JP7319933B2 - Fluid-filled anti-vibration device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid-filled vibration damping device used, for example, in an engine mount of an automobile, and more particularly to a fluid-filled vibration damping device provided with a movable member constituting a hydraulic pressure absorption mechanism.

Conventionally, a fluid filled type vibration damping device is known as a type of vibration damping device used for automobile engine mounts and the like. It is shown. The liquid-filled vibration isolator disclosed in Patent Document 1 includes a first liquid chamber and a second liquid chamber in which an incompressible fluid is sealed. flow, etc., and the desired anti-vibration effect is exhibited.

By the way, in the liquid-filled vibration isolator disclosed in Patent Document 1, a movable member such as an elastic partition film is arranged with respect to the partition member that partitions the first liquid chamber and the second liquid chamber. In Japanese Patent Laid-Open No. 2002-100000, the elastic partition membrane is applied with one of the liquid pressure of the first liquid chamber and the liquid pressure of the second liquid chamber on both sides, and the vibration input causes the pressure between the first liquid chamber and the second liquid chamber to move. It is displaced by internal pressure fluctuations relative to . By the displacement of the elastic partition membrane, the liquid pressure is transmitted so as to reduce the relative internal pressure difference between the first liquid chamber and the second liquid chamber. be done.

JP 2006-057675 A

However, in a fluid-filled vibration damping device having a movable member, when the movable member comes into contact with the partition member due to its displacement, there is a risk that a striking sound will be generated due to the collision. Therefore, in Patent Document 1, first and second ribs are provided on the inner peripheral portion of the elastic partition membrane, and the elastic partition membrane is displaced by being in contact with the partition members (orifice member and plate member) in advance at the ribs. However, it is also required to reduce the hammering sound by a structure different from that of Patent Document 1.

SUMMARY OF THE INVENTION An object of the present invention is to provide a fluid-filled anti-vibration device with a novel structure that can reduce striking noise caused by a movable member hitting a partition member with a simple structure.

Hereinafter, preferred embodiments for understanding the present invention will be described. can be recognized and employed as independently as possible, and can also be employed in combination with any of the components described in other aspects as appropriate. Accordingly, the present invention can be implemented in various alternatives without being limited to the embodiments described below.

A first aspect is a fluid-filled anti-vibration device comprising a main liquid chamber and a secondary liquid chamber in which an incompressible fluid is sealed, wherein a partition member that separates the main liquid chamber and the secondary liquid chamber is movable. A member is arranged, and the hydraulic pressure of the main liquid chamber and the sub-liquid chamber is exerted on both surfaces of the movable member, and the movable member is partially provided with a thin portion, and the partition member is provided with a contact portion facing the thin portion, and when the movable member and the partition member contact due to displacement of the movable member due to hydraulic pressure, the thin portion of the movable member contacts the partition member; The thin portion of the movable member, which first comes into contact with the contact portion, is annular and has a thickness greater than that of the thin portion. They are provided on the inner peripheral side and the outer peripheral side of the thin portion.

According to the fluid-filled vibration damping device constructed according to this aspect, when the movable member displaced by the action of the hydraulic pressure comes into contact with the partition member, the thin portion of the movable member first comes into contact with the partition member. , the partition member is provided with a contact portion facing the thin portion. As a result, the portion of the movable member that comes into first contact with the partition member is made thin and has a small mass, thereby suppressing the impact force exerted on the partition member by the impact of the movable member. Therefore, the hitting sound caused by the impact of the movable member against the partition member is reduced.

In addition, since the reduction of the hammering sound as described above is realized by providing the movable member with a partially thin-walled portion and providing the partition member with an abutting portion facing the thin-walled portion, the number of parts is increased. The hammering sound can be reduced by a simple structure without requiring a

In addition, according to the fluid-filled vibration damping device constructed according to this aspect, the thick portions are provided on the inner and outer peripheral sides of the thin portion, so that the deformation rigidity of the movable member is ensured by the thick portions. be done. Therefore, for example, when vibration is expected to absorb hydraulic pressure due to displacement of the movable member, excessive displacement of the movable member is prevented, and unnecessary contact of the movable member with the partition member is prevented. .

A second aspect is the fluid-filled vibration damping device according to the first aspect, wherein a portion of the partition member corresponding to the thick portion communicates with the main fluid chamber or the secondary fluid chamber. A communicating hole is formed.

According to the fluid-filled vibration damping device constructed according to this aspect, when the movable member is displaced by the action of hydraulic pressure, the thick portion is less likely to abut against the partition member, and the thin portion precedes the thick portion. It is easy to make contact with the contact portion of the partition member. In addition, the thick portion has greater deformation rigidity than the thin portion, and the communication hole can be effectively blocked by contacting the partition member so that the thick portion closes the communication hole.

A third aspect is the fluid-filled vibration damping device according to the first or second aspect, wherein the movable member is a movable membrane provided with a support portion supported by the partition member. .

According to the fluid-filled vibration damping device constructed according to this aspect, when hydraulic pressure acts on the movable film, partial displacement due to deformation of the movable film exerts hydraulic pressure transmission action. Moreover, since the movable film is provided with thin portions, the resonance frequency of the elastic deformation of the movable film can be tuned by adjusting the size, arrangement, and number of the thin portions. can be achieved in degrees.

A fourth aspect is the fluid-filled vibration damping device according to the first or second aspect, wherein the movable member is entirely displaceable in the plate thickness direction with respect to a housing area provided in the partition member. It is a movable plate accommodated in a state.

According to the fluid-filled vibration damping device constructed according to this aspect, in the movable plate, which tends to cause a problem of hammering noise due to displacement of the entire plate and coming into contact with the partition member, the thin-walled portion precedes the other portions of the partition member. By adopting a structure that abuts on the abutting portion of the , it is possible to effectively prevent the hammering sound.

A fifth aspect is the fluid-filled vibration damping device according to any one of the first to fourth aspects, wherein the contact portion has a convex shape protruding toward the thin portion. be.

According to the fluid-filled vibration damping device constructed according to this aspect, the abutting portion of the partition member has a convex shape and protrudes toward the thin-walled portion. It becomes easy for the contact portion of the partition member to contact the contact portion of the partition member first.

According to the present invention, with a simple structure, it is possible to reduce the hitting sound caused by the impact of the movable member against the partition member.

1 is a longitudinal sectional view showing an engine mount as a first embodiment of the invention; FIG. FIG. 2 is a perspective view of a partition member constituting the engine mount shown in FIG. 1; FIG. 3 is an exploded perspective view of the partition member shown in FIG. 2 The top view of the partition member shown in FIG. The bottom view of the partition member shown in FIG. The front view of the partition member shown in FIG. FIG. 5 is an enlarged cross-sectional view of the partition member shown in FIG. 4, corresponding to the VII-VII cross section of FIG. 4; FIG. 2 is an analysis diagram of deformation of the movable film in the engine mount shown in FIG. Each shows a state in which not only the thin portion but also the thick portion are in contact with the partition member. FIG. 2 is a vertical cross-sectional view showing an engine mount as a second embodiment of the present invention; FIG. 10 is an enlarged longitudinal sectional view showing a partition member constituting the engine mount shown in FIG. 9;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an automobile engine mount 10 as a first embodiment of a fluid-filled vibration damping device constructed according to the present invention. The engine mount 10 has a structure in which a first mounting member 12 and a second mounting member 14 are connected by a main rubber elastic body 16 . In the following description, the vertical direction basically refers to the vertical direction in FIG. 1, which is the direction of the center axis of the mount.

The first mounting member 12 has a mounting portion 18 having a substantially cylindrical shape. The mounting portion 18 has a screw hole 20 that opens in the upper surface and extends in the vertical direction. A flange-shaped portion 22 is integrally formed at the lower portion of the mounting portion 18 so as to protrude from the mounting portion 18 toward the outer periphery. Below the mounting portion 18 of the first mounting member 12, a fixing portion 24 having a tapered outer peripheral surface with a smaller diameter protrudes downward.

The second mounting member 14 has a tubular shape with a larger diameter than the first mounting member 12 . The second mounting member 14 of the present embodiment has a stepped cylindrical shape, and the diameter of the upper side is larger than that of the lower side with respect to the step of the intermediate portion.

The first mounting member 12 is arranged above the second mounting member 14 , and the first mounting member 12 and the second mounting member 14 are elastically connected to each other by the main rubber elastic body 16 . The main rubber elastic body 16 has a substantially truncated conical shape, and is vulcanization-bonded with the fixing portion 24 of the first mounting member 12 embedded in the upper end, which is the end on the small diameter side. , the second mounting member 14 is vulcanized and bonded to the lower end, which is the end on the large diameter side. The main rubber elastic body 16 is formed as an integrally vulcanized molded product including the first mounting member 12 and the second mounting member 14 .

The main rubber elastic body 16 has a recess 26 that opens to the end face on the large diameter side. The inner surface of the peripheral wall of the recess 26 has a tapered shape in which the diameter gradually decreases upward. By providing the recess 26, the elastic center axis connecting the cross-sectional centers of the left and right side portions of the longitudinal section of the main rubber elastic body 16 extending in the connecting direction of the first mounting member 12 and the second mounting member 14 is It extends in a direction of inclination downward toward the outer periphery.

The main rubber elastic body 16 is integrally formed with a tubular sealing rubber layer 28 extending downward from the peripheral edge of the opening of the recess 26 . The outer peripheral surface of the seal rubber layer 28 is fixed to the inner peripheral surface of the lower portion of the second mounting member 14 to cover the inner peripheral surface of the lower portion of the second mounting member 14 .

A flexible film 30 is attached to the second attachment member 14 fixed to the main rubber elastic body 16 . The flexible film 30 is a thin disc-shaped rubber film, and has a slack central portion that protrudes downward, and an annular fixing member 32 is fixed to the outer peripheral end. Then, the fixing member 32 is inserted into the inner periphery of the lower portion of the second mounting member 14 covered with the seal rubber layer 28, and the diameter of the second mounting member 14 is reduced. It is fitted to the second mounting member 14 via the seal rubber layer 28 . The space between the fixing member 32 and the second mounting member 14 is fluid-tightly sealed by the seal rubber layer 28 .

By attaching the fixing member 32 to the second mounting member 14 , the flexible film 30 is arranged to close the opening on the lower side of the second mounting member 14 . As a result, a fluid chamber 34 fluid-tightly separated from the external space is defined between the vertically facing surfaces of the main rubber elastic body 16 and the flexible film 30 .

The fluid chamber 34 contains an incompressible fluid. Although the type of incompressible fluid is not particularly limited, water, ethylene glycol, and the like are preferably used, for example. In order to efficiently obtain a vibration damping effect based on the flow action of the fluid, which will be described later, the incompressible fluid sealed in the fluid chamber 34 is desirably a low-viscosity fluid of 0.1 Pa·s or less.

A partition member 36 is arranged in the fluid chamber 34 . As shown in FIGS. 2 to 6, the partition member 36 has a substantially disk shape as a whole. As shown in FIG. 7, the partition member 36 is configured by combining a first member 38 and a second member 40 .

The first member 38 has a substantially disk shape. The first member 38 has a flange-shaped fixing piece 42 protruding from the upper end toward the outer periphery, and the fixing piece 42 is formed with bolt holes 44 penetrating in the vertical direction at a plurality of locations in the circumferential direction. . A first inner hole 46 as a communicating hole is formed in the radially central portion of the first member 38 so as to have a circular cross section and penetrate vertically. A first outer hole 48 as a communication hole extending in the circumferential direction is formed through the first member 38 in the vertical direction on the outer peripheral side of the first inner hole 46 .

An annular first inner peripheral portion 50 is formed on the inner peripheral side of the first outer hole 48 , and an annular first outer peripheral portion 52 is formed on the outer peripheral side of the first outer hole 48 . The portion 50 and the first outer peripheral portion 52 are connected by first connecting portions 54 at a plurality of locations in the circumferential direction. The first connecting portion 54 is provided across the upper side of the first outer hole 48 so as to partially cover the upper side of the first outer hole 48 in the circumferential direction. , the outer peripheral edge is integrally continuous with the first outer peripheral portion 52 . In this embodiment, as shown in FIG. 3, four first connecting portions 54, 54, 54, 54 are provided at equal intervals in the circumferential direction. can be changed.

As shown in FIG. 7, the second member 40 has a generally disk shape as a whole. The outer peripheral end portion of the second member 40 is a fixed portion 56 that protrudes upward and is thickened, and the second member 40 has a vertical cross-sectional shape that is recessed in the shape of a shallow cup. . A plurality of screw holes 58 are formed in the fixed portion 56 to open on the upper surface thereof. In addition, a circumferential groove 60 is formed in the fixing portion 56 so as to open in the outer peripheral surface and extend in the circumferential direction with a length of less than one turn. As shown in FIG. 3 , one end of the circumferential groove 60 is formed with a first communication port 62 that extends upward from the circumferential groove 60 and opens to the upper surface of the second member 40 . As shown in FIG. 4 , the other end of the circumferential groove 60 is formed with a second communication port 64 that extends downward from the circumferential groove 60 and opens to the lower surface of the second member 40 .

A second internal hole 66 as a communication hole is formed in the radially central portion of the second member 40 so as to have a circular cross section and penetrate vertically. A second outer hole 68 as a communication hole extending in the circumferential direction is formed through the second member 40 on the outer peripheral side of the second inner hole 66 in the vertical direction.

An annular second inner peripheral portion 70 is provided on the inner peripheral side of the second outer hole 68, and an annular second outer peripheral portion 72 is provided on the outer peripheral side of the second outer hole 68. The portion 70 and the second outer peripheral portion 72 are connected by second connecting portions 74 at a plurality of locations in the circumferential direction. The second connecting portion 74 is provided so as to partially cover the lower side of the second outer hole 68 in the circumferential direction, and the inner peripheral end thereof is integrally continuous with the second inner peripheral portion 70 . At the same time, the outer peripheral end portion is integrally continuous with the second outer peripheral portion 72 . In this embodiment, as shown in FIG. 4, four second connecting portions 74, 74, 74, 74 are provided at equal intervals in the circumferential direction. can be changed. The number and arrangement of the second connecting parts 74 may be different from the number and arrangement of the first connecting parts 54 .

The first member 38 and the second member 40 are, as shown in FIG. The inserted screws 76 are screwed into the screw holes 58 of the second member 40 to fix them together. As a result, the partition member 36 having a generally disc shape as a whole is constituted by the first member 38 and the second member 40 .

A housing area 78 is formed inside the partition member 36 . The accommodation area 78 is a space formed between the first member 38 and the second member 40 and extends from the first and second outer holes 48 and 68 to the outer peripheral side. As a result, the housing area 78 communicates with the first and second inner holes 46 and 66 and the first and second outer holes 48 and 68 .

A movable film 80 as a movable member is arranged in the accommodation area 78 of the partition member 36 . As shown in FIGS. 6 and 7, the movable film 80 has a substantially disc shape and is made of a rubber elastic material. The movable film 80 has an annular support portion 82 extending in the circumferential direction and having a substantially circular cross section at its outer peripheral end. The movable film 80 has an annular thin portion 84 , a first thick portion 86 located on the outer peripheral side of the thin portion 84 , and a second thick portion 86 located on the inner peripheral side of the thin portion 84 . A thick portion 88 is integrally provided.

The thin portion 84 is partially provided in the middle of the movable film 80 in the radial direction, and in this embodiment, has a ring shape that is continuous over the entire circumference in the circumferential direction. A radially central portion of the thin portion 84 is a flat plate portion 90 that spreads with a substantially constant thickness. Both ends of the thin portion 84 in the radial direction are formed as a thickness change portion 92 that gradually becomes thicker with distance from the flat portion 90 . The thickness changing portion 92 has inclined surfaces 94 that gradually incline both outwards in the vertical direction, which is the thickness direction, as the distance from the flat portion 90 increases in the radial direction.

Both the first thick portion 86 and the second thick portion 88 are larger in thickness dimension than the thin portion 84 and spread with a substantially constant thickness. The first thick portion 86 is provided between the support portion 82 and the thin portion 84 and has an annular shape that continues along the entire circumference in the circumferential direction. The first thick portion 86 is arranged at a position corresponding to the first and second outer holes 48 and 68 of the partition member 36, and has a radial width dimension equal to the width of the first and second outer holes 48 and 68. It is made larger than the dimensions. The second thick portion 88 is provided on the inner peripheral side of the thin portion 84 and has a substantially disk shape. The second thick portion 88 is arranged at positions corresponding to the first and second inner holes 46 and 66 of the partition member 36, and has an outer diameter dimension equal to the inner dimension of the first and second inner holes 46 and 66. are larger on both sides in the radial direction. The first thick portion 86 and the second thick portion 88 of the present embodiment have approximately the same thickness.

The movable membrane 80 is arranged between the first member 38 and the second member 40 and is housed in the housing area 78 . The movable film 80 is vertically sandwiched between the first member 38 and the second member 40 at the support portion 82 at the outer peripheral end, and is supported in a compressed state as necessary. A portion of the movable film 80 , which is outside the portion sandwiched by the first member 38 and the second member 40 toward the inner periphery, is vertically separated from at least one of the first member 38 and the second member 40 . In addition, the first thick portion 86 may be vertically sandwiched between the first member 38 and the second member 40 at the outer peripheral end connected to the support portion 82 .

A contact portion 96 is provided at a portion of the partition member 36 that faces the thin portion 84 of the movable film 80 . The contact portion 96 has a convex shape protruding toward the thin portion 84 from the inner surface of the wall in the vertical direction of the accommodation area 78 and is continuous over the entire circumference. The protruding tip surface of the contact portion 96 has a flat surface corresponding to the flat plate-shaped portion 90 of the thin portion 84 at the central portion in the radial direction of the partition member 36, and has thin portions at both ends in the radial direction of the partition member 36. The inclined surface 98 corresponds to the inclined surface 94 of 84 . The contact portion 96 faces the thin portion 84 of the movable film 80 with a predetermined gap. The distance between the contact portion 96 and the thin portion 84 in the vertical direction is smaller than the distance between the first and second thick portions 86 and 88 of the movable film 80 and the inner wall surface of the accommodating area 78 in the vertical direction. It is As described above, the contact portion 96 has a convex shape that protrudes from the inner wall surface of the housing area 78 , so that the contact portion 96 contacts the thin portion 84 that has a small vertical thickness and is concave on the surface of the movable film 80 . By bringing the portion 96 closer, the gap between the thin portion 84 and the partition member 36 can be set small.

In the present embodiment, the upper and lower inner surfaces of the accommodation area 78 of the partition member 36 facing both surfaces of the movable film 80 are substantially equal. The distance between the opposing surfaces between the thin portion 84 and the inner surface of the housing area 78 is smaller than the distance between the opposing surfaces between the thick portions 86 and 88 and the inner surface of the housing area 78 . Also, in the thickness change portion 92 between the thin portion 84 and the thick portions 86, 88, the distance between the facing surfaces with the housing area 78 gradually increases from the thin portion 84 toward the thick portions 86, 88. is changing.

The first and second inner holes 46 and 66 and the first and second outer holes 48 and 68 of the partition member 36 are opened to portions corresponding to the first and second thick portions 86 and 88 of the movable film 80. there is Accordingly, the first and second inner holes 46 and 66 and the first and second outer holes 48 and 68 are arranged at positions radially out of the thin portion 84 of the movable film 80 .

The partition member 36 with the movable film 80 disposed in the housing area 78 is inserted into the inner circumference of the lower portion of the second mounting member 14 and disposed between the main rubber elastic body 16 and the flexible film 30 in the vertical direction. be. The outer peripheral surface of the partition member 36 is pressed against the seal rubber layer 28 fixed to the inner peripheral surface of the second mounting member 14 by, for example, reducing the diameter of the second mounting member 14 . As a result, the space between the inner peripheral surface of the second mounting member 14 and the outer peripheral surface of the partition member 36 is fluid-tightly sealed by the seal rubber layer 28 .

By arranging the partition member 36 as described above, the fluid chamber 34 is vertically divided into two with the partition member 36 interposed therebetween. That is, above the partition member 36, a pressure receiving chamber 100 is provided as a main liquid chamber, the wall portion of which is partially formed by the main rubber elastic body 16. As shown in FIG. Below the partition member 36, an equilibrium chamber 102 is provided as a sub-liquid chamber, the wall portion of which is partly constituted by the flexible film 30. As shown in FIG.

By pressing the seal rubber layer 28 against the outer peripheral surface of the partition member 36 , the opening of the circumferential groove 60 extending from the outer peripheral edge of the partition member 36 is covered with the seal rubber layer 28 in a fluid-tight manner. A first communication port 62 and a second communication port 64 communicating with both ends of the circumferential groove 60 are open to the pressure receiving chamber 100 and the equilibrium chamber 102 . These constitute an orifice passage 104 that communicates the pressure receiving chamber 100 and the equilibrium chamber 102 with each other. Although the tuning frequency of the orifice passage 104 is not particularly limited, it is tuned to a low frequency corresponding to engine shake, for example.

The hydraulic pressure of the pressure receiving chamber 100 is applied to the upper surface of the movable film 80 through the first inner hole 46 and the first outer hole 48 . The hydraulic pressure of the equilibrium chamber 102 is applied to the lower surface of the movable membrane 80 through the second inner hole 66 and the second outer hole 68 . When a relative hydraulic pressure difference is generated between the pressure receiving chamber 100 and the equilibrium chamber 102 due to vibration input, the movable film 80 is displaced in the vertical direction by the action of the hydraulic pressure. Since the outer peripheral edge of the movable film 80 is fixedly supported by the partition member 36 , the displacement of the movable film 80 is partially caused by the elastic deformation of the movable film 80 .

In the engine mount 10 constructed as described above, the first mounting member 12 is mounted to a power unit (not shown), and the second mounting member 14 is mounted to a vehicle body (not shown). As a result, the power unit is attached to and supported by the vehicle body via the engine mount 10 .

Vibration in the vertical direction is input to the engine mount 10 when it is attached to the power unit and the vehicle body. When the input vibration is a low-frequency vibration in which the orifice passage 104 is tuned, fluid flow through the orifice passage 104 actively occurs between the pressure receiving chamber 100 and the balancing chamber 102 in a resonant state. As a result, the orifice passage 104 exerts a vibration damping effect based on the flow action of the fluid.

When a low-frequency, large-amplitude vibration such as an engine shake with the orifice passage 104 tuned is input, the movable film 80 cannot follow the amplitude of the input vibration and comes into contact with the inner surface of the vertical wall of the housing area 78 . As a result, the movable film 80 is substantially restrained by the inner wall surface of the housing area 78, and the hydraulic pressure transmission effect due to the displacement of the movable film 80 is not effectively exhibited. Therefore, the hydraulic pressure difference between the pressure receiving chamber 100 and the equilibrium chamber 102 is not reduced by the hydraulic pressure transmission of the movable film 80, and the fluid flow through the orifice passage 104 is efficiently generated.

When the movable film 80 abuts against the inner wall surface of the housing region 78 in the partition member 36 in the vertical direction, the thin portion 84 of the movable film 80 first abuts the partition member 36 as shown in FIG. That is, when a large-amplitude vibration is input in the vertical direction in the initial state shown in FIG. , the movable film 80 contacts the partition member 36 . At this time, as shown in FIG. 8(b), before the first and second thick portions 86 and 88 contact the inner wall surface of the housing area 78 of the partition member 36, the thin portion 84 is attached to the partition member. 36 is in contact with the contact portion 96 . More specifically, for example, after the flat portion 90 of the thin portion 84 abuts against the abutment portion 96, the thickness changing portion 92 of the thin portion 84 changes from the side closer to the flat portion 90 to the far side. It gradually comes into contact with the inclined surface 98 of the contact portion 96. As the amount of displacement of the movable film 80 further increases, the first and second thick portions 86 and 88 on both sides of the thin portion 84 come into contact with the partition member 36 as shown in FIG. 8(c). . As a result, the displacement of the movable film 80 is restricted by the partition member 36, and the hydraulic pressure transmission effect due to the displacement of the movable film 80 is prevented.

As shown in FIG. 8B, the thin portion 84 contacts the partition member 36 before the first and second thick portions 86 and 88, so that the portion of the movable film 80 outside the support portion 82 is partitioned. Impact is reduced when contacting the partition member 36 from a state separated from the member 36 . That is, when the movable film 80 is displaced and strikes against the partition member 36, the thin portion 84, which has a relatively small mass and low deformation rigidity as compared with the first and second thick portions 86, 88, By contacting the partition member 36 first, the impact at the time of contact is relatively small. As a result, the hammering sound caused by the contact of the movable film 80 with the partition member 36 is reduced.

Since the thin portion 84 is partially provided in the movable film 80, the initial contact area of the movable film 80 with respect to the partition member 36 is made relatively small. Therefore, the impact force at the time of contact is reduced as compared with the case where the movable film 80 contacts substantially simultaneously over a wide range. In this embodiment, the area of the thin portion 84 is made smaller than the sum of the areas of the first and second thick portions 86 and 88, so that the impact force when the thin portion 84 comes into contact with the partition member 36 is reduced. ing.

The thin portion 84 has a flat portion 90 and a thickness change portion 92, and the distance between the facing surfaces gradually increases from the thin portion 84 toward the thick portions 86 and 88. The flat plate portion 90 contacts the contact portion 96 while the plate portion 92 is separated from the contact portion 96 of the partition member 36, and thereafter the contact area of the thickness changing portion 92 with respect to the contact portion 96 gradually increases. Therefore, when the thin portion 84 abuts against the abutment portion 96, the impact force at the initial stage of abutment is further reduced, effectively preventing the hitting sound.

First and second thick portions 86 and 88 are provided on the outer peripheral side and the inner peripheral side of the thin portion 84 . Then, as shown in FIG. 8(c), the first and second thick portions 86 and 88 are formed at the opening peripheral portions of the first and second inner holes 46 and 66 and the first and second outer holes 48 and 68. It is pressed against the partition member 36 . As a result, the first and second inner holes 46, 66 and the first and second outer holes 48, 68 are effectively blocked by the first and second thick portions 86, 88 having relatively high deformation rigidity. , the transmission of hydraulic pressure through the first and second inner bores 46, 66 and the first and second outer bores 48, 68 is effectively prevented. In the movable membrane 80, if the blocking portion that blocks the first and second inner holes 46, 66 and the first and second outer holes 48, 68 has a small deformation rigidity, the first and second inner holes 46, This is because the transmission of hydraulic pressure through 66 and the first and second outer holes 48, 68 is allowed due to the deformation of the movable film 80 at the blocking portion.

If the input vibration is a small-amplitude vibration with a frequency higher than the tuning frequency of the orifice passage 104, the orifice passage 104 will be substantially clogged, and the vibration damping effect due to fluid flow will not be exhibited. On the other hand, the movable film 80 is slightly displaced in the thickness direction without being pressed against the partition member 36 . Therefore, hydraulic pressure is transmitted between the pressure receiving chamber 100 and the equilibrium chamber 102 due to the displacement of the movable film 80, and the clogging of the orifice passage 104 prevents the pressure receiving chamber 100 from being substantially sealed. The vibration damping effect is exhibited by the dynamic spring.

The movable film 80 is supported by the partition member 36 at the support portion 82 at the outer peripheral end portion, and the thin portion 84 and the first and second thick portions 86 and 88 inside the support portion 82 are both partition members. 36 is allowed to move vertically without being constrained. Therefore, the hydraulic pressure transmission action is efficiently exerted with respect to the amount of displacement of the movable film 80, and excellent anti-vibration performance can be obtained. The supporting portion supported by the partition member may be partially provided at the outer peripheral edge of the movable film in the circumferential direction, or may be provided in the shape of a projection in the center or middle of the movable film in the radial direction. good too.

FIG. 9 shows an automobile engine mount 110 as a second embodiment of a fluid-filled vibration damping device constructed according to the present invention. 10, the engine mount 110 has a structure in which a movable plate 112 as a movable member is arranged with respect to the housing area 78 of the partition member 36. As shown in FIG. In the following description, members and parts that are substantially the same as those in the first embodiment are denoted by the same reference numerals in the drawings, and descriptions thereof are omitted.

The movable plate 112 has a substantially disk shape, and includes a thin portion 84 , a first thick portion 86 provided on the outer peripheral side of the thin portion 84 , and a second thick portion 86 provided on the outer peripheral side of the thin portion 84 . 88 are integrally provided. The movable plate 112 is housed in the housing area 78 of the partition member 36 so as to be displaceable in the vertical direction, which is the plate thickness direction, without being constrained by the partition member 36 as a whole. In short, the maximum value of the vertical thickness of the movable plate 112 is set smaller than the distance between the inner wall surfaces of the housing area 78 in the vertical direction. is spaced apart in at least one of the vertical directions.

The distance between the thin portion 84 of the movable plate 112 and the abutting portion 96 of the partition member 36 in the vertical direction is the accommodation area 78 outside the first and second thick portions 88 and the abutting portion 96 of the movable plate 112 . It is smaller than the distance between the vertical direction facing the inner wall surface of the . Further, the outer diameter dimension of the movable plate 112 is smaller than the inner diameter dimension of the accommodation area 78 , and the outer peripheral surface of the movable plate 112 is not restrained by the partition member 36 .

The partition member 36 with the movable plate 112 disposed thereon is disposed between the pressure receiving chamber 100 and the equilibrium chamber 102 as shown in FIG. As a result, the movable plate 112 has the hydraulic pressure of the pressure receiving chamber 100 applied to its upper surface and the hydraulic pressure of the equilibrium chamber 102 applied to its lower surface. When a relative hydraulic pressure difference is generated between the pressure receiving chamber 100 and the equilibrium chamber 102 due to vibration input, the entire movable plate 112 is vertically displaced by the action of the hydraulic pressure.

In the engine mount 110 according to the present embodiment as well, when the orifice passage 104 receives tuned low-frequency, large-amplitude vibrations, the vertically displaced movable plate 112 contacts the partition member 36 at the thin portion 84 . Therefore, the impact caused by the movable plate 112 hitting the partition member 36 is reduced, and the hitting sound at the time of contact is suppressed.

Further, after the thin portion 84 abuts, the amount of displacement of the movable plate 112 is further increased, so that the first and second thick portions 86 and 88 are aligned with the opening peripheral portions of the first and second outer holes 68. The opening peripheral edge portions of the first and second inner holes 46 and 66 abut on the partition member 36 . As a result, at the openings of the first and second outer holes 48, 68 and the first and second inner holes 46, 66, the displacement of the movable plate 112 is prevented from exerting the pressure transmission action.

Thus, even if the movable member has a movable plate structure that allows the entire displacement within the housing area 78, the same effects as those of the first embodiment having the movable member of the movable film structure can be obtained. . The movable plate 112 of the present embodiment is entirely formed of a rubber elastic body and is allowed to undergo elastic deformation. Anti-vibration effect can also be expected based on the hydraulic pressure transmission effect due to the partial displacement associated with this.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited by the specific descriptions. For example, the thin portion is not limited to an annular shape that is continuous over the entire circumferential direction. Specifically, for example, it may have an arc shape partially provided in the circumferential direction, a linear shape extending in the radial direction, a curved shape, a circular shape, or the like. Alternatively, a plurality of thin portions may be intermittently provided in the circumferential direction so that the thin portions as a whole constitute an annular thin portion.

A plurality of thinned portions can also be provided in the movable member. For example, a plurality of annular thin portions having different diameters may be provided concentrically on the movable member, or thin portions of various shapes such as linear and circular may be provided at a plurality of spots on the movable member. good. In such a case, the partition member 36 may be provided with a contact portion at each corresponding portion.

Although the thin portion 84 of the above-described embodiment has the flat portion 90 with a constant thickness dimension, the thickness of the thin portion may partially change, for example. Moreover, in the above-described embodiment, the thick portions 86 and 88 have a substantially constant thickness as a whole, but the thick portions may have a varying thickness at least in part. The thickness change portion 92 that gradually increases the contact area with the partition member 36 between the thin portion 84 and the thick portions 86 and 88 is also not essential.

In the above-described embodiment, both surfaces of the movable members 80 and 112 are provided with the thin portions 84 that first come into contact with the partition member 36 when displaced by the action of fluid pressure, but they may be provided only on one surface. For example, in the case where there is a problem with the sound of the movable members 80 and 112 coming into contact with the partition member 36 in the load input direction in which the pressure in the pressure receiving chamber 100 is increased, the movable members 80 and 112 are displaced toward the auxiliary liquid chamber 102 side. Then, only the side contacting the movable members 80 and 112 may be provided with the thin portion 84 and the contacting portion 96 which contact the partitioning member 36 first when displaced by the action of the fluid pressure.

In the above-described embodiment, the partition member 36 is provided with the abutting portion 96 having a shape protruding toward the movable members 80 and 112 within the housing area 78, so that the distance between the facing surfaces of the thin portion 84 and the movable members 80 and 112 is reduced. is smaller than the distance between the facing surfaces of the thick portions 86, 88 and the movable members 80, 112, but such a configuration is not essential in the present invention. For example, even if the distance between the facing surfaces of the partition member 36 is set to be substantially the same between the thin portion 84 and the thick portions 86, 88, the amount of deformation caused by the pressure acting on the movable members 80, 112 will be By utilizing the fact that the thin portion 84 is larger than the thick portions 88 , the thin portion 84 can be brought into contact with the partition member 36 before the thick portions 86 and 88 . In the above-described embodiment, the centers of the thickness directions of the entire movable members 80 and 112 including the thin portion 84 and the thick portions 86 and 88 are set substantially on the same plane. , 88, the thin portion 84 is recessed from both upper and lower surfaces. The thin portion 84 and the thick portions 86 and 88 may be formed on the same plane on either the top or bottom surface of the member 80 or 112 .

By providing unevenness such as embossing on the thin-walled portion 84, it is possible to further reduce the impact force when contacting the partition member 36, thereby reducing the hammering sound. Similarly, the portions of the thick portions 86 and 88 that are expected to come into contact with the partition member 36 are provided with unevenness such as embossing to reduce the impact when the thick portions 86 and 88 come into contact with the partition member 36. You can also plan. Further, in addition to or instead of the unevenness of the thin portion 84 and the thick portions 86 and 88, textured unevenness or the like may be provided on the side of the partition member 36 that contacts. As can be seen from the above-described embodiment, the thick portions 86 and 88 are limited in displacement or deformation by their own elastic characteristics, so the contact area with the partition member 36 is the thin portion 84. It is often unnecessary compared to . For example, if the amount of displacement of the thick portions 86 and 88 due to the assumed input load can be limited by the contact of the thickness changing portion 92 with the partition member 36, the contact portion of the thick portions 86 and 88 can be positively moved by the partition member 36. There is no need to set it explicitly.

In the above embodiment, the first thick portion 86 and the second thick portion 88 have the same thickness, but the first thick portion 86 and the second thick portion 88 have different thickness dimensions, for example. may be Also, the relative size, position, shape, and specific thickness of the thin portion 84 and the thick portions 86 and 88 can be appropriately set according to the required anti-vibration properties. In the above-described embodiment, the supporting portion 82 is held at the outer peripheral edge of the movable film 80. However, the position of the supporting portion held therebetween is not limited. Additionally or alternatively, an annular support may be provided in the radially intermediate portion.

The movable member is not limited to a circular outer peripheral shape, and may have an oval, polygonal, irregular, or other outer peripheral shape. Also, the first mounting member, the second mounting member, the main rubber elastic body, the flexible film, the partition member, and the like are not limited to circular outer peripheral shapes.
In addition, the present invention originally includes each of the inventions described in (i) to (vi) below, and the configuration and effects thereof will be added.
The present invention
(i) A fluid-filled vibration damping device comprising a main liquid chamber and a secondary liquid chamber in which an incompressible fluid is sealed, wherein a movable member is arranged in a partition member that separates the main liquid chamber and the secondary liquid chamber. Hydraulic pressures of the main liquid chamber and the sub-liquid chamber are exerted on both surfaces of the movable member, and the movable member is partially provided with a thin portion, and the partition member is provided with the thin portion. When the movable member and the partition member are brought into contact with each other due to displacement of the movable member due to hydraulic pressure, the thin portion of the movable member contacts the corresponding contact portion of the partition member. Fluid-filled vibration isolator for first contact,
(ii) The thin portion of the movable member is annular, and thick portions having a thickness dimension larger than that of the thin portion are provided on the inner and outer peripheral sides of the thin portion of the movable member. The fluid-filled vibration isolator according to (i), provided with
(iii) The fluid-filled vibration damping device according to (ii), wherein a portion of the partition member corresponding to the thick portion is formed with a communication hole communicating with the main liquid chamber or the secondary liquid chamber. ,
(iv) The fluid-filled vibration isolator according to any one of (i) to (iii), wherein the movable member is a movable film having a support supported by the partition member;
(v) any one of (i) to (iii), wherein the movable member is a movable plate that is housed in a state in which the whole is displaceable in the plate thickness direction with respect to the housing area provided in the partition member; The fluid-filled vibration isolator according to the paragraph,
(vi) The fluid-filled vibration damping device according to any one of (i) to (v), wherein the contact portion has a convex shape protruding toward the thin portion;
including inventions related to
In the invention described in (i) above, when the movable member displaced by the action of the hydraulic pressure contacts the partition member, the thin portion of the movable member first contacts the partition member. Opposing abutments are provided. As a result, the portion of the movable member that comes into first contact with the partition member is made thin and has a small mass, thereby suppressing the impact force exerted on the partition member by the impact of the movable member. Therefore, the hitting sound caused by the impact of the movable member against the partition member is reduced. In addition, since the reduction of the hammering sound as described above is realized by providing the movable member with a partially thin-walled portion and providing the partition member with an abutting portion facing the thin-walled portion, the number of parts is increased. The hammering sound can be reduced by a simple structure without requiring a
In the invention described in (ii) above, the thick portions are provided on the inner peripheral side and the outer peripheral side of the thin portion, so that the deformation rigidity of the movable member is ensured by the thick portions. Therefore, for example, when vibration is expected to absorb hydraulic pressure due to displacement of the movable member, excessive displacement of the movable member is prevented, and unnecessary contact of the movable member with the partition member is prevented. .
In the invention described in (iii) above, when the movable member is displaced by the action of hydraulic pressure, it becomes difficult for the thick portion to contact the partition member, and the thin portion comes into contact with the partition member before the thick portion. easy to contact. In addition, the thick portion has greater deformation rigidity than the thin portion, and the communication hole can be effectively blocked by contacting the partition member so that the thick portion closes the communication hole.
In the invention described in (iv) above, when hydraulic pressure acts on the movable film, partial displacement due to deformation of the movable film exerts hydraulic pressure transmission action. Moreover, since the movable film is provided with thin portions, the resonance frequency of the elastic deformation of the movable film can be tuned by adjusting the size, arrangement, and number of the thin portions. can be achieved in degrees.
In the invention described in (v) above, in the movable plate, which tends to cause a problem of hammering noise because the entire plate is displaced and comes into contact with the partition member, the thin portion comes into contact with the contact portion of the partition member before the other portions. Striking sound can be effectively prevented by adopting the structure.
In the invention described in (vi) above, the abutting portion of the partition member has a convex shape and protrudes toward the thin-walled portion. It becomes easy to make contact with the contact part.

10 Engine mount (fluid-filled anti-vibration device)
12 First mounting member 14 Second mounting member 16 Main rubber elastic body 18 Mounting portion 20 Screw hole 22 Flange-shaped portion 24 Fixing portion 26 Recess 28 Seal rubber layer 30 Flexible film 32 Fixing member 34 Fluid chamber 36 Partition member 38 first member 40 second member 42 fixing piece 44 bolt hole 46 first inner hole 48 first outer hole 50 first inner peripheral portion 52 first outer peripheral portion 54 first connecting portion 56 fixing portion 58 screw hole 60 circumferential groove 62 First communication port 64 Second communication port 66 Second inner hole 68 Second outer hole 70 Second inner peripheral portion 72 Second outer peripheral portion 74 Second connecting portion 76 Screw 78 Housing area 80 Movable membrane (movable member)
82 Supporting portion 84 Thin portion 86 First thick portion 88 Second thick portion 90 Flat plate portion 92 Thickness changing portion 94 Inclined surface 96 Contact portion 98 Inclined surface 100 Pressure receiving chamber (main liquid chamber)
102 equilibrium chamber (secondary liquid chamber)
104 Orifice passage 110 Engine mount (fluid-filled anti-vibration device)
112 movable plate (movable member)

Claims (5)

A fluid-filled vibration isolator comprising a main fluid chamber and a secondary fluid chamber in which an incompressible fluid is sealed,
A movable member is disposed on a partition member that partitions the main liquid chamber and the secondary liquid chamber, and liquid pressures of the main liquid chamber and the secondary liquid chamber are applied to both surfaces of the movable member, and
The movable member is partially provided with a thin portion,
The partition member is provided with a contact portion facing the thin portion,
when the movable member and the partition member contact due to the displacement of the movable member due to hydraulic pressure, the thin portion of the movable member first contacts the corresponding contact portion of the partition member ;
The thin-walled portion of the movable member is annular, and thick-walled portions having a thickness larger than that of the thin-walled portion are provided on the inner and outer peripheral sides of the thin-walled portion of the movable member. Fluid- filled anti-vibration device. 2. A fluid filled type vibration damping device according to claim 1 , wherein a communicating hole communicating with said main liquid chamber or said secondary liquid chamber is formed in a portion of said partition member corresponding to said thick portion. 3. A fluid-filled vibration isolator according to claim 1, wherein said movable member is a movable film having a support supported by said partition member. 3. A fluid-filled vibration isolator according to claim 1, wherein said movable member is a movable plate that is housed in a state in which the entirety of said movable member can be displaced in a plate thickness direction with respect to a housing area provided in said partition member. . 5. The fluid filled type vibration damping device according to claim 1 , wherein the contact portion has a convex shape projecting toward the thin portion.

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