JPS628162Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to the insulation structure of an automobile suspension, and in particular, the invention is concerned with the insulation structure consisting of an elastic body such as rubber and an oil damper. The present invention relates to an insulation structure for an automobile suspension that has a good vibration isolation effect against a wide range of vibrations ranging from low-frequency vibrations related to driving performance to high-frequency vibrations related to noise.

[Conventional technology]

A conventional automobile suspension insulation (such as that disclosed in Japanese Utility Model Application Publication No. 57-74804) is provided as shown in FIG. In the figure, 1 is a vehicle body, and 2 is a rod connected to wheels (not shown) and a strut to support the vehicle body 1. An insulation 3 is interposed between the rod 2 and the vehicle body 1. The insulation 3 consists of mounting brackets 4 and 5 that are attached to the vehicle body 1 and the rod 2, respectively, and a rubber elastic body 6 that is provided to connect these mounting brackets 4 and 5. The vibration transmitted to the vehicle body 1 via the rod 2 is insulated by the elastic body 6 of the insulation 3.

However, when using the insulation 3 of the elastic body 6 as described above, the frequency dependence of the displacement transmissibility becomes as shown by curve a in FIG.
Although the vibration insulating effect against high frequency vibrations is large and the soundproofing properties are excellent, a resonance point f ₀ appears at low frequencies, making it impossible to sufficiently prevent body shake.

In order to prevent this body shake, the height of the rubber of the elastic body 6 of the insulation 3 is increased to increase its spring constant, or the material of the rubber is changed so that the spring constant is the same but the damping performance is increased. There are ways to change it.

[Problem that the invention attempts to solve]

However, when these methods are adopted, vibration isolation properties in high frequency ranges (noise) deteriorate. In other words, when the spring constant is increased, the displacement transmissibility becomes
Curve b in the figure results in better vibration isolation at low frequencies, but a resonance point occurs on the high frequency side. Furthermore, if the material of the rubber is changed to increase the damping force, the displacement transmissibility becomes curve C, which similarly deteriorates the vibration isolation characteristics on the high frequency side.

For this purpose, the insulation should be made of a combination of rubber and a spring, for example, so that its spring constant changes stepwise or continuously in response to changes in load, that is, it has a nonlinear spring constant. A method is proposed. With this method, road vibrations (low-frequency, large-amplitude vibrations), etc.
Increase the spring constant to reduce the vibration displacement,
The idea is to reduce the spring constant to deal with sound (high-frequency, small-amplitude vibrations).

However, this method cannot prevent small amplitude bodyshake in the low frequency range, and if measures against bodyshake are taken, noise isolation becomes insufficient.

The present invention has been devised to effectively solve the above-mentioned conventional problems.

The purpose of the present invention is that the insulation is composed of an elastic body such as rubber for absorbing high frequencies and an oil damper for absorbing low frequencies.
To provide an insulation structure for an automobile suspension capable of sufficiently blocking vibrations transmitted from wheels to a vehicle body over a wide range of frequencies from low frequencies to high frequencies.

[Means for solving problems]

The present invention is an insulation structure that is provided between a rod connected to a wheel and the vehicle body to prevent vibrations from the wheel. It has an elastic body, a first hydraulic chamber whose partition wall is a part of the elastic body, and a second hydraulic chamber that communicates with the first hydraulic chamber via an orifice and is divided by a diaphragm. It is equipped with an oil damper.

[Effect]

Of the vibrations transmitted from the wheels, low-frequency vibrations such as road vibrations deform the elastic body, and the deformation of the elastic body causes oil to move between the first and second hydraulic chambers through the orifice. Vibration in the low frequency range is attenuated by the oil friction at that time. Further, vibrations in a high frequency range are blocked by the elastic body.

〔Example〕

An embodiment of the present invention will be described below.

In Fig. 3, 1 is the car body, 2 is the car body 1
It is a rod connected to the wheel via a strut to support it. A spring receiver 8 for fixing the suspension spring 7 is provided on the upper part of the rod 2. An elastic body 9 made of synthetic rubber is provided between the spring receiver 8 and the vehicle body 1, and a mounting seat 10 at the upper end of the elastic body 9 is attached to the vehicle body 1 with a bolt 11.

An orifice plate 12 is provided above the elastic body 9 and is fitted into the end of the mounting seat 10 so as to cover the upper surface of the elastic body 9. 1 hydraulic chamber 13
is formed. Further, a diaphragm 14 is provided on the orifice plate 12, and a second hydraulic chamber 15 is formed in a fluid-tight manner by partitioning the diaphragm 14. The first hydraulic chamber 13 and the second hydraulic chamber 15 are filled with oil O, and the orifice 1 of the orifice plate 12
Oil O can be moved between the first and second hydraulic chambers 13 and 15 via the hydraulic pressure chamber 6, and an oil damper 17 is formed.

Next, the operation of the above embodiment will be described.

Vibration from the wheels is transmitted to the rod 2, and from the rod 2 to the elastic body 9 via the spring receiver 8, causing the elastic body 9 to vibrate. Large vibrations in the low frequency range are absorbed as follows. The elastic body 9 is greatly deformed by the large vibration, and this deformation causes the oil O to move between the first and second hydraulic chambers 13 and 15 through the orifice 16. The vibration energy of the elastic body 9 is absorbed by fluid friction when the oil O passes through the orifice 16, and the vibration of the elastic body 9 is attenuated. In this way, vibrations in the low frequency range are attenuated by the damping force of the oil damper 17, and the peak at the resonance point in the low frequency range is removed.

Furthermore, in response to vibrations in the high frequency range, the oil damper 17 cannot follow the fast vibrations of the elastic body 9, and almost no oil O can pass through the orifice 16, and the oil damper 17 becomes a rigid body in the high frequency range. Damping force does not work. In the high frequency range, the elastic body 9 vibrates as shown by the chain line in FIG. 3, thereby absorbing vibrations from the rod 2. Furthermore, as mentioned above, in the low frequency range, the oil damper 17
Since vibrations are well damped by this, the hardness of the rubber of the elastic body 9 can be reduced, and the vibration isolation effect in the high frequency range can be improved.

In this way, the insulation of the present invention has a good vibration isolation effect over a wide range from low frequency range to high frequency range, and ultimately achieves excellent vibration isolation characteristics as shown by curve d in Figure 2. be able to.

In the above embodiment, the orifice 16 is always open, but a movable orifice 18 as shown in FIG. 4 may also be used. The movable orifice 18 is sandwiched between an orifice plate 19 that hangs down from the diaphragm 14 and partitions the first hydraulic chamber 13 and the second hydraulic chamber 15, and the periphery of the orifice plate 19 to restrict the movement of the orifice plate 19 within a predetermined range. The stopper 20 has a groove 20a. Movable orifice 18
The elastic body 9 is greatly deformed due to vibration and the oil O
When the orifice plate 19 moves due to the flow etc. and comes into contact with the stopper 20, the orifice plate 19 is closed, and the first and second hydraulic chambers 13,
The flow path between 15 and 15 is cut off, and the response is relatively good even to high-frequency vibrations.

In the above embodiment, the shape of the oil damper 17 may be changed in any way, and its mounting position is not limited to above the elastic body 9, but may also be provided below it, or may be installed in series between the rod 2 and the vehicle body 1. It may also be set in Furthermore, the elastic body 9 may be made of not only rubber but also a combination of rubber and a spring.

[Effect of idea]

As is clear from the above description, according to the present invention, the following excellent effects can be achieved.

Low-frequency vibrations can be attenuated and absorbed by the oil damper, and high-frequency vibrations can be absorbed by an elastic body such as rubber, making it possible to obtain a good vibration isolation effect against vibrations in a wide frequency range.

Since vibrations in the low frequency range can be damped by the oil damper, a soft rubber or the like with low hardness can be used as the elastic body, and the vibration isolation effect in the high frequency range can be further enhanced.

Moreover, it has a simple structure, can be produced at low cost, and is highly useful.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view of a conventional insulator, Fig. 2 is a graph showing the frequency dependence of the displacement transmissibility of the insulator, and Fig. 3 is an implementation of the insulator according to the present invention. FIG. 4 is a side sectional view showing another embodiment of the present invention. In the figure, 1 is the vehicle body, 2 is a rod, 9 is an elastic body such as rubber, 13 is a first hydraulic chamber, 14 is a diaphragm, 15 is a second hydraulic chamber, 16 and 18 are orifices (18 is a movable orifice) , 17 is an oil damper.

Claims (1)

[Scope of utility model registration request] An insulation structure for an automobile suspension provided between a rod connected to a wheel and a vehicle body to prevent vibrations from the wheel, comprising: an elastic body such as rubber interposed between the rod and the vehicle body; and an oil damper having a first hydraulic chamber with a part of the elastic body as its partition wall, and a second hydraulic chamber connected to the first hydraulic chamber via an orifice and partitioned by a diaphragm, wherein high frequency vibrations from the wheel are absorbed by the elastic body and low frequency vibrations are absorbed by the oil damper.