JPS61233237A - Liquid attenuation type vibrationproof supporting device - Google Patents

Abstract

PURPOSE:To effectively attenuate the low frequency vibration and effectively cut off the transmission of high frequency vibration by expanding and contracting a fluid bag installed in close contact with a partitioning plate according to the vibration frequency. CONSTITUTION:The chamber charged with fluid is divided into chambers 12 and 13 by a partitioning plate 6, and a fluid bag 14 is attached onto one side surface of the partitioning plate 6. A fluid pressure generator 15 for varying the capacity of the bag is connected with the fluid bag through a pipe 17, and detects the frequency of the vibration of a vibration body and generates the pulsation pressure having the reverse phase in case of low frequency vibration having the equal frequency to the detected frequency and generates the pulsation pressure in the equal phase in case of high frequency vibration.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a liquid damping vibration damping support device used to support a vibrating body such as an automobile engine in a vibration damping manner.

(Prior art) When supporting an engine installed in an automobile in a vibration-proof manner, the engine's rotational speed fluctuates greatly, so the damping coefficient for large-amplitude low-frequency vibrations that occur at low speeds is large; There is a need for a vibration-isolating support device that can satisfy the two requirements of high vibration insulation against high-frequency vibrations that sometimes occur, but it also has high vibration isolation properties against low-frequency vibrations such as cranking vibrations and idling vibrations, and medium-frequency vibrations. Noise caused by high-frequency vibrations, such as muffled sound and transmitted sound, have characteristics that conflict with each other, so it is difficult to effectively and simultaneously exhibit vibration damping performance for both types of noise.However, recently, vibration damping functions have been included. A liquid damping type vibration isolating support device is adopted in which the vibration isolating function can be supported by a vibration isolating base material made of rubber or elastic material that forms a chamber wall for sealing the liquid. It's starting to look like this.

By the way, in the conventional anti-vibration support device of this type, an inner chamber provided in a main body having an anti-vibration base material made of a rubber cylindrical body is divided into two by a partition plate.
This is a well-known structure that is divided into two chambers, these spaces are communicated through an orifice provided in the partition plate, and a liquid is sealed in each chamber. Most of them are fixed to the inner wall of the main body.

On the other hand, a structure in which the partition plate has a thin structure to easily absorb small-amplitude vibrations in a high frequency range has also been proposed and used in some cases.

(Problems to be Solved by the Invention) In the former of the above-mentioned conventional devices, since the partition plate has a high rigidity and a fixed structure, the liquid pressure in the liquid chamber increases in the high frequency vibration region, causing the movement of the spring. The problem is that the constant becomes large, which causes a muffled sound and impairs the quietness of the vehicle interior.

On the other hand, the latter has the disadvantage that the damping characteristics against vibrations in the medium and low frequency ranges deteriorates, and it is difficult to manufacture partition plates with a thin film structure that have uniform thickness and uniform mechanical strength and characteristics. It had

Therefore, the technical object of the present invention is to solve the drawbacks of the conventional devices of this type.
In order to exhibit damping performance against low-frequency vibrations, a fluid bag attached to one side of a rigid partition plate is expanded synchronously in an opposite phase to the vibrations propagating from the vibrating body. On the other hand, by synchronously expanding and contracting the fluid bag in the same phase in order to reduce the dynamic spring constant against high frequency vibrations, it not only damps low frequency vibrations, but also reduces the fluid pressure caused by high frequency vibrations. The idea is to suppress the rise in noise and eliminate particularly muffled noise, thereby playing a role in realizing lower vibration and noise in automobiles.

(Means for Solving the Problems) Accordingly, the present invention combines a liquid damping type vibration isolating support device (hereinafter referred to as a vibration isolating mount) with a vibration isolating support and a fluid pressure generating device.
The vibration isolating support is provided in a main body (1) having a vibration isolating base (2) made of a rubber elastic body, and has an orifice (
The chambers (6) and (13) are partitioned by a partition plate (6) made of a rigid plate provided with a partition plate (16), and the chambers (13) are attached to at least one side of the partition plate (6) to prevent a change in volume. The structure is such that a possible fluid bag (14) is provided.

Further, the fluid pressure generating device (a) detects the vibration frequency of the vibrating body supported by the vibration isolating support, and when the vibration frequency is the same as this and the vibration frequency is in a low frequency range, The device is designed to generate pulsating pressures in the same phase when in the high frequency range.

The present invention is characterized in that the fluid pressure generating device αQ and the fluid bag α◆ are connected by a pipe aη.

(Function) The present invention has the above-mentioned means, so that when a supported vibrating body such as an engine vibrates, the main body (
Since the rubber elastic body that is the vibration-proof base (2) of 1) receives dynamic compressive deflection, the chambers (2) on both sides of the partition plate (6), α
The field changes volume reversibly.

In this case, the vibration of the anti-vibration support, which is a low-frequency vibration, and the fluid bag α→ have an opposite phase relationship, and while the chamber in which the fluid bag α◆ resides tends to expand or contract, the fluid bag α
→ conversely contracts or expands, resulting in orifice cA
Liquid movement occurs through Q, and naturally many liquid movements occur in the forward and reverse directions in response to vibrations, and at this time, the damping function due to the aperture effect is fully exerted, making it possible to effectively dampen low-frequency vibrations. .

On the other hand, in response to the occurrence of high-frequency vibrations, the fluid pressure in the chamber tends to rise, but since the fluid bag α→ expands and contracts in the same phase as the volume change in the chamber, the increase in fluid pressure is reduced. ,
The dynamic spring constant on the high frequency vibration region side can be reduced, and vibration transmission can be effectively blocked.

(Example) Hereinafter, an example of the present invention will be described based on the accompanying drawings.

The illustrated anti-vibration mount is composed of an anti-vibration support and a fluid pressure generating device (1), and the anti-vibration support is connected to the main body (1).
), a first metal fitting (3), a second metal fitting (4), a rubber plate (5), and a partition plate (6) as main constituent members.

The main body (1) has a metal cylindrical body (7) on one side of a block-shaped rubber elastic body that serves as a vibration-proof base (2), and a mounting bolt (9) on the other side fitted in the center. flat metal plate (8)
are attached together during the vulcanization molding process.

The first metal fitting (3) has a hat shape and has a mounting bolt (10) fitted in the center, and its peripheral portion is covered with the end of the cylindrical body (7) in the main body (1). After crowning
The first metal fitting (3) is fixed and integrated with the main body (1) by caulking.The first metal fitting (3) has a small hole (Xη) bored at an appropriate location such as the side to form an air circulation hole.

The second metal fitting (4) is a metal plate having an abbreviated shape, and is brought into contact with the vibration isolating base (2) from any direction and is brought into surface contact with the metal flat plate (8). After inserting the bolt (9), it is fixed and integrated with the main body (1) by tightening.

On the other hand, the rubber plate (5) is a cylindrical body (
7) is placed horizontally so as to cover the open end, and its peripheral edge is held between the end of the cylindrical body (7) and the peripheral edge of the first metal fitting (3). It is fixed to the main body (1) in an airtight manner.

The vibration-proof support constructed in this manner has the inner surface of the vibration-proof base (2), the inner wall surface of the cylindrical body (7), and the rubber plate (5) in the main body (1).
) is formed with an inner chamber having a sealed structure with one side as a peripheral wall, and a partition plate (6) is installed horizontally in this inner chamber, and this partition plate (6) allows the inner chamber to be opened up and down. It is divided into two rooms (to) and (to).

The partition plate (6) is made of a rigid plate made of hard synthetic resin or the like, and has a thick peripheral edge and a thin flat plate part surrounded by the peripheral edge. A groove (lI→) extending in the circumferential direction over substantially the entire circumference is recessed in the groove, and this groove αO is divided by at least one swash plate portion (1) to form an arc-shaped passage extending substantially around the entire circumference. None, there is a communication hole (end) that passes through the periphery from one end and faces the chamber, and a communication hole α that also passes through the periphery from the other end and faces the chamber. (See Figures 2 and 3).

The partition plate (6) having such a structure is fixed to the inner circumferential wall of the main body (1), for example, to the inner circumferential wall of the metal cylindrical body (7) by pressure fitting. The groove α· serves as a passage communicating between the compartments (6) and (to), and is thus formed as an orifice through which fluid flows reversibly.

A fluid bag (14) whose volume can be changed is attached to the lower or upper surface of the partition plate (6) and fixed as appropriate. It is formed into a flat, airtight, flexible bag with a pipe connection port opened at one location.

The fluid pressure generating device a0, which is paired with the vibration isolating support having the above-mentioned structure, is a device that generates pulsating pressure in a manner that can increase or decrease the frequency, and the fluid pressure generating device a0, which is paired with the vibration isolating support having the above-mentioned structure, is a device that generates pulsating pressure so that the frequency can be increased or decreased. It has a structure that can detect the vibration frequency of the engine with a vibration meter or the like and generate fluid pressure with pulsations at the same frequency. For example, when the frequency is below 45 Hz, air pressure with the opposite phase (meaning a phase angle shift of 1800) is generated relative to the vibration of the vibrating body, and when the frequency is in a high frequency range exceeding 45 Hz, fluid pressure with the same phase is generated. It is formed so that it occurs.

Then, the pressure fluid supply port of this fluid pressure generating device (to) and the pipe connection port of the fluid bag α→ are connected by a pipe αη.

The device example of the present invention has the structure described above, but the vibration isolating support has a liquid such as antifreeze sealed in each chamber (a) and a3, and further includes a fluid pressure generating device (to) and a fluid bag αΦ as described above. The vibration isolating support is used as a vibration isolator between the body and the engine of an automobile, for example, by connecting them with a pipe αη.

In this case, high-frequency vibrations generated during running are basically absorbed by the vibration-proof base (2), so muffled sound and transmitted sound can be well absorbed and blocked.

On the other hand, low frequency vibrations such as idling vibrations
3 is effectively damped by reversibly flowing the liquid through the orifice αQ.

By the way, when low frequency vibration occurs, as shown in Fig. 4, the fluid bag α→ expands and contracts due to the pulsating pressure of opposite phase and equal frequency, so as explained in the section of the above action. As a result of the conspicuous throttling effect of the orifice αQ, the damping coefficient against vibration becomes large, and low frequency vibrations can be effectively damped by the vibration isolating support.

On the other hand, when high-frequency vibration occurs, the fluid bag α◆ expands and contracts due to pulsating pressure of the same phase and frequency, as shown in Fig. This reduces the dynamic spring constant and effectively blocks vibration transmission.

(Effect of the invention) As described above, according to the present invention, the partition plate (6
), the fluid bag α◆, which is placed in close proximity to the
By contracting, the fluid chamber containing this fluid bag α→ expands,
While it operates in opposition to contraction, when high-frequency vibrations occur, it expands and contracts in synchronization with the expansion and contraction of the liquid chamber, so in the high-frequency vibration region, the increase in liquid pressure is suppressed, and the , the dynamic spring constant can be made small, and it has excellent blocking properties for muffled sound and transmitted sound.
On the other hand, in the low-frequency vibration region, the orifice 0Q exerts a throttling effect even more, achieving effective vibration damping.

In this way, it is possible to stably exhibit sufficient blocking performance against vibrations in a wide range of areas including low and high frequencies.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional structural diagram of a main part according to an example of the present invention, FIG. 2 is a plan view of the partition plate in FIG. 1, FIG. 8 is a cross-sectional view taken along the line A-A in FIG. 2, and FIG. and FIG. 5 is a vibration characteristic diagram showing the relationship between the vibration of the fluid bag and the vibration of the vibrating body in FIG. 1 in a low frequency range and a high frequency range, respectively. (1)...Main body, (2)...Vibration isolation base,
(6)... Partition plate, (6), Q3... Room,
α◆...Fluid bag, (to)...Fluid pressure generator, α...Orifice, αη...Pipe. Figure 1 Figure 4 Figure 5

Claims (1)

[Claims] 1. Main body (
The inner chamber provided in 1) and filled with fluid is divided into two chambers (12) and (13) by a partition plate (6) made of a rigid plate provided with an orifice (16) passing through the thickness direction. A vibration-proofing support comprising a fluid bag (14) whose volume can be changed by being partitioned and attached to one side of the partition plate (6), and a vibration-proofing support supported by this vibration-proofing support. a fluid pressure generator (15) that detects the vibration frequency of the body and generates pulsating pressure at the same frequency and in opposite phase when the vibration frequency is in a low frequency range and in the same phase when the vibration frequency is in a high frequency range; The fluid pressure generating device (15) and the fluid bag (14)
A liquid damping type vibration isolating support device, characterized in that the two are connected by a pipe (17).