JPH04341629A - Cylindrical vibro-isolator - Google Patents

Abstract

PURPOSE:To prevent both low and high frequencies from occurring by installing an acutator in space between an outer cylinder that is bridged to an inner cylinder through support rubber and an interval between both liquid chambers inside is interconnected by an rounding orifice, and a holding outer cylinder concentrically installed at the outside of the former. CONSTITUTION:In a cylindrical vibro-isolator 10, an interval between the outer cylinder 12 and the inner cylinder 14 is bridged to each other through support rubber 16. In addition, In an inner part of this outer cylinder 12, there are provided two liquid chambers 18, 24 as partitioned off at both sides of this support rubber 16. Moreover, the interval between both these liquid chambers 18 and 24 is interconnected by a rounding orifice 31. In the above constitution, an actuator unit holding outer cylinder 34 is concentrically installed at the outside of the outer cylinder 12. In this case, an actuator unit 36 is installed in space between the actuator unit holding outer cylinder 34 and the outer cylinder 12. With this constitution, a vibration in the actuator unit 36 is superposed on that of an unillustrated engine being connected to the inner cylinder 14, thereby preventing any vibration, especially both medium and high frequencies.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylindrical vibration isolator for preventing the propagation of mechanical vibrations.

0002

2. Description of the Related Art An example of a cylindrical vibration isolator is a cylindrical liquid-sealed engine mount for front-wheel drive automobiles. An example is shown in FIG. This engine mount 10 has an inner cylinder 14 arranged eccentrically within an outer cylinder 12, and these inner and outer cylinders 1.
2 and 14 are bridged by a support rubber 16 via a partition wall 26. A first liquid chamber 18 is configured by the partition wall 26 and the support rubber 16. Further, the diaphragm 22 and the partition wall 26, which are supported via the stopper 20 attached to the edge of the supporting rubber 16 opposite to the first liquid chamber 18,
A liquid chamber 24 is configured. This partition wall 26 has both liquid chambers 18
, 24 have ports 28 and 30, respectively, thereby forming a circular orifice 30 that communicates the first liquid chamber with the second liquid chamber. The outer cylinder 12 is connected to the vehicle body side of the automobile, and the inner cylinder 14 is connected to the engine side.

0003

[Problem to be solved by the invention] Engine vibrations include
Low to medium frequency vibrations such as shake vibrations of around 10Hz while driving (free vibrations due to resonance between the engine mass and engine mount) and vibrations of around 30Hz during idling, and high frequency and small amplitude vibrations of several 100Hz. be. In the cylindrical engine mount shown in FIG. 11, it is possible to attenuate low- and medium-frequency vibrations to some extent due to the resonance phenomenon of the liquid column in the orbiting orifice 30, but it is not sufficient to attenuate high-frequency vibrations. There are problems that cannot be addressed.

[0004] An object of the present invention is to provide a cylindrical vibration isolator that can simultaneously damp low frequency free vibrations and medium and high frequency vibrations.

[0005]

[Means and operations for solving the problem] In order to solve the above problem, the invention of this application has an actuator unit built into a conventional cylindrical vibration isolator, and the active In addition to proactively damping medium- and high-frequency vibrations through mechanical vibrations, it is also possible to simultaneously dampen low-frequency free vibrations by using the resonance phenomenon of the liquid column, the viscous resistance of the liquid, or the loss characteristics of high-damping materials. .

Specifically, the vibration isolating device of the invention according to claim 1 includes:
It has a dual inner and outer cylinder, the two cylinders are bridged by a support rubber, and there are two liquid chambers on both sides of the support rubber inside the outer cylinder.
In a cylindrical vibration isolator in which both liquid chambers are communicated with each other by a circulating orifice, an actuator unit holding outer cylinder is disposed concentrically on the outside of the outer cylinder, and the actuator unit holding outer cylinder and the outer cylinder are arranged between the outer cylinder and the outer cylinder. (Figure 1).

[0007] The vibration isolator according to the second aspect of the present invention has a dual inner and outer cylinder, the two cylinders are bridged by a support rubber, and a dashpot that is linked to the relative displacement of the two cylinders is disposed in the space between the two cylinders. An actuator unit holding outer cylinder is arranged concentrically on the outside of the outer cylinder, and an actuator unit is arranged between this actuator unit holding outer cylinder and the outer cylinder (FIGS. 4 and 5).

[0008] The vibration isolator according to claim 3 has dual cylinders, an inner and outer cylinder, and an actuator unit is loaded between the cylinders via a rubber elastic body, and the output end of the actuator unit is connected to one of the cylinders. A dashpot is placed between the two cylinders, which is brought into contact with the cylinder and linked to the relative displacement of the two cylinders (Figures 6-1).
0).

[0009] According to a fourth aspect of the invention, instead of the dashpot of claims 2 and 3, the dashpot is supported by a high damping rubber or filled with a high damping material mechanically parallel to the support rubber.

[0010] The vibration isolating device according to claim 5 is provided with a bellows type dashpot instead of the piston cylinder type dashpot according to claims 2 and 3 (Figs. 17 and 1).
8).

[0011] The vibration isolator according to a sixth aspect of the present invention has a double inner and outer cylinder, the two cylinders are bridged by a supporting rubber, and the space between the two cylinders is divided into two liquid chambers by the supporting rubber. With,
These two chambers communicate through an orifice, an actuator unit holding outer cylinder is arranged concentrically on the outside of the outer cylinder, and an actuator unit is arranged between the actuator unit holding outer cylinder and the outer cylinder. (Figure 19).

[0012] The vibration isolator according to a seventh aspect of the present invention has dual cylinders, an inner and outer cylinder, and an actuator unit is loaded between the cylinders via a support rubber and a rubber elastic body, and the output end of the actuator unit is connected to either of the cylinders. The space between the two cylinders is divided into two liquid chambers by the supporting rubber, and
These two chambers are communicated by an orifice (
Figure 20).

[0013] In the above invention, the actuator unit includes anything that actively generates mechanical vibration, and in particular, electrostriction, magnetostriction, hydraulic pressure, pneumatic pressure, electromagnetic force,
It uses a motor, electric fluid, magnetic fluid, etc.

[0014] If a sufficiently large vibration amplitude cannot be obtained with the actuator unit alone, an amplitude enlarging mechanism may be attached to the actuator unit.

[0015]

[Operation] When the vibration isolating device of the present invention is installed in an automobile, one of the inner and outer cylinders is connected to the engine that is a source of vibration, and the other is connected to the vehicle body.

In the vibration isolator of the first aspect, low frequency vibrations are attenuated by the orifice, and high frequency vibrations are superimposed with active vibrations of the actuator unit, thereby providing effective vibration prevention for both low and high frequencies. A vibration effect is obtained.

[0017] In the vibration isolating device according to claim 2, claim 1
In place of the orifice, a dashpot is provided that is linked to the relative displacement between the inner and outer cylinders, and low-frequency vibrations are damped by the viscous resistance of this dashpot.

In the vibration isolating device according to claim 3, the actuator unit is supported between the inner and outer cylinders via the supporting rubber and the rubber elastic body, and the actuator unit cancels out high frequency vibrations and the dashpot reduces vibrations. Frequency oscillations are damped.

When an actuator unit element made of laminated piezoelectric ceramics is used, only minute dimensional changes can be achieved, so the actuator unit is provided with a width widening mechanism. Widening mechanisms include mechanical ones such as links, levers, and wedges, hydraulic ones that seal liquid,
Alternatively, a combination of these can be used. In this way, the vibration of the actuator unit is magnified by the width expanding mechanism, so that even large vibrations of the vibration source can be effectively damped.

[0020] In order to protect the function of the actuator unit, an elastic body such as rubber may be disposed between the outer cylinder and the outer cylinder for holding the actuator unit. In this case,
The actuator unit and the rubber elastic body may be disposed alternately in the circumferential direction, or the actuator unit may be disposed embedded in the rubber elastic body. In this way, even if the actuator unit is damaged, the outer cylinder and the actuator holding outer cylinder can be prevented from separating from each other. Further, it is not necessary to burden the actuator unit with unnecessary weight.

[0021]

Embodiment FIG. 1 shows an embodiment of the invention according to claim 1.

In this embodiment, the outer cylinder 12 and the inner cylinder 1
4. The arrangement relationship of the support rubber 16, both liquid chambers 18 and 24, the circulating orifice 26, etc. is the same as in the case of FIG.

In this embodiment, an outer cylinder 3 for holding the actuator unit is provided concentrically outside the outer cylinder 12.
4 is provided between the actuator unit holding outer cylinder 34 and the outer cylinder 12, an actuator unit 36 and an actuator unit holding outer cylinder 3 are provided.
4 and rubber elastic bodies 38 are arranged alternately in the circumferential direction. The actuator unit 36 is the outer cylinder 1
2 and the outer cylinder 34 for holding the actuator unit, and the actuator unit 36 uses electrostriction, magnetostriction, hydraulic pressure, pneumatic pressure, electromagnetic force, motor and cam. It is possible to use a combination of the above, an electric fluid, a magnetic fluid, etc.

Similar to the case shown in FIG. 21, this engine mount 10 has an inner cylinder 14 connected to the engine side, and an outer cylinder 12 connected to the engine side.
is connected to the vehicle body. When the actuator unit 36 is driven in response to engine vibrations, the vibrations of the actuator unit 36 are superimposed on the engine vibrations, thereby preventing transmission of engine vibrations. This actuator unit is particularly useful for isolating medium to high frequency and small amplitude vibrations. Furthermore, relatively low frequency vibrations are damped by the liquid column resonance caused by the circulating orifice 30, as in the case of FIG.

In the embodiment described above, the actuator units 36 and the rubber elastic bodies 38 are arranged alternately in the circumferential direction, but instead of this, as shown in FIG. The actuator unit 36 may be held between the elastic bodies 38, or the actuator unit 36 may be embedded within the rubber elastic body 38, as shown in FIG.

FIG. 4 shows an embodiment of the invention according to claim 2.

In this embodiment, the structure between the outer cylinder 12 and the actuator unit holding outer cylinder 34 is the same as that shown in FIG. Inside the outer cylinder 12, as shown in FIG.
Unlike the case of , it does not have a circulating orifice 30, but instead has a dashpot 40. In detail, the supporting rubber 16 bridging the inner and outer cylinders 12 and 14
extends downward in the figure to form a cylinder 42 for the dashpot. Inside the cylinder 42 is a liquid chamber 4
3, and a dashpot piston 4 is installed in the liquid chamber 43.
4, and this piston 44 is attached to the inner cylinder 14 via a support shaft 46.

In this embodiment, low frequency, large amplitude free vibrations are damped by the viscous resistance of the dashpot 40.

FIG. 5 is a modification of FIG. 4.

In this case, a cylinder 48 for a dashpot, which is constructed separately from the support rubber 16, is attached so as to come into contact with the lower end of the inner cylinder 14 in the figure. Outer cylinder 12
A dashpot piston 50 is fixed via a support shaft 52 at a position facing the cylinder 48 .

FIG. 6 shows an embodiment of the invention according to claim 3.

In this embodiment, both the inner and outer cylinders 12,1
An actuator unit 54 is arranged between the two. In detail, this actuator unit 54 is
6, and this case 56 has a support part 58 at the upper part in the figure, and this support part 58 has a support rubber 16.
It is attached to the outer cylinder 12 via the holding rubber 60, and to the inner cylinder 14 via the holding rubber 60. A flange portion 61 is provided below the support portion 58, and a cylindrical housing 62 is formed below the flange portion 61. The flange portion 60 is open on both the upper and lower sides, and a small diameter piston 64 is disposed in the upper opening, and a large diameter piston 66 is disposed in the lower opening so as to be vertically slidable. A bottom cap 68 is threaded onto the lower portion of the housing 62 . A piezo actuator 70 is disposed inside the housing 62 , the lower end of which is supported by a bottom cap 68 , and the upper end of which abuts against the lower surface of the large diameter piston 66 .

In this embodiment, the output of a displacement sensor and/or acceleration sensor (not shown) is input to an actuator unit control device (also not shown), and this control device generates an electric vibration signal according to the magnitude of the output of the sensor. is applied to the piezo actuator 70. As a result, the piezo actuator 70 expands and contracts by a very small amount in the vertical direction. At that time, the liquid chamber 72 configured between the large and small pistons 64 and 66
The cross-sectional area of the piezo actuator 70 is large at the bottom and small at the top, so according to Pascal's principle, the minute mechanical vibrations of the piezo actuator 70 are converted into large-amplitude vibrations according to the area ratio of the two. The information is transmitted to the piston 64. In this way, when the engine is lowered, the smaller diameter piston 56 is lowered by the same amount as the engine is lowered in response to the output of the displacement sensor and/or acceleration sensor, and conversely, when the engine is lowered, the smaller diameter piston 56 is lowered by the same amount as the engine is lowered. Piston 64 rises.

The liquid chamber 72 is described in Japanese Patent Application No. 2-31498.
According to the teachings of 4, a velofram can be placed in the upper part and a diaphragm in the lower part. In this way, leakage of the liquid in the liquid chamber 72 can be prevented. Alternatively, the liquid chamber 72 may be filled with a liquid covered with a rubber-like elastic film. Furthermore, the liquid chamber 72 may be filled with an incompressible rubber-like elastic body or a gel-like substance as a vibration transmission medium instead of a liquid. In this case, since there is no risk of leakage of these transmission media, the rubber-like elastic coating can be omitted. moreover,
Instead of liquid, the liquid chamber 72 may be filled with minute powder particles whose surfaces are preferably coated with lubricating oil. 6
If the fitting gap is made larger than the fitting gap 6, there is no risk of these powder particles leaking outside.

As described above, in this embodiment, the piezo actuator unit 70 can dampen medium-high frequency and small amplitude vibrations. Further, a piston 76 for a dashpot is disposed outside the housing 62 that forms a part of the case 56, and low frequency free vibrations can be attenuated by the viscous resistance of the dashpot.

FIG. 7 is a modification of FIG. 6, in which a dashpot mechanism 78 similar to that in FIG. 5 is provided in place of the dashpot mechanism 75 in FIG.

FIG. 8 shows another modification of FIG. 6, in which the dashpot mechanism 79 has a U-shaped cup 80 fitted around the outer periphery of the piezo actuator housing 62, and the cup 80 has an orifice 81. have. The viscous resistance of the liquid passing through the orifice 81 acts as a dashpot.

FIG. 9 shows yet another modification of FIG. 6,
In this case, the piezo actuator 70 does not have a width expanding mechanism, and the piezo actuator 70 is provided with cover plates 82 and 84 having a protrusion in the center at both upper and lower ends, respectively.
Touch plates 86 and 88 are provided on the inner surfaces of the inner cylinder 14 and the bottom cap 68, respectively.
, 84 are in contact with the touch plates 86, 88.

In FIGS. 6 to 9, the output end of the actuator unit 54 is brought into contact with the inner cylinder 14, but the output end may be brought into contact with the outer cylinder 12 instead. That is, as shown in FIG. 10, inside the outer cylinder 12, an arcuate support member 58 is attached to the outer cylinder 12 via the rubber elastic body 38 and to the inner cylinder 14 via the support rubber 16. The actuator unit 54 is arranged between the support member 58 and the outer cylinder 12 so that its output end is in contact with the outer cylinder 12. Support member 58 and support rubber 16
A dashpot mechanism 91 is arranged between.

In all the embodiments described above, the inner cylinder 14
, the outer cylinder 12, and the actuator holding outer cylinder 34 are not limited to true cylinders, and even if they are elliptical cylinders, rectangular cylinders, or segments (parts, sections) thereof, the effects will not change. In the case of FIG. 10, the support member 58 is formed in segments.

The liquid in the dashpot shown in FIGS. 4-10 may be water, oil, antifreeze, or the like, and may also be grease, gel, sol, liquid rubber, or the like.

Further, in FIG. 4, the dashpot 40 is arranged in the space between the support rubber 16 and the outer cylinder 12, but instead of this, as shown in FIG. A high damping rubber 100 may be disposed between the outer cylinder 12 and the cylinders 12 and 14 to support displacement between the cylinders 12 and 14. As the high damping rubber, one having elasticity and shape retention properties such as polynorbornene rubber is preferable. The same modification may be made to the embodiment of FIG. 6 (FIG. 12),
Similar changes can also be made to FIG. 10 (FIG. 13). Furthermore, instead of supporting with such high damping rubber 100, a high damping material 102 may be filled in the space between the supporting rubber 16 and the outer cylinder 12. Preferable examples of the high damping material include gel, sol, liquid rubber, and polynorbornene rubber. FIG. 14 shows a case where such changes are made to FIG. 4, FIG. 15 shows a case where such changes are made to FIG. 6, and
FIG. 16 shows the case in which the method shown in FIG. 10 is applied.

Furthermore, a bellows-type dashpot 110 may be provided in place of the piston-cylinder type dashpot shown in FIG. That is, as shown in FIG. 17, a bellows 112 is disposed within the liquid chamber 43, and its upper plate is fixed to a support shaft 46 attached to the inner cylinder 14. An orifice 114 is provided in the upper plate of the bellows. 116 is a ring that prevents the bellows 112 from expanding. The inside and outside of the bellows 112 are filled with liquid, and the viscous resistance of the liquid passing through the orifice 114 absorbs low frequency vibrations. 6, a similar bellows-type dashpot 110 may be provided, and is shown in FIG. 18.

Furthermore, instead of the dashpot shown in FIG. 4, two chambers divided into two by the support rubber 16 are used as liquid chambers 120 and 122, as shown in FIG.
is provided with an orifice 124 that allows these liquid chambers 120, 122 to communicate with each other. The diameter of the orifice 124 is 1 to 4 mm.
is preferred. Passage losses when the liquid passes through the orifice 124 dampen low frequency vibrations. Similar changes are shown in Figure 6.
It can also be applied in the case of This is shown in FIG.

[0045]

[Effect of the invention] In the cylindrical vibration isolator of this invention,
Both low frequency and high frequency vibrations can be effectively prevented.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the invention according to claim 1.

FIG. 2 is a sectional view of a main part showing a modification of FIG. 1;

FIG. 3 is a sectional view of a main part showing another modification of FIG. 1;

FIG. 4 is a sectional view showing an embodiment of claim 2.

FIG. 5 is a sectional view showing a modification of FIG. 4;

FIG. 6 is a sectional view showing an embodiment of claim 3.

FIG. 7 is a sectional view showing a modification of FIG. 6;

FIG. 8 is a sectional view showing another modification of FIG. 6;

9 is a sectional view showing still another modification of FIG. 6. FIG.

FIG. 10 is a sectional view showing another embodiment of claim 3.

11 is a cross-sectional view of a case where the dashpot of FIG. 4 is replaced with high damping rubber; FIG.

12 is a sectional view of the case where the dashpot of FIG. 6 is replaced with high damping rubber as in FIG. 11; FIG.

13 is a sectional view of the case where the dashpot of FIG. 10 is replaced with high damping rubber as in FIG. 11; FIG.

FIG. 14 is a cross-sectional view of a case where the dashpot of FIG. 4 is filled with a high-damping material.

15 is a cross-sectional view of a case where the dashpot of FIG. 6 is filled with a high damping material similar to that of FIG. 14; FIG.

16 is a cross-sectional view of a case where the dashpot of FIG. 10 is filled with a high-damping material similar to that of FIG. 14; FIG.

17 is a sectional view of a case where a bellows-type dashpot is used instead of the piston-cylinder type dashpot of FIG. 4. FIG.

18 is a cross-sectional view of a case where a bellows-type dashpot is used in place of the piston-cylinder-type dashpot of FIG. 6, similar to FIG. 17; FIG.

FIG. 19 is a sectional view showing a modification example replacing the dashpot shown in FIG. 4 and the like.

20 is a cross-sectional view of FIG. 6 with the same changes as FIG. 19;

FIG. 21 is a sectional view showing an example of a conventional cylindrical liquid-sealed engine mount for an FF.

[Explanation of symbols]

10...Cylindrical vibration isolator 12...Outer tube 14...Inner tube 16...Support rubber 18...First liquid chamber 24...Second liquid chamber 31...Orifice 34...Outer tube for holding actuator unit 36... Actuator unit 40... Dashpot 78... Dashpot 54... Actuator unit 60... Holding rubber

Claims (7)

[Claims] [Claim 1] Having a double inner and outer cylinder (12, 14),
The support rubber (16) bridges the two cylinders, and the outer cylinder (12
), two liquid chambers (1
8, 24), and a circulating orifice (31) between both liquid chambers.
In the cylindrical vibration isolator (10), which is connected to the outer cylinder (12), an actuator unit holding outer cylinder (34) is disposed concentrically on the outside of the outer cylinder (12), and the actuator unit holding outer cylinder (34) and the A vibration isolator characterized in that an actuator unit (36) is disposed between the outer cylinder (12) and the outer cylinder (12). [Claim 2] It has double inner and outer cylinders (12, 14),
The two cylinders are bridged by a support rubber (16), and a piston-cylinder type dashpot (40, 78) that is linked to the relative displacement of the two cylinders is arranged in the space between the two cylinders. The outer cylinder for holding the actuator unit (3
4), and this actuator unit holding outer cylinder (
34) and the outer cylinder (12), an actuator unit (36) is provided. [Claim 3] Having double inner and outer cylinders (12, 14),
The actuator unit (54) is loaded between the two cylinders via the support rubber (16) and the rubber elastic body (60), and the output end of the actuator unit (54) is connected to the cylinders (12, 14).
), and a piston-cylinder type dashpot (75, 78, 79, 90, 91) that is brought into contact with one of the cylinders (12, 14) and linked to the relative displacement of the cylinders (12, 14) is arranged between the cylinders. Features a vibration isolator. Claim 4: The dashpot (40, 78;
75, 78, 79, 90, 91), both cylinders (12
, 14), a high damping rubber (100) is arranged in the space between
The high damping rubber (100) supports the relative displacement between the cylinders (12, 14), or the space between the cylinders (12, 14) is filled with a high damping material (102). The vibration isolator according to claim 2 or 3. 5. The piston-cylinder type dashpot (40, 78; 75, 78, 79, 90, 91
4. The vibration isolator according to claim 2, further comprising a bellows-type dashpot (110) in place of the dashpot (110). [Claim 6] Having double inner and outer cylinders (12, 14),
The two cylinders are bridged by a supporting rubber (16), and the space between the two cylinders is formed by the supporting rubber (16) into two liquid chambers (120,
122), and these two rooms (120,
122) communicate with each other through an orifice (124),
An actuator unit holding outer cylinder (34) is arranged concentrically outside the outer cylinder (12), and an actuator unit (36) is arranged between the actuator unit holding outer cylinder (34) and the outer cylinder (12). A vibration isolating device characterized by having. [Claim 7] It has double inner and outer cylinders (12, 14),
The actuator unit (54) is loaded between the two cylinders via the support rubber (16) and the rubber elastic body (60), and the output end of the actuator unit (54) is connected to the cylinders (12, 14).
), the space between the two cylinders is divided into two liquid chambers (120, 122) by the support rubber (16), and these two chambers (120, 122) are connected to the orifice (124). ).