration is input, in which an incompressible fluid is sealed, and an incompressible fluid is sealed on the side of the slit forming portion between the shaft member and the outer cylinder member. To form an equilibrium chamber where volume changes are allowed Further, in the fluid-filled cylindrical mount, which is provided with an orifice passage for communicating the pressure receiving chamber and the equilibrium chamber with each other, and the shaft member and the outer cylindrical member are attached to each one of the connected bodies to be vibration-isolated. In the axially intermediate portion of the support rubber elastic body where the pressure receiving chamber is provided, a load input direction in a direction perpendicular to the axis at which compression and shear stress on both sides in the circumferential direction are substantially equal at the time of load input; Such support is achieved by making the load input directions in the direction perpendicular to the axis at which the compressive and shear stresses on both sides in the circumferential direction become substantially equal at the time of load input in the axial side portions forming the circumferential side walls of the pressure receiving chamber. The elastic deformation characteristics of the rubber elastic body in the direction perpendicular to the mount axis are different between the intermediate portion in the axial direction and the both side portions in the axial direction.

Note that the compressive and shear stresses are not the stresses per unit cross-sectional area but the total stresses generated in all the regions located on both sides in the circumferential direction with respect to the load input direction line.

In the fluid-filled cylindrical mount having the structure according to the third aspect of the present invention, in the axially intermediate portion of the support rubber elastic body, the axial and compressive shear forces on both sides in the circumferential direction are substantially equal. When a load is input in the perpendicular direction, elastic deformation toward the pressure receiving chamber is efficiently generated, and an effective pressure change is generated in the pressure receiving chamber.On the other hand, on both axial sides of the support rubber elastic body, When a load is input in a direction perpendicular to the axis at which the compressive and shear stresses on both sides in the circumferential direction are substantially equal, excellent load supporting characteristics are exhibited by effective spring rigidity while suppressing generation of tensile stress.

Therefore, the fluid-filled cylindrical mount having the structure according to the third aspect of the present invention is mounted similarly to the fluid-filled cylindrical mount having the structure according to the first aspect of the present invention. Even when the input direction of the vibration load and the input direction of the support load at the time are different, the vibration isolation effect based on the fluid flow action and the effective load support characteristics can both be achieved at a high level.

In the fluid-filled cylindrical mount according to any one of the first to third aspects, for example, a step is formed between the axially intermediate portion and the axially opposite side portion on both circumferential sides of the support rubber elastic body. It is also possible to make the elastic deformation characteristics of the intermediate portion in the axial direction and the both side portions in the axial direction different from each other, but from the viewpoint of the moldability and durability of the supporting rubber elastic body, the slit is mounted on the mounting shaft. By forming a substantially constant cross-sectional shape over the entire length in the direction, the circumferential side surfaces of the support rubber elastic body are flattened in the axial direction as a whole in the axial middle portion and the axial both side portions, and formed in the axial middle portion. By appropriately setting the shape of the pressure receiving chamber and the shape of the inner and outer surfaces in the axial direction on both sides in the axial direction, the elastic deformation characteristics in the axial intermediate portion and the axial both sides can be made different from each other. Hope There.

Further, in order to solve the above-mentioned problem, a feature of the present invention according to claim 4 is that a shaft member and an outer cylindrical member which is spaced apart from the shaft member are provided. A support rubber elastic body is interposed on one side of the shaft member that is sandwiched in the direction perpendicular to the axis, and a slit that penetrates in the axial direction and extends in the circumferential direction is provided on the other side. While the cylindrical member is substantially connected only on the one side by the support rubber elastic body, both side walls in the axial direction and the circumferential direction are provided between the shaft member and the outer cylindrical member by the support rubber elastic body. And a pressure receiving chamber into which vibration is input, in which an incompressible fluid is sealed, and an incompressible fluid is sealed on the side of the slit forming portion between the shaft member and the outer cylinder member. To form an equilibrium chamber where volume changes are allowed Further, in the fluid-filled cylindrical mount, which is provided with an orifice passage for communicating the pressure receiving chamber and the equilibrium chamber with each other, and the shaft member and the outer cylindrical member are attached to each one of the connected bodies to be vibration-isolated. The slit has a substantially constant cross-sectional shape over the entire length in the mount axial direction, and a concave or projecting thickened portion is formed in a circumferentially intermediate portion of both axial end surfaces of the support rubber elastic body. By displacing the center in the circumferential direction with respect to the center in the circumferential direction of the pressure receiving chamber in the circumferential direction, the elastic deformation characteristics of the support rubber elastic body in the direction perpendicular to the mount axis can be reduced. And the axially opposite side portions of the pressure receiving chamber that constitute the axially opposite side walls are different from each other.

In the fluid-filled cylindrical mount having the structure according to the fourth aspect of the present invention, the axially intermediate portion of the supporting rubber elastic body causes an effective pressure change in the pressure receiving chamber due to elastic deformation. The load input direction to be obtained can be adjusted by appropriately setting the center in the circumferential direction of the pressure receiving chamber. On the other hand, the appropriate spring stiffness due to both side walls in the axial direction of the supporting rubber elastic body reduces the local concentration of stress and the like. The load input direction exerted without accompanying can be adjusted by appropriately setting the circumferential center of the uneven thickness portion.

Since the center of each of the pressure receiving chamber and the uneven thickness portion in the circumferential direction can be set independently of each other and shifted from each other in the circumferential direction, the input direction of the vibration load to be damped is taken into consideration. By setting the center of the pressure receiving chamber in the circumferential direction, and by setting the center of the uneven thickness portion in the circumferential direction in consideration of the input direction of the support load acting between the connected bodies, the input direction of the vibration load and the support Even when the input directions are different from each other, the vibration damping effect based on the fluid flow action based on the piston-like action at the axially intermediate portion of the supporting rubber elastic body at the time of inputting the vibration load is effectively exhibited, and Thus, based on the compressive and shear stresses on both axial sides of the support rubber elastic body, appropriate support spring stiffness is exhibited with good durability while preventing local stress concentration and the like.

The center of each of the pressure receiving chamber and the uneven thickness portion in the circumferential direction is
It is sufficient that at least one of the pressure receiving chambers and the uneven thickness portion are shifted from each other in the circumferential direction by biasing at least one in the circumferential direction. The directional centers are positioned offset from each other in the circumferential direction.

The invention described in claim 5 is the same as the invention described in claim 4.
In the fluid-filled cylindrical mount having the structure according to the invention described in (1), the amount of deviation in the circumferential direction of the circumferential center of the pressure receiving chamber with respect to the circumferential center of the uneven thickness portion is different between the shaft member and the outer cylindrical member. It is characterized in that it is set in accordance with the amount of shift in the input direction of the support load acting between the connected bodies with respect to the input direction of the vibration load to be damped, which is exerted between them.

In the fluid-filled cylindrical mount having the structure according to the fifth aspect of the present invention, the vibration load to be damped is applied in a direction passing through the substantially circumferential center of the pressure receiving chamber, while the support is provided. The mounting can be performed so that the load is applied in the direction passing through the substantially circumferential center of the uneven thickness portion, whereby the piston-like action at the axially intermediate portion of the supporting rubber elastic body is more effectively exhibited. When the vibration load is input, the amount of fluid that can be made to flow through the orifice passage is advantageously ensured, so that the vibration damping effect based on the fluid flow action is more effectively exerted, and the axially opposite sides of the supporting rubber elastic body. The compression rubber stiffness is more effectively exerted, and the support spring stiffness with respect to the support load is more effectively exerted. Than it can be reserved.

By the way, in the fluid-filled cylindrical mount having the structure according to any one of the first to fifth aspects of the present invention, the supporting rubber elastic body is formed so as to have a cross section perpendicular to the axis.
As a whole, it is preferable to form it with a substantially fan-shaped cross-sectional shape that spreads from the shaft member side to the outer cylinder member side.

By adopting such a shape of the supporting rubber elastic body, it is possible to advantageously reduce or prevent the occurrence of tensile stress in the axially intermediate portion and the axially both side portions of the supporting rubber elastic body when a supporting load is input. It is possible to do.

In the fluid-filled cylindrical mount having the structure according to any one of the first to fifth aspects of the present invention, the metal sleeve is vulcanized and bonded to the outer peripheral surface of the supporting rubber elastic body. A pressure receiving chamber is formed by externally fitting and fixing the outer cylinder fitting to the sleeve, and closing the pocket portion opened to the outer peripheral surface through the window provided in the metal sleeve with the outer cylinder fitting. Of the circumferential side walls of the pressure receiving chamber in the intermediate portion, one of the circumferential side walls of the pressure receiving chamber positioned on the input side of the support load with respect to the input direction of the vibration load, in other words, the compressive stress due to the support load. In the larger circumferential side wall portion, the metal sleeve bonded to the outer peripheral surface is formed to protrude inward to form a concave groove extending in the circumferential direction, and the outer peripheral surface opening of the concave groove is formed with an outer cylinder fitting. Cover Thereby, while forming an orifice passage connecting the pressure receiving chamber and the equilibrium chamber, due to the inwardly protruding groove, the other circumferential side wall portion has a larger compressive stress than the circumferential side wall portion. The elastically deformable free length in the direction perpendicular to the axis may be set large.

If such a configuration is adopted, if a tensile stress is generated on one circumferential side wall portion where a tensile stress is likely to be generated when a supporting load is input at the axially intermediate portion of the supporting rubber elastic body. However, by increasing the free length, the amount of tensile strain generated, that is, the amount of tensile deformation per unit length or the tensile stress per unit cross-sectional area can be suppressed to a small value. The durability at the axially intermediate portion of the rubber elastic body can be advantageously secured, and the durability of the mount can be further improved.

In addition, if such a configuration is adopted, the inner protrusions (concave portions) of the metal sleeve provided to make the free lengths of the circumferential side walls at the axially intermediate portion of the supporting rubber elastic body different from each other. Since the orifice passage is formed using the groove, the orifice passage can be advantageously formed while effectively utilizing the space.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, in order to clarify the present invention more specifically, a specific example of an embodiment of the present invention will be described in detail with reference to the drawings.

First, FIGS. 1 to 3 show an automobile engine mount 10 having a structure according to the present invention.
The engine mount 10 includes an inner cylinder fitting 12 as a shaft member and an outer cylinder fitting 14 as an outer cylinder member disposed outside of the inner cylinder fitting 12 at a predetermined distance.
It is structured to be elastically connected by a supporting rubber elastic body 16 interposed between the four. By mounting the inner cylinder fitting 12 on the power unit side and the outer cylinder fitting 14 on the body side, the inner cylinder fitting 12 is interposed between the power unit and the body so that the power unit is supported on the body with vibration isolation. It has become.

More specifically, the inner cylinder fitting 12 has a straight cylindrical shape, and is fixed to the power unit side of the vehicle by bolts or the like inserted into the inner hole 18 although not shown. It has become.

A metal sleeve 20 having a large-diameter thin-walled cylindrical shape as a whole is provided radially outward of the inner cylindrical fitting 12.
The metal sleeve 20 is positioned so as to surround the inner cylindrical fitting 12 at a predetermined distance and is slightly eccentric in the radial direction with respect to the inner cylindrical fitting 12. The metal sleeve 20 has a first window portion 22 and a second window portion 24, each of which has a circumferential length that does not reach half a circumference at a central portion in the axial direction of the peripheral wall portion.
Are formed facing each other in the radial direction. The first window 22 has a slightly shorter circumferential length than the second window 24. In other words, the metal sleeve 2
Reference numeral 0 denotes a pair of annular or cylindrical ring-shaped portions 26, 26 which are arranged on the same axis at a predetermined distance in the axial direction from each other and straddle between their axially opposed surfaces. The first and second axial connecting portions are integrally connected by first and second axial connecting portions 28 and 30 extending from each other, and an opening between the axially facing surfaces of the ring-shaped portions 26 and 26 is formed by the first and second axial connecting portions. 28,
By partitioning at 30, a first window portion 22 and a second window portion 24 that are radially opposed to each other are formed.

Further, in the metal sleeve 20, the first axial connecting portion 28 is recessed inward in the radial direction, whereby the first axial connecting portion 28 is opened on the outer peripheral surface of the metal sleeve 20, and the first window portion is formed. A groove extending in the circumferential direction is formed so as to extend between the second window portion 22 and the second window portion 24. As is apparent from this, in the present embodiment, the first axial connecting portion 28 allows the other axial connecting portion (second axial connecting portion) 3
An inward projection that projects radially inward from zero is formed.

The metal sleeve 20 is externally inserted into the inner cylindrical fitting 12 and is positioned in a radial direction where the first window 22 and the second window 24 are opposed to the inner cylindrical fitting 12. Are arranged eccentrically in a state where they are separated from each other on the side of the first window portion 22 and close to each other on the side of the second window portion 24.

A groove-shaped stopper fitting 32 is provided in the metal sleeve 20 at a circumferentially intermediate portion of the second window 24.
Are provided so as to straddle between the two ring-shaped portions 26, 26, and are fixed to the inner peripheral surfaces of the ring-shaped portions 26, 26.
Then, in a state in which the groove of the stopper projects from the inner peripheral surface of the metal sleeve 20 toward the inner cylinder 12, in other words, the second window 24 of the metal sleeve 20.
The inside of the groove is positioned so as to open, and the groove bottom of the stopper fitting 32 is opposed to the inner cylinder fitting 12 at a predetermined distance in the radial direction.

Further, the inner tube fitting 12 and the metal sleeve 20
A support rubber elastic body 16 is interposed between the radially opposed surfaces of the two on the side where the separation distance between the two members 12 and 20 in the eccentric direction is large, and is added to the inner cylinder fitting 12 and the metal sleeve 20. The inner cylindrical fitting 12 and the metal sleeve 20 are elastically connected to each other by the support rubber elastic body 16. The support rubber elastic body 16 is formed so that the inner cylindrical metal fitting 12 is in contact with the metal sleeve 20 in the second window 24.
In addition to being eccentrically positioned on the side, the first window portion 22 has a smaller circumferential opening width than the second window portion 24, and has a substantially fan-shaped cross section around the first window portion 22. However, substantially, the supporting rubber elastic body 16 is interposed only between the inner cylindrical member 12 and the metal sleeve 20 on the side where the distance between the two members 12 and 20 in the eccentric direction is large. . In addition, the supporting rubber elastic body 16
Both end surfaces in the circumferential direction are substantially flat surfaces over the entire length in the axial direction, and have a substantially constant outer peripheral shape over the entire length in the axial direction.

The support rubber elastic body 16 is formed with a pocket 38 so as to hollow out the inside thereof, and the pocket 38 is formed on the outer peripheral surface through the first window 22 of the metal sleeve 20. It is opened. In short, the pocket portion 38 has a peripheral wall portion of the supporting rubber elastic body 1.
6. Further, of the peripheral wall portion of the pocket portion 38, the first peripheral side wall portion 40 and the second peripheral side wall portion which are constituted by the axially intermediate portion of the support rubber elastic body 16 and constitute the peripheral side wall portions of the pocket portion 38. The circumferential side wall portion 42 is interposed between the radially opposed surfaces of the inner cylindrical member 12 and the first axial connection portion 28 and between the radially opposite surfaces of the inner cylindrical member 12 and the second axially connected portion 30, respectively. Is equipped.

Here, the pocket portion 38 is formed such that its center position is deviated to one side in the circumferential direction with respect to the circumferential center point of the support rubber elastic body 16 in the support rubber elastic body 16. Thereby, the thickness of the second circumferential side wall portion 42 in the circumferential direction is made smaller than that of the first circumferential side wall portion 40. In other words, the inner cylinder fitting 1
The direction line passing through the load input point on the second side and the center point in the circumferential direction of the pocket portion 38 is mounted with respect to the direction line passing through the load input point on the side of the inner cylinder fitting 12 and the center point in the circumferential direction of the supporting rubber elastic body 16. It is set to be shifted by a predetermined amount toward the second circumferential side wall portion 42 in the circumferential direction.

As described above, since the pocket portion 38 is formed so as to be deviated in the circumferential direction with respect to the support rubber elastic body 16, the inner cylindrical member 12 is relatively displaced in the radial direction with respect to the outer cylindrical member 14. At this time, the first and second circumferential side wall portions 40, 4
2 is swelled and deformed inwardly of the pocket 38 so that the volume of the pocket 38 can be changed most greatly. It is shifted by a predetermined amount from the direction of the circumferential center line of the body 16 in the direction in which the pocket portion 38 is biased in the circumferential direction. In other words, when the inner cylindrical member 12 is radially displaced relative to the outer cylindrical member 14, the first circumferential side wall portion 40 and the second circumferential side wall portion 42
The relative displacement direction of the inner and outer tube fittings 12 and 14 at which the stress (compression and shear stress) generated in the inner and outer cylindrical fittings 12 and 14 at which the generation of the tensile stress becomes the smallest is determined.
Is shifted by a predetermined amount from the direction of the circumferential center line in the circumferential direction of the pocket portion 38.

The metal sleeve 20 is connected to the first axial connecting portion 2 to which the outer peripheral surface of the first circumferential side wall portion 40 is bonded.
At 8, the outer peripheral surface of the second circumferential side wall portion 42 is recessed inward in the radial direction from the second axial connection portion 30 to which the second circumferential side wall portion 42 is bonded, and the distance between the radially opposed surfaces with the inner cylindrical metal fitting 12. Is reduced, the first circumferential side wall portion 4 interposed between the inner cylindrical fitting 12 and the first axial connection portion 28 is formed.
The free length in the radial direction is set to be greater in the second circumferential side wall portion 42 interposed between the inner cylinder fitting 12 and the second axial connection portion 30 than in the case of 0. A groove 43 extending in the circumferential direction is formed on the outer peripheral surface of the first circumferential side wall portion 40 by the first axial connecting portion 28 of the metal sleeve 20.

Further, of the peripheral wall portion of the pocket portion 38,
The axial side walls 44, 44 of the pocket portion 38 formed by the axial end portions of the supporting rubber elastic body 16 have shafts whose outer peripheral portions protrude outward in the axial direction on the outer surfaces of the circumferential intermediate portions, respectively. The uneven thickness portion 50, which is a convex portion 46, and whose inner peripheral portion is an axial concave portion 48 recessed inward in the axial direction, has a circumferential length substantially equal to the circumferential length of the pocket portion 38. Have been. These uneven thickness portions 50 and 5
In the case of 0, the center in the circumferential direction is in the circumferential direction opposite to the shift direction of the pocket portion 38 with respect to the circumferential center of the supporting rubber elastic body 16, that is, in the first circumferential side wall portion 40 side. It is formed slightly shifted in the circumferential direction approaching.

As described above, since the uneven thickness portion 50 is formed in each axial side wall portion 44, the size of the radial direction support spring rigidity in the axial side wall portion 44 is adjusted. In particular, since the uneven thickness portion 50 is formed so as to be deviated in the circumferential direction of the axial side wall portion 44, the relative displacement direction in the radial direction of the inner and outer cylindrical fittings 12, 14 in which the support spring rigidity is effectively exerted is improved. The first circumferential side wall portion 40
And the two stresses (compression and shear) generated in the second circumferential side wall portion 42 are substantially equal to each other, and the thickness of the inner and outer cylindrical metal fittings 12 and 14 in which the generation of the tensile stress is minimized is uneven. It is shifted by a predetermined amount in the circumferential direction of the displacement of the portion 50. From another point of view, when the inner cylindrical member 12 is displaced relative to the outer cylindrical member 14 in the radial direction,
In the first and second circumferential side wall portions 40 and 42, stresses (compression and shear stress) generated on both sides in the circumferential direction are substantially equal, and the generation of tensile stress is minimized.
The stress (compression and shear stress) generated on both sides in the circumferential direction at the relative displacement direction of the inner and outer cylindrical fittings 12, 14 and the respective axial side walls 44, 44 is substantially equal, and the generation of tensile stress is minimized. , The relative displacement directions of the inner and outer cylindrical metal fittings 12 and 14 correspond to the pocket portion 38 and the uneven thickness portion 50.
Are set to be shifted from each other in the shift direction.

In this embodiment, the first and second circumferential side wall portions 4 having different thicknesses and free lengths from each other are provided.
In consideration of the fact that the spring characteristics of 0, 42 are exerted on the axial side wall portion 44, the uneven thickness portion 50 in the axial side wall portion 44 is considered.
Are largely displaced in the direction opposite to the displacing direction of the pocket portion 38, but the first and second circumferential side wall portions 40, 42
Due to the influence of the spring characteristic described above, the radial direction in which the effective spring stiffness is actually exerted on the axial side wall portion 44 substantially coincides with the circumferential center line of the axial side wall portion 44.

On the other hand, between the radially opposed surfaces of the inner cylinder fitting 12 and the metal sleeve 20, on the side where the distance between the two members 12, 20 in the eccentric direction is small, the supporting rubber elastic body 1 is provided.
A slit 52 extending in a portion where no 6 is interposed over substantially half a circumference in the circumferential direction is formed so as to penetrate in the axial direction. That is, since the slit 52 is formed, on the side where the separation distance in the eccentric direction between the inner cylinder fitting 12 and the metal sleeve 20 is small, the connection between the two members 12 and 20 by the supporting rubber elastic body 16 is cut off. In this state, the members 12 and 20 are not substantially connected by the supporting rubber elastic body 16. In addition,
On the outer peripheral surface of the inner cylinder fitting 12, a first cushion rubber projection 54 projecting toward the slit 52 is integrally formed by the support rubber elastic body 16.
The inner cylinder fitting 12 is brought into contact with the stopper fitting 32 through the through hole, so that a stopper function in the rebound direction is exhibited.

In the metal sleeve 20, a bag-like rubber elastic body 56 having a shallow bottom bag shape is provided at a portion where the second window 24 located on the slit 52 side is formed. The bag-like rubber elastic body 56 is
0, the second window 24 is vulcanized and bonded so as to cover the inner window from the inner peripheral side, so that the bag 58 of the bag-shaped rubber elastic body 56 passes through the second window 24. It is opened on the outer peripheral surface of the metal sleeve 20. Further, at one end in the circumferential direction, the bag portion 58 is formed with a pocket portion 38 formed in the support rubber elastic body 16 by a concave groove 43 formed by the first axial connection portion 28 of the metal sleeve 20. It is connected to the.

A contact portion 60 protruding from the center of the bottom of the stopper fitting 32 toward the second window portion 24 is formed integrally with the bag-like rubber elastic body 56 at the center of the bag portion 58. . Further, the bag-shaped rubber elastic body 56 is formed integrally with the supporting rubber elastic body 16 and, for example, the inner cylindrical metal fitting 12.
A rubber material is filled in a rubber vulcanization mold in which the metal sleeve 20 is set, and the support rubber elastic body 16 and the bag-like rubber elastic body 56 are integrally vulcanized and molded.

Then, the outer tube fitting 14 is externally inserted into such an integrally vulcanized molded product, and is fitted and fixed to the outer peripheral surface of the metal sleeve 20 by an eight-way drawing process or the like. Thereby, the openings of the pocket portion 38 and the bag portion 58 are covered with the outer tube fitting 14, and the pressure receiving chamber 62 and the equilibrium chamber 64 in which a predetermined incompressible fluid is sealed are formed. The orifice passage 43 is covered with the outer tube fitting 14 and communicates the pressure receiving chamber 62 and the equilibrium chamber 64 with each other.
6 are formed. A thin seal rubber layer 68 is formed on the inner peripheral surface of the outer tube fitting 14 over substantially the entire surface, and the seal rubber layer 68
The fluid tightness of the sealed fluid is ensured by being sandwiched between the outer casing 14 and the outer tube fitting 14. Further, as the sealed fluid, water, alkylene glycol, polyalkylene glycol, silicone oil and the like can be suitably used,
In particular, a low-viscosity fluid of 0.1 Pa · s or less is advantageously employed in order to advantageously obtain a vibration damping effect based on the resonance action of the fluid.

Here, the pressure receiving chamber 62 has a peripheral wall portion formed of the supporting rubber elastic body 16, and the inner and outer cylindrical metal fittings 12,
When a vibration is input to the space 14, the internal pressure fluctuation is caused based on the elastic deformation of the support rubber elastic body 16.
On the other hand, the volume of the equilibrium chamber 64 can be easily changed based on the elastic deformation of the bottom wall and the peripheral wall formed of the bag-shaped rubber elastic body. Accordingly, when vibration in the radial direction is input between the inner and outer cylinder fittings 12 and 14, the orifice passage 66 passes between the two chambers 62 and 64 based on the relative internal pressure difference between the pressure receiving chamber 62 and the equilibrium chamber 64. Fluid flow is generated, so that a vibration damping effect based on a fluid action such as a resonance action of the fluid is exerted.

A stopper block 70 is accommodated in the pressure receiving chamber 62, is fitted into the first window 22 of the metal sleeve 20, and is supported by the outer peripheral surface of the outer sleeve 14. The stopper block 70
The protruding tip surface protrudes into the pressure receiving chamber 62, and is fixedly supported in a state where the protruding distal end face is opposed to the bottom surface of the pressure receiving chamber 62 at a predetermined distance. Then, the stopper block 70 is brought into contact with the inner cylinder fitting 12 via the second cushion rubber projection 72 formed on the side surface of the pressure receiving chamber 62 so that the stopper function in the bound direction is exhibited. It has become.

In the engine mount 10 having such a structure, the inner metal fitting 12 is mounted on the power unit side.
The outer tube fittings 14 are attached to the body side, respectively.
It is interposed between the power unit and the body, and in such a mounted state, the vibration load required for vibration proof performance and the support spring rigidity are required between the inner cylinder fitting 12 and the outer cylinder fitting 14. And the supporting load to be applied. In this embodiment, the vibration load is mainly an engine roll vibration, and the support load is a large input load as a resultant of an external load such as a power unit load.

Further, as shown in FIG. 1, the vibration load: Q and the supporting load: R
Due to the support structure of the power unit and the like, input is made between the inner and outer cylindrical metal fittings 12 and 14 in the radial direction shifted from each other by a predetermined angle: θ in the circumferential direction of the mount.

Here, the engine mount 1
0 indicates that the stresses (compression and shear stress) generated on both sides in the circumferential direction in the first and second circumferential side wall portions 40 and 42 are substantially equal and the generation of tensile stress is minimized. The relative displacement direction of the inner and outer cylindrical metal fittings 12, 14 at which the stress (compression and shear stress) generated on both sides in the circumferential direction at each axial side wall 44, 44 becomes substantially equal and the generation of tensile stress is minimized. The amount of deviation in the circumferential direction from the relative displacement direction is the above vibration load: Q
In the circumferential direction between the input direction and the support load: R. The inner and outer cylindrical metal fittings 1 in which the stress (compression and shear stress) generated on both sides in the circumferential direction in the first and second circumferential side wall portions 40 and 42 are substantially equal and the generation of tensile stress is minimized.
The relative displacement directions of the shafts 2 and 14 substantially coincide with the input direction of the vibration load: Q, and the stresses (compression and shear stress) generated on both sides in the circumferential direction in the axial side walls 44 and 44 become substantially equal. In addition, the inner and outer cylindrical fittings 12, 14 at which the generation of tensile stress is minimized are mounted between the power unit and the body in a state in which the relative displacement direction substantially coincides with the input direction of the supporting load: R.

In the engine mount 10 mounted in such a direction, the input direction of the vibration load: Q changes in the volume of the pocket 38 due to the relative displacement of the inner and outer cylindrical fittings 12 and 14, and thus the pressure in the pressure receiving chamber 62. Is set to the relative displacement direction of the inner and outer cylindrical fittings 12 and 14 that can be generated very effectively. Therefore, when the vibration load: Q is input, a sufficient amount of fluid is allowed to flow through the orifice passage 66, and the fluid The vibration damping effect based on the flow action such as the resonance action can be advantageously exhibited.

On the other hand, in the engine mount 10, the input direction of the support load: R is such that the support spring elasticity of the support rubber elastic body 16 (axial side walls 44, 44) is extremely effectively exerted. Because of the relative displacement directions of 12, 14, when the support load: R is input, the desired support spring stiffness is exhibited, and the occurrence of tensile stress is reduced or prevented, resulting in excellent durability. Is exhibited.

In this example, the vibration load: Q
Since the input direction of the support load: R is shifted toward the first circumferential side wall portion 40 with respect to the input direction of the support rubber elastic body 16, the input of the support load: R Occasionally, tensile deformation is likely to occur in the second circumferential side wall portion 42, particularly in the outer peripheral portion restrained by bonding to the metal sleeve 20, but as described above, the second circumferential side wall portion 42 Since the free length in the radial direction is set to be larger than that of the first circumferential side wall portion 40, the amount of distortion with respect to the relative displacement amount of the inner and outer cylindrical metal fittings 12 and 14 can be reduced. Assuming that the second circumferential side wall portion 4
2, even when tensile deformation occurs, the amount of strain and, consequently, tensile stress are suppressed, and excellent durability is exhibited.

In this example, the intersection angle (center angle) between the first circumferential side wall portion 40 and the second circumferential side wall portion 42 is α.
Is set to be smaller than 180 degrees, and the supporting rubber elastic body 1
Because the fan 6 has a fan-shaped cross section perpendicular to the axis, even if the input direction of the vibration load: Q is shifted in the circumferential direction with respect to the input direction of the support bracket: R, the engine mount 10 is inclined and disposed. The occurrence of tensile deformation in the second circumferential side wall portion 42 is further advantageously suppressed.

In addition, in this specific example, a stopper mechanism in both directions of the bound and the rebound is provided to prevent excessive relative displacement of the inner and outer cylindrical fittings 12 and 14 and hence excessive elastic deformation of the support rubber elastic body 16. From that
Thereby, the occurrence of tensile deformation in the support rubber elastic body 16 is reduced, and the durability is improved.

In this embodiment, the axial side walls 44,
Not only at 44 but also at the intermediate portion in the axial direction of the supporting rubber elastic body 16, the metal sleeve 20 is provided with a radially effective free length in the first circumferential side wall portion 40 in which the sharing of the power unit supporting load is increased. The first circumferential side wall portion 40 provides effective support spring rigidity because the first circumferential side wall portion 40 is reduced in size by the concave portion inward in the radial direction.

Moreover, the engine mount 10 of this specific example
In order to shorten the effective free length in the radial direction of the first circumferential side wall portion 40, the first circumferential side wall portion is provided by using a radially inward recessed portion provided in the metal sleeve 20. A space for forming the orifice passage 66 can be advantageously secured between the outer peripheral surface of the outer casing 40 and the outer cylinder fitting 14,
There is also the advantage that the orifice passage 66 can be formed with effective space efficiency and a simple structure.

Although one specific example of the present invention has been described in detail above, this is a literal example, and the present invention is not construed as being limited to such specific example.

For example, when the mount is arranged obliquely, the support rubber elastic body 16 is provided on the side where the inner cylinder 12 is displaced in the approaching direction with respect to the outer cylinder 14 when a support load is input. In this case, the mounting direction of the mount is appropriately determined in accordance with the input direction of the supporting load. Specifically, in the engine mount 10 of the specific example described above, the support rubber elastic body 16 is positioned substantially below the inner cylinder fitting 12 in the mounted state, but the inner cylinder fitting 12 is moved toward the body side by the outer cylinder. When the metal fittings 14 are attached to the power unit, respectively, on the contrary, the support rubber elastic body 16 is mounted above the inner cylindrical metal fitting 12.

Further, the equilibrium chamber may be of any type as long as its volume change can be easily tolerated, and its structure is not limited at all.

Furthermore, the shape and structure of the orifice passage 66 are appropriately set in accordance with the anti-vibration characteristics required for the mount, and are not limited at all.

In addition, in the above-described embodiment, a specific example in which the present invention is applied to an automobile engine mount is shown. However, the present invention can be applied to various fluid-filled cylindrical mounts. There are, of course,
This is advantageously applied to a mount in which the supporting load is input in a direction shifted from the vibration input direction.

[0066]

As is apparent from the above description, any of the fluid-filled cylindrical mounts constructed according to the first to fifth aspects of the present invention has a structure in which the support rubber elastic body is axially intermediate. The elastic deformation characteristics in the direction perpendicular to the mount axis are set differently from each other in the portion and the axially opposite side portions. Even when the input direction of the vibration load and the input direction of the support load at the time of mounting are different, it is possible to achieve both an effective anti-vibration effect based on the flow action of the fluid and a good load support characteristic, and to achieve a high degree. It becomes.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an automobile engine mount as a specific example of an embodiment of the present invention, and corresponds to a II section in FIG.

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

FIG. 3 is a right side view in FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Engine mount 12 Inner cylinder fitting 14 Outer cylinder fitting 16 Support rubber elastic body 38 Pocket part 40 First circumferential side wall part 42 Second circumferential side wall part 44 Axial side wall part 50 Uneven thickness part 52 Slit 62 Pressure receiving chamber 64 Equilibrium chamber 66 Orifice passage

Claims (5)

[Claims] 1. A support rubber elastic body is interposed between a shaft member and an outer cylinder member spaced apart from the shaft member on one side of the shaft member which is positioned to sandwich the shaft member in a direction perpendicular to the shaft. By providing a slit that penetrates in the axial direction and expands in the circumferential direction on the other side, the shaft member and the outer cylindrical member are substantially connected only on the one side by the supporting rubber elastic body, while the shaft is Between the member and the outer cylindrical member, both side walls in the axial direction and the circumferential direction are formed of the supporting rubber elastic body, and a non-compressible fluid is sealed therein to form a pressure receiving chamber to which vibration is input. An equilibrium chamber in which an incompressible fluid is sealed and volume change is allowed is formed on the side of the slit forming portion between the shaft member and the outer cylinder member, and the pressure receiving chamber and the equilibrium chamber are mutually connected. An orifice passage communicating with the shaft member is provided. In the fluid-filled cylindrical mount attached to each one of the connected bodies to which the outer cylindrical member is vibration-isolated, the elastic deformation characteristics of the support rubber elastic body in a direction perpendicular to a mount axis are determined on both sides in a circumferential direction of the pressure receiving chamber. An axial intermediate portion forming a wall portion and an axial both side portion forming an axial side wall portion of the pressure receiving chamber are different from each other, and the pressure receiving chamber is formed at an axial intermediate portion of the supporting rubber elastic body. A fluid input characterized in that a load input direction in which a pressure change is easily applied to the load and a load input direction in which tensile deformation is unlikely to occur in both axial portions of the supporting rubber elastic body are circumferentially shifted from each other. Type cylindrical mount. 2. A vibration load to be damped is input in a load input direction in which a pressure change is likely to be applied to the pressure receiving chamber at an axially intermediate portion of the support rubber elastic body, while an axial direction of the support rubber elastic body is set. The fluid-filled cylindrical mount according to claim 1, wherein a supporting load acting between the connected members is input in a load input direction in which tensile deformation is hardly generated on both side portions. 3. A supporting rubber elastic body is interposed between the shaft member and an outer cylinder member spaced apart from the shaft member on one side of the shaft member which is sandwiched in a direction perpendicular to the shaft. By providing a slit that penetrates in the axial direction and expands in the circumferential direction on the other side, the shaft member and the outer cylindrical member are substantially connected only on the one side by the supporting rubber elastic body, while the shaft is Between the member and the outer cylindrical member, both side walls in the axial direction and the circumferential direction are formed of the supporting rubber elastic body, and a non-compressible fluid is sealed therein to form a pressure receiving chamber to which vibration is input. An equilibrium chamber in which an incompressible fluid is sealed and volume change is allowed is formed on the side of the slit forming portion between the shaft member and the outer cylinder member, and the pressure receiving chamber and the equilibrium chamber are mutually connected. An orifice passage communicating with the shaft member is provided. In the fluid-filled cylindrical mount attached to each one of the connected bodies to which the outer cylindrical member is vibration-isolated, the support rubber elastic body includes an axially intermediate portion that constitutes a circumferential side wall of the pressure receiving chamber. The load input direction in the direction perpendicular to the axis at which the compressive and shear stresses on both sides in the circumferential direction are substantially equal at the time of load input, and the load on the axial both side portions of the support rubber elastic body constituting the axial side walls of the pressure receiving chamber. By making the load input directions in the direction perpendicular to the axis in which the compressive and shear stresses on both sides in the circumferential direction are substantially equal at the time of input different from each other, the elastic deformation characteristics of the support rubber elastic body in the direction perpendicular to the mount axis can be calculated in the axial direction A fluid-filled cylindrical mount characterized in that the portion and the axial side portions are different from each other. 4. A support rubber elastic body is interposed between a shaft member and an outer cylindrical member spaced apart from the shaft member on one side of the shaft member which is sandwiched in a direction perpendicular to the shaft. By providing a slit that penetrates in the axial direction and expands in the circumferential direction on the other side, the shaft member and the outer cylindrical member are substantially connected only on the one side by the supporting rubber elastic body, while the shaft is Between the member and the outer cylindrical member, both side walls in the axial direction and the circumferential direction are formed of the supporting rubber elastic body, and a non-compressible fluid is sealed therein to form a pressure receiving chamber to which vibration is input. An equilibrium chamber in which an incompressible fluid is sealed and volume change is allowed is formed on the side of the slit forming portion between the shaft member and the outer cylinder member, and the pressure receiving chamber and the equilibrium chamber are mutually connected. An orifice passage communicating with the shaft member is provided. In the fluid-filled cylindrical mount attached to each one of the connected bodies to which the outer cylinder member is vibration-proof connected, the slit has a substantially constant cross-sectional shape over the entire length in the mount axial direction, and the support rubber elastic body is provided. Forming a depressed or protruding portion at a circumferentially intermediate portion between both end surfaces in the axial direction, and displacing a circumferential center of the deflected portion in a circumferential direction with respect to a circumferential center of the pressure receiving chamber. Thus, the elastic deformation characteristics of the supporting rubber elastic body in the direction perpendicular to the mount axis can be changed by changing the axially intermediate portions forming the circumferential side walls of the pressure receiving chamber and the axial directions forming the axial side walls of the pressure receiving chamber. A fluid-filled cylindrical mount characterized by being different from each other on both sides. 5. A vibration load to be damped, wherein an amount of deviation in a circumferential direction of a circumferential center of the pressure receiving chamber with respect to a circumferential center of the uneven thickness portion is applied between the shaft member and the outer cylinder member, respectively. 5. The fluid-filled cylindrical mount according to claim 4, wherein the fluid load type cylindrical mount is set in accordance with a shift amount of a support load acting between the connected bodies with respect to the input direction in the input direction.