JP6853674B2 - Anti-vibration device - Google Patents

Description

The present invention relates to a vibration isolator that is applied to, for example, automobiles, industrial machines, etc., and absorbs and attenuates vibrations of vibration generating parts such as engines.

Conventionally, as this kind of vibration isolation device, a tubular first mounting member connected to one of a vibration generating portion and a vibration receiving portion, a second mounting member connected to the other, and both mountings thereof. A configuration is known to include an elastic body for connecting the members and a partition member for partitioning the liquid chamber in the first mounting member in which the liquid is sealed into a main liquid chamber and a sub liquid chamber. The partition member is formed with a restricted passage that connects the main liquid chamber and the sub liquid chamber. In this vibration isolation device, when vibration is input, both mounting members are relatively displaced while elastically deforming the elastic body, and the hydraulic pressure in the main liquid chamber is fluctuated to allow the liquid to flow through the limiting passage to absorb the vibration. And decaying.

By the way, in this vibration isolator, for example, a large load (vibration) is input due to unevenness of the road surface, the hydraulic pressure in the main liquid chamber rises sharply, and then the load is input in the opposite direction due to the rebound of the elastic body or the like. Occasionally, the main fluid chamber may suddenly become negatively pressurized. Then, this rapid negative pressure causes cavitation in which a large number of bubbles are generated in the liquid, and further, abnormal noise may be generated due to cavitation collapse in which the generated bubbles collapse.
Therefore, for example, by providing a valve body in the restricted passage as in the vibration isolator shown in Patent Document 1 below, even when a vibration having a large amplitude is input, the main liquid chamber is made negative pressure. The structure to suppress is known.

Japanese Unexamined Patent Publication No. 2012-172832

However, in the conventional anti-vibration device, since the valve body is provided, the structure becomes complicated and the valve body needs to be tuned, so that there is a problem that the manufacturing cost increases. Further, by providing the valve body, the degree of freedom in design is lowered, and as a result, the vibration isolation characteristics may be lowered.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an anti-vibration device capable of suppressing the generation of abnormal noise due to cavitation collapse without deteriorating the anti-vibration characteristics with a simple structure. To do.

In order to solve the above problems, the present invention proposes the following means.
The vibration isolator according to the present invention includes a tubular first mounting member connected to either one of a vibration generating portion and a vibration receiving portion, a second mounting member connected to the other, and both mounting members. The partition member is provided with an elastic body for elastically connecting the two, and a partition member for partitioning the liquid chamber in the first mounting member in which the liquid is sealed into the first liquid chamber and the second liquid chamber. , A liquid-filled type anti-vibration device in which a limiting passage for communicating the first liquid chamber and the second liquid chamber is formed, and the limiting passage is a first communication portion that opens into the first liquid chamber. A pair of main body flow paths that communicate with the first communication part and the second communication part, and a pair of inner surfaces of the main body flow paths facing each other. A plurality of protrusions protruding in opposite directions facing each other are provided on the facing surface along the flow path direction of the main body flow path, and the protrusions are provided in a row in the flow path direction, and the protrusions have three corner portions. Two of them have a triangular shape located on the facing surface, and the protrusions provided on one facing surface and the protrusions on the other facing surface that are adjacent to each other in the flow path direction are adjacent to each other. The portion located between the two faces each other in the facing direction, and the distance between the pair of facing surfaces is larger than twice the protruding height of the protrusion from the facing surfaces. It is a feature.
The triangular apex angle exhibited by the protrusion may be an obtuse angle.
The plurality of protrusions may have the same shape as each other. The plurality of protrusions may have the same size as each other.

According to the present invention, at the time of vibration input, both mounting members are relatively displaced while elastically deforming the elastic body, the hydraulic pressures of the first liquid chamber and the second liquid chamber fluctuate, and the liquid passes through the limiting passage. Attempts to circulate between the first and second liquid chambers. At this time, the liquid flows into the restricted passage through one of the first communication portion and the second communication portion, passes through the main body flow path, and then passes through the other of the first communication portion and the second communication portion. Outflow from.
Here, when a large load (vibration) is input to the vibration isolator, the liquid flows through the main body flow path while colliding with the protrusions provided on the pair of facing surfaces, so that the liquid collides with the protrusions. This causes energy loss and energy loss due to friction between the liquid and the protrusion, which makes it possible to increase the pressure loss of the liquid flowing through the restricted passage, and the first communication part and the second communication part can be increased. The flow velocity of the liquid passing through can be reduced. As a result, between the liquid that has passed through one of the first communication portion and the second communication portion and has flowed into the first liquid chamber or the second liquid chamber and the liquid in the first liquid chamber or the second liquid chamber. The difference in flow velocity generated in the above can be suppressed to a small value, and the generation of vortices due to the difference in flow velocity and the generation of bubbles due to this vortex can be suppressed.
Further, since the distance between the pair of facing surfaces in the main body flow path is larger than twice the height of the protrusion from the facing surface, the flow does not interfere with the protrusion in the main body flow path. An area extending in the road direction will be secured. Therefore, when a normal load is input to the anti-vibration device, it is possible to make it difficult for the above-mentioned pressure loss to occur, and it is possible to stably exhibit the desired anti-vibration characteristics.

Here, at least one of the first communication portion and the second communication portion is opened in the first liquid chamber or the second liquid chamber in a direction orthogonal to the flow path direction and the opposite direction. May be good.

In this case, the liquid flowing along the protrusion in the main body flow path is bent at a right angle, and the first liquid chamber or the second liquid chamber or the second liquid chamber or the second from one of the first communication portion and the second communication portion. It will flow into the liquid chamber. Therefore, even if a large load is input to the vibration isolator, the flow velocity of the liquid flowing into the first liquid chamber or the second liquid chamber can be surely reduced.

Further, at least one of the first communication portion and the second communication portion may be provided with a plurality of pores penetrating the barrier facing the first liquid chamber or the second liquid chamber.

In this case, when the liquid flows into the first liquid chamber or the second liquid chamber through the plurality of pores provided in one of the first communication portion and the second communication portion, these pores are formed. Since each pore is circulated while being pressure-lossed by the barrier, the flow velocity of the liquid flowing into the first liquid chamber or the second liquid chamber can be suppressed. Moreover, since the liquid flows through a plurality of pores instead of a single pore, the liquid can be branched and circulated in a plurality of pores, and the flow velocity of the liquid passing through the individual pores can be reduced. Can be done. Further, even if bubbles are generated in the restricted passage, since a plurality of pores are arranged, the generated bubbles can be separated from each other in the first liquid chamber or the second liquid chamber, and the bubbles merge. It is possible to suppress the growth and make it easier to maintain the state in which the bubbles are finely dispersed.

Further, at least one of the first communication portion and the second communication portion is in the flow path direction from a portion of the main body flow path in which a plurality of protrusions are arranged along the flow path direction. It may be opened in a distant part.

In this case, when a large load is input to the vibration isolator, the flow velocity of the liquid may be reduced by the plurality of protrusions as described above, and then the liquid may flow into the first liquid chamber or the second liquid chamber. it can. Therefore, even if a large load is input to the vibration isolator, the flow velocity of the liquid flowing into the first liquid chamber or the second liquid chamber can be reduced more reliably.

According to the present invention, it is possible to suppress the generation of abnormal noise due to cavitation collapse without deteriorating the anti-vibration characteristics with a simple structure.

It is a vertical sectional view of the vibration isolation device which concerns on one Embodiment of this invention. It is a top view of the partition member constituting the vibration isolation device shown in FIG.

Hereinafter, embodiments of the vibration isolator according to the present invention will be described with reference to FIGS. 1 and 2.
As shown in FIG. 1, the vibration isolator 10 is attached to a tubular first mounting member 11 connected to either one of the vibration generating portion and the vibration receiving portion and to either one of the vibration generating portion and the vibration receiving portion. The second mounting member 12 to be connected, the elastic body 13 elastically connecting the first mounting member 11 and the second mounting member 12 to each other, and the main liquid chamber (first liquid chamber) described later in the first mounting member 11. ) 14, A liquid-filled type anti-vibration device including a partition member 16 for partitioning into a secondary liquid chamber (second liquid chamber) 15.

Hereinafter, the direction along the central axis O of the first mounting member 11 is referred to as an axial direction. Further, the second mounting member 12 side along the axial direction is referred to as an upper side, and the partition member 16 side is referred to as a lower side. Further, in a plan view of the vibration isolator 10 from the axial direction, the direction orthogonal to the central axis O is referred to as the radial direction, and the direction orbiting around the central axis O is referred to as the circumferential direction.
The first mounting member 11, the second mounting member 12, and the elastic body 13 are each formed in a circular shape or an annular shape in a plan view, and are arranged coaxially with the central axis O.

When the vibration isolator 10 is mounted on an automobile, for example, the second mounting member 12 is connected to the engine as a vibration generating portion, and the first mounting member 11 is connected to the vehicle body as a vibration receiving portion. As a result, the vibration of the engine is suppressed from being transmitted to the vehicle body.

The second mounting member 12 is a columnar member extending in the axial direction, and is formed in a hemispherical shape in which the lower end portion bulges downward, and the flange portion 12a is formed above the hemispherical lower end portion. have. A screw hole 12b extending downward from the upper end surface of the second mounting member 12 is bored, and a bolt (not shown) serving as a mounting tool on the engine side is screwed into the screw hole 12b. The second mounting member 12 is arranged at the upper end opening of the first mounting member 11 via the elastic body 13.

The elastic body 13 is a rubber body that is vulcanized and adhered to the upper end opening of the first mounting member 11 and the outer peripheral surface of the lower portion of the second mounting member 12, respectively, and is interposed between them. The upper end opening of the mounting member 11 is closed from above. The upper end of the elastic body 13 comes into contact with the flange portion 12a of the second mounting member 12, so that the elastic body 13 is sufficiently adhered to the second mounting member 12 and follows the displacement of the second mounting member 12 satisfactorily. ing. A rubber film 17 that tightly covers the inner peripheral surface of the first mounting member 11 and the inner peripheral portion of the lower end opening edge is integrally formed at the lower end portion of the elastic body 13. As the elastic body 13, an elastic body made of synthetic resin or the like can be used in addition to rubber.

The first mounting member 11 is formed in a cylindrical shape having a flange 18 at the lower end portion, and is connected to a vehicle body or the like as a vibration receiving portion via the flange 18. The portion of the inside of the first mounting member 11 located below the elastic body 13 is the liquid chamber 19. In the present embodiment, the partition member 16 is provided at the lower end of the first mounting member 11, and the diaphragm 20 is further provided below the partition member 16. The upper surface of the outer peripheral portion 22 of the partition member 16 is in contact with the lower end opening edge of the first mounting member 11.

The diaphragm 20 is made of an elastic material such as rubber or a soft resin, and is formed in a bottomed cylindrical shape. The upper end of the diaphragm 20 is axially sandwiched by the lower surface of the outer peripheral portion 22 of the partition member 16 and the ring-shaped holder 21 located below the partition member 16. The lower end of the rubber film 17 is in liquidtight contact with the upper surface of the outer peripheral portion 22 of the partition member 16.

Under such a configuration, the outer peripheral portion 22 of the partition member 16 and the holder 21 are arranged in this order downward on the lower end opening edge of the first mounting member 11, and are integrally fixed by screws 23. As a result, the diaphragm 20 is attached to the lower end opening of the first attachment member 11 via the partition member 16. In the illustrated example, the bottom portion of the diaphragm 20 has a shape deep on the outer peripheral side and shallow in the central portion. However, as the shape of the diaphragm 20, in addition to such a shape, various conventionally known shapes can be adopted.

Then, as the diaphragm 20 is attached to the first attachment member 11 via the partition member 16 in this way, the liquid chamber 19 is formed in the first attachment member 11 as described above. The liquid chamber 19 is arranged inside the first mounting member 11, that is, inside the first mounting member 11 in a plan view, and is a closed space sealed by the elastic body 13 and the diaphragm 20 in a liquid-tight manner. .. Then, the liquid L is sealed (filled) in the liquid chamber 19.

The liquid chamber 19 is divided into a main liquid chamber 14 and a sub liquid chamber 15 by a partition member 16. The main liquid chamber 14 is formed by forming the lower surface 13a of the elastic body 13 as a part of the wall surface, and the rubber film 17 and the partition member 16 that tightly cover the inner peripheral surfaces of the elastic body 13 and the first mounting member 11 It is a space surrounded by and, and the internal volume changes due to the deformation of the elastic body 13. The auxiliary liquid chamber 15 is a space surrounded by the diaphragm 20 and the partition member 16, and the internal volume changes due to the deformation of the diaphragm 20. The vibration isolator 10 having such a configuration is a compression type device used by attaching the main liquid chamber 14 so as to be located on the upper side in the vertical direction and the sub liquid chamber 15 to be located on the lower side in the vertical direction. ..

The partition member 16 is provided with a restriction passage 24 that communicates the main liquid chamber 14 and the sub liquid chamber 15. As shown in FIG. 2, the limiting passage 24 includes a main body flow path 25 arranged in the partition member 16, a first communication portion 26 for communicating the main body flow path 25 and the main liquid chamber 14, and a main body flow path. A second communication portion 27 that communicates the 25 and the auxiliary liquid chamber 15 is provided.

The main body flow path 25 extends in the partition member 16 along the circumferential direction, and the flow path direction and the circumferential direction of the main body flow path 25 are in the same direction. The main body flow path 25 may extend in a direction intersecting the circumferential direction. The main body flow path 25 is formed in an arc shape coaxially arranged with the central axis O, and extends along the circumferential direction over substantially the entire circumference of the partition member 16. The main body flow path 25 is defined by a first barrier 28 facing the main liquid chamber 14 and a second barrier 29 facing the sub liquid chamber 15 among the partition members 16. Both the first barrier 28 and the second barrier 29 are formed in a plate shape with the front and back surfaces facing in the axial direction. The first barrier 28 is axially sandwiched between the main body flow path 25 and the main liquid chamber 14, and is located between the main body flow path 25 and the main liquid chamber 14. The second barrier 29 is axially sandwiched between the main body flow path 25 and the auxiliary liquid chamber 15, and is located between the main body flow path 25 and the auxiliary liquid chamber 15.

The second communication portion 27 includes one opening 32 that penetrates the second barrier 29 in the axial direction. The opening 32 is arranged in a portion of the second barrier 29 that forms one end along the circumferential direction of the main body flow path 25.
The first communication portion 26 includes a plurality of pores 31 that penetrate the first barrier 28 in the axial direction and are arranged along the circumferential direction (the flow path direction of the main body flow path 25). The plurality of pores 31 are arranged in a portion of the first barrier 28 that forms the other end along the circumferential direction of the main body flow path 25. At least a part of the plurality of pores 31 forms a row of holes arranged at intervals in the circumferential direction on a concentric circle centered on the central axis O.
Hereinafter, the one end side of the main body flow path 25 is referred to as one side, and the other end side is referred to as the other side along the circumferential direction.

Each of the plurality of pores 31 is smaller than the flow path cross-sectional area of the main body flow path 25, and is arranged inside each of the first barrier 28 and the main body flow path 25 in a plan view. In the illustrated example, the lengths of the plurality of pores 31 are equal to each other. The inner diameters of the plurality of pores 31 are equal to each other. The lengths and inner diameters of the plurality of pores 31 may be different from each other.
A plurality of pores 31 are formed in the first barrier 28 at intervals in the radial direction. That is, a plurality of the holes are arranged on the first barrier 28 at intervals in the radial direction. In the illustrated example, two pores 31 are formed in the first barrier 28 at intervals in the radial direction. The pores 31 adjacent to each other in the radial direction are arranged so that their positions in the circumferential direction are offset from each other. The plurality of pores 31 may be arranged in the first barrier 28 at equivalent positions along the circumferential direction with a radial interval.

Each of the plurality of pores 31 is gradually reduced in diameter from the main body flow path 25 side toward the main liquid chamber 14 side along the axial direction, that is, from the inner side to the outer side in the axial direction, and the taper angle is, for example, about 30. It is formed in a truncated cone shape, and in all the pores 31, the open end (hereinafter, referred to as “open end”) on the main liquid chamber 14 side is the minimum inner diameter and the cross-sectional area of the flow path. The opening area of the opening end of the pore 31 may be, for example, 25 mm ² or less, preferably 2 mm ² or more and 8 mm ² or less.
The total flow path cross-sectional area of the entire first communication portion 26, which is the sum of the opening areas at the opening ends of the plurality of pores 31 for all of the plurality of pores 31, is the minimum value of the flow path cross-sectional area in the main body flow path 25. For example, it may be 1.8 times or more and 4.0 times or less.

In the present embodiment, a plurality of protrusions 34 protruding in opposite directions are provided on the pair of facing surfaces 25a facing each other in the inner surface of the main body flow path 25 along the circumferential direction.
In the illustrated example, the protrusions 34 are formed on a pair of facing surfaces 25a of the inner surface of the main body flow path 25 that face each other in the radial direction. As a result, the direction in which the first communication portion 26 opens into the main liquid chamber 14 coincides with the circumferential direction and the direction orthogonal to the facing direction. Further, the direction in which the second communication portion 27 opens into the auxiliary liquid chamber 15 also coincides with the circumferential direction and the direction orthogonal to the facing direction.

The protrusion 34 may be appropriately changed, for example, on the inner surface of the main body flow path 25, for example, a pair of facing surfaces facing each other in the axial direction. In this configuration, the direction in which the first communication portion 26 and the second communication portion 27 open into the main liquid chamber 14 or the sub liquid chamber 15 may be the radial direction.
Further, only the first communication portion 26 of the first communication portion 26 and the second communication portion 27 may be opened in the main liquid chamber 14 in the circumferential direction and the direction orthogonal to the facing direction, or the first communication portion 26 may be opened. Both the communication portion 26 and the second communication portion 27 may be opened in the main liquid chamber 14 or the sub liquid chamber 15 in a direction different from the circumferential direction and the direction orthogonal to the facing direction.

The plurality of protrusions 34 have the same shape and the same size as each other. In the illustrated example, the plurality of protrusions 34 have the same shape and the same size. The protrusion 34 has a triangular shape in which two of the three corners are located on the facing surface 25a of the main body flow path 25 when viewed from the axial direction. In the illustrated example, the protrusion 34 has an isosceles triangle shape having an obtuse angle when viewed from the axial direction. The protrusion 34 is arranged on the inner surface of the main body flow path 25 over half a circumference or more in the main body flow path 25. The plurality of protrusions 34 are arranged so as to be connected in the circumferential direction.

A protrusion 34 provided on one facing surface 25a and a portion of the other facing surface 25a located between the protrusions 34 adjacent to each other in the circumferential direction face each other in the facing direction. There is. In the illustrated example, the top of the protrusion 34 provided on one facing surface 25a is located between the protruding portions 34 adjacent to each other in the circumferential direction on the other facing surface 25a in the facing direction. Are facing each other. In the above configuration, the plan-view shape of a portion of the main body flow path 25 in which a plurality of protrusions 34 are arranged along the circumferential direction (hereinafter referred to as a protrusion region) is bent in the radial direction and in the circumferential direction. It has an extending wave shape. In the illustrated example, the plan-view shape of the protrusion region of the main body flow path 25 is a wave shape that bends in the radial direction and extends in the circumferential direction with the same amplitude and the same period over the entire circumference. ..
The distance X between the pair of facing surfaces 25a is larger than twice the height Y of the protrusion 34 protruding from the facing surfaces 25a. The distance X is between virtual surfaces in which the non-arranged portion of the protrusion 34 or the connection portion with the protrusion 34 on each of the pair of facing surfaces 25a extends in the circumferential direction (flow path direction). , The distance in the radial direction in the protrusion region. The protrusion height Y is a radial distance from the virtual surface to the top of the protrusion 34.

At least one of the first communication portion 26 and the second communication portion 27 is open to a portion of the main body flow path 25 that is separated from the protrusion region in the circumferential direction. In the illustrated example, the first communication portion 26 is opened from a portion of the main body flow path 25 that is continuous with the other side in the circumferential direction with respect to the protrusion region to a region extending over the other end edge in the circumferential direction. There is. The second communication portion 27 opens from a portion of the main body flow path 25 that is continuous with one side in the circumferential direction with respect to the protrusion region to a region extending over the edge on one side in the circumferential direction. The circumferential length of each of the first communication portion 26 and the second communication portion 27 is shorter than the circumferential length of the main body flow path 25 in the protrusion region. The circumferential length of the first communication portion 26 is longer than the circumferential length of the second communication portion 27.

Of the inner surface of the main body flow path 25, the end portion on the other side in the circumferential direction on the bottom surface facing the main liquid chamber 14 side along the axial direction gradually flows in the axial direction from one side in the circumferential direction toward the other side. An inclined surface 25b that narrows the road width is formed. The circumferential length of the inclined surface 25b is the circumferential length of the region of the main body flow path 25 that extends from the portion of the main body flow path 25 that is continuous with the other side in the circumferential direction to the other end edge in the circumferential direction. It is about half of that. The inclined surface 25b reaches the other end edge of the main body flow path 25 in the circumferential direction. Of the main body flow path 25, the axial flow path width at the other end edge in the circumferential direction is about half of the axial flow path width in the other portion.

In the vibration isolator 10 having such a configuration, both mounting members 11 and 12 are relatively displaced while elastically deforming the elastic body 13 at the time of vibration input. Then, the liquid pressure in the main liquid chamber 14 fluctuates, the liquid L in the main liquid chamber 14 flows into the sub liquid chamber 15 through the limiting passage 24, and the liquid L in the sub liquid chamber 15 flows into the limiting passage 24. It flows into the main liquid chamber 14 through the main liquid chamber 14.

Then, according to the vibration isolator 10 according to the present embodiment, when a large load (vibration) is input, the liquid L collides with the protrusions 34 provided on the pair of facing surfaces 25a and causes the main body flow path 25. Since the liquid L circulates, the energy loss due to the collision of the liquid L with the protrusion 34 and the energy loss due to the friction between the liquid L and the protrusion 34 occur, so that the pressure loss of the liquid L flowing through the limiting passage 24 occurs. Can be increased, and the flow velocity of the liquid L passing through the first communication portion 26 and the second communication portion 27 can be reduced. As a result, the liquid L that has passed through one of the first communication portion 26 and the second communication portion 27 and has flowed into the main liquid chamber 14 or the sub liquid chamber 15 and the liquid L in the main liquid chamber 14 or the sub liquid chamber 15 The difference in flow velocity between the liquid L and the liquid L can be suppressed to a small value, and the generation of vortices due to the difference in flow velocity and the generation of bubbles due to this vortex can be suppressed.

Further, since the distance X between the pair of facing surfaces 25a in the main body flow path 25 is larger than twice the protrusion height Y from the facing surfaces 25a of the protrusion 34, the protrusion in the main body flow path 25 A region extending in the circumferential direction is secured without interfering with the portion 34. Therefore, when a normal load is input to the anti-vibration device 10, it is possible to make it difficult for the above-mentioned pressure loss to occur, and it is possible to stably exhibit the desired anti-vibration characteristics.

Further, since the first communication portion 26 and the second communication portion 27 are open to the main liquid chamber 14 or the sub liquid chamber 15 in the circumferential direction and the axial direction orthogonal to the opposite direction, the inside of the main body flow path 25 is formed. The liquid L flowing along the protrusion 34 is bent at a right angle in the direction of its flow and flows into the main liquid chamber 14 or the auxiliary liquid chamber 15 from one of the first communication portion 26 and the second communication portion 27. Will be done. Therefore, even if a large load is input to the vibration isolator 10, the flow velocity of the liquid L flowing into the main liquid chamber 14 or the sub liquid chamber 15 can be surely reduced.

Further, when the liquid L flows into the main liquid chamber 14 through the plurality of pores 31, the liquid L flows through the pores 31 while being pressure-lossed by the first barrier 28 in which the pores 31 are formed. , The flow velocity of the liquid L flowing into the main liquid chamber 14 can be suppressed. Moreover, since the liquid L flows through a plurality of pores 31 instead of a single pore 31, the liquid L can be branched into a plurality of pores 31 and circulated, and the liquid L that has passed through the individual pores 31 can be circulated. The flow velocity can be reduced. Further, even if bubbles are generated in the restricted passage 24, since a plurality of pores 31 are arranged, the generated bubbles can be separated from each other in the main liquid chamber 14, and the bubbles merge. It is possible to suppress the growth and make it easier to maintain the state in which the bubbles are finely dispersed.

Further, since the first communication portion 26 and the second communication portion 27 are open in the portion of the main body flow path 25 that is separated from the protrusion region in the circumferential direction, a large load is input to the vibration isolator 10. At that time, after the flow velocity of the liquid L is reduced by the plurality of protrusions 34 as described above, the liquid L can flow into the main liquid chamber 14 or the sub liquid chamber 15. Therefore, even if a large load is input to the vibration isolator 10, the flow velocity of the liquid L flowing into the main liquid chamber 14 or the sub liquid chamber 15 can be reduced more reliably.

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

For example, the shape of the protrusion 34 when viewed from the axial direction is not limited to a triangular shape, but may be appropriately changed such as a semicircular shape or a square shape. Further, the circumferential length of each of the first communication portion 26 and the second communication portion 27 may be equal to or greater than the circumferential length of the main body flow path 25 in the protrusion region. Further, the length of the first communication portion 26 in the circumferential direction may be set to be equal to or less than the length of the second communication portion 27 in the circumferential direction. Further, the protrusion 34 may be arranged on the inner surface of the main body flow path 25 over less than half the circumference of the main body flow path 25, or may be arranged over the entire circumference of the main body flow path 25. The plurality of protrusions 34 may be arranged at intervals in the circumferential direction.
Further, at least a part of each of the first communication portion 26 and the second communication portion 27 may be opened in the protrusion region of the main body flow path 25.
Further, the inclined surface 25b may be formed at one end of the inner surface of the main body flow path 25 along the circumferential direction on the top surface facing the auxiliary liquid chamber 15 side along the axial direction. Further, the inclined surface 25b does not have to be arranged on the inner surface of the main body flow path 25.

Further, in the above embodiment, the pores 31 are formed in the first barrier 28, but they may be formed in the second barrier 29, or may be formed in both the first barrier 28 and the second barrier 29. ..
Further, in the above-described embodiment, the pores 31 are formed in a truncated cone shape with a gradually reduced diameter, but may be formed in a columnar shape (straight circular hole shape) or the like.
Further, in the above-described embodiment, the plurality of pores 31 are formed in a circular shape in a cross-sectional view, but the present invention is not limited to this. For example, the plurality of pores 31 may be appropriately changed, such as forming a cross-sectional viewing angle shape.
Further, in the above-described embodiment, the first communication portion 26 includes a plurality of pores 31, but for example, a configuration having no pores 31 or an opening having a diameter larger than the pores 31 and both of the pores 31. A configuration or the like having the above may be adopted. Further, the second communication portion 27 may include a plurality of openings 32 arranged along the circumferential direction (flow path direction of the main body flow path 25).

Further, in the above embodiment, the partition member 16 is arranged at the lower end portion of the first mounting member 11, and the outer peripheral portion 22 of the partition member 16 is brought into contact with the lower end opening edge of the first mounting member 11, for example. The first mounting member is formed by arranging the member 16 sufficiently above the lower end opening edge of the first mounting member 11 and arranging the diaphragm 20 on the lower side of the partition member 16, that is, on the lower end of the first mounting member 11. The auxiliary liquid chamber 15 may be formed from the lower end of 11 to the bottom surface of the diaphragm 20.

Further, in the above-described embodiment, the compression type vibration isolator 10 in which a positive pressure acts on the main liquid chamber 14 when a supporting load acts has been described, but the main liquid chamber 14 is located on the lower side in the vertical direction and The auxiliary liquid chamber 15 is attached so as to be located on the upper side in the vertical direction, and can be applied to a suspension-type anti-vibration device in which a negative pressure acts on the main liquid chamber 14 when a supporting load acts.
Further, in the above-described embodiment, the partition member 16 partitions the liquid chamber 19 in the first mounting member 11 into a main liquid chamber 14 having an elastic body 13 as a part of a wall surface and a sub liquid chamber 15. , Not limited to this. For example, instead of providing the diaphragm 20, the elastic body 13 may be provided, and instead of providing the auxiliary liquid chamber 15, a pressure receiving liquid chamber having the elastic body 13 as a part of the wall surface may be provided. For example, the partition member 16 partitions the liquid chamber 19 in the first mounting member 11 in which the liquid L is sealed into the first liquid chamber 14 and the second liquid chamber 15, and the first liquid chamber 14 and the second liquid chamber 15 At least one of them can be appropriately modified to another configuration having the elastic body 13 as a part of the wall surface.
Further, the vibration isolator 10 according to the present invention is not limited to the engine mount of the vehicle, and can be applied to other than the engine mount. For example, it can be applied to a mount of a generator mounted on a construction machine, or it can be applied to a mount of a machine installed in a factory or the like.

In addition, it is possible to replace the constituent elements in the above-described embodiment with well-known constituent elements as appropriate without departing from the spirit of the present invention, and the above-mentioned modified examples may be appropriately combined.

10 Anti-vibration device 11 1st mounting member 12 2nd mounting member 13 Elastic body 14 Main liquid chamber (1st liquid chamber)
15 Secondary liquid chamber (second liquid chamber)
16 Partition member 19 Liquid chamber 24 Restricted passage 25 Main body flow path 25a Facing surface 26 1st communication part 27 2nd communication part 28 1st barrier 29 2nd barrier 31 Pore 34 Protrusion L Liquid X Interval Y Protrusion height

Claims (7)

A tubular first mounting member connected to either one of the vibration generating portion and the vibration receiving portion, and a second mounting member connected to the other.
An elastic body that elastically connects these two mounting members,
A partition member for partitioning the liquid chamber in the first mounting member in which the liquid is sealed into the first liquid chamber and the second liquid chamber is provided, and the liquid chamber is provided.
A liquid-filled type anti-vibration device in which a limiting passage for communicating the first liquid chamber and the second liquid chamber is formed in the partition member.
The restricted passage includes a first communication portion that opens into the first liquid chamber, a second communication portion that opens into the second liquid chamber, and a main body flow path that communicates the first communication portion with the second communication portion. With
Of the inner surface of the body passage, the pair of opposing surfaces facing each other, are projections projecting in opposite directions opposite to each other, chosen more, the flow path along the flow direction of the body passage is provided,
The protrusion has a triangular shape in which two of the three corners are located on the facing surfaces.
The protrusion provided on one of the facing surfaces and the portion of the other facing surface located between the protrusions adjacent to each other in the flow path direction face each other in the facing direction. And
An anti-vibration device characterized in that the distance between the pair of facing surfaces is larger than twice the height of protrusion of the protrusion from the facing surfaces. At least one of the first communication portion and the second communication portion is open to the first liquid chamber or the second liquid chamber in a direction orthogonal to the flow path direction and the opposite direction. The anti-vibration device according to claim 1. 1 or claim 1, wherein at least one of the first communication portion and the second communication portion includes a plurality of pores penetrating the first liquid chamber or the barrier facing the second liquid chamber. 2. The anti-vibration device according to 2. At least one of the first communication portion and the second communication portion is separated from the portion of the main body flow path in which a plurality of protrusions are arranged along the flow path direction in the flow path direction. The anti-vibration device according to any one of claims 1 to 3, wherein the vibration isolator is open to a portion. The anti-vibration device according to any one of claims 1 to 4, wherein the triangular apex angle exhibited by the protrusion is an obtuse angle. The anti-vibration device according to any one of claims 1 to 5, wherein the plurality of protrusions have the same shape as each other. The anti-vibration device according to claim 6, wherein the plurality of protrusions have the same size as each other.

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