JPH0384239A - Fluid sealed type mount device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] (Technical Field) The present invention relates to a fluid-filled mount device, which is particularly capable of controlling vibration damping characteristics such as a dynamic spring constant and a damping coefficient, and is suitable for use as an engine mount for automobiles, etc. The present invention relates to a fluid-filled mounting device that can be used as a fluid-filled mounting device.

(Background Art) Conventionally, vibration transmission systems have been interposed between members that constitute vibration transmission systems.
As a type of mount device that connects these members in a vibration-proof manner or supports one member in a vibration-proof manner with respect to the other member, a first support body and a second support body are arranged at a predetermined distance in the vibration input direction. A structure in which two supports are connected by a rubber elastic body interposed between them is known, and is suitably used as an engine mount for an automobile.

In addition, in recent years, in order to meet the demand for advanced vibration damping performance in automobiles, etc., in Japanese Patent Application Laid-Open No. 55-107142 and Japanese Patent Application Laid-open No. 57-9340, the above-mentioned supported by a second support,
A partition member extending in a direction substantially perpendicular to the vibration input direction is arranged, and at least a part of the pressure receiving chamber into which the vibration is input is placed on the first support body side with the partition member in between. A defined equilibrium chamber with a variable volume is formed on the opposite side of the pressure receiving chamber, a predetermined incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, and a predetermined incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber. Various so-called fluid-filled mounting devices have been proposed that have an orifice passage that communicates with each other.

By the way, when a plurality of different vibrations are input to such a mounting device, in addition to effectively isolating each vibration, different vibration isolation characteristics are required depending on the input vibration. be. For example, in the case of an engine mount that constitutes a support mechanism for an engine in a car, its anti-vibration characteristics include 15~
Low dynamic spring characteristics are required to improve vibration isolation for idling vibrations of about 3°0.
Regarding shake, a high dynamic spring or high damping characteristics are required in order to suppress the shaking of the engine unit and improve vibration damping performance.

However, in the conventional mounting device as described above, the vibration isolation characteristics are fixedly set based on the elasticity of the rubber elastic body, the form of the orifice passage, etc. It was extremely difficult to change the vibration isolation characteristics of the mount depending on the input vibration.
Therefore, it has not always been possible to fully satisfy the required vibration damping properties.

(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:
It is an object of the present invention to provide a fluid-filled mount device that is capable of controlling the switching of mount vibration isolation characteristics and that can obtain mount characteristics that can exhibit excellent vibration isolation effects depending on input vibration.

(Solution Means) In order to solve this problem, in the present invention, a first support body and a second support body, which are arranged at a predetermined distance in the vibration input direction, are arranged between the first support body and the second support body. The first support body and the second support body are connected by a rubber elastic body interposed therein, and a predetermined incompressible fluid is filled between the first support body and the second support body to prevent vibrations to be vibration-proofed. It forms an input pressure receiving chamber and a variable volume equilibrium chamber at least partially defined by a flexible membrane, and is provided with an orifice passage that communicates the pressure receiving chamber and the equilibrium chamber with each other. In the fluid-filled mounting device, a sealed air chamber of a predetermined volume is formed in which at least a portion of a wall portion exposed to the pressure receiving chamber and subjected to the liquid pressure is flexible, and the air chamber a pneumatic means for supplying and suctioning air to the air chamber; further supplying air to the air chamber by the pneumatic means;
Its feature is that it is provided with a switching means for switching and controlling the suction.

(Operation/Effect) That is, in the fluid-filled mount device having the structure according to the present invention, when the pressure in the air chamber is approximately atmospheric pressure, the flexibility forming the air chamber is reduced. By deforming the wall portion in accordance with changes in the fluid pressure within the pressure receiving chamber, changes in the fluid pressure within the pressure receiving chamber can be absorbed and reduced, thereby avoiding high dynamic springs due to the fluid pressure of the enclosed fluid. A low dynamic spring characteristic based on the elasticity of the rubber elastic body can be exhibited, and on the other hand, under a state where negative pressure is applied to the air chamber, the flexible wall part is attracted and the flexible wall part By preventing deformation in response to changes in fluid pressure within the pressure receiving chamber, fluctuations in fluid pressure within the pressure receiving chamber are effectively induced.
Since a fluid flow is also generated through the orifice passage, high dynamic spring characteristics and high damping characteristics can be advantageously exhibited based on the hydraulic pressure of the sealed fluid and the resonance effect of the fluid made to flow within the orifice passage. That's what happens.

Therefore, in such a fluid-filled mounting device, by controlling the supply and suction of air to the air chamber by the pneumatic means, the dynamic spring constant and damping coefficient can be changed as appropriate. It is possible to switch the mount vibration isolation performance according to the required vibration isolation characteristics, and thereby excellent vibration isolation performance can be advantageously exhibited under a wide range of conditions.

(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 and 2 show a specific example of an automobile engine mount having a structure according to the present invention. In this figure, reference numerals 10 and 12 indicate first and second support fittings as second and second supports, respectively, which are separated by a predetermined distance in the vibration input direction (vertical direction in FIG. 1). It is arranged as follows.

Specifically, the first support fitting 10 is formed into a substantially thick-walled cylindrical shape with a bottom, and has a central hole 14 extending in the axial direction provided therein. The opening axial end has a substantially annular plate shape,
A stopper rubber 15 protrudes at a predetermined height toward the axial side where the first support fitting 10 is located at its outer peripheral edge.
A stopper fitting 17 that is integrally provided is fixedly provided.

In addition, the second support fitting 12 has a stepped portion 1 at the center in the axial direction.
6 is provided and has a substantially stepped cylindrical shape consisting of a small diameter portion 18 and a large diameter portion 20, and the small diameter portion 18
A caulking portion 22 is provided at the side opening end, and a caulking portion 24 is provided at the opening end of the 20 large diameter portions.

These first support fittings 10 and second support fittings 1
2 refers to a state in which the closed end of the first support fitting 10 extends a predetermined amount into the second support fitting 12 from the large diameter portion 20 side, as shown in the figure. , are arranged concentrically with a predetermined distance apart in the axial direction, and in such a state, the first support metal fitting 10 and the second support metal fitting 12 are held together by the rubber elastic body 26. , are elastically connected and integrated.

Here, the rubber elastic body 26 is formed to have a substantially truncated conical shape as a whole, and the first support fitting 10 is embedded in the axial center from the small diameter side at the center in the radial direction. It is vulcanized and bonded to the outer circumferential surface of the second support fitting 10, and a substantially cylindrical mounting fitting 28 is disposed on the outer circumferential surface. It is vulcanized and bonded. in short,
The rubber elastic body 26 is formed as an integrally vulcanized product that is vulcanized and bonded to the first support fitting 10 and the mounting fitting 28.

Further, the rubber elastic body 26 includes a first support fitting 10.
At the portions facing each other in one radial direction with the mounting bracket 2
A pocket portion 30 is formed that opens onto the outer circumferential surface through a window portion 32 provided at 8 . Due to the pocket portions 30.30, the large diameter side portion of the rubber elastic body at the portion where these pocket portions are formed is thinned, and the flexible wall portion 42.4
It is said to be 2.

Furthermore, in these pocket parts 30, 30,
Communication holes 34 and 34 extending through the rubber elastic body 26 and the cylindrical wall portion of the first support fitting 10, which are formed in opposite directions, allow the inside of the center hole 14 of the first support fitting 10 to be The central hole 14 is connected to
A rotary valve 38 equipped with a connecting flow path 36 connecting the communication holes 34 and 34 is housed inside the pocket, and by rotating the rotary valve 38 with a rotary solenoid 40, the pocket Communication/blocking control is performed within the sections 30 and 30.

In addition, in the figure, 46 is a seal ring.

In such an integrally vulcanized molded product, the mounting fitting 28 is fitted into the large diameter portion 20 of the second support fitting 12, and both axial ends thereof are connected to the stepped portion 16 or the like. It is fixedly attached to the second support metal fitting 12 by being held between the tightening portion 24, and thereby, the first support metal fitting 10 is fixedly attached to the second support metal fitting 12 with the rubber elastic body 26. and the second support fitting 12 are integrally and elastically connected.

In addition, in such an integrally vulcanized molded product, the pocket portion 30.
The openings of the window portions 32.32 of the mounting bracket 28, which are the openings of 30, are respectively closed and sealed, so that the pocket portions 30.30 can communicate with each other through the communication holes 34.34, respectively. Note that a sealed air chamber 41 having a predetermined volume is formed.

Furthermore, in these air chambers 41, 41, the inside of one of the air chambers 4, 1 is connected to a negative pressure source 45 as a pneumatic means through a pneumatic pipe line 43,
According to the operation of a switching valve 47 as a switching means arranged on the pneumatic pipe line 43, the negative pressure source 45 and the atmosphere are selectively connected. Note that the negative pressure or atmospheric pressure exerted in one of the air chambers 41 is caused by the communication hole 3.
4.34, it is also applied to the inside of the other air chamber 41.

Further, a stopper member 49 having a substantially thick plate shape is accommodated in each of the air chambers 41 and 41, and is spaced apart from a predetermined gap with respect to the inner circumferential surface of the pocket portion 30 constituting the air chamber 41. It is disposed by being fixedly attached to the second support fitting 12 with bolts or the like (not shown). In addition, these stopper members 49, 49 are attached to the pocket portion 3 when the integrally vulcanized molded product is assembled to the second support fitting 12.
0.30 and is fixed to the second support fitting 12 with bolts or the like after such assembly,
It will be assembled.

Further, the material of the stopper member 30 is not particularly limited as long as it does not have high compressibility or flexibility; for example, metal, synthetic resin, rubber elastic body, etc.
Any of various materials can be suitably used.

On the other hand, a diaphragm 44 as a flexible film made of a thin rubber film is disposed in the opening on the small diameter portion 18 side of the second support fitting 12, and is vulcanized and bonded to the outer peripheral edge of the diaphragm 44. The outer peripheral edge of the ring metal fitting 4 is held between the caulking portions 22 of the second support metal fitting 12, so that the second support metal fitting 1 is held by the diaphragm 44.
The opening on the small diameter portion 18 side of No. 2 is closed.

The diaphragm 44 closes the opening on the small diameter portion 18 side of the second support fitting 12, thereby defining a sealed chamber inside the second support fitting 12. Further, on the outside of the diaphragm 44, a protective fitting 50 having a substantially shallow cylindrical shape is fixed at its outer peripheral edge together with the diaphragm 44 by the caulking portion 22 of the second support fitting 12. It is arranged by

Further, a predetermined incompressible fluid such as water, alkylene glycol, polyalkylene glycol, silicone oil, etc. is sealed in the sealed chamber.

In addition, the sealing of such an incompressible fluid into a sealed chamber is as follows:
For example, the attachment of the fitting 28 to the diaphragm 44 to the second support fitting 12 can be advantageously carried out in such a fluid.

Furthermore, inside the sealed chamber filled with this incompressible fluid,
The partition member 52, which has a generally bottomed cylindrical shape as a whole, is fixed by caulking the opening part of its cylinder wall together with the diaphragm 44 with the caulking part 22 of the second support fitting 12, so that the bottom wall of the partition member 52 is fixed. In this case, the sealed chamber is partitioned into a direction substantially perpendicular to the vibration input direction.

By means of this partition member 52, the sealed chamber is located on the rubber elastic body 26 side, and the pressure receiving chamber 54, where internal pressure fluctuations are caused when vibration is input, is located on the diaphragm 44 side.
It is divided into two fluid chambers, including an equilibrium chamber 56 whose volume is variable by elastic deformation of the diaphragm 44.

Further, the partition member 52 is constituted by first and second partition fittings 58 and 60, each having a substantially bottomed cylindrical shape and superimposed in the axial direction.
And between the overlapping surfaces of the second partition fittings 58 and 600,
An orifice passage 62 is formed within the cylindrical wall of the partition member 52 to communicate the pressure receiving chamber 54 and the equilibrium chamber 56 with each other, while an orifice passage 62 is formed within the bottom wall of the partition member 52 to connect both partition fittings. communicated with the pressure receiving chamber 54 and the equilibrium chamber 56 through a plurality of communication holes 64 provided in 58 and 60, respectively.
A housing space 66 is formed in which a thin disc-shaped movable plate 68 is housed and arranged to be movable by a predetermined distance.

As is well known, the flow inside the orifice passage 62 can be made by appropriately adjusting the flow path length, flow cross-sectional area, etc. of the orifice passage 62 and the accommodation space 66 (communication hole 64). Based on the resonance effect of fluid, 10~30H corresponding to engine shake etc.
The high damping effect on input vibration in the low frequency range of about z is
In addition, based on the flow of the fluid flowing in the communication hole 64 or the resonance effect, the 50-1
The low dynamic spring effect against input vibrations in a high frequency range of about 00H2 can be exerted.

Thus, in the engine mount having the above structure, the first support metal fitting 10 is attached to the engine unit side of the vehicle, while the second support metal fitting 12 is attached to the vehicle body frame side. As a result, it will be interposed between them.

In this mounted state, vibration is input between the first support metal fitting 10 and the second support metal fitting 12, but as shown in FIG. but,
When opened to the atmosphere through the air pressure pipe 43, they constitute one wall of the air chambers 41 and 41, and also constitute one wall of the pressure receiving chamber 54 when exposed to the pressure receiving chamber 54. The pressure receiving chamber 5
Since elastic deformation accompanying changes in the hydraulic pressure within the pressure receiving chamber 54 can be easily tolerated, fluctuations in the hydraulic pressure within the pressure receiving chamber 54 during vibration input are absorbed by the elastic deformation of the elastic walls 42 and 42. That will happen.

Therefore, under such conditions, fluid pressure fluctuations cannot be effectively generated within the pressure receiving chamber 54, and fluid flow through the orifice passage 62 cannot be effectively generated, so that the fluid pressure within the pressure receiving chamber 54 cannot be effectively generated. Alternatively, the movement spring rise due to the orifice effect can be avoided, and thereby the rubber elastic body 2
Therefore, the inherent low dynamic spring characteristics of 6 can be advantageously exhibited.

On the other hand, in such an engine mount, when the switching valve 47 is switched to connect the inside of the air chamber 41, 41 to the negative pressure source 45, as shown in FIG. The walls 42 , 42 are each attracted by the negative pressure in the air chamber 41 and brought into close contact with the stopper member 49 , thereby preventing their free deformation.

Therefore, under such conditions, fluid pressure fluctuations within the pressure receiving chamber 54 can be effectively generated upon vibration input, and fluid flow through the orifice passage 62 and the communication hole 64 based on the fluid pressure fluctuations is advantageous. As described above, there is a high damping effect on low frequency vibrations due to the resonance effect of the fluid flowing through the orifice passage 62, and a high damping effect on low frequency vibrations due to the flow or resonance effect of the fluid flowing through the communication hole 64. This means that the low dynamic spring effect against vibration can be effectively exhibited.

Therefore, in the engine mount as described above, by controlling the switching valve 47 according to the driving condition of the vehicle, it is possible to switch and control the vibration damping characteristics of the mount according to the input vibration. As a result, the ride comfort of the vehicle can be extremely advantageously improved. More specifically, for example, when the vehicle is stopped, the air chambers 41.41 are connected to the atmosphere, and when the vehicle is running, the air chambers 41.41 are connected to a negative pressure source. As a result, sufficient low dynamic spring characteristics can be exhibited against idling vibrations of about 15 to 30 Hz that are input when the vehicle is stopped, and excellent vibration isolation can be achieved. It exhibits high damping characteristics and can achieve excellent vibration damping performance against engine shake of about 10 to 30 Hz. This means that excellent anti-vibration performance can be achieved.

In particular, in the engine mount of this example,
Since the partition member 52 is provided with a hydraulic pressure absorption mechanism including a movable plate 68, the air chamber 41.
Even when the inside of 41 is connected to a negative pressure source, the low dynamic spring characteristic is effective against high-frequency vibrations such as muffled sounds that are input when the vehicle is running, based on the flow effect of the fluid flowing inside the communication hole 64. can be exhibited, and a sufficient vibration damping effect can be obtained.

Moreover, in the engine mount in this example,
By rotating the rotary valve 3 with the rotary solenoid 40, the communication hole 34 that communicates with the inside of the rain air chamber 41.41 can be shut off. The communication/blocking control of the air chambers 41 also has the advantage that the vibration damping characteristics in the direction perpendicular to the mount axis where the air chambers 4 and 41 are located facing each other can be changed as appropriate.

Although one embodiment of the present invention has been described in detail above, this is a literal illustration, and the present invention is not to be construed as being limited to such a specific example.

For example, although the engine mount in the above embodiment was equipped with a pair of air chambers 41, 41, the number is not limited, and one or three or more air chambers may be formed. It's okay.

Further, in the embodiment described above, the stopper member 49 was arranged in the air chamber 41 in a fixed state with respect to the second support metal fitting 12, but the stopper member 49 is not necessarily attached to the second support metal fitting 12. It does not need to be fixed and can be installed freely. Furthermore, such a stopper member 49 itself is not necessarily necessary in the present invention, and any structure that can prevent free deformation of the flexible wall portion 42 by the negative pressure exerted within the air chamber 41 may be used. For example, when a negative pressure is applied, the flexible wall portion may be brought into close contact with the inner surface of the air chamber located opposite to the flexible wall portion to prevent its free deformation.

Furthermore, in the embodiment described above, the air chamber 41 was formed within the rubber elastic body 26 and the flexible wall portion 42 was constituted by the rubber elastic body 26; , it is also possible to form it separately from the rubber elastic body 26,
For example, an annular metal fitting having a recess opening on the outer peripheral surface and at least a portion of the wall of the recess being flexible is fitted onto the inner peripheral surface of the second support metal fitting 12. By disposing it within the pressure receiving chamber 54, it is also possible to form an air chamber within such a recess.

Furthermore, the rotary valve 38 that controls communication/blocking between the air chambers 54 and 54 is not necessarily required.

Further, in the engine mount in the above embodiment, a hydraulic pressure absorption mechanism including a movable plate 68 was provided to the partition member 52, but such a hydraulic pressure absorption mechanism is not necessarily necessary. It's not something.

In addition, it goes without saying that the present invention can be advantageously applied not only to engine mounts for automobiles as illustrated, but also to differential mounts, body mounts, and vibration isolators other than automobiles.

In addition, although not listed, the present invention can be implemented in embodiments with various changes, modifications, improvements, etc. added based on the knowledge of those skilled in the art, and such embodiments are not limited to 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.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view showing a specific example of an automobile engine mount to which the present invention is applied, and FIG. 2 is a cross-sectional view of I[-[[ in FIG. 1. Moreover, FIG. 3 is a sectional view of a main part showing another operating state of the engine mount shown in FIG. 1. 0 26 2 4 7 4 2: First support fitting: Rubber elastic body: Flexible wall: Diaphragm: Switching valve: Pressure receiving chamber Niorifice passage 2 1 3 5 2 6: Second support fitting: Air chamber: Pneumatic pressure Pipe line: Negative pressure source: Partition member: Equilibrium chamber

Claims (1)

[Claims] A first support body and a second support body disposed at a predetermined distance in the vibration input direction are connected by a rubber elastic body interposed between them; A pressure receiving chamber filled with a predetermined incompressible fluid and into which vibrations to be damped are input is provided between the first support body and the second support body, and a pressure receiving chamber at least partially made of a flexible membrane. A fluid-filled mounting device comprising: a variable volume equilibrium chamber defined by a pressure receiving chamber; and an orifice passage communicating the pressure receiving chamber and the equilibrium chamber with each other; A sealed air chamber of a predetermined volume is formed in which at least a portion of the wall portion to which liquid pressure is applied is flexible, and a pneumatic means is provided for supplying and suctioning air to the air chamber; A fluid-filled mount device comprising a switching means for switching and controlling supply and suction of air to the air chamber by the pneumatic means.