JPS62113933A - Vibration control equipment - Google Patents

Abstract

PURPOSE:To effectively prevent an increase in dynamic spring constant of a vibration control equipment for high-frequency small amplitude vibration by forming a subsidiary liquid chamber on a partition wall for dividing into two liquid chambers, dividing an adjacent portion to both liquid chambers by a flexible film. CONSTITUTION:An incompressible liquid such as water is enclosed in the whole of a closed chamber 11, and the chamber is divided into two liquid chambers 13, 14 by a partition wall 12 provided wit a throttle passage 15. A subsidiary liquid chamber 21 where a required liquid is enclosed is formed by rubber films 17, 18 adjacent to the liquid chambers 13, 14. In this arrangement, vibration transmitted to a frame 2 is, if it has low-frequency and large amplitude, damped by internal friction of an elastic member 3 and fluid resistance and liquid column resonance of a liquid passing the throttle passage 15. On the other hand, high-frequency small amplitude vibration is insulated by deformation of the rubber films 17, 18. Accordingly, such vibration having contrary characteristics can be effectively damped and insulated to prevent an increase in dynamic spring constant effectively.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is applicable to automobiles and other vehicles, mechanical equipment, etc., and provides sufficient attenuation of low-frequency, large-amplitude vibrations, as well as advantageous insulation of high-frequency, small-amplitude vibrations. The present invention relates to a vibration isolating device that provides the following.

(Prior Art) For example, in a conventionally known vibration isolator that is widely used as an engine mount for automobiles, between a frame body connected to the vehicle body and a frame body connected to the engine,
An elastic member that contributes to the formation of a sealed chamber is arranged, water or other incompressible liquid is sealed in the sealed chamber, and this sealed chamber is separated by a partition wall whose peripheral edge is fixed to one frame. Some liquid chambers are divided into two liquid chambers, and these two liquid chambers are connected by a passage provided in a partition wall.

Such a vibration isolator reduces the flow resistance that the liquid receives from the passage when the liquid in one liquid chamber flows into the other liquid chamber through the passage when vibrations from the engine are transmitted thereto. Vibration damping can be provided by its own viscous resistance, internal friction of the elastic member, etc.

(Problems to be Solved by the Invention) However, in this vibration isolator, when the vibration transmitted thereto is a high frequency, small amplitude vibration of 50 It z or more, for example, the viscous force and inertial force of the liquid, The communication passage becomes blocked due to frictional force between the liquid and the communication passage, and as a result, the dynamic spring constant of the device rapidly increases, resulting in a significant deterioration of the ride comfort of the vehicle. There was a problem.

The present invention advantageously solves the problems of the prior art, and provides a vibration isolator that can extremely effectively exhibit contradictory characteristics of attenuating low-frequency, large-amplitude vibrations and insulating high-frequency, small-amplitude vibrations. It is something.

(Means for Solving the Problems) Here, the present invention disposes an elastic member that is in close contact with two frame members that are connected to different members and contributes to forming a sealed chamber, and Water or other incompressible liquid is sealed in the sealed chamber, this sealed chamber is divided into two liquid chambers by a partition wall whose peripheral edge is fixed to one frame, and these two liquid chambers are divided into two liquid chambers. In a vibration isolating device that communicates with each other by at least a passage provided in a partition wall or the like, a sub-liquid chamber is formed in the partition wall, and the sub-liquid chamber is filled with a liquid of the same type or a different type from the liquid in both of the liquid chambers. The adjacent portions of the liquid chambers are partitioned by a flexible membrane.

(Function) In this vibration isolator, when a low frequency large amplitude vibration is transmitted to the vibration isolation device, when the liquid in the high pressure side liquid chamber flows through the passage into the low pressure side liquid chamber, the main effect is as follows. The flow resistance experienced by the liquid from the passageway and the liquid column resonance provide effective damping of vibrations.

Furthermore, when high-frequency, small-amplitude vibrations are transmitted to this device, the deformation of both flexible membranes based on the pressure difference between the pressures in both liquid chambers when the passage is closed, or in other words, the high pressure in the auxiliary liquid chamber. The displacement from the side to the low voltage side results in sufficient isolation of the vibrations.

(Example) The present invention will be explained below based on illustrated examples.

FIG. 1 is a cross-sectional view showing one embodiment of the present invention, in which 1 indicates one member, for example a frame connected to an automobile body, and 2 indicates the other member, for example a frame connected to an engine. , and 3 indicates an elastic member which is disposed between these two frames 1.2 in close contact therewith and contributes to the formation of a sealed chamber to be described later.

Here, one frame 1 is attached to a flange 5a of a dish-shaped member 5 which is protruded downward with a mounting bolt 4 from the lower or central part.
The lower end flange 6a of the cylindrical member 6 is fixed by fastening or other means, and the other frame 2 is attached to the lower surface of a flat plate 8 provided with a mounting bolt 7 projecting upward from the center of the upper surface. , by fixing the cup-shaped member 9.

Further, here, the elastic member 3, which can be made of rubber or a rubber-like elastic material, is formed into a hollow substantially truncated conical shape, and in the figure, the lower end surface thereof is the upper end enlarged portion 6b of the cylindrical member 6.
, and force its upper end surface.

The elastic member 3 is brought into close contact with the frame 1.degree. 2 by adhering it to the circumferential surface of the elastic member 9 by vulcanization or other means.

Here, the elastic member 3 has a peripheral portion clamped between the cylindrical member 6 of the frame l, the cup-shaped member 9 of the frame 2, and the dish-shaped member 5 and the cylindrical member 6 of the frame 1. Together with the diaphragm 10, they contribute to the formation of a sealed chamber, and in the illustrated example, water or other incompressible liquid having a required viscosity is sealed throughout the sealed chamber 11 defined by these members.

In this example, such a sealed chamber 11 containing a liquid is also separated between two liquids by a partition wall 12 whose periphery is clamped liquid-tight between the dish-like member 5 and the cylindrical member 6. Divided into chambers 13.14, both of these chambers 13.14
are made to communicate with each other by opening a throttle passage 15 provided in the partition wall 12 to each of them.゛Here, the throttle passage that opens into both liquid chambers 13 and 14 is
It can also be formed at a position inside or outside the sealed chamber 11, independent of the partition wall 12.

In addition, this partition wall 12 in the illustrated example is a deformation restraint plate 1
Metal flanges 17a and 18a are caulked by vulcanizing or otherwise bonding flexible membrane bodies, such as rubber membranes 17°I8, which are arranged at a predetermined distance in the vertical direction with respect to the metal flanges 17a and 18a, which are separated from each other by vulcanization or other means. The caulked parts of these rubber membranes 17 and 18 are vertically sandwiched between the inward flanges 19a and 20a of the outer cylindrical member 19 and the inner cylindrical member 20 located on the outer periphery of the outer cylindrical member 19 and the inner cylindrical member 20. Outward flange 19 of member 19°20
b, 20b can be constructed by sandwiching the diaphragm 10 between the dish-shaped member 5 and the cylindrical member 6.

In such a partition wall 12, each liquid chamber 13,
The rubber membranes 17 and 18 located adjacent to the rubber membranes 14 form the sub-liquid chamber 21 by sealing the required liquid into the space formed by them. The deformable restraint plate 16, which can be constructed as shown in FIG.

The partition wall 12 also defines the aforementioned throttle passage 15 between the outer cylinder member 19 and the inner cylinder member 20, and the liquid chambers 13 and 14.
allow the flow of liquid through it. In the illustrated example, this throttle passage 15 extending in the circumferential direction of the cylindrical member 6 is connected to the liquid chamber 13.1 at a position diametrically opposed to the throttle passage 15.
The positions of these openings are as follows.
Of course, it can be selected as appropriate depending on the required extension length of the throttle passage 15.

When using the vibration isolating device configured in this way as an engine mount, the frame 1 is attached to the automobile body.
The frame body 2 is also connected to the engine via respective mounting bolts 4.7.

Here, if the vibration transmitted from the engine (not shown) to the frame body 2 is a low-frequency, large-amplitude vibration, the internal friction of the elastic member 3a will dampen the vibration to some extent, and Based on the alternating increase and decrease of the internal pressure of 13.14, the liquid in those liquid chambers flows through the throttle passage I
When flowing from one liquid chamber to the other liquid chamber through step 5,
Flow resistance and liquid column resonance will provide a sufficiently effective damping of the low frequency, large amplitude vibrations.

Note that when the liquid in the liquid chamber flows in this manner, the liquid chamber 13
The liquid flowing into the liquid chamber 14 from the diaphragm 10 increases the volume of the liquid chamber 14 by an amount corresponding to the volume reduction of the liquid chamber 13 based on the elastic deformation of the diaphragm lO. If a through hole is provided to provide communication between the inside and the outside, the back pressure acting on the diagram 10 will be reduced and the fluid will flow more smoothly.

It should be noted that during such alternating flow of liquid in the liquid chambers 13.14, the rubber membranes 17.18
4 side or the opposite side is deformed to the deformation limit position, which is limited by the contact of either one of the rubber membranes with the deformation restraining plate 16.

On the other hand, when the throttle passage 15 is closed due to high frequency and small amplitude vibrations being transmitted to the frame 2, the rubber membrane 17.18 responds to internal pressure fluctuations in the liquid chamber 13.14. 2, for example, as shown in FIG. 2, the relative vibration of the frame 2 with respect to the frame 1 is sufficiently tolerated without causing an increase or decrease in the internal pressure of the liquid chamber. Therefore, sufficient insulation of high-frequency vibrations from the vehicle body is achieved here without increasing the dynamic spring constant of the vibration isolator.

Such deformation of the rubber membrane 17.18 here results in a preselected minute gap between the deformation restraining plate 16 and the rubber membrane 17.18, in other words, it is possible to sufficiently absorb high frequency and small amplitude vibrations while reducing the The deformation of both is carried out within a predetermined gap that can ensure effective damping of high-frequency, large-amplitude vibrations.
Either one of the rubber membranes is restricted by coming into contact with the deformation restraining plate 16 under a state in which the liquid in the sub-liquid chamber 21 freely flows through the through-hole 16a. Here, since the liquid volume in the sub-liquid chamber does not change at all before and after the deformation of the rubber membranes 17 and 18, the above-mentioned deformation of the rubber membranes 17 and 18
This occurs as a displacement phenomenon of the sub-liquid chamber 21 bordering on the deformation restraining plate 16.

Figures 3 and 4 are views showing other embodiments of the partition wall, in which the flexible membrane body is made of a perforated rubber membrane for the purpose of facilitating the manufacture and assembly of the partition wall I2. It is.

In the embodiment shown in FIG. 3, a perforated rubber IfPA22°23 with a metal or synthetic resin flange bonded to the circumferential surface is used as a perforated deformation restraint which can also be made of metal or synthetic resin. In this example, the partition wall 12 is constructed by arranging the plates 16 one above the other and the outer cylindrical member 19 and the inner cylindrical member 20 arranged on the outer periphery thereof in the same manner as described above. , perforated rubber membrane 22.23
The liquid chamber 21 defined by the flanges connected thereto includes through holes 22a, 2 of the rubber membrane 22.23, which have a cross-sectional area significantly smaller than the cross-sectional area of the throttle passage 15.
Although it communicates with both liquid chambers 13 and 14 via 3a, the function of this partition wall 12 is no different from that described above.

Further, the example shown in FIG. 4 is a perforated rubber membrane 2 in which reinforcing layers 22b and 23b such as cords and canvas are embedded respectively.
2.23 are integrated by caulking one flange joined to the other flange on their peripheral surfaces,
The partition wall 12 is constructed by arranging the outer cylinder member 19 and the inner cylinder member 20 with the caulked portion sandwiched therebetween.

According to this example, the perforated rubber membrane 22.23 is the reinforcing layer 22b.
.

23b, the durability of the perforated rubber membranes 22, 23 can be improved by preventing the generation of cracks from the peripheral portions of the through holes 22a, 23a.

Here, the integration of the perforated rubber membranes 22 and 23 is achieved by, for example, as shown in FIG. Also, the occurrence of cracks from the periphery of the through hole is
As also shown in FIG. 5, the respective through holes 22a,
This can also be prevented by increasing the thickness of the peripheral portion of 23a to increase the strength of that portion.

FIG. 6 is a sectional view showing another embodiment of the sub-liquid chamber;
In the example shown in Figure (al), soft plastic plates 25 and 26 are bonded to the upper and lower surfaces of the deformation restraint plate 16 by heat fusion, adhesive bonding, etc., and the sub-liquid chamber 2
According to this example, each soft plastic plate 25.26 forms a flexible membrane adjacent to the liquid chamber 13.14.

In this example, through holes 25a and 26a are formed in the soft plastic plates 25 and 26, respectively, but these may of course be omitted, and the behavior of the sub-liquid chamber 21 is determined by the through holes 25a and 26a. Regardless of the presence or absence of
The embodiment is almost the same as the embodiment shown in the figure.

Further, in the embodiment shown in FIG. 6(b), the upper and lower surfaces of the deformation restraining plate 16 made of synthetic resin are covered with woven fabric, knitted fabric, etc., for example, nylon fabric, with the mesh size appropriately selected according to the requirements. cloth 27
．． 28 respectively, and these nylon woven fabrics 27.
28 is also fixed thereto, for example, by joining the resin rings 27a, 28a to the deformation restraining plate 16, thereby defining a sub-liquid chamber 21 between both nylon fabrics, and this sub-liquid chamber 21 can also function similarly to the previous example.

(Effects of the Invention) Therefore, according to the present invention, by forming a sub-liquid chamber partitioned by a flexible membrane in the partition wall, the dynamic An increase in the spring constant can be effectively prevented.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing one embodiment of the present invention, FIG. 2 is an enlarged sectional view showing the deformed state of the rubber membrane, FIGS. 3 and 4 are views showing other embodiments of the partition wall, respectively, and FIG. The figure shows a modified example of the rubber membrane and their integration, and FIG. 6 is a sectional view showing another embodiment of the sub-liquid chamber. 1.2... Frame body 3... Elastic member 11.
... Sealed room 12 ... Partition walls 13, 14.
...Liquid chamber 15...Aperture passage 16...Deformation restraint plate 16a...Through holes 17, 18, 22.
23...Rubber membrane 19...Outer tube member 20...Inner tube member 21...Subliquid chambers 25, 26...Soft plastic plates 27, 28...Nylon woven fabric Fig. 1 □□ □□□□□□□□□□□□□□□□□□□□□□□
□□□□□□□□□□Hand view

Claims (1)

[Claims] 1. Two frames each connected to different members;
An elastic member placed between these two frames contributes to the formation of a sealed chamber, a liquid sealed in the sealed chamber, and a peripheral portion fixed to one of the frames to divide the sealed chamber into two liquid chambers. In a vibration isolating device comprising a partition wall and a passage that brings communication between the two liquid chambers, a sub-liquid chamber is formed in the partition wall, and a portion of the sub-liquid chamber adjacent to the two liquid chambers is made flexible. A vibration isolating device characterized by being divided by a flexure membrane.