JPS6327590B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention has a small dynamic spring constant for high-frequency vibrations that occur when driving at high speeds or acceleration in automobiles, etc., and a large damping coefficient for low-frequency vibrations that occur when driving at low speeds. The present invention relates to a rubber bearing device with liquid damping function that has ideal spring characteristics.

When a vibration-producing device such as an automobile engine is elastically supported by vibration-proof rubber, a resonance phenomenon occurs when the device is started or stopped, or due to excitation having a frequency component near the natural frequency of the support system. The excessive amplitude caused by this often causes various troubles.

Particularly when supporting an engine installed in a car in a vibration-proof manner, since the rotational speed of the engine varies widely, it is necessary to have a large damping coefficient for low-frequency vibrations with large amplitudes at low speeds, and high-frequency vibrations at high speeds. Of course, a bearing device that satisfies the two requirements of high vibration isolation is required, but a bearing device that uses rubber or air springs, which are high damping materials, as an element has a high damping property against low frequency vibrations. If the function is increased, the dynamic spring characteristics against high-frequency vibrations will increase, and conversely, if the dynamic spring characteristics against high-frequency vibrations are made good, the damping function against low-frequency vibrations will no longer be exhibited, and the dynamic spring characteristics against high-frequency vibrations will not be effective against vibrations in a wide range. It is well known that this device has the drawback of not being able to maintain effective vibration damping performance.

In an attempt to eliminate such drawbacks, a bearing device with a structure as shown in Fig. 2 has already been provided as a bearing device that exhibits satisfactory vibration isolation characteristics for both high and low frequency vibrations, and the present applicant has For example, as previously proposed in Japanese Patent Application No. 55-141193, this type of rubber bearing device is fixed to a vibration generator, as is clear from Fig. 2. A member integrally formed of the housing member 4, the rubber cylindrical body 3, and the rubber elastic plate 11 is connected between the upper metal fitting 1 for fixing to the frame and the lower metal fitting 2 for fixing to the frame. A sealed space surrounded by the shaped body 3, the housing member 4, and the rubber elastic plate 11 is partitioned into two upper and lower chambers by a fixed partition 10 in which an orifice member 8' is interposed. It has a structure in which liquid is sealed in both the upper and lower chambers, which are communicated through the chamber.

The space surrounded by the rubber elastic plate 11 and the lower metal fitting 2 can be formed as either a sealed space containing air or an open space communicating with the atmosphere.

In the rubber bearing device having the above structure, when a vibration generator such as an engine vibrates, the rubber cylindrical body 3 receives dynamic compressive deflection via the upper metal fitting 1.
The volume of the upper chamber changes.

Due to this change in volume in the upper chamber, the enclosed liquid flows into the lower chamber through the orifice member 8' and vice versa, resulting in a throttling effect on the liquid passing through the orifice member 8'. Therefore, it is possible to obtain a high damping ability against vibrations, and thus it is possible to provide a rubber bearing device that can exhibit the desired vibration damping performance.

Although the above-mentioned support device has the above-mentioned advantages, since it has a structure with two fluid chambers in the upper and lower directions, it has a problem that the height dimension becomes large and the installation space is considerably large. In addition, the large height increases the amplitude during vibration, which is disadvantageous.

Furthermore, if the rubber elastic plate 11 is damaged, the liquid will leak outside and not only will it completely lose its anti-vibration performance, but it will also lose its ability to carry heavy objects, so it must be immediately replaced with a new one. Must.

In view of the fact that conventional rubber bearing devices still have problems that need to be improved, the present invention provides an orifice which is a member capable of damping low frequency vibrations especially during low speed operation. By encapsulating the structure of the part that changes the chamber volume in relation to the members and sealing it in a liquid-filled chamber with high mechanical strength, the height dimension can be reduced and compactness achieved. This has achieved the desired purpose of not only lowering the dynamic spring constant but also creating a robust device that does not cause liquid leakage. A rubber cylindrical body whose upper part is hermetically connected to an upper metal fitting and whose lower part is hermetically connected to a lower metal fitting, and a capsule housed in a closed space surrounded by the rubber cylindrical body and both the upper and lower metal fittings. The capsule has a double-chamber structure in which a sealed bag that can be expanded and contracted is housed within a rigid case, and the sealed bag is sealed via an orifice member provided by passing through the rigid case. The airtight bag is characterized in that the airtight bag is in communication with a space, and the airtight space and the airtight bag are filled with liquid.

Hereinafter, in order to clarify the specific contents of the apparatus of the present invention, a detailed description will be given based on an example shown in the accompanying drawings.

FIG. 1 is a schematic structural diagram of an example of the rubber bearing device of the present invention, which includes an upper metal fitting 1 for fixing to the body of an automobile engine, a lower fitting 2 for fixing to the automobile body, and a rubber tube. It includes a shaped body 3, a housing member 4, and a capsule 5 as constituent members.

The rubber cylindrical body 3 is in the shape of a pot with an open bottom, and its top is integrally fixed to the upper metal fitting 1, and its bottom periphery is integrally fixed to a housing member 4 having an annular shape.

The connections made between the upper metal fitting 1 and the rubber cylindrical body 3 and between the housing member 4 and the rubber cylindrical body 3 are completely liquid-tight and have sufficient durability against external mechanical forces. vulcanization adhesion is a suitable treatment means.

On the other hand, the housing member 4 serves as a reinforcing member for the rubber cylindrical body 3, and also functions as a supporting base material for the rubber cylindrical body 3 by being closely integrated with the lower metal fitting 2.

By thus integrating the lower fitting 2 and the housing member 4 in a fluid-tight manner, a liquid-tight sealed space surrounded by the upper fitting 1, the lower fitting 2, the rubber cylindrical body 3, and the housing member 4 is created. The sealed space is filled with a liquid 9 such as water.

Next, the capsule 5 has a double chamber in which an expandable and contractible sealed bag 7 made of an elastic material such as rubber is housed in a liquid-tight rigid case 6 made of a rigid plate such as hard synthetic resin or metal. The inside of the sealed bag 7 is communicated with the sealed space outside the rigid case 6 through an orifice member 8, for example, a thin tube, which is provided through the rigid case 6.

The space existing between the rigid case 6 and the sealed bag 7 of the capsule 5 has an appropriate volume corresponding to the volume of the sealed space filled with the liquid 9, and is filled with air at atmospheric pressure or higher pressure. is included.

Then, the capsule 5 is allowed to float in the liquid in the sealed space or is attached to one location of the rubber cylindrical body 3 (not shown).

The rubber bearing device having the configuration described above is surrounded on the outside by the sturdy members of the upper metal fitting 1, the lower metal fitting 2, the housing member 4, and the strong rubber cylindrical body 3 made of thick rubber or the like. The mechanical strength is almost never significantly damaged by external forces.

When a vibration generator such as an engine is supported, the pressure applied to the sealed space and the capsule 5
The sealed bag 7 maintains its regular shape when the pressure of the sealed air portion is balanced.

When the engine is running and vibrates, the rubber cylindrical body 3
When subjected to dynamic compressive deflection, it exhibits dynamic spring characteristics and functions as a vibration damper.

At this time, the volume of the portion filled with liquid 9 inside the cylindrical body 3 changes due to the bending of the rubber cylindrical body 3, so that the liquid 9 moves in and out of the sealed bag 7 via the orifice member 8.

Therefore, the squeezing effect of the liquid passing through the orifice member 8 provides a high vibration damping ability, which is a characteristic comparable to the conventional support device illustrated in FIG.

However, since the volume inside the sealed bag 7 fluctuates depending on the inflow and outflow of the liquid 9, the lever support device
The main difference is that the wall of the rigid case 6 is movable relative to the corresponding fixed partition 10 in FIG. By the way, by forming a movable partition in this way, a large damping coefficient can be obtained.

By the way, even if the sealed bag 7 should be damaged during use, the rubber support device will
The sealed air between the housing 6 and the rigid case 6 simply moves into the rubber cylindrical body 3, and there is no problem such as leakage of the liquid 9 to the outside of the device, so no damping performance can be expected in such a case. It has the advantage of being able to maintain its ability to carry heavy objects.

Next, the unique effects of the device of the present invention are as follows.

(b) Both the upper and lower fittings 1 are encapsulated with a structure that has a damping function against vibrations, especially low frequency vibrations.
2 and a rubber cylindrical body 3, making it possible to obtain a device that is strong against external forces and has a long life, while also having a lower height compared to conventional devices with an upper and lower two-chamber structure. It can be made into a compact structure.

(b) Manufacturing is extremely simple because the product is completed by making the capsule 5 separately in advance, storing it in the rubber cylindrical body 3, and then filling it with liquid.

(c) Even if the sealed bag 6 of the capsule 5 were to be damaged during use, the attenuation function would simply be lost and the loading capacity could be ensured without any leakage of the liquid 9. , the reliability is higher than that of conventional devices in which liquid leakage occurs due to damage to the rubber elastic plate 11, which necessitates replacement.

As described above, the present invention is a rubber bearing device that is of great practical value and has many benefits to the field.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of a rubber bearing device of the present invention, and FIG. 2 is a schematic sectional view of a conventional rubber bearing device. DESCRIPTION OF SYMBOLS 1... Upper metal fitting, 2... Lower metal fitting, 3... Rubber cylindrical body, 4... Housing member, 5... Capsule, 6
... Rigid case, 7 ... Sealed bag, 8 ... Orifice member.

Claims (1)

[Claims] 1. An upper metal fitting, a lower metal fitting, a rubber cylindrical body interposed between the two metal fittings, the upper part of which is airtightly connected to the upper metal fitting, and the lower part of which is airtightly connected to the lower metal fitting, and the rubber cylindrical body and both the upper and lower metal fittings. The capsule is housed in a sealed space surrounded by metal fittings, and the capsule has a double-chamber structure in which a sealed bag that can be expanded and contracted is housed in a rigid case, and the inside of the sealed bag is surrounded by the rigid case. A rubber bearing device having a liquid damping function, characterized in that the device communicates with the sealed space through an orifice member provided through the case, and the sealed space and the sealed bag are filled with liquid.