JP5969249B2 - Liquid seal vibration isolator - Google Patents

Description

The present invention relates to a liquid seal vibration isolator used for automobile engine mounts and the like, and in particular, a resonance frequency region is broadened in a low frequency region, and an internal pressure is absorbed by an elastic movable film in a frequency region higher than the resonance frequency region. This is related to a low dynamic spring and a compact device as a whole.

A liquid seal vibration isolator that encloses hydraulic fluid and utilizes liquid column resonance by an orifice is known.
FIG. 8 is a schematic diagram of an engine mount in Patent Document 1 as an example. The engine mount includes a first mounting member 101 coupled to the engine and a cylindrical first mounted on the vehicle body side. 2 An elastic insulator 103 is interposed in one opening of the mounting member 102, the other opening of the second mounting member 102 is covered with a diaphragm 104, and is surrounded by the second mounting member 102, the insulator 103, and the diaphragm 104. The space is defined as a liquid chamber, and the partition member 105 divides the space into a main liquid chamber 106 and a sub liquid chamber 107, and an attenuation orifice 108 that communicates the main liquid chamber 106 and the sub liquid chamber 107 is provided as a first orifice. An elastic film 110 is provided on the partition member 105 to absorb internal pressure fluctuations in the main liquid chamber 106.

Further, an intermediate chamber 113 is provided between the elastic membrane 110 and the sub liquid chamber 107, and this intermediate chamber 113 communicates with the sub liquid chamber 107 through an idle orifice 114, which is a second orifice. And a movable plate 190 is provided. The movable plate 190 moves up and down in the communication path between the intermediate chamber 113 and the secondary liquid chamber 107 and closes the opening of the communication path when it moves greatly to the movement limit. When the movement of the hydraulic fluid is stopped and the movement does not reach the movement limit, the movement of the hydraulic fluid is permitted by moving up and down in small increments in the communication path between the two openings.

When shake vibration, which is low frequency large amplitude vibration, is input to the engine mount, the damping orifice 108 resonates with a liquid column to realize high damping and absorb this. In addition, when idle vibration that is medium frequency medium amplitude vibration is input, the idle orifice 114 resonates with the liquid column and absorbs the idle vibration. At this time, the damping orifice 108 is clogged, there is no flow of hydraulic fluid, and the movable plate 190 moves to either the upper or lower movement limit to block the communication path between the intermediate chamber 113 and the sub liquid chamber 107. .

Further, when high-frequency and small-amplitude boom noise is input, the damping orifice 108 and the idle orifice 114 are clogged, there is no flow of hydraulic fluid, and the movable plate 190 moves up and down in small increments within the upper and lower movement limits. By allowing the hydraulic fluid to move between the intermediate chamber 113 and the sub liquid chamber 107, the elastic membrane 110 is elastically deformed to absorb the fluctuation in the internal pressure of the main liquid chamber 106, and a low dynamic spring is used to generate a booming sound. Absorb.

At this time, the elastic film 110 has both a function as an elastic member for resonance causing the liquid column resonance of the idle orifice 114 to decrease, and a function as an internal pressure fluctuation absorbing film of the main liquid chamber 106 at the time of high frequency small amplitude vibration input. To do. However, when functioning as an elastic member for resonance, the internal pressure absorbing function must be suppressed because a large amount of hydraulic fluid needs to be sent to the idle orifice 114, so that the function must be switched. The movable plate 190 works as this function switching means.

In the present invention, the low-frequency large-amplitude vibration is a vibration having a vibration frequency of 5 to 20 Hz and an amplitude of ± 1.0 mm or more, a vibration frequency of more than 20 Hz to less than 50 Hz, and an amplitude of ± 0.1 mm to 1 A vibration of less than 0.0 mm is referred to as a medium frequency medium amplitude vibration, a vibration frequency of 50 Hz or more, and a vibration of less than ± 0.1 mm is referred to as a high frequency small amplitude vibration.

JP 2011-7222 A

By the way, when both the function as the elastic member for resonance and the function as the internal pressure fluctuation absorbing film are provided in one elastic film 110 as in the above-described known example, function switching means such as the movable plate 190 is required. . However, providing such function switching means complicates the structure. Moreover, since the movable plate 190 generates abnormal noise (sounding sound) during operation due to its characteristics, special countermeasures against this abnormal noise are required.
On the other hand, in order not to provide such a function switching means, two elastic membranes separated for each function may be used. In this case, if two elastic membranes are arranged side by side, the device The radial dimension is enlarged. However, downsizing of the device is strongly desired as a major premise in the design of this type of device.
Therefore, the present invention broadens the resonance frequency region by the damping orifice in the low frequency region to expand the high attenuation region, and absorbs the internal pressure fluctuation in the main liquid chamber in the region higher than the resonance frequency region. The purpose is to realize a dynamic spring and to simplify the structure of the entire apparatus and make it compact at the same time.

In order to solve the above problems, the invention described in claim 1 divides a liquid chamber surrounded by an insulator and a diaphragm into a main liquid chamber and a sub liquid chamber by a partition member, and the main liquid chamber and the sub liquid chamber communicate with each other. A first damping orifice that resonates in a liquid column in a low frequency range below a predetermined frequency and a second damping orifice that resonates at a frequency higher than the resonance frequency of the first damping orifice are provided, and the main liquid chamber is provided in the partition member. In a liquid seal vibration isolator provided with an elastic film that is elastically deformed in response to fluctuations in internal pressure,
The elastic membrane comprises a resonance elastic membrane that covers the opening of the second damping orifice and contributes to the generation of damping force, and an internal pressure absorbing portion film that absorbs internal pressure fluctuations in the main liquid chamber,
The resonance elastic membrane and the internal pressure absorbing portion membrane are arranged so that each part thereof overlaps in the vibration input axis direction, and
The resonance elastic membrane (11) and the internal pressure absorbing portion membrane (12) each have a non-circular shape .

A second aspect of the present invention is characterized in that, in the first aspect , the resonance elastic film and the internal pressure absorbing portion film are offset to opposite sides with respect to the center of the partition member.

The invention described in claim 3, Oite to any preceding claim 1 or 2, in the partition member, together with facing to the main liquid chamber, communicating to the auxiliary liquid chamber through the second damping orifice An intermediate liquid chamber,
The intermediate liquid chamber is partitioned from the main liquid chamber side by the elastic film for resonance.

According to a fourth aspect of the present invention, in the third aspect of the invention, the second damping orifice surrounds the inner pressure absorbing portion film.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the resonance elastic membrane and the internal pressure absorbing portion film are provided separately.

A sixth aspect of the present invention is characterized in that, in the fifth aspect , the resonance elastic film and the internal pressure absorbing portion film are the same .

According to the first aspect of the present invention, the first damping orifice and the second damping orifice are provided, and the hydraulic fluid for the second damping orifice is pressurized with the resonance elastic film, thereby causing two resonances with low frequency large amplitude vibration. Thus, the resonance region can be broadened.
Moreover, the internal pressure absorbing portion film can be elastically deformed by high-frequency small-amplitude vibrations to absorb internal pressure fluctuations in the main liquid chamber, thereby reducing the dynamic spring.

In addition, the elastic film is composed of a separate elastic film for resonance and an internal pressure absorbing part film, and these are arranged so that they partially overlap in the vibration input direction, so that the entire device is not widened and the entire device is compact. Can be. In addition, it is possible to increase the pressure receiving area by making the elastic elastic film and the internal pressure absorbing portion film large in area.

Further, since the resonance elastic membrane and the pressure absorbing unit film was respectively noncircular shape, even if each of the pressure receiving area is sufficiently secured, it is possible to reduce the overlap, moreover, prevent the spread of the whole device be able to.

According to the second aspect of the present invention, since the resonance elastic membrane and the internal pressure absorbing portion membrane are offset to the opposite sides with respect to the center of the partition member, they can be arranged so as to reduce the overlap of the pressure receiving surfaces.

According to the invention of claim 3 , since the intermediate liquid chamber that communicates with the second damping orifice is provided, and the resonance elastic film is provided in the intermediate liquid chamber, the pressure receiving area of the resonance elastic film is sufficiently increased, The resonance efficiency of the second damping orifice can be increased.

According to the invention of claim 4 , since the second damping orifice is provided so as to surround the inner pressure absorbing portion film, a sufficient length can be secured so that a part thereof overlaps the resonance elastic film in the vibration input axis direction. In addition, the partition member can be prevented from becoming large.

According to the fifth aspect of the present invention, since the elastic film is composed of the separate elastic film for resonance and the internal pressure absorbing part film, the elastic film can be functionally differentiated. In addition, since the elastic film for resonance and the internal pressure absorbing part film are separate bodies, the elastic films having different functions can be manufactured separately, which facilitates manufacture. Furthermore, it is easy to change the degree of freedom of shape, material, etc., which is advantageous for improving functions.

According to the invention of claim 6 , since the elastic film is composed of the separate resonance elastic film and the internal pressure absorbing portion film, and these are the same, if only one type of relatively small elastic film is manufactured, Since it is good, the number of parts is reduced and manufacturing is facilitated.

Cross-sectional view of the entire engine mount according to the embodiment 2-2 sectional view of FIG. 3-3 sectional view of FIG. The figure which shows the overlap of the elastic membrane for resonance and the internal pressure absorption part membrane Figure exploded into parts Conceptual diagram of FIG. Dynamic characteristics graph Conceptual diagram of conventional example

Hereinafter, an embodiment configured as an engine mount will be described based on the drawings. 1-7 show an embodiment. 1 is an overall cross-sectional view, FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1, FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. FIG. 5 is an exploded view of components, and FIG. 6 is a conceptual diagram of FIG.
First, an outline will be described with reference to FIG. One end opening of the cylindrical second mounting member 2 is covered with an insulator 3, and the other end opening is covered with a diaphragm 4. Reference numeral 1 denotes a first mounting member.
Main vibration is input to the first mounting member 1 from the Z direction. The Z direction is parallel to the center axis CL of the mount.

The space surrounded by the second mounting member 2, the insulator 3 and the diaphragm 4 is a liquid chamber in which an incompressible hydraulic fluid such as water is enclosed, and this is divided into a main liquid chamber 6 and a sub liquid chamber by a partition member 5. Divide into 7. The partition member 5 is provided with a first damping orifice 8, which communicates with the main liquid chamber 6 and the sub liquid chamber 7 and is tuned so as to generate liquid column resonance at the time of shake vibration of low frequency large amplitude vibration. The vibration input having the frequency of clogging is clogged.

An elastic film 10 is provided on the partition member 5. In this example, the elastic film 10 is composed of a separate elastic film 11 for resonance and an internal pressure absorbing part film 12.
The resonance elastic film 11 has one surface facing the main liquid chamber 6 and the other surface facing the intermediate liquid chamber 13 formed between the sub liquid chamber 7 and is free to be elastically deformed even during large amplitude vibration. Is set. Reference numeral 24 denotes a deformation regulating rib, which regulates elastic deformation of the resonance elastic film 11 at an amplitude greater than or equal to the vibration with which the first damping orifice 8 resonates with a liquid column, and does not regulate elastic deformation with a large amplitude vibration having a smaller amplitude. It is like that.

The intermediate liquid chamber 13 communicates with the sub liquid chamber 7 through the second damping orifice 14. The second damping orifice 14 is set so as to resonate at a liquid column at a resonance frequency higher than that of the first damping orifice 8. However, the vibration in which the second damping orifice 14 resonates also belongs to the same low frequency and large amplitude vibration as the first damping orifice 8. Further, the second damping orifice 14 is clogged with respect to a vibration input having a frequency equal to or higher than the middle frequency, so that the resonance elastic film 11 is not elastically deformed.

The internal pressure absorbing portion film 12 covers the communication hole 15 that opens to the main liquid chamber 6 and the sub liquid chamber 7. The communication hole 15 is inserted so as to overlap with the lower part of the intermediate liquid chamber 13 in the vertical direction of the figure, and the internal pressure absorbing film 12 partially overlaps with the resonance elastic film 11 in the vertical direction. .
The elastic deformation of the internal pressure absorbing portion film 12 is set so that elastic deformation is restricted by the upper and lower deformation regulating ribs 34 and 44 with respect to medium amplitude and large amplitude vibration, and elastic deformation is free with respect to small amplitude vibration. Has been. That is, the resonance elastic film 11 is elastically deformable with large amplitude vibration, whereas the internal pressure absorbing film 12 is restricted so that elastic deformation is allowed only with small amplitude vibration.

One surface of the internal pressure absorbing portion film 12 faces the main liquid chamber 6 through the communication hole 15, and the other surface faces the sub liquid chamber 7 through the communication hole 15. The opening width of the communication hole 15 is sufficiently large so that it does not function as an orifice passage at least in the normal frequency range (for example, 500 Hz or less).

When the main vibration is input to the engine mount thus configured from the Z direction, the insulator 3 first absorbs the vibration.
Further, when the elastic deformation of the insulator 3 is applied to the main liquid chamber 6, the main liquid chamber 6 expands and contracts according to the elastic deformation of the insulator 3. In the case of low-frequency large-amplitude vibration, first, the hydraulic fluid flows between the main liquid chamber 6 and the sub liquid chamber 7 through the first damping orifice 8 to generate liquid column resonance (this is referred to as first resonance RS1). To do).

At this time, the elastic elastic film 11 is also restricted from elastic deformation, and the internal pressure absorbing part film 12 is also restricted from being deformed. Therefore, no hydraulic pressure is absorbed by the elastic elastic film 11 and the internal pressure absorbing part film 12. Since the liquid pressure in the main liquid chamber 6 is increased, the resonance efficiency in the first damping orifice 8 is increased. When the vibration input is slightly smaller in amplitude than the resonating large amplitude vibration of the first damping orifice 8 and slightly higher than the resonance frequency of the first damping orifice 8, the resonance elastic film 11 undergoes elastic deformation. Then, the hydraulic fluid in the intermediate liquid chamber 13 is pushed and pulled, the hydraulic fluid flows between the intermediate liquid chamber 13 and the auxiliary liquid chamber 7 via the second damping orifice 14, and the liquid column resonance by the second damping orifice 14 is caused. Occurs (this will be referred to as a second resonance RS2).

When the second resonance RS2 is generated, the first damping orifice 8 starts to be clogged, and the internal pressure absorbing portion film 12 is continuously restricted from elastic deformation, and the hydraulic fluid flowing through the second damping orifice 14 is In addition to the spring force of the insulator 3, the resonance elastic film 11 is flowed with a higher spring force applied with the spring force of the resonance elastic film 11, so that the resonance efficiency of the second resonance RS 2 is also increased.

The first resonance RS1 and the second resonance RS2 belong to a low frequency range, respectively, and the resonance frequency of the second resonance RS2 is slightly higher than that of the first resonance RS1.
Accordingly, two resonances of the first resonance RS1 and the second resonance RS2 occur in the low frequency region, and the resonance region is broadened by leveling between the two resonances and expanding the frequency region in the high attenuation state. It will become.

At the time of inputting medium frequency medium amplitude vibration and high frequency small amplitude vibration, the first damping orifice 8 and the second damping orifice 14 are clogged. Therefore, since the resonance elastic film 11 is not elastically deformed, it does not participate in internal pressure absorption, and only the internal pressure absorbing film 12 is elastically deformed to absorb the internal pressure of the main liquid chamber 6 and contribute to the reduction of the dynamic spring. That is, the elastic film for resonance 11 is allowed to be elastically deformed only for resonance at the second damping orifice 14 and does not have an action of absorbing internal pressure.

Further, since the resonance elastic film 11 and the internal pressure absorbing film 12 are formed separately from each other and partially overlap each other in the direction of the central axis CL, the diameter of the partition member 5 is greatly increased. It can be arranged without. As a result, the width W of the engine mount becomes smaller than the case where the resonance elastic film 11 and the internal pressure absorbing portion film 12 are simply arranged side by side, and the entire engine mount can be made compact accordingly.

FIG. 7 is a graph of the dynamic characteristics of the engine mount. A is a dynamic spring characteristic when the vibration is applied with an amplitude of ± 1.0 mm belonging to the large amplitude region, and B is a damping characteristic under the same conditions. In this graph, in the comparative example, the second damping orifice 14 is omitted, and the elastic film is made large so that the resonance elastic film 11 and the internal pressure absorbing film 12 are integrated.

In the comparative example thus configured, the dynamic spring curve becomes maximum at about 14 Hz, and the attenuation curve becomes maximum at 10 Hz. The maximum part of the damping curve shows the occurrence of liquid column resonance due to the damping orifice, and the maximum part of the dynamic spring curve shows the anti-resonance. Therefore, it is shown that only one liquid column resonance is generated by only one damping orifice in the low frequency region in this graph.
Thus, when there is only one liquid column resonance, the resonance region is relatively narrow, and due to anti-resonance, the dynamic spring is relatively high and the damping is low at a portion above 20 Hz.

On the other hand, according to the present invention, in the attenuation curve, there is a first maximum due to the first resonance indicated by RS1 at about 9 Hz, and a second maximum due to the second resonance indicated by RS2 at about 22 Hz. In the dynamic spring curve, there is a first maximum due to anti-resonance of the first resonance at about 13 Hz, and a second maximum due to anti-resonance of the second resonance at about 25 Hz. For this reason, by generating two liquid column resonances at different frequencies in the low frequency range, a relatively low dynamic spring is formed between the first resonance and the second resonance by the respective interactions, and the damping is relatively Keep high.

As a result, at 5 to 20 Hz, it means a low dynamic spring and high damping, and the resonance region is broadened. Therefore, in a low frequency large amplitude vibration, it is possible to generate two liquid column resonances to broaden the resonance region, and to provide an excellent liquid seal vibration isolator that realizes the necessary high damping and sufficient low dynamic springs. Can be obtained.

Although not clear from this graph, when the vibration input becomes a frequency higher than the medium frequency, the liquid column resonance due to the damping orifice does not occur, and instead the internal pressure of the main liquid chamber 6 is increased by the internal pressure absorbing portion film 12. Because it is absorbed, it becomes a low dynamic spring.

Next, a specific example of the embodiment will be described based on FIGS. 1 is a cross-sectional view corresponding to FIG. 6 taken along the central axis CL of the engine mount in parallel with the main vibration input direction Z, FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1, and FIG. 1 is a cross-sectional view taken along line 3-3, FIG. 4 is a view showing the overlap of the resonance elastic film 11 and the internal pressure absorbing film 12, and FIG. 5 is an exploded view showing components of the partition member.

FIG. 5 is a view showing both a cross section of the partition member 5 in FIG. 1 and a perspective view showing each component part from above. As shown in this figure, the partition member 5 is composed of an upper member 20, an intermediate member 30, and a lower member 40 that are divided into upper and lower parts. The upper member 20, the middle member 30, and the lower member 40 each have a disk shape in a plan view, the upper member 20 is made of metal, and the middle member 30 and the lower member 40 are each made of a suitably rigid material such as a thick resin. It is the member which consists of.

The upper member 20 is formed so that a substantially quadrangular first opening 21 and a semicircular second opening 22 face each other, and the main liquid chamber side opening of the first damping orifice 8 is formed at an edge portion in the vicinity of the second opening 22. 23 is provided. The first opening 21 is formed by making one side of the quadrilateral into an arc shape parallel to the outer peripheral portion of the upper member 20, and in the present application, such a shape is referred to as a substantially quadrilateral shape.

The first opening 21 communicates with the intermediate liquid chamber 13 and is provided with a deformation restriction rib 24 having a cross shape in plan view on the upper side. When the partition member 5 is assembled, the first opening 21 overlaps with the resonance elastic film 11 to resonate. 11 excessive deformation is regulated. The second opening 22 communicates with the communication hole 15.

The middle member 30 is provided with an intermediate liquid chamber 13 and an upper hole 33 having a substantially quadrilateral shape in plan view corresponding to the first opening 21 and the second opening 22 of the upper member 20. The intermediate liquid chamber 13 is a bottomed recess, and an intermediate liquid chamber side opening 32 of the second attenuation orifice 14 is formed at the bottom of the intermediate liquid chamber 13.
An annular groove 31 is provided around the intermediate liquid chamber 13, and an edge 11 a formed around the outer peripheral portion of the resonance elastic film 11 is fitted therein.
The opening edge in the plan view of the intermediate liquid chamber 13 includes a linear portion 13a substantially corresponding to the diameter of the intermediate member 30, an arc portion 13b facing the parallel portion 13 and parallel to the outer peripheral portion of the intermediate member 30, and a linear portion 13a. It consists of a pair of straight portions 13c that are parallel to each other and that are relatively short, connecting both ends of the arc portion 13b.

The upper hole 33 has a substantially straight through hole shape in the vertical direction, and constitutes the communication hole 15 together with the lower hole 43 of the lower member 40 described later.
A cross-shaped deformation restriction rib 34 is provided at the bottom of the upper hole 33 to restrict large deformation of the internal pressure absorbing portion film 12 when large amplitude vibration is input, and an annular groove 35 is provided on the bottom surface to absorb internal pressure. The edge portion 12a provided around the outer peripheral portion of the partial film 12 can be fitted.

Around the upper surface side of the middle member 30, an upper first orifice groove 36 is formed to open upward in a substantially semicircular arc shape so as to surround the opening of the upper hole 33. The upper first orifice groove 36 corresponds to a part of the first damping orifice 8 and is an arc-shaped groove opened upward.
One end 36 a of the upper first orifice groove 36 forms an opening on the main liquid chamber side that is enlarged on the side of the resonance elastic film 11, and the other end 36 b is on the opposite side of the one end 36 a with the intermediate liquid chamber 13 interposed therebetween. To position.

The lower member 40 is provided with a lower hole 43 having a semicircular shape in plan view that coincides with the upper hole 33 in the vertical direction. The lower hole 43 has a straight line portion 43 a extending in the diameter direction of the lower member 40 and a circular arc portion 43 b that forms a semicircular shape along the outer peripheral portion of the lower member 40 from both ends thereof.

A cross-shaped deformation restricting rib 44 is provided at the bottom of the lower hole 43 to restrict large downward deformation when the internal pressure absorbing portion film 12 is input with large amplitude vibration. Around the bottom portion, an annular groove 45 that fits the lower outer peripheral portion of the edge portion 12a of the internal pressure absorbing portion film 12 is provided.
A portion below the intermediate liquid chamber 13 forms a flat portion 41 where one end 42a of the second orifice groove 42 forming the second damping orifice 14 is located and communicates with the opening 32.

The second orifice groove 42 is formed so as to open upward so as to surround the lower hole 43, and one end 42 a is located at the center of the flat portion 41, and extends substantially along the straight portion 43 a of the lower hole 43 from here. The lower member 40 extends radially outward, further extends in an arc shape along the outer side of the arc portion 43b of the lower hole 43, and the other end 42b is surrounded by the second orifice groove 42 at both ends of the linear portion 43a. It is located in the vicinity of the other end opposite to the one end. Here, the lower member 40 is opened through the lower member 40 and communicated with the auxiliary liquid chamber 7.

A lower first orifice groove 46 that forms the lower portion of the first damping orifice 8 is formed on the outer periphery of the flat portion 41 so as to open upward. The lower first orifice groove 46 is formed in a substantially ¼ arc shape, and one end 46 a thereof is located in the vicinity of the lower hole 43 and in the vicinity of the other end 42 b of the second orifice groove 42.
The other end 46b of the lower first orifice groove 46 is disposed so as to overlap one end 42a of the second orifice groove 42 in the radially outward direction of the lower member 40, and further penetrates the lower member 40 downward and opens. The sub-liquid chamber 7 is communicated.

The resonance elastic film 11 has a substantially quadrangular shape in a plan view, is made of an appropriate elastic body such as rubber, and includes a thick edge portion 11a formed around and a main body portion 11b surrounded by the edge portion 11a. By fitting the edge portion 11 a into the annular groove 31, the main body portion 11 b covers the upper portion of the intermediate liquid chamber 13 and is elastically deformed due to a change in the internal pressure of the main liquid chamber 6.
The edge portion 11 a includes a linear portion 11 c and an arc portion 11 d that are parallel to the linear portion 13 a and the arc portion 13 b at the opening edge portion of the intermediate liquid chamber 13. In addition, a pair of straight portions parallel to the pair of short straight portions 13c is provided.

The internal pressure absorbing portion film 12 has a substantially semicircular shape in plan view, and has a thick and rigid edge portion 12a formed around it, and is surrounded by the edge portion 12a and is thinner and elastically deformed than the edge portion 12a. And a main body 12b that absorbs the internal pressure of the main liquid chamber 6.

The edge portion 12a includes a linear portion 12c and an arc portion 12d that are parallel to the linear portion 43a and the arc portion 43b of the lower hole 43, respectively. Further, a plurality of ribs 12e are formed to protrude from the body portion 12b of the internal pressure absorbing portion film 12 surrounded by the arc portion 43b of the lower hole 43, thereby adjusting the rigidity of the internal pressure absorbing portion film 12 against elastic deformation.

When the edge portion 12 a is fitted into the annular groove 35 and the annular groove 45, the periphery of the internal pressure absorbing portion film 12 is fixed by the middle member 30 and the lower member 40, and the edge portion 12 a forms a fixing portion for the partition member 5. Since the edge portion 12a is fixed by the middle member 30 and the lower member 40, the main body portion 12b is supported between the upper hole 33 and the lower hole 43 in an elastically deformable state, and closes the communication hole. 15 is to be closed.

In order to assemble the partition member 5, first, the edge 12 a of the internal pressure absorbing portion film 12 is fitted into the annular groove 45 of the lower member 40, and then the intermediate member 30 is stacked thereon, and the internal pressure absorbing portion film is overlapped with the annular groove 35. Twelve edge portions 12a are fitted.
Subsequently, the edge 11 a of the elastic elastic film 11 is fitted into the annular groove 31 around the intermediate liquid chamber 13, and the upper member 20 is overlaid thereon, and is formed around the first opening 21 portion of the upper member 20. The annular rib 25 is fitted to the inner side of the edge portion 11a, and the upper member 20, the middle member 30, and the lower member 40 as a whole are integrated by an appropriate method.

As a result, the lower first orifice groove 46 is closed at the bottom of the middle member 30 except for both ends 46a and 46b, and one end 46a overlaps the other end 36b of the upper first orifice groove 36 in the vertical direction. The end 46 b opens toward the sub liquid chamber 7.
The upper first orifice groove 36 is also continuously arranged in two upper and lower stages in the partition member 5 by closing the opening except for both ends with the upper member 20 and communicating with the lower first orifice groove 46 at the other end 36b. The first damping orifice 8 is configured. One end 36 a of the upper first orifice groove 36 overlaps with the main liquid chamber side opening 23 of the upper member 20 and communicates with the main liquid chamber 6 through the main liquid chamber side opening 23.

The second orifice groove 42 is closed at the bottom of the middle member 30 except for both end portions 42 a and 42 b, and the inside becomes the second damping orifice 14. Since one end portion 42a of the second orifice groove 42 communicates with the intermediate liquid chamber 13 and the other end portion 42b opens toward the sub liquid chamber 7, the second damping orifice 14 has the intermediate liquid chamber 13 and the sub liquid chamber. Communicate to 7

The resonance elastic film 11 faces the main liquid chamber 6 through the first opening 21 with the upper surface facing upward, and the lower surface faces the intermediate liquid chamber 13. Further, the deformation restricting rib 24 is disposed above the first opening 21 with a relatively large distance from the resonance elastic film 11 to enable free elastic deformation even during large amplitude vibration.

For this reason, in response to a change in the internal pressure in the main liquid chamber 6, it is elastically deformed, causing the working fluid to move between the intermediate liquid chamber 13 and the sub liquid chamber 7 via the second damping orifice 14, and a predetermined low frequency A liquid column resonance is generated in the second damping orifice 14 in the region.
When excessive vibration greater than a predetermined large-amplitude vibration is input, the deformation restricting rib 24 closes the elongated elastic elastic film 11 to the deformation restricting rib 24 to prevent excessive elastic deformation, thereby causing the elastic elastic film for resonance. 11 is provided to prevent breakage of 11.

The upper hole 33 and the lower hole 43 overlap with each other to form the communication hole 15, but the communication hole 15 is blocked by the inner pressure absorbing portion film 12 at the intermediate portion and is not in communication. The upper hole 33 overlaps the second opening 22 of the upper member 20 and is opened toward the main liquid chamber 6. Therefore, the upper surface of the internal pressure absorbing portion film 12 faces the main liquid chamber 6 and receives a change in internal pressure in the main liquid chamber 6.
The lower hole 43 is opened toward the secondary liquid chamber 7, and the lower surface of the internal pressure absorbing portion film 12 faces the secondary liquid chamber 7.

Since the internal pressure absorbing portion film 12 is provided with the deformation restricting ribs 34 and 44 on the upper and lower sides, at the time of a predetermined large amplitude vibration, the internal pressure absorbing portion film 12 is pressed against the deformation restricting rib 34 or 44 by a predetermined extension to restrict elastic deformation. However, if the vibration has a smaller amplitude than the large amplitude vibration, the vibration is not restricted by the deformation restriction ribs 34 and 44, and is freely elastically deformed. For this reason, the working fluid inside the upper hole 33 can freely move between the main fluid chamber 6 through the second opening 22.
Further, the hydraulic fluid inside the lower hole 43 can freely move between the sub liquid chamber 7.

In the partition member 5 assembled in this way, as shown in FIG. 1, the resonance elastic membrane 11 and the internal pressure absorbing portion membrane 12 partially overlap in the vertical direction (the direction indicated by the arrow Z). . As shown in detail in FIG. 4, when the top, bottom, left, and right and front and rear are illustrated in the top view shown in A, the respective straight portions 11 c and 12 c overlap each other at the overlap margin D. However, as shown in side view B, they are shifted in the front-rear direction and overlapped by an overlap margin D.

On the other hand, as shown in C, when viewed from the front-rear direction (rear side in this example), they overlap symmetrically, and there is no shift in the left-right direction. For this reason, the front-rear width W1 and the left-right width W2 can be made substantially equal.
Therefore, the elastic membrane 10 is compact in spite of having a total membrane area of the resonance elastic membrane 11 and the internal pressure absorbing portion membrane 12, and is a second attachment having a relatively small diameter cylindrical shape. It can be accommodated inside the member 2.

Next, the vibration isolating action of this engine mount will be described. First, when low-frequency large-amplitude vibration is input, the main liquid chamber 6 expands and contracts due to elastic deformation of the insulator 3. As a result, the hydraulic fluid flows between the main liquid chamber 6 and the sub liquid chamber 7 via the first damping orifice 8 and generates liquid column resonance (first resonance) in the first damping orifice 8. At this time, since the elastic film 11 for resonance and the internal pressure absorbing film 12 are restricted from elastic deformation, the resonance efficiency of the first resonance is increased.

Thereafter, when the input vibration becomes slightly higher than the resonance frequency of the first resonance and the amplitude becomes small, the first damping orifice 8 is clogged and the resonance elastic film 11 facing the main liquid chamber 6 is elastically deformed. As a result, the intermediate liquid chamber 13 expands and contracts, and the hydraulic fluid flows between the intermediate liquid chamber 13 and the sub liquid chamber 7 via the second damping orifice 14, and the liquid column resonance (second resonance) occurs in the second damping orifice 14. ). Since the first resonance and the second resonance have different resonance frequencies in the same low frequency range, the dynamic characteristics shown in FIG. 7 are exhibited, and the resonance range in the low frequency range is achieved by the first resonance and the second resonance. Broaden.

When the second resonance occurs, the internal pressure absorbing film 12 is not elastically deformed by the deformation regulating rib 34 and the deformation regulating rib 44 due to the large amplitude vibration. The flow of hydraulic fluid to the first damping orifice 8 and the second damping orifice 14 can be made good, and the resonance efficiency can be increased.

Further, since the hydraulic fluid in the intermediate liquid chamber 13 is pushed by a large spring force in which the resonance elastic film 11 and the insulator 3 are combined, the resonance efficiency of the second damping orifice 14 can be increased.

Thereafter, during the medium frequency medium amplitude vibration and the high frequency small amplitude vibration, the first damping orifice 8 and the second damping orifice 14 are clogged, and the flow in these stops, but the internal pressure fluctuation in the main liquid chamber 6 is the internal pressure absorbing portion. The film 12 is absorbed by elastic deformation. At this time, the elastic elastic film 11 does not elastically deform due to the clogging of the second damping orifice 14. Further, the internal pressure absorbing portion film 12 is restricted from large deformation by the upper and lower deformation restriction ribs 34 and the deformation restriction ribs 44, but can be elastically deformed freely by medium amplitude vibration and small amplitude vibration, and the internal pressure of the main liquid chamber 6 can be reduced. Absorbs well.

As described above, the internal pressure absorbing portion film 12 is separated from the resonance elastic membrane 11 and is disposed so as to partially overlap with each other. Therefore, it is necessary to ensure a sufficiently large film area of the internal pressure absorbing portion film 12. The internal pressure can be absorbed and the entire engine mount device can be made compact.

In addition, since the elastic film 10 is composed of the separate resonance elastic film 11 and the internal pressure absorbing film 12, the elastic film 10 can be functionally differentiated. In addition, since the resonance elastic film 11 and the internal pressure absorbing film 12 are separate bodies, elastic films having different functions can be manufactured separately, which facilitates manufacture. Furthermore, it is easy to change the degree of freedom of shape, material, etc., which is advantageous for improving the function.

In addition, the elastic film 10 is composed of the separate resonance elastic film 11 and the internal pressure absorbing part film 12, and these are arranged so as to partially overlap in the vibration input direction. The whole can be made compact. In addition, it is possible to increase the pressure receiving area by making the resonance elastic film 11 and the internal pressure absorbing film 12 wide.

In addition, since the resonance elastic film 11 and the internal pressure absorbing portion film 12 are each formed into a non-circular irregular shape, even if each pressure receiving area is sufficiently secured, the overlap can be reduced, and the entire apparatus is enlarged. Can be prevented.

Furthermore, since the resonance elastic film 11 and the internal pressure absorbing film 12 are offset to the opposite sides with respect to the center of the partition member 5, they can be arranged so as to reduce the overlap of the pressure receiving surfaces.

In addition, since the elastic membrane 10 is composed of the separate resonance elastic membrane 11 and the internal pressure absorbing portion membrane 12 and they are the same, only one type of relatively small elastic membrane needs to be manufactured. The number of points is reduced, and manufacturing becomes easy.

In addition, since the intermediate liquid chamber that communicates with the second damping orifice 14 is provided and the resonance elastic film 11 is provided in the intermediate liquid chamber, the pressure receiving area of the resonance elastic film 11 is sufficiently increased, so that the second damping orifice is obtained. The resonance efficiency of 14 can be increased.

In addition, since the second damping orifice 14 is provided so as to surround the inner pressure absorbing portion film 12, a sufficient length can be secured so that a part thereof overlaps the resonance elastic membrane 11 in the vibration input axis direction, and the partition member 5 can be set not to increase.

The present invention is not limited to the above-described embodiments, and various modifications and applications are possible within the principle of the invention. For example, in place of the engine mount, the present invention can be applied to various liquid seal vibration isolators for suspension and the like .

3: Insulator, 5: Partition member, 6: Main liquid chamber, 7: Sub liquid chamber, 8: First damping orifice, 10: Elastic film, 11: Resonant elastic film, 12: Internal pressure absorbing part film, 13: Intermediate Liquid chamber, 14: second damping orifice

Claims (6)

A liquid chamber surrounded by the insulator (3) and the diaphragm (4) is divided into a main liquid chamber (6) and a sub liquid chamber (7) by a partition member (5), and the main liquid chamber (6) and the sub liquid chamber ( 7), a first damping orifice (8) that resonates in a liquid column in a low frequency range below a predetermined frequency, and a second damping orifice that resonates at a higher frequency than the resonance frequency of the first damping orifice (8). In the liquid seal vibration isolator provided with (14), and further provided with an elastic film elastically deforming according to the internal pressure fluctuation of the main liquid chamber (6) on the partition member (5),
The elastic membrane covers the opening of the second damping orifice (14) and contributes to the generation of damping force, and the resonance elastic membrane (11) and the internal pressure absorbing portion that absorbs internal pressure fluctuations in the main liquid chamber (6). Composed of a membrane (12),
The resonance elastic membrane (11) and the internal pressure absorbing portion membrane (12) are arranged so that each part thereof overlaps in the vibration input axis direction ,
The liquid seal vibration isolator, wherein the resonance elastic membrane (11) and the internal pressure absorbing portion film (12) each have a non-circular shape . The liquid according to claim 1, wherein the resonance elastic membrane (11) and the internal pressure absorbing portion membrane (12) are offset to opposite sides with respect to the center of the partition member (5). Seal vibration isolator. The partition member (5) is provided with an intermediate liquid chamber (13) that faces the main liquid chamber (6) and communicates with the sub liquid chamber (7) through the second damping orifice (14).
Ekifubofu the intermediate liquid chamber (13), by the resonant elastic membrane (11), as claimed in any one of claims 1 or 2, characterized in that the partition between the main liquid chamber (6) side apparatus. The liquid seal vibration isolator according to claim 3 , wherein the second damping orifice (14) surrounds the inner pressure absorbing portion film (12). The liquid seal vibration isolator according to any one of claims 1 to 4 , wherein the resonance elastic membrane (11) and the internal pressure absorbing portion film (12) are provided separately. The liquid seal vibration isolator according to claim 5 , wherein the resonance elastic membrane (11) and the internal pressure absorbing portion film (12) are the same .

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