JP2002310223A - Structure of elastic diaphragm for liquie sealed vibration isolator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To vary the spring elasticity of an elastic diaphragm non-linearly and by multi-steps. SOLUTION: The elastic diaphragm assembly 10 is assembled with the elastic diaphragm 40 disposed between a support part main body 20 and a lid 30. The elastic diaphragm 40 has a circular wall 43 for fixing in the outer periphery, a first support point 46 at the center, a second support point 47 in the middle part, and an inner side stopper 48 on the inner side and an outer side stopper 49 on the outer side with the second support point 47 in-between. The first support point 46 and the second support point 47 are pressure-welded to the support part main body 20 and the lid 30. The inner side stopper 48 and the outer side stopper 49 are made to project in the vibration input direction, inclined toward the center of elastic deformation, and pressed on the support part main body 20 and the lid 30 from the direction orthogonally crossing the main vibration input direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elastic film structure for a liquid-sealed vibration isolator, and more particularly to an elastic film structure in which the spring elasticity is changed in a multi-stage and non-linear manner.

[0002]

2. Description of the Related Art A liquid seal vibration isolator provided with an elastic film is known. FIG. 8 shows an outline of a liquid-sealed vibration isolator including an example of an elastic film. This liquid ring vibration isolator is a conical mount for supporting the engine, and has a first mounting portion 1 mounted on the engine side.
And a second mounting portion 2 mounted on the vehicle body side are connected by a conical rubber body 3, the internal space of the rubber body 3 is sealed by a diaphragm 4, and a partition member 5 is provided inside to form a main liquid chamber. 6 and a sub-liquid chamber 7, and the two liquid chambers are communicated with each other through an orifice passage (not shown). The partition member 5 is a rigid frame 8 fixed around an elastic film 9 made of rubber or the like. In addition, the main liquid chamber 6 absorbs the elastic deformation of the main liquid chamber 6 due to the internal pressure fluctuation.

[0003]

By the way, such a liquid-sealed vibration isolator has such a characteristic that it has a low dynamic spring for small vibrations and a high damping for large vibrations in order to improve ride comfort. Is required, and such characteristics can be realized by an elastic film. However, in the case of the above-described conventional structure, since the outer peripheral portion of the elastic film 9 is merely fixed by the frame 8 from the main vibration input direction Z, that is, the vertical direction in the figure, the spring elasticity in the elastic deformation of the elastic film 9 is not increased. It is substantially constant, and the relationship between the applied force and the amount of deformation is substantially linear. Therefore, if priority is given to riding comfort that absorbs small vibrations, high damping cannot be obtained, while
If it was set to give priority to the damping of large vibrations, a low dynamic spring would not be attained, so a compromised intermediate setting had to be made. Accordingly, an object of the present invention is to make the spring elasticity multi-stage and non-linearly changeable without such a compromise.

[0004]

According to a first aspect of the present invention, there is provided a liquid sealing and vibration isolating device which is divided into a main liquid chamber, a sub liquid chamber, and a partition member. In the liquid seal vibration isolator in which the liquid chamber communicates with the orifice passage and the partition member is provided with an elastic film for absorbing the internal pressure fluctuation of the main liquid chamber, the outer peripheral portion of the elastic film is fixed to the supporting member, and A first support point is provided on the portion, and a second support point is provided at an intermediate portion between the center portion and the outer peripheral portion, each of which is brought into contact with the support member, and is provided to the support member in a direction substantially orthogonal to the main vibration input direction. It is characterized in that a side stopper is provided to abut.

According to a second aspect, in the first aspect,
The side stopper is formed integrally with the elastic film as a protrusion protruding in a main vibration input direction, and a protruding end is inclined with respect to the main vibration input direction so as to approach a deformation center direction of the elastic film. And At this time, the side stoppers may be arranged on the outer peripheral side and the center side of the elastic film with the second support point interposed therebetween.

[0006]

According to the first aspect of the invention, the outer peripheral portion of the elastic film is fixed, the first supporting point is provided at the center, and the second supporting point is provided at the intermediate portion.
Is provided, when a small vibration is input, first, the whole is elastically deformed, the first support point is compressed, and the spring elasticity gradually increases. At this stage, a small vibration is absorbed and a low dynamic spring is formed. When the compression of the first support point reaches a limit, elastic deformation occurs between the first support point and the outer peripheral portion with the first support point as a fulcrum. Therefore, since the span of the elastic deformation is reduced by half, the spring elasticity is increased. The elastic deformation at this stage is performed while compressing the second support point, so that a relatively large vibration can be absorbed and a relatively low dynamic spring is maintained.

[0007] When the second support point eventually reaches the compression limit,
With the second support point as a fulcrum, the elastic deformation is changed between the second support point and the first support point and between the second support point and the outer peripheral portion. In this elastic deformation, since the deformation span is further reduced by half, the spring elasticity is significantly increased. Moreover, since the side stopper is strongly pressed against the support member, the spring elasticity is also increased, and as a result, high damping can be realized. Moreover, since the first support point, the second support point, and the side stopper are pressed against the support member from the beginning, no hitting sound is generated, and noise is reduced. Further, since the side stopper is pressed against the support member from a direction substantially perpendicular to the main vibration input direction, the side stopper can contribute to a non-linear change in spring elasticity and does not hinder elastic deformation of the elastic film.

According to the second aspect of the present invention, the side stopper is a projection protruding in the main vibration input direction, and the tip is inclined so as to approach the center of elastic deformation in the elastic film with respect to the main vibration input direction. Initially, the elastic member is not strongly pressed against the support member, but is gradually pressed strongly as the amount of elastic deformation of the elastic film increases, so that the spring elasticity increases progressively. Therefore, a non-linear change in spring elasticity can be remarkably exhibited.

At this time, if the side stoppers are arranged near the first support points of the outer peripheral portion and the central portion with the second support points interposed therebetween, the center stops from the stage where the first support points become the fulcrum of deformation. Since the effect of the side stopper is generated at the portion and the outer peripheral portion, the step change of the spring elasticity due to the side stopper can be further increased.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a plan view of an elastic membrane assembly in which an elastic membrane and a support are integrated, FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1, and FIG.
FIG. 4 is a plan view of the elastic film, FIG. 5 is a cross-sectional view taken along the line 5-5 in FIG. 4, and FIG. 6 is a diagram illustrating fastening of the elastic film. FIG. 7 is a diagram showing the operation in principle.

First, in FIGS. 1 and 2, the elastic membrane assembly 10 is provided between the support body 20 and the lid 30.
0 is sandwiched and integrated, and has a circular shape in plan view as a whole. A groove 21 that opens upward in FIG. 2 is provided on the outer periphery of the support portion main body 20, and the damping orifice passage 11 is formed using the groove 21. An annular groove 23 having a substantially U-shaped cross section is provided on the inner peripheral side of an annular partition wall 22 which forms the inner wall surface of the groove 21, and the inner peripheral wall 24 of the annular groove 23 serves as a vertically long pressing surface in FIG. 2. Has become.

The inner portion surrounded by the annular partition wall 22 is an elastic film 40 accommodating portion. Eggplant An intermediate portion between the central portion 26 and the inner peripheral wall 24 forms an intermediate fixing portion 27. The intermediate fixing portion 27 is a part of the bottom portion 25, and has openings 28,
29 are formed. A plurality of openings 28 and 29 are formed at equal intervals on a concentric circle. In particular, the opening 29 is formed in a long arc shape, and these correspond to the opening formed on the lid 30 side (see FIG. 1).

The lid 30 is a substantially disk-shaped member made of metal.
The outer peripheral portion 31 covers the opening of the groove 21 and forms the damping orifice passage 11 together with the groove 21. Although not shown, an inlet of a damping orifice passage which opens to the main liquid chamber is formed in the outer peripheral portion 31 so that the support body 2
An outlet opening to the sub liquid chamber is provided on the bottom side of the outer peripheral portion of O. A portion which moves from the outer peripheral portion 31 to the inner peripheral side of the lid 30 and which is on the inner peripheral side and above the annular groove 23 from the contact portion with the annular partition wall 22 is a stepped portion 33 which falls to the lower side in FIG. Make

The inner peripheral part of the lid 30 from the outer peripheral part 31 is the bottom part 2.
5 is a circular ceiling portion 35, and the center 36 of the circular ceiling portion 35 is curved so as to protrude upward in FIG. An intermediate fixing portion 37 and openings 38 and 39 are formed at positions corresponding to the intermediate fixing portion 27 and the openings 28 and 29, respectively. The intermediate fixing part 37 is a part of the ceiling part 35. An appropriate space is provided between the bottom part 25 and the ceiling part 35 to accommodate the elastic film 40.

As shown in FIGS. 4 and 5, the elastic film 40 is a member made of an appropriate elastic material such as rubber or elastomer.
A plurality of protrusions are integrally formed in the vertical direction in FIG. First, an annular wall 43 that fits into the annular groove 23 is formed on the outer peripheral portion so as to protrude in the vertical direction in FIG. 5, and is formed at a position corresponding to the first support point 46 and the intermediate fixing portions 27 and 37 at the center. Are located at positions corresponding to the second support points 47 and the openings 28 and 38, and the inner side stoppers 48 and the openings 29 and
An outer side stopper 49 is provided at a position corresponding to 39.

The first support point 46 is fitted at its tip into the central portions 26 and 36, and the second support point 47 abuts on the intermediate fixing portions 27 and 37. In addition, as shown in FIG. 6, the tips of the first support point 46 and the second support point 47 are
A longer protruding interference is provided so as to be compressed at the time of assembly by the 6 and the intermediate fixing portions 27 and 37.

The inner side stopper 48 and the outer side stopper 49 are formed to be long so as to protrude from the openings 28, 38 and 29, 39 to the outside. In addition, each opening 2
The size of 8, 29, 38, and 39 is such that the length in the circumferential direction is substantially the same as the length of the inner side stopper 48 and the outer side stopper 49, and the length of the inner side stopper 48 and the outer side stopper 49 in the radial direction. The frontage is wide open to allow elastic deformation.

FIG. 3 is an enlarged view showing the interference with respect to the central portion 26 at the first support point 46. In addition. The same applies to the center portion 36 side. A in the upper part indicates a state at the time of assembling, and the interference 50 indicated by an imaginary line formed at the tip of the first support point 46 is compressed and disappears.
There is still a gap 51 around the periphery pressed against the central portion 26 of FIG.
Are formed.

FIG. 3B shows the state of the first support point 46 when the elastic film 40 is elastically deformed.
When the support point 46 is strongly pressed against the center portion 26 and compressed, the elastic portion is elastically deformed so as to fill the gap 51, and the filling portion 52 filling the gap 51 indicated by oblique lines is formed. In this state, the spring elasticity of the first support point 46 becomes extremely large and changes non-linearly.

As shown in FIG. 5, the inner side stopper 4
Numeral 8 is inclined so that the tip is directed outward in the radial direction with respect to the main vibration input direction Z. This inclination direction is elastic deformation between the first support point 46 and the annular wall 43 around the second support point 47 at the stage when the inner side stopper 48 functions, so that the center of elastic deformation, that is, the second It will be inclined to the support point 47 side. Note that the inclination angles a and b are appropriately determined, and adjustment such as matching or making either side larger is possible. Alternatively, only the surface pressed against the support body 20 and the lid 30 without tilting the whole may be formed in a tapered shape.

On the other hand, the outer side stopper 49 is inclined toward the center. In this case, both the initial stage where the first support point 46 is the center of the elastic deformation and the subsequent stage where the second support point 47 is the center are inclined toward the center of the elastic deformation. Further, the inclination angles c and d can be set arbitrarily as in the case of the inner side stopper 48.

Next, the operation of this embodiment will be described. FIG. 7 schematically shows the deformation of the elastic film 40.
Is a basic state before elastic deformation. B is an initial stage of elastic deformation, and corresponds to small vibration having a relatively small amplitude. At this stage, since the annular wall 43 of the outer peripheral portion is fixed, the first
While compressing the supporting point 46, the entire elastic film 40 is curved downward in one arc shape, and absorbs vibration in a state where the spring elasticity is relatively small, so that a low dynamic spring is obtained.

In the case of C, when the larger vibration is applied and the compression limit of the first support point 46 is reached, the first support point 46 becomes a fixed point, so that the annular wall 43 and the first support point 46 are fixed to each other. Then, elastic deformation occurs around the second support point 47, and the elastic film 40 has a substantially W-shaped cross section as a whole. At this stage, since the span of the elastic deformation is reduced by half, the spring elasticity is increased stepwise, and a larger vibration can be absorbed.

D indicates a state in which a further large vibration has been input. In this case, the second support point 47 is also at the compression limit, so that the second support point 47 is used as a fulcrum and the second support point 47 is used as a fulcrum. Between the annular walls 43 and between the second support point 47 and the first support point 4
Elastic deformation occurs between 6. That is, the elastic deformation is further performed between the annular wall 43 and the first support point 46 to have a substantially W-shaped cross section, and the span of the elastic deformation is further reduced by half. As a result, the vibration is attenuated by the vibration of the liquid column in the damping orifice passage, and the vibration is attenuated.

Further, in this state, the inner side stopper 48 and the outer side stopper 49 are inclined such that their respective ends on the elastic deformation side, that is, the respective lower ends in the figure, are away from the second support point 47, and each is intermediate. It is strongly pressed against the fixing portion 27 and the inner peripheral wall 24. Opening 2
8 and the outer side stopper 49 are initially inclined in a direction to reduce the contact with the intermediate fixing portion 27 and the inner peripheral wall 24, so that the change in the spring elasticity due to this pressing increases non-linearly. Therefore, the inner side stopper 48,
The outer side stopper 49 can also amplify a non-linear change in spring elasticity in the elastic film 40.

Further, since the inner side stopper 48 and the outer side stopper 49 are pressed against the support portion main body 20 or the lid 30 from a direction substantially perpendicular to the main vibration input direction Z, the inner side stopper 48 and the outer side stopper 49 are protected against small vibrations. This does not contribute much to the change in spring elasticity and contributes to lower dynamic spring. Further, the elastic deformation of the elastic film 40 is not hindered because it does not directly resist elastic deformation above and below the elastic film 40.

In addition, since the first support point 46, the second support point 47, the inner side stopper 48, and the outer side stopper 49 are initially brought into contact with the support body 20 or the lid 30, the elastic film 40 is provided. Even if elastically deformed, the generation of a tapping sound is reduced, which helps to reduce noise.

The present invention is not limited to the above embodiments, and various modifications and applications are possible within the principle of the present invention. For example, if the number of support points is two or more, it is arbitrarily possible to increase the number. Further, the present invention can be applied to automobiles and other various vibration dampers other than engine mounts.

[Brief description of the drawings]

FIG. 1 is a plan view of an elastic membrane assembly according to an embodiment.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is an enlarged view showing a structure for pressing a first support point.

FIG. 4 is a plan view of an elastic membrane.

FIG. 5 is a sectional view taken along line 5-5 of FIG. 4;

FIG. 6 is a diagram illustrating tightening of an elastic film.

FIG. 7 shows the principle of operation.

FIG. 8 is a schematic diagram of a conventional example.

[Explanation of symbols]

10: elastic membrane assembly, 20: support body, 30: lid
40: elastic membrane, 43: annular wall, 46: first support point, 4
7: second support point, 48: inner side stopper, 49:
Outer side stopper

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3J047 AA03 DA02 FA02

Claims (3)

[Claims] A main liquid chamber, a sub liquid chamber, and a partition member;
In the liquid ring vibration isolator in which the main liquid chamber and the sub liquid chamber communicate with each other through the orifice passage, and the partition member is provided with an elastic film for absorbing the internal pressure fluctuation of the main liquid chamber, the outer peripheral portion of the elastic film is supported by a supporting member. And a first support point in the center and a second support point in the middle between the center and the outer periphery,
An elastic film structure for a liquid ring vibration isolator, wherein each of the elastic film structures is provided with a side stopper which comes into contact with the support member and abuts on the support member in a direction substantially orthogonal to a main vibration input direction. 2. The side stopper is formed integrally with the elastic film as a protrusion protruding in a main vibration input direction, and is inclined so that a protruding end approaches a deformation center direction of the elastic film with respect to the main vibration input direction. The elastic film structure for a liquid-sealed vibration isolator according to claim 1, wherein: 3. The liquid ring vibration isolator according to claim 1, wherein the side stoppers are arranged on the outer peripheral side and the center side of the elastic film with the second support point interposed therebetween. Elastic membrane structure for equipment.