JP2631590B2 - Fluid filled type vibration damping device - Google Patents

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 used for an engine mount of an automobile.

[0002]

2. Description of the Related Art The characteristics required of such a fluid-filled type vibration damping device are high damping at low frequency vibration and low vibration transmissibility at high frequency vibration. Of these, regarding the damping property, the rubber elastic body constituting the side wall of the fluid chamber must be weak due to the elastic modulus, etc. There is a tendency that the volume change does not sufficiently occur only by expanding outward. For this reason, Japanese Patent Application Laid-Open No. 1-164831 discloses a technique in which a rigid restraining member is bridged between both side walls, and the restraining members restrain both side walls to suppress outward bulging during compression. Can be This achieves its purpose, but if such a restraining member is stretched between the side walls, the elastic modulus of the side walls is increased, and the vibration transmissibility in a high frequency range is deteriorated. Further, if a different elastic member is buried in the rubber elastic body, a crack may occur in the contact surface of the rubber elastic body.

On the other hand, the vibration load applied to this type of fluid-filled type vibration damping device is not sufficient to be understood only in the vertical direction (direction in which the weight of the support is applied) which is the main vibration load direction.
The same applies to the left-right direction and the front-back direction (axial direction).
FIG. 13 is a plan view in which an automobile engine B is supported on a frame C with this type of fluid-filled type vibration damping device A.
Two fluid-filled anti-vibration devices A are used on the left and right sides, and the outer cylinder side is fixed to the frame C and the inner cylinder side is fixed to the engine B. As can be seen from this, it can be easily understood that the engine B vibrates in all directions due to acceleration / deceleration and braking of the vehicle or unevenness of the road. Further, depending on the type of engine, it is expected that the rate of load applied in directions other than the vertical direction will further increase. Therefore, both the damping property and the vibration transmissibility must satisfy the vibration loads from these three directions.

[0004]

[Problems to be solved by the invention]
The applicant has provided a rubber elastic support column having a mass body that penetrates through a main fluid chamber (a fluid chamber on the pressure receiving side) to integrally connect the side walls and bridges the inner and outer cylinders in the load direction. The proposed case was previously proposed as Japanese Patent Application No. 2-133578.
This elastic strut suppresses the outward bulging of the side wall during compression and prevents sagging, and also satisfies vibration loads from three directions. An almost ideal type of vibration isolator was realized.

However, recently, this type of fluid-filled type vibration damping device has been applied to a small vehicle model, and when the size of the device has been reduced to meet the demand, such an elastic strut has a mass. It is divided into upper and lower parts, and the strain rate against the vibration load increases, so that durability cannot be secured. In addition, in order to ensure durability, the rigidity must be high, and as a result, a desired vibration transmissibility cannot be obtained. The present invention solves such a problem, and in short, proposes a fluid-filled anti-vibration support device that is not dissatisfied with damping properties and vibration transmissibility even in a small fluid-filled anti-vibration device. Is what you do.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an inner cylinder and an outer cylinder which are arranged concentrically or eccentric in the vertical direction with a space between the inner cylinder and the outer cylinder at right angles to the cylinder axis. A non-compressible fluid is sealed by the side walls of the two rubber elastic bodies interposed between the rubber elastic body and a partition wall of the same rubber elastic body which is integrally bridged in parallel with the cylinder axis including the inner cylinder between the side walls. In a fluid-filled type vibration damping device in which a main fluid chamber and a sub fluid chamber are separated below and above the partition and the main and sub fluid chambers are communicated with an orifice structure, the inner cylinder and the outer cylinder are provided in the main fluid chamber. Independently of the cylinder, it is formed integrally with the both side walls in parallel with the cylinder axis and has a thickness greater than at least the distance between any of the inner cylinder side and outer cylinder side opposing members bridging between the both side walls. A connecting band of rubber elastic body is provided, and the connecting band is separated from the both side walls. To provide a fluid filled type vibration damping device formed by sealing the mass inside parts.

[0007] The present invention also provides a side wall of two rubber elastic bodies interposed at right angles to a cylinder axis at an interval between an inner cylinder and an outer cylinder arranged concentrically or eccentric in the vertical direction. When,
A main fluid chamber and a sub-fluid chamber for filling an incompressible fluid with a partition wall of the same rubber elastic body which is integrally bridged in parallel with the cylinder axis including the inner cylinder between the side walls, and a lower fluid chamber below the partition wall. In a fluid-filled type vibration damping device which is separated from the upper side and communicates these master and slave fluid chambers with an orifice structure, the main fluid chamber is connected to the inner cylinder and rubber elastic body in a vertical direction by connecting columns. At least the inner cylinder side which is formed integrally with the both side walls and the connecting column in parallel to the cylinder axis and bridges between the both side walls,
A fluid-sealed type protection device in which a rubber elastic connecting band having a thickness greater than the distance between any of the outer cylinder side opposing members is provided, and a mass body is sealed inside a central portion of the connecting band separated from the side walls. A vibration device is provided.

Further, the present invention is directed to a side wall of two rubber elastic bodies interposed at right angles to a cylinder axis with an interval between an inner cylinder and an outer cylinder arranged concentrically or eccentric in the vertical direction. A main fluid chamber and a sub-fluid chamber for filling an incompressible fluid with the same rubber elastic partition wall which is integrally bridged parallel to the cylinder axis including the inner cylinder between the side walls, In a fluid-filled type vibration damping device in which the lower and upper fluid chambers are communicated with an orifice structure in a lower and upper space, the main fluid chamber is vertically connected by a connecting column of the outer cylinder and a rubber elastic body. In a state, the rubber elasticity is formed integrally with the both side walls and the connecting column in parallel with the cylinder axis and has a thickness greater than at least the distance between any of the inner cylinder side and the outer cylinder side opposing members bridging between the both side walls. A central part of the connecting band of the body, which is separated from the side walls; To provide a fluid filled type vibration damping device formed by sealing the interior mass.

[0009]

By taking the above-mentioned means, that is, by providing a connecting band having a large cross-sectional area which is integrally bridged between both side walls in the main fluid chamber, when the main fluid chamber is contracted, the side wall is formed. Reduces a wide range of inflation attempts. Of course, since the connecting band is integrally formed with the same member as the side wall, there is no problem in durability. Further, at this time, since a part of the connection band is replaced by the mass body, the rigidity of the remaining rubber elastic portion is relatively increased and the effect of suppressing the bulging of the side wall is further increased. Therefore, a change in volume of the fluid chamber during vibration is promoted, and a high damping property is exhibited. On the other hand, the bridging direction of the connecting band is not the vertical direction but the horizontal direction perpendicular to the vertical direction, and a part of this is replaced by a mass body having a sufficient mass. The transmissivity is kept low and the vibration absorption is high. Thus, both damping and vibration transmissibility
It works in a more favorable direction.

The above-mentioned connecting band is independent of the inner tube or the outer tube. However, if the connecting band, the inner tube and the outer tube are connected by a connecting column made of a rubber elastic body, the mass can be reduced. The degree of freedom in tuning design of the resonance frequency in three directions is increased without reducing the damper effect of the body.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a partial cross-sectional view of a fluid-filled vibration damping device according to the present invention, FIG. 2 is a vertical sectional view, and FIG. 3 is a front view. , Two rubber elastic body side walls 12 provided at an interval,
Two spaces 16, 18 open to the outer periphery at upper and lower positions sandwiching the partition wall 14 with the partition wall 14 of the same rubber elastic body which is wing-likely extended in the left-right direction from both sides of the inner cylinder 10 and integrally bridged between the two. Is mounted eccentrically upward (in the direction in which the load is applied). And this space 1
An incompressible fluid is sealed in each of the tubes 6, 18, and an outer cylinder 22 is fitted around the outer periphery of the cylindrical body 20, and the lower one of the fluid sealed spaces 16, 18 is the main fluid chamber 16, and the upper one is the slave fluid. The room 18 is used. The lower end of the main fluid chamber 16, that is, the cylindrical body 20
At the lower end, a cross-linking band 15 made of a rubber elastic body is formed to integrally bridge between the side walls 12 as in the case of the partition wall 14.

According to the present invention, a connecting band 24 made of a rubber elastic material is provided in the main fluid chamber 16 so as to be integrally bridged between the side walls 12 in parallel with the cylinder axis, and a part of the connecting band 24 is formed. That is, the mass 26 is replaced. Thus, this connecting band 2
4 is at least wider than the diameter of the inner cylinder 10 and the opposing members (the inner cylinder 10
The side has a greater cross-sectional area than the partition 14 and the outer cylinder 22 has a thickness greater than the gap with the bridge band 15). By providing such a connecting band 24, when a compressive load is applied to the side wall 12, it is possible to prevent the side wall 12 from simply bulging outward and becoming in a state of crouching. The reason why a part of the connecting band 24 is replaced by the mass body 26 is to increase the rigidity of the remaining connecting band 24 to increase the effect of suppressing bulging, and to cause the mass body 26 to exhibit a damper effect. That's why. Therefore, the specific gravity of the mass body 26 and its replacement amount can be used as tuning elements for adjusting the frequency. Further, the connecting band 24
Are independently provided in the main fluid chamber 16 (the partition 14 and the bridging zone 15
Crosslinking is also preferable from the viewpoint of the damper effect. Since the connecting band 24 also serves as a stopper for restricting the inner cylinder 10 and the outer cylinder 22 from being displaced more than a predetermined value, a stopper for another object is provided inside or outside the main fluid chamber 16 as in the related art. This need not be done, and cost reduction from this aspect is also possible.

In addition, a through-hole 2 penetrating between the side walls 12 is provided on the side of the partition wall 14 on the side of the slave fluid chamber 18 in order to enhance durability.
A main mass portion 30 extending to the outer periphery of the cylindrical body 20 is provided on the center outer peripheral portion of the remaining portion, and a diaphragm which is thinly curved toward the main fluid chamber 16 for facilitating the movement of fluid on both sides thereof. The parts 32 are respectively formed. Therefore, the bottom portion of the slave fluid chamber 18 is formed by the diaphragm portion 32 and is divided into right and left by the main mass portion 30. Further, a reinforcing ring 34 which is continuous with the outer peripheral side of the cylindrical body 20 at the side walls 12 and has the fluid chambers 16 and 18 cut out in a window shape is embedded and reinforced.

Next, the main fluid chamber 16 and the sub fluid chamber 18
The space is communicated by an orifice structure 36, and when the volumes of the two fluid chambers 16 and 18 fluctuate due to vibration, the fluid moves accordingly. The orifice structure 36 is provided on the outer periphery of the cylinder 20 on the side of the sub-fluid chamber 18,
A semicircular orifice ring 4 having orifice passages 38 formed on the outer periphery thereof, which respectively communicate with the 6 and the two slave fluid chambers 18.
This is performed by fitting 0. If the orifice ring 40 is formed with a concave portion 42 at the center of the reinforcing ring 34 so as to be fitted therein, the orifice ring 40 is firmly fixed and is unlikely to be displaced. 2
0 Increase the overall rigidity. FIG. 4 is a plan view of the orifice ring 40, and an orifice passage 38 formed therein is shown.
The orifice hole 44 is provided so as to increase the path length of the zigzag to increase the damping property, and to also communicate with the two sub-fluid chambers 18 divided by the main mass 30.

FIGS. 5 and 6 are a horizontal sectional view and a vertical sectional view, respectively, showing another embodiment of the present invention.
4 are not made independent in the main fluid chamber 16,
It is connected to the side. That is, the connecting band 24 and the partition 14
Are connected in the up-down direction by connecting columns 46. By doing so, the degree of freedom in tuning design of the resonance frequency in three directions can be increased without reducing the damper effect of the mass body 26. In addition, if the connecting column 46 is present, the connecting band 24 only needs to consider the restraining effect of the side wall 12, so that the direction in which this exists, that is,
The durability in the vertical direction can be greatly improved.

FIGS. 7 and 8 are also a horizontal sectional view and a vertical sectional view showing another embodiment of the present invention.
Are connected in the up-down direction by the outer cylinder 22 side, that is, the bridging band 15 and the connecting column 48. This effect is the same as that of the above-described embodiment in which the connecting column 46 is provided.

The automobile engine is supported by the vibration isolator having the above-described structure. At this time, the outer cylinder is fixed to the frame, and the weight of the engine is applied to the inner cylinder from the anti-eccentric direction. Attach with As a result, the vibration generated by the engine is blocked from being transmitted to the chassis,
In addition, the generated vibration can be attenuated. In this case, the following effects can be expected.

[0018]

According to the present invention, a load is applied to the main fluid chamber by providing a connecting band having a large cross-sectional area bridging between both side walls parallel to the cylinder axis and replacing a part of the center of the connecting band with a mass body. Sometimes, deformation of the side wall is suppressed, and the amount of fluid movement between the master and slave fluid chambers increases. Vibration energy is consumed by such sufficient fluid movement, and the damping effect increases. FIG. 9 shows a vertical loss factor (tan δ) perpendicular to the cylinder axis.
-Looking at the frequency characteristics, it can be seen that the loss factor of the connection band partially provided with a mass body (hereinafter referred to as the present invention) is lower than that of the conventional product having no such connection band. It turns out that it is big.

By adjusting the replacement amount of the mass body in the connecting band, the rigidity ratio between the vertical direction, the horizontal direction, and the front-back direction can be changed, thereby sacrificing durability which has been a problem in the past. Without this, it is possible to satisfy the vibration transmission effect in three directions at the same time. Further, the resonance point can be moved by changing the rigidity. Furthermore, the presence of this mass also improves the static characteristics when the spring constant is matched in the vicinity of the vertical direction 1 W (engine sharing load). FIG. 10 shows the load-deflection characteristics, and it can be seen that the product of the present invention has less deflection against a vertical load. This leads to an increase in durability.

In the case where the rubber elastic strut is provided in the main fluid chamber proposed by the present applicant, the resonance point appears in the high frequency range of 400 to 500 Hz which is the frequency during normal running of the vehicle. This can be avoided by bridging the rubber elastic connecting band, whose central part has been replaced by a mass between the walls, and separating this mass from the side walls. FIG. 11 shows an absolute spring constant-frequency characteristic in the vertical direction, but the resonance point of the product of the present invention does not exist near 400 to 500 Hz.
That is, the vibration transmissibility is reduced, which contributes to the improvement of riding comfort.

Further, the product of the present invention lowers the absolute spring constant in the front-rear direction, that is, the vibration transmissibility in a high frequency range. FIG. 12 shows the absolute spring constant-frequency characteristics in the front-rear direction. The resonance point of the product of the present invention moves to a low frequency range outside 300 to 500 Hz, which also contributes to improvement of the riding comfort. As described above, even if this fluid-filled type vibration damping device is a small one that has never been seen before, the original damping effect can be further enhanced, and the vibration transmission characteristics in all directions can be tuned over a wide frequency range. It was possible to realize what was almost ideal.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a fluid-filled type vibration damping device.

FIG. 2 is a longitudinal sectional view of a fluid-filled type vibration damping device.

FIG. 3 is a front view of the fluid filled type vibration damping device.

FIG. 4 is a plan view of an orifice ring.

FIG. 5 is a cross-sectional view of the fluid filled type vibration damping device.

FIG. 6 is a longitudinal sectional view of the fluid filled type vibration damping device.

FIG. 7 is a cross-sectional view of the fluid filled type vibration damping device.

FIG. 8 is a longitudinal sectional view of the fluid filled type vibration damping device.

FIG. 9 shows a vertical loss factor (tan δ) -frequency characteristic.

FIG. 10 shows load-deflection characteristics.

FIG. 11 is an absolute spring constant-frequency characteristic in the vertical direction.

FIG. 12 is an absolute spring constant-frequency characteristic in the front-rear direction.

FIG. 13 is a plan view showing an attached state of the engine and the chassis.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Inner cylinder 12 Side wall 14 Partition wall 16 Main fluid chamber 18 Secondary fluid chamber 22 Outer cylinder 24 Connecting band 26 Mass body 36 Orifice structure 46 Connecting column 48 Connecting column

Claims (3)

(57) [Claims] 1. A side wall of two rubber elastic bodies interposed at right angles to a cylinder axis at an interval between an inner cylinder and an outer cylinder arranged concentrically or eccentric in the vertical direction, and the side walls. Between
A main fluid chamber and a sub-fluid chamber for enclosing an incompressible fluid are separated from each other below and above the partition by a partition made of the same rubber elastic body which is integrally bridged in parallel with the cylinder axis including the inner cylinder. In the fluid-filled type vibration damping device in which the master and slave fluid chambers communicate with each other by an orifice structure, the main fluid chamber is integrated with the side walls in parallel to the cylinder axis in a state independent of the inner cylinder and the outer cylinder. Formed at a width wider than at least the diameter of the inner cylinder bridging between the both side walls, and facing the inner cylinder and the outer cylinder.
Material either the connecting zone of Lugo arm elastic member having a larger thickness than the spacing provided in the fluid-filled proof formed by sealing the mass inside the central portion wherein the off both side walls of the connecting band Shaking device. 2. Side walls of two rubber elastic bodies interposed at right angles to the cylinder axis with an interval between an inner cylinder and an outer cylinder arranged concentrically or eccentric in the vertical direction, and the side walls. Between
A main fluid chamber and a sub-fluid chamber for enclosing an incompressible fluid are separated from each other below and above the partition by a partition made of the same rubber elastic body which is integrally bridged in parallel with the cylinder axis including the inner cylinder. In the fluid-filled type vibration damping device in which the master and slave fluid chambers communicate with each other in an orifice structure, the main fluid chamber is parallel to the cylinder axis in a state where the inner cylinder and the rubber elastic body are vertically connected by a connecting column. At least the inner cylinder side and the outer cylinder side facing portions which are formed integrally with the both side walls and the connecting column and bridge between the two side walls.
Material either the connecting zone of Lugo arm elastic member having a larger thickness than the spacing provided in the fluid-filled proof formed by sealing the mass inside the central portion wherein the off both side walls of the connecting band Shaking device. 3. Side walls of two rubber elastic bodies interposed at right angles to the cylinder axis with an interval between an inner cylinder and an outer cylinder arranged concentrically or eccentric in the vertical direction, and the side walls. Between
A main fluid chamber and a sub-fluid chamber for enclosing an incompressible fluid are separated from each other below and above the partition by a partition made of the same rubber elastic body which is integrally bridged in parallel with the cylinder axis including the inner cylinder. In the fluid-filled type vibration damping device in which the master and slave fluid chambers communicate with each other in an orifice structure, the main fluid chamber is parallel to the cylinder axis in a state where the outer cylinder and the rubber elastic body are vertically connected to each other. At least the inner cylinder side and the outer cylinder side facing portions which are formed integrally with the both side walls and the connecting column and bridge between the two side walls.
Material either the connecting zone of Lugo arm elastic member having a larger thickness than the spacing provided in the fluid-filled proof formed by sealing the mass inside the central portion wherein the off both side walls of the connecting band Shaking device.