JPH03113141A - Fluid seal type cylindrical mount device - Google Patents

Abstract

PURPOSE:To secure the superior vibrationproof characteristic for the input vibration over a wide frequency range by restricting the flow of fluid through a communication passage between fluid chamber by regulating the deformation of a flexible film ar ranged in the communication passage through the contact with the inner surface of the communication passage, when a low frequency vibration having a large width is inputted. CONSTITUTION:As a partitioning member 46 is arranged in a second peripheral groove 35, the inside of the second peripheral groove 35 is partitioned into an inside part 52 and an outside part 54 in the radial direction of a mount by a rubber elastic film 50, and the inside part 52 is opening-connected to a first pocket part 20 side, and an outside part 54 is opening-connected to a second pocket part 24 side. Inside the first and second pocket parts 20 and 24, a first and second fluid chamber 58 and 60 in which the vibration inputted into between the inner and outer cylindrical metal fittings 10 and 12 is applied and each relative internal pressure difference is generated on the basis of the elastic deformation of a rubber elastic body 14 are formed. Inside the first fluid chamber 58, the periphery of a movable block 56 is made narrow by arranging the movable block 56 at an intermediate position, and a vibration action part is formed.

Description

Detailed Description of the Invention (Technical Field) The present invention relates to a cylindrical fluid-filled mount device that dampens input vibration based on the flow of fluid sealed inside.
In particular, the present invention relates to a fluid-filled cylindrical mount device that can effectively exhibit a vibration damping effect based on fluid flow against input vibrations over a wide frequency range.

(Background Art) Conventionally, vibration transmission systems have been interposed between members that constitute vibration transmission systems.
As a type of mounting device that connects these two members in a vibration-proof manner, an inner cylindrical metal fitting and an outer cylindrical metal fitting arranged outside the inner cylindrical metal fitting at a predetermined distance are connected to each other by a rubber elastic material interposed between them. A so-called cylindrical mount device is known, which has a structure in which the body is integrally connected and is designed to mainly dampen radial vibration input between an inner and outer cylindrical metal fitting. In addition, with such a cylindrical mount device, it is possible to advantageously realize a compact mount size, and the relative displacement amount of the inner and outer cylindrical metal fittings when an excessive vibration load is input can be advantageously regulated. For this reason, it has been suitably used as, for example, automobile engine mounts, differential mounts, suspension bushings, and the like.

In addition, in recent years, as shown in Japanese Patent Application Laid-open No. 56-164242 and Japanese Patent Application Laid-open No. 63-289349, an orifice has been added between the inner cylinder fitting and the outer cylinder fitting in such a cylindrical mount device. The so-called so-called structure has a structure in which a plurality of fluid chambers are formed that communicate with each other through passages, and when vibration is input between the inner and outer cylindrical metal fittings, fluid flows between the fluid chambers through such orifice passages. A fluid-filled cylindrical mount device has been proposed, and based on the resonance effect of the fluid flowing inside the orifice passage, it is possible to obtain an excellent vibration damping effect that cannot be obtained with rubber elastic bodies alone. Recruitment is increasing.

However, in such a fluid-filled cylindrical mount device, the effect of improving vibration damping characteristics due to the resonance effect of the fluid is only effective against input vibration in a limited frequency range set in the orifice passage. For this purpose, for example, if the orifice passage is tuned so that a high damping effect based on the resonance effect of the fluid can be exhibited when vibration is input in the low frequency range corresponding to shake or bounce. When a vibration is input in a frequency range higher than the tuning frequency, the orifice passage becomes substantially blocked, causing the mount to have a high spring movement, resulting in medium to high-frequency sound corresponding to muffled noise, etc. The problem was that the vibration isolation performance against input vibration in the frequency range was significantly reduced.

(Problem to be solved) Here, the present invention has been made against the background of the above-mentioned circumstances, and the problem to be solved is:
While ensuring a sufficient vibration damping effect based on the resonance effect of the fluid flowing in the orifice passage, the mount is reduced or prevented from becoming highly dynamic when a vibration is input in a frequency range higher than the resonance frequency of the fluid. It is an object of the present invention to provide a fluid-filled cylindrical mount device that can be used in a wide range of frequencies and exhibit good vibration isolation performance against input vibrations in a wide frequency range.

(Solution Means) In order to solve this problem, the present invention includes an inner cylindrical metal fitting and an outer cylindrical metal fitting that are arranged at a predetermined distance in the radial direction, and a cylindrical metal fitting that is interposed between them. A plurality of fluid chambers each filled with a predetermined incompressible fluid are formed between the inner and outer cylindrical metal fittings, which are connected by a rubber elastic body, and in which a relative internal pressure change occurs when vibration is input. In the fluid-filled cylindrical mount device, the fluid-filled cylindrical mount device is provided with an orifice passage that communicates the fluid chambers with each other, and the communication passage that spans between the fluid chambers and extends in the circumferential direction between the inner and outer cylindrical fittings is independent of the orifice passage. and a flexible membrane located within the communication passageway, extending along the inner surface of the communication passageway, and partitioning the inside of the communication passageway into a substantially inner portion and an outer portion in the radial direction of the mount. Further, the inner portion and the outer portion are configured to communicate with the different fluid chambers so that the internal pressure of the fluid chambers is applied to both sides of the flexible membrane. That is.

(Examples) Hereinafter, in order to clarify the present invention more specifically, examples of the present invention will be described in detail with reference to the drawings.

First, FIGS. 1 to 4 show a specific example of the present invention applied to an engine mount for an automobile. In these figures, reference numeral 10 denotes an inner cylindrical metal fitting, on the outside of which an outer cylindrical metal fitting 12 is arranged eccentrically by a predetermined amount, and a rubber elastic body interposed between the inner and outer cylindrical metal fittings 10 and 12. 14, they are integrally connected.

In this engine mount, the inner cylindrical metal fitting 10 and the outer cylindrical metal fitting 12 are attached to either the vehicle body side or the engine unit side, so that the engine unit is supported with vibration isolation against the vehicle body. ing.

In addition, regarding the engine mount in this example,
When the engine unit is installed between the engine unit and the vehicle body, the weight of the engine unit causes the inner cylinder fitting 10 to be positioned approximately concentrically with respect to the outer cylinder fitting 12. Under these conditions, the main vibration is input in the vertical direction in FIG.

More specifically, the inner cylindrical fitting 10 has a thick-walled cylindrical shape, and a metal sleeve 16 having a thin-walled cylindrical shape is arranged eccentrically by a predetermined dimension on the radially outer side thereof.

As shown in FIGS. 5 and 6, the rubber elastic body 14, which has a substantially thick-walled cylindrical shape as a whole, is interposed between the inner cylindrical fitting 10 and the metal sleeve 16. The rubber elastic body 14 is formed as an integrally vulcanized molded product 18 that is vulcanized and bonded to the outer circumferential surface of the inner cylinder fitting IO and the inner circumferential surface of the metal sleeve 16, respectively.

In addition, the rubber elastic body 1 constituting this integrally vulcanized molded product 18
4 is provided with a first pocket portion 20 on the side where the distance between the inner cylinder fitting 10 and the metal sleeve 16 is larger in the eccentric direction, and a first window portion 22 provided in the metal sleeve 16 The outer peripheral surface is opened through the opening.

Furthermore, the inner cylinder fitting 10 in such a rubber elastic body 14
A second pocket portion 24 is formed on the side where the distance between the metal sleeve 16 and the metal sleeve 16 is smaller.
It is opened to the outer peripheral surface through a second window section 25 provided in the.

Further, the bottom wall portion of the second pocket portion 24 made of the rubber elastic body 14 is externally fitted and fixed to the inner cylindrical fitting 10 at the center portion thereof, so that the second pocket portion 24 side A connecting fitting 26 protruding from the bottom wall is embedded and integrally bonded by vulcanization, and a predetermined depth is formed in the axial direction from both axial end surfaces of the rubber elastic body 14 on both axially side portions of the bottom wall. A pair of recesses 28, 28 are formed that extend from each other.

The hollow portions 28.28 reduce the tensile stress generated in the rubber elastic body 14 due to the weight of the engine unit when the mount is attached, so that the durability of the rubber elastic body 14 can be advantageously ensured. It has become. The protruding end portion of the connecting fitting 26 is positioned to protrude at a predetermined height into the second pocket portion 24, and the buffer rubber 30 having a predetermined thickness is provided on the protruding end surface, so that the stopper portion 32 It is configured as.

On the other hand, in the metal sleeve 16, the central portion in the axial direction is reduced in diameter to form a small diameter portion 42, and the first window portion 22 and the second window portion 42 are formed in the small diameter portion 42. A first circumferential groove 34 and a second circumferential groove 35 are formed, respectively, extending between both end portions of the window portion 25 in the circumferential direction and connecting both the window portions 22.25. Furthermore, thin seal rubber IJ36 is integrally formed with the rubber elastic body 14 on the outer peripheral surface of each of the large diameter portions 44, 44 on both sides in the axial direction of the metal sleeve 16.

Further, in the integrally vulcanized molded product 18 having such a structure, the metal sleeve 16 is subjected to a diameter reduction process as required, so that the rubber elastic body 14 is pre-compressed, and then As shown in Figures 1 to 4,
A movable block 56 having an outer diameter smaller than that of the second pocket part 20 is displaceably accommodated in the first pocket part 20, and an orifice fitting 38 having a substantially semi-cylindrical shape is made of metal. Small diameter portion 42 of sleeve 16
By being fitted into the first pocket portion 24
It is assembled so as to straddle the 10th circumferential groove 34 from above the opening.

Here, in such orifice fitting 38,
As shown in FIG. 7, a groove 40 is provided on its outer circumferential surface in a meandering manner in the circumferential direction. , one end side of the groove 40 is connected to the inside of the first pocket part 20 through the through hole 41, while the other end side is connected to the second pocket part 24 through the -0th circumferential groove 34.
It is connected inside.

Furthermore, a partition member 46 is fitted and accommodated in the twenty-th circumferential groove 35 of the integrally vulcanized molded product 18. As shown in FIGS. 8 and 9, the partition member 46 includes a mounting bracket 48 having a substantially rectangular frame shape.
In contrast, a rectangular flat plate-shaped rubber elastic membrane 5 is provided inside the frame.
0 is arranged, and its outer peripheral edge is fixed to the inner peripheral surface of the mounting bracket 48.

In such a partition member 46, the 20th circumferential groove 3
5, the rubber elastic membrane 50 partitions the inside of the 20th circumferential groove 35 into an inner portion 52 and an outer portion 54 in the radial direction of the mount, and the inner portion 52 is separated from the first circumferential groove 35 by the rubber elastic membrane 50. The pocket portion 20 side is opened and the outer portion 54 is opened and connected to the second pocket portion 24 side.

Furthermore, these orifice fittings 38 and partition member 4
The outer cylindrical fitting 12 is inserted onto the outer peripheral surface of the integrally vulcanized molded product 18 to which the metal sleeve 6 is assembled, and the outer cylinder fitting 12 is fitted onto the outer peripheral surface of the metal sleeve 16. It is being

By fitting the outer cylinder fitting 12 outward, the openings of the first pocket part 20 and the second pocket part 24 are
Furthermore, the first and second pocket portions 20.24 are each filled with a predetermined incompressible fluid such as water, alkylene glycol, polyalkylene glycol, silicone oil, etc. , is enclosed. In addition, the enclosure of such a fluid is, for example,
This can be advantageously achieved by extrapolating the outer cylindrical fitting 12 to the integrally vulcanized molded product 18 in a predetermined fluid.

As a result, vibrations input between the inner and outer cylindrical fittings 10 and 12 are applied inside the first pocket portion 20 and the second pocket portion 24, and the vibration is caused by the elastic deformation of the rubber elastic body 14. A first fluid chamber 58 and a second fluid chamber 60 are respectively formed in which a relative internal pressure difference is generated.

Moreover, in the first fluid chamber 58,
By positioning the movable block 56 at a substantially intermediate position, the periphery of the movable block 56 is narrowed to form a vibration acting section. In this vibration acting section, when vibration is input between the inner and outer cylindrical fittings 10 and 12, a repeated flow of fluid is generated based on the deformation of the rubber elastic body 14. Based on the resonance effect, a predetermined vibration damping effect can be achieved. In addition, in this embodiment, due to the resonance effect of the fluid flowing in the vibration acting section, a low dynamic spring effect can be exerted when a high frequency vibration of about 200 to 3007, which corresponds to engine transmitted sound, is input. The gap, size, etc. are tuned accordingly.

Furthermore, in the second fluid chamber 60, a connecting fitting 2 is supported on the inner cylinder fitting 10 side and protrudes from the bottom wall side.
6 is positioned opposite to the inner circumferential surface of the outer cylindrical fitting 10 at a predetermined distance in the radial direction of the mount. Then, when a large vibration load is input between the inner and outer cylindrical fittings 10.12, the amount of relative displacement of the inner and outer cylindrical fittings 10.12 can be regulated by the abutment of the connecting fitting 26 against the outer cylindrical fitting 10. It has become.

Furthermore, the opening of the groove 40 in the orifice fitting 38 is closed by fitting the outer cylinder fitting 12 onto the integrally vulcanized molded product 18 . The first fluid chamber 58 and the second fluid chamber 60 are interconnected and the compartments 58 .
An orifice passage 62 is formed that allows fluid to flow between the two. In this embodiment, based on the resonance effect of the fluid flowing in the orifice passage 62, 101 corresponding to shake, bounce, etc.
Its length, flow path cross-sectional area, etc. are tuned so that it can exhibit a high damping effect when low-frequency, large-amplitude vibrations are input before and after processing.

Furthermore, the opening of the second circumferential groove 35 in the metal sleeve 16 is closed by fitting the outer cylindrical fitting 12 onto the integrally vulcanized molded product 18, and thereby, the opening of the second circumferential groove 35 in the metal sleeve 16 is closed. Said first fluid chamber 58f! - A communication passage 64 extending in the circumferential direction across the second fluid chamber 60 is formed independently of the orifice passage 62. Here, in the communication passage 64, the rubber elastic membrane 5 of the partition member 46 disposed inside the communication passage 64 is
an inner portion 52 communicating into a first fluid chamber 58 and an outer portion 54 communicating into a second fluid chamber 60 by
The fluid pressure in the first and second fluid chambers 58 and 60 can be applied to both sides of the rubber elastic membrane 50.

As a result, in the communication passage 64, when vibration is input between the inner and outer cylindrical fittings 10 and 12,
As the rubber elastic membrane 50 is deformed based on the internal pressure difference generated between the first and second fluid chambers 58, 60, substantial fluid flow between the two fluid chambers 58, 60 is prevented. Therefore,
By appropriately tuning the size etc. of this communication passage 64,
By utilizing the resonance effect or hydraulic pressure absorption effect caused by the flow of fluid flowing inside the mount, the mount can be used when high-frequency, small-amplitude vibrations such as muffled sounds are input that substantially block the orifice passage 62. This makes it possible to achieve a lower dynamic spring.

Furthermore, in the case of the rubber elastic membrane 50 disposed within the communication passage 64, as shown in FIG. Since the flow rate of the fluid between the first and second fluid chambers 58 and 60 through the communication passage 64 is restricted. And, in this example,
The amount of fluid flowing through the communication passage 64 absorbs the internal pressure difference between the first and second fluid chambers 58 and 60 that is caused when a low frequency, large amplitude vibration corresponding to a shake or the like is input. By setting the damping effect to such a low frequency and large amplitude vibration, the damping effect based on the resonance effect of the fluid flowing in the orifice passage 62 is tuned so that it can be effectively exerted. There is.

Therefore, in the engine mount having the above-described structure, the high damping effect against low-frequency, large-amplitude vibrations such as shake, which is exerted based on the resonance effect of the fluid flowing in the orifice passage 62, can be sufficiently achieved. Based on the resonance effect or hydraulic pressure absorption effect of the fluid flowing in the communication passage 64, the low dynamic spring effect against high frequency and small amplitude vibrations such as muffled sounds can be effectively exhibited. As a result, the formation of a direct acting spring due to the blockage of the orifice passage 62 when inputting vibrations in a high frequency range can be extremely effectively reduced or eliminated, providing excellent protection against input vibrations over a wide frequency range. It is possible to obtain vibration performance.

Moreover, in the engine mount in this example,
By disposing the movable block 56 in the first fluid chamber 58, the fluid is caused to flow in the communication passage 64 based on the resonance effect of the fluid in the vibration acting section formed in the second fluid chamber 58. Since a low dynamic spring can be achieved even during manual vibration in a higher frequency range, where the low dynamic spring effect due to fluid is not fully exerted, - it is better against input vibration over a wider frequency range. This also has the effect of realizing vibration-proofing performance.

Although the embodiments of the present invention have been described in detail above, these are literal illustrations, and the present invention is not to be construed as being limited only to these specific examples.

For example, the specific form of the orifice passage 62 is not similarly limited (it may also be formed on the inner cylinder fitting 10 side, etc.).

Further, the communication passage 64 can be formed not only on the inner circumferential surface of the outer cylindrical fitting 12 as illustrated, but also on the inner cylindrical fitting 10 side, inside the rubber elastic body 14, or the like.

Furthermore, as a flexible membrane that partitions the inside of the communication passage 64,
In addition to the rubber elastic membrane 50 shown in the example, a composite material in which a reinforcing material such as canvas is embedded inside the rubber elastic membrane, and various other flexible materials can be used, and the elasticity thereof is not necessarily required. do not have.

Furthermore, the movable prop 56 disposed within the fluid chamber 58 is not essential to the present invention.

Furthermore, in the engine mount according to the embodiment described above, when vibration is input between the inner and outer cylindrical fittings 10 and 12, the pair of fluid chambers 5 generate internal pressure fluctuations in which the increase and decrease are opposite to each other.
8.60, but it is also possible to form three or more such fluid chambers, or the
As shown in Japanese Patent No. 9349 and the like, one of the fluid chambers may be constituted by a variable volume equilibrium chamber at least partially defined by a flexible membrane.

In addition, in the above embodiment, an example was shown in which the present invention is applied to an automobile engine mount, but the present invention is also applicable to automobile differential mounts, member mounts,
Of course, the present invention can be advantageously applied to suspension bushings or vibration-proof coupling bodies in various devices other than automobiles.

In addition, although not listed, the present invention can be implemented in embodiments with various changes, modifications, improvements, etc. based on the knowledge of those skilled in the art, and such embodiments may be different from the present invention. It goes without saying that any of these are included within the scope of the present invention as long as they do not depart from the spirit of the invention.

(Effects of the Invention) As is clear from the above description, in the fluid-filled cylindrical mount device according to the present invention, when a low frequency large amplitude vibration is input, the flexible membrane disposed in the communication passage The deformation of the fluid is regulated by contact with the inner surface of the communication passage, and the flow of fluid through the communication passage between the fluid chambers is restricted, thereby effectively causing the flow of fluid through the orifice passage. As a result, a vibration damping effect based on the resonance effect of the fluid flowing through the orifice passage can be exerted. However, when high-frequency, small-amplitude vibrations that substantially block the orifice passage are input, the communication passage Based on the elastic deformation of the flexible membrane disposed therein, the fluid can be substantially allowed to flow between the fluid chambers through the communication passages, thereby causing resonance of the fluid flowing through the communication passages. Based on the action or hydraulic pressure absorption action, the mount can exhibit a low motion spring effect, thereby effectively reducing or eliminating the mount becoming a direct motion spring due to the blockage of the orifice passage. This means that excellent vibration damping performance can be exhibited against input vibrations over a wide frequency range.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing a specific example of an automobile engine mount to which the present invention is applied, FIG. 2 is a cross-sectional view taken along the line ■-■ in FIG. 1, and FIG. 4 is a side view in FIG. 2. Further, FIG. 5 is a cross-sectional view showing an integrally vulcanized molded product constituting the engine mount shown in FIG. 1, and FIG. 6 is a cross-sectional view taken along the line Vl--Vl in FIG. 5. Furthermore, FIG. 7 is a plan view showing the orifice metal fitting constituting the engine mount shown in FIG. 1. Moreover, FIG. 8 is a diagram showing a partition member constituting the engine mount shown in FIG. 1 taken out, and corresponds to the left side view in FIG. 9. 9 is a sectional view taken along line IX-IX in FIG. 8. FIG. Furthermore, FIG. 10 is an explanatory cross-sectional view showing an enlarged main part of the engine mount shown in FIG. 1. 0 4 6 0 4 0 4: Inner tube fitting: Rubber elastic body: Partition member: Rubber elastic membrane: Outer portion: Second fluid chamber: Communication passage 12: Outer tube fitting 38 Niorifice fitting 48: Mounting fitting 52: Inner portion 58: First fluid, chamber 62 niorifice passage

Claims (1)

[Claims] An inner cylindrical metal fitting and an outer cylindrical metal fitting arranged at a predetermined distance in the radial direction are connected by a rubber elastic body interposed between them, and the inner and outer cylindrical metal fittings are A fluid enclosure comprising a plurality of fluid chambers each filled with a predetermined incompressible fluid that causes a relative internal pressure change upon vibration input, and further provided with an orifice passage that communicates the fluid chambers with each other. In the type cylindrical mount device, a communication passage extending in the circumferential direction between the inner and outer cylindrical fittings, spanning between the fluid chambers, is formed independently of the orifice passage, and is located within the communication passage, A flexible membrane is provided that extends along the inner surface of the communicating passageway and partitions the communicating passageway into a substantially inner portion and an outer portion in the radial direction of the mount, and the inner portion and the outer portion are each filled with a different fluid. A fluid-filled cylindrical mount device, characterized in that the fluid-filled cylindrical mount device is configured to communicate with a chamber so that the internal pressure of the fluid chambers is applied to both sides of the flexible membrane.