WO2019093367A1

WO2019093367A1 - Anti-vibration device

Info

Publication number: WO2019093367A1
Application number: PCT/JP2018/041323
Authority: WO
Inventors: 小島　宏
Original assignee: 株式会社ブリヂストン
Priority date: 2017-11-08
Filing date: 2018-11-07
Publication date: 2019-05-16

Abstract

An anti-vibration device in which: elastic bodies (31, 32) comprise center elastic bodies (32) arranged separately on both sides in the radial direction sandwiching an inner attachment member (11); a covering member (17) is arranged between the inner attachment member and an outer cylinder (12), the covering member (17) covering, from the outer side in the radial direction, the space between the center elastic bodies, which are adjacent in the circumferential direction, and demarcating from the inner attachment member two liquid chambers (14a, 14b); an orifice passage is formed between the covering member and the outer cylinder, the orifice passage communicating between the two liquid chambers; the two liquid chambers are filled with a liquid having a dynamic viscosity of 50 cSt or more at 40°C; and shunting through-holes (21, 22, 23, 24) are formed in the wall surface of the orifice passage.

Description

Vibration control device

The present invention relates to a vibration isolation device.
Priority is claimed on Japanese Patent Application No. 2017-215408, filed on Nov. 8, 2017, and Japanese Patent Application No. 2017-215413, filed on Nov. 8, 2017. Insist and use the contents here.

Conventionally, the inner mounting member is connected to one of the vibration generating portion and the vibration receiving portion, the other is connected to any one of the vibration generating portion and the vibration receiving portion, and the inner mounting member is radially And an elastic body that elastically connects the inner mounting member and the outer cylinder, wherein the elastic bodies are separately disposed on both sides of the inner mounting member in the radial direction, A covering member is provided between the mounting member and the outer cylinder, covering between the elastic bodies adjacent to each other in the circumferential direction from the outside in the radial direction and defining a liquid chamber, and between the covering member and the outer cylinder There is known a vibration control device in which an orifice passage communicating each liquid chamber is formed.

Japanese Patent Application Laid-Open No. 2016-133181

However, in the above-described conventional vibration damping device, when a liquid with high viscosity is sealed in the liquid chamber, the internal pressure of the liquid chamber is easily increased and the dynamic spring constant is increased, and any one of the liquid chambers When the internal pressure exceeds a predetermined value, the liquid in the one liquid chamber may leak.

The present invention has been made in consideration of such circumstances, and provides a vibration control apparatus capable of suppressing an increase in dynamic spring constant, leakage of liquid, and the like even if a liquid with high viscosity is enclosed in a liquid chamber. The purpose is

According to a first aspect of the present invention, there is provided a vibration damping device comprising an inner mounting member connected to any one of a vibration generating unit and a vibration receiving unit, and any one of a vibration generating unit and a vibration receiving unit. An outer cylinder that is coupled and that surrounds the inner attachment member, and an elastic body that elastically connects the inner attachment member and the outer cylinder, and the elastic body is at the central axis of the outer cylinder. A middle elastic body separately disposed on both sides sandwiching the inner mounting member in the radial direction intersecting the central axis in plan view seen from the axial direction along, and between the inner mounting member and the outer cylinder Between the middle elastic bodies adjacent to each other in the circumferential direction around the central axis in the plan view and from the outside in the radial direction to define two liquid chambers between the middle attachment and the inner mounting member A covering member is disposed, and the second member is disposed between the covering member and the outer cylinder. The liquid chamber between the orifice passage communicating are formed, said two liquid chambers, kinematic viscosity at 40 ° C. is encapsulated or liquid 50 cSt, short through hole in the wall of the orifice passage.

According to the vibration control device of the present invention, even if a high viscosity liquid is sealed in the liquid chamber, it is possible to suppress an increase in dynamic spring constant, leakage of the liquid, and the like.

It is a cross-sectional view in the axial direction center part of the vibration isolator shown as one embodiment concerning the present invention. FIG. 2 is a cross-sectional view of the vibration control device shown in FIG. FIG. 2 is a cross-sectional view of the vibration control device shown in FIG. FIG. 6 is a side view of one of two boundary portions of two covering members as viewed from the outer side in the radial direction in the vibration damping device shown in FIGS. 1 to 3 with the outer cylinder removed. The vibration isolator shown in FIGS. 1 to 3 is a side view in which the other of two boundary portions of two covering members is viewed from the outside in the radial direction with the outer cylinder removed. FIG. 6 is a side view of the intermediate elastic body in a front view with the cover member removed in the vibration control device shown in FIGS. 4 and 5. FIG. 5 is a side view of the anti-vibration device shown in FIG. 4 and FIG.

Hereinafter, an embodiment of a vibration damping device according to the present invention will be described with reference to FIGS. 1 to 7.
The vibration control device 1 according to the present embodiment is connected to the inner mounting member 11 connected to one of the vibration generating unit and the vibration receiving unit, and to the other of the vibration generating unit and the vibration receiving unit. In addition, an outer cylinder 12 surrounding the inner attachment member 11 and

elastic bodies

31 and 32 elastically connecting the inner attachment member 11 and the outer cylinder 12 are provided.
The vibration damping device 1 is used as, for example, a suspension bush or an engine mount for a car, or a mount of an industrial machine installed in a factory.
Hereinafter, a direction along the central axis O of the outer cylinder 12 is referred to as an axial direction, and a direction intersecting the central axis O is referred to as a radial direction in plan view viewed from the axial direction. It is called a direction.

As shown in FIGS. 1 to 3, the inner attachment member 11 is formed in a cylindrical shape coaxially disposed with the central axis O. At an axially intermediate portion of the inner mounting member 11, a bulging portion 15 that bulges outward in the radial direction is formed over the entire circumference. The bulging portion 15 is formed at the central portion in the axial direction of the inner mounting member 11. The radially outwardly facing top surface 15 a of the bulging portion 15 extends in the circumferential direction and also in the axial direction. The bulging portion 15 is disposed inside the outer cylinder 12. The inner diameter of the inner mounting member 11 is equal over the entire length in the axial direction. Both axial end portions of the inner mounting member 11 protrude outward in the axial direction from the outer cylinder 12.

The

elastic bodies

31 and 32 are made of a rubber material, and are adhered by vulcanization to the outer peripheral surface of the inner mounting member 11. The

elastic bodies

31 and 32 are arranged at intervals in the axial direction, and are arranged between a pair of end elastic bodies 31 fitted in the outer cylinder 12 and the end elastic bodies 31, in the circumferential direction. And a pair of middle elastic bodies 32 spaced apart from each other.

The end elastic body 31 extends radially inward from both axial end portions of the top surface 15 a of the surface of the bulging portion 15 and is separately disposed on both end surfaces 15 b facing the axial direction. The end face 15 b extends outward in the axial direction gradually inward in the radial direction from the top face 15 a. The end elastic body 31 extends in the radial direction from the axial outer end of the cylindrical portion 31a, which gradually extends outward in the radial direction from the end face 15b of the bulging portion 15 toward the outer side in the axial direction. And a flange portion 31b that protrudes toward the outside of the and extends continuously over the entire circumference. The cylindrical portion 31 a and the flange portion 31 b are disposed coaxially with the central axis O. The flange portion 31 b is located on the inner side in the axial direction from the end in the axial direction of the inner mounting member 11. An annular reinforcing plate 33 is embedded in the flange portion 31b. The reinforcing plate 33 is formed of, for example, a hard material such as a metal material or a synthetic resin material. The pair of end elastic bodies 31 have the same shape and the same size.

The middle elastic body 32 is separately disposed on both sides of the inner mounting member 11 in the radial direction. The middle elastic body 32 is formed of a rubber material over the entire area. The middle elastic body 32, as shown in FIG. 6, projects separately from the main portion 32a disposed at the axial center of the inner attachment member 11 and outward from the main portion 32a in the axial direction, and And a pair of sub-portions 32b smaller in volume than the main portion 32a. Each of the main portion 32a and the sub portion 32b has a rectangular shape in which a pair of side portions extend in the circumferential direction and a remaining pair of side portions extend in the axial direction in a front view as viewed from the outer side in the radial direction. Sub part 32 b is connected to the circumferential center part of main part 32 a. The axial outer end of the sub portion 32 b is connected to the flange portion 31 b of the end elastic body 31. The radially outer surface of each of the main portion 32a and the sub portion 32b is a flat surface extending in both the transverse and axial directions orthogonal to the axial direction in a front view viewed from the radially outer side. ing. The outer surfaces of the main portion 32a and the sub portion 32b are continuous without steps. The pair of middle elastic bodies 32 have the same shape and the same size. The circumferential size of the main portion 32a is larger than the circumferential size of the sub portion 32b. The axial size of the main portion 32a is smaller than the axial size of the sub portion 32b.

Here, as shown in FIG. 1, in the bulging portion 15 of the inner mounting member 11, the stopper portion 16 positioned between the middle elastic bodies 32 adjacent to each other in the circumferential direction is directed radially inward. A recessed portion 16a is formed. The recess 16 a is formed in the shape of a groove extending in the axial direction. The recess 16a has a rectangular shape that is long in the axial direction when viewed from the outer side in the radial direction. The stopper portion 16 is formed to be able to abut on the inner surface (the inner peripheral surface side of the outer cylinder 12) of the covering member 17 described later when the inner mounting member 11 and the outer cylinder 12 move relatively close to each other. The stopper portion 16 is located radially outward of the other portions of the bulging portion 15, and the top surface 15 a of the bulging portion 15 has an oval shape in a plan view as viewed from the axial direction. The top surface 15 a of the stopper portion 16 is formed in an arc shape centering on the central axis O in the plan view.

The recessed portion 16 a is formed at an intermediate portion in the circumferential direction of the stopper portion 16. In the illustrated example, the recess 16 a is formed at the center of the stopper 16 in the circumferential direction. As shown in FIG. 2, the recessed portion 16 a is formed in the top surface 15 a of the stopper portion 16 in a portion positioned inward in the axial direction from both end edges in the axial direction. That is, both axial end portions of the recessed portion 16 a are not open to the both end surfaces 15 b of the stopper portion 16. In the illustrated example, the recessed portion 16 a is formed in the top surface 15 a of the stopper portion 16 in a portion positioned inward in the circumferential direction from both end edges in the circumferential direction. The opening of the recess 16a is formed in a convex curved shape. The recessed portion 16 a is formed in a concave surface shape which is recessed inward in the radial direction in a cross-sectional view orthogonal to the central axis O. A portion of the top surface 15a of the stopper portion 16 located between the opening of the recess 16a and the axial end edge of the top surface 15a is axially straight in a longitudinal sectional view along the axial direction. It extends in the shape of

In the present embodiment, the stopper elastic portion 34 covering the stopper portion 16 is provided. The stopper portion 16 and the stopper elastic portion 34 are disposed between the middle elastic bodies 32 adjacent to each other in the circumferential direction. The stopper elastic portion 34 and the

elastic bodies

31, 32 are integrally formed of, for example, a rubber material or the like. The outer peripheral surface of the inner mounting member 11 is covered with, for example, a rubber material over the entire area.

As shown in FIG. 1, in the stopper elastic portion 34, an outer portion 34b located on the outer side in the circumferential direction than the inner portion 34a covering the depressed portion 16a of the stopper portion 16 protrudes radially outward from the inner portion 34a. There is. The outer surface of the inner portion 34 a is formed in an arc shape centered on the central axis O. The outer surface of the outer portion 34b is formed in the shape of a curved surface protruding outward in the radial direction. In a cross-sectional view perpendicular to the central axis O, the radius of curvature of the outer surface of the inner portion 34a is larger than the radius of curvature of the outer surface of the outer portion 34b. The axial sizes of the outer portion 34b and the main portion 32a of the middle elastic body 32 are equal to each other, and the axial positions of the outer portion 34b and the main portion 32a are equal to each other.

The inner portion 34a and the outer portion 34b are circumferentially separated. This divided portion (hereinafter referred to as the first divided portion) 34c is formed over the entire axial length of each connecting portion of the inner portion 34a and the two outer portions 34b in the stopper elastic portion 34, as shown in FIG. It is done. Both axial end portions of the first divided portion 34c are located axially outside of both axial end portions of the outer portion 34b. Both end portions in the axial direction of the first divided portion 34 c are located on the top surface 15 a of the stopper portion 16 at a portion located axially outside the recessed portion 16 a. As shown in FIG. 1, in the top surface 15a of the stopper portion 16, the first divided portion 34c is disposed at a position circumferentially away from both the circumferential end edges and the opening of the recess 16a. ing.
The first divided portion 34 c penetrates the stopper elastic portion 34 in the radial direction, has a circumferential width, and is an elongated hole extending in the axial direction. The circumferential size of a portion of the inner portion 34a circumferentially sandwiched between the two first divided portions 34c is smaller than the circumferential size of the outer portion 34b.

As shown in FIGS. 2 and 7, the stopper elastic portion 34 and the end elastic body 31 are separated in the axial direction. The divided portion (hereinafter referred to as a second divided portion) 34d penetrates the stopper elastic portion 34 in the radial direction, has an axial width, and is an elongated hole extending in the circumferential direction. The second divided portions 34 d are formed at both axial end portions of the stopper elastic portion 34. The second divided portion 34 d axially divides the inner portion 34 a of the stopper elastic portion 34 and the end elastic body 31. The second divided portion 34d may axially divide the whole of the stopper elastic portion 34 including the inner portion 34a and the outer portion 34b and the end elastic body 31.

The axial outer end of the second divided portion 34d is located axially outside of the axial end of the outer portion 34b, and the axial inner end of the second divided portion 34d is located in the axial direction of the outer portion 34b. Located axially inward of the end of the. The second divided portion 34d is located on the top surface 15a of the stopper portion 16 at a position axially inside the axial end edge and at the outside axially of the opening of the recess 16a. . The second divided portion 34 d is disposed in a portion of the stopper elastic portion 34 located inward in the circumferential direction than the two outer portions 34 b.
In the illustrated example, the circumferential end of the second divided portion 34d is connected to the axial end of the first divided portion 34c, and the second divided portion 34d and the first divided portion 34c are radially outward. It has a rectangular frame shape as viewed from the side. The width of the second divided portion 34d is slightly larger than the width of the first divided portion 34c.

Between the inner attachment member 11 and the outer cylinder 12, the

liquid chambers

14a and 14b are defined between the middle elastic members 32 adjacent to each other in the circumferential direction from the outer side in the radial direction and between the inner attachment member 11. A covering member 17 is disposed. The covering member 17 is formed of, for example, a synthetic resin material or the like harder than the material forming the

elastic bodies

31 and 32. The stopper portion 16 and the stopper elastic portion 34 are disposed between the middle elastic bodies 32 adjacent to each other in the circumferential direction, and constitute a part of the partition walls of the

liquid chambers

14a and 14b.

In the

liquid chambers

14a and 14b, a liquid having a kinematic viscosity at 40 ° C. of 50 cSt or more and 1000 cSt or less, preferably 500 cSt or more and 1000 cSt or less is sealed. The measurement of the kinematic viscosity was performed using a B-type viscometer (manufactured by Tokimec Co., Ltd.) in accordance with JIS K2283. Examples of the liquid include silicone oil and the like.
The covering member 17 surrounds the inner mounting member 11 from the outer side in the radial direction over the entire circumference. The inner surface of the covering member 17 is in fluid-tight contact with the outer surface of the middle elastic body 32 and is not in contact with the stopper elastic portion 34.

Here, as shown in FIG. 2, of the outer surface of the stopper elastic portion 34 facing the inner surface of the covering member 17, at least the corresponding portion located on the recess 16 a and the inner surface of the covering member 17, At least a facing portion facing the corresponding portion of the outer surface of the stopper elastic portion 34 extends in the axial direction over the entire region in a longitudinal sectional view along the axial direction. In the illustrated example, the corresponding portion of the outer surface of the stopper elastic portion 34 and the opposed portion of the inner surface of the covering member 17 are substantially parallel in the longitudinal cross-sectional view.

Of the inner surface of the covering member 17, the portion facing the opening peripheral edge portion of the recess 16a in the top surface 15a of the stopper portion 16 via the stopper elastic portion 34 extends over the opposite portion along the axis in the longitudinal sectional view It extends in the direction. A portion of the inner surface of the covering member 17 which is radially opposed to the axial end of the stopper portion 16 via the stopper elastic portion 34 gradually extends outward in the radial direction toward the axial outer side. ing.

As shown in FIG. 1, of the inner surface of the covering member 17, a portion facing the outer surface of the inner portion 34 a of the stopper elastic portion 34 is formed in an arc shape centered on the central axis O, and the stopper elastic portion 34 is formed. The portion of the outer portion 34 b facing the outer surface is formed in the shape of a concave surface that is recessed outward in the radial direction. In a cross-sectional view perpendicular to the central axis O, the curvature radius of the portion of the inner surface of the covering member 17 facing the outer surface of the inner portion 34a of the stopper elastic portion 34 is the outer surface of the outer portion 34b of the stopper elastic portion 34. And the radius of curvature of the opposing part. Of the inner surface of the covering member 17, a portion facing the outer surface of the stopper elastic portion 34 is formed in a shape along the outer surface shape of the stopper elastic portion 34. In the cross-sectional view, a portion of the inner surface of the covering member 17 facing the outer surface of the stopper elastic portion 34 is substantially parallel to the outer surface of the stopper elastic portion 34.

A plurality of covering members 17 are disposed along the circumferential direction, and circumferential edges thereof abut each other to form a cylindrical shape as a whole. In the illustrated example, two covering members 17 are formed in a half cylindrical shape. The covering member 17 covers the middle elastic body 32 all around. The peripheral edge of the covering member 17 is located at the circumferential center of the middle elastic body 32.

The covering member 17 compresses and deforms the middle elastic body 32 radially inward and circumferentially inward. That is, compressive force is applied to the intermediate elastic body 32 in both the radial direction and the circumferential direction. In the illustrated example, at each end of the inner surface of one covering member 17 in the circumferential direction, pressing projections 17f are formed separately, which project radially inward and press against the circumferential end surface of the middle elastic body 32. ing. In the pressing protrusion 17f, the pressing surface pressed against the circumferential end surface of the middle elastic body 32 is a flat surface that faces the outer side in the circumferential direction of one covering member 17 and extends in the axial direction.

As shown in FIG. 4, on the outer peripheral surface of the covering member 17, a main communication groove 18, and one of the

liquid chambers

14 a and 14 b, a first communication opening 18 opened to the liquid chamber 14 a and the main groove 19. And the second communication opening 20 opened to the main body groove 19 and the other liquid chamber 14 b of the

liquid chambers

14 a and 14 b.

The first communication opening 18 and the second communication opening 20 are respectively formed at circumferential ends adjacent to each other in the circumferential direction in each of the two covering members 17.
As shown in FIGS. 4 and 5, in the outer peripheral surface of the covering member 17, the main body groove 19 extends from the one end portion in the circumferential direction where the first communication opening 18 or the second communication opening 20 is disposed. The first groove 19a extends toward the end, and the other end in the circumferential direction is disposed at a position axially separated from the first groove 19a, and both ends in the circumferential direction are open in the circumferential direction. And the second groove 19b. One end of the first groove 19a in the circumferential direction is closed in the circumferential direction by an end wall 19c extending in the axial direction.

The two covering members 17 are formed in the same shape and in the same size, and in the state in which the two covering members 17 are respectively reversed in the axial direction, the peripheral edges are arranged in a row in the circumferential direction.
Thereby, the other end of the first groove 19a in one covering member 17 in the circumferential direction and the other end of the second groove 19b in the other covering member 17 in the circumferential direction are connected to each other, and one covering member The one end portion of the second groove 19b in the circumferential direction 17 and the one end portion of the second groove 19b in the other covering member 17 are connected to each other, and the circumferential direction of the second groove 19b in one covering member 17 The other end of the first cover 19 and the other end in the circumferential direction of the first groove 19a of the other covering member 17 are connected to each other.

Here, as shown in FIG. 4, among the side surfaces in the circumferential direction of the end wall portion 19 c, the outer side surface 19 d located outside the first groove 19 a gradually increases in the axial direction as it is separated from the second groove 19 b, It extends to the outside of the first groove 19a. Thus, one end of the second groove 19 b in one covering member 17 in the circumferential direction and one end of the second groove 19 b in the other covering member 17 in the circumferential direction are end wall portions of the two covering members 17. It is connected through the gap between the outer surface 19d of 19c. The outer surfaces 19d of the end walls 19c of the two covering members 17 are substantially parallel to each other, and the gap linearly extends in a direction inclined in both the axial direction and the circumferential direction.

As the outer cylinder 12 is integrally fitted to the two covering members 17, the outer cylinder 12 and the inner mounting member 11 are elastically connected, and the main groove 19 and the inner peripheral surface of the outer cylinder 12 An orifice passage communicating the

liquid chambers

14a and 14b with each other is defined therebetween. The orifice passage communicates the

liquid chambers

14 a and 14 b with each other through the first communication opening 18 and the second communication opening 20. The orifice passage is extended between the covering member 17 and the outer cylinder 12 along the circumferential direction for one and a half or more. In the illustrated example, the orifice passage is extended between the covering member 17 and the outer cylinder 12 along substantially two rounds in the circumferential direction.
Then, when vibration is input to the vibration isolation device 1, the

elastic bodies

31, 32 elastically deform and the internal volumes of the

liquid chambers

14a, 14b fluctuate, so that the liquid in the

liquid chambers

14a, 14b is changed. The vibration is damped and absorbed by flowing through the orifice passage to cause liquid column resonance.

A first short-circuited through-hole for causing a liquid flowing in the orifice passage from one liquid chamber 14a to the other liquid chamber 14b to reach the wall surface defining the orifice passage by short circuiting the other liquid chamber 14b 21 and a second short-circuited through hole 22 is formed for causing a liquid flowing from the other liquid chamber 14 b to the one liquid chamber 14 a from the other liquid chamber 14 b to reach the one liquid chamber 14 a by a short circuit. There is.
The flow resistance of the liquid passing through the first short circuit through hole 21 and the second short circuit through hole 22 is smaller than the flow resistance of the orifice passage. Each flow passage cross-sectional area of the first short circuit through hole 21 and the second short circuit through hole 22 is, for example, about 3 mm ² or more, which is smaller than the flow passage cross sectional area of the orifice passage. Each length of the first short circuit through hole 21 and the second short circuit through hole 22 is shorter than the length of the orifice passage.

The first short circuit through hole 21 and the second short circuit through hole 22 are formed on the outer peripheral surface of the covering member 17 and are formed on the bottom of the main groove 19. The first short through holes 21 and the second short through holes 22 are separately formed in the two covering members 17. The first short circuit through hole 21 and the second short circuit through hole 22 are connected to the other end of the second groove 19b in the circumferential direction of the first groove 19a in the other covering member 17 among the two circumferential ends of the second groove 19b. It is formed at the other end. Thereby, in the other liquid chamber 14b, the first short circuit through hole 21 is provided at the rear end of the flow direction F1 in which the liquid flows from the one liquid chamber 14a toward the other liquid chamber 14b in the orifice passage. It is open. The second short circuit through hole 22 is opened at the rear end of the flow direction F2 in which the liquid flows from the other liquid chamber 14b toward the one liquid chamber 14a in the orifice passage in the one liquid chamber 14a. There is.

The first short circuit through hole 21 is disposed at a position about 180 degrees away from the first communication opening 18 along the flow direction F1 about the central axis O, and the second short circuit through hole 22 is formed from the second communication opening 20 It is disposed at a position about 180 ° apart from the central axis O along the flow direction F2.
The first short circuit through hole 21 and the second short circuit through hole 22 are disposed at the axial center of the second groove 19b. The opening shape at the groove bottom of the main body groove 19 in each of the first short circuit through hole 21 and the second short circuit through hole 22 is an elongated circular shape elongated in the circumferential direction.

It is located at the end on the rear side of the flow direction F1 in which the liquid circulates in the orifice passage from one liquid chamber 14a to the other liquid chamber 14b on the inner peripheral surface of the first short circuit through hole 21 The rear end face 21a facing the front side of F1 gradually extends toward the front side of the flow direction F1 as it goes from the radially outer side to the inner side. In the illustrated example, of the inner peripheral surfaces of the first short circuit through holes 21, the front end 21b located at the front end of the flow direction F1 and facing the back of the flow direction F1 is also from the outside in the radial direction As it goes, it gradually extends toward the front side of the flow direction F1. The rear end face 21a and the front end face 21b of the first short circuit through hole 21 are substantially parallel.

It is located at the end on the rear side of the flow direction F2 in which the liquid circulates in the orifice passage from the other liquid chamber 14b to the one liquid chamber 14a on the inner peripheral surface of the second short circuit through hole 22 The rear end surface 22a facing the front side of F2 gradually extends toward the front side in the flow direction F2 from the radially outer side toward the inner side. In the illustrated example, of the inner peripheral surfaces of the second short circuit through holes 22, the front end face 22b located at the front end of the flow direction F2 and facing the back of the flow direction F2 is also from the outside in the radial direction It gradually extends toward the front side of the flow direction F2 as it goes. The rear end face 22a and the front end face 22b of the second short circuit through hole 22 are substantially parallel.

As shown in FIG. 4, in the orifice passage, a third shorted through hole 23 is short-circuited and opened on the side of the connecting portion with the other liquid chamber 14 b on the wall surface defining the connecting portion with the one liquid chamber 14 a. And, on the wall surface defining the connecting portion with the other liquid chamber 14b, a fourth short circuit through hole 24 which is opened by shorting to the connecting portion side with the one liquid chamber 14a is formed.

The flow resistances of the third short circuit through hole 23 and the fourth short circuit through hole 24 are smaller than the flow resistance of the orifice passage and smaller than the flow resistances of the first short circuit through hole 21 and the second short through hole 22. The flow passage cross-sectional area of each of the third short circuit through hole 23 and the fourth short circuit through hole 24 is, for example, about 3 mm ² or more, and the flow passage cross sectional area of the orifice passage and the first communication opening 18 and the second communication It is smaller than each opening area of the opening 20. Each length of the third short circuit through hole 23 and the fourth short circuit through hole 24 is shorter than the length of the orifice passage.
The flow resistances of the third short circuit through hole 23 and the fourth short circuit through hole 24 may be equal to or higher than the flow resistances of the first short circuit through hole 21 and the second short circuit through hole 22.

The third short circuit through hole 23 and the fourth short circuit through hole 24 define one end in the circumferential direction of the first groove 19a and are formed in the end wall 19c extending in the axial direction, and extend in the circumferential direction . The third short circuit through hole 23 and the fourth short circuit through hole 24 are formed on the outer peripheral surface facing the outer side in the radial direction among the surfaces of the end wall 19 c and penetrate the end wall 19 c in the circumferential direction. The third short circuit through hole 23 and the fourth short circuit through hole 24 linearly extend in the direction orthogonal to the axial direction in a front view as viewed from the outer side in the radial direction.

The third short circuit through hole 23 opens in the orifice passage in the direction opposite to the flow direction F1 in which the liquid circulates from one liquid chamber 14a to the other liquid chamber 14b in the orifice passage, and the fourth short circuit through hole 24 is the orifice passage The liquid is opened in the opposite direction of the flow direction F2 in which the liquid circulates from the other liquid chamber 14b to the one liquid chamber 14a. The third short circuit through hole 23 and the fourth short circuit through hole 24 are open toward one circumferential end of the second groove 19 b in the other covering member 17.

The third short circuit through hole 23 and the fourth short circuit through hole 24 are formed at the axial center portion of the end wall 19 c. The third short circuit through hole 23 is circumferentially adjacent to the axial center of the first communication opening 18, and the fourth short circuit through hole 24 is circumferentially close to the axial central portion of the second communication opening 20. doing.
The covering member 17 which is the same as the covering member 17 in which the third short circuit through hole 23 and the fourth short circuit through hole 24 are formed as the third short circuit through hole 23 and the fourth short circuit through hole 24 is formed. The second groove 19b may be opened. Further, as the third short circuit through hole 23 and the fourth short circuit through hole 24, in the orifice passage, the connection portion with one liquid chamber 14a and the connection portion with the other liquid chamber 14b are short circuited and directly connected. A configuration may be adopted.

As shown in FIGS. 3, 6 and 7, the medium elastic body 32 is elastically deformed by the internal pressure of the

liquid chambers

14 a and 14 b so that the

liquid chambers

14 a and 14 b communicate with each other and the liquid Groove-

like leak passages

27, 28 are formed to flow between the

chambers

14a, 14b. In the standby state before the internal pressure of each of the

liquid chambers

14a and 14b changes, the

leak paths

27 and 28 are elastically deformed due to the covering member 17 elastically deforming the partition walls of the

leak paths

27 and 28. The communication between the

liquid chambers

14a and 14b through 28 is blocked.
The

leak passages

27, 28 are formed in the middle elastic body 32 on the outer surface in contact with the inner surface of the covering member 17. The

leak passages

27 and 28 are open at the side surface of the middle elastic body 32 facing in the circumferential direction. The

leak passages

27, 28 extend linearly in the direction orthogonal to the axial direction in a front view when the outer surface of the middle elastic body 32 is viewed from the outer side in the radial direction.

A plurality of

leak passages

27, 28 are formed in the middle elastic body 32 at different axial positions. In the illustrated example, the leak passages 27 are formed one by one in the main portion 32 a and the pair of sub portions 32 b in the middle elastic body 32.
Of the plurality of

leak passages

27, 28, the first leak passage 27 formed in the main portion 32a is disposed at the axial center of the main portion 32a, and in the second leak passage 28 formed in the sub portion 32b. The axial center portion is located axially outside of the axial center portion of the sub portion 32b. At least two of the plurality of

leak passages

27, 28 have different channel lengths. In the illustrated example, the circumferential length of the first leak passage 27 is longer than the circumferential length of the second leak passage 28. The width of the first leak passage 27 is narrower than the width of the second leak passage 28.

At least two of the plurality of

leak passages

27, 28 have different amounts of elastic deformation of the partition wall of the

leak passages

27, 28 by the covering member 17. In the present embodiment, the amount of elastic deformation by the covering member 17 of the partition wall of the first leak passage 27 is larger than the amount of elastic deformation by the covering member 17 of the partition wall of the second leak passage 28. The internal pressure of the

fluid chambers

14a and 14b in which the first leak passage 27 opens is higher than the internal pressure of the

fluid chambers

14a and 14b in which the second leak passage 28 opens.
The amount of elastic deformation by the covering member 17 of the partition wall of the first leak passage 27 may be smaller than the amount of elastic deformation by the covering member 17 of the partition wall of the second leak passage 28. Further, the internal pressure of the

liquid chambers

14a and 14b in which the first leak passage 27 is opened may be equal to or less than the internal pressure of the

liquid chambers

14a and 14b in which the second leak passage 28 is opened.

On the inner surface of the covering member 17, protruding ribs 17 a inserted separately in the first leak passage 27 and the second leak passage 28 are formed. A plurality of projecting ribs 17a are formed on the inner surface of the covering member 17 at respective positions sandwiching the central axis O in the radial direction at intervals in the axial direction, and each projecting rib 17a is formed in the first leak passage 27 and It is separately inserted into the second leak passage 28. The projecting ribs 17 a are disposed in the first leak passage 27 and the second leak passage 28 along the entire circumferential length. The projecting rib 17 a abuts on the entire inner surfaces of the first leak passage 27 and the second leak passage 28.

The respective end portions in the circumferential direction of the plurality of projecting ribs 17a arranged at intervals in the axial direction are integrally connected in the axial direction by the press-contacting protrusions 17f extending in the axial direction. The protruding ribs 17 a are formed on both end portions in the circumferential direction on the inner surface of one covering member 17. One projecting rib 17a is divided in the circumferential direction at the peripheral edge of the covering member 17, and the two covering members 17 are combined in the circumferential direction.
The first short circuit through hole 21, the second short circuit through hole 22, the third short circuit through hole 23, and the fourth short circuit through hole 24 are axially outward of the first leak passage 27 and the second leak passage 28. It is located more inside in the axial direction.

As described above, according to the vibration damping device 1 of the present embodiment, the short circuit through holes (the first short circuit through hole 21, the second short circuit through hole 22, the third short circuit through hole 23, the fourth short circuit through hole 21) A short circuit through hole 24) is formed. More specifically, the liquid flowing in the orifice passage from one liquid chamber 14a to the other liquid chamber 14b is short-circuited in the other liquid chamber 14b on the wall surface defining the orifice passage. Since the first short circuit through hole 21 to be formed is formed, even if large vibrational energy is input, the liquid flowing in the orifice passage from one liquid chamber 14a toward the other liquid chamber 14b is the other liquid chamber It becomes possible to short-circuit and reach the inside of 14b, and it can suppress that the internal pressure of one liquid chamber 14a becomes high too much. Thereby, even if a high viscosity liquid having a kinematic viscosity of 50 cSt or more at 40 ° C. is sealed in the

liquid chambers

14a and 14b, it is possible to suppress, for example, an increase in dynamic spring constant and liquid leakage.

Further, in the present embodiment, since the second short circuit through hole 22 is formed in the wall surface defining the orifice passage, even if large vibrational energy is input, the inside of the orifice passage is separated from the other liquid chamber 14b. The liquid flowing toward the liquid chamber 14a can be short-circuited and reached in one of the liquid chambers 14a, and the internal pressure of the other liquid chamber 14b can be suppressed from being excessively high. Thereby, even if a high viscosity liquid having a kinematic viscosity of 50 cSt or more at 40 ° C. is sealed in the

liquid chambers

14a and 14b, it is possible to suppress, for example, an increase in dynamic spring constant and liquid leakage.
In addition, since the high viscosity liquid is enclosed in the

liquid chambers

14a and 14b, the peak of the attenuation characteristic based on liquid column resonance in the orifice passage is spread over a wide frequency range, and the attenuation performance is exhibited in a wide frequency range. Can.

Further, since the first short circuit through hole 21 is opened at the rear end of the other fluid chamber 14b in the flow direction F1, when the internal pressure of the one fluid chamber 14a exceeds a predetermined value, the orifice The liquid flowing in the passage from one liquid chamber 14a to the other liquid chamber 14b can be short circuited and reach the other liquid chamber 14b immediately.
Further, in the present embodiment, since the second short circuit through hole 22 is opened at the end on the rear side of the flow direction F2 in one liquid chamber 14a, the internal pressure of the other liquid chamber 14b exceeds a predetermined value. At this time, the fluid flowing from the other fluid chamber 14b to the one fluid chamber 14a in the orifice passage can be short circuited immediately and reach the one fluid chamber 14a.

Further, since the rear end face 21a of the first short circuit through hole 21 extends gradually toward the front side of the flow direction F1 from the outer side in the radial direction toward the inner side, the inside of the orifice passage is extended from one liquid chamber 14a to the other The liquid flowing toward the liquid chamber 14b and reaching the first short circuit through hole 21 can be smoothly introduced into the other liquid chamber 14b through the first short circuit through hole 21 without causing backflow or the like.
Further, since the rear end face 22a of the second short circuit through hole 22 gradually extends toward the front side of the flow direction F2 as it goes from the outer side to the inner side in the radial direction, one in the orifice passage from the other liquid chamber 14b The liquid flowing toward the liquid chamber 14 a and reaching the second short circuit through hole 22 can be smoothly introduced into the one liquid chamber 14 a through the second short circuit through hole 22 without causing backflow or the like.

Further, according to the vibration control device 1 according to the present embodiment, the orifice passage is short-circuited and opened on the wall surface defining the connection portion with one liquid chamber 14a on the connection portion side with the other liquid chamber 14b. Since the third short circuit through hole 23 is formed, the liquid flowing from the one liquid chamber 14a into the orifice passage flows not only in the flow toward the other liquid chamber 14b passing through the orifice passage, but also the third short circuit through hole A flow can also be generated towards the side of the orifice passage through the hole 23 in the connection with the other fluid chamber 14b. As a result, even if large vibrational energy is input, the liquid flowing into the orifice passage from one of the liquid chambers 14a is branched to reach the other liquid chamber 14b through the two paths, and the flow resistance of the liquid As a result, it is possible to reduce the internal pressure of one fluid chamber 14a from becoming excessively high. Therefore, even if a highly viscous liquid having a kinematic viscosity of 50 cSt or more at 40 ° C. is sealed in the

liquid chambers

14a and 14b, for example, the rise of the dynamic spring and the leakage of the liquid can be suppressed.

Further, in the present embodiment, in the orifice passage, the fourth short circuit through hole 24 which is shorted and opened on the connection portion side with the one liquid chamber 14a is formed on the wall surface defining the connection portion with the other liquid chamber 14b. Since it is formed, the fluid flowing from the other fluid chamber 14b into the orifice passage is not only the flow passing through the orifice passage toward the one fluid chamber 14a, but also the orifice passage through the fourth short through hole 24. It is possible to generate a flow toward the connecting portion side with one of the liquid chambers 14a in the above, and it is also possible to suppress an excessively high internal pressure of the other liquid chamber 14b. Therefore, even if a highly viscous liquid having a kinematic viscosity of 50 cSt or more at 40 ° C. is sealed in the

liquid chambers

Further, since the third short circuit through hole 23 and the fourth short circuit through hole 24 are opened in the opposite direction of the flow directions F1 and F2, respectively, the liquid flowing from the

liquid chambers

14a and 14b into the orifice passage is smoothed. Can be branched into two paths.
Further, the orifice passage is extended between the covering member 17 and the outer cylinder 12 in the circumferential direction for one and a half more or more, and the flow passage length is secured long, so the viscosity of the liquid is excessively high. Without it, it is possible to generate a high damping force, and the liquid can be easily injected into the

liquid chambers

14a and 14b.

The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the present invention.

For example, in the embodiment described above, the groove portion extending in the axial direction is shown as the recess portion 16a, but the groove portion extending in the circumferential direction is not limited to this, for example, a groove shape extending in the circumferential direction You may change suitably, such as adopting a form.
In addition, the stopper portion 16 may not bulge from the outer peripheral surface of the inner mounting member 11 toward the outer side in the radial direction.
Alternatively, the axial end of the recess 16 a may be open at the end surface 15 b of the stopper 16.
Further, the recess 16a may not be formed on the outer peripheral surface of the inner mounting member 11, and the outer diameter of the stopper elastic portion 34 may be equal over the entire circumference.

Further, it is not necessary to form the first divided portion 34c and the second divided portion 34d in the stopper elastic portion 34, and as the first divided portion 34c, slits in which the inner portion 34a and the outer portion 34b contact each other in the circumferential direction You may employ | adopt as a 2nd division part 34d, you may employ | adopt the slit which the stopper elastic part 34 and the end elastic body 31 mutually mutually contact | abut in an axial direction.
In the longitudinal sectional view, the corresponding portion of the outer surface of the stopper elastic portion 34 and the opposed portion of the inner surface of the covering member 17 axially extend over the entire area, but, for example, the corresponding portion and Any one of the facing portions may be changed as appropriate, such as extending in the axial direction while waving in the radial direction.

Further, the second short circuit through hole 22, the third short circuit through hole 23, and the fourth short circuit through hole 24 may not be formed in the covering member 17. Alternatively, the first short circuit through hole 21, the second short circuit through hole 22, and the fourth short circuit through hole 24 may not be formed in the covering member 17. The positions where the first short circuit through hole 21, the second short circuit through hole 22, the third short circuit through hole 23, and the fourth short circuit through hole 24 are formed in the main body groove 19 are not limited to the above embodiment, but may be appropriately changed. Good. The inner peripheral surfaces of the first short circuit through hole 21 and the second short circuit through hole 22 may be appropriately changed, for example, by extending in the radial direction.
In addition, as the orifice passage, a configuration may be adopted which extends one or less round in the circumferential direction.
Further, although the configuration in which the main body groove 19 is formed on the outer peripheral surface of the covering member 17 is shown, the main body groove 19 may be formed on the inner peripheral surface of the outer cylinder 12.

In addition, a reinforcing body may be embedded in the middle elastic body 32. Further, the medium elastic body 32 may not be compressed and deformed by the covering member 17. Alternatively, the covering member 17 may be fitted between the middle elastic bodies 32 adjacent to each other in the circumferential direction, and the middle elastic body 32 may be exposed from between the covering members 17 adjacent to each other in the circumferential direction.
Further, the plurality of

leak passages

27 and 28 may not be formed in the middle elastic body 32.
In addition, although the configuration including the main portion 32 a and the sub portion 32 b is shown as the middle elastic body 32, for example, a configuration including only one of the main portion 32 a and the sub portion 32 b may be adopted It is also good.

According to the present invention, since the short circuit through hole is formed in the wall surface defining the orifice passage, even if large vibration energy is input, the inside of the orifice passage is directed from one liquid chamber to the other liquid chamber It is possible to short-circuit the flowing liquid in the other liquid chamber and reach it, and it is possible to suppress the internal pressure of one liquid chamber from becoming excessively high. Thereby, even if a high viscosity liquid having a kinematic viscosity of 50 cSt or more at 40 ° C. is sealed in the liquid chamber, it is possible to suppress, for example, an increase in dynamic spring constant, leakage of the liquid, and the like.
In addition, since the high viscosity liquid is sealed in the liquid chamber, the peak of the attenuation characteristic based on liquid column resonance in the orifice passage spreads over a wide frequency range, and the attenuation performance can be exhibited in a wide frequency range.

Here, in the other fluid chamber, the short circuit through hole opens at the rear end of the flow direction in which the fluid flows from the one fluid chamber to the other fluid chamber in the orifice passage. May be

In this case, since the short circuit through hole opens at the rear end of the other fluid chamber in the flow direction, when the internal pressure of one fluid chamber exceeds a predetermined value, one of the orifice passages is The liquid flowing from the liquid chamber to the other liquid chamber can be immediately short-circuited to reach the other liquid chamber.

Further, the short circuit through hole is formed on the outer peripheral surface of the covering member, and in the inner peripheral surface of the short circuit through hole, it flows in the orifice passage from the one liquid chamber to the other liquid chamber The rear end surface located at the rear end of the flow direction and facing the front side in the flow direction may gradually extend toward the front side in the flow direction as it goes from the outer side to the inner side in the radial direction.

In this case, since the rear end surface of the short circuit through hole gradually extends toward the front side in the flow direction as it goes from the outer side to the inner side in the radial direction, the inside of the orifice passage is directed from one liquid chamber to the other The liquid that has circulated and reached the short circuit through hole can be smoothly introduced into the other liquid chamber through the short circuit through hole without reverse flow or the like.

According to the present invention, in the orifice passage, the wall surface defining the connection portion with one of the liquid chambers is formed with the short circuit through hole which is opened by shorting to the connection portion with the other liquid chamber. Therefore, not only the flow from the one fluid chamber into the orifice passage toward the other fluid chamber through the orifice passage, but also the connecting portion with the other fluid chamber in the orifice passage through the short-circuited through hole A flow towards the side can also occur. As a result, even if large vibrational energy is input, the liquid that has flowed into the orifice passage from one of the liquid chambers diverges and reaches the other liquid chamber through the two paths. Therefore, it is possible to reduce the flow resistance of the liquid, and it is possible to suppress the internal pressure of one liquid chamber from becoming excessively high. Therefore, even if a liquid having a high viscosity of 50 cSt or higher at 40 ° C. is sealed in the liquid chamber, it is possible to suppress, for example, an increase in dynamic spring constant, leakage of the liquid, and the like.
Since the high viscosity liquid is enclosed in the liquid chamber, the peak of the attenuation characteristic based on the liquid column resonance in the orifice passage spreads over a wide frequency range. Therefore, attenuation performance can be exhibited in a wide frequency range.

Here, the orifice passage is extended between the covering member and the outer cylinder over one and a half circumferences in the circumferential direction, and in the short-circuit through hole, the liquid in the orifice passage is the one liquid chamber It may be opened in the opposite direction of the flow direction flowing from the second liquid chamber to the other liquid chamber.

In this case, since the short circuit through hole opens in the opposite direction to the flow direction, the liquid flowing from the one liquid chamber into the orifice passage can be smoothly branched into two paths.
The orifice passage is extended between the covering member and the outer cylinder over one and a half circumferences in the circumferential direction, and a long flow path length is secured. Therefore, high damping force can be generated without excessively increasing the viscosity of the liquid, and the liquid can be easily injected into the liquid chamber.

In addition, it is possible to replace the component in the above-mentioned embodiment with a well-known component suitably, in the range which does not deviate from the meaning of the present invention, and may combine the above-mentioned modification suitably.

DESCRIPTION OF SYMBOLS 1 Anti-vibration device 11 Inner mounting member 12

Outer cylinder

14a, 14b Liquid chamber 17 Coating member 21 1st short circuit through

hole

21a, 22a Rear end face 22 2nd short circuit through hole 23 3rd short circuit through hole 24 4th short circuit through hole 31 end Elastic body (elastic body)
32 Medium elastic body (elastic body)
F1, F2 distribution direction O central axis

Claims

An inner mounting member connected to any one of the vibration generating unit and the vibration receiving unit;
An outer cylinder connected to any one of the vibration generating unit and the vibration receiving unit and surrounding the inner mounting member;
An elastic body that elastically connects the inner attachment member and the outer cylinder,
The elastic body includes middle elastic bodies separately disposed on both sides of the inner mounting member in a radial direction intersecting the central axis in a plan view as viewed in the axial direction along the central axis of the outer cylinder. ,
Between the inner attachment member and the outer cylinder, the inner attachment member covers between the middle elastic bodies adjacent to each other in the circumferential direction around the central axis in the plan view and from the outer side in the radial direction A covering member defining two fluid chambers between the
An orifice passage communicating the two liquid chambers with each other is formed between the covering member and the outer cylinder.
A liquid having a kinematic viscosity of 50 cSt or higher at 40 ° C. is enclosed in the two liquid chambers,
The vibration control device in which the short circuit through hole is formed in the wall surface of the said orifice channel | path.
The two short-circuited through holes are formed in the wall surface defining the orifice passage, and the two fluids flowing in the orifice passage from one of the two fluid chambers toward the other of the two fluid chambers are A short circuit to the other end of the fluid chamber
The antivibration device according to claim 1, wherein a flow resistance of the short circuit through hole is smaller than a flow resistance of the orifice passage.
In the other of the two liquid chambers, the short circuit through hole is an end on the rear side of the flow direction in which the liquid circulates in the orifice passage from one of the two liquid chambers toward the other of the two liquid chambers. The vibration control device according to claim 2, wherein
The short circuit through hole is formed on the outer peripheral surface of the covering member,
It is located at the end on the rear side in the flow direction in which the inside of the orifice passage flows from one of the two liquid chambers toward the other of the two liquid chambers, of the inner peripheral surface of the short circuit through hole, The anti-vibration device according to claim 2, wherein the rear end surface facing the front side in the direction gradually extends toward the front side in the flow direction as going from the outer side to the inner side in the radial direction.
The short circuit through hole is formed on the outer peripheral surface of the covering member,
It is located at the end on the rear side in the flow direction in which the inside of the orifice passage flows from one of the two liquid chambers toward the other of the two liquid chambers, of the inner peripheral surface of the short circuit through hole, The anti-vibration device according to claim 3, wherein the rear end surface facing the front side in the direction gradually extends toward the front side in the flow direction as going from the outer side to the inner side in the radial direction.
The short circuit through hole opens in the wall surface defining the connection portion with one of the two liquid chambers in the orifice passage, and opens in a short circuit toward the connection portion with the other of the two liquid chambers,
The antivibration device according to claim 1, wherein a flow resistance of the short circuit through hole is smaller than a flow resistance of the orifice passage.
The orifice passage is extended between the covering member and the outer cylinder along the circumferential direction for one and a half or more.
The short circuit through hole opens in the orifice passage in a direction opposite to a flow direction in which the liquid flows from one of the two liquid chambers toward the other of the two liquid chambers. The vibration control device according to 6.