JP2002327787A - Vibrationproof device sealed with fluid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To compact an axial dimension to simplify the structure in the fluid sealed vibrationproof device in which a support shaft formed in a first fitting member is inserted from one axial opening at a cylindrical part formed in a second fitting member to arrange it and the cylindrical part and the support shaft are connected elastically by an elastic rubber body. SOLUTION: An axial liquid chamber 80 which can generate variation of pressure as an axial vibration is input, is formed between the elastic rubber body 16 and the bottom wall 50 of the second fitting 14, and a pair of liquid chambers 82, 82 orthogonal to the axis oppositely positioning in the radial direction inside of the elastic rubber body and generating relative pressure variation orthogonal to the axis as an axial vibration is input, are formed. And further, a first orifice passage 86 through which these pairs of liquid chambers 82, 82 are forced to communicate with the axial liquid chamber 80 and second orifice passages 84, 84 connecting these pairs of liquid chambers 82, 82 to communicate with each other are formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid-filled type vibration damping device which obtains a vibration damping effect based on a flow action of an incompressible fluid sealed therein, and more particularly to a fluid-filled vibration damping device in a central axis direction and a direction perpendicular to the axis. The present invention relates to a fluid-filled type vibration damping device that exhibits an effective vibration damping effect based on the flow action of an incompressible fluid with respect to input vibration in any direction, and can be suitably used for, for example, an engine mount for an automobile. .

[0002]

2. Description of the Related Art Conventionally, as one type of a vibration isolating device as a vibration isolating connection member or a vibration isolating support member interposed between members constituting a vibration transmission system, resonance of an incompressible fluid enclosed therein has been performed. 2. Description of the Related Art There is known a fluid-filled type vibration damping device in which a vibration damping effect is obtained based on a flow action such as an action.
Japanese Patent Application Laid-Open No. 2244 discloses a fluid-filled type vibration damping device capable of exhibiting a vibration damping effect based on the flow action of an incompressible fluid with respect to both input vibrations in a central axis direction and a direction perpendicular to the axis. ing.

[0003] In such a fluid-filled type vibration damping device, the first mounting bracket is arranged to extend in the axial direction by being inserted from one axial side of the cylindrical portion formed in the second mounting bracket. The first mounting bracket and the second mounting bracket are elastically connected to each other in the direction perpendicular to the axis by the main rubber elastic body, so that one opening in the axial direction of the cylindrical portion is fluid-tight with the main rubber elastic body. And the other opening in the axial direction of the cylindrical portion is closed with a flexible rubber film, and a rubber elastic body is provided on both sides of the partition member fixedly supported by the second mounting member. A pressure receiving chamber in which a part of a wall is formed and vibration is input;
A part of the wall is formed by the flexible rubber film to form an equilibrium chamber in which a volume change is allowed. Further, the pressure receiving chamber and the equilibrium chamber communicate with each other through the first orifice passage, while the main rubber elasticity is formed. A pair of working fluid chambers are provided inside the body on both sides of the first mounting bracket in a direction perpendicular to the axis, and the pair of working fluid chambers are connected to each other by a second orifice passage. When an axial vibration is input between the first mounting bracket and the second mounting bracket, the vibration is prevented based on the resonance action of the fluid caused to flow through the first orifice passage between the pressure receiving chamber and the equilibrium chamber. In addition to exerting the vibration effect, when the vibration perpendicular to the axis is input between the first mounting bracket and the second mounting bracket, the resonance action of the fluid caused to flow through the second orifice passage between the pair of working fluid chambers Anti-vibration effect based on And it is able to exert.

[0004] Such a fluid-filled type vibration damping device is employed, for example, in an engine mount for a horizontal engine in an FF (Front Engine / Front Drive) type vehicle, and fixes the first mounting bracket to the power unit.
The second mounting bracket is fixed to the body, the pair of working fluid chambers is disposed in the vehicle front-rear direction, and the power unit is supported on the body by vibration isolation. It is possible to obtain a vibration damping effect based on the resonance action of the fluid for each of the vibrations.

However, in the fluid filled type vibration damping device having the conventional structure as described above, a rubber elastic body forming a pair of working liquid chambers, a pressure receiving chamber, and a balance are arranged in the central axis direction of the second mounting member. Since the chambers are positioned in series with each other, it is inevitable that the size of the entire device will increase in the axial direction of the vibration isolator, and the installation space is particularly limited, such as in engine mounts for automobiles. When it was done, the problem was that it was difficult to deal with it.

Further, in the fluid filled type vibration damping device having such a conventional structure, the first orifice passage for connecting the pressure receiving chamber and the equilibrium chamber is formed by assembling two independently formed orifice members, and a pair of orifice members. Since the second orifice passages for interconnecting the working fluid chambers need to be formed independently of each other, there is also a problem that the number of parts is large, the structure is complicated, and the production is troublesome.

Furthermore, when such a fluid-filled type vibration damping device having a conventional structure is applied to, for example, an engine mount for an FF type vehicle of a horizontal engine, the center axes of the first and second mounting brackets are generally fixed. The power unit is fixed to a protruding tip portion of the first mounting bracket, which is disposed so as to extend in a substantially vertical direction and protrudes from an axially upper opening of the second mounting bracket, while the second mounting bracket is provided. Since the lower end in the axial direction is fixed to the vehicle body,
As the size of the vibration isolator increases in the axial direction, the moment applied to the portion where the second mounting member is fixed to the body by the load input in the direction perpendicular to the axis increases, and the member strength and the mounting strength at the fixing portion , Durability and the like may be a problem.

[0008]

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a fluid that can be applied to both input vibrations in the axial direction and in the direction perpendicular to the axial direction. A fluid-filled type vibration damping device having a novel structure that is simple in structure and easy to manufacture, is capable of effectively exhibiting the vibration damping effect based on the flow action of the fluid, and can be designed to have a small size in the central axis direction. Is to do.

[0009]

An embodiment of the present invention which has been made to solve such a problem will be described below. The components employed in each of the embodiments described below can be employed in any combination as possible. In addition, aspects or technical features of the present invention are not limited to those described below, but are described in the entire specification and drawings, or based on the invention ideas that can be understood by those skilled in the art from the descriptions. It should be understood that it is recognized on the basis of.

That is, the features of the present invention are as follows:
(A) a first mounting member having a rod-shaped support shaft;
(B) having a cup shape, the first mounting member is spaced apart from the opening side, and the support shaft of the first mounting member is axially inserted from the opening to be positioned; A second mounting member, and (c) a step portion is provided at an intermediate portion in the axial direction, a small-diameter portion and a large-diameter portion are formed sandwiching the step portion in the axial direction. A metal sleeve provided with a pair of windows facing each other in one direction, and spaced apart on the outer peripheral side of a support shaft of the first mounting member; and (d) a support shaft of the first mounting member. And the metal sleeve is disposed between the radially opposed surfaces of the metal sleeve and vulcanized and bonded to the support shaft and the metal sleeve.
A main body rubber elastic body having a pair of pockets formed at a position facing each other in a direction perpendicular to the axis with the support shaft of the first mounting member interposed therebetween and opening to an outer peripheral surface through a pair of windows in the metal sleeve; e) the metal sleeve is inserted into and fixed to the cylindrical wall portion of the second mounting member, and the opening of the second mounting member is closed in a fluid-tight manner by the main body rubber elastic body. A part of the wall is formed of a rubber elastic body, and is formed between the axial end of the support shaft of the first mounting member and the bottom wall of the second mounting member. And (f) the pair of windows in the metal sleeve are fluid-tightly closed by the cylindrical wall of the second mounting member. By this, the first mounting portion is provided inside the main rubber elastic body. A pair of right-axis liquid chambers formed so as to face each other in the direction perpendicular to the axis with the support shaft portion interposed therebetween, and pressure fluctuations caused by input of a vibration load in the direction perpendicular to the axis; And (h) a tubular portion, and an annular portion that extends radially inward from one axial end of the tubular portion. The cylindrical portion is externally fitted to the small-diameter portion of the metal sleeve and is sandwiched between the small-diameter portion and the cylindrical portion of the second mounting member, and the annular portion is formed of the metal sleeve. An orifice member fixedly attached to the metal sleeve and the second mounting member by being sandwiched between the axial end of the small diameter portion and the bottom wall of the second mounting member, (I) the axial liquid chamber formed by the orifice member and A first orifice passage occupied passed, communicating respectively perpendicular liquid chamber,
(J) A fluid-filled vibration isolator having a second orifice passage formed by the orifice member and communicating the pair of liquid chambers in a direction perpendicular to the axis.

In such a fluid-filled type vibration damping device having a structure according to the present invention, when an axial vibration is input,
Pressure fluctuation is caused in the axial liquid chamber along with the elastic deformation of the main rubber elastic body, so that relative pressure fluctuation is generated between the axial liquid chamber and the pair of liquid chambers perpendicular to the axis, Fluid flow through the first orifice passage is generated, and an effective vibration damping effect can be exhibited based on the flow action of the fluid caused to flow through the first orifice passage. On the other hand, at the time of vibration input in the direction perpendicular to the axis, relative pressure fluctuation occurs between the pair of liquid chambers in the direction perpendicular to the axis along with the elastic deformation of the main rubber elastic body, and the fluid flowing through the second orifice passage is changed. The flow is generated, and an effective vibration damping effect can be exhibited based on the flow action of the fluid caused to flow through the second orifice passage.

In the fluid filled type vibration damping device, a pair of liquid chambers in a direction perpendicular to the axis are used, which are formed inside the elastic body of the main body and cause relative pressure fluctuation when vibration is input in the direction perpendicular to the axis. Then, the relative pressure fluctuation between the axial liquid chamber and the axial liquid chamber is generated at the time of the axial vibration input. There is no need to separately and independently form an equilibrium chamber in which pressure fluctuations are generated, and the number of liquid chambers as a whole can be reduced as compared with the fluid-filled vibration isolator of the conventional structure as described above. As a result, the axial size of the entire vibration isolator can be set small.

In addition, a first orifice passage for permitting fluid flow between the axial liquid chamber and the liquid chamber perpendicular to the axis at the time of vibration input in the axial direction, and a pair of fluids at right angles to the axis at the time of vibration input in the axis perpendicular direction. Since each of the second orifice passages permitting fluid flow between the chambers is formed by a single orifice member, the number of parts and the number of assembling steps are reduced, so that the manufacturing becomes easier and the manufacturing becomes easier. Costs can also be reduced.

Further, in the present invention, the small-diameter portion of the metal sleeve is formed to have an axial length extending to the window forming portion, and the cylindrical portion of the orifice member externally inserted into the small-diameter portion. Is preferably extended to the pair of liquid chambers in a direction perpendicular to the axis. By adopting such a configuration, a large area for forming the orifice passage in the orifice member can be ensured, and the degree of freedom in designing the length and cross-sectional area of the orifice passage can be improved.

Further, in the present invention, in the pair of working liquid chambers, the expansion spring constant of the elastic wall portion on the axially outer side may be smaller than the expansion spring constant of the elastic wall portion on the axially inner side. desirable. By adopting such a configuration, when the vibration in the axial direction is input, the relief of the direct pressure fluctuation from the axial liquid chamber to the liquid chamber perpendicular to the axis due to the elastic deformation of the elastic wall portion in the axial direction can be prevented. This can be reduced or avoided, and the fluid flow rate through the first orifice passage can be advantageously secured, so that the vibration damping effect based on the fluid flow action against the input vibration in the axial direction can be more advantageously exhibited. It can be done.

Further, in the present invention, a through hole is formed in a bottom wall portion of the second mounting member which constitutes a part of a wall portion of the axial liquid chamber, and the through hole is formed by a movable rubber plate. A fluid-tight cover arrangement may be advantageously employed. With such a configuration, when inputting axial vibration in a frequency range higher than the tuning frequency of the first orifice passage,
Even if the flow resistance of the first orifice passage increases due to an anti-resonance effect or the like, the pressure fluctuation in the axial liquid chamber can be absorbed and reduced based on the elastic deformation of the movable rubber plate. Significant reduction in vibration isolation performance due to a large increase in the dynamic spring constant can be avoided.

[0017]

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

First, FIGS. 1 and 2 show an automobile engine mount 10 as one embodiment of the present invention. In this engine mount 10, a first mounting member 12 as a first mounting member and a second mounting member 14 as a second mounting member are spaced apart from each other. The second mounting member 14 has a structure in which the first mounting member 12 is mounted on a power unit of the vehicle, while the second mounting member 14 is mounted on a body of the vehicle. As a result, the power unit is supported on the body with vibration isolation. Note that the engine mount 10 of the present embodiment is mounted with the up-down direction in FIG. 1 being substantially vertical up-down direction. In the following description, the up-down direction refers to the up-down direction in FIG. Direction.

More specifically, the first mounting member 12 includes a support shaft portion 20 having a solid small diameter circular rod shape, and is provided at the upper end in the axial direction of the support shaft portion extending straight in the vertical direction. On the other hand, a mounting fixing portion 22 that extends in a thick flat shape on the central axis is integrally formed. Note that a tapered portion 24 is provided at an intermediate portion in the axial direction of the support shaft portion 20.
With the tapered portion 24 interposed therebetween, a lower portion in the axial direction of the support shaft portion 20 is a small-diameter portion 26, and an upper portion in the axial direction of the support shaft portion 20 is a large-diameter portion 28.

On the outer peripheral side of the first mounting bracket 12,
A metal sleeve 30 having a thin, large-diameter cylindrical shape is disposed on the same central axis at a predetermined distance in the radial direction. The metal sleeve 30 has a stepped cylindrical shape in which a step 31 is formed at a position slightly deviated from the center in the axial direction, and the upper side in the axial direction with the step 31 interposed therebetween has a large diameter. In addition to the portion 32, the lower side in the axial direction is a small diameter portion 33. Further, a pair of windows 34, 34 is formed in the axially intermediate portion of the metal sleeve 30 at portions opposed to each other in one direction in the radial direction.
Each of them is opened in the circumferential direction with a width in the axial direction reaching the step portion 31 with a length of less than half a circumference.

The first mounting member 12 is provided so as to be inserted from the axially upper opening of the metal sleeve 30, and the small-diameter portion 26 of the support shaft portion 20 of the first mounting member 12 is provided. The metal sleeve 30 is positioned so as to surround the entire body radially outwardly. In addition,
The mounting fixing part 22 of the first mounting bracket 12 is positioned so as to protrude axially upward from the metal sleeve 30, while the lower end of the supporting shaft part 20 in the axial direction is
Is located at an axially intermediate portion that does not reach the axially lower end.

Further, a main rubber elastic body 16 is disposed between the support shaft portion 20 of the first mounting member 12 and the radially opposed surfaces of the metal sleeve 30.
2 and the metal sleeve 30 are elastically connected. The main rubber elastic body 30 has a thick cylindrical shape as a whole, and its inner peripheral surface is vulcanized and adhered to the outer peripheral surface of the support shaft portion 20 of the first mounting bracket 12. The outer peripheral surface is vulcanized and bonded to the inner peripheral surface of the metal sleeve 30. In short, the main rubber elastic body 16 is formed as an integrally vulcanized molded product including the first mounting member 12 and the metal sleeve 30.

The main rubber elastic body 16 has a large-diameter circular recess 40 that opens downward at the lower end face in the axial direction.
Are formed, and a pair of pockets 42, 42 opening to the outer peripheral surface are formed on both sides of the first mounting bracket 12 in one radial direction. Each of the pair of pockets 42 has an expanded shape in which the axial opening width gradually increases as approaching the opening (see FIG. 1).
And a pair of windows 3 formed in the metal sleeve 30 and having a length of less than half a circumference in the circumferential direction (see FIG. 2).
4, 34, it is opened to the outer peripheral surface.

Here, a pair of pockets 42, 4
Each of the pockets 42 is formed so as to be deviated by a predetermined amount from the axial center of the main rubber elastic body 16 in the axial direction upward, and thereby each pocket portion 42 formed by the main rubber elastic body 16 is formed. The axial upper wall portion 44 and the axial lower wall portion 46 have different thicknesses, and the axial lower wall portion 46 is made thicker overall than the axial upper wall portion 44. I have. Accordingly, the axial lower wall portion has a larger axial and radial spring constant than the axial upper wall portion 44, and has an expanded spring constant or a wall spring constant in a bulging direction. The spring constant is lower than the axial lower wall portion 46.
The upper wall portion 44 in the axial direction is smaller than the upper wall portion 44. The upper and lower wall portions 44, 4 of the pocket portions 42 in the axial direction are provided.
In 6, the elastic center line extending in the radial direction corresponding to the elastic main axis in each of the portions is inclined so as to expand outward in the axial direction.

Further, an orifice cylinder member 60 is attached to the metal sleeve 30 which is vulcanized and bonded to the outer peripheral surface of the rubber elastic body 16 in an externally inserted state. The orifice tube member 60 is formed of a hard material such as a synthetic resin or a metal, and has a cylindrical portion 62 having a large-diameter cylindrical shape as shown in FIGS. An annular projection 64 having a circular plate shape and extending a predetermined length inward in the radial direction is formed integrally with a lower end portion in the axial direction of the cylindrical portion 62.
A concave groove 66 is formed at an intermediate portion in the axial direction of the cylindrical portion 62 so as to extend in the circumferential direction by a length slightly less than one round, and both ends in the circumferential direction of the concave groove 66 are formed on the bottom wall of the concave groove 66. The opening is formed on the inner peripheral surface of the cylindrical portion 62 through communication holes 67 formed through the portion. Further, a pair of divided grooves 68, 68 extending in the circumferential direction of the cylindrical portion 62 with a length of less than half a circumference are formed at positions separated downward in the axial direction of the groove 66. Each of the pair of divided concave grooves 68 extends axially downward at one end in the circumferential direction, and opens at the inner peripheral edge of the annular protrusion 64 through a radial groove 70 formed in the annular protrusion 64. At the other end in the circumferential direction, it is opened to the inner peripheral surface of the cylindrical portion 62 through a communication hole 72 penetrating through the bottom wall.

The orifice cylinder member 60 is
The metal sleeve 30 is attached to the small diameter portion 33 by being extrapolated from below in the axial direction. The inner diameter of the cylindrical portion 62 of the orifice cylindrical member 60 is the same as that of the metal sleeve 3.
0 is slightly larger than the outer diameter of the small diameter portion 33, and the outer diameter of the small diameter portion 33 is
Is approximately the same as the outer diameter dimension of. Further, the axial length of the cylindrical portion 62 is slightly shorter than the axial length of the small diameter portion 33 of the metal sleeve 30, and the axial lower end of the metal sleeve 30 is formed in the annular projection 64 of the orifice cylindrical member 60. The axial upper end of the tubular portion 62 of the orifice tubular member 60 is positioned so as not to slightly reach the step portion 31 of the metal sleeve 30 under the condition that the tubular portion 62 is positioned in the axial direction by being brought into contact with the metal sleeve 30. . The step 31 of the metal sleeve 30
A gap between the tip end of the tubular portion 62 of the orifice tubular member 60 is filled with a filling rubber 74 integrally formed with the main rubber elastic body 16.

On the other hand, the second mounting member 14 has a bottomed cylindrical shape having a cylindrical wall portion 52 and a bottom wall portion 50 having a larger diameter than the metal sleeve 30. Here, the cylindrical wall portion 52
Has an axial length slightly shorter than the metal sleeve 30, while a central central hole of the bottom wall 52 is formed with a circular central through hole 54, and a movable rubber plate is formed in the central through hole 54. Reference numeral 56 is provided in an extended state. This movable rubber plate 5
Numeral 6 has a disk shape of a predetermined thickness, and the outer peripheral edge portion is vulcanized and adhered to the peripheral edge portion of the central through hole 54, so that the central through hole 54 is covered in a fluid-tight manner. A thin seal rubber layer 58 is formed on the inner surface of the second mounting member 14 over substantially the entire surface.

The second mounting member 14 is externally inserted from below in the axial direction with respect to the integrally vulcanized molded product of the main rubber elastic body 16, and is attached to the outer peripheral surfaces of the metal sleeve 30 and the orifice tube member 60. It is fitted and fixed. The fitting portion of the second mounting member 14 to the metal sleeve 30 and the orifice tube member 60 is sealed with a seal rubber layer 58 sandwiched therebetween. Also, the second mounting bracket 14
After the extrapolation and assembly to the main rubber elastic body 16, the cylindrical wall portion 52 is subjected to diameter reduction processing such as octagonal drawing if necessary, and the cylindrical wall portion 52 is formed on the metal sleeve 30 or the orifice cylindrical member 60. The metal sleeve 30 is fixed to the upper end of the metal sleeve 30 in the axial direction by caulking the peripheral edge of the opening.

As a result, the opening of the circular recess 40 formed in the main rubber elastic body 16 is covered with the bottom wall portion 50 of the second mounting member 14 in a fluid-tight manner. Is formed in the axial liquid chamber 80. Also,
A pair of pockets 4 formed in the main rubber elastic body 16
Window 3 of metal sleeve 30 forming openings 2 and 42
4 and 34 are fluid-tightly covered with the cylindrical wall portion 52 of the second mounting member 14, so that the support shaft portion 20 of the first mounting member 12 is opposed to the support shaft portion 20 in a direction perpendicular to the axis. A pair of perpendicular liquid chambers 82, 82 filled with an incompressible fluid.
Are formed. In addition, water, alkylene glycol, polyalkylene glycol, silicone oil, a mixture thereof, or the like is preferably used as the liquid to be filled in the axial liquid chamber 80 and the axial liquid chambers 82, 82. In order to effectively obtain an anti-vibration effect based on the resonance action of the fluid that is caused to flow through the orifice passage described later, a low-viscosity fluid having a viscosity of 0.1 pa · s or less is advantageously employed.

A concave groove 66 formed in the orifice cylindrical member 60 is covered with the cylindrical wall 52 of the second mounting member 14 in a fluid-tight manner.
A second orifice passage 84 that communicates with each other is formed. Furthermore, each pair of divided concave grooves 68, 68 and radial grooves 70,
70 is also covered by the second mounting member 14 in a fluid-tight manner, so that the axial liquid chamber 80 is
A pair of first orifice passages 86, 86 respectively communicating with 82 are formed independently of each other.

The engine mount 10 having the above-described structure is, for example, as shown in FIG.
The second mounting member 14 is press-fitted and fixed to the cylindrical bracket 90, and a mounting leg portion 92 of the cylindrical bracket 90 extends axially downward from the second mounting member 14. Is fixed to the vehicle body 94 in a state where the central axes of the first and second mounting brackets 12 and 14 which become the central axes of the mounts extend in a substantially vertical direction. On the other hand, the first mounting member 12 is fixed to a power unit (not shown) by a bolt or the like, whereby the power unit is supported on the body 94 by vibration isolation. In this mounting state, the first mounting bracket 1
A power unit supporting load is applied vertically between the second mounting bracket 14 and the second mounting bracket 14, and the main rubber elastic body 16 is elastically deformed by a predetermined amount.

In particular, in the case of an FF side-mounted engine, on both sides of the power unit in the vehicle left-right direction in which the crankshaft extends, each is positioned substantially on the inertia main shaft, and a pair of liquids in a direction perpendicular to the shaft are provided. The chambers 82 are arranged so as to face each other in the vehicle front-rear direction.

When a substantially vertical vibration load is input between the first mounting bracket 12 and the second mounting bracket 14 in such a mounted state, the elastic deformation of the main rubber elastic body 16 occurs. And the axial liquid chamber 80 and the liquid chambers 82, 8 perpendicular to the axis.
A relative pressure difference is created between the two,
When the input vibration is a low-frequency large-amplitude vibration such as an engine shake, a high damping effect is exerted based on the resonance action of the fluid flowing through the first orifice passage 86, and the input vibration is a high-frequency vibration such as a muffled sound. In the case of the small amplitude vibration, the axial liquid chamber 8 is formed based on the elastic deformation of the movable rubber plate 56.
The pressure fluctuation of 0 is absorbed and reduced, and the vibration insulating effect by the low dynamic spring action is exhibited.

On the other hand, the first mounting bracket 1
When a substantially horizontal vibration load directed in the vehicle front-rear direction is input between the second mounting bracket 14 and the second mounting bracket 14, a relative pressure difference is generated between the pair of liquid chambers 82 in the direction perpendicular to the axis. Thus, based on the resonance action of the fluid flowing through the second orifice passage 84, an effective damping effect can be exerted on low-frequency large-amplitude vibration such as engine shake.

There, such an engine mount 1
In the case of 0, a pair of right-axis liquid chambers 82, 82 in which relative pressure fluctuations occur when vibration is input in a direction perpendicular to the axis.
Is used to form a liquid chamber in which a relative pressure fluctuation is generated with respect to the axial liquid chamber 80 when an axial vibration is input, so that the axial liquid chamber 80 is input when the axial vibration is input.
The size in the direction of the center axis of the mount can be set smaller than that of an engine mount having a conventional structure in which an equilibrium chamber in which relative pressure fluctuation is generated is separately formed.

By reducing the size of the engine mount 10 in the axial direction, the engine mount 10
In addition to this, in addition to the case where the second mounting bracket is fixed to the automobile body 94 at the lower end in the axial direction using, for example, a cylindrical bracket 90 as shown in FIG. It is possible to set the fixing portion of the second mounting member 14 to the vehicle body 94 closer to the center of the support spring of the main rubber elastic body 16, whereby the second mounting member 14 can be fixed. The reduction of the moment exerted on the fixing portion to the vehicle body, and the improvement of the strength characteristics and durability of the fixing portion based on the reduction can be more effectively achieved.

Further, the engine mount 1 of the present embodiment
At 0, since the thickness of the axial lower wall portion 46 of the pair of liquid chambers 82 at right angles to the axial direction is set large, the axial liquid chamber 80 formed by the axial lower wall portion 46 is formed. Is increased, the escape of pressure fluctuations generated in the axial liquid chamber 80 when the axial vibration load is input into the liquid chambers 82, 82 at right angles to the axis is effectively suppressed. The relative pressure fluctuation between the axial liquid chamber 80 and the liquid chambers 82, 82 at the time of inputting the axial vibration load is efficiently generated, and the fluid flows through the first orifice passage 86. When the amount is more advantageously secured, the vibration damping effect based on the resonance action of the fluid can be more effectively exerted.

Although the embodiments of the present invention have been described in detail above, these are merely examples, and the present invention
By specific descriptions in these embodiments,
It is not to be construed as limiting.

For example, the specific structure of the first orifice passage and the second orifice passage, the length of the passage, the cross-sectional area of the passage, and the like are appropriately determined according to the required vibration isolation characteristics. It is not limited at all. Here, the first orifice passage and / or the second orifice passage can be tuned so as to exhibit an effective vibration damping effect against idling vibration according to required characteristics. Depending on the required characteristics, the first orifice passage 86 may be connected to the axial liquid chamber 80 so that the first orifice passage 86 is used to form the second orifice passage 84. .

In the above embodiment, the axial liquid chamber 80 is provided.
A part of the wall portion is constituted by the movable rubber plate 56 that absorbs the pressure fluctuation in the high frequency range, but such a movable rubber plate 56 is not necessarily required in the present invention.

Further, in the above embodiment, the present invention is applied to F
Although the present invention has been described with respect to an application to an engine mount for an F-type horizontal engine, the present invention is also applicable to engine mounts having various structures, body mounts, differential mounts, and vibration damping devices for various vibration bodies other than automobiles. It goes without saying that any of them can be applied.

In addition, although not enumerated one by one, the present invention
Based on the knowledge of those skilled in the art, various changes, modifications, improvements, and the like can be made, and unless such embodiments depart from the spirit of the present invention.
Both are included in the scope of the present invention,
Needless to say.

[0043]

As is apparent from the above description, in the fluid-filled type vibration damping device having the structure according to the present invention, a pair of right-angle shafts in which relative pressure fluctuations occur when vibration is input in the direction perpendicular to the shafts. By using the directional liquid chamber, a liquid chamber is generated in which a relative pressure fluctuation is generated with respect to the axial liquid chamber when an axial vibration is input. Since the size of the vibration isolator in the direction of the central axis can be set smaller than that of the conventional fluid-filled type vibration isolator in which an equilibrium chamber in which relative pressure fluctuation is generated is separately formed. is there.

Therefore, in such a fluid-filled vibration damping device, the space for disposing the fluid-filled vibration damping device can be reduced, and the first and second orifice passages can be formed by a single orifice member. Thus, the number of parts and the number of assembling steps can be reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory longitudinal sectional view showing an engine mount as one embodiment of the present invention, and is a view corresponding to an II section in FIG. 2;

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

FIG. 3 is a front view showing an orifice member constituting the engine mount shown in FIG. 1;

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

[Explanation of symbols]

 Reference Signs List 10 engine mount 12 first mounting bracket 14 second mounting bracket 16 main body rubber elastic body 20 support shaft part 44 axial upper wall part 46 axial lower wall part 80 axial liquid chamber 82 axial liquid chamber 84 second Orifice passage 86 First orifice passage

Claims (4)

[Claims] A first mounting member provided with a rod-shaped support shaft; a cup-shaped mounting member having the cup-shaped mounting member, the first mounting member being spaced apart from an opening of the first mounting member; A second mounting member in which a support shaft portion of the member is axially inserted from the opening and is positioned; and a step portion is provided in an intermediate portion in the axial direction, and a small-diameter portion sandwiches the step portion in the axial direction. A large-diameter portion is formed, and a pair of windows that are opposed to each other in one direction in the radial direction is provided at an intermediate portion in the axial direction, and the metal is separated and arranged on the outer peripheral side of the support shaft portion of the first mounting member. A sleeve, disposed between a support shaft of the first mounting member and a radially opposed surface of the metal sleeve, and vulcanized and bonded to the support shaft and the metal sleeve; The metal sleeve is positioned opposite to the metal sleeve in a direction perpendicular to the axis with the support shaft of the mounting member interposed. A main body rubber elastic body having a pair of pockets opened to the outer peripheral surface through a pair of windows formed therein, and the metal sleeve is inserted and fixed to a cylindrical wall of the second mounting member, and the second The opening of the mounting member is closed in a fluid-tight manner by the main rubber elastic body, so that a part of the wall is formed by the main rubber elastic body, and the axial direction of the support shaft portion of the first mounting member. An axial liquid chamber formed between the distal end portion and the bottom wall portion of the second mounting member, the pressure fluctuation being generated by the input of the axial vibration load, and the pair of the metal sleeves The window portion is closed in a fluid-tight manner by the cylindrical wall portion of the second mounting member, so that the window is opposed to the inside of the main rubber elastic body in the direction perpendicular to the axis with the support shaft portion of the first mounting member interposed therebetween. It is formed by input of the vibration load perpendicular to the axis. A pair of perpendicular liquid chambers in which pressure fluctuations are generated, incompressible fluids respectively filled in the axial liquid chamber and the pair of perpendicular liquid chambers, and a cylindrical portion; An annular portion extending radially inward from one end in the axial direction, wherein the cylindrical portion is externally fitted to the small diameter portion of the metal sleeve, and the small diameter portion and the cylindrical shape of the second mounting member are provided. The annular portion is sandwiched between the axial end of the small-diameter portion of the metal sleeve and the bottom wall of the second mounting member, so that the metal sleeve and the metal sleeve have the same shape. An orifice member fixedly attached to the second mounting member; and a first orifice passage formed by the orifice member, the first orifice passage communicating the axial liquid chamber to the pair of orthogonal liquid chambers. And formed by the orifice member Fluid filled type vibration damping device, characterized in that the second orifice passage occupying passed, communicating the pair of axis-perpendicular direction liquid chamber to each other, has. 2. A small-diameter portion of the metal sleeve is formed to have an axial length extending to a portion where the window portion is formed, and a cylindrical portion of the orifice member externally inserted into the small-diameter portion is provided on the pair of shafts. 2. The fluid filled type vibration damping device according to claim 1, wherein the device is extended to a liquid chamber in a right angle direction. 3. An expansion spring constant of an elastic wall portion axially outward in the pair of liquid chambers perpendicular to the axis is smaller than an expansion spring constant of an elastic wall portion inward in the axial direction. The fluid filled type vibration damping device as described in the above. 4. A through hole is formed in a bottom wall portion of the second mounting member which forms a part of a wall portion of the axial liquid chamber,
4. The fluid filled type vibration damping device according to claim 1, wherein said through hole is covered with a movable rubber plate in a fluid-tight manner.