JP2002303349A - Vibration control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deterioration of vibration control efficiency caused by leakage of liquid from an outer peripheral groove formed on an intermediate block without disposing a seal member between the intermediate block and an outer cylinder. SOLUTION: In a condition that an outer peripheral surface 24C of the intermediate block 24 is pressed against an inner peripheral surface of the outer cylinder 16, protruding parts 82 and 84 extending along a groove end of the outer peripheral groove 46 at an axial direction center side are pressed onto the inner peripheral surface of the outer cylinder 16 in order to prevent a clearance. Thus, the liquid in the outer peripheral groove 46 is prevented from leaking to the axial direction center side through a space between the outer peripheral surface 24C of the intermediate block 24 and the inner peripheral surface of the outer cylinder 16. A flange part 22A of an intermediate cylinder 22 is pressed against the inner peripheral surface of the outer cylinder 16 though a sealing part 86 at an axial direction outside of the outer peripheral groove 46. Thus, the liquid in the outer peripheral groove 46 does not flow out along the axial direction outer than the flange part 22A of the intermediate cylinder 22 even when the liquid is leaked out to outside of the axial direction through the space between the outer peripheral surface 24C of the intermediate block 24 and the inner peripheral surface of the outer cylinder 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration isolator for preventing transmission of vibration from a member that generates vibration, and is applicable to, for example, a case where transmission of vibration from an engine mounted on a vehicle is prevented. Things.

[0002]

2. Description of the Related Art For example, an anti-vibration device as an engine mount is disposed between an engine of a vehicle serving as a vibration generating portion and a vehicle body serving as a vibration receiving portion. There is known a structure that absorbs vibration and prevents vibration from being transmitted to the vehicle body. That is, as an example of this vibration isolator, an inner cylinder is disposed on the inner peripheral side of an outer cylinder formed in a cylindrical shape, and an elastic body is stretched between these inner cylinders and the outer cylinder. There is a so-called bush type having a structure in which a main liquid chamber and a sub liquid chamber are provided inside a liquid passage, and these liquid chambers are connected to each other by a restriction passage serving as an orifice.

[0003] When vibrations occur due to the operation of the mounted engine, the vibrations are absorbed by the internal resistance of the elastic body, and the liquid in the restriction passage connecting the main liquid chamber and the sub liquid chamber is communicated. As a low dynamic spring due to liquid column resonance or the like, vibration is absorbed or vibration is attenuated, and transmission of vibration is prevented.

[0004] On the other hand, the engine speed varies widely with changes in vehicle conditions, and the vibration frequency becomes wide with a wide operating state of the engine. Therefore, in order to maintain the vibration isolation characteristics even in such vibrations of a wide range of frequencies, a vibration isolation device having a plurality of orifices which are restriction passages having different lengths and inner diameters has been proposed in recent years. Became. Here, in order to effectively attenuate low-frequency vibrations such as shake vibrations, it is necessary to make the length of the restriction passage corresponding to the low-frequency vibrations sufficiently long.

As a bush type vibration damping device,
For example, an inner cylinder connected to one of the vibration generator and the vibration receiver, an outer cylinder connected to the other of the vibration generator and the vibration receiver, and a rubber elastic body fixed to the outer peripheral surface of the inner cylinder And an intermediate cylinder in which the outer peripheral portion of the elastic body is fixed to the outer peripheral side of the inner cylinder and flange portions are provided at both ends in the axial direction, and the pair of flange portions are inserted into the outer cylinder. A concave cavity formed in an elastic body facing an opening formed between a pair of flanges in the intermediate cylinder, and an opening formed by pressing against an inner peripheral surface of the outer cylinder and a peripheral edge of the opening. Part is closed from the outer peripheral side, and a resin intermediate block constituting a main liquid chamber in which the inner volume changes due to deformation of the elastic body in the hollow portion, provided between the inner cylinder and the outer cylinder, at least the partition wall A sub liquid chamber partly composed of a diaphragm and a main liquid chamber formed in an intermediate block Those having a restricted passage for communicating the liquid chamber with each other. In the vibration isolator having such a structure, for example, a groove is formed on the outer peripheral surface of the intermediate block that is pressed against the inner peripheral surface of the outer cylinder, and this groove forms one of the restriction passages (shake orifice) for absorbing shake vibration. The section is configured, and by adopting such a layout, the path length of the shake orifice can be made sufficiently long.

[0006]

However, in the above-described vibration isolator, the intermediate block, which is a partition member, is usually molded using resin as a material, and the intermediate block can be molded with high dimensional accuracy. difficult. For this reason, a gap may be formed between the outer peripheral surface of the intermediate block and the inner peripheral surface of the outer cylinder, and liquid leakage may occur from the groove of the intermediate block. When such a leak occurs, for example, a portion of the liquid moves along a path that short-circuits the shake orifice, thereby substantially shortening the path length of the shake orifice. By moving along different paths, the flow resistance of the liquid between the main liquid chamber and the sub liquid chamber is reduced. As a result, the anti-shake effect of the anti-shake device is reduced, and the shake vibration cannot be sufficiently reduced.

Therefore, in the above-described vibration isolator, for example, a groove portion forming a part of a shake orifice with a rubber sealing member interposed between the outer peripheral surface of the intermediate block and the inner peripheral surface of the outer cylinder. However, if such a sealing member is disposed between the intermediate block and the outer cylinder, the number of parts increases, the number of assembly steps increases, and the manufacturing cost increases. In such a case, the seal member may be deteriorated or damaged by the liquid pressure, thereby deteriorating the sealing performance, and the vibration-proof performance against shake vibration may be reduced.

In view of the above, an object of the present invention is to reduce vibration damping performance due to liquid leakage from an outer peripheral groove formed in an intermediate block without disposing a seal member between the intermediate block and an outer cylinder. An object of the present invention is to provide an anti-vibration device that can prevent the vibration.

[0009]

According to the vibration isolator of the present invention, at least a part of the partition member extends in the circumferential direction to the outer peripheral surface of the partition member which is in pressure contact with the outer cylinder and becomes a part of the restricted passage. In addition to forming the outer peripheral groove, the outer peripheral surface of the partition member is provided with a protrusion extending along the axially central groove end of the outer peripheral groove on the outer peripheral surface. In the pressure-contacted state, the protrusion extending along the axially central groove end of the outer circumferential groove can be pressure-bonded to the inner circumferential surface of the outer cylinder so that there is no gap between the outer circumferential groove and the liquid in the outer circumferential groove. And leaking toward the axial center through the space between the outer cylinder and the inner peripheral surface of the outer cylinder. On the other hand, on the outer side in the axial direction of the outer circumferential groove, since the flange portion of the intermediate cylinder is in pressure contact with the inner circumferential surface of the outer cylinder, the liquid in the outer circumferential groove is formed between the outer circumferential surface of the partition member and the inner circumferential surface of the outer cylinder. Even if it leaks axially outside through
Since this liquid does not flow outside the flange portion of the intermediate cylinder, a liquid passage that short-circuits the restriction passage is not formed, and a liquid passage different from the restriction passage is not newly formed. As a result, it is possible to prevent a decrease in vibration isolation performance due to liquid leakage from an outer peripheral groove formed on the outer peripheral surface of the partition member.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vibration isolator according to an embodiment of the present invention will be described below with reference to the drawings.

(Structure of Embodiment) As shown in FIGS. 1 and 2, the so-called bush type vibration damping device 10 is provided with a ring-shaped mounting frame 12 for connection to a vehicle body (not shown). In this mounting frame 12, a cylindrical outer cylinder 16 is fitted and arranged. An outer peripheral portion of a rubber-made thin first diaphragm 20 is vulcanized and bonded to a metal bracket 14, and this first diaphragm 20 is disposed on the inner peripheral surface side of the outer cylinder 16 in the upper part in FIGS. 1 and 2. Have been. As shown in FIGS. 1 and 2, an air chamber 31 is provided between the first diaphragm 20 and the outer cylinder 16 and communicates with the outside as needed.

An intermediate cylinder 22 and an intermediate block 24 are inserted into the outer cylinder 16, and each of the intermediate cylinder 22 and the intermediate block 24 constitutes a partition member.
The intermediate block 24 has a substantially semicircular block shape when viewed from the axial direction of the outer cylinder 16. As shown in FIG. 1, the outer peripheral surface 24 </ b> C of the intermediate block 24 is in close contact with the inner peripheral surface of the outer cylinder 16. ing. As shown in FIG. 2, flange portions 22 </ b> A are formed at both ends in the axial direction of the intermediate cylinder 22, respectively.
The opening 2 formed between the pair of flanges 22A
3, the intermediate block 24 is fitted into the inner cylinder 26 side. The outer peripheral surfaces of the pair of flange portions 22 </ b> A are in close contact with the inner peripheral surface of the outer cylinder 16.

As shown in FIGS. 1 and 2, the portion of the intermediate cylinder 22 facing the flat portion 24B which is the upper surface of the intermediate block 24 is hollow, and the inside of this hollow is connected to an engine (not shown). The tube 26 penetrates. This inner cylinder 2
6 is arranged in parallel with the outer cylinder 16, and an elastic body 28 formed of a rubber material or the like is stretched between the outer cylinder 16 and the intermediate cylinder 22. Thus, the inner cylinder 26 can be moved relative to the outer cylinder 16.

That is, the inner cylinder 26 connected to the engine, which is a vibration generating section, is a first mounting member, and the outer cylinder 16 connected to the vehicle body, which is a vibration receiving section, via the mounting frame 12.
Is a second mounting member.

Further, the elastic body 28 also extends on the outer peripheral surface between the flange portions 22A of the intermediate cylinder 22, and protrudes from both ends of the intermediate block 24 on the inner peripheral side of the arc-shaped portion. A part of the elastic body 28 is in close contact with the inner circumferential arc surface 24A. Further, a hollow portion 28A is formed at an intermediate portion of the elastic body 28 and below the inner cylinder 26, and a space between the hollow portion 28A and the intermediate block 24 is a main liquid chamber 30.
It has been.

On the other hand, a pair of flange portions 22 of the intermediate cylinder 22
Between A, a first sub liquid chamber 32 surrounded by the intermediate cylinder 22 and the first diaphragm 20 is formed. Also,
As shown in FIG. 4, a U-shaped outer circumferential groove 46 is formed on the outer circumferential surface 24C of the intermediate block 24. One end of the outer peripheral groove 46 opens to the right end of the intermediate block 24 in FIG. 1 and is connected to the first auxiliary liquid chamber 32. The other end of the outer peripheral groove 46 communicates with the main liquid chamber 30 through a through hole 48 formed through the inside of the intermediate block 24. The outer peripheral groove 46 and the through hole 48 form a shake orifice 64 as a restriction passage for absorbing shake vibration.

A circular hole 34 is formed on the plane portion 24B side of the intermediate block 24, and a circular hole 3 is formed at the bottom of the circular hole 34.
A circular through hole 35 having a diameter smaller than that of the circular hole 4 and penetrating the outer peripheral surface 24 </ b> C of the intermediate block 24 is formed coaxially with the circular hole 34. The outer cylinder 16 of the intermediate block 24
A counterbore 39 is provided on the side coaxially with the circular through hole 35, and a seal O is provided outside the counterbore 39.
A ring 41 is fitted.

The circular hole 34 and the circular through hole 35 have:
A rotor 36 as a valve is rotatably inserted.
The main liquid chamber 30 side of the rotor 36 has a cylindrical cylindrical portion 36A.
On the opposite side of the cylindrical portion 36A, a thin shaft portion 36B as a rotating shaft is integrally provided. Further, a lid plate 40 also serving as a washer is fixed to the plane portion 24B side of the intermediate block 24 to prevent the rotor 36 from coming off.

A pair of O-rings 44 are fitted around the outer periphery of the thin shaft portion 36B. Therefore, this O
The liquid does not leak out of the intermediate block 24 through the circular through hole 35 by the ring 44.

Further, the cylindrical portion 36A of the rotor 36 has
A through-hole 38 communicating the inside and outside of the cylindrical portion 36A is formed. On the other hand, a passage 56 is formed in the intermediate block 24 such that one end is connected to the circular hole 34 and extends in a direction perpendicular to the plane of FIG. That is, one end of the passage 56 is opened in the inner periphery of the circular hole 34.

As shown in FIG. 5, the other end of the passage 56 communicates with one end of a passage 58 which is a groove formed in the outer periphery of the intermediate block 24 along the circumferential direction.
The other end of 8 communicates with the first sub liquid chamber 32. Accordingly, when the rotor 36 rotates and the through hole 38 of the rotor 36 faces the passage 56, the main liquid chamber 30 and the first sub liquid chamber 32 are communicated by the passages 56 and 58. .

That is, the passages 56 and 58 constitute an idle orifice 60 which communicates the main liquid chamber 30 and the first sub liquid chamber 32 and serves as a restriction passage for absorbing idle vibration.

On the other hand, as shown in FIG.
4 further includes a passage 56 along the radial direction of the circular hole 34.
Hole 92 is formed in the opposite direction.
In the portion of the intermediate block 24 corresponding to the opening end of the hole 92, a second auxiliary liquid chamber 9 defined as an arc-shaped space is provided.
6 is formed, and the end of the hole 92 for opening is opened to the second auxiliary liquid chamber 96. Therefore, when the rotor 36 rotates and the through-hole 38 faces the hole 92 for stagnation as shown in FIG. 1, the communication between the main liquid chamber 30 and the second sub-liquid chamber 96 is established. Become.

That is, the squeezing hole 92 connects the main liquid chamber 30 and the second sub-liquid chamber 96 to limit the passage for absorbing the medium-to-low-speed muffled sound which is higher in frequency than idle vibration. The orifice 62 for retraction is formed.

A thin rubber-made second diaphragm 94 is provided on the outer peripheral side of the intermediate block 24 with respect to the second sub liquid chamber 96, and the outer peripheral portion is provided between the outer cylinder 16 and the intermediate block 24. The second diaphragm 94 is an elastically deformable partition wall of the second sub liquid chamber 96.

For this reason, the space between the second diaphragm 94 and the inner peripheral surface side of the outer cylinder 16 is defined as a second air chamber 98 built in the outer cylinder 16 and filled with gas. The second air chamber 98 enables the deformation of the second diaphragm 94.

That is, the second diaphragm 94 constitutes a part of the partition wall of the second auxiliary liquid chamber 96. As shown in FIG. 1, the area of the second diaphragm 94 is equal to that of the first auxiliary liquid chamber 96. The first diaphragm 20 which constitutes a part of the partition wall 32
Is smaller than the area of the second diaphragm 9.
4 has higher rigidity than the first diaphragm 20.

The main liquid chamber 30, the first sub liquid chamber 32, and the second sub liquid chamber 96 are sealed so as to be filled with a liquid such as ethylene glycol.

On the other hand, a motor 70 as an actuator is provided outside the mounting frame 12. The tip of the rotating shaft 71 of the motor 70 is fitted to the tip of the thin shaft portion 36B of the rotor 36. The motor 70 is provided with a flange portion 70B, and the flange portion 70B is formed in an arc shape along the outer diameter of the mounting frame 12. Therefore, the motor 70 is fixed to the mounting frame 12 by screwing a screw (not shown) inserted through the flange portion 70B into a screw portion (not shown) provided on the mounting frame 12.

With the above-described structure, the rotor 36 is rotated, and as shown in FIG.
When the confined orifice 62 is opened, the main liquid chamber 30 and the second sub liquid chamber 96 are communicated via the confined orifice 62. Further, from this position, the rotor 36 is moved about 18
When rotated through 0 ° and the through hole 38 of the cylindrical portion 36A opens the idle orifice 60 as shown in FIG. 5, the main liquid chamber 30 and the first sub liquid chamber 32 are communicated via the idle orifice 60. You.

As described above, the arrangement in which the rotor 36 communicates between the main liquid chamber 30 and the first sub liquid chamber 32 through the idle orifice 60 as shown in FIG. 5 and the confinement as shown in FIG. It is rotated by the motor 70 so as to selectively adopt an arrangement for communicating between the main liquid chamber 30 and the second sub liquid chamber 96 via the orifice 62.

The motor 70 is connected to a controller 72 as control means, and its rotation is controlled by the controller 72. Controller 7
2 is operated by a vehicle power supply and has at least a vehicle speed sensor 7
4 and a detection signal from the engine speed detection sensor 76, the vehicle speed and the engine speed are detected, and it is possible to determine whether idle vibration or shake vibration has occurred.

Next, the seal structure of the shake orifice 64 and the main liquid chamber 30 in the vibration isolator 10 according to the present embodiment will be described.

As described above, an outer peripheral groove 46 (see FIG. 4) which forms a part of the shake orifice 64 is formed in a U-shape on the outer peripheral surface 24C of the intermediate block 24.
The outer circumferential groove 46 includes a pair of circumferential grooves 46A and 46B extending in the circumferential direction of the outer cylinder 16, and the pair of circumferential grooves 46A and 46B are disposed at both axial ends of the intermediate block 24, respectively. I have. Further, two projections 82 and 84 are formed on the outer peripheral surface 24C of the intermediate block 24 along the axially inner groove ends of the pair of peripheral grooves 46A and 46B.
Are integrally formed. Here, the intermediate block 24
Is formed of a curved surface having a radius of curvature of about 49 mm, and has a width along the axial direction of about 45 mm. On the other hand, the protrusion length of the protrusions 82 and 84 from the outer peripheral surface 24C is about 0.1 mm, and the width along the axial direction is 1.5 mm.
Degree. As shown in FIG. 7, a part of the elastic body 28 extends on the outer peripheral surfaces of the pair of flange portions 22A in the intermediate cylinder 22 inserted into the outer cylinder 16 together with the intermediate block 24. And thin film-shaped seal portion 86
Are formed.

As shown in FIG. 7, the intermediate block 24
Is inserted into the outer cylinder 16 together with the intermediate cylinder 22. The intermediate block 24 and the intermediate cylinder 22 are fixed to the outer cylinder 16 by caulking the outer cylinder 16 by a predetermined amount toward the inner peripheral side. Also, as shown in FIG. 8, the outer cylinder 16 is crimped to the inner peripheral side so that the outer peripheral surface 2 of the intermediate block 24 is
4C is pressed against the inner peripheral surface of the outer cylinder 16 and the outer peripheral side of the outer peripheral groove 46 formed on the outer peripheral surface 24C is closed by the inner peripheral surface of the outer cylinder 16.

When a substantially uniform pressing force is applied to the entire outer cylinder 16 from the outer peripheral side and the outer cylinder 16 is caulked toward the inner peripheral side, the rigidity of the flange portion 22A of the intermediate cylinder 22 is relatively smaller than the rigidity of the intermediate block 24. Outer cylinder 1 after caulking is completed
In No. 6, the outer diameter at both ends in the axial direction is slightly larger than the outer diameter at the central portion in the axial direction. At this time, as shown in FIG. 8, the outer cylinder 16 presses against the intermediate block 24 at the outer peripheral ends of the two projections 82 and 84 and the axial center of the outer peripheral surface 24C, respectively. The first and second flange portions 22 </ b> A of the intermediate cylinder 22 are pressed into contact with each other through the portions 86. As a result, the projections 82 and 84 extending along the axial end of the outer circumferential groove 46 are pressed together so that no gap is formed in the inner circumferential surface of the outer cylinder 16.

As shown in FIG. 2, the inner peripheral surface 24D of the intermediate block 24 is
Are pressed against each other via the lid plate 40. As shown in FIG. 1, a pair of inner circular arc surfaces 24 </ b> A of the intermediate block 24 are in pressure contact with the peripheral edge of the opening 23 in the outer peripheral surface of the intermediate cylinder 22 via the thin-film elastic body 28. As a result, the outer peripheral side of the cavity 28A formed in the elastic body 28 facing the opening 23 is closed by the intermediate block 24, and the main liquid chamber 30 partitioned from the outside is formed.
Is formed.

Here, as shown in FIG.
A thin film portion 88 and a seal portion 86 formed by extending a portion of the elastic body 28 from the inner circumferential side to the flange portion 22A through the opening portion 23 are vulcanized and bonded to the outer peripheral side of the second member 2. A thin film portion 88 is provided on the periphery of the opening 23 in the intermediate cylinder 22.
Is provided with a rib-shaped ridge portion 90 which is partially thick and extends in the circumferential direction. Thereby, both ends in the axial direction of the inner peripheral surface 24 </ b> D of the intermediate block 24 are kept in a state where the ridge portion 90 is compressed to the inner peripheral side, and the opening portion 23 in the intermediate cylinder 22 via the compressed ridge portion 90.
Is pressed against the periphery of

Next, the operation of the present embodiment will be described.

When the engine mounted on the inner cylinder 26 operates, the vibration of the engine is transmitted to the elastic body 28 via the inner cylinder 26. The elastic body 28 acts as a vibration absorbing main body, and can absorb vibration by a vibration damping function based on internal friction of the elastic body 28.

Further, the liquids in the main liquid chamber 30 and the first sub liquid chamber 32, whose internal volumes change with the deformation of the elastic body 28 and the first diaphragm 20, are passed through the shake orifice 64 or the idle orifice 60. The liquids in the main liquid chamber 30 and the second sub liquid chamber 96, which flow mutually and whose internal volumes change with the deformation of the elastic body 28 and the second diaphragm 94, are mutually interposed through the orifice 62. And the damping action based on the viscous resistance of the liquid flow generated in these orifice spaces and the liquid column resonance can improve the vibration isolation effect.

Specifically, for example, when the vehicle is 70 to 80 km /
Shake vibration (about 10Hz) when driving at high speeds
Occurs. The controller 72 determines whether or not a shake vibration has occurred based on a vehicle speed sensor 74 and an engine speed detection sensor 76. When the controller 72 determines that shake vibration is occurring, the controller 72
0, the rotor 36 is rotated, and as shown in FIG. 1, the through-hole 38 is made to correspond to the
The arrangement does not correspond to the idle orifice 60.

As a result, the idle orifice 60 is closed, the normally open shake orifice 64 communicates the main liquid chamber 30 with the first sub liquid chamber 32, and the confinement orifice 62 connects the main liquid chamber 30 with the first liquid chamber 30. Second sub liquid chamber 96
And communicate with.

As a result, the pressure change based on the engine vibration generated in the main liquid chamber 30 is transmitted to the liquid in the shake orifice 64 and the orifice 62, and the vibration of the liquid is absorbed by the resistance of the liquid and the like.

Furthermore, a medium-to-low-speed muffled sound (80%) which is a high-frequency, small-amplitude vibration that may be generated together with the shake vibration.
(About Hz), the liquid column resonates in the muffled orifice 62 and the dynamic spring constant is reduced, and muffled sound is absorbed.

When the engine is idling or the vehicle speed is 5 km / h or less, the idle vibration (25
Hz). The controller 72 is a vehicle speed sensor 7
4. The engine speed detection sensor 76 not only determines whether or not idle vibration occurs, but also determines whether the generated idle vibration is low idle vibration or high idle vibration.

When the controller 72 determines that the idle vibration is occurring, the controller 72 rotates the motor 70 and, as shown in FIG.
Are arranged so as to correspond to the idle orifice 60 and do not correspond to the orifice 62.

As a result, the orifice 62 is closed, and the liquid having a small inside diameter and the liquid passing through the idle orifice 60 having a large passage resistance is connected to the main liquid chamber 30 and the first sub liquid chamber 32.
As a result, the liquid spring resonates in the idle orifice 60 and the dynamic spring constant is reduced, and the low idle vibration is absorbed.

That is, the three orifices 60, 61 and 62, which can communicate with the main liquid chamber 30 and the sub liquid chambers 32 and 96 to reduce vibration, are selectively provided by the rotor 36 driven by the motor 70. By opening and closing, vibrations at three different frequencies can be reduced.
As a result, the vibration is appropriately absorbed at any vibration frequency, and a wide range of vibration can be reduced.

The anti-vibration device 1 according to the embodiment described above.
According to No. 0, the outer peripheral surface 24C of the intermediate block 24 is provided with the two protrusions 82 and 84 along the axially inner groove ends of the two peripheral groove portions 46A and 46B. In a state where the surface 24 </ b> C is pressed against the inner peripheral surface of the outer cylinder 16, the protrusions 82 and 84 extending along the axially central groove end of the outer peripheral groove 46 are formed so that there is no gap in the inner peripheral surface of the outer cylinder 16. Therefore, it is possible to prevent the liquid in the outer peripheral groove 46 from leaking toward the center in the axial direction through the space between the outer peripheral surface 24C of the intermediate block 24 and the inner peripheral surface of the outer cylinder 16. On the other hand, on the outside of the outer circumferential groove 46 in the axial direction,
Is pressed into contact with the inner peripheral surface of the outer cylinder 16 via the seal portion 86, so that the liquid in the outer peripheral groove 46 can flow between the outer peripheral surface 24C of the intermediate block 24 and the inner peripheral surface of the outer cylinder 16. Even if the liquid leaks out in the axial direction through the gap, the liquid does not flow out in the axial direction from the flange portion 22A of the intermediate cylinder 22, so that a liquid passage for short-circuiting the shake orifice 64 is formed, or the shake orifice is formed. A new liquid passage different from 64 is not formed. As a result, the outer peripheral groove 46 formed on the outer peripheral surface 24C of the intermediate block 24 is formed.
Of the vibration isolating performance due to the liquid leakage from the liquid can be prevented.

In the vibration isolator 10 according to the present embodiment, the elastic body 2 is provided on the peripheral portion of the opening 23 in the intermediate cylinder 22.
A ridge portion 90 is formed integrally with the base block 8 and extends in the circumferential direction. The ridge portion 90 is pressed against the inner peripheral surface 24D of the intermediate block 24, and the inner peripheral arc surface 24A of the intermediate block 24 is also formed as a thin film. And presses against the outer peripheral surface of the intermediate cylinder 22 via the elastic body 28. As a result, the gap between the periphery of the opening 23 in the intermediate cylinder 22 and the intermediate block 24 can be sealed by the ridge 90 and the elastic body 28 in a compressed state, so that the liquid in the main liquid chamber 30 leaks through the opening. Can be effectively prevented. Further, since the ridge portion 90 is formed integrally with the elastic body 28, the number of components and the assembly process of the vibration isolator 10 do not increase.

In this embodiment, the intermediate block 24
The protrusion length of the projections 82 and 84 provided on the outer cylinder 24C is set to about 0.1 mm.
6 is appropriately set in the range of 0.1 to 1.0 mm in accordance with the amount of caulking, the elasticity and rigidity of the intermediate block 24, and the like.

The anti-vibration device 10 of this embodiment is of a switching type in which the rotor 36 is operated in accordance with the vibration frequency and the orifices 60 and 62 communicating with the main liquid chamber 30 are switched by the rotor 36. It goes without saying that the seal structure according to the present invention can be applied to any structure as long as the vibration isolator has a groove that forms an orifice on the outer peripheral surface of the intermediate block 24. Further, in the intermediate block 24 according to the present embodiment, one U-shaped curved groove portion 46 is formed on the outer peripheral surface 24C. However, if the groove portion forming the orifice extends in the circumferential direction, the groove portion may be formed. Irrespective of the number, the seal structure according to the present invention can be applied.

[0054]

As described above, according to the vibration isolator of the present invention, the liquid leakage from the outer peripheral groove formed in the intermediate block can be performed without disposing the seal member between the intermediate block and the outer cylinder. It is possible to prevent the vibration isolation performance from lowering.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along a radial direction showing a configuration of a vibration isolator according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the vibration isolator shown in FIG. 1 taken along section line 2-2.

FIG. 3 is a perspective view showing an intermediate block in the vibration isolator according to the embodiment of the present invention.

FIGS. 4A and 4B are diagrams showing an intermediate block in the vibration isolator according to the embodiment of the present invention, wherein FIG. 4A is a left side view, FIG. 4B is a bottom view, and FIG. It is.

FIG. 5 is a cross-sectional view along a radial direction showing a configuration of a vibration isolator according to the embodiment of the present invention.

FIG. 6 is a side sectional view showing the intermediate cylinder and the intermediate block in the vibration isolator according to the embodiment of the present invention, and shows a state before the opening of the intermediate cylinder is closed by the intermediate block.

FIG. 7 is a side sectional view showing the intermediate cylinder and the intermediate block inserted into the outer cylinder in the vibration isolator according to the embodiment of the present invention, showing a state before the outer cylinder is crimped to the inner peripheral side. I have.

FIG. 8 is a side cross-sectional view showing the intermediate cylinder and the intermediate block inserted into the outer cylinder in the vibration isolator according to the embodiment of the present invention, and shows a state after the outer cylinder is crimped to the inner peripheral side. ing.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Vibration isolator 16 Outer cylinder 22 Intermediate cylinder 22A Flange part 23 Opening part 24 Intermediate block (partition member) 26 Inner cylinder 28 Elastic body 28A Cavity part 30 Main liquid chamber 32 First sub liquid chamber 80 Outer peripheral groove 80A Peripheral groove part 80B Circumferential groove 82 Projection 84 Projection 90 Ridge

Claims (6)

[Claims] An inner cylinder connected to one of the vibration generator and the vibration receiver; an outer cylinder connected to the other of the vibration generator and the vibration receiver; and an elasticity fixed to an outer peripheral surface of the inner cylinder. The body and the outer peripheral portion of the elastic body which are arranged on the outer peripheral side of the inner cylinder are fixed, and flange portions are provided at both ends in the axial direction, and the pair of flange portions are inserted into the outer cylinder. An intermediate cylinder, an opening formed between a pair of flanges in the intermediate cylinder, a concave cavity formed in the elastic body facing the opening, an inner peripheral surface of the outer cylinder, A partition member that constitutes a main liquid chamber in which the inner volume changes due to deformation of the elastic body in the hollow portion by pressing against the peripheral edge of the opening and closing the opening from the outer peripheral side; Provided between the outer cylinder, at least a part of the partition is elastically deformable A vibration isolator having a sub-liquid chamber and a restriction passage formed in the partition member and communicating the main liquid chamber and the sub-liquid chamber with each other, wherein an outer periphery of the partition member that is in pressure contact with the outer cylinder. On the surface, at least a portion extends in the circumferential direction to form an outer peripheral groove that becomes a part of the restriction passage, and a projection that extends along a groove end on the axial center side of the outer peripheral groove is provided. A vibration isolator characterized by the above-mentioned. 2. The outer peripheral groove is provided with two peripheral groove portions extending along the circumferential direction, and the outer peripheral surface of the partition member extends along an axially inner groove end of the two peripheral groove portions. The vibration isolator according to claim 1, wherein the two projections are provided as described above. 3. The outer cylinder has its inner peripheral surface pressed against the pair of flanges and the two projections, and the amount of deformation near the center of the two projections is maximized. The vibration damping device according to claim 2, wherein the vibration damping device is caulked to an inner peripheral side. 4. The anti-vibration device according to claim 1, wherein a length of the protrusion from the press contact surface is set to 0.1 mm or more and 1.0 mm or less. 5. A rib-shaped ridge formed of an elastic material and extending in the circumferential direction is provided on a peripheral edge of the opening in the intermediate cylinder, and the ridge is pressed against the partition member. The vibration isolator according to claim 1, 2, 3, or 4. 6. The vibration isolator according to claim 5, wherein the ridge portion is formed integrally with the elastic body.