JPH053791Y2 - - Google Patents

Description

[Detailed description of the invention] (Technical field) The present invention relates to a fluid-filled mount device such as an automobile engine mount, and has a particularly good vibration isolation effect (damping or blocking effect) against input vibration in a wide frequency range. This invention relates to a fluid-filled mounting device that can exhibit the following properties.

(Prior Art) Mounting devices such as automobile engine mounts are generally required to exhibit good vibration isolation effects against both low-frequency, large-amplitude input vibrations and high-frequency, small-amplitude input vibrations. Among them,
It is required to exhibit a good damping effect against low-frequency, large-amplitude input vibrations. Therefore, in recent years, as such a mounting device, (a) first and second supports arranged at a predetermined distance in the main vibration input direction, and (b) the first support and the second (c) a rubber elastic body disposed on the side of the second support and partially defined by the rubber elastic body; (d) a predetermined incompressible fluid sealed within the fluid accommodation space; (e) A so-called so-called partitioning member that partitions the fluid storage space into a pressure receiving chamber on the rubber elastic body side and an equilibrium chamber on the partition wall member side, and (f) a throttle passage that allows the pressure receiving chamber and the equilibrium chamber to communicate with each other. Fluid-filled mounting devices have been proposed.

According to the fluid-filled mounting device having such a structure, when vibration in the main vibration input direction is input between the first support body and the second support body, the vibration load causes the rubber elastic body to Based on the deformation of the incompressible fluid in the pressure receiving chamber and the equilibrium chamber, the incompressible fluid in the pressure receiving chamber and the equilibrium chamber are caused to flow into each other through the constriction passage, and liquid column resonance is induced in the frequency range set for the constriction passage. . and,
Based on the resonance action of the liquid column resonance, an excellent vibration damping effect can be obtained in the frequency range set for the throttle passage, and therefore, by tuning the throttle passage to a low frequency, it is possible to respond to that tuning frequency. This makes it possible to satisfactorily attenuate large-amplitude vibrations in the low frequency range.

However, in a fluid-filled mounting device having such a structure, as described above, although it can exhibit a good damping effect against input vibration in a low frequency range corresponding to the tuning frequency of the throttle passage, Good vibration isolation effects cannot necessarily be achieved against input vibrations in other frequency ranges, and especially against input vibrations in a frequency range higher than the frequency range corresponding to the tuning frequency of the throttle passage. However, since it becomes difficult for the incompressible fluid to flow through the throttle passage, there is a problem in that the vibration damping function is deteriorated.

On the other hand, in a fluid-filled mounting device having the structure as described above, (g) a movable means is disposed so as to be deformed or displaced by a predetermined amount so as to absorb the fluid pressure difference between the pressure receiving chamber and the equilibrium chamber. A fluid-filled mounting device has been proposed. According to a fluid-filled mount device equipped with such a movable means, liquid column resonance of an incompressible fluid caused by deformation or displacement of the movable means according to the fluid pressure difference between the pressure receiving chamber and the equilibrium chamber. Based on this action, small amplitude vibrations in the frequency range set for the movable means can be effectively blocked, and therefore by setting the tuning frequency for the movable means at a relatively high frequency, Small amplitude vibrations in a relatively high frequency range corresponding to the tuning frequency of the movable means can be effectively blocked.

(Problem) However, even in a fluid-filled mounting device with such a structure, there is a large amplitude vibration in a low frequency range set for the throttle passage, and a small amplitude vibration in a relatively high frequency range set for the movable means. Although a good damping or blocking effect can be achieved with respect to vibrations, the movable means may be deformed or displaced in response to small amplitude vibrations in a frequency range higher than the frequency range corresponding to the tuning frequency of the movable means. As a result of this, the dynamic spring constant increased significantly, causing problems such as a significant decrease in vibration isolation function.

(Solution Means) The present invention was developed against the background of the above-mentioned circumstances, and its gist is as follows: (a) the first and second supports; and (b) rubber. In a fluid-filled mounting device comprising an elastic body, (c) a partition member, (d) an incompressible fluid, (e) a partition member, and (f) a throttle passage, the rubber elastic body is an inward dish-shaped first deformed portion defining a fluid accommodation space;
The first deformable part and the second deformable part in the shape of an outward dish between the first support body are integrally formed in a substantially X-shaped cross-sectional structure in which the first deformable part and the second deformable part are connected back to back. The static spring constant of the second deformable part in the main vibration input direction is set larger than that of the first deformable part, while the second deformable part of the rubber elastic body is set mainly in the main vibration input direction. The reason is that it has a structure that undergoes shear deformation.

(Function/Effect) In a fluid-filled mounting device with such a structure, when vibration is input between the first support body and the second support body, the rubber elastic body is deformed by the vibration load. However, as mentioned above, in the present invention, the first deformed portion of the rubber elastic body that defines the fluid storage space is more likely to be connected to the first support member. Since the static spring constant in the main vibration input direction is smaller than that of the second deformed part between the It will be deformed in the first deformation section. In other words, when the frequency of the input vibration is lower than the frequency of the set frequency range for the throttle passage, the rubber elastic body is deformed mainly in the first deformation part, and the change in the first deformation part causes the rubber elastic body to deform mainly in the first deformation part. Therefore, the incompressible fluid can be effectively forced to flow through the throttle passage. Therefore, similar to conventional fluid-filled mounting devices, good vibration damping effects can be obtained in the frequency range set for the throttle passage based on the liquid column resonance effect of the incompressible fluid flowing through the throttle passage. Yes, by setting the tuning frequency of the throttle passage to a low frequency, similar to conventional fluid-filled mounting devices,
Large amplitude vibrations in the low frequency range can be effectively blocked.

On the other hand, in a fluid-filled mounting device with such a structure, when the frequency of input vibration becomes higher than the frequency range set for the restriction passage, it becomes difficult for incompressible fluid to flow through the restriction passage. As the pressure increases, the dynamic spring constant of the first deformed portion of the rubber elastic body substantially increases, but in the present invention, the dynamic spring constant between the first deformed portion and the first support body is increased. Since the second deformable portion of the rubber elastic body is provided in series, even if the dynamic spring constant of the first deformable portion of the rubber elastic body increases significantly, the deformation of the second deformable portion will not Based on this, an increase in the dynamic spring constant of the rubber elastic body as a whole is effectively suppressed. In other words, even if a vibration with a frequency higher than the set frequency range for the throttle passage is input, it is possible to effectively avoid a significant increase in the dynamic spring constant, and therefore it is possible to avoid a significant increase in the dynamic spring constant. It can block small amplitude vibrations in a high frequency range better than the mounting device.

As described above, the fluid-filled mounting device according to the present invention can effectively damp low-frequency, large-amplitude input vibrations, as well as high-frequency, small-amplitude input vibrations, as with conventional fluid-filled mounting devices. Therefore, it is possible to obtain good vibration isolation characteristics in a wider frequency range than conventional fluid-filled mount devices. In addition, if the fluid-filled mount device according to the present invention is also provided with a movable means similar to the conventional one, an even better vibration isolation effect can be obtained in the frequency range corresponding to the tuning frequency of the movable means. It happens.

In addition, in the fluid-filled mount device according to the present invention, the rubber elastic body has a substantially X-shaped cross-sectional structure, and the second deformation part is structured to undergo shearing deformation exclusively in the main vibration input direction. , compared to the case where the structure of the second deformation part is compressively deformed exclusively in the main vibration input direction.
There are advantages in that the durability of the rubber elastic body can be improved and the mounting device can be configured compactly.

In other words, the static spring constant of the second deformable portion of the rubber elastic body in the main vibration input direction needs to be set larger than that of the first deformed portion of the rubber elastic body. If the static spring constant of the second deformable portion is made too large, the isolation characteristics against small amplitude vibrations will be impaired, so it is necessary to suppress the static spring constant of the second deformable portion to a certain level. Therefore, when the structure of the second deformation part is such that it is compressively deformed exclusively in the main vibration input direction, it is necessary to increase the thickness of the second deformation part in the compressive deformation direction (main vibration input direction). Alternatively, it is necessary to reduce the cross-sectional area in the direction perpendicular to the compressive deformation direction, but if the thickness of the second deformable part in the compressive deformation direction is increased, the mounting device will inevitably become larger. Furthermore, if the cross-sectional area in the direction perpendicular to the compressive deformation direction is reduced, problems such as a significant decrease in the durability of the rubber elastic body occur.

On the other hand, if the second deformation part of the rubber elastic body is structured to undergo shear deformation exclusively in the main vibration input direction as in the present invention, the thickness of the shear deformation part of the rubber elastic body While maintaining a sufficient cross-sectional area, the static spring constant in the main vibration input direction can be suppressed to a certain level, and the dimensions of the second deformation part in the main vibration input direction can be significantly increased. This makes it possible to suppress the static spring constant in the main vibration input direction to a certain level without causing any damage.
It becomes possible to significantly improve the durability of the rubber elastic body, and it also becomes possible to configure the mounting device compactly.

(Example) Hereinafter, in order to clarify the present invention more specifically, an example of the case where the present invention is applied to an engine mount of an automobile will be described in detail based on the drawings.

First, in the automobile engine mount shown in FIG. 1, 10 and 12 are a first support metal fitting and a second support metal fitting as a first support body and a second support body, respectively. They are arranged at a predetermined distance apart in the input direction (vertical direction in the figure).

The first support fitting 10 includes a flat plate part 16 having a relatively large-diameter circular hole 14 approximately in the center thereof, and a tapered tube concentrically connected to the peripheral edge of the circular hole 14 at the small-diameter end. The tapered cylinder part 18 is arranged so that the center line of the circular hole 14 and the tapered cylinder part 18 is parallel to the main vibration input direction, and the tapered cylinder part 18 is located on the second support fitting 12 side. ing.

On the other hand, the second support fitting 12 consists of a substantially cylindrical opening fitting 20 and a cup-shaped bottom fitting 22, and the bottom fitting 22 is connected to the opening fitting at the outward flange portion 24 of the opening. It has a bag-like structure having an opening having approximately the same diameter as the circular hole 14 of the first support fitting 10, which is fluid-tightly caulked and fixed to one end of the support fitting 20. It is arranged concentrically with the tapered cylindrical portion 18 of the first support metal fitting 10 with its internal space opening toward the first support metal fitting 10 side.

And, here, such a second support fitting 12
A rubber elastic body 26 is disposed in such a manner that it is integrally vulcanized and adhered to the inner circumferential surface of the opening of the rubber elastic body 26 and is integrally vulcanized and bonded to the inner circumferential surface of the tapered cylindrical portion 18 of the first support fitting 10. , As a result, the second support fitting 1
The opening of 2 is fluid-tightly closed by the rubber elastic body 26, and the first support fitting 10 and the second support fitting 12 are elastically connected via the rubber elastic body 26. .

Note that the flat plate portion 16 of the first support fitting 10 has the following:
An appropriate number of mounting holes 28 are formed, and mounting bolts 30 are erected on the bottom wall of the bottom metal fitting 22 of the second support metal fitting 12. The engine mount of this embodiment is attached to the engine side or the vehicle body through the mounting hole 28 of the first support metal fitting 10, and is attached to the vehicle body side or the engine side by the mounting bolt 30 of the second support metal fitting 12. It is attached to support the engine or the power unit including the engine against the vehicle body in a vibration-proof manner.

Here, the second support fitting 12 includes an opening fitting 20 and a bottom fitting 2, as shown in the figure.
With the peripheral portion held fluid-tight between 2,
A diaphragm 32 is provided as a partition wall member made of a rubber elastic membrane (flexible membrane). As a result, a sealed space as a fluid storage space is formed between the diaphragm 32 and the rubber elastic body 26, and within this sealed space,
A predetermined incompressible fluid such as water or polyalkylene glycol is sealed. Note that the space between the diaphragm 32 and the bottom metal fitting 22 is an air chamber 34 for allowing the diaphragm 32 to deform.

Furthermore, like the diaphragm 32, a partition member 36 is disposed on the second support fitting 12, with the peripheral edge held fluid-tight between the opening fitting 20 and the bottom fitting 22. The fluid storage space is
The partition member 36 allows a pressure receiving chamber 38 on the rubber elastic body 26 side and an equilibrium chamber 40 on the diaphragm 32 side to be separated.
It is divided into Here, the pressure receiving chambers 38 are
A circumferential throttle passage 42 is formed to allow the first support fitting 1 and the equilibrium chamber 40 to communicate with each other.
0 and the second support fitting 12, the rubber elastic body 26 is elastically deformed by the vibration load, and a fluid pressure difference is induced between the pressure receiving chamber 38 and the equilibrium chamber 40. Then, those pressure receiving chambers 3
8 and the incompressible fluid in the balance chamber 40 are allowed to flow into each other through this throttle passage 42.

More specifically, the partition member 36 has a structure in which a thick wall portion 44 on the outer periphery and a thin wall portion 46 on the inner periphery are integrally molded from a predetermined elastic material such as rubber. The stepped portion 48 formed on the bottom fitting 20 and the outward flange portion 24 of the bottom fitting 22 (strictly speaking,
The thick portion 44 is held between the outer flange 24 of the bottom metal fitting 22 and the peripheral edge of the diaphragm 32 interposed therebetween. The circumferential groove portion 50 formed in the thick wall portion 44 of the partition member 36 has its opening fluid-tightly closed by the stepped surface 48 of the opening fitting 20, so that the circumferential groove portion 50 is A space is formed extending into the partition member 36, and this space is communicated with the pressure receiving chamber 38 and the equilibrium chamber 40 through a notch 52 and a through hole 54 formed in the partition member 36, thereby forming a throttle passage 42. There is.

Note that here, the tuning frequency of the throttle passage 42 is set to a low frequency corresponding to the input frequency range of engine shake, etc., so that the tuning frequency of the throttle passage 42 is set to a low frequency corresponding to the input frequency range of engine shake, etc. Therefore, liquid column resonance is induced in a low frequency range corresponding to the input frequency range of engine shake, etc.

Further, in this embodiment, the thin wall portion 46 of the partition member 36 is configured to be able to deform by a predetermined amount in the direction of absorbing the fluid pressure difference between the pressure receiving chamber 38 and the equilibrium chamber 40. In addition, the tuning frequency of the thin wall portion 46 is set to a relatively high frequency corresponding to the input frequency range of muffled sounds, etc.
Based on the flow of incompressible fluid accompanying the deformation of 6,
Liquid column resonance is induced in the frequency range of around 150Hz, which corresponds to input frequencies such as muffled sounds. That is, here, the thin wall portion 46 of the partition member 36 serves as a movable means.

By the way, as shown in the figure, the opening of the second support fitting 12 is a tapered cylindrical portion 56 that opens toward the first support fitting 10, and the opening of the second support fitting 12 is The rubber elastic body 26 is integrally vulcanized and bonded. Here, the rubber elastic body 26 has two dish-like parts 58 and 60, that is, a dish-like part 58 that expands upward (outward) and a dish-like part 58 that expands downward (inward), as shown in the figure. Direction)
The rubber elastic body 26 is formed with a letter-shaped cross-sectional structure, and the two dish-shaped parts 58,
60 at the opening periphery of the first support fitting 1
0 tapered cylindrical portion 18 and the second support fitting 1
The two tapered cylindrical parts 56 are integrally vulcanized and bonded to each other, so that vibrations in the main vibration input direction are input between the first support metal fitting 10 and the second support metal fitting 12. When the rubber elastic body 26 is
The tapered cylindrical outer peripheral portions of these dish-shaped parts 58 and 60 are mainly subjected to shear deformation, and as the dish-shaped part 60 on the second support fitting 12 side is deformed, the pressure receiving chamber 38 is Fluid pressure is generated to cause incompressible fluid to flow through the restriction passage 42. As is clear from this, here, the dish-shaped part 60 on the second support metal fitting 12 side constitutes the first deformation part of the rubber elastic body 26, and the first support metal fitting 1
The dish-shaped portion 58 on the zero side constitutes the second deformable portion of the rubber elastic body 26.

In the present embodiment, in the rubber elastic body 26 having such a structure, the thickness of the dish-shaped part 58 which is the second deformed part is slightly thicker than that of the dish-shaped part 60 which is the first deformed part. In addition, the opening angle of the dish-shaped part 58 is set to be slightly smaller than that of the dish-shaped part 60, so that the static spring constant of the dish-shaped part 58 in the main vibration input direction is set to be slightly smaller than that of the dish-shaped part 60.
is set sufficiently larger than that of . In addition,
The dish-shaped parts 58 and 60 constituting the rubber elastic body 26 are made of the same rubber material and have sufficient wall thickness.

In the engine mount having such a structure, when vibration in the main vibration input direction is input between the first support metal fitting 10 and the second support metal fitting 12, as described above, the disk-shaped rubber elastic body 26 Since the static spring constant of the portion 58 in the main vibration input direction is sufficiently larger than that of the dish-shaped portion 60, while the flow of the incompressible fluid through the throttle passage 42 is easily allowed, that is, the input When the frequency of the vibration is lower than a frequency approximately equal to the set frequency range for the throttle passage 42, only the dish-shaped portion 60 defining the pressure receiving chamber 38 is elastically deformed. Therefore, when the liquid column of the incompressible fluid flowing through the throttle passage 42 resonates, the incompressible fluid is effectively caused to flow through the throttle passage 42 as the dish-shaped portion 60 of the rubber elastic body 26 deforms. Therefore, similar to the conventional fluid-filled engine mount, based on the liquid column resonance effect of the incompressible fluid flowing through the throttle passage 42, the input vibration in the frequency range set for the throttle passage 42, that is, the engine A good damping effect can be achieved against low frequency, large amplitude input vibrations such as shake.

In addition, the first support metal fitting 10 and the second support metal fitting 1
The frequency of the vibration input between the throttle passage 4 and the
When the frequency becomes higher than the set frequency range for 2, it becomes difficult for the incompressible fluid to flow through the throttle passage 42, so the fluid pressure in the pressure receiving chamber 38 increases and the movement of the dish-shaped portion 60 of the rubber elastic body 26 is reduced. Although the spring constant will substantially increase, if the input vibration has a frequency of around 150Hz, as described above, the incompressible fluid will Since liquid column resonance is induced, the dynamic spring constant can be favorably reduced based on the liquid column resonance effect. In other words, it exhibits a good blocking effect against small-amplitude vibrations such as muffled sounds in the frequency range of around 150Hz.

On the other hand, in this embodiment, as described above, since the dish-shaped part 58 of the rubber elastic body 26 is interposed between the dish-shaped part 60 and the first support fitting 10, even if the input vibration is The frequency becomes higher than the set frequency range for the thin wall portion 46 of the partition member 36, and the flow of the incompressible fluid through the throttle passage 42,
In addition, even if the flow of the incompressible fluid becomes difficult due to the deformation of the thin wall portion 46 of the partition member 36, and the dynamic spring constant of the dish-shaped portion 60 increases significantly, the dish-shaped portion 5
8, the increase in the dynamic spring constant of the rubber elastic body 26 as a whole is effectively suppressed. In other words, the frequency of the input vibration is
To satisfactorily avoid a significant increase in the dynamic spring constant of the entire rubber elastic body 26 due to deformation of a dish-shaped portion 58 of the rubber elastic body 26 even when the frequency is higher than the set frequency range for the thin wall portion 46 of the rubber elastic body 26. Therefore, it has a better blocking effect than conventional engine mounts against small amplitude vibrations such as engine transmitted sound in a frequency range higher than the frequency range set for the thin wall portion 46 of the partition member 36. It is possible to demonstrate this.

As explained above, according to the engine mount of this embodiment, similar to the conventional fluid-filled engine mount, engine shake etc. It is possible to satisfactorily attenuate large-amplitude vibrations in a low-frequency range such as muffled sounds, etc., and also dampen small-amplitude vibrations in a relatively high frequency range such as muffled sounds based on the liquid column resonance of the incompressible fluid caused by the deformation of the thin wall portion 46 of the partition member 36. In addition to being able to effectively isolate vibrations, based on the deformation of the dish-shaped portion 58 of the rubber elastic body 26, it is also possible to effectively isolate small amplitude vibrations in a high frequency range such as engine transmitted sound. It is possible to obtain better vibration isolation characteristics against input vibrations in a wider frequency range than with type engine mounts.

Further, in the engine mount of this embodiment, as described above, when vibration is input in the main vibration input direction, the dish-shaped portion 58, which is the second deformed portion of the rubber elastic body 26, is rotated at its tapered cylindrical outer peripheral portion. Since the rubber elastic body 26 is mainly subjected to shear deformation, the main vibration input of the rubber elastic body 26 is smaller than when a structure is adopted in which the second deformation portion of the rubber elastic body 26 is compressively deformed exclusively in the main vibration input direction. In addition, the dimensions in the main vibration input direction of the engine mount can be kept sufficiently small, and as mentioned above, the wall thickness or cross-section of the tapered cylindrical outer circumference, which is the shear deformation part of the dish-shaped part 58, can be kept small. The area can be set sufficiently large, and the durability of the rubber elastic body 26 can be improved while making the engine mount more compact.

One embodiment of the present invention has been described in detail above, but
This is a literal example, and it goes without saying that the present invention should not be construed as being limited to this specific example.

For example, in the embodiment described above, the dish-shaped part 60, which is the first deformed part, and the dish-shaped part 58, which is the second deformed part, of the rubber elastic body 26 are made of the same rubber material. It is also possible to configure it with different rubber materials.

Further, in the embodiment described above, the partition member 36 is made of an elastic material, and the center portion thereof is formed of a thin wall portion 4.
6, and the thin wall portion 46 was given the function of a movable means, but such a movable means does not necessarily need to be provided. Even without providing such a movable means, the effects of the present invention can be enjoyed.

Furthermore, in the above embodiment, an example was described in which the present invention was applied to an engine mount for a front-wheel drive vehicle.
The present invention can also be applied to mount devices other than such engine mounts for FF vehicles.

In addition, although it is omitted to list specific examples one by one, within the scope of the present invention without departing from the spirit of the invention,
Various modifications based on the knowledge of those skilled in the art,
Things that can be implemented with modifications, improvements, etc. are:
It goes without saying.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of an engine mount for a front-wheel drive vehicle according to the present invention. 10...First support fitting (first support), 1
2...Second support fitting (second support), 26...
... Rubber elastic body, 32 ... Diaphragm (flexible membrane; partition member), 36 ... Partition member, 38 ... Pressure receiving chamber, 40 ... Equilibrium chamber, 42 ... Throttle passage, 58
... dish-shaped part (second deformed part), 60... dish-shaped part (first deformed part).

Claims (1)

[Claims for Utility Model Registration] (a) first and second supports disposed at a predetermined distance in the main vibration input direction, and (b) the first support and the second support. and (c) a rubber elastic body disposed on the second support side and partially defined by the rubber elastic body. (d) a predetermined incompressible fluid sealed in the fluid accommodation space; A fluid-filled mount comprising: a partition member that partitions a space into a pressure receiving chamber on the rubber elastic body side and an equilibrium chamber on the partition wall member side; and (f) a throttle passage that allows the pressure receiving chamber and the equilibrium chamber to communicate with each other. In the apparatus, the rubber elastic body is arranged between an inwardly facing dish-shaped first deformable portion defining the fluid accommodation space and an outwardly facing dish-like deformed portion between the first deformable portion and the first support body. and a second deformable portion are connected back to back to form an integrally formed substantially X-shaped cross-sectional structure, and the static spring constant of the second deformable portion in the main vibration input direction is changed from that of the first deformed portion. While setting it larger than that of the section,
A fluid-filled mount device characterized in that the second deformable portion of the rubber elastic body is structured to undergo shearing deformation mainly in the main vibration input direction.