JPH0434A - Fluid seal type cylindrical mount device - Google Patents

Abstract

PURPOSE:To prevent swelling deformation of a wall part of a main liquid chamber by forming a peripheral surface of an inner cylinder fitting, where wall parts of both sides in the mount shaft direction are fixed, among peripheral wall parts of the main liquid chamber made of the rubber elastic material into an inclined surface inclined toward the inside of the axial direction. CONSTITUTION:A power unit weight is given between inner and outer cylinder fittings 10, 12, to deform a rubber elastic member 14. The inner and outer cylinder fittings 10, 12 are thereby positioned concentrically in outline. But, since hard walls 23, 23 forming wall parts of both sides in the mount shaft direction of a pressure receiver chamber 54 are fixed on inclined surfaces 13, 13 inclined toward the inside of the axial direction in the inner cylinder fitting 10 side, a power unit weight given at the time of installation is given to each hard wall 23 as the component force (compressing force) vertical to the inclined surface 13 and the component force (shearing force) along the inclined surface. The bending moment for curving the hard walls 23 toward the inside thereby works against the hard walls 23 to generate the curve deformation projecting toward the inside.

Description

Detailed Description of the Invention (Technical Field) The present invention relates to a fluid-filled cylindrical mount device that obtains a vibration damping effect based on the flow action of a fluid sealed therein, and particularly relates to a fluid-filled cylindrical mount device that obtains a vibration damping effect based on the flow action of a fluid sealed therein. The present invention relates to a technique for improving the vibration-proofing performance of a mount by more effectively exhibiting the vibration-proofing effect due to the flow action.

(Background Art) Conventionally, vibration transmission systems have been interposed between members that constitute vibration transmission systems.
As a type of mounting device that connects these two components in a vibration-proof manner, an inner cylindrical metal fitting and an outer cylindrical metal fitting arranged at a predetermined distance from each other in the radial direction are integrated using a rubber elastic body interposed between them. A so-called cylindrical mount device is known that has a structure in which the cylindrical metal fittings are connected to each other, and is designed to mainly dampen radial vibration input between the inner and outer cylindrical metal fittings. Since such a cylindrical mount device can advantageously restrict the relative displacement of the inner and outer cylindrical metal fittings when a large vibration load is input, it can be used, for example, in automobile engine mounts, differential mounts, suspension boots, etc. As Shu et al.
It has been suitably used.

In addition, in recent years, Japanese Patent Publication No. 4B-36151, Japanese Patent Application Publication No. 62-196434, Japanese Patent Application Publication No. 63-28934
In Publication No. 9 and U.S. Patent No. 4,690,389, etc., a peripheral wall portion is formed of the rubber elastic body between the inner cylinder metal fitting and the outer cylinder metal fitting in such a cylindrical mount device. A main liquid chamber in which an internal pressure fluctuation is generated based on the deformation of the rubber elastic body, and a sub-liquid chamber in which a relative internal pressure difference is generated between the main liquid chamber and the main liquid chamber when vibration is input are formed. A so-called fluid-filled cylindrical type having a structure in which a predetermined incompressible fluid is sealed inside a liquid chamber and a sub-liquid chamber, and an orifice passage is provided to communicate the main liquid chamber and sub-liquid chamber with each other. Various mounting devices have been proposed.

In other words, in such a fluid-filled cylindrical mount device, the internal pressure difference generated between the main liquid chamber and the sub-liquid chamber during vibration input causes the fluid to flow between the two liquid chambers through the orifice passage. is generated, and a predetermined vibration damping effect is exerted based on the resonance effect of the fluid flowing through the orifice passage.

However, in such a fluid-filled cylindrical mount device, due to the liquid pressure induced in the main liquid chamber when vibration is input,
The walls on both sides of the main liquid chamber in the mount axis direction tend to bulge and deform outward in the mount axis direction, and such bulging deformation of the walls leads to an increase in the volume of the main liquid chamber. There was a risk that the amount of change in internal pressure within the liquid chamber would decrease, making it impossible to ensure a sufficient amount of fluid flowing through the orifice passage, making it impossible to obtain the desired vibration damping effect.

In addition, such bulging deformation of the wall of the main liquid chamber is more likely to occur as the wall thickness of the main liquid chamber becomes thinner, so it is difficult to make the rubber elastic body thinner. It also had the problem that it was difficult to set it softly.

(Problem to be solved) Here, the present invention has been made against the background of the above-mentioned circumstances, and the problem to be solved is:
We have revealed a technology that can advantageously prevent the bulging deformation of the main liquid chamber wall without increasing its wall thickness, and thereby effectively ensure the amount of fluid that can flow through the orifice passage. An object of the present invention is to provide a fluid-filled cylindrical mount device that can exhibit excellent vibration damping effects.

(Solution Means) In order to solve this problem, the present invention includes an inner cylindrical metal fitting and an outer cylindrical metal fitting that are arranged at a predetermined distance in the radial direction, and a cylindrical metal fitting that is interposed between them. By connecting the inner cylindrical metal fitting and the outer cylindrical metal fitting with a rubber elastic body, and by forming a peripheral wall portion of the rubber elastic body, the inner cylindrical metal fitting and the outer cylindrical metal fitting are connected by a rubber elastic body. A main liquid chamber in which internal pressure fluctuations are generated and a sub-liquid chamber in which a relative internal pressure difference is generated between the main liquid chamber and the main liquid chamber when vibration is input are formed, and the inside of the main liquid chamber and the sub-liquid chamber are In a fluid-filled cylindrical mount device that encloses a predetermined incompressible fluid and is provided with an orifice passage that allows the main liquid chamber and the sub-liquid chamber to communicate with each other, the main liquid chamber is made of a rubber elastic body. Among the peripheral walls of the liquid chamber, the outer peripheral surfaces of the inner cylinder fitting to which the walls on both sides in the axial direction of the mount are fixed are each formed into an inclined surface that slopes inward in the axial direction. It is something.

(Example) Hereinafter, in order to clarify the present invention more specifically, an example of the present invention will be described in detail with reference to the drawings.

First, FIGS. 1 and 2 show a specific example of the invention applied to an automobile engine mount. In these figures, reference numerals 10 and 12 denote an inner cylindrical metal fitting and an outer cylindrical metal fitting, which are arranged eccentrically by a predetermined distance in the radial direction, and a rubber elastic body 14 interposed between them allows They are elastically connected to each other. In this engine mount, the inner cylindrical metal fitting 10 and the outer cylindrical metal fitting 12 are attached to either the vehicle body side or the power unit side including the engine, so that the power unit is supported with vibration isolation against the vehicle body. In addition, under such wearing conditions,
The weight of the power unit is applied as an initial load (static load) in the eccentric direction of both metal fittings 10.12, and the rubber elastic body 14 is elastically deformed, so that both metal fittings 10.12 are approximately concentric. (See Figure 10). In addition, under such mounting conditions, the engine mount is subjected to vibrations that are mainly aimed at vibration isolation in the eccentric direction (in the vertical direction in FIG. 10) between the inner cylinder metal fitting 10 and the outer cylinder metal fitting 12. You will be prompted to enter the information.

More specifically, as shown in FIGS. 3 and 4, the inner cylindrical fitting 10 is formed in a thick-walled cylindrical shape as a whole, and has axially opposite sides on its outer peripheral surface. A pair of arcuate protrusions 11.11 are integrally provided. Each of these arcuate protrusions 11.11 has a substantially triangular cross-sectional shape and is formed to extend approximately half a circumference in the circumferential direction. Inclined surfaces 13 each of which is inclined inward in the axial direction of the inner cylindrical fitting 10
．． It is said to be 13.

Further, on the radially outer side of the inner cylindrical fitting 10, a metal sleeve 16 having a substantially thin-walled cylindrical shape as a whole is arranged radially at a predetermined distance and eccentrically by a predetermined dimension.

As shown in FIG. 5, the rubber elastic body 1
4 is interposed therebetween, and is formed as an integral vulcanized molded product 18 which is vulcanized and bonded to the outer circumferential surface of the inner cylindrical fitting 10 and the inner circumferential surface of the metal sleeve 16, respectively.

In addition, this integrally vulcanized molded product 18 has a groove extending approximately half a circumference in the circumferential direction along the inner circumferential surface of the metal sleeve 16 on the side where the distance between the inner cylinder fitting 10 and the metal sleeve 16 in the eccentric direction is smaller. A cavity 20 is formed which extends in the axial direction and has a generally arcuate cross section. As a result, the rubber elastic body 14 substantially elastically connects the inner cylindrical fitting IO and the outer cylindrical fitting 12 only on the side where the distance between them in the eccentric direction is large. In this way, the tensile stress generated when the rubber elastic body 14 is deformed due to the load weight of the power unit applied in the mounted state as described above can be reduced as much as possible. It has become.

Further, the rubber elastic body 14 is provided with a window 24 provided in the metal sleeve 16 at a position radially opposite to the cavity 20 with the inner cylinder fitting 10 interposed therebetween. A pocket portion 22 is formed in the form of an open recess. Here, the pocket portion 22
In this case, the peripheral wall portion is made of the rubber elastic body 14, and 1. Moreover, the vertical walls 23 and 23 constituting the wall portions on both sides in the axial direction of the peripheral wall portion are respectively connected to the inner cylinder fitting 1.
0 side, it is fixed to the inclined surface 13 of the circular arc-shaped protrusion 11 and is positioned so as to extend outward in the radial direction from above the inclined surface 13.

On the other hand, the metal sleeve 16 has a diameter reduced over a predetermined width at its axial center portion to form a small diameter portion 26 . In particular, a portion of the small diameter portion 26 located on the side where the distance between the inner cylinder fitting 10 and the metal sleeve 16 in the eccentric direction is smaller is further recessed inward in the radial direction, so that the space 20 By being inserted into the interior, a recess 28 opening to the outer peripheral surface is formed therein, and a recess 28 is formed in the circumferential direction with the small diameter portion 26 as the bottom so as to connect both ends of the recess 28 in the circumferential direction. An extending circumferential groove 30 is formed.

Furthermore, the integrally vulcanized molded product 18 having such a structure has a curved shape that approximately corresponds to the shape of the inner circumferential surface of the cavity 20, which is separately formed from a rubber material on the inside of the cavity 20. A stopper rubber 32 having a plate shape is inserted from one side in the axial direction and is arranged at an annular mounting portion 34 integrally provided at one end in the longitudinal direction.

The inner cylindrical metal fitting 10 side is supported by being fitted and fixed to the axial end of the inner cylindrical fitting 10 and bonded as necessary. When the mount is attached, the stopper rubber 32 is positioned facing the small-diameter portion 26 of the metal sleeve 16 at a predetermined distance in the vibration input direction (see FIG. 10), so that the stopper rubber 32 rubber 32
By contacting the small diameter portion 26 of the metal sleeve 16 at , the amount of relative displacement between the inner cylindrical fitting 10 and the outer cylindrical fitting 12 in the rebound direction can be regulated to a predetermined amount.

Further, in the integrally vulcanized molded product 18, inside the circumferential groove 30 of the metal sleeve 16, first and second orifice fittings 40 and 42 each having a substantially semicylindrical shape are provided as inner cylindrical fittings. 10 and the metal sleeve 16 are fitted from both sides in the eccentric direction and assembled into a cylindrical shape,
Further, the outer cylindrical metal fitting 12 is fitted and fixed onto the outer circumferential surface of the outer cylindrical member.

As shown in FIGS. 6 and 7, the first orifice fitting 40 has an outer circumferential surface that expands in a spiral shape from approximately the center, and an inner end thereof is connected to the communication hole 4.
4, the groove 4 is opened toward the inner circumferential surface side, and the outer end thereof is opened toward the circumferential end side.
6.

On the other hand, in the second orifice fitting 42, the eighth
As shown in FIG. 9 and FIG. 9, notches 48, 48 are provided at both ends in the circumferential direction, and a notch window 50, 50 is provided in the central portion.
Further, a diaphragm 52 as a flexible membrane that is easily elastically deformable is integrally bonded by vulcanization so as to close the cutout windows 50 and 50 from the inside.

The opening of the pocket portion 22 provided in the integrally vulcanized molded product 18 is covered by the first orifice fitting 40, so that the peripheral wall portion inside the pocket portion 22 is made of rubber elastic material. It is composed of a body 14, and when vibration is applied manually between the inner and outer cylindrical fittings 10 and 12,
A pressure receiving chamber 54 is formed as a main liquid chamber in which internal pressure fluctuations are induced based on the elastic deformation of the rubber elastic body 14.

On the other hand, the opening of the recess 28 provided in the integrally vulcanized molded product 18 is covered by the second orifice fitting 42, so that the elasticity of the diaphragm 52 is contained inside the recess 28. An equilibrium chamber 56 is formed as a sub-liquid chamber whose volume is allowed to change based on deformation.

Note that between the diaphragm 52 that defines the equilibrium chamber 56 and the outer cylindrical fitting 12, the diaphragm 5
A space 58 is formed that allows the deformation of 2, and
These spaces 58 and 58 are communicated with the external space through through holes 60 provided in the outer cylindrical fitting 12, respectively.

Further, a thin sealing rubber layer 66 is integrally provided on the inner peripheral surface of the outer cylindrical fitting 12 over substantially the entire surface, and the outer cylindrical fitting 12 is fitted onto the metal sleeve 16. As a result, the sealing rubber layer 66 is compressed between the fitting surfaces of the outer cylindrical fitting 12 and the metal sleeve 16, thereby liquid-tightly sealing the insides of the pressure receiving chamber 54 and the equilibrium chamber 56. These pressure receiving chambers 54 and equilibrium chambers 56
A predetermined incompressible fluid such as water, alkylene glycol, polyalkylene glycol, silicone oil, etc. is sealed inside each of them.

Furthermore, by fitting the outer cylinder fitting 12 onto the metal sleeve 16, the concave groove 46 of the first orifice fitting 40 and the notch 4 of the second orifice fitting 42 are formed.
The openings on the outer peripheral surface side in 8 are each covered,
Pass it through the notch 48 into the groove 46,
An orifice passage 62 is formed that allows the pressure receiving chamber 54 and the equilibrium chamber 56 to communicate with each other and allows fluid to flow between the two chambers 54 and 56. In this embodiment, the orifice passage 62 is formed with a long flow path extending in a spiral shape, so that shaking and bouncing are prevented based on the resonance effect of the fluid flowing inside the orifice passage 62. It is tuned so that it can exhibit an excellent damping effect against low-frequency vibrations equivalent to the above.

Further, the inside of the pressure receiving chamber 54 is formed of a hard material having an outer circumferential surface shape that approximately corresponds to the inner circumferential surface shape of the pressure receiving chamber 54 and that is smaller in circumference than the inner circumferential surface of the pressure receiving chamber 54. A movable block 64 is housed so as to be freely movable. By arranging this movable block 64, the inside of the pressure receiving chamber 54 is narrowed, so that around the movable block 64, based on the deformation of the rubber elastic body 14 and the displacement of the movable block 64 at the time of vibration input, This creates a flow of fluid. In addition, in this embodiment, an excellent vibration insulation effect can be exhibited against high frequency vibrations such as engine vibrations based on the resonance effect of the fluid that is caused to flow through the constricted portion formed in the pressure receiving chamber 54. Thus, the size of the narrowed portion formed within the pressure receiving chamber 54, in other words, the shape of the movable block 64, is tuned.

In the engine mount having such a structure, as described above, the inner tube fitting 10 is attached to the power unit side, and the outer tube fitting 12 is attached to the vehicle body side, so that the vehicle body and the power unit are connected. It is interposed between the
When vibration is input between the inner cylindrical metal fitting 10 and the outer cylindrical metal fitting 12, an internal pressure fluctuation is induced in the pressure receiving chamber 54 due to the deformation of the rubber elastic body 14, and the pressure receiving chamber 54 and the equilibrium chamber 56 are A fluid flow is generated through the orifice passage 62 between them, and a damping effect on low frequency vibrations is exerted based on the resonance effect of the fluid flowing through the orifice passage 62. .

By the way, when installing such an engine mount, as shown in FIG.
．． As the power unit weight is applied between the parts 10 and 12 and the rubber elastic body 14 is deformed, the inner and outer cylindrical fittings 10 and 12 are positioned approximately concentrically. Specifically, the vertical walls 23.23 that constitute the walls on both sides of the mount in the pressure receiving chamber 54 in the axial direction are fixed on the inclined surfaces 13.13 that are inclined inward in the axial direction on the inner cylinder fitting 10 side. Therefore, the weight of the power unit exerted on each vertical wall 23 during such installation is a component force perpendicular to the inclined surface 13 (compressive force) and a component force along the inclined surface (shearing force).
As a result, a bending moment that causes the vertical wall 23 to curve inward acts on the vertical wall 23, thereby causing an inwardly convex curved deformation to the vertical wall 23. .

Under such mounting conditions, when vibration is input to the engine mount, when the inner and outer cylindrical fittings 10.12 are displaced in the direction toward each other, the vertical wall 23.
Since the deformation at 23 is caused to protrude into the pressure receiving chamber 54, internal pressure fluctuations within the pressure receiving chamber 54 are more effectively produced.
As a result, the amount of fluid flowing through the orifice passage 62 can be advantageously ensured, and the vibration damping effect based on the resonance effect of the fluid can be exhibited even more effectively.

Note that the angle of inclination of the inclined surface 13 formed by the arcuate protrusion 11 of the inner cylinder fitting 10 is not particularly limited, but as described above, when the weight of the power unit is applied and when a vibration load is input, , will normally be set at 20 to 30 degrees so that a bending moment for inwardly curving can be effectively applied to the vertical walls 23, 23.

Moreover, in the engine mount in this example,
Since a movable block 64 is housed in the pressure receiving chamber 54 and a fluid flow path is formed around the movable block 64, based on the resonance effect of the fluid flowing through the fluid flow path, It is possible to achieve a low spring movement effect of the mount when vibrations in a high frequency range are input, and thereby to effectively exhibit a vibration insulating effect against such high frequency vibrations.

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

For example, the specific structure for forming the inclined surface on the inner cylindrical fitting is by no means limited to that of the above embodiment, and as illustrated, the protrusion having the inclined surface is integrally formed with the inner circumferential fitting. In addition to forming such a protrusion, a separate member constituting such a protrusion may be press-fitted, welded, or otherwise fixed to the inner cylindrical metal fitting to form an inclined surface, or a recess carved into the inner cylindrical metal fitting may be formed. It is also possible to form an inclined surface by the inner surface of the groove.

Further, in the above embodiment, when the power unit is mounted, the weight (initial load) of the power unit is applied, and the walls (23, 23) on both sides in the axial direction of the mount defining the main liquid chamber (54) are damaged. Although the slanted surface (13, 13,
13), the deformation of the wall portions (23, 23) upon vibration input can be advantageously caused by causing the wall portions (23, 23) to curve convexly toward the main liquid chamber side.
The present invention can also be advantageously applied to mounting devices to which such an initial load is not applied, such as suspension bushes for automobiles, and thereby the effects of the present invention can be effectively enjoyed. .

Furthermore, in the embodiment described above, a part of the wall is constituted by the diaphragm 52, and an equilibrium chamber 56 whose volume is allowed to change is formed.
The sub-liquid chamber was constructed in
As shown in Publication No. 6151, etc., both the main liquid chamber and the sub-liquid chamber have a pressure receiving chamber structure in which the peripheral wall is made of a rubber elastic body and internal pressure fluctuations are caused when vibration is input. In such a case, the outer circumferential surface of the inner cylindrical fitting to which the walls on both sides in the axial direction of the mount that define the sub-liquid chamber are fixed may also be formed with an inclination that slopes inward in the axial direction. It may also be configured as a surface.

In addition, the specific structure of the orifice passage that allows the main liquid chamber and the sub-liquid chamber to communicate with each other and allows fluid to flow between the two liquid chambers is determined by the vibration-proofing characteristics required for the mount device. It should be determined as appropriate depending on the situation, and is not limited in any way.

In addition, in the above embodiment, a specific example of the application of the present invention to an automobile engine mount was shown, but the present invention is also applicable to automobile differential mounts, podium mounts, suspension bushes, etc., or automobile engine mounts. Of course, the present invention can also be effectively applied to mounts in various other devices.

In addition, although not listed, the present invention can be implemented in embodiments with various changes, modifications, improvements, etc. based on the knowledge of those skilled in the art, and such embodiments include: It goes without saying that any of these methods are included within the scope of the present invention as long as they do not depart from the gist of the present invention.

(Effects of the Invention) As is clear from the above description, in the fluid-filled cylindrical mount device structured according to the present invention, the walls on both sides of the main liquid chamber in the axial direction of the mount are susceptible to vibration loads. At times, the main liquid chamber is curved so as to convex inward in the axial direction, and bulging deformation outward in the axial direction is prevented as much as possible, so internal pressure fluctuations in the main liquid chamber during vibration input are reduced. As a result, the amount of fluid flowing through the orifice passage can be advantageously maintained, and the vibration damping effect exerted by the flow of the fluid can be extremely effectively enjoyed. It is.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view showing a specific example of the present invention applied to an automobile engine mount, and FIG. 2 is a cross-sectional view taken along the line -■ in FIG. Moreover, FIG. 3 is a front view showing the inner cylinder metal fitting that constitutes the engine mount shown in FIG. 1, and FIG. 4 is a side view in FIG. 3. Furthermore, FIG. 5 is a longitudinal sectional view showing an integrally vulcanized molded product constituting the engine mount shown in FIG. 1. 6 is a sectional view showing a first orifice fitting that constitutes the engine mount shown in FIG. 1, and FIG. 7 is a plan view in FIG. 6. Furthermore, FIG. 8 is a cross-sectional view showing a second orifice fitting that constitutes the engine mount shown in FIG. 1, and FIG. 9 is a bottom view in FIG. 8. Moreover, FIG. 10 is a longitudinal cross-sectional view corresponding to FIG. 1, showing a state in which the engine mount shown in FIG. 1 is attached to a vehicle.

Claims (1)

[Claims] An inner cylindrical metal fitting and an outer cylindrical metal fitting arranged at a predetermined distance in the radial direction are connected by a rubber elastic body interposed between them, and the inner cylindrical metal fitting and the outer cylindrical metal fitting are connected by a rubber elastic body interposed between them. There is a main liquid chamber between the outer cylindrical fitting and the main liquid chamber, whose peripheral wall is made of the rubber elastic body, which causes internal pressure fluctuations based on the deformation of the rubber elastic body when vibration is input; A sub-liquid chamber is formed in which a relative internal pressure difference is created between the main liquid chamber and the sub-liquid chamber, and a predetermined incompressible fluid is sealed inside the main liquid chamber and the sub-liquid chamber, and In the fluid-filled cylindrical mount device, which is provided with an orifice passage that allows communication between the main liquid chamber and the auxiliary liquid chamber, the wall portions on both sides in the axial direction of the mount among the peripheral wall portions of the main liquid chamber made of the rubber elastic body. A fluid-filled cylindrical mount device characterized in that the outer circumferential surfaces of the inner cylindrical fittings to which the inner cylindrical fittings are fixed are each formed into inclined surfaces that slope axially inward.