JPH0624593Y2 - Fluid-filled mounting device - Google Patents

Description

[Technical Field] The present invention relates to a fluid-filled mount device, and particularly to a damping effect for input vibration in a low frequency range and a vibration transmissibility reduction effect for input vibration in a middle to high frequency range. However, the present invention relates to a fluid-filled mount device that can be advantageously exhibited, and can be suitably used as an automobile engine mount or the like.

(Prior Art) Generally, in an engine mount for supporting an automobile engine unit in a vibration-proof manner, in order to prevent vibration due to a shake or bounce phenomenon, high damping performance against large-amplitude input vibration in a low frequency range and idling In addition, in order to prevent noise and vibration during traveling, low dynamic spring performance is required for small-amplitude input vibration in the middle to high frequency range.

So, in recent years, as a kind of such engine mount,
In Japanese Unexamined Patent Publication No. 57-9340, etc., first and second supports, which are arranged at a predetermined distance in the main vibration input direction, and the first and second supports are elastically connected. Inside the device equipped with a rubber elastic body, a partition wall extending in a direction substantially perpendicular to the vibration input direction is provided, and two fluid chambers (pressure receiving chambers) in which incompressible fluid is enclosed on both sides of the partition wall are provided. Chamber and the equilibrium chamber), and between the pressure receiving chamber and the equilibrium chamber, an orifice passage for communicating the two fluid chambers with each other and a predetermined amount of displacement in the direction of absorbing the fluid pressure difference between the two fluid chambers are possible. A so-called fluid-filled mount device having a structure in which the movable members are arranged is proposed.

That is, in the fluid-filled mount device having such a structure, when a large-amplitude vibration input in the low frequency range, the movable member is displacement-controlled and does not function, and fluid flow through the orifice passage occurs. A high damping effect can be exerted by the flow action of the fluid or the liquid column resonance action, and on the other hand, when the vibration of a small amplitude in the middle to high frequency range is input, the orifice passage is closed. The low dynamic spring characteristic can be exhibited by absorbing the increase in the hydraulic pressure in the pressure receiving chamber by the displacement of the movable member.

(Problem to be solved) However, in the mounting device having such a structure, the hydraulic pressure absorbing effect of the movable member in the pressure receiving chamber can be effectively exhibited only in a relatively narrow tuned frequency range. In the case of inputting vibration in a frequency range higher than the frequency range, it is practically impossible to function, causing a significant increase in the mount dynamic spring constant, resulting in a significant decrease in the vibration isolation effect. It was inherent.

(Solution Means) Here, the present invention has been made to solve the above problems, and is characterized in that the first vibration element is arranged opposite to the main vibration input direction at a predetermined distance. The support body and the second support body are elastically connected by a rubber elastic body interposed therebetween, and are substantially orthogonal to the main vibration input direction supported by the second support body. Across the partition metal fittings arranged in different directions, the pressure-receiving chamber into which the vibration to be isolated is input is located on the side of the first support, and at least a part of which is defined by a flexible membrane and has a variable volume. Equilibrium chambers are formed on the side of the second support respectively, and a predetermined incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, and between the pressure receiving chamber and the equilibrium chamber, both chambers are mutually connected. And the orifice passage that communicates with the chamber and a predetermined amount change in the direction to absorb the fluid pressure difference between both chambers. In the fluid-filled mount device, a movable member disposed so as to be movable is provided, and the rubber elastic body is formed in a hollow truncated cone shape having an opening on a large-diameter side end surface, and the small-diameter side thereof is While connecting the large diameter side to the second support body, the central portion of the partition fitting is projected into the pressure receiving chamber, and a through hole is provided around the projection portion. A rubber layer is attached to the side surface of the pressure receiving chamber of the partition fitting, and a stopper portion is formed on the tip end surface of the protrusion by the rubber layer, and the through hole is closed by the rubber layer to move the movable member. Further, the rubber layer is laterally projected at the outer peripheral edge portion of the partition fitting to form a groove extending circumferentially on the outer peripheral surface of the partition fitting, and the opening of the groove is defined by By covering with the second support, Lies in the formation of the.

Further, in the fluid-filled mount device having such a structure, a restricting member that restricts the amount of displacement of the rubber layer that closes the through hole is provided at at least one opening portion of the through hole. Is desirable.

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

First, FIG. 1 shows an example in which the present invention is applied to an automobile engine mount. In this figure, 10 and 12 are first and second support fittings, respectively, which are arranged facing each other at a predetermined distance in the main vibration input direction (vertical direction in the drawing). And the 1st support metal fitting 10 exhibits the substantially flat plate shape as a whole,
A frusto-conical projection 14 is formed in the central portion, and a plurality of mounting holes 16 are provided in the outer peripheral edge portion. Further, the second support fitting 12 is composed of a tubular fitting 18 having a substantially cylindrical shape and a bottom fitting 20 having a substantially bottomed cylindrical shape.
An opening peripheral edge portion of the bottom metal fitting 20 is formed by caulking and fixing to a peripheral edge portion of the tubular metal fitting 18 on one end side in the axial direction, and is attached to the bottom metal fitting 20 so as to protrude above the bottom surface. The bolt 22 is integrally provided.

Then, the first support metal fitting 10 and the second support metal fitting 1
As shown in the figure, 2 is a state in which the protrusion 14 of the first support fitting 10 and the opening side surface of the second support fitting 12 face each other and are positioned so as to face each other with a predetermined distance therebetween. In addition, in such a state, the first support fitting 10 and the second support fitting 12 are elastically connected by the rubber elastic body 24 to be integrated.

It should be noted that such an engine mount is mounted on either the vehicle body side or the power unit side including the engine in the mounting hole 16 of the first support fitting 10 and the mounting bolt 22 of the second support fitting 12, respectively. It will be attached, and by doing so, the power unit will be supported in a vibration-proof manner with respect to the vehicle body.

Here, the rubber elastic body 24 has a substantially hollow truncated cone shape having an inner hole 26 opened on the end surface on the large diameter side, and at the end surface on the small diameter side, the first supporting metal fitting 10 is formed. On the other hand, and at the large-diameter side peripheral portion thereof, the tubular metal fitting 18 constituting the second support metal fitting 12 is formed.
On the other hand, each of them is formed as an integrally vulcanized molded product which is vulcanized and adhered. The rubber elastic body 2
4, in the axial intermediate portion of the peripheral wall portion,
A thin taper tubular restraint fitting 27 is integrally embedded so that the peripheral wall portion of the rubber elastic body 24 can be prevented from being excessively bulged radially outward.

Further, a diaphragm 28 as a flexible film is arranged on the second support fitting 12 in a state where its outer peripheral edge is fluid-tightly sandwiched between the crimped portions of the tubular fitting 18 and the bottom fitting 20. As a result, a closed space including the inner hole 26 of the rubber elastic body 24 is formed on the diaphragm 28 on the first support fitting 10 side. A space 30 that allows the deformation of the diaphragm 28 is formed on the bottom metal fitting 20 side of the diaphragm 28.

In addition, a predetermined incompressible fluid such as water, polyalkylene glycol, silicone oil, etc. is enclosed in this closed space.

In addition, a partition member 32 having a substantially disk shape as a whole is superposed on the diaphragm 28 on the side of the first support fitting 10 in the closed space, and together with the diaphragm 28, the second support fitting 12 is provided. Metal fittings 1
8 and the bottom metal fitting 20 are arranged so as to partition the inside of the closed space in a direction perpendicular to the vibration input direction by sandwiching the peripheral portion thereof. However, the rubber elastic body 24 (the first support metal 1
0) side pressure receiving chamber 34 into which vibration to be isolated is input,
It is divided into two fluid chambers, a balance chamber 36 on the side of the diaphragm 28 (second support fitting 12) whose volume is variable by elastic deformation of the diaphragm 28.

Here, the partition member 32 covers the substantially disk-shaped partition fitting 40, which is caulked and fixed to the second support fitting 12 at the outer peripheral edge, and the surface of the partition fitting 40 on the pressure receiving chamber 34 side. In this way, the equilibrium chamber 3 of the partition metal fitting 40 and the rubber layer 42 integrally provided under the adhered state with a predetermined thickness
It is constituted by a displacement regulating metal fitting 44 having a substantially thin disk shape and assembled so as to be located on the 6th side.

More specifically, the partition fitting 40 has a substantially disc shape as shown in FIG. 2, and has a bottomed cylindrical shape that is formed so as to project in one axial direction at the center thereof. On the other hand, the outer peripheral edge portion is provided with the projecting portion 38, and on the outer peripheral edge portion, a cylindrical peripheral wall portion 46 bent and formed in the other axial direction, and the cylindrical peripheral wall portion 46.
And a holding portion 48 having an outer flange shape that is formed to be bent outward in the radial direction from the peripheral edge portion on the protruding end side. Further, a plurality of through holes 50 are provided around the protruding portion 38 in the circumferential direction. They are formed side by side.

Further, as shown in FIG. 3, the thin rubber layer 42 is adhered to the projecting side surface of the projecting portion 38 of the partition fitting 40 over substantially the entire surface thereof.
The rubber layer 42 constitutes a closing portion 52 for closing the opening of the through hole 50 of the partition fitting 40, and the rubber layer 42 is thickened on the protruding portion 38. The stopper portion 54 that is urged to project outward in the axial direction
Are formed. Furthermore, the rubber layer 42 has an annular projection 56 formed on the outer peripheral edge thereof so as to project radially outward from the partition fitting 40, whereby the tubular peripheral wall portion 46 of the partition fitting 40 is formed. Also, in cooperation with the sandwiching portion 48, a circumferential groove 58 is formed which is open outward in the radial direction and extends in the circumferential direction by a length of a little less than one round.

Furthermore, in the partition fitting 40, the displacement restricting fitting 44 having a substantially annular plate shape is positioned in a state of abutting on the surface opposite to the side on which the rubber layer 42 is adhered. , The cylindrical fitting portion 62 provided in the central portion,
The partition fitting 40 is fixedly assembled by being fitted into the protruding portion 38 of the partition fitting 40. Then, as shown in FIG. 3, the displacement restricting metal fitting 44 has a predetermined width in a radial direction at a portion located at the opening of each through hole 50 when assembled to the partition metal fitting 40. The extending restricting pieces 64 are radially provided as a whole, and the displacement amount of the closing portion 52 to the inside of the through hole 50 can be restricted by contact with the restricting pieces 64. In addition,
The displacement restricting metal fitting 44 does not close the opening of the through hole 50 in the partition metal fitting 40, and as is clear from FIG. 3, the through hole 50 includes the restricting pieces 64, 6 respectively.
It is opened through a window portion 66 provided between the four.

The partition member 32 is assembled by caulking and fixing the partition member 32 together with the diaphragm 28 to the second support fitting 12 in the holding portion 48 of the partition fitting 40. The stopper portion 54 is projected into the pressure receiving chamber 34, and the projecting end surface is positioned to face the inner surface of the pressure receiving chamber 34 at a predetermined distance in the main vibration input direction.
The peripheral groove 58 serves as a stopper mechanism when an excessive vibration load is input to the mount device.
By closing the opening of the cylinder fitting 18 with the tubular metal fitting 18, both ends are communicated with the pressure receiving chamber 34 and the equilibrium chamber 36 through the communication holes 68, 70, respectively, so that the chambers 34, 36 can communicate with each other. A movable member capable of absorbing a change in hydraulic pressure in the pressure receiving chamber 34 based on the displacement of the pressure receiving chamber 34 and the equilibrium chamber 36 in the opposing direction by the closing portion 52. That is, the (hydraulic pressure absorption mechanism) is configured.

Thus, in such an engine mount, when the vibration is input, the internal pressure fluctuation is caused in the pressure receiving chamber 34 based on the elastic deformation of the rubber elastic body 24, while the equilibrium chamber 36 is generated. In the inside, since the volume change is allowed by the deformation of the diaphragm 28, the internal pressure fluctuation can be substantially avoided, and therefore, based on the internal pressure difference between the pressure receiving chamber 34 and the equilibrium chamber 36, Orifice passage 7
2 causes a flow of the fluid through the displacement of the closing portion 52 as a movable member, and as is well known, the flow resistance of the fluid flowing through the orifice passage 72 or the vibration damping due to the liquid column resonance is generated. The characteristic and the low dynamic spring characteristic due to the absorption of the hydraulic pressure in the pressure receiving chamber 34 due to the displacement of the closing portion 52 can be exhibited at the time of the vibration input in the tuned frequency range.

In the present embodiment, the orifice passage 72
For the input vibration in the low frequency range corresponding to the generation frequency of engine shake or bounce, specifically, the frequency range around 10 Hz,
The through hole 50 in the hydraulic pressure absorbing mechanism including the closing portion 52 is set so that excellent damping ability can be exhibited.
Area, the elastic modulus of the closed portion 52, etc., are in the mid-frequency range where vibration isolation is required for the mount, specifically 150 to 2
It is set so that a low dynamic spring can be achieved with respect to input vibration in a predetermined frequency range within a range of about 00 Hz, and the displacement amount of the closing portion 52 is abutted against the displacement regulating metal fitting 44. When a low-frequency, large-amplitude vibration is input, which is regulated to a predetermined amount and requires the vibration damping capability of the orifice passage 72, it is set so that it does not substantially function as a hydraulic pressure absorption mechanism. The vibration damping ability of the orifice passage 72 with respect to the input vibration of (1) can be secured.

By the way, here, the hydraulic pressure absorbing mechanism including the closing portion 52 cannot substantially function at the time of inputting vibration in a frequency range higher than the set frequency, and therefore the mount dynamic spring constant is remarkable. In the engine mount according to the present embodiment, which is provided with the rubber elastic body 24 having the hollow truncated cone shape as described above, the pressure receiving by the rubber elastic body 24 is caused. Room 3
By positively utilizing the transverse wave surging phenomenon caused in the wall portion of No. 4, it is possible to avoid such an increase in the mount dynamic spring constant.

More specifically, in such an engine mount,
The wall portion of the pressure receiving chamber 34 constituted by the rubber elastic body 24 can be considered as an elastic body whose both ends are constrained by the first support fitting 10 and the second support fitting 12.
Therefore, when the vibration is input, the pressure receiving chamber 34
A transverse wave surging phenomenon, which is a kind of resonance phenomenon, is caused in a predetermined frequency range on the basis of the fluctuation of the internal pressure of the. When the surging phenomenon occurs, when the vibration is input, the rubber elastic body 24 forming the wall portion of the pressure receiving chamber 34 is kept in contact with the pressure receiving chamber 34.
Since it is deformed in a direction to eliminate the internal pressure inside, the reduction of the mount dynamic spring constant, and hence the vibration transmissibility, can be effectively achieved.

By the way, the frequency f at which such a surging phenomenon occurs is set according to the following equation.

l: Free length of the rubber elastic body 24 forming the wall of the pressure receiving chamber 34 G: Transverse elastic modulus (dynamic shear modulus) of the rubber elastic body 24 forming the wall of the pressure receiving chamber 34 ρ: Rubber elastic body 24 In this case, particularly in the engine mount having the above-described structure, the stopper that restricts the excessive deformation of the rubber elastic body 24 when a large vibration load is input is formed on the partition fitting 40 by projection. The pressure receiving chamber (34), which is generally used in the past, is constituted by the stopper portion 54 that is positioned inside the pressure receiving chamber 34.
Of the first support metal fitting 10 and the second support metal fitting (12) in comparison with a structure in which a stopper portion is provided on the opposing surface of the first support metal fitting (10) and the second support metal fitting (12). The separation distance in the vibration input direction from the second support fitting 12 can be set to be large, whereby the pressure receiving chamber 3
The free length l of the rubber elastic body 24 forming the wall portion 4 can be advantageously increased.

Therefore, in the engine mount having the above-described structure, the rubber elastic body 24 is not changed in its material surface, in other words, the durability and load bearing performance of the rubber elastic body 24 are sufficiently secured. At the same time, the free length l of the rubber elastic body 24 forming the wall portion of the pressure receiving chamber 34 can be set to a large value, so that the frequency at which the transverse wave surging phenomenon is generated can be lowered, and the surging generation frequency can be mounted. Against the frequency range that requires anti-vibration performance, specifically 150
It is possible to lower the frequency to about 500 Hz, and to set it in the frequency range of 200 Hz or higher in an advantageous manner.

Then, at the time of vibration input in a frequency range higher than the frequency set in the hydraulic pressure absorbing mechanism, the hydraulic pressure absorbing mechanism including the closing portion 52 cannot substantially function,
The rise of the internal pressure in the pressure receiving chamber 34 can be effectively reduced by the surging phenomenon in the wall portion of the rubber elastic body 24, and thus, the mount dynamic spring constant of the vibration input in such a high frequency range can be reduced. The reduction can be effectively achieved.

In such an engine mount, by increasing the free length l of the wall of the pressure receiving chamber 34, the shearing component exerted on the rubber elastic body 24 at the time of inputting a load is increased. In particular, in the present embodiment, the restraint metal fitting 27 arranged in the middle portion of the wall portion of the pressure receiving chamber 34 increases the compression component exerted on the rubber elastic body 24 at the time of vibration input, so that the rubber elastic body is increased. Therefore, the deterioration of the durability of No. 24 can be suppressed.

In addition, in such an engine mount, since the closing portion 52 and the stopper portion 54 forming the hydraulic pressure absorbing mechanism are integrally formed by the rubber layer 42, the manufacturing is easy and the manufacturing cost is low. It also has the advantage of low.

Moreover, in such an engine mount, the stopper portion 54 is formed on the tip end surface of the protruding portion 38 of the partition fitting 40 and is substantially independent of the closing portion 52. Even if the stopper portion 54 is deformed or cracked due to the contact with the supporting metal fitting 10 side, the closing portion 52 is hardly affected, and the desired hydraulic pressure absorption effect of the closing portion 52 is effectively obtained. And it can be demonstrated stably.

Further, in the engine mount according to the present embodiment, since the displacement restricting metal fitting 44 that restricts the displacement of the closing portion 52 that is the movable member is provided, the displacement of the orifice passage 72 at the time of vibration input of low frequency and large amplitude is provided. The vibration damping effect based on the flow of fluid is stable,
It can be effectively exerted.

Furthermore, in this embodiment, since the annular projection 56 formed of the rubber layer 42 constitutes the wall portion of the orifice passage 72, the number of parts is reduced. The manufacturing can be facilitated more advantageously.

Although the embodiments of the present invention have been described in detail above, this is a literal example, and the present invention should not be construed as being limited to such specific examples.

For example, as the rubber elastic body 24, one having an inner hole 26 formed so as to penetrate therethrough in the axial direction is used, and the small-diameter side end face opening is closed by the first support fitting 10. It is also possible.

In addition, the flow passage cross-sectional area and length of the orifice passage are appropriately changed, and for example, the orifice passage may be formed to have a length of two or more in the circumferential direction on the outer peripheral portion of the partition member.

Further, the specific structure of the displacement restricting metal fitting 44 that restricts the displacement of the closed portion 52 as the movable member is not limited in any way, and may be arranged on the pressure receiving chamber 34 side.

Further, instead of such a displacement regulating member, the closing portion 52
The same effect can be obtained by disposing a displacement regulating material such as canvas in the inside.

Although not listed one by one, the present invention can be implemented in variously modified, modified, improved, etc. modes based on the knowledge of those skilled in the art. It goes without saying that all of them are included in the scope of the present invention without departing from the spirit.

(Effect of the Invention) As is apparent from the above description, according to the present invention as described above, it is possible to advantageously secure the free length of the rubber elastic body in the portion forming the wall portion of the pressure receiving chamber. Therefore, based on the surging phenomenon in such a wall portion, it is possible to effectively avoid a significant increase in the internal pressure in the pressure receiving chamber at the time of vibration input in the high frequency range in which the movable member cannot substantially function, and thereby the high frequency A reduction in the vibration transmissibility at the time of vibration input in the region can be achieved.

Further, in the mounting device according to the present invention, the stopper, the movable member and the orifice passage forming groove are formed integrally with the partition fitting by applying the rubber layer to the partition fitting. The reduction and the consequent ease of manufacture can be achieved very advantageously.

Moreover, in such a mounting device, since the orifice passage is formed so as to extend in the circumferential direction on the outer peripheral surface of the partition fitting, the length of the orifice passage can be advantageously secured, and an excellent vibration damping effect is exhibited. To get.

Further, in such a mounting device, since the stopper portion is formed on the tip end surface of the protruding portion of the partition fitting and is substantially independent from the formation portion of the movable member, the stopper portion is not deformed or cracked. Even if the occurrence of the above occurs, there is almost no effect on the formation site of the movable member, and the desired hydraulic pressure absorption effect of the movable member can be effectively and stably exhibited.

Furthermore, by arranging the regulating member for regulating the displacement of the rubber layer which is the movable member, the desired vibration damping effect by the rubber layer and the orifice passage can be effectively and stably exhibited.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional explanatory view showing an example in which the present invention is applied to an engine mount of an automobile, FIG. 2 is a perspective view showing a partition fitting constituting such an engine mount, and FIG. It is a perspective view which shows the partition member comprised including such a partition metal fitting. 10: 1st support metal fitting, 12: 2nd support metal fitting 24: Rubber elastic body, 26: Inner hole 28: Diaphragm, 32: Partition member 34: Pressure receiving chamber, 36: Equilibrium chamber 40: Partition metal fitting, 42: Rubber Layer 44: Displacement regulating metal fitting, 50: Through hole 52: Closure portion, 54: Stopper portion 56: Annular protrusion portion, 58: Circumferential groove 72: Orifice passage

Claims (2)

[Scope of utility model registration request] 1. A first support body and a second support body, which are opposed to each other at a predetermined distance in a main vibration input direction, are elastically connected by a rubber elastic body interposed therebetween. In addition, the pressure receiving chamber to which the vibration to be isolated is inputted is sandwiched by the partition metal fittings supported by the second support and arranged in a direction substantially perpendicular to the main vibration input direction. A variable volume equilibrium chamber, at least a part of which is defined by a flexible membrane, is formed on the support side, and is formed on the second support side, and a predetermined incompressible fluid is formed in the pressure receiving chamber and the equilibrium chamber. While enclosing the pressure receiving chamber and the equilibrium chamber, an orifice passage that allows the two chambers to communicate with each other, and a movable member that is displaceable by a predetermined amount in the direction that absorbs the fluid pressure difference between the two chambers. To
In the fluid-filled mount device provided, the rubber elastic body is formed in a hollow truncated cone shape having an opening on a large-diameter side end face, and the small-diameter side is the first support and the large-diameter side is the A rubber layer is formed on the side surface of the pressure-receiving chamber of the partition fitting while connecting the second support with the central portion of the partition fitting protruding into the pressure-receiving chamber and providing a through hole around the protruding portion. To form a movable member by closing the through hole with the rubber layer while forming a stopper portion on the tip surface of the protruding portion with the rubber layer. By projecting laterally at the outer peripheral edge of such a partition fitting to form a groove extending in the circumferential direction on the outer peripheral surface of the partition fitting, and covering the opening of the groove with the second support, A flow characterized in that the orifice passage is formed. Body-mounting mount device. 2. The fluid-filled mount according to claim 1, wherein a regulating member is disposed at at least one opening portion of the through hole to regulate a displacement amount of the rubber layer closing the through hole. apparatus.